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java.lang.Object
- java.util.Scanner

All Implemented Interfaces:: Closeable,AutoCloseable,Iterator<String>

public final classScannerextendsObjectimplementsIterator<String>,Closeable

A simple text scanner which can parse primitive types and strings using regular expressions.

AScanner breaks its input into tokens using a delimiter pattern, which by default matches whitespace. The resulting tokens may then be converted into values of different types using the variousnext methods.

For example, this code allows a user to read a number fromSystem.in:

     Scanner sc = new Scanner(System.in);     int i = sc.nextInt();

As another example, this code allowslong types to be assigned from entries in a filemyNumbers:

      Scanner sc = new Scanner(new File("myNumbers"));      while (sc.hasNextLong()) {          long aLong = sc.nextLong();      }

The scanner can also use delimiters other than whitespace. This example reads several items in from a string:

     String input = "1 fish 2 fish red fish blue fish";     Scanner s = new Scanner(input).useDelimiter("\\s*fish\\s*");     System.out.println(s.nextInt());     System.out.println(s.nextInt());     System.out.println(s.next());     System.out.println(s.next());     s.close();

prints the following output:

     1     2     red     blue

The same output can be generated with this code, which uses a regular expression to parse all four tokens at once:

     String input = "1 fish 2 fish red fish blue fish";     Scanner s = new Scanner(input);     s.findInLine("(\\d+) fish (\\d+) fish (\\w+) fish (\\w+)");     MatchResult result = s.match();     for (int i=1; i<=result.groupCount(); i++)         System.out.println(result.group(i));     s.close();

Thedefault whitespace delimiter used by a scanner is as recognized byCharacter.isWhitespace. Thereset() method will reset the value of the scanner's delimiter to the default whitespace delimiter regardless of whether it was previously changed.

A scanning operation may block waiting for input.

Thenext() andhasNext() methods and their primitive-type companion methods (such asnextInt() andhasNextInt()) first skip any input that matches the delimiter pattern, and then attempt to return the next token. BothhasNext andnext methods may block waiting for further input. Whether ahasNext method blocks has no connection to whether or not its associatednext method will block.

ThefindInLine(java.lang.String),findWithinHorizon(java.lang.String, int), andskip(java.util.regex.Pattern) methods operate independently of the delimiter pattern. These methods will attempt to match the specified pattern with no regard to delimiters in the input and thus can be used in special circumstances where delimiters are not relevant. These methods may block waiting for more input.

When a scanner throws anInputMismatchException, the scanner will not pass the token that caused the exception, so that it may be retrieved or skipped via some other method.

Depending upon the type of delimiting pattern, empty tokens may be returned. For example, the pattern"\\s+" will return no empty tokens since it matches multiple instances of the delimiter. The delimiting pattern"\\s" could return empty tokens since it only passes one space at a time.

A scanner can read text from any object which implements theReadable interface. If an invocation of the underlying readable'sReadable.read(java.nio.CharBuffer) method throws anIOException then the scanner assumes that the end of the input has been reached. The most recentIOException thrown by the underlying readable can be retrieved via theioException() method.

When aScanner is closed, it will close its input source if the source implements theCloseable interface.

AScanner is not safe for multithreaded use without external synchronization.

Unless otherwise mentioned, passing anull parameter into any method of aScanner will cause aNullPointerException to be thrown.

A scanner will default to interpreting numbers as decimal unless a different radix has been set by using theuseRadix(int) method. Thereset() method will reset the value of the scanner's radix to10 regardless of whether it was previously changed.

Localized numbers

An instance of this class is capable of scanning numbers in the standard formats as well as in the formats of the scanner's locale. A scanner's initial localeis the value returned by theLocale.getDefault() method; it may be changed via theuseLocale(java.util.Locale) method. Thereset() method will reset the value of the scanner's locale to the initial locale regardless of whether it was previously changed.

The localized formats are defined in terms of the following parameters, which for a particular locale are taken from that locale'sDecimalFormat object,df, and its andDecimalFormatSymbols object,dfs.

LocalGroupSeparator   The character used to separate thousands groups,i.e., dfs.getGroupingSeparator()
LocalDecimalSeparator   The character used for the decimal point,i.e., dfs.getDecimalSeparator()
LocalPositivePrefix   The string that appears before a positive number (may be empty),i.e., df.getPositivePrefix()
LocalPositiveSuffix   The string that appears after a positive number (may be empty),i.e., df.getPositiveSuffix()
LocalNegativePrefix   The string that appears before a negative number (may be empty),i.e., df.getNegativePrefix()
LocalNegativeSuffix   The string that appears after a negative number (may be empty),i.e., df.getNegativeSuffix()
LocalNaN   The string that represents not-a-number for floating-point values,i.e., dfs.getNaN()
LocalInfinity   The string that represents infinity for floating-point values,i.e., dfs.getInfinity()

Number syntax

The strings that can be parsed as numbers by an instance of this class are specified in terms of the following regular-expression grammar, where Rmax is the highest digit in the radix being used (for example, Rmax is 9 in base 10).

NonASCIIDigit :: = A non-ASCII character c for whichCharacter.isDigit(c) returns true

Non0Digit :: = [1-Rmax] |NonASCIIDigit

Digit :: = [0-Rmax] |NonASCIIDigit

GroupedNumeral ::

`= (`	Non0DigitDigit`?`Digit`?`
	`(` LocalGroupSeparatorDigitDigitDigit `)+ )`

Numeral :: = ( (Digit+ ) |GroupedNumeral )

Integer :: = ( [-+]? (Numeral ) )

|LocalPositivePrefixNumeralLocalPositiveSuffix

|LocalNegativePrefixNumeralLocalNegativeSuffix

DecimalNumeral :: =Numeral

|NumeralLocalDecimalSeparatorDigit*

|LocalDecimalSeparatorDigit+

Exponent :: = ( [eE] [+-]?Digit+ )

Decimal :: = ( [-+]?DecimalNumeralExponent? )

|LocalPositivePrefixDecimalNumeralLocalPositiveSuffixExponent?

|LocalNegativePrefixDecimalNumeralLocalNegativeSuffixExponent?

HexFloat :: = [-+]? 0[xX][0-9a-fA-F]*\.[0-9a-fA-F]+ ([pP][-+]?[0-9]+)?

NonNumber :: = NaN |LocalNan | Infinity |LocalInfinity

SignedNonNumber :: = ( [-+]?NonNumber )

|LocalPositivePrefixNonNumberLocalPositiveSuffix

|LocalNegativePrefixNonNumberLocalNegativeSuffix

Float :: =Decimal

|HexFloat

|SignedNonNumber

Whitespace is not significant in the above regular expressions.

Since:: 1.5

Constructor Summary

Constructors
Constructor and Description
`Scanner(File source)` Constructs a new`Scanner` that produces values scanned from the specified file.
`Scanner(File source,String charsetName)` Constructs a new`Scanner` that produces values scanned from the specified file.
`Scanner(InputStream source)` Constructs a new`Scanner` that produces values scanned from the specified input stream.
`Scanner(InputStream source,String charsetName)` Constructs a new`Scanner` that produces values scanned from the specified input stream.
`Scanner(Path source)` Constructs a new`Scanner` that produces values scanned from the specified file.
`Scanner(Path source,String charsetName)` Constructs a new`Scanner` that produces values scanned from the specified file.
`Scanner(Readable source)` Constructs a new`Scanner` that produces values scanned from the specified source.
`Scanner(ReadableByteChannel source)` Constructs a new`Scanner` that produces values scanned from the specified channel.
`Scanner(ReadableByteChannel source,String charsetName)` Constructs a new`Scanner` that produces values scanned from the specified channel.
`Scanner(String source)` Constructs a new`Scanner` that produces values scanned from the specified string.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`close()` Closes this scanner.
`Pattern`	`delimiter()` Returns the`Pattern` this`Scanner` is currently using to match delimiters.
`String`	`findInLine(Pattern pattern)` Attempts to find the next occurrence of the specified pattern ignoring delimiters.
`String`	`findInLine(String pattern)` Attempts to find the next occurrence of a pattern constructed from the specified string, ignoring delimiters.
`String`	`findWithinHorizon(Pattern pattern, int horizon)` Attempts to find the next occurrence of the specified pattern.
`String`	`findWithinHorizon(String pattern, int horizon)` Attempts to find the next occurrence of a pattern constructed from the specified string, ignoring delimiters.
`boolean`	`hasNext()` Returns true if this scanner has another token in its input.
`boolean`	`hasNext(Pattern pattern)` Returns true if the next complete token matches the specified pattern.
`boolean`	`hasNext(String pattern)` Returns true if the next token matches the pattern constructed from the specified string.
`boolean`	`hasNextBigDecimal()` Returns true if the next token in this scanner's input can be interpreted as a`BigDecimal` using the`nextBigDecimal()` method.
`boolean`	`hasNextBigInteger()` Returns true if the next token in this scanner's input can be interpreted as a`BigInteger` in the default radix using the`nextBigInteger()` method.
`boolean`	`hasNextBigInteger(int radix)` Returns true if the next token in this scanner's input can be interpreted as a`BigInteger` in the specified radix using the`nextBigInteger()` method.
`boolean`	`hasNextBoolean()` Returns true if the next token in this scanner's input can be interpreted as a boolean value using a case insensitive pattern created from the string "true\|false".
`boolean`	`hasNextByte()` Returns true if the next token in this scanner's input can be interpreted as a byte value in the default radix using the`nextByte()` method.
`boolean`	`hasNextByte(int radix)` Returns true if the next token in this scanner's input can be interpreted as a byte value in the specified radix using the`nextByte()` method.
`boolean`	`hasNextDouble()` Returns true if the next token in this scanner's input can be interpreted as a double value using the`nextDouble()` method.
`boolean`	`hasNextFloat()` Returns true if the next token in this scanner's input can be interpreted as a float value using the`nextFloat()` method.
`boolean`	`hasNextInt()` Returns true if the next token in this scanner's input can be interpreted as an int value in the default radix using the`nextInt()` method.
`boolean`	`hasNextInt(int radix)` Returns true if the next token in this scanner's input can be interpreted as an int value in the specified radix using the`nextInt()` method.
`boolean`	`hasNextLine()` Returns true if there is another line in the input of this scanner.
`boolean`	`hasNextLong()` Returns true if the next token in this scanner's input can be interpreted as a long value in the default radix using the`nextLong()` method.
`boolean`	`hasNextLong(int radix)` Returns true if the next token in this scanner's input can be interpreted as a long value in the specified radix using the`nextLong()` method.
`boolean`	`hasNextShort()` Returns true if the next token in this scanner's input can be interpreted as a short value in the default radix using the`nextShort()` method.
`boolean`	`hasNextShort(int radix)` Returns true if the next token in this scanner's input can be interpreted as a short value in the specified radix using the`nextShort()` method.
`IOException`	`ioException()` Returns the`IOException` last thrown by this`Scanner`'s underlying`Readable`.
`Locale`	`locale()` Returns this scanner's locale.
`MatchResult`	`match()` Returns the match result of the last scanning operation performed by this scanner.
`String`	`next()` Finds and returns the next complete token from this scanner.
`String`	`next(Pattern pattern)` Returns the next token if it matches the specified pattern.
`String`	`next(String pattern)` Returns the next token if it matches the pattern constructed from the specified string.
`BigDecimal`	`nextBigDecimal()` Scans the next token of the input as a`BigDecimal`.
`BigInteger`	`nextBigInteger()` Scans the next token of the input as a`BigInteger`.
`BigInteger`	`nextBigInteger(int radix)` Scans the next token of the input as a`BigInteger`.
`boolean`	`nextBoolean()` Scans the next token of the input into a boolean value and returns that value.
`byte`	`nextByte()` Scans the next token of the input as a`byte`.
`byte`	`nextByte(int radix)` Scans the next token of the input as a`byte`.
`double`	`nextDouble()` Scans the next token of the input as a`double`.
`float`	`nextFloat()` Scans the next token of the input as a`float`.
`int`	`nextInt()` Scans the next token of the input as an`int`.
`int`	`nextInt(int radix)` Scans the next token of the input as an`int`.
`String`	`nextLine()` Advances this scanner past the current line and returns the input that was skipped.
`long`	`nextLong()` Scans the next token of the input as a`long`.
`long`	`nextLong(int radix)` Scans the next token of the input as a`long`.
`short`	`nextShort()` Scans the next token of the input as a`short`.
`short`	`nextShort(int radix)` Scans the next token of the input as a`short`.
`int`	`radix()` Returns this scanner's default radix.
`void`	`remove()` The remove operation is not supported by this implementation of`Iterator`.
`Scanner`	`reset()` Resets this scanner.
`Scanner`	`skip(Pattern pattern)` Skips input that matches the specified pattern, ignoring delimiters.
`Scanner`	`skip(String pattern)` Skips input that matches a pattern constructed from the specified string.
`String`	`toString()` Returns the string representation of this`Scanner`.
`Scanner`	`useDelimiter(Pattern pattern)` Sets this scanner's delimiting pattern to the specified pattern.
`Scanner`	`useDelimiter(String pattern)` Sets this scanner's delimiting pattern to a pattern constructed from the specified`String`.
`Scanner`	`useLocale(Locale locale)` Sets this scanner's locale to the specified locale.
`Scanner`	`useRadix(int radix)` Sets this scanner's default radix to the specified radix.

Methods inherited from class java.lang.Object
clone,equals,finalize,getClass,hashCode,notify,notifyAll,wait,wait,wait

- Constructor Detail
  - Scanner
```
public Scanner(Readable source)
```
    Constructs a newScanner that produces values scanned from the specified source.
    Parameters:
    source - A character source implementing theReadable interface
  - Scanner
```
public Scanner(InputStream source)
```
    Constructs a newScanner that produces values scanned from the specified input stream. Bytes from the stream are converted into characters using the underlying platform'sdefault charset.
    Parameters:
    source - An input stream to be scanned
  - Scanner
```
public Scanner(InputStream source,String charsetName)
```
    Constructs a newScanner that produces values scanned from the specified input stream. Bytes from the stream are converted into characters using the specified charset.
    Parameters:
    source - An input stream to be scanned
    charsetName - The encoding type used to convert bytes from the stream into characters to be scanned
    Throws:
    IllegalArgumentException - if the specified character set does not exist
  - Scanner
```
public Scanner(File source)        throwsFileNotFoundException
```
    Constructs a newScanner that produces values scanned from the specified file. Bytes from the file are converted into characters using the underlying platform'sdefault charset.
    Parameters:
    source - A file to be scanned
    Throws:
    FileNotFoundException - if source is not found
  - Scanner
```
public Scanner(File source,String charsetName)        throwsFileNotFoundException
```
    Constructs a newScanner that produces values scanned from the specified file. Bytes from the file are converted into characters using the specified charset.
    Parameters:
    source - A file to be scanned
    charsetName - The encoding type used to convert bytes from the file into characters to be scanned
    Throws:
    FileNotFoundException - if source is not found
    IllegalArgumentException - if the specified encoding is not found
  - Scanner
```
public Scanner(Path source)        throwsIOException
```
    Constructs a newScanner that produces values scanned from the specified file. Bytes from the file are converted into characters using the underlying platform'sdefault charset.
    Parameters:
    source - the path to the file to be scanned
    Throws:
    IOException - if an I/O error occurs opening source
    Since:
    1.7
  - Scanner
```
public Scanner(Path source,String charsetName)        throwsIOException
```
    Constructs a newScanner that produces values scanned from the specified file. Bytes from the file are converted into characters using the specified charset.
    Parameters:
    source - the path to the file to be scanned
    charsetName - The encoding type used to convert bytes from the file into characters to be scanned
    Throws:
    IOException - if an I/O error occurs opening source
    IllegalArgumentException - if the specified encoding is not found
    Since:
    1.7
  - Scanner
```
public Scanner(String source)
```
    Constructs a newScanner that produces values scanned from the specified string.
    Parameters:
    source - A string to scan
  - Scanner
```
public Scanner(ReadableByteChannel source)
```
    Constructs a newScanner that produces values scanned from the specified channel. Bytes from the source are converted into characters using the underlying platform'sdefault charset.
    Parameters:
    source - A channel to scan
  - Scanner
```
public Scanner(ReadableByteChannel source,String charsetName)
```
    Constructs a newScanner that produces values scanned from the specified channel. Bytes from the source are converted into characters using the specified charset.
    Parameters:
    source - A channel to scan
    charsetName - The encoding type used to convert bytes from the channel into characters to be scanned
    Throws:
    IllegalArgumentException - if the specified character set does not exist
- Method Detail
  - close
```
public void close()
```
    Closes this scanner.
    If this scanner has not yet been closed then if its underlyingreadable also implements theCloseable interface then the readable'sclose method will be invoked. If this scanner is already closed then invoking this method will have no effect.
    Attempting to perform search operations after a scanner has been closed will result in anIllegalStateException.
    Specified by:
    close in interface Closeable
    Specified by:
    close in interface AutoCloseable
  - ioException
```
public IOException ioException()
```
    Returns theIOException last thrown by thisScanner's underlyingReadable. This method returnsnull if no such exception exists.
    Returns:
    the last exception thrown by this scanner's readable
  - delimiter
```
public Pattern delimiter()
```
    Returns thePattern thisScanner is currently using to match delimiters.
    Returns:
    this scanner's delimiting pattern.
  - useDelimiter
```
public Scanner useDelimiter(Pattern pattern)
```
    Sets this scanner's delimiting pattern to the specified pattern.
    Parameters:
    pattern - A delimiting pattern
    Returns:
    this scanner
  - useDelimiter
```
public Scanner useDelimiter(String pattern)
```
    Sets this scanner's delimiting pattern to a pattern constructed from the specifiedString.
    An invocation of this method of the formuseDelimiter(pattern) behaves in exactly the same way as the invocationuseDelimiter(Pattern.compile(pattern)).
    Invoking thereset() method will set the scanner's delimiter to thedefault.
    Parameters:
    pattern - A string specifying a delimiting pattern
    Returns:
    this scanner
  - locale
```
public Locale locale()
```
    Returns this scanner's locale.
    A scanner's locale affects many elements of its default primitive matching regular expressions; seelocalized numbers above.
    Returns:
    this scanner's locale
  - useLocale
```
public Scanner useLocale(Locale locale)
```
    Sets this scanner's locale to the specified locale.
    A scanner's locale affects many elements of its default primitive matching regular expressions; seelocalized numbers above.
    Invoking thereset() method will set the scanner's locale to theinitial locale.
    Parameters:
    locale - A string specifying the locale to use
    Returns:
    this scanner
  - radix
```
public int radix()
```
    Returns this scanner's default radix.
    A scanner's radix affects elements of its default number matching regular expressions; seelocalized numbers above.
    Returns:
    the default radix of this scanner
  - useRadix
```
public Scanner useRadix(int radix)
```
    Sets this scanner's default radix to the specified radix.
    A scanner's radix affects elements of its default number matching regular expressions; seelocalized numbers above.
    If the radix is less thanCharacter.MIN_RADIX or greater thanCharacter.MAX_RADIX, then anIllegalArgumentException is thrown.
    Invoking thereset() method will set the scanner's radix to10.
    Parameters:
    radix - The radix to use when scanning numbers
    Returns:
    this scanner
    Throws:
    IllegalArgumentException - if radix is out of range
  - match
```
public MatchResult match()
```
    Returns the match result of the last scanning operation performed by this scanner. This method throwsIllegalStateException if no match has been performed, or if the last match was not successful.
    The variousnextmethods ofScanner make a match result available if they complete without throwing an exception. For instance, after an invocation of thenextInt() method that returned an int, this method returns aMatchResult for the search of theInteger regular expression defined above. Similarly thefindInLine(java.lang.String),findWithinHorizon(java.lang.String, int), andskip(java.util.regex.Pattern) methods will make a match available if they succeed.
    Returns:
    a match result for the last match operation
    Throws:
    IllegalStateException - If no match result is available
  - toString
```
public String toString()
```
    Returns the string representation of thisScanner. The string representation of aScanner contains information that may be useful for debugging. The exact format is unspecified.
    Overrides:
    toString in class Object
    Returns:
    The string representation of this scanner
  - hasNext
```
public boolean hasNext()
```
    Returns true if this scanner has another token in its input. This method may block while waiting for input to scan. The scanner does not advance past any input.
    Specified by:
    hasNext in interface Iterator<String>
    Returns:
    true if and only if this scanner has another token
    Throws:
    IllegalStateException - if this scanner is closed
    See Also:
    Iterator
  - next
```
public String next()
```
    Finds and returns the next complete token from this scanner. A complete token is preceded and followed by input that matches the delimiter pattern. This method may block while waiting for input to scan, even if a previous invocation ofhasNext() returnedtrue.
    Specified by:
    next in interface Iterator<String>
    Returns:
    the next token
    Throws:
    NoSuchElementException - if no more tokens are available
    IllegalStateException - if this scanner is closed
    See Also:
    Iterator
  - remove
```
public void remove()
```
    The remove operation is not supported by this implementation ofIterator.
    Specified by:
    remove in interface Iterator<String>
    Throws:
    UnsupportedOperationException - if this method is invoked.
    See Also:
    Iterator
  - hasNext
```
public boolean hasNext(String pattern)
```
    Returns true if the next token matches the pattern constructed from the specified string. The scanner does not advance past any input.
    An invocation of this method of the formhasNext(pattern) behaves in exactly the same way as the invocationhasNext(Pattern.compile(pattern)).
    Parameters:
    pattern - a string specifying the pattern to scan
    Returns:
    true if and only if this scanner has another token matching the specified pattern
    Throws:
    IllegalStateException - if this scanner is closed
  - next
```
public String next(String pattern)
```
    Returns the next token if it matches the pattern constructed from the specified string. If the match is successful, the scanner advances past the input that matched the pattern.
    An invocation of this method of the formnext(pattern) behaves in exactly the same way as the invocationnext(Pattern.compile(pattern)).
    Parameters:
    pattern - a string specifying the pattern to scan
    Returns:
    the next token
    Throws:
    NoSuchElementException - if no such tokens are available
    IllegalStateException - if this scanner is closed
  - hasNext
```
public boolean hasNext(Pattern pattern)
```
    Returns true if the next complete token matches the specified pattern. A complete token is prefixed and postfixed by input that matches the delimiter pattern. This method may block while waiting for input. The scanner does not advance past any input.
    Parameters:
    pattern - the pattern to scan for
    Returns:
    true if and only if this scanner has another token matching the specified pattern
    Throws:
    IllegalStateException - if this scanner is closed
  - next
```
public String next(Pattern pattern)
```
    Returns the next token if it matches the specified pattern. This method may block while waiting for input to scan, even if a previous invocation ofhasNext(Pattern) returnedtrue. If the match is successful, the scanner advances past the input that matched the pattern.
    Parameters:
    pattern - the pattern to scan for
    Returns:
    the next token
    Throws:
    NoSuchElementException - if no more tokens are available
    IllegalStateException - if this scanner is closed
  - hasNextLine
```
public boolean hasNextLine()
```
    Returns true if there is another line in the input of this scanner. This method may block while waiting for input. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner has another line of input
    Throws:
    IllegalStateException - if this scanner is closed
  - nextLine
```
public String nextLine()
```
    Advances this scanner past the current line and returns the input that was skipped. This method returns the rest of the current line, excluding any line separator at the end. The position is set to the beginning of the next line.
    Since this method continues to search through the input looking for a line separator, it may buffer all of the input searching for the line to skip if no line separators are present.
    Returns:
    the line that was skipped
    Throws:
    NoSuchElementException - if no line was found
    IllegalStateException - if this scanner is closed
  - findInLine
```
public String findInLine(String pattern)
```
    Attempts to find the next occurrence of a pattern constructed from the specified string, ignoring delimiters.
    An invocation of this method of the formfindInLine(pattern) behaves in exactly the same way as the invocationfindInLine(Pattern.compile(pattern)).
    Parameters:
    pattern - a string specifying the pattern to search for
    Returns:
    the text that matched the specified pattern
    Throws:
    IllegalStateException - if this scanner is closed
  - findInLine
```
public String findInLine(Pattern pattern)
```
    Attempts to find the next occurrence of the specified pattern ignoring delimiters. If the pattern is found before the next line separator, the scanner advances past the input that matched and returns the string that matched the pattern. If no such pattern is detected in the input up to the next line separator, thennull is returned and the scanner's position is unchanged. This method may block waiting for input that matches the pattern.
    Since this method continues to search through the input looking for the specified pattern, it may buffer all of the input searching for the desired token if no line separators are present.
    Parameters:
    pattern - the pattern to scan for
    Returns:
    the text that matched the specified pattern
    Throws:
    IllegalStateException - if this scanner is closed
  - findWithinHorizon
```
public String findWithinHorizon(String pattern,                       int horizon)
```
    Attempts to find the next occurrence of a pattern constructed from the specified string, ignoring delimiters.
    An invocation of this method of the formfindWithinHorizon(pattern) behaves in exactly the same way as the invocationfindWithinHorizon(Pattern.compile(pattern, horizon)).
    Parameters:
    pattern - a string specifying the pattern to search for
    Returns:
    the text that matched the specified pattern
    Throws:
    IllegalStateException - if this scanner is closed
    IllegalArgumentException - if horizon is negative
  - findWithinHorizon
```
public String findWithinHorizon(Pattern pattern,                       int horizon)
```
    Attempts to find the next occurrence of the specified pattern.
    This method searches through the input up to the specified search horizon, ignoring delimiters. If the pattern is found the scanner advances past the input that matched and returns the string that matched the pattern. If no such pattern is detected then the null is returned and the scanner's position remains unchanged. This method may block waiting for input that matches the pattern.
    A scanner will never search more thanhorizon code points beyond its current position. Note that a match may be clipped by the horizon; that is, an arbitrary match result may have been different if the horizon had been larger. The scanner treats the horizon as a transparent, non-anchoring bound (seeMatcher.useTransparentBounds(boolean) andMatcher.useAnchoringBounds(boolean)).
    If horizon is0, then the horizon is ignored and this method continues to search through the input looking for the specified pattern without bound. In this case it may buffer all of the input searching for the pattern.
    If horizon is negative, then an IllegalArgumentException is thrown.
    Parameters:
    pattern - the pattern to scan for
    Returns:
    the text that matched the specified pattern
    Throws:
    IllegalStateException - if this scanner is closed
    IllegalArgumentException - if horizon is negative
  - skip
```
public Scanner skip(Pattern pattern)
```
    Skips input that matches the specified pattern, ignoring delimiters. This method will skip input if an anchored match of the specified pattern succeeds.
    If a match to the specified pattern is not found at the current position, then no input is skipped and aNoSuchElementException is thrown.
    Since this method seeks to match the specified pattern starting at the scanner's current position, patterns that can match a lot of input (".*", for example) may cause the scanner to buffer a large amount of input.
    Note that it is possible to skip something without risking aNoSuchElementException by using a pattern that can match nothing, e.g.,sc.skip("[ \t]*").
    Parameters:
    pattern - a string specifying the pattern to skip over
    Returns:
    this scanner
    Throws:
    NoSuchElementException - if the specified pattern is not found
    IllegalStateException - if this scanner is closed
  - skip
```
public Scanner skip(String pattern)
```
    Skips input that matches a pattern constructed from the specified string.
    An invocation of this method of the formskip(pattern) behaves in exactly the same way as the invocationskip(Pattern.compile(pattern)).
    Parameters:
    pattern - a string specifying the pattern to skip over
    Returns:
    this scanner
    Throws:
    IllegalStateException - if this scanner is closed
  - hasNextBoolean
```
public boolean hasNextBoolean()
```
    Returns true if the next token in this scanner's input can be interpreted as a boolean value using a case insensitive pattern created from the string "true|false". The scanner does not advance past the input that matched.
    Returns:
    true if and only if this scanner's next token is a valid boolean value
    Throws:
    IllegalStateException - if this scanner is closed
  - nextBoolean
```
public boolean nextBoolean()
```
    Scans the next token of the input into a boolean value and returns that value. This method will throwInputMismatchException if the next token cannot be translated into a valid boolean value. If the match is successful, the scanner advances past the input that matched.
    Returns:
    the boolean scanned from the input
    Throws:
    InputMismatchException - if the next token is not a valid boolean
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextByte
```
public boolean hasNextByte()
```
    Returns true if the next token in this scanner's input can be interpreted as a byte value in the default radix using thenextByte() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a valid byte value
    Throws:
    IllegalStateException - if this scanner is closed
  - hasNextByte
```
public boolean hasNextByte(int radix)
```
    Returns true if the next token in this scanner's input can be interpreted as a byte value in the specified radix using thenextByte() method. The scanner does not advance past any input.
    Parameters:
    radix - the radix used to interpret the token as a byte value
    Returns:
    true if and only if this scanner's next token is a valid byte value
    Throws:
    IllegalStateException - if this scanner is closed
  - nextByte
```
public byte nextByte()
```
    Scans the next token of the input as abyte.
    An invocation of this method of the formnextByte() behaves in exactly the same way as the invocationnextByte(radix), whereradix is the default radix of this scanner.
    Returns:
    thebyte scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - nextByte
```
public byte nextByte(int radix)
```
    Scans the next token of the input as abyte. This method will throwInputMismatchException if the next token cannot be translated into a valid byte value as described below. If the translation is successful, the scanner advances past the input that matched.
    If the next token matches theInteger regular expression defined above then the token is converted into abyte value as if by removing all locale specific prefixes, group separators, and locale specific suffixes, then mapping non-ASCII digits into ASCII digits viaCharacter.digit, prepending a negative sign (-) if the locale specific negative prefixes and suffixes were present, and passing the resulting string toByte.parseByte with the specified radix.
    Parameters:
    radix - the radix used to interpret the token as a byte value
    Returns:
    thebyte scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextShort
```
public boolean hasNextShort()
```
    Returns true if the next token in this scanner's input can be interpreted as a short value in the default radix using thenextShort() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a valid short value in the default radix
    Throws:
    IllegalStateException - if this scanner is closed
  - hasNextShort
```
public boolean hasNextShort(int radix)
```
    Returns true if the next token in this scanner's input can be interpreted as a short value in the specified radix using thenextShort() method. The scanner does not advance past any input.
    Parameters:
    radix - the radix used to interpret the token as a short value
    Returns:
    true if and only if this scanner's next token is a valid short value in the specified radix
    Throws:
    IllegalStateException - if this scanner is closed
  - nextShort
```
public short nextShort()
```
    Scans the next token of the input as ashort.
    An invocation of this method of the formnextShort() behaves in exactly the same way as the invocationnextShort(radix), whereradix is the default radix of this scanner.
    Returns:
    theshort scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - nextShort
```
public short nextShort(int radix)
```
    Scans the next token of the input as ashort. This method will throwInputMismatchException if the next token cannot be translated into a valid short value as described below. If the translation is successful, the scanner advances past the input that matched.
    If the next token matches theInteger regular expression defined above then the token is converted into ashort value as if by removing all locale specific prefixes, group separators, and locale specific suffixes, then mapping non-ASCII digits into ASCII digits viaCharacter.digit, prepending a negative sign (-) if the locale specific negative prefixes and suffixes were present, and passing the resulting string toShort.parseShort with the specified radix.
    Parameters:
    radix - the radix used to interpret the token as a short value
    Returns:
    theshort scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextInt
```
public boolean hasNextInt()
```
    Returns true if the next token in this scanner's input can be interpreted as an int value in the default radix using thenextInt() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a valid int value
    Throws:
    IllegalStateException - if this scanner is closed
  - hasNextInt
```
public boolean hasNextInt(int radix)
```
    Returns true if the next token in this scanner's input can be interpreted as an int value in the specified radix using thenextInt() method. The scanner does not advance past any input.
    Parameters:
    radix - the radix used to interpret the token as an int value
    Returns:
    true if and only if this scanner's next token is a valid int value
    Throws:
    IllegalStateException - if this scanner is closed
  - nextInt
```
public int nextInt()
```
    Scans the next token of the input as anint.
    An invocation of this method of the formnextInt() behaves in exactly the same way as the invocationnextInt(radix), whereradix is the default radix of this scanner.
    Returns:
    theint scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - nextInt
```
public int nextInt(int radix)
```
    Scans the next token of the input as anint. This method will throwInputMismatchException if the next token cannot be translated into a valid int value as described below. If the translation is successful, the scanner advances past the input that matched.
    If the next token matches theInteger regular expression defined above then the token is converted into anint value as if by removing all locale specific prefixes, group separators, and locale specific suffixes, then mapping non-ASCII digits into ASCII digits viaCharacter.digit, prepending a negative sign (-) if the locale specific negative prefixes and suffixes were present, and passing the resulting string toInteger.parseInt with the specified radix.
    Parameters:
    radix - the radix used to interpret the token as an int value
    Returns:
    theint scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextLong
```
public boolean hasNextLong()
```
    Returns true if the next token in this scanner's input can be interpreted as a long value in the default radix using thenextLong() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a valid long value
    Throws:
    IllegalStateException - if this scanner is closed
  - hasNextLong
```
public boolean hasNextLong(int radix)
```
    Returns true if the next token in this scanner's input can be interpreted as a long value in the specified radix using thenextLong() method. The scanner does not advance past any input.
    Parameters:
    radix - the radix used to interpret the token as a long value
    Returns:
    true if and only if this scanner's next token is a valid long value
    Throws:
    IllegalStateException - if this scanner is closed
  - nextLong
```
public long nextLong()
```
    Scans the next token of the input as along.
    An invocation of this method of the formnextLong() behaves in exactly the same way as the invocationnextLong(radix), whereradix is the default radix of this scanner.
    Returns:
    thelong scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - nextLong
```
public long nextLong(int radix)
```
    Scans the next token of the input as along. This method will throwInputMismatchException if the next token cannot be translated into a valid long value as described below. If the translation is successful, the scanner advances past the input that matched.
    If the next token matches theInteger regular expression defined above then the token is converted into along value as if by removing all locale specific prefixes, group separators, and locale specific suffixes, then mapping non-ASCII digits into ASCII digits viaCharacter.digit, prepending a negative sign (-) if the locale specific negative prefixes and suffixes were present, and passing the resulting string toLong.parseLong with the specified radix.
    Parameters:
    radix - the radix used to interpret the token as an int value
    Returns:
    thelong scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextFloat
```
public boolean hasNextFloat()
```
    Returns true if the next token in this scanner's input can be interpreted as a float value using thenextFloat() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a valid float value
    Throws:
    IllegalStateException - if this scanner is closed
  - nextFloat
```
public float nextFloat()
```
    Scans the next token of the input as afloat. This method will throwInputMismatchException if the next token cannot be translated into a valid float value as described below. If the translation is successful, the scanner advances past the input that matched.
    If the next token matches theFloat regular expression defined above then the token is converted into afloat value as if by removing all locale specific prefixes, group separators, and locale specific suffixes, then mapping non-ASCII digits into ASCII digits viaCharacter.digit, prepending a negative sign (-) if the locale specific negative prefixes and suffixes were present, and passing the resulting string toFloat.parseFloat. If the token matches the localized NaN or infinity strings, then either "Nan" or "Infinity" is passed toFloat.parseFloat as appropriate.
    Returns:
    thefloat scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theFloat regular expression, or is out of range
    NoSuchElementException - if input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextDouble
```
public boolean hasNextDouble()
```
    Returns true if the next token in this scanner's input can be interpreted as a double value using thenextDouble() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a valid double value
    Throws:
    IllegalStateException - if this scanner is closed
  - nextDouble
```
public double nextDouble()
```
    Scans the next token of the input as adouble. This method will throwInputMismatchException if the next token cannot be translated into a valid double value. If the translation is successful, the scanner advances past the input that matched.
    If the next token matches theFloat regular expression defined above then the token is converted into adouble value as if by removing all locale specific prefixes, group separators, and locale specific suffixes, then mapping non-ASCII digits into ASCII digits viaCharacter.digit, prepending a negative sign (-) if the locale specific negative prefixes and suffixes were present, and passing the resulting string toDouble.parseDouble. If the token matches the localized NaN or infinity strings, then either "Nan" or "Infinity" is passed toDouble.parseDouble as appropriate.
    Returns:
    thedouble scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theFloat regular expression, or is out of range
    NoSuchElementException - if the input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextBigInteger
```
public boolean hasNextBigInteger()
```
    Returns true if the next token in this scanner's input can be interpreted as aBigInteger in the default radix using thenextBigInteger() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a validBigInteger
    Throws:
    IllegalStateException - if this scanner is closed
  - hasNextBigInteger
```
public boolean hasNextBigInteger(int radix)
```
    Returns true if the next token in this scanner's input can be interpreted as aBigInteger in the specified radix using thenextBigInteger() method. The scanner does not advance past any input.
    Parameters:
    radix - the radix used to interpret the token as an integer
    Returns:
    true if and only if this scanner's next token is a validBigInteger
    Throws:
    IllegalStateException - if this scanner is closed
  - nextBigInteger
```
public BigInteger nextBigInteger()
```
    Scans the next token of the input as aBigInteger.
    An invocation of this method of the formnextBigInteger() behaves in exactly the same way as the invocationnextBigInteger(radix), whereradix is the default radix of this scanner.
    Returns:
    theBigInteger scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if the input is exhausted
    IllegalStateException - if this scanner is closed
  - nextBigInteger
```
public BigInteger nextBigInteger(int radix)
```
    Scans the next token of the input as aBigInteger.
    If the next token matches theInteger regular expression defined above then the token is converted into aBigInteger value as if by removing all group separators, mapping non-ASCII digits into ASCII digits via theCharacter.digit, and passing the resulting string to theBigInteger(String, int) constructor with the specified radix.
    Parameters:
    radix - the radix used to interpret the token
    Returns:
    theBigInteger scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theInteger regular expression, or is out of range
    NoSuchElementException - if the input is exhausted
    IllegalStateException - if this scanner is closed
  - hasNextBigDecimal
```
public boolean hasNextBigDecimal()
```
    Returns true if the next token in this scanner's input can be interpreted as aBigDecimal using thenextBigDecimal() method. The scanner does not advance past any input.
    Returns:
    true if and only if this scanner's next token is a validBigDecimal
    Throws:
    IllegalStateException - if this scanner is closed
  - nextBigDecimal
```
public BigDecimal nextBigDecimal()
```
    Scans the next token of the input as aBigDecimal.
    If the next token matches theDecimal regular expression defined above then the token is converted into aBigDecimal value as if by removing all group separators, mapping non-ASCII digits into ASCII digits via theCharacter.digit, and passing the resulting string to theBigDecimal(String) constructor.
    Returns:
    theBigDecimal scanned from the input
    Throws:
    InputMismatchException - if the next token does not match theDecimal regular expression, or is out of range
    NoSuchElementException - if the input is exhausted
    IllegalStateException - if this scanner is closed
  - reset
```
public Scanner reset()
```
    Resets this scanner.
    Resetting a scanner discards all of its explicit state information which may have been changed by invocations ofuseDelimiter(java.util.regex.Pattern),useLocale(java.util.Locale), oruseRadix(int).
    An invocation of this method of the formscanner.reset() behaves in exactly the same way as the invocation
    scanner.useDelimiter("\\p{javaWhitespace}+") .useLocale(Locale.getDefault()) .useRadix(10);
    Returns:
    this scanner
    Since:
    1.6

LocalGroupSeparator	The character used to separate thousands groups,i.e., `dfs.getGroupingSeparator()`
LocalDecimalSeparator	The character used for the decimal point,i.e., `dfs.getDecimalSeparator()`
LocalPositivePrefix	The string that appears before a positive number (may be empty),i.e., `df.getPositivePrefix()`
LocalPositiveSuffix	The string that appears after a positive number (may be empty),i.e., `df.getPositiveSuffix()`
LocalNegativePrefix	The string that appears before a negative number (may be empty),i.e., `df.getNegativePrefix()`
LocalNegativeSuffix	The string that appears after a negative number (may be empty),i.e., `df.getNegativeSuffix()`
LocalNaN	The string that represents not-a-number for floating-point values,i.e., `dfs.getNaN()`
LocalInfinity	The string that represents infinity for floating-point values,i.e., `dfs.getInfinity()`

Movatterモバイル変換

Class Scanner

Localized numbers

Number syntax

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Scanner

Scanner

Scanner

Scanner

Scanner

Scanner

Scanner

Scanner

Scanner

Scanner

Method Detail

close

ioException

delimiter

useDelimiter

useDelimiter

locale

useLocale

radix

useRadix

match

toString

hasNext

next

remove

hasNext

next

hasNext

next

hasNextLine

nextLine

findInLine

findInLine

findWithinHorizon

findWithinHorizon

skip

skip

hasNextBoolean

nextBoolean

hasNextByte

hasNextByte

nextByte

nextByte

hasNextShort

hasNextShort

nextShort

nextShort

hasNextInt

hasNextInt

nextInt

nextInt

hasNextLong

hasNextLong

nextLong

nextLong

hasNextFloat

nextFloat

hasNextDouble

nextDouble

hasNextBigInteger

hasNextBigInteger

nextBigInteger

nextBigInteger

hasNextBigDecimal

nextBigDecimal

reset