Class StringWriter

java.lang.Object
java.io.Writer
java.io.StringWriter
All Implemented Interfaces:
Closeable,Flushable,Appendable,AutoCloseable
public classStringWriterextendsWriter
A character stream that collects its output in a string buffer, which can then be used to construct a string.

Closing aStringWriter has no effect. The methods in this class can be called after the stream has been closed without generating anIOException.

Since:
1.1

  • Constructor Details

    • StringWriter

      public StringWriter()
      Create a new string writer using the default initial string-buffer size.

    • StringWriter

      public StringWriter(int initialSize)
      Create a new string writer using the specified initial string-buffer size.
      Parameters:
      initialSize - The number ofchar values that will fit into this buffer before it is automatically expanded
      Throws:
      IllegalArgumentException - IfinitialSize is negative

  • Method Details

    • write

      public void write(int c)
      Write a single character.
      Overrides:
      write in class Writer
      Parameters:
      c - int specifying a character to be written

    • write

      public void write(char[] cbuf, int off, int len)
      Write a portion of an array of characters.
      Specified by:
      write in class Writer
      Parameters:
      cbuf - Array of characters
      off - Offset from which to start writing characters
      len - Number of characters to write
      Throws:
      IndexOutOfBoundsException - Ifoff is negative, orlen is negative, oroff + len is negative or greater than the length of the given array

    • write

      public void write(String str)
      Write a string.
      Overrides:
      write in class Writer
      Parameters:
      str - String to be written

    • write

      public void write(String str, int off, int len)
      Write a portion of a string.
      Overrides:
      write in class Writer
      Parameters:
      str - String to be written
      off - Offset from which to start writing characters
      len - Number of characters to write
      Throws:
      IndexOutOfBoundsException - Ifoff is negative, orlen is negative, oroff + len is negative or greater than the length of the given string

    • append

      public StringWriter append(CharSequence csq)
      Appends the specified character sequence to this writer.

      An invocation of this method of the formout.append(csq) whencsq is notnull, behaves in exactly the same way as the invocation

          out.write(csq.toString())

      Depending on the specification oftoString for the character sequencecsq, the entire sequence may not be appended. For instance, invoking thetoString method of a character buffer will return a subsequence whose content depends upon the buffer's position and limit.

      Specified by:
      append in interface Appendable
      Overrides:
      append in class Writer
      Parameters:
      csq - The character sequence to append. Ifcsq isnull, then the four characters"null" are appended to this writer.
      Returns:
      This writer
      Since:
      1.5

    • append

      public StringWriter append(CharSequence csq, int start, int end)
      Appends a subsequence of the specified character sequence to this writer.

      An invocation of this method of the formout.append(csq, start, end) whencsq is notnull, behaves in exactly the same way as the invocation

          out.write(csq.subSequence(start, end).toString())

      Specified by:
      append in interface Appendable
      Overrides:
      append in class Writer
      Parameters:
      csq - The character sequence from which a subsequence will be appended. Ifcsq isnull, then characters will be appended as ifcsq contained the four characters"null".
      start - The index of the first character in the subsequence
      end - The index of the character following the last character in the subsequence
      Returns:
      This writer
      Throws:
      IndexOutOfBoundsException - Ifstart orend are negative,start is greater thanend, orend is greater thancsq.length()
      Since:
      1.5

    • append

      public StringWriter append(char c)
      Appends the specified character to this writer.

      An invocation of this method of the formout.append(c) behaves in exactly the same way as the invocation

          out.write(c)

      Specified by:
      append in interface Appendable
      Overrides:
      append in class Writer
      Parameters:
      c - The 16-bit character to append
      Returns:
      This writer
      Since:
      1.5

    • toString

      public String toString()
      Return the buffer's current value as a string.
      Overrides:
      toString in class Object
      Returns:
      a string representation of the object

    • getBuffer

      public StringBuffer getBuffer()
      Return the string buffer itself.
      Returns:
      StringBuffer holding the current buffer value.

    • flush

      public void flush()
      Flush the stream.

      Theflush method ofStringWriter does nothing.

      Specified by:
      flush in interface Flushable
      Specified by:
      flush in class Writer

    • close

      public void close() throwsIOException
      Closing aStringWriter has no effect. The methods in this class can be called after the stream has been closed without generating anIOException.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Specified by:
      close in class Writer
      Throws:
      IOException - If an I/O error occurs