Module java.base
Package java.lang

Class Boolean

java.lang.Object
java.lang.Boolean
All Implemented Interfaces:
Serializable,Comparable<Boolean>
public final classBooleanextendsObjectimplementsSerializable,Comparable<Boolean>
The Boolean class wraps a value of the primitive typeboolean in an object. An object of typeBoolean contains a single field whose type isboolean.

In addition, this class provides many methods for converting aboolean to aString and aString to aboolean, as well as other constants and methods useful when dealing with aboolean.

Since:
1.0
See Also:
Serialized Form

  • Field Summary

    Fields 
    Modifier and TypeFieldDescription
    staticBooleanFALSE
    TheBoolean object corresponding to the primitive valuefalse.
    staticBooleanTRUE
    TheBoolean object corresponding to the primitive valuetrue.
    staticClass<Boolean>TYPE
    The Class object representing the primitive type boolean.

  • Constructor Summary

    Constructors 
    ConstructorDescription
    Boolean​(boolean value)
    Deprecated.
    It is rarely appropriate to use this constructor.
    Boolean​(String s)
    Deprecated.
    It is rarely appropriate to use this constructor.

  • Method Summary

    Modifier and TypeMethodDescription
    booleanbooleanValue()
    Returns the value of thisBoolean object as a boolean primitive.
    static intcompare​(boolean x,boolean y)
    Compares twoboolean values.
    intcompareTo​(Boolean b)
    Compares thisBoolean instance with another.
    booleanequals​(Object obj)
    Returnstrue if and only if the argument is notnull and is aBoolean object that represents the sameboolean value as this object.
    static booleangetBoolean​(String name)
    Returnstrue if and only if the system property named by the argument exists and is equal to, ignoring case, the string"true".
    inthashCode()
    Returns a hash code for thisBoolean object.
    static inthashCode​(boolean value)
    Returns a hash code for aboolean value; compatible withBoolean.hashCode().
    static booleanlogicalAnd​(boolean a,boolean b)
    Returns the result of applying the logical AND operator to the specifiedboolean operands.
    static booleanlogicalOr​(boolean a,boolean b)
    Returns the result of applying the logical OR operator to the specifiedboolean operands.
    static booleanlogicalXor​(boolean a,boolean b)
    Returns the result of applying the logical XOR operator to the specifiedboolean operands.
    static booleanparseBoolean​(String s)
    Parses the string argument as a boolean.
    StringtoString()
    Returns aString object representing this Boolean's value.
    staticStringtoString​(boolean b)
    Returns aString object representing the specified boolean.
    staticBooleanvalueOf​(boolean b)
    Returns aBoolean instance representing the specifiedboolean value.
    staticBooleanvalueOf​(String s)
    Returns aBoolean with a value represented by the specified string.

    Methods declared in class java.lang.Object

    clone,finalize,getClass,notify,notifyAll,wait,wait,wait

  • Field Details

    • TRUE

      public static final Boolean TRUE
      TheBoolean object corresponding to the primitive valuetrue.

    • FALSE

      public static final Boolean FALSE
      TheBoolean object corresponding to the primitive valuefalse.

    • TYPE

      public static final Class<Boolean> TYPE
      The Class object representing the primitive type boolean.
      Since:
      1.1

  • Constructor Details

    • Boolean

      @Deprecated(since="9")public Boolean​(boolean value)
      Deprecated.
      It is rarely appropriate to use this constructor. The static factoryvalueOf(boolean) is generally a better choice, as it is likely to yield significantly better space and time performance. Also consider using the final fieldsTRUE andFALSE if possible.
      Allocates aBoolean object representing thevalue argument.
      Parameters:
      value - the value of theBoolean.

    • Boolean

      @Deprecated(since="9")public Boolean​(String s)
      Deprecated.
      It is rarely appropriate to use this constructor. UseparseBoolean(String) to convert a string to aboolean primitive, or usevalueOf(String) to convert a string to aBoolean object.
      Allocates aBoolean object representing the valuetrue if the string argument is notnull and is equal, ignoring case, to the string"true". Otherwise, allocates aBoolean object representing the valuefalse.
      Parameters:
      s - the string to be converted to aBoolean.

  • Method Details

    • parseBoolean

      public static boolean parseBoolean​(String s)
      Parses the string argument as a boolean. Theboolean returned represents the valuetrue if the string argument is notnull and is equal, ignoring case, to the string"true". Otherwise, a false value is returned, including for a null argument.

      Example:Boolean.parseBoolean("True") returnstrue.
      Example:Boolean.parseBoolean("yes") returnsfalse.

      Parameters:
      s - theString containing the boolean representation to be parsed
      Returns:
      the boolean represented by the string argument
      Since:
      1.5

    • booleanValue

      public boolean booleanValue()
      Returns the value of thisBoolean object as a boolean primitive.
      Returns:
      the primitiveboolean value of this object.

    • valueOf

      public static Boolean valueOf​(boolean b)
      Returns aBoolean instance representing the specifiedboolean value. If the specifiedboolean value istrue, this method returnsBoolean.TRUE; if it isfalse, this method returnsBoolean.FALSE. If a newBoolean instance is not required, this method should generally be used in preference to the constructorBoolean(boolean), as this method is likely to yield significantly better space and time performance.
      Parameters:
      b - a boolean value.
      Returns:
      aBoolean instance representingb.
      Since:
      1.4

    • valueOf

      public static Boolean valueOf​(String s)
      Returns aBoolean with a value represented by the specified string. TheBoolean returned represents a true value if the string argument is notnull and is equal, ignoring case, to the string"true". Otherwise, a false value is returned, including for a null argument.
      Parameters:
      s - a string.
      Returns:
      theBoolean value represented by the string.

    • toString

      public static String toString​(boolean b)
      Returns aString object representing the specified boolean. If the specified boolean istrue, then the string"true" will be returned, otherwise the string"false" will be returned.
      Parameters:
      b - the boolean to be converted
      Returns:
      the string representation of the specifiedboolean
      Since:
      1.4

    • toString

      public String toString()
      Returns aString object representing this Boolean's value. If this object represents the valuetrue, a string equal to"true" is returned. Otherwise, a string equal to"false" is returned.
      Overrides:
      toString in class Object
      Returns:
      a string representation of this object.

    • hashCode

      public int hashCode()
      Returns a hash code for thisBoolean object.
      Overrides:
      hashCode in class Object
      Returns:
      the integer1231 if this object representstrue; returns the integer1237 if this object representsfalse.
      See Also:
      Object.equals(java.lang.Object),System.identityHashCode(java.lang.Object)

    • hashCode

      public static int hashCode​(boolean value)
      Returns a hash code for aboolean value; compatible withBoolean.hashCode().
      Parameters:
      value - the value to hash
      Returns:
      a hash code value for aboolean value.
      Since:
      1.8

    • equals

      public boolean equals​(Object obj)
      Returnstrue if and only if the argument is notnull and is aBoolean object that represents the sameboolean value as this object.
      Overrides:
      equals in class Object
      Parameters:
      obj - the object to compare with.
      Returns:
      true if the Boolean objects represent the same value;false otherwise.
      See Also:
      Object.hashCode(),HashMap

    • getBoolean

      public static boolean getBoolean​(String name)
      Returnstrue if and only if the system property named by the argument exists and is equal to, ignoring case, the string"true". A system property is accessible throughgetProperty, a method defined by theSystem class.

      If there is no property with the specified name, or if the specified name is empty or null, thenfalse is returned.

      Parameters:
      name - the system property name.
      Returns:
      theboolean value of the system property.
      Throws:
      SecurityException - for the same reasons asSystem.getProperty
      See Also:
      System.getProperty(java.lang.String),System.getProperty(java.lang.String, java.lang.String)

    • compareTo

      public int compareTo​(Boolean b)
      Compares thisBoolean instance with another.
      Specified by:
      compareTo in interface Comparable<Boolean>
      Parameters:
      b - theBoolean instance to be compared
      Returns:
      zero if this object represents the same boolean value as the argument; a positive value if this object represents true and the argument represents false; and a negative value if this object represents false and the argument represents true
      Throws:
      NullPointerException - if the argument isnull
      Since:
      1.5
      See Also:
      Comparable

    • compare

      public static int compare​(boolean x,boolean y)
      Compares twoboolean values. The value returned is identical to what would be returned by:
          Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
      Parameters:
      x - the firstboolean to compare
      y - the secondboolean to compare
      Returns:
      the value0 ifx == y; a value less than0 if!x && y; and a value greater than0 ifx && !y
      Since:
      1.7

    • logicalAnd

      public static boolean logicalAnd​(boolean a,boolean b)
      Returns the result of applying the logical AND operator to the specifiedboolean operands.
      Parameters:
      a - the first operand
      b - the second operand
      Returns:
      the logical AND ofa andb
      Since:
      1.8
      See Also:
      BinaryOperator

    • logicalOr

      public static boolean logicalOr​(boolean a,boolean b)
      Returns the result of applying the logical OR operator to the specifiedboolean operands.
      Parameters:
      a - the first operand
      b - the second operand
      Returns:
      the logical OR ofa andb
      Since:
      1.8
      See Also:
      BinaryOperator

    • logicalXor

      public static boolean logicalXor​(boolean a,boolean b)
      Returns the result of applying the logical XOR operator to the specifiedboolean operands.
      Parameters:
      a - the first operand
      b - the second operand
      Returns:
      the logical XOR ofa andb
      Since:
      1.8
      See Also:
      BinaryOperator