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20.4 The Class java.lang.Boolean

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Objects of type Boolean represent primitive values of type boolean.

public final class Boolean {
 public static final Boolean TRUE = new Boolean(true);
 public static final Boolean FALSE = new Boolean(false);
 public Boolean(boolean value);
 public Boolean(String s);
 public String toString();
 public boolean equals(Object obj);
 public int hashCode();
 public boolean booleanValue();
 public static Boolean valueOf(String s);
 public static boolean getBoolean(String name);
}

20.4.1 public static final Boolean TRUE = new Boolean(true);

The constant value of this field is a Boolean object corresponding to the primitive value true.

20.4.2 public static final Boolean FALSE = new Boolean(false);

The constant value of this field is a Boolean object corresponding to the primitive value false.

20.4.3 public Boolean(boolean value)

This constructor initializes a newly created Boolean object so that it represents the primitive value that is the argument.

20.4.4 public Boolean(String s)

This constructor initializes a newly created Boolean object so that it represents true if and only if the argument is not null and is equal, ignoring case, to the string "true".

Examples:

newBoolean("True") produces a Boolean object that represents true.
newBoolean("yes") produces a Boolean object that represents false.

20.4.5 public boolean booleanValue()

The primitive boolean value represented by this Boolean object is returned.

20.4.6 public String toString()

If this Boolean object represents true, a string equal to "true" is returned. If this Boolean object represents false, a string equal to "false" is returned.

Overrides the toString method of Object(§20.1.2).

20.4.7 public boolean equals(Object obj)

The result is true if and only if the argument is not null and is a Boolean object that represents the same boolean value as this Boolean object.

Overrides the equals method of Object(§20.1.3).

20.4.8 public int hashCode()

If this Boolean object represents true, the integer 1231 is returned. If this Boolean object represents false, the integer 1237 is returned.

Overrides the hashCode method of Object(§20.1.4).

20.4.9 public static boolean valueOf(String s)

The result is true if and only if the argument is not null and is equal, ignoring case, to the string "true".

Example: Boolean.valueOf("True") returns true.

Example: Boolean.valueOf("yes") returns false.

20.4.10 public static boolean getBoolean(String name)

The result is true if and only if the value of the system property (§20.18.9) named by the argument is equal, ignoring case, to the string "true".

*This above all: to thine own self be true,
And it must follow, as the night the day,
Thou canst not then be false to any man.
*—William Shakespeare, Hamlet, Act I, scene iii