CHAPTER 20: The Package java.lang

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20.4 The Class java.lang.Boolean

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 Boolean

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 Boolean

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 Boolean

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 Boolean

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:

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

20.4.5 booleanValue

public boolean booleanValue()

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

20.4.6 toString

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 (S20.1.2).

20.4.7 equals

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 (S20.1.3).

20.4.8 hashCode

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 (S20.1.4).

20.4.9 valueOf

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 getBoolean

public static boolean getBoolean(String name)

The result is true if and only if the value of the system property (S20.18.9) named by the argument is equal, ignoring case, to the string "true".