: Class Boolean

java.lang.Object
  |
  +--java.lang.Boolean

All Implemented Interfaces:: Serializable

public final class Boolean
extends Object
implements Serializable

The Boolean class wraps a value of the primitive type boolean in an object. An object of type Boolean contains a single field whose type is boolean.

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

Since:: JDK1.0
See Also:: Serialized Form

Field Summary

static Boolean FALSE
copy-> FALSE

The Boolean object corresponding to the primitive value false.

static Boolean TRUE
copy-> TRUE

The Boolean object corresponding to the primitive value true.

static Class TYPE
copy-> TYPE

The Class object representing the primitive type boolean.

Since:
JDK1.1

Constructor Summary

Boolean
copy-> new Boolean( )
copy-> <Boolean var> = new Boolean(<boolean value>);

Allocates a Boolean object representing the value argument.

Parameters:
value - the value of the Boolean.

Boolean
copy-> new Boolean( )
copy-> <Boolean var> = new Boolean(<String s>);

Allocates a Boolean object representing the value true if the string argument is not null and is equal, ignoring case, to the string "true". Otherwise, allocate a Boolean object representing the value false. Examples:
new Boolean("True") produces a Boolean object that represents true.
new Boolean("yes") produces a Boolean object that represents false.

Parameters:
s - the string to be converted to a Boolean.

Method Summary

boolean booleanValue()
copy-> .booleanValue()
copy-> <boolean var>=<Boolean>.booleanValue();

Returns the value of this Boolean object as a boolean primitive.

Returns:
the primitive boolean value of this object.

boolean equals(Object obj)
copy-> .equals( )
copy-> <boolean var>=<Boolean>.equals(<Object obj>);

Returns true if and only if the argument is not null and is a Boolean object that represents the same boolean 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.

static boolean getBoolean(String name)
copy-> Boolean.getBoolean( )
copy-> <boolean var>=Boolean.getBoolean(<String name>);

Returns true if and only if the system property named by the argument exists and is equal to the string "true". (Beginning with version 1.0.2 of the Java^TM platform, the test of this string is case insensitive.) A system property is accessible through getProperty, a method defined by the System class.
If there is no property with the specified name, or if the specified name is empty or null, then false is returned.

Parameters:
name - the system property name.
Returns:
the boolean value of the system property.
See Also:
System.getProperty(java.lang.String), System.getProperty(java.lang.String, java.lang.String)

int hashCode()
copy-> .hashCode()
copy-> <int var>=<Boolean>.hashCode();

Returns a hash code for this Boolean object.

Overrides:
hashCode in class Object

Returns:
the integer 1231 if this object represents true; returns the integer 1237 if this object represents false.

String toString()
copy-> .toString()
copy-> <String var>=<Boolean>.toString();

Returns a String object representing this Boolean's value. If this object represents the value true, 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.

static Boolean valueOf(String s)
copy-> Boolean.valueOf( )
copy-> <Boolean var>=Boolean.valueOf(<String s>);

Returns a Boolean with a value represented by the specified String. The Boolean returned represents the value true if the string 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.

Parameters:
s - a string.
Returns:
the Boolean value represented by the string.

Methods inherited from class java.lang.Object

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

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Field Summary
`static Boolean`	FALSE copy-> `FALSE` The `Boolean` object corresponding to the primitive value `false`.
`static Boolean`	TRUE copy-> `TRUE` The `Boolean` object corresponding to the primitive value `true`.
`static Class`	TYPE copy-> `TYPE` The Class object representing the primitive type boolean. Since: JDK1.1

Constructor Summary
Boolean copy-> `new Boolean( )` copy-> `<Boolean var> = new Boolean(<boolean value>);` Allocates a `Boolean` object representing the `value` argument. Parameters: `value` - the value of the `Boolean`.
Boolean copy-> `new Boolean( )` copy-> `<Boolean var> = new Boolean(<String s>);` Allocates a `Boolean` object representing the value `true` if the string argument is not `null` and is equal, ignoring case, to the string `"true"`. Otherwise, allocate a `Boolean` object representing the value `false`. Examples: `new Boolean("True")` produces a `Boolean` object that represents `true`. `new Boolean("yes")` produces a `Boolean` object that represents `false`. Parameters: `s` - the string to be converted to a `Boolean`.

Method Summary
`boolean`	booleanValue() copy-> `.booleanValue()` copy-> `<boolean var>=<Boolean>.booleanValue();` Returns the value of this `Boolean` object as a boolean primitive. Returns: the primitive `boolean` value of this object.
`boolean`	equals(Object obj) copy-> `.equals( )` copy-> `<boolean var>=<Boolean>.equals(<Object obj>);` Returns `true` if and only if the argument is not `null` and is a `Boolean` object that represents the same `boolean` 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.
`static boolean`	getBoolean(String name) copy-> `Boolean.getBoolean( )` copy-> `<boolean var>=Boolean.getBoolean(<String name>);` Returns `true` if and only if the system property named by the argument exists and is equal to the string `"true"`. (Beginning with version 1.0.2 of the Java^TM platform, the test of this string is case insensitive.) A system property is accessible through `getProperty`, a method defined by the `System` class. If there is no property with the specified name, or if the specified name is empty or null, then `false` is returned. Parameters: `name` - the system property name. Returns: the `boolean` value of the system property. See Also: `System.getProperty(java.lang.String)`, `System.getProperty(java.lang.String, java.lang.String)`
`int`	hashCode() copy-> `.hashCode()` copy-> `<int var>=<Boolean>.hashCode();` Returns a hash code for this `Boolean` object. Overrides: `hashCode` in class `Object` Returns: the integer `1231` if this object represents `true`; returns the integer `1237` if this object represents `false`.
`String`	toString() copy-> `.toString()` copy-> `<String var>=<Boolean>.toString();` Returns a String object representing this Boolean's value. If this object represents the value `true`, 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.
`static Boolean`	valueOf(String s) copy-> `Boolean.valueOf( )` copy-> `<Boolean var>=Boolean.valueOf(<String s>);` Returns a `Boolean` with a value represented by the specified String. The `Boolean` returned represents the value `true` if the string 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`. Parameters: `s` - a string. Returns: the `Boolean` value represented by the string.

java.lang Class Boolean

java.lang
Class Boolean