Java boolean object methods

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 .

Field Summary

Constructor Summary

Allocates a Boolean object representing the value true if the string argument is not null and is equal, ignoring case, to the string «true» .

Method Summary

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.

Returns true if and only if the system property named by the argument exists and is equal to the string «true» .

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Methods inherited from class java.lang.Object

Field Detail

TRUE

FALSE

TYPE

Constructor Detail

Boolean

public Boolean(boolean value)

Allocates a Boolean object representing the value argument. Note: It is rarely appropriate to use this constructor. Unless a new instance is required, the static factory valueOf(boolean) is generally a better choice. It is likely to yield significantly better space and time performance.

Boolean

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 .

Method Detail

parseBoolean

Parses the string argument as a boolean. 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.parseBoolean(«True») returns true .
Example: Boolean.parseBoolean(«yes») returns false .

booleanValue

public boolean booleanValue()

valueOf

Returns a Boolean instance representing the specified boolean value. If the specified boolean value is true , this method returns Boolean.TRUE ; if it is false , this method returns Boolean.FALSE . If a new Boolean instance is not required, this method should generally be used in preference to the constructor Boolean(boolean) , as this method is likely to yield significantly better space and time performance.

valueOf

Returns a Boolean with a value represented by the specified string. The Boolean returned represents a true value if the string argument is not null and is equal, ignoring case, to the string «true» .

toString

Returns a String object representing the specified boolean. If the specified boolean is true , then the string «true» will be returned, otherwise the string «false» will be returned.

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.

hashCode

public static int hashCode(boolean value)

equals

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.

getBoolean

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.

compareTo

compare

public static int compare(boolean x, boolean y)

Boolean.valueOf(x).compareTo(Boolean.valueOf(y))

logicalAnd

public static boolean logicalAnd(boolean a, boolean b)

logicalOr

public static boolean logicalOr(boolean a, boolean b)

logicalXor

public static boolean logicalXor(boolean a, boolean b)

Источник

Class Boolean

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 .

This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail.

Field Summary

Constructor Summary

Method Summary

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.

Returns true if and only if the system property named by the argument exists and is equal to, ignoring case, the string «true» .

Methods declared in class java.lang.Object

Field Details

TRUE

FALSE

TYPE

Constructor Details

Boolean

It is rarely appropriate to use this constructor. The static factory valueOf(boolean) is generally a better choice, as it is likely to yield significantly better space and time performance. Also consider using the final fields TRUE and FALSE if possible.

Boolean

It is rarely appropriate to use this constructor. Use parseBoolean(String) to convert a string to a boolean primitive, or use valueOf(String) to convert a string to a Boolean object.

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, allocates a Boolean object representing the value false .

Method Details

parseBoolean

Parses the string argument as a boolean. The boolean returned represents the value true if the string argument is not null and is equal, ignoring case, to the string «true» . Otherwise, a false value is returned, including for a null argument. Example: Boolean.parseBoolean(«True») returns true .
Example: Boolean.parseBoolean(«yes») returns false .

booleanValue

valueOf

toString

Returns a String object representing the specified boolean. If the specified boolean is true , then the string «true» will be returned, otherwise the string «false» will be returned.

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.

hashCode

equals

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.

getBoolean

Returns true 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 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.

compareTo

compare

Boolean.valueOf(x).compareTo(Boolean.valueOf(y))

logicalAnd

logicalOr

logicalXor

describeConstable

Report a bug or suggest an enhancement
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Источник