All Implemented Interfaces:

Serializable, Comparable<Boolean>
```
public final class Boolean
extends Object
implements Serializable, Comparable<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.

Since:

JDK1.0

See Also:
Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static Boolean`	`FALSE` The `Boolean` object corresponding to the primitive value `false`.
`static Boolean`	`TRUE` The `Boolean` object corresponding to the primitive value `true`.
`static Class<Boolean>`	`TYPE` The Class object representing the primitive type boolean.

Eerste pagina van API Java Inhoudsopgave Haut

Constructor Summary

Constructors
Constructor and Description
`Boolean(boolean value)` Allocates a `Boolean` object representing the `value` argument.
`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"`.

Eerste pagina van API Java Inhoudsopgave Haut

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`booleanValue()` Returns the value of this `Boolean` object as a boolean primitive.
`static int`	`compare(boolean x, boolean y)` Compares two `boolean` values.
`int`	`compareTo(Boolean b)` Compares this `Boolean` instance with another.
`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.
`static 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"`.
`int`	`hashCode()` Returns a hash code for this `Boolean` object.
`static boolean`	`parseBoolean(String s)` Parses the string argument as a boolean.
`String`	`toString()` Returns a `String` object representing this Boolean's value.
`static String`	`toString(boolean b)` Returns a `String` object representing the specified boolean.
`static Boolean`	`valueOf(boolean b)` Returns a `Boolean` instance representing the specified `boolean` value.
`static Boolean`	`valueOf(String s)` Returns a `Boolean` with a value represented by the specified string.

Eerste pagina van API Java Inhoudsopgave Haut

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - TRUE
```
public static final Boolean TRUE
```
    The Boolean object corresponding to the primitive value true.
  - FALSE
```
public static final Boolean FALSE
```
    The Boolean object corresponding to the primitive value false.
  - TYPE
```
public static final Class<Boolean> TYPE
```
    The Class object representing the primitive type boolean.
    
    Since:
    
    JDK1.1
- 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.
    
    Parameters:
    value - the value of the Boolean.
  - Boolean
```
public 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 Detail
  - parseBoolean
```
public static boolean parseBoolean(String s)
```
    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.
    
    Parameters:
    s - the String 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 this Boolean object as a boolean primitive.
    
    Returns:
    the primitive boolean value of this object.
  - valueOf
```
public static Boolean valueOf(boolean b)
```
    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.
    
    Parameters:
    b - a boolean value.
    
    Returns:
    a Boolean instance representing b.
    Since:
    
    1.4
  - valueOf
```
public static Boolean valueOf(String s)
```
    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".
    
    Parameters:
    s - a string.
    
    Returns:
    the Boolean value represented by the string.
  - toString
```
public static String toString(boolean b)
```
    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.
    
    Parameters:
    b - the boolean to be converted
    
    Returns:
    the string representation of the specified boolean
    Since:
    
    1.4
  - toString
```
public String 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.
  - hashCode
```
public int 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.
    See Also:
    Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)
  - equals
```
public 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.
    See Also:
    Object.hashCode(), HashMap
  - getBoolean
```
public static 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)
  - compareTo
```
public int compareTo(Boolean b)
```
    Compares this Boolean instance with another.
    
    Specified by:
    
    compareTo in interface Comparable<Boolean>
    
    Parameters:
    b - the Boolean 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 is null
    Since:
    
    1.5
    
    See Also:
    Comparable
  - compare
```
public static int compare(boolean x,
          boolean y)
```
    Compares two boolean values. The value returned is identical to what would be returned by:
```
    Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
 
```
    Parameters:
    x - the first boolean to compare
    y - the second boolean to compare
    
    Returns:
    the value 0 if x == y; a value less than 0 if !x && y; and a value greater than 0 if x && !y
    Since:
    
    1.7

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Document heeft de 11/06/2005 gemaakt, de laatste keer de 04/03/2020 gewijzigd
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Referenties

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Inhoudsopgave Haut

Class Boolean

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

TRUE

FALSE

TYPE

Constructor Detail

Boolean

Boolean

Method Detail

parseBoolean

booleanValue

valueOf

valueOf

toString

toString

hashCode

equals

getBoolean

compareTo

compare

Referenties