Java source Boolean

* *%w%%e% * * Copyright (c) 2006, Oracle and/or its affiliates.
 All rights reserved. * ORACLE proprietary/confidential.
 Use are subject to license terms.

* * Package Java.lang; /** * The Boolean class wraps a value of the primitive type * <code>boolean</code> in an object. An object of type * <code>Boolean</code> contains a single field whose type is * <code>boolean</c 
 Ode>. * <p> * In addition, this class provides many methods for * converting a <code>boolean</code> to a &L T;code>string</code> and A * <code>String</code> to a <code>boolean</code> 
 Other * constants and methods useful when dealing with a * &LT;CODE&GT;BOOLEAN&LT;/CODE&GT;. * @author Arthur van Hoff * @version%i%,%g% * @since JDK1.0 * * Public final class Boolean implements Java.io.Se Rializable, comparable<boolean> {/** * the <codE>boolean</code> object corresponding to the primitive * value <code>true</code>.

    */public static final Boolean true = new Boolean (true); /** * The <code>Boolean</code> object corresponding to the primitive * value <code>false< 
     /code>.

    */public static final Boolean false = new Boolean (false);
     /** * The Class object representing the primitive type Boolean.

    * * @since JDK1.1 * * public static final class<boolean> TYPE = Class.getprimitiveclass ("Boolean");
     /** * The value of the Boolean.

    * * @serial/private Final Boolean value; /** use Serialversionuid from JDK 1.0.2 for interoperability * * Private static final long Serialversionuid =-36658041

    99014368530L; /** * Allocates a <code>Boolean</code> object representing the * <code>value</code> ARG 
     Ument. * * <p><b>note: It is rarely appropriate to use this constructor.  * Unless a <i>new</i> instance is required, the static factory * {@link #valueOf (Boolean) is generally a Better choice. It is * likely to yield significantly better spaces and time performance.</b> * * @param value th
     E value of the <code>boolean</code>.
    */Public Boolean (Boolean value) {this.value = value; }/** * Allocates a <code>Boolean</code> object representing the value * <code>true</ code> If the string argument are not <code>null</code> * and are equal, ignoring case, to the string {@ 
     Code "True"}. * Otherwise, allocate a <code>Boolean</code> object representing the * value <code>false</code& gt;. examples:<p> * {@code new Boolean ("True")} produces a <tt>Boolean</tt> object * that Represen TS <tt>true</tt>.<br> * {@codE New Boolean ("Yes")} produces a <tt>Boolean</tt> object * that represents <tt>false</tt>.
     * * @param s The string to is converted to a <code>boolean</code>
    */Public Boolean (String s) {This (ToBoolean (s));  }/** * Parses the string argument as a Boolean. The <code>boolean</code> * returned represents the value <code>true</code> if the string arg Ument * are not <code>null</code> and are equal, ignoring case, to the string * {@code "true"}. <p> * Example: {@code Boolean.parseboolean ("True")} returns <tt>true</tt>.<br> * Example
     : {@code Boolean.parseboolean ("Yes")} returns &LT;TT&GT;FALSE&LT;/TT&GT;. * * @param s <code>String</code> containing the boolean * representation
  To is parsed * @return The Boolean represented by the string argument * @since 1.5   */public static Boolean Parseboolean (String s) {return ToBoolean (s);
     }/** * Returns The value of this <tt>Boolean</tt> object as a Boolean * primitive.
     * * @return The primitive <code>boolean</code> value of this object.
    * * Public boolean booleanvalue () {return value; }/** * Returns A <tt>Boolean</tt> instance representing the specified * <tt>boolean</  Tt> value. If the specified <tt>boolean</tt> value * is <tt>true</tt>, this method returns <tt>boo Lean.
     true</tt>;
     * if it is <tt>false</tt>, this method returns &LT;TT&GT;BOOLEAN.FALSE&LT;/TT&GT;. * If A new <tt>Boolean</tt> instance is isn't required, this method * should generally being used in Preferenc  E to the constructor * {@link #Boolean (Boolean)}, as this is likely to yield * significantly better spaces and time perFormance.
     * * @param b A Boolean value.
     * @return A <tt>Boolean</tt> instance representing <tt>b</tt> * @since 1.4 */public static Boolean valueof (Boolean b) {return (b)
    True:false);  }/** * Returns a <code>Boolean</code> with a value represented by the * specified string. The <code>Boolean</code> returned represents a * True value if the string argument is not <code>nul
     L</code> * and is equal, ignoring case, to the string {@code ' true '}.
     * * @param s a string.
     * @return The <code>Boolean</code> value represented by the string. */public static Boolean valueof (String s) {return ToBoolean (s)?
    True:false;  }/** * Returns a <tt>String</tt> object representing the specified * Boolean. If the specified is <code>true</code> then * the string {@code "true"}Would be returned, otherwise the * string {@code "false"} to be returned. * @param b The Boolean to is converted * @return The string representation of the specified <code>boolea n</code> * @since 1.4 */public static String toString (Boolean b) {return B?
    ' True ': ' false ';  }/** * Returns A <tt>String</tt> object representing this Boolean ' s * value. If This object represents the value <code>true</code&gt, * A string equal to {@code ' true '} is returned.
     Otherwise, a * string equal to {@code ' false '} is returned. 
     * * @return A string representation of this object. */Public String toString () {return value?
    ' True ': ' false ';
     }/** * Returns a hash code for this <tt>Boolean</tt> object. * @return The integer <tt>1231</tt> if this object represents * <tt>true</tt>; Returns the integer &LT;TT>1237</tt> If this * object represents <tt>false</tt>.
    * * public int hashcode () {return value 1231:1237; }/** * Returns <code>true</code> if and only if the argument are not * <code>null</co De> and is a <code>Boolean</code> object that * represents the same <code>boolean</code> 
     Value as this object.
     * * @param obj the object to compare with. * @return <code>true</code> If the Boolean objects represent the * same value;
     <code>false</code> otherwise. */public Boolean equals (Object obj) {if (obj instanceof Boolean) {return value = = ((Boolean) obj). Booleanvalue
	();
    return false; }/** * Returns <code>true</code> if and only if the system is named by the argument E Xists and is equal to the string * {@code "true"}. (beginning with version 1.0.2 of the
     * Java<small><sup>tm</sup></small> platform, the test of * This string was case Insensi tive.) A system property is accessible * through &LT;CODE&GT;GETPROPERTY&LT;/CODE&GT, and a method defined by the * <
     Code>system</code> class.  * <p> * If there is no. specified name, or if the specified * name is empty or null, then
     <code>false</code> is returned.
     * * @param name the system property name.
     * @return The <code>boolean</code> value of the system property. * @see Java.lang.system#getproperty (java.lang.String) * @see Java.lang.system#getproperty (java.lang.String, J
        ava.lang.String) */public static Boolean Getboolean (String name) {Boolean result = false;
        try {result = ToBoolean (System.getproperty (name));
     catch (IllegalArgumentException e) {} catch (NullPointerException e) {   return result;
     }/** * Compares this <tt>Boolean</tt> instance with another. * * @param b The <tt>Boolean</tt> instance to is compared * @return zero if this object represent s 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 Null Pointerexception If the argument is <tt>null</tt> * @see comparable * @since 1.5 * * * PU
    Blic int CompareTo (Boolean b) {return (B.value = = value 0: (value 1:-1)); 
    private static Boolean ToBoolean (String name) {return ((name!= null) && name.equalsignorecase ("true"));
 }
}