/*
 
* Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
 
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 
*
 
* This code is free software; you can redistribute it and/or modify it
 
* under the terms of the GNU General Public License version 2 only, as
 
* published by the Free Software Foundation.
  
Oracle designates this
 
* particular file as subject to the "Classpath" exception as provided
 
* by Oracle in the LICENSE file that accompanied this code.
 
*
 
* This code is distributed in the hope that it will be useful, but WITHOUT
 
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 
* FITNESS FOR A PARTICULAR PURPOSE.
  
See the GNU General Public License
 
* version 2 for more details (a copy is included in the LICENSE file that
 
* accompanied this code).
 
*
 
* You should have received a copy of the GNU General Public License version
 
* 2 along with this work; if not, write to the Free Software Foundation,
 
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 
*
 
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 
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*/

package java.lang;

/**
 
* The Boolean class wraps a value of the primitive type
 
* {@code boolean} in an object. An object of type
 
* {@code Boolean} contains a single field whose type is
 
* {@code boolean}.
 
* <p>
 
* In addition, this class provides many methods for
 
* converting a {@code boolean} to a {@code String} and a
 
* {@code String} to a {@code boolean}, as well as other
 
* constants and methods useful when dealing with a
 
* {@code boolean}.
 
*
 
* @author
  
Arthur van Hoff
 
* @since
   
JDK1.0
 
*/

public final class Boolean implements java.io.Serializable,
                                      
Comparable<Boolean>
{
    
/**
     
* The {@code Boolean} object corresponding to the primitive
     
* value {@code true}.
     
*/

    
public static final Boolean TRUE = new Boolean(true);

    
/**
     
* The {@code Boolean} object corresponding to the primitive
     
* value {@code false}.
     
*/

    
public static final Boolean FALSE = new Boolean(false);

    
/**
     
* The Class object representing the primitive type boolean.
     
*
     
* @since
   
JDK1.1
     
*/

    
@SuppressWarnings("unchecked")
    
public static final Class<Boolean> TYPE = (Class<Boolean>) 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 = -3665804199014368530L;

    
/**
     
* Allocates a {@code Boolean} object representing the
     
* {@code value} argument.
     
*
     
* <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 space and time performance.</b>
     
*
     
* @param
   
valuethe value of the {@code Boolean}.
     
*/

    
public Boolean(boolean value) {
        
this.value = value;
    
}

    
/**
     
* Allocates a {@code Boolean} object representing the value
     
* {@code true} if the string argument is not {@code null}
     
* and is equal, ignoring case, to the string {@code "true"}.
     
* Otherwise, allocate a {@code Boolean} object representing the
     
* value {@code false}. Examples:<p>
     
* {@code new Boolean("True")} produces a {@code Boolean} object
     
* that represents {@code true}.<br>
     
* {@code new Boolean("yes")} produces a {@code Boolean} object
     
* that represents {@code false}.
     
*
     
* @param
   
sthe string to be converted to a {@code Boolean}.
     
*/

    
public Boolean(String s) {
        
this(parseBoolean(s));
    
}

    
/**
     
* Parses the string argument as a boolean.
  
The {@code boolean}
     
* returned represents the value {@code true} if the string argument
     
* is not {@code null} and is equal, ignoring case, to the string
     
* {@code "true"}. <p>
     
* Example: {@code Boolean.parseBoolean("True")} returns {@code true}.<br>
     
* Example: {@code Boolean.parseBoolean("yes")} returns {@code false}.
     
*
     
* @param
      
s
   
the {@code String} containing the boolean
     
*
                 
representation to be parsed
     
* @returnthe boolean represented by the string argument
     
* @since 1.5
     
*/

    
public static boolean parseBoolean(String s) {
        
return ((s != null) && s.equalsIgnoreCase("true"));
    
}

    
/**
     
* Returns the value of this {@code Boolean} object as a boolean
     
* primitive.
     
*
     
* @return
  
the primitive {@code boolean} value of this object.
     
*/

    
public boolean booleanValue() {
        
return value;
    
}

    
/**
     
* Returns a {@code Boolean} instance representing the specified
     
* {@code boolean} value.
  
If the specified {@code boolean} value
     
* is {@code true}, this method returns {@code Boolean.TRUE};
     
* if it is {@code false}, this method returns {@code Boolean.FALSE}.
     
* If a new {@code Boolean} instance is not required, this method
     
* should generally be used in preference to the constructor
     
* {@link #Boolean(boolean)}, as this method is likely to yield
     
* significantly better space and time performance.
     
*
     
* @param
  
b a boolean value.
     
* @return a {@code Boolean} instance representing {@code b}.
     
* @since
  
1.4
     
*/

    
public static Boolean valueOf(boolean b) {
        
return (b ? TRUE : FALSE);
    
}

    
/**
     
* Returns a {@code Boolean} with a value represented by the
     
* specified string.
  
The {@code Boolean} returned represents a
     
* true value if the string argument is not {@code null}
     
* and is equal, ignoring case, to the string {@code "true"}.
     
*
     
* @param
   
sa string.
     
* @return
  
the {@code Boolean} value represented by the string.
     
*/

    
public static Boolean valueOf(String s) {
        
return parseBoolean(s) ? TRUE : FALSE;
    
}

    
/**
     
* Returns a {@code String} object representing the specified
     
* boolean.
  
If the specified boolean is {@code true}, then
     
* the string {@code "true"} will be returned, otherwise the
     
* string {@code "false"} will be returned.
     
*
     
* @param b the boolean to be converted
     
* @return the string representation of the specified {@code boolean}
     
* @since 1.4
     
*/

    
public static String toString(boolean b) {
        
return b ? "true" : "false";
    
}

    
/**
     
* Returns a {@code String} object representing this Boolean's
     
* value.
  
If this object represents the value {@code true},
     
* 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 {@code Boolean} object.
     
*
     
* @return
  
the integer {@code 1231} if this object represents
     
* {@code true}; returns the integer {@code 1237} if this
     
* object represents {@code false}.
     
*/

    
@Override
    
public int hashCode() {
        
return Boolean.hashCode(value);
    
}

    
/**
     
* Returns a hash code for a {@code boolean} value; compatible with
     
* {@code Boolean.hashCode()}.
     
*
     
* @param value the value to hash
     
* @return a hash code value for a {@code boolean} value.
     
* @since 1.8
     
*/

    
public static int hashCode(boolean value) {
        
return value ? 1231 : 1237;
    
}

   
/**
     
* Returns {@code true} if and only if the argument is not
     
* {@code null} and is a {@code Boolean} object that
     
* represents the same {@code boolean} value as this object.
     
*
     
* @param
   
objthe object to compare with.
     
* @return
  
{@code true} if the Boolean objects represent the
     
*
          
same value; {@code false} otherwise.
     
*/

    
public boolean equals(Object obj) {
        
if (obj instanceof Boolean) {
            
return value == ((Boolean)obj).booleanValue();
        
}
        
return false;
    
}

    
/**
     
* Returns {@code true} if and only if the system property
     
* named by the argument exists 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 is case insensitive.) A system property is accessible
     
* through {@code getProperty}, a method defined by the
     
* {@code System} class.
     
* <p>
     
* If there is no property with the specified name, or if the specified
     
* name is empty or null, then {@code false} is returned.
     
*
     
* @param
   
namethe system property name.
     
* @return
  
the {@code boolean} value of the system property.
     
* @throws
  
SecurityException for the same reasons as
     
*
          
{@link System#getProperty(String) System.getProperty}
     
* @seejava.lang.System#getProperty(java.lang.String)
     
* @seejava.lang.System#getProperty(java.lang.String, java.lang.String)
     
*/

    
public static boolean getBoolean(String name) {
        
boolean result = false;
        
try {
            
result = parseBoolean(System.getProperty(name));
        
} catch (IllegalArgumentException | NullPointerException e) {
        
}
        
return result;
    
}

    
/**
     
* Compares this {@code Boolean} instance with another.
     
*
     
* @param
   
b the {@code Boolean} instance to be compared
     
* @return
  
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 {@code null}
     
* @seeComparable
     
* @since
  
1.5
     
*/

    
public int compareTo(Boolean b) {
        
return compare(this.value, b.value);
    
}

    
/**
     
* Compares two {@code boolean} values.
     
* The value returned is identical to what would be returned by:
     
* <pre>
     
*
    
Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
     
* </pre>
     
*
     
* @param
  
x the first {@code boolean} to compare
     
* @param
  
y the second {@code boolean} to compare
     
* @return the value {@code 0} if {@code x == y};
     
*
         
a value less than {@code 0} if {@code !x && y}; and
     
*
         
a value greater than {@code 0} if {@code x && !y}
     
* @since 1.7
     
*/

    
public static int compare(boolean x, boolean y) {
        
return (x == y) ? 0 : (x ? 1 : -1);
    
}

    
/**
     
* Returns the result of applying the logical AND operator to the
     
* specified {@code boolean} operands.
     
*
     
* @param a the first operand
     
* @param b the second operand
     
* @return the logical AND of {@code a} and {@code b}
     
*
 

     
* @since 1.8
     
*/

    
public static boolean logicalAnd(boolean a, boolean b) {
        
return a && b;
    
}

    
/**
     
* Returns the result of applying the logical OR operator to the
     
* specified {@code boolean} operands.
     
*
     
* @param a the first operand
     
* @param b the second operand
     
* @return the logical OR of {@code a} and {@code b}
     
*
 

     
* @since 1.8
     
*/

    
public static boolean logicalOr(boolean a, boolean b) {
        
return a || b;
    
}

    
/**
     
* Returns the result of applying the logical XOR operator to the
     
* specified {@code boolean} operands.
     
*
     
* @param a the first operand
     
* @param b the second operand
     
* @return
  
the logical XOR of {@code a} and {@code b}
     
*
 

     
* @since 1.8
     
*/

    
public static boolean logicalXor(boolean a, boolean b) {
        
return a ^ b;
    
}
}