gcc/libjava/java/lang/Boolean.java

/* Copyright (C) 1998, 1999  Cygnus Solutions

   This file is part of libgcj.

This software is copyrighted work licensed under the terms of the
Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
details.  */
 
package java.lang;

import java.io.Serializable;
 
/**
 * @author Warren Levy <warrenl@cygnus.com>
 * @date September 3, 1998.  
 */
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
 * "The Java Language Specification", ISBN 0-201-63451-1
 * plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
 * Status:  Believed complete and correct.
 */
 
public final class Boolean extends Object implements Serializable
{
  public static final Boolean FALSE = new Boolean(false);
  public static final Boolean TRUE = new Boolean(true);

  // This initialization is seemingly circular, but it is accepted
  // by javac, and is handled specially by gcc.
  public static final Class TYPE = boolean.class;

  /* The boolean value of the instance. */
  private boolean value;

  public Boolean(boolean boolVal)
  {
    value = boolVal;
  }

  public Boolean(String strVal)
  {
    value = strVal.equalsIgnoreCase("true");
  }

  public boolean booleanValue()
  {
    return value;
  }

  public boolean equals(Object obj)
  {
    /* Don't need to compare obj to null as instanceof will do this. */
    if (obj instanceof Boolean)
      return value == ((Boolean) obj).value;
    return false;
  }

  public static boolean getBoolean(String property)
  {
    /* TBD: If a security manager exists and it doesn't permit accessing
     * the property, it will throw an exception.  Should we catch it?
     */
    try
      {
	String val = System.getProperty(property);
	return val == null ? false : val.equalsIgnoreCase("true");
      }
    catch (SecurityException e)
      {
        return false;
      }
  }

  public int hashCode()
  {
    /* These values are from the Java Lang. Spec. (Sec 20.4.7).
     * TBD: They could be made private static final fields but they're only
     * used here (and shouldn't be used anywhere else), though it might be
     * useful to grep on something like JAVA_HASH_* values for us as
     * developers.
     */
    return value ? 1231 : 1237;
  }

  public String toString()
  {
    return value ? "true" : "false";
  }

  public static Boolean valueOf(String str)
  {
    /* This returns a Boolean (big B), not a boolean (little b). */
    return str.equalsIgnoreCase("true") ? TRUE : FALSE;
  }
}