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	/*
	* Copyright (c) 2000, 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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/


	package javax.management.openmbean;


	// java import
	//
	import java.io.InvalidObjectException;
	import java.io.ObjectStreamException;
	import java.math.BigDecimal;
	import java.math.BigInteger;
	import java.util.Date;
	import java.util.Map;
	import java.util.HashMap;

	// jmx import
	//
	import javax.management.ObjectName;


	/**
	* The <code>SimpleType</code> class is the <i>open type</i> class whose instances describe
	* all <i>open data</i> values which are neither arrays,
	* nor {@link CompositeData CompositeData} values,
	* nor {@link TabularData TabularData} values.
	* It predefines all its possible instances as static fields, and has no public constructor.
	* <p>
	* Given a <code>SimpleType</code> instance describing values whose Java class name is <i>className</i>,
	* the internal fields corresponding to the name and description of this <code>SimpleType</code> instance
	* are also set to <i>className</i>.
	* In other words, its methods <code>getClassName</code>, <code>getTypeName</code> and <code>getDescription</code>
	* all return the same string value <i>className</i>.
	*
	* @since 1.5
	*/
	public final class SimpleType<T> extends OpenType<T> {

	/* Serial version */
	static final long serialVersionUID = 2215577471957694503L;

	// SimpleType instances.
	// IF YOU ADD A SimpleType, YOU MUST UPDATE OpenType and typeArray

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Void</code>.
	*/
	public static final SimpleType<Void> VOID =
	new SimpleType<Void>(Void.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Boolean</code>.
	*/
	public static final SimpleType<Boolean> BOOLEAN =
	new SimpleType<Boolean>(Boolean.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Character</code>.
	*/
	public static final SimpleType<Character> CHARACTER =
	new SimpleType<Character>(Character.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Byte</code>.
	*/
	public static final SimpleType<Byte> BYTE =
	new SimpleType<Byte>(Byte.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Short</code>.
	*/
	public static final SimpleType<Short> SHORT =
	new SimpleType<Short>(Short.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Integer</code>.
	*/
	public static final SimpleType<Integer> INTEGER =
	new SimpleType<Integer>(Integer.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Long</code>.
	*/
	public static final SimpleType<Long> LONG =
	new SimpleType<Long>(Long.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Float</code>.
	*/
	public static final SimpleType<Float> FLOAT =
	new SimpleType<Float>(Float.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.Double</code>.
	*/
	public static final SimpleType<Double> DOUBLE =
	new SimpleType<Double>(Double.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.lang.String</code>.
	*/
	public static final SimpleType<String> STRING =
	new SimpleType<String>(String.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.math.BigDecimal</code>.
	*/
	public static final SimpleType<BigDecimal> BIGDECIMAL =
	new SimpleType<BigDecimal>(BigDecimal.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.math.BigInteger</code>.
	*/
	public static final SimpleType<BigInteger> BIGINTEGER =
	new SimpleType<BigInteger>(BigInteger.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>java.util.Date</code>.
	*/
	public static final SimpleType<Date> DATE =
	new SimpleType<Date>(Date.class);

	/**
	* The <code>SimpleType</code> instance describing values whose
	* Java class name is <code>javax.management.ObjectName</code>.
	*/
	public static final SimpleType<ObjectName> OBJECTNAME =
	new SimpleType<ObjectName>(ObjectName.class);

	private static final SimpleType<?>[] typeArray = {
	VOID, BOOLEAN, CHARACTER, BYTE, SHORT, INTEGER, LONG, FLOAT,
	DOUBLE, STRING, BIGDECIMAL, BIGINTEGER, DATE, OBJECTNAME,
	};


	private transient Integer myHashCode = null; // As this instance is immutable, these two values
	private transient String myToString = null; // need only be calculated once.


	/* * Constructor * */

	private SimpleType(Class<T> valueClass) {
	super(valueClass.getName(), valueClass.getName(), valueClass.getName(),
	false);
	}


	/* * SimpleType specific information methods * */

	/**
	* Tests whether <var>obj</var> is a value for this
	* <code>SimpleType</code> instance. <p> This method returns
	* <code>true</code> if and only if <var>obj</var> is not null and
	* <var>obj</var>'s class name is the same as the className field
	* defined for this <code>SimpleType</code> instance (ie the class
	* name returned by the {@link OpenType#getClassName()
	* getClassName} method).
	*
	* @param obj the object to be tested.
	*
	* @return <code>true</code> if <var>obj</var> is a value for this
	* <code>SimpleType</code> instance.
	*/
	public boolean isValue(Object obj) {

	// if obj is null, return false
	//
	if (obj == null) {
	return false;
	}

	// Test if obj's class name is the same as for this instance
	//
	return this.getClassName().equals(obj.getClass().getName());
	}


	/* * Methods overriden from class Object * */

	/**
	* Compares the specified <code>obj</code> parameter with this <code>SimpleType</code> instance for equality.
	* <p>
	* Two <code>SimpleType</code> instances are equal if and only if their
	* {@link OpenType#getClassName() getClassName} methods return the same value.
	*
	* @param obj the object to be compared for equality with this <code>SimpleType</code> instance;
	* if <var>obj</var> is <code>null</code> or is not an instance of the class <code>SimpleType</code>,
	* <code>equals</code> returns <code>false</code>.
	*
	* @return <code>true</code> if the specified object is equal to this <code>SimpleType</code> instance.
	*/
	public boolean equals(Object obj) {

	/* If it weren't for readReplace(), we could replace this method
	with just:
	return (this == obj);
	*/

	if (!(obj instanceof SimpleType<?>))
	return false;

	SimpleType<?> other = (SimpleType<?>) obj;

	// Test if other's className field is the same as for this instance
	//
	return this.getClassName().equals(other.getClassName());
	}

	/**
	* Returns the hash code value for this <code>SimpleType</code> instance.
	* The hash code of a <code>SimpleType</code> instance is the the hash code of
	* the string value returned by the {@link OpenType#getClassName() getClassName} method.
	* <p>
	* As <code>SimpleType</code> instances are immutable, the hash code for this instance is calculated once,
	* on the first call to <code>hashCode</code>, and then the same value is returned for subsequent calls.
	*
	* @return the hash code value for this <code>SimpleType</code> instance
	*/
	public int hashCode() {

	// Calculate the hash code value if it has not yet been done (ie 1st call to hashCode())
	//
	if (myHashCode == null) {
	myHashCode = Integer.valueOf(this.getClassName().hashCode());
	}

	// return always the same hash code for this instance (immutable)
	//
	return myHashCode.intValue();
	}

	/**
	* Returns a string representation of this <code>SimpleType</code> instance.
	* <p>
	* The string representation consists of
	* the name of this class (ie <code>javax.management.openmbean.SimpleType</code>) and the type name
	* for this instance (which is the java class name of the values this <code>SimpleType</code> instance represents).
	* <p>
	* As <code>SimpleType</code> instances are immutable, the string representation for this instance is calculated once,
	* on the first call to <code>toString</code>, and then the same value is returned for subsequent calls.
	*
	* @return a string representation of this <code>SimpleType</code> instance
	*/
	public String toString() {

	// Calculate the string representation if it has not yet been done (ie 1st call to toString())
	//
	if (myToString == null) {
	myToString = this.getClass().getName()+ "(name="+ getTypeName() +")";
	}

	// return always the same string representation for this instance (immutable)
	//
	return myToString;
	}

	private static final Map<SimpleType<?>,SimpleType<?>> canonicalTypes =
	new HashMap<SimpleType<?>,SimpleType<?>>();
	static {
	for (int i = 0; i < typeArray.length; i++) {
	final SimpleType<?> type = typeArray[i];
	canonicalTypes.put(type, type);
	}
	}

	/**
	* Replace an object read from an {@link
	* java.io.ObjectInputStream} with the unique instance for that
	* value.
	*
	* @return the replacement object.
	*
	* @exception ObjectStreamException if the read object cannot be
	* resolved.
	*/
	public Object readResolve() throws ObjectStreamException {
	final SimpleType<?> canonical = canonicalTypes.get(this);
	if (canonical == null) {
	// Should not happen
	throw new InvalidObjectException("Invalid SimpleType: " + this);
	}
	return canonical;
	}
	}

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