/*
* Copyright (c) 2000, 2007, 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 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 <code>CompositeData</code>} values,
* nor {@link TabularData <code>TabularData</code>} 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 = new Integer(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;
}
}