/*
* @(#)CompositeType.java 3.25 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.management.openmbean;
// java import
//
import java.io.Serializable;
import java.util.Set;
import java.util.TreeMap;
import java.util.Collections;
import java.util.Iterator;
// jmx import
//
/**
* The <code>CompositeType</code> class is the <i>open type</i> class
* whose instances describe the types of {@link CompositeData <code>CompositeData</code>} values.
*
* @version 3.25 03/12/19
* @author Sun Microsystems, Inc.
*
* @since 1.5
* @since.unbundled JMX 1.1
*/
public class CompositeType
extends OpenType
implements Serializable {
/* Serial version */
static final long serialVersionUID = -5366242454346948798L;
/**
* @serial Sorted mapping of the item names to their descriptions
*/
private TreeMap nameToDescription;
/**
* @serial Sorted mapping of the item names to their open types
*/
private TreeMap nameToType;
private transient Integer myHashCode = null; // As this instance is immutable,
private transient String myToString = null; // these three values
private transient Set myNamesSet = null; // need only be calculated once.
/* *** Constructor *** */
/**
* Constructs a <code>CompositeType</code> instance, checking for the validity of the given parameters.
* The validity constraints are described below for each parameter.
* <p>
* Note that the contents of the three array parameters
* <var>itemNames</var>, <var>itemDescriptions</var> and <var>itemTypes</var>
* are internally copied so that any subsequent modification of these arrays by the caller of this constructor
* has no impact on the constructed <code>CompositeType</code> instance.
* <p>
* The Java class name of composite data values this composite type represents
* (ie the class name returned by the {@link OpenType#getClassName() getClassName} method)
* is set to the string value returned by <code>CompositeData.class.getName()</code>.
* <p>
* @param typeName The name given to the composite type this instance represents; cannot be a null or empty string.
* <br>
* @param description The human readable description of the composite type this instance represents;
* cannot be a null or empty string.
* <br>
* @param itemNames The names of the items contained in the
* composite data values described by this <code>CompositeType</code> instance;
* cannot be null and should contain at least one element; no element can be a null or empty string.
* Note that the order in which the item names are given is not important to differentiate a
* <code>CompositeType</code> instance from another;
* the item names are internally stored sorted in ascending alphanumeric order.
* <br>
* @param itemDescriptions The descriptions, in the same order as <var>itemNames</var>, of the items contained in the
* composite data values described by this <code>CompositeType</code> instance;
* should be of the same size as <var>itemNames</var>;
* no element can be a null or empty string.
* <br>
* @param itemTypes The open type instances, in the same order as <var>itemNames</var>, describing the items contained
* in the composite data values described by this <code>CompositeType</code> instance;
* should be of the same size as <var>itemNames</var>;
* no element can be null.
* <br>
* @throws IllegalArgumentException If <var>typeName</var> or <var>description</var> is a null or empty string,
* or <var>itemNames</var> or <var>itemDescriptions</var> or <var>itemTypes</var> is null,
* or any element of <var>itemNames</var> or <var>itemDescriptions</var>
* is a null or empty string,
* or any element of <var>itemTypes</var> is null,
* or <var>itemNames</var> or <var>itemDescriptions</var> or <var>itemTypes</var>
* are not of the same size.
* <br>
* @throws OpenDataException If <var>itemNames</var> contains duplicate item names
* (case sensitive, but leading and trailing whitespaces removed).
*/
public CompositeType(String typeName,
String description,
String[] itemNames,
String[] itemDescriptions,
OpenType[] itemTypes) throws OpenDataException {
// Check and construct state defined by parent
//
super(CompositeData.class.getName(), typeName, description);
// Check the 3 arrays are not null or empty (ie length==0) and that there is no null element or empty string in them
//
checkForNullElement(itemNames, "itemNames");
checkForNullElement(itemDescriptions, "itemDescriptions");
checkForNullElement(itemTypes, "itemTypes");
checkForEmptyString(itemNames, "itemNames");
checkForEmptyString(itemDescriptions, "itemDescriptions");
// Check the sizes of the 3 arrays are the same
//
if ( (itemNames.length != itemDescriptions.length) || (itemNames.length != itemTypes.length) ) {
throw new IllegalArgumentException("Array arguments itemNames[], itemDescriptions[] and itemTypes[] "+
"should be of same length (got "+ itemNames.length +", "+
itemDescriptions.length +" and "+ itemTypes.length +").");
}
// Initialize internal "names to descriptions" and "names to types" sorted maps,
// and, by doing so, check there are no duplicate item names
//
nameToDescription = new TreeMap();
nameToType = new TreeMap();
String key;
for (int i=0; i<itemNames.length; i++) {
key = itemNames[i].trim();
if (nameToDescription.containsKey(key)) {
throw new OpenDataException("Argument's element itemNames["+ i +"]=\""+ itemNames[i] +
"\" duplicates a previous item names.");
}
nameToDescription.put(key, itemDescriptions[i].trim());
nameToType.put(key, itemTypes[i]);
}
}
private static void checkForNullElement(Object[] arg, String argName) {
if ( (arg == null) || (arg.length == 0) ) {
throw new IllegalArgumentException("Argument "+ argName +"[] cannot be null or empty.");
}
for (int i=0; i<arg.length; i++) {
if (arg[i] == null) {
throw new IllegalArgumentException("Argument's element "+ argName +"["+ i +"] cannot be null.");
}
}
}
private static void checkForEmptyString(String[] arg, String argName) {
for (int i=0; i<arg.length; i++) {
if (arg[i].trim().equals("")) {
throw new IllegalArgumentException("Argument's element "+ argName +"["+ i +"] cannot be an empty string.");
}
}
}
/* *** Composite type specific information methods *** */
/**
* Returns <code>true</code> if this <code>CompositeType</code> instance defines an item
* whose name is <var>itemName</var>.
*
* @param itemName the name of the item.
*
* @return true if an item of this name is present.
*/
public boolean containsKey(String itemName) {
if (itemName == null) {
return false;
}
return nameToDescription.containsKey(itemName);
}
/**
* Returns the description of the item whose name is <var>itemName</var>,
* or <code>null</code> if this <code>CompositeType</code> instance does not define any item
* whose name is <var>itemName</var>.
*
* @param itemName the name of the item.
*
* @return the description.
*/
public String getDescription(String itemName) {
if (itemName == null) {
return null;
}
return (String) nameToDescription.get(itemName);
}
/**
* Returns the <i>open type</i> of the item whose name is <var>itemName</var>,
* or <code>null</code> if this <code>CompositeType</code> instance does not define any item
* whose name is <var>itemName</var>.
*
* @param itemName the name of the time.
*
* @return the type.
*/
public OpenType getType(String itemName) {
if (itemName == null) {
return null;
}
return (OpenType) nameToType.get(itemName);
}
/**
* Returns an unmodifiable Set view of all the item names defined by this <code>CompositeType</code> instance.
* The set's iterator will return the item names in ascending order.
*
* @return a {@link Set} of {@link String}.
*/
public Set keySet() {
// Initializes myNamesSet on first call
if (myNamesSet == null) {
myNamesSet = Collections.unmodifiableSet(nameToDescription.keySet());
}
return myNamesSet; // always return the same value
}
/**
* Tests whether <var>obj</var> is a value which could be described by this <code>CompositeType</code> instance.
* <p>
* If <var>obj</var> is null or is not an instance of <code>javax.management.openmbean.CompositeData</code>,
* <code>isValue</code> returns <code>false</code>.
* If <var>obj</var> is an instance of <code>javax.management.openmbean.CompositeData</code>,
* its composite type is tested for equality with this <code>CompositeType</code> instance, and <code>isValue</code>
* returns <code>true</code> if and only if {@link #equals(java.lang.Object) <code>equals</code>}
* returns <code>true</code>.
* <br>
* @param obj the value whose open type is to be tested for equality with this <code>CompositeType</code> instance.
*
* @return <code>true</code> if <var>obj</var> is a value for this composite type, <code>false</code> otherwise.
*/
public boolean isValue(Object obj) {
// if obj is null, return false
//
if (obj == null) {
return false;
}
// if obj is not a CompositeData, return false
//
CompositeData value;
try {
value = (CompositeData) obj;
} catch (ClassCastException e) {
return false;
}
// test value's CompositeType for equality with this CompositeType instance
//
return this.equals(value.getCompositeType());
}
/* *** Methods overriden from class Object *** */
/**
* Compares the specified <code>obj</code> parameter with this <code>CompositeType</code> instance for equality.
* <p>
* Two <code>CompositeType</code> instances are equal if and only if all of the following statements are true:
* <ul>
* <li>their type names are equal</li>
* <li>their items' names and types are equal</li>
* </ul>
* <br>
* @param obj the object to be compared for equality with this <code>CompositeType</code> instance;
* if <var>obj</var> is <code>null</code>, <code>equals</code> returns <code>false</code>.
*
* @return <code>true</code> if the specified object is equal to this <code>CompositeType</code> instance.
*/
public boolean equals(Object obj) {
// if obj is null, return false
//
if (obj == null) {
return false;
}
// if obj is not a CompositeType, return false
//
CompositeType other;
try {
other = (CompositeType) obj;
} catch (ClassCastException e) {
return false;
}
// Now, really test for equality between this CompositeType instance and the other
//
// their names should be equal
if ( ! this.getTypeName().equals(other.getTypeName()) ) {
return false;
}
// their items names and types should be equal
if ( ! this.nameToType.equals(other.nameToType) ) {
return false;
}
// All tests for equality were successfull
//
return true;
}
/**
* Returns the hash code value for this <code>CompositeType</code> instance.
* <p>
* The hash code of a <code>CompositeType</code> instance is the sum of the hash codes
* of all elements of information used in <code>equals</code> comparisons
* (ie: name, items names, items types).
* This ensures that <code> t1.equals(t2) </code> implies that <code> t1.hashCode()==t2.hashCode() </code>
* for any two <code>CompositeType</code> instances <code>t1</code> and <code>t2</code>,
* as required by the general contract of the method
* {@link Object#hashCode() Object.hashCode()}.
* <p>
* As <code>CompositeType</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>CompositeType</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) {
int value = 0;
value += this.getTypeName().hashCode();
String key;
for (Iterator k = nameToDescription.keySet().iterator(); k.hasNext(); ) {
key = (String) k.next();
value += key.hashCode();
value += this.nameToType.get(key).hashCode();
}
myHashCode = new Integer(value);
}
// return always the same hash code for this instance (immutable)
//
return myHashCode.intValue();
}
/**
* Returns a string representation of this <code>CompositeType</code> instance.
* <p>
* The string representation consists of
* the name of this class (ie <code>javax.management.openmbean.CompositeType</code>), the type name for this instance,
* and the list of the items names and types string representation of this instance.
* <p>
* As <code>CompositeType</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>CompositeType</code> instance
*/
public String toString() {
// Calculate the string representation if it has not yet been done (ie 1st call to toString())
//
if (myToString == null) {
StringBuffer result = new StringBuffer();
result.append(this.getClass().getName());
result.append("(name=");
result.append(getTypeName());
result.append(",items=(");
int i=0;
Iterator k=nameToType.keySet().iterator();
String key;
while (k.hasNext()) {
key = (String) k.next();
if (i > 0) result.append(",");
result.append("(itemName=");
result.append(key);
result.append(",itemType=");
result.append(nameToType.get(key).toString() +")");
i++;
}
result.append("))");
myToString = result.toString();
}
// return always the same string representation for this instance (immutable)
//
return myToString;
}
}
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