/*
* @(#)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 CompositeType
class is the open type class
* whose instances describe the types of {@link CompositeData CompositeData
} 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 CompositeType
instance, checking for the validity of the given parameters.
* The validity constraints are described below for each parameter.
*
* Note that the contents of the three array parameters
* itemNames, itemDescriptions and itemTypes
* are internally copied so that any subsequent modification of these arrays by the caller of this constructor
* has no impact on the constructed CompositeType
instance.
*
* 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 CompositeData.class.getName()
.
*
* @param typeName The name given to the composite type this instance represents; cannot be a null or empty string.
*
* If obj is null or is not an instance of
* Two
* The hash code of a
* As
* The string representation consists of
* the name of this class (ie
* As
* @param description The human readable description of the composite type this instance represents;
* cannot be a null or empty string.
*
* @param itemNames The names of the items contained in the
* composite data values described by this CompositeType
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
* CompositeType
instance from another;
* the item names are internally stored sorted in ascending alphanumeric order.
*
* @param itemDescriptions The descriptions, in the same order as itemNames, of the items contained in the
* composite data values described by this CompositeType
instance;
* should be of the same size as itemNames;
* no element can be a null or empty string.
*
* @param itemTypes The open type instances, in the same order as itemNames, describing the items contained
* in the composite data values described by this CompositeType
instance;
* should be of the same size as itemNames;
* no element can be null.
*
* @throws IllegalArgumentException If typeName or description is a null or empty string,
* or itemNames or itemDescriptions or itemTypes is null,
* or any element of itemNames or itemDescriptions
* is a null or empty string,
* or any element of itemTypes is null,
* or itemNames or itemDescriptions or itemTypes
* are not of the same size.
*
* @throws OpenDataException If itemNames 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; iCompositeType
instance defines an item
* whose name is itemName.
*
* @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 itemName,
* or null
if this CompositeType
instance does not define any item
* whose name is itemName.
*
* @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 open type of the item whose name is itemName,
* or null
if this CompositeType
instance does not define any item
* whose name is itemName.
*
* @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 CompositeType
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 obj is a value which could be described by this CompositeType
instance.
* javax.management.openmbean.CompositeData
,
* isValue
returns false
.
* If obj is an instance of javax.management.openmbean.CompositeData
,
* its composite type is tested for equality with this CompositeType
instance, and isValue
* returns true
if and only if {@link #equals(java.lang.Object) equals
}
* returns true
.
*
* @param obj the value whose open type is to be tested for equality with this CompositeType
instance.
*
* @return true
if obj is a value for this composite type, false
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 obj
parameter with this CompositeType
instance for equality.
* CompositeType
instances are equal if and only if all of the following statements are true:
*
*
*
* @param obj the object to be compared for equality with this CompositeType
instance;
* if obj is null
, equals
returns false
.
*
* @return true
if the specified object is equal to this CompositeType
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 CompositeType
instance.
* CompositeType
instance is the sum of the hash codes
* of all elements of information used in equals
comparisons
* (ie: name, items names, items types).
* This ensures that t1.equals(t2)
implies that t1.hashCode()==t2.hashCode()
* for any two CompositeType
instances t1
and t2
,
* as required by the general contract of the method
* {@link Object#hashCode() Object.hashCode()}.
* CompositeType
instances are immutable, the hash code for this instance is calculated once,
* on the first call to hashCode
, and then the same value is returned for subsequent calls.
*
* @return the hash code value for this CompositeType
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 CompositeType
instance.
* javax.management.openmbean.CompositeType
), the type name for this instance,
* and the list of the items names and types string representation of this instance.
* CompositeType
instances are immutable, the string representation for this instance is calculated once,
* on the first call to toString
, and then the same value is returned for subsequent calls.
*
* @return a string representation of this CompositeType
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;
}
}