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/*
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* 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.
*
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package javax.management.openmbean;
// java import
//
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 CompositeData} values.
*
*
* @since 1.5
*/
public class CompositeType extends OpenType<CompositeData> {
/* Serial version */
static final long serialVersionUID = -5366242454346948798L;
/**
* @serial Sorted mapping of the item names to their descriptions
*/
private TreeMap<String,String> nameToDescription;
/**
* @serial Sorted mapping of the item names to their open types
*/
private TreeMap<String,OpenType<?>> nameToType;
/* As this instance is immutable, following three values need only
* be calculated once. */
private transient Integer myHashCode = null;
private transient String myToString = null;
private transient Set<String> myNamesSet = null;
/* *** 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 null or an 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, false);
// 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<String,String>();
nameToType = new TreeMap<String,OpenType<?>>();
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 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<String> 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>.</p>
*
* <p>If <var>obj</var> is an instance of
* <code>javax.management.openmbean.CompositeData</code>, then let
* {@code ct} be its {@code CompositeType} as returned by {@link
* CompositeData#getCompositeType()}. The result is true if
* {@code this} is <em>assignable from</em> {@code ct}. This
* means that:</p>
*
* <ul>
* <li>{@link #getTypeName() this.getTypeName()} equals
* {@code ct.getTypeName()}, and
* <li>there are no item names present in {@code this} that are
* not also present in {@code ct}, and
* <li>for every item in {@code this}, its type is assignable from
* the type of the corresponding item in {@code ct}.
* </ul>
*
* <p>A {@code TabularType} is assignable from another {@code
* TabularType} if they have the same {@linkplain
* TabularType#getTypeName() typeName} and {@linkplain
* TabularType#getIndexNames() index name list}, and the
* {@linkplain TabularType#getRowType() row type} of the first is
* assignable from the row type of the second.
*
* <p>An {@code ArrayType} is assignable from another {@code
* ArrayType} if they have the same {@linkplain
* ArrayType#getDimension() dimension}; and both are {@linkplain
* ArrayType#isPrimitiveArray() primitive arrays} or neither is;
* and the {@linkplain ArrayType#getElementOpenType() element
* type} of the first is assignable from the element type of the
* second.
*
* <p>In every other case, an {@code OpenType} is assignable from
* another {@code OpenType} only if they are equal.</p>
*
* <p>These rules mean that extra items can be added to a {@code
* CompositeData} without making it invalid for a {@code CompositeType}
* that does not have those items.</p>
*
* @param obj the value whose open type is to be tested for compatibility
* 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 or not CompositeData, return false
//
if (!(obj instanceof CompositeData)) {
return false;
}
// if obj is not a CompositeData, return false
//
CompositeData value = (CompositeData) obj;
// test value's CompositeType is assignable to this CompositeType instance
//
CompositeType valueType = value.getCompositeType();
return this.isAssignableFrom(valueType);
}
/**
* Tests whether values of the given type can be assigned to this
* open type. The result is true if the given type is also a
* CompositeType with the same name ({@link #getTypeName()}), and
* every item in this type is also present in the given type with
* the same name and assignable type. There can be additional
* items in the given type, which are ignored.
*
* @param ot the type to be tested.
*
* @return true if {@code ot} is assignable to this open type.
*/
@Override
boolean isAssignableFrom(OpenType<?> ot) {
if (!(ot instanceof CompositeType))
return false;
CompositeType ct = (CompositeType) ot;
if (!ct.getTypeName().equals(getTypeName()))
return false;
for (String key : keySet()) {
OpenType<?> otItemType = ct.getType(key);
OpenType<?> thisItemType = getType(key);
if (otItemType == null ||
!thisItemType.isAssignableFrom(otItemType))
return false;
}
return true;
}
/* *** 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();
for (String key : nameToDescription.keySet()) {
value += key.hashCode();
value += this.nameToType.get(key).hashCode();
}
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