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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.util.ArrayList;
	import java.util.Collections;
	import java.util.Iterator;
	import java.util.List;

	// jmx import
	//


	/**
	* The <code>TabularType</code> class is the <i> open type</i> class
	* whose instances describe the types of {@link TabularData TabularData} values.
	*
	* @since 1.5
	*/
	public class TabularType extends OpenType<TabularData> {

	/* Serial version */
	static final long serialVersionUID = 6554071860220659261L;


	/**
	* @serial The composite type of rows
	*/
	private CompositeType rowType;

	/**
	* @serial The items used to index each row element, kept in the order the user gave
	* This is an unmodifiable {@link ArrayList}
	*/
	private List<String> indexNames;


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


	/* * Constructor * */

	/**
	* Constructs a <code>TabularType</code> instance, checking for the validity of the given parameters.
	* The validity constraints are described below for each parameter.
	* <p>
	* The Java class name of tabular data values this tabular type represents
	* (ie the class name returned by the {@link OpenType#getClassName() getClassName} method)
	* is set to the string value returned by <code>TabularData.class.getName()</code>.
	* <p>
	* @param typeName The name given to the tabular type this instance represents; cannot be a null or empty string.
	* <br>
	* @param description The human readable description of the tabular type this instance represents;
	* cannot be a null or empty string.
	* <br>
	* @param rowType The type of the row elements of tabular data values described by this tabular type instance;
	* cannot be null.
	* <br>
	* @param indexNames The names of the items the values of which are used to uniquely index each row element in the
	* tabular data values described by this tabular type instance;
	* cannot be null or empty. Each element should be an item name defined in <var>rowType</var>
	* (no null or empty string allowed).
	* It is important to note that the <b>order</b> of the item names in <var>indexNames</var>
	* is used by the methods {@link TabularData#get(java.lang.Object[]) get} and
	* {@link TabularData#remove(java.lang.Object[]) remove} of class
	* <code>TabularData</code> to match their array of values parameter to items.
	* <br>
	* @throws IllegalArgumentException if <var>rowType</var> is null,
	* or <var>indexNames</var> is a null or empty array,
	* or an element in <var>indexNames</var> is a null or empty string,
	* or <var>typeName</var> or <var>description</var> is a null or empty string.
	* <br>
	* @throws OpenDataException if an element's value of <var>indexNames</var>
	* is not an item name defined in <var>rowType</var>.
	*/
	public TabularType(String typeName,
	String description,
	CompositeType rowType,
	String[] indexNames) throws OpenDataException {

	// Check and initialize state defined by parent.
	//
	super(TabularData.class.getName(), typeName, description, false);

	// Check rowType is not null
	//
	if (rowType == null) {
	throw new IllegalArgumentException("Argument rowType cannot be null.");
	}

	// Check indexNames is neither null nor empty and does not contain any null element or empty string
	//
	checkForNullElement(indexNames, "indexNames");
	checkForEmptyString(indexNames, "indexNames");

	// Check all indexNames values are valid item names for rowType
	//
	for (int i=0; i<indexNames.length; i++) {
	if ( ! rowType.containsKey(indexNames[i]) ) {
	throw new OpenDataException("Argument's element value indexNames["+ i +"]=\""+ indexNames[i] +
	"\" is not a valid item name for rowType.");
	}
	}

	// initialize rowType
	//
	this.rowType = rowType;

	// initialize indexNames (copy content so that subsequent
	// modifs to the array referenced by the indexNames parameter
	// have no impact)
	//
	List<String> tmpList = new ArrayList<String>(indexNames.length + 1);
	for (int i=0; i<indexNames.length; i++) {
	tmpList.add(indexNames[i]);
	}
	this.indexNames = Collections.unmodifiableList(tmpList);
	}

	/**
	* Checks that Object[] arg is neither null nor empty (ie length==0)
	* and that it does not contain any null element.
	*/
	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.");
	}
	}
	}

	/**
	* Checks that String[] does not contain any empty (or blank characters only) string.
	*/
	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.");
	}
	}
	}


	/* * Tabular type specific information methods * */

	/**
	* Returns the type of the row elements of tabular data values
	* described by this <code>TabularType</code> instance.
	*
	* @return the type of each row.
	*/
	public CompositeType getRowType() {

	return rowType;
	}

	/**
	* <p>Returns, in the same order as was given to this instance's
	* constructor, an unmodifiable List of the names of the items the
	* values of which are used to uniquely index each row element of
	* tabular data values described by this <code>TabularType</code>
	* instance.</p>
	*
	* @return a List of String representing the names of the index
	* items.
	*
	*/
	public List<String> getIndexNames() {

	return indexNames;
	}

	/**
	* Tests whether <var>obj</var> is a value which could be
	* described by this <code>TabularType</code> instance.
	*
	* <p>If <var>obj</var> is null or is not an instance of
	* <code>javax.management.openmbean.TabularData</code>,
	* <code>isValue</code> returns <code>false</code>.</p>
	*
	* <p>If <var>obj</var> is an instance of
	* <code>javax.management.openmbean.TabularData</code>, say {@code
	* td}, the result is true if this {@code TabularType} is
	* <em>assignable from</em> {@link TabularData#getTabularType()
	* td.getTabularType()}, as defined in {@link
	* CompositeType#isValue CompositeType.isValue}.</p>
	*
	* @param obj the value whose open type is to be tested for
	* compatibility with this <code>TabularType</code> instance.
	*
	* @return <code>true</code> if <var>obj</var> is a value for this
	* tabular type, <code>false</code> otherwise.
	*/
	public boolean isValue(Object obj) {

	// if obj is null or not a TabularData, return false
	//
	if (!(obj instanceof TabularData))
	return false;

	// if obj is not a TabularData, return false
	//
	TabularData value = (TabularData) obj;
	TabularType valueType = value.getTabularType();
	return isAssignableFrom(valueType);
	}

	@Override
	boolean isAssignableFrom(OpenType<?> ot) {
	if (!(ot instanceof TabularType))
	return false;
	TabularType tt = (TabularType) ot;
	if (!getTypeName().equals(tt.getTypeName()) \|\|
	!getIndexNames().equals(tt.getIndexNames()))
	return false;
	return getRowType().isAssignableFrom(tt.getRowType());
	}


	/* * Methods overriden from class Object * */

	/**
	* Compares the specified <code>obj</code> parameter with this <code>TabularType</code> instance for equality.
	* <p>
	* Two <code>TabularType</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 row types are equal</li>
	* <li>they use the same index names, in the same order</li>
	* </ul>
	* <br>
	* @param obj the object to be compared for equality with this <code>TabularType</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>TabularType</code> instance.
	*/
	public boolean equals(Object obj) {

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

	// if obj is not a TabularType, return false
	//
	TabularType other;
	try {
	other = (TabularType) obj;
	} catch (ClassCastException e) {
	return false;
	}

	// Now, really test for equality between this TabularType instance and the other:
	//

	// their names should be equal
	if ( ! this.getTypeName().equals(other.getTypeName()) ) {
	return false;
	}

	// their row types should be equal
	if ( ! this.rowType.equals(other.rowType) ) {
	return false;
	}

	// their index names should be equal and in the same order (ensured by List.equals())
	if ( ! this.indexNames.equals(other.indexNames) ) {
	return false;
	}

	// All tests for equality were successfull
	//
	return true;
	}

	/**
	* Returns the hash code value for this <code>TabularType</code> instance.
	* <p>
	* The hash code of a <code>TabularType</code> instance is the sum of the hash codes
	* of all elements of information used in <code>equals</code> comparisons
	* (ie: name, row type, index names).
	* This ensures that <code> t1.equals(t2) </code> implies that <code> t1.hashCode()==t2.hashCode() </code>
	* for any two <code>TabularType</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>TabularType</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>TabularType</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();
	value += this.rowType.hashCode();
	for (String index : indexNames)
	value += index.hashCode();
	myHashCode = Integer.valueOf(value);
	}

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

	/**
	* Returns a string representation of this <code>TabularType</code> instance.
	* <p>
	* The string representation consists of the name of this class (ie <code>javax.management.openmbean.TabularType</code>),
	* the type name for this instance, the row type string representation of this instance,
	* and the index names of this instance.
	* <p>
	* As <code>TabularType</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>TabularType</code> instance
	*/
	public String toString() {

	// Calculate the string representation if it has not yet been done (ie 1st call to toString())
	//
	if (myToString == null) {
	final StringBuilder result = new StringBuilder()
	.append(this.getClass().getName())
	.append("(name=")
	.append(getTypeName())
	.append(",rowType=")
	.append(rowType.toString())
	.append(",indexNames=(");
	String sep = "";
	for (String index : indexNames) {
	result.append(sep).append(index);
	sep = ",";
	}
	result.append("))");
	myToString = result.toString();
	}

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

	}

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