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 * 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,

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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>.

     * @param  typeName  The name given to the composite type this instance represents; cannot be a null or empty string.

     * @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 <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.

     * @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.

     * @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.

     * @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.

     * @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>

     * @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();

            }

            myHashCode = Integer.valueOf(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) {

            final StringBuilder result = new StringBuilder();

            result.append(this.getClass().getName());

            result.append("(name=");

            result.append(getTypeName());

            result.append(",items=(");

            int i=0;

            Iterator<String> k=nameToType.keySet().iterator();

            String key;

            while (k.hasNext()) {

                key = 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;

    }

}