/*
* @(#)TabularType.java 3.22 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.List;
import java.util.Iterator;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.Collections;
// jmx import
//
/**
* The TabularType
class is the open type class
* whose instances describe the types of {@link TabularData TabularData
} values.
*
* @version 3.22 03/12/19
* @author Sun Microsystems, Inc.
*
* @since 1.5
* @since.unbundled JMX 1.1
*/
public class TabularType
extends OpenType
implements Serializable {
/* 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 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 TabularType
instance, checking for the validity of the given parameters.
* The validity constraints are described below for each parameter.
*
* 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 TabularData.class.getName()
.
*
* @param typeName The name given to the tabular type this instance represents; cannot be a null or empty string.
* 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
* 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 tabular type this instance represents;
* cannot be a null or empty string.
*
* @param rowType The type of the row elements of tabular data values described by this tabular type instance;
* cannot be null.
*
* @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 rowType
* (no null or empty string allowed).
* It is important to note that the order of the item names in indexNames
* is used by the methods {@link TabularData#get(java.lang.Object[]) get
} and
* {@link TabularData#remove(java.lang.Object[]) remove
} of class
* TabularData
to match their array of values parameter to items.
*
* @throws IllegalArgumentException if rowType is null,
* or indexNames is a null or empty array,
* or an element in indexNames is a null or empty string,
* or typeName or description is a null or empty string.
*
* @throws OpenDataException if an element's value of indexNames
* is not an item name defined in rowType.
*/
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);
// 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; iTabularType
* instance.TabularType
instance.
* javax.management.openmbean.TabularData
,
* isValue
returns false
.
* If obj is an instance of javax.management.openmbean.TabularData
,
* its tabular type is tested for equality with this tabular type 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 TabularType
instance.
*
* @return true
if obj is a value for this tabular type, false
otherwise.
*/
public boolean isValue(Object obj) {
// if obj is null, return false
//
if (obj == null) {
return false;
}
// if obj is not a TabularData, return false
//
TabularData value;
try {
value = (TabularData) obj;
} catch (ClassCastException e) {
return false;
}
// test value's TabularType for equality with this TabularType instance
//
return this.equals(value.getTabularType());
}
/* *** Methods overriden from class Object *** */
/**
* Compares the specified obj
parameter with this TabularType
instance for equality.
* TabularType
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 TabularType
instance;
* if obj is null
, equals
returns false
.
*
* @return true
if the specified object is equal to this TabularType
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 TabularType
instance.
* TabularType
instance is the sum of the hash codes
* of all elements of information used in equals
comparisons
* (ie: name, row type, index names).
* This ensures that t1.equals(t2)
implies that t1.hashCode()==t2.hashCode()
* for any two TabularType
instances t1
and t2
,
* as required by the general contract of the method
* {@link Object#hashCode() Object.hashCode()}.
* TabularType
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 TabularType
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 (Iterator k = indexNames.iterator(); k.hasNext(); ) {
value += k.next().hashCode();
}
myHashCode = new Integer(value);
}
// return always the same hash code for this instance (immutable)
//
return myHashCode.intValue();
}
/**
* Returns a string representation of this TabularType
instance.
* javax.management.openmbean.TabularType
),
* the type name for this instance, the row type string representation of this instance,
* and the index names of this instance.
* TabularType
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 TabularType
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()
.append(this.getClass().getName())
.append("(name=")
.append(getTypeName())
.append(",rowType=")
.append(rowType.toString())
.append(",indexNames=(");
int i=0;
Iterator k = indexNames.iterator();
while( k.hasNext() ) {
if (i > 0) result.append(",");
result.append(k.next().toString());
i++;
}
result.append("))");
myToString = result.toString();
}
// return always the same string representation for this instance (immutable)
//
return myToString;
}
}