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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.Set; import javax.management.Descriptor; import javax.management.DescriptorRead; // for Javadoc import javax.management.ImmutableDescriptor; import javax.management.MBeanParameterInfo; // OpenMBeanAttributeInfoSupport and this class are very similar // but can't easily be refactored because there's no multiple inheritance. // The best we can do for refactoring is to put a bunch of static methods // in OpenMBeanAttributeInfoSupport and import them here. import static javax.management.openmbean.OpenMBeanAttributeInfoSupport.*; /** * Describes a parameter used in one or more operations or * constructors of an open MBean. * * * @since 1.5 */ public class OpenMBeanParameterInfoSupport extends MBeanParameterInfo implements OpenMBeanParameterInfo { /* Serial version */ static final long serialVersionUID = -7235016873758443122L; /** * @serial The open mbean parameter's <i>open type</i> */ private OpenType<?> openType; /** * @serial The open mbean parameter's default value */ private Object defaultValue = null; /** * @serial The open mbean parameter's legal values. This {@link * Set} is unmodifiable */ private Set<?> legalValues = null; // to be constructed unmodifiable /** * @serial The open mbean parameter's min value */ private Comparable<?> minValue = null; /** * @serial The open mbean parameter's max value */ private Comparable<?> maxValue = null; // As this instance is immutable, these two values need only // be calculated once. private transient Integer myHashCode = null; // As this instance is immutable, these two values private transient String myToString = null; // need only be calculated once. /** * Constructs an {@code OpenMBeanParameterInfoSupport} instance, * which describes the parameter used in one or more operations or * constructors of a class of open MBeans, with the specified * {@code name}, {@code openType} and {@code description}. * * @param name cannot be a null or empty string. * * @param description cannot be a null or empty string. * * @param openType cannot be null. * * @throws IllegalArgumentException if {@code name} or {@code * description} are null or empty string, or {@code openType} is * null. */ public OpenMBeanParameterInfoSupport(String name, String description, OpenType<?> openType) { this(name, description, openType, (Descriptor) null); } /** * Constructs an {@code OpenMBeanParameterInfoSupport} instance, * which describes the parameter used in one or more operations or * constructors of a class of open MBeans, with the specified * {@code name}, {@code openType}, {@code description}, * and {@code descriptor}. * * <p>The {@code descriptor} can contain entries that will define * the values returned by certain methods of this class, as * explained in the <a href="package-summary.html#constraints"> * package description</a>. * * @param name cannot be a null or empty string. * * @param description cannot be a null or empty string. * * @param openType cannot be null. * * @param descriptor The descriptor for the parameter. This may be null * which is equivalent to an empty descriptor. * * @throws IllegalArgumentException if {@code name} or {@code * description} are null or empty string, or {@code openType} is * null, or the descriptor entries are invalid as described in the * <a href="package-summary.html#constraints">package * description</a>. * * @since 1.6 */ public OpenMBeanParameterInfoSupport(String name, String description, OpenType<?> openType, Descriptor descriptor) { // Construct parent's state // super(name, (openType == null) ? null : openType.getClassName(), description, ImmutableDescriptor.union(descriptor, (openType == null) ? null : openType.getDescriptor())); // Initialize this instance's specific state // this.openType = openType; descriptor = getDescriptor(); // replace null by empty this.defaultValue = valueFrom(descriptor, "defaultValue", openType); this.legalValues = valuesFrom(descriptor, "legalValues", openType); this.minValue = comparableValueFrom(descriptor, "minValue", openType); this.maxValue = comparableValueFrom(descriptor, "maxValue", openType); try { check(this); } catch (OpenDataException e) { throw new IllegalArgumentException(e.getMessage(), e); } } /** * Constructs an {@code OpenMBeanParameterInfoSupport} instance, * which describes the parameter used in one or more operations or * constructors of a class of open MBeans, with the specified * {@code name}, {@code openType}, {@code description} and {@code * defaultValue}. * * @param name cannot be a null or empty string. * * @param description cannot be a null or empty string. * * @param openType cannot be null. * * @param defaultValue must be a valid value for the {@code * openType} specified for this parameter; default value not * supported for {@code ArrayType} and {@code TabularType}; can be * null, in which case it means that no default value is set. * * @param <T> allows the compiler to check that the {@code defaultValue}, * if non-null, has the correct Java type for the given {@code openType}. * * @throws IllegalArgumentException if {@code name} or {@code * description} are null or empty string, or {@code openType} is * null. * * @throws OpenDataException if {@code defaultValue} is not a * valid value for the specified {@code openType}, or {@code * defaultValue} is non null and {@code openType} is an {@code * ArrayType} or a {@code TabularType}. */ public <T> OpenMBeanParameterInfoSupport(String name, String description, OpenType<T> openType, T defaultValue) throws OpenDataException { this(name, description, openType, defaultValue, (T[]) null); } /** * <p>Constructs an {@code OpenMBeanParameterInfoSupport} instance, * which describes the parameter used in one or more operations or * constructors of a class of open MBeans, with the specified * {@code name}, {@code openType}, {@code description}, {@code * defaultValue} and {@code legalValues}.</p> * * <p>The contents of {@code legalValues} are copied, so subsequent * modifications of the array referenced by {@code legalValues} * have no impact on this {@code OpenMBeanParameterInfoSupport} * instance.</p> * * @param name cannot be a null or empty string. * * @param description cannot be a null or empty string. * * @param openType cannot be null. * * @param defaultValue must be a valid value for the {@code * openType} specified for this parameter; default value not * supported for {@code ArrayType} and {@code TabularType}; can be * null, in which case it means that no default value is set. * * @param legalValues each contained value must be valid for the * {@code openType} specified for this parameter; legal values not * supported for {@code ArrayType} and {@code TabularType}; can be * null or empty. * * @param <T> allows the compiler to check that the {@code * defaultValue} and {@code legalValues}, if non-null, have the * correct Java type for the given {@code openType}. * * @throws IllegalArgumentException if {@code name} or {@code * description} are null or empty string, or {@code openType} is * null. * * @throws OpenDataException if {@code defaultValue} is not a * valid value for the specified {@code openType}, or one value in * {@code legalValues} is not valid for the specified {@code * openType}, or {@code defaultValue} is non null and {@code * openType} is an {@code ArrayType} or a {@code TabularType}, or * {@code legalValues} is non null and non empty and {@code * openType} is an {@code ArrayType} or a {@code TabularType}, or * {@code legalValues} is non null and non empty and {@code * defaultValue} is not contained in {@code legalValues}. */ public <T> OpenMBeanParameterInfoSupport(String name, String description, OpenType<T> openType, T defaultValue, T[] legalValues) throws OpenDataException { this(name, description, openType, defaultValue, legalValues, null, null); } /** * Constructs an {@code OpenMBeanParameterInfoSupport} instance, * which describes the parameter used in one or more operations or * constructors of a class of open MBeans, with the specified * {@code name}, {@code openType}, {@code description}, {@code * defaultValue}, {@code minValue} and {@code maxValue}. * * It is possible to specify minimal and maximal values only for * an open type whose values are {@code Comparable}. * * @param name cannot be a null or empty string. * * @param description cannot be a null or empty string. * * @param openType cannot be null. * * @param defaultValue must be a valid value for the {@code * openType} specified for this parameter; default value not * supported for {@code ArrayType} and {@code TabularType}; can be * null, in which case it means that no default value is set. * * @param minValue must be valid for the {@code openType} * specified for this parameter; can be null, in which case it * means that no minimal value is set. * * @param maxValue must be valid for the {@code openType} * specified for this parameter; can be null, in which case it * means that no maximal value is set. * * @param <T> allows the compiler to check that the {@code * defaultValue}, {@code minValue}, and {@code maxValue}, if * non-null, have the correct Java type for the given {@code * openType}. * * @throws IllegalArgumentException if {@code name} or {@code * description} are null or empty string, or {@code openType} is * null. * * @throws OpenDataException if {@code defaultValue}, {@code * minValue} or {@code maxValue} is not a valid value for the * specified {@code openType}, or {@code defaultValue} is non null * and {@code openType} is an {@code ArrayType} or a {@code * TabularType}, or both {@code minValue} and {@code maxValue} are * non-null and {@code minValue.compareTo(maxValue) > 0} is {@code * true}, or both {@code defaultValue} and {@code minValue} are * non-null and {@code minValue.compareTo(defaultValue) > 0} is * {@code true}, or both {@code defaultValue} and {@code maxValue} * are non-null and {@code defaultValue.compareTo(maxValue) > 0} * is {@code true}. */ public <T> OpenMBeanParameterInfoSupport(String name, String description, OpenType<T> openType, T defaultValue, Comparable<T> minValue, Comparable<T> maxValue) throws OpenDataException { this(name, description, openType, defaultValue, null, minValue, maxValue); } private <T> OpenMBeanParameterInfoSupport(String name, String description, OpenType<T> openType, T defaultValue, T[] legalValues, Comparable<T> minValue, Comparable<T> maxValue) throws OpenDataException { super(name, (openType == null) ? null : openType.getClassName(), description, makeDescriptor(openType, defaultValue, legalValues, minValue, maxValue)); this.openType = openType; Descriptor d = getDescriptor(); this.defaultValue = defaultValue; this.minValue = minValue; this.maxValue = maxValue; // We already converted the array into an unmodifiable Set // in the descriptor. this.legalValues = (Set<?>) d.getFieldValue("legalValues"); check(this); } /** * An object serialized in a version of the API before Descriptors were * added to this class will have an empty or null Descriptor. * For consistency with our * behavior in this version, we must replace the object with one * where the Descriptors reflect the same values of openType, defaultValue, * etc. **/ private Object readResolve() { if (getDescriptor().getFieldNames().length == 0) { // This noise allows us to avoid "unchecked" warnings without // having to suppress them explicitly. OpenType<Object> xopenType = cast(openType); Set<Object> xlegalValues = cast(legalValues); Comparable<Object> xminValue = cast(minValue); Comparable<Object> xmaxValue = cast(maxValue); return new OpenMBeanParameterInfoSupport(name, description, openType, makeDescriptor(xopenType, defaultValue, xlegalValues, xminValue, xmaxValue)); } else return this; } /** * Returns the open type for the values of the parameter described * by this {@code OpenMBeanParameterInfoSupport} instance. */ public OpenType<?> getOpenType() { return openType; } /** * Returns the default value for the parameter described by this * {@code OpenMBeanParameterInfoSupport} instance, if specified, * or {@code null} otherwise. */ public Object getDefaultValue() { // Special case for ArrayType and TabularType // [JF] TODO: clone it so that it cannot be altered, // [JF] TODO: if we decide to support defaultValue as an array itself. // [JF] As of today (oct 2000) it is not supported so // defaultValue is null for arrays. Nothing to do. return defaultValue; } /** * Returns an unmodifiable Set of legal values for the parameter * described by this {@code OpenMBeanParameterInfoSupport} * instance, if specified, or {@code null} otherwise. */ public Set<?> getLegalValues() { // Special case for ArrayType and TabularType // [JF] TODO: clone values so that they cannot be altered, // [JF] TODO: if we decide to support LegalValues as an array itself. // [JF] As of today (oct 2000) it is not supported so // legalValues is null for arrays. Nothing to do. // Returns our legalValues Set (set was constructed unmodifiable) return (legalValues); } /** * Returns the minimal value for the parameter described by this * {@code OpenMBeanParameterInfoSupport} instance, if specified, * or {@code null} otherwise. */ public Comparable<?> getMinValue() { // Note: only comparable values have a minValue, so that's not // the case of arrays and tabulars (always null). return minValue; } /** * Returns the maximal value for the parameter described by this * {@code OpenMBeanParameterInfoSupport} instance, if specified, * or {@code null} otherwise. */ public Comparable<?> getMaxValue() { // Note: only comparable values have a maxValue, so that's not // the case of arrays and tabulars (always null). return maxValue; } /** * Returns {@code true} if this {@code * OpenMBeanParameterInfoSupport} instance specifies a non-null * default value for the described parameter, {@code false} * otherwise. */ public boolean hasDefaultValue() { return (defaultValue != null); } /** * Returns {@code true} if this {@code * OpenMBeanParameterInfoSupport} instance specifies a non-null * set of legal values for the described parameter, {@code false} * otherwise. */ public boolean hasLegalValues() { return (legalValues != null); } /** * Returns {@code true} if this {@code * OpenMBeanParameterInfoSupport} instance specifies a non-null * minimal value for the described parameter, {@code false} * otherwise. */ public boolean hasMinValue() { return (minValue != null); } /** * Returns {@code true} if this {@code * OpenMBeanParameterInfoSupport} instance specifies a non-null * maximal value for the described parameter, {@code false} * otherwise. */ public boolean hasMaxValue() { return (maxValue != null); } /** * Tests whether {@code obj} is a valid value for the parameter * described by this {@code OpenMBeanParameterInfo} instance. * * @param obj the object to be tested. * * @return {@code true} if {@code obj} is a valid value * for the parameter described by this * {@code OpenMBeanParameterInfo} instance, * {@code false} otherwise. */ public boolean isValue(Object obj) { return OpenMBeanAttributeInfoSupport.isValue(this, obj); // compiler bug? should be able to omit class name here // also below in toString and hashCode } /* *** Commodity methods from java.lang.Object *** */ /** * <p>Compares the specified {@code obj} parameter with this {@code * OpenMBeanParameterInfoSupport} instance for equality.</p> * * <p>Returns {@code true} if and only if all of the following * statements are true: * * <ul> * <li>{@code obj} is non null,</li> * <li>{@code obj} also implements the {@code OpenMBeanParameterInfo} * interface,</li> * <li>their names are equal</li> * <li>their open types are equal</li> * <li>their default, min, max and legal values are equal.</li> * </ul> * This ensures that this {@code equals} method works properly for * {@code obj} parameters which are different implementations of * the {@code OpenMBeanParameterInfo} interface. * * <p>If {@code obj} also implements {@link DescriptorRead}, then its * {@link DescriptorRead#getDescriptor() getDescriptor()} method must * also return the same value as for this object.</p> * * @param obj the object to be compared for equality with this * {@code OpenMBeanParameterInfoSupport} instance. * * @return {@code true} if the specified object is equal to this * {@code OpenMBeanParameterInfoSupport} instance. */ public boolean equals(Object obj) { if (!(obj instanceof OpenMBeanParameterInfo)) return false; OpenMBeanParameterInfo other = (OpenMBeanParameterInfo) obj; return equal(this, other); } /** * <p>Returns the hash code value for this {@code * OpenMBeanParameterInfoSupport} instance.</p> * * <p>The hash code of an {@code OpenMBeanParameterInfoSupport} * instance is the sum of the hash codes of all elements of * information used in {@code equals} comparisons (ie: its name, * its <i>open type</i>, its default, min, max and legal * values, and its Descriptor). * * <p>This ensures that {@code t1.equals(t2)} implies that {@code * t1.hashCode()==t2.hashCode()} for any two {@code * OpenMBeanParameterInfoSupport} instances {@code t1} and {@code * t2}, as required by the general contract of the method {@link * Object#hashCode() Object.hashCode()}. * * <p>However, note that another instance of a class implementing * the {@code OpenMBeanParameterInfo} interface may be equal to * this {@code OpenMBeanParameterInfoSupport} instance as defined * by {@link #equals(java.lang.Object)}, but may have a different * hash code if it is calculated differently. * * <p>As {@code OpenMBeanParameterInfoSupport} instances are * immutable, the hash code for this instance is calculated once, * on the first call to {@code hashCode}, and then the same value * is returned for subsequent calls. * * @return the hash code value for this {@code * OpenMBeanParameterInfoSupport} instance */ public int hashCode() { // Calculate the hash code value if it has not yet been done // (ie 1st call to hashCode()) // if (myHashCode == null) myHashCode = OpenMBeanAttributeInfoSupport.hashCode(this); // return always the same hash code for this instance (immutable) // return myHashCode.intValue(); } /** * Returns a string representation of this * {@code OpenMBeanParameterInfoSupport} instance. * <p> * The string representation consists of the name of this class (i.e. * {@code javax.management.openmbean.OpenMBeanParameterInfoSupport}), * the string representation of the name and open type of the described * parameter, the string representation of its default, min, max and legal * values and the string representation of its descriptor. * <p> * As {@code OpenMBeanParameterInfoSupport} instances are immutable, * the string representation for this instance is calculated once, * on the first call to {@code toString}, and then the same value * is returned for subsequent calls. * * @return a string representation of this * {@code OpenMBeanParameterInfoSupport} instance. */ public String toString() { // Calculate the string value if it has not yet been done (ie // 1st call to toString()) // if (myToString == null) myToString = OpenMBeanAttributeInfoSupport.toString(this); // return always the same string representation for this // instance (immutable) // return myToString; } }