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/* * Copyright (c) 2000, 2017, 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. */ /* * @author IBM Corp. * * Copyright IBM Corp. 1999-2000. All rights reserved. */ package javax.management.modelmbean; import static com.sun.jmx.defaults.JmxProperties.MODELMBEAN_LOGGER; import com.sun.jmx.mbeanserver.GetPropertyAction; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.ObjectStreamField; import java.lang.reflect.Method; import java.security.AccessController; import java.lang.System.Logger.Level; import javax.management.Descriptor; import javax.management.DescriptorKey; import javax.management.DescriptorAccess; import javax.management.MBeanAttributeInfo; import javax.management.RuntimeOperationsException; /** * <p>The ModelMBeanAttributeInfo object describes an attribute of the ModelMBean. * It is a subclass of MBeanAttributeInfo with the addition of an associated Descriptor * and an implementation of the DescriptorAccess interface.</p> * * <P id="descriptor"> * The fields in the descriptor are defined, but not limited to, the following. * Note that when the Type in this table is Number, a String that is the decimal * representation of a Long can also be used.</P> * * <table class="striped"> * <caption style="display:none">ModelMBeanAttributeInfo Fields</caption> * <thead> * <tr><th scope="col">Name</th><th scope="col">Type</th><th scope="col">Meaning</th></tr> * </thead> * <tbody style="text-align:left"> * <tr><th scope="row">name</th><td>String</td> * <td>Attribute name.</td></tr> * <tr><th scope="row">descriptorType</th><td>String</td> * <td>Must be "attribute".</td></tr> * <tr id="value-field"><th scope="row">value</th><td>Object</td> * <td>Current (cached) value for attribute.</td></tr> * <tr><th scope="row">default</th><td>Object</td> * <td>Default value for attribute.</td></tr> * <tr><th scope="row">displayName</th><td>String</td> * <td>Name of attribute to be used in displays.</td></tr> * <tr><th scope="row">getMethod</th><td>String</td> * <td>Name of operation descriptor for get method.</td></tr> * <tr><th scope="row">setMethod</th><td>String</td> * <td>Name of operation descriptor for set method.</td></tr> * <tr><th scope="row">protocolMap</th><td>Descriptor</td> * <td>See the section "Protocol Map Support" in the JMX specification * document. Mappings must be appropriate for the attribute and entries * can be updated or augmented at runtime.</td></tr> * <tr><th scope="row">persistPolicy</th><td>String</td> * <td>One of: OnUpdate|OnTimer|NoMoreOftenThan|OnUnregister|Always|Never. * See the section "MBean Descriptor Fields" in the JMX specification * document.</td></tr> * <tr><th scope="row">persistPeriod</th><td>Number</td> * <td>Frequency of persist cycle in seconds. Used when persistPolicy is * "OnTimer" or "NoMoreOftenThan".</td></tr> * <tr><th scope="row">currencyTimeLimit</th><td>Number</td> * <td>How long <a href="#value-field">value</a> is valid: <0 never, * =0 always, >0 seconds.</td></tr> * <tr><th scope="row">lastUpdatedTimeStamp</th><td>Number</td> * <td>When <a href="#value-field">value</a> was set.</td></tr> * <tr><th scope="row">visibility</th><td>Number</td> * <td>1-4 where 1: always visible, 4: rarely visible.</td></tr> * <tr><th scope="row">presentationString</th><td>String</td> * <td>XML formatted string to allow presentation of data.</td></tr> * </tbody> * </table> * * <p>The default descriptor contains the name, descriptorType and displayName * fields. The default value of the name and displayName fields is the name of * the attribute.</p> * * <p><b>Note:</b> because of inconsistencies in previous versions of * this specification, it is recommended not to use negative or zero * values for <code>currencyTimeLimit</code>. To indicate that a * cached value is never valid, omit the * <code>currencyTimeLimit</code> field. To indicate that it is * always valid, use a very large number for this field.</p> * * <p>The <b>serialVersionUID</b> of this class is <code>6181543027787327345L</code>. * * @since 1.5 */ @SuppressWarnings("serial") // serialVersionUID is not constant public class ModelMBeanAttributeInfo extends MBeanAttributeInfo implements DescriptorAccess { // Serialization compatibility stuff: // Two serial forms are supported in this class. The selected form depends // on system property "jmx.serial.form": // - "1.0" for JMX 1.0 // - any other value for JMX 1.1 and higher // // Serial version for old serial form private static final long oldSerialVersionUID = 7098036920755973145L; // // Serial version for new serial form private static final long newSerialVersionUID = 6181543027787327345L; // // Serializable fields in old serial form private static final ObjectStreamField[] oldSerialPersistentFields = { new ObjectStreamField("attrDescriptor", Descriptor.class), new ObjectStreamField("currClass", String.class) }; // // Serializable fields in new serial form private static final ObjectStreamField[] newSerialPersistentFields = { new ObjectStreamField("attrDescriptor", Descriptor.class) }; // // Actual serial version and serial form private static final long serialVersionUID; /** * @serialField attrDescriptor Descriptor The {@link Descriptor} * containing the metadata corresponding to this attribute */ private static final ObjectStreamField[] serialPersistentFields; private static boolean compat = false; static { try { GetPropertyAction act = new GetPropertyAction("jmx.serial.form"); String form = AccessController.doPrivileged(act); compat = (form != null && form.equals("1.0")); } catch (Exception e) { // OK: No compat with 1.0 } if (compat) { serialPersistentFields = oldSerialPersistentFields; serialVersionUID = oldSerialVersionUID; } else { serialPersistentFields = newSerialPersistentFields; serialVersionUID = newSerialVersionUID; } } // // END Serialization compatibility stuff /** * @serial The {@link Descriptor} containing the metadata corresponding to * this attribute */ private Descriptor attrDescriptor = validDescriptor(null); private final static String currClass = "ModelMBeanAttributeInfo"; /** * Constructs a ModelMBeanAttributeInfo object with a default * descriptor. The {@link Descriptor} of the constructed * object will include fields contributed by any annotations * on the {@code Method} objects that contain the {@link * DescriptorKey} meta-annotation. * * @param name The name of the attribute. * @param description A human readable description of the attribute. Optional. * @param getter The method used for reading the attribute value. * May be null if the property is write-only. * @param setter The method used for writing the attribute value. * May be null if the attribute is read-only. * @exception javax.management.IntrospectionException There is a consistency * problem in the definition of this attribute. * */ public ModelMBeanAttributeInfo(String name, String description, Method getter, Method setter) throws javax.management.IntrospectionException { super(name, description, getter, setter); if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, "ModelMBeanAttributeInfo(" + "String,String,Method,Method) " + "Entry " + name); } attrDescriptor = validDescriptor(null); // put getter and setter methods in operations list // create default descriptor } /** * Constructs a ModelMBeanAttributeInfo object. The {@link * Descriptor} of the constructed object will include fields * contributed by any annotations on the {@code Method} * objects that contain the {@link DescriptorKey} * meta-annotation. * * @param name The name of the attribute. * @param description A human readable description of the attribute. Optional. * @param getter The method used for reading the attribute value. * May be null if the property is write-only. * @param setter The method used for writing the attribute value. * May be null if the attribute is read-only. * @param descriptor An instance of Descriptor containing the * appropriate metadata for this instance of the Attribute. If * it is null, then a default descriptor will be created. If * the descriptor does not contain the field "displayName" this field is added * in the descriptor with its default value. * @exception javax.management.IntrospectionException There is a consistency * problem in the definition of this attribute. * @exception RuntimeOperationsException Wraps an * IllegalArgumentException. The descriptor is invalid, or descriptor * field "name" is not equal to name parameter, or descriptor field * "descriptorType" is not equal to "attribute". * */ public ModelMBeanAttributeInfo(String name, String description, Method getter, Method setter, Descriptor descriptor) throws javax.management.IntrospectionException { super(name, description, getter, setter); // put getter and setter methods in operations list if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, "ModelMBeanAttributeInfo(" + "String,String,Method,Method,Descriptor) " + "Entry " + name); } attrDescriptor = validDescriptor(descriptor); } /** * Constructs a ModelMBeanAttributeInfo object with a default descriptor. * * @param name The name of the attribute * @param type The type or class name of the attribute * @param description A human readable description of the attribute. * @param isReadable True if the attribute has a getter method, false otherwise. * @param isWritable True if the attribute has a setter method, false otherwise. * @param isIs True if the attribute has an "is" getter, false otherwise. * */ public ModelMBeanAttributeInfo(String name, String type, String description, boolean isReadable, boolean isWritable, boolean isIs) { super(name, type, description, isReadable, isWritable, isIs); // create default descriptor if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, ModelMBeanAttributeInfo.class.getName(), "ModelMBeanAttributeInfo(" + "String,String,String,boolean,boolean,boolean)", "Entry", name); } attrDescriptor = validDescriptor(null); } /** * Constructs a ModelMBeanAttributeInfo object. * * @param name The name of the attribute * @param type The type or class name of the attribute * @param description A human readable description of the attribute. * @param isReadable True if the attribute has a getter method, false otherwise. * @param isWritable True if the attribute has a setter method, false otherwise. * @param isIs True if the attribute has an "is" getter, false otherwise. * @param descriptor An instance of Descriptor containing the * appropriate metadata for this instance of the Attribute. If * it is null then a default descriptor will be created. If * the descriptor does not contain the field "displayName" this field * is added in the descriptor with its default value. * @exception RuntimeOperationsException Wraps an * IllegalArgumentException. The descriptor is invalid, or descriptor * field "name" is not equal to name parameter, or descriptor field * "descriptorType" is not equal to "attribute". * */ public ModelMBeanAttributeInfo(String name, String type, String description, boolean isReadable, boolean isWritable, boolean isIs, Descriptor descriptor) { super(name, type, description, isReadable, isWritable, isIs); if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, "ModelMBeanAttributeInfo(String,String,String," + "boolean,boolean,boolean,Descriptor)" + "Entry " + name); } attrDescriptor = validDescriptor(descriptor); } /** * Constructs a new ModelMBeanAttributeInfo object from this * ModelMBeanAttributeInfo Object. A default descriptor will * be created. * * @param inInfo the ModelMBeanAttributeInfo to be duplicated */ public ModelMBeanAttributeInfo(ModelMBeanAttributeInfo inInfo) { super(inInfo.getName(), inInfo.getType(), inInfo.getDescription(), inInfo.isReadable(), inInfo.isWritable(), inInfo.isIs()); if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, "ModelMBeanAttributeInfo(ModelMBeanAttributeInfo) " + "Entry"); } Descriptor newDesc = inInfo.getDescriptor(); attrDescriptor = validDescriptor(newDesc); } /** * Gets a copy of the associated Descriptor for the * ModelMBeanAttributeInfo. * * @return Descriptor associated with the * ModelMBeanAttributeInfo object. * * @see #setDescriptor */ public Descriptor getDescriptor() { if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, "Entry"); } if (attrDescriptor == null) { attrDescriptor = validDescriptor(null); } return ((Descriptor) attrDescriptor.clone()); } /** * Sets associated Descriptor (full replace) for the * ModelMBeanAttributeDescriptor. If the new Descriptor is * null, then the associated Descriptor reverts to a default * descriptor. The Descriptor is validated before it is * assigned. If the new Descriptor is invalid, then a * RuntimeOperationsException wrapping an * IllegalArgumentException is thrown. * @param inDescriptor replaces the Descriptor associated with the * ModelMBeanAttributeInfo * * @exception RuntimeOperationsException Wraps an * IllegalArgumentException for an invalid Descriptor * * @see #getDescriptor */ public void setDescriptor(Descriptor inDescriptor) { attrDescriptor = validDescriptor(inDescriptor); } /** * Creates and returns a new ModelMBeanAttributeInfo which is a duplicate of this ModelMBeanAttributeInfo. * * @exception RuntimeOperationsException for illegal value for * field Names or field Values. If the descriptor construction * fails for any reason, this exception will be thrown. */ @Override public Object clone() { if (MODELMBEAN_LOGGER.isLoggable(Level.TRACE)) { MODELMBEAN_LOGGER.log(Level.TRACE, "Entry"); } return (new ModelMBeanAttributeInfo(this)); } /** * Returns a human-readable version of the * ModelMBeanAttributeInfo instance. */ @Override public String toString() { return "ModelMBeanAttributeInfo: " + this.getName() + " ; Description: " + this.getDescription() + " ; Types: " + this.getType() + " ; isReadable: " + this.isReadable() + " ; isWritable: " + this.isWritable() + " ; Descriptor: " + this.getDescriptor(); } /** * Clones the passed in Descriptor, sets default values, and checks for validity. * If the Descriptor is invalid (for instance by having the wrong "name"), * this indicates programming error and a RuntimeOperationsException will be thrown. * * The following fields will be defaulted if they are not already set: * displayName=this.getName(),name=this.getName(),descriptorType = "attribute" * * @param in Descriptor to be checked, or null which is equivalent to * an empty Descriptor. * @exception RuntimeOperationsException if Descriptor is invalid */ private Descriptor validDescriptor(final Descriptor in) throws RuntimeOperationsException { Descriptor clone; boolean defaulted = (in == null); if (defaulted) { clone = new DescriptorSupport(); MODELMBEAN_LOGGER.log(Level.TRACE, "Null Descriptor, creating new."); } else { clone = (Descriptor) in.clone(); } //Setting defaults. if (defaulted && clone.getFieldValue("name") == null) { clone.setField("name", this.getName()); MODELMBEAN_LOGGER.log(Level.TRACE, "Defaulting Descriptor name to " + this.getName()); } if (defaulted && clone.getFieldValue("descriptorType") == null) { clone.setField("descriptorType", "attribute"); MODELMBEAN_LOGGER.log(Level.TRACE, "Defaulting descriptorType to \"attribute\""); } if (clone.getFieldValue("displayName") == null) { clone.setField("displayName", this.getName()); MODELMBEAN_LOGGER.log(Level.TRACE, "Defaulting Descriptor displayName to " + this.getName()); } //Checking validity if (!clone.isValid()) { throw new RuntimeOperationsException(new IllegalArgumentException("Invalid Descriptor argument"), "The isValid() method of the Descriptor object itself returned false," + "one or more required fields are invalid. Descriptor:" + clone.toString()); } if (!getName().equalsIgnoreCase((String) clone.getFieldValue("name"))) { throw new RuntimeOperationsException(new IllegalArgumentException("Invalid Descriptor argument"), "The Descriptor \"name\" field does not match the object described. " + " Expected: " + this.getName() + " , was: " + clone.getFieldValue("name")); } if (!"attribute".equalsIgnoreCase((String) clone.getFieldValue("descriptorType"))) { throw new RuntimeOperationsException(new IllegalArgumentException("Invalid Descriptor argument"), "The Descriptor \"descriptorType\" field does not match the object described. " + " Expected: \"attribute\" ," + " was: " + clone.getFieldValue("descriptorType")); } return clone; } /** * Deserializes a {@link ModelMBeanAttributeInfo} from an {@link ObjectInputStream}. */ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { // New serial form ignores extra field "currClass" in.defaultReadObject(); } /** * Serializes a {@link ModelMBeanAttributeInfo} to an {@link ObjectOutputStream}. */ private void writeObject(ObjectOutputStream out) throws IOException { if (compat) { // Serializes this instance in the old serial form // ObjectOutputStream.PutField fields = out.putFields(); fields.put("attrDescriptor", attrDescriptor); fields.put("currClass", currClass); out.writeFields(); } else { // Serializes this instance in the new serial form // out.defaultWriteObject(); } } }