jdk/src/share/classes/javax/management/openmbean/MXBeanMapping.java
changeset 4159 9e3aae7675f1
parent 4158 0b4d21bc8b5c
parent 4156 acaa49a2768a
child 4160 bda0a85afcb7
--- a/jdk/src/share/classes/javax/management/openmbean/MXBeanMapping.java	Wed Oct 21 15:47:09 2009 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,210 +0,0 @@
-/*
- * Copyright 2007-2008 Sun Microsystems, Inc.  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.  Sun designates this
- * particular file as subject to the "Classpath" exception as provided
- * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
- */
-
-package javax.management.openmbean;
-
-import java.io.InvalidObjectException;
-import java.lang.reflect.Type;
-
-/**
- * <p>A custom mapping between Java types and Open types for use in MXBeans.
- * To define such a mapping, subclass this class and define at least the
- * {@link #fromOpenValue fromOpenValue} and {@link #toOpenValue toOpenValue}
- * methods, and optionally the {@link #checkReconstructible} method.
- * Then either use an {@link MXBeanMappingClass} annotation on your custom
- * Java types, or include this MXBeanMapping in an
- * {@link MXBeanMappingFactory}.</p>
- *
- * <p>For example, suppose we have a class {@code MyLinkedList}, which looks
- * like this:</p>
- *
- * <pre>
- * public class MyLinkedList {
- *     public MyLinkedList(String name, MyLinkedList next) {...}
- *     public String getName() {...}
- *     public MyLinkedList getNext() {...}
- * }
- * </pre>
- *
- * <p>This is not a valid type for MXBeans, because it contains a
- * self-referential property "next" defined by the {@code getNext()}
- * method.  MXBeans do not support recursive types.  So we would like
- * to specify a mapping for {@code MyLinkedList} explicitly. When an
- * MXBean interface contains {@code MyLinkedList}, that will be mapped
- * into a {@code String[]}, which is a valid Open Type.</p>
- *
- * <p>To define this mapping, we first subclass {@code MXBeanMapping}:</p>
- *
- * <pre>
- * public class MyLinkedListMapping extends MXBeanMapping {
- *     public MyLinkedListMapping(Type type) throws OpenDataException {
- *         super(MyLinkedList.class, ArrayType.getArrayType(SimpleType.STRING));
- *         if (type != MyLinkedList.class)
- *             throw new OpenDataException("Mapping only valid for MyLinkedList");
- *     }
- *
- *     {@literal @Override}
- *     public Object fromOpenValue(Object openValue) throws InvalidObjectException {
- *         String[] array = (String[]) openValue;
- *         MyLinkedList list = null;
- *         for (int i = array.length - 1; i &gt;= 0; i--)
- *             list = new MyLinkedList(array[i], list);
- *         return list;
- *     }
- *
- *     {@literal @Override}
- *     public Object toOpenValue(Object javaValue) throws OpenDataException {
- *         ArrayList&lt;String&gt; array = new ArrayList&lt;String&gt;();
- *         for (MyLinkedList list = (MyLinkedList) javaValue; list != null;
- *              list = list.getNext())
- *             array.add(list.getName());
- *         return array.toArray(new String[0]);
- *     }
- * }
- * </pre>
- *
- * <p>The call to the superclass constructor specifies what the
- * original Java type is ({@code MyLinkedList.class}) and what Open
- * Type it is mapped to ({@code
- * ArrayType.getArrayType(SimpleType.STRING)}). The {@code
- * fromOpenValue} method says how we go from the Open Type ({@code
- * String[]}) to the Java type ({@code MyLinkedList}), and the {@code
- * toOpenValue} method says how we go from the Java type to the Open
- * Type.</p>
- *
- * <p>With this mapping defined, we can annotate the {@code MyLinkedList}
- * class appropriately:</p>
- *
- * <pre>
- * {@literal @MXBeanMappingClass}(MyLinkedListMapping.class)
- * public class MyLinkedList {...}
- * </pre>
- *
- * <p>Now we can use {@code MyLinkedList} in an MXBean interface and it
- * will work.</p>
- *
- * <p>If we are unable to modify the {@code MyLinkedList} class,
- * we can define an {@link MXBeanMappingFactory}.  See the documentation
- * of that class for further details.</p>
- *
- * @see <a href="../MXBean.html#custom">MXBean specification, section
- * "Custom MXBean type mappings"</a>
- */
-public abstract class MXBeanMapping {
-    private final Type javaType;
-    private final OpenType<?> openType;
-    private final Class<?> openClass;
-
-    /**
-     * <p>Construct a mapping between the given Java type and the given
-     * Open Type.</p>
-     *
-     * @param javaType the Java type (for example, {@code MyLinkedList}).
-     * @param openType the Open Type (for example, {@code
-     * ArrayType.getArrayType(SimpleType.STRING)})
-     *
-     * @throws NullPointerException if either argument is null.
-     */
-    protected MXBeanMapping(Type javaType, OpenType<?> openType) {
-        if (javaType == null || openType == null)
-            throw new NullPointerException("Null argument");
-        this.javaType = javaType;
-        this.openType = openType;
-        this.openClass = makeOpenClass(javaType, openType);
-    }
-
-    /**
-     * <p>The Java type that was supplied to the constructor.</p>
-     * @return the Java type that was supplied to the constructor.
-     */
-    public final Type getJavaType() {
-        return javaType;
-    }
-
-    /**
-     * <p>The Open Type that was supplied to the constructor.</p>
-     * @return the Open Type that was supplied to the constructor.
-     */
-    public final OpenType<?> getOpenType() {
-        return openType;
-    }
-
-    /**
-     * <p>The Java class that corresponds to instances of the
-     * {@linkplain #getOpenType() Open Type} for this mapping.</p>
-     * @return the Java class that corresponds to instances of the
-     * Open Type for this mapping.
-     * @see OpenType#getClassName
-     */
-    public final Class<?> getOpenClass() {
-        return openClass;
-    }
-
-    private static Class<?> makeOpenClass(Type javaType, OpenType<?> openType) {
-        if (javaType instanceof Class<?> && ((Class<?>) javaType).isPrimitive())
-            return (Class<?>) javaType;
-        try {
-            String className = OpenType.validClassName(openType.getClassName());
-            return Class.forName(className, false, null);
-        } catch (ClassNotFoundException e) {
-            throw new RuntimeException(e);  // should not happen
-        } catch (OpenDataException e) {
-            throw new IllegalArgumentException("Bad OpenType: " + openType, e);
-        }
-    }
-
-    /**
-     * <p>Convert an instance of the Open Type into the Java type.
-     * @param openValue the value to be converted.
-     * @return the converted value.
-     * @throws InvalidObjectException if the value cannot be converted.
-     */
-    public abstract Object fromOpenValue(Object openValue)
-    throws InvalidObjectException;
-
-    /**
-     * <p>Convert an instance of the Java type into the Open Type.
-     * @param javaValue the value to be converted.
-     * @return the converted value.
-     * @throws OpenDataException if the value cannot be converted.
-     */
-    public abstract Object toOpenValue(Object javaValue)
-    throws OpenDataException;
-
-
-    /**
-     * <p>Throw an appropriate InvalidObjectException if we will not
-     * be able to convert back from the open data to the original Java
-     * object.  The {@link #fromOpenValue fromOpenValue} throws an
-     * exception if a given open data value cannot be converted.  This
-     * method throws an exception if <em>no</em> open data values can
-     * be converted.  The default implementation of this method never
-     * throws an exception.  Subclasses can override it as
-     * appropriate.</p>
-     * @throws InvalidObjectException if {@code fromOpenValue} will throw
-     * an exception no matter what its argument is.
-     */
-    public void checkReconstructible() throws InvalidObjectException {}
-}