--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/javax/management/AttributeValueExp.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,148 @@
+/*
+ * Copyright 1999-2004 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;
+
+
+// RI import
+import javax.management.MBeanServer;
+
+/**
+ * Represents attributes used as arguments to relational constraints.
+ * An <CODE>AttributeValueExp</CODE> may be used anywhere a <CODE>ValueExp</CODE> is required.
+ *
+ * @since 1.5
+ */
+public class AttributeValueExp implements ValueExp  {
+
+
+    /* Serial version */
+    private static final long serialVersionUID = -7768025046539163385L;
+
+    /**
+     * @serial The name of the attribute
+     */
+    private String attr;
+
+    /**
+     * An <code>AttributeValueExp</code> with a null attribute.
+     * @deprecated An instance created with this constructor cannot be
+     * used in a query.
+     */
+    @Deprecated
+    public AttributeValueExp() {
+    }
+
+    /**
+     * Creates a new <CODE>AttributeValueExp</CODE> representing the
+     * specified object attribute, named attr.
+     *
+     * @param attr the name of the attribute whose value is the value
+     * of this {@link ValueExp}.
+     */
+    public AttributeValueExp(String attr) {
+        this.attr = attr;
+    }
+
+    /**
+     * Returns a string representation of the name of the attribute.
+     *
+     * @return the attribute name.
+     */
+    public String getAttributeName()  {
+        return attr;
+    }
+
+    /**
+     * Applies the <CODE>AttributeValueExp</CODE> on an MBean.
+     *
+     * @param name The name of the MBean on which the <CODE>AttributeValueExp</CODE> will be applied.
+     *
+     * @return  The <CODE>ValueExp</CODE>.
+     *
+     * @exception BadAttributeValueExpException
+     * @exception InvalidApplicationException
+     * @exception BadStringOperationException
+     * @exception BadBinaryOpValueExpException
+     *
+     */
+    public ValueExp apply(ObjectName name) throws BadStringOperationException, BadBinaryOpValueExpException,
+        BadAttributeValueExpException, InvalidApplicationException {
+        Object result = getAttribute(name);
+
+        if (result instanceof Number) {
+            return new NumericValueExp((Number)result);
+        } else if (result instanceof String) {
+            return new StringValueExp((String)result);
+        } else if (result instanceof Boolean) {
+            return new BooleanValueExp((Boolean)result);
+        } else {
+            throw new BadAttributeValueExpException(result);
+        }
+    }
+
+    /**
+     * Returns the string representing its value.
+     */
+    public String toString()  {
+        return attr;
+    }
+
+
+    /**
+     * Sets the MBean server on which the query is to be performed.
+     *
+     * @param s The MBean server on which the query is to be performed.
+     */
+    /* There is no need for this method, because if a query is being
+       evaluted an AttributeValueExp can only appear inside a QueryExp,
+       and that QueryExp will itself have done setMBeanServer.  */
+    public void setMBeanServer(MBeanServer s)  {
+    }
+
+
+    /**
+     * Return the value of the given attribute in the named MBean.
+     * If the attempt to access the attribute generates an exception,
+     * return null.
+     *
+     * @param name the name of the MBean whose attribute is to be returned.
+     *
+     * @return the value of the attribute, or null if it could not be
+     * obtained.
+     */
+    protected Object getAttribute(ObjectName name) {
+        try {
+            // Get the value from the MBeanServer
+
+            MBeanServer server = QueryEval.getMBeanServer();
+
+            return server.getAttribute(name, attr);
+        } catch (Exception re) {
+            return null;
+        }
+    }
+
+}