| /* MonitorInfo.java - Information on a monitor lock. |
| Copyright (C) 2006 Free Software Foundation |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.lang.management; |
| |
| import javax.management.openmbean.CompositeData; |
| import javax.management.openmbean.CompositeType; |
| import javax.management.openmbean.SimpleType; |
| |
| /** |
| * Provides information on a monitor lock held by a thread. |
| * A monitor lock is obtained when a thread enters a synchronized |
| * block or method. |
| * |
| * @author Andrew John Hughes (gnu_andrew@member.fsf.org) |
| * @since 1.6 |
| */ |
| public class MonitorInfo |
| extends LockInfo |
| { |
| |
| /** |
| * The stack depth at which the lock was obtained. |
| */ |
| private int stackDepth; |
| |
| /** |
| * The stack frame at which the lock was obtained. |
| */ |
| private StackTraceElement stackFrame; |
| |
| /** |
| * Constructs a new {@link MonitorInfo} using the specified |
| * lock class name and identity hash code, and the given |
| * stack depth and frame. |
| * |
| * @param className the class name of the lock object. |
| * @param identityHashCode the identity hash code of the lock object. |
| * @param stackDepth the depth of the stack at which the lock |
| * was obtained. |
| * @param stackFrame the frame of the stack at which the lock was |
| * obtained. |
| * @throws IllegalArgumentException if the stack depth and frame are |
| * inconsistent i.e. the frame is |
| * <code>null</code> but the depth is |
| * ≥ 0, or the frame is not |
| * <code>null</code> but the depth is |
| * < 0. |
| */ |
| public MonitorInfo(String className, int identityHashCode, int stackDepth, |
| StackTraceElement stackFrame) |
| { |
| super(className, identityHashCode); |
| if (stackFrame == null && stackDepth >= 0) |
| throw new IllegalArgumentException("The stack frame is null, but the " + |
| "stack depth is greater than or equal " + |
| "to zero."); |
| if (stackFrame != null && stackDepth < 0) |
| throw new IllegalArgumentException("The stack frame is not null, but the " + |
| "stack depth is less than zero."); |
| this.stackDepth = stackDepth; |
| this.stackFrame = stackFrame; |
| } |
| |
| /** |
| * <p> |
| * Returns a {@link MonitorInfo} instance using the values |
| * given in the supplied |
| * {@link javax.management.openmbean.CompositeData} object. |
| * The composite data instance should contain the following |
| * attributes with the specified types: |
| * </p> |
| * <table> |
| * <th><td>Name</td><td>Type</td></th> |
| * <tr><td>className</td><td>java.lang.String</td></tr> |
| * <tr><td>identityHashCode</td><td>java.lang.Integer</td></tr> |
| * <tr><td>lockedStackDepth</td><td>java.lang.Integer</td></tr> |
| * <tr><td>lockedStackFrame</td><td>javax.management.openmbean.CompositeData |
| * </td></tr> |
| * </table> |
| * <p> |
| * The stack trace is further described as: |
| * </p> |
| * <table> |
| * <th><td>Name</td><td>Type</td></th> |
| * <tr><td>className</td><td>java.lang.String</td></tr> |
| * <tr><td>methodName</td><td>java.lang.String</td></tr> |
| * <tr><td>fileName</td><td>java.lang.String</td></tr> |
| * <tr><td>lineNumber</td><td>java.lang.Integer</td></tr> |
| * <tr><td>nativeMethod</td><td>java.lang.Boolean</td></tr> |
| * </table> |
| * |
| * @param data the composite data structure to take values from. |
| * @return a new instance containing the values from the |
| * composite data structure, or <code>null</code> |
| * if the data structure was also <code>null</code>. |
| * @throws IllegalArgumentException if the composite data structure |
| * does not match the structure |
| * outlined above. |
| */ |
| public static MonitorInfo from(CompositeData data) |
| { |
| if (data == null) |
| return null; |
| CompositeType type = data.getCompositeType(); |
| ThreadInfo.checkAttribute(type, "ClassName", SimpleType.STRING); |
| ThreadInfo.checkAttribute(type, "IdentityHashCode", SimpleType.INTEGER); |
| ThreadInfo.checkAttribute(type, "LockedStackDepth", SimpleType.INTEGER); |
| ThreadInfo.checkAttribute(type, "LockedStackFrame", |
| ThreadInfo.getStackTraceType()); |
| CompositeData frame = (CompositeData) data.get("LockedStackFrame"); |
| return new MonitorInfo((String) data.get("ClassName"), |
| (Integer) data.get("IdentityHashCode"), |
| (Integer) data.get("LockedStackDepth"), |
| new StackTraceElement((String) frame.get("ClassName"), |
| (String) frame.get("MethodName"), |
| (String) frame.get("FileName"), |
| (Integer) frame.get("LineNumber"))); |
| } |
| |
| /** |
| * Returns the depth of the stack at which the lock was obtained. |
| * This works as an index into the array returned by |
| * {@link ThreadInfo#getStackTrace()}. |
| * |
| * @return the depth of the stack at which the lock was obtained, |
| * or a negative number if this information is unavailable. |
| */ |
| public int getLockedStackDepth() |
| { |
| return stackDepth; |
| } |
| |
| /** |
| * Returns the stack frame at which the lock was obtained. |
| * |
| * @return the stack frame at which the lock was obtained, |
| * or <code>null</code> if this informati0on is unavailable. |
| */ |
| public StackTraceElement getLockedStackFrame() |
| { |
| return stackFrame; |
| } |
| |
| } |