/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE
* or https://OpenDS.dev.java.net/OpenDS.LICENSE.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
* add the following below this CDDL HEADER, with the fields enclosed
* by brackets "[]" replaced with your own identifying information:
* Portions Copyright [yyyy] [name of copyright owner]
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*
*
* Copyright 2006-2008 Sun Microsystems, Inc.
*/
package org.opends.server.plugins.profiler;
import java.util.Arrays;
import java.util.HashMap;
import static org.opends.server.loggers.debug.DebugLogger.*;
import org.opends.server.loggers.debug.DebugTracer;
import org.opends.server.types.DebugLogLevel;
/**
* This class defines a data structure for holding information about a stack
* frame captured by the Directory Server profiler. It will contain the class
* and method name for this frame, the set of line numbers within that method
* that were captured along with the number of times they were seen, as well as
* references to subordinate frames that were encountered.
*/
public class ProfileStackFrame
implements Comparable
{
/**
* The tracer object for the debug logger.
*/
private static final DebugTracer TRACER = getTracer();
// The mapping between the line numbers for this stack frame and the
// number of times that they were encountered.
private HashMap<Integer,Long> lineNumbers;
// The mapping for subordinate frames. It is mapped to itself because we
// use a fuzzy equality comparison and sets do not have a get method that
// can be used to retrieve a specified object.
private HashMap<ProfileStackFrame,ProfileStackFrame> subordinateFrames;
// The class name for this stack frame.
private String className;
// The method name for this stack frame.
private String methodName;
/**
* Creates a new profile stack frame with the provided information.
*
* @param className The class name for use in this stack frame.
* @param methodName The method name for use in this stack frame.
*/
public ProfileStackFrame(String className, String methodName)
{
this.className = className;
this.methodName = methodName;
lineNumbers = new HashMap<Integer,Long>();
subordinateFrames = new HashMap<ProfileStackFrame,ProfileStackFrame>();
}
/**
* Retrieves the class name for this stack frame.
*
* @return The class name for this stack frame.
*/
public String getClassName()
{
return className;
}
/**
* Retrieves the method name for this stack frame.
*
* @return The method name for this stack frame.
*/
public String getMethodName()
{
return methodName;
}
/**
* Retrieves the method name for this stack frame in a manner that will be
* safe for use in an HTML context. Currently, this simply replaces angle
* brackets with the appropriate HTML equivalent.
*
* @return The generated safe name.
*/
public String getHTMLSafeMethodName()
{
int length = methodName.length();
StringBuilder buffer = new StringBuilder(length + 6);
for (int i=0; i < length; i++)
{
char c = methodName.charAt(i);
if (c == '<')
{
buffer.append("<");
}
else if (c == '>')
{
buffer.append(">");
}
else
{
buffer.append(c);
}
}
return buffer.toString();
}
/**
* Retrieves the mapping between the line numbers associated with this method
* and the number of occurrences for each of those line numbers.
*
* @return The mapping between the line numbers associated with this method
* and the number of occurrences for each of those line numbers.
*/
public HashMap<Integer,Long> getLineNumbers()
{
return lineNumbers;
}
/**
* Updates the count for the number of occurrences of a given stack frame
* for the specified line number.
*
* @param lineNumber The line number for which to update the count.
* @param numOccurrences The number of times the specified line was
* encountered for this stack frame.
*/
public void updateLineNumberCount(int lineNumber, long numOccurrences)
{
Long existingCount = lineNumbers.get(lineNumber);
if (existingCount == null)
{
lineNumbers.put(lineNumber, numOccurrences);
}
else
{
lineNumbers.put(lineNumber, existingCount+numOccurrences);
}
}
/**
* Retrieves the total number of times that a frame with this class and
* method name was seen by the profiler thread.
*
* @return The total number of times that a frame with this class and method
* name was seen by the profiler thread.
*/
public long getTotalCount()
{
long totalCount = 0;
for (Long l : lineNumbers.values())
{
totalCount += l;
}
return totalCount;
}
/**
* Retrieves an array containing the subordinate frames that were seen below
* this frame in stack traces. The elements of the array will be sorted in
* descending order of the number of occurrences.
*
* @return An array containing the subordinate frames that were seen below
* this frame in stack traces.
*/
public ProfileStackFrame[] getSubordinateFrames()
{
ProfileStackFrame[] subFrames = new ProfileStackFrame[0];
subFrames = subordinateFrames.values().toArray(subFrames);
Arrays.sort(subFrames);
return subFrames;
}
/**
* Indicates whether this stack frame has one or more subordinate frames.
*
* @return <CODE>true</CODE> if this stack frame has one or more subordinate
* frames, or <CODE>false</CODE> if not.
*/
public boolean hasSubFrames()
{
return (! subordinateFrames.isEmpty());
}
/**
* Recursively processes the frames of the provided stack, adding them as
* nested subordinate frames of this stack frame.
*
* @param stack The stack trace to use to obtain the frames.
* @param depth The slot of the next frame to process in the
* provided array.
* @param count The number of occurrences for the provided stack.
* @param stacksByMethod The set of stack traces mapped from method name to
* their corresponding stack traces.
*/
public void recurseSubFrames(ProfileStack stack, int depth, long count,
HashMap<String,HashMap<ProfileStack,Long>> stacksByMethod)
{
if (depth < 0)
{
return;
}
String cName = stack.getClassName(depth);
String mName = stack.getMethodName(depth);
ProfileStackFrame f = new ProfileStackFrame(cName, mName);
int lineNumber = stack.getLineNumber(depth);
ProfileStackFrame subFrame = subordinateFrames.get(f);
if (subFrame == null)
{
subFrame = f;
subordinateFrames.put(subFrame, subFrame);
}
subFrame.updateLineNumberCount(lineNumber, count);
String classAndMethod = cName + "." + mName;
HashMap<ProfileStack,Long> stackMap = stacksByMethod.get(classAndMethod);
if (stackMap == null)
{
stackMap = new HashMap<ProfileStack,Long>();
stacksByMethod.put(classAndMethod, stackMap);
}
stackMap.put(stack, count);
subFrame.recurseSubFrames(stack, (depth-1), count, stacksByMethod);
}
/**
* Retrieves the hash code for this stack frame. It will be the sum of the
* hash codes for the class and method name.
*
* @return The hash code for this stack frame.
*/
public int hashCode()
{
return (className.hashCode() + methodName.hashCode());
}
/**
* Indicates whether the provided object is equal to this stack frame. It
* will be considered equal if it is a profile stack frame with the same class
* and method name.
*
* @param o The object for which to make the determination.
*
* @return <CODE>true</CODE> if the provided object may be considered equal
* to this stack frame, or <CODE>false</CODE> if not.
*/
public boolean equals(Object o)
{
if (o == null)
{
return false;
}
else if (this == o)
{
return true;
}
try
{
ProfileStackFrame f = (ProfileStackFrame) o;
return (className.equals(f.className) && methodName.equals(f.methodName));
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
return false;
}
}
/**
* Indicates the order of this profile stack frame relative to the provided
* object in a sorted list. The order will be primarily based on number of
* occurrences, with an equivalent number of occurrences falling back on
* alphabetical by class and method names.
*
* @param o The objectfor which to make the comparison.
*
* @return A negative integer if this stack frame should come before the
* provided object in a sorted list, a positive integer if it should
* come after the provided object, or zero if they should have
* equivalent order.
*
* @throws ClassCastException If the provided object is not a profile stack
* frame.
*/
public int compareTo(Object o)
throws ClassCastException
{
ProfileStackFrame f;
try
{
f = (ProfileStackFrame) o;
}
catch (ClassCastException cce)
{
throw cce;
}
long thisCount = getTotalCount();
long thatCount = f.getTotalCount();
if (thisCount > thatCount)
{
return -1;
}
else if (thisCount < thatCount)
{
return 1;
}
int value = className.compareTo(f.className);
if (value == 0)
{
value = methodName.compareTo(f.methodName);
}
return value;
}
/**
* Retrieves a string representation of this stack frame. It will contain the
* total number of matching frames, the class name, and the method name.
*
* @return A string representation of this stack frame.
*/
public String toString()
{
StringBuilder buffer = new StringBuilder();
buffer.append(getTotalCount());
buffer.append(" ");
buffer.append(className);
buffer.append('.');
buffer.append(methodName);
return buffer.toString();
}
}