/**
* Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite
* contributors
*
* This file is part of EvoSuite.
*
* EvoSuite is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 3.0 of the License, or
* (at your option) any later version.
*
* EvoSuite 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
* Lesser Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* <p>DebuggingObjectOutputStream class.</p>
*
* @author Gordon Fraser
*/
package org.evosuite.utils;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
public class DebuggingObjectOutputStream extends ObjectOutputStream {
private static final Field DEPTH_FIELD;
static {
try {
DEPTH_FIELD = ObjectOutputStream.class.getDeclaredField("depth");
DEPTH_FIELD.setAccessible(true);
} catch (NoSuchFieldException e) {
throw new AssertionError(e);
}
}
final List<Object> stack = new ArrayList<Object>();
/**
* Indicates whether or not OOS has tried to write an IOException
* (presumably as the result of a serialization error) to the stream.
*/
boolean broken = false;
/**
* <p>Constructor for DebuggingObjectOutputStream.</p>
*
* @param out a {@link java.io.OutputStream} object.
* @throws java.io.IOException if any.
*/
public DebuggingObjectOutputStream(OutputStream out) throws IOException {
super(out);
enableReplaceObject(true);
}
/**
* {@inheritDoc}
*
* Abuse {@code replaceObject()} as a hook to maintain our stack.
*/
@Override
protected Object replaceObject(Object o) {
// ObjectOutputStream writes serialization
// exceptions to the stream. Ignore
// everything after that so we don't lose
// the path to a non-serializable object. So
// long as the user doesn't write an
// IOException as the root object, we're OK.
int currentDepth = currentDepth();
if (o instanceof IOException && currentDepth == 0) {
broken = true;
}
if (!broken) {
truncate(currentDepth);
//System.out.println("Current object: " + o.getClass().getName());
stack.add(o);
}
return o;
}
private void truncate(int depth) {
while (stack.size() > depth) {
pop();
}
}
private Object pop() {
return stack.remove(stack.size() - 1);
}
/**
* Returns a 0-based depth within the object graph of the current object
* being serialized.
*/
private int currentDepth() {
try {
Integer oneBased = ((Integer) DEPTH_FIELD.get(this));
return oneBased - 1;
} catch (IllegalAccessException e) {
throw new AssertionError(e);
}
}
/**
* Returns the path to the last object serialized. If an exception occurred,
* this should be the path to the non-serializable object.
*
* @return a {@link java.util.List} object.
*/
public List<Object> getStack() {
return stack;
}
}