org.apache.log4j.DefaultThrowableRenderer Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.log4j;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.io.LineNumberReader;
import java.io.PrintWriter;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.ArrayList;
import org.apache.log4j.spi.ThrowableRenderer;
/**
* Default implementation of {@link ThrowableRenderer} using {@link Throwable#printStackTrace(PrintWriter)}.
*
* @since 1.2.16
*/
public final class DefaultThrowableRenderer implements ThrowableRenderer {
/**
* Render throwable using Throwable.printStackTrace.
*
* @param throwable throwable, may not be null.
* @return string representation.
*/
public static String[] render(final Throwable throwable) {
final StringWriter sw = new StringWriter();
final PrintWriter pw = new PrintWriter(sw);
try {
throwable.printStackTrace(pw);
} catch (final RuntimeException ex) {
// ignore
}
pw.flush();
final LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
final ArrayList lines = new ArrayList<>();
try {
String line = reader.readLine();
while (line != null) {
lines.add(line);
line = reader.readLine();
}
} catch (final IOException ex) {
if (ex instanceof InterruptedIOException) {
Thread.currentThread().interrupt();
}
lines.add(ex.toString());
}
final String[] tempRep = new String[lines.size()];
lines.toArray(tempRep);
return tempRep;
}
/**
* Construct new instance.
*/
public DefaultThrowableRenderer() {
// empty
}
/**
* {@inheritDoc}
*/
@Override
public String[] doRender(final Throwable throwable) {
return render(throwable);
}
}