org.apache.logging.log4j.core.util.Throwables 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.logging.log4j.core.util;
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.lang.reflect.UndeclaredThrowableException;
import java.util.ArrayList;
import java.util.List;
/**
* Helps with Throwable objects.
*/
public final class Throwables {
private Throwables() {
}
/**
* Has no effect on Java 6 and below.
*
* @param throwable a Throwable
* @param suppressedThrowable a suppressed Throwable
* @see Throwable#addSuppressed(Throwable)
* @deprecated If compiling on Java 7 and above use {@link Throwable#addSuppressed(Throwable)}.
* Marked as deprecated because Java 6 is deprecated. Will be removed in 2.5.
*/
@Deprecated
public static void addSuppressed(final Throwable throwable, final Throwable suppressedThrowable) {
throwable.addSuppressed(suppressedThrowable);
}
/**
* Returns the deepest cause of the given {@code throwable}.
*
* @param throwable the throwable to navigate
* @return the deepest throwable or the given throwable
*/
public static Throwable getRootCause(final Throwable throwable) {
Throwable cause;
Throwable root = throwable;
while ((cause = root.getCause()) != null) {
root = cause;
}
return root;
}
/**
* Has no effect on Java 6 and below.
*
* @param throwable a Throwable
* @return see Java 7's {@link Throwable#getSuppressed()}
* @see Throwable#getSuppressed()
* @deprecated If compiling on Java 7 and above use {@link Throwable#getSuppressed()}. Marked as deprecated because
* Java 6 is deprecated. Will be removed 2.5.
*/
@Deprecated
public static Throwable[] getSuppressed(final Throwable throwable) {
return throwable.getSuppressed();
}
/**
* Returns true if the getSuppressed method is available.
*
* @return True if getSuppressed is available. As of 2.4, always returns true.
* @deprecated Will be removed in 2.5. As of 2.4, always returns true.
*/
@Deprecated
public static boolean isGetSuppressedAvailable() {
return true;
}
/**
* Converts a Throwable stack trace into a List of Strings.
*
* @param throwable the Throwable
* @return a List of Strings
*/
public static List toStringList(final Throwable throwable) {
final StringWriter sw = new StringWriter();
final PrintWriter pw = new PrintWriter(sw);
try {
throwable.printStackTrace(pw);
} catch (final RuntimeException ex) {
// Ignore any exceptions.
}
pw.flush();
final List lines = new ArrayList<>();
final LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
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());
} finally {
Closer.closeSilently(reader);
}
return lines;
}
/**
* Rethrows a {@link Throwable}, wrapping checked exceptions into an {@link UndeclaredThrowableException}.
*
* @param t the Throwable to throw.
* @throws RuntimeException if {@code t} is a RuntimeException
* @throws Error if {@code t} is an Error
* @throws UndeclaredThrowableException if {@code t} is a checked Exception
* @since 2.1
*/
public static void rethrow(final Throwable t) {
if (t instanceof RuntimeException) {
throw (RuntimeException) t;
}
if (t instanceof Error) {
throw (Error) t;
}
throw new UndeclaredThrowableException(t);
}
}