com.cedarsoftware.util.ExceptionUtilities Maven / Gradle / Ivy
package com.cedarsoftware.util;
import java.util.concurrent.Callable;
/**
* Useful Exception Utilities. This class also provides the
* {@code uncheckedThrow(Throwable)} helper which allows rethrowing any
* {@link Throwable} without declaring it.
*
* @author Ken Partlow ([email protected])
*
* Copyright (c) Cedar Software LLC
*
* Licensed 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
*
* License
*
* 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.
*/
public final class ExceptionUtilities {
private ExceptionUtilities() {
super();
}
/**
* @return Throwable representing the actual cause (most nested exception).
*/
public static Throwable getDeepestException(Throwable e) {
while (e.getCause() != null) {
e = e.getCause();
}
return e;
}
/**
* Executes the provided {@link Callable} and returns its result. If the callable throws any {@link Throwable},
* the method returns the specified {@code defaultValue} instead.
*
*
* Warning: This method suppresses all {@link Throwable} instances, including {@link Error}s
* and {@link RuntimeException}s. Use this method with caution, as it can make debugging difficult
* by hiding critical errors.
*
*
*
* Usage Example:
*
* {@code
* // Example using safelyIgnoreException with a Callable that may throw an exception
* String result = safelyIgnoreException(() -> potentiallyFailingOperation(), "defaultValue");
* System.out.println(result); // Outputs the result of the operation or "defaultValue" if an exception was thrown
* }
*
*
* When to Use: Use this method in scenarios where you want to execute a task that might throw
* an exception, but you prefer to provide a fallback value instead of handling the exception explicitly.
* This can simplify code in cases where exception handling is either unnecessary or handled elsewhere.
*
*
*
* Caution: Suppressing all exceptions can obscure underlying issues, making it harder to identify and
* fix problems. It is generally recommended to handle specific exceptions that you expect and can recover from,
* rather than catching all {@link Throwable} instances.
*
*
* @param the type of the result returned by the callable
* @param callable the {@link Callable} to execute
* @param defaultValue the default value to return if the callable throws an exception
* @return the result of {@code callable.call()} if no exception is thrown, otherwise {@code defaultValue}
*
* @throws IllegalArgumentException if {@code callable} is {@code null}
*
* @see Callable
*/
public static T safelyIgnoreException(Callable callable, T defaultValue) {
try {
return callable.call();
} catch (Throwable e) {
return defaultValue;
}
}
/**
* Executes the provided {@link Runnable} and safely ignores any exceptions thrown during its execution.
*
*
* Warning: This method suppresses all {@link Throwable} instances, including {@link Error}s
* and {@link RuntimeException}s. Use this method with caution, as it can make debugging difficult
* by hiding critical errors.
*
*
* @param runnable the {@code Runnable} to execute
*/
public static void safelyIgnoreException(Runnable runnable) {
try {
runnable.run();
} catch (Throwable ignored) {
}
}
/**
* Safely Ignore a Throwable or rethrow if it is a Throwable that should
* not be ignored.
*
* @param t Throwable to possibly ignore (ThreadDeath and OutOfMemory are not ignored).
*/
public static void safelyIgnoreException(Throwable t) {
if (t instanceof OutOfMemoryError) {
throw (OutOfMemoryError) t;
}
}
/**
* Throws any {@link Throwable} without declaring it. Useful when converting Groovy code to Java or otherwise
* bypassing checked exceptions. No longer do you need to declare checked exceptions, which are not always best
* handled by the immediate calling class. This will still an IOException, for example, without you declaring as
* a throws clause forcing the caller to deal with it, where as a higher level more suitable place that catches
* Exception will still catch it as an IOException (in this case). Helps the shift away from Checked exceptions,
* which imho, was not a good choice for the Java language.
*
* @param t throwable to be rethrown unchecked
* @param type parameter used to trick the compiler
* @throws T never actually thrown, but declared for compiler satisfaction
*/
@SuppressWarnings("unchecked")
public static void uncheckedThrow(Throwable t) throws T {
throw (T) t; // the cast fools the compiler into thinking this is unchecked
}
}