org.springframework.core.NestedRuntimeException Maven / Gradle / Ivy
/*
* Copyright 2002-2007 the original author or authors.
*
* 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
*
* 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.springframework.core;
import java.io.PrintStream;
import java.io.PrintWriter;
/**
* Handy class for wrapping runtime Exceptions
with a root cause.
*
* This time-honoured technique is no longer necessary in Java 1.4, which
* finally provides built-in support for exception nesting. Thus exceptions in
* applications written to use Java 1.4 need not extend this class. To ease
* migration, this class mirrors Java 1.4's nested exceptions as closely as possible.
*
*
This class is abstract
to force the programmer to extend
* the class. getMessage
will include nested exception
* information; printStackTrace
and other like methods will
* delegate to the wrapped exception, if any.
*
*
The similarity between this class and the {@link NestedCheckedException}
* class is unavoidable, as Java forces these two classes to have different
* superclasses (ah, the inflexibility of concrete inheritance!).
*
* @author Rod Johnson
* @author Juergen Hoeller
* @see #getMessage
* @see #printStackTrace
* @see NestedCheckedException
*/
public abstract class NestedRuntimeException extends RuntimeException {
/** Use serialVersionUID from Spring 1.2 for interoperability */
private static final long serialVersionUID = 5439915454935047936L;
/** Root cause of this nested exception */
private Throwable cause;
/**
* Construct a NestedRuntimeException
with the specified detail message.
* @param msg the detail message
*/
public NestedRuntimeException(String msg) {
super(msg);
}
/**
* Construct a NestedRuntimeException
with the specified detail message
* and nested exception.
* @param msg the detail message
* @param cause the nested exception
*/
public NestedRuntimeException(String msg, Throwable cause) {
super(msg);
this.cause = cause;
}
/**
* Return the nested cause, or null
if none.
*
Note that this will only check one level of nesting.
* Use {@link #getRootCause()} to retrieve the innermost cause.
*/
public Throwable getCause() {
// Even if you cannot set the cause of this exception other than through
// the constructor, we check for the cause being "this" here, as the cause
// could still be set to "this" via reflection: for example, by a remoting
// deserializer like Hessian's.
return (this.cause == this ? null : this.cause);
}
/**
* Return the detail message, including the message from the nested exception
* if there is one.
*/
public String getMessage() {
return NestedExceptionUtils.buildMessage(super.getMessage(), getCause());
}
/**
* Print the composite message and the embedded stack trace to the specified stream.
* @param ps the print stream
*/
public void printStackTrace(PrintStream ps) {
if (getCause() == null) {
super.printStackTrace(ps);
}
else {
ps.println(this);
ps.print("Caused by: ");
getCause().printStackTrace(ps);
}
}
/**
* Print the composite message and the embedded stack trace to the specified writer.
* @param pw the print writer
*/
public void printStackTrace(PrintWriter pw) {
if (getCause() == null) {
super.printStackTrace(pw);
}
else {
pw.println(this);
pw.print("Caused by: ");
getCause().printStackTrace(pw);
}
}
/**
* Retrieve the innermost cause of this exception, if any.
*
Currently just traverses NestedRuntimeException
causes.
* Will use the JDK 1.4 exception cause mechanism once Spring requires JDK 1.4.
* @return the innermost exception, or null
if none
* @since 2.0
*/
public Throwable getRootCause() {
Throwable cause = getCause();
if (cause instanceof NestedRuntimeException) {
Throwable rootCause = ((NestedRuntimeException) cause).getRootCause();
return (rootCause != null ? rootCause : cause);
}
else {
return cause;
}
}
/**
* Retrieve the most specific cause of this exception, that is,
* either the innermost cause (root cause) or this exception itself.
*
Differs from {@link #getRootCause()} in that it falls back
* to the present exception if there is no root cause.
* @return the most specific cause (never null
)
* @since 2.0.3
*/
public Throwable getMostSpecificCause() {
Throwable rootCause = getRootCause();
return (rootCause != null ? rootCause : this);
}
/**
* Check whether this exception contains an exception of the given type:
* either it is of the given class itself or it contains a nested cause
* of the given type.
*
Currently just traverses NestedRuntimeException
causes.
* Will use the JDK 1.4 exception cause mechanism once Spring requires JDK 1.4.
* @param exType the exception type to look for
* @return whether there is a nested exception of the specified type
*/
public boolean contains(Class exType) {
if (exType == null) {
return false;
}
if (exType.isInstance(this)) {
return true;
}
Throwable cause = getCause();
if (cause instanceof NestedRuntimeException) {
return ((NestedRuntimeException) cause).contains(exType);
}
else {
return (cause != null && exType.isInstance(cause));
}
}
}