org.springframework.boot.diagnostics.AbstractFailureAnalyzer Maven / Gradle / Ivy
/*
* Copyright 2012-2016 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.boot.diagnostics;
import org.springframework.core.ResolvableType;
/**
* Abstract base class for most {@code FailureAnalyzer} implementations.
*
* @param the type of exception to analyze
* @author Andy Wilkinson
* @author Phillip Webb
* @since 1.4.0
*/
public abstract class AbstractFailureAnalyzer
implements FailureAnalyzer {
@Override
public FailureAnalysis analyze(Throwable failure) {
T cause = findCause(failure, getCauseType());
if (cause != null) {
return analyze(failure, cause);
}
return null;
}
/**
* Returns an analysis of the given {@code failure}, or {@code null} if no analysis
* was possible.
* @param rootFailure the root failure passed to the analyzer
* @param cause the actual found cause
* @return the analysis or {@code null}
*/
protected abstract FailureAnalysis analyze(Throwable rootFailure, T cause);
/**
* Return the cause type being handled by the analyzer. By default the class generic
* is used.
* @return the cause type
*/
@SuppressWarnings("unchecked")
protected Class extends T> getCauseType() {
return (Class extends T>) ResolvableType
.forClass(AbstractFailureAnalyzer.class, getClass()).resolveGeneric();
}
@SuppressWarnings("unchecked")
protected final T findCause(Throwable failure, Class type) {
while (failure != null) {
if (type.isInstance(failure)) {
return (T) failure;
}
failure = failure.getCause();
}
return null;
}
}