org.springframework.boot.devtools.restart.MainMethod Maven / Gradle / Ivy
/*
* Copyright 2012-2023 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
*
* https://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.devtools.restart;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import org.springframework.util.Assert;
/**
* The "main" method located from a running thread.
*
* @author Phillip Webb
*/
class MainMethod {
private final Method method;
MainMethod() {
this(Thread.currentThread());
}
MainMethod(Thread thread) {
Assert.notNull(thread, "Thread must not be null");
this.method = getMainMethod(thread);
}
private Method getMainMethod(Thread thread) {
StackTraceElement[] stackTrace = thread.getStackTrace();
for (int i = stackTrace.length - 1; i >= 0; i--) {
StackTraceElement element = stackTrace[i];
if ("main".equals(element.getMethodName())) {
Method method = getMainMethod(element);
if (method != null) {
return method;
}
}
}
throw new IllegalStateException("Unable to find main method");
}
private Method getMainMethod(StackTraceElement element) {
try {
Class elementClass = Class.forName(element.getClassName());
Method method = elementClass.getDeclaredMethod("main", String[].class);
if (Modifier.isStatic(method.getModifiers())) {
return method;
}
}
catch (Exception ex) {
// Ignore
}
return null;
}
/**
* Returns the actual main method.
* @return the main method
*/
Method getMethod() {
return this.method;
}
/**
* Return the name of the declaring class.
* @return the declaring class name
*/
String getDeclaringClassName() {
return this.method.getDeclaringClass().getName();
}
}