/*
* Copyright 2012-2017 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.cli.app;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
/**
* A launcher for {@code SpringApplication} or a {@code SpringApplication} subclass. The
* class that is used can be configured using the System property
* {@code spring.application.class.name} or the {@code SPRING_APPLICATION_CLASS_NAME}
* environment variable. Uses reflection to allow the launching code to exist in a
* separate ClassLoader from the application code.
*
* @author Andy Wilkinson
* @since 1.2.0
* @see System#getProperty(String)
* @see System#getenv(String)
*/
public class SpringApplicationLauncher {
private static final String DEFAULT_SPRING_APPLICATION_CLASS = "org.springframework.boot.SpringApplication";
private final ClassLoader classLoader;
/**
* Creates a new launcher that will use the given {@code classLoader} to load the
* configured {@code SpringApplication} class.
* @param classLoader the {@code ClassLoader} to use
*/
public SpringApplicationLauncher(ClassLoader classLoader) {
this.classLoader = classLoader;
}
/**
* Launches the application created using the given {@code sources}. The application
* is launched with the given {@code args}.
* @param sources The sources for the application
* @param args The args for the application
* @return The application's {@code ApplicationContext}
* @throws Exception if the launch fails
*/
public Object launch(Object[] sources, String[] args) throws Exception {
Map<String, Object> defaultProperties = new HashMap<>();
defaultProperties.put("spring.groovy.template.check-template-location", "false");
Class<?> applicationClass = this.classLoader
.loadClass(getSpringApplicationClassName());
Constructor<?> constructor = applicationClass.getConstructor(Object[].class);
Object application = constructor.newInstance((Object) sources);
applicationClass.getMethod("setDefaultProperties", Map.class).invoke(application,
defaultProperties);
Method method = applicationClass.getMethod("run", String[].class);
return method.invoke(application, (Object) args);
}
private String getSpringApplicationClassName() {
String className = System.getProperty("spring.application.class.name");
if (className == null) {
className = getEnvironmentVariable("SPRING_APPLICATION_CLASS_NAME");
}
if (className == null) {
className = DEFAULT_SPRING_APPLICATION_CLASS;
}
return className;
}
protected String getEnvironmentVariable(String name) {
return System.getenv(name);
}
}