io.camunda.zeebe.spring.client.bean.MethodInfo Maven / Gradle / Ivy
/*
* Copyright © 2017 camunda services GmbH ([email protected])
*
* 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 io.camunda.zeebe.spring.client.bean;
import static org.springframework.core.annotation.AnnotationUtils.findAnnotation;
import java.lang.annotation.Annotation;
import java.lang.invoke.MethodHandles;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Parameter;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.StandardReflectionParameterNameDiscoverer;
public class MethodInfo implements BeanInfo {
private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
private static final StandardReflectionParameterNameDiscoverer PARAMETER_NAME_DISCOVERER =
new StandardReflectionParameterNameDiscoverer();
protected ClassInfo classInfo;
protected Method method;
protected MethodInfo(final ClassInfo classInfo, final Method method) {
this.classInfo = classInfo;
this.method = method;
}
protected MethodInfo(final MethodInfo original) {
classInfo = original.classInfo;
method = original.method;
}
@Override
public Object getBean() {
return classInfo.getBean();
}
@Override
public String getBeanName() {
return classInfo.getBeanName();
}
@Override
public String toString() {
return "MethodInfo{" + "classInfo=" + classInfo + ", method=" + method + '}';
}
public String getMethodName() {
return method.getName();
}
public Object invoke(final Object... args) throws Exception {
try {
return method.invoke(getBean(), args);
} catch (final InvocationTargetException e) {
final Throwable targetException = e.getTargetException();
if (targetException instanceof Exception) {
throw (Exception) targetException;
} else {
throw new RuntimeException("Failed to invoke method: " + method.getName(), targetException);
}
} catch (final IllegalAccessException e) {
throw new RuntimeException("Failed to invoke method: " + method.getName(), e);
}
}
public Optional getAnnotation(final Class type) {
return Optional.ofNullable(findAnnotation(method, type));
}
public List getParameters() {
final Parameter[] parameters = method.getParameters();
final String[] parameterNames = getParameterNames();
final ArrayList result = new ArrayList<>();
for (int i = 0; i < parameters.length; i++) {
result.add(new ParameterInfo(parameters[i], parameterNames[i]));
}
return result;
}
private String[] getParameterNames() {
String[] parameterNames = PARAMETER_NAME_DISCOVERER.getParameterNames(method);
if (parameterNames == null) {
LOG.warn(
"Parameter names of method "
+ method.getName()
+ " could not be discoverd. Please set compiler flag -parameters if you rely on parameter names (e.g. for variable names to fetch from Zeebe)");
// use default names to avoid null pointer exceptions
final Parameter[] parameters = method.getParameters();
parameterNames = new String[parameters.length];
for (int i = 0; i < parameters.length; i++) {
parameterNames[i] = "arg" + i;
}
}
return parameterNames;
}
public List getParametersFilteredByAnnotation(final Class type) {
final Parameter[] parameters = method.getParameters();
final String[] parameterNames = getParameterNames();
final ArrayList result = new ArrayList<>();
for (int i = 0; i < parameters.length; i++) {
if (parameters[i].isAnnotationPresent(type)) {
result.add(new ParameterInfo(parameters[i], parameterNames[i]));
}
}
return result;
}
public static MethodInfoBuilder builder() {
return new MethodInfoBuilder();
}
public static final class MethodInfoBuilder {
private ClassInfo classInfo;
private Method method;
private MethodInfoBuilder() {}
public MethodInfoBuilder classInfo(final ClassInfo classInfo) {
this.classInfo = classInfo;
return this;
}
public MethodInfoBuilder method(final Method method) {
this.method = method;
return this;
}
public MethodInfo build() {
return new MethodInfo(classInfo, method);
}
}
}