org.springframework.kafka.support.serializer.SerializationUtils Maven / Gradle / Ivy
/*
* Copyright 2020 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.kafka.support.serializer;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.function.BiFunction;
import org.apache.kafka.common.header.Headers;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
/**
* Utilities for serialization.
*
* @author Gary Russell
* @since 2.5
*
*/
public final class SerializationUtils {
private SerializationUtils() {
}
/**
* Convert a property value (FQCN.methodName) to a {@link BiFunction} that takes a
* payload and headers and returns some value. The method must have parameters
* {@code (P, Headers)} or {@code (P)} and be declared as static.
* @param The {@link BiFunction} first parameter type.
* @param The {@link BiFunction} return type.
* @param methodProperty the method name property.
* @param payloadType the {@link BiFunction} first parameter type.
* @param classLoader the class loader.
* @return the function.
*/
@SuppressWarnings("unchecked")
public static BiFunction propertyToMethodInvokingFunction(String methodProperty,
Class payloadType, ClassLoader classLoader) {
int lastDotPosn = methodProperty.lastIndexOf('.');
Assert.state(lastDotPosn > 1,
"the method property needs to be a class name followed by the method name, separated by '.'");
BiFunction function;
Class clazz;
try {
clazz = ClassUtils.forName(methodProperty.substring(0, lastDotPosn), classLoader);
}
catch (ClassNotFoundException | LinkageError e) {
throw new IllegalStateException(e);
}
String methodName = methodProperty.substring(lastDotPosn + 1);
Method method;
try {
method = clazz.getDeclaredMethod(methodName, payloadType, Headers.class);
}
catch (@SuppressWarnings("unused") NoSuchMethodException e) {
try {
method = clazz.getDeclaredMethod(methodName, payloadType);
}
catch (@SuppressWarnings("unused") NoSuchMethodException e1) {
throw new IllegalStateException("the parser method must take '(String, Headers)' or '(String)'");
}
catch (SecurityException e1) {
throw new IllegalStateException(e1);
}
}
catch (SecurityException e) {
throw new IllegalStateException(e);
}
Method parseMethod = method;
if (method.getParameters().length > 1) {
function = (str, headers) -> {
try {
return (T) parseMethod.invoke(null, str, headers);
}
catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
throw new IllegalStateException(e);
}
};
}
else {
function = (str, headers) -> {
try {
return (T) parseMethod.invoke(null, str);
}
catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
throw new IllegalStateException(e);
}
};
}
return function;
}
}