org.springframework.security.jackson2.SecurityJacksonModules.java Source code

Introduction

Here is the source code for org.springframework.security.jackson2.SecurityJacksonModules.java

Source

/*
 * Copyright 2015-2016 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.security.jackson2;

import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.databind.Module;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.util.ClassUtils;
import org.springframework.util.ObjectUtils;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * This utility class will find all the SecurityModules in classpath.
 *
 * <p>
 * <pre>
 *     ObjectMapper mapper = new ObjectMapper();
 *     mapper.registerModules(SecurityJacksonModules.getModules());
 * </pre>
 * Above code is equivalent to
 * <p>
 * <pre>
 *     ObjectMapper mapper = new ObjectMapper();
 *     mapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);
 *     mapper.registerModule(new CoreJackson2Module());
 *     mapper.registerModule(new CasJackson2Module());
 *     mapper.registerModule(new WebJackson2Module());
 * </pre>
 *
 * @author Jitendra Singh.
 * @since 4.2
 */
public final class SecurityJacksonModules {

    private static final Log logger = LogFactory.getLog(SecurityJacksonModules.class);
    private static final List<String> securityJackson2ModuleClasses = Arrays.asList(
            "org.springframework.security.jackson2.CoreJackson2Module",
            "org.springframework.security.cas.jackson2.CasJackson2Module",
            "org.springframework.security.web.jackson2.WebJackson2Module");

    private SecurityJacksonModules() {
    }

    public static void enableDefaultTyping(ObjectMapper mapper) {
        if (!ObjectUtils.isEmpty(mapper)) {
            TypeResolverBuilder<?> typeBuilder = mapper.getDeserializationConfig().getDefaultTyper(null);
            if (ObjectUtils.isEmpty(typeBuilder)) {
                mapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);
            }
        }
    }

    private static Module loadAndGetInstance(String className) {
        Module instance = null;
        try {
            logger.debug("Loading module " + className);
            Class<? extends Module> securityModule = (Class<? extends Module>) ClassUtils.forName(className,
                    ClassUtils.getDefaultClassLoader());
            if (!ObjectUtils.isEmpty(securityModule)) {
                logger.debug("Loaded module " + className + ", now registering");
                instance = securityModule.newInstance();
            }
        } catch (ClassNotFoundException e) {
            logger.warn("Module class not found : " + e.getMessage());
        } catch (InstantiationException e) {
            logger.error(e.getMessage());
        } catch (IllegalAccessException e) {
            logger.error(e.getMessage());
        }
        return instance;
    }

    /**
     * @return List of available security modules in classpath.
     */
    public static List<Module> getModules() {
        List<Module> modules = new ArrayList<Module>();
        for (String className : securityJackson2ModuleClasses) {
            Module module = loadAndGetInstance(className);
            if (!ObjectUtils.isEmpty(module)) {
                modules.add(module);
            }
        }
        return modules;
    }
}