org.springframework.http.converter.json.GsonFactoryBean.java Source code

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Here is the source code for org.springframework.http.converter.json.GsonFactoryBean.java

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/*
 * Copyright 2002-2014 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.http.converter.json;

import java.text.SimpleDateFormat;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;

/**
 * A {@link FactoryBean} for creating a Google Gson 2.x {@link Gson} instance.
 *
 * @author Roy Clarkson
 * @author Juergen Hoeller
 * @since 4.1
 */
public class GsonFactoryBean implements FactoryBean<Gson>, InitializingBean {

    private boolean base64EncodeByteArrays = false;

    private boolean serializeNulls = false;

    private boolean prettyPrinting = false;

    private boolean disableHtmlEscaping = false;

    private String dateFormatPattern;

    private Gson gson;

    /**
     * Whether to Base64-encode {@code byte[]} properties when reading and
     * writing JSON.
     * <p>When set to {@code true}, a custom {@link com.google.gson.TypeAdapter} will be
     * registered via {@link GsonBuilder#registerTypeHierarchyAdapter(Class, Object)}
     * which serializes a {@code byte[]} property to and from a Base64-encoded String
     * instead of a JSON array.
     * <p><strong>NOTE:</strong> Use of this option requires the presence of the
     * Apache Commons Codec library on the classpath when running on Java 6 or 7.
     * On Java 8, the standard {@link java.util.Base64} facility is used instead.
     * @see GsonBuilderUtils#gsonBuilderWithBase64EncodedByteArrays()
     */
    public void setBase64EncodeByteArrays(boolean base64EncodeByteArrays) {
        this.base64EncodeByteArrays = base64EncodeByteArrays;
    }

    /**
     * Whether to use the {@link GsonBuilder#serializeNulls()} option when writing
     * JSON. This is a shortcut for setting up a {@code Gson} as follows:
     * <pre class="code">
     * new GsonBuilder().serializeNulls().create();
     * </pre>
     */
    public void setSerializeNulls(boolean serializeNulls) {
        this.serializeNulls = serializeNulls;
    }

    /**
     * Whether to use the {@link GsonBuilder#setPrettyPrinting()} when writing
     * JSON. This is a shortcut for setting up a {@code Gson} as follows:
     * <pre class="code">
     * new GsonBuilder().setPrettyPrinting().create();
     * </pre>
     */
    public void setPrettyPrinting(boolean prettyPrinting) {
        this.prettyPrinting = prettyPrinting;
    }

    /**
     * Whether to use the {@link GsonBuilder#disableHtmlEscaping()} when writing
     * JSON. Set to {@code true} to disable HTML escaping in JSON. This is a
     * shortcut for setting up a {@code Gson} as follows:
     * <pre class="code">
     * new GsonBuilder().disableHtmlEscaping().create();
     * </pre>
     */
    public void setDisableHtmlEscaping(boolean disableHtmlEscaping) {
        this.disableHtmlEscaping = disableHtmlEscaping;
    }

    /**
     * Define the date/time format with a {@link SimpleDateFormat}-style pattern.
     * This is a shortcut for setting up a {@code Gson} as follows:
     * <pre class="code">
     * new GsonBuilder().setDateFormat(dateFormatPattern).create();
     * </pre>
     */
    public void setDateFormatPattern(String dateFormatPattern) {
        this.dateFormatPattern = dateFormatPattern;
    }

    @Override
    public void afterPropertiesSet() {
        GsonBuilder builder = (this.base64EncodeByteArrays
                ? GsonBuilderUtils.gsonBuilderWithBase64EncodedByteArrays()
                : new GsonBuilder());
        if (this.serializeNulls) {
            builder.serializeNulls();
        }
        if (this.prettyPrinting) {
            builder.setPrettyPrinting();
        }
        if (this.disableHtmlEscaping) {
            builder.disableHtmlEscaping();
        }
        if (this.dateFormatPattern != null) {
            builder.setDateFormat(this.dateFormatPattern);
        }
        this.gson = builder.create();
    }

    /**
     * Return the created Gson instance.
     */
    @Override
    public Gson getObject() {
        return this.gson;
    }

    @Override
    public Class<?> getObjectType() {
        return Gson.class;
    }

    @Override
    public boolean isSingleton() {
        return true;
    }

}