com.sangupta.comparator.JSONComparer.java Source code

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Here is the source code for com.sangupta.comparator.JSONComparer.java

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/**
 *
 * Comparator - Utility comparison classes
 * Copyright (c) 2012, Sandeep Gupta
 * 
 * http://www.sangupta/projects/comparator
 * 
 * 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 com.sangupta.comparator;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonParser.Feature;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * Compare two given JSON strings for equality by parsing and matching the text contained
 * and ignoring attribute ordering, white spaces etc.
 * 
 * @author sangupta
 * @since 0.2.0
 */
public class JSONComparer {

    /**
     * Compare two JSON string representations.
     * 
     * @param json1
     *            the first representation
     * 
     * @param json2
     *            the second representation
     * 
     * @return <code>true</code> if the two JSON representations represent the
     *         same object, <code>false</code> otherwise.
     * 
     * @throws JsonParseException
     *             if something fails
     * 
     * @throws JsonProcessingException
     *             if something fails
     * 
     * @throws IOException
     *             if something fails
     * 
     */
    public static boolean compareJson(String json1, String json2) throws JsonProcessingException, IOException {
        if (json1 == null || json2 == null) {
            return false;
        }

        if (json1 == json2) {
            return true;
        }

        JsonFactory factory = new JsonFactory();
        factory.enable(Feature.ALLOW_COMMENTS);

        ObjectMapper mapper = new ObjectMapper();
        JsonNode node1 = mapper.readTree(json1);
        JsonNode node2 = mapper.readTree(json2);

        return node1.equals(node2);
    }

    /**
     * Compare two JSON string representations.
     * 
     * @param json1
     *            the first representation
     * 
     * @param json2
     *            the second representation
     * 
     * @return <code>True</code> if the two JSON representations represent the
     *         same object, <code>False</code> otherwise, and <code>null</code>
     *         if something fails
     */
    public static Boolean compareJsonQuietly(String json1, String json2) {
        try {
            return compareJson(json1, json2);
        } catch (JsonProcessingException e) {
            // eat up
        } catch (IOException e) {
            // eat up
        }

        return null;
    }

    /**
     * Compare two JSON representations.
     * 
     * @param stream1
     *            the first representation
     * 
     * @param stream2
     *            the second representation
     * 
     * @return <code>true</code> if the two JSON representations represent the
     *         same object, <code>false</code> otherwise.
     * 
     * @throws JsonParseException
     *             if something fails
     * 
     * @throws JsonProcessingException
     *             if something fails
     * 
     * @throws IOException
     *             if something fails
     * 
     */
    public static boolean compareJson(InputStream stream1, InputStream stream2)
            throws JsonProcessingException, IOException {
        if (stream1 == null || stream2 == null) {
            return false;
        }

        if (stream1 == stream2) {
            return true;
        }

        JsonFactory factory = new JsonFactory();
        factory.enable(Feature.ALLOW_COMMENTS);

        ObjectMapper mapper = new ObjectMapper();
        JsonNode node1 = mapper.readTree(stream1);
        JsonNode node2 = mapper.readTree(stream2);

        return node1.equals(node2);
    }

    /**
     * Compare two JSON representations.
     * 
     * @param stream1
     *            the first representation
     * 
     * @param stream2
     *            the second representation
     * 
     * @return <code>True</code> if the two JSON representations represent the
     *         same object, <code>False</code> otherwise, and <code>null</code>
     *         if something fails
     */
    public static Boolean compareJsonQuietly(InputStream stream1, InputStream stream2) {
        try {
            return compareJson(stream1, stream2);
        } catch (JsonProcessingException e) {
            // eat up
        } catch (IOException e) {
            // eat up
        }

        return null;
    }

    /**
     * Compare two JSON representations.
     * 
     * @param reader1
     *            the first representation
     * 
     * @param reader2
     *            the second representation
     * 
     * @return <code>true</code> if the two JSON representations represent the
     *         same object, <code>false</code> otherwise.
     * 
     * @throws JsonParseException
     *             if something fails
     * 
     * @throws JsonProcessingException
     *             if something fails
     * 
     * @throws IOException
     *             if something fails
     * 
     */
    public static boolean compareJson(Reader reader1, Reader reader2) throws JsonProcessingException, IOException {
        if (reader1 == null || reader2 == null) {
            return false;
        }

        if (reader1 == reader2) {
            return true;
        }

        JsonFactory factory = new JsonFactory();
        factory.enable(Feature.ALLOW_COMMENTS);

        ObjectMapper mapper = new ObjectMapper();
        JsonNode node1 = mapper.readTree(reader1);
        JsonNode node2 = mapper.readTree(reader2);

        return node1.equals(node2);
    }

    /**
     * Compare two JSON representations.
     * 
     * @param reader1
     *            the first representation
     * 
     * @param reader2
     *            the second representation
     * 
     * @return <code>True</code> if the two JSON representations represent the
     *         same object, <code>False</code> otherwise, and <code>null</code>
     *         if something fails
     */
    public static Boolean compareJsonQuietly(Reader reader1, Reader reader2) {
        try {
            return compareJson(reader1, reader2);
        } catch (JsonProcessingException e) {
            // eat up
        } catch (IOException e) {
            // eat up
        }

        return null;
    }

}