org.camunda.bpm.elasticsearch.util.JsonHelper.java Source code

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Here is the source code for org.camunda.bpm.elasticsearch.util.JsonHelper.java

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/*
 * Copyright 2013 - Christian Lipphardt and camunda services GmbH
 *
 * 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.camunda.bpm.elasticsearch.util;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.type.MapType;
import com.fasterxml.jackson.databind.type.TypeFactory;

import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class JsonHelper {

    private static ObjectMapper objectMapper = new ObjectMapper();

    public static <T> T readJsonFromClasspath(Class<T> clazz, String fileName) {
        InputStream inputStream = null;

        try {
            inputStream = IoUtil.getResourceAsStream(fileName);
            if (inputStream == null) {
                throw new RuntimeException("File '" + fileName + "' not found!");
            }

            T typedJson = objectMapper.readValue(inputStream, clazz);

            return typedJson;
        } catch (IOException e) {
            throw new RuntimeException("Unable to load json [" + fileName + "] from classpath", e);
        } finally {
            IoUtil.closeSilently(inputStream);
        }
    }

    public static Map<String, Object> readJsonFromClasspathAsMap(String fileName) {
        InputStream inputStream = null;

        try {
            inputStream = IoUtil.getResourceAsStream(fileName);
            if (inputStream == null) {
                throw new RuntimeException("File '" + fileName + "' not found!");
            }

            MapType type = TypeFactory.defaultInstance().constructMapType(HashMap.class, String.class,
                    Object.class);
            HashMap<String, Object> mapping = objectMapper.readValue(inputStream, type);

            return mapping;
        } catch (IOException e) {
            throw new RuntimeException("Unable to load json [" + fileName + "] from classpath", e);
        } finally {
            IoUtil.closeSilently(inputStream);
        }
    }

    public static String readJsonFromClasspathAsString(String fileName) {
        InputStream inputStream = null;

        try {
            inputStream = IoUtil.getResourceAsStream(fileName);
            if (inputStream == null) {
                throw new RuntimeException("File '" + fileName + "' not found!");
            }

            Scanner s = new java.util.Scanner(inputStream, "UTF-8").useDelimiter("\\A");
            return s.hasNext() ? s.next() : null;
        } finally {
            IoUtil.closeSilently(inputStream);
        }
    }

}