org.springframework.data.hadoop.admin.cli.commands.BaseCommand.java Source code

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Here is the source code for org.springframework.data.hadoop.admin.cli.commands.BaseCommand.java

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/*
 * Copyright 2011-2012 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.data.hadoop.admin.cli.commands;

import java.io.File;

import org.apache.commons.configuration.ConfigurationException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.data.hadoop.admin.cli.util.Log;
import org.springframework.data.hadoop.admin.cli.util.PropertyUtil;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;
import org.springframework.util.FileCopyUtils;
import org.springframework.web.client.RestTemplate;

/**
 * Base class for REST call commands.
 * 
 * @author Jarred Li
 *
 */
public class BaseCommand {

    private String commandURL = "jobs.json";

    public static String errorConnection = "I/O error: Connection refused";

    public static String messageConnection = "Make sure you have set correct service URL, type \"info\" to check service URL."
            + " Or check if the service is working";

    /**
     * call rest service with "Get" 
     */
    public void callGetService() {
        try {
            String json = getJson();
            Log.show(json);
        } catch (Throwable t) {
            showErrorMsg(t);
        }
    }

    /**
     * get JSON from server.
     * 
     * @return JSON String
     */
    public String getJson() {
        RestTemplate template = getRestTemplate();
        String json = template.getForObject(generateCommandUrl(), String.class);
        return json;
    }

    /**
     * @param t
     */
    private void showErrorMsg(Throwable t) {
        if (t.getMessage().contains(errorConnection)) {
            Log.error("call service failed." + messageConnection);
        } else {
            Log.error("call service failed. Reason:" + t.getMessage());
        }
    }

    /**
     * call rest service with "Post" 
     * @param <T>
     */
    public <T> void callPostService(T object) {
        try {
            RestTemplate template = getRestTemplate();
            //      String message = template.postForObject(getCommandUrl(), object, String.class);
            HttpEntity<T> entity = new HttpEntity<T>(object);
            ResponseEntity<String> response = template.exchange(generateCommandUrl(), HttpMethod.POST, entity,
                    String.class);
            String message = response.getBody();
            if (message != null) {
                Log.show(message);
            }
        } catch (Throwable t) {
            showErrorMsg(t);
        }
    }

    /**
     * call rest service with "Delete" 
     * @param object
     */
    public <T> void callDeleteService(T object) {
        try {
            RestTemplate template = getRestTemplate();
            //template.delete(getCommandUrl());
            HttpEntity<T> entity = new HttpEntity<T>(object);
            ResponseEntity<String> response = template.exchange(generateCommandUrl(), HttpMethod.DELETE, entity,
                    String.class);
            String message = response.getBody();
            if (message != null) {
                Log.show(message);
            }
        } catch (Throwable t) {
            showErrorMsg(t);
        }
    }

    /**
     * Download file from server.
     */
    public void callDownloadFile(String fileName) {
        try {
            RestTemplate template = getRestTemplate();
            byte[] bytes = template.getForObject(generateCommandUrl(), byte[].class);
            FileCopyUtils.copy(bytes, new File(fileName));
            Log.show("download file successfully. file name is:" + fileName);
        } catch (Throwable t) {
            showErrorMsg(t);
        }
    }

    /**
     * get RestTempate from xml Beans.
     * 
     * @return
     */
    private RestTemplate getRestTemplate() {
        ApplicationContext context = new ClassPathXmlApplicationContext("rest-context.xml");
        RestTemplate template = context.getBean("restTemplate", RestTemplate.class);
        return template;
    }

    /**
     * get command URL
     * 
     * @return
     */
    private String generateCommandUrl() {
        try {
            String serviceUrl = PropertyUtil.getTargetUrl();
            if (serviceUrl == null || serviceUrl.length() == 0) {
                Log.error("you must set Spring Hadoop Admin service URL first by running target command");
            }
            if (!serviceUrl.endsWith("/")) {
                serviceUrl += "/";
            }
            serviceUrl += getCommandURL();
            return serviceUrl;
        } catch (Exception e) {
            Log.error("get service url failed. " + e.getMessage());
        }
        return null;
    }

    /**
     * @return the commandURL
     */
    public String getCommandURL() {
        return commandURL;
    }

    /**
     * @param commandURL the commandURL to set
     */
    public void setCommandURL(String commandURL) {
        this.commandURL = commandURL;
    }

    /**
     * judge whether service URL is set 
     * 
     * @return true - if service URL is set
     *          false - otherwise
     */
    protected boolean isServiceUrlSet() {
        boolean result = true;
        try {
            String serviceUrl = PropertyUtil.getTargetUrl();
            if (serviceUrl == null || serviceUrl.length() == 0) {
                result = false;
            }
        } catch (ConfigurationException e) {
            Log.error("read properties failed");
            result = false;
        }
        return result;
    }

}