Обработка ответа JSON с помощью нового JavaEE7 JSON-P API

/**
 * github-rest
 *
 * Copyright 2015 "GDL Java User Group"
 *
 * 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 mx.gdljug.githubrest.model.json;

import java.io.InputStream;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;

import javax.json.Json;
import javax.json.stream.JsonParser;
import javax.json.stream.JsonParser.Event;

import mx.gdljug.githubrest.model.pojo.Owner;
import mx.gdljug.githubrest.model.pojo.Repository;

/**
 * Parse the github rest service response and transform it 
 * in {@link mx.gdljug.githubrest.model.pojo.Repository} model
 *
 * @author juanitodread
 * @since 1.0
 *
 * Mar 28, 2015
 */
public class ParseRepositoryJsonResponse {

    private InputStream jsonResponse;
    
    private JsonParser jsonParser;
    
    private static final SimpleDateFormat ISO_8601_FORMATTER = new SimpleDateFormat( "yyyy-MM-dd'T'HH:mm:ss'Z'" );
    
    
    /**
     * Instantiate a new ParseRepositoryJsonResponse
     * 
     * @param jsonResponse
     */
    public ParseRepositoryJsonResponse( InputStream jsonResponse ) {
        this.jsonResponse = jsonResponse;
    }

    /**
     * Parse the response of the REST service and return the content in 
     * a collection of Repositories.
     * @return List<Repository>
     */
    public List<Repository> getResositories( ) {
        jsonParser             = Json.createParser( jsonResponse );
        JsonParser.Event evt   = null;
        List<Repository> repos = new ArrayList<>( );
        Repository repo        = null;
        Owner owner            = null;
        
        while(jsonParser.hasNext( )){
            evt = jsonParser.next( );
            
          // First get repository objects
          if(Event.START_OBJECT == evt){    
                repo = new Repository( );
              while(jsonParser.hasNext( )) {
                  evt = jsonParser.next( );
                  if(Event.KEY_NAME != evt && Event.END_OBJECT != evt) {
                      continue;
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "id" )){
                      evt = jsonParser.next( );
                      repo.setId( jsonParser.getLong( ) );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "name" )){
                      evt = jsonParser.next( );                      
                      repo.setName( jsonParser.getString( ) );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "full_name" )){
                      evt = jsonParser.next( );
                      repo.setFullName( jsonParser.getString( ) );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "private" )){
                      evt = jsonParser.next( );
                      repo.setRestricted( Event.VALUE_TRUE == evt );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "html_url" )){
                      evt = jsonParser.next( );
                      repo.setHtmlUrl( jsonParser.getString( ) );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "description" )){
                      evt = jsonParser.next( );
                      repo.setDescription( jsonParser.getString( ) );
                  }
                  if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "created_at" )){
                      evt = jsonParser.next( );
                      try {
                        repo.setCreated( ISO_8601_FORMATTER.parse( jsonParser.getString( ) ) );
                    } catch ( ParseException e ) {
                        e.printStackTrace();
                    }
                  }
                  if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "updated_at" )){
                      evt = jsonParser.next( );
                      try {
                        repo.setUpdated( ISO_8601_FORMATTER.parse( jsonParser.getString( ) ) );
                    } catch ( ParseException e ) {
                        e.printStackTrace();
                    }
                  }
                  else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "git_url" )){
                      evt = jsonParser.next( );
                      repo.setGitUrl( jsonParser.getString( ) );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "language" )){
                      evt = jsonParser.next( );
                      repo.setLanguage( Event.VALUE_NULL != evt ? jsonParser.getString( ) : "" );
                  }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "default_branch" )){
                      evt = jsonParser.next( );
                      repo.setDefaultBranch( jsonParser.getString( ) );
                  }
                  
                  // Get owner objects
                  else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "owner" )) {
                      owner = new Owner( );
                      while(jsonParser.hasNext( )){
                          evt = jsonParser.next( );
                          if(Event.KEY_NAME != evt && Event.END_OBJECT != evt) {
                              continue;
                          } else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "login" )){
                              evt = jsonParser.next( );
                              owner.setUserName( jsonParser.getString( ) );
                          }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "html_url" )){
                              evt = jsonParser.next( );
                              owner.setHtmlUrl( jsonParser.getString( ) );
                          }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "type" )){
                              evt = jsonParser.next( );
                              owner.setType( jsonParser.getString( ) );
                          }else if(Event.KEY_NAME == evt && jsonParser.getString( ).matches( "site_admin" )){
                              evt = jsonParser.next( );
                              owner.setAdmin( Event.VALUE_TRUE == evt );
                          }else if(Event.END_OBJECT == evt ){
                              
                              repo.setOwner( owner );                             
                              break;
                          }
                      }
                  } else if ( Event.END_OBJECT == evt ) {
                      repos.add( repo );
                      break;
                  }
              }
              
          }
        }
        
        return repos;
    }
    
}

/**
 * github-rest
 *
 * Copyright 2015 "GDL Java User Group"
 *
 * 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 mx.gdljug.githubrest;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.stream.Collectors;

import javax.ws.rs.NotFoundException;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.WebTarget;

import mx.gdljug.githubrest.model.json.ParseRepositoryJsonResponse;
import mx.gdljug.githubrest.model.pojo.Repository;

/**
 * Consumes a rest service with all the repositories that a github user
 * has. Also you can filter your response according filters:
 * 
 *      Argument 2: Language filter - Filter a repository according the 
 *                  programming language of the repository.
 *
 * @author juanitodread
 * @since 1.0
 *
 * Mar 28, 2015
 */
public class Main {

    private static final String REST_GITHUB_URL = "https://api.github.com";
    
    private static final String USERS_RESOURCE = "/users/";
    
    private static final String USER_REPOS_RESOURCE = "/repos";
    
    /**
     * Start application
     * 
     * @param args A valid github user name
     * @throws IOException 
     */
    public static void main( String... args ) throws IOException {
        if ( args == null || args.length == 0 || args[0].isEmpty( ) ) {
            throw new IllegalArgumentException( "Invalid github user" );
        }
        
        // Read input arguments
        String githubUser = args[0];
        String language = args.length == 2 ? args[1]: null;
        String userReposResource = String.format( "%s%s%s", USERS_RESOURCE,
                githubUser, USER_REPOS_RESOURCE );
        
        // Invoke REST service
        Client restClient = ClientBuilder.newClient( );
        WebTarget githubRest = restClient.target( REST_GITHUB_URL ).path( userReposResource );
        
        InputStream response = null;
        try {
            response = githubRest.request( ).get( InputStream.class );
        } catch ( NotFoundException ex ) {
            System.out.println( "HTTP 404 Not Found: It seems that your github user does not exist." );
            System.exit( 1 );
        }
        
        // Parse response
        ParseRepositoryJsonResponse githubParserResponse = new ParseRepositoryJsonResponse( response );
        List<Repository> repos = githubParserResponse.getResositories( );

        // User wants filters?
        if ( language != null ) {
            repos = repos.stream( )
                    .filter( x -> x.getLanguage( ).equals( language ) )
                    .collect( Collectors.toList( ) );
        }
        
        // Print response
        repos.forEach( x -> {
            System.out.printf( "-----------------Repository %d------------------%n", x.getId( ) );
            System.out.printf( "| Name: %s%n", x.getName( ) );
            System.out.printf( "| Full name: %s%n", x.getFullName( ) );
            System.out.printf( "| Private: %b%n", x.isRestricted( ) );
            System.out.printf( "| HTML URL: %s%n", x.getHtmlUrl( ) );
            System.out.printf( "| Description: %s%n", x.getDescription( ) );
            System.out.printf( "| Name: %s%n", x.getName( ) );
            System.out.printf( "| Created: %tF %tT:%tL %n", x.getCreated( ), x.getCreated( ), x.getCreated( ) );
            System.out.printf( "| Updated: %tF %tT:%tL %n", x.getUpdated( ), x.getUpdated( ), x.getUpdated( ) );
            System.out.printf( "| Git URL: %s%n", x.getGitUrl( ) );
            System.out.printf( "| Languaje: %s%n", x.getLanguage( ) );
            System.out.printf( "| Default branch: %s%n", x.getDefaultBranch( ) );
            System.out.printf( "| Owner: %n" );
            System.out.printf( "| \tUser name: %s%n", x.getOwner( ).getUserName( ) );
            System.out.printf( "| \tHTML URL: %s%n", x.getOwner( ).getHtmlUrl( ) );
            System.out.printf( "| \tType: %s%n", x.getOwner( ).getType( ) );
            System.out.printf( "| \tAdministrator: %b%n", x.getOwner( ).isAdmin( ) );
            System.out.printf( "-----------------------------------------------------%n%n" );
        } );
    }

}