Simple/Basic Java Rest Web Services Client (with source)

/*

 *

 *  Written by Tom Gutwin - WebARTS Design.

 *  Copyright (C) 2014 WebARTS Design, North Vancouver Canada

 *  http://www.webarts.ca

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; version 3 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without_ even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

package ca.bc.webarts.tools;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.File;

import java.lang.StringBuilder;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLEncoder;

//import android.util.Base64;

import org.apache.commons.codec.binary.Base64;

//import ca.bc.webarts.widgets.Util;

/** A class to encapsulate the calls to Restful Web Services. It is kept very basic with low overhead to live in android apps.

 **/

public class RestRequester

{

  protected static String CLASSNAME = "ca.bc.webarts.tools.RestRequester"; //ca.bc.webarts.widgets.Util.getCurrentClassName();

  public static final String LOG_TAG = CLASSNAME;

  public static boolean debugOut_ = false;

  /**  A holder for this clients System File Separator.  */

  public final static String SYSTEM_FILE_SEPERATOR = File.separator;

  /**  A holder for this clients System line termination separator.  */

  public final static String SYSTEM_LINE_SEPERATOR =

                                           System.getProperty("line.separator");

  protected static String baseUrl_ = ""; // http://isy994

  public static boolean authenticating_ = true;

  protected static String username_ = "";

  protected static String password_ = "";

  protected static boolean acceptJSON_ = false;

  public void setUsername(String uName){username_=uName;}

  public void setPassword(String uPasswd){password_=uPasswd;}

  public void setBaseUrl(String url){baseUrl_=url;}

  public void setAcceptJSON(boolean acceptJson){acceptJSON_=acceptJson;}

  public String getUsername(){return username_;}

  public String getPassword(){return password_;}

  public String getBaseUrl(){return baseUrl_;}

  public boolean getAcceptJSON(){return acceptJSON_;}

  public RestRequester()

  {

  }

  public RestRequester(String baseUrl)

  {

    setBaseUrl( baseUrl);

    authenticating_=false;

  }

  public RestRequester(String baseUrl,String uName,String uPasswd)

  {

    setBaseUrl( baseUrl);

    authenticating_=true;

    setUsername( uName);

    setPassword( uPasswd);

  }

  public boolean isInit()

  {

    boolean retVal = true;

    if( baseUrl_.equals("") ||

        (authenticating_ &&

            (username_.equals("") || password_.equals(""))

        )

      )

      retVal=false;

    return retVal;

  }

  /** Sends the rest service GET request off and retruns the results.

    * @param serviceName is the service (string) to append to the baseURL - example /rest/sys

    * @return the serviceResult as a stringBuilder, null if error

    **/

  public StringBuilder serviceGet(String  serviceName)

  { return callService(serviceName, true);}

  /** Sends the rest service POST request off and retruns the results.

    * @param serviceName is the service (string) to append to the baseURL - example /rest/sys

    * @return the serviceResult as a stringBuilder, null if error

    **/

  public StringBuilder servicePost(String  serviceName)

  { return callService(serviceName, false);}

  /** Sends the rest service request off and retruns the results.

    * @param serviceName is the service (string) to append to the baseURL - example /rest/sys

    * @param getNotPost is a flag to tell this method to do a get or post based on this flag - true does a GET, false does a POST

    * @return the serviceResult as a stringBuilder, null if error

   **/

  public StringBuilder callService(String  serviceName, boolean getNotPost)

  {

    StringBuilder retVal = null;

    if(isInit())

      try

      {

        String usrlStr = (baseUrl_+serviceName).replace(" " ,"%20");

        URL url = new URL(usrlStr);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

        if(getNotPost)

          conn.setRequestMethod("GET");

        else

          conn.setRequestMethod("POST");

        if(acceptJSON_)

          conn.setRequestProperty("Accept", "application/json");

        else

          conn.setRequestProperty("Accept", "application/xml");

        //BASE64Encoder enc = new sun.misc.BASE64Encoder();

        String userpassword = username_ + ":" + password_;

        //String encodedAuthorization = android.util.Base64.encodeToString( userpassword.getBytes(), android.util.Base64.DEFAULT );

        String encodedAuthorization = new String(Base64.encodeBase64( (userpassword.getBytes()) ));

        conn.setRequestProperty("Authorization", "Basic "+ encodedAuthorization);

        if (conn.getResponseCode() == 200)

        {

          BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));

          if (br!=null)

          {

            retVal = new StringBuilder();

            String output;

            if (debugOut_) System.out.println("Output from Server .... \n");

            while ((output = br.readLine()) != null)

            {

              if (debugOut_) System.out.println(output);

              retVal.append(output);

              retVal.append("\n");

            }

          }

        } // valid http response code

        conn.disconnect();

      }

      catch (MalformedURLException e)

      {

       e.printStackTrace();

      }

      catch (IOException e)

      {

         e.printStackTrace();

      }

    return retVal;

  }

  public StringBuilder responseIndenter(StringBuilder sb)

  {

    StringBuilder retVal = new StringBuilder("");

    int indent = -1;

    boolean opening = false;

    boolean closing = false;

    boolean lf = false;

    char [] sbChar = sb.toString().toCharArray();

    for (int i=0; i< sbChar.length;i++)

    {

      opening = false;

      closing = false;

      lf = false;

      if(sbChar[i]=='<')

      {

        indent++;

        opening = true;

        retVal.append("\n");

        for (int j=0;j<indent;j++) retVal.append("  ");

        retVal.append("<");

      }

      else if (sbChar[i]=='/'&&sbChar[i-1]=='<')

      {

        indent--;indent--;

        closing = true;

        retVal.append("/");

      }

      else if (sbChar[i]=='>')

      {

        lf = true;

        retVal.append(">\n");

        for (int j=0;j<indent;j++) retVal.append("  ");

      }

      else

      {

        retVal.append(sbChar[i]);

      }

    }

    return retVal;

  }

}

/*

 *

 *  Written by Tom Gutwin - WebARTS Design.

 *  Copyright (C) 2014 WebARTS Design, North Vancouver Canada

 *  http://www.webarts.ca

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; version 3 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without_ even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

package ca.bc.webarts.tools.isy;

import ca.bc.webarts.tools.RestRequester;

public class ISYRestRequester extends RestRequester

{

  protected static String CLASSNAME = "ca.bc.webarts.tools.ISYRestRequester"; //ca.bc.webarts.widgets.Util.getCurrentClassName();

  private static StringBuffer helpMsg_ = new StringBuffer(SYSTEM_LINE_SEPERATOR);

  public ISYRestRequester()

  {

    setBaseUrl( "http://isy994/rest");

    authenticating_=true;

    setUsername( "admin");

    setPassword( "*******");

  }

  /**

   * Class main commandLine entry method.

   **/

  public static void main(String [] args)

  {

    final String methodName = CLASSNAME + ": main()";

    ISYRestRequester instance = new ISYRestRequester();

    /* Simple way af parsing the args */

    if (args ==null || args.length<1)

      System.out.println(getHelpMsgStr());

    else

    {

      if (args[0].equals("test"))

      {

        System.out.println("Testing ISY Rest Service: "+ "/sys");

        StringBuilder resp =  instance.serviceGet("/sys");

        System.out.println(resp.toString());

        System.out.println();

      }

      else

      {

        // Parse the command

        String allcommands = args[0];

        for (int i=1;i< args.length;i++) allcommands+=" "+args[i];

        System.out.print("Sending ISY Rest Service: "+allcommands);

        String passedCommand = (allcommands.startsWith("/rest/") ? allcommands.substring(5) : allcommands);

        System.out.println(" ("+passedCommand+")");

        StringBuilder resp =  instance.serviceGet(passedCommand);

        if (resp!=null)

        {

          System.out.println(instance.responseIndenter(resp).toString());

          System.out.println();

        }

        else

        {

          System.out.println("Response Error");

          System.out.println();

        }

      }

    }

  } // main

    /** gets the help as a String.

   * @return the helpMsg in String form

   **/

  private static String getHelpMsgStr() {return getHelpMsg().toString();}

  /** initializes and gets the helpMsg_

  class var.

   * @return the class var helpMsg_

   **/

  private static StringBuffer getHelpMsg()

  {

    helpMsg_ = new StringBuffer(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("---  WebARTS ISYRestRequester Class  -----------------------------------------------------");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("---  $Revision:$ $Date:$ ---");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("-------------------------------------------------------------------------------");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("WebARTS ca.bc.webarts.android.ISYRestRequester Class");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("SYNTAX:");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("   java ");

    helpMsg_.append(CLASSNAME);

    helpMsg_.append(" test or restCommand");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("Available Commands:");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("see: http://wiki.universal-devices.com/index.php?title=ISY_Developers:API:REST_Interface");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    helpMsg_.append("---------------------------------------------------------");

    helpMsg_.append("----------------------");

    helpMsg_.append(SYSTEM_LINE_SEPERATOR);

    return helpMsg_;

  }

}