com.ibm.android.asynctask.AsyncServiceTask.java Source code

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Here is the source code for com.ibm.android.asynctask.AsyncServiceTask.java

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/*
 * Copyright 2015 IBM Corp. All Rights Reserved
 * 
 * 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.
 */

/*
    
Abstract class to define tasks that need to be executed Asynchronously
    
 **** Sets a unique string type id for the task
 **** Sets a receiver of the task once it is completed
 *
 * This class extends the android.os.AsyncTask and defines the generic input
 * and output types with String types.
 */

package com.ibm.android.asynctask;

import java.io.IOException;
import java.net.URISyntaxException;

import org.apache.http.client.ClientProtocolException;
import org.apache.http.params.HttpParams;
import org.json.JSONException;

import com.ibm.startkit.android.utility.http.PostService;

import android.os.AsyncTask;

public abstract class AsyncServiceTask extends AsyncTask<String, Void, String> {

    private TaskReceiver _tr = null;

    private String _response;
    private String _serviceID;

    //abstract function to define the Aysnchronous task
    protected abstract String performTask(String... params) throws IOException, JSONException, URISyntaxException;

    //Constructor : assigns the task with a string ID
    public AsyncServiceTask(String serviceID) {
        _serviceID = serviceID;
    }

    @Override
    protected String doInBackground(String... params) {

        try {
            return performTask(params);
        } catch (IOException e) {

            return null;
        } catch (JSONException e) {

            return null;
        } catch (URISyntaxException e) {
            return null;
        }

    }

    /*
       The onPostExecute() is triggered if the asynchronous task is complete.
       The overridden function responds to the event and executes the
       receivers receiveResult() function
    */
    @Override
    protected void onPostExecute(String result) {
        _response = result;
        if (_tr != null) {
            _tr.receiveResult(_response, _serviceID);
        }
    }

    //Sets the receiver of the task completion event
    public void setReceiver(TaskReceiver tr) {
        _tr = tr;
    }

    //utility function to perform a POST method
    public String performPost(String url, String data, HttpParams params, String authString)
            throws ClientProtocolException, URISyntaxException, IOException {

        PostService ps = new PostService(params);
        return ps.performPost(url, data);
    }

}