EchoProcessExample.java

/**
 * Copyright (C) 2007 - 2016 52°North Initiative for Geospatial Open Source
 * Software 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.n52.wps.client.example;

import java.io.IOException;
import java.util.Random;

import javax.xml.transform.TransformerException;

import net.opengis.wps.x100.ExecuteDocument;
import net.opengis.wps.x100.ExecuteResponseDocument;
import net.opengis.wps.x100.ProcessDescriptionType;

import org.apache.xpath.XPathAPI;
import org.apache.xpath.objects.XObject;
import org.n52.wps.client.ExecuteRequestBuilder;
import org.n52.wps.client.WPSClientException;
import org.n52.wps.client.WPSClientSession;

public class EchoProcessExample {

    private String url = "http://localhost:8080/wps/WebProcessingService";

    private String processID = "org.n52.wps.server.algorithm.test.EchoProcess";

    private Random rand = new Random();

    public static void main(String[] args) {
        EchoProcessExample example = new EchoProcessExample();
        try {
            example.run();
        }
        catch (IOException e) {
            e.printStackTrace();
        }
        catch (WPSClientException e) {
            e.printStackTrace();
        }
        catch (TransformerException e) {
            e.printStackTrace();
        }
    }

    private void run() throws IOException, WPSClientException, TransformerException {
        System.out.println("EchoProcess Example");

        // connect session
        WPSClientSession wpsClient = WPSClientSession.getInstance();
        boolean connected = wpsClient.connect(url);
        if ( !connected) {
            System.out.println("Could not connect to WPS.");
            return;
        }

        // take a look at the process description
        ProcessDescriptionType processDescription = wpsClient.getProcessDescription(url, processID);
        System.out.println("Echo process description:\n" + processDescription.xmlText() + "\n");

        // create the request, add literal input
        ExecuteRequestBuilder executeBuilder = new ExecuteRequestBuilder(processDescription);
        String input = "Hello lucky number " + rand.nextInt(42) + "!";
        String parameterIn = "literalInput";
        executeBuilder.addLiteralData(parameterIn, input);
        String parameterOut = "literalOutput";
        executeBuilder.setResponseDocument(parameterOut, null, null, null);

        if ( !executeBuilder.isExecuteValid())
            System.out.println("Created execute request is NOT valid.");

        // build and send the request document
        ExecuteDocument executeRequest = executeBuilder.getExecute();
        System.out.println("Sending execute request:\n" + executeRequest.xmlText() + "\n");
        Object response = wpsClient.execute(url, executeRequest);
        System.out.println("Got response:\n" + response.toString() + "\n");

        // compare input and output
        if (response instanceof ExecuteResponseDocument) {
            ExecuteResponseDocument responseDoc = (ExecuteResponseDocument) response;
            XObject data = XPathAPI.eval(responseDoc.getDomNode(), "//wps:LiteralData");
            String output = data.toString();
            if (output.equals(input))
                System.out.println("Echo received!");
        }
    }
}