Bug 387414 - adding paging supportrefs/changes/29/7329/1

Created OslcQuery and OslcQueryResult classes.

Change-Id: Ic85b268649da5ee10eb10e35d2add6d20131f70a

6 files changed, 315 insertions, 19 deletions

diff --git a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcClient.java b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcClient.java
index 95e513f..8b30636 100644
--- a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcClient.java
+++ b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcClient.java
@@ -44,6 +44,7 @@ import org.apache.wink.client.ApacheHttpClientConfig;
 import org.apache.wink.client.ClientConfig;
 import org.apache.wink.client.ClientResponse;
 import org.apache.wink.client.RestClient;
+import org.eclipse.lyo.client.oslc.resources.OslcQuery;
 import org.eclipse.lyo.oslc4j.provider.jena.JenaProvidersRegistry;
 import org.eclipse.lyo.oslc4j.provider.json4j.Json4JProvidersRegistry;
 
@@ -51,6 +52,7 @@ import com.hp.hpl.jena.rdf.model.Model;
 import com.hp.hpl.jena.rdf.model.ModelFactory;
 import com.hp.hpl.jena.rdf.model.Property;
 import com.hp.hpl.jena.rdf.model.RDFNode;
+import com.hp.hpl.jena.rdf.model.Resource;
 import com.hp.hpl.jena.rdf.model.Selector;
 import com.hp.hpl.jena.rdf.model.SimpleSelector;
 import com.hp.hpl.jena.rdf.model.Statement;
@@ -113,13 +115,19 @@ public class OslcClient {
 	 * @throws URISyntaxException
 	 */
 	
-	public ClientResponse getResource(String url, String mediaType) throws IOException, OAuthException, URISyntaxException {
+	public ClientResponse getResponse(String url, String mediaType) throws IOException, OAuthException, URISyntaxException {
 		
 
 		RestClient restClient = new RestClient(clientConfig);
 		return restClient.resource(url).accept(mediaType).header("Oslc-Core-Version","2.0").get();
 	}
 	
+	public org.apache.wink.client.Resource getRemoteResource(OslcQuery query) {
+		RestClient restClient = new RestClient(clientConfig);
+		org.apache.wink.client.Resource resource = restClient.resource(query.getCapabilityUrl());
+		return resource;
+	}
+	
 	public class OAuthHttpPool implements HttpClientPool {
 		public HttpClient getHttpClient(URL url) {
 			return httpClient;
@@ -139,7 +147,7 @@ public class OslcClient {
 	public String lookupServiceProviderUrl(String catalogUrl, String serviceProviderTitle) throws IOException, OAuthException, URISyntaxException
 	{
 		String retval = null;
-		ClientResponse response = getResource(catalogUrl,"application/rdf+xml");
+		ClientResponse response = getResponse(catalogUrl,"application/rdf+xml");
 		Model rdfModel = ModelFactory.createDefaultModel();
 
 		rdfModel.read(response.getEntity(InputStream.class),catalogUrl);
@@ -176,7 +184,7 @@ public class OslcClient {
 	public String lookupQueryCapability(String serviceProviderUrl, String oslcDomain) throws IOException, OAuthException, URISyntaxException
 	{
 		String retval = null;
-		ClientResponse response = getResource(serviceProviderUrl,"application/rdf+xml");
+		ClientResponse response = getResponse(serviceProviderUrl,"application/rdf+xml");
 		
 		Model rdfModel = ModelFactory.createDefaultModel();
 		rdfModel.read(response.getEntity(InputStream.class),serviceProviderUrl);
diff --git a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcOAuthClient.java b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcOAuthClient.java
index 10612a9..4f9c7ab 100644
--- a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcOAuthClient.java
+++ b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/OslcOAuthClient.java
@@ -67,7 +67,7 @@ public class OslcOAuthClient extends OslcClient {
 	 * Get an OAuth protected OSLC resource
 	 */
 	@Override
-	public ClientResponse getResource(String url, String mediaType) throws IOException, OAuthException, URISyntaxException
+	public ClientResponse getResponse(String url, String mediaType) throws IOException, OAuthException, URISyntaxException
 	{
 		OAuthMessage message = getResourceInternal(url, HttpMethod.GET, false);
 		
diff --git a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/jazz/JazzRootServicesHelper.java b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/jazz/JazzRootServicesHelper.java
index a90dc73..299fbe5 100644
--- a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/jazz/JazzRootServicesHelper.java
+++ b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/jazz/JazzRootServicesHelper.java
@@ -85,7 +85,7 @@ public class JazzRootServicesHelper {
 	{
 		try {
 			OslcClient rootServicesClient = new OslcClient();
-			ClientResponse response = rootServicesClient.getResource(rootServicesUrl, "application/rdf+xml");
+			ClientResponse response = rootServicesClient.getResponse(rootServicesUrl, "application/rdf+xml");
 			InputStream is = response.getEntity(InputStream.class);
 			Model rdfModel = ModelFactory.createDefaultModel();
 			rdfModel.read(is,rootServicesUrl);
diff --git a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/resources/OslcQuery.java b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/resources/OslcQuery.java
new file mode 100644
index 0000000..e89720f
--- a/dev/null
+++ b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/resources/OslcQuery.java
@@ -0,0 +1,130 @@
+/*******************************************************************************

+ * Copyright (c) 2012 IBM Corporation.

+ *

+ *  All rights reserved. This program and the accompanying materials

+ *  are made available under the terms of the Eclipse Public License v1.0

+ *  and Eclipse Distribution License v. 1.0 which accompanies this distribution.

+ *  

+ *  The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html

+ *  and the Eclipse Distribution License is available at

+ *  http://www.eclipse.org/org/documents/edl-v10.php.

+ *  

+ *  Contributors:

+ *  

+ *     Sean Kennedy     - initial API and implementation

+ *******************************************************************************/

+package org.eclipse.lyo.client.oslc.resources;

+

+import org.apache.wink.client.ClientResponse;

+import org.apache.wink.client.Resource;

+import org.eclipse.lyo.client.oslc.OslcClient;

+

+/**

+ * Represents an OSLC query (HTTP GET) request to be made of a remote system.

+ * 

+ * Immutable.

+ */

+//TODO: Support additional (possibly arbitrary) query parameters

+//		if we need to allow arbitrary query parameters, 

+//		or have too many possible parameters for ease of use in constructors,

+//		decide on some way to allow users to build the parameter list with

+//		multiple statements.

+//	Possible solution: contained static class that has all available parameters

+//	(perhaps with support for arbitrary parameters) that is passed on the 

+//	constructor and held as a final variable.

+public class OslcQuery {

+

+	private final OslcClient oslcClient;

+	

+	private final String capabilityUrl;

+	

+	private String queryUrl;

+	

+	private final int pageSize;

+	

+	private final Resource queryResource;

+	

+	/**

+	 * Create an OSLC query that uses the remote system's default page size.

+	 * 

+	 * @param oslcClient the authenticated OSLC client

+	 * @param capabilityUrl the URL that is the base 

+	 */

+	public OslcQuery(OslcClient oslcClient, String capabilityUrl) {

+		this(oslcClient, capabilityUrl, 0);

+	}

+	

+	/**

+	 * Create an OSLC query that uses the given page size

+	 * 

+	 * @param oslcClient the authenticated OSLC client

+	 * @param capabilityUrl the URL that is the base

+	 * @param pageSize the number of results to include on each page (OslcQueryResult)

+	 */

+	public OslcQuery(OslcClient oslcClient, String capabilityUrl, int pageSize) {

+		this.oslcClient = oslcClient;

+		this.capabilityUrl = capabilityUrl;

+		this.pageSize = (pageSize < 1) ? 0 : pageSize;

+		this.queryResource = createQueryResource();

+		this.queryUrl = null;

+	}

+	

+	OslcQuery(OslcQueryResult previousResult) {

+		this(previousResult.getQuery(), previousResult.getNextPageUrl());

+	}

+	

+	private OslcQuery(OslcQuery previousQuery, String nextPageUrl) {

+		this(previousQuery.oslcClient, previousQuery.capabilityUrl, previousQuery.pageSize);

+		this.queryUrl = nextPageUrl;

+		this.queryResource.uri(nextPageUrl);

+	}

+	

+	private Resource createQueryResource() {

+		Resource resource = oslcClient.getRemoteResource(this);

+		resource.accept("application/rdf+xml");

+		resource.header("Oslc-Core-Version","2.0");

+		applyPagination(resource);

+		return resource;

+	}

+	

+	private void applyPagination(Resource resource) {

+		if (pageSize > 0) {

+			resource.queryParam("oslc.paging", "true");

+			resource.queryParam("oslc.pageSize", pageSize);

+		}

+	}

+

+	/**

+	 * @return the number of entries to return for each page, 

+	 * 		if zero, the remote system's (or full query's) default is used

+	 */

+	public int getPageSize() {

+		return pageSize;

+	}

+

+	/**

+	 * @return the base query capability URL

+	 */

+	public String getCapabilityUrl() {

+		return capabilityUrl;

+	}

+	

+	/**

+	 * @return the complete query URL

+	 */

+	public String getQueryUrl() {

+		if (queryUrl == null) {

+			queryUrl = queryResource.getUriBuilder().build(new Object[0]).toString();

+		}

+		return queryUrl;

+	}

+	

+	public OslcQueryResult submit() {

+		return new OslcQueryResult(this, getResponse());

+	}

+	

+	ClientResponse getResponse() {

+		return queryResource.get();

+	}

+

+}

diff --git a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/resources/OslcQueryResult.java b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/resources/OslcQueryResult.java
new file mode 100644
index 0000000..c34f8b6
--- a/dev/null
+++ b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/resources/OslcQueryResult.java
@@ -0,0 +1,137 @@
+/*******************************************************************************

+ * Copyright (c) 2012 IBM Corporation.

+ *

+ *  All rights reserved. This program and the accompanying materials

+ *  are made available under the terms of the Eclipse Public License v1.0

+ *  and Eclipse Distribution License v. 1.0 which accompanies this distribution.

+ *  

+ *  The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html

+ *  and the Eclipse Distribution License is available at

+ *  http://www.eclipse.org/org/documents/edl-v10.php.

+ *  

+ *  Contributors:

+ *  

+ *     Sean Kennedy     - initial API and implementation

+ *******************************************************************************/

+package org.eclipse.lyo.client.oslc.resources;

+

+import java.io.InputStream;

+import java.util.ArrayList;

+import java.util.Iterator;

+

+import org.apache.wink.client.ClientResponse;

+import org.eclipse.lyo.client.oslc.OSLCConstants;

+import org.eclipse.lyo.oslc4j.core.model.OslcConstants;

+

+import com.hp.hpl.jena.rdf.model.Model;

+import com.hp.hpl.jena.rdf.model.ModelFactory;

+import com.hp.hpl.jena.rdf.model.Property;

+import com.hp.hpl.jena.rdf.model.RDFNode;

+import com.hp.hpl.jena.rdf.model.Resource;

+import com.hp.hpl.jena.rdf.model.Selector;

+import com.hp.hpl.jena.rdf.model.SimpleSelector;

+import com.hp.hpl.jena.rdf.model.Statement;

+import com.hp.hpl.jena.rdf.model.StmtIterator;

+

+

+/**

+ * The results of an OSLC query. If the query was paged, subsequent pages can be retrieved using the Iterator interface.

+ */

+public class OslcQueryResult implements Iterator<OslcQueryResult> {

+

+	private final OslcQuery query;

+

+	private final ClientResponse response;

+	

+	private final int pageNumber;

+	

+	private Model rdfModel;

+	

+	private Resource infoResource, membersResource; 

+	

+	private String nextPageUrl;

+	

+	public OslcQueryResult(OslcQuery query, ClientResponse response) {

+		this.query = query;

+		this.response = response;

+		

+		this.pageNumber = 1;

+		

+		initializeRdf();

+	}

+	

+	private OslcQueryResult(OslcQueryResult prev) {

+		this.query = new OslcQuery(prev);

+		this.response = this.query.getResponse();

+		

+		this.pageNumber = prev.pageNumber + 1;

+		

+		initializeRdf();

+	}

+	

+	private void initializeRdf() {

+		rdfModel = ModelFactory.createDefaultModel();

+		rdfModel.read(response.getEntity(InputStream.class), query.getCapabilityUrl());

+		

+		infoResource = rdfModel.getResource(query.getQueryUrl());

+		membersResource = rdfModel.getResource(query.getCapabilityUrl());

+	}

+	

+	String getNextPageUrl() {

+		if (nextPageUrl == null) {

+			Property predicate = rdfModel.getProperty(OslcConstants.OSLC_CORE_NAMESPACE, "nextPage");

+			Selector select = new SimpleSelector(infoResource, predicate, (RDFNode) null);

+			StmtIterator iter = rdfModel.listStatements(select);

+			if (iter.hasNext()) {

+				Statement nextPage = iter.next();

+				nextPageUrl = nextPage.getResource().getURI();

+			} else {

+				nextPageUrl = "";

+			}

+		}

+		return nextPageUrl;

+	}

+		

+	/**

+	 * @return whether there is another page of results after this

+	 */

+	public boolean hasNext() {

+		return (!"".equals(getNextPageUrl()));

+	}

+

+	/**

+	 * @return the next page of results

+	 * @throws NoSuchElementException if there is no next page

+	 */

+	public OslcQueryResult next() {

+		return new OslcQueryResult(this);

+	}

+

+	/**

+	 * @throws UnsupportedOperationException always

+	 */

+	public void remove() {

+		throw new UnsupportedOperationException();

+	}

+	

+	public OslcQuery getQuery() {

+		return query;

+	}

+

+	public String[] getMembersUrls() {

+		ArrayList<String> membersUrls = new ArrayList<String>();

+		Property predicate = rdfModel.getProperty(OSLCConstants.RDFS, "member");

+		Selector select = new SimpleSelector(membersResource, predicate, (RDFNode) null);

+		StmtIterator iter = rdfModel.listStatements(select);

+		while (iter.hasNext()) {

+			Statement member = iter.next();

+			try {

+				membersUrls.add(member.getResource().getURI());

+			} catch (Throwable t) {

+				//FIXME

+				System.err.println("Member was not a resource");

+			}

+		}

+		return membersUrls.toArray(new String[membersUrls.size()]);

+	}

+}

diff --git a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/samples/JazzFormSample.java b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/samples/JazzFormSample.java
index 00a6e73..d8fb442 100644
--- a/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/samples/JazzFormSample.java
+++ b/org.eclipse.lyo.samples.clients/src/main/java/org/eclipse/lyo/client/oslc/samples/JazzFormSample.java
@@ -30,6 +30,8 @@ import org.eclipse.lyo.client.oslc.OSLCConstants;
 import org.eclipse.lyo.client.oslc.jazz.JazzFormAuthClient;
 import org.eclipse.lyo.client.oslc.jazz.JazzRootServicesHelper;
 import org.eclipse.lyo.client.oslc.resources.ChangeRequest;
+import org.eclipse.lyo.client.oslc.resources.OslcQuery;
+import org.eclipse.lyo.client.oslc.resources.OslcQueryResult;
 
 import org.apache.commons.cli.CommandLine;
 import org.apache.commons.cli.GnuParser;
@@ -82,13 +84,33 @@ public class JazzFormSample {
 				//Get the Query Capabilities URL so that we can run some OSLC queries
 				String queryCapability = client.lookupQueryCapability(serviceProviderUrl,OSLCConstants.OSLC_CM_V2);
 				
+				OslcQuery query = new OslcQuery(client, queryCapability, 5);
+				System.out.println("base query = " + query.getCapabilityUrl());
+				System.out.println("full query = " + query.getQueryUrl());
+				OslcQueryResult result = query.submit();
 				
+				int page = 1;
+				do {
+					System.out.println("Page " + page);
+					for (String resultsUrl : result.getMembersUrls()) {
+						System.out.println(resultsUrl);
+					}
+					if (result.hasNext()) {
+						result = result.next();
+						page++;
+					} else {
+						break;
+					}
+				} while(true);
+				
+				/*
 				//First let's get run a query to get references to 50 workitems (default page size) in the project area.
 				//TODO: Add paging support
 				//To do this, just do a GET on the Query Capability URL	
-				String queryUrl = queryCapability;
-				ClientResponse response = client.getResource(queryUrl,"application/rdf+xml");
-				Collection<String> changeRequestRefs = client.getQueryResponseMembers(queryCapability,response);			
+//				String queryUrl = queryCapability;
+//				ClientResponse response = client.getResponse(queryUrl,"application/rdf+xml");
+				
+				Collection<String> changeRequestRefs = client.getQueryResponseMembers(query.getCapabilityUrl(), response);	
 				
 				//Now, loop through each of the references in the query response and get the actual ChangeRequest
 				//Note: If we could use oslc.select=* with RTC, we would not have to do these followup requests.
@@ -96,7 +118,7 @@ public class JazzFormSample {
 				
 				System.out.println("Getting ready to retrieve " + changeRequestRefs.size() + " change requests");
 				for (String changeRequestRef : changeRequestRefs ) {
-					response = client.getResource(changeRequestRef, "application/rdf+xml");
+					response = client.getResponse(changeRequestRef, "application/rdf+xml");
 					
 					//Marshal as an OSLC4J ChangeRequest.  If you'd prefer the raw XML for the workitem, comment the next 2 lines and
 					//uncomment the code below.
@@ -104,17 +126,16 @@ public class JazzFormSample {
 					printChangeRequestInfo(cr);   //print a few attributes
 					
 					//Uncomment following code if you prefer to work with the raw XML
-					/*
-					InputStream is = response.getEntity(InputStream.class);
-					BufferedReader in = new BufferedReader(new InputStreamReader(is));
-					String line = null;
-					while((line = in.readLine()) != null) {
-					  System.out.println(line);
-					}
-					System.out.println();
-					*/
+//					InputStream is = response.getEntity(InputStream.class);
+//					BufferedReader in = new BufferedReader(new InputStreamReader(is));
+//					String line = null;
+//					while((line = in.readLine()) != null) {
+//					  System.out.println(line);
+//					}
+//					System.out.println();
+					
 				}
-		
+				*/
 				
 			}