Develop Reference

Twitter Java project : failed to establish connection properly

I am trying to consume Twitter streams with the help of a Java Kafka application.
I have created a Twitter developer account and a Twitter application and generated all the 4 keys required.
Please find the code below:
package com.github.simpleanand.kafkabeginner.tutorial2;
import java.util.List;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.TimeUnit;
import org.apache.http.HttpHost;
import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.impl.client.DefaultHttpClient;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.collect.Lists;
import com.twitter.hbc.ClientBuilder;
import com.twitter.hbc.core.Client;
import com.twitter.hbc.core.Constants;
import com.twitter.hbc.core.Hosts;
import com.twitter.hbc.core.HttpHosts;
import com.twitter.hbc.core.endpoint.StatusesFilterEndpoint;
import com.twitter.hbc.core.processor.StringDelimitedProcessor;
import com.twitter.hbc.httpclient.auth.Authentication;
import com.twitter.hbc.httpclient.auth.OAuth1;
public class TwitterProducer {
private Logger logger = LoggerFactory.getLogger(TwitterProducer.class);
private String consumerKey = "<consumer-key>";
private String consumerSecret = "<consumerSecret>";
private String token = "<token value>";
private String secret = "<secret>";
public TwitterProducer() {
}
public static void main(String[] args) {
new TwitterProducer().run();
}
public void run() {
logger.info("inside run........");
// create a twitter client
/**
* Set up your blocking queues: Be sure to size these properly based on
* expected TPS of your stream
*/
BlockingQueue<String> msgQueue = new LinkedBlockingQueue<String>(100000);
Client client = createTwitterClient(msgQueue);
client.connect();
// create a kafka producer
// loop to send tweets to kafka
// on a different thread, or multiple different threads....
while (!client.isDone()) {
String msg = null;
try {
msg = msgQueue.poll(5, TimeUnit.SECONDS);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
client.stop();
}
if (null != msg) {
logger.info("Msg -> " + msg);
}
}
logger.info("end of application........");
}
public Client createTwitterClient(BlockingQueue<String> msgQueue) {
HttpHost proxy = new HttpHost("<compayny proxy value>", 8080);
DefaultHttpClient httpClient = new DefaultHttpClient();
httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
/**
* Declare the host you want to connect to, the endpoint, and
* authentication (basic auth or oauth)
*/
Hosts hosebirdHosts = new HttpHosts(Constants.STREAM_HOST);
StatusesFilterEndpoint hosebirdEndpoint = new StatusesFilterEndpoint();
// Optional: set up some followings and track terms
// List<Long> followings = Lists.newArrayList(1234L, 566788L);
List<String> terms = Lists.newArrayList("bitcoin");
// hosebirdEndpoint.followings(followings);
hosebirdEndpoint.trackTerms(terms);
// These secrets should be read from a config file
Authentication hosebirdAuth = new OAuth1(consumerKey, consumerSecret, token, secret);
hosebirdAuth.setupConnection(httpClient);
// Creating a client:
ClientBuilder builder = new ClientBuilder().name("Hosebird-Client-01") // optional:
// mainly
// for
// the
// logs
.hosts(hosebirdHosts).authentication(hosebirdAuth).endpoint(hosebirdEndpoint)
.processor(new StringDelimitedProcessor(msgQueue));
Client hosebirdClient = builder.build();
// Attempts to establish a connection.
return hosebirdClient;
}
}
I'm getting the following error:
[hosebird-client-io-thread-0] INFO com.twitter.hbc.httpclient.ClientBase - Hosebird-Client-01 Establishing a connection
[hosebird-client-io-thread-0] WARN com.twitter.hbc.httpclient.ClientBase - Hosebird-Client-01 Unknown host - stream.twitter.com
[hosebird-client-io-thread-0] WARN com.twitter.hbc.httpclient.ClientBase - Hosebird-Client-01 failed to establish connection properly
[hosebird-client-io-thread-0] INFO com.twitter.hbc.httpclient.ClientBase - Hosebird-Client-01 Done processing, preparing to close connection
Please advise on how to solve this error.
It seems there is an issue of proxy object being sent.It that correct?

Problems with LDAP authentication: java.lang.IncompatibleClassChangeError

I've got a class that allows me to authenticate with LDAP. When i run this code in a project with just one class (for testing reasons) i don't have problems and it returns a boolean value, as is expected, but when i run it in the project i'm working in, i got the following error:
java.lang.IncompatibleClassChangeError: Class org.apache.mina.filter.codec.ProtocolCodecFilter does not implement the requested interface org.apache.mina.core.filterchain.IoFilter
This is the method the allows me to authenticate:
public static void autenticarUsuario(String usuar, String password) throws LdapException, CursorException{
Dn user = Dn.EMPTY_DN;
try{
BasicConfigurator.configure();
LdapConnectionConfig config = new LdapConnectionConfig();
config.setLdapHost(SERVER_IP);
config.setLdapPort(PORT);
config.setName("uid=ldapsearch,ou=System,ou=Users,dc=fiec,dc=espol,dc=edu,dc=ec");
config.setCredentials(CREDENTIALS);
conn = new LdapNetworkConnection(config);
}catch(Exception e){
}
String s1 = usuar;
String s2 = password;
//System.out.println("Nombre: "+s1+" Contra: "+s2);
try {
conn.bind();
System.out.println(conn.isAuthenticated());
// Create the SearchRequest object
SearchRequest req = new SearchRequestImpl();
req.setScope( SearchScope.SUBTREE );
req.addAttributes( "*" );
req.setTimeLimit( 0 );
req.setBase( new Dn( "ou=Users,dc=fiec,dc=espol,dc=edu,dc=ec" ) );
req.setFilter( "(uid="+ s1 +")" );
// Process the request
SearchCursor searchCursor = conn.search( req );
while ( searchCursor.next() )
{
Response r = searchCursor.get();
if(r instanceof SearchResultEntry){
Entry re = ((SearchResultEntry) r).getEntry();
user = re.getDn();
}
}
conn.bind(user, s2);
//return(conn.isAuthenticated());
inLDAP = conn.isAuthenticated();
} catch (InvalidConnectionException ex) {
//System.out.println(ex);
}
catch (LdapException e) {
e.printStackTrace();
} catch (CursorException e) {
e.printStackTrace();
}
inLDAP = false;
}
The project i'm working in is a JAVAFX application, but this method is called in a class that doesn't extend from application (just java code to verify user credentials).
This is the stacktrace:
Exception in thread "pool-1-thread-1" java.lang.IncompatibleClassChangeError: Class org.apache.mina.filter.codec.ProtocolCodecFilter does not implement the requested interface org.apache.mina.core.filterchain.IoFilter
at org.apache.mina.core.filterchain.DefaultIoFilterChain.register(DefaultIoFilterChain.java:267)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.addLast(DefaultIoFilterChain.java:174)
at org.apache.mina.core.filterchain.DefaultIoFilterChainBuilder.buildFilterChain(DefaultIoFilterChainBuilder.java:436)
at org.apache.mina.core.polling.AbstractPollingIoProcessor.addNow(AbstractPollingIoProcessor.java:528)
at org.apache.mina.core.polling.AbstractPollingIoProcessor.handleNewSessions(AbstractPollingIoProcessor.java:501)
at org.apache.mina.core.polling.AbstractPollingIoProcessor.access$400(AbstractPollingIoProcessor.java:67)
at org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor.run(AbstractPollingIoProcessor.java:1116)
at org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:51)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
These are the libraries i'm working:
import org.apache.directory.api.ldap.model.cursor.CursorException;
import org.apache.directory.api.ldap.model.cursor.SearchCursor;
import org.apache.directory.api.ldap.model.entry.Entry;
import org.apache.directory.api.ldap.model.exception.LdapException;
import org.apache.directory.api.ldap.model.message.Response;
import org.apache.directory.api.ldap.model.message.SearchRequest;
import org.apache.directory.api.ldap.model.message.SearchRequestImpl;
import org.apache.directory.api.ldap.model.message.SearchResultEntry;
import org.apache.directory.api.ldap.model.message.SearchScope;
import org.apache.directory.api.ldap.model.name.Dn;
import org.apache.directory.ldap.client.api.LdapConnection;
import org.apache.directory.ldap.client.api.LdapConnectionConfig;
import org.apache.mina.*;
import org.apache.directory.ldap.client.api.LdapNetworkConnection;
import org.apache.directory.ldap.client.api.exception.InvalidConnectionException;
import org.apache.log4j.BasicConfigurator;
I don't know why this is happening, i'll appreciate any help in advance

It is a version problem. Between Mina 1.0 and Mina 2.0, they moved the IoFilter interface (among other things) from org.apache.mina.filterchain to org.apache.mina.core.filterchain. I think you are trying to use code compiled for Mina 2.0 with the Mina 1.0 implementation.
Solution: examine your build and runtime classpaths and dependencies to figure out how this happened ... and fix the inconsistency.

ETrade Java API issue - previewEquityOrder and previewOptionOrder throw an ETWSException

I am working with the ETrade Java API. I was able to use most of the functions but I am having trouble with the previewEquityOrder and the previewOptionOrder functions. Here are the error messages/ exceptions I get when I call these functions:
URL : https://etwssandbox.etrade.com/order/sandbox/rest/previewequityorder
? Java exception occurred:
com.etrade.etws.sdk.common.ETWSException
at com.etrade.etws.sdk.common.ETWSUtil.constructException(ETWSUtil.java:9)
at com.etrade.etws.sdk.core.ConnectionUtils.invoke(ConnectionUtils.java:90)
at com.etrade.etws.sdk.core.ConnectionUtils.invoke(ConnectionUtils.java:32)
at com.etrade.etws.sdk.client.OrderClient.previewEquityOrder(OrderClient.java:145)
For the previewOptionOrder:
URL : https://etwssandbox.etrade.com/order/sandbox/rest/previewoptionorder
? Java exception occurred:
com.etrade.etws.sdk.common.ETWSException
at com.etrade.etws.sdk.common.ETWSUtil.constructException(ETWSUtil.java:9)
at com.etrade.etws.sdk.core.ConnectionUtils.invoke(ConnectionUtils.java:90)
at com.etrade.etws.sdk.core.ConnectionUtils.invoke(ConnectionUtils.java:32)
at com.etrade.etws.sdk.client.OrderClient.previewOptionOrder(OrderClient.java:167)
The following Java code can reproduce the problem. You can compile this code on a Mac using the following command. On windows machine, replace the " : " with " ; " as the separator.
javac -classpath "./commons-codec-1.3.jar:./commons-httpclient-3.1.jar:./commons-httpclient-contrib-ssl-3.1.jar:./commons-lang-2.4-javadoc.jar:./commons-lang-2.4-sources.jar:./commons-lang-2.4.jar:./commons-logging-api.jar:./commons-logging.jar:./etws-accounts-sdk-1.0.jar:./etws-common-connections-1.0.jar:./etws-market-sdk-1.0.jar:./etws-oauth-sdk-1.0.jar:./etws-order-sdk-1.0.jar:./log4j-1.2.15.jar:./xstream-1.3.1.jar:" test.java
You can run the compiled class from command line using the following command:
java -classpath "./commons-codec-1.3.jar:./commons-httpclient-3.1.jar:./commons-httpclient-contrib-ssl-3.1.jar:./commons-lang-2.4-javadoc.jar:./commons-lang-2.4-sources.jar:./commons-lang-2.4.jar:./commons-logging-api.jar:./commons-logging.jar:./etws-accounts-sdk-1.0.jar:./etws-common-connections-1.0.jar:./etws-market-sdk-1.0.jar:./etws-oauth-sdk-1.0.jar:./etws-order-sdk-1.0.jar:./log4j-1.2.15.jar:./xstream-1.3.1.jar:" test <consumer_key> <consumer_secret>
You will need to pass in the ETrade consumer key and consumer secret as command line arguments to run this.
Notice that the authentication part works which is verified by getting the accounts list.
import com.etrade.etws.account.Account;
import com.etrade.etws.account.AccountListResponse;
import com.etrade.etws.oauth.sdk.client.IOAuthClient;
import com.etrade.etws.oauth.sdk.client.OAuthClientImpl;
import com.etrade.etws.oauth.sdk.common.Token;
import com.etrade.etws.sdk.client.ClientRequest;
import com.etrade.etws.sdk.client.Environment;
import com.etrade.etws.sdk.common.ETWSException;
import com.etrade.etws.sdk.client.AccountsClient;
import com.etrade.*;
import com.etrade.etws.order.PreviewEquityOrder;
import com.etrade.etws.order.PreviewEquityOrderResponse;
import com.etrade.etws.order.EquityOrderRequest;
import com.etrade.etws.order.EquityOrderTerm;
import com.etrade.etws.order.EquityOrderAction;
import com.etrade.etws.order.MarketSession;
import com.etrade.etws.order.EquityPriceType;
import com.etrade.etws.order.EquityOrderRoutingDestination;
import com.etrade.etws.sdk.client.OrderClient;
import java.math.BigInteger;
import java.awt.Desktop;
import java.net.URI;
import java.*;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;
public class test
{
public static void main(String[] args) throws IOException, ETWSException
{
//Variables
if(args.length<2){
System.out.println("Class test needs two input argument as follows:");
System.out.println("test <consumer_key> <consumer_secret>");
return;
}
String oauth_consumer_key = args[0]; // Your consumer key
String oauth_consumer_secret = args[1]; // Your consumer secret
String oauth_request_token = null; // Request token
String oauth_request_token_secret = null; // Request token secret
String oauth_verify_code = null;
String oauth_access_token = null;
String oauth_access_token_secret = null;
ClientRequest request = new ClientRequest();
System.out.println("HERE");
IOAuthClient client = OAuthClientImpl.getInstance(); // Instantiate IOAUthClient
// Instantiate ClientRequest
request.setEnv(Environment.SANDBOX); // Use sandbox environment
request.setConsumerKey(oauth_consumer_key); //Set consumer key
request.setConsumerSecret(oauth_consumer_secret);
Token token = client.getRequestToken(request); // Get request-token object
oauth_request_token = token.getToken(); // Get token string
oauth_request_token_secret = token.getSecret(); // Get token secret
request.setToken(oauth_request_token);
request.setTokenSecret(oauth_request_token_secret);
String authorizeURL = null;
authorizeURL = client.getAuthorizeUrl(request);
System.out.println(authorizeURL);
System.out.println("Copy the URL into your browser. Get the verification code and type here");
oauth_verify_code = get_verification_code();
//oauth_verify_code = Verification(client,request);
request.setVerifierCode(oauth_verify_code);
token = client.getAccessToken(request);
oauth_access_token = token.getToken();
oauth_access_token_secret = token.getSecret();
request.setToken(oauth_access_token);
request.setTokenSecret(oauth_access_token_secret);
// Get Account List
AccountsClient account_client = new AccountsClient(request);
AccountListResponse response = account_client.getAccountList();
List<Account> alist = response.getResponse();
Iterator<Account> al = alist.iterator();
while (al.hasNext()) {
Account a = al.next();
System.out.println("===================");
System.out.println("Account: " + a.getAccountId());
System.out.println("===================");
}
// Preview Equity Order
OrderClient order_client = new OrderClient(request);
PreviewEquityOrder orderRequest = new PreviewEquityOrder();
EquityOrderRequest eor = new EquityOrderRequest();
eor.setAccountId("83405188"); // sample values
eor.setSymbol("AAPL");
eor.setAllOrNone("FALSE");
eor.setClientOrderId("asdf1234");
eor.setOrderTerm(EquityOrderTerm.GOOD_FOR_DAY);
eor.setOrderAction(EquityOrderAction.BUY);
eor.setMarketSession(MarketSession.REGULAR);
eor.setPriceType(EquityPriceType.MARKET);
eor.setQuantity(new BigInteger("100"));
eor.setRoutingDestination(EquityOrderRoutingDestination.AUTO.value());
eor.setReserveOrder("TRUE");
orderRequest.setEquityOrderRequest(eor);
PreviewEquityOrderResponse order_response = order_client.previewEquityOrder(orderRequest);
}
public static String get_verification_code() {
try{
BufferedReader br =
new BufferedReader(new InputStreamReader(System.in));
String input;
input=br.readLine();
return input;
}catch(IOException io){
io.printStackTrace();
return "";
}
}
}
I posted this on the ETrade community forum but that forum is not very active. I also sent a request to ETrade and haven't gotten a reply yet. If I get a solution from them, I will come back and post it here. In the mean time any help is greatly appreciated.

After debugging my above code, I figured out that the problem is that I was setting the ReserveOrder to TRUE but I wasn't providing the required ReserveOrderQuantity. I got the above code from the Java code snippet in the ETrade Developer Platform Guide. This is clearly a bug in their documentation.

Using NTLM authentication in Java applications

I want to use Windows NTLM authentication in my Java application to authenticate intranet users transparently. The users should not notice any authentication if using their browsers (single sign-on).
I've found a few libs with NTLM support, but don't know which one to use:
http://spnego.sourceforge.net/
http://sourceforge.net/projects/ntlmv2auth/
http://jcifs.samba.org/
http://www.ioplex.com/jespa.html
http://www.luigidragone.com/software/ntlm-authentication-in-java/
Any suggestions where to start?

Out of the above list, only ntlmv2-auth and Jespa support NTLMv2. Jespa is workable but commercial. ntlmv2-auth I haven't tried but it's based on the code from Liferay, which I've seen working before.
'ntlm-authentication-in-java' is only NTLMv1, which is old, insecure, and works in a dwindling number of environments as people upgrade to newer Windows versions. JCIFS used to have an NTLMv1 HTTP auth filter, but it was removed in later versions, as the way it was implemented amounts to a man-in-the-middle attack on the insecure protocol. (The same appears to be true of 'ntlm-authentication-in-java'.)
The 'spnego' project is Kerberos not NTLM. If you want to replicate full IWA as IIS does it, you'd need to support both NTLMv2 and Kerberos ('NTLM' auth, 'Negotiate' auth, NTLMSSP-in-SPNego auth and NTLM-masquerading-as-Negotiate auth).

Luigi Dragone's script is really old and seems to always fail.
HttpURLConnection can work with NTLM if you add library jcifs, this example works with latest jcifs-1.3.18 :
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.UnknownHostException;
import java.util.HashMap;
import java.util.Map;
import org.apache.http.impl.auth.NTLMEngineException;
public class TestNTLMConnection {
public static void main(String[] args) throws UnknownHostException, IOException, NTLMEngineException {
// Method 1 : authentication in URL
jcifs.Config.registerSmbURLHandler();
URL urlRequest = new URL("http://domain%5Cuser:pass#127.0.0.1/");
// or Method 2 : authentication via System.setProperty()
// System.setProperty("http.auth.ntlm.domain", "domain");
// System.setProperty("jcifs.smb.client.domain", "domain");
// System.setProperty("jcifs.smb.client.username", "user");
// System.setProperty("jcifs.smb.client.password", "pass");
// Not verified // System.setProperty("jcifs.netbios.hostname", "host");
// System.setProperty("java.protocol.handler.pkgs", "jcifs");
// URL urlRequest = new URL("http://127.0.0.1:8180/simulate_get.php");
HttpURLConnection conn = (HttpURLConnection) urlRequest.openConnection();
StringBuilder response = new StringBuilder();
try {
InputStream stream = conn.getInputStream();
BufferedReader in = new BufferedReader(new InputStreamReader(stream));
String str = "";
while ((str = in.readLine()) != null) {
response.append(str);
}
in.close();
System.out.println(response);
} catch(IOException err) {
System.out.println(err);
} finally {
Map<String, String> msgResponse = new HashMap<String, String>();
for (int i = 0;; i++) {
String headerName = conn.getHeaderFieldKey(i);
String headerValue = conn.getHeaderField(i);
if (headerName == null && headerValue == null) {
break;
}
msgResponse.put(headerName == null ? "Method" : headerName, headerValue);
}
System.out.println(msgResponse);
}
}
}
And if you are curious about the content of each handshake, you can find another example using jcifs and Socket on this thread.

Had to recently implement this at work hence here is updated solution with Spring's RestTemplate:
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.NTCredentials;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.client.HttpClients;
import org.springframework.http.HttpEntity;
import org.springframework.http.ResponseEntity;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;
import java.io.IOException;
public class Runner {
public static void main(String[] args) {
var credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new NTCredentials("username", "password", "", "someDomain"));
try (var client = HttpClients.custom()
.setDefaultCredentialsProvider(credentialsProvider)
.build();) {
var requestFactory = new HttpComponentsClientHttpRequestFactory();
requestFactory.setHttpClient(client);
RestTemplate restTemplate = new RestTemplate(requestFactory);
ResponseEntity<String> stringResponseEntity = restTemplate.postForEntity("url", new HttpEntity<>("yourDtoObject"), String.class);
} catch (IOException e) {
e.printStackTrace();
}
}
}
dependencies needed are: spring-web and org.apache.httpcomponents
ps: it is important to enter username without domain otherwise it doesn't work. As in if your domain is companyName/username often people just enter that whole thing as username and what you should do is enter them separately where domain="companyName" and username="username"

Ref: https://jcifs.samba.org/src/docs/faq.html#ntlmv2
Q: Does jCIFS support NTLMv2?
A: Yes. As of 1.3.0, JCIFS fully supports NTLMv2 and uses it by default.
Note: The NTLM HTTP SSO Filter that used to be included with JCIFS cannot support NTLMv2.

Relatively from the list you gave,I would go with JCIFS.
The library is mature , and their documentation is good.
To top it off they had fairly regular releases , and the last one being Nov 2011.
Personal Experience : it was fairly easy to get started when compared to others i have tried (spnego and ntmv2auth)

Amazon Product Advertising API through Java/SOAP

I have been playing with Amazon's Product Advertising API, and I cannot get a request to go through and give me data. I have been working off of this: http://docs.amazonwebservices.com/AWSECommerceService/2011-08-01/GSG/ and this: Amazon Product Advertising API signed request with Java
Here is my code. I generated the SOAP bindings using this: http://docs.amazonwebservices.com/AWSECommerceService/2011-08-01/GSG/YourDevelopmentEnvironment.html#Java
On the Classpath, I only have: commons-codec.1.5.jar
import com.ECS.client.jax.AWSECommerceService;
import com.ECS.client.jax.AWSECommerceServicePortType;
import com.ECS.client.jax.Item;
import com.ECS.client.jax.ItemLookup;
import com.ECS.client.jax.ItemLookupRequest;
import com.ECS.client.jax.ItemLookupResponse;
import com.ECS.client.jax.ItemSearchResponse;
import com.ECS.client.jax.Items;
public class Client {
public static void main(String[] args) {
String secretKey = <my-secret-key>;
String awsKey = <my-aws-key>;
System.out.println("API Test started");
AWSECommerceService service = new AWSECommerceService();
service.setHandlerResolver(new AwsHandlerResolver(
secretKey)); // important
AWSECommerceServicePortType port = service.getAWSECommerceServicePort();
// Get the operation object:
com.ECS.client.jax.ItemSearchRequest itemRequest = new com.ECS.client.jax.ItemSearchRequest();
// Fill in the request object:
itemRequest.setSearchIndex("Books");
itemRequest.setKeywords("Star Wars");
// itemRequest.setVersion("2011-08-01");
com.ECS.client.jax.ItemSearch ItemElement = new com.ECS.client.jax.ItemSearch();
ItemElement.setAWSAccessKeyId(awsKey);
ItemElement.getRequest().add(itemRequest);
// Call the Web service operation and store the response
// in the response object:
com.ECS.client.jax.ItemSearchResponse response = port
.itemSearch(ItemElement);
String r = response.toString();
System.out.println("response: " + r);
for (Items itemList : response.getItems()) {
System.out.println(itemList);
for (Item item : itemList.getItem()) {
System.out.println(item);
}
}
System.out.println("API Test stopped");
}
}
Here is what I get back.. I was hoping to see some Star Wars books available on Amazon dumped out to my console :-/:
API Test started
response: com.ECS.client.jax.ItemSearchResponse#7a6769ea
com.ECS.client.jax.Items#1b5ac06e
API Test stopped
What am I doing wrong (Note that no "item" in the second for loop is being printed out, because its empty)? How can I troubleshoot this or get relevant error information?

I don't use the SOAP API but your Bounty requirements didn't state that it had to use SOAP only that you wanted to call Amazon and get results. So, I'll post this working example using the REST API which will at least fulfill your stated requirements:
I would like some working example code that hits the amazon server and returns results
You'll need to download the following to fulfill the signature requirements:
http://associates-amazon.s3.amazonaws.com/signed-requests/samples/amazon-product-advt-api-sample-java-query.zip
Unzip it and grab the com.amazon.advertising.api.sample.SignedRequestsHelper.java file and put it directly into your project. This code is used to sign the request.
You'll also need to download Apache Commons Codec 1.3 from the following and add it to your classpath i.e. add it to your project's library. Note that this is the only version of Codec that will work with the above class (SignedRequestsHelper)
http://archive.apache.org/dist/commons/codec/binaries/commons-codec-1.3.zip
Now you can copy and paste the following making sure to replace your.pkg.here with the proper package name and replace the SECRET and the KEY properties:
package your.pkg.here;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;
public class Main {
private static final String SECRET_KEY = "<YOUR_SECRET_KEY>";
private static final String AWS_KEY = "<YOUR_KEY>";
public static void main(String[] args) {
SignedRequestsHelper helper = SignedRequestsHelper.getInstance("ecs.amazonaws.com", AWS_KEY, SECRET_KEY);
Map<String, String> params = new HashMap<String, String>();
params.put("Service", "AWSECommerceService");
params.put("Version", "2009-03-31");
params.put("Operation", "ItemLookup");
params.put("ItemId", "1451648537");
params.put("ResponseGroup", "Large");
String url = helper.sign(params);
try {
Document response = getResponse(url);
printResponse(response);
} catch (Exception ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}
}
private static Document getResponse(String url) throws ParserConfigurationException, IOException, SAXException {
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(url);
return doc;
}
private static void printResponse(Document doc) throws TransformerException, FileNotFoundException {
Transformer trans = TransformerFactory.newInstance().newTransformer();
Properties props = new Properties();
props.put(OutputKeys.INDENT, "yes");
trans.setOutputProperties(props);
StreamResult res = new StreamResult(new StringWriter());
DOMSource src = new DOMSource(doc);
trans.transform(src, res);
String toString = res.getWriter().toString();
System.out.println(toString);
}
}
As you can see this is much simpler to setup and use than the SOAP API. If you don't have a specific requirement for using the SOAP API then I would highly recommend that you use the REST API instead.
One of the drawbacks of using the REST API is that the results aren't unmarshaled into objects for you. This could be remedied by creating the required classes based on the wsdl.

This ended up working (I had to add my associateTag to the request):
public class Client {
public static void main(String[] args) {
String secretKey = "<MY_SECRET_KEY>";
String awsKey = "<MY AWS KEY>";
System.out.println("API Test started");
AWSECommerceService service = new AWSECommerceService();
service.setHandlerResolver(new AwsHandlerResolver(secretKey)); // important
AWSECommerceServicePortType port = service.getAWSECommerceServicePort();
// Get the operation object:
com.ECS.client.jax.ItemSearchRequest itemRequest = new com.ECS.client.jax.ItemSearchRequest();
// Fill in the request object:
itemRequest.setSearchIndex("Books");
itemRequest.setKeywords("Star Wars");
itemRequest.getResponseGroup().add("Large");
// itemRequest.getResponseGroup().add("Images");
// itemRequest.setVersion("2011-08-01");
com.ECS.client.jax.ItemSearch ItemElement = new com.ECS.client.jax.ItemSearch();
ItemElement.setAWSAccessKeyId(awsKey);
ItemElement.setAssociateTag("th0426-20");
ItemElement.getRequest().add(itemRequest);
// Call the Web service operation and store the response
// in the response object:
com.ECS.client.jax.ItemSearchResponse response = port
.itemSearch(ItemElement);
String r = response.toString();
System.out.println("response: " + r);
for (Items itemList : response.getItems()) {
System.out.println(itemList);
for (Item itemObj : itemList.getItem()) {
System.out.println(itemObj.getItemAttributes().getTitle()); // Title
System.out.println(itemObj.getDetailPageURL()); // Amazon URL
}
}
System.out.println("API Test stopped");
}
}

It looks like the response object does not override toString(), so if it contains some sort of error response, simply printing it will not tell you what the error response is. You'll need to look at the api for what fields are returned in the response object and individually print those. Either you'll get an obvious error message or you'll have to go back to their documentation to try to figure out what is wrong.

You need to call the get methods on the Item object to retrieve its details, e.g.:
for (Item item : itemList.getItem()) {
System.out.println(item.getItemAttributes().getTitle()); //Title of item
System.out.println(item.getDetailPageURL()); // Amazon URL
//etc
}
If there are any errors you can get them by calling getErrors()
if (response.getOperationRequest().getErrors() != null) {
System.out.println(response.getOperationRequest().getErrors().getError().get(0).getMessage());
}