Running Hbase with Java Servlets

Question

I wrote a Hbase Java basic code that works fine with Java.

public class HBaseTest {

    public static String newFunc() throws IOException {

        // Instantiating configuration class
        Configuration config = HBaseConfiguration.create();

        Connection connection = ConnectionFactory.createConnection(config);
        Table table = connection.getTable(TableName.valueOf("customer"));

        Get g = new Get(Bytes.toBytes("jsmith"));

        Result result = table.get(g);

        // Reading values from Result class object
        byte[] value = result.getValue(Bytes.toBytes("addr"), Bytes.toBytes("city"));

        return Bytes.toString(value);

    }
}

So I decided to use this code and Hbase as a part of my web application development and so I opened a new Dynamic Web Project in Eclipse Java EE IDE and added this file, changed the name of function and called it from one of the servlets. I also added the required jar files. But I am stuck with the following error:

java.lang.ClassNotFoundException: org.apache.hadoop.hbase.HBaseConfiguration
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1332)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1166)
    at HBaseTest.newFunc(HBaseTest.java:18)
    at BakwasServlet.doGet(BakwasServlet.java:16)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:670)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

This error is frustrating me now. Has anyone encountered such a case before or can anyone help me on this? I don't have hbase_home variable set up. I didn't need it for the java code as well.

Thanks in advance!

Answer 1

Where have you added the HBase JAR file? It should be in the WEB-INF/lib folder of your web application (or in the server's lib folder, but it's better to keep it within the app).