Compiling and Packaging a Java Library

Before you can use your Java UDx, you need to compile it and package it into a JAR file.

The SDK examples include a working makefile. See Downloading and Running UDx Example Code.

Compile Your Java UDx

You must include the SDK JAR file in the classpath when you compile your Java UDx source files so the Java compiler can resolve the Vertica API calls. If you are using the command-line Java compiler on a host in your database cluster, enter this command:

$ javac -classpath /opt/vertica/bin/VerticaSDK.jar factorySource.java \
      [functionSource.java...] -d output-directory

If all of your source files are in the same directory, you can use *.java on the command line instead of listing the files individually.

If you are using an IDE, verify that a copy of the VerticaSDK.jar file is in the build path.

UDx Class File Organization

After you compile your UDx, you must package its class files and the BuildInfo.class file into a JAR file.

To use the jar command packaged as part of the JDK, you must organize your UDx class files into a directory structure matching your class package structure. For example, suppose your UDx's factory class has a fully-qualified name of com.mycompany.udfs.Add2ints. In this case, your class files must be in the directory hierarchy com/mycompany/udfs relative to your project's base directory. In addition, you must have a copy of the BuildInfo.class file in the path com/vertica/sdk so that it can be included in the JAR file. This class must appear in your JAR file to indicate the SDK version that was used to compile your Java UDx.

The JAR file for the Add2ints UDSF example explained in Java Example: Add2Ints has the following directory structure after compilation:

com/vertica/sdk/BuildInfo.class
com/mycompany/example/Add2intsFactory.class
com/mycompany/example/Add2intsFactory$Add2ints.class

Package Your UDx Into a JAR File

To create a JAR file from the command line:

1. Change to the root directory of your project.

2. Use the jar command to package the BuildInfo.class file and all of the classes in your UDx:

   # jar -cvf libname.jar com/vertica/sdk/BuildInfo.class \
          packagePath/*.class
   

   When you type this command, libname is the filename you have chosen for your JAR file (choose whatever name you like), and packagePath is the path to the directory containing your UDx's class files.

   • For example, to package the files from the Add2ints example, you use the command:

     # jar -cvf Add2intsLib.jar com/vertica/sdk/BuildInfo.class \
     com/mycompany/example/*.class

   • More simply, if you compiled BuildInfo.class and your class files into the same root directory, you can use the following command:

     # jar -cvf Add2intsLib.jar .

   You must include all of the class files that make up your UDx in your JAR file. Your UDx always consists of at least two classes (the factory class and the function class). Even if you defined your function class as an inner class of your factory class, Java generates a separate class file for the inner class.

After you package your UDx into a JAR file, you are ready to deploy it to your Vertica database.