The Wrapper is very flexible and can be set up to work with any directory structure. For this example, we suggest a directory structure which is clean and can be reused even for fairly complicated applications. Please recreate the following directory structure under an arbitrary directory of your choice. We will call this root directory $(EXAMPLE_HOME). This is an extension of the directory structure described in the HelloWorldServer overview.

$(EXAMPLE_HOME)/
$(EXAMPLE_HOME)/bin/
$(EXAMPLE_HOME)/conf/
$(EXAMPLE_HOME)/lang/
$(EXAMPLE_HOME)/lib/
$(EXAMPLE_HOME)/lib/classes/
$(EXAMPLE_HOME)/logs/

Please download the latest version of the Java Service Wrapper for your OS from the Download page, and extract it into a directory of your choice. We will call the extracted directory $(WRAPPER_HOME).

The Java Service Wrapper on UNIX consists of four primary components: the Wrapper binary, a jar file, a native library which is used by the jar file, and a shell script which is used to launch the Wrapper and perform actions such as controlling it as a daemon. Please copy these files as follows:

cp $(WRAPPER_HOME)/bin/wrapper $(EXAMPLE_HOME)/bin/wrapper
cp $(WRAPPER_HOME)/lib/wrapper.jar $(EXAMPLE_HOME)/lib/wrapper.jar
cp $(WRAPPER_HOME)/lib/libwrapper.so $(EXAMPLE_HOME)/lib/libwrapper.so
cp $(WRAPPER_HOME)/src/bin/App.sh.in $(EXAMPLE_HOME)/bin/helloworldserver

After that you need to make the script file executable:

chmod +x helloworldserver

License key:

The Standard and Professional Editions of the Java Service Wrapper require a license key to be able to run. The Wrapper is shipped with a simple license key that will let you run the Wrapper for 15 minutes. Please copy that over for now. You can obtain a long term trial license by clicking on the Free Trial button at the top of the page.

cp $(WRAPPER_HOME)/src/conf/wrapper-license-time.conf $(EXAMPLE_HOME)/conf/wrapper-license.conf

Wrapper configuration file:

Finally, copy over the default Wrapper configuration file. We will edit it in the next section.

cp $(WRAPPER_HOME)/src/conf/wrapper.conf.in $(EXAMPLE_HOME)/conf/wrapper.conf

Open the $(EXAMPLE_HOME)/conf/wrapper.conf file in the text editor of your choice.

Please locate and modify the following properties.

wrapper.java.command=java
wrapper.java.command.loglevel=INFO

wrapper.java.mainclass=org.tanukisoftware.wrapper.WrapperSimpleApp
wrapper.app.parameter.1=HelloWorldServer

wrapper.java.classpath.1=../lib/wrapper.jar
wrapper.java.classpath.2=../lib/classes

wrapper.java.library.path.1=../lib

wrapper.logfile=../logs/wrapper.log

• The wrapper.java.command property is used to specify the location of the Java command that will be used. The value that we have specified will be searched in the system path. It is also possible to specify an absolute path.

• The wrapper.java.command.loglevel property is optional, but it is useful to help debug the Java command line which the Wrapper generates. We recommend that you include this as you get started, but it can be commented out once you have your application working.

• The wrapper.java.mainclass property is used to specify the main class that is passed to Java when it is launched. This is a point of confusion for new users, but in most cases, this will be one of the Wrapper's helper classes rather than the main class of your application. The Wrapper supports several integration methods, but for this example, we are using the most simple method called Integration Method #1 (WrapperSimpleApp).
  This method makes use of the org.tanukisoftware.wrapper.WrapperSimpleApp helper class to manage the JVM lifecycle and backend communication with the Wrapper. For now, don't worry about this point.

• The actual main class of our application HelloWorldServer is passed in as the first parameter using the wrapper.app.parameter.1 property. It is possible to pass in additional parameters to HelloWorldServer by adding additional properties with increasing indexes wrapper.app.parameter.2=P1, for example.

  We don't show them here, but it is also possible to add additional Java parameters using the wrapper.java.additional.<n> properties.

• The next step is to specify the classpath. This is done using the wrapper.java.classpath.<n> properties. We need to have two classpath entries for our application. The first is to include the required wrapper.jar file which includes the Wrapper's helper classes. The second includes the lib/classes directory where our HelloWorldServer class is located.

• The Wrapper makes use of a native library, libwrapper.so, to implement some of its functionality. Native libraries are not used by many Java applications so you may not have encountered them before. The wrapper.java.library.path.<n> properties are used to specify where these libraries are located. For now, don't worry about this point.

• The wrapper.logfile property is used to tell the Wrapper where to write its log file.

We have now told the Wrapper how to run our Java application.

One important thing to note about all of the property values is that they are always specified with path values that are relative to the location of the Wrapper binary.

Open the $(EXAMPLE_HOME)/bin/helloworldserver shell script file in the text editor of your choice.

Somewhere near the beginning of the file you will see two variables: APP_NAME and APP_LONG_NAME. Please replace the values with the name of your application.

# Application
APP_NAME="helloworldserver"
APP_LONG_NAME="Hello World Server"

There are few other variables useful to configure the Wrapper as a daemon, but we will see them a little later in this tutorial.