How to Set a System Property

There are various internal settings within Weave that globally alter the way the server functions. These settings can be altered by setting a "system property" which is read when the server starts up.

Occasionally you'll have to set a system property to alter the way the server behaves, to address a support ticket for example, and here we'll describe how that can be done.

Depending upon how you start Weave there are two places where system properties can be set. If you start Weave as a service the properties are set in ...\weave\service\conf\wrapper.conf, and if you start Weave via startup.cmd or startup.sh the properties are set directly in that file.

No matter where the system property is defined, wrapper.conf or startup.cmd/startup.sh, what we will accomplish here is the passing of a new command line parameter to the Weave server process. The command line parameter we're trying to pass to the server process is specified in the format -Dname=value. The -D tells the Java process that we're defining a new property, name is the name of the property we're creating and value is what we want to set it to. As we do not start the Weave server process manually and rely on the service wrapper or startup.cmd/startup.sh to do it for us, what we're outlining here is how we tell them to pass the new command line parameter to the process when it starts.

The setting of a system property, as described here, is only a subset of the things we can do with command line parameters set in the wrapper.conf or startup.cmd/startup.sh, but this How-to page will only cover setting system properties.

Instructions

Setting a system property in wrapper.conf

1. Open ...\weave\service\conf\wrapper.conf in the text editor of your choice.

2. Locate the last additional property in the file (they are usually defined at the end of the file)

   1. The "additional properties" are those listed in the form wrapper.java.additional.## = ...

3. Find the number of the last set additional property, and increase it by one.

4. Create a new additional property, by duplicating an existing one, increment the property number, and set the value to -Dname=value.

   1. Note that it is important that you increment the property number, in the example below we use 22, which is assuming the previous largest property number was 21, but it might be different in your wrapper.conf.

5. Save the file and restart Weave.

Setting the weave.spatial.operation.limit system property to 500

Setting a system property in startup.cmd

1. Open ...\weave\startup.cmd in the text editor of your choice.

2. Locate the last SET JAVA_OPTS line in the file (they are set through the file and the last one would usually be defined near the end of the file).
   
   

   1. The properties are those listed in the form SET JAVA_OPTS=%JAVA_OPTS% -D...=...

   2. There are a number of these lines through the file, that concatenate different system properties into a single JAVA_OPTS variable that is then passed to the Java process at the end of the file.

3. Create a new SET JAVA_OPTS line after the last one with the format:

   1. SET JAVA_OPTS=%JAVA_OPTS% -Dname=value

4. Save the file and restart Weave.

Setting the weave.spatial.operation.limit system property to 500

Setting a system property in startup.sh

1. Open ...\weave\startup.sh in the text editor of your choice.

2. Locate the last JAVA_OPTS="$JAVA_OPTS ..." line in the file (they are set through the file and the last one would usually be defined near the end of the file).

   1. The properties are those listed in the form JAVA_OPTS="$JAVA_OPTS -D...=..."

   2. There are a number of these lines through the file, that concatenate different system properties into a single JAVA_OPTS variable that is then passed to the Java process at the end of the file.

3. Create a new JAVA_OPTS line after the last one with the format:

   1. JAVA_OPTS="$JAVA_OPTS -Dname=value"

4. Save the file and restart Weave.

Setting the weave.spatial.operation.limit system property to 500

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