# Verifying system properties

You can find out the value of a system property if you set it programmatically. You cannot find out the value of a system property if you set it in the derby.properties file.

For example, if you set the value of the `derby.storage.pageSize` system-wide property in your program or on the command line, the following code will retrieve its value from the System Properties object:

    Properties sprops = System.getProperties();
    System.out.println("derby.storage.pageSize value: "
    + sprops.getProperty("derby.storage.pageSize"));

You can also use Java Management Extensions (JMX) technology to obtain system information, including some settings that correspond to system properties. For details, see "Using Java Management Extensions (JMX) technology" in the Derby Server and Administration Guide.

Parent topic: Setting system-wide properties
Related concepts
Changing the system-wide properties programmatically
Changing the system-wide properties by using the derby.properties file