The Java Plug-in Control Panel consists of the following elements:
Apply button - Saves any changes you make in the Control Panel.
Reset button - Restores default values.
If you make changes in the Control Panel, you must restart Netscape Navigator for the changes to take effect.
The Basic tab controls the basic operations of Java Plug-in and includes the following options:
Show Java Console -- Displays the Java Console while running applets or JavaBeans components. The console displays messages printed by the System.out and System.err objects, and is useful for debugging problems. The default setting is selected.
Cache JARs in Memory -- Caches (reuses) previously-loaded applets or component classes, allowing for more efficient memory use. Uncheck this option when debugging an applet or component, or if you want to ensure that the latest applets or component classes are downloaded. The default setting is selected.
Network Access -- With Java Plug-in, applets run under the standard JDK applet security manager, which prevents untrusted applets from performing potentially dangerous operations such as reading local files. Refer to the Java Security FAQ and Using Signed Applets with Java Plug-in for more details.
None -- Grants no access to the network.
Applet Host -- Restricts an applet's network access so that the applet cannot make any network calls (default setting).
Unrestricted -- Grants an applet unrestricted access to the network, so the applet can connect to any host server.
It is a security hazard to grant unrestricted network access to applets.
Java Runtime Parameters -- Enables you to enter custom options that override the Java Plug-in default startup parameters. The syntax is the same as the parameters to the java command-line invocation. For more information, type man java at the command line to view the Java man page.
Refer to the JDK 1.2 documentation for information on specifying the command-line parameters when invoking the java command.
You use the Advanced tab to specify the Java Runtime Environment (JRE) used by Java Plug-in. The Control Panel automatically detects all versions of the JDKs and JREs installed on your machine, and displays these in the dropdown list box.
Sun does not support the use of any JRE less than 1.2.1_03 with Java Plug-in 1.2.
If you use a JRE other than the default, you must specify the JRE path using an environment variable.
Proxy configuration is an essential part of setting up a secure computing environment. A proxy server acts as a security barrier, making it impossible for an outsider to access your intranet, while allowing your intranet users to access the Internet. The Proxies tab controls the addresses and port numbers that Java Plug-in uses when communicating through a proxy server.
You can set the following proxy configurations from the Proxies tab:
Use browser settings -- Uses Navigator's default proxy settings. Netscape Navigator stores proxy information in a file on the local machine. Java Plug-in reads this file to obtain the proxy information at startup. The default setting is selected.
Proxy Settings -- Overrides Navigator's default proxy settings. Enter the Proxy Address and Port for the protocols you want to use.
Same proxy server for all protocols -- If you are using the same address and port for all protocols, enter the Proxy Address and Port once and select this check box.
The Certificates tab lists the Netscape Object Signing Certificates trusted by Java Plug-in. Java Plug-in uses the standard JDK key and certificate management resources from the identity.obj file, controlled by the javakey utility.