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The default policy file java.policy grants a few permissions (reading system properties, binding to unprivileged ports and so forth) and can be found in the ~/java.home/lib/security directory on Unix-like systems and its equivalent on Microsoft Windows systems. There is also a user specific policy file in the user's home directory. The union of both these policy files defines the permissions given to a program. Refer to the java.security file to set which policy files should be used. If either of these is deleted, by default no permissions are granted to the implementing code.
If the default policy file needs to be bypassed in lieu of a custom policy file, a double equals (==) idiom should be used.
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