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The default security policy file {{java.policy}}—found in the /path/to/java.home/lib/security directory on UNIX-like systems and its equivalent on Microsoft Windows systems—grants a few permissions (reading system properties, binding to unprivileged ports, and so forth). Also, a user-specific policy file may be located in the user's home directory. The union of these policy files specifies the permissions granted to a program. The java.security file can specify which policy files are used. If either of the systemwide java.policy or java.security files is deleted, no permissions are granted to the executing Java program.
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