gjarsigner - Java ARchive (JAR) file signing and verification tool


   jarsigner [OPTION]... FILE ALIAS

   jarsigner -verify [OPTION]... FILE


   When the first form is used, the tool signs the designated JAR file.
   The second form, on the other hand, is used to verify a previously
   signed JAR file.

   FILE is the .JAR file to process; i.e., to sign if the first syntax
   form is used, or to verify if the second syntax form is used instead.

   ALIAS must be a known Alias of a Key Entry in the designated Key Store.
   The private key material associated with this Alias is then used for
   signing the designated .JAR file.


   Common options

   The following options may be used when the tool is used for either
   signing, or verifying, a .JAR file.

       Use this option to force the tool to generate more verbose
       messages, during its processing.

       When present, the tool will include --which otherwise it does not--
       the ".SF" file in the ".DSA" generated file.

       When present, the tool will include in the ".SF" generated file
       --which otherwise it does not-- a header containing a hash of the
       whole manifest file.  When that header is included, the tool can
       quickly check, during verification, if the hash (in the header)
       matches or not the manifest file.

       A fully qualified class name of a Security Provider to add to the
       current list of Security Providers already installed in the JVM in-
       use. If a provider class is specified with this option, and was
       successfully added to the runtime --i.e. it was not already
       installed-- then the tool will attempt to remove this Security
       Provider before exiting.

       Prints a help text similar to this one.

   Signing options

   The following options may be specified when using the tool for signing

   -keystore URL
       Use this option to specify the location of the key store to use.
       The default value is a file URL referencing the file named
       .keystore located in the path returned by the call to
       "java.lang.System#getProperty(String)" using "user.home" as

       If a URL was specified, but was found to be malformed --e.g.
       missing protocol element-- the tool will attempt to use the URL
       value as a file-name (with absolute or relative path-name) of a key
       store --as if the protocol was "file:".

   -storetype STORE_TYPE
       Use this option to specify the type of the key store to use. The
       default value, if this option is omitted, is that of the property
       "keystore.type" in the security properties file, which is obtained
       by invoking the static method call "getDefaultType()" in

   -storepass PASSWORD
       Use this option to specify the password which will be used to
       unlock the key store. If this option is missing, the User will be
       prompted to provide a password.

   -keypass PASSWORD
       Use this option to specify the password which the tool will use to
       unlock the Key Entry associated with the designated Alias.

       If this option is omitted, the tool will first attempt to unlock
       the Key Entry using the same password protecting the key store. If
       this fails, you will then be prompted to provide a password.

   -sigfile NAME
       Use this option to designate a literal that will be used to
       construct file names for both the ".SF" and ".DSA" signature files.
       These files  will be generated, by the tool, and placed in the
       META-INF directory of the signed JAR.  Permissible characters for
       NAME must be in the range "a-zA-Z0-9_-".  All characters will be
       converted to upper-case ones.

       If this option is missing, the first eight characters of the ALIAS
       argument will be used. When this is the case, any character in
       ALIAS that is outside the permissible range of characters will be
       replaced by an underscore.

   -signedjar FILE
       Use this option to specify the file name of the signed JAR. If this
       option is omitted, then the signed JAR will be named the same as
       FILE; i.e., the input JAR file will be replaced with the signed

   Verification options

   The following options may be specified when using the tool for
   verification purposes.

       Use this option to indicate that the tool is to be used for
       verification purposes.

       This option is used in conjunction with the -verbose option. When
       present, along with the -verbose option, the tool will print more
       detailed information about the certificates of the signer(s) being






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