The dropjava Tool

12.7 The dropjava Tool

The dropjava tool is the converse of the loadjava tool. It transforms command-line file names and JAR or ZIP file contents to schema object names, drops the schema objects, and deletes their corresponding digest table rows. You can enter .java, .class, .zip, .jar, and resource file names on the command line and in any order.

Alternatively, you can specify a schema object name directly to the dropjava tool. A command-line argument that does not end in .jar, .zip, .class, .java is presumed to be a schema object name. If you specify a schema object name that applies to multiple schema objects, then all will be removed.

Dropping a class invalidates classes that depend on it, recursively cascading upwards. Dropping a source drops classes derived from it.

Note:

If you load a JAR using the -jarsasdbobjects (-prependjarnames) option, then you must specify the -prependjarnames argument to successfully remove the JAR.

You can run the dropjava tool either from the command line or by using the dropjava method in the DBMS_JAVA class. To run the dropjava tool from within your Java application, use the following command:

call dbms_java.dropjava('... options...');

The options are the same as specified on the command line. Separate each option with a space. Do not separate the options using commas. The only exception to this is the -resolver option. The connection is always made to the current session. Therefore, you cannot specify another user name through the -user option.

For -resolver, you should specify all other options first, a comma (,), then the -resolver option with its definition. Do not specify the -thin, -oci, -user, and -password options, because they relate to the database connection for the loadjava tool. The output is directed to stderr. Set serveroutput on and call dbms_java.set_output, as appropriate.

This section covers the following topics:

12.7.1 dropjava Tool Syntax

The syntax of the dropjava tool command is:

dropjava [options] {file.java | file.class | 
file.jar | file.zip | resourcefile} ...
  -u | -user user/[password][@database]
  [-genmissingjar JARfile]
  [-jarasresource]
  [-module module-name]
  [-automatic]

  [-o | -oci | -oci8]
  [-optionfile file]
  [-optiontable table_name]
  [-S | -schema schema]
  [-stdout]
  [-s | -synonym]
  [-t | -thin]

  [-v | -verbose]
  [-jarsasdbobjects]
  [-prependjarnames]
  [-list]
[-listfile]

12.7.2 dropjava Tool Argument Summary

Table 12-3 summarizes the dropjava tool arguments.

Table 12-3 dropjava Argument Summary

Argument	Description
`-user`	Specifies a user name, password, and optional database connection string. The files will be dropped from this database instance.
`automatic`	Drops a JAR file that was loaded with the `-automatic` option.
`-module <name>`	Drops the classes from a named module. This option is generally not required, except in the circumstances where the `-module` option was required by `loadjava`.
`filenames`	Specifies any number and combination of `.java`, `.class`, `.jar`, `.zip`, and resource file names.
`-genmissingjar` `JARfile`	Treats the operand of this option as a file to be processed.
`-jarasresource`	Drops the whole JAR file, which was previously loaded as a resource.
`-jarsasdbobjects`	Drop the JAR files that were loaded with the `-jarsasdbobjects` option.
`-oci \| -oci8`	Directs the `dropjava` tool to connect with the database using the OCI JDBC driver. The `-oci` and the `-thin` options are mutually exclusive. If neither is specified, then the `-oci` option is used by default. Choosing the `-oci` option implies the form of the `-user` value.
`-optionfile` `file`	Has the same usage as for the `loadjava` tool.
`-optiontable` `table_name`	Has the same usage as for `loadjava`.
`-prependjarnames`	Drops the JAR files that were loaded with the `-prependjarnames` option.
`-schema` `schema`	Designates the schema from which schema objects are dropped. If not specified, then the logon schema is used. To drop a schema object from a schema that is not your own, you need the `DROP ANY PROCEDURE` and `UPDATE ANY TABLE` privileges.
`-stdout`	Causes the output to be directed to `stdout`, rather than to `stderr`.
`-synonym`	Drops a `PUBLIC` synonym that was created with the `loadjava` tool.
`-thin`	Directs the `dropjava` tool to communicate with the database using the JDBC Thin driver. Choosing the `-thin` option implies the form of the `-user` value.
`-verbose`	Directs the `dropjava` tool to emit detailed status messages while running.
`–list`	Drops the classes, Java source, or resources listed on the command line without them being present on the client machine or server machine.
`-listfile`	Reads a file and drops the classes, Java source, or resources listed in the file without them being present on the client machine or the server machine. The file contains the internal representation of the complete class, Java source, or resource name one per line.

12.7.3 dropjava Tool Argument Details

This section describes a few of the dropjava tool arguments, which are complex.

File Names

The dropjava tool interprets most file names as the loadjava tool does:

.class files

Finds the class name in the file and drops the corresponding schema object.
.java files

Finds the first class name in the file and drops the corresponding schema object.
.jar and .zip files

Processes the archived file names as if they had been entered on the command line.

If a file name has another extension or no extension, then the dropjava tool interprets the file name as a schema object name and drops all source, class, and resource objects that match the name.

If the dropjava tool encounters a file name that does not match a schema object, then it displays a message and processes the remaining file names.

user

{-user | -u} user/password[@database]

The permissible forms of @database depend on whether you specify -oci or -thin:

-oci:@database is optional. If you do not specify, then the dropjava tool uses the user's default database. If specified, then database can be a TNS name or an Oracle Net Services name-value list.
-thin:@database is required. The format is host:lport:SID.

where:
- host is the name of the computer running the database.
- lport is the listener port that has been configured to listen for Oracle Net Services connections. In a default installation, it is 5521.
- SID is the database instance identifier. In a default installation, it is ORCL.

The following are examples of the dropjava tool command:

Drop all schema objects in the TEST schema in the default database that were loaded from ServerObjects.jar:
```
dropjava -u HR -schema TEST ServerObjects.jar
Password: password
```
Connect with the JDBC Thin driver, then drop a class and a resource file from the user's schema:
```
dropjava -thin -u HR@dbhost:5521:orcl alpha.class beta.props
Password: password
```

List Based Deletion

Earlier versions of the dropjava tool required that the classes, JARs, source, and resources be present on the machine, where the client or server side utility is running. The current version of dropjava has an option that enables you to drop classes, resources, or sources based on a list of classes, which may not exist on the client machine or the server machine. This list can be either on the command line or in a text file. For example:

dropjava –list –u HR –v this.is.my.class this.is.your.class
Password: password

The preceding command drops the classes this.is.my.class and this.is.your.class listed on the command line without them being present on the client machine or server machine.

dropjava –listfile my.list –u HR –s –v
Password: password

The preceding command drops classes, resources, or sources and their synonyms based on a list of classes listed in my.list and displays verbosely.

Note:

The '-install' flag ignores the loading and dropping of system owned schema objects that cannot be modified.

These schema objects are the runtime classes, and resources provided by the CREATE JAVA COMMAND.

12.7.4 About Dropping Resources Using dropjava Tool

You must be careful if you are removing a resource that was loaded directly into the server. The fully qualified schema object name of a resource that was generated on the client and loaded directly into the server, depends on path information in the .jar file or that specified on the command line at the time you loaded it. If you use a .jar file to load resources and use the same .jar file to remove resources, then there are no problems. However, if you use the command line to load resources, then you must be careful to specify the same path information when you run the dropjava tool to remove the resources.