Oracle calls Java external stored procedures

1. Write Java

2. Use loadjava to import the database. loadjava is under $ Oracle_HOME/bin.

Loadjava-u <user>/<passwd >@< tns>-resolve-v <java file>

This method loads sourcecode into the database.

If you have previously loaded the same java program, you must first drop

Dropjava-u <user>/<passwd >@< tns>-v <java file>

3. Check that the java database has been imported

Select * from user_source where type LIKE 'java % 'and name =' <JAVA file>'

4. Create a function

Create or replace function <FUNCTION_NAME> (<parameter list in oracle datatype>) RETURN <oracle datatype of return variable>
LANGUAGE JAVA
Name' <clase. method> (<parameter list in java datatype>) return java datatype of return variable ';

Appendix:

If you need java to access files, you must use the dba user to grant permissions.

EXEC Dbms_Java.Grant_Permission ('onboarding ', 'sys: java. lang. runtimepermission', 'writefiledescriptor ','');
EXEC Dbms_Java.Grant_Permission ('onboarding ', 'sys: java. lang. runtimepermission', 'readfiledescriptor ','');
EXEC dbms_java.grant_permission ('onboarding ', 'sys: java. io. filepermission',' <all files> ', 'execute ');

The statement for revoking permissions is as follows:

EXEC Dbms_Java.revoke_Permission ('onboarding ', 'sys: java. lang. runtimepermission', 'writefiledescriptor ','');
EXEC Dbms_Java.revoke_Permission ('onboarding ', 'sys: java. lang. runtimepermission', 'readfiledescriptor ','');
EXEC dbms_java.revoke_permission ('onboarding ', 'sys: java. io. FilePermission', '<all files>', 'execute ');