Java Stored Procedures Introduction Benefits of Java Stored Procedures Deployment of Java Stored Procedures (in four steps). Prepared by: Prem Jayaraman Revised by: M V Ramakrishna

Introduction CSE Java Stored Procedure Java stored procedures are Java classes, stored as Oracle schema objects, made accessible to Oracle SQL and PL/SQL through call specifications. The java classes would include SQL statements. Java enables development of database-neutral code. A stored procedure is a program that is stored and executed within database server. The procedure may be called from a Java class, from a PL/SQL programming block etc.

–Starting with Oracle 8i, a fully functional JVM has been integrated into the Oracle database, which enables Java classes to be executed as stored procedures within an Oracle Database Environment –Thus database application developers have the ability to harness the power of Java.

In view of Java's popularity, it is likely that the members of a development team are more proficient in Java than PL/SQL. Java stored procedures enables the database programmers to code in their preferred Java language. Experienced PL/SQL developers, can take advantage of the Java language to extend the functionality of database applications. Thus PL/SQL and Java can coexist in an application CSE Java Stored Procedure Benefits

CSE Java Stored Procedure Java Stored Procedure - Step by Step 1.Writing the Java Class Develop the Java classes using Oracle JDeveloper. Compile, and even unit test your Java code. import java.sql.*; import oracle.jdbc.*; public class EmpManager { //Add an employee to the database. public static void addEmp(int emp_id, String emp_f_name, String emp_l_name,float emp_salary, int dept_id) { System.out.println("Creating new employee..."); try { Connection conn = DriverManager.getConnection("jdbc:default:connection:"); String sql = "INSERT INTO empVALUES(" + emp_id + "," + "'" + emp_f_name + "'," + "'" + emp_l_name + "'," + emp_salary + "," + dept_id + ")"; PreparedStatement pstmt = conn.prepareStatement(sql); pstmt.executeUpdate(); pstmt.close(); } catch(SQLException e) { System.err.println("ERROR! Adding Employee: " + e.getMessage()); }

CSE Java Stored Procedure Java Stored Procedure - Step by Step 2.Loading the Java Class Load the Java Class into the Oracle Database using JDeveloper Use the LoadJava and Java Stored Procedure option in the deployment profile.

CSE Java Stored Procedure Java Stored Procedure - Step by Step 3.Publishing the Java Stored Procedure Any class that will be directly called from SQL or PL/SQL must be published A Java class is published by creating and compiling a call specification for it. The call specification, often referred to as a call spec or even a PL/SQL wrapper, maps a Java method's parameters and return type to Oracle SQL types. These operations are performed by JDeveloper

CSE Java Stored Procedure Java Stored Procedure - Step by Step 4. Calling the Procedures We have developed, loaded and published the Java class as a Java Stored Procedure. Now we test the same by executing the procedure in SQL * PLUS The DBMS_JAVA package, an Oracle-supplied package with utilities for managing server-side Java has a method for redirecting output to SQL*Plus SQL> SET SERVEROUTPUT ON SQL> CALL dbms_java.set_output(2000); Now, Java output will displayed upon execution. SQL> EXECUTE add_emp(1,'Joe', 'Smith', ,1); Creating new employee... PL/SQL procedure successfully completed.