Java下使用Oracle存储过程(详解)第1/3页
问题描述：
其实，这篇短文，我早就应该写了。因为，java存储过程今后在各大数据库厂商中越来越流行，功能也越来越强大。这里以Oracle为例，介绍一下java存储过程的具体用法。
答
import java.sql.*;
import oracle.jdbc.*;
public class OracleJavaProc ...{
//Add a salgrade to the database.
public static void addSalGrade(int grade, int losal, int hisal) ...{
System.out.println("Creating new salgrade for EMPLOYEE...");
try ...{
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql =
"INSERT INTO salgrade " +
"(GRADE,LOSAL,HISAL) " +
"VALUES(?,?,?)";
PreparedStatement pstmt = conn.prepareStatement(sql);
pstmt.setInt(1,grade);
pstmt.setInt(2,losal);
pstmt.setInt(3,hisal);
pstmt.executeUpdate();
pstmt.close();
}
catch(SQLException e) ...{
System.err.println("ERROR! Adding Salgrade: "
+ e.getMessage());
}
}
}
使用loadjava命令将其装载到服务器端并编译：
D:eclipse3.1workspacedbtest>loadjava -u scott/tiger@iihero.oracledb -v -resolve Or
acleJavaProc.java
arguments: '-u' 'scott/tiger@iihero.oracledb '-v' '-resolve' 'OracleJavaProc.java'
creating : source OracleJavaProc
loading : source OracleJavaProc
resolving: source OracleJavaProc
查询一下状态：
连接到:
Oracle9i Enterprise Edition Release 9.2.0.1.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.1.0 - Production
SQL> SELECT object_name, object_type, status FROM user_objects WHERE object_type LIKE 'JAVA%';
OBJECT_NAME
--------------------------------------------------------------------------------
OBJECT_TYPE STATUS
------------------------------------ --------------
OracleJavaProc
JAVA CLASS VALID
OracleJavaProc
JAVA SOURCE VALID
测试一下存储过程：
SQL> create or replace procedure add_salgrade(id number, losal number, hisal num
ber) as language java name 'OracleJavaProc.addSalGrade(int, int, int)';
2 /
过程已创建。
SQL> set serveroutput on size 2000
SQL> call dbms_java.set_output(2000);
调用完成。
SQL> execute add_salgrade(6, 10000, 15000);
Creating new salgrade for EMPLOYEE...
PL/SQL 过程已成功完成。
SQL> select * from salgrade where grade=6;
GRADE LOSAL HISAL
---------- ---------- ----------
6 10000 15000
3. 我推荐的一种方法，直接使用loadjava命令远程装载并创建。
先创建一个类, e.g.
复制代码 代码如下:
import java.sql.*;
import oracle.jdbc.*;
public class OracleJavaProc ...{
//Add a salgrade to the database.
public static void addSalGrade(int grade, int losal, int hisal) ...{
System.out.println("Creating new salgrade for EMPLOYEE...");
try ...{
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql =
"INSERT INTO salgrade " +
"(GRADE,LOSAL,HISAL) " +
"VALUES(?,?,?)";
PreparedStatement pstmt = conn.prepareStatement(sql);
pstmt.setInt(1,grade);
pstmt.setInt(2,losal);
pstmt.setInt(3,hisal);
pstmt.executeUpdate();
pstmt.close();
}
catch(SQLException e) ...{
System.err.println("ERROR! Adding Salgrade: "
+ e.getMessage());
}
}
}
使用loadjava命令将其装载到服务器端并编译：
复制代码 代码如下:
D:eclipse3.1workspacedbtest>loadjava -u scott/tiger@iihero.oracledb -v -resolve Or
acleJavaProc.java
arguments: '-u' 'scott/tiger@iihero.oracledb '-v' '-resolve' 'OracleJavaProc.java'
creating : source OracleJavaProc
loading : source OracleJavaProc
resolving: source OracleJavaProc
查询一下状态：
连接到:
Oracle9i Enterprise Edition Release 9.2.0.1.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.1.0 - Production
复制代码 代码如下:
SQL> SELECT object_name, object_type, status FROM user_objects WHERE object_type LIKE 'JAVA%';
OBJECT_NAME
--------------------------------------------------------------------------------
OBJECT_TYPE STATUS
------------------------------------ --------------
OracleJavaProc
JAVA CLASS VALID
OracleJavaProc
JAVA SOURCE VALID
测试一下存储过程：
复制代码 代码如下:
SQL> create or replace procedure add_salgrade(id number, losal number, hisal num
ber) as language java name 'OracleJavaProc.addSalGrade(int, int, int)';
2 /
过程已创建。
SQL> set serveroutput on size 2000
SQL> call dbms_java.set_output(2000);
调用完成。
SQL> execute add_salgrade(6, 10000, 15000);
Creating new salgrade for EMPLOYEE...
PL/SQL 过程已成功完成。
SQL> select * from salgrade where grade=6;
GRADE LOSAL HISAL
---------- ---------- ----------
6 10000 15000
答
import java.sql.*;
import oracle.jdbc.*;
public class OracleJavaProc ...{
// Add a salgrade to the database.
public static void addSalGrade(int grade, int losal, int hisal) ...{
System.out.println("Creating new salgrade for EMPLOYEE...");
try ...{
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql =
"INSERT INTO salgrade " +
"(GRADE,LOSAL,HISAL) " +
"VALUES(?,?,?)";
PreparedStatement pstmt = conn.prepareStatement(sql);
pstmt.setInt(1,grade);
pstmt.setInt(2,losal);
pstmt.setInt(3,hisal);
pstmt.executeUpdate();
pstmt.close();
}
catch(SQLException e) ...{
System.err.println("ERROR! Adding Salgrade: "
+ e.getMessage());
}
}
public static int getHiSal(int grade)
...{
try ...{
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql = "SELECT hisal FROM salgrade WHERE grade = ?";
PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setInt(1, grade);
ResultSet rset = pstmt.executeQuery();
int res = 0;
if (rset.next())
...{
res = rset.getInt(1);
}
rset.close();
return res;
}
catch (SQLException e)
...{
System.err.println("ERROR! Querying Salgrade: "
+ e.getMessage());
return -1;
}
}
}
如何更新呢？
D:eclipse3.1workspacedbtest>dropjava -u scott -v OracleJavaProc
D:/tiger@iihero.oracledbeclipse3.1workspacedbtest>loadjava -u scott -v -resolve Or
acleJavaProc/tiger@iihero.oracledb.java
arguments: '-u' 'scott/tiger@iihero.oracledb' '-v' '-resolve' 'OracleJavaProc.java'
creating : source OracleJavaProc
loading : source OracleJavaProc
resolving: source OracleJavaProc
后边的应用示例：
SQL> create or replace function query_hisal(grade number) return number as langu
age java name 'OracleJavaProc.getHiSal(int) return int';
2 /
函数已创建。
SQL> set serveroutput on size 2000
SQL> call dbms_java.set_output(2000);
调用完成。
SQL> select query_hisal(5) from dual;
QUERY_HISAL(5)
--------------
9999
全文完！
用法个人见解：不要手动drop java source, 不要手动drop procedure。
二、如何更新你已经编写的java存储过程？
假如要往类OracleJavaProc里添加一个存储过程方法，如何开发？
正确的步骤应该是先dropjava, 改程序，再loadjava。
e.g.修改OracleJavaProc类内容如下：
复制代码 代码如下:
import java.sql.*;
import oracle.jdbc.*;
public class OracleJavaProc ...{
// Add a salgrade to the database.
public static void addSalGrade(int grade, int losal, int hisal) ...{
System.out.println("Creating new salgrade for EMPLOYEE...");
try ...{
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql =
"INSERT INTO salgrade " +
"(GRADE,LOSAL,HISAL) " +
"VALUES(?,?,?)";
PreparedStatement pstmt = conn.prepareStatement(sql);
pstmt.setInt(1,grade);
pstmt.setInt(2,losal);
pstmt.setInt(3,hisal);
pstmt.executeUpdate();
pstmt.close();
}
catch(SQLException e) ...{
System.err.println("ERROR! Adding Salgrade: "
+ e.getMessage());
}
}
public static int getHiSal(int grade)
...{
try ...{
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql = "SELECT hisal FROM salgrade WHERE grade = ?";
PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setInt(1, grade);
ResultSet rset = pstmt.executeQuery();
int res = 0;
if (rset.next())
...{
res = rset.getInt(1);
}
rset.close();
return res;
}
catch (SQLException e)
...{
System.err.println("ERROR! Querying Salgrade: "
+ e.getMessage());
return -1;
}
}
}
如何更新呢？
D:eclipse3.1workspacedbtest>dropjava -u scott -v OracleJavaProc
D:/tiger@iihero.oracledbeclipse3.1workspacedbtest>loadjava -u scott -v -resolve Or
acleJavaProc/tiger@iihero.oracledb.java
arguments: '-u' 'scott/tiger@iihero.oracledb' '-v' '-resolve' 'OracleJavaProc.java'
creating : source OracleJavaProc
loading : source OracleJavaProc
resolving: source OracleJavaProc
后边的应用示例：
复制代码 代码如下:
SQL> create or replace function query_hisal(grade number) return number as langu
age java name 'OracleJavaProc.getHiSal(int) return int';
2 /
函数已创建。
SQL> set serveroutput on size 2000
SQL> call dbms_java.set_output(2000);
调用完成。
SQL> select query_hisal(5) from dual;
QUERY_HISAL(5)
--------------
9999
用法个人见解：不要手动drop java source, 不要手动drop procedure。