Example to retrieve file from Oracle database

The getClob() method of PreparedStatement is used to get file information from the database.

Syntax of getClob method

1. public Clob getClob(int columnIndex){}  

Let's see the table structure of this example to retrieve the file.

1. CREATE TABLE  "FILETABLE"   
2.    (    "ID" NUMBER,   
3.     "NAME" CLOB  
4.    )  
5. /  

The example to retrieve the file from the Oracle database is given below.

1. import java.io.*;  
2. import java.sql.*;  
3.   
4. public class RetrieveFile {  
5. public static void main(String[] args) {  
6. try{  
7. Class.forName("oracle.jdbc.driver.OracleDriver");  
8. Connection con=DriverManager.getConnection(  
9. "jdbc:oracle:thin:@localhost:1521:xe","system","oracle");  
10.               
11. PreparedStatement ps=con.prepareStatement("select * from filetable");  
12. ResultSet rs=ps.executeQuery();  
13. rs.next();//now on 1st row  
14.               
15. Clob c=rs.getClob(2);  
16. Reader r=c.getCharacterStream();              
17.               
18. FileWriter fw=new FileWriter("d:\\retrivefile.txt");  
19.               
20. int i;  
21. while((i=r.read())!=-1)  
22. fw.write((char)i);  
23.               
24. fw.close();  
25. con.close();  
26.               
27. System.out.println("success");  
28. }catch (Exception e) {e.printStackTrace();  }  
29. }  
30. }