メモ - JDBCでBLOBの読み書きを行う。

create table blob_test(
  id  char(1) primary key,
  obj blob
);

import java.io.File;
import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;

public class BlobInsert{
    public static void main(String[] args) throws Exception{
        Class.forName("oracle.jdbc.driver.OracleDriver");
        Connection con = DriverManager.getConnection(
                         "jdbc:oracle:thin:@127.0.0.1:1521:sample",
                         "user", 
                         "pass");

        File file = new File("c:\\blob.txt");
        String sql = "insert into blob_test(id, obj)VALUES('1', ?)";
        PreparedStatement stmt = con.prepareStatement(sql);
        stmt.setBinaryStream(1, new FileInputStream(file), (int)file.length());
        int result = stmt.executeUpdate();

        stmt.close();
    }
}

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class BlobRead{
    public static void main(String[] args) throws Exception{
        Class.forName("oracle.jdbc.driver.OracleDriver");
        Connection con = DriverManager.getConnection(
                         "jdbc:oracle:thin:@127.0.0.1:1521:sample", 
                         "user", 
                         "pass");

        Statement state = con.createStatement();
        String sql = "select * from blob_test";
        boolean result = state.execute(sql);
        ResultSet rs = state.getResultSet();
        while(rs.next()) {
            String id = rs.getString(1);
            Blob blob = rs.getBlob(2);
            InputStream in = blob.getBinaryStream();
            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            int bytes;
            byte b[] = new byte[4096];
            while ((bytes = in.read(b)) != -1){
                baos.write(b, 0, bytes);
            }
            System.out.println(id + ":" + baos.toString());
        }
        con.close();
    }
}