Java 存储和读取 oracle CLOB 类型字段
- package oracle.clob;
- import java.io.BufferedReader;
- import java.io.File;
- import java.io.FileReader;
- import java.io.IOException;
- import java.io.Reader;
- import java.io.StringReader;
- import java.sql.Connection;
- import java.sql.DriverManager;
- import java.sql.PreparedStatement;
- import java.sql.ResultSet;
- import java.sql.SQLException;
- import oracle.jdbc.driver.OracleDriver;
- import oracle.sql.CLOB;
- public class ClobTest {
- String url = "jdbc:oracle:thin:@192.168.2.157:1521:orcl";
- String user = "xj";
- String pwd = "xj";
- String text = "这是要插入到CLOB里面的数据";
- private void clobImport() throws ClassNotFoundException, SQLException {
- // TODO Auto-generated method stub
- DriverManager.registerDriver(new OracleDriver());
- Connection conn = DriverManager.getConnection(url, user, pwd);// 得到连接对象
- String sql = "insert into clob_test(id,str) values ('1',?)";// 要执行的SQL语句
- PreparedStatement stmt = conn.prepareStatement(sql);// 加载SQL语句
- // PreparedStatement支持SQL带有问号?,可以动态替换?的内容。
- Reader clobReader = new StringReader(text); // 将 text转成流形式
- stmt.setCharacterStream(1, clobReader, text.length());// 替换sql语句中的?
- int num = stmt.executeUpdate();// 执行SQL
- if (num > 0) {
- System.out.println("ok");
- } else {
- System.out.println("NO");
- }
- stmt.close();
- conn.close();
- }
- private void clobExport() throws ClassNotFoundException, SQLException,
- IOException {
- // TODO Auto-generated method stub
- CLOB clob = null;
- String sql = "select * from clob_test where id=1";
- DriverManager.registerDriver(new OracleDriver());
- Connection conn = DriverManager.getConnection(url, user, pwd);// 得到连接对象
- PreparedStatement stmt = conn.prepareStatement(sql);
- ResultSet rs = stmt.executeQuery();
- String id = "";
- String content = "";
- if (rs.next()) {
- id = rs.getString("id");// 获得ID
- clob = (oracle.sql.CLOB) rs.getClob("str"); // 获得CLOB字段str
- // 注释: 用 rs.getString("str")无法得到 数据 ,返回的 是 NULL;
- content = ClobToString(clob);
- }
- stmt.close();
- conn.close();
- // 输出结果
- System.out.println(id);
- System.out.println(content);
- }
- // 将字CLOB转成STRING类型
- public String ClobToString(CLOB clob) throws SQLException, IOException {
- String reString = "";
- Reader is = clob.getCharacterStream();// 得到流
- BufferedReader br = new BufferedReader(is);
- String s = br.readLine();
- StringBuffer sb = new StringBuffer();
- while (s != null) {// 执行循环将字符串全部取出付值给StringBuffer由StringBuffer转成STRING
- sb.append(s);
- s = br.readLine();
- }
- reString = sb.toString();
- return reString;
- }
- // TODO Auto-generated method stub
- public static void main(String[] args) throws IOException,
- ClassNotFoundException, SQLException {
- // TODO Auto-generated method stub
- ClobTest clobtest = new ClobTest();
- // read file
- FileReader _frd = new FileReader(new File("D://DOS.txt"));
- BufferedReader _brd = new BufferedReader(_frd);
- String _rs = _brd.readLine();
- StringBuffer _input = new StringBuffer();
- while (_rs != null) {
- _input.append(_rs);
- _rs = _brd.readLine();
- }
- // System.out.println(_input.toString());
- // 输入测试
- clobtest.text = _input.toString();
- clobtest.clobImport();
- // 输出测试
- // clobtest.clobExport();
- }
- }