java oracle clob string 大字符串存储【转】

单位用到了oracle存储string类型到数据库里的clob，上网查看资料找到解决方案。如下：

 1     public class ClobTest {
 2
 3         static String url = "jdbc:oracle:thin:@10.12.10.18:1521:orcl";
 4         static String user = "cwbe1_9999";
 5         static String pwd = "or777";
 6         static String text = "这是要插入到CLOB里面的数据,更新数据！" + "update";
 7
 8         private static int clobImport() throws ClassNotFoundException, SQLException {
 9             DriverManager.registerDriver(new OracleDriver());
10             Connection conn = DriverManager.getConnection(url, user, pwd);// 得到连接对象
11             String sql = "insert into ETLNEEDPARAM(F_KEY,F_VALUE) values (‘defaultpo‘,?)";// 要执行的SQL语句
12             PreparedStatement stmt = conn.prepareStatement(sql);// 加载SQL语句
13             // PreparedStatement支持SQL带有问号？，可以动态替换？的内容。
14             Reader clobReader = new StringReader(text); // 将 text转成流形式
15             stmt.setCharacterStream(1, clobReader, text.length());// 替换sql语句中的？
16             int num = stmt.executeUpdate();// 执行SQL
17             if (num > 0) {
18                 System.out.println("ok");
19             } else {
20                 System.out.println("NO");
21             }
22             stmt.close();
23             conn.close();
24             return num;
25         }
26
27         private static int clobUpdate(String key) throws ClassNotFoundException, SQLException {
28
29             DriverManager.registerDriver(new OracleDriver());
30             Connection conn = DriverManager.getConnection(url, user, pwd);// 得到连接对象
31             String sql = "update ETLNEEDPARAM set F_VALUE = ? where F_KEY = ? ";// 要执行的SQL语句
32             PreparedStatement stmt = conn.prepareStatement(sql);// 加载SQL语句
33             // PreparedStatement支持SQL带有问号？，可以动态替换？的内容。
34             Reader clobReader = new StringReader(text); // 将 text转成流形式
35             stmt.setString(2, key);
36             stmt.setCharacterStream(1, clobReader, text.length());// 替换sql语句中的？
37             int num = stmt.executeUpdate();// 执行SQL
38             if (num > 0) {
39                 System.out.println("ok");
40             } else {
41                 System.out.println("NO");
42             }
43             stmt.close();
44             conn.close();
45             return num;
46         }
47
48         private static String clobExport() throws ClassNotFoundException, SQLException, IOException {
49
50             CLOB clob = null;
51             String sql = "select F_VALUE from ETLNEEDPARAM where F_KEY =‘test1‘";
52             DriverManager.registerDriver(new OracleDriver());
53             Connection conn = DriverManager.getConnection(url, user, pwd);// 得到连接对象
54             PreparedStatement stmt = conn.prepareStatement(sql);
55             ResultSet rs = stmt.executeQuery();
56             String content = "";
57             if (rs.next()) {
58                 clob = (oracle.sql.CLOB) rs.getClob("F_VALUE"); // 获得CLOB字段str
59                 // 注释： 用 rs.getString("str")无法得到 数据 ，返回的 是 NULL;
60                 content = ClobToString(clob);
61             }
62             stmt.close();
63             conn.close();
64             return content;
65         }
66
67         // 将字CLOB转成STRING类型
68
69         public static String ClobToString(CLOB clob) throws SQLException, IOException {
70             String reString = "";
71             Reader is = clob.getCharacterStream();// 得到流
72             BufferedReader br = new BufferedReader(is);
73             String s = br.readLine();
74             StringBuffer sb = new StringBuffer();
75             // 执行循环将字符串全部取出付值给StringBuffer由StringBuffer转成STRING
76             while (s != null) {
77                 sb.append(s);
78                 s = br.readLine();
79             }
80             reString = sb.toString();
81             return reString;
82         }
83
84         public static void main(String[] args) throws IOException,ClassNotFoundException, SQLException {
85             // System.out.println(clobImport());
86             System.out.println(clobUpdate("fmo"));
87             System.out.println(clobUpdate("epo"));
88
89             // System.out.println(clobExport());
90
91         }  

转自：http://bestxiaok.iteye.com/blog/1027733