в 17:43, 31 мая 2010

2010-05-31T17:43:48Z

Admin: 1 версия

2010-05-31T14:47:23Z

1 версия

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== Clob: getCharacterStream() ==



<source lang="java">

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Main {
public static void main(String[] args) throws Exception {
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:ORCL", "yourName", "mypwd");
Statement stmt = conn.createStatement();
createBlobClobTables(stmt);
PreparedStatement pstmt = conn.prepareStatement("INSERT INTO BlobClob VALUES(40,?,?)");
File file = new File("blob.txt");
FileInputStream fis = new FileInputStream(file);
pstmt.setBinaryStream(1, fis, (int) file.length());
file = new File("clob.txt");
fis = new FileInputStream(file);
pstmt.setAsciiStream(2, fis, (int) file.length());
fis.close();
pstmt.execute();
ResultSet rs = stmt.executeQuery("SELECT * FROM BlobClob WHERE id = 40");
rs.next();
java.sql.Blob blob = rs.getBlob(2);
java.sql.Clob clob = rs.getClob(3);
byte blobVal[] = new byte[(int) blob.length()];
InputStream blobIs = blob.getBinaryStream();
blobIs.read(blobVal);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bos.write(blobVal);
blobIs.close();
char clobVal[] = new char[(int) clob.length()];
Reader r = clob.getCharacterStream();
r.read(clobVal);
StringWriter sw = new StringWriter();
sw.write(clobVal);
r.close();
conn.close();
}
public static void createBlobClobTables(Statement stmt) throws Exception {
String Sql = "CREATE TABLE BlobClob(Id NUMBER(3), b BLOB, c CLOB)";
try {
stmt.executeUpdate("DROP TABLE BlobClob");
} catch (SQLException se) {
if (se.getErrorCode() == 942)
System.out.println("Error dropping BlobClob table:" + se.getMessage());
}
if (stmt.executeUpdate(Sql) == 0)
System.out.println("BlobClob table created...");
}
}

</source>



== Clob: getSubString(long pos, int length) ==



<source lang="java">

import java.sql.Clob;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class Main{
public static Connection getConnection() throws Exception {
String driver = "org.gjt.mm.mysql.Driver";
String url = "jdbc:mysql://localhost/databaseName";
String username = "root";
String password = "root";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
public static String getCLOB(int id) throws Exception {
Connection conn = null;
ResultSet rs = null;
PreparedStatement pstmt = null;
String query = "SELECT clobData FROM tableName WHERE id = ?";
try {
conn = getConnection();
pstmt = conn.prepareStatement(query);
pstmt.setInt(1, id);
rs = pstmt.executeQuery();
rs.next();
Clob clob = rs.getClob(1);
// materialize CLOB onto client
String wholeClob = clob.getSubString(1, (int) clob.length());
return wholeClob;
} finally {
rs.close();
pstmt.close();
conn.close();
}
}
public static void main(String args[]) throws Exception {
System.out.println(getCLOB(01));
}
}

</source>

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в 17:43, 31 мая 2010

Admin: 1 версия