Java/Database SQL JDBC/CachedRowSet

Cached RS

 
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import javax.sql.rowset.CachedRowSet;
public class CachedRS {
  private final static String CRS_FILE_LOC = "cachedrs.crs";
  public static void main(String[] args) throws Exception {
    FileInputStream fis = new FileInputStream(CRS_FILE_LOC);
    ObjectInputStream in = new ObjectInputStream(fis);
    CachedRowSet crs = (CachedRowSet) in.readObject();
    fis.close();
    in.close();
    
    Class.forName("oracle.jdbc.driver.OracleDriver");
    crs.setUrl("jdbc:oracle:thin:@localhost:1521:ORCL");
    crs.setUsername("yourName");
    crs.setPassword("mypwd");
    String sql = "SELECT SSN, Name, Salary, Hiredate FROM Employees WHERE SSN=?";
    crs.setCommand(sql);
    crs.setInt(1, 111111111);
    crs.execute();
    FileOutputStream fos = new FileOutputStream(CRS_FILE_LOC);
    ObjectOutputStream out = new ObjectOutputStream(fos);
    out.writeObject(crs);
    out.close();
    crs.close();
    
    fis = new FileInputStream(CRS_FILE_LOC);
    in = new ObjectInputStream(fis);
    crs = (CachedRowSet) in.readObject();
    fis.close();
    in.close();
    while (crs.next()) {
      System.out.print("SSN: " + crs.getInt("ssn"));
      System.out.print(", Name: " + crs.getString("name"));
      System.out.print(", Salary: $" + crs.getDouble("salary"));
      System.out.print(", HireDate: " + crs.getDate("hiredate"));
    }
    crs.close();
  }
}

Save CachedRowSet Back To Database

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.sql.Types;
import javax.sql.RowSetMetaData;
import javax.sql.rowset.CachedRowSet;
import javax.sql.rowset.RowSetMetaDataImpl;
import com.sun.rowset.CachedRowSetImpl;
public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getHSQLConnection();
    System.out.println("Got Connection.");
    Statement st = conn.createStatement();
    st.executeUpdate("create table survey (id int,name varchar);");
    st.executeUpdate("create view surveyView as (select * from survey);");
    st.executeUpdate("insert into survey (id,name ) values (1,"nameValue")");
    st.executeUpdate("insert into survey (id,name ) values (2,"anotherValue")");    
    
    CachedRowSet crs = null;
    RowSetMetaData rsMD = new RowSetMetaDataImpl();
    rsMD.setColumnCount(2);
    rsMD.setColumnName(1, "id");
    rsMD.setColumnType(1, Types.VARCHAR);
    rsMD.setColumnName(2, "name");
    rsMD.setColumnType(2, Types.VARCHAR);
    // sets the designated column"s table name, if any, to the given String.
    rsMD.setTableName(1, "survey");
    rsMD.setTableName(2, "survey");
    // use a custom made RowSetMetaData object for CachedRowSet object
    crs = new CachedRowSetImpl();
    crs.setMetaData(rsMD);
    crs.moveToInsertRow();
    crs.updateString(1, "1111");
    crs.updateString(2, "alex");
    crs.insertRow();
    crs.moveToInsertRow();
    crs.updateString(1, "2222");
    crs.updateString(2, "jane");
    crs.insertRow();
    // if you want to commit changes from a CachedRowSet
    // object to your desired datasource, then you must
    // create a Connection object.
    //
    //conn = getHSQLConnection();
    // moves the cursor to the remembered cursor position, usually
    // the current row. This method has no effect if the cursor is
    // not on the insert row.
    crs.moveToCurrentRow();
    // when the method acceptChanges() is executed, the CachedRowSet
    // object"s writer, a RowSetWriterImpl object, is called behind the
    // scenes to write the changes made to the rowset to the underlying
    // data source. The writer is implemented to make a connection to
    // the data source and write updates to it.
    crs.acceptChanges(conn);
    conn.close();
  }
  private static Connection getHSQLConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    System.out.println("Driver Loaded.");
    String url = "jdbc:hsqldb:data/tutorial";
    return DriverManager.getConnection(url, "sa", "");
  }
  public static Connection getMySqlConnection() throws Exception {
    String driver = "org.gjt.mm.mysql.Driver";
    String url = "jdbc:mysql://localhost/demo2s";
    String username = "oost";
    String password = "oost";
    Class.forName(driver);
    Connection conn = DriverManager.getConnection(url, username, password);
    return conn;
  }
  public static Connection getOracleConnection() throws Exception {
    String driver = "oracle.jdbc.driver.OracleDriver";
    String url = "jdbc:oracle:thin:@localhost:1521:caspian";
    String username = "mp";
    String password = "mp2";
    Class.forName(driver); // load Oracle driver
    Connection conn = DriverManager.getConnection(url, username, password);
    return conn;
  }
}