This topic provides information about accessing DB2CachedRowSet data and various cursor manipulation functions.
RowSets depend on ResultSet methods. For many operations, such as DB2CachedRowSet data access and cursor movement, there is no difference at the application level between using a ResultSet and using a RowSet.
RowSets and ResultSets access data in the same manner. In the following example, the program creates a table and populates it with various data types using JDBC. Once the table is ready, a DB2CachedRowSet is created and populated with the information from the table. The example also uses various get methods of the RowSet class.
Example: Access DB2CachedRowSet data
Note: Read the Code example disclaimer for important legal information.
import java.sql.*;
import javax.sql.*;
import com.ibm.db2.jdbc.app.*;
import java.io.*;
import java.math.*;
public class TestProgram
{
public static void main(String args[])
{
// Register the driver.
try {
Class.forName("com.ibm.db2.jdbc.app.DB2Driver");
}
catch (ClassNotFoundException ex) {
System.out.println("ClassNotFoundException: " +
ex.getMessage());
// No need to go any further.
System.exit(1);
}
try {
Connection conn = DriverManager.getConnection("jdbc:db2:*local");
Statement stmt = conn.createStatement();
// Clean up previous runs
try {
stmt.execute("drop table cujosql.test_table");
}
catch (SQLException ex) {
System.out.println("Caught drop table: " + ex.getMessage());
}
// Create test table
stmt.execute("Create table cujosql.test_table (col1 smallint, col2 int, " +
"col3 bigint, col4 real, col5 float, col6 double, col7 numeric, " +
"col8 decimal, col9 char(10), col10 varchar(10), col11 date, " +
"col12 time, col13 timestamp)");
System.out.println("Table created.");
// Insert some test rows
stmt.execute("insert into cujosql.test_table values (1, 1, 1, 1.5, 1.5, 1.5, 1.5, 1.5, 'one', 'one',
{d '2001-01-01'}, {t '01:01:01'}, {ts '1998-05-26 11:41:12.123456'})");
stmt.execute("insert into cujosql.test_table values (null, null, null, null, null, null, null, null,
null, null, null, null, null)");
System.out.println("Rows inserted");
ResultSet rs = stmt.executeQuery("select * from cujosql.test_table");
System.out.println("Query executed");
// Create a new rowset and populate it...
DB2CachedRowSet crs = new DB2CachedRowSet();
crs.populate(rs);
System.out.println("RowSet populated.");
conn.close();
System.out.println("RowSet is detached...");
System.out.println("Test with getObject");
int count = 0;
while (crs.next()) {
System.out.println("Row " + (++count));
for (int i = 1; i <= 13; i++) {
System.out.println(" Col " + i + " value " + crs.getObject(i));
}
}
System.out.println("Test with getXXX... ");
crs.first();
System.out.println("Row 1");
System.out.println(" Col 1 value " + crs.getShort(1));
System.out.println(" Col 2 value " + crs.getInt(2));
System.out.println(" Col 3 value " + crs.getLong(3));
System.out.println(" Col 4 value " + crs.getFloat(4));
System.out.println(" Col 5 value " + crs.getDouble(5));
System.out.println(" Col 6 value " + crs.getDouble(6));
System.out.println(" Col 7 value " + crs.getBigDecimal(7));
System.out.println(" Col 8 value " + crs.getBigDecimal(8));
System.out.println(" Col 9 value " + crs.getString(9));
System.out.println(" Col 10 value " + crs.getString(10));
System.out.println(" Col 11 value " + crs.getDate(11));
System.out.println(" Col 12 value " + crs.getTime(12));
System.out.println(" Col 13 value " + crs.getTimestamp(13));
crs.next();
System.out.println("Row 2");
System.out.println(" Col 1 value " + crs.getShort(1));
System.out.println(" Col 2 value " + crs.getInt(2));
System.out.println(" Col 3 value " + crs.getLong(3));
System.out.println(" Col 4 value " + crs.getFloat(4));
System.out.println(" Col 5 value " + crs.getDouble(5));
System.out.println(" Col 6 value " + crs.getDouble(6));
System.out.println(" Col 7 value " + crs.getBigDecimal(7));
System.out.println(" Col 8 value " + crs.getBigDecimal(8));
System.out.println(" Col 9 value " + crs.getString(9));
System.out.println(" Col 10 value " + crs.getString(10));
System.out.println(" Col 11 value " + crs.getDate(11));
System.out.println(" Col 12 value " + crs.getTime(12));
System.out.println(" Col 13 value " + crs.getTimestamp(13));
crs.close();
}
catch (Exception ex) {
System.out.println("SQLException: " + ex.getMessage());
ex.printStackTrace();
}
}
}
RowSets are scrollable and act exactly like a scrollable ResultSet. In the following example, the program creates a table and populates it with data using JDBC. Once the table is ready, a DB2CachedRowSet object is created and is populated with the information from the table. The example also uses various cursor manipulation functions.
Example: Cursor manipulation
import java.sql.*;
import javax.sql.*;
import com.ibm.db2.jdbc.app.DB2CachedRowSet;
public class RowSetSample1
{
public static void main(String args[])
{
// Register the driver.
try {
Class.forName("com.ibm.db2.jdbc.app.DB2Driver");
}
catch (ClassNotFoundException ex) {
System.out.println("ClassNotFoundException: " +
ex.getMessage());
// No need to go any further.
System.exit(1);
}
try {
Connection conn = DriverManager.getConnection("jdbc:db2:*local");
Statement stmt = conn.createStatement();
// Clean up previous runs
try {
stmt.execute("drop table cujosql.test_table");
}
catch (SQLException ex) {
System.out.println("Caught drop table: " + ex.getMessage());
}
// Create a test table
stmt.execute("Create table cujosql.test_table (col1 smallint)");
System.out.println("Table created.");
// Insert some test rows
for (int i = 0; i < 10; i++) {
stmt.execute("insert into cujosql.test_table values (" + i + ")");
}
System.out.println("Rows inserted");
ResultSet rs = stmt.executeQuery("select col1 from cujosql.test_table");
System.out.println("Query executed");
// Create a new rowset and populate it...
DB2CachedRowSet crs = new DB2CachedRowSet();
crs.populate(rs);
System.out.println("RowSet populated.");
conn.close();
System.out.println("RowSet is detached...");
System.out.println("Use next()");
while (crs.next()) {
System.out.println("v1 is " + crs.getShort(1));
}
System.out.println("Use previous()");
while (crs.previous()) {
System.out.println("value is " + crs.getShort(1));
}
System.out.println("Use relative()");
crs.next();
crs.relative(9);
System.out.println("value is " + crs.getShort(1));
crs.relative(-9);
System.out.println("value is " + crs.getShort(1));
System.out.println("Use absolute()");
crs.absolute(10);
System.out.println("value is " + crs.getShort(1));
crs.absolute(1);
System.out.println("value is " + crs.getShort(1));
crs.absolute(-10);
System.out.println("value is " + crs.getShort(1));
crs.absolute(-1);
System.out.println("value is " + crs.getShort(1));
System.out.println("Test beforeFirst()");
crs.beforeFirst();
System.out.println("isBeforeFirst is " + crs.isBeforeFirst());
crs.next();
System.out.println("move one... isFirst is " + crs.isFirst());
System.out.println("Test afterLast()");
crs.afterLast();
System.out.println("isAfterLast is " + crs.isAfterLast());
crs.previous();
System.out.println("move one... isLast is " + crs.isLast());
System.out.println("Test getRow()");
crs.absolute(7);
System.out.println("row should be (7) and is " + crs.getRow() +
" value should be (6) and is " + crs.getShort(1));
crs.close();
}
catch (SQLException ex) {
System.out.println("SQLException: " + ex.getMessage());
}
}
}