Check Data Truncation : Data Truncation « Database « Java Tutorial

1. Java Tutorial
2. Database
3. Data Truncation

import java.sql.Connection;
import java.sql.DataTruncation;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLWarning;
import java.sql.Statement;

public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getConnection();
    conn.setAutoCommit(false);
    Statement stmt = conn.createStatement();

    stmt.executeUpdate("create table survey (id int, name CHAR(5) );");

    stmt.executeUpdate("INSERT INTO survey(id, name)VALUES(111, '123456789')");

    displayError(stmt.getWarnings());
    // try to write more data for the name column.
    displayError(stmt.getWarnings());

    // since there were no errors, commit
    conn.commit();

    ResultSet rs = stmt.executeQuery("SELECT * FROM survey");
    outputResultSet(rs);

    rs.close();
    stmt.close();
    conn.close();
  }

  public static void displayError(DataTruncation dataTruncation) {
    if (dataTruncation != null) {
      System.out.println("Data truncation error: ");
      System.out.println(dataTruncation.getDataSize() + " bytes should have been ");
      if (dataTruncation.getRead()) {
        System.out.println("Read (Error:) ");
      } else {
        System.out.println("Written (Error:) ");
      }
      System.out.println(dataTruncation.getTransferSize()
          + " number of bytes of data actually transferred.");
    }
  }

  public static void displayError(SQLWarning warning) {
    while (warning != null) {
      if (warning instanceof DataTruncation) {
        displayError((DataTruncation) warning);
      } else {
        System.out.println(" Warning: " + warning.getMessage());
      }
      warning = warning.getNextWarning();
    }
  }

  private static void outputResultSet(ResultSet rs) throws Exception {
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    for (int i = 1; i < numberOfColumns + 1; i++) {
      String columnName = rsMetaData.getColumnName(i);
      System.out.print(columnName + "   ");

    }
    System.out.println();
    System.out.println("----------------------");

    while (rs.next()) {
      for (int i = 1; i < numberOfColumns + 1; i++) {
        System.out.print(rs.getString(i) + "   ");
      }
      System.out.println();
    }

  }

  private static Connection getConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    String url = "jdbc:hsqldb:mem:data/tutorial";

    return DriverManager.getConnection(url, "sa", "");
  }
}