databaseutilities.java

来自「用java编写的数据库管理程序」· Java 代码 · 共 118 行

package createdb;

import java.awt.event.*;
import java.sql.*;
import java.util.Vector;
import sun.jdbc.odbc.JdbcOdbcDriver;

public class DatabaseUtilities{
  static String jdbcDriver = "sun.jdbc.odbc.JdbcOdbcDriver";
  static String dbName = "Contacts";
  static String urlRoot = "jdbc:odbc:";
  private ActionListener exceptionListener = null;

  public DatabaseUtilities(){
    registerDriver();
  }
  public void setDatabaseName(String dbName){
    this.dbName=dbName;
  }
  public void registerDriver(){
    try {
      Class.forName(jdbcDriver);
      DriverManager.registerDriver(new JdbcOdbcDriver());
    }
    catch(ClassNotFoundException e){
      reportException(e.getMessage());
    }
    catch(SQLException e){
      reportException(e.getMessage());
    }
  }
  public void execute(String SQLCommand){
    String url = urlRoot+dbName;
    try {
      Connection con = DriverManager.getConnection(url);
      Statement stmt = con.createStatement();

      stmt.execute(SQLCommand);
      con.close();
    }
    catch(SQLException e){
      reportException(e.getMessage());
    }
  }
  public void execute(String[] SQLCommand){
    String url = urlRoot+dbName;
    try {
      Connection con = DriverManager.getConnection(url);
      Statement stmt = con.createStatement();
      for(int i=0;i<SQLCommand.length;i++){

        stmt.execute(SQLCommand[i]);
      }
      con.close();
    }
    catch(SQLException e){
      reportException(e.getMessage());
    }
  }
  public String[] getColumnNames(String tableName){
    Vector dataSet = new Vector();
    String[] columnNames = null;
    String url = urlRoot+dbName;
    String SQLCommand = "SELECT * FROM "+tableName+";";

    try {
      Connection con = DriverManager.getConnection(url);
      Statement stmt = con.createStatement();
      ResultSet rs = stmt.executeQuery(SQLCommand);
      ResultSetMetaData md = rs.getMetaData();

      columnNames = new String[md.getColumnCount()];
      for(int i=0;i<columnNames.length;i++){
        columnNames[i] = md.getColumnLabel(i+1);
      }
      con.close();
    }
    catch(SQLException e){
      reportException(e.getMessage());
    }
    return columnNames;
  }
  public String[] getDataTypes(String tableName){
    Vector dataSet = new Vector();
    String[] dataTypes = null;
    String url = urlRoot+dbName;
    String SQLCommand = "SELECT * FROM "+tableName+";";

    try {
      Connection con = DriverManager.getConnection(url);
      Statement stmt = con.createStatement();
      ResultSet rs = stmt.executeQuery(SQLCommand);
      ResultSetMetaData md = rs.getMetaData();

      dataTypes = new String[md.getColumnCount()];
      for(int i=0;i<dataTypes.length;i++){
        dataTypes[i] = md.getColumnTypeName(i+1);
      }
      con.close();
    }
    catch(SQLException e){
      reportException(e.getMessage());
    }
    return dataTypes;
  }
  public void setExceptionListener(ActionListener exceptionListener){
    this.exceptionListener=exceptionListener;
  }
  private void reportException(String exception){
    if(exceptionListener!=null){
      ActionEvent evt = new ActionEvent(this,0,exception);
      exceptionListener.actionPerformed(evt);
    }else{
      System.err.println(exception);
    }
  }
}