java Class Method類的使用

package sample;

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * 
 * @author heavens
 */
public class ExecuteSqlUtil {

    private Class clsDBAccess;
    private Object objClass;

    /**
     * 調用默認構造方法，不帶參數
     * 
     * @param classname
     *            調用的類名
     */
    public ExecuteSqlUtil(String classname) {
        try {
            clsDBAccess = Class.forName(classname);
            objClass = clsDBAccess.newInstance();
        } catch (InstantiationException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (IllegalAccessException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (ClassNotFoundException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        }
    }

    /**
     * 調用帶有參數的構造方法
     * 
     * @param classname
     *            調用類名
     * @param parameterTypes
     *            參數類型組
     * @param parameterValues
     *            參數值組
     */
    public ExecuteSqlUtil(String classname, Class[] parameterTypes,
            Object[] parameterValues) {
        try {
            clsDBAccess = Class.forName(classname);
            Constructor cs = clsDBAccess.getDeclaredConstructor(parameterTypes);// 構造方法
            objClass = cs.newInstance(parameterValues);
        } catch (InstantiationException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (IllegalAccessException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (IllegalArgumentException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (InvocationTargetException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (NoSuchMethodException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (SecurityException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (ClassNotFoundException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        }
    }

    /**
     * 對update方法的封裝
     * 
     * @param sql
     * @return
     */
    public boolean updateSql(String sql) {
        boolean flag = false;
        try {
            Class[] types = new Class[1];
            types[0] = String.class;
            Method mtd = clsDBAccess.getMethod("update", types);
            mtd.invoke(objClass, sql);
            Method mtd2 = clsDBAccess.getMethod("close");
            mtd2.invoke(objClass);
            flag = true;
        } catch (IllegalArgumentException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (InvocationTargetException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (NoSuchMethodException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (SecurityException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (IllegalAccessException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        }
        return flag;
    }

    /**
     * 對query方法的封裝
     * 
     * @param sql
     * @return
     */
    public ResultSet querySql(String sql) {
        ResultSet rs = null;
        try {
            Class[] types = new Class[1];
            types[0] = String.class;
            Method mtd = clsDBAccess.getMethod("query", types);
            rs = (ResultSet) mtd.invoke(objClass, sql);
        } catch (IllegalArgumentException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (InvocationTargetException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (IllegalAccessException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (NoSuchMethodException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (SecurityException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        }
        return rs;
    }

    /**
     * 關閉數據庫鏈接
     * 
     * @return
     */
    public boolean closeConnection() {
        boolean flag = false;
        try {
            Method mtd = clsDBAccess.getMethod("close");
            mtd.invoke(objClass);
            flag = true;
        } catch (IllegalArgumentException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (InvocationTargetException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (NoSuchMethodException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (SecurityException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        } catch (IllegalAccessException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        }
        return flag;
    }

    public static void main(String argv[]) {
        try {
            ExecuteSqlUtil mysql = new ExecuteSqlUtil(
                    "ConnPoolLcl.DatabaseAccess",
                    new Class[] { boolean.class }, new Object[] { true });
            ResultSet rs = mysql.querySql("select * from user");
            while (rs.next()) {
                System.out
                        .println(rs.getString(1) + "======" + rs.getString(2));
            }
            System.exit(0);
        } catch (SQLException ex) {
            Logger.getLogger(ExecuteSqlUtil.class.getName()).log(Level.SEVERE,
                    null, ex);
        }
    }
}