用反射技术去除Switch或者if，解除简单工厂类的判断语句带来的耦合。
用配置文件全项目替代数据库类型实现Oracle、Mysql，或者加入SqlServer等数据库实现。
优点：比抽象工厂减少耦合（Ifactory,MysqlFactory,OracleFactory变为一个ReflectSqlFactory，而且切换数据库只需要改配置文件）
比简单工厂减少耦合（采用反射技术，减少switch或if 语句）
sql.properties
db=Mysql
ReflectSqlFactory类
package reflectAbstractFactory;
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.Iterator;
import java.util.Properties;
import reflectAbstractFactory.dept.IDeptDao;
import reflectAbstractFactory.user.IUserDao;
public class ReflectSqlFactory {
public String getDb() {
Properties prop = new Properties();
String db = "";
try {
// 读取属性文件a.properties
InputStream in = new BufferedInputStream(new FileInputStream(
"E:/workspace/dahuasheji/sampleFactory/src/reflectAbstractFactory/sql.properties"));
prop.load(in); // /加载属性列表
Iterator<String> it = prop.stringPropertyNames().iterator();
while (it.hasNext()) {
String key = it.next();
if("db".endsWith(key)){
db = prop.getProperty("db");
break;
}
}
in.close();
} catch (Exception e) {
System.out.println(e);
}
return db;
}
public Class<?> getsqlFactory(String pge,String type) throws ClassNotFoundException{
String className= "reflectAbstractFactory."+pge+getDb()+type+"Dao";
System.out.println(className);
Class<?> c1 = Class.forName(className);
System.out.println(c1.getName());
return c1;
}
public IUserDao createUser() throws InstantiationException, IllegalAccessException, ClassNotFoundException{
Class<?> c = getsqlFactory("user.","User");
IUserDao iu = (IUserDao)c.newInstance();
return iu;
};
public IDeptDao createDept() throws ClassNotFoundException, InstantiationException, IllegalAccessException{
Class<?> c = getsqlFactory("dept.","Dept");
IDeptDao id = (IDeptDao)c.newInstance();
return id;
};
}
Business类
package reflectAbstractFactory;
import reflectAbstractFactory.dept.Department;
import reflectAbstractFactory.dept.IDeptDao;
import reflectAbstractFactory.user.IUserDao;
import reflectAbstractFactory.user.User;
public class Business {
public static void main(String[] args) throws InstantiationException, IllegalAccessException, ClassNotFoundException {
//产品1系列
User user = new User();
ReflectSqlFactory reflectSqlFactory = new ReflectSqlFactory();
IUserDao iuDao = reflectSqlFactory.createUser();
iuDao.insert(user);
iuDao.getUser(1);
//产品2系列
Department dept = new Department();
IDeptDao idepatDao = reflectSqlFactory.createDept();
idepatDao.insert(dept);
idepatDao.getDept(1);
}
}
Department类
package reflectAbstractFactory.dept;
public class Department {
private long id;
private String deptName;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getDeptName() {
return deptName;
}
public void setDeptName(String deptName) {
this.deptName = deptName;
}
}
IDeptDao类
package reflectAbstractFactory.dept;
public interface IDeptDao {
void insert(Department dept);
void getDept(int id);
}
MysqlDeptDao类
package reflectAbstractFactory.dept;
public class MysqlDeptDao implements IDeptDao {
@Override
public void insert(Department dept) {
System.out.println("在mysql数据库的department表插入一条记录");
}
@Override
public void getDept(int id) {
System.out.println("在mysql数据库的department表根据ID获取一条记录");
}
}
OracleDeptDao类
package reflectAbstractFactory.dept;
public class OracleDeptDao implements IDeptDao {
@Override
public void insert(Department dept) {
System.out.println("在oracle数据库的department表插入一条记录");
}
@Override
public void getDept(int id) {
System.out.println("在oracle数据库的department表根据ID获取一条记录");
}
}
IUserDao类
package reflectAbstractFactory.user;
public interface IUserDao {
void insert(User user);
void getUser(int id);
}
MysqlUserDao类
package reflectAbstractFactory.user;
public class MysqlUserDao implements IUserDao {
@Override
public void insert(User user) {
System.out.println("在mysql数据库的user表插入一条记录");
}
@Override
public void getUser(int id) {
System.out.println("在mysql数据库的user表根据ID获取一条记录");
}
}
OracleUserDao类
package reflectAbstractFactory.user;
public class OracleUserDao implements IUserDao {
@Override
public void insert(User user) {
System.out.println("在oracle数据库的user表插入一条记录");
}
@Override
public void getUser(int id) {
System.out.println("在oracle数据库的user表根据ID获取一条记录");
}
}
User类
package reflectAbstractFactory.user;
public class User {
private long id;
private String name;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
package reflectAbstractFactory;
import java.io.BufferedInputStream;import java.io.FileInputStream;import java.io.InputStream;import java.util.Iterator;import java.util.Properties;
import reflectAbstractFactory.dept.IDeptDao;import reflectAbstractFactory.user.IUserDao;
public class ReflectSqlFactory {public String getDb() {Properties prop = new Properties();String db = "";try {// 读取属性文件a.propertiesInputStream in = new BufferedInputStream(new FileInputStream("E:/workspace/dahuasheji/sampleFactory/src/reflectAbstractFactory/sql.properties"));prop.load(in); // /加载属性列表Iterator<String> it = prop.stringPropertyNames().iterator();while (it.hasNext()) {String key = it.next();if("db".endsWith(key)){db = prop.getProperty("db");break;}}in.close();} catch (Exception e) {System.out.println(e);}return db;}public Class<?> getsqlFactory(String pge,String type) throws ClassNotFoundException{String className= "reflectAbstractFactory."+pge+getDb()+type+"Dao";System.out.println(className);Class<?> c1 = Class.forName(className);System.out.println(c1.getName());return c1;}public IUserDao createUser() throws InstantiationException, IllegalAccessException, ClassNotFoundException{Class<?> c = getsqlFactory("user.","User");IUserDao iu = (IUserDao)c.newInstance();return iu;};public IDeptDao createDept() throws ClassNotFoundException, InstantiationException, IllegalAccessException{Class<?> c = getsqlFactory("dept.","Dept");IDeptDao id = (IDeptDao)c.newInstance();return id;};}