Java反射机制
package com.utils;
import java.beans.Introspector;
import
java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import
java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import
java.util.Date;
import java.util.Enumeration;
import
javax.servlet.http.HttpServletRequest;
public class ReflectUtil {
//方法1
public static <T> T initlize(Class<T> clazz, HttpServletRequest
request)
throws Exception {
T t = clazz.newInstance();
Field[]
fields = clazz.getDeclaredFields();// 变量的对象
for (Field field : fields)
{
String filedName = field.getName();// 变量对象的名字
Class<?>
fieldType = field.getType();// 变量的数据类型
Enumeration<String> enumeration
= request.getParameterNames();// 获取表单文本的的对象
while
(enumeration.hasMoreElements()) {
String pName =
enumeration.nextElement();// 获取表单文本对象的名称
if (filedName.equals(pName))
{
String preflexStr = filedName.substring(0, 1);
String
sufflexStr = filedName.substring(1);
String writeMethodStr = "set" +
preflexStr.toUpperCase()
+ sufflexStr;// 方法名
Method writeMethod =
clazz.getDeclaredMethod(
writeMethodStr, new Class<?>[] {
fieldType });// 造方法
String pValue = request.getParameter(pName);
if
(fieldType.toString().equals("int")) {
writeMethod.invoke(t,
Integer.valueOf(pValue)
.intValue());
continue;
}
else if (fieldType.newInstance() instanceof Date) {
SimpleDateFormat
simpleDateFormat = new SimpleDateFormat(
"yyyy-MM-dd");
Date
date = simpleDateFormat.parse(pValue);
System.out.println("********" +
pValue);
System.out.println("+++++++++" +
date);
writeMethod.invoke(t, date);
continue;
} else
if (fieldType.newInstance() instanceof Integer) {
writeMethod.invoke(t,
Integer.valueOf(pValue)
.intValue());
continue;
}
writeMethod.invoke(t,
pValue);
}
}
}
return t;
}
//方法2
public static <T> T initlize01(Class<T> clazz,
HttpServletRequest request)
throws Exception {
T t =
clazz.newInstance();
PropertyDescriptor[] propertyDscriptors =
Introspector.getBeanInfo(
clazz).getPropertyDescriptors();
for
(PropertyDescriptor propertyDescriptor : propertyDscriptors) {
String
fileName = propertyDescriptor.getName();
Method writeMothod =
propertyDescriptor.getWriteMethod();
if (writeMothod != null)
{
Enumeration<String> enumeration =
request.getParameterNames();
while (enumeration.hasMoreElements())
{
String pName = enumeration.nextElement();
if
(fileName.equals(pName)) {
String pValue =
request.getParameter(pName);
writeMothod.invoke(t,
pValue);
}
}
}
}
return t;
}
}
通过反射避免重复代码，将表单获取的值直接传到实体类中