package com.hq.servlet.core;
import com.alibaba.fastjson.JSON;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
* @author zth
* @Date 2019-04-21 19:37
*/
public abstract class Action extends HttpServlet {
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
req.setCharacterEncoding("utf-8");
// 防止浏览器缓存
resp.setHeader("Pragma", "No-cache");
resp.setHeader("Cache-Control", "no-cache");
resp.setDateHeader("Expires", 0);
String method = null!= req.getParameter("action")?req.getParameter("action"):"index";
Class<? extends Action> clazz = this.getClass();
// 访问一个带 Mapping 参数的方法
try {
Method meth = clazz.getDeclaredMethod(method,Mapping.class);
if (null != meth){
meth.invoke(this,new Mapping(req,resp));
}
} catch (Exception e) {
e.printStackTrace();
System.out.println("ERROR_1000_找不到目标方法！" + e.getMessage());
req.getRequestDispatcher("error/error404.jsp").forward(req,resp);
}
}
// 默认要实现的方法
public abstract void index(Mapping mapping) throws ServletException,IOException;
/**
* 封装内部类，因为成员内部类在多线程可能会出现问题
*/
public class Mapping {
private HttpServletRequest req;
private HttpServletResponse resp;
public Mapping(HttpServletRequest req, HttpServletResponse resp) {
this.req = req;
this.resp = resp;
}
protected SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
// 获取字符串
public String getString(String param){
return null!= req.getParameter(param)?req.getParameter(param):"";
}
// 获取字符数组
public String[] getStringArray(String param){
return req.getParameterValues(param);
}
// 获取数字
public int getInt(String param){
int re = 0;
String str = this.getString(param);
if (str.matches("\\d+")){
re = Integer.parseInt(str);
}
return re;
}
public int[] getIntArray(String param){
int[] re = null;
String[] strs = this.getStringArray(param);
if (null != strs && strs.length > 0){
re = new int[strs.length];
for (int i = 0; i < strs.length; i++) {
if (null != strs[i] && strs[i].matches("\\d+")){
re[i] = Integer.parseInt(strs[i]);
}else {
re[i]= 0;
}
}
}
return re;
}
public Long getLong (String param){
long re = 0;
String str = this.getString(param);
if (str.matches("\\d+")){
re = Long.parseLong(str);
}
return re;
}
public BigDecimal getBigDecimal (String param){
BigDecimal re = null;
String str = this.getString(param);
re = new BigDecimal(str);
return re;
}
// 填充请求参数到 Bean 对象
public void getBean(Object bean){
Class<? extends Object> clazz = bean.getClass();
Field[] fields = clazz.getDeclaredFields();
if (null!=fields && fields.length>0){
try {
for (Field field:fields) {
field.setAccessible(true);
String fname = field.getName();
Class<?> type = field.getType();
String paramv = this.getString(fname);
if (type == String.class){
field.set(bean,paramv);
}else if (type == Integer.class || type == int.class || type == Integer.TYPE){
field.set(bean,this.getInt(fname));
}else if (type == Long.class || type == long.class || type == Long.TYPE){
field.set(bean,this.getInt(fname));
}else if (type == BigDecimal.class){
field.set(bean,this.getBigDecimal(fname));
}else if (type == Date.class){
if (paramv.matches("\\d{4}[-]\\d{2}[-]\\d{2}[ ]\\d{2}[:]\\d{2}[:]\\d{2}")){
field.set(bean,simpleDateFormat.parse(paramv));
}
}
}
}catch (Exception e){
e.printStackTrace();
System.out.println("ERROR_002_填充对象值出错");
}
}
}
// 对 request 的访问
public Object getAttr(String key){
return req.getAttribute(key);
}
public void setAttr(String key,Object value){
req.setAttribute(key,value);
}
public void forward(String path) throws ServletException, IOException {
req.getRequestDispatcher("/WEB-INF/"+path).forward(req,resp);
}
public void redirect(String path) throws IOException {
resp.sendRedirect(path);
}
// 直接输出值
public void randerText(String msg) throws IOException {
resp.setContentType("text/html;charset=utf-8");
PrintWriter out = resp.getWriter();
out.println(msg);
out.close();
}
// 输出 json
public void randerJson(Object object) throws IOException {
resp.setContentType("text/html;charset=utf-8");
PrintWriter out = resp.getWriter();
out.println(JSON.toJSONString(object));
out.close();
}
// 从 session 中获取值
public Object getSessionAttr(String param){
return req.getSession().getAttribute(param);
}
// 设置 session 值
public void setSessionAttr(String key,Object val){
req.getSession().setAttribute(key,val);
}
// 删除 session 中的值
public void removeSessionAttr(String key){
req.getSession().removeAttribute(key);
}
// 销毁 session
public void invalidateSession(){
req.getSession().invalidate();
}
public String basePath(){
return req.getScheme()+"://"+req.getServerName()+":"+req.getServerPort()+req.getContextPath()+"/";
}
public HttpServletRequest getReq() {
return req;
}
public void setReq(HttpServletRequest req) {
this.req = req;
}
public HttpServletResponse getResp() {
return resp;
}
public void setResp(HttpServletResponse resp) {
this.resp = resp;
}
}
}
