CMS系统学习笔记（三）

一、工作（jobs）的CRUD

• 1.三层架构

  dao层

package cn.itsource.cms.dao;

import java.util.List;

import cn.itsource.cms.domain.Jobs;
import cn.itsource.cms.page.PageList;
import cn.itsource.cms.query.SqlCondition;

public interface IJobsDao {
	void save(Jobs jobs);
	void update(Jobs jobs);
	void delete(Integer id);
	Jobs finalId(Integer id);
	List finalAll();
	//分页查询的方法，query代表的是有条件查询
	PageList queryAll(SqlCondition condition);
}

impl

package cn.itsource.cms.dao.impl;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import cn.itsource.cms.dao.IJobsDao;
import cn.itsource.cms.domain.Jobs;
import cn.itsource.cms.page.PageList;
import cn.itsource.cms.query.SqlCondition;
@Repository
public class JobsDaoImpl implements IJobsDao{
	@Autowired
	private JdbcTemplate jdbc;

	
	@Override
	public void save(Jobs jobs) {
		
		jdbc.update("insert into t_jobs (title,address_id,jobnum,treatment,describes,requires,htmlurl,positiontype,isenabled,inputdate) "
				+ "values(?,?,?,?,?,?,?,?,?,?);",jobs.getTitle(),jobs.getAddress_id(),jobs.getJobnum(),jobs.getTreatment(),jobs.getDescribes(),jobs.getRequires()
				,jobs.getHtmlurl(),jobs.getPositiontype(),jobs.getIsenabled(),jobs.getInputdate()
				);
	}

	@Override
	public void update(Jobs jobs) {
		//修改要求：只修改简介和是否启用
		jdbc.update("update t_jobs  set title=?,address_id=?,jobnum=?,treatment=?,describes=?,requires=?,htmlurl=?,positiontype=?,isenabled=?,inputdate=? where id=?;",
				jobs.getTitle(),jobs.getAddress_id(),jobs.getJobnum(),jobs.getTreatment(),jobs.getDescribes(),jobs.getRequires()
				,jobs.getHtmlurl(),jobs.getPositiontype(),jobs.getIsenabled(),jobs.getInputdate(),jobs.getId()	);
	}

	@Override
	public void delete(Integer id) {
		jdbc.update("delete from t_jobs  where id=?;",id);
	}

	@Override
	public Jobs finalId(Integer id) {
		try {

			return jdbc.queryForObject("select * from t_jobs  where id =?", new BeanPropertyRowMapper(Jobs.class),id);
		} catch (Exception e) {
			// TODO: handle exception
			return null;
		}
	}

	@Override
	public List finalAll() {
		try {

			return jdbc.query("select * from v_jobs ;", new BeanPropertyRowMapper(Jobs.class));
		} catch (Exception e) {
			return null;
		}
	}

	@Override
	public PageList queryAll(SqlCondition condition) {
		//拿到当前页和每页条数
		int currentPage = condition.getCurrentPage();
		int pageSize = condition.getPageSize();
		//获取当前查询的sql
		String whereSql = condition.createWhereSql();
		//查询总条数
		//1.准备查询总条数的sql语句
		String sql="select count(*) from v_jobs "+whereSql;
		//执行语句,拿到总条数
		Integer totalCount = jdbc.queryForObject(sql, Integer.class);
		//查询当前页的数据
		//1.计算当前也是从第几条数据开始的
		int beginIndex = (currentPage-1) * pageSize;
		//sql语句
		String datasql ="select * from v_jobs "+whereSql+" limit "+beginIndex+","+pageSize;
		//执行查询功能
		List data = jdbc.query(datasql, new BeanPropertyRowMapper(Jobs.class));
		//创建Pagelist，并返回
		PageList pageList = new PageList<>(currentPage, pageSize, totalCount, data);
		return pageList;
	}

}

service

package cn.itsource.cms.service;

import java.util.List;

import cn.itsource.cms.domain.Jobs;
import cn.itsource.cms.page.PageList;
import cn.itsource.cms.query.SqlCondition;

public interface IJobsService {
	void save(Jobs jobs);
	void update(Jobs jobs);
	void delete(Integer id);
	Jobs finalId(Integer id);
	List finalAll();
	//分页查询的方法，query代表的是有条件查询
	PageList queryAll(SqlCondition condition);
}

domain

package cn.itsource.cms.domain;

import java.util.Date;

public class Jobs {
	private Integer id;
	private String title;//职位标题
	private String address;//招聘地址
	//工作地址对应的id
	private Integer address_id;
	private Integer jobnum;//招聘人数
	private Integer treatment;//待遇（工资）
	private String describes;//职位描述
	private String requires;//职业要求
	private String htmlurl;//静态网站地址
	private Integer positiontype;//职位类型
	private Boolean isenabled;//是否录入
	private Date inputdate = new Date();//录入时间
	/**
	 * @return the id
	 */
	public Integer getId() {
		return id;
	}
	/**
	 * @param id the id to set
	 */
	public void setId(Integer id) {
		this.id = id;
	}
	/**
	 * @return the title
	 */
	public String getTitle() {
		return title;
	}
	/**
	 * @param title the title to set
	 */
	public void setTitle(String title) {
		this.title = title;
	}
	/**
	 * @return the address
	 */
	public String getAddress() {
		return address;
	}
	/**
	 * @param address the address to set
	 */
	public void setAddress(String address) {
		this.address = address;
	}
	/**
	 * @return the jobnum
	 */
	public Integer getJobnum() {
		return jobnum;
	}
	/**
	 * @param jobnum the jobnum to set
	 */
	public void setJobnum(Integer jobnum) {
		this.jobnum = jobnum;
	}
	/**
	 * @return the treatment
	 */
	public Integer getTreatment() {
		return treatment;
	}
	/**
	 * @param treatment the treatment to set
	 */
	public void setTreatment(Integer treatment) {
		this.treatment = treatment;
	}
	/**
	 * @return the describes
	 */
	public String getDescribes() {
		return describes;
	}
	/**
	 * @param describes the describes to set
	 */
	public void setDescribes(String describes) {
		this.describes = describes;
	}
	/**
	 * @return the requires
	 */
	public String getRequires() {
		return requires;
	}
	/**
	 * @param requires the requires to set
	 */
	public void setRequires(String requires) {
		this.requires = requires;
	}
	/**
	 * @return the htmlurl
	 */
	public String getHtmlurl() {
		return htmlurl;
	}
	/**
	 * @param htmlurl the htmlurl to set
	 */
	public void setHtmlurl(String htmlurl) {
		this.htmlurl = htmlurl;
	}
	/**
	 * @return the positiontype
	 */
	public Integer getPositiontype() {
		return positiontype;
	}
	/**
	 * @param positiontype the positiontype to set
	 */
	public void setPositiontype(Integer positiontype) {
		this.positiontype = positiontype;
	}
	/**
	 * @return the isenabled
	 */
	public Boolean getIsenabled() {
		return isenabled;
	}
	/**
	 * @param isenabled the isenabled to set
	 */
	public void setIsenabled(Boolean isenabled) {
		this.isenabled = isenabled;
	}
	/**
	 * @return the inputdate
	 */
	public Date getInputdate() {
		return inputdate;
	}
	/**
	 * @param inputdate the inputdate to set
	 */
	public void setInputdate(Date inputdate) {
		this.inputdate = inputdate;
	}
	
	/**
	 * @return the address_id
	 */
	public Integer getAddress_id() {
		return address_id;
	}
	/**
	 * @param address_id the address_id to set
	 */
	public void setAddress_id(Integer address_id) {
		this.address_id = address_id;
	}
	/* (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		return id + ", " + title + ", " + address + ", " + jobnum + ", " + treatment + ", " + describes + ", "
				+ requires + ", " + htmlurl + ", " + positiontype + ", " + isenabled + ", " + inputdate + "]";
	}
	

}

Controller

package cn.itsource.cms.web.controller;

import java.io.File;
import java.io.FileWriter;
import java.util.HashMap;
import java.util.UUID;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;

import com.sun.org.apache.xalan.internal.xsltc.compiler.sym;

import cn.itsource.cms.domain.Jobs;
import cn.itsource.cms.query.SqlCondition;
import cn.itsource.cms.service.IAddressService;
import cn.itsource.cms.service.IJobsService;
import freemarker.template.Configuration;
import freemarker.template.Template;

@Controller
@RequestMapping("/jobs")
public class JobsController {
	@Autowired
	private IJobsService jobsService;
	@Autowired
	private IAddressService addressService;
	@RequestMapping("/query")
	public String query(SqlCondition condition, Model model){
		//把所有数据传到前台(支持分页的)
		model.addAttribute("pageList", jobsService.queryAll(condition));
		return "jobs";
	}

	/**修改或添加的跳转
	 * @return
	 */
	@RequestMapping("/input")
	public String input(Integer id,Model model){
		model.addAttribute("addressList",addressService.fandll());
		if (id != null) {
			//把当前的工作对象传到前端
			model.addAttribute("job", jobsService.finalId(id));
			return "jobs_edit";//ID不为空，就携带当前的工作对象传递到前台，跳转到修改界面
		}
		return "jobs_add";//没有ID就跳转到添加页面
	}

	@RequestMapping("/save")
	public String save(Jobs jobs,HttpServletRequest req) throws Exception{
		//如果这个静态页面已经存在，我就要把它干掉，避免创建多个静态页面
		String realPath = req.getServletContext().getRealPath("/statichtml");
		String htmlurl = jobs.getHtmlurl();//获取静态网站地址
		if (htmlurl != null) {
			File file2 = new File(realPath, htmlurl);
			// 判断这个文件是否存在
			if (file2.exists()) {
				System.gc();//召唤垃圾回收
				file2.delete();
			}
			
		}
		
		//拿到配置对象
		Configuration configuration = new Configuration(Configuration.VERSION_2_3_28); 
		//加载路径
		String path  = "F:/c/javaee/cmstest/src/main/webapp/statichtml";
		configuration.setDirectoryForTemplateLoading(new File(path));
		//设置字符集
		configuration.setDefaultEncoding("utf-8");
		//获取模板
		Template template = configuration.getTemplate("details.ftl");
		//准备数据（数据就是jobs）
		HashMap map = new HashMap<>();
		map.put("job", jobs);
		//确保HTML名称唯一性,准备一个html的名称
		String uuid = UUID.randomUUID().toString()+".html";
		File file = new File(path, uuid);
		FileWriter fileWriter = new FileWriter(file);
		//把数据和模板输出,数据+模板=输出
		template.process(map, fileWriter);
		fileWriter.close();
		//把相应的名称放到jobs中去
		jobs.setHtmlurl(uuid);
		if (jobs.getId() !=null) {
			jobsService.update(jobs);
		}else{
			jobsService.save(jobs);
		}
		return "redirect:/jobs/query";
	}

	@RequestMapping("/delete/{id}")
	public String delete(@PathVariable("id") Integer id,HttpServletRequest req){
	//拿到相应的地址
		String realPath = req.getServletContext().getRealPath("//statichtml");
		Jobs jobs = jobsService.finalId(id);
		String htmlurl = jobs.getHtmlurl();
		//创建相应的文件
		File file = new File(realPath, htmlurl);
		if (file.exists()) {
			System.gc();
			file.delete();
			
		}
		jobsService.delete(id);
		return "redirect:/jobs/query";
	}

}

• • 注意：以后开发要注意，一个domain的属性(一张表中的列)在开发的时候一定要先把它搞清楚

二、回显功能

			
				
						selected
					
				>${address.name}
			
		

三、创建视图

• • 视图：相当于是一个假表
• 视图本质就是对查询的一个封装
• • 视图创建：create view 视图名称 as select…
• create view stuscore as select students.*,scores.score from scores inner join students on scores.stuid=students.id;
• • 视图查询：select * from 视图名称

五、模板技术

• • 动态网页(数据可变)与静态网页(访问快，SEO排名高)
    - 动态网页静态化(伪静态[只改后缀]，真静态)
    用到模板技术：数据+模板=输入文本
    freemarker【ftl】,velocity【vm】

• -查错方法：

• F12->看js有没有错，再看网络传参有没有问题
  如果前端没有问题,问题就在后端(有没有接收参数，如果接收到了，有没有调用方法,SQL有没有写对，数据有没有返回)
  没有找到 -> 比较法,打印法,删除法