0728_分类管理+标签管理

1.分类管理
（1）添加分类
①编写TypeService类

Page<Type> listType(Pageable pageable);

Type saveType(Type type);

②编写TypeServiceImpl类

@Override
public Page<Type> listType(Pageable pageable){
    return typeRepository.findAll(pageable);
}

@Override
public Type saveType(Type type) {
    return typeRepository.save(type);
}

③编写TypeController类

@PostMapping("/types/add")
public String add(Type type, BindingResult result, RedirectAttributes attributes){
    Type type1 = typeService.getTypeByName(type.getName());
    if(type1!=null){
        result.rejectValue("name","nameError","不能添加重复的分类");
    }
    if(result.hasErrors()){
        return "admin/types-input";
    }
    Type type2 = typeService.saveType(type);
    if(type2==null){
        attributes.addFlashAttribute("message","新增失败");
    }else{
        attributes.addFlashAttribute("message","新增成功");
    }
    return "redirect:/admin/types";
}

④界面展示

（2）删除分类
①编写TypeService类

Type getTypeByName(String name);

void delete(Long id);

②编写TypeServiceImpl类

@Override
public Type getTypeByName(String name) {
    return typeRepository.findByName(name);
}

@Override
public void delete(Long id){
    typeRepository.deleteById(id);
}

③编写TypeController类

@RequestMapping("/types/{id}/delete")
public String delete(@PathVariable Long id,RedirectAttributes attributes){
    typeService.delete(id);
    attributes.addFlashAttribute("message","删除成功");
    return "redirect:/admin/types";
}

④界面展示

（3）更新分类
①编写TypeService类

Type getType(Long id);

Type updateType(Long id,Type type);

②编写TypeServiceImpl类

@Override
public Type getType(Long id) {
    return typeRepository.findById(id).orElse(null);
}

@Override
public Type updateType(Long id, Type type) {
    Type type1 = typeRepository.findById(id).orElse(null);
    if(type1==null){
        System.out.println("未获得更新对象");
        return null;
    }
    BeanUtils.copyProperties(type,type1);
    return typeRepository.save(type1);
}

③编写TypeController类

@RequestMapping("/types/{id}/toUpdate")
public String toUpdate(@PathVariable Long id,Model model){
    System.out.println("id:"+id);
    model.addAttribute("type",typeService.getType(id));
    System.out.println("根据id查得数据为："+typeService.getType(id));
    return "admin/types-input";
}

@RequestMapping("/types/update/{id}")
public String update(@Valid Type type, BindingResult result,@PathVariable Long id, RedirectAttributes attributes){
    System.out.println("传入type:"+type);
    Type type1 = typeService.getTypeByName(type.getName());
    if(type1!=null){
        result.rejectValue("name","nameError","不能添加重复的分类");
    }
    if(result.hasErrors()){
        return "admin/types-input";
    }
    Type type2 = typeService.updateType(id,type);
    if(type2!=null){
        attributes.addFlashAttribute("message","更新成功");

    }
    else {
        attributes.addFlashAttribute("message","更新失败");
    }
    return "redirect:/admin/types";
}

④界面展示

2.标签管理
（1）编写tag实体类

package com.zr0726.myspring.po;

import javax.persistence.*;
import javax.validation.constraints.NotBlank;

@Entity
@Table(name="t_tag")
public class Tag {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @NotBlank(message = "标签名称不能为空")
    private String name;

    public Tag(){

    }
    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;
    }

    @Override
    public String toString() {
        return "Tag{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

（2）编写TagRepository类

package com.zr0726.myspring.dao;

import com.zr0726.myspring.po.Tag;
import org.springframework.data.jpa.repository.JpaRepository;

public interface TagRepository extends JpaRepository<Tag,Long> {

    Tag findByName(String name);

}

（3）编写TagService类

package com.zr0726.myspring.service;

import com.zr0726.myspring.po.Tag;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;

public interface TagService {

    Page<Tag> listTag(Pageable pageable);

    Tag saveTag(Tag tag);

    Tag getTagByName(String name);

    void deleteTag(Long id);

    Tag getTag(Long id);

    Tag updateTag(Long id,Tag tag);

}

（4）编写TagServiceImpl类

package com.zr0726.myspring.service.impl;

import com.zr0726.myspring.dao.TagRepository;
import com.zr0726.myspring.po.Tag;
import com.zr0726.myspring.service.TagService;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;

@Service
public class TagServiceImpl implements TagService {

    @Autowired
    private TagRepository tagRepository;

    @Override
    public Page<Tag> listTag(Pageable pageable) {
        return tagRepository.findAll(pageable);
    }

    @Override
    public Tag saveTag(Tag tag) {
        return tagRepository.save(tag);
    }

    @Override
    public Tag getTagByName(String name) {
        return tagRepository.findByName(name);
    }

    @Override
    public void deleteTag(Long id) {
        tagRepository.deleteById(id);
    }

    @Override
    public Tag getTag(Long id) {
        return tagRepository.findById(id).orElse(null);
    }

    @Override
    public Tag updateTag(Long id, Tag tag) {
        Tag tag1 = tagRepository.findById(id).orElse(null);
        if(tag1==null){
            System.out.println("未获得更新对象");
            return null;
        }
        BeanUtils.copyProperties(tag,tag1);
        return tagRepository.save(tag1);
    }

}

（5）增加标签
①TagService类

Page<Tag> listTag(Pageable pageable);

Tag saveTag(Tag tag);

②TagServiceImpl类

@Override
public Page<Tag> listTag(Pageable pageable) {
    return tagRepository.findAll(pageable);
}

@Override
public Tag saveTag(Tag tag) {
    return tagRepository.save(tag);
}

③TagController类

@PostMapping("/tags/add")
public String add(@Valid Tag tag, BindingResult result, RedirectAttributes attributes){
    Tag tag1 = tagService.getTagByName(tag.getName());
    if(tag1!=null){
        result.rejectValue("name","nameError","不能添加处重复的标签");
        System.out.println(result);
    }
    if(result.hasErrors()){
        return "admin/tags-input";
    }
    Tag tag2 = tagService.saveTag(tag);
    if(tag2==null){
        attributes.addFlashAttribute("message","新增失败");
    }else{
        attributes.addFlashAttribute("message","新增成功");
    }
    return "redirect:/admin/tags";
}

④界面展示

（6）更新标签
①TagService类

Tag getTag(Long id);

Tag updateTag(Long id,Tag tag);

②TagServiceImpl类

@Override
public Tag getTag(Long id) {
    return tagRepository.findById(id).orElse(null);
}

@Override
public Tag updateTag(Long id, Tag tag) {
    Tag tag1 = tagRepository.findById(id).orElse(null);
    if(tag1==null){
        System.out.println("未获得更新对象");
        return null;
    }
    BeanUtils.copyProperties(tag,tag1);
    return tagRepository.save(tag1);
}

③TagController类

@RequestMapping("/tags/{id}/toUpdate")
public String toUpdate(@PathVariable Long id,Model model){
    System.out.println("id:"+id);
    model.addAttribute("tag",tagService.getTag(id));
    System.out.println("根据id查得数据为："+tagService.getTag(id));
    return "admin/tags-input";
}

@RequestMapping("/tags/update/{id}")
public String update(@Valid Tag tag, BindingResult result, @PathVariable Long id, RedirectAttributes attributes){
    System.out.println("传入tag:"+tag);
    Tag tag1 = tagService.getTagByName(tag.getName());
    if(tag1!=null){
        result.rejectValue("name","nameError","不能添加重复的分类");
    }
    if(result.hasErrors()){
        return "admin/tags-input";
    }
    Tag tag2 = tagService.updateTag(id,tag);
    System.out.println("tag2:"+tag2);
    if(tag2!=null){
        attributes.addFlashAttribute("message","更新成功");

    }
    else {
        attributes.addFlashAttribute("message","更新失败");
    }
    return "redirect:/admin/tags";
}

④界面展示