SSM横向拓展一个功能--->搜索

首先编写对应的SQL，要完成的功能

1、在Mapper接口里对应返回值类型

Books queryBookByName(String bookName);

2、对应Mapper里编写SQL

   <select id="queryBookByName" resultType="Books">
        select * from ssmbuild.books where bookName like CONCAT('%',#{bookName},'%')
    </select>

3、编写Service层接口（和dao里的接口一样的）

Books queryBookByName(String bookName);

4、接口实现类

public Books queryBookByName(String bookName) {
        return bookMapper.queryBookByName(bookName);
    }

5、对应页面添加表单

<div class="col-md-4 column">
    <form class="form-inline" action="${pageContext.request.contextPath}/query" method="post">
        <span style="color: red; font-weight: bold" >${error}</span>
        <input type="text" name="queryBookName" placeholder="请输入要查询的书籍名称" required>
        <input type="submit" value="查询">
    </form>
</div>

6、对应Controller    /query

@RequestMapping("/query")
public String query(String queryBookName,Model model){
    Books book=bookService.queryBookByName(queryBookName);
    if (book==null){
        model.addAttribute("error","未找到");
        List<Books> books=bookService.queryAllBook();
        model.addAttribute("list",books);
        return "allBook";
    }
    List<Books> books=new ArrayList<Books>();
    books.add(book);
    model.addAttribute("list",books);
    return "allBook";
}