本篇内容主要讲解“JavaWeb分页查询功能怎么实现”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“JavaWeb分页查询功能怎么实现”吧!
效果：
实现：
分页查询有几个比较重要的参数，pageNum当前的页数，pageSize每页所展示的数据，totalRecord总共有多少数据，其他的数据可以根据这三个数据得出，有了这几个数据就可以分页查询了
计算
安全
数据库
网络和加速
企业服务
public class Page { //当前的页数
private int pageNum; //每页所展示的数据
private int pageSize; //总共有多少数据
private int totalRecord; //总页数
private int totalPage; //查询数据的起始位置
private int startIndex; //存放查询到的数据
private List<Book> booklist; //相对的头页
private int start; //相对的尾页
private int end;
public Page(int pageNum, int pageSize, int totalRecord) { this.pageNum = pageNum; this.pageSize = pageSize; this.totalRecord = totalRecord;
if(totalRecord%pageSize == 0){ //如果刚好能够整除，则totalPage = totalRecord/pageSize
this.totalPage = totalRecord/pageSize;
}else{ //如歌不能整除，则需要多加一页显示余下的数据
this.totalPage = (totalRecord/pageSize)+1;
} this.startIndex = (pageNum-1)*pageSize; //初始头页
this.start = 1; //初始尾页
this.end = 5; if(totalPage<5){ //如果总页数小于5页，则尾页为总页数
this.end = this.totalPage;
}else{ this.start = this.pageNum-2; this.end = this.pageNum+2; if(this.start<0){ this.start = 1; this.end = 5;
} if(this.end>totalPage){ this.end = totalPage; this.start = this.end-5;
}
}
}
//下面的为get/set方法
public int getPageNum() { return pageNum;
}
public void setPageNum(int pageNum) { this.pageNum = pageNum;
}
public int getPageSize() { return pageSize;
}
public void setPageSize(int pageSize) { this.pageSize = pageSize;
}
public int getTotalRecord() { return totalRecord;
}
public void setTotalRecord(int totalRecord) { this.totalRecord = totalRecord;
}
public int getTotalPage() { return totalPage;
}
public void setTotalPage(int totalPage) { this.totalPage = totalPage;
}
public int getStartIndex() { return startIndex;
} public void setStartIndex(int startIndex) { this.startIndex = startIndex;
}
public List<Book> getBooklist() { return booklist;
}
public void setBooklist(List<Book> booklist) { this.booklist = booklist;
}
public int getStart() { return start;
}
public void setStart(int start) { this.start = start;
}
public int getEnd() { return end;
}
public void setEnd(int end) { this.end = end;
}
}pageNum从请求中获得，pageSize自己设置，totalRecord通过mybatis查询获得，一开始登录的时候请求中没有pageNum，所以进行一个判断，如果没有pageNum则赋值为1
//pageNum
String pageNum = request.getParameter("pageNum") == null?"1":request.getParameter("pageNum");//pageSize
int pageSize = 7;//totalRecordint totalRecord = bookMapper.BookSize();//mybatis<select id="BookSize" resultType="int"> select count(*) from book
</select>有了pageNum和startIndex就可以查询到特定范围的数据，通过使用mysql中的limit函数，limit有两个参数，第一个参数为起始位置，即从那开始查，第二个参数为查询范围，即查多少个，如 limit 14,7 为从第14个数据开始往后查七个。
<select id="Books" parameterType="java.util.Map" resultType="book"> select *from book limit #{startIndex},#{pageSize}
</select>public static Page getPageUser(int pageNum,int pageSize){
SqlSession sqlSession = GetSqlSession.getSqlSession();
BookMapper bookMapper = sqlSession.getMapper(BookMapper.class); int totalRecord = bookMapper.BookSize();
Page page = new Page(pageNum,pageSize ,totalRecord ); int startIndex = page.getStartIndex();
Map<String,Integer> map = new HashMap<>(); map.put("startIndex",startIndex ); map.put("pageSize",pageSize );
page.setBooklist(bookMapper.Books(map)); return page;
}jsp页面：
<a href="index?pageNum=1">首页</a>
<%--当前页数为第一页--%>
<c:if test="${sessionScope.page.pageNum == 1}">
<c:forEach begin="${sessionScope.page.start}" end="${sessionScope.page.end}" step="1" var="i">
<c:if test="${sessionScope.page.pageNum == i}">
<span style="color: deeppink">${i}</span>
</c:if>
<c:if test="${sessionScope.page.pageNum != i}">
<a href="index?pageNum=${i}">${i}</a>
</c:if>
</c:forEach>
<a href="index?pageNum=${sessionScope.page.pageNum+1}">下一页</a>
</c:if>
<%--当前页数为中间页数--%>
<c:if test="${sessionScope.page.pageNum >1 && sessionScope.page.pageNum<sessionScope.page.totalPage}">
<a href="index?pageNum=${sessionScope.page.pageNum-1}">上一页</a>
<c:forEach begin="${sessionScope.page.start}" end="${sessionScope.page.end}" step="1" var="i">
<c:if test="${sessionScope.page.pageNum == i}">
<span style="color: deeppink">${i}</span>
</c:if>
<c:if test="${sessionScope.page.pageNum != i}">
<a href="index?pageNum=${i}">${i}</a>
</c:if>
</c:forEach>
<a href="index?pageNum=${sessionScope.page.pageNum+1}">下一页</a>
</c:if>
<%--当前页数为最后一页--%>
<c:if test="${sessionScope.page.pageNum == sessionScope.page.totalPage}">
<a href="index?pageNum=${sessionScope.page.pageNum-1}">上一页</a>
<c:forEach begin="${sessionScope.page.start}" end="${sessionScope.page.end}" step="1" var="i">
<c:if test="${sessionScope.page.pageNum == i}">
<span style="color: deeppink">${i}</span>
</c:if>
<c:if test="${sessionScope.page.pageNum != i}">
<a href="index?pageNum=${i}">${i}</a>
</c:if>
</c:forEach>
</c:if>
<a href="index?pageNum=${sessionScope.page.totalPage}">尾页</a>到此，相信大家对“JavaWeb分页查询功能怎么实现”有了更深的了解，不妨来实际操作一番吧！这里是亿速云网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！
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