关于分页的处理

public class UserReportVo {
private String uid;
/**
* 分页对象
*/
private Page<UserReportVo> page;

public Page<UserReportVo> getPage() {
return page;
}
public void setPage(Page<UserReportVo> page) {
this.page = page;
}
public String getUid() {
return uid;
}
public void setUid(String uid) {
this.uid = uid;
}

}

public class Page<T> {

protected int pageNo = 1; // 当前页码
protected int pageSize = Integer.valueOf(Global.getConfig("page.pageSize")); // 页面大小,设置为“-1”表示不进行分页(分页无效)

protected long count;// 总记录数,设置为“-1”表示不查询总数

protected int first;// 首页索引
protected int last;// 尾页索引
protected int prev;// 上一页索引
protected int next;// 下一页索引

private boolean firstPage;//是否是第一页
private boolean lastPage;//是否是最后一页

protected int length = 8;// 显示页面长度
protected int slider = 1;// 前后显示页面长度

private List<T> list = new ArrayList<T>();

private String orderBy = ""; // 标准查询有效, 实例: updatedate desc, name asc

protected String funcName = "page"; // 设置点击页码调用的js函数名称,默认为page,在一页有多个分页对象时使用。

protected String funcParam = ""; // 函数的附加参数,第三个参数值。

private String message = ""; // 设置提示消息,显示在“共n条”之后

public Page() {
this.pageSize = -1;
}

/**
* 构造方法
* @param request 传递 repage 参数,来记住页码
* @param response 用于设置 Cookie,记住页码
*/
public Page(HttpServletRequest request, HttpServletResponse response){
this(request, response, -2);
}

/**
* 构造方法
* @param request 传递 repage 参数,来记住页码
* @param response 用于设置 Cookie,记住页码
* @param defaultPageSize 默认分页大小,如果传递 -1 则为不分页,返回所有数据
*/
public Page(HttpServletRequest request, HttpServletResponse response, int defaultPageSize){
// 设置页码参数(传递repage参数,来记住页码)
String no = request.getParameter("pageNo");
if (StringUtils.isNumeric(no)){
CookieUtils.setCookie(response, "pageNo", no);
this.setPageNo(Integer.parseInt(no));
}else if (request.getParameter("repage")!=null){
no = CookieUtils.getCookie(request, "pageNo");
if (StringUtils.isNumeric(no)){
this.setPageNo(Integer.parseInt(no));
}
}
// 设置页面大小参数(传递repage参数,来记住页码大小)
String size = request.getParameter("pageSize");
if (StringUtils.isNumeric(size)){
CookieUtils.setCookie(response, "pageSize", size);
this.setPageSize(Integer.parseInt(size));
}else if (request.getParameter("repage")!=null){
no = CookieUtils.getCookie(request, "pageSize");
if (StringUtils.isNumeric(size)){
this.setPageSize(Integer.parseInt(size));
}
}else if (defaultPageSize != -2){
this.pageSize = defaultPageSize;
}
// 设置排序参数
String orderBy = request.getParameter("orderBy");
if (StringUtils.isNotBlank(orderBy)){
this.setOrderBy(orderBy);
}
}

/**
* 构造方法
* @param pageNo 当前页码
* @param pageSize 分页大小
*/
public Page(int pageNo, int pageSize) {
this(pageNo, pageSize, 0);
}

/**
* 构造方法
* @param pageNo 当前页码
* @param pageSize 分页大小
* @param count 数据条数
*/
public Page(int pageNo, int pageSize, long count) {
this(pageNo, pageSize, count, new ArrayList<T>());
}

/**
* 构造方法
* @param pageNo 当前页码
* @param pageSize 分页大小
* @param count 数据条数
* @param list 本页数据对象列表
*/
public Page(int pageNo, int pageSize, long count, List<T> list) {
this.setCount(count);
this.setPageNo(pageNo);
this.pageSize = pageSize;
this.list = list;
}

/**
* 初始化参数
*/
public void initialize(){

//1
this.first = 1;

this.last = (int)(count / (this.pageSize < 1 ? 20 : this.pageSize) + first - 1);

if (this.count % this.pageSize != 0 || this.last == 0) {
this.last++;
}

if (this.last < this.first) {
this.last = this.first;
}

if (this.pageNo <= 1) {
this.pageNo = this.first;
this.firstPage=true;
}

if (this.pageNo >= this.last) {
this.pageNo = this.last;
this.lastPage=true;
}

if (this.pageNo < this.last - 1) {
this.next = this.pageNo + 1;
} else {
this.next = this.last;
}

if (this.pageNo > 1) {
this.prev = this.pageNo - 1;
} else {
this.prev = this.first;
}

//2
if (this.pageNo < this.first) {// 如果当前页小于首页
this.pageNo = this.first;
}

if (this.pageNo > this.last) {// 如果当前页大于尾页
this.pageNo = this.last;
}

}

/**
* 默认输出当前分页标签
* <div class="page">${page}</div>
*/
@Override
public String toString() {

StringBuilder sb = new StringBuilder();
sb.append("<div class="span5" style="display: inline;">");
long startIndex = (pageNo-1)*pageSize + 1;
long endIndex = pageNo*pageSize <=count? pageNo*pageSize:count;

sb.append("<div class="dataTables_info">");
sb.append("<span >显示第 "+startIndex+" 到第 "+ endIndex +" 条,总共 "+count+" 条</span>");
sb.append("<span >每页显示 <span class="btn-group dropup">");
sb.append("<button type="button" class="btn btn-default btn-outline dropdown-toggle" data-toggle="dropdown" aria-expanded="false">");
sb.append("<span class="page-size">"+pageSize+"</span> <span class="caret"></span>");
sb.append("</button>");
sb.append("<ul class="dropdown-menu" role="menu">");
sb.append("<li class=""+getSelected(pageSize,10)+ ""><a href="javascript:"+funcName+"("+pageNo+",10,'"+funcParam+"');">10</a></li>");
sb.append("<li class=""+getSelected(pageSize,25)+ ""><a href="javascript:"+funcName+"("+pageNo+",25,'"+funcParam+"');">25</a></li>");
sb.append("<li class=""+getSelected(pageSize,50)+ ""><a href="javascript:"+funcName+"("+pageNo+",50,'"+funcParam+"');">50</a></li>");
sb.append("<li class=""+getSelected(pageSize,100)+ ""><a href="javascript:"+funcName+"("+pageNo+",100,'"+funcParam+"');">100</a></li>");
sb.append("</ul>");
sb.append("</span> 条记录</span>");
sb.append("</div>");
sb.append("</div>");


sb.append("<div class="span7" style="display: inline;">");
sb.append("<div class="dataTables_paginate paging_bootstrap pagination">");
sb.append("<ul class="pagination pagination-outline">");
if (pageNo == first) {// 如果是首页
sb.append("<li class="prev disabled"><a href="javascript:">首页</a></li> ");
sb.append("<li class="prev disabled"><a href="javascript:">上一页</a></li> ");
} else {
sb.append("<li class="prev"><a href="javascript:" onclick=""+funcName+"("+first+","+pageSize+",'"+funcParam+"');">"
+ "首页></a></li> ");
sb.append("<li class="prev"><a href="javascript:" onclick=""+funcName+"("+prev+","+pageSize+",'"+funcParam+"');">"
+ "上一页</a></li> ");
}

int begin = pageNo - (length / 2);

if (begin < first) {
begin = first;
}

int end = begin + length - 1;

if (end >= last) {
end = last;
begin = end - length + 1;
if (begin < first) {
begin = first;
}
}

if (begin > first) {
int i = 0;
for (i = first; i < first + slider && i < begin; i++) {
sb.append("<li><a href="javascript:" onclick=""+funcName+"("+i+","+pageSize+",'"+funcParam+"');">"
+ (i + 1 - first) + "</a></li> ");
}
if (i < begin) {
sb.append("<li><a href="javascript:">...</a></li> ");
}
}

for (int i = begin; i <= end; i++) {
if (i == pageNo) {
sb.append("<li class="active"><a href="javascript:">" + (i + 1 - first)
+ "</a></li> ");
} else {
sb.append("<li><a href="javascript:" onclick=""+funcName+"("+i+","+pageSize+",'"+funcParam+"');">"
+ (i + 1 - first) + "</a></li> ");
}
}

if (last - end > slider) {
sb.append("<li class="disabled"><a href="javascript:">...</a></li> ");
end = last - slider;
}

for (int i = end + 1; i <= last; i++) {
sb.append("<li><a href="javascript:" onclick=""+funcName+"("+i+","+pageSize+",'"+funcParam+"');">"
+ (i + 1 - first) + "</a></li> ");
}

if (pageNo == last) {
sb.append("<li class="next disabled"><a href="javascript:">下一页</a></li> ");
sb.append("<li class="next disabled"><a href="javascript:">尾页</a></li> ");
} else {
sb.append("<li class="next"><a href="javascript:" onclick=""+funcName+"("+next+","+pageSize+",'"+funcParam+"');">"
+ "下一页</a></li> ");
sb.append("<li class="next"><a href="javascript:" onclick=""+funcName+"("+last+","+pageSize+",'"+funcParam+"');">"
+ "尾页</a></li> ");
}

sb.append("</ul>");
sb.append("</div>");
sb.append("</div>");
sb.append("</div>");
return sb.toString();
}

protected String getSelected(int pageNo, int selectedPageNo){
if(pageNo == selectedPageNo){
//return "selected";
return "active";
}else{
return "";
}

}
/**
* 获取分页HTML代码
* @return
*/
public String getHtml(){
return toString();
}

/**
* 获取设置总数
* @return
*/
public long getCount() {
return count;
}

/**
* 设置数据总数
* @param count
*/
public void setCount(long count) {
this.count = count;
if (pageSize >= count){
pageNo = 1;
}
}

/**
* 获取当前页码
* @return
*/
public int getPageNo() {
return pageNo;
}

/**
* 设置当前页码
* @param pageNo
*/
public void setPageNo(int pageNo) {
this.pageNo = pageNo;
}

/**
* 获取页面大小
* @return
*/
public int getPageSize() {
return pageSize;
}

/**
* 设置页面大小(最大500)
* @param pageSize
*/
public void setPageSize(int pageSize) {
this.pageSize = pageSize <= 0 ? 10 : pageSize;// > 500 ? 500 : pageSize;
}

/**
* 首页索引
* @return
*/
@JsonIgnore
public int getFirst() {
return first;
}

/**
* 尾页索引
* @return
*/
@JsonIgnore
public int getLast() {
return last;
}

/**
* 获取页面总数
* @return getLast();
*/
@JsonIgnore
public int getTotalPage() {
return getLast();
}

/**
* 是否为第一页
* @return
*/
@JsonIgnore
public boolean isFirstPage() {
return firstPage;
}

/**
* 是否为最后一页
* @return
*/
@JsonIgnore
public boolean isLastPage() {
return lastPage;
}

/**
* 上一页索引值
* @return
*/
@JsonIgnore
public int getPrev() {
if (isFirstPage()) {
return pageNo;
} else {
return pageNo - 1;
}
}

/**
* 下一页索引值
* @return
*/
@JsonIgnore
public int getNext() {
if (isLastPage()) {
return pageNo;
} else {
return pageNo + 1;
}
}

/**
* 获取本页数据对象列表
* @return List<T>
*/
public List<T> getList() {
return list;
}

/**
* 设置本页数据对象列表
* @param list
*/
public Page<T> setList(List<T> list) {
this.list = list;
initialize();
return this;
}

/**
* 获取查询排序字符串
* @return
*/
@JsonIgnore
public String getOrderBy() {
// SQL过滤,防止注入
String reg = "(?:')|(?:--)|(/\*(?:.|[\n\r])*?\*/)|"
+ "(\b(select|update|and|or|delete|insert|trancate|char|into|substr|ascii|declare|exec|count|master|into|drop|execute)\b)";
Pattern sqlPattern = Pattern.compile(reg, Pattern.CASE_INSENSITIVE);
if (sqlPattern.matcher(orderBy).find()) {
return "";
}
return orderBy;
}

/**
* 设置查询排序,标准查询有效, 实例: updatedate desc, name asc
*/
public void setOrderBy(String orderBy) {
this.orderBy = orderBy;
}

/**
* 获取点击页码调用的js函数名称
* function ${page.funcName}(pageNo){location="${ctx}/list-${category.id}${urlSuffix}?pageNo="+i;}
* @return
*/
@JsonIgnore
public String getFuncName() {
return funcName;
}

/**
* 设置点击页码调用的js函数名称,默认为page,在一页有多个分页对象时使用。
* @param funcName 默认为page
*/
public void setFuncName(String funcName) {
this.funcName = funcName;
}

/**
* 获取分页函数的附加参数
* @return
*/
@JsonIgnore
public String getFuncParam() {
return funcParam;
}

/**
* 设置分页函数的附加参数
* @return
*/
public void setFuncParam(String funcParam) {
this.funcParam = funcParam;
}

/**
* 设置提示消息,显示在“共n条”之后
* @param message
*/
public void setMessage(String message) {
this.message = message;
}

/**
* 分页是否有效
* @return this.pageSize==-1
*/
@JsonIgnore
public boolean isDisabled() {
return this.pageSize==-1;
}

/**
* 是否进行总数统计
* @return this.count==-1
*/
@JsonIgnore
public boolean isNotCount() {
return this.count==-1;
}

/**
* 获取 Hibernate FirstResult
*/
public int getFirstResult(){
int firstResult = (getPageNo() - 1) * getPageSize();
if (firstResult >= getCount()) {
firstResult = 0;
}
return firstResult;
}
/**
* 获取 Hibernate MaxResults
*/
public int getMaxResults(){
return getPageSize();
}
}

// 封装查询对象
UserReportVo userReportVo = new UserReportVo();
userReportVo.setUid(uid);
// 封装分页对象
Page<UserReportVo> page = new Page<UserReportVo>(pageNo,pageSize);
userReportVo.setPage(page);
List<UserReportVo> uVo =userService.getAllUserReportByUid(userReportVo);

原文地址:https://www.cnblogs.com/hwgok/p/6683541.html