/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2017 abel533@gmail.com
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.github.pagehelper;
import java.util.Collection;
import java.util.List;
/**
* 對Page<E>結果進行包裝
* <p/>
* 新增分頁的多項屬性,主要參考:http://bbs.csdn.net/topics/360010907
*
* @author liuzh/abel533/isea533
* @version 3.3.0
* @since 3.2.2
* 項目地址 : http://git.oschina.net/free/Mybatis_PageHelper
*/
@SuppressWarnings({"rawtypes", "unchecked"})
public class PageInfo<T> extends PageSerializable<T> {
//當前頁
private int pageNum;
//每頁的數量
private int pageSize;
//當前頁的數量
private int size;
//因爲startRow和endRow不經常使用,這裏說個具體的用法
//能夠在頁面中"顯示startRow到endRow 共size條數據"
//當前頁面第一個元素在數據庫中的行號
private int startRow;
//當前頁面最後一個元素在數據庫中的行號
private int endRow;
//總頁數
private int pages;
//前一頁
private int prePage;
//下一頁
private int nextPage;
//是否爲第一頁
private boolean isFirstPage = false;
//是否爲最後一頁
private boolean isLastPage = false;
//是否有前一頁
private boolean hasPreviousPage = false;
//是否有下一頁
private boolean hasNextPage = false;
//導航頁碼數
private int navigatePages;
//全部導航頁號
private int[] navigatepageNums;
//導航條上的第一頁
private int navigateFirstPage;
//導航條上的最後一頁
private int navigateLastPage;
public PageInfo() {
}
/**
* 包裝Page對象
*
* @param list
*/
public PageInfo(List<T> list) {
this(list, 8);
}
/**
* 包裝Page對象
*
* @param list page結果
* @param navigatePages 頁碼數量
*/
public PageInfo(List<T> list, int navigatePages) {
super(list);
if (list instanceof Page) {
Page page = (Page) list;
this.pageNum = page.getPageNum();
this.pageSize = page.getPageSize();
this.pages = page.getPages();
this.size = page.size();
//因爲結果是>startRow的,因此實際的須要+1
if (this.size == 0) {
this.startRow = 0;
this.endRow = 0;
} else {
this.startRow = page.getStartRow() + 1;
//計算實際的endRow(最後一頁的時候特殊)
this.endRow = this.startRow - 1 + this.size;
}
} else if (list instanceof Collection) {
this.pageNum = 1;
this.pageSize = list.size();
this.pages = this.pageSize > 0 ? 1 : 0;
this.size = list.size();
this.startRow = 0;
this.endRow = list.size() > 0 ? list.size() - 1 : 0;
}
if (list instanceof Collection) {
this.navigatePages = navigatePages;
//計算導航頁
calcNavigatepageNums();
//計算先後頁,第一頁,最後一頁
calcPage();
//判斷頁面邊界
judgePageBoudary();
}
}
public static <T> PageInfo<T> of(List<T> list) {
return new PageInfo<T>(list);
}
public static <T> PageInfo<T> of(List<T> list, int navigatePages) {
return new PageInfo<T>(list, navigatePages);
}
/**
* 計算導航頁
*/
private void calcNavigatepageNums() {
//當總頁數小於或等於導航頁碼數時
if (pages <= navigatePages) {
navigatepageNums = new int[pages];
for (int i = 0; i < pages; i++) {
navigatepageNums[i] = i + 1;
}
} else { //當總頁數大於導航頁碼數時
navigatepageNums = new int[navigatePages];
int startNum = pageNum - navigatePages / 2;
int endNum = pageNum + navigatePages / 2;
if (startNum < 1) {
startNum = 1;
//(最前navigatePages頁
for (int i = 0; i < navigatePages; i++) {
navigatepageNums[i] = startNum++;
}
} else if (endNum > pages) {
endNum = pages;
//最後navigatePages頁
for (int i = navigatePages - 1; i >= 0; i--) {
navigatepageNums[i] = endNum--;
}
} else {
//全部中間頁
for (int i = 0; i < navigatePages; i++) {
navigatepageNums[i] = startNum++;
}
}
}
}
/**
* 計算先後頁,第一頁,最後一頁
*/
private void calcPage() {
if (navigatepageNums != null && navigatepageNums.length > 0) {
navigateFirstPage = navigatepageNums[0];
navigateLastPage = navigatepageNums[navigatepageNums.length - 1];
if (pageNum > 1) {
prePage = pageNum - 1;
}
if (pageNum < pages) {
nextPage = pageNum + 1;
}
}
}
/**
* 斷定頁面邊界
*/
private void judgePageBoudary() {
isFirstPage = pageNum == 1;
isLastPage = pageNum == pages || pages == 0;
hasPreviousPage = pageNum > 1;
hasNextPage = pageNum < pages;
}
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 getSize() {
return size;
}
public void setSize(int size) {
this.size = size;
}
public int getStartRow() {
return startRow;
}
public void setStartRow(int startRow) {
this.startRow = startRow;
}
public int getEndRow() {
return endRow;
}
public void setEndRow(int endRow) {
this.endRow = endRow;
}
public int getPages() {
return pages;
}
public void setPages(int pages) {
this.pages = pages;
}
public int getPrePage() {
return prePage;
}
public void setPrePage(int prePage) {
this.prePage = prePage;
}
public int getNextPage() {
return nextPage;
}
public void setNextPage(int nextPage) {
this.nextPage = nextPage;
}
public boolean isIsFirstPage() {
return isFirstPage;
}
public void setIsFirstPage(boolean isFirstPage) {
this.isFirstPage = isFirstPage;
}
public boolean isIsLastPage() {
return isLastPage;
}
public void setIsLastPage(boolean isLastPage) {
this.isLastPage = isLastPage;
}
public boolean isHasPreviousPage() {
return hasPreviousPage;
}
public void setHasPreviousPage(boolean hasPreviousPage) {
this.hasPreviousPage = hasPreviousPage;
}
public boolean isHasNextPage() {
return hasNextPage;
}
public void setHasNextPage(boolean hasNextPage) {
this.hasNextPage = hasNextPage;
}
public int getNavigatePages() {
return navigatePages;
}
public void setNavigatePages(int navigatePages) {
this.navigatePages = navigatePages;
}
public int[] getNavigatepageNums() {
return navigatepageNums;
}
public void setNavigatepageNums(int[] navigatepageNums) {
this.navigatepageNums = navigatepageNums;
}
public int getNavigateFirstPage() {
return navigateFirstPage;
}
public int getNavigateLastPage() {
return navigateLastPage;
}
public void setNavigateFirstPage(int navigateFirstPage) {
this.navigateFirstPage = navigateFirstPage;
}
public void setNavigateLastPage(int navigateLastPage) {
this.navigateLastPage = navigateLastPage;
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder("PageInfo{");
sb.append("pageNum=").append(pageNum);
sb.append(", pageSize=").append(pageSize);
sb.append(", size=").append(size);
sb.append(", startRow=").append(startRow);
sb.append(", endRow=").append(endRow);
sb.append(", total=").append(total);
sb.append(", pages=").append(pages);
sb.append(", list=").append(list);
sb.append(", prePage=").append(prePage);
sb.append(", nextPage=").append(nextPage);
sb.append(", isFirstPage=").append(isFirstPage);
sb.append(", isLastPage=").append(isLastPage);
sb.append(", hasPreviousPage=").append(hasPreviousPage);
sb.append(", hasNextPage=").append(hasNextPage);
sb.append(", navigatePages=").append(navigatePages);
sb.append(", navigateFirstPage=").append(navigateFirstPage);
sb.append(", navigateLastPage=").append(navigateLastPage);
sb.append(", navigatepageNums=");
if (navigatepageNums == null) {
sb.append("null");
} else {
sb.append('[');
for (int i = 0; i < navigatepageNums.length; ++i) {
sb.append(i == 0 ? "" : ", ").append(navigatepageNums[i]);
}
sb.append(']');
}
sb.append('}');
return sb.toString();
}
}