com.hongqiang.shop.common.persistence.Page.java Source code

Java tutorial

Introduction

Here is the source code for com.hongqiang.shop.common.persistence.Page.java

Source

/**
 * Copyright &copy; 2012-2013 <a href="https://github.com/thinkgem/jeesite">JeeSite</a> All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 */
package com.hongqiang.shop.common.persistence;

import java.util.ArrayList;
import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.StringUtils;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.domain.Sort.Direction;
import org.springframework.data.domain.Sort.Order;

import com.hongqiang.shop.common.config.Global;
import com.hongqiang.shop.common.utils.CookieUtils;

/**
 * 
 * @author ThinkGem
 * @version 2013-7-2
 * @param <T>
 */
public class Page<T> {

    private int pageNo = 1; // ??
    private int pageSize = Integer.valueOf(Global.getConfig("page.pageSize")); // ??-1??

    private long count;// -1??

    private int first;// 
    private int last;// 
    private int prev;// 
    private int next;// 

    private boolean firstPage;//?
    private boolean lastPage;//??

    private int length = 8;// ?
    private int slider = 1;// ???

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

    private String orderBy = ""; //   updatedate desc, name asc

    private String funcName = "page"; // ?js??page

    private String message = ""; // ???n???

    /**
     * 
     * @param request  repage ????
     * @param response  Cookie??
     */
    public Page(HttpServletRequest request, HttpServletResponse response) {
        this(request, response, -2);
    }

    /**
     * 
     * @param request  repage ????
     * @param response  Cookie??
     * @param pageSize ? -1 ??
     */
    public Page(HttpServletRequest request, HttpServletResponse response, int pageSize) {
        // ??repage????
        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));
            }
        }
        // ???repage?????
        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));
            }
        }
        if (pageSize != -2) {
            this.pageSize = pageSize;
        }
        // ??
        String orderBy = request.getParameter("orderBy");
        if (StringUtils.isNotBlank(orderBy)) {
            this.setOrderBy(orderBy);
        }
    }

    /**
     * 
     * @param pageNo ??
     * @param pageSize ?
     */
    public Page(int pageNo, int pageSize) {
        this(pageNo, pageSize, 0);
    }

    /**
     * 
     * @param pageNo ??
     * @param pageSize ?
     * @param count ??
     */
    public Page(int pageNo, int pageSize, long count) {
        this(pageNo, pageSize, count, new ArrayList<T>());
    }

    /**
     * 
     * @param pageNo ??
     * @param pageSize ?
     * @param count ??
     * @param list ?
     */
    public Page(int pageNo, int pageSize, long count, List<T> list) {
        this.setCount(count);
        this.setPageNo(pageNo);
        this.pageSize = pageSize;
        this.setList(list);
    }

    /**
     * ??
     */
    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) {// ??
            this.pageNo = this.first;
        }

        if (this.pageNo > this.last) {// ?
            this.pageNo = this.last;
        }

    }

    /**
     * ? 
     * <div class="page">${page}</div>
     */
    @Override
    public String toString() {

        initialize();

        StringBuilder sb = new StringBuilder();

        if (pageNo == first) {// 
            sb.append("<li class=\"disabled\"><a href=\"javascript:\">&#171; </a></li>\n");
        } else {
            sb.append("<li><a href=\"javascript:" + funcName + "(" + prev + "," + pageSize
                    + ");\">&#171; </a></li>\n");
        }

        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:" + funcName + "(" + i + "," + pageSize + ");\">"
                        + (i + 1 - first) + "</a></li>\n");
            }
            if (i < begin) {
                sb.append("<li class=\"disabled\"><a href=\"javascript:\">...</a></li>\n");
            }
        }

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

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

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

        if (pageNo == last) {
            sb.append("<li class=\"disabled\"><a href=\"javascript:\"> &#187;</a></li>\n");
        } else {
            sb.append("<li><a href=\"javascript:" + funcName + "(" + next + "," + pageSize + ");\">"
                    + " &#187;</a></li>\n");
        }

        sb.append("<li class=\"disabled controls\"><a href=\"javascript:\">? ");
        sb.append("<input type=\"text\" value=\"" + pageNo
                + "\" onkeypress=\"var e=window.event||this;var c=e.keyCode||e.which;if(c==13)");
        sb.append(funcName + "(this.value," + pageSize + ");\" onclick=\"this.select();\"/> / ");
        sb.append("<input type=\"text\" value=\"" + pageSize
                + "\" onkeypress=\"var e=window.event||this;var c=e.keyCode||e.which;if(c==13)");
        sb.append(funcName + "(" + pageNo + ",this.value);\" onclick=\"this.select();\"/> ?");
        sb.append(" " + count + " ?" + (message != null ? message : "") + "</a><li>\n");

        sb.insert(0, "<ul>\n").append("</ul>\n");

        sb.append("<div style=\"clear:both;\"></div>");

        //      sb.insert(0,"<div class=\"page\">\n").append("</div>\n");

        return sb.toString();
    }

    //   public static void main(String[] args) {
    //      Page<String> p = new Page<String>(3, 3);
    //      System.out.println(p);
    //      System.out.println(""+p.getFirst());
    //      System.out.println(""+p.getLast());
    //      System.out.println(""+p.getPrev());
    //      System.out.println(""+p.getNext());
    //   }

    /**
     * ?
     * @return
     */
    public long getCount() {
        return count;
    }

    /**
     * ?
     * @param count
     */
    public void setCount(long count) {
        this.count = count;
        if (pageSize >= count) {
            pageNo = 1;
        }
    }

    /**
     * ???
     * @return
     */
    public int getPageNo() {
        return pageNo;
    }

    /**
     * ??
     * @param pageNo
     */
    public void setPageNo(int pageNo) {
        this.pageNo = pageNo;
    }

    /**
     * ???
     * @return
     */
    public int getPageSize() {
        return pageSize;
    }

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

    /**
     * 
     * @return
     */
    public int getFirst() {
        return first;
    }

    /**
     * 
     * @return
     */
    public int getLast() {
        return last;
    }

    /**
     * ??
     * @return getLast();
     */
    public int getTotalPage() {
        return getLast();
    }

    /**
     * ?
     * @return
     */
    public boolean isFirstPage() {
        return firstPage;
    }

    /**
     * ??
     * @return
     */
    public boolean isLastPage() {
        return lastPage;
    }

    /**
     * 
     * @return
     */
    public int getPrev() {
        if (isFirstPage()) {
            return pageNo;
        } else {
            return pageNo - 1;
        }
    }

    /**
     * 
     * @return
     */
    public int getNext() {
        if (isLastPage()) {
            return pageNo;
        } else {
            return pageNo + 1;
        }
    }

    /**
     * ??
     * @return List<T>
     */
    public List<T> getList() {
        return list;
    }

    /**
     * ?
     * @param list
     */
    public void setList(List<T> list) {
        this.list = list;
    }

    /**
     * ??
     * @return
     */
    public String getOrderBy() {
        return orderBy;
    }

    /**
     * ?  updatedate desc, name asc
     */
    public void setOrderBy(String orderBy) {
        this.orderBy = orderBy;
    }

    /**
     * ??js??
     * function ${page.funcName}(pageNo){location="${ctx}/list-${category.id}${urlSuffix}?pageNo="+i;}
     * @return
     */
    public String getFuncName() {
        return funcName;
    }

    /**
     * ?js??page
     * @param funcName page
     */
    public void setFuncName(String funcName) {
        this.funcName = funcName;
    }

    /**
     * ???n???
     * @param message
     */
    public void setMessage(String message) {
        this.message = message;
    }

    /**
     * ?
     * @return this.pageSize==-1
     */
    public boolean isDisabled() {
        return this.pageSize == -1;
    }

    /**
     * ?
     * @return this.count==-1
     */
    public boolean isNotCount() {
        return this.count == -1;
    }

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

    /**
     * ? Hibernate MaxResults
     */
    public int getMaxResults() {
        return getPageSize();
    }

    /**
     * ? Spring data JPA 
     */
    public Pageable getSpringPage() {
        List<Order> orders = new ArrayList<Order>();
        if (orderBy != null) {
            for (String order : StringUtils.split(orderBy, ",")) {
                String[] o = StringUtils.split(order, " ");
                if (o.length == 1) {
                    orders.add(new Order(Direction.ASC, o[0]));
                } else if (o.length == 2) {
                    if ("DESC".equals(o[1].toUpperCase())) {
                        orders.add(new Order(Direction.DESC, o[0]));
                    } else {
                        orders.add(new Order(Direction.ASC, o[0]));
                    }
                }
            }
        }
        return new PageRequest(this.pageNo - 1, this.pageSize, new Sort(orders));
    }

    /**
     *  Spring data JPA ?
     */
    public void setSpringPage(org.springframework.data.domain.Page<T> page) {
        this.pageNo = page.getNumber();
        this.pageSize = page.getSize();
        this.count = page.getTotalElements();
        this.list = page.getContent();
    }

}