Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )vxVg*.Ee
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 !Q\X)C
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 (d1V1t2r6
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 G`&'Bt{Z*
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分页支持类: =#J9
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java代码: <$Xn:B<H
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package com.javaeye.common.util; mOgx&ns;j
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import java.util.List; <PH3gyC
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publicclass PaginationSupport { 9p!d Q x
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publicfinalstaticint PAGESIZE = 30; Qq6%53
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privateint pageSize = PAGESIZE; L|vaTidc0
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privateList items; 1WZKQeOo
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privateint totalCount; Z.Lx^h+U
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privateint[] indexes = newint[0]; .l" _K
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privateint startIndex = 0; ]&; G\9$y
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public PaginationSupport(List items, int -#:Y+"'
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totalCount){ |O #w dnYW
setPageSize(PAGESIZE); !)=#p9
setTotalCount(totalCount); ,DW0A//
setItems(items); Ji)a%j1V9
setStartIndex(0); CgaB) `.
} 6-Vl#Lyb
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public PaginationSupport(List items, int INeWi= 1
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totalCount, int startIndex){ SvCK;$:
setPageSize(PAGESIZE); w2RESpi
setTotalCount(totalCount); 9^=t@
setItems(items); gGceK^#
setStartIndex(startIndex); 1yY'hb,0
} jtlDS f#
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public PaginationSupport(List items, int %K/G+
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totalCount, int pageSize, int startIndex){ X.W#=$;$:
setPageSize(pageSize); 0n =9TmE
setTotalCount(totalCount); 8#d99dOe
setItems(items); l)2HHu<
setStartIndex(startIndex); kKI!B`j=
} 6='_+{
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publicList getItems(){ N:sECGS,
return items;
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} (D+{0 /
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publicvoid setItems(List items){ KX=:)%+
this.items = items; 4jue_jsle
} e`gGzyM
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publicint getPageSize(){ }rb ]d'|
return pageSize; 8Y;zs7Y
} %`<`z yf
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publicvoid setPageSize(int pageSize){ fQ?n(
this.pageSize = pageSize; <aQ; "O~
} kAKqW7,q"
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publicint getTotalCount(){ ct|'I]nB.h
return totalCount; n!EH>'T
} D aqy+:
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publicvoid setTotalCount(int totalCount){ Wy0a2Ve
if(totalCount > 0){ 1V?Sj
this.totalCount = totalCount; >8{`q!=|~
int count = totalCount / XiZ Zo
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pageSize; He$mu=$q{
if(totalCount % pageSize > 0) hU)f(L
count++; l$bmO{8uG
indexes = newint[count]; NiQc2\4%
for(int i = 0; i < count; i++){ e&]`X HC9
indexes = pageSize * W:N"O\`{m
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i; ."#jN><t
} h0EGhJs
}else{ m6ZbYF-7W
this.totalCount = 0; ZJJl944
} ,uD*FSp>
} } k%\
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publicint[] getIndexes(){ yP=isi#dDY
return indexes; qytGs@p_
} a\2Myj
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publicvoid setIndexes(int[] indexes){ 5['B-
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this.indexes = indexes; O|g!Y(
} *fy`JC
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publicint getStartIndex(){ E0?\DvA
return startIndex; eG)/&zQ8
} ez<wEtS
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publicvoid setStartIndex(int startIndex){ jU9zCMyNF
if(totalCount <= 0) }_D5, k
this.startIndex = 0; Iy 8E$B;
elseif(startIndex >= totalCount) )PZ}^Fa
this.startIndex = indexes 3U.B[7fOM
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[indexes.length - 1]; Q*J ~wuE2
elseif(startIndex < 0) ,IvnNnl2
this.startIndex = 0; YKS'#F2
else{ $Q7E#
this.startIndex = indexes E*b[.vUp
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[startIndex / pageSize]; 'krMVC-
} an5kR_=
} TD=/C|
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publicint getNextIndex(){ BU?MRcHC
int nextIndex = getStartIndex() + U;A5-|C
{q>4:lsS
pageSize; b2@x(5#
if(nextIndex >= totalCount) e~~k}2~
return getStartIndex(); F vk:c-
else F'_8pD7
return nextIndex; <rI$"=7
} %T*+t"\)
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publicint getPreviousIndex(){ HG6{`i
int previousIndex = getStartIndex() - [/,6O
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pageSize; jN[6JY1
if(previousIndex < 0) g~["O!K3
return0; 9@EnmtR
else :/[ZgreN6
return previousIndex; J?ZVzKTb>}
} Pds*M?&F
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} I;4CvoT
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抽象业务类 3\.)y49,1
java代码: 3a[(GW _
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/** eii7pbc
* Created on 2005-7-12 m%(JRh
*/ `A{~}6jw
package com.javaeye.common.business; ;p"XCLHl
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import java.io.Serializable; <ORz`^27o
import java.util.List; Bw7:ry
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import org.hibernate.Criteria; Q&'Nr3H#tZ
import org.hibernate.HibernateException; qtwmTT)
import org.hibernate.Session; F+9`G[
import org.hibernate.criterion.DetachedCriteria; [bVP2j
import org.hibernate.criterion.Projections; 0P/LW|16
import ? bg pUv
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org.springframework.orm.hibernate3.HibernateCallback; ojqX#>0K
import #zD+DBTAu
RtM.}wv;
org.springframework.orm.hibernate3.support.HibernateDaoS @Iatlz*W
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upport; &WU*cfJn)A
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import com.javaeye.common.util.PaginationSupport; R~(.uV`#j
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public abstract class AbstractManager extends "?.Wb L
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HibernateDaoSupport { m Dq,,
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privateboolean cacheQueries = false; Ri0+nJ6
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privateString queryCacheRegion; xEWa<P#.u
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publicvoid setCacheQueries(boolean 7+-}8&syu
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cacheQueries){ S60`'!y
this.cacheQueries = cacheQueries; sgsMlZ3/
} <W^~Y31:0
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publicvoid setQueryCacheRegion(String 0].5[Jo
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queryCacheRegion){ Di=6.gm[<
this.queryCacheRegion = O]!DNN
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queryCacheRegion; Gukq}ZQ d
} %LW~oI.
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publicvoid save(finalObject entity){ V-u\TiL
getHibernateTemplate().save(entity); 4f-C]N=
} @"2-tn@q_
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publicvoid persist(finalObject entity){ 9K(b Z{
getHibernateTemplate().save(entity); Q:|E
} emO!6]0gJ
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publicvoid update(finalObject entity){ _{);n$ `
getHibernateTemplate().update(entity); P=z':4,M}
} [0@i,7{ZqE
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publicvoid delete(finalObject entity){ |zlwPi.
getHibernateTemplate().delete(entity); Yuck]?#0
} 7T78S&g
^ 2tCDm5
publicObject load(finalClass entity, ]~,'[gWb
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finalSerializable id){ ;pq4El_
return getHibernateTemplate().load 2x
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(entity, id); L;<]wKs
} [rem,i+
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publicObject get(finalClass entity, <#i'3TUR
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finalSerializable id){ Jr
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return getHibernateTemplate().get "
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(entity, id); qr1^i1%\
} BZsxf'eN'
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publicList findAll(finalClass entity){ $:/1U$
return getHibernateTemplate().find("from 0jMrL\>C
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" + entity.getName()); ,P]{*uqGiB
} 0'",4=c#V
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publicList findByNamedQuery(finalString *{Vyt5
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namedQuery){ /);6 j,x
return getHibernateTemplate x8t1g,QA
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().findByNamedQuery(namedQuery); &kGSxYDk%
} (;0]V+-
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publicList findByNamedQuery(finalString query, iZF{9@
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finalObject parameter){ W%x#ps5%
return getHibernateTemplate ZO}*^
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().findByNamedQuery(query, parameter); [ q}WS5Cp
} 7O j9~3o4
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publicList findByNamedQuery(finalString query, p w8'+FX
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finalObject[] parameters){ TM9>r :j'
return getHibernateTemplate G1BVI:A&S
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().findByNamedQuery(query, parameters); W\/0&H\i
} AkF3F^
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publicList find(finalString query){ 5 ,HNb
return getHibernateTemplate().find n!2|;|$}Z
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(query); t+
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} j56Y,Tm
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publicList find(finalString query, finalObject :Wln$L$
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parameter){ 3)sqAs(
return getHibernateTemplate().find 9;jfg|x1[
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(query, parameter); Z|.z~53;
} 1*5n}cU~
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public PaginationSupport findPageByCriteria ]pb3
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(final DetachedCriteria detachedCriteria){ 9%8T09I!
return findPageByCriteria W c nYD)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); gS!M7xy
} DWDe5$^{
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public PaginationSupport findPageByCriteria Q{RHW@_/
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(final DetachedCriteria detachedCriteria, finalint X^?-Une
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startIndex){ *i|hcDk
return findPageByCriteria i
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(detachedCriteria, PaginationSupport.PAGESIZE,
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startIndex); kG E|17I
} h<uQ~CQg
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public PaginationSupport findPageByCriteria 9P]TIV.
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(final DetachedCriteria detachedCriteria, finalint fK[9<"PC0
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pageSize, k,H4<")H
finalint startIndex){ wvfCj6}S&
return(PaginationSupport) N24+P5
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getHibernateTemplate().execute(new HibernateCallback(){ 0GB6.Ggft
publicObject doInHibernate $*tuv?
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(Session session)throws HibernateException { #ws6z`mt
Criteria criteria = uzsR*x%s-
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detachedCriteria.getExecutableCriteria(session); q.*qZ\;K
int totalCount = \]^|IViIQ
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((Integer) criteria.setProjection(Projections.rowCount ,5q^/h
t
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()).uniqueResult()).intValue(); t.m
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criteria.setProjection ivt\|
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(null); f+d{^-
List items = >$}nKPC,Y
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criteria.setFirstResult(startIndex).setMaxResults i
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,L`qV
(pageSize).list(); L&eO?I=,
PaginationSupport ps = n^'{{@&(v
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new PaginationSupport(items, totalCount, pageSize, v5&WW?IBQ
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startIndex); \HR QSfGt
return ps; y`'Ly@s
} L%fWa2P'
}, true); lp4sO#>`
} E_$ST3
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public List findAllByCriteria(final ;DGp7f#9
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DetachedCriteria detachedCriteria){ a"~W1|JC"
return(List) getHibernateTemplate e{"d6pF=
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().execute(new HibernateCallback(){ YTY0N5["
publicObject doInHibernate IUzRE?Kzf
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(Session session)throws HibernateException { E#T'=f[r~
Criteria criteria = bMgp
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detachedCriteria.getExecutableCriteria(session); lG q;kIQ
return criteria.list(); JG4Tb{F=
} T
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}, true); Xa-]+_?Q
} )U8F6GIC&}
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public int getCountByCriteria(final vhT9#) HI
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DetachedCriteria detachedCriteria){ !zD| @sX{
Integer count = (Integer) GlVq<RG*
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getHibernateTemplate().execute(new HibernateCallback(){ 0ro)e~_@*
publicObject doInHibernate 3fpX
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(Session session)throws HibernateException { x<imMJ
Criteria criteria = d+=;sJ
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detachedCriteria.getExecutableCriteria(session); NmK%k jCx
return 28zt.9
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criteria.setProjection(Projections.rowCount 5C/u`{4]Hg
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()).uniqueResult(); 3<B{-z
} <;M 6s~
}, true); &u$l2hSS
return count.intValue(); |IZG`3
}
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} [4"%NY
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h%#@Xd>.
用户在web层构造查询条件detachedCriteria,和可选的 v)BUt,A
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %N>@( .
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PaginationSupport的实例ps。 R(ay&f%E
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ps.getItems()得到已分页好的结果集 4ajBMgD]KG
ps.getIndexes()得到分页索引的数组 -j<m0XUQ
ps.getTotalCount()得到总结果数 m_oBV|v{
ps.getStartIndex()当前分页索引 852$Ui|I
ps.getNextIndex()下一页索引 V.;0F%zks5
ps.getPreviousIndex()上一页索引 `Q}.9s_ri
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nbhx2@Teqe
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 jUdW o}/
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一下代码重构了。 BYP,}yzA
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我把原本我的做法也提供出来供大家讨论吧: 1 BVivEG
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首先,为了实现分页查询,我封装了一个Page类: (Z
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java代码: l0Y(9(M@
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/*Created on 2005-4-14*/ $O7>E!uVD
package org.flyware.util.page; @~/LsYA:
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/** E9QNx62
* @author Joa Ix-FJF-
* {U7j
*/ X2Y-TET
publicclass Page { amgYr$)m
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Ch
/** imply if the page has previous page */ v-4eN1OS
privateboolean hasPrePage; -,3Ka:
ZJ u\
/** imply if the page has next page */ O3B\K <l
privateboolean hasNextPage; 4LKOBiEM
'N0d==aI
/** the number of every page */ 5zfPh`U>1
privateint everyPage; ExV>s* y
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/** the total page number */ .#EmE'IP*
privateint totalPage; :8MpSvCV
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/** the number of current page */ MhHygZT[}
privateint currentPage; wIL5-k,
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/** the begin index of the records by the current wQ@@|Cj4L
EVrOu""
query */ =@&]PYv
privateint beginIndex; o=4d2V%m
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/** The default constructor */ (H0nO7Bk
public Page(){ "P'W@
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} G)iV
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/** construct the page by everyPage :8jHN_u
* @param everyPage A1>R8Zuhy
* */ !SKEL6~7
public Page(int everyPage){ @R(6w{h9
this.everyPage = everyPage; zr2%|YF
} a*KB'u6&
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/** The whole constructor */ dy#dug6j
public Page(boolean hasPrePage, boolean hasNextPage, Z_cTuu0'
f
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qP *$wKY,
int everyPage, int totalPage, :1s6h%evrT
int currentPage, int beginIndex){ '72ZLdi}-
this.hasPrePage = hasPrePage; 'l!tQD!
this.hasNextPage = hasNextPage; p 8Ts5n
this.everyPage = everyPage;
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this.totalPage = totalPage; gfFP-J3cN
this.currentPage = currentPage; x^;nQas;
this.beginIndex = beginIndex; 2Cj?k.Zk
} 6*{N{]`WZ)
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/** O83vPK
3
* @return ^1Y0JQ
* Returns the beginIndex. LH3PgGi,
*/ _Z@- q
publicint getBeginIndex(){ 0ppZ~}&
return beginIndex; #p6#,PZ
} [#$z.BoEo
y!)Z ^u
/** tA Pqbi$a
* @param beginIndex 0r.*7aXu
* The beginIndex to set. DU|0#z=*t5
*/ A#f@0W:
publicvoid setBeginIndex(int beginIndex){ Tr-gdX ;
this.beginIndex = beginIndex; X-e)w
} W{?7Pn?1`
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/** 8 U B?X
* @return =VH, i/@
* Returns the currentPage. vn KKK. E
*/
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publicint getCurrentPage(){ PGOi#x
return currentPage; )CSb\
} Lg
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/** *U)!9DvA
* @param currentPage ?6; +.h\
* The currentPage to set. K#}DXq
*/ BOoLs(p
publicvoid setCurrentPage(int currentPage){ $7T3wv9
this.currentPage = currentPage; A|O7W|"W
} x{6/di
}2|>Y[v2j
/** XA-DJ
* @return ;SEH|_/
* Returns the everyPage. 9pb4!=g*
*/ o>';-} E
publicint getEveryPage(){ 0~<d<a -@
return everyPage; w q% 4'(
} >u4%s7v
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/** +>@<'YI<
* @param everyPage EdhT;!
* The everyPage to set. )ZEUD] X
*/ tT ~}lW)Y
publicvoid setEveryPage(int everyPage){ [kDjht|$>
this.everyPage = everyPage; >c|u|^3zt
} -y1%c^36_J
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/** _O
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* @return Ayadvi(@P
* Returns the hasNextPage. 1l"A7
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*/ zC\ pd#
publicboolean getHasNextPage(){ pE[ul
return hasNextPage; \`Db|D?oy
} ?a+tL'D[
&~29 %Ns
/** *Sm$FMWQ
* @param hasNextPage FYFP6ti
* The hasNextPage to set. \H!ECTI
*/ hyH "
publicvoid setHasNextPage(boolean hasNextPage){ n\Uh5P1W"
this.hasNextPage = hasNextPage; ^z-e"
} hw:zak#j,
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/** -n?}L#4%8
* @return hu%UEB
* Returns the hasPrePage.
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*/ }xJ9EE*G/
publicboolean getHasPrePage(){ Uvgv<OR`_
return hasPrePage; .3l'&".'
} )2C_6eR
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vSE
/** K, ae-#wgb
* @param hasPrePage 0zCe|s.S&
* The hasPrePage to set. "2o,XF
*/ "gADHt=MIR
publicvoid setHasPrePage(boolean hasPrePage){ 12M&qqV
this.hasPrePage = hasPrePage; rhO
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} E)DdiB'Rh
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/** JV=d!Gi[C
* @return Returns the totalPage. ^a4 y+!
* //2G5F ;
*/ oj /:
publicint getTotalPage(){ S 0eD
2
return totalPage; 6UXa
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} (Hb
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u
/** AdxCP\S&
* @param totalPage !([Q1r{u
* The totalPage to set. (9]`3^_,J
*/ ,R5NKWo
publicvoid setTotalPage(int totalPage){ <7fF9X
this.totalPage = totalPage; ]1>U@oK
} :A%uXgK<k
uvz}qH@j/Q
} V'sp6:3*\
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8aQ\Yx
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 8 !]$ljg
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个PageUtil,负责对Page对象进行构造: [8l;X:
java代码: n|dLK.Q
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/*Created on 2005-4-14*/ P/5bNK!
package org.flyware.util.page; Xm`jD'G
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import org.apache.commons.logging.Log; h~)oiT2v
import org.apache.commons.logging.LogFactory; B- =*"H?q
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/** PLf
* @author Joa 3YVG|Bc~_
* n0 q5|ES
*/ r e.chQ6
publicclass PageUtil { Nlemb:'eP3
;
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privatestaticfinal Log logger = LogFactory.getLog gO_{(\w*
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(PageUtil.class); h<U<KO
S'#KPzy.
/** xq+$Q:f
* Use the origin page to create a new page &;S.1tg
* @param page t-*oVX3D
* @param totalRecords H6X]D"Y,
* @return Ve#VGlI
*/ Vui5Z K
publicstatic Page createPage(Page page, int GzxtC&
[ R1S+i
totalRecords){ -fIX6
return createPage(page.getEveryPage(), t"k6wv;Tq
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page.getCurrentPage(), totalRecords); E,&BP$B
} 7t= e"|^
m,NUNd#)\
/** ~9c?g(0
* the basic page utils not including exception XF(0>-
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handler ,=whwl "tA
* @param everyPage fYU/Jn#
* @param currentPage OBaG'lrZy
* @param totalRecords E:/G!1
* @return page :bFCnV`Q
*/ 3qU#Rg
;7
publicstatic Page createPage(int everyPage, int q'~?azg:
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currentPage, int totalRecords){ :fz&)e9
everyPage = getEveryPage(everyPage); awLN>KI]</
currentPage = getCurrentPage(currentPage); aTF~rAne<
int beginIndex = getBeginIndex(everyPage, Sd/?xyF1(
d~@&*1}
currentPage); -jy-KC
int totalPage = getTotalPage(everyPage, .^j 6
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totalRecords); m"*j J.MX
boolean hasNextPage = hasNextPage(currentPage, |fnP@k
>ly`1t1
totalPage); }la\?I
boolean hasPrePage = hasPrePage(currentPage); {E`[`Kf
m?bd6'&FR
returnnew Page(hasPrePage, hasNextPage, YSERQo
everyPage, totalPage, #12
currentPage, 7 wS)'zR;
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beginIndex); ZlD\)6 dZ
} "\M16N
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privatestaticint getEveryPage(int everyPage){ 5>+>=)*
return everyPage == 0 ? 10 : everyPage; 'X&sH/>r
} ov&4&v
I@IZ1
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privatestaticint getCurrentPage(int currentPage){ ;/?M&rX
return currentPage == 0 ? 1 : currentPage; 2>BWu
} !wy
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privatestaticint getBeginIndex(int everyPage, int d#E]>:w9
5VIc
currentPage){ {`5Sh1b
return(currentPage - 1) * everyPage; h.CbOI%Q
} Wm>[5h%>
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privatestaticint getTotalPage(int everyPage, int
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Im7<\ b@
totalRecords){ 'F>eieO
int totalPage = 0; ?u.&BP
, 6 P:S7
if(totalRecords % everyPage == 0) tUouO0_l
totalPage = totalRecords / everyPage; /W&R