Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z`f?7/"B
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fRxn,HyV
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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 Y3#8]Z_"}O
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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 :]4s;q:m
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分页支持类: ?VCp_Ji
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java代码: /eT9W[a
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package com.javaeye.common.util; qfdL *D
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import java.util.List; )Y&B63]B
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publicclass PaginationSupport { }
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publicfinalstaticint PAGESIZE = 30; KzX)6|g{"
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privateint pageSize = PAGESIZE; n^rbc;}
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privateList items; MskOPg
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privateint totalCount; \[|X^8j
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privateint[] indexes = newint[0]; x?]fHin_
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privateint startIndex = 0; ,gW$m~\
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public PaginationSupport(List items, int FRL;fF
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totalCount){
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setPageSize(PAGESIZE); ;1s;"
setTotalCount(totalCount); Vx:uqzw#
setItems(items); I?nU+t;
setStartIndex(0); 6kMEm)YjT
} -7XaS&.4
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public PaginationSupport(List items, int _dECAk
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totalCount, int startIndex){ 4]E1x l
setPageSize(PAGESIZE); Pqj\vdzx
setTotalCount(totalCount); R6`mmJ+'
setItems(items); 9':Hh'
setStartIndex(startIndex); _v8u%
} bMsThoePT
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public PaginationSupport(List items, int N"0>)tG
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totalCount, int pageSize, int startIndex){ <IBUl}|\
setPageSize(pageSize); *y(UI/c
setTotalCount(totalCount); dQFUQ
setItems(items); Pf;RJeD
setStartIndex(startIndex); i-#D c(9
} foBF]7Bz?
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publicList getItems(){ xIV#}z0
return items; Q/J <$W*,
} mwn$ey&QE
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publicvoid setItems(List items){ + rM]RFi
this.items = items; JaR!9GVN7
}
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publicint getPageSize(){ RQu[FZT,
return pageSize; [z*1#lj S
} dtjb(*x
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publicvoid setPageSize(int pageSize){ -O r\
this.pageSize = pageSize; !HtW~8|:
} 4N1)+W8k*
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publicint getTotalCount(){ :T>OJ"p
return totalCount; i7rk%q
} n<@C'\j@
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publicvoid setTotalCount(int totalCount){ 1(_[awBx
if(totalCount > 0){ EY.m,@{
this.totalCount = totalCount; * *oDQwW]*
int count = totalCount / Q
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pageSize; ~9,Fc6w4`+
if(totalCount % pageSize > 0) sHV?njZd
count++; LF)wn-C}
indexes = newint[count]; 0bD\`Jiv,
for(int i = 0; i < count; i++){ Au{ b1n
indexes = pageSize * 90-s@a3B-j
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i; A;6ew4
} ) 3V1aC
}else{ meXwmO
this.totalCount = 0; ^; }Y ZBy
} %sPq*w.
} $Y\7E/T
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publicint[] getIndexes(){ cBU3Q<^
return indexes; ]r%fAmj
} 3qDbfO[
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publicvoid setIndexes(int[] indexes){ bj_/
this.indexes = indexes; Z.rhM[*+0C
} /%F,
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publicint getStartIndex(){ I]pz3!On4,
return startIndex; W&[-QM8
} 5{IbKj|
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publicvoid setStartIndex(int startIndex){ k!x`cp
if(totalCount <= 0) aWP9i&
this.startIndex = 0; M"msLz
elseif(startIndex >= totalCount) <(xro/
this.startIndex = indexes 'F:Tv[qx
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[indexes.length - 1]; w4&\-S#
elseif(startIndex < 0) 3Tc90p l*t
this.startIndex = 0; FBOgaI83G
else{ Z^%HDB9^
this.startIndex = indexes 0Pt%(^
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[startIndex / pageSize]; {Q`Q2'@
} QF22_D<.}J
} `D$RL*C;M`
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publicint getNextIndex(){ }I#_H
int nextIndex = getStartIndex() + v-"nyy-&Z
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pageSize; O*n@!ye
if(nextIndex >= totalCount) l%?()]y
return getStartIndex(); 92N `Q}
else KFaYn
return nextIndex; |@f\[v9`
} ICc:k%wE7
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publicint getPreviousIndex(){ mgodvX
int previousIndex = getStartIndex() - x cZF_elt7
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pageSize; )wdd"*hv
if(previousIndex < 0) 5)0'$Xxqa0
return0; 3a}c'$F>_'
else %F}d'TPx
return previousIndex; i'1MZ%.
} *<h )q)HS
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} =8"xQ>D62
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*/|<5X;xIA
抽象业务类 o!c~"
java代码: 'TA
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/** ;hEeFJ=/G
* Created on 2005-7-12 R+=wSG ]
*/ YTr+"\CkA
package com.javaeye.common.business; am7~
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import java.io.Serializable; `joyHKZI.
import java.util.List; ,s:viXk
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import org.hibernate.Criteria; S&D8Rao5
import org.hibernate.HibernateException; N&|,!Cu
import org.hibernate.Session; gr# |ZK.`
import org.hibernate.criterion.DetachedCriteria; {M\n
import org.hibernate.criterion.Projections; a(G}<
import : JSuC
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org.springframework.orm.hibernate3.HibernateCallback; ,pVe@ d'
import $H&:R&Us
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org.springframework.orm.hibernate3.support.HibernateDaoS ::-*~CH)
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upport; "g!ek3w(
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import com.javaeye.common.util.PaginationSupport; FC]n?1?<(
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public abstract class AbstractManager extends Ue"pNjd|
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HibernateDaoSupport { X!@ Y,
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privateboolean cacheQueries = false; MN:LL
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privateString queryCacheRegion; |=V~CQ]
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publicvoid setCacheQueries(boolean |.-Muv
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cacheQueries){ 8`90a\t'Z
this.cacheQueries = cacheQueries; zw iS%-F
} u*rHKZ9i
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publicvoid setQueryCacheRegion(String *9EW&Ek
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queryCacheRegion){ x+DecO2
this.queryCacheRegion = k)W&ZY
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queryCacheRegion; POX{;[SV
} 4Tb"+Y}
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publicvoid save(finalObject entity){ gP |>gy#e
getHibernateTemplate().save(entity); ViG>gMG v
} \p]B8hLW
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publicvoid persist(finalObject entity){ @Y}G,i
getHibernateTemplate().save(entity); _>8Q{N\-
{
} 9n"MNedqH
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publicvoid update(finalObject entity){ #Jr4LQ@A9
getHibernateTemplate().update(entity); O{Z${TC[
} ;82?ACCP
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publicvoid delete(finalObject entity){ QGE0pWL-a
getHibernateTemplate().delete(entity); 8# x7q>?
} Iyb_5 UmpF
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publicObject load(finalClass entity, qVjMflVoay
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finalSerializable id){ ^`Hb7A(
return getHibernateTemplate().load kv;P2:"|
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(entity, id); RdNLf
} | IS$Om
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publicObject get(finalClass entity, IFhS(3YK[
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finalSerializable id){ )ybF@emc
return getHibernateTemplate().get 2.
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(entity, id); HV*;Yt
} 8pZ Ogh
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publicList findAll(finalClass entity){ *%E\mu,,c
return getHibernateTemplate().find("from e*U6^Xex
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" + entity.getName()); P+QL||>L
} Xg*](>/\,
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publicList findByNamedQuery(finalString 8IE^u<H(:
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namedQuery){ E>`|?DE@
return getHibernateTemplate j0s$}FPUI
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().findByNamedQuery(namedQuery); 5G$5d:[(
} !e*T.
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publicList findByNamedQuery(finalString query, U.JE \/
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finalObject parameter){ Q|e-)FS)
return getHibernateTemplate
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().findByNamedQuery(query, parameter); ^)(tO$S
} ? Dn}
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publicList findByNamedQuery(finalString query, Y*S:/b~y
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finalObject[] parameters){ TBRG
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return getHibernateTemplate P+wpX
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().findByNamedQuery(query, parameters); l5\V4
} XUD Ztxa
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publicList find(finalString query){ "F6gV;{Bt
return getHibernateTemplate().find /bPs0>5
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(query); 76KNgV)3
} ={+8jQqi1
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publicList find(finalString query, finalObject -Mz [S
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parameter){ ]}p<P):hO
return getHibernateTemplate().find "/mtuU3rt
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(query, parameter); S>S7\b'
} =O-irGms*
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public PaginationSupport findPageByCriteria -4zV
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(final DetachedCriteria detachedCriteria){ F=e-jKogK
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); z^z`{B
} fc9@l a
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public PaginationSupport findPageByCriteria -V;BkE76
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(final DetachedCriteria detachedCriteria, finalint Ak8Y?#"wz
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startIndex){ (<8}un
return findPageByCriteria c?u*,d) G
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(detachedCriteria, PaginationSupport.PAGESIZE, )*S:C
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startIndex); G$%F`R[
} w6WPfy(/2
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public PaginationSupport findPageByCriteria Pg{1' -
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(final DetachedCriteria detachedCriteria, finalint XM,slQ
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pageSize, aWJj@',_
finalint startIndex){ ^YropzHZ4E
return(PaginationSupport) &i.sSqSI5
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getHibernateTemplate().execute(new HibernateCallback(){ f-71`Pyb
publicObject doInHibernate Qh(X7B
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(Session session)throws HibernateException { PP>6
Criteria criteria = K,$rG%czX
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detachedCriteria.getExecutableCriteria(session); A`ajsZ{q,
int totalCount = -]H~D4ng
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((Integer) criteria.setProjection(Projections.rowCount 7B (%2
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()).uniqueResult()).intValue(); K +3=gBU*w
criteria.setProjection Dfa3#{
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(null); 0GXY2+p}S
List items = CgrQ"N5
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criteria.setFirstResult(startIndex).setMaxResults XNv2xuOc J
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(pageSize).list(); (6Z^0GL
PaginationSupport ps = ~rJG4U
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new PaginationSupport(items, totalCount, pageSize, m<#12#D
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startIndex); [!-gb+L
return ps; V?1 $H
} 1/2cb-V
}, true); ,<r&]
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} cgSN:$p(R
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public List findAllByCriteria(final <.B+&3')
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DetachedCriteria detachedCriteria){ T?t/[iuHrj
return(List) getHibernateTemplate .8Bo5)q$a-
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().execute(new HibernateCallback(){ d%"XsbO
publicObject doInHibernate yi>AogQ,
.
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(Session session)throws HibernateException { f$ xp74hw3
Criteria criteria = d6YXITL)\>
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detachedCriteria.getExecutableCriteria(session); m(6d3P
return criteria.list(); a[(OeVQ5
} voRry6Q;
}, true); e12QYoh
} ,_I
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public int getCountByCriteria(final IrqM_OjC
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DetachedCriteria detachedCriteria){ @we1#Vz.
Integer count = (Integer) Mzp<s<BX
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate [ 49Cvde^
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(Session session)throws HibernateException { YcN|L&R.
Criteria criteria = )ffaOS!\
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detachedCriteria.getExecutableCriteria(session); v{VF>qEP
return og5VB
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criteria.setProjection(Projections.rowCount *WQ?r&[_'
6FA+qYSV
()).uniqueResult(); pOc2V
} 5mD8$%\8
}, true); 7"!b5(4=
return count.intValue(); 'bi;Y1:
} >+P}S@
} ?K>)bA&l'
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用户在web层构造查询条件detachedCriteria,和可选的 d+D~NA[M
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 L7-BuW}&
1
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PaginationSupport的实例ps。 ew~Z/ A
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ps.getItems()得到已分页好的结果集 P1Hab2%+
ps.getIndexes()得到分页索引的数组 `
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ps.getTotalCount()得到总结果数 *c$[U{Px
ps.getStartIndex()当前分页索引 EfrQ~`\
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 N3n]
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 SIJ7Y{\.
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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 QxYm3x5
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一下代码重构了。 q? '4&
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我把原本我的做法也提供出来供大家讨论吧: da7"Q{f+
mqZH<.mn
首先,为了实现分页查询,我封装了一个Page类: hCcI]#S&
java代码: /iU<\+ H
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/*Created on 2005-4-14*/ @7twe;07r
package org.flyware.util.page; -tj#BEC[H(
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/** Z7a@$n3h
* @author Joa >^s2$@J?p
* _QL|pLf-
*/ u}@N
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publicclass Page { ba|xf@=&
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/** imply if the page has previous page */ d`^3fr'.4A
privateboolean hasPrePage; o08WC'bX
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/** imply if the page has next page */ Lv%3 jj
privateboolean hasNextPage; {N4 'g_
8;@y\0
/** the number of every page */ >n"0>[:4
privateint everyPage; NnLK!Q
[ohLG_9
/** the total page number */ FS1\`#Bm)
privateint totalPage; 0cS$S Mn{
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/** the number of current page */ 9 C[~*,qx
privateint currentPage; Nk7y2[
I%5vI}
/** the begin index of the records by the current nn7LL+h
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query */ 6!\V|
privateint beginIndex; ywwA,9~
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/** The default constructor */ ?Y4 +3`\x
public Page(){ x%viCkq
Z/ q6Q#
} yB UQ!4e
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/** construct the page by everyPage ]Dq6XR
* @param everyPage !85bpQ.
* */ gi!_Nz
public Page(int everyPage){ IuXgxR%
this.everyPage = everyPage; c]4X`3]
} #X-C~*|>j
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/** The whole constructor */ 7{m>W!
public Page(boolean hasPrePage, boolean hasNextPage, 3``JrkPI
5#.m'a)
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int everyPage, int totalPage, t2dsYU/
int currentPage, int beginIndex){ sX1DbEjj[o
this.hasPrePage = hasPrePage; 9JA@m
this.hasNextPage = hasNextPage; 1-y8Hy_a2
this.everyPage = everyPage; 6>]_H(z7
this.totalPage = totalPage; V4,Gt]4
this.currentPage = currentPage; rfwJLl/
this.beginIndex = beginIndex; a|t~&\@
}
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/** (<Cq_Kw
* @return t\Vng0
* Returns the beginIndex. %~Yo{4mHs
*/ ;Nn(
publicint getBeginIndex(){ v9f+ {Y%-
return beginIndex; jEBn"]\D
} oMbd1uus
: s
*
/** |5~Oh`w
* @param beginIndex kLgkUck8]
* The beginIndex to set. T?1BcY
*/ c(Dp`f,
publicvoid setBeginIndex(int beginIndex){ =Y2 Rht
this.beginIndex = beginIndex; 4/(#masIL
} eo]nkyYDP
A%D'Z85
-
/** !aT:0m$:9c
* @return %0Ur3
* Returns the currentPage. &~_F2]oM
*/ -}6ew@GE
publicint getCurrentPage(){ IW\^-LI.
return currentPage; _[6sr7H!
} @aS)=|Ls\
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/** sC3Vj(d!i
* @param currentPage fu!T4{2
* The currentPage to set. w9|x{B
*/ m,HE4`g
publicvoid setCurrentPage(int currentPage){ ai<qK3!O
this.currentPage = currentPage; HYdM1s6vo
} sQgz}0_=)
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/** X_78;T)uA
* @return J1w[gf]J
* Returns the everyPage. g
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*/ KdoI
publicint getEveryPage(){ a>v *
return everyPage; m"!SyN}&9?
} /r7xA}se^
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/** # xO PF9
* @param everyPage R'gd/.[e
* The everyPage to set. `CWhjL8^
*/ (2b${ Q@V
publicvoid setEveryPage(int everyPage){ cW*v))@2
this.everyPage = everyPage; 5UQ{qm*Q
} dXTD8 )&
)c11_1;
/** daSe0:daJ
* @return %Y~"Stmx
* Returns the hasNextPage. wNmpUO ?
*/ ]gBnzh.
publicboolean getHasNextPage(){
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return hasNextPage; v]SxZLa
} )WoH>D
ST{Vi';}
/** a_Xwi:e<
* @param hasNextPage .=eEuH
* The hasNextPage to set. znrO~OK
*/ {Zc8,jm
publicvoid setHasNextPage(boolean hasNextPage){ 6k hBT'n
this.hasNextPage = hasNextPage; 1hw.gn*JK>
} Vit-)o{zr
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/** z|Y54o3
* @return RI*n]HNgy+
* Returns the hasPrePage. 5 tKgm /
*/ O|t>.<T?
publicboolean getHasPrePage(){ IR${a)
return hasPrePage; aL:|Dr3SX
} D?dBm
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/** # `^nmC/F
* @param hasPrePage 1@Jp3wW
* The hasPrePage to set. M-t9M~
*/ H4ie$/[$8
publicvoid setHasPrePage(boolean hasPrePage){ $IQPB_:
this.hasPrePage = hasPrePage; *6yY>LW
} fnq 3ic"V
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/** nT?+^Ruc
* @return Returns the totalPage. 2OoANiX
* L(|K{vH h]
*/ _#V&rY&@
publicint getTotalPage(){ e :HORc~U
return totalPage; i+14!LlI
} t"B3?<?]
Ue
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/** JtO}i{A
* @param totalPage \Vme\Ke*v)
* The totalPage to set. P;.roD9
*/ v]M:HzP
publicvoid setTotalPage(int totalPage){ ;U3:1hn
this.totalPage = totalPage; yP7b))AW9
} =0?5hxM d
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} ^N^G?{EV/#
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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 +(=-95qZ
n{N0S^h
个PageUtil,负责对Page对象进行构造: 7RDmvWd-'?
java代码: H{n:R *
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/*Created on 2005-4-14*/ lW5Lwyt8
package org.flyware.util.page; +d#8/S*
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import org.apache.commons.logging.Log; =Fc]mcJ69
import org.apache.commons.logging.LogFactory; [\3ZMH
*
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/** )Lz
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* @author Joa xS UpVK
* A5j?Yts
*/ oh-EEo4,
publicclass PageUtil { s[8M$YBf
)y8Myb}
privatestaticfinal Log logger = LogFactory.getLog gIrbOMQ7
hV~M!vFxA
(PageUtil.class); WSMpX-^e@
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/** Sj I,v+
* Use the origin page to create a new page - BWf.
* @param page {d<XDx4`
* @param totalRecords qRaPh:Q'
* @return kxKb}>=
*/ f?:=@35
publicstatic Page createPage(Page page, int &jY|
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totalRecords){ Je|:\Qk
return createPage(page.getEveryPage(), ?GH/W#{o)
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page.getCurrentPage(), totalRecords); v)np.j0V7
} Pm6U:RL
R +@|#!
/** G>"n6v'^d
* the basic page utils not including exception Pl=)eq YY
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handler `^#4okg]
* @param everyPage =~J VU
* @param currentPage iDcTO}
* @param totalRecords wlP3 XF?
* @return page C&Qt*V#,
*/ 7 q!==P=
publicstatic Page createPage(int everyPage, int ^~N:lW#=
tm/>H
currentPage, int totalRecords){ /RJ]MQ\*O
everyPage = getEveryPage(everyPage); 3\4e{3$
currentPage = getCurrentPage(currentPage); EC5= 2w<
int beginIndex = getBeginIndex(everyPage, XY{N"S8
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currentPage); uDND o
int totalPage = getTotalPage(everyPage, mKu,7nMvF
-BP10-V
totalRecords); )C"ixZ>2xQ
boolean hasNextPage = hasNextPage(currentPage, $1 B?@~&
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totalPage); x*:VE57,z
boolean hasPrePage = hasPrePage(currentPage); U]}F A2
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returnnew Page(hasPrePage, hasNextPage, Io*H}$Gf
everyPage, totalPage, /ojx$Um
currentPage, qCI7)L`
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beginIndex); lr4wz(q<9
} 7_PY%4T"
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privatestaticint getEveryPage(int everyPage){ lx4pTw1
return everyPage == 0 ? 10 : everyPage; eI"pRH*f
} S'^ q
;o'r@4^&$R
privatestaticint getCurrentPage(int currentPage){ |hj!NhBe
return currentPage == 0 ? 1 : currentPage; (/nnN4\=
} DzMg^Kp
E9mu:T
privatestaticint getBeginIndex(int everyPage, int 'm`}XGUBS
.s>@@m-
currentPage){ K"VcPDK
return(currentPage - 1) * everyPage; 5?HwM[`
} 9,~7,Py }
]B;`Jf
privatestaticint getTotalPage(int everyPage, int ip<VRC5`5
Wk7E&?-:6
totalRecords){ hDTC~~J/
int totalPage = 0; .]h/M,xg
lCUYE"o
if(totalRecords % everyPage == 0) Ph]b6
totalPage = totalRecords / everyPage; NA2={RB;
else qJT/48lf_
totalPage = totalRecords / everyPage + 1 ; fQC{LcS
awo'#Y2>
return totalPage; *<S>PbqLw
} , @UOj=
`1P|<VbZ
privatestaticboolean hasPrePage(int currentPage){ $%cHplQz5
return currentPage == 1 ? false : true; ms5?^kS2O
} s&pnB
9s_^?q
privatestaticboolean hasNextPage(int currentPage, tqpO3
@Q,Q"c2
int totalPage){ \~A qA!)6
return currentPage == totalPage || totalPage == ^CLQs;zXE
s!?uLSEdb
0 ? false : true; L(C`<iE&3
} ssLswb
>w<w*pC
@%x2d1FS
} nS3Aadm
7^#f)Vp
pD({"A.x9z
MhCU;
!
,DE>:ARZ
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Jn=;gtD-*
2<B'PR-??y
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 C`t@tgT
OS;
T;
做法如下: @:Zk,
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6Jq[]l"v
u$^tRz9
的信息,和一个结果集List: WN=0s
java代码: 0D 2I)E72o
Dh8'og)7
siI%6Gn;
/*Created on 2005-6-13*/ `WXlq#:K
package com.adt.bo; h-1?c\Qq:
=3(Auchl$Y
import java.util.List; F^bY]\-5
{*B0lr`
import org.flyware.util.page.Page; C^LxuUW
^K"BQ~-w
/** $O*@Jg=
* @author Joa }r@dZBp:
*/ O%kUj&h^
publicclass Result { }ww/e\|Nt=
Bz_'>6w
private Page page; zsJ# CDm
p"
>*WQ
private List content; "."(<c/3
0)Ephsw
/** !Nx1I
* The default constructor SC~k4&xy
*/ HQ-++;Q
public Result(){ ecs 0iW-,
super(); +`GtZnt#
} ,9bnR;f\
<EUR:
/** ^C'0Y.H S
* The constructor using fields B ktRA
* SdYf^@%}F
* @param page =${.*,o
* @param content ;9OhK71}
*/ TC/c5:)]
public Result(Page page, List content){ A_9^S!
this.page = page; ]S&ki}i&
this.content = content; ]w6Q? %'9
} -sQ[f18
*"w hup[
/** 4l
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* @return Returns the content. 0i_:J
*/ * $f`ouJl
publicList getContent(){ ;B=aK"\
return content; ia'z9
} jj[6 oNKE1
fYUV[Gm
/** l{Df{1b.
* @return Returns the page. JnsJ]_<
*/ r+Ki`HD%
public Page getPage(){ O<cP1TF
return page; ;`#R9\C=h
} :Mu*E5
swF{}S"
/** t6nRg
* @param content P'U2hCif
* The content to set. x>[]Qk^?q
*/ Io.RT+slB
public void setContent(List content){ D8Fi{?A#FV
this.content = content; d{4;qM#
} y+ze`pL?
[oTe8^@[
/** !G;u
)7'v
* @param page e7U\gtZ.
* The page to set. ^-Od*DTL
*/ .}!.4J%q2
publicvoid setPage(Page page){ 7_i8'(``
this.page = page; Kb?{^\FiU
} ~'_cBJ
'XD
} ;yJ:W8U]+;
o]oiJvOr
&+2l#3}
,_3hbT8Q
tz@MZs09
2. 编写业务逻辑接口,并实现它(UserManager, 1.!U{>$
}9S}?R
UserManagerImpl) 0y9 b0G
java代码: p'
>i3T(
. ImaM
[7v|bd
/*Created on 2005-7-15*/ 5^ Qa8yA>7
package com.adt.service; !y_{mE?V(
|Ghk8 WA
import net.sf.hibernate.HibernateException; Q6Gw!!Z5EA
zi-_ l
import org.flyware.util.page.Page; #Lhv=0op
G|g^yaq>
import com.adt.bo.Result; nQc#AFg
@yuiNj.T
/** bT.q@oU
* @author Joa gN=.}$Kfu
*/ G>V6{g2Q
publicinterface UserManager { n"EKVw7Y
X 0y$xC|<
public Result listUser(Page page)throws
T^}UE<
sW[-qPK<
HibernateException; jfuHZ^ YA
qE~_}4\Z9
} y+(\:;y$7
k]@]a
A;TP~xq\
Nwi|>'\C
"313eeIt%i
java代码: {6'Xz
Z4] n<~o
}g}Eh>U
/*Created on 2005-7-15*/ !a@)6or
package com.adt.service.impl; [C "\]LiX
3$\k=q3`#
import java.util.List; W'[V$*
'h*jL@%TT
import net.sf.hibernate.HibernateException; p>B2bv+L
8 t5kou]h
import org.flyware.util.page.Page; 11=$]K>
import org.flyware.util.page.PageUtil; 'X?xn@?
jo`ZuN{
import com.adt.bo.Result; _VrY7Mz:r
import com.adt.dao.UserDAO; PXb$]HV
import com.adt.exception.ObjectNotFoundException; iEvQ4S6tD
import com.adt.service.UserManager; n<ZPWlJ
,>
zEG
/** ||Zup\QB
* @author Joa 9@
tp#
*/ V%s
g+D2
publicclass UserManagerImpl implements UserManager { 8+F5n!
Kw
-SOFE
private UserDAO userDAO; 4yl{:!la
i>F=XE
/** 3P
cVE\GN
* @param userDAO The userDAO to set. }|P3(*S
*/ .hl_zc#
publicvoid setUserDAO(UserDAO userDAO){ bNea5u##
this.userDAO = userDAO; Aedf (L7\
} xVm-4gB
_;1{feR_
/* (non-Javadoc) d?2V2`6
* @see com.adt.service.UserManager#listUser Y %JQ
V'vR(Wx
(org.flyware.util.page.Page) AcH-TIgM/
*/ H9cPtP~a)
public Result listUser(Page page)throws @]=40Yj~w
WgtLKRZ\
HibernateException, ObjectNotFoundException { $]2)r[eA)
int totalRecords = userDAO.getUserCount(); Y2H-D{a27
if(totalRecords == 0) /at7H!
throw new ObjectNotFoundException tb3VqFx
y0 * rY
("userNotExist"); d!,t_jM0
page = PageUtil.createPage(page, totalRecords); U.7fMc#
List users = userDAO.getUserByPage(page); O `}EiyV
returnnew Result(page, users); O*EV~{K
} /A=w`[<
6%v9o?:~l
} -=ZL(r
1
.G0 N+)
Luq4q95]
a{5SOe;;
#z `W ,^C
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,erw(7}'.
;5[KZ8j6Y
询,接下来编写UserDAO的代码: 8H!QekQZ]\
3. UserDAO 和 UserDAOImpl: rpR${%jc
java代码: }#XFa#
,WT>"9+
}Z!D?(
/*Created on 2005-7-15*/ %q {q.(M#
package com.adt.dao; d1j9{
2QfN.<[-
import java.util.List; drq3=2
]R__$fl`8
import org.flyware.util.page.Page; kx"10Vw
&.?XntI9O
import net.sf.hibernate.HibernateException; m~=~DMj
$<}c[Nm
/** #~ u0R>=
* @author Joa LFp "Waiv
*/ +{J8,^z#
publicinterface UserDAO extends BaseDAO { )-C3z
0'QWa{dS\
publicList getUserByName(String name)throws P15
H[<:Fz
CD|[PkjW
HibernateException; "LMj,qZ1!
%`Re{%1;
publicint getUserCount()throws HibernateException; tXD$HeBB?
bzgC+yT
publicList getUserByPage(Page page)throws \o9 \ikR
)9QtnM
HibernateException; \;LDE`Q_x
L4#pMc
} *H>rvE.K?
u;#]eUk9}
i|YS>Pw~j
bx@l6bpQ
{T){!UVp!
java代码: *b~6 B M$
p?@ %/!S
@mp`C}x"0&
/*Created on 2005-7-15*/ je4l3Hl
package com.adt.dao.impl; bDI%}k9#
6@S6E(^
import java.util.List; :2 ;Jo^6Se
KyvZ?R
import org.flyware.util.page.Page; Tb/TP3N
M>8J_{r^
import net.sf.hibernate.HibernateException; i!wU8@
import net.sf.hibernate.Query; cr7MvXF-
$vO&C6m$
import com.adt.dao.UserDAO; {K z,_bo
-%K!Ra\W
/** jmok]-pC
* @author Joa f8
d
3ZK
*/ AOf4y&B>q
public class UserDAOImpl extends BaseDAOHibernateImpl 6*OL.~WE
NkE0S`Xf
implements UserDAO { wT1s;2 %
2G8pDvBr
/* (non-Javadoc) e~'`x38
* @see com.adt.dao.UserDAO#getUserByName jN=<dq
~
P&-o>mM
(java.lang.String) <Au2e
*/ iCt.rr~;V
publicList getUserByName(String name)throws +n3I\7G>
s='+[*&&
HibernateException { DL]tg[w{
String querySentence = "FROM user in class pl[J!d.c
"
\$^j#o
com.adt.po.User WHERE user.name=:name"; }[*'
Query query = getSession().createQuery yU$MB,1
vdQoJWuB
(querySentence); S}m_XR]
query.setParameter("name", name); V7ph^^sC}
return query.list(); :Mf"
} FhE{khc#
1v o)]ff
/* (non-Javadoc) azcPeAe
* @see com.adt.dao.UserDAO#getUserCount() <N<Q9}`V
*/ +Y\:Q<eMFg
publicint getUserCount()throws HibernateException { I7f ^2
int count = 0; f)I5=Ijy(
String querySentence = "SELECT count(*) FROM tF2"IP.
~5 ^Jv m
user in class com.adt.po.User"; 3Ob.OwA
Query query = getSession().createQuery
5xY{Q
#cbgp;,M{I
(querySentence); S63Zk0(25
count = ((Integer)query.iterate().next )Q)qz$h@
BFLef3~.0
()).intValue(); 7>JYwU{
return count; `i7r]
} U=>S|>daR
k[=qx{Osx%
/* (non-Javadoc) 0lw>mxN
* @see com.adt.dao.UserDAO#getUserByPage X/!_>@`7?
xad`-vw
(org.flyware.util.page.Page) yPyu)
*/ NnZW@ln"|
publicList getUserByPage(Page page)throws t [QD#;
${Z0@G+
HibernateException { Xtp8^4Va
String querySentence = "FROM user in class 1uF$$E6[
QYJ
EUC@
com.adt.po.User"; cHFi(K]|1
Query query = getSession().createQuery 0X$mT:=9
99m2aT()
(querySentence); ,d
G. 67
query.setFirstResult(page.getBeginIndex()) ``o]i{x
.setMaxResults(page.getEveryPage()); Z`Yt~{,Q
return query.list(); pwUXM?$R
} eH&F gmU
^aFm6HS1
} 9I/b$$?D
MNT~[Z9L5G
rk=D5E7
^xo<$zn
.nV2n@SR
至此,一个完整的分页程序完成。前台的只需要调用 >J"IN I
DA=!AK>
userManager.listUser(page)即可得到一个Page对象和结果集对象 ~lj~]j
0D-`>_
的综合体,而传入的参数page对象则可以由前台传入,如果用 Obdn#Wm=
8$00\><r
webwork,甚至可以直接在配置文件中指定。 "TRS(d|3
mh
}M|h5Im
下面给出一个webwork调用示例: jW/WG tz
java代码: qHtQ4_Zn;
yzK;
vSzpx
/*Created on 2005-6-17*/ VK}4<u
package com.adt.action.user; 8&<:(mAP
rTD +7
)E
import java.util.List; ?vXgHDs^T
gLiJ&H
import org.apache.commons.logging.Log; 6W1GvM\e
import org.apache.commons.logging.LogFactory; dBWny&
import org.flyware.util.page.Page; b
F=MQ
s.3"2waZ=T
import com.adt.bo.Result; 3G})$y3m
import com.adt.service.UserService; P8 X07IK
import com.opensymphony.xwork.Action; Ik G&
5'%I4@Qn+
/** K`*GZ+b|`
* @author Joa r924!zdbR
*/ %L|fTndKH
publicclass ListUser implementsAction{ HR>Y?B{
l.YE@EL
privatestaticfinal Log logger = LogFactory.getLog fHt \KP
'K[ml ?_
(ListUser.class); oqrx7+0{
V^~RDOSy7n
private UserService userService; g?j)p y
FaHOutP
private Page page; =~^b
=?sG~
privateList users; /\J0)V
@!ChPl
/* c-Gp|.C
* (non-Javadoc) gF6> /
* 0b&