Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 k
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #rz!d/)Q
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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 9m"EY@-
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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 kexvE 3
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分页支持类: r. rzU
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java代码: >@-BZJg/k
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package com.javaeye.common.util; x.I?)x!C'
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import java.util.List; DoN]v
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publicclass PaginationSupport { u0Z MrIJ
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publicfinalstaticint PAGESIZE = 30; je%y9*V
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privateint pageSize = PAGESIZE; QZL,zI]LL
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privateList items; SK@lr
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privateint totalCount; 1:{+{Yl7
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privateint[] indexes = newint[0]; jS#YqVuN
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privateint startIndex = 0; aCfWbJ@qiG
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public PaginationSupport(List items, int ?'tFTh
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totalCount){ vXak5iq>X
setPageSize(PAGESIZE); {s2eOL5I|%
setTotalCount(totalCount); I3ugBLxVC3
setItems(items); iqWkhJphv
setStartIndex(0); !|J2o8g
} J!QIMA4{
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public PaginationSupport(List items, int btDTC9O
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bu2;
totalCount, int startIndex){ )L"J?wTe
setPageSize(PAGESIZE); qE6D"+1y7
setTotalCount(totalCount); Z|3[Y@c\
setItems(items); {{ 1qkG9$
setStartIndex(startIndex); oRmA\R*
} GIS,EwA
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public PaginationSupport(List items, int #1'p?%K.
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totalCount, int pageSize, int startIndex){ J8&0l&~6
setPageSize(pageSize); EgOiJH
setTotalCount(totalCount); ~UwqQD1p
setItems(items); }fhGofN$e
setStartIndex(startIndex); BMn`t@ !x
} , LqfwA|
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publicList getItems(){ @~i :8
return items; Yg;7TKy
} ;;432^jD
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publicvoid setItems(List items){ ,jy9\n*<t9
this.items = items; Q_k'7Z\g$
} Z v 7}C
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publicint getPageSize(){ zpcO7AY~
return pageSize; @|d`n\%x
} IL%P\Zs
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publicvoid setPageSize(int pageSize){ d @b ]/
this.pageSize = pageSize; e,*@+E\4
} aL8Z|*
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publicint getTotalCount(){ PD^Cj?wm
return totalCount; ztC,[
} 1E$^ul-v
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publicvoid setTotalCount(int totalCount){ "Q[?W(SA
if(totalCount > 0){ gjB(Pwx
this.totalCount = totalCount; @M(+YCi:e@
int count = totalCount / ~yY5pnJ
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pageSize; i~{ 0>"9
if(totalCount % pageSize > 0) 85:mh\@-G
count++; suN}6CI
indexes = newint[count]; uLt31G()
for(int i = 0; i < count; i++){ -]:1zU
indexes = pageSize * r
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i; O7f"8|=HX
} *3y_FTh8ra
}else{ 07vzVsQ}p
this.totalCount = 0; ?|GwuG8g
} 0)9n${P7d
} $$T a
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publicint[] getIndexes(){ "l(<<Ha/
return indexes; LiJ. /
} Gr~J-#a3~D
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publicvoid setIndexes(int[] indexes){ 8~iggwZ~h"
this.indexes = indexes; |#22pq?RP
} bKr73S9
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publicint getStartIndex(){ wHs4~"EY9
return startIndex; R1Q~UX]d=
} or[! C%
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publicvoid setStartIndex(int startIndex){ 41i#w;ojI
if(totalCount <= 0) OB+QVYk"
this.startIndex = 0; J/c5)IB|
elseif(startIndex >= totalCount) [h0)V(1KR
this.startIndex = indexes i(S}gH4*o
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[indexes.length - 1]; 3Io7!:+
elseif(startIndex < 0) =qww|B92
this.startIndex = 0; 9y;zk$O8
else{ &[[Hfs2:-]
this.startIndex = indexes r@G34QC+
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[startIndex / pageSize]; fczH^+mI
} !PEP`wEKdp
} JzkI!5c<j
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publicint getNextIndex(){ @[O|n)7
int nextIndex = getStartIndex() + P2
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pageSize; KK/siG~O
if(nextIndex >= totalCount) 2Jt*s$
return getStartIndex(); X>eFGCz}I
else 0G8zFe*p
return nextIndex; H|<Zm:.%$
} Yo,n#<37
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publicint getPreviousIndex(){ P A$jR
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int previousIndex = getStartIndex() - kp,$ NfD
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pageSize; Wtp;se@#
if(previousIndex < 0) W<Asr@
return0;
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else d-B,)$zE
return previousIndex; Z:>ek>Op
} @E?o~jO(e
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} #$,b )Uy
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抽象业务类 xDn#=%~+x
java代码: LbnW(wr6:(
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/** R rp-SR?O
* Created on 2005-7-12 A7zL\U4
*/ nZ#0L`@"Y
package com.javaeye.common.business; _O`s;oc
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import java.io.Serializable; P u,JR
import java.util.List; +?GsIp@>jh
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import org.hibernate.Criteria; byX)4&
import org.hibernate.HibernateException; e0`5PVJ
import org.hibernate.Session; Vv*](iM
import org.hibernate.criterion.DetachedCriteria; Z
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import org.hibernate.criterion.Projections; 1raq;^e9
import @gjA8mL
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org.springframework.orm.hibernate3.HibernateCallback; oN=>U"<\1
import bA/'IF+
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org.springframework.orm.hibernate3.support.HibernateDaoS 6Vu)
rWip[>^
upport; B[;aNyd<
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import com.javaeye.common.util.PaginationSupport; [(Ihu e
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public abstract class AbstractManager extends ZO]P9b
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HibernateDaoSupport { S.*LsrSV
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privateboolean cacheQueries = false; k6(0:/C
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privateString queryCacheRegion; v`r*Yok;`
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publicvoid setCacheQueries(boolean 4Xe8j55
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cacheQueries){ %ZGG6Xgw
this.cacheQueries = cacheQueries; C\}M_MD
} jXYjs8Iy
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publicvoid setQueryCacheRegion(String {EyWSf"
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queryCacheRegion){ B1b9
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this.queryCacheRegion = M,oRi;V
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queryCacheRegion; KDLrt
} 1i@a? 27|
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publicvoid save(finalObject entity){ \n^;r|J7k
getHibernateTemplate().save(entity); > QG@P
} pLtK :Z
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publicvoid persist(finalObject entity){ fY!9i5@'
getHibernateTemplate().save(entity); nt*K@
} c2:oM<6|
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publicvoid update(finalObject entity){ n {..Q,z
getHibernateTemplate().update(entity); G@scz!Nt
} FM<`\d'
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publicvoid delete(finalObject entity){ @oQ"FLF.
getHibernateTemplate().delete(entity); ;1q|SmF
} 6T%5<I*&3s
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publicObject load(finalClass entity, /?u]Fj
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finalSerializable id){ %\Mc6
return getHibernateTemplate().load &o'$uLF~Y
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(entity, id); ^#4Ah[:XA
} Oe lf^&m
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publicObject get(finalClass entity, +IG=|X
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finalSerializable id){ gB]jLe
return getHibernateTemplate().get [I}xR(a@n
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(entity, id); 'Ej+Jczzpp
} 3|bbJ6*.<
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publicList findAll(finalClass entity){ Hd_,`W@
return getHibernateTemplate().find("from 0e(4+:0
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" + entity.getName()); =A(Az
} XzPUll;ZU
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publicList findByNamedQuery(finalString )oy+-1dE
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namedQuery){ >{>X.I~
return getHibernateTemplate SZ~lCdWad
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().findByNamedQuery(namedQuery); )C0d*T0i
} s\0,@A
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publicList findByNamedQuery(finalString query, I?_WV_T&
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finalObject parameter){ Av!xI
return getHibernateTemplate |v_ttJ;+Y
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().findByNamedQuery(query, parameter); q2*1Gn9!j
} $J#Z`%B^y
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publicList findByNamedQuery(finalString query, hP$5>G(3
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finalObject[] parameters){ b"w@am>&
return getHibernateTemplate YmLpGqNv
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().findByNamedQuery(query, parameters); 12tk$FcY8*
} $4hi D;n
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publicList find(finalString query){ 0/uy'JvWru
return getHibernateTemplate().find /q)
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(query); #szIYyk
} oj@=Cq':-
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publicList find(finalString query, finalObject Tt4Q|"CJA
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parameter){ sK8sxy
return getHibernateTemplate().find :"cKxd
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(query, parameter); rA}mp]
} k+~2
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public PaginationSupport findPageByCriteria f6 s .xQ
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(final DetachedCriteria detachedCriteria){ hx ^ l
return findPageByCriteria Xh }G=1}
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); m@2=vq1f
} gZ8JfA_\R(
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public PaginationSupport findPageByCriteria +'_ peT.8
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(final DetachedCriteria detachedCriteria, finalint S3&n?\CO:
FsS.9
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startIndex){ *:ErZ UyQM
return findPageByCriteria )nrYxxN
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(detachedCriteria, PaginationSupport.PAGESIZE, rp|A88Q/!
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startIndex); q>.C5t'Qx
} LIT`~D
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public PaginationSupport findPageByCriteria >ByqM{?
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(final DetachedCriteria detachedCriteria, finalint RDEK=^J
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pageSize, u#NX`_
finalint startIndex){ 4j(`koX_
return(PaginationSupport) \i\>$'f*z
p3e=~{v*
getHibernateTemplate().execute(new HibernateCallback(){ ^tIYr<I
publicObject doInHibernate <k{_YRB
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(Session session)throws HibernateException { )TEod!]
Criteria criteria = t%Bh'HkG
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detachedCriteria.getExecutableCriteria(session); uPE Ab2u="
int totalCount = =sF4H_B
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als
((Integer) criteria.setProjection(Projections.rowCount f,ZJFb98
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()).uniqueResult()).intValue(); g |H
criteria.setProjection $k`j";8uR
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(null); Uyxn+j5
List items = ZrB(!L~7
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criteria.setFirstResult(startIndex).setMaxResults (p]S
rV} 5&N*c
(pageSize).list(); 2*a9mi
PaginationSupport ps = 3*\hGt,ZP
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new PaginationSupport(items, totalCount, pageSize, NE4]i
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startIndex); `I(ap{
return ps; |;&I$'i
} K(HrwH`a{
}, true); 'p@m`)Z
} )0g!lCfb
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public List findAllByCriteria(final y=Z[_L!xr
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DetachedCriteria detachedCriteria){ +\?+cXSc
return(List) getHibernateTemplate RxNLn/?d@
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().execute(new HibernateCallback(){ &3 Ki
publicObject doInHibernate ? cn`N|
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(Session session)throws HibernateException { 5\h 6'
Criteria criteria = yXqC
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detachedCriteria.getExecutableCriteria(session); J%T=FU
return criteria.list(); oTx>oM,
}
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}, true); C](djkA$
} pG'?>]Rt4
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public int getCountByCriteria(final Y*{5'q+2
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DetachedCriteria detachedCriteria){ S!b?pl
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ sB$" mJ
publicObject doInHibernate _!Pi+l4p/}
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(Session session)throws HibernateException { H328I}7
Criteria criteria = ivB,s5<
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detachedCriteria.getExecutableCriteria(session); )u4=k(
return 2%9L'-
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criteria.setProjection(Projections.rowCount $yq76
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()).uniqueResult(); #_UP}G$
} *ae)<l3v
}, true); lY2~{Y|4s
return count.intValue(); u J]uz%
} GG-b)64h`
} 06Q9X!xD
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用户在web层构造查询条件detachedCriteria,和可选的 Y3s8@0b3
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (`4&Y-
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PaginationSupport的实例ps。 xg 8R>j
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ps.getItems()得到已分页好的结果集 qnnRS
ps.getIndexes()得到分页索引的数组 94|ZY}8|f
ps.getTotalCount()得到总结果数 W]_a_5
ps.getStartIndex()当前分页索引
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ps.getNextIndex()下一页索引 l*huKSX}
ps.getPreviousIndex()上一页索引 NU+PG`Vb
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 MPn/"Fij$
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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 J!G92A~*]
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一下代码重构了。 MgN;[4|[h
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我把原本我的做法也提供出来供大家讨论吧: _[i.)8$7
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首先,为了实现分页查询,我封装了一个Page类: ' o*\N%
java代码: q/Ji}NGm
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/*Created on 2005-4-14*/ 'tcve2Tt
package org.flyware.util.page; zAvI f
@<X[,Mj
/** ,fN <I
* @author Joa 6@3v+Vf'
* !!8;ZcL}Z
*/ ZX.,<vumSy
publicclass Page { g& f)WQ(
|1/8m/2Af.
/** imply if the page has previous page */ Aq7`A^1t$
privateboolean hasPrePage; )OucJQ
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/** imply if the page has next page */ "u&7Y:)^wr
privateboolean hasNextPage; mG\9Qkom|
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/** the number of every page */ Z_<NUPE
privateint everyPage; +2}Ar<elP
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/** the total page number */ `ZO5-E
privateint totalPage; i,%N#
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/** the number of current page */ 2
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privateint currentPage; ^k{/Yl
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/** the begin index of the records by the current i_+e&Bjd4j
vRD(* S9^
query */ VS>hi~j
privateint beginIndex; Ov4 [gHy&
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/** The default constructor */ H 8 66,]
public Page(){ e=IbEm{|
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} 'J!Gip ,
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/** construct the page by everyPage )8n?.keq
* @param everyPage w40*vBz
* */ B|+%ExT7
public Page(int everyPage){ ;~WoJlEK3
this.everyPage = everyPage; B#.xs>{N
} H4{7,n
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/** The whole constructor */ LWSy"Cs*
public Page(boolean hasPrePage, boolean hasNextPage, 3m2y<l<
dl |$pm@x
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int everyPage, int totalPage, s|Vs#o.P)
int currentPage, int beginIndex){ dVGcth;
this.hasPrePage = hasPrePage; Z=%u:K}[
this.hasNextPage = hasNextPage; '%:E4oI
this.everyPage = everyPage; 1rU\ !GfR
this.totalPage = totalPage; B6\/xKmv?8
this.currentPage = currentPage; AXi4{Q,
this.beginIndex = beginIndex; m7XN6zX
} cXN0D\%`
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/** ;A*sub
* @return .>PwbZ
* Returns the beginIndex. jv1p'qs4
*/ K@!hrye
publicint getBeginIndex(){ <5CQ#^cK
return beginIndex; F8{T/YhZ
} @T.F/Pjhc
8JW0;H<
/** J4iu8_eH!D
* @param beginIndex <Nc9F['
* The beginIndex to set. *laFG<;
*/ 3O2vY1Y2
publicvoid setBeginIndex(int beginIndex){ 99]s/KD2yb
this.beginIndex = beginIndex; KVViTpZ
} ^{++h?cS)
a{%EHL,F
/** U~c9PqjZ
* @return R iV]SgV9
* Returns the currentPage. _+}hId
*/ G4#Yz6O
publicint getCurrentPage(){ /^&$ma\
return currentPage; /jq"r-S"
} irjHPuhcG
y] Cx[
/** ]#q$i[Y
* @param currentPage Aqg$q* Y
* The currentPage to set. ?9 `T_,
*/ a<+Rw{
publicvoid setCurrentPage(int currentPage){ Ml+f3#HP
this.currentPage = currentPage; cmaha%3d
} CaoQPb*
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/** ]Rp<64I o
* @return v{\~>1J{
* Returns the everyPage. |Z Cv>8?n
*/ /\1Q
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publicint getEveryPage(){ "e29j'u!*
return everyPage; OU mZ|
} Tilr%D(Q
+OB&PE
/** Q-U,1b
* @param everyPage L9whgXD
* The everyPage to set. ~IQjQz?
*/ +,D82V7S
publicvoid setEveryPage(int everyPage){ }ASBP:c"t
this.everyPage = everyPage; do%.KIk
} % %2~%FVb
u/\Ipk/
/** otP2qAI
* @return )S_%Ip
* Returns the hasNextPage. )MX%DQw
*/ x}reeqn
publicboolean getHasNextPage(){ Ja@?.gW
return hasNextPage; C|QJQ@bj0
} :+ "JPF4X
A+3=OBpkW0
/** rj5)b:c}
* @param hasNextPage h 'is#X 6:
* The hasNextPage to set. ^AUQsRA7PZ
*/ FOcDBCrOe
publicvoid setHasNextPage(boolean hasNextPage){ ab 6D &
this.hasNextPage = hasNextPage; Mq6_Q07
} `]Vn[^?D
EkN>5).
/** gJzS,g1]
* @return i\MW'b
* Returns the hasPrePage. W*4!A\K
*/ er !+QD,EM
publicboolean getHasPrePage(){ 7G_lGV_
return hasPrePage; Aca?C
} {Z[kvXf"mZ
):Ekf2
/** s: MJ{r(s
* @param hasPrePage $5>x)jr:w+
* The hasPrePage to set. ,z0E2
*/ :!,.c$M
publicvoid setHasPrePage(boolean hasPrePage){ 81wmKqDEs
this.hasPrePage = hasPrePage; eA/}$.R
} a6op
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/** WxF@'kdn*,
* @return Returns the totalPage. T9'5V@
* )#Y:Bj7H@2
*/ .q$/#hN:e
publicint getTotalPage(){ %E2C4UbY
return totalPage; 89A04HX
} ?Ye%k
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/** sF#t{x/sW
* @param totalPage ;!>>C0s"
* The totalPage to set. /3~}= b
*/ sZU
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publicvoid setTotalPage(int totalPage){ tLx8}@X"
this.totalPage = totalPage; h6(L22Hn
} .O.fD
QOF'SEq"k
} E__A1j*gd
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hM`*-+Zb
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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 C6b(\#g(
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个PageUtil,负责对Page对象进行构造: _Hq)mF
java代码: N;e*eMFE
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/*Created on 2005-4-14*/ . J*2J(T,
package org.flyware.util.page; N" oJ3-~
%] 7.E
import org.apache.commons.logging.Log; ^KFwO=I@PV
import org.apache.commons.logging.LogFactory; HC ?XNR&
2O9OEZdKB
/** i{ /nHrN
* @author Joa woK?td|/
* HLM"dmI
*/ = G3A}
publicclass PageUtil { y|Zj
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privatestaticfinal Log logger = LogFactory.getLog <i1P ~
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8
(PageUtil.class); [x|{VJ(h
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/** r.zJ/Tk
* Use the origin page to create a new page OAz-w
* @param page h%@#jvh?4
* @param totalRecords vweD{\b
* @return n?A;'\cK
*/
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publicstatic Page createPage(Page page, int R0mWVgoz
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totalRecords){ "'"dcA
return createPage(page.getEveryPage(), #/`V.jXt>
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page.getCurrentPage(), totalRecords); bpeWK&
} _Msaub!N
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/** bga2{<VF
* the basic page utils not including exception m,]M_y\u
b%,`;hy{
handler -f:uNF]Ls
* @param everyPage l=JK+uZ
* @param currentPage Zx]"2U#
* @param totalRecords :!Tb/1
* @return page v4Q8RE?
*/ {z}OZHJN
publicstatic Page createPage(int everyPage, int >j$CM:w
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currentPage, int totalRecords){ g @lAk%V4
everyPage = getEveryPage(everyPage); =>6'{32W_
currentPage = getCurrentPage(currentPage); FeFH_
int beginIndex = getBeginIndex(everyPage, #VEHyz 6P
I2'UC)
0
currentPage); _sCpyu
int totalPage = getTotalPage(everyPage, 2xd G&}$fa
SSF4P&
totalRecords); Wz7jB6AWA
boolean hasNextPage = hasNextPage(currentPage, D?Q{&6p
W7"ks(
totalPage); oFV>b
boolean hasPrePage = hasPrePage(currentPage); )/9/p17:xu
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returnnew Page(hasPrePage, hasNextPage, I(Yyg,1Z
everyPage, totalPage, kSw.Q2ao
currentPage, ~dK)U*Q
IPnbR)[%
beginIndex); OsR4oT
} fW4N+2
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privatestaticint getEveryPage(int everyPage){ [?hc.COE
return everyPage == 0 ? 10 : everyPage; /^\6q"'
} ;[@<
,
5!G}*u.
privatestaticint getCurrentPage(int currentPage){ Ij }RlYQz
return currentPage == 0 ? 1 : currentPage; ~$i36"
} 70:a2m
?c^0%Op
privatestaticint getBeginIndex(int everyPage, int 2@aVoqrq#
K/jC>4/c/
currentPage){ {@oYMO~
return(currentPage - 1) * everyPage; kGMI
?
} 7PZ0
rr#&0`]
privatestaticint getTotalPage(int everyPage, int Khxl'qj
ALiXT8q
totalRecords){ \5Jpr'mY5
int totalPage = 0; DxT8;`I%
gX34'<Z
if(totalRecords % everyPage == 0) n-{G19?
totalPage = totalRecords / everyPage; p/xxoU
else snV,rZ
totalPage = totalRecords / everyPage + 1 ; s7<x~v+^
FHI`/
return totalPage; g#1_`gK
} Jn.WbS
PK5xnT:
privatestaticboolean hasPrePage(int currentPage){ w7]@QTC
return currentPage == 1 ? false : true; Z!m0nx
} [=-?n6
~fE@]~f>
privatestaticboolean hasNextPage(int currentPage, _d&FB~=
wg*2mo
int totalPage){ },'2j
return currentPage == totalPage || totalPage == hof:+aW
ajW[}/)
0 ? false : true; 0*q&)
} c?CjJ}-7
9Ay*'
5~ CHj
} 0I4RZ.2*Y
a="Z]JGk
!~cTe!T
C9U~lcIS
*S_eYKSl
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Dg4?,{c9W
rm NqS+t
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 !h{qO&ZH=
2`Xy}9N/Y
做法如下: z)r)w?A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 bH&Cbme90-
#m6 eG&a
的信息,和一个结果集List: _U)DL=a'
java代码: INsc!xOQ
e;56}w
E/9 U0
/*Created on 2005-6-13*/ _pM&Ya
package com.adt.bo; C$xU!9K[+
_gjsAbM
import java.util.List; cTFyF)
rE-Xv.
|
import org.flyware.util.page.Page; CEE`nn
;Id%{1
/** ;-47d ^
* @author Joa 69 R8#M
*/ :Q=Jn?Gjb
publicclass Result { 1GVJ3VXt
Q d]5e
private Page page; ;$=`BI)
Jeyy Z=
private List content; /+ vl({vV
7$+n"Cfm
/** TGGeTtk=
* The default constructor j8!fzJG
*/ [L8Bgw1
public Result(){ _K>cB<+d
super(); 1"009/|
} cpp0Y^
xCD|UC46?X
/** [ XjJsk,
* The constructor using fields <*~vZT i(
* MVK='
* @param page NA>h$N
* @param content R 28v5
*/ s!``OyI/Z
public Result(Page page, List content){ ZJ@M}-4O1
this.page = page; #[C|%uq
this.content = content; 8l0%:6XbI
} gd-4hR
s(J,TS#I]
/** B0NKav
* @return Returns the content. ZkkXITQkPM
*/ @kn0f`
publicList getContent(){ ^)conSm
return content; 5V4Ze;K
} |AW[4Yn>
P*XLm
/** K_',Gd4L
* @return Returns the page. V6?ku6k
*/ $%"i|KTsv:
public Page getPage(){ 1 e1$x@\\
return page; IL?3>$,
} gYfN?A*`_
v_"p)4&'
/** 8MGtJ'.
* @param content {3]g3mj
* The content to set. hWwh`Vw%
*/ 1+v&SU
public void setContent(List content){ *<#jr
this.content = content; 4:=']C
} h}i
/u
Pfu2=2Ra
/** MQY^#N
* @param page L"A,7@:Vd
* The page to set. g8
,V( ^
*/ RyKsM.
publicvoid setPage(Page page){ kXA
o+l
this.page = page; aErms-~
} 4<)%Esyb
} b"t95qlL
: I28Zi*
ao#{N=mn
s\,F6c
qP6]}Aj]
2. 编写业务逻辑接口,并实现它(UserManager, a H'iW)
QpwOrxI}
UserManagerImpl) t/LQ|/xo
java代码: fGHYs
EFu2&P
&WE| 9
/*Created on 2005-7-15*/ vF0#]
package com.adt.service; k`U")lv
xGCW-YR9
import net.sf.hibernate.HibernateException; 3~}G~ t
pw"
!iG}
import org.flyware.util.page.Page; M.))UKSF
mufi>}
import com.adt.bo.Result; @|v4B[/
<61T)7
/** Vrzx;V%
* @author Joa eTemRNz
*/ n~l9`4wJY
publicinterface UserManager { 9&fS<Hk
0m7ANqE[Z
public Result listUser(Page page)throws 9{@[l!]W
zD:"O4ZM^^
HibernateException; O-y/K2MC*
qZACX.Hw
} Mh"DPt9@J
%yX?4T;b
'd 4I/
losm<
[ Hw
java代码: rXc-V},az8
L|.q19b*
5wYYYo=
/*Created on 2005-7-15*/ ~A2{$C
package com.adt.service.impl; \B) a57
mIgc)"
import java.util.List; +>h}Uz
B/.+&AJw
import net.sf.hibernate.HibernateException; *F0O*n*7W
g*?)o!_*
import org.flyware.util.page.Page; S7]\tw_L)
import org.flyware.util.page.PageUtil; )zz^RB\p
H6%QM}t
import com.adt.bo.Result; =NLsT.aa
import com.adt.dao.UserDAO; yH5^EY7rQ
import com.adt.exception.ObjectNotFoundException; 5S`_q&
import com.adt.service.UserManager; XG FjqZr`
oU`8\n](
/** <"F\&M`G
* @author Joa qpzzk9ba[
*/ GSo&$T;B6
publicclass UserManagerImpl implements UserManager { l]t9*a]a
jN
9|q
private UserDAO userDAO; "&;8U.
n " ?It
/** FeOo;|a
* @param userDAO The userDAO to set. ,PC'xrEo
*/ XCr\Y`,Z@
publicvoid setUserDAO(UserDAO userDAO){ 81Ixs
Qt
this.userDAO = userDAO; 3SI:su
} h!.#r*vV
u"eO&Vc
/* (non-Javadoc) 8w1TX [b
* @see com.adt.service.UserManager#listUser &N4Jpa}w/%
zY_xJ"/9
(org.flyware.util.page.Page) "c5C0 pK0
*/ ZI.;7G@|
public Result listUser(Page page)throws ZS&>%G
f}{ lRk
HibernateException, ObjectNotFoundException { *FhD%><
int totalRecords = userDAO.getUserCount(); 0kC}qru'
if(totalRecords == 0) `q
= e<$
throw new ObjectNotFoundException {6H%4n
GP=i6I6C
("userNotExist"); #=@H-ZuD7
page = PageUtil.createPage(page, totalRecords); +/
s2;G
List users = userDAO.getUserByPage(page); qYpuo
D
returnnew Result(page, users); M]9oSi
} I#lvaoeN
YDh6XD<Z
} }xhat,9
5'iJN$7
Gt;@.jY&
oVi_X98R
2y6@:VxSh
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 =2+';Xk\
81?7u!=ic+
询,接下来编写UserDAO的代码: x~1.;dBF
3. UserDAO 和 UserDAOImpl: WOqAVd\
java代码: WZ}je!82
HqM>K*XKU
~yacJU=
/*Created on 2005-7-15*/ rb8c^u#r
package com.adt.dao; ]MI>"hn
&?+ vHE}
import java.util.List; ifA=qn0=}
X3nt*G1dL
import org.flyware.util.page.Page; Bfh[C]yy
b-Fv
vA
import net.sf.hibernate.HibernateException; tF:'Y ~3 p
J6m`XC
/** -anLp8G*
* @author Joa 'p0|wM_
*/ Y)D~@|D,
publicinterface UserDAO extends BaseDAO { `v2]Jk<
4a'O#;ho
publicList getUserByName(String name)throws 9iMQq40
?Q$LIoR
HibernateException; /48W]a}JS
2 uuI_9 "^
publicint getUserCount()throws HibernateException; >y
P`8Oq[
2kv%k3Q{
publicList getUserByPage(Page page)throws kk`BwRh)d;
, $;g'z!N
HibernateException; m]g"]U:
_W@SCV)yH
} dU!`aPL?
3,`.$
,.#
SEv5
JGmW>mH
9C$#A +~C
java代码: `b(y 5 Z
!8 3x,*O
79.J`}#
/*Created on 2005-7-15*/ 5f54E|vD
package com.adt.dao.impl; 8mjP2
`i{k^Q
import java.util.List; e"jA#Y #
84PD`A
import org.flyware.util.page.Page; bYzBe\^3q3
c[=%v]j:u
import net.sf.hibernate.HibernateException; .aRL'1xHl
import net.sf.hibernate.Query; U3ygFW%
3J\NkaSR
import com.adt.dao.UserDAO; 6~ g:"}
7ko7)"N
/** *%0f^~!G<p
* @author Joa A<6V$e$:2
*/ d2H&@80
public class UserDAOImpl extends BaseDAOHibernateImpl 8ad!.
dhW; |
implements UserDAO { ~;ink
Ru%:
z>Y
/* (non-Javadoc) K;2]c3T
* @see com.adt.dao.UserDAO#getUserByName IBwquw+
0m5Q;|mH
(java.lang.String) -25#Vh
*/ +uPN+CgQ@
publicList getUserByName(String name)throws E(G=~>P
Fa(}:Ug
HibernateException { `I$qMw,@
String querySentence = "FROM user in class ;qI5GQ {
rT`D@
I
com.adt.po.User WHERE user.name=:name"; #vO3*-hs
Query query = getSession().createQuery o3H+.u$
Xco$
yF%
(querySentence); Tb-`0^y&X1
query.setParameter("name", name); =N,KVMxw
return query.list(); y)3(
} MDkIaz\U
}9C5U>?
/* (non-Javadoc) c%.f|/.k
* @see com.adt.dao.UserDAO#getUserCount() 9X&Xs/B
*/ >/"XX,3
publicint getUserCount()throws HibernateException { %EPqJ(T
int count = 0; ~qNpPIrGr
String querySentence = "SELECT count(*) FROM (l22p
YQR*?/?a
user in class com.adt.po.User"; RJs_ S
Query query = getSession().createQuery (4V1%0
SwQ.tK1p
(querySentence); <!,q:[ee5
count = ((Integer)query.iterate().next ,8(%J3J
_ED1".f
()).intValue(); (.,E6H|zI
return count; -
Pz
)O@ ;
} ^_<>o[qE
IidZ-Il
/* (non-Javadoc) u)P$xkf
* @see com.adt.dao.UserDAO#getUserByPage 3&*0n^g
rL URP2~
(org.flyware.util.page.Page) y? [*qnPj
*/ F~d
!Ub$>
publicList getUserByPage(Page page)throws Zn3iLAPBX
QnxkD)f*0
HibernateException { gb:Cc,F,%
String querySentence = "FROM user in class K/[v>(<
4~a0
com.adt.po.User"; o,) p *glO
Query query = getSession().createQuery *9^CgLF
f/)3b`$Wu
(querySentence); Pi?*rr5WZ
query.setFirstResult(page.getBeginIndex()) KGUpXMd^Z
.setMaxResults(page.getEveryPage()); v >3ctP{
return query.list(); rOY^w9!
} 7>{edNy!,
#},]`"n\
} qn@Qd9Sf
K! /E0G&
./<3jf :
HkvCQ H
c7\bA7.
至此,一个完整的分页程序完成。前台的只需要调用 ^OG^%
x"
@n(=#Q3
userManager.listUser(page)即可得到一个Page对象和结果集对象 mUy/lo'4
cXJgdBwo
的综合体,而传入的参数page对象则可以由前台传入,如果用 jn\\,n"6
JXj`
webwork,甚至可以直接在配置文件中指定。 ^
+{ ~
^y7
xSb/98;
下面给出一个webwork调用示例: ?p5RSt
java代码: u\qyh9s
fJv0 B*
%8o(x 0
/*Created on 2005-6-17*/ QBto$!})
package com.adt.action.user; 3|:uIoR{
Op3 IL/
import java.util.List; |ry;'[*
U7crbj;c)d
import org.apache.commons.logging.Log; any\}
import org.apache.commons.logging.LogFactory; O8u"Y0$*w
import org.flyware.util.page.Page; 2|}p&~G(
8Z3+S)6
import com.adt.bo.Result; y8+?:=N.
import com.adt.service.UserService; lRt8{GFy
import com.opensymphony.xwork.Action; ^Hq}9OyS9
kq%`9,XE
/** 6}NvVolr
* @author Joa FA{I
S0
*/ uy\YJ.WMQ
publicclass ListUser implementsAction{ [9?=&O#*
{OAy@6
+
privatestaticfinal Log logger = LogFactory.getLog f| N(~
}Tc)M_
(ListUser.class); `"ie57-
A94VSUDA:
private UserService userService; .h+<m7
zm8m J2s
private Page page; cjN4U [
n;rOH[P
privateList users; uaDU+ywL
R&xD|w8UjM
/* I:6xDDpZG`
* (non-Javadoc) rW\~s TH
* DBmcvC
* @see com.opensymphony.xwork.Action#execute() =D[h0U
*/ !d(!1fC
publicString execute()throwsException{ n@mUQ6
Result result = userService.listUser(page); &H4UVI
page = result.getPage(); xBw"RCBz^
users = result.getContent(); }p- %~Y
return SUCCESS; Rkm7"dO0
} ^d=Z/d[
!m(6/*PAl
/** 0N
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* @return Returns the page. r*p%e\ 3
*/ e@,L~\
public Page getPage(){ moo>~F _^
return page; (u'/tNGS
} #ASu
SQ
mMjVbeh[
/** 73<iK]*c
* @return Returns the users. ;q^YDZ'
*/ ah<f&2f
publicList getUsers(){ Rw\DJJrz
return users; ^X;>?_Bk
} *{Z!m@?
(CV=0{]
/** 9E#(i P
* @param page QV 'y6m\
* The page to set. a #0{tZd
*/ hBqu,A
publicvoid setPage(Page page){ 0,3 ':Df
this.page = page; O71rLk;
} *oWzH_
Ce)Wvuh
/** ixH7oWH#
* @param users uJ y@
* The users to set. p}!pT/KmpH
*/ R 1 b`(
publicvoid setUsers(List users){ HWU{521
this.users = users; k %rP*b*
} 1M{#"t{6
N|)V/no 6
/** gjWH
}(K
* @param userService W P&zF$
* The userService to set. f:0n-me
*/ E,$uNw ']
publicvoid setUserService(UserService userService){ fh3
6
this.userService = userService; l85"C
}
'ng/A4
} od fu7P_
iTvCkb48m
\*
#4
qprOxP
r
gA|j\T{c
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, O gnpzN
ZM.g+-9
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 K\ ]r
R}Y=!qjYE=
么只需要: !R@4tSu
java代码: pp`U]Q5"gX
A%O#S<sa
jY.%~Y1y
<?xml version="1.0"?> 5b'S~Qj#r$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork J"MJVMo$T
*)1z-rH`
1.0//EN" "http://www.opensymphony.com/xwork/xwork- xL"%2nf
2Qj)@&zKe#
1.0.dtd">
}+J@;:
2cl~Va=
<xwork> QAwj]_
do,X{\
<package name="user" extends="webwork- y|se^dn
}"Cn kg
interceptors"> U*TN/6Qy.
-EaZ<d[|0
<!-- The default interceptor stack name (c2\:hvy
eV0S:mit
--> bl<7[J.
<default-interceptor-ref 5aNDW'z`f
lz 6 Aj
name="myDefaultWebStack"/> Qg!*=<b
Q^rW^d
<action name="listUser" #O+]ydvT
tW>R 16zq
class="com.adt.action.user.ListUser"> E=NY{| >
<param ~S!kn1&O
!?/bK[
P,
name="page.everyPage">10</param> uek3Y[n
<result NN'<-0~
|lwN!KVQ,
name="success">/user/user_list.jsp</result> uLljM{I
</action> nj`qV
ew$Z5N:
</package> :,,y63-f4
8-ssiiJ}gh
</xwork> hp4(f W
pH%c7X/[3L
v6\2mc.
rC `s;w
|l(lrJ{
8]\h^k4f
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 eE%yo3
m0\}Cc
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 @ -d4kg
[frD
L)
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 #%"TU,[+
ZMg9Qt
F|`B2Gr
E]?HCRa5R
^3o8F
我写的一个用于分页的类,用了泛型了,hoho ldvxYq<:
L"6/"L
java代码: mm<iT59
G%jJ>T4
0]W]#X4A
package com.intokr.util; Y'0?<_ fj
fZ:rz;tM
import java.util.List; igj@{FN
v^_]W3K
/** S_VncTIO
* 用于分页的类<br> 59BHGvaF
* 可以用于传递查询的结果也可以用于传送查询的参数<br> T8TsKjqOZ
* ^GaPpm
* @version 0.01 6 Ok=q:;
* @author cheng V?dK *8s
*/ H6S vU
public class Paginator<E> { 7h&`BS
privateint count = 0; // 总记录数 V^/^OR4k
privateint p = 1; // 页编号 p<fgUVR
privateint num = 20; // 每页的记录数 Xb:BIp!e
privateList<E> results = null; // 结果 h]DECd{
=&:f+!1$
/** maEpT43f
* 结果总数 y{I[}$k
*/ %<#3_}"T|
publicint getCount(){ SJc@iffS
return count; bok 74U]
} lF"(|n"R
EQOP?>mWx!
publicvoid setCount(int count){ [67E5rk-
this.count = count; -hFyqIJW
} LI;Efy L
{%~4RZA
/** _AB9BQm
* 本结果所在的页码,从1开始 n.XhK_6n]M
* KPd C9H
* @return Returns the pageNo. /j69NEl
*/ ^8l3j4
publicint getP(){ OC>_=i$'
return p; fQy
C6C
} h k!,
BS,5W]ervE
/** PWN'.HQ
* if(p<=0) p=1 ]F*a PV
* hn\Q6f+
* @param p zP h\3B
*/ Q$h:[_v
publicvoid setP(int p){ SM /ykk
if(p <= 0) 'bI ~61{A
p = 1; @-&(TRbZo
this.p = p; o|;eMO-
} Am4^v?q
L}jF#*Q%
/** N>pmhskN?
* 每页记录数量 c6Aut`dK
*/ oAZF3h]po
publicint getNum(){ ]dbSa1?
return num; ){
} Z 5)_B,E:X
c@ZS|U*(
/** qQxA@kdd
* if(num<1) num=1 O%JsUKV
*/ =0PRAc
publicvoid setNum(int num){ .-KtB(t
if(num < 1) p>:ef<.i
num = 1; &`yOIX-H_
this.num = num; W[>iJJwz
} 5Z9 ~
&U
! FR%QGn1
/** /$9BPjO{
* 获得总页数 JS/M~8+Et
*/ {+"g':><
publicint getPageNum(){ C1T=O
return(count - 1) / num + 1; -.{oqs$
} wMz-U- z
OpK.Lsd0y
/** \6lh `U
* 获得本页的开始编号,为 (p-1)*num+1 dCZ\ S91q
*/ a(@p0YpKT
publicint getStart(){ /Fe:h>6
return(p - 1) * num + 1; h@~:(:zU$
} WGh. ;-
(S
k#x
/** 6X7s 4
* @return Returns the results. ,M)k7t:
*/ T~%H%O(F
publicList<E> getResults(){ Mny'9hsl
return results; #M5_em4kN
} I#U>5"%\a
J]}FC{CD!
public void setResults(List<E> results){ rQ
this.results = results; =n-z;/NL
} }xDB ~k
&:V@2_6"
public String toString(){ P_p6GT:5
StringBuilder buff = new StringBuilder P</s)"@
8F zHNG
(); e,f ;
buff.append("{"); >dpbCPJ9[
buff.append("count:").append(count); iOT)0@f'
buff.append(",p:").append(p); O)`fvpVU
buff.append(",nump:").append(num); YC]PN5[1!
buff.append(",results:").append i`prv&
Yd'H+r5b
(results); 07x=`7hs}
buff.append("}"); _QR
g7
return buff.toString(); \bhOPK>w
} 1~%o}+#-
GR,J0LT
} NSw<t9Yi
Bvz62?
K~c^*;F