Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 cdfll+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 kCwTv:)
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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 7IHD?pnZ
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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 j0%0yb{-^
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分页支持类: O\LW
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java代码: &S3W/lQs
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package com.javaeye.common.util; xk*3,J6BK
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import java.util.List; ^i8I 1@ =
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publicclass PaginationSupport { 8@fDn(]w
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publicfinalstaticint PAGESIZE = 30; Me}TW!GC
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privateint pageSize = PAGESIZE; PD}R7[".>
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privateList items; %)/f; T6
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privateint totalCount; Hr+-ndH!Pq
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privateint[] indexes = newint[0]; `es($7}P_W
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privateint startIndex = 0; p-pw*wH0
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public PaginationSupport(List items, int #8z,'~\
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totalCount){ 2&Byq
setPageSize(PAGESIZE); R2$ U K
setTotalCount(totalCount); ,OKM\N,
setItems(items); yo*iv+l
setStartIndex(0); /,Rca1W
} }K>HS\e
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public PaginationSupport(List items, int Qsntf.fT
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totalCount, int startIndex){ 99 !{[gOv
setPageSize(PAGESIZE); 3] qlz?5
setTotalCount(totalCount); '!-?
setItems(items); fl"y@;;#h
setStartIndex(startIndex); 9 <KtI7
} O$Vm#|$sq
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public PaginationSupport(List items, int x}.d`=
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totalCount, int pageSize, int startIndex){ 5ZA%,pH>Jq
setPageSize(pageSize); PEBFN
setTotalCount(totalCount); ?nZ <?
setItems(items); Z% ;4Ed
setStartIndex(startIndex); >'6GcnEb4.
} 7I(t,AKJ
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publicList getItems(){ aE BP9RX}z
return items; p{a]pG+3
} v1C.\fL
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publicvoid setItems(List items){ T'M66kg
this.items = items; Q==v!"Gi|
} jAK{<7v4U
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publicint getPageSize(){ AD@PNM
return pageSize; u7"VeTz
} Tj=dL
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publicvoid setPageSize(int pageSize){ HqdJdWl#"
this.pageSize = pageSize; wz+5
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} d_C4B
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publicint getTotalCount(){ ^
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return totalCount; dPx<Dz;
} ?Y{^un
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publicvoid setTotalCount(int totalCount){ ~u0xXfv#
if(totalCount > 0){ A,gx5!J
this.totalCount = totalCount; }{8Fo4/
int count = totalCount / cH;TnuX
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pageSize; YvruK:I
if(totalCount % pageSize > 0) `OP>(bU0
count++; lB!vF ~A&
indexes = newint[count]; 6B''9V:s
for(int i = 0; i < count; i++){ PDIclIMS'F
indexes = pageSize * m*!f%}T
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i; k=7Gr;;l=p
} C,r`I/;
}else{ /u)Rppu
this.totalCount = 0; :B=8_M
} NGD*ce"w
} 0HR|aqPo
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publicint[] getIndexes(){ gKN}Of@^1
return indexes; L"foL
} XY{:tR_al
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publicvoid setIndexes(int[] indexes){ )_8}53C
this.indexes = indexes; S9p?*
} h `ME(U~<<
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publicint getStartIndex(){ 9&%#nN4`8
return startIndex; [8@kx Cq
} i
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publicvoid setStartIndex(int startIndex){ iS1Gb$?
if(totalCount <= 0) *q*HG W5
this.startIndex = 0; nG"n-$A?<
elseif(startIndex >= totalCount) !&`}]qQZ
this.startIndex = indexes "#pzZ)Zh
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[indexes.length - 1]; S= -M3fP~
elseif(startIndex < 0) V5a?=vK9
this.startIndex = 0; sS2_-X[_
else{ vUYJf99B
this.startIndex = indexes H#L#2M%
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[startIndex / pageSize]; 8geek$FY x
} 2QGMe}
} A XBkJ'jd
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publicint getNextIndex(){ BWUt{,?KU
int nextIndex = getStartIndex() + dTN$y\
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pageSize; u#+RUtM
if(nextIndex >= totalCount) gg-};0P-
return getStartIndex(); ?MC(}dF0
else Xsd$*F@<
return nextIndex; \+k, :8s/
} r<*O
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publicint getPreviousIndex(){ 6F`qi:a+
int previousIndex = getStartIndex() - #JA}LA"l
pe()f/Jx(
pageSize; 2{ o0@
if(previousIndex < 0) [ -ISR7D
return0; LJGJ|P
else r C_d$Jv
return previousIndex; hq<5lE^
} ,+tPRkwA^
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} HU &)
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抽象业务类 AnNPTi
java代码: Y4#y34We
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/** )Zas
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* Created on 2005-7-12 vsKl#R B
*/ vwKw?Z0%J
package com.javaeye.common.business; [O2h-`
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import java.io.Serializable; ./l|8o
import java.util.List; .APVjqG
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import org.hibernate.Criteria; (w+%=z"M
import org.hibernate.HibernateException; I:#Ok+
import org.hibernate.Session; :pwa{P
import org.hibernate.criterion.DetachedCriteria; |;P^clS3
import org.hibernate.criterion.Projections;
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import '61i2\[lZQ
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org.springframework.orm.hibernate3.HibernateCallback; u4YM^* S.
import &Yp+k}XU
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org.springframework.orm.hibernate3.support.HibernateDaoS <_9!
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upport; 6xHi\L
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import com.javaeye.common.util.PaginationSupport; `(!NYx
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public abstract class AbstractManager extends *>k!hq;j
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HibernateDaoSupport {
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privateboolean cacheQueries = false; lEHwZ<je
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privateString queryCacheRegion; [Tb\woU
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publicvoid setCacheQueries(boolean -#aZF2z
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cacheQueries){ O)uOUB
this.cacheQueries = cacheQueries; 66Gx.tE
} (SF1y/g@=
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publicvoid setQueryCacheRegion(String R2 lXTW*
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queryCacheRegion){ tMFsA`ng
this.queryCacheRegion = &~#iIk~%
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queryCacheRegion; Vclr2]eV4O
} =_
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publicvoid save(finalObject entity){ M)JADX
getHibernateTemplate().save(entity); +I52EXo
} Vl<9=f7[
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publicvoid persist(finalObject entity){ H4:ZTl_$
getHibernateTemplate().save(entity); QR"bYQ
} 6NX3"i0eT
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publicvoid update(finalObject entity){ b`CWp;6Y
getHibernateTemplate().update(entity); q[ULGv
} .:y5U}vR
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); :)IV!_>'d
} (a.1M8v+Sg
cy|%sf`
publicObject load(finalClass entity, SfW}"#L>5
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finalSerializable id){ jl}$HEI5m}
return getHibernateTemplate().load ]JjK#eh
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(entity, id); J02^i5l
} Es.nHN^]%K
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publicObject get(finalClass entity, J}TfRrf
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finalSerializable id){ J8<J8x4
return getHibernateTemplate().get _D,eyP9P
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(entity, id); y-B=W]E
} +=eR%|!@
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publicList findAll(finalClass entity){ +Ok%e.\ZM
return getHibernateTemplate().find("from 6|!NLwa
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" + entity.getName()); XE rUS80
} |g-b8+.=]
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publicList findByNamedQuery(finalString $`ztiVu3
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namedQuery){ 8W+5)m.tp
return getHibernateTemplate K
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().findByNamedQuery(namedQuery); cozXb$bBY
} gU1 #`r>[)
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publicList findByNamedQuery(finalString query, :243 H
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finalObject parameter){ B,vOsa"x6`
return getHibernateTemplate :%X Ls,
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().findByNamedQuery(query, parameter); UE :HMn6
} [}2Z/
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publicList findByNamedQuery(finalString query, GABQUmtH
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finalObject[] parameters){ {fDTSr?/
return getHibernateTemplate vF4]ux&
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().findByNamedQuery(query, parameters); kV&9`c+
} aeP[+ I9
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publicList find(finalString query){ h#qN+qt}
return getHibernateTemplate().find +dW|^I{H}
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(query); UMMB0(0D
} `bG7"o`
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publicList find(finalString query, finalObject 9em*r9-
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parameter){ $uh z
return getHibernateTemplate().find 3
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(query, parameter); y\c"b-lQX
} ,Zf
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public PaginationSupport findPageByCriteria /rc%O*R
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(final DetachedCriteria detachedCriteria){ d8o53a]
return findPageByCriteria NHQF^2 \\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); mD58T2Z
} {b)~V3rsY
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public PaginationSupport findPageByCriteria 4QHS{tj
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(final DetachedCriteria detachedCriteria, finalint 'UU\4M
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startIndex){ HMGB>
return findPageByCriteria ,IHb+ K
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(detachedCriteria, PaginationSupport.PAGESIZE, 'LE"#2Hu
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startIndex); ,&^3Z
} iw9Q18:I}
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public PaginationSupport findPageByCriteria B4Y(?JTx
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(final DetachedCriteria detachedCriteria, finalint vH[47Cv G5
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pageSize, #qBr/+b
finalint startIndex){
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return(PaginationSupport) +IFw_3$
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getHibernateTemplate().execute(new HibernateCallback(){ #Pk$L+C
publicObject doInHibernate w'T q3-%V
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(Session session)throws HibernateException { 6xK[34~6
Criteria criteria = <Zb/
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detachedCriteria.getExecutableCriteria(session); O[^%{'
int totalCount = oqd;6[%G
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((Integer) criteria.setProjection(Projections.rowCount YwEpy(}hJm
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()).uniqueResult()).intValue(); yay<GP?
criteria.setProjection YZf6|
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(null); [Nm4sI11
List items = Sjj>#}U
"/Pjjb:2
criteria.setFirstResult(startIndex).setMaxResults =T?}Nt
/phX'xp
(pageSize).list(); -Apc$0ZsN
PaginationSupport ps = }L=/A7Nk>
{7hLsK[])
new PaginationSupport(items, totalCount, pageSize, OR1DYHHT/1
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startIndex); Vv.r8IGYm
return ps; :ue:QSt(u
} * |.0Myjo
}, true); `4?~nbz
} HSUI${<
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public List findAllByCriteria(final p9!"O
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DetachedCriteria detachedCriteria){ f"[J"j8
return(List) getHibernateTemplate c,MOv7{x_
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().execute(new HibernateCallback(){ Qd _6)M-
publicObject doInHibernate Kb#4ILA
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(Session session)throws HibernateException { :$;Fhf<5
Criteria criteria = a]17qMl
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detachedCriteria.getExecutableCriteria(session); gN8hJG'0
return criteria.list(); $,=6[T!z+e
} SvM6iZ]
}, true); !%+2Yifna
} jd]s<C3o
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public int getCountByCriteria(final aimarU
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DetachedCriteria detachedCriteria){ ,_aM`%q?Fj
Integer count = (Integer) {'sY|lou
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getHibernateTemplate().execute(new HibernateCallback(){ 1d"Z>k:mn
publicObject doInHibernate T3UMCqc=
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(Session session)throws HibernateException { @+vXMJ $
Criteria criteria = >WJf=F`_H
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detachedCriteria.getExecutableCriteria(session); (s<Dd2&.H
return ;7]u!Q
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criteria.setProjection(Projections.rowCount RpWTpT1
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()).uniqueResult(); Q)m4_+,d
} 0]KraLu"N
}, true);
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return count.intValue(); T{wpJ"F5<]
} n~"$^Vr
} q5h*`7f
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用户在web层构造查询条件detachedCriteria,和可选的 0nn okN^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 W>r#RXmh
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PaginationSupport的实例ps。 hT$~ygQ
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ps.getItems()得到已分页好的结果集 H9h@ sSg
ps.getIndexes()得到分页索引的数组 IEKU-k7}Z
ps.getTotalCount()得到总结果数 !TZhQiorC
ps.getStartIndex()当前分页索引 s+Fi @lg,
ps.getNextIndex()下一页索引 S(S#
ps.getPreviousIndex()上一页索引 /MY9
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 LmlXMia
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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 Y2xL>F
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一下代码重构了。 Um1[sMc{au
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我把原本我的做法也提供出来供大家讨论吧: a#mNE*Dg
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首先,为了实现分页查询,我封装了一个Page类: ,yd
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java代码: ]| N3eu
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:[ k4Z]t8
/*Created on 2005-4-14*/ +k
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package org.flyware.util.page; (P&4d~)m
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/** ?$f)&O
* @author Joa uwRr LF
* wi9DhVvc 0
*/ 0ye!R
publicclass Page { 4}`
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/** imply if the page has previous page */ (D@A74q\'
privateboolean hasPrePage; uB!kM
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/** imply if the page has next page */ jp $Z]
privateboolean hasNextPage; 763+uFx^
&/Ro lIHF
/** the number of every page */ K3\#E/Ox
privateint everyPage; gp$Ucfu'
2o>)7^9|#<
/** the total page number */ 83;NIE;
privateint totalPage; }FzqW*4~
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/** the number of current page */ ypJ".
privateint currentPage; p>_;^&>&
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/** the begin index of the records by the current JG9` h#
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query */ :4^\3~i1X
privateint beginIndex; P2nft2/eu?
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/** The default constructor */ M$0u1~K
public Page(){ -s 6![eV
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} L`th7d"
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/** construct the page by everyPage ,39aF*r1Q
* @param everyPage `R"I;qV
* */ #Rg|BfV-
public Page(int everyPage){ p{PE@KO:
this.everyPage = everyPage; BTM),
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} `/HUV&i"S
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/** The whole constructor */ 9;?UvOI;
public Page(boolean hasPrePage, boolean hasNextPage, 54rkC/B>
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int everyPage, int totalPage, a>mm+L8y
int currentPage, int beginIndex){ C&++VRnm
this.hasPrePage = hasPrePage; 7LO%#No",
this.hasNextPage = hasNextPage; C/(M"j M
this.everyPage = everyPage; z>w`ZD}XY
this.totalPage = totalPage; N)&4Hy
this.currentPage = currentPage; >DPB!XA3
this.beginIndex = beginIndex; OgF+OS
} jE#O>3+.
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/** ,;M4jc{
* @return !"+'A)Nve
* Returns the beginIndex. iS5W>1]
*/ O5H9Y}i]
publicint getBeginIndex(){ hDV20&hq
return beginIndex; :>itXD!
} RxMH!^
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/** &qS[%K )
* @param beginIndex w`l{LHrR
* The beginIndex to set. &K/FyY5
*/ S$2b>#@UJ
publicvoid setBeginIndex(int beginIndex){ K(XN-D/c
this.beginIndex = beginIndex; 8u!"#S#>a
}
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/** "bDs2E+W
* @return d~h:~
* Returns the currentPage. kh%{C]".1
*/ jYiv'6z
publicint getCurrentPage(){ >J u]2++lx
return currentPage; :_Eqf8T
} Jk0r&t7
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/** wO2_DyMm@
* @param currentPage nYbhy}y
* The currentPage to set. aTf`BG{kw
*/ pHoEa7:
publicvoid setCurrentPage(int currentPage){ 4nAa`(62
this.currentPage = currentPage; 7} jWBK
} !ZU2{
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/** ~^+0
* @return W
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* Returns the everyPage. \P1=5rP
*/ WoxwEi1~0
publicint getEveryPage(){ 0j C3fT!n
return everyPage; 0-{tFN
} #M A4
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/** m~uOXb
* @param everyPage b*ef);
* The everyPage to set. ':R,53tjl
*/ 7mm1P9Z
publicvoid setEveryPage(int everyPage){ f-nz{U
this.everyPage = everyPage; 1,5E`J
} uytE^
@(C1_
/** GElvz'S~
* @return UU8pz{/
* Returns the hasNextPage. ~n}k\s~|4
*/ vd6l7"0/
publicboolean getHasNextPage(){ vf4{$Oag
return hasNextPage; 6=N`wi
} :rP#I#,7w
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/** Ngg?@pG0y
* @param hasNextPage hVUP4 A
* The hasNextPage to set. `-3o+ID\
*/ -X+H2G
publicvoid setHasNextPage(boolean hasNextPage){ wb Iq&>p
this.hasNextPage = hasNextPage; kF>o.uSV
} $wYFEz
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/** ,ZS6jZ
* @return !a$ D4(`v
* Returns the hasPrePage. 2Hum!p:1
*/ $4MrP$4TI
publicboolean getHasPrePage(){ @Tfl>/%
return hasPrePage; B^%1Rpcn
} E\; ikX&1
+/D>|loRC
/** >3u]OSb
* @param hasPrePage rWh6RYd<T
* The hasPrePage to set. Q?AmOo-a
*/ N$[$;Fm:
publicvoid setHasPrePage(boolean hasPrePage){ lgpW@g
this.hasPrePage = hasPrePage; _bD/D!|
} ~afg)[(
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/** G^"Vo x4
* @return Returns the totalPage. KN"S?i]X
* T;L>P[hNn
*/ hm<}p&!J
publicint getTotalPage(){ hXGwP4
return totalPage; /*Qq[C
} XlI!{qj|
R}mn*h6
/** ^s.V;R
* @param totalPage #P#-xz
* The totalPage to set. b|zg<
*/ Z!0]/ mCE8
publicvoid setTotalPage(int totalPage){ "7>>I D
this.totalPage = totalPage; f&D]anf33
} 8}w6z7e|{
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} Ap{}^
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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 1009ES7*
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个PageUtil,负责对Page对象进行构造: L !4t[hhe=
java代码: Q!,<@b)
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/*Created on 2005-4-14*/ r}yG0c,
package org.flyware.util.page; %r)avI
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import org.apache.commons.logging.Log; Il.Ed-&62
import org.apache.commons.logging.LogFactory; /m _kn
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/** -G,^1AL>
* @author Joa [Pe#kzLX
* $(Ugtimdv
*/ W0jZOP5_.$
publicclass PageUtil { 7kKy\W
L}#0I+Ml7
privatestaticfinal Log logger = LogFactory.getLog 0N=X74
u9=SpgB#
(PageUtil.class); f`>/
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/** LflFe@2
* Use the origin page to create a new page <\zCpkZ'B
* @param page D}3XFuZs_
* @param totalRecords 6a}"6d/sTL
* @return $>U#
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*/ 9dh>l!2
publicstatic Page createPage(Page page, int `IINq{Zk
FI8Oz,
totalRecords){ A$g+K,.l
return createPage(page.getEveryPage(), i~J;G#b
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page.getCurrentPage(), totalRecords); B~'MBBD"
} eK /?%t
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/** HmK*b Z
* the basic page utils not including exception %=j3jj[
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handler n3MWs);5
* @param everyPage \bCX=E-
* @param currentPage 8
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* @param totalRecords Kt>X[o3m,
* @return page @&1Wyp
*/ 6pE :A@
publicstatic Page createPage(int everyPage, int ^0W(hA
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currentPage, int totalRecords){ &p<(_|Af
everyPage = getEveryPage(everyPage); :PbDU$x
currentPage = getCurrentPage(currentPage); Vv$HR
int beginIndex = getBeginIndex(everyPage, 0%s|Zbo!>
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currentPage); {+zJI-XN/
int totalPage = getTotalPage(everyPage, *5$&`&,
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totalRecords); o-7>eE}+
boolean hasNextPage = hasNextPage(currentPage, vtJV"h?e"3
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totalPage); xa( m5P
boolean hasPrePage = hasPrePage(currentPage); tNs~M4TVVH
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returnnew Page(hasPrePage, hasNextPage, `P+(&taT
everyPage, totalPage, 0JRD
currentPage, T)7TyE|"2g
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beginIndex); M
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} >zY \Llv
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privatestaticint getEveryPage(int everyPage){ wN37zPnV~
return everyPage == 0 ? 10 : everyPage; 5TBI<K
} WKA'=,`v
D 7shiv|,
privatestaticint getCurrentPage(int currentPage){ J3S&3+2G
return currentPage == 0 ? 1 : currentPage; r0m)j
} T#:F]=
vd#,DU=p!
privatestaticint getBeginIndex(int everyPage, int 2>S~I"o0
?3sT"r_d@
currentPage){ ")s!L"x
return(currentPage - 1) * everyPage; d_}a`H
} HW=xvA+
Oi:JiD=
privatestaticint getTotalPage(int everyPage, int cTZ)"^z!
b'>8ZIY
totalRecords){ ;i#LIHJ
int totalPage = 0; %IpSK 0<Sp
<2
if(totalRecords % everyPage == 0) ?BCy J
totalPage = totalRecords / everyPage; zW{ 6Eg
else ;'RFo?u K
totalPage = totalRecords / everyPage + 1 ; }F`beoMAkM
<l\N|+7R
return totalPage; [UPNd!sy
} X=qS"O 1
o6j"OZcv
privatestaticboolean hasPrePage(int currentPage){ ioIv=qGdiP
return currentPage == 1 ? false : true; DOD6Liau{Q
} =.m6FRsU
X<Za9
privatestaticboolean hasNextPage(int currentPage, b5ie <s
UPCQs",
int totalPage){ coQ[@vu
return currentPage == totalPage || totalPage == [ET6(_=b
DM7}&~
0 ? false : true; 1JTbCS
} 9+CFRYC
zjbE 7^N
sz09+4h#
} bLG ]Wa
qc!xW,I
4sY[az
9rj('F&1
&R]pw`mTH
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。 f[/.I,9U^
>M^&F6
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 vrcE]5(:s
$fArk36O#
做法如下: |uha 38~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *Jnh";~b
|paP<$
的信息,和一个结果集List: q&M:17+:Q
java代码: K_-MkY?+
=mrY/:V
9$tl00
/*Created on 2005-6-13*/ N2~$rpU3
package com.adt.bo; i^%-aBZ
< tQc_
import java.util.List; ]UUI~sFE
7u%a/ <
import org.flyware.util.page.Page; QJ<[Zx
n! .2aq
/** H/i<_L P
* @author Joa <Ry$7t,
*/ u7k|7e=xk
publicclass Result { Vq}r_#!Q
G:+16XCra
private Page page; z}5<$K_U
)bW5yG!
private List content; \.>.c g
g37q/nEv
/** ;/Q6i
* The default constructor \REc8nsLy
*/ d7~j^v)=^
public Result(){ 9y+[o
super(); _om[VKJd
} w??c1)
S[U/qO)m
/** N#Ag'i4HF
* The constructor using fields Z\!rH"8
* *( *z|2
* @param page 7Dl%UG]
* @param content Kfjryo9
*/ ="lI i$>O
public Result(Page page, List content){ gB+
G'I
this.page = page; UvD-C?u'
this.content = content; ^g]xU1] *
} =x4a~=HX
v' 0!= r
/** :VFTVmr
* @return Returns the content. uYTCd ZQh
*/ ~PYFYjHC
publicList getContent(){ F"BL#g66
return content; .}p|`3$P
} G^KC&
F!R2_89iy
/** LVmY=d>
* @return Returns the page. !Zj#.6c9
*/ 5DSuUEvWcL
public Page getPage(){ 0#=W#Jl>
return page; %]GV+!3S
} )OUU]MUH
Y`]rj-8f0B
/** c(:Oyba
* @param content q2Rf@nt
* The content to set. $`Rxn*}V4#
*/ ;@!;1KDy
public void setContent(List content){ VKf6|ae
this.content = content; #01/(:7
} #ko6L3Pi
W gZ@N
/** ".M:`BoW4
* @param page pE(sV{PD
* The page to set. lbofF==(
*/ x:C@)CAr
publicvoid setPage(Page page){ !OQuEJR
this.page = page; Loc8eToZ
} +I.v!P!^
} @SQceQfB
u7 u~
p|s2G~0<
s[Gswd
<)J55++
2. 编写业务逻辑接口,并实现它(UserManager, [k~C+FI
P,`=]Y*
UserManagerImpl) .)0gz!Z
java代码: e#m1X6$.e
`OLB';D
?Hk.|5A}
/*Created on 2005-7-15*/ @|'Z@>!/pV
package com.adt.service; wNR=?Z~
6>lW5U^yA\
import net.sf.hibernate.HibernateException; 'F<Sf:?.p
(l2<+R%1
import org.flyware.util.page.Page; U5clQiow
X_!$Pk7ma
import com.adt.bo.Result; xT/9kM&}L
]Qc: Zy3
/** X)y*#U
* @author Joa eoJFh
*/ }R\B.2#M_@
publicinterface UserManager { <@%ma2
8m \;P
public Result listUser(Page page)throws 8W{ g
gi
'^qi2
HibernateException; W >Kp\tD
!Am
=v=>
} nT)~w
s
-/1d&
l2r>|CGQ[
s?HsUD$b
r@;$V_I
java代码: '2j~WUEmg
U<|B7t4M
"hfw9Qm
/*Created on 2005-7-15*/ $*wu~
package com.adt.service.impl; Km%8Yw0+
lej^gxj/2
import java.util.List; Wl?<c
uw00
<)"iL4 kDI
import net.sf.hibernate.HibernateException; )~G8 L Z
NCp%sGBmG
import org.flyware.util.page.Page; OfW%&LAMQ
import org.flyware.util.page.PageUtil; ~LSy7$rz
,Qga|n8C
import com.adt.bo.Result; ^75pV%<%
import com.adt.dao.UserDAO; QK,=5~I J
import com.adt.exception.ObjectNotFoundException; C?bXrG\
import com.adt.service.UserManager; m2wp m_vV#
Cnk#Ioz
/** '\4c "Ho
* @author Joa (1OW6xtfG
*/ ;k-g_{M
publicclass UserManagerImpl implements UserManager { #dL5x{gV=
uTxX`vH@!
private UserDAO userDAO; I<IC-k"Y
McO@p=M
/** hLCsQYNDU
* @param userDAO The userDAO to set. O#A8t<f|M
*/ 0,+EV,
publicvoid setUserDAO(UserDAO userDAO){ "Fo
this.userDAO = userDAO; rE9Ta8j6
} 3{I=.mUUm
wrhBH;3
/* (non-Javadoc) :A,O(
* @see com.adt.service.UserManager#listUser T,A!5V>cX
5R&x{jf$
(org.flyware.util.page.Page) |)~Ex 9%ev
*/ wbn^R'
public Result listUser(Page page)throws ?]759,Q3L
hYs82P|2Ol
HibernateException, ObjectNotFoundException { ?=TL2"L
int totalRecords = userDAO.getUserCount(); +!D=SnBGs
if(totalRecords == 0) tuX =o
throw new ObjectNotFoundException `"i^'VL,
z&\Il#'\m+
("userNotExist"); uv?8V@x2
page = PageUtil.createPage(page, totalRecords); x;<oaT$X
List users = userDAO.getUserByPage(page);
<|ka{=T
returnnew Result(page, users); I3V{"Nx6
} v/QEu^C
dw@TbJ
} [P (rY
9(i0"hS^
&Xj {:s#
7uWJ6Wk
zjZ;xn
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 W*1d
X"S
ee4KMS
询,接下来编写UserDAO的代码: nNkyOaK*4
3. UserDAO 和 UserDAOImpl: : Bdi pc
java代码: @&/s~3
y 8Ei=[
`NYF?%
/*Created on 2005-7-15*/ !3O,DhH>MC
package com.adt.dao; /F\>Z]
*##QXyyg
import java.util.List; *C[4 (DmB
k^L#,:\&V
import org.flyware.util.page.Page; GLbc/qs
l"2^S6vU
import net.sf.hibernate.HibernateException; EOMuqP)
=vB]*?;9
/** 3tJ=d'U
* @author Joa b|\{ !N]
*/ P]~N-xdV
publicinterface UserDAO extends BaseDAO { m^W*[^p
OqAh4qa,$
publicList getUserByName(String name)throws m70`{-O
s{x*~M$vt
HibernateException; E#IiyZ
?uNTUU,
publicint getUserCount()throws HibernateException; 4i ~eTb
xg*\j)_}
publicList getUserByPage(Page page)throws T%;k%
bn^mL~
HibernateException; -N /8Ho
2tg/S=t}
} GqmDDL1
<-Kb@V3
bUY:XmA
^=4I|+P,6.
{ziYd;Ys1
java代码: e
_SoM!;
"u3fs2
!;xf>API
/*Created on 2005-7-15*/ A1#4nkkc9
package com.adt.dao.impl; VuJfo9 `E
e>ZbZy?
import java.util.List; [="g|/M)
W07-JHV%
import org.flyware.util.page.Page; B` t6H
8gu'dG =
import net.sf.hibernate.HibernateException; wI1M0@}PV
import net.sf.hibernate.Query; &sr:\Qn X/
iMOPD}`IX
import com.adt.dao.UserDAO; bn<I#ZH2
!9ceCnwbNN
/** IL8'{<lM
* @author Joa 0{U ]STj
*/ tWCv]*
public class UserDAOImpl extends BaseDAOHibernateImpl )zk?yY6
z<3}TD
implements UserDAO { B J:E,P`_
dd?x5|/#
/* (non-Javadoc) #Of<1
* @see com.adt.dao.UserDAO#getUserByName #2ZrdD"5kQ
x`j$9XN5
(java.lang.String) V)WIfRs
*/ b7>-aem@I
publicList getUserByName(String name)throws )Ta]6
YKs^%GO+
HibernateException { /:*R -VdF
String querySentence = "FROM user in class n##w[7B*
"W,"qFx
com.adt.po.User WHERE user.name=:name"; ?h>%Ix
Query query = getSession().createQuery wt_?B_nR
nkr,
(querySentence); 1A)wbH)
query.setParameter("name", name); kcma/d
return query.list(); >ji}j~cH
} ]`CKQ>
o
b6?Xo/lJ.
/* (non-Javadoc) )+Y\NO?O
* @see com.adt.dao.UserDAO#getUserCount() 6a 2w-}Fs
*/ g# 9*bF
publicint getUserCount()throws HibernateException { K\Y6
cj
int count = 0; fxtYo,;$
String querySentence = "SELECT count(*) FROM @'NaA SB
n'x`oI)-
user in class com.adt.po.User"; <Vr]2mw
Query query = getSession().createQuery lhIr]'?l
Gr"2G,,VI
(querySentence); wFoR,oXtL/
count = ((Integer)query.iterate().next 6U,U[MWJ
ShsP]$Yp
()).intValue(); f4aD0.K.g|
return count; F_M~!]<na
} Xx9~
=E6i1x%j
/* (non-Javadoc) (`uC"M Lk
* @see com.adt.dao.UserDAO#getUserByPage o<Rxt
*B
c-3Y SrY
(org.flyware.util.page.Page) -V<=`e
*/ 4%c7#AX[T
publicList getUserByPage(Page page)throws B9;,A;E};
Y+PvL|`O
HibernateException { _+R_ms
String querySentence = "FROM user in class ek0;8Ds9
644hQW&W
com.adt.po.User"; AIRVvW~($
Query query = getSession().createQuery :'^dy%&UB
+2k|g2
(querySentence); rTH[?mkf4
query.setFirstResult(page.getBeginIndex()) ?XTg%U
.setMaxResults(page.getEveryPage()); MR l*rK
return query.list(); /S=;DxZ,r
} Ig?.*j ]
NdED8 iRc
} 5sV/N] !
][>M<J
Q+%m+ /Zq
~1wdAq`'a
GO:1
Z?^
至此,一个完整的分页程序完成。前台的只需要调用 J?,!1V=
5)SZd)
userManager.listUser(page)即可得到一个Page对象和结果集对象 n9-q5X^e>
2YP"nj#
的综合体,而传入的参数page对象则可以由前台传入,如果用 o"+&^
WY.\<$7
webwork,甚至可以直接在配置文件中指定。 OD@@O9
{/|8g(
下面给出一个webwork调用示例: %&Q7;?
java代码: DHu jpZXQ
E*!zJ,@8
*IO;`k q,;
/*Created on 2005-6-17*/ C6=;(=?C
package com.adt.action.user; 'm p{O
XtH_+W+O
import java.util.List; +/_B/[e<>
8Q)mmkI\=
import org.apache.commons.logging.Log; da86Jj=k
import org.apache.commons.logging.LogFactory; K&a]pL6D
import org.flyware.util.page.Page; {]_{BcK+
*mhw5Z=!
import com.adt.bo.Result; Uub%s`O
import com.adt.service.UserService; .]P;fCQmM
import com.opensymphony.xwork.Action; &fNE9peQFa
S
bqM=I+
/** p~zTRnm
* @author Joa a518N*]j
*/ o!_; H}pq
publicclass ListUser implementsAction{ Q j~W-^/ -
`\u),$
privatestaticfinal Log logger = LogFactory.getLog [{!j9E?(
z1KC$~{O
(ListUser.class); u{lDof>
z?) RF[
private UserService userService; *$Wx*Jo
$X\`
7`v
private Page page; &u`rE""
#?|1~HC
privateList users; 'hHX"\|RA
2Q_{2(nQb
/* GHsdLe=t0#
* (non-Javadoc) !vo '8r?&
* ][K8\
* @see com.opensymphony.xwork.Action#execute() >p#d;wK4_
*/ MUt^mu$86
publicString execute()throwsException{ 2D_Vo ])l/
Result result = userService.listUser(page); tS/APSY
page = result.getPage(); 6%hEs6-R
users = result.getContent(); [,?A$Z*Z|
return SUCCESS; QO`Sn N}
} K}*p(1$u
mM^8YL
/** T+`GOFx
* @return Returns the page. ppo$&W
&z
*/ H=SMDj)s+
public Page getPage(){ mt6uW+t/
return page; wTuRo
J
} #Uk6Fmu]
X|lmH{kf
/** \U =>
* @return Returns the users. 28qWC~/9
*/ B46H@]d#7K
publicList getUsers(){ uXW.
(x7"f
return users; ghd[G}
} j
tkPi)QR
K.L+;
nQ
/** f%%En5e+
* @param page ump:dL5{
* The page to set. ?;7>`F6ld
*/ M
#RuI%
publicvoid setPage(Page page){ ~9jP++&
this.page = page; R#^pNJN
} $A0]v!P~i-
*wZV*)}
/** -EIMh^
* @param users hnLgsz
* The users to set. 7}7C0mV3
*/ `,]PM)iC
publicvoid setUsers(List users){ -#z'A
this.users = users; XlcDF|?{.
} Evgq}3
_I"<?sh3
/** <y/AEY1
* @param userService 0lq4
* The userService to set. 8n
p>#V
*/ lSv;wwEg
publicvoid setUserService(UserService userService){ {'bkU9+
this.userService = userService; TZ_'nB~
} *1]k&#s
} =@/^1.`
[*E.G~IS`
u\Q**m2XP
PsT v\!
DMpd(ws
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, Jy
NY *
wq`Kyhk
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 mP+yjRw
on&=%tCAL
么只需要: *wyLX9{:
java代码: [4yQbqe;
0s[3:bZ\Ia
qCT\rZU
<?xml version="1.0"?> d(tf: @
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork \5c -L_
$ =a$z"
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +W[#;)ea(
jJC((1|
1.0.dtd"> JT_B@TO\
9uoj3Rh<
<xwork> B>21A9&
`r$WInsDu
<package name="user" extends="webwork- UoT}m^ G
ITPpT
interceptors"> JNCtsfd
w:(7fu=
<!-- The default interceptor stack name -zkL)<7
``CADiM:S
--> vK~KeZ\,p=
<default-interceptor-ref 4?uG> ;V
UwT$IKR
name="myDefaultWebStack"/> Y\S^DJy
_qNLy/AY
<action name="listUser" '0rwNEg
-{mq\GvGn
class="com.adt.action.user.ListUser"> Tz~ftf
<param +>({pHZ<S
|.W;vc <
name="page.everyPage">10</param> l[{}ZKZ
<result bncFrzp#o
C^O^Jj5X%
name="success">/user/user_list.jsp</result> K<(sqH
</action> <OB~60h"
> PA,72e
</package> <7) 6*u
Lxrn#Z eM
</xwork> 2 -8:qmP(
fbkjK`_q
"b7C0NE
IV*$U7~
b;ZAz
rJj~cPwL"
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 z5w|+9U
.q }k
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。 >xgd<
zt}p-U2I
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,KaWP
EOC"a}Cq-
fdW={}~
bd}SB -D
?QVI'R:Z?
我写的一个用于分页的类,用了泛型了,hoho -2d&Aq4m)
;Nij*-U4~
java代码: I/|n
ma/ $
" V2$g
C>ZeG
Vq
package com.intokr.util; !-~(*tn
[GM<Wt0
import java.util.List; ^q2zqC
ywte\}
/** ZeV)/g,w
* 用于分页的类<br> v21?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~Wv?p4
* !~v>&bCG>9
* @version 0.01 (P8oXb+%
* @author cheng &i RX-)^u
*/ r U5'hK
public class Paginator<E> { t,nB`g?
privateint count = 0; // 总记录数 #1R
%7*$i
privateint p = 1; // 页编号 gvYs<,:
privateint num = 20; // 每页的记录数 B[50{;X
privateList<E> results = null; // 结果 uD3_'a
e vuP4-[y
/** =<xbE;,0
* 结果总数 3J<,2
*/ t68RWzqiG[
publicint getCount(){ 1YL5 ![T
return count; 3}Qh`+Yj]
} 7i/Cax
c
@R6p+
publicvoid setCount(int count){ "dTXT
this.count = count; ~yN,F pD
} {c;3$
@Iu-F4YT
/** l-EQh*!j
* 本结果所在的页码,从1开始 <^{: K`
* +6atbbe}
* @return Returns the pageNo. W^f#xrq>
*/ =oJiNM5_u
publicint getP(){ |&7,g
return p; oJ:J'$W(
} Ags`%(
<&iBR
/** 7/L7L5h<
* if(p<=0) p=1 *_wBV
M=2
* Y2n*T
KXI,
* @param p M='Kjc>e
*/ p6'8l~W+
publicvoid setP(int p){ v'tk:Hm1
if(p <= 0) (P-<9y@
p = 1; K2 2Xo<3
this.p = p; _(foJRr
} s=4.Ovd\
/jD'o>
/** $(U|JR@
* 每页记录数量 9j`-fs@:
*/ mZyTo/\0
publicint getNum(){ wQT'~'kL
return num; stPCw$@
} nCU4a1rZ
L_,U*Jyo
/** jL SZ#H
* if(num<1) num=1 0J~4
*/ ~@JC1+
publicvoid setNum(int num){ &
j43DYw4
if(num < 1) L%FL{G
num = 1; hr5)$qZW
this.num = num; 43XuQg4
} wG
O)!u 4
7_,gAE:kG
/** .E&~]<
* 获得总页数 kns]P<g
*/ |+;"^<T)l
publicint getPageNum(){ 2B7&Ll\>
return(count - 1) / num + 1; )Yml'?V"
} e+wd>iiB
zu#o<6E{
/** D3PF(Wx
* 获得本页的开始编号,为 (p-1)*num+1 il~,y8WTU{
*/ jTnu! H2o
publicint getStart(){ /7^~*
return(p - 1) * num + 1; H;2pk
} (&(f`c@I
PW}.`
/** Cp%|Q.?
* @return Returns the results. EeO{G*pq
*/ 0*)79Sz
publicList<E> getResults(){
U{EW +>
return results; 4%TC2Laii
} N!AFsWV
T (qu~}
public void setResults(List<E> results){
cO:x{~
this.results = results; {\B!Rjt[T
} %[J( ,rm
|{
kB`
public String toString(){ iwbjjQPr
StringBuilder buff = new StringBuilder V~;YV]1Y
S4w/
kml3
(); VZ8L9h<{"
buff.append("{"); ,P}c92;
buff.append("count:").append(count); L6m'u6:1{
buff.append(",p:").append(p); #XsqTK_nk
buff.append(",nump:").append(num); 9L};vkYk#
buff.append(",results:").append |NI0zd
?@_dx=su
(results); rfjQx]3pB
buff.append("}"); O%r<I*T^r
return buff.toString(); >KE(%9y~
} 7u zN/LAF
Dng^4VRd
} >qE$:V"_5
t`Sh!e
U&6f}=vC