Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 J[6`$$l0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]"Y?
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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 dtHB@\1
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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 $n |)M+d
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分页支持类: V^9c:!aI
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java代码: JHN{vB
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package com.javaeye.common.util; 7[=MgnmuC
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import java.util.List; .wj?}Fr?97
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publicclass PaginationSupport { Bp
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publicfinalstaticint PAGESIZE = 30; 0s>ozAJ
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privateint pageSize = PAGESIZE;
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privateList items; J]|Zh
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privateint totalCount; :m~R<BQ"
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privateint[] indexes = newint[0]; 4hRc,Vq
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privateint startIndex = 0; cj=6_k
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public PaginationSupport(List items, int :Fe}.* t
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totalCount){ vwA d6Tm
setPageSize(PAGESIZE); TGUlJLT
setTotalCount(totalCount); S6~&g|T,
setItems(items); CKoRq|QG_
setStartIndex(0); X@:[.eI~
} 9 b?Nlk8d
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public PaginationSupport(List items, int yHrYSEM
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totalCount, int startIndex){ [nL{n bli
setPageSize(PAGESIZE); fa~4+jx>S
setTotalCount(totalCount); U]!~C 1cmw
setItems(items); s/' ]* n
setStartIndex(startIndex); v[P
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} Pra,r9h,
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public PaginationSupport(List items, int )#|I(Gz ^
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); C"X; ,F<
setTotalCount(totalCount); Cp[{|U-?G
setItems(items); xA?(n!{P
setStartIndex(startIndex); /j}"4_.8
} >m66j2(H*Z
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publicList getItems(){ jv<C#0E^
return items; "9>.,nzt
} )21yD1"6
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publicvoid setItems(List items){ 0m`{m'B4n
this.items = items; =Fu~ 0Wc
} m+Um^:\jX
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publicint getPageSize(){ [PRQa[_
return pageSize; eaNMcC1
} R]Iv?)Y
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publicvoid setPageSize(int pageSize){ ;ty08D/
this.pageSize = pageSize; CAs8=N#H%
} 71)DLGL
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publicint getTotalCount(){ Aw7oyC!
return totalCount; hXF#KVqx
} cN]e{|
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publicvoid setTotalCount(int totalCount){ 5(+9(
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if(totalCount > 0){ @d/Wa=K
this.totalCount = totalCount; !Z0p94L
int count = totalCount / iS/faXe5
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pageSize; c)5d-3"
if(totalCount % pageSize > 0) RWfC2$z
count++; \DDRl{
indexes = newint[count]; _T8o]
for(int i = 0; i < count; i++){ dE ,NG)MH
indexes = pageSize * VZo,AP~
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} W.|r=
}else{ D(z}c,
this.totalCount = 0; 7ThGF
} &@&0n)VTd
} T^b62j'b5_
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publicint[] getIndexes(){ ZvSWIQ6
return indexes; Vm_<eyI2
} ` D9sEt_/
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; EKr#i}(x<
} FF} A_ZFY
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publicint getStartIndex(){ xllk hD4F
return startIndex; CLn}BxgD
} K0YUN^St
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publicvoid setStartIndex(int startIndex){ 4fuKpLA
if(totalCount <= 0) 7UV hyrl
this.startIndex = 0; #<4/ * < 5
elseif(startIndex >= totalCount) GM{J3O=
this.startIndex = indexes FxK2 1
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[indexes.length - 1]; >sfH[b
elseif(startIndex < 0) zfexaf!
this.startIndex = 0; @ xBw'
else{ Bkq3-rX\
this.startIndex = indexes i!tF{'*%#
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[startIndex / pageSize]; I7Uj<a=(q
} K]bw1KK
} S2!$
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publicint getNextIndex(){ Da@H^
int nextIndex = getStartIndex() + "&Y5Nh
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pageSize; 4ne95_i
if(nextIndex >= totalCount) l&2 }/A
return getStartIndex();
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else }}cS-p
return nextIndex; HHZGu8tzt
} $%%K9Y
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publicint getPreviousIndex(){ '7j!B1K-
int previousIndex = getStartIndex() - !.^%*6f
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pageSize; s .xJ},E9
if(previousIndex < 0) L<`p;?
return0; ;OTd<
else piy_9nk
return previousIndex; {,Py%.vvR
} +OTNn@!9
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} BY&+fKae
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抽象业务类 3r]m8Hp
java代码: GK>. R<[
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/** REaU=-m-
* Created on 2005-7-12 ~\C.Nm
*/ ^rP`
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package com.javaeye.common.business; g6wL\g{29
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import java.io.Serializable; e; #"t
import java.util.List; Px$4.b[{_Y
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import org.hibernate.Criteria; ZB|y
import org.hibernate.HibernateException; "F.0(<4)
import org.hibernate.Session; YR\pt8(z?
import org.hibernate.criterion.DetachedCriteria; $v#\bqY
import org.hibernate.criterion.Projections; VEtdp*ot
import Kj+=?R~}S
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org.springframework.orm.hibernate3.HibernateCallback; ar#Xe;T!
import u5LrZt]k
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org.springframework.orm.hibernate3.support.HibernateDaoS 555*IT3b
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upport; QUSyVp{$
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import com.javaeye.common.util.PaginationSupport; ujt0?DM
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public abstract class AbstractManager extends ,Zs"r}G^
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HibernateDaoSupport {
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privateboolean cacheQueries = false; Go8?8*
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privateString queryCacheRegion; MeSF,*lP
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publicvoid setCacheQueries(boolean xKZLXQ'e-
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cacheQueries){ ;YYo^9Lh}
this.cacheQueries = cacheQueries; '%}k"&t$i
} nJ]oApb/-
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publicvoid setQueryCacheRegion(String 2^*a$OJ
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queryCacheRegion){ Km=dId7]
this.queryCacheRegion = .ZzxW
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queryCacheRegion; jEkO#xI
} |v[0(
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publicvoid save(finalObject entity){ $XOs(>~"r
getHibernateTemplate().save(entity); <EHgPlQn
} Pm
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publicvoid persist(finalObject entity){ .0 [
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getHibernateTemplate().save(entity); x bsk
} 8^8fUN4<=
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publicvoid update(finalObject entity){ !pwY@}oL
getHibernateTemplate().update(entity); 2c
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} }\s\fNSQ/
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publicvoid delete(finalObject entity){ hyPVt6Gkj
getHibernateTemplate().delete(entity); v *pN~}5
} f2abee
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publicObject load(finalClass entity, V2&O]bR
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finalSerializable id){ A5A4*.C
return getHibernateTemplate().load LrL
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(entity, id); AD** 4E
} Xv~v=.HNhk
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publicObject get(finalClass entity, &m8#^]*
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finalSerializable id){ G1vg2'A
return getHibernateTemplate().get FM80F_G^z
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(entity, id); feI%QnK)U
} TH%J=1d
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publicList findAll(finalClass entity){ Bc^%1
return getHibernateTemplate().find("from wd
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" + entity.getName()); /p&V72
} Q^|ZoJS
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publicList findByNamedQuery(finalString S1!X;PP/
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namedQuery){ g ss 3e&
return getHibernateTemplate L355uaj
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().findByNamedQuery(namedQuery); ^iHwv*ss
} t,f)!D$
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publicList findByNamedQuery(finalString query, 5 }pn5iI
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finalObject parameter){ }u>F}mUa
return getHibernateTemplate ]+!{^h$
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().findByNamedQuery(query, parameter); N>+s8L.?
} *i=+["A
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publicList findByNamedQuery(finalString query, h8ikM&fl
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finalObject[] parameters){ ;`{PA
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return getHibernateTemplate %/K'VE6pb
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().findByNamedQuery(query, parameters); /|)VO?*D
} Ji#"PE/Pt
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publicList find(finalString query){ XVlZ:kz
return getHibernateTemplate().find }:b6WN;c
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(query); 0c$0<2D%
} 0B o7EV
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publicList find(finalString query, finalObject 5q.d$K |
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parameter){ FLqF!N\G
return getHibernateTemplate().find L$Uy
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(query, parameter); V[w Y;wj
} %y{f]m
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public PaginationSupport findPageByCriteria /9K,W)h_
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria RSK~<Y@]q{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); {N \ri{|
} 9(\eL9^
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public PaginationSupport findPageByCriteria WeqE9@V
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(final DetachedCriteria detachedCriteria, finalint |>Q]q
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startIndex){ [YGPcGw
return findPageByCriteria WT-BHB1
)*b
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(detachedCriteria, PaginationSupport.PAGESIZE, *Y4[YnkPE
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startIndex); L7gZ4Hu=`
} :|Ckr-k"1e
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public PaginationSupport findPageByCriteria 86bRfW'
)@IDmz>
(final DetachedCriteria detachedCriteria, finalint @y|ZXPC#
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pageSize, pd3=^Zi
finalint startIndex){ h.QsI`@f
return(PaginationSupport) 3N5un`K7
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getHibernateTemplate().execute(new HibernateCallback(){ ke+3J\;>
publicObject doInHibernate (9"w{pnlLc
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(Session session)throws HibernateException { MHuQGc"e+4
Criteria criteria = Xscm>.di
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detachedCriteria.getExecutableCriteria(session); x)wlp{rLf
int totalCount = 5-=&4R\k
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((Integer) criteria.setProjection(Projections.rowCount :RxWHh3O
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()).uniqueResult()).intValue(); B7*^rbI:X
criteria.setProjection h()Ok9]
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(null); )\k({S
List items = ;fdROI
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criteria.setFirstResult(startIndex).setMaxResults 6>fQe8Y
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(pageSize).list(); ,y>%m;jL
PaginationSupport ps = ;Sc}e/WJj
by:"aDGK.
new PaginationSupport(items, totalCount, pageSize, zZhAH('fG
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startIndex); Pl>BTo>p'
return ps; BE#s@-zR=p
} o \#C#NiT
}, true); (i 3=XfZ!C
} fcim4dfP
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public List findAllByCriteria(final -$x5[6bN
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DetachedCriteria detachedCriteria){ r?:zKj8/u
return(List) getHibernateTemplate +K@wh
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().execute(new HibernateCallback(){ C:?mOM#_
publicObject doInHibernate dR^7d _!
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(Session session)throws HibernateException { pPa3byWf
Criteria criteria = ib-)T7V`
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detachedCriteria.getExecutableCriteria(session); FC+}gJ(q
return criteria.list(); 6]Vf`i
} &f;<[_QI=
}, true); RTLA*
} >" z$p@7
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public int getCountByCriteria(final dYEsSFB m
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DetachedCriteria detachedCriteria){ k|r+/gIV
Integer count = (Integer) fFSQLtm?E
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getHibernateTemplate().execute(new HibernateCallback(){ pZ IDGy=~
publicObject doInHibernate 3YFbT
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(Session session)throws HibernateException { # },4m
Criteria criteria = kT=KxS{
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detachedCriteria.getExecutableCriteria(session); S5,y!K]C~
return <
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criteria.setProjection(Projections.rowCount k;fy8
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()).uniqueResult(); 5C G
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} ~vL`[JiK
}, true); cD6T4
return count.intValue(); S,*
} <Rno;
} /}ADV2sF
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用户在web层构造查询条件detachedCriteria,和可选的 d,"6s=4(q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 N!TC}#}l
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PaginationSupport的实例ps。 O 8\wH
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ps.getItems()得到已分页好的结果集 mj!P
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ps.getIndexes()得到分页索引的数组 9iwSE(},
ps.getTotalCount()得到总结果数 V+Tu{fFF7E
ps.getStartIndex()当前分页索引 \nKpJ9!
ps.getNextIndex()下一页索引 m,qMRcDF
ps.getPreviousIndex()上一页索引 0&W*U{0F\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 mZgYR~
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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 &3:U&}I
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一下代码重构了。 6z-&Zu7@
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我把原本我的做法也提供出来供大家讨论吧: B.T|e,g26
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首先,为了实现分页查询,我封装了一个Page类: ;LhNz ()b
java代码: Vlka+$4!
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/*Created on 2005-4-14*/ XSv)=]{
package org.flyware.util.page; 5{.g~3"
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/** W3h{5\d!
* @author Joa g3h:oQCS
* DH*=IzcJf
*/ vp_$Ft-R
publicclass Page { R3<2Z0lqy
(UGmbRf&
/** imply if the page has previous page */ c1 ~=
privateboolean hasPrePage; <:YD.zAh|
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/** imply if the page has next page */ D$vP&7pOr4
privateboolean hasNextPage; \U\k$ (
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/** the number of every page */ V1
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privateint everyPage; 1f/8XxTB
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/** the total page number */ F,NS:mE
privateint totalPage; ss4<s
5:y
flr&+=1?D
/** the number of current page */ qUuvM
privateint currentPage; 1^HUu"Kt
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/** the begin index of the records by the current wfJ["
q
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query */ WokQ
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privateint beginIndex; k@RIM(^t
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}2;{}J
/** The default constructor */ D_(K{?KU
public Page(){ 1}#RUqFrvS
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} 28jm*Cl8
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/** construct the page by everyPage \.AI;^)X@]
* @param everyPage L[LgQ7esQ
* */ -y1t;yU.L
public Page(int everyPage){ Z,ZebS@yG
this.everyPage = everyPage; #2U4}#Mi
} ]di9dLT
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/** The whole constructor */ EvJ"%:bp
public Page(boolean hasPrePage, boolean hasNextPage, Z7@~#)3
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xn`<g|"#
int everyPage, int totalPage, 1$^=M[v
int currentPage, int beginIndex){ puPYM"
this.hasPrePage = hasPrePage; ==W`qC4n?n
this.hasNextPage = hasNextPage; tG"lI/
this.everyPage = everyPage; 50Kv4a"
this.totalPage = totalPage; lDd8dT-Q.
this.currentPage = currentPage; 1r-#QuV#
this.beginIndex = beginIndex; #]_S)_Z-
} p#T^o]+
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/** YJ[Jo3M@j0
* @return c~=yD:$
* Returns the beginIndex. 0s%rd>3
*/ } F; Nh7?
publicint getBeginIndex(){ KDmzKOl
return beginIndex; K7
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} i)[8dv
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/** Dqu][~oQ
* @param beginIndex LmA I vEr
* The beginIndex to set. 1X45~
*/ MGGc
publicvoid setBeginIndex(int beginIndex){ oO8opS7F
this.beginIndex = beginIndex; .^}
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} 4CdST3
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/** ^^m3
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* @return a|s64+
* Returns the currentPage. HN j6Iw
*/ 3|FZ!8D
publicint getCurrentPage(){ z$q:Yg
return currentPage; $kM8E@x2
} Nsd7?|@HI
ji(Y?vhQt
/** 3 IK+&hk
* @param currentPage G^ 2a<?Di
* The currentPage to set. wV,l }Xb-
*/ a!!>}e>Cj*
publicvoid setCurrentPage(int currentPage){ B2uLfi$q
this.currentPage = currentPage; '+Gy)@c
} U $ bLt
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/** :d5fU:
* @return N+[ |"v
* Returns the everyPage. D]h~\
*/ V`7^v:
publicint getEveryPage(){ -1>$3-ur~
return everyPage; 8UANB]@Y}
} s7~[7
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/** ; {P"~(S%
* @param everyPage 1 =cFV'
* The everyPage to set. %N, P?
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*/ wv ~?<DF
publicvoid setEveryPage(int everyPage){ yye(^
this.everyPage = everyPage; W,[b:[~v
} B9-Nb 4
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/** Js7D>GWP!
* @return iQI$Y]Y7
* Returns the hasNextPage. q|[P[7z
*/ %](H?'H
publicboolean getHasNextPage(){
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return hasNextPage; o=,q4;R'
} 5>e3srKu
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/** H3?HQ>&O7
* @param hasNextPage =R>%}5
* The hasNextPage to set. w<uK-]t
*/ qC%[J:RwF
publicvoid setHasNextPage(boolean hasNextPage){ 6,C,LT2^(
this.hasNextPage = hasNextPage; Nd"Rt
} e0#/3$\aSV
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/** R&OqmhT!
* @return (;11xu
* Returns the hasPrePage. 9_6.%qj&
*/ \G}$+
publicboolean getHasPrePage(){ -C7IUat<
return hasPrePage; t!g9,xG<X
} Px>Gc:!>
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/** 2|1s !Q
* @param hasPrePage 0> 6;,pd"
* The hasPrePage to set. 3gn)q>Xj$
*/ gyI(O>e
publicvoid setHasPrePage(boolean hasPrePage){ B3P#p^
this.hasPrePage = hasPrePage; LE|*Je3a
} as{^~8B
B~0L'8WzW
/** 4+V+SD
* @return Returns the totalPage. %>cl0W3x
* B~/LAD_
*/ _V9 O,"DDc
publicint getTotalPage(){ tkG0xRH
return totalPage; &tULSp@J
} }Ot
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/** O>E2G]K]\
* @param totalPage $hkMJ),T~
* The totalPage to set. $=c79Al(
*/ tp3>aNj
publicvoid setTotalPage(int totalPage){ b,U3b})(
this.totalPage = totalPage; M=n_;3,o
} 9\/T #EP
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} Q/%(&4>'y
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 7H-,:8
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个PageUtil,负责对Page对象进行构造: <&?gpRK
java代码: Y}bJN%M
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/*Created on 2005-4-14*/ K8`M~P.
package org.flyware.util.page; x*~a{M,h
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import org.apache.commons.logging.Log; <(]e/}
import org.apache.commons.logging.LogFactory; *aXZONym
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/** 0,T'z,
* @author Joa |EJ&s393&
* D<rO:Er?*a
*/ VWlOMqL995
publicclass PageUtil { s<I[)FQVr
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privatestaticfinal Log logger = LogFactory.getLog TU&t 1_6
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(PageUtil.class); jhWNMu
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/** >-Qg4%m
* Use the origin page to create a new page
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* @param page ^N!l$&=
* @param totalRecords }LH>0v_<Y
* @return web=AQ5I4
*/ jb' hqz
publicstatic Page createPage(Page page, int p%A(5DE
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totalRecords){ Phsdn`,
return createPage(page.getEveryPage(), L%8>deE>;D
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page.getCurrentPage(), totalRecords); X51 7PT8O
} ^@
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/** kU8V,5
* the basic page utils not including exception 4]N`pD5
2&E1) ^
handler [?<"SJ,`
* @param everyPage /3*75
* @param currentPage x@F"ZiYD@O
* @param totalRecords G
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* @return page 8k$iz@e
*/ ,Ty>sZ#/fz
publicstatic Page createPage(int everyPage, int )*@Oz
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currentPage, int totalRecords){ \A\a=A[
everyPage = getEveryPage(everyPage); xo0",i
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currentPage = getCurrentPage(currentPage); ,.`";='o
int beginIndex = getBeginIndex(everyPage, p~h=]o'i
4-`C !q
currentPage); =|n NC
int totalPage = getTotalPage(everyPage, DT # 1*&-
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totalRecords); G?)vqmJ%
boolean hasNextPage = hasNextPage(currentPage, Eb`U^*A
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totalPage); v7O&9a;
boolean hasPrePage = hasPrePage(currentPage); $;%-<*Co
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returnnew Page(hasPrePage, hasNextPage, "Hmo`E B0
everyPage, totalPage, /xjHzva^ w
currentPage, w$H=GF?"
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beginIndex); ,UQ4`Mh^L
} }XCHoB
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privatestaticint getEveryPage(int everyPage){ Hw34wQX
return everyPage == 0 ? 10 : everyPage;
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} \xk`o5/{
guv)[:cd;
privatestaticint getCurrentPage(int currentPage){ ,MwwA@,9-
return currentPage == 0 ? 1 : currentPage; ZD1UMB0$4
} g2 uc+p
x%ZjGDF m
privatestaticint getBeginIndex(int everyPage, int "sz)~Q'W5
dL>0"UN}-
currentPage){ b0]y$*{j
return(currentPage - 1) * everyPage; H~+D2A
} !`vm7FN"u
ARW|wXhyf
privatestaticint getTotalPage(int everyPage, int -^8gZk/(W
t&u,Od
totalRecords){ OvU]|4h
int totalPage = 0; -IJt( X|
`gy]|gS#b
if(totalRecords % everyPage == 0) -p`hevRr
totalPage = totalRecords / everyPage; KcVCA
else w,]cFT
totalPage = totalRecords / everyPage + 1 ; ,,oiL
Vw=e C"
return totalPage; =^4 vz=2
} (F_Wys=6
E9{Gaa/{
privatestaticboolean hasPrePage(int currentPage){ *J@2A)ZDv0
return currentPage == 1 ? false : true; %;9f$:U
} G*e/Ft.wf8
`9eE139V='
privatestaticboolean hasNextPage(int currentPage, \1f$]oS
.l5y!?
int totalPage){ aYe,5dK>
return currentPage == totalPage || totalPage == pL>Q'{7s3
5<Cu-X
0 ? false : true; Ul OoMGg
} +L*2 6ar6
<FmrYwt
=-{+y(<"r
} V4f~#Tp
}4Lv-9s,
$k*E^~qT
!l@IG C
\uQB%yMoz
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 A[v]^pv'
lRnst-inlI
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 2t\a/QE)E
3> -/sii
做法如下: |)i-c`x
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Y1txI
gm9e-QIHK
的信息,和一个结果集List: \?h +
java代码: #B|`F?o
M[D`)7=b
#ldNWwvRGj
/*Created on 2005-6-13*/ 4(2}O-~
package com.adt.bo; @DfjeS)u^
O9oVx4=
import java.util.List; &fq-U5zH
Skl1%`
import org.flyware.util.page.Page; '@RlKMnN
/ O6n[qj|
/** z}yntY]n
* @author Joa +bI &0`
*/ ;%odN
d
publicclass Result { 3zY"9KUN
?s #DD,
private Page page; "P.7FD
VR2BdfKU,
private List content; ,\4@Ao
\TkBV?W
/** pNr3u
* The default constructor I5>HB;Q
*/ W}+Q!T=
public Result(){ O[3J Px
super(); 4vPQuk!
} a*6x^R;)
+Vt@~Z4K
/** O*rKV2\
* The constructor using fields rPkV=9ull,
* BgJ;\NV
* @param page /A[AHJ<[?
* @param content y _>HQs,:
*/ ;2@MPx
public Result(Page page, List content){ {-J/
<a@
this.page = page; Wk$[;>NU3
this.content = content; tx Lo=
} KnbT2
_;W}_p}q{
/** m*|3
* @return Returns the content. {l.) *#O
*/ 1$?O5.X:
publicList getContent(){ xKEHNgen
return content; tn+i5Eso
} A5z`_b4f
K=M5d^K<E
/** NtkEb :
* @return Returns the page. .<^dv?@
*/ l~AmHw
e
public Page getPage(){ ,*?bET
$
return page; k]`I3>/L
} 7=u\D
LR]P?
/** /@lXQM9T
* @param content GfD!Z3
* The content to set. pY!@w0.
*/ 0^*4LM|z
public void setContent(List content){ j!iimdq
this.content = content; &!2
4l=!
} ae{%*
\J
pq#Hca[
/** > YKvwbCf8
* @param page fI`6]?W
* The page to set. 25t2tj@S
*/ PbJn8o
publicvoid setPage(Page page){ ]}i_Nq W)
this.page = page; s[nXr
} BC%t[H} >R
} _OZrH(8
' ]l,
~A}"s-Kq5
.d^8w97
&sh
%]o8
2. 编写业务逻辑接口,并实现它(UserManager, 0SwWLq
#n]js7
UserManagerImpl) 'D-eFJ5
java代码: NcZ6!wWdE
(ST/>")L
}?$d~]t)
/*Created on 2005-7-15*/ y+_GL=J
package com.adt.service; tcSn`+Bu_`
h<4WY#Y
import net.sf.hibernate.HibernateException; SWY?0Pu
QB'-`GwL
import org.flyware.util.page.Page; :-xp'_\L
hdQ[=PH)
import com.adt.bo.Result; dMCV
!$
5Z]`n
/** q62TYg}
* @author Joa 79n,bb5
*/ *$Aneq0f
publicinterface UserManager { K!7o#"GM
25XD fi75
public Result listUser(Page page)throws I5wf|wB-
|t1D8){!
HibernateException; ~=aGv%vX
Q 6{2@
} eA$9)K1GO
J~V`"uo
e57}.pF^
IfF<8~~E
3:&!Q*i;
java代码: -8HIsRh
l"*qj#FD
6c^2Nl8e
/*Created on 2005-7-15*/ QY8I_VF
package com.adt.service.impl;
k]u0US9/
Q[;!z1ur
import java.util.List; T-xcd
%E3|b6k\
import net.sf.hibernate.HibernateException; <,(6*b
X<Rh-1$8F
import org.flyware.util.page.Page; 4};iL)
import org.flyware.util.page.PageUtil; 4 C/
1u:OzyJy
import com.adt.bo.Result; #
5v 2`|)
import com.adt.dao.UserDAO; >(ku*
import com.adt.exception.ObjectNotFoundException; sl}bNzT#
import com.adt.service.UserManager; Gn<s>3E
yd]W',c
/** /i"vEI
* @author Joa mhH[jO)
*/ F2:+i#lE
publicclass UserManagerImpl implements UserManager { ;E l"dqH
M}!7/8HUC
private UserDAO userDAO; Wy.2*+5FX0
Sir7TQ4B
/** .M!6${N);
* @param userDAO The userDAO to set. (~?P7RnU%
*/ @`G_6<.`
publicvoid setUserDAO(UserDAO userDAO){ Q1 mz~r
this.userDAO = userDAO; sg;Gk/]
} 0t*JP
bLUn>ch
/* (non-Javadoc) pFXDo4eH
* @see com.adt.service.UserManager#listUser \m1r(*Ar
[h""AJ~t
(org.flyware.util.page.Page) vRp =L54z
*/ V.Dqbv
public Result listUser(Page page)throws g05:A0X#
'uGn1|Pvy
HibernateException, ObjectNotFoundException { \9geDX9A
int totalRecords = userDAO.getUserCount(); [?r`8K2!,
if(totalRecords == 0) ? ;i O
throw new ObjectNotFoundException z\*ii<-@
+yiGZV/X
("userNotExist"); rBye%rQRq
page = PageUtil.createPage(page, totalRecords); 1/c7((]7(,
List users = userDAO.getUserByPage(page); mg[=~&J^
returnnew Result(page, users); PEW^Vl-6q
} @\e2Q&O
d&&^_0O
} 4ZrX=e,
&, hhH_W
5&D)W>{d
q+.DZ
@
rY4{,4V
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &s->,-,
2>l4$G0
询,接下来编写UserDAO的代码: JOS,>;;F4
3. UserDAO 和 UserDAOImpl: |GM?4'2M.
java代码: G&)A7WaC
H{
p
;|
##~Y.9
/*Created on 2005-7-15*/ n"N!76
package com.adt.dao; fWhw I+
xbnx*4o0
import java.util.List; h-+9Bv]
6QkdH7Qf=
import org.flyware.util.page.Page; v:
cO+dQ
Uh'3c"
import net.sf.hibernate.HibernateException; jw?/@(AC6
fNPHc_?Ybj
/** kngkG|du
* @author Joa }26?bd@e`
*/ \`}Rdr!p%
publicinterface UserDAO extends BaseDAO { k"Y9Kc0XoU
U']DB h
publicList getUserByName(String name)throws dnTB$8&
#56}RV1
HibernateException; Eqc&iS~
TCYjj:/
publicint getUserCount()throws HibernateException; -lV]((I&
G7yCGT)vQ
publicList getUserByPage(Page page)throws 8u
Tq0d6(
X1?7}VO
HibernateException; =kH7
DygMavA.
} Q*&>Ui[&
s%z\szd*
`% k9@k.
6*8"?S'
J@PwN^`
java代码: ~CIA6&
wvBx]$SC
CE]0OY
/*Created on 2005-7-15*/ :akEl7/&
package com.adt.dao.impl; 8,=N~(pd`
Pz7{dQqjk#
import java.util.List; %K8Ei/p\t]
DXu#07\
import org.flyware.util.page.Page; {R%v4#nk
Kmc*z (Q
import net.sf.hibernate.HibernateException; ~Mbo`:>(4v
import net.sf.hibernate.Query; z )s{>^D
W+36"?*k3
import com.adt.dao.UserDAO; Q ]]}8l2
<@6K(
/** T;K@3]FbX
* @author Joa E/2 kX 3}
*/ O32p8AxEz
public class UserDAOImpl extends BaseDAOHibernateImpl 'Vq
<;.A
Dg3Sn|!f
implements UserDAO { RAYDl=}
f1w&D ]|S+
/* (non-Javadoc) rOQ@(aUAZ
* @see com.adt.dao.UserDAO#getUserByName &6<>hqR^
ATl.Qku@
(java.lang.String) 9Jd{HI=
*/ >
2_xRn<P
publicList getUserByName(String name)throws 2k;>nlVxX
^kJ(bBY
HibernateException { ^0vK >
String querySentence = "FROM user in class z+,l"#Vv
2Z K:S+c
com.adt.po.User WHERE user.name=:name"; x>:~=#Vi
Query query = getSession().createQuery *"Yz"PK
,rj_P
(querySentence); Qz)1wf'y
query.setParameter("name", name); xj`ni G
return query.list(); TbX#K:l
} e/hA>
f'&30lF
/* (non-Javadoc) ]S;^QZ
* @see com.adt.dao.UserDAO#getUserCount() dS]TTU1
*/ J&Ig%&/
publicint getUserCount()throws HibernateException { g$bbm}6S
int count = 0; x}v]JEIf[Q
String querySentence = "SELECT count(*) FROM
gP%S{<.?
Ey<vvZ
user in class com.adt.po.User"; 9n4vuBgv
Query query = getSession().createQuery Lt`d
{s
uc;1{[5`1q
(querySentence); \GhL{Awv&a
count = ((Integer)query.iterate().next 0'8_:|5
|R[@u=7s
()).intValue(); sjl(
return count; +e
VWTRG
} _~~:@fy
wJ#fmQXKJ5
/* (non-Javadoc) WqQAt{W/<
* @see com.adt.dao.UserDAO#getUserByPage tgmG#b*
RW| LL@r
(org.flyware.util.page.Page) mHCp^g4Q
*/ (Z(O7X(/
publicList getUserByPage(Page page)throws U8TH} 9Q
U9^o"vT
HibernateException { z }?*1c
String querySentence = "FROM user in class fLkZ'~e!
N
zrHWVD
com.adt.po.User"; LpRl!\FY$
Query query = getSession().createQuery #9{N[t
NqyKR&;
(querySentence); uP|Py.+
query.setFirstResult(page.getBeginIndex()) :yg:sU
.setMaxResults(page.getEveryPage()); PP/EZ ^]b
return query.list(); PF=BXY1<UL
} qyi5j0)W
J)(KG dk
} 3"v
k$
;Q*=AW
]`@= ;w
c%|K
x
Jv_KZDOdk
至此,一个完整的分页程序完成。前台的只需要调用 'Mp8!9=&
G bW1Lq&"
userManager.listUser(page)即可得到一个Page对象和结果集对象 t~_j+k0K#
`zf,$67>1
的综合体,而传入的参数page对象则可以由前台传入,如果用 2I:x)
%C8p!)Hu
webwork,甚至可以直接在配置文件中指定。 BpL7s
ej7
|#_IAN
下面给出一个webwork调用示例: Tfasry9'8
java代码: (41BUX
bEO\oS
B$ty`/{w,B
/*Created on 2005-6-17*/ mEK0ID\
package com.adt.action.user; /~sNx
!~sgFR8W
import java.util.List; k55s-%Ayr
OYnxEdo7
import org.apache.commons.logging.Log; o>Fc.$ngZ
import org.apache.commons.logging.LogFactory; RWyDX_z#<
import org.flyware.util.page.Page; z"7I5N
BhAWIH8@C
import com.adt.bo.Result; M$Sq3m`{!
import com.adt.service.UserService; k OYF]^uJ
import com.opensymphony.xwork.Action; 8&[Lr o9
I^}q;L![\
/** FKYPkFB
* @author Joa +Cs[]~
*/ u.\FNa
publicclass ListUser implementsAction{ ;4(ULJ*
*[VO03
privatestaticfinal Log logger = LogFactory.getLog QuB`}rfLf
~rnbuIh
(ListUser.class); ub/Z'!
`.oWmBey\
private UserService userService; L@mNfLK
kmNa),`{s
private Page page; ^Om0~)"q
\xCI8 *W
privateList users; ?=u/&3Cw
JAt$WW{
/* 6YErF|
* (non-Javadoc) V_'!#
* m-xnbTcQ
* @see com.opensymphony.xwork.Action#execute() J \06j%d,
*/
ShP&ss
publicString execute()throwsException{ X283 . ?
Result result = userService.listUser(page); qS8p )pw
page = result.getPage(); t(~V:+W 9
users = result.getContent(); ot%^FvQ[c
return SUCCESS; hB?a{#JL
} W|2o^ V
Gy;>.:n
/** ?"hrCEHV{9
* @return Returns the page. qGlbO
*/ EO.Se9ux
public Page getPage(){ f`;y
"ba
return page; i}tBB~]
} st_.~m!/
\*a7o GyH>
/** Q>ZxJ!B<k
* @return Returns the users. Ym% $!#
*/ h+\+9^l6|
publicList getUsers(){ ~nP~6Q'wSH
return users; @PQ%
xcOC7
} Os90fR
kA .U2
/** lmGVSdo
* @param page hSN{jl{L`
* The page to set. 5SB!)F]
*/ R^p'gQc$
publicvoid setPage(Page page){ \X*Es.;|x
this.page = page; p&s~O,Bw$
} TmS-w
3-=f@uH!
/** &g;&=<#I
* @param users I>bO<T`
* The users to set. qsT@aSIo9
*/ /VmtQ{KTt+
publicvoid setUsers(List users){ ~|:U"w\[=
this.users = users; 7:M`k #oDP
} A,'F`au
2@Nt6r
/** 3 P=I)q
* @param userService H1t`fyri2
* The userService to set. )X2/_3
*/ jW8,}Xs
publicvoid setUserService(UserService userService){ ?lPn{oB9"
this.userService = userService; `MLOf
} ]Pp}=hcD
} f,} (=
u
/!i`K{
w=QlQ\
&E?TR
A# E
Vr^UEu.w?
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, Vsj1!}X:
/&i6vWMhP
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 =#Z+WD-E
o*t4zF&n
么只需要: V+$^4Ht
java代码: 0X<U.Sxn
d}w}VL8l
7WMF8(j5
<?xml version="1.0"?> nb~592u
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork U [R[VY7
f=EWr8mno
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +^ cjdH*
j[RY
1.0.dtd"> z 0}JiW R
D#k ~lEPub
<xwork> %TeH#%[g>\
%MM)5MsB
<package name="user" extends="webwork- `9Rj;^NJ
iAr]Ed"9|
interceptors"> Be~'@
aN;c.1TY
<!-- The default interceptor stack name -`A+Qp)
8yC/:_ML
--> hDf!l$e.
<default-interceptor-ref *}'3|e4w}
S]Qf
p,
name="myDefaultWebStack"/> 96d&vm~m1
1wg#4h43l
<action name="listUser" u- }@^Y$M
Bfu/w
class="com.adt.action.user.ListUser"> VvUP;o&/
<param zN&m-nrw
<'N~|B/yZ
name="page.everyPage">10</param> [9;[g~;E%m
<result 4J{W8jX
`uof\D<']
name="success">/user/user_list.jsp</result> ^4~?]5Y\
</action> ]^0mh["
ANRZQpnXQ
</package> 6W/uoH=;
;w<r/dK
</xwork> O9P4r*prA
0<)Ep~!
[85b+SKW
C({r1l4[D
GD1L6kVd1
^Z+p_;J$p
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 yTR5*{?j
"!R*f $
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。 717OzrF}A?
}1mkX\wWP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .^wBv
'Y
= G>Y9Sc
+,zV
[\
tRbZX{
i3vg7V.
我写的一个用于分页的类,用了泛型了,hoho yS.)l
i.0d>G><@
java代码: `Ip``I#A
20w4
'@sq
p:ubj'(U05
package com.intokr.util; 2i$_ ,[fi
re fAgS!=q
import java.util.List; juA}7
cp&1yB
/** ge ]Z5E(1
* 用于分页的类<br> tP89gN^PA|
* 可以用于传递查询的结果也可以用于传送查询的参数<br> }\QXPU{UVd
* wAo6:)
* @version 0.01
N8)]d
* @author cheng d~KTUgH'<
*/ GA"vJFQ
public class Paginator<E> {
0v|qP
privateint count = 0; // 总记录数 $+ORq3
privateint p = 1; // 页编号 uMjL>YLq{?
privateint num = 20; // 每页的记录数 g:YUuZ
privateList<E> results = null; // 结果 H<"EE15
gNC'kCx0c
/** z+c'-!e/
* 结果总数 n5Mhp:zc,
*/ EX@Cf!GjN
publicint getCount(){ |fY#2\)Yx
return count; #V.u[:mO
} XEUS)X)
qga\icQr
publicvoid setCount(int count){ rAk;8)O$
this.count = count; Rl'xEtaN
} xLP8*lvy
b_)SMAsO7
/** #n+sbx5~7
* 本结果所在的页码,从1开始 Of#"nu
* tm.&k6%
* @return Returns the pageNo. p.5 *`, )
*/ 1
J[z ![Tf
publicint getP(){ @9lGU#
return p; *,
R ~[g
} ]YY4{E(9d
r-Oz k$
/** A:\_ \B%<
* if(p<=0) p=1 e 8^%}\F
* .*?)L3n+t
* @param p ]dT]25V
*/ (`<B#D;
publicvoid setP(int p){ nv3TxG
if(p <= 0) Z
ZT2c0AK
p = 1; Ch]q:o4
this.p = p; <bJ~Ol
} ]UrlFiR
GS*_m4.Ry6
/** G+WCE*
* 每页记录数量 /U>8vV+C
*/ Ls*Vz,3!5
publicint getNum(){ m/WDJ$d
return num; z=4E#y`?U
} \}Kad\)
W$`
WkR
/** +!t *LSF
* if(num<1) num=1 I]B9+Z?xo
*/ 5a/3nsup5
publicvoid setNum(int num){ \5b<!Nl
if(num < 1) =nCV.Wf
num = 1; mo]>Um'F
this.num = num; bBQHxH}vi
} 9lX[rBZ
V /)3d
/** /x/W>J2
* 获得总页数 :~p_(rE
*/ 6wb M$|yFj
publicint getPageNum(){ nTsPX Tat
return(count - 1) / num + 1; 3]>YBbXvE
} }'\M}YM
E8o9ufj3
/** 7KtgR=-Lb
* 获得本页的开始编号,为 (p-1)*num+1 +EZr@
*/ 0qBXL;sE
publicint getStart(){ x!onan
return(p - 1) * num + 1; .>'J ^^
} *T{KpiuP
Ds\f?\Em
/** aX~'
gq>
* @return Returns the results. efh 1-3f
*/ %Jn5M(myC
publicList<E> getResults(){ d_98%U+u
return results; vf`]
} QEEX|WM
'YEiT#+/
public void setResults(List<E> results){ $'lJ_jL
this.results = results; K$M,d-
`b
} & aF'IJC
dTVM
!=
public String toString(){ jw]IpGTt
StringBuilder buff = new StringBuilder ,aa
%{
Uzk_ae
(); cr{dl\Na
buff.append("{"); hy:K) _
buff.append("count:").append(count); bre6SP@
buff.append(",p:").append(p); :Czvwp{z
buff.append(",nump:").append(num); VE/~tT;
buff.append(",results:").append j MA%`*r
_[
`"E'
(results); 98WJ"f_ #
buff.append("}"); !v 3wl0
return buff.toString(); 4 W+ nSv
} U3w*z6OG
r3.v ^
} *tT5Zt/&Sr
St1>J.k_
c{f1_qXN