Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3Z%jx#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 P4s,N|bs`
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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 ^X:g C9
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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::w c
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分页支持类: l<s6Uu"
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java代码: "z{rC}
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package com.javaeye.common.util; ,T+.xB;Q@
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import java.util.List; &W>%E!F
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publicclass PaginationSupport { IvB)d}p
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publicfinalstaticint PAGESIZE = 30; {6;S= 9E\
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privateint pageSize = PAGESIZE; mX@!O[f%9e
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privateList items; hoZM;wC
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privateint totalCount; V<t!gT#&o!
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privateint[] indexes = newint[0]; j g(cpo d
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privateint startIndex = 0; CVGQ<,KVW
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public PaginationSupport(List items, int aq.Lnbi/X
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totalCount){ 2U'Vq
setPageSize(PAGESIZE); E~c>LF_]Q
setTotalCount(totalCount);
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setItems(items); %OT?2-d
setStartIndex(0); }r;#|=HR
} WCwM+D
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public PaginationSupport(List items, int Uk0
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,V ) |A=ml
totalCount, int startIndex){ N7dI}ju
setPageSize(PAGESIZE); kaNK@a=e|/
setTotalCount(totalCount); rSNaflYAr
setItems(items); RhSoD.Da
setStartIndex(startIndex); [?VkwFD0
} 7DWHADr
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public PaginationSupport(List items, int t ;bU#THM
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totalCount, int pageSize, int startIndex){ kD_616
setPageSize(pageSize); L9,O,f
setTotalCount(totalCount); PsyXt5Dk
setItems(items); ^:^8M4:
setStartIndex(startIndex); :<R"Kk@
} ]+@I]\S4
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publicList getItems(){ C{FE*@U.
return items; {3|h^h_R
}
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publicvoid setItems(List items){ Tu}?Q.pKo
this.items = items; &K-0ld(;
} G[a&r
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publicint getPageSize(){ W=!di3IA
return pageSize; '2xfU
} ?9:~d#p
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publicvoid setPageSize(int pageSize){ 3 UG
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this.pageSize = pageSize; e c4vX
} .v_-V?7
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publicint getTotalCount(){ t4r%EP|Zt
return totalCount; U6LENY+Ja
} oaM3#QJ
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publicvoid setTotalCount(int totalCount){ ,2Q5'!o
if(totalCount > 0){ "4/J4'-
this.totalCount = totalCount; ,O1/|Y
int count = totalCount / b'
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pageSize; xA]}/*
if(totalCount % pageSize > 0) .5GGZfJ]
count++; |,WP)
indexes = newint[count]; 0E/,l``p
for(int i = 0; i < count; i++){ ^?-wov$
indexes = pageSize * 4-~S"T8<u
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} noQS bI
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}else{ 4ZrRgx2MD
this.totalCount = 0; P,={ C6*
} Hm
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} 0{!+N6MiR
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publicint[] getIndexes(){ NRDXWscb
return indexes; -~WDv[[
} o ^Ro 54i
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publicvoid setIndexes(int[] indexes){ xpB*>zb
this.indexes = indexes; Wr;9Mz&{
} V~"-\@
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publicint getStartIndex(){ tu5T^"BqO
return startIndex; 0^>b=a
}
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publicvoid setStartIndex(int startIndex){ 8Ao pI3
if(totalCount <= 0) W|AK"vf
this.startIndex = 0; GVld]ioycG
elseif(startIndex >= totalCount) agp7zw=N
this.startIndex = indexes EdC/]
} @4by<
[indexes.length - 1]; a?8boN(
elseif(startIndex < 0) 5 =Op%
this.startIndex = 0; i.0.oy>
else{ ['Y"6[1
this.startIndex = indexes kKz>]t"A
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[startIndex / pageSize]; >h{)7Hv
} }}gtz-w
} 4{CeV7
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publicint getNextIndex(){ S$NJmXhx5
int nextIndex = getStartIndex() + {YF(6wVl
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pageSize; OZ6:u^OS]
if(nextIndex >= totalCount) xt1Ug~5
return getStartIndex(); .njk^,N
else H_>9'(
return nextIndex; |}isSCt
} %abc-q
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publicint getPreviousIndex(){ Ff&kK5}q
int previousIndex = getStartIndex() - >.&E-1[+:
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pageSize; /|>?!;
if(previousIndex < 0) 6d/1PGB
return0; IH3Nkpsg
else O 4'/C]B2
return previousIndex; ky@ZEp=
} =[nuesP'
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} ErxvGB(2
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抽象业务类 AwWo,Y399h
java代码: |./{,",
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/** .,<w_=
* Created on 2005-7-12 q0 L\{
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package com.javaeye.common.business; {h0T_8L/
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import java.io.Serializable; ([dJ'OPx$
import java.util.List; G>,43S!<
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import org.hibernate.Criteria; @ )Nw>/;o
import org.hibernate.HibernateException; `wKd##v'@
import org.hibernate.Session; Af Y]i
import org.hibernate.criterion.DetachedCriteria; U3~rtc*
import org.hibernate.criterion.Projections; y
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import NK6~qWsu
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org.springframework.orm.hibernate3.HibernateCallback; ~-
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import X8y :=k,E
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org.springframework.orm.hibernate3.support.HibernateDaoS qyzH*#d=Cf
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upport; Egmp8:nZl@
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import com.javaeye.common.util.PaginationSupport; ){*9$486
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public abstract class AbstractManager extends & tjL*/
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HibernateDaoSupport { ^~^=$fz
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privateboolean cacheQueries = false; Cs2kbG_
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privateString queryCacheRegion; =
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publicvoid setCacheQueries(boolean $bl<mG%#9
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cacheQueries){ m=rMx]k
this.cacheQueries = cacheQueries; q\xsXM
} Zs2;VW4RW
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publicvoid setQueryCacheRegion(String '&/~Sh$%
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queryCacheRegion){ %LBf'iA
this.queryCacheRegion = 2TgS
)
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queryCacheRegion; 9r>iP L2H
} 9SXpZ*Sx
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publicvoid save(finalObject entity){ <[vsGUbc
getHibernateTemplate().save(entity); f`YHZ
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} 49=
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publicvoid persist(finalObject entity){ |E&|6h1
getHibernateTemplate().save(entity); v%7Gh-P
} W@RD
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publicvoid update(finalObject entity){ +V;d^&S
getHibernateTemplate().update(entity); }=A+W2D
} eOahr:Db
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publicvoid delete(finalObject entity){ Vi#[kn'
getHibernateTemplate().delete(entity); wb ^>/
} 6Ev+!!znu
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publicObject load(finalClass entity, V`@/"Dj j
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finalSerializable id){ x"A\Z-xxz
return getHibernateTemplate().load b^A7R{G7
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(entity, id); A@Cvx7X
} &FG0v<f5Pv
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publicObject get(finalClass entity, 5%+epzy
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finalSerializable id){ Z/q'^PB
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return getHibernateTemplate().get yji>vJHu
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(entity, id); ni6zo~+W]
} }(oWXwFb&W
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publicList findAll(finalClass entity){ ,YRBYK:
return getHibernateTemplate().find("from #Q BW%L
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" + entity.getName()); WR_B:%W.
} 4#W*f3d[@:
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publicList findByNamedQuery(finalString yq!peFu
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namedQuery){ Gn4XVzB`O
return getHibernateTemplate b>]UNf"-
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().findByNamedQuery(namedQuery); 4{G>T
} GC|V>| tz#
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publicList findByNamedQuery(finalString query, Ym6v 4k!@O
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finalObject parameter){ pcQgWjfS
return getHibernateTemplate ?Zb3M
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().findByNamedQuery(query, parameter); ErFt5%FN.O
} {kvxz
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publicList findByNamedQuery(finalString query, kx;7/fH
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finalObject[] parameters){ HkY#i;%N
return getHibernateTemplate i-.AD4
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().findByNamedQuery(query, parameters); VxE;tJ>1
} ,eSpt#M
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publicList find(finalString query){ 5mZwg(si
return getHibernateTemplate().find CZ>Ujw=&k
qRz /$|.
(query); ( X+2vN
} S;oRE'kk
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publicList find(finalString query, finalObject &Lbwx&!0b
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parameter){ bdEIvf7
return getHibernateTemplate().find lq a~ZF*
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(query, parameter); mQ9shdvt-
} 'T7Y5X80$j
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public PaginationSupport findPageByCriteria U }I#;*F
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(final DetachedCriteria detachedCriteria){ ]f}(iD
return findPageByCriteria X~/-,oV=A
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;f=.SJF
} 8L]Cc!~
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public PaginationSupport findPageByCriteria (Ffa{Tt!
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(final DetachedCriteria detachedCriteria, finalint mHa~c(x
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startIndex){ "<f?.l\+
return findPageByCriteria [+="I
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(detachedCriteria, PaginationSupport.PAGESIZE, 5Zmc3&vRl
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startIndex); \rE] V,,2
} 9<kMxtk$
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public PaginationSupport findPageByCriteria yo%Nz"
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(final DetachedCriteria detachedCriteria, finalint M1T .
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pageSize, 'I:_}q
finalint startIndex){ Bwu?DK
return(PaginationSupport) IkxoW:L
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getHibernateTemplate().execute(new HibernateCallback(){ DghqSL^s
publicObject doInHibernate =NSunW!
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(Session session)throws HibernateException { AYfe_Dj
Criteria criteria = s,l*=<
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detachedCriteria.getExecutableCriteria(session); T0.sL9
int totalCount = E,cQ9}/
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((Integer) criteria.setProjection(Projections.rowCount P%
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()).uniqueResult()).intValue(); Ndyo)11z
criteria.setProjection E`{DX9^
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(null); s6#e?5J
List items = Ps;4 ]=c
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criteria.setFirstResult(startIndex).setMaxResults A
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(pageSize).list(); .F[5{XV
PaginationSupport ps = d/awQXKe7
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new PaginationSupport(items, totalCount, pageSize, 4ElS_u^cP7
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startIndex); 'pO-h,{TS
return ps; [fELf(;(
} V|*3*W
}, true); [57`V&c5
} x<@i3Y{[
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public List findAllByCriteria(final 8dJ+Ei~M
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DetachedCriteria detachedCriteria){ 3JqGLR`z3
return(List) getHibernateTemplate S,f#g?V
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().execute(new HibernateCallback(){ =
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publicObject doInHibernate jl>wvY||
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(Session session)throws HibernateException { Og?GYe^_
Criteria criteria = FMzG6nrdBN
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detachedCriteria.getExecutableCriteria(session); e AaS }g
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return criteria.list(); ~-uDN)
} P{Q$(rOe
}, true); W7{^/s5r
} B|{E[]iK
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public int getCountByCriteria(final k![H;}W
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DetachedCriteria detachedCriteria){ MmFtG-
Integer count = (Integer) #&?}h)Jr'
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getHibernateTemplate().execute(new HibernateCallback(){ _'^_9u G
publicObject doInHibernate g_?Q3
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(Session session)throws HibernateException { qv4r!x
Criteria criteria = <AP.m4N) _
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detachedCriteria.getExecutableCriteria(session); KuL+~
return "|R75m,Id
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criteria.setProjection(Projections.rowCount OKk"S_`
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()).uniqueResult(); Y##lFEt
} h`( VMf'#
}, true); s0Z)BR #
return count.intValue(); 1Tev&J
} C~.T[Mlu
} kjXwVGK=P<
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用户在web层构造查询条件detachedCriteria,和可选的 >;VZB/d
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Lr=^0
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PaginationSupport的实例ps。 #B#xSmak
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ps.getItems()得到已分页好的结果集 ]v?jfy
ps.getIndexes()得到分页索引的数组 AS[j)x!
ps.getTotalCount()得到总结果数 CC3M7|eO3
ps.getStartIndex()当前分页索引 \+0l#t$
ps.getNextIndex()下一页索引 F[W0gjUc
ps.getPreviousIndex()上一页索引 z+CX$.Z
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7r.~L
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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 L]&y[/\E1
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一下代码重构了。 <=w!:
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我把原本我的做法也提供出来供大家讨论吧: 4gWlSm)
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首先,为了实现分页查询,我封装了一个Page类: "CREls,
java代码: A..`?oGj
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/*Created on 2005-4-14*/ :2')`xT
package org.flyware.util.page; zE?dQD^OD
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/** q:iu
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* @author Joa UnEgsfN
* !41"`D!1
*/ [;ZC_fD
publicclass Page { vF>]9sMv
(A=Z,ed
/** imply if the page has previous page */ $H]NC-\+>
privateboolean hasPrePage; whrDw1>(
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/** imply if the page has next page */ S_RP&+!7
privateboolean hasNextPage; |Q";a:&$
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/** the number of every page */ Np+pJc1
privateint everyPage; uY/CiTWr
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/** the total page number */ j'hWhLax
privateint totalPage; i
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OPogH=vf
/** the number of current page */ =qL^#h83y
privateint currentPage; 2~B5?(g
ugTnz$
/** the begin index of the records by the current \=xS?(v!
y=[{:
query */ h(4\k?C5
privateint beginIndex; jpoNTl'
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/** The default constructor */ +4rd
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public Page(){ m|
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} sBqOcy
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/** construct the page by everyPage /q'-.-bo
* @param everyPage (NJ.\m
* */ wwJ s_f\
public Page(int everyPage){ j#Lj<jX!xR
this.everyPage = everyPage; FP*kA_z$
} FT-=^VA\
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/** The whole constructor */ Rtl1eJ-
public Page(boolean hasPrePage, boolean hasNextPage, NmF8BmIj
d 3#e7rQ8
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int everyPage, int totalPage, o#BI_#b
int currentPage, int beginIndex){ :hR^?{9Z4>
this.hasPrePage = hasPrePage; sb?!U"v.'
this.hasNextPage = hasNextPage; P7l3ZH( g
this.everyPage = everyPage; t -fmA?\
this.totalPage = totalPage; Sl%6F!
this.currentPage = currentPage; /;E=)(w
this.beginIndex = beginIndex; :_,3")-v
} :C,}DyZy
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/** -C!m#"PDW
* @return tT]mMlKJ
* Returns the beginIndex. 5N bq9YY
*/ =ReSlt
publicint getBeginIndex(){ 3v `@**
return beginIndex; \YF07L]qs-
} ,^eOwWV
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/** A* Pz-z>z
* @param beginIndex D*sL&Rt][Y
* The beginIndex to set. nHp$5|r<
*/ XJ" xMv
publicvoid setBeginIndex(int beginIndex){ %P(2uesd
this.beginIndex = beginIndex; aMJ2bu
} Xh/BVg7$
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/** x(~V7L>"i
* @return Ap |g[J
* Returns the currentPage. \(`C*d
*/ L&uPNcZ`-
publicint getCurrentPage(){ _?$w8 S%
return currentPage; 0(&RmR
} v!3Oq.ot
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/** NdXC8
* @param currentPage :
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* The currentPage to set. Wc;N;K52
*/ roe_H>
publicvoid setCurrentPage(int currentPage){ <yvo<R^30
this.currentPage = currentPage; B[+b%a3
} fGe"1MfU
,6"[vb#*3
/** j_0l'S aj
* @return N$.ls48a4-
* Returns the everyPage. |8GLS4.]t
*/ wgq=9\+&
publicint getEveryPage(){ ;4Xx5*E
return everyPage; eiRVw5g
} ;<xPzf
l\d[S]
/** |t;Ktl
* @param everyPage =GeGlI6
* The everyPage to set. n3 Rf:j^R
*/ o? K>ji!
publicvoid setEveryPage(int everyPage){ q^<;B Y
this.everyPage = everyPage; /sPa$D
} s:z
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/** m"AyO"}I5
* @return 57;(
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* Returns the hasNextPage. qQ,(O5$|
*/ LJt5?zQKrW
publicboolean getHasNextPage(){ Qkw_9
return hasNextPage; &W&A88FfZU
} T?`Ha\go
v`:!$U*
H=
/** |O"Pb`V+
* @param hasNextPage r "\<+$ 7
* The hasNextPage to set. pF}E`U=Z
*/ U2\k7I
publicvoid setHasNextPage(boolean hasNextPage){ OGq=OW
this.hasNextPage = hasNextPage; !9j6l0
} y'JJ#7O=
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/** D (e,R9hPU
* @return [g+WL\1
* Returns the hasPrePage. L%pAEoSG
*/ >Tn[CgH]7
publicboolean getHasPrePage(){ Dr}elR>~G=
return hasPrePage; C?6q]k]r
} N;=J)b|9
8Kn}o@Yd
/** X3ZKN;
* @param hasPrePage 1Eryw~,,9i
* The hasPrePage to set. eV0eMDY5
*/ ?tT89m3_E
publicvoid setHasPrePage(boolean hasPrePage){ FE1En
this.hasPrePage = hasPrePage; v)*eLX$
} a"k,x-EL(
Ct3+ga$
/** "#Q"gC.K
* @return Returns the totalPage. u =(.}
* 4%<D\#
*/ 1d&Q
E\2}
publicint getTotalPage(){ qs9r$o.\l
return totalPage; ~BBh 4t&
} %fh-x(4v
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/** LXR>M>a`
* @param totalPage bF +d_t
* The totalPage to set. .ffr2\'*
*/ 1 Va@w
publicvoid setTotalPage(int totalPage){ li}>xDSQ4
this.totalPage = totalPage; ^vOEG;TR<-
} 5?E;YyA
ZCfd<NS?
} %r:4'$E7|
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+]Z*_?j9{
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 t
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个PageUtil,负责对Page对象进行构造: 8PG&/"K
java代码: FGpV
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/*Created on 2005-4-14*/ !VvM
package org.flyware.util.page; `0R>r7f)H
b1Ba}
import org.apache.commons.logging.Log; f>? b2a2HX
import org.apache.commons.logging.LogFactory; Jd33QL}Hj
1flB A,6L
/** 6(q8y(.`
* @author Joa Jb8%A@Z+
* Q:Y`^jP
*/ "m}N
hoD4
publicclass PageUtil { m`@~ZIa?>B
',6d0>4*
privatestaticfinal Log logger = LogFactory.getLog xQqZi b5I
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(PageUtil.class); 48mTL+*
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/** n." XiXsN
* Use the origin page to create a new page k{^iv:
* @param page df$pT?o
* @param totalRecords \T;(k?28HN
* @return R~#&xfMd.
*/ "
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publicstatic Page createPage(Page page, int 5N|hsfkx
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totalRecords){ S&'-wAEd
return createPage(page.getEveryPage(), Lcs?2c:%
cvV8;
page.getCurrentPage(), totalRecords); d ?,wEfwp
} <!?ZH"F0
t&G #%
/** 1kh()IrA
* the basic page utils not including exception =jRC4]M})
nA+gqY6 6|
handler 1]7v3m
* @param everyPage p4Xhs@.k
* @param currentPage kyD*b3MN
* @param totalRecords NcIr;
}
* @return page ,k,+UisG
*/ LlbE]_Z!U%
publicstatic Page createPage(int everyPage, int VS5D)5w#
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currentPage, int totalRecords){ #|
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everyPage = getEveryPage(everyPage); JvtbGPz
currentPage = getCurrentPage(currentPage); wUzMB]w
int beginIndex = getBeginIndex(everyPage, 0}$R4<"{Y>
H$xUOqL
currentPage); =K9-
int totalPage = getTotalPage(everyPage, S$nEflcz
|<LW(,|A
totalRecords); U{3Pk0rZ
boolean hasNextPage = hasNextPage(currentPage, ->@iw!5xu
eXtlqU$
totalPage); H$)otDOE
boolean hasPrePage = hasPrePage(currentPage); #2qv"ntW
8fQXif\z
returnnew Page(hasPrePage, hasNextPage, =o4McV}
everyPage, totalPage, hDTM\>.c;s
currentPage, i0[mU,
ezr'"1Ba}
beginIndex); >NBwtF>
} 2| ERif;)
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privatestaticint getEveryPage(int everyPage){ RG`eNRTQ%
return everyPage == 0 ? 10 : everyPage; ?#u_x4==e
} kBrU%[0O
H`jvT]
privatestaticint getCurrentPage(int currentPage){ ?L>}(
{9
return currentPage == 0 ? 1 : currentPage; >]?!9@#IH
} ~4ysg[`
lJU]sZ9~b
privatestaticint getBeginIndex(int everyPage, int hKN/&P^
ajD/)9S
currentPage){ !l1jQq_mK
return(currentPage - 1) * everyPage; - !s=`9o
} Y9nyKL
3x
E^EXV
privatestaticint getTotalPage(int everyPage, int NMhI0Ix$w
*6]_ 6xO
totalRecords){ [vcSt5R=
int totalPage = 0; uSNlI78D
@)3orH
if(totalRecords % everyPage == 0) ~@'DYZb-
H
totalPage = totalRecords / everyPage; jN sM&s,
else w#RfD
totalPage = totalRecords / everyPage + 1 ; gPy}.g{tH$
!F#^Peb
return totalPage; bN.U2 %~!
} OBZ:C!
SHe547X1
privatestaticboolean hasPrePage(int currentPage){ Q%_MO`<]$
return currentPage == 1 ? false : true; ROr| <
} O3(H_(P
R nk&:c
privatestaticboolean hasNextPage(int currentPage, M[Mx
g
WizVw&Iv
int totalPage){ v'u}%FC
return currentPage == totalPage || totalPage == XM?C7/^k
3qrjb]E%}
0 ? false : true; b@)nB
} p/Lk'h~
*uvE`4V^Jg
]0myoWpi3
} 4d
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@s~*>k#"#
v^1n.l %E
4XArpKA
u$y5?n|
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 wy#5p]!u
g42Z*+P6N
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 RRR=R]
)zvjsx*e=J
做法如下: ^%m~V LH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 t3;QF
Hp-vBoEk
的信息,和一个结果集List: hrTl:\
java代码: H@ .1cO
<|4L+?_(&
#^bn~
/*Created on 2005-6-13*/ ')~[J$qz
package com.adt.bo; ^TCfj^FP
-n`2>L1
import java.util.List; .7MLgC;
t$b{zv9C
import org.flyware.util.page.Page; OT}^dPQe
+&8'@v$
/** 1Et{lrgh
f
* @author Joa Xa/]}
B
*/ 6YYDp&nqEj
publicclass Result { aUEnQ%YU"
NC{8[*Kx5
private Page page; hZeF? G)L'
4F?O5&329i
private List content; >7nOR
>Ms_bfSK
/** @7OE:& #V
* The default constructor 3Vb/Mn!k
*/ ??=su.b
public Result(){ wlfq$h p
super(); (t2vt[A6ph
} )TyI~5>;
p$@l,4@{
/** "0Yb
2>F
* The constructor using fields MnD^jcx
* U&SgB[QHO
* @param page )VFS&|#\
* @param content u_X(c'aE;
*/ (c1Kg
public Result(Page page, List content){ I8{ohFFo
this.page = page; !eGUiE=
this.content = content; Ihg1%.^V\
} y_N h5
PW GNUNc
/** Cc!LJ
* @return Returns the content. %pr}Xs(-f
*/ g2W ZW#a)
publicList getContent(){ 7?"-NrW~
return content; F)hUT@
} 8Hh=Sp^
1c}LX.9 K
/** 2+qU9[kd|
* @return Returns the page. oq9gG)F
*/ bKP@-<:]
public Page getPage(){ X16r$~Pb
return page; #EX NS r
} yU< "tg E
]5j1p6;(`
/** uw9w{3]0f
* @param content <l"rn M%
* The content to set. fIm=^}?fwK
*/ W3-g]#\?
public void setContent(List content){ }-15^2
this.content = content; JzuP AI
} T,fDH!a
U~YjTjbd
/** yh"48@L'D
* @param page pl5Q2zq%
* The page to set. @rt}z+JF
*/ ]{PJ
publicvoid setPage(Page page){ H5?H{
this.page = page; \:`-"Ou(*
} #i}:CI>2
} OA{PKC
d}(b!q9
fGMuml?[ e
g%T` 6dvT
c-bTf$6}
2. 编写业务逻辑接口,并实现它(UserManager, R:t
DzE_p-
zs
UserManagerImpl) wBIhpiJX0
java代码: SbN.z
[Cf{2WB:7
>19j_[n@VC
/*Created on 2005-7-15*/ V( SRw
package com.adt.service; SH#!Y
]8ob`F`m,
import net.sf.hibernate.HibernateException; #i0f}&
EawtT
import org.flyware.util.page.Page; b{hdEb
X UcM~U-
import com.adt.bo.Result; W"ldQ
$>!tpJw
/** \R (Yf!>
* @author Joa v.Zr,Z=eV
*/ 8$y5) ~Q
publicinterface UserManager { T$Rj/u
t1
c$52b4=a
public Result listUser(Page page)throws *-.,QpgTX
w>uo-88
HibernateException; ZRLS3*`
'?dT<w=Y&
} u[?M{E/HU
mZ}C)&,m2
[V _\SQV0
+DA,|~k_
sRDxa5<MD
java代码: 4&+lc*
!0!r}#P
#5}v?
/*Created on 2005-7-15*/ /E<:=DD<
package com.adt.service.impl; `CF.-Vl3J#
qhqqCVrsW
import java.util.List; l
F*x\AT
D!nx %%q
import net.sf.hibernate.HibernateException; JWo).
\2NT7^H#
import org.flyware.util.page.Page; N(=\S:
import org.flyware.util.page.PageUtil; 19 <Lgr
*ci%c^}V
import com.adt.bo.Result; d td}P~
import com.adt.dao.UserDAO; fi;00>y
import com.adt.exception.ObjectNotFoundException; Tg\wBhJr|
import com.adt.service.UserManager; %:/?eZ
1@{qPmf^
/** J!@`tR-
* @author Joa :zLeS-
*/ W:* {7qJ
publicclass UserManagerImpl implements UserManager { 66%4p%#b4
\1mTKw)S
private UserDAO userDAO; r0/o{Y|l6
o%.0@W
/** YH/3N(],
* @param userDAO The userDAO to set. h1jEulcMtq
*/ Z]x)d|3;
publicvoid setUserDAO(UserDAO userDAO){
uhO-0H
this.userDAO = userDAO; 35PIfqm
} J{h?=vK
@'fWS^ ;&
/* (non-Javadoc) MZK%IC>
* @see com.adt.service.UserManager#listUser ZAa:f:[#f
KW-g $Ma
(org.flyware.util.page.Page) pCt0[R;?
*/ Z2^B.r#
public Result listUser(Page page)throws `=JGlN7
6UnWtLE
HibernateException, ObjectNotFoundException { O(CmdSk,
int totalRecords = userDAO.getUserCount(); a?P$8NLr
if(totalRecords == 0) Ze- MB0w
throw new ObjectNotFoundException B96"|v$
] R-<v&O
("userNotExist"); X;%*+xQ^
page = PageUtil.createPage(page, totalRecords); V.^Z)iNf^
List users = userDAO.getUserByPage(page); uPQrDr5
returnnew Result(page, users); h&j9'
} )R@M~d-o
*Ph@XkhU
} UcxMA%Pw7$
>nOzz0,
+!Lz]@9K
iDrQ4>
Y4)v>&H
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .BjnV%l7Id
<Pg<F[eDM
询,接下来编写UserDAO的代码: Kb,#Ot
3. UserDAO 和 UserDAOImpl: G0&'B6I>
java代码: Zq\Vq:MX
Q3|I.I e
lJ/{.uK
/*Created on 2005-7-15*/ h(MS>=
package com.adt.dao; MR-cO Pn
=VOl
*
import java.util.List; c?XqSK`',Z
0|D
l/1
import org.flyware.util.page.Page; e=Teq~K
-VP da @@w
import net.sf.hibernate.HibernateException; <Z^qBM
fw+ VR.#2H
/** X'XH-E
* @author Joa k*Vf2O3${
*/ "'\f?A9
publicinterface UserDAO extends BaseDAO { XX|wle1Kg
ruTj#tWSo
publicList getUserByName(String name)throws 8@J5tFJ&%
5_~QS
HibernateException; rtY4B~_
]/y69ou
publicint getUserCount()throws HibernateException; :MbD=sX
QB|D_?]
publicList getUserByPage(Page page)throws rN5;W
JwMFu5 @
HibernateException; [$P.ek<
qk=0ovUzg
} ?QfomTT
8bP4
>
g=u Y{Rf
9a;8^?Ld%S
&nX,)"
java代码: =as\Tp#d
t?404
)o>1=Y`[z
/*Created on 2005-7-15*/ ?7CHHk
package com.adt.dao.impl; R4P$zB_<2
DA-W =Cc
import java.util.List; O| zLD
/aHx'TG
import org.flyware.util.page.Page; h&$,mbEoI
1l`$. k
import net.sf.hibernate.HibernateException; q26%Z)'nf
import net.sf.hibernate.Query; xFy%&SKHg
08JVX'X-mr
import com.adt.dao.UserDAO; .vJt&@NO
_z(ydL*
/** UZ}>@0
* @author Joa UOtrq=y
*/ {%Ujp9i
public class UserDAOImpl extends BaseDAOHibernateImpl I'%(f@u~
LJII7<k
implements UserDAO { |`i.8
:U$U:e
/* (non-Javadoc) Vj{}cL"MR
* @see com.adt.dao.UserDAO#getUserByName 9}DF*np`G
LwL\CE_6+
(java.lang.String) 0nOp'Ky\k
*/ =gb(<`{>
publicList getUserByName(String name)throws [J6b5
6ISDY>p
HibernateException { Wy.Xx-3W
String querySentence = "FROM user in class
T24?1
J4;Fk
com.adt.po.User WHERE user.name=:name"; #m<<]L(o8W
Query query = getSession().createQuery (!9ybH;T
7gY^a MW
(querySentence); d[Lr`=L;
query.setParameter("name", name); ,)JSXo
return query.list(); 2r~&+0sBP
} =-GHs$u%f
wBK%=7
/* (non-Javadoc) uRu)iBd D
* @see com.adt.dao.UserDAO#getUserCount() M$Of.
*/ )-4xI4
publicint getUserCount()throws HibernateException { ;4 rTm@6
int count = 0; !j|93*
String querySentence = "SELECT count(*) FROM HD95>%
o)hQ]d
user in class com.adt.po.User"; 9BM 8
Query query = getSession().createQuery &QQ8ut,;
;
3WA-nn
(querySentence); &^W91C?<6
count = ((Integer)query.iterate().next \dIQhF%%2
r$Z_Kwe.|&
()).intValue(); _^)<d$R<
return count; 6W abw:
} 4z##4^9g
w
9mi2=
/* (non-Javadoc) '9#O#I&J
* @see com.adt.dao.UserDAO#getUserByPage 3_]<H<w
k)a-odNrb
(org.flyware.util.page.Page) L--(Y+vmf
*/ \%! ~pfM I
publicList getUserByPage(Page page)throws \dz@hJl:
<Y9xHn&
HibernateException { Q/,jv5
String querySentence = "FROM user in class _@47h86Q
$"/xi `
com.adt.po.User"; 4mY(* 2:HC
Query query = getSession().createQuery 1L=6Z2*fB4
G#pRBA^
(querySentence); u{o!#_o64
query.setFirstResult(page.getBeginIndex()) e:~r_,K
.setMaxResults(page.getEveryPage()); iJ rF$Xw
return query.list(); !L#>wlX)
} 1*"t-+|
DGwN*>X
} u(s/4Lu
domaD"C
-K_p?
l
<6s?M1J
BWct0=
至此,一个完整的分页程序完成。前台的只需要调用 E .kjYIH8
uWYI p\NN
userManager.listUser(page)即可得到一个Page对象和结果集对象 s2{d<0x?v
?1?zmaS
的综合体,而传入的参数page对象则可以由前台传入,如果用 0DBA 'Cv
`KgWaf-
webwork,甚至可以直接在配置文件中指定。 Y70[Nz
HCI|6{k
下面给出一个webwork调用示例: \V#2K><
java代码: |nN{XjNfP5
rR4_=S<Mi:
]S6`",+)<f
/*Created on 2005-6-17*/ ?_L)|:WL
package com.adt.action.user; 5UQz6DK
[`~E)B1Y
import java.util.List; >h0iq
R`wL%I!?f
import org.apache.commons.logging.Log; 6_m5%c~;+r
import org.apache.commons.logging.LogFactory; \tj7Jy
import org.flyware.util.page.Page; "Z&-:1tP{9
#S/]=D
import com.adt.bo.Result; hZE" 8%\q
import com.adt.service.UserService; f;C*J1y
import com.opensymphony.xwork.Action; p`)GO.pz
n4cM
/unU
/** mZ^z%+Ca|
* @author Joa \G?GX
*/ 7|IOn5
publicclass ListUser implementsAction{ E*ug.nxy
K 9ytot
privatestaticfinal Log logger = LogFactory.getLog 'E{n1[b
@?$x
(ListUser.class); <6]TazW?S
^T[8j/9o^
private UserService userService; eC^UL5>%
:Rh?#yO5
private Page page; mTcop yp
SO#NWa<0|
privateList users; i+$G=Z#3E
BitP?6KX
/* B&~#.<23:
* (non-Javadoc) R\%&Q|
* 2nW:|*:/p6
* @see com.opensymphony.xwork.Action#execute() 3[g%T2&[
*/ S <C'#vj
publicString execute()throwsException{ (j^Qa~{mG4
Result result = userService.listUser(page); 4aAuE0
page = result.getPage(); d`he
Wv^/`
users = result.getContent(); Jhclg0q
return SUCCESS; j {w'#x,
} B>&Q]J+R
uT'}_2=:
/** x=g=e
<_
* @return Returns the page. RKu'WD?sdH
*/ ]Q Y:t:-
public Page getPage(){ @l)HX'z0d
return page; mXd,{b'
} PuvC
MD
Y40`~
/** eI8rnp(Ia
* @return Returns the users. >wz&{9ni
*/ G%{J.J41F
publicList getUsers(){ |,*N>e
return users; e>zCzKK
} 'Vwsbm
tY
F?UI8
/** C&\MDOjx
* @param page d"K~+<V}
* The page to set. Zd~'%(q
*/ .+|HJ(
publicvoid setPage(Page page){ /5qeNjI+2
this.page = page; !~+"TI}_%w
} 'R&Y pR
X]^FHYjhS
/** BI\ )vr$
* @param users ]JQ7x[
* The users to set. {BkTJQ)
*/ $#3O:aW
publicvoid setUsers(List users){ {}r#s>
this.users = users; : GVyY]qBU
} J!O{.v
]ow$VF{y
/** dNH6%1(s]0
* @param userService K4\{G
* The userService to set. K(&I8vAp
*/ 7jss3^.wA
publicvoid setUserService(UserService userService){ en6Kdqe
this.userService = userService; 5*M3sN
} >?-etl
} x$:>W3?T=^
C`qo
#&fi[|%X$
b.h:~ATgN
Gjhpi5?%8
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, 'R'P^
Yp*Dd}n`
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 )qDCh
7ojU]l y
么只需要: IUB#Vdx
java代码: >3{#S:
q1rBSlzN
DRp h?V\
<?xml version="1.0"?> Mnj\t3:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 9|kc$+(+6
V*xo3hU
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Hz?C9q3BX
\<cs:C\h7
1.0.dtd"> v[k;R
ZGILV
<xwork> /INjP~C
$KSdNFtM)A
<package name="user" extends="webwork- GyirE`
MHl ffj
interceptors"> U
+c?x2\
Pu|PIdu!08
<!-- The default interceptor stack name (R'GrN>
mEL<d,XhI
--> .<#oLM^
<default-interceptor-ref &@g~o0
79m',9{u
name="myDefaultWebStack"/> ;Jh=7wx
jXa;ovPK
<action name="listUser" {..6{~L
ivgV5)".
class="com.adt.action.user.ListUser"> OTgctw1s
<param UY(pKe>
8C,}nh
name="page.everyPage">10</param> y7f,]<%e_
<result tu4-##{
E#?Bn5-uBs
name="success">/user/user_list.jsp</result> xqZZ(jZ
</action> }PC_qQF
ID{62>R
</package> !?AgAsSmc
U?@ s`.
</xwork> FfeX;pi
D8OW|wVE
71S~*"O0f
<0EVq8h
*5e"suS2
~__r-z
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 8fI]QW
nj90`O.K
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Z.^DJ9E<1
";kwh8wB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `, lnBP3D"
wBuos}/
u&M:w5EM
+'-i (]@!'
pB;U*lt
我写的一个用于分页的类,用了泛型了,hoho g-C)y
06
[Sj _=
java代码: /JqNiqvh
\GF9;N}V
5WlBec@
package com.intokr.util; q0m>NA
E;o
"^[we
import java.util.List; K/flg|uZ/V
-XJXl}M.
/** a<E\9DL
* 用于分页的类<br> GLBzlZ?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> {uCXF~v
* Eo)
#t{{
* @version 0.01 > w-fsL
* @author cheng _c z$w5`
*/ s)A=hB-V
public class Paginator<E> { -X]?ql*%`
privateint count = 0; // 总记录数 F.Sc2n@7-
privateint p = 1; // 页编号 .or1*-B K
privateint num = 20; // 每页的记录数 RJ+["[k
privateList<E> results = null; // 结果 za,JCI
-:V0pb
/** 0Tv0:c>8;(
* 结果总数 ZZ? KD\S5
*/ r|ID]}w
publicint getCount(){ }J ^+66{
return count; ZRy'lW
} >)j`Q1Qc\
mNQ~9OJ1
publicvoid setCount(int count){ nb30<h
this.count = count; 0en
Bq>vr
} _xmS$z)TO
i-YSt5iq
/** :Z R5<Y>
* 本结果所在的页码,从1开始 U
=i=E}'
* K ; eR)
* @return Returns the pageNo. Y00hc8<
*/ "y7IH
GJ\3
publicint getP(){ 4!U)a
return p; lf9mdbm
} }m -A #4.
Lz/{
q6>
/** j /)A<j$
* if(p<=0) p=1 oc>N| ww:
* )*`cJ_t
* @param p fo"%4rkL
*/ PR2;+i3
publicvoid setP(int p){ /cX%XZg
if(p <= 0) NY3/mS3w
p = 1; bH Nf>
this.p = p; 5OM*NT t
} x4N*P
=J GL~t?
/** @c-| Sl
* 每页记录数量 0F-%C>&g
*/ EEp~\^-
publicint getNum(){ ra|Ku!
return num; 3+WmM4|
} dr gCr:Gf
x:E:~h[.^
/** \LYNrL~?J
* if(num<1) num=1 (`js/7[`H[
*/ CeINODcT
publicvoid setNum(int num){ o:c:hSV
if(num < 1) vo"?a~kY7
num = 1; -%ftPfm
this.num = num; (&!x2M
} ^JY,K
7?p>v34A
/** Vv_lBYV
* 获得总页数 V$fn$=
*/ s?7"iE
publicint getPageNum(){ 3y}8|ML
return(count - 1) / num + 1; % pQi}x
} mIW/x/I
'pHxO,vo
/** /_!Ed]
* 获得本页的开始编号,为 (p-1)*num+1 *q*$%H
*/ gXvE^fE
publicint getStart(){ B'hN3.
return(p - 1) * num + 1; h'"~t#r
} (2(y9r*1
oR~s
\Gt
/** ?#lHQT
* @return Returns the results. &l~9FE*
*/ B4eV $~<
publicList<E> getResults(){ z#GrwE,r
return results; >Q2kXwN
} "V<WC"
dYZB>
OS
public void setResults(List<E> results){ 3XIL; 5
this.results = results; P*/ig0_fM
} |e91KmiqJ
2.
f8uq
public String toString(){ [8'^"
StringBuilder buff = new StringBuilder qZ%0p*P#_
4"s/T0C
(); /pL'G`
buff.append("{"); I_is3y0
buff.append("count:").append(count); IweNe`Z
buff.append(",p:").append(p); e3WEsD+
buff.append(",nump:").append(num); fF^A9{{BS
buff.append(",results:").append \u*[mrX_B:
~_|CXPiQ8
(results); $msf~M*
buff.append("}"); AWDy_11Nm
return buff.toString(); kd OIL2T
} =%d.wH?dZ/
%&!B2z}
} `S|T&|ad0
$pajE^d4V
k1fX-2H