Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #M9rt~4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;ALkeUR[
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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 F;I % 9-R
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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 8efQ-^b.
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。 @zz4,,]
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分页支持类: YIb=rR[ $
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java代码: L=Pz0
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package com.javaeye.common.util; Stw%OP@?
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import java.util.List; DH3.4EUWS
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publicclass PaginationSupport { U$-;^=;
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publicfinalstaticint PAGESIZE = 30; 9GH11B_A
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privateint pageSize = PAGESIZE; d[cqs9=\
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privateList items; :n@j"-HA
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privateint totalCount; C(RZ09,.S
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privateint[] indexes = newint[0]; gj\'1(Ju
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privateint startIndex = 0; n!nXM
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public PaginationSupport(List items, int N-lo[bDJh
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totalCount){ Z9TUaMhF
setPageSize(PAGESIZE); Y?1
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setTotalCount(totalCount); o$S/EZ
setItems(items); ZSB_OS[N
setStartIndex(0); X =sC8E dx
} s>pOfXIx
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public PaginationSupport(List items, int ;q8tOvQ
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wl
totalCount, int startIndex){ f3g#(1
setPageSize(PAGESIZE); uQ} 0hs
setTotalCount(totalCount); `oDs]90
setItems(items); %[l*:05
setStartIndex(startIndex); \R m2c8Z2
} x]1G u
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public PaginationSupport(List items, int #_A <C+[
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totalCount, int pageSize, int startIndex){ lphELPh
setPageSize(pageSize); \0{g~cU4
setTotalCount(totalCount); 2
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setItems(items); $p(,Qz(.8
setStartIndex(startIndex); FuA8vTV{
} y([""z3<w
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publicList getItems(){ M[;N6EJH
return items; Qh3V[br
} QG|KZ8uO
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publicvoid setItems(List items){ } Fw/WD
this.items = items; gK`o;` ^
} nb
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publicint getPageSize(){ ,>:
return pageSize; BW`)q/
} (|{b ZW}
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publicvoid setPageSize(int pageSize){ C4#E N}
this.pageSize = pageSize; JTK0#+?
} #[4Mw M3
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publicint getTotalCount(){ shjq4#9
return totalCount; fn!(cE|`E
} 17itC9U
@,Re<%\
publicvoid setTotalCount(int totalCount){ N@o Ng}D&:
if(totalCount > 0){ 7]i=eD8
this.totalCount = totalCount; X_j=u1*5
int count = totalCount / 3eq VY0q
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pageSize; QGWfF,q
if(totalCount % pageSize > 0) oAMB}a;
count++; \Mujx3Fmvx
indexes = newint[count]; <@Lw '
for(int i = 0; i < count; i++){ [P,/J$v^~
indexes = pageSize * %LL*V|
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i; O_f+#K)
} oX2J2O
}else{ FY^#%0~
this.totalCount = 0; Kb<^Wdy4T
} ~#doJ:^H3
} -y@5% _-
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publicint[] getIndexes(){ Ws+Zmpk%
return indexes; SS4'yaQ
} v}$s,j3NO
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publicvoid setIndexes(int[] indexes){ @iW^OVpp<8
this.indexes = indexes; 'G.^g}N1
} NXwlRMbo
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publicint getStartIndex(){ |bHId!d
return startIndex; v4:g*MD?~
} K3c(c%$<R
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) ~7N>tjB
this.startIndex = 0; ]^='aQ
elseif(startIndex >= totalCount) *kI1NchF
this.startIndex = indexes *ybwlLg
OMr &f8
[indexes.length - 1]; 80/6-_g(
elseif(startIndex < 0) q=o"]
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this.startIndex = 0; Qx_K)
else{ pB3dx#l
this.startIndex = indexes [n53eC
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[startIndex / pageSize]; JD\:bI
} v{R:F
} jh3LD6|s}
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publicint getNextIndex(){ D]I]I!2c
int nextIndex = getStartIndex() +
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pageSize; 7R$]BY=
if(nextIndex >= totalCount) O_PKS$sz{
return getStartIndex(); l
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else Hkc:B/6
return nextIndex; 9$9Pv%F:j
} nUAs:Q
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publicint getPreviousIndex(){ HMUn+kk+
int previousIndex = getStartIndex() - .js@F/Hp
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pageSize; +sTZ)
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if(previousIndex < 0) nly`\0C
return0; u6~|].j R
else u}Q@u!~e9
return previousIndex; K1P3
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} uW.)(l
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} =w~phn
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抽象业务类 DhQYjC[
java代码: OVsZUmSG
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/** ODGOWw0
* Created on 2005-7-12 \#bk$R@
*/ EZm6WvlxSI
package com.javaeye.common.business; UuV<#N)
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import java.io.Serializable; P|"U
import java.util.List; mUj=NRq
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import org.hibernate.Criteria; zh hHA9
import org.hibernate.HibernateException; YpFh_Zr[
import org.hibernate.Session; 4XkSj9D~z
import org.hibernate.criterion.DetachedCriteria; IC-k
import org.hibernate.criterion.Projections; 0NY2Kw;
import yDt3)fP#
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org.springframework.orm.hibernate3.HibernateCallback; 49o5"M(
import Kn]c4h}@b5
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org.springframework.orm.hibernate3.support.HibernateDaoS DA[s k7
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upport; p,y(Fc~]g'
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import com.javaeye.common.util.PaginationSupport; |%F[.9Dp
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public abstract class AbstractManager extends t83n` LC
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HibernateDaoSupport { u S$:J:Drx
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privateboolean cacheQueries = false; 2
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privateString queryCacheRegion; \9T;-]
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publicvoid setCacheQueries(boolean WJG& `PP
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cacheQueries){ EwSE;R -
this.cacheQueries = cacheQueries; c\.8hd=<
} mdu5aL
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publicvoid setQueryCacheRegion(String 4\%0a,\^
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queryCacheRegion){ p]d3F^*i
this.queryCacheRegion = DrD68$,QN
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queryCacheRegion; * \@u,[,
} 33O@jbs@
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publicvoid save(finalObject entity){ tUXq!r<'dT
getHibernateTemplate().save(entity); 3|/<Pk
} 'F'v/G~F
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publicvoid persist(finalObject entity){ W/PZD (
getHibernateTemplate().save(entity); sR`WV6!9
} Qh )QdW4
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publicvoid update(finalObject entity){ +tz^ &(
getHibernateTemplate().update(entity); 0&1!9-(d
} lNSB "S
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publicvoid delete(finalObject entity){ a7#J af
getHibernateTemplate().delete(entity); ?)9mHo^
} \lVX~r4
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publicObject load(finalClass entity, }.<%46_Z-
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finalSerializable id){ #D"fCVIS
return getHibernateTemplate().load _"8\k7S*
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(entity, id); b {e nD
} xF*C0B;QL
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publicObject get(finalClass entity, ?`Oh]2n)6
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finalSerializable id){ n<;TBK
return getHibernateTemplate().get sF?N vp
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(entity, id); i[b?W$]7
} pIh%5ZU
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publicList findAll(finalClass entity){ Az2HlKF"L
return getHibernateTemplate().find("from s9 '*Vm
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" + entity.getName()); %2=nS<kC
} lgC|3]
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publicList findByNamedQuery(finalString *pN,@ZV$
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namedQuery){ 'J^E|1P
return getHibernateTemplate C[$uf
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().findByNamedQuery(namedQuery); N{@kgc
} ^Bihm] Aq
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publicList findByNamedQuery(finalString query, 8S1%;@c
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finalObject parameter){ Z']D8>d
return getHibernateTemplate W! FmC$Kc
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().findByNamedQuery(query, parameter); 3Q^@!hu
} B$b'bw.
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publicList findByNamedQuery(finalString query, !*wK4UcX"
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finalObject[] parameters){ %J\1W"I?
return getHibernateTemplate kW&{0xkGR
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().findByNamedQuery(query, parameters); RaFk/mSw
} 5B{O!SNd
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publicList find(finalString query){ Z3=DM=V;v
return getHibernateTemplate().find _s./^B_w!
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(query); K,YKU?z6
} F"9f6<ge
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publicList find(finalString query, finalObject 7\aLK#
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parameter){ =:(8F*Q
return getHibernateTemplate().find 8Z>ZjNG
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(query, parameter); 5H#3PZaQ
} ~SkdP7 )
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public PaginationSupport findPageByCriteria eRllF `*
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(final DetachedCriteria detachedCriteria){ LV{a^!f`y
return findPageByCriteria }5^j08
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sbOa]
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} T"-HBwl
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public PaginationSupport findPageByCriteria 8"+Re
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(final DetachedCriteria detachedCriteria, finalint c$
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startIndex){ Y;>0)eP
return findPageByCriteria Rxld$@~-(]
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(detachedCriteria, PaginationSupport.PAGESIZE, ^I9x@t
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startIndex); :NHh`@0F
} '3eP<earRP
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public PaginationSupport findPageByCriteria u2'xM0nQ
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(final DetachedCriteria detachedCriteria, finalint zEJ|;oL
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pageSize, N4"%!.Y
finalint startIndex){ !8ub3oj)
return(PaginationSupport) =!r9;L,?
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getHibernateTemplate().execute(new HibernateCallback(){ +\9Y;Ny
publicObject doInHibernate 5B| iBS l
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(Session session)throws HibernateException { 0o[p<<c*
Criteria criteria = z7F~;IB*u
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detachedCriteria.getExecutableCriteria(session); |{]\n/M
int totalCount = AEm?g$a
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((Integer) criteria.setProjection(Projections.rowCount DGdSu6s$
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()).uniqueResult()).intValue(); zLuej'
criteria.setProjection @Y*ONnl
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(null); y1^<!I
List items = RH^8 "%\
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criteria.setFirstResult(startIndex).setMaxResults "y/GK1C
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(pageSize).list(); {$ 4fRxj
PaginationSupport ps = 25h.u>6@{
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new PaginationSupport(items, totalCount, pageSize, _QfA'32S
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startIndex); k2N[B(&4J
return ps; 5>4<_-Tm
} R1/)Yy
}, true); z^S=ji U++
} ;id0|x
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public List findAllByCriteria(final V3K
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DetachedCriteria detachedCriteria){ om$)8'A,l
return(List) getHibernateTemplate v"6q!
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().execute(new HibernateCallback(){ '~%1p_0dq
publicObject doInHibernate 2J9_(w
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(Session session)throws HibernateException { ?n>h/[/
Criteria criteria = !HM{imT
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detachedCriteria.getExecutableCriteria(session); FSd842O
return criteria.list(); 8.Wf^j$+{
} YmFJlMK
}, true); }'a}s0h
} Z ) qc-~S
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public int getCountByCriteria(final bTE%p0
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DetachedCriteria detachedCriteria){ Y<%$;fx$Sx
Integer count = (Integer) i1ur>4Ns
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getHibernateTemplate().execute(new HibernateCallback(){ ^KhA\MzY
publicObject doInHibernate wz31e!/
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(Session session)throws HibernateException { bcC;i~9
Criteria criteria = `gfh]7T
#, W7N_mt
detachedCriteria.getExecutableCriteria(session); 6<.Ma7)lA
return i[H`u,%+(
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criteria.setProjection(Projections.rowCount 8v\BW^z3
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()).uniqueResult(); B<J}YN
} ZJ'#XZpr
}, true); Eic/#j{4
return count.intValue(); i]a0
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} kJq8"Klg
} L;H(I@p(e
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用户在web层构造查询条件detachedCriteria,和可选的 ir-srVoXy
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6%~ Z^>`N
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PaginationSupport的实例ps。 M%5qx,JQY
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ps.getItems()得到已分页好的结果集 Zsc710_
ps.getIndexes()得到分页索引的数组 c#|!^gjf
ps.getTotalCount()得到总结果数 XzgJ@
ps.getStartIndex()当前分页索引 <Qu]m.z[
ps.getNextIndex()下一页索引 q+5g+9
ps.getPreviousIndex()上一页索引 ^.aFns{wv
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _so\h.lt
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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 ~cQ./G4
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一下代码重构了。 x;dyF_*;
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我把原本我的做法也提供出来供大家讨论吧: NK;%c-r0v7
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首先,为了实现分页查询,我封装了一个Page类: 1p=^I'#
java代码: AX,V*
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/*Created on 2005-4-14*/ fmrd 7*MW
package org.flyware.util.page; \/J>I1J
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/** =~6A c}$
* @author Joa {fFZ%$
* s(jixAf
*/ j\k|5="w-
publicclass Page { W5PNp%+KE
AP5[}$TT
/** imply if the page has previous page */ g|ewc'y
privateboolean hasPrePage; jI%v[]V
#N9^C@
/** imply if the page has next page */ 8'[g?
privateboolean hasNextPage; }5
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/** the number of every page */ hAX@|G.
privateint everyPage; k=!lPIx
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/** the total page number */ ^=`7]E [p
privateint totalPage; 1=:=zyEEo
l{ <+V)
/** the number of current page */ 7.mY@
privateint currentPage; CAg~K[
k8IhQ{@
/** the begin index of the records by the current 9oBK(Sf@^
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query */ E#}OIZ\S
privateint beginIndex; #0>??]&r
}#):ZPTs
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/** The default constructor */ ;]c@%LX
public Page(){ |2t
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} VZuluV
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/** construct the page by everyPage E| eEAa
* @param everyPage BV)oF2b:
* */ ZD!?mR+-
public Page(int everyPage){ q_iPWmf
p*
this.everyPage = everyPage; X)7_@,7
} kq|(t{@Rp
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/** The whole constructor */ 8LuM eGs
public Page(boolean hasPrePage, boolean hasNextPage, >}<1
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int everyPage, int totalPage, h; " 9.
int currentPage, int beginIndex){ C\2 rSyo
this.hasPrePage = hasPrePage; x6yYx_
this.hasNextPage = hasNextPage; NzS(,F
this.everyPage = everyPage; p GZiADT
this.totalPage = totalPage; ZtHTl\z
this.currentPage = currentPage; iWu
this.beginIndex = beginIndex;
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} V'b$P2 ?^
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/** U<<@(d%T
* @return ozaM!e e\z
* Returns the beginIndex. \jA#RF.W
*/ JR6r3W
publicint getBeginIndex(){ Y oDL/
return beginIndex; m&S *S_c
} aF8'^xF
xhcFZTj/(
/** _43'W{%
* @param beginIndex lV%oIf[OB
* The beginIndex to set. CcCcuxtR
*/ M'gGoH}B+q
publicvoid setBeginIndex(int beginIndex){ T'6MAxEZUq
this.beginIndex = beginIndex; zTBf.A;e7
} f4'WT
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/** a
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* @return KBC?SxJSJc
* Returns the currentPage. trx y3k;
*/ ?Vre"6U
publicint getCurrentPage(){ [D%(Y
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return currentPage; ^(F@ #zN}
} X,xCR]+5S
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/** [&(~{#}M:
* @param currentPage j+"w2
* The currentPage to set. S:(YZ%#
*/ "ov270:
publicvoid setCurrentPage(int currentPage){ iW%~>`tT
this.currentPage = currentPage; i(qZ#oN
} NHaY&\
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/** T
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* @return `!( IQ&
* Returns the everyPage. J?#Xy9dz
*/ 0SjB&J
publicint getEveryPage(){ ,ZV>"'I:
return everyPage; ?lca#@f(
} AZ.$g?3w
WAt= T3
/** -I?8\
* @param everyPage )FpizoV q0
* The everyPage to set. a%nf
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*/ dtj+ avG
publicvoid setEveryPage(int everyPage){ {8* d{0l
this.everyPage = everyPage; 3\}>nE
} gNHS:k\"
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/** nEt{ltsS0
* @return ;Zm-B]\
* Returns the hasNextPage. h6b(FTC^
*/ H)k V8wU
publicboolean getHasNextPage(){ vf5q8/a
return hasNextPage; baoyU#X9
} +)hxYLk&I
uf^HDrr<L
/** `r'$l<(4WV
* @param hasNextPage =`ZRPA!aY
* The hasNextPage to set. nIr:a|}[
*/ =Y- .=}jp;
publicvoid setHasNextPage(boolean hasNextPage){ 5OCt Q4u
this.hasNextPage = hasNextPage; $b~[>S-Q
} XL[Dmu&
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/** ZEK,Z['
* @return OO2uE ;( 3
* Returns the hasPrePage. S]&:R)#@
*/ c)3.AgT
publicboolean getHasPrePage(){ ,j6R/sg
return hasPrePage; GT7&>}FJ)
} &\=Tm~
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/** >4#:qIU
* @param hasPrePage ODEFs?%'
* The hasPrePage to set. ~&aULY?)]
*/ 7gcR/HNeF
publicvoid setHasPrePage(boolean hasPrePage){ = GyABK
this.hasPrePage = hasPrePage; &]h`kvtBC
} d6a3\f
z/]]u.UP
/** $1$0M
* @return Returns the totalPage. M1]}yTCd
* [Tl66Eyl
*/ w4fQ~rcUIc
publicint getTotalPage(){ hFo29oN
return totalPage; g>@a
} bg!(B<!X
x6)qs-
/** H:|.e)$i
* @param totalPage k`;d_eW
* The totalPage to set. 3G[|4v?[<_
*/ >8ryA$
publicvoid setTotalPage(int totalPage){ #*q]^Is"
this.totalPage = totalPage; q_6fr$-Qh
} H$ %F0'0
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} ?nPG#Z|%
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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 x`c7*q%
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个PageUtil,负责对Page对象进行构造: eR,/}g\
java代码: c4u/tt.)
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/*Created on 2005-4-14*/ >|z:CX$]
package org.flyware.util.page; tz8fZ*n
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import org.apache.commons.logging.Log; Wsgp#W+
import org.apache.commons.logging.LogFactory; qw$9i.Z
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/** Q5}XD
* @author Joa s1E 0atT
* tfe]=_U
*/ 0%Le*C'yk
publicclass PageUtil { c~4Cpy^
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privatestaticfinal Log logger = LogFactory.getLog &l0K~7)b
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(PageUtil.class); /@|iI<|
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/** /7])]vZ_
* Use the origin page to create a new page Ka6u*:/
* @param page I`(53LCqo
* @param totalRecords `Th~r&GvF
* @return (6B;
*/ 4D2U,Ds
publicstatic Page createPage(Page page, int OX 'V
Y6&v&dA;
totalRecords){ 'YB[4Q /0
return createPage(page.getEveryPage(), PJ;WNo8
5+11J[~{
page.getCurrentPage(), totalRecords); Lu{/"&)
} G^tazAEfo
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/** SzIzQR93&
* the basic page utils not including exception Q
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handler P))BS
* @param everyPage p5$}h,7
* @param currentPage QRvyaV
* @param totalRecords 6`7tTn?n
* @return page
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*/ .hu7JM+
publicstatic Page createPage(int everyPage, int 9DJ&J{2W
V]; i$
currentPage, int totalRecords){ 1Xo0(*O
everyPage = getEveryPage(everyPage); z
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currentPage = getCurrentPage(currentPage); $1"gFg
int beginIndex = getBeginIndex(everyPage, L /:^;j`c
\#(1IC`as
currentPage); NuPlrCy;
int totalPage = getTotalPage(everyPage, \?]U*)B.r
)2RRa^=&
totalRecords); C 2nmSXV
boolean hasNextPage = hasNextPage(currentPage, {j9TzR
sWo}Xq#
totalPage); QK?V^E
boolean hasPrePage = hasPrePage(currentPage); s2"`j-iQ
b6
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returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, _,!0_\+i
currentPage, e2v`
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beginIndex); #%Bt!#
} ?[d4HKs
>({qgzV`
privatestaticint getEveryPage(int everyPage){ eJTU'aX*
return everyPage == 0 ? 10 : everyPage; z`IW[N7Z
} :Bmn<2[Y;
[:{
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privatestaticint getCurrentPage(int currentPage){ 8 7(t<3V&
return currentPage == 0 ? 1 : currentPage; {7ji m
} A!Cby!,
3s/1\m%
privatestaticint getBeginIndex(int everyPage, int L4Zt4Yuw
. 2$J-<O
currentPage){ aaig1#a@1b
return(currentPage - 1) * everyPage; k7Bh[ ..!
} l<w7
\a6
o[cOL^Xd1
privatestaticint getTotalPage(int everyPage, int La )M
9tJ0O5
totalRecords){ #0r~/gW
int totalPage = 0; Rb L?(
c 9f"5~
if(totalRecords % everyPage == 0) 9 Gd6/2
totalPage = totalRecords / everyPage; f-enF)z
else 84QOW|1
totalPage = totalRecords / everyPage + 1 ; P !i_?M
;Y\LsmZ;F
return totalPage; "G
[Nb:,CR
} wHbkF#[:i
HP.=6bJWi
privatestaticboolean hasPrePage(int currentPage){ R>O_2`c
return currentPage == 1 ? false : true; H[u9C:}9b
} gZ4'
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sNDo@u7
privatestaticboolean hasNextPage(int currentPage, PP$sdmo
(M$0'BV0
int totalPage){ s{@R|5
return currentPage == totalPage || totalPage == Ob/)f)!!
y017
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0 ? false : true; 6?F88;L
} BQ0?B*yqd
~D9Cu>d9
&^"Ru?MK
} o6MFMA+vi
d}4NL:=&
t|i NSy3
OF7hp5
SvM\9
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。 qUd7O](b=?
AB'+6QU9k
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 d$3rcH1
h p|v?3(
做法如下: QEs$9a5TE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 rJ Jx8)M
Cjf[]aNJe`
的信息,和一个结果集List: 9VxM1-8Gs
java代码: p-}X=O$
8TFQ%jv
wnokP
/*Created on 2005-6-13*/ Ei_~K';
package com.adt.bo; cF8
2wg
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import java.util.List; f\hMTebma$
]?4;Lw
import org.flyware.util.page.Page; ie6c/5
%*gf_GeM
/** J=^IS\m
* @author Joa =:&xdphZ+
*/ `MVqd16Y
publicclass Result { G x[ZHpy;
aj`&ca8
private Page page; fs
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8:{id>Mm^
private List content;
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GM6,LzH
/** ELCNf
* The default constructor 3%+~"4&
*/ "Au4&Fu
public Result(){ KrpIH6
super(); *&I>3;~%^}
} Ljd`)+`D
|/gt;H~:
/** xG/Q%A
* The constructor using fields J{ju3jo
* 4f\NtQ)
* @param page W'@|ob
* @param content M-^I! C
*/ bp?5GU&Uy
public Result(Page page, List content){ ln82pQD2Y~
this.page = page; gyvrQ, u
this.content = content; ,0! 2x"Q=
} v1:.t
+yP!7]
/** uxf,95<g)
* @return Returns the content. $.jGO!
*/ X+;[Gc}(W
publicList getContent(){ ?Zb+xN KJ(
return content; dQj/Sr
} %4*c/ c6
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/** L0g+RohW
* @return Returns the page. zgAU5cw
*/ (GmBv
public Page getPage(){ d)AYY}pw
return page; h0PDFMM<
} *9j'@2!M
z)3TB&;
/** 1q7&WG
* @param content 7S{qo&j'
* The content to set. L"bJ#0m
*/ |owr?tC
public void setContent(List content){ a4,V(Hlm
this.content = content; i|^Q{3?o#
} &ys>z<Z
Q>{$Aqc,e
/** c| ?(>
* @param page ~tp]a]yV
* The page to set. uos8Mav{E
*/ nONuw;K
publicvoid setPage(Page page){ rt+4-WuK>
this.page = page; ~~/,2^
} RAO+<m
} ETHcZ
z&%i"IY
=*\.zr
xOTvrX
r{R-X3s
2. 编写业务逻辑接口,并实现它(UserManager, P~\rP6
;
Sb`[+i'`
UserManagerImpl) X"{%,]sb G
java代码: :'p)xw4K|
*J-pAN
*$eH3nn6g
/*Created on 2005-7-15*/ O)dnr8*
package com.adt.service; uuY^Q;^I*
=<n ]T;
import net.sf.hibernate.HibernateException; DsHF9Mn
D]@(LbMG4
import org.flyware.util.page.Page; b9j}QK
'##?PQ*u
import com.adt.bo.Result; A^OwT#
c]9gf\WW
/** mo| D
* @author Joa 5T;LWS
*/ ahl|N`
publicinterface UserManager { Jh\KVmfXN
&nmBsl3Q.
public Result listUser(Page page)throws c-$rB_t+
\}b2oiY
HibernateException; =z# trQ{
D:@W*,
} #`SAc`:n
f+ r>ur}\)
Usf@kVQ
{"wF;*U.V
ZG=]b%
java代码: <X8Urum
E22o-nI?1
:xsZz$
/*Created on 2005-7-15*/ `PUqz&
package com.adt.service.impl; i-CJ{l
V(&L
import java.util.List; `LkrG9KV{
Dmh$@Uu#F
import net.sf.hibernate.HibernateException; 1mmL`M1
eHgr"f*7
import org.flyware.util.page.Page; CF;Gy L1M
import org.flyware.util.page.PageUtil; {I{ 0rV
6Ryc&z5
import com.adt.bo.Result; |ty&}'6C
import com.adt.dao.UserDAO; )U\i7[k>
import com.adt.exception.ObjectNotFoundException; ]ae(t`\l^
import com.adt.service.UserManager; e1Db
+ QBV
s$#64"F
/** &[d'g0pF
* @author Joa p cLKE
ZK
*/ 0!\gK<,z
publicclass UserManagerImpl implements UserManager { \lK?f] qJq
L~&S<5?
private UserDAO userDAO; ,Q"'q0hM=
k[x-O?$O@
/** K&[0`sH!
* @param userDAO The userDAO to set. `:C1Wo^<
*/ n5QO'Jr%[
publicvoid setUserDAO(UserDAO userDAO){ x]7:MG$
this.userDAO = userDAO; Vl^x_gs#_]
} &;$uU
2U./
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/* (non-Javadoc) Y(,RJ&7
* @see com.adt.service.UserManager#listUser ,l&?%H9q
5p.rd0T]l3
(org.flyware.util.page.Page) )?72 +X
*/ oCCtjr
public Result listUser(Page page)throws R2)@Q
qJ;~ANwt
HibernateException, ObjectNotFoundException { XIIq0I
int totalRecords = userDAO.getUserCount(); ?A@y4<8R|
if(totalRecords == 0) :j]6vp6
throw new ObjectNotFoundException ,ojJ;w5D
]G[ "TX,
("userNotExist"); 5RLO}Vn]
page = PageUtil.createPage(page, totalRecords); nYtkTP!J6
List users = userDAO.getUserByPage(page); [4yHXZxza
returnnew Result(page, users); Be{@ L
} Pim
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} gV]4R"/
IgbuMEfL
8>x5|
[],[LkS
EeYL~ORdi
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 CAc]SxLh
URVW5c
询,接下来编写UserDAO的代码: >)K3
3. UserDAO 和 UserDAOImpl: !/}4_s`,
java代码: 6Jgl"Jw8
j"jssbu}
0Px Hf*
/*Created on 2005-7-15*/ JlSqTfA
package com.adt.dao; yD<#Q\,
:Ou~?q%X
import java.util.List; 6@|!m '
91z=ou
import org.flyware.util.page.Page; jZIT[HM
cs2-jbRn
import net.sf.hibernate.HibernateException;
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/** oN}\bK
* @author Joa :awa
*/ }e7/F[c.U
publicinterface UserDAO extends BaseDAO { "*zDb|v
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publicList getUserByName(String name)throws ?Z|y-4 &>
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HibernateException; u4lM>(3Y}
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publicint getUserCount()throws HibernateException; .yF-<Y
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publicList getUserByPage(Page page)throws MO~T_6
ywm"{ U?8
HibernateException; _U}|Le@ e
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} M0m%S:2
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*e ffDNE!
yMW3mx301j
-}@C9Ja[?
java代码: O4-#)#-)S~
xpa+R^D5G
dZ|bw0~_!
/*Created on 2005-7-15*/ N_D=j6B
package com.adt.dao.impl; }*XF- U
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import java.util.List; (l][_6Q
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b
import org.flyware.util.page.Page; ]oix))'n
i8<5|du&?
import net.sf.hibernate.HibernateException; oi Q3E
import net.sf.hibernate.Query; i.9}bw
9u@
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import com.adt.dao.UserDAO; .dzw5R&
T>|+cg
/** nILUo2e~
* @author Joa 6+sz4
*/ |vi=h2*
public class UserDAOImpl extends BaseDAOHibernateImpl v2|zIZ
}!g$k
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implements UserDAO { 4-O.i\1q
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/* (non-Javadoc) G}
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* @see com.adt.dao.UserDAO#getUserByName )cN=/i
1
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(java.lang.String) d>M 0:
*/ XPYf1H
publicList getUserByName(String name)throws lN.&46
e
W*H %\Y:N
HibernateException { 6jr}l
String querySentence = "FROM user in class O0^Y1l
1|*%
com.adt.po.User WHERE user.name=:name"; \U]<HEc^
Query query = getSession().createQuery 7OZ0;fK
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(querySentence); +L?;g pVE&
query.setParameter("name", name); = r=/L
return query.list(); 6mZpyt
} 2QHu8mFU
a"O9;&};&
/* (non-Javadoc) g7%vI8Y)@
* @see com.adt.dao.UserDAO#getUserCount() }8.$)&O$^
*/ L-W*h
publicint getUserCount()throws HibernateException { _58&^:/^
int count = 0; TFc/`
String querySentence = "SELECT count(*) FROM C1HNcfa7
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user in class com.adt.po.User"; R{4[.
Query query = getSession().createQuery wj$3L3
yaj1nq!*"
(querySentence); w2"]%WS %
count = ((Integer)query.iterate().next 7<Ut/1$MI
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58{}
()).intValue(); H_JT"~_2
return count; }L Brk0]
} UL8"{-`_\
"(F:'J} X
/* (non-Javadoc) qB3&F pgW
* @see com.adt.dao.UserDAO#getUserByPage ({rescQB
TAM`i3{ D
(org.flyware.util.page.Page) 0J )VEMC
*/ P`hg*"<V
publicList getUserByPage(Page page)throws $I@. <J*
x@@k_'~t%
HibernateException { e]jzFm~
String querySentence = "FROM user in class D>#Jh>4
RV5;EM)~[
com.adt.po.User"; P>6wr\9i[
Query query = getSession().createQuery >m9ge`!9
6mrfkYK
(querySentence); UJX5}36
query.setFirstResult(page.getBeginIndex()) tIX|oWC$q
.setMaxResults(page.getEveryPage()); =WOYZ7
return query.list(); 9hwn,=Vh)
} 9NC6q-2
j|% C?N
} D2Kh+~l
`H;O! ty&d
]kkH|b$[T
/Bnh%6#ab
IW|1)8d
至此,一个完整的分页程序完成。前台的只需要调用 yw?UA
0.Nik^~
userManager.listUser(page)即可得到一个Page对象和结果集对象 p)Q='
FCr> $
的综合体,而传入的参数page对象则可以由前台传入,如果用 b|h`v
g|3FJA/
webwork,甚至可以直接在配置文件中指定。 zQ eXN7$
-/qu."9(B
下面给出一个webwork调用示例: $
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java代码: ;@u+b0
j
8>^O]5Wo`X
g60rm1b
/*Created on 2005-6-17*/ 2ap0/l[
package com.adt.action.user; .7zdA IKW
h "r)z6Q/
import java.util.List; wvSaq+N
0/%VejZ'
import org.apache.commons.logging.Log; R75np^
import org.apache.commons.logging.LogFactory;
F_%&,"$
import org.flyware.util.page.Page; U@?Roenn
zTt6L6:u
import com.adt.bo.Result; z+@Jx~<i
import com.adt.service.UserService; ~|)'vK8W
import com.opensymphony.xwork.Action; T%:W6fH7
<N;HB&mr
/** B1gBvss
* @author Joa RIl+QA
*/ Y_&