Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 U;dt-3?=.h
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^dKaa
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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 q@Yt`$VTN
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 KK3xz*W0
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分页支持类: f9=X7"dzP
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java代码: uB"m!dL
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package com.javaeye.common.util; tpzdYokh>
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import java.util.List; m)2hl~o_
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publicclass PaginationSupport { [!efQap
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publicfinalstaticint PAGESIZE = 30; CKw)J}z
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privateint pageSize = PAGESIZE; w3UJw
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privateList items; /4BXF4ksi,
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privateint totalCount; qinQ5 t
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privateint[] indexes = newint[0]; O*CX@Ne
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privateint startIndex = 0; 717m.t,x
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public PaginationSupport(List items, int [zd-=.:+M[
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totalCount){ Ybg`Z
setPageSize(PAGESIZE); =+\oL!^
setTotalCount(totalCount); KTJ$#1q
setItems(items); Q*{
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setStartIndex(0); ,IB)Kk2
} I<-"J^2
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public PaginationSupport(List items, int %K,,Sl_
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totalCount, int startIndex){ jM<Ihmh|
setPageSize(PAGESIZE); 7B :aJfxM
setTotalCount(totalCount); L%Hm#eFx
setItems(items); <xNM@!'\h
setStartIndex(startIndex); Ot<!Y M
} J0plQDe
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public PaginationSupport(List items, int /YR$#&N2
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totalCount, int pageSize, int startIndex){ SkUP9
setPageSize(pageSize); +38P$Koz{r
setTotalCount(totalCount); tqC#_[~7
setItems(items); dK$dQR#
setStartIndex(startIndex);
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} d7gSkna`5c
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publicList getItems(){ bJ}+<##
return items; h /Nt92
} q0<`XDD`
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publicvoid setItems(List items){ h2<$L
this.items = items; pU/.|Sh
} 4w[ta?&6B
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publicint getPageSize(){ ~'mhC46d
return pageSize; LvdMx]*SSr
} @h3)!#\N
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publicvoid setPageSize(int pageSize){ [AwE
this.pageSize = pageSize; !d_A? q'hN
} PdnK@a
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publicint getTotalCount(){ e/Y+S;a
return totalCount; x{5*%}lX8
} i i
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publicvoid setTotalCount(int totalCount){ zb$U'D_-f
if(totalCount > 0){ gC- 0je
this.totalCount = totalCount; xn[di-LF
int count = totalCount / Xs_y!l
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pageSize; \)WjkhG<w#
if(totalCount % pageSize > 0) 0<k!F3=
count++; X9wi:
indexes = newint[count]; C3gz)!3
for(int i = 0; i < count; i++){ _=#mmZkq
indexes = pageSize * 58,mu#yq6
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} w ?aLWySYT
}else{ (H^o8J
this.totalCount = 0; LPF?\mf ^4
} &9tsk#bA.g
} @RW%EXKt
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publicint[] getIndexes(){ "Q4{6FH+mB
return indexes; [j39A`t7
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} $_kU)<e3
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publicvoid setIndexes(int[] indexes){ $la,_Sr
this.indexes = indexes; Y.J$f<[R
} ~~mQ
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publicint getStartIndex(){ uyIA]OtyN
return startIndex; , 88}5)b[
} s]UeDZ<a
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publicvoid setStartIndex(int startIndex){ K~R{q+
if(totalCount <= 0) C/G[B?:h
this.startIndex = 0; "H8N,eb2
elseif(startIndex >= totalCount) J.d<5`7
this.startIndex = indexes zT"#9"["
9"TPDU7"
[indexes.length - 1]; |.5d ^z
elseif(startIndex < 0) Dlp::U*N'
this.startIndex = 0; M*%Z5,Tc
else{ *d 4D9(
this.startIndex = indexes mDUS9>
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[startIndex / pageSize]; r>\.b{wI
} A[MEtI=Q J
} |EunDb[Y
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publicint getNextIndex(){ gO%3~f!vY#
int nextIndex = getStartIndex() + }J1#UH_E
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pageSize; ?fGY,<c
if(nextIndex >= totalCount) c9V'Z d#
return getStartIndex(); {1[8,Ho
else %Ok.XBS)
return nextIndex; vHmn)d1pl
} b.(^CYYQ
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publicint getPreviousIndex(){ =zdRoXBY[b
int previousIndex = getStartIndex() - O#g31?TO
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pageSize; 3c)xNXq m
if(previousIndex < 0) ?uQpt(
return0; lOZZ-
else I5{SC-7
return previousIndex; BZ.H6r'Q
} ?~"RCZ[;.f
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} ^)WGc/
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抽象业务类 Nsb13mlY
java代码: Jc*A\-qC.
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/** SX#ATf6#
* Created on 2005-7-12 0t8-oui
*/ [LE_lATjU
package com.javaeye.common.business; 3$_wAt4w
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import java.io.Serializable; idHBz*3~ps
import java.util.List; YRFM1?*
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import org.hibernate.Criteria; 6B=J*8
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import org.hibernate.HibernateException; sHNt>5p
import org.hibernate.Session; ~O!v?2it8q
import org.hibernate.criterion.DetachedCriteria; 0[^f9NZ>-
import org.hibernate.criterion.Projections; YC{od5a
import ] '..G-
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org.springframework.orm.hibernate3.HibernateCallback; o}BaZ|iZ2
import OvkY zI`
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org.springframework.orm.hibernate3.support.HibernateDaoS u7K0m!
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upport; \7RP6o
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import com.javaeye.common.util.PaginationSupport; ]. eGsh2
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public abstract class AbstractManager extends >Gkkr{s9
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HibernateDaoSupport { tq{
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privateboolean cacheQueries = false; MOXDR
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privateString queryCacheRegion; 9!tRM-
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publicvoid setCacheQueries(boolean >354O6
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cacheQueries){ Hc71 .rqS
this.cacheQueries = cacheQueries; krgsmDi7
} _15r!RZ:1
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publicvoid setQueryCacheRegion(String h<[ o;E
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queryCacheRegion){ 6 LC*X
this.queryCacheRegion = F[LBQI`zq
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queryCacheRegion; HA| YLj?|g
} y 2bZo'Z
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publicvoid save(finalObject entity){ D+tn<\LF
getHibernateTemplate().save(entity); 6:Ra3!V"v
} Ef69]{E
)
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publicvoid persist(finalObject entity){ (V*ggii@
getHibernateTemplate().save(entity); M^a QH/=:"
} Gt' %:9r
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publicvoid update(finalObject entity){ P'[w9'B
getHibernateTemplate().update(entity); u>}k+8~
} ^8DC
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publicvoid delete(finalObject entity){ H'GyWG|Wx
getHibernateTemplate().delete(entity); {/N4/gu
} ))<3+^S0V\
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publicObject load(finalClass entity, BDpeAF8z
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finalSerializable id){ VHJOj
return getHibernateTemplate().load F]xo *
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(entity, id); .7"
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} (h%!Kun
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publicObject get(finalClass entity, ]oj
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finalSerializable id){ *G^QS"%
return getHibernateTemplate().get -W2 !_
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(entity, id); lIz"mk
} IZ"d s=w
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publicList findAll(finalClass entity){ >O?5mfMK
return getHibernateTemplate().find("from ex1b jM7
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" + entity.getName()); w`q):yXX
} wjDLsf,
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publicList findByNamedQuery(finalString 5#~u U
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namedQuery){ ^<Q+=\h
return getHibernateTemplate 6p])2]N>p
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().findByNamedQuery(namedQuery); =otJf~
} #}3$n/
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publicList findByNamedQuery(finalString query, +Ccj@#M;
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finalObject parameter){ @Pb!:HeJE
return getHibernateTemplate U:"E:Bxz;m
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().findByNamedQuery(query, parameter); :A.dlesv6
} /Ii a >XY
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publicList findByNamedQuery(finalString query, sz9C':`W
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finalObject[] parameters){ T_i]y4dg
return getHibernateTemplate fo@2@
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().findByNamedQuery(query, parameters); e4ym6q<6!
} kO>F, M
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publicList find(finalString query){ |]y]K%
return getHibernateTemplate().find v!JQ;OX
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(query); 0rP`BK|
} ]lV\D8#
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publicList find(finalString query, finalObject 5ELKL#(
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parameter){ nO.RB#I$F
return getHibernateTemplate().find d2Pqi* K
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(query, parameter); ~H`~&?
} 3Uw}!>`%
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public PaginationSupport findPageByCriteria c0h:Vqk-
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(final DetachedCriteria detachedCriteria){ 9Kf# jZ
return findPageByCriteria {]ie|>'=C
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); u2}zRC=
} &]~Vft
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public PaginationSupport findPageByCriteria I*hCIy#;
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(final DetachedCriteria detachedCriteria, finalint ]rU$0)VN
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startIndex){ FtHR.S=u
return findPageByCriteria !(QDhnx}9c
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(detachedCriteria, PaginationSupport.PAGESIZE, w eu3c`-a
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startIndex); X} <p|P+
} >,;,
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public PaginationSupport findPageByCriteria /a@gE^TM
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(final DetachedCriteria detachedCriteria, finalint Y_S>S(0
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pageSize, 7S'3U}Y>VX
finalint startIndex){ cG{>[Lf
return(PaginationSupport) NFxs4:]
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getHibernateTemplate().execute(new HibernateCallback(){ :jo
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publicObject doInHibernate 9OI&De5?=V
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(Session session)throws HibernateException { /1OzX'5f
Criteria criteria = JzI/kH~
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detachedCriteria.getExecutableCriteria(session); c0}* $e
int totalCount = =GGt:3Kx-
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((Integer) criteria.setProjection(Projections.rowCount ?2LRMh")$
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()).uniqueResult()).intValue(); ~m@v ~=
criteria.setProjection +eT1/x0
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(null); (4ueO~jb$
List items = yhwwF
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criteria.setFirstResult(startIndex).setMaxResults VEUdw(-?s
4Og&w]
(pageSize).list(); DSb/+8KT
PaginationSupport ps = JrZ"AId2
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new PaginationSupport(items, totalCount, pageSize, rwYlg:
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startIndex); BM6 J
return ps; AiMD"7
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} E}&Z=+v}
}, true); F^knlv'
} kWkAfzf4a
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public List findAllByCriteria(final ~x}/>-d
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DetachedCriteria detachedCriteria){ mI;#Zq_j
return(List) getHibernateTemplate X0IXj%\N
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().execute(new HibernateCallback(){ KB3zQJY
publicObject doInHibernate 0H<&*U_V
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(Session session)throws HibernateException { Nhq&Sn2
Criteria criteria = gA`x-`
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detachedCriteria.getExecutableCriteria(session); dM|&Y6
return criteria.list(); 7*D*nY4+
} MJxTzQE
}, true); *cNqgw#\qL
} e~Hx+Qp.G
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public int getCountByCriteria(final =Tdh]0
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DetachedCriteria detachedCriteria){ e7fA-,DV
Integer count = (Integer) S w<V/t
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getHibernateTemplate().execute(new HibernateCallback(){ HkgmZw,
publicObject doInHibernate X^pxu6nm-
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(Session session)throws HibernateException { ~Z ,bd$
Criteria criteria = jSY&P/[xb
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detachedCriteria.getExecutableCriteria(session); aahAUhF
return H\BhAf
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criteria.setProjection(Projections.rowCount +W=
q '6gj
()).uniqueResult(); $M `%A
} iGCA>5UE
}, true); z%
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return count.intValue(); ML6V,-KU
} E="FE.%A
} =x8F!W}Bt<
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用户在web层构造查询条件detachedCriteria,和可选的 yS*s[vT
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ^\Bm5QkS
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PaginationSupport的实例ps。 BseK?`]U"
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ps.getItems()得到已分页好的结果集 QH_0U`3
ps.getIndexes()得到分页索引的数组 o_!=-AWV
ps.getTotalCount()得到总结果数 m-{t%[Y
ps.getStartIndex()当前分页索引 s`:>"1\|
ps.getNextIndex()下一页索引 j\,HquTR
ps.getPreviousIndex()上一页索引 $}{u6*u.,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zw13Tu
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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 \,U#^Vr
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一下代码重构了。 $~#N1
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我把原本我的做法也提供出来供大家讨论吧: ."N`X\
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首先,为了实现分页查询,我封装了一个Page类: .d\<}\zZ7J
java代码: GrwoV~
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/*Created on 2005-4-14*/ ^H0`UKE
package org.flyware.util.page; w"-'
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/** DXbzl
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* @author Joa eSV_.uvsb
* [1I>Bc&o*
*/ (r&e|
publicclass Page { =y5~7&9'
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/** imply if the page has previous page */ KNR_upO8
privateboolean hasPrePage; @;T>*_Yhn
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/** imply if the page has next page */ )gO=5_^u*o
privateboolean hasNextPage; >a5M:s)
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/** the number of every page */ .EOHkhn
privateint everyPage; XHKVs
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/** the total page number */ Ch`nDIne
privateint totalPage; 0YMmW xV
s_(%1/{
/** the number of current page */ uYh6q1@"~
privateint currentPage; k\:f2%!!
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/** the begin index of the records by the current |2yTt*!-r
&9Vm3X
query */ 9.bMA<X
privateint beginIndex; (h"Yw
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/** The default constructor */ {gSR49!Q
public Page(){ owYSR?aG
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} oB3,"zY
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/** construct the page by everyPage Ivw+U-Mz
* @param everyPage $gYy3y
* */ mY+.(N7m
public Page(int everyPage){ 'O#,;n
this.everyPage = everyPage; eRlJ
} (#w8/@JxF
J- %YmUc)
/** The whole constructor */ GJ >vL
public Page(boolean hasPrePage, boolean hasNextPage, .x$!Rc}
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int everyPage, int totalPage, [zO
int currentPage, int beginIndex){ HJY_l
this.hasPrePage = hasPrePage; {J:ZM"GS
this.hasNextPage = hasNextPage; 9]Q\Pr\Ub$
this.everyPage = everyPage; QOG
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fh
this.totalPage = totalPage; B3
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this.currentPage = currentPage; 7=.}484>J
this.beginIndex = beginIndex; /MS*_
} {C=d9z~:
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/** jV_Eyi3
* @return cZ(7/Pl
* Returns the beginIndex.
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*/ st;.Po[h
publicint getBeginIndex(){ Fm\
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return beginIndex; .uAOk0^z
} /2,s-^
sje}E+{[
/** E%g_O_
* @param beginIndex 'ADaz75`*r
* The beginIndex to set. E'p5
*/ 7)S;VG k
publicvoid setBeginIndex(int beginIndex){ U=<E,tM
this.beginIndex = beginIndex; MC5M><5\
} k~ZwHx(%S
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/** opz.kP[e,
* @return H6<\7W89y
* Returns the currentPage. uJ S+;H
*/ jW6~^>S
publicint getCurrentPage(){ q#v&&]N=
return currentPage; =bUVGjr%96
} !<"H73?fl
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/** f-5vE9G3y7
* @param currentPage P;>8S:8
* The currentPage to set. V Iof4?i
*/ [YT"UVI
publicvoid setCurrentPage(int currentPage){ <Bc J;X/
this.currentPage = currentPage; mw<LNnT{8
} $CaF"5}?Ke
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/** ;4nz'9+
* @return EthnI7Y
* Returns the everyPage. 4ze-N8<[
*/ imdfin?=
publicint getEveryPage(){ S#{e@ C
return everyPage; /}?"O~5M"
} /nEh,<Y)
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/** [wAI;=.
* @param everyPage "}PaMR]
* The everyPage to set. PTe8,cD>
*/ &?(r#T
publicvoid setEveryPage(int everyPage){ YPAMf&jEF
this.everyPage = everyPage; H"4^
} `.+_}.m
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/** #RK?3?wcr
* @return C=}YKsi|R|
* Returns the hasNextPage. @dAc2<4
*/ e:IUO1#
publicboolean getHasNextPage(){ =!_e(J
return hasNextPage; x72bufd
} ' jFSv|g+0
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/** \H+/D &M
* @param hasNextPage U7U-H\t7
* The hasNextPage to set. lmb5Z-xB
*/ qp>O#tj[
publicvoid setHasNextPage(boolean hasNextPage){ |yiM7U,i
this.hasNextPage = hasNextPage; t&(}`W
} xMDx<sk
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/** fU_itb(
* @return [QA@XBy6
* Returns the hasPrePage. ~;W]0d4,\
*/ MWGW[V;
publicboolean getHasPrePage(){ Q9)/INh
return hasPrePage; ,qJ/Jt$A
} NKd!i09`
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/** K2<Q9 ,vt
* @param hasPrePage aG QC
* The hasPrePage to set. >6 [{\uPK
*/ Px&*&^Gf[b
publicvoid setHasPrePage(boolean hasPrePage){ [Y.3miE
this.hasPrePage = hasPrePage; xn(lkQ6Fm
} w\KO1 Ob
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/** |cL'4I>b9
* @return Returns the totalPage. tF SO "
* %..{ c#V
*/ } pE<P;\]k
publicint getTotalPage(){ #/t^?$8\\
return totalPage; Pq`]^^=be'
} ^R\0<\'
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/** h9c54Ux
* @param totalPage o~H4<ayy
* The totalPage to set. 8D[P*?O
*/ &;5QB
publicvoid setTotalPage(int totalPage){ A-r-^S0\
this.totalPage = totalPage; hZ-No
} UOH2I+@V
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} x2+%.$'
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:9q=o|T6D
# 4_'%~-e
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 zbZ0BD7e
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个PageUtil,负责对Page对象进行构造: _7?o/Q?F%
java代码: *[@lp7
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7
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/*Created on 2005-4-14*/ c?5e| dZz
package org.flyware.util.page; xJrRJwL
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import org.apache.commons.logging.Log; IZBU<1M
import org.apache.commons.logging.LogFactory; p't>'?UH|
#DpDmMP9R3
/** Qy`{y?T2
* @author Joa Am&/K\O
* Zp]{e6J
*/
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publicclass PageUtil { =xScHy{$
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privatestaticfinal Log logger = LogFactory.getLog vs;T}'O
|H 0+.f;
(PageUtil.class); Bh?K_{e
i6M_Gk}
/** Au,xIe!t
* Use the origin page to create a new page 4Mi~eL%D
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* @param page tKgPKWP
* @param totalRecords =z^v)=uhp
* @return G\&4_MS
*/ hX(:xc
publicstatic Page createPage(Page page, int ),y{.n:wm
SDpaW6(_
totalRecords){ _]H$rf,Rc
return createPage(page.getEveryPage(), IM),cOp=
)?RR1P-ID
page.getCurrentPage(), totalRecords); o,(MB[|hQ
} ;o }pRC
@SeE,<
/** j4Ppn
* the basic page utils not including exception We%-?l:"
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handler F-g(Hk|v
* @param everyPage 833KU_ N
* @param currentPage 0G?0 Bo
* @param totalRecords /H&:
* @return page )MqF~[k<-
*/ U,S&"`a
publicstatic Page createPage(int everyPage, int :{?8rA5
C5m6{Oo+-
currentPage, int totalRecords){ v8p-<N)
everyPage = getEveryPage(everyPage); CJ0j2e/
currentPage = getCurrentPage(currentPage); 67Rsd2
int beginIndex = getBeginIndex(everyPage, % FW__SN$c
rld4uy}m
currentPage); X'4e)E3*O
int totalPage = getTotalPage(everyPage, ,":_=Tf.
j/_@~MJBt
totalRecords); iHhoNv`MR
boolean hasNextPage = hasNextPage(currentPage, [4B.;MS(
u6h"=l{
totalPage); +O>1Ed
boolean hasPrePage = hasPrePage(currentPage); &niROM,;K
7c$;-O
returnnew Page(hasPrePage, hasNextPage, v[WbQ5AND
everyPage, totalPage, )$V}tr!
currentPage, _UKH1qUd4
1~NXCIdF
beginIndex); ) '"@L7U
} WzYy<
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privatestaticint getEveryPage(int everyPage){ v`#T)5gl-
return everyPage == 0 ? 10 : everyPage; .PBma/w
W
} pv1J6
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privatestaticint getCurrentPage(int currentPage){ `P}T{!P+6
return currentPage == 0 ? 1 : currentPage; l1On .s
} h3Kv0^{
r!+-"hS!
privatestaticint getBeginIndex(int everyPage, int `r;e\Cp
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currentPage){ 4SSq5Ve<
return(currentPage - 1) * everyPage; (r,tU(
} d4<Ic#
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privatestaticint getTotalPage(int everyPage, int 4KF
1vw
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totalRecords){ @*jd.a`
int totalPage = 0; 7RNf)nz
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if(totalRecords % everyPage == 0) %toxZ}OP
totalPage = totalRecords / everyPage; mle"!*
else [I:D\)$<
totalPage = totalRecords / everyPage + 1 ; 2^N
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return totalPage; Q)x`'[3"7W
} ^pA|ubZ
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privatestaticboolean hasPrePage(int currentPage){ vy\;#X!
return currentPage == 1 ? false : true; -ZqN~5>j)
} A8Q1x/d(
-#T?C]}
privatestaticboolean hasNextPage(int currentPage, I;kKY
oyV@BHJO@
int totalPage){ m5Gt8Z 6a
return currentPage == totalPage || totalPage == TIlBT{A<
v
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0 ? false : true; vB(tpki|
} #7K&x.w$
. _JM3o}F
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} X&EcQ
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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。 Vh1{8'GQ
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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 8;>vgD
Fa78yY+6
做法如下: #MYhKySku
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g|_-O"l
Kj;gxYD>6
的信息,和一个结果集List: HH/bBM!
java代码: A\J|eSG'$
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]h8[b9$<")
/*Created on 2005-6-13*/ 7Z;bUMYtx
package com.adt.bo; F/;uN5{o
& %4x
import java.util.List; sp*_;h3'
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import org.flyware.util.page.Page; E?san;Ku
g2p/#\D\J
/** </0@7
* @author Joa !IlsKMZ
*/ a!YpSFr
publicclass Result { mD`v>L
*ZP$dQ
private Page page; cSy{*K{B
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private List content; :/'2@M
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/** 9fR`un)f}
* The default constructor y\7 -!
*/ vL~nJv
public Result(){ I g*68M<
super(); 2:0'fNXop
} =jZ}@L/+
Y(QLlJ*)/
/** Ia-`x/r*m
* The constructor using fields E'qGK T
* >g8H
* @param page v:0.
* @param content ~_^#/BnAl
*/ k fS44NV
public Result(Page page, List content){ 0 =#)-n
this.page = page; h6c0BmS{1
this.content = content; qzq_3^66
} #T_m|LN7
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/** .: ~);9kj
* @return Returns the content. RL0,QC)e#@
*/ GZgu1YR
publicList getContent(){ z/zUb``
return content; r}ZL{uWMW
} O!#yPSq?
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/** mD@#,B7A
* @return Returns the page. It.G-(
*/ fW^\G2Fk
public Page getPage(){ NUH;\*]8s
return page; ,{=pFs2
} KICy!
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/** tHgn-Dhzr
* @param content ge*(w{|x
* The content to set. +RLHe]9&
*/ \[</|]'[
public void setContent(List content){ =ZdP0l+V=k
this.content = content; p^1s9CM%
} /.!ytHw8
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/** *h59Vaoc
* @param page ~RdJP'YF-
* The page to set. -olD!zKS
*/ P~Ss\PT
publicvoid setPage(Page page){ 4LY
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this.page = page; -yKx"Q9F
} yhnhORSY;
} 6
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2. 编写业务逻辑接口,并实现它(UserManager, \va'>?#o1
('yBIb\ue
UserManagerImpl) yk
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java代码: g *}M;"
Imi;EHW
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/*Created on 2005-7-15*/ GF(<!PC
package com.adt.service; @lvvI<U
I9JiH,+
import net.sf.hibernate.HibernateException; o/Z
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import org.flyware.util.page.Page; tNsiokOm
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import com.adt.bo.Result; vU5a`0mH
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/** p9c`rl_N
* @author Joa ID+o6/V8
*/ r3.A!*!
publicinterface UserManager { M[aF3bbN
,+`1 /
public Result listUser(Page page)throws IK#W80y
"`Y.N$M`k
HibernateException; ~fL:pVp
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} Nr24Rv
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(sX=#<B%
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java代码: RY8Ot2DWi
3=r#=u5z
4dv5
/*Created on 2005-7-15*/ ){ywk
package com.adt.service.impl; $nX4!X
$F>
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import java.util.List; _," -25a
cE}y~2cH
import net.sf.hibernate.HibernateException; cL/6p0S
fb8"hO]s
import org.flyware.util.page.Page; 6]`XW0{C
import org.flyware.util.page.PageUtil; kGaK(^w
QL_~E;U
import com.adt.bo.Result; qIm?F>>@
import com.adt.dao.UserDAO; (?luV#{5
import com.adt.exception.ObjectNotFoundException; vAeh#V~#
import com.adt.service.UserManager; ]#)1(ZE
RPH]@
/** Ps<6 kQ(
* @author Joa !Db0r/_:G
*/ P(H,_7 4
publicclass UserManagerImpl implements UserManager { _FV<[x,nE8
tCkKJ)m
private UserDAO userDAO; vn5X]U"
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/** Z^P]-CB|6A
* @param userDAO The userDAO to set. :wlX`YW+e
*/ *RM?SE6;
publicvoid setUserDAO(UserDAO userDAO){ (wxdT6RVm\
this.userDAO = userDAO; RL0#WBR
} 014p = W
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/* (non-Javadoc) g[Tl#X7F
* @see com.adt.service.UserManager#listUser sY @S
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(org.flyware.util.page.Page) V1aWVLltj
*/ TDvUiJm
public Result listUser(Page page)throws 41\r7
BS
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HibernateException, ObjectNotFoundException { #g)$m}tv?
int totalRecords = userDAO.getUserCount(); HiTn 5XNf
if(totalRecords == 0) :g1C,M~
throw new ObjectNotFoundException 3Thb0\<"
#w2;n@7;X
("userNotExist"); gY)NPi}!`
page = PageUtil.createPage(page, totalRecords); qU ESN!
List users = userDAO.getUserByPage(page); a'sa{>
returnnew Result(page, users); `O:ecPD4M
} kpxWi=y
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} >]6inS9
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1J(` kQ)c
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>Ln/ )j
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ?]JTrv"zp
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询,接下来编写UserDAO的代码: Tt,<@U[/}
3. UserDAO 和 UserDAOImpl: P)hZFX
java代码: FlWgTn>
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6fP"I_c
/*Created on 2005-7-15*/ (%\vp**F
package com.adt.dao; )v1y
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b<]--\
import java.util.List; ~;m3i3D
/h/f&3'h
import org.flyware.util.page.Page; +`;YK7o
UODbT&&
import net.sf.hibernate.HibernateException; fpCkT [&m
}Mh@%2$
/** O<A$,<6 7
* @author Joa %/b3G*$W
*/ _;o)MTw|'
publicinterface UserDAO extends BaseDAO { ccLTA
O$'BJKj-4
publicList getUserByName(String name)throws ?*2DR:o>@
9qhX\, h
HibernateException; 5"x=kp>!d
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publicint getUserCount()throws HibernateException; <=]wh|D
o\n9(ao
publicList getUserByPage(Page page)throws ;S+UD~i[Bu
O8&