Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ynU20g
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *MZa|Xy
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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 y-#01Z
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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 KVZ-T1K
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分页支持类: S_dM{.!Z(,
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java代码: T6fm`uL&L
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package com.javaeye.common.util; 9a3mN(<
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import java.util.List; )lDmYt7me
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publicclass PaginationSupport { s>1Wjz2M
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publicfinalstaticint PAGESIZE = 30; |%c"Avc
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privateint pageSize = PAGESIZE; F<LRo}j"9Q
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privateList items; xmBGZ4f%
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privateint totalCount; XCUU(H
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privateint[] indexes = newint[0]; 4g^Xe-
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privateint startIndex = 0; Y]])Tq;h5
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public PaginationSupport(List items, int ,AEaW
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totalCount){ UTR`jXCg
setPageSize(PAGESIZE); M
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setTotalCount(totalCount); Z[?zaQ$
setItems(items); 1&#qq*{
setStartIndex(0); 1?,1EYT"
} )H|cri~D
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public PaginationSupport(List items, int 8D6rShx =
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totalCount, int startIndex){ l[u=_uaYl
setPageSize(PAGESIZE); _fE$KaP
setTotalCount(totalCount); $,
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setItems(items); zyPc<\HoK
setStartIndex(startIndex); $fFh4O4
} gjDxgNpa
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public PaginationSupport(List items, int g8L{xwx<
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totalCount, int pageSize, int startIndex){ EEdU\9DH(
setPageSize(pageSize); SKeX~uLz
setTotalCount(totalCount); %E*Q0/
setItems(items); o#9Q
setStartIndex(startIndex); /;clxtus
} ]@A}v\wa
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publicList getItems(){ iM(Q-%HP_
return items; r%412#
} t5;)<N`
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publicvoid setItems(List items){ Ze"m;T
this.items = items; @e:=
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} /lDei}
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publicint getPageSize(){ ne9-
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return pageSize; G;Py%8
} 4c9a"v
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publicvoid setPageSize(int pageSize){ 45.Vr[FS.
this.pageSize = pageSize; 8~ wP?
} X<mlaXwrA
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publicint getTotalCount(){ r<c&;*
return totalCount; P87Lo4Rd
} Q.} guI\
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publicvoid setTotalCount(int totalCount){ kcG_ n
if(totalCount > 0){ H7dT6`<~Y
this.totalCount = totalCount; k keDt+^
int count = totalCount / UAe8Ct=YJ
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pageSize; /X;/}fk
if(totalCount % pageSize > 0) Ld?'X=eQ
count++; vo>i36
indexes = newint[count]; XJe}^k
for(int i = 0; i < count; i++){ oe<DP7e
indexes = pageSize * a4\j.(w)$D
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} ,#U[)}im
}else{ W^YaC
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this.totalCount = 0; RmRPR<vGW
} $0XR<D
} )f,9 h
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publicint[] getIndexes(){ sf"vi i,1A
return indexes; t-Uo
} [,56oMd~
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publicvoid setIndexes(int[] indexes){ BlfadM;
this.indexes = indexes; XNJ3.w:R
} Zygu/M6
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publicint getStartIndex(){ +E-CsNAZ*"
return startIndex; $:RR1.Tv
} :}z`4S@b
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publicvoid setStartIndex(int startIndex){ otbr8&?-
if(totalCount <= 0) eY[kUMo
this.startIndex = 0; j]C}S*`"
elseif(startIndex >= totalCount) 'P)c'uqd#
this.startIndex = indexes 1pAcaJzf
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[indexes.length - 1]; HZqk)sN
elseif(startIndex < 0) `j8pgnY>5~
this.startIndex = 0; Cy dV$!&mP
else{ '0w</g
this.startIndex = indexes i>O8q%BnJ
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[startIndex / pageSize]; J`[gE`d
} 83J63Xa
} SHT`
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publicint getNextIndex(){ [}!0PN?z~A
int nextIndex = getStartIndex() + 6aLRnH"Ud
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pageSize; 0Wj,=9q
if(nextIndex >= totalCount) ]>B4
return getStartIndex(); 8([ MR
else +;-ZU
return nextIndex; 0:`*xix
} QP/ZD|/ t1
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publicint getPreviousIndex(){ V*DD U]0k
int previousIndex = getStartIndex() - &0i$Y\g
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pageSize; mLx=Zes:.
if(previousIndex < 0) bYO['ORr@
return0; !jvl"+_FV
else n?U^vK_
return previousIndex; U(Tl$#Bt
} n?;h-KKO:
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} $[Q;{Q
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抽象业务类 !_FTy^@c2
java代码: nxB[To*P
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/** `~z[Hj=2
* Created on 2005-7-12 zhJ0to[%?
*/ (%OZ `?`
package com.javaeye.common.business; "j&'R#$&d
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import java.io.Serializable; xS>vmnW
import java.util.List; tW
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import org.hibernate.Criteria; S*gm[ZLQ
import org.hibernate.HibernateException; #^BttI
import org.hibernate.Session; icb*L ~qm
import org.hibernate.criterion.DetachedCriteria; !9.FI{W
import org.hibernate.criterion.Projections; Ii&p v
import {,u})U2
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org.springframework.orm.hibernate3.HibernateCallback; OE}FZCXF
import xZ6x`BET-
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org.springframework.orm.hibernate3.support.HibernateDaoS \KzH5 ?
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upport; 7377g'jL
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import com.javaeye.common.util.PaginationSupport; r6kJV4I=re
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public abstract class AbstractManager extends ANNVE},
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HibernateDaoSupport { ^Ua6.RH8
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privateboolean cacheQueries = false; PfyJJAQ[
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privateString queryCacheRegion; \Z,{De%
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publicvoid setCacheQueries(boolean `a!9_%|8
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cacheQueries){ MB7*AA;
this.cacheQueries = cacheQueries; -Lu&bVt<>
} R}cNhZC
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publicvoid setQueryCacheRegion(String jRd$Vt
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queryCacheRegion){ !/!ga)Y
this.queryCacheRegion = _6V1oe2
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queryCacheRegion; ]<C]`W2{
} c#>(8#'.U
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publicvoid save(finalObject entity){ $dXx@6fP
getHibernateTemplate().save(entity); -jy0Kl/p
} T=)qD2?
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publicvoid persist(finalObject entity){ ".%d{z}vz
getHibernateTemplate().save(entity); d#]hqy
} .izq}q*P
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publicvoid update(finalObject entity){ ZX64kk+
getHibernateTemplate().update(entity); fIl!{pv[
} jw9v&/-
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publicvoid delete(finalObject entity){ GGhk~H4OP
getHibernateTemplate().delete(entity); i#hFpZ6u
} SJ<v< B
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publicObject load(finalClass entity, fBctG~CJH
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finalSerializable id){ 0#Lmajs
return getHibernateTemplate().load aZCq{7Xs
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(entity, id); XL^05
} D%nd7
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publicObject get(finalClass entity, IhBc/.&RL
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finalSerializable id){ ~!5=o{wy
return getHibernateTemplate().get &e@)yVLL
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(entity, id); * 70ZAo4
} >Rd~-w)!|
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publicList findAll(finalClass entity){ )0iN2L]U;
return getHibernateTemplate().find("from .1jiANY
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" + entity.getName()); BjsT 9?6W/
} qSB&Q0T
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publicList findByNamedQuery(finalString (nt`8 0
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namedQuery){ C[G+SA1&W
return getHibernateTemplate UUlz3"`
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().findByNamedQuery(namedQuery); $q)YC.5$
} 4minzrKM\
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publicList findByNamedQuery(finalString query, Mh4MaLw
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finalObject parameter){ j}eb
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return getHibernateTemplate L;%w{,Ji
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().findByNamedQuery(query, parameter); jh)@3c
} (+epRC
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publicList findByNamedQuery(finalString query, ZQ_6I}i")
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finalObject[] parameters){ Ly+UY.v"
return getHibernateTemplate R-S<7Q3E0=
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().findByNamedQuery(query, parameters); xBVOIc[4(
} z6C(?R
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publicList find(finalString query){ TXmS$q
return getHibernateTemplate().find 5b7(^T^K
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(query); 'UIFP#GtFO
} #BUq;5
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publicList find(finalString query, finalObject gCb+hQq\
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parameter){ M% \T5
return getHibernateTemplate().find DFK@/.V
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(query, parameter); &sWr)>vs
} p8~lGuH
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public PaginationSupport findPageByCriteria )N&SrzqTK
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(final DetachedCriteria detachedCriteria){ FN-/~Su~J
return findPageByCriteria $u!(F]^
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); U`ttT5;
} Lj<TzPzg*
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public PaginationSupport findPageByCriteria M?eP1v:<+G
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(final DetachedCriteria detachedCriteria, finalint G+8)a$?v
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startIndex){ mvEhP{w
return findPageByCriteria Uz^N6q
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(detachedCriteria, PaginationSupport.PAGESIZE, C
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startIndex); K
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} 6DHK&<=D8
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public PaginationSupport findPageByCriteria mrP48#Y+l
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(final DetachedCriteria detachedCriteria, finalint .[O{,r
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pageSize, szsVk#p
finalint startIndex){ a|7C6#iz$
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ ?$f.[;mh
publicObject doInHibernate Jw;~ $
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(Session session)throws HibernateException { ]<>cjk.ya
Criteria criteria = =6[.||9
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detachedCriteria.getExecutableCriteria(session); SH?McBxS
int totalCount = #Q8_:dPY
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((Integer) criteria.setProjection(Projections.rowCount %R c#/y
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()).uniqueResult()).intValue(); 1&=)Bxg4
criteria.setProjection Ek)drt7cy
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(null); OTXZdAv
List items = Ib# -M;{
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criteria.setFirstResult(startIndex).setMaxResults 3x+lf4"
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(pageSize).list(); bw P=f.
PaginationSupport ps = ,>a!CnK=
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new PaginationSupport(items, totalCount, pageSize, , _e[P
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startIndex); P8z%*/
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return ps; MbRTOH
} 8_('[89m
}, true); u9hd%}9Qd?
} yJ $6vmQ
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public List findAllByCriteria(final Jl~ *@0(
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DetachedCriteria detachedCriteria){ zC2:c"E
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return(List) getHibernateTemplate Dp([r
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().execute(new HibernateCallback(){ }(nT(9|
publicObject doInHibernate h3?>jE=H
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(Session session)throws HibernateException { u<ed O+
Criteria criteria = WO qDW~
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detachedCriteria.getExecutableCriteria(session); g<j)
return criteria.list(); Z =+Z96
} xe!bfzU
}, true); JsJP%'^/R
} MGR:IOTa
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public int getCountByCriteria(final '=_(fa,
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DetachedCriteria detachedCriteria){ ~[ufL25K
Integer count = (Integer) ` 2W^Ui,4
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getHibernateTemplate().execute(new HibernateCallback(){ E_ns4k#uG
publicObject doInHibernate <fUo@]Lv
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(Session session)throws HibernateException { U~x]2{}
Criteria criteria = DDeU:
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detachedCriteria.getExecutableCriteria(session); #Z%"
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return hq=;ZI
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criteria.setProjection(Projections.rowCount Hl$W+e|tj
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()).uniqueResult(); .?:*0
} ?M4o>T%p "
}, true); #t
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return count.intValue(); ]fM|cN8(zM
} ;{ifLI0#
} s)1-xA{'.
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用户在web层构造查询条件detachedCriteria,和可选的 =]7o+L4
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ALMsF2H
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PaginationSupport的实例ps。 T9nb ~P[
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ps.getItems()得到已分页好的结果集 S{=5nR9 j
ps.getIndexes()得到分页索引的数组 /WN YS
ps.getTotalCount()得到总结果数 `_\KN_-%Vu
ps.getStartIndex()当前分页索引 }S> 4.8
ps.getNextIndex()下一页索引 [H h-F#|R
ps.getPreviousIndex()上一页索引 b>-DX
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Aw#<: 6-
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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 FZi@h
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一下代码重构了。 CRb*sfKDL
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我把原本我的做法也提供出来供大家讨论吧: 8b/$Qp4d
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首先,为了实现分页查询,我封装了一个Page类: QEyL/#Q
java代码: 2"ax*MQH<^
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/*Created on 2005-4-14*/ (nqry[g&
package org.flyware.util.page; *ID=X!v
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/** kdNo<x1o
* @author Joa FGV
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* T[\1=h]
*/ HI8mNX3 "j
publicclass Page { '`jGr+K,wU
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/** imply if the page has previous page */ D3o,2E(o
privateboolean hasPrePage; > 80{n8
/!5Wd(:
/** imply if the page has next page */ ] ?DU8
privateboolean hasNextPage; m{q'RAw
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/** the number of every page */ 5JzvT JMx
privateint everyPage; n>'(d*[e&
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/** the total page number */ KFrsXf
privateint totalPage; $)M3fZ$#
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/** the number of current page */ iH(7.?.r
privateint currentPage; qAjtvc2
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/** the begin index of the records by the current {$frR "K
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query */ o 4F'z
privateint beginIndex; MPB[~#:
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/** The default constructor */ `J.,dqGb
public Page(){ Sdq}?- &Sa
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} t'44X
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/** construct the page by everyPage w"R<8e=
* @param everyPage %-n)L
* */ Xh"9Bcjf
public Page(int everyPage){ 'cO8& |
this.everyPage = everyPage; p(F@lL-
} b<W\#3~G
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/** The whole constructor */ i~u4v3r=
public Page(boolean hasPrePage, boolean hasNextPage, 0%f}Q7*R
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int everyPage, int totalPage, _}R$h=YD
int currentPage, int beginIndex){ Z
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this.hasPrePage = hasPrePage; YSnh2 Bq
this.hasNextPage = hasNextPage; J9T2 p\5
this.everyPage = everyPage; 7@c!4hmrU
this.totalPage = totalPage; Myc-lCE
this.currentPage = currentPage; P+CV4;Xz
this.beginIndex = beginIndex; p$Tk;;wm
} j97+'AKX
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/** %1#\LRA(
* @return '{d_q6,%
* Returns the beginIndex. ,3:f4e\<
*/ SdH=1zBc
publicint getBeginIndex(){ s$fM,l:!
return beginIndex; ";/]rwHa)
} }c,b]!:
TEV DES
/** #0AyC.\
* @param beginIndex )\+Imn
* The beginIndex to set. fJ}e
*/ i c{I
publicvoid setBeginIndex(int beginIndex){ :w8{BIUN)
this.beginIndex = beginIndex; S
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} m
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/**
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* @return A'EI1_3{
* Returns the currentPage. V!:!c]8F
*/ e:G~P
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publicint getCurrentPage(){ >.wZEQ6QK
return currentPage; 3 Zp<#
} <#0i*PM_
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/**
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* @param currentPage UBd+,]"f
* The currentPage to set. 0AM_D >fH
*/ FVXsu!R
publicvoid setCurrentPage(int currentPage){ h8V*$
this.currentPage = currentPage; ,:Px(=d4
} Yn?beu'
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/** u7e$Mq
* @return VxY]0&sq
* Returns the everyPage. 3,p!Fun:r
*/ Z
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publicint getEveryPage(){ Fo3*PcUv
return everyPage; *~8F.cx
} O?vh]o
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/** qGX@mo({
* @param everyPage h3F559bw/<
* The everyPage to set. $:s@nKgnD~
*/ bidFBldKl
publicvoid setEveryPage(int everyPage){ bd/A0i?C
this.everyPage = everyPage; aR2N,<Cp5
} SS/vw%
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/** b`e_}^,c
* @return Ug*B[q/
* Returns the hasNextPage. cyNE}
*/ ~ZafTCa;
publicboolean getHasNextPage(){ jI,[(Z>
return hasNextPage; %;&lVIU0
} &S="]*Z
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._
/** ZvyZ5UA
* @param hasNextPage B~:yM1f@u4
* The hasNextPage to set. 4j3q69TZR
*/ 'bbw0aB4
publicvoid setHasNextPage(boolean hasNextPage){ bg~CV&]M
this.hasNextPage = hasNextPage; hP:>!KJ
} |?KYY0
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/** kw59`z Es
* @return ,X/j6\VBO
* Returns the hasPrePage. :s_o'8z7L
*/ 9swHa
publicboolean getHasPrePage(){ qX}3}TL
return hasPrePage; 2>jk@~Z1:u
} +xuv+mo
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/** /J^dzvH
* @param hasPrePage 23CvfP
* The hasPrePage to set. !WXV1S
*/ ,OlS>>,
publicvoid setHasPrePage(boolean hasPrePage){ +VVn@=&?
this.hasPrePage = hasPrePage; ">T\]V$R
} -+ F,L8
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/** !=S?*E +j)
* @return Returns the totalPage. 'n h^;
* `NhG|g
*/ pbKmFweq
publicint getTotalPage(){ v,n 8$,
return totalPage; :G6CWE
} Fepsa;\sU
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/** XrUI[ryE
* @param totalPage .?:#<=1
* The totalPage to set. Q>L(=j2t
*/ x((u
publicvoid setTotalPage(int totalPage){ yoGG[l2k>s
this.totalPage = totalPage; l|+$4 Nb2
} O+&;,R:
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} r]6+&K
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2RZa}
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 wMkHx3XD
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个PageUtil,负责对Page对象进行构造: a6zWg7 PN
java代码: 5ppr;QaB
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/*Created on 2005-4-14*/ @@@}FV&
package org.flyware.util.page; !{,2uQXe
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e
import org.apache.commons.logging.Log; ?9xWTVa8
import org.apache.commons.logging.LogFactory; 0(o2<d7
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/** V9/2y9u
* @author Joa ,#N}Ni:
* ~NE`Ad.G
*/ e
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publicclass PageUtil { @ddCVxd
@D[+@N
privatestaticfinal Log logger = LogFactory.getLog &@xm< A\S
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(PageUtil.class); i~E0p
,
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/** fhn$~8[_A
* Use the origin page to create a new page 6 _V1s1F
* @param page }#tbK 2[
* @param totalRecords dB~A4pZa
* @return ;^JMX4[
*/ 3\]j4*i!
publicstatic Page createPage(Page page, int cRs\()W
$$Tf1hIg
totalRecords){ DI(X B6
return createPage(page.getEveryPage(), .|CoueH
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page.getCurrentPage(), totalRecords); VN09g&
} Qn$YI9t
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/** Dy5&-yk
* the basic page utils not including exception e{5O>RO
V(;T{HW&
handler ouyZh0G
* @param everyPage 'h;qI&
* @param currentPage w^cQL%
* @param totalRecords %<+Ku11
* @return page oR%cG"y
*/ HoX={^aG%
publicstatic Page createPage(int everyPage, int S
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currentPage, int totalRecords){ >mtwXmI
everyPage = getEveryPage(everyPage); 'k}w|gNB
currentPage = getCurrentPage(currentPage); IR3+BDE)>
int beginIndex = getBeginIndex(everyPage, N`d%4)|{
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currentPage); 'A3*[e|OS
int totalPage = getTotalPage(everyPage, ]N\D^`iQ
:RDk{^b)
totalRecords); 5w~ 0Q
boolean hasNextPage = hasNextPage(currentPage, 1fV)tvU$
OZz/ip-!lc
totalPage); Zcw<USF8
boolean hasPrePage = hasPrePage(currentPage); fHwS12SB
OK-*TPrc
returnnew Page(hasPrePage, hasNextPage, *yHz#u'
everyPage, totalPage, R4 b!?}d
currentPage, *Cp:<Mnd
f fI=Bt]t
beginIndex); XL44pE
m
} Pxkh;:agD
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privatestaticint getEveryPage(int everyPage){ (QojIdHt
return everyPage == 0 ? 10 : everyPage; 9Y:.v@:}0
} 6shN%
;P}007;
privatestaticint getCurrentPage(int currentPage){ X%og}Cfi
return currentPage == 0 ? 1 : currentPage; JoG(Nk]
} E:B<_
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privatestaticint getBeginIndex(int everyPage, int XR<g~&h
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currentPage){ N_FjEZpX
return(currentPage - 1) * everyPage; =b"{*Heuw
} J0f!+]~G3
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privatestaticint getTotalPage(int everyPage, int 0dsL%G~/N
xFIzq
totalRecords){ jUZ$vyT
int totalPage = 0; ;*+H&
t+pA9^$[`
if(totalRecords % everyPage == 0) `WMU'ezF
totalPage = totalRecords / everyPage; Z;tWV%F5
else ~$//4kES
totalPage = totalRecords / everyPage + 1 ; S|KUh|=Q
SY:ISzB}
return totalPage; }Q\+w,pJgN
} YUTh*`1k<
pVzr]WFx
privatestaticboolean hasPrePage(int currentPage){ BW3Q03SW6
return currentPage == 1 ? false : true; b&Laxki
} '~7zeZ'
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privatestaticboolean hasNextPage(int currentPage, h3GUFiZ.
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int totalPage){ e]dFNunFq0
return currentPage == totalPage || totalPage == Nw"?~"bo
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0 ? false : true; uvR l`"Y
}
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}
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 2qV oe}F
}}rp/16
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 j0Cj&x%qF}
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做法如下: oxUBlye
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 py%~Qz%
'R-g:X\{
的信息,和一个结果集List: f`}/^*D
java代码: amX1idHo^
1D!MXYgm1b
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/*Created on 2005-6-13*/ ?'H+u[1.
package com.adt.bo; l&kZ6lZ
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import java.util.List; W4P+?c>'2
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import org.flyware.util.page.Page; R>5Xv%R
sX}#L
/** ([^f1;ncm
* @author Joa [}l 90 lP
*/ LylCr{s7
publicclass Result { Xx2t0AIB
!) `*e>]x
private Page page; yc`3)
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private List content; q
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/** \L}7.fkb8
* The default constructor l,3,$
*/ R[*n3
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public Result(){ 5}! 36SO\
super(); 4pelIoj
} MR5[|kHJT
9:=:P>
/** 1;B&R89}
* The constructor using fields Bc-/s(/Eq
* kkMChe};5
* @param page m6}_kzFz
* @param content {.;qz4d`
*/ hM>.xr
public Result(Page page, List content){ 8TU(5:xJo
this.page = page; %~>-nqS
this.content = content; E`C!q
X>
} Oz&*A/si+3
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/** knpdECq&k
* @return Returns the content. ~v:IgS
*/ ufw[Ei$I:
publicList getContent(){ s5Wb iOF
return content; F!4V!VWA}
} (#)XRm{t
N>Uxq&)!
/** |;d#k+/;
* @return Returns the page. tTubW=H
*/ CBpwtI>p
public Page getPage(){ iE_[]Vgc
return page; ma<uXq
} 6R$Yh0%
c6h+8QS
/** ;+#Nb/M
* @param content 7`^Y*:(
* The content to set. $"MVr5q6
*/ -XK;B--c
public void setContent(List content){ 3u+i
this.content = content; EAxdF
u
} WB<MU:.Vc
gf9U<J#&C
/** S;D]ym
* @param page bGy|T*@
* The page to set. @t*D<B$
*/ /iAhGY
publicvoid setPage(Page page){ $e,r>tgD
this.page = page; j+q)
} cD)9EFo
} `
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2. 编写业务逻辑接口,并实现它(UserManager, N[fwd=$\#
y9LO;{(
UserManagerImpl) M&gi$Qs[E
java代码: T/ eX7p1
WSv%Rxr8L
$;~YgOVZ5
/*Created on 2005-7-15*/ P|p
X
F~
package com.adt.service; =K|#5p`
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import net.sf.hibernate.HibernateException; N^PkSf[)h5
@$;8k }
import org.flyware.util.page.Page; =VT\$
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import com.adt.bo.Result; 6U$e;cr6
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/** ]>*VEe}hJ
* @author Joa |-S+ x]9
*/ 'O.f}m SS
publicinterface UserManager { &
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public Result listUser(Page page)throws kt\,$.v8
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HibernateException; jENC1T(
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} ?E}gm>
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java代码: 3hje
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/*Created on 2005-7-15*/ ka ;=%*7T
package com.adt.service.impl; JRZp'Ln
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import java.util.List; q8;MPXSG3
4`fV_H.8
import net.sf.hibernate.HibernateException; k'PvQl"I
a^E>LJL
import org.flyware.util.page.Page; Sl'$w4s
import org.flyware.util.page.PageUtil; eOkiB!G.
nHQ*#&$
import com.adt.bo.Result; ~RwoktO
import com.adt.dao.UserDAO; ) j&khHD
import com.adt.exception.ObjectNotFoundException; )C{20_
import com.adt.service.UserManager; *tk=D sRW
b!Nr
/** a~LdcUYs
* @author Joa h(J$-SUs
*/ C&%NO;Ole
publicclass UserManagerImpl implements UserManager { gyV`]uqG
7N@[Rtv
private UserDAO userDAO; 9V&+xbR&
[wiB1{/Ls.
/** UL#:!J/34
* @param userDAO The userDAO to set. 2Oyw#1tdn
*/ ["Tro;K#
publicvoid setUserDAO(UserDAO userDAO){ 1@|%{c&+9
this.userDAO = userDAO; m']$)Iqw
} }u$c*}
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/* (non-Javadoc) GM1.pVb
* @see com.adt.service.UserManager#listUser n9k
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(org.flyware.util.page.Page) OI78wG
*/ j!oX\Y-: &
public Result listUser(Page page)throws /FpPf[
O@W/s!&lFa
HibernateException, ObjectNotFoundException { ZWzr8oY)
int totalRecords = userDAO.getUserCount(); yV(9@lj3;
if(totalRecords == 0) j8bA"r1
throw new ObjectNotFoundException S~ S>62
"^ BA5
("userNotExist"); m_Z(osoE#W
page = PageUtil.createPage(page, totalRecords); h&v].l
List users = userDAO.getUserByPage(page); XeY[;}9
returnnew Result(page, users); {D|ST2:E
} X&5N89
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} G %\/[
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 c;-NRvVb
FwHqID_!:l
询,接下来编写UserDAO的代码: "lC>_A
3. UserDAO 和 UserDAOImpl: "Ms{c=XPK
java代码: ? u".*!%
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