Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?+P D?c7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /gH[|d
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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 [`n)2}
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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 :aHLr[%Mz
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分页支持类: ;h~v,h
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java代码: ']&rPvkL
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package com.javaeye.common.util; Lk8[fFa4
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import java.util.List; ."u
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publicclass PaginationSupport { h_y;NB(w
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publicfinalstaticint PAGESIZE = 30; =O
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privateint pageSize = PAGESIZE; P1_ZGeom*
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privateList items; 7=@3cw
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privateint totalCount; X/qLg+X
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privateint[] indexes = newint[0]; `^mY*Cb e
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privateint startIndex = 0; Q<O(Ix
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public PaginationSupport(List items, int &YOks.k
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totalCount){ "CTK%be{q/
setPageSize(PAGESIZE); ym*oCfu=
setTotalCount(totalCount); )|N_Q}
setItems(items); V`& O`
setStartIndex(0); i XPe
} e-EY]%JO
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public PaginationSupport(List items, int lF#p1H>\
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totalCount, int startIndex){ lL;SP&
setPageSize(PAGESIZE); J/xbMMb
setTotalCount(totalCount); 3/s" ;Kg,
setItems(items); Oe)B.{;Ph
setStartIndex(startIndex); \r`><d
} ;7*R ;/
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public PaginationSupport(List items, int #`o]{UfW
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totalCount, int pageSize, int startIndex){ = P@j*ix
setPageSize(pageSize); |y$8!*S~(
setTotalCount(totalCount); yKB&][)&
setItems(items); lO/?e!$
setStartIndex(startIndex); :cA%lKg
} ,SG-{
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publicList getItems(){ ~\khwNA
return items; O.z\
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} U'p-Ko#
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publicvoid setItems(List items){ L_O*?aaZ
this.items = items; tDQuimYu7
} ]9PQKC2&
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publicint getPageSize(){ VdOcKP.
return pageSize; Op5S'
} ?2nF1>1
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publicvoid setPageSize(int pageSize){ }8eu 9~
this.pageSize = pageSize; {?RVw`g&f
} R5& R~1N
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publicint getTotalCount(){ <! Z06
return totalCount; %3Tz%>n
} ;"w?@ELE
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publicvoid setTotalCount(int totalCount){ \(`8ng]vs
if(totalCount > 0){ 3L^]J}|
this.totalCount = totalCount; @/W~lJ!e
int count = totalCount / _?oofE:{
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pageSize; Wy.^1M/n>~
if(totalCount % pageSize > 0) @(W{_ mw
count++; >e"vPW*[
indexes = newint[count]; g T{WH67u
for(int i = 0; i < count; i++){ 6-Id{m x
indexes = pageSize * k9m9IE"9=$
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} Xrr3KQaK&
}else{ f!Mx +ky
this.totalCount = 0; o2rL&
} S!8gy,7<J
} G$A=T u~
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publicint[] getIndexes(){ v%@)I_6[P
return indexes; e#odr{2#4u
} *!MMl]gU?
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publicvoid setIndexes(int[] indexes){ h.jO3q
this.indexes = indexes; s8.SEk|pB
} SLU$DW;t
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publicint getStartIndex(){ R3|r`~@@
return startIndex; X'J!.Jj
} 6~^ M<E
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publicvoid setStartIndex(int startIndex){ *CCh\+S7m
if(totalCount <= 0) VT [TE
this.startIndex = 0; H b?0?^#
elseif(startIndex >= totalCount) bbs'>D3
this.startIndex = indexes :Z&<5
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[indexes.length - 1]; CB^.N>'
elseif(startIndex < 0) 2 9#jKh
this.startIndex = 0; N?2C*|%f
else{ u';9zk/$
this.startIndex = indexes T#GTNk!v
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[startIndex / pageSize]; =K<`nF0w
} UY(\T8
} F R(k==pZ
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publicint getNextIndex(){ v>/_U
int nextIndex = getStartIndex() + B!1h"K5.($
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pageSize; +~$pkxD"
if(nextIndex >= totalCount) G^Va$ike
return getStartIndex(); %JL P=(
else hsHbT^Qm
return nextIndex; |B
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} *RM 3_
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publicint getPreviousIndex(){ ]
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int previousIndex = getStartIndex() - N/78Ub
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pageSize; uN4e n,
if(previousIndex < 0) ]d~2WX Y
return0; Rga
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else .: k6Kg
return previousIndex; G8&/Ic
} ^^B~v<uK
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} I-^C6~
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抽象业务类 Wv||9[Rd
java代码: &y&HxV
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/** sa TS8p z
* Created on 2005-7-12 ^yX >^1
*/ c~+KrWbZ~
package com.javaeye.common.business; )=VAEQhL-
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import java.io.Serializable; 2ZEDyQM
import java.util.List; i1ScXKO
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import org.hibernate.Criteria; GOOm] ]I
import org.hibernate.HibernateException; {y'4&vt<~
import org.hibernate.Session; *-*SCA`E^=
import org.hibernate.criterion.DetachedCriteria; [RF 6mWQ
import org.hibernate.criterion.Projections; ~@DdN5
import !t+ 3DMPn
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org.springframework.orm.hibernate3.HibernateCallback; Lg~ll$
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import ~=Q^]y,
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org.springframework.orm.hibernate3.support.HibernateDaoS Sm{> 8e}UE
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upport; R.cR:fA
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import com.javaeye.common.util.PaginationSupport; ]!j%Ad
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public abstract class AbstractManager extends JT&RaFX
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HibernateDaoSupport { _u]%K-_
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privateboolean cacheQueries = false; n(`|:h"
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privateString queryCacheRegion; "8R
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publicvoid setCacheQueries(boolean fW[ .Q0
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cacheQueries){ FA+"t^q
this.cacheQueries = cacheQueries; 7]9,J(:Ed
} ac\( [F-
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publicvoid setQueryCacheRegion(String o7s!ti\G
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queryCacheRegion){ +I?k8',pi
this.queryCacheRegion = Qj'Ik`o
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queryCacheRegion; F0~<p[9Nx
} }'*6 A
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publicvoid save(finalObject entity){ :yRv:`r3Lt
getHibernateTemplate().save(entity); 2$ &B@\WY
} lu8*+.V
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publicvoid persist(finalObject entity){ A $ ]s{`
getHibernateTemplate().save(entity); k?$I4&|5Nt
} Cv}^]_`Q
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publicvoid update(finalObject entity){ a{@}vZx>3
getHibernateTemplate().update(entity); |B^Mj57DO
} tHAe
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publicvoid delete(finalObject entity){ 2v2XU\u{t
getHibernateTemplate().delete(entity); tt#dO@G#Fe
} 6oKdw|(Q#
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publicObject load(finalClass entity, VZq~ -$
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finalSerializable id){ SZEi+CRs0
return getHibernateTemplate().load .`Q^8|$-K
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(entity, id); wJNm}Wf
} Ij$C@hH
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publicObject get(finalClass entity, *AYq:n6
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finalSerializable id){ '_^T]fr}
return getHibernateTemplate().get z:@:B:E
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(entity, id); Zazff@O *
} ^5.XQ0n
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publicList findAll(finalClass entity){ :W5W
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return getHibernateTemplate().find("from &!OEd]
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" + entity.getName()); ,2^4"gIl
} eZaSV>27
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publicList findByNamedQuery(finalString iaCV8`&q%
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namedQuery){ \+l*ZNYM3
return getHibernateTemplate Yj#tF}nPC
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().findByNamedQuery(namedQuery); jj1\oyQ8
} '3Lu_]I-
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publicList findByNamedQuery(finalString query, ICvV}%d
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finalObject parameter){ =E5bM_P<K
return getHibernateTemplate __2<v?\
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().findByNamedQuery(query, parameter); Qr9;CVW
} y TD4![
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publicList findByNamedQuery(finalString query, UXs)$
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finalObject[] parameters){ @phVfP"M
return getHibernateTemplate fEX=csZ86
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().findByNamedQuery(query, parameters); ])o{!}QUl\
} )@X0'X<
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publicList find(finalString query){ +a3E=GJ
return getHibernateTemplate().find Jsysk $R
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(query); \gk.[={^P
} -}9^$}PR
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publicList find(finalString query, finalObject *y!O\-\S#>
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parameter){ /\c'kMAW!
return getHibernateTemplate().find O=A2QykV(
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(query, parameter); 4P&2Z0
} "FWx;65CR
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public PaginationSupport findPageByCriteria RqtBz3v
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(final DetachedCriteria detachedCriteria){ U}RBgPX!
return findPageByCriteria &ASR2J
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); #cu{AdK
} _cX}!d!j
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public PaginationSupport findPageByCriteria y:W6;R
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(final DetachedCriteria detachedCriteria, finalint ];OvV ,*
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startIndex){ T&?g)
return findPageByCriteria -GAF>
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(detachedCriteria, PaginationSupport.PAGESIZE, G}fBd
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startIndex); +e-F`k
} x#J9GP.
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public PaginationSupport findPageByCriteria 94rSB}b.O
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(final DetachedCriteria detachedCriteria, finalint 9{*{Ba
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pageSize, ;!MQ@Fi^
finalint startIndex){ %.Ma_4o
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return(PaginationSupport) D%p*G5Bg3
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate iT>u&0B-
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(Session session)throws HibernateException { x
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Criteria criteria = :\\NK/"
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detachedCriteria.getExecutableCriteria(session); fQJ`&9m*BF
int totalCount = H648 [H[k
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((Integer) criteria.setProjection(Projections.rowCount <+_XGOt0<
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()).uniqueResult()).intValue(); D\acA?d`
criteria.setProjection {A/r)
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(null); 2R[v*i^S
List items = a!9'yc
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criteria.setFirstResult(startIndex).setMaxResults C/e.BXA
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(pageSize).list(); J~m$7T3Af
PaginationSupport ps = m,k0 h%
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new PaginationSupport(items, totalCount, pageSize, ipu!{kJ
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startIndex); 42NfD/"g+s
return ps; L ;L:
} c/|{yp$Ga>
}, true); !l (Vk
} T$5wH )<
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public List findAllByCriteria(final 2~kx3` Q
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DetachedCriteria detachedCriteria){ )9YDNVo*-
return(List) getHibernateTemplate FDMQLx f
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().execute(new HibernateCallback(){ 0D(8-H
publicObject doInHibernate Lce,]z\_
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(Session session)throws HibernateException { xMJ-=
Criteria criteria = \@gV$+{9
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detachedCriteria.getExecutableCriteria(session); (a[BvJf
return criteria.list(); 5 pCicwea#
} <=4$.2ym
}, true); uY]';OtG
} .g#}2:3
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public int getCountByCriteria(final MntmBj-T
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DetachedCriteria detachedCriteria){ oGcgd$%ZB
Integer count = (Integer) _Xf1FzF+a
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getHibernateTemplate().execute(new HibernateCallback(){ N[_T3(
publicObject doInHibernate 7{#p'.nc5
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(Session session)throws HibernateException { q8{Bx03m6
Criteria criteria = imM!Me 0TE
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detachedCriteria.getExecutableCriteria(session); 1=5"j]0hY
return +^AdD8U
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criteria.setProjection(Projections.rowCount /TMVPnvz.
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()).uniqueResult(); q[U pP`Z%
} v;(cJ,l
}, true); V IzIl\<aM
return count.intValue(); C*YQ{Mz(f
} (JbRhcg
} +6WjOcu
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用户在web层构造查询条件detachedCriteria,和可选的 $<-a>~^Tp
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 rmjuNy=(
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PaginationSupport的实例ps。 ,a5q62)q
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ps.getItems()得到已分页好的结果集 K_MEd1l
ps.getIndexes()得到分页索引的数组 g2f"tu_/%
ps.getTotalCount()得到总结果数 (Yy#:r;U
ps.getStartIndex()当前分页索引 +Z"Wa0wA
ps.getNextIndex()下一页索引 dpW`e>o
ps.getPreviousIndex()上一页索引 upMs yLp(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #66i!}
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 (cVIjo+::
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一下代码重构了。 gbdzS6XW~
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我把原本我的做法也提供出来供大家讨论吧: KcT(/!
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首先,为了实现分页查询,我封装了一个Page类: R*6TS"aL
java代码: / :$WOQ
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/*Created on 2005-4-14*/ Ktk?(49
package org.flyware.util.page; .nY}_&
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/** 4l0>['K&{
* @author Joa >FeCa
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* 56Lxr{+X
*/ !~zn*Hm
publicclass Page { O
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/** imply if the page has previous page */ o"qxR'V
privateboolean hasPrePage; O}C*weU
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/** imply if the page has next page */ 5xc e1[
privateboolean hasNextPage; whN<{AG
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/** the number of every page */ CL7_3^2qI
privateint everyPage; \6AM?}v
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/** the total page number */ K7s[Fa6J
privateint totalPage; W
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/** the number of current page */ odL*_<Z
privateint currentPage; E|-oUzt
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/** the begin index of the records by the current {yNeZXA>
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query */ [m! P(o
privateint beginIndex; e>_a
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/** The default constructor */ otaRA
public Page(){ Ho#nM_ q
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} `)$G}7cRUH
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/** construct the page by everyPage n+
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* @param everyPage n3?
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* */ uju'Bs7
public Page(int everyPage){ |J@
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this.everyPage = everyPage; P\@kqf~pC
} uNEl]Q]<e]
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/** The whole constructor */ ;P<h9(
public Page(boolean hasPrePage, boolean hasNextPage, UOj*Gt&
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int everyPage, int totalPage, pcIS}+L
int currentPage, int beginIndex){ }x#e.}hf&
this.hasPrePage = hasPrePage; JS03BItt
this.hasNextPage = hasNextPage; XlX t,
this.everyPage = everyPage; J>M 9t%f@
this.totalPage = totalPage; fJNK@F
this.currentPage = currentPage; leF!Uog
this.beginIndex = beginIndex; g3Q;]8Y&
} hKg +A
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/** W2%@}IDm
* @return +mft
* Returns the beginIndex. q`8
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*/ HP7~Zn)c
publicint getBeginIndex(){ 0`V=x+*,
return beginIndex; 0i5S=L`j
} $U/lm;{%
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/** #Mk3cp^Yl
* @param beginIndex E>/~:
* The beginIndex to set. 5MYdLAjV
*/ #""T>+
publicvoid setBeginIndex(int beginIndex){ d=D#cs;\
this.beginIndex = beginIndex; >Q_
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} 8*Fn02 p
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/** +2tFX
* @return \-Xtbm
* Returns the currentPage. 3_9CREZCl
*/ FzSL[S4i
publicint getCurrentPage(){
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return currentPage; BK)<~I
} *Ej;}KSv
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/** b)#rUI|O
* @param currentPage |Y6;8e`H
* The currentPage to set. MtF^}/0w!`
*/ =[:E
publicvoid setCurrentPage(int currentPage){ E`xpZ>$mPx
this.currentPage = currentPage; a*}>yad
} qnQ".
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/** 'C`Ykjf
* @return 4*o?2P$Q
* Returns the everyPage. _u;pD-
*/ G$KQgUN~[
publicint getEveryPage(){ hi(e%da
return everyPage; cL%"AVsj
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} >hSu1s:
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/** 0 ;)Q
* @param everyPage - q(a~Ge
* The everyPage to set. Yv)c\hm(7j
*/ m6^#pqSL
publicvoid setEveryPage(int everyPage){ _OJfd
this.everyPage = everyPage; [n&ES\o#(
} 2wPc
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/** G; exH$y
* @return R
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* Returns the hasNextPage. (GGosXU-v
*/ (~bx %
publicboolean getHasNextPage(){ _<F;&(o
return hasNextPage; N^wHO<IO1
} =j~:u.hc'
o%`=+-K
/** ;;
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* @param hasNextPage N(yd<Mw
* The hasNextPage to set. vf#d
*/ Sp?e!`|8
publicvoid setHasNextPage(boolean hasNextPage){ /:{4,aX2
this.hasNextPage = hasNextPage; RL\?i~'KH
} <}'=@a
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/** ;!=i|"PG
* @return -F*vN'
* Returns the hasPrePage. yZm=#.f
*/ f52P1V]
publicboolean getHasPrePage(){ f9},d1k
return hasPrePage; OAiv3"p
} |&
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/** &%@O V:C
* @param hasPrePage G3]#Du
* The hasPrePage to set. 7TI6EKr
*/ Z1v~tqx
publicvoid setHasPrePage(boolean hasPrePage){ b$Dh|-8
this.hasPrePage = hasPrePage; W#^.)V
} KZcmNli&A
r_,;[+!
/** `jr?I {m;
* @return Returns the totalPage. Ya!%o> J%t
* kw#-\RR_c
*/ m__pQu:
publicint getTotalPage(){ l1O"hd'~s
return totalPage; uM,Ps}
} E,K>V:P*
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/** 0b
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* @param totalPage GP %hf{
* The totalPage to set. |#SZdXg
*/ v@M^ukk'}
publicvoid setTotalPage(int totalPage){ /K1cP>oE
this.totalPage = totalPage; ZMiOKVl
} D `V.gV]
u,d5/`E
} UuF(n$B
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]9@
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 E'Ux2sh
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个PageUtil,负责对Page对象进行构造: 5U+4vV/*
java代码: O1t$]k:
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/*Created on 2005-4-14*/ [2Nux0g
package org.flyware.util.page; s/C'f4
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import org.apache.commons.logging.Log; <m1v+cnqo
import org.apache.commons.logging.LogFactory; -MTYtw(
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/** `JPkho
* @author Joa Vq{3:QBR
* $6D*G-*8
*/ NV9JMB{q
publicclass PageUtil { K5XW&|tY!
6'@ {
*
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privatestaticfinal Log logger = LogFactory.getLog x{<l8vL=-c
E!mv}
(PageUtil.class); 'x"(OdM:[
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/** 'U`;4AN
* Use the origin page to create a new page w=rD8@
* @param page u-4@[*^T$
* @param totalRecords vW vu&3tx
* @return DU]KD%kl
*/ qdv O>k3
publicstatic Page createPage(Page page, int H, :]S-T
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totalRecords){ R(VOHFvW6
return createPage(page.getEveryPage(), 2ag8?#
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page.getCurrentPage(), totalRecords); PcU~1m1
} 0('ec60u
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/** /"u37f?[^
* the basic page utils not including exception Rq[d\BN0.d
ykPiZK
handler uh2_Rzln
* @param everyPage 73Jm
* @param currentPage fCJjFL:
* @param totalRecords #+AQ:+
* @return page Q1?*+]
*/ aVc{ aP
publicstatic Page createPage(int everyPage, int 3+h3?
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currentPage, int totalRecords){ |b.xG_-s1
everyPage = getEveryPage(everyPage); (?zD!%
k
currentPage = getCurrentPage(currentPage); <"P-7/j3j
int beginIndex = getBeginIndex(everyPage, hdrsa}{g
\y=oZk4
currentPage); q^EY?;Y
int totalPage = getTotalPage(everyPage, DmLx"%H3
|3@DCbT
totalRecords); 9_O4yTL
boolean hasNextPage = hasNextPage(currentPage, PzNPwd
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totalPage); 15<? [`:6
boolean hasPrePage = hasPrePage(currentPage); Y-YuY
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returnnew Page(hasPrePage, hasNextPage, E8}evi
everyPage, totalPage, K SOD(
currentPage, x6s|al
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beginIndex); $Emu*'
} N~mr@rXC
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privatestaticint getEveryPage(int everyPage){ RLnL9)`W
return everyPage == 0 ? 10 : everyPage; !+^'Ej)z
} Y`bTf@EP>
ZqVbNIY
privatestaticint getCurrentPage(int currentPage){ 'OziP
return currentPage == 0 ? 1 : currentPage; d`B<\Y#{Us
} p T 8?z
x}?<9(nE c
privatestaticint getBeginIndex(int everyPage, int Wx{E\ l
~:bdS 4w
currentPage){ RE%f'y
return(currentPage - 1) * everyPage; KBN% TqH|
} 9T24dofkJ
sEdz`F
privatestaticint getTotalPage(int everyPage, int #H>{>0q
PKSfu++Z
totalRecords){ c8JW]A`9b)
int totalPage = 0; 4Qfsxg
"Nj/{BU
if(totalRecords % everyPage == 0) 4r1\&sI$~
totalPage = totalRecords / everyPage; &o;0%QgF
else x
I.W-js[
totalPage = totalRecords / everyPage + 1 ; 71c[`h*0{
\{lv~I
return totalPage; Zg(Y$ h\
} vCaN [
UGhEaKH~R
privatestaticboolean hasPrePage(int currentPage){ ] [MtG
return currentPage == 1 ? false : true; L#UR>Z#9
} +ZOiL[rS
uD&B{c+a
privatestaticboolean hasNextPage(int currentPage, =W.}&
;J 5z
int totalPage){ x^f)I|t
return currentPage == totalPage || totalPage == #lP8/-s^
ZLv/otf:|"
0 ? false : true; vv @m{,7#Y
} nG!<wlY14P
2Kz+COP+
xZ9:9/Vg
} n_e'n|T
?W'p&(;
3N+lWuE}K
7R2O[=Szq
,94<j,"
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。 zzQWHg]/
Lqj
Qv$
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 fo@^=-4A-
pD732L@q
做法如下: 9RaO[j`
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>[A}-
;[sW\Ou
的信息,和一个结果集List: S }`sp[6
java代码: d qn5G!fI
// o.+?S
LSJ?;Zg(=z
/*Created on 2005-6-13*/ d]l8ei@>h
package com.adt.bo; e{P v:jl
_6ZjF>f
import java.util.List; LmF ,en5
\beO5]KS<
import org.flyware.util.page.Page; C8}:z\A_@Z
!LI<%P)
/** ~9dpB>+
* @author Joa L8QWEFB|
*/ .gRj^pu
publicclass Result {
B )r-,M
A IP~A]T
private Page page; az(<<2=
PLyity-L[7
private List content; \n)',4mY
Zh<;r;2
/** )|F|\6:ne
* The default constructor iEr,ly
*/ []>'Dw_r
public Result(){ kz"uTJK
super(); #&&T1;z"#
} _>;Wz7
!Lf<hS^
/** L[G O6l
* The constructor using fields ??rS h Mu
* 0mY Y:?v
* @param page 5</$dcG
* @param content Wy}I"q[~So
*/ @w[i%F,&`
public Result(Page page, List content){ iq(PC3e`V
this.page = page; 'pdTV:]zA
this.content = content; XIHN6aQ{X
} |p11Jt[
-Aj)<KNx[
/** (\9`$
* @return Returns the content. V#t_gS
*/ X
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publicList getContent(){ Kx__&a
return content; j i"g)d6
} Bh>L"'.2
d8j1L/e
/** P#,u9EIJ
* @return Returns the page. QHEtG2
*/ kmI0V[Y
public Page getPage(){ T~TP
return page; yB*,)x0
@
} FK|O^->B
<uH8Fivb
/** `FP?9R6Y
* @param content WNjwv/
* The content to set. kN1MPd4Yh
*/ kSQ8kU_w+
public void setContent(List content){ ':'g!b`/
this.content = content; n_8[bkbi
} E$e7(D
~4S$+*'8
/** rz?Cn
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* @param page *Gbhk8}V'
* The page to set. RpHlq
*/ }'X=&3m
publicvoid setPage(Page page){ hvd}l8
this.page = page; Y::0v@&(
} lfGyK4:
} ]n22+]D
_"DS?`z6
4`IM[DIG~
w2)Ro:G
ou|emAV
2. 编写业务逻辑接口,并实现它(UserManager, DX>a0-Xj
W?
iA P
UserManagerImpl) Qw5nfg3T
java代码: Wgq|Q*
XH:*J+$O
z*y!Ml1
/*Created on 2005-7-15*/ NWBYpGZx
package com.adt.service; GXNf@&
[|u^:&az
import net.sf.hibernate.HibernateException; S;Bk/\2
y}Ky<%A!P
import org.flyware.util.page.Page; n\#YGL<n
29R-Up!SVN
import com.adt.bo.Result; AKNx~!%2
v\0 G`&^1
/** Q=\
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* @author Joa LSo!_tY
*/ 8!g
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publicinterface UserManager { S)rZE*~2
Nd_fjB
public Result listUser(Page page)throws bQAznd0
KaGUpHw
HibernateException; &c`-/8c
15$xa_w}L
} ;|N:FG
^?69|,
)M*w\'M
%B3~t>
[}X|&`'i
java代码: ?mQ^"9^XS
GN.Oa$
|Lq8cA)|y
/*Created on 2005-7-15*/ o<2GtF1"o
package com.adt.service.impl; _`$LdqgE
)vr@:PE
import java.util.List; j)1y v.
@u3`lhUcT
import net.sf.hibernate.HibernateException; ^6 6!f 5^W
H^_,e= j
import org.flyware.util.page.Page; N!A20Bv
import org.flyware.util.page.PageUtil; y!e]bvN
}fpya2Xt
import com.adt.bo.Result; fGgt[f[
import com.adt.dao.UserDAO; #%"q0"
import com.adt.exception.ObjectNotFoundException; 4 p_C+4
import com.adt.service.UserManager; &[.5@sv
(iIw}f)w
/** X@nBj;
* @author Joa fSh5u/F!
*/ T?9D?u?]
publicclass UserManagerImpl implements UserManager { *P()&}JK
NOz3_k
private UserDAO userDAO; ?@V R%z
fS]&?$q
/** :dmE/Tq
* @param userDAO The userDAO to set. yI w}n67
*/ ^}3^|jF
publicvoid setUserDAO(UserDAO userDAO){ <QtZ6-;_f
this.userDAO = userDAO;
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} fJ,N.O+9E
8$Q`wRt(%
/* (non-Javadoc) l=^A41L_
* @see com.adt.service.UserManager#listUser -"(*'hD
r^9l/H~$
(org.flyware.util.page.Page) 4.6$m
*/ f*ZU a
public Result listUser(Page page)throws Z1Qz
LvWs
l,wlxh$}(
HibernateException, ObjectNotFoundException { tz1@s nes
int totalRecords = userDAO.getUserCount(); \lL[08G
if(totalRecords == 0) !+xQ
throw new ObjectNotFoundException ?}||?2=P
SNEhP5!
("userNotExist"); c0Ug5Vr
page = PageUtil.createPage(page, totalRecords); gW,[X(
List users = userDAO.getUserByPage(page); a+h$u
returnnew Result(page, users); <+8'H:wz
} 0V%c%]PH
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} *7Dba5B
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tMr7d
&|SWy
2N
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {+N<
9(O
Z:b?^u4.
询,接下来编写UserDAO的代码: EZtU6kW"
3. UserDAO 和 UserDAOImpl: Xj?Wvt
java代码: QxT'\7f
~C-Sr@ a?/
IQQv+af5
/*Created on 2005-7-15*/ :XKYfc_y
package com.adt.dao; ~G@NWF?7
[%IOB/{N
import java.util.List; Da^q9,|
+ a#&W}K
import org.flyware.util.page.Page; ;i{B,!#
,CE/o7.FG
import net.sf.hibernate.HibernateException; x"r0<RK
u ExLj6
/** T+8Yd(:hX
* @author Joa ,n|si#
*/ <y 4(!z"
publicinterface UserDAO extends BaseDAO { `RTxc
@uSO~.7
publicList getUserByName(String name)throws -oD,F
$Rb
Bz+oMN#XJ
HibernateException; +sNS
+/OSg.
publicint getUserCount()throws HibernateException; whI{?NP
.j6udiv5
publicList getUserByPage(Page page)throws 2j\_svw'
[V}vd@*k
HibernateException; +)jUA]hJ/
F)P:lvp<r
} QE]@xLz
l;F"m+B!$
ZvY"yl?e
,%i
Scr,z
T2{e1 =Z7
java代码: V:0IBbh)w
0
_!0\d#c
7KtU\u
/*Created on 2005-7-15*/ gt4GN`-k
package com.adt.dao.impl; ]aN9mT
N
,@"yr>Q9#6
import java.util.List; *i#2>=)
Zy0M\-Mn
import org.flyware.util.page.Page; VPN
9 Ql=
z zG=!JR
import net.sf.hibernate.HibernateException; ;R$G.5h
import net.sf.hibernate.Query; A#>wbHjWF
5-dt0I@<
import com.adt.dao.UserDAO; g&RpE41x
"2e3 <:$
/** l;$F[/3a
* @author Joa "$BkO[IS
*/ 3
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public class UserDAOImpl extends BaseDAOHibernateImpl UrniJB]
g%2G=gR$?z
implements UserDAO { ra^</o/
2BY|Cp4R
/* (non-Javadoc) b"g^Jm! j
* @see com.adt.dao.UserDAO#getUserByName G<Z}G8FW^
3Vu}D(PJ
(java.lang.String) ];.5*a%*
*/ 3 s\UU2yr
publicList getUserByName(String name)throws ]0i[=
L03I:IJ
HibernateException {
K^{j$
String querySentence = "FROM user in class b:1B
>
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com.adt.po.User WHERE user.name=:name"; kH g|!
Query query = getSession().createQuery H4Bt.5O*
&-/J~b)"
(querySentence); TtJX(N~
query.setParameter("name", name); He_O+[sc
return query.list(); H UJqB0D
?
} ~B<\#oO
eDd&vf
/* (non-Javadoc) #y\O+\4e
* @see com.adt.dao.UserDAO#getUserCount() ,Wtw0)4
*/ }$?FR
publicint getUserCount()throws HibernateException { Uo3
int count = 0; DVQr7tQf
String querySentence = "SELECT count(*) FROM qw+7.h#V
YB*)&@yx
user in class com.adt.po.User"; 5{H)r
Query query = getSession().createQuery GtRpgM
+:A `e+\
(querySentence); 6Dd>ex!-A
count = ((Integer)query.iterate().next <XL%*
6 `6I<OJ\
()).intValue(); pbzt8 P[
return count; ;5X6`GlS#5
} +;,{`*W+N
'[
c-$X2Ak
/* (non-Javadoc) WO>A55Xya
* @see com.adt.dao.UserDAO#getUserByPage RqROl!6
l6zAMyau5
(org.flyware.util.page.Page) EXdX%T\
*/ ^%oH LsY9
publicList getUserByPage(Page page)throws h(WlJCln
/OKp(u;)z
HibernateException { VnuG^)S
String querySentence = "FROM user in class %+r(*Q+0$f
^;II@n
i
com.adt.po.User"; hC-uz _/3
Query query = getSession().createQuery hu-]SGb6
|E13W
(querySentence); k(f),_
query.setFirstResult(page.getBeginIndex()) 1P]J3o
.setMaxResults(page.getEveryPage()); HSud$(w
return query.list(); Eu|/pH=:
} fMwF|;
qJ" (:~
} s.(.OXD&
y9}qB:[bR
f y|JE9Io_
4n#u?)
H
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至此,一个完整的分页程序完成。前台的只需要调用 m.P
F'_)/
]n=z(2Z9lD
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?`TQ!m6y
o.$48h(
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~U+<JC Z
h`Jc%6o
webwork,甚至可以直接在配置文件中指定。 QXI~Toddj
#h.N#{9
下面给出一个webwork调用示例: Eq@sU?j
java代码: R14&V1 tZ
gvVy0nJI~
Gn7\4,C
/*Created on 2005-6-17*/ iBWzxPv:z
package com.adt.action.user; LBio$67F
nANl9;G
import java.util.List; H:b"Vd"x9
M_O$]^I3w
import org.apache.commons.logging.Log; 3SM'vV0[
import org.apache.commons.logging.LogFactory; A._CCou
import org.flyware.util.page.Page; . (&6gB
+R?E @S
import com.adt.bo.Result; Gb2|e.z
import com.adt.service.UserService; v~RxtTu
import com.opensymphony.xwork.Action; u!xgLf'`
4][VK/v+
/** DN9x<%/-
* @author Joa !/`AM<`o
*/ !yg &zzP*
publicclass ListUser implementsAction{ =ZHN]PP
eDo4>k"5
privatestaticfinal Log logger = LogFactory.getLog QVn2`hr
}P=FMme{F(
(ListUser.class); -/3h&g
TrZ!E`~
private UserService userService; kW+>"3
=Q"thsR
private Page page; Zy Df@(z`
DmoY],9I+p
privateList users; VK9E{~0=
[/ CB1//Y
/* !d0$cF):
* (non-Javadoc) ~#EXb?#uS
* @"cnPLh&
* @see com.opensymphony.xwork.Action#execute() Pf8_6 z_
*/ [:,|g;=Y}
publicString execute()throwsException{ uUl ;}W
Result result = userService.listUser(page); C&q}&=3r
page = result.getPage(); R||$Wi[$
users = result.getContent(); [L7S`Z
return SUCCESS; Ev#,}l+
} 2!f'l'}
bil>;&h
/** 7ey|~u2
* @return Returns the page. ( 3,7
*/ 57 Vn-
public Page getPage(){ 9U9ghWH8
return page; .&=\
*cZc
} AB!({EIi
T5@t_D>8
/** w6 Y+Y;,'f
* @return Returns the users. P^-x
*/ Ty 6 XU!
publicList getUsers(){ aF=;v*
return users; nP=/XiCj
} a$"Z\F:x
4/o9K*M+
/** 54JI/!a
* @param page p<VW;1bt5
* The page to set. 4J[bh
*/ v&^N +>p
publicvoid setPage(Page page){ RplcM%YJn
this.page = page; kSJ:4! lFU
} k \t6b1.M
d76C]R5L
/** */]1?M@P)
* @param users LQ$dT#z2A
* The users to set. aBF<it>
*/ OOsd*nX/
publicvoid setUsers(List users){ 3e[k 9`
this.users = users; [xs`Pi
} jaTCRn3|<
7")&njQ/x
/** ^-}3+YA
* @param userService lZ+1A0e
* The userService to set. .b%mr:nEt7
*/ F fzY3r+
publicvoid setUserService(UserService userService){ ^w
RD|
this.userService = userService; P.|g4EdND
} ~fA H6FdZ\
} zpcm`z
lVb;,C%K
]o8~b-
V[|k:($
-}JRsQ+rgM
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, atFu
KYI
FLlL0Gu
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 I8hmn@ce
*u<@_Oa
么只需要: "jl`FAu)q
java代码: 3TD!3p8
l5k]voG
8j%lM/ v
<?xml version="1.0"?> 2wh{[Q2f
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 5a l44[
Ks7kaX
1.0//EN" "http://www.opensymphony.com/xwork/xwork- hWu#}iN
?@_,_gTQ
1.0.dtd"> s&OwVQ<M
rNHV
<xwork> |z%*}DPrpa
w<4){.dA
<package name="user" extends="webwork- A7:W0Gg
]| =#FFz
interceptors"> v3jx2Z
UUql"$q
<!-- The default interceptor stack name yIThzyS
(au7wI{
--> <Gu dx>I
<default-interceptor-ref lO|H:7
Q ?W6
name="myDefaultWebStack"/> &-Zg0T&tZ
DU4Prjb'
<action name="listUser" T1b9Zqc)f
=mk7'A>l
class="com.adt.action.user.ListUser"> 3?(||h{
<param `S7${0e
?+#E&F
name="page.everyPage">10</param> ?3i-wpzMp
<result IF*kLl?
{GH
0
J"
name="success">/user/user_list.jsp</result> 1z(y>`ZBq
</action> dQFx]p3L
$}7WJz:
</package> KH&xu,I
2?7a\s
</xwork> C44Dz.rs
l>9ZAI\^
m;LeaD}0
HPj7i;?O
f&>Q6 {*]
B6Tn8@O
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 (iiyptJ
tL4xHa6v]
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 'x10\Q65[
\bb,gRfP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !$+J7\&7p
dDk<J;~jGJ
Lp/]iZ@
7QRtNYo#\
{ByT,92
我写的一个用于分页的类,用了泛型了,hoho VL<)d-
IV:Knh+
?
java代码: ji2if.t@
G>{;@u
FyQ^@@
package com.intokr.util; )P.|Xk:r
B|~\m~
import java.util.List; D`.CXFI+U
Efw/bTEg
/** |xaA3UA
* 用于分页的类<br> ZD0Q<8%
* 可以用于传递查询的结果也可以用于传送查询的参数<br> fD|ox
* zUxF"g-W
* @version 0.01 413r3/
* @author cheng >[Q(!Ai
*/ femAVx}go
public class Paginator<E> { bLoYg^T/
privateint count = 0; // 总记录数 sM~|}|p
privateint p = 1; // 页编号 FUm-Fp
privateint num = 20; // 每页的记录数 )f'cy@b
privateList<E> results = null; // 结果 i@_|18F]`
M ~!*PCd5
/** (F7!&] 8%
* 结果总数 J74nAC%J^
*/ crC];LMl/
publicint getCount(){ 4Kt?; y
;
return count; '89D62\89
} Hj;j\R >2
w>rglm&
publicvoid setCount(int count){ f.'o4HSj
this.count = count; ./ib{ @A.
} f5/ba9nI
q@u$I'`Bs
/** h_d!G+-]
* 本结果所在的页码,从1开始 qx53,^2
* Z!|nc.
* @return Returns the pageNo. /)y~%0
*/ /{1 xpR
publicint getP(){ mrd(\&EhA
return p; 4k$BqM1
} JUU0Tx:`9)
)CXJRo`j0
/** |g4!Yd
* if(p<=0) p=1 c#`Z[
* S3j/(BG
* @param p M* QqiE
*/ kAbT&Rm"
publicvoid setP(int p){ FAU^(]-5m
if(p <= 0) ;Z.}~d6>!
p = 1; F+L q
this.p = p; g >-iBxml
} |vWx[=`o
.Fh5:WN
/** ;][1_
* 每页记录数量
[?Aq#av
*/ ~Cj+6CrT
publicint getNum(){ '1r:z, o|
return num; xb_35'$M
} s bW`
^O[qCX
/** <h7C_^L10\
* if(num<1) num=1 lcIX
l&