Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !D!Q]M5oU
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K]1A,Q
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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 ?Bno?\
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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 i]JD::P_H
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分页支持类: .i)
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java代码: g ]e^;
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package com.javaeye.common.util; 5hF
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import java.util.List; C4Z}WBS(
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publicclass PaginationSupport { -W38#_y/\
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publicfinalstaticint PAGESIZE = 30; @GNNi?EY
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privateint pageSize = PAGESIZE; 0JN>w^
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privateList items; 1qp<Fz[
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privateint totalCount; d}2tqPy a
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privateint[] indexes = newint[0]; ^K.
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privateint startIndex = 0; M=:!d$c
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public PaginationSupport(List items, int gG*]|>M JI
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totalCount){ j}t"M|`
setPageSize(PAGESIZE); AqnDsr!
setTotalCount(totalCount); /
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setItems(items); k<(G)7'gm
setStartIndex(0); T5H[~b|9-
} 5tfD*j n
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public PaginationSupport(List items, int s&&8~
)H
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totalCount, int startIndex){ q$RJ3{Sf
setPageSize(PAGESIZE); ?&A)%6` ~
setTotalCount(totalCount); O=m_P}K
setItems(items); 7~&
setStartIndex(startIndex); mUSrC U_}
} uy'm2
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public PaginationSupport(List items, int #@%DY*w]v
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totalCount, int pageSize, int startIndex){ 11Sflj
setPageSize(pageSize); >1uo5,wrF
setTotalCount(totalCount); }9=X*'BO
setItems(items); 3kqO5+,C
setStartIndex(startIndex); "}ibH{$lM
} X%JQ_Z
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publicList getItems(){ tV.qdy/]}
return items; LL% Aw)Q`
} p6S{OUiG
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publicvoid setItems(List items){ [u*-~(
this.items = items; H#/ #yVw
} 8`g@
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publicint getPageSize(){ ={~?O&Jh
return pageSize; z3-A2#c
} }Br=eaY
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publicvoid setPageSize(int pageSize){ )T0%<(J
this.pageSize = pageSize; +;#z"m]
} XS#Jy
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publicint getTotalCount(){ R;d)I^@
return totalCount; 4C:-1gu7
} [pY1\$,
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publicvoid setTotalCount(int totalCount){ /FJ.W<hw
if(totalCount > 0){ 6&9}M Oc
this.totalCount = totalCount; 1 sJtkge:
int count = totalCount / o,NTIh
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pageSize; QH>e_
if(totalCount % pageSize > 0) U~CG(9
count++; +jD*Jtb<
indexes = newint[count]; n3z]&J5fr
for(int i = 0; i < count; i++){ ;15j\{r
indexes = pageSize * pZxuV(QP`
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i; Nh^
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} &0`[R*S
}else{ 1
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this.totalCount = 0; h/goV
} fvE:'( #?
} r+RFDg/
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publicint[] getIndexes(){ BT *z^ZH
return indexes; 6lAHB*`
} cM?i _m
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publicvoid setIndexes(int[] indexes){ ?+P D?c7
this.indexes = indexes; N\{{:<Cp\
} UG !+&ii|
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publicint getStartIndex(){ GbB:K2
return startIndex; kVRh/<s
} b[/uSwvi
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publicvoid setStartIndex(int startIndex){ x=I|O;"><
if(totalCount <= 0) `b:yW.#w3l
this.startIndex = 0; huat,zLS
elseif(startIndex >= totalCount) WU+OS(
this.startIndex = indexes aj`_*T"A
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[indexes.length - 1]; =O
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elseif(startIndex < 0) .,*68S0k7
this.startIndex = 0; DG-XX.:z
else{ dX;Q\
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this.startIndex = indexes *Dhy a g
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[startIndex / pageSize]; zL@FN sYVM
} "6t#
}
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publicint getNextIndex(){ [/Vi*Z
int nextIndex = getStartIndex() + "8l&m6`U-
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pageSize; MJ_]N+
if(nextIndex >= totalCount) |*5HNP
return getStartIndex(); U9t-(`[j?
else [XbNZ6
return nextIndex; o,gH*
} <$@*'i^7Ez
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publicint getPreviousIndex(){ ?,z/+/:
int previousIndex = getStartIndex() - o>jM4sk$
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pageSize; _%gu<Ys
if(previousIndex < 0) u`
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return0; `Kb"`}`_vm
else PBOZ^%k
return previousIndex; U-ADdOh"q
} TfnBPO
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} "n%0L4J
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抽象业务类 |w+N(wcJ
java代码: "pMx(
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/** [Ol~}@gV
* Created on 2005-7-12 'Da*MGu9
*/ ;hb_jW-0W
package com.javaeye.common.business; 3R&
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import java.io.Serializable; -$sVqR>_
import java.util.List; ZwOX ,D
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import org.hibernate.Criteria; @/W~lJ!e
import org.hibernate.HibernateException; ;!(GwgllD
import org.hibernate.Session; @8eQ|.q]Q
import org.hibernate.criterion.DetachedCriteria; #p7K2
import org.hibernate.criterion.Projections; 8)bqN$*h
import ]114\JE
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org.springframework.orm.hibernate3.HibernateCallback; LTw.w:"J
import %$[#/H7=W
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org.springframework.orm.hibernate3.support.HibernateDaoS 5>\~jf
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upport; A-f,&TO
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import com.javaeye.common.util.PaginationSupport; l4$Iv:
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public abstract class AbstractManager extends !:wA\mAd
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HibernateDaoSupport { 7m4*dBTr
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privateboolean cacheQueries = false; p(6KJK\
e+<'=_x {
privateString queryCacheRegion; "'74GY8,
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publicvoid setCacheQueries(boolean 3|(<]@
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cacheQueries){ N?2C*|%f
this.cacheQueries = cacheQueries; `8/D$
} p(!d,YSE
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publicvoid setQueryCacheRegion(String F%IvgXt5
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queryCacheRegion){ Hu$y8_Udw
this.queryCacheRegion = $X,dQ]M
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queryCacheRegion; .'PS L
} 4 '5|YGQj
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publicvoid save(finalObject entity){ fS$;~@p
getHibernateTemplate().save(entity); [`kk<$=,&
} $38)_{
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publicvoid persist(finalObject entity){ N6HeZB":
getHibernateTemplate().save(entity); ~P BJ~j+G
} 89x;~D1
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publicvoid update(finalObject entity){ m/3,;P.6
getHibernateTemplate().update(entity); *x:*Q \|
} NfWL3"&X
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publicvoid delete(finalObject entity){ ;0lY_ii
getHibernateTemplate().delete(entity); 20# V?hX3
} WbwwI)1
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publicObject load(finalClass entity, =Z ql6D
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finalSerializable id){ zpjE_|
return getHibernateTemplate().load ~jzjJ&O&
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(entity, id); 8S7#tb@3
} ^J;rW3#N8
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publicObject get(finalClass entity, 6Yl+IP];i
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finalSerializable id){ adPd}rt;
return getHibernateTemplate().get S_TD o
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(entity, id); |nfMoUI
} ~1{ppc+
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publicList findAll(finalClass entity){ ;W]9DBAB
return getHibernateTemplate().find("from j^%N:BQ&
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" + entity.getName()); g^^pPVK_
} %>$Puy\U
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publicList findByNamedQuery(finalString d^f rKPB
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namedQuery){ ac\( [F-
return getHibernateTemplate 0*_E'0L8e
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().findByNamedQuery(namedQuery); jtUqrJFlQ
} Qj'Ik`o
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publicList findByNamedQuery(finalString query, )xiu
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finalObject parameter){ \VA*3U^@
return getHibernateTemplate
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().findByNamedQuery(query, parameter); w {"1V7|
} (k8}9[3G
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publicList findByNamedQuery(finalString query, a{@}vZx>3
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finalObject[] parameters){ ]x{.qTtw
return getHibernateTemplate U
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().findByNamedQuery(query, parameters); QZtQogNy#
} ~d].<Be
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publicList find(finalString query){ #f<v%
return getHibernateTemplate().find NSBcYObX
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(query); Sg4{IU
} b\"w/'XX
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publicList find(finalString query, finalObject b+|3nc!
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parameter){ kY @(-
return getHibernateTemplate().find U2l3E*O
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(query, parameter); 0y6M;"&~E
} DzQ
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public PaginationSupport findPageByCriteria ]8}51y8
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(final DetachedCriteria detachedCriteria){ 0 ZM(heQ
return findPageByCriteria E5$]0#jB
.] sJl
(detachedCriteria, PaginationSupport.PAGESIZE, 0); wapSpSt
} "4;nnq
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public PaginationSupport findPageByCriteria YZj*F-}
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(final DetachedCriteria detachedCriteria, finalint 0/b
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startIndex){ IHYLM;@L
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, xH xTL>,?
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startIndex); +.Ij%S[Px5
} Zym6btc
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public PaginationSupport findPageByCriteria ;Mup@)!j
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(final DetachedCriteria detachedCriteria, finalint u0c}[BAF
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pageSize, B*,)@h
finalint startIndex){ \gk.[={^P
return(PaginationSupport) ;~EQS.Qp
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getHibernateTemplate().execute(new HibernateCallback(){ DK\XC%~m
publicObject doInHibernate ?9kC[4G
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(Session session)throws HibernateException { ?B1Zfu0
Criteria criteria = pA~}_
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detachedCriteria.getExecutableCriteria(session); p 1'l D
int totalCount = I I+y
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((Integer) criteria.setProjection(Projections.rowCount y
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()).uniqueResult()).intValue(); =FrB{Eu
criteria.setProjection 3R3H+W0{
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(null); Zd6ik&S
List items = )1uiY
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criteria.setFirstResult(startIndex).setMaxResults 5e/YEDP
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(pageSize).list(); n^Ca?|}
,
PaginationSupport ps = }l|S]m!
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new PaginationSupport(items, totalCount, pageSize, LE\=Y;%
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startIndex); UqOBr2UmG
return ps; u^~7[OkE
} RpQeQM=
}, true); #i[:oC6m:
} r3l1I}
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public List findAllByCriteria(final mG jB{Q+
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DetachedCriteria detachedCriteria){ 2'DCB{Jv
return(List) getHibernateTemplate @-
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().execute(new HibernateCallback(){ #ES[),+|mB
publicObject doInHibernate An{>39{
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(Session session)throws HibernateException { {^WK#$]
Criteria criteria = tk&AZb,sP
;
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detachedCriteria.getExecutableCriteria(session); 2R[v*i^S
return criteria.list(); {]k#=a4
} xB
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}, true); BNfj0e 5b
} m,k0 h%
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public int getCountByCriteria(final Mg;pNK\n
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DetachedCriteria detachedCriteria){ U.e!:f4{
Integer count = (Integer) P`biHs8O
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getHibernateTemplate().execute(new HibernateCallback(){ x+X@&S
publicObject doInHibernate ';tlV
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(Session session)throws HibernateException { A2|Bbqd
Criteria criteria = @dWA1tM
* Gg7(cnpw
detachedCriteria.getExecutableCriteria(session); Lce,]z\_
return }r:"X<`
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criteria.setProjection(Projections.rowCount 6g|,]{
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()).uniqueResult(); @t%da^-HS"
} >C0B!MT?3%
}, true); _3`GZeGV
return count.intValue(); 4uXGpsL
} X+4Uh
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} kR<sSLEb
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用户在web层构造查询条件detachedCriteria,和可选的 |! 9~
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 E`)e
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PaginationSupport的实例ps。 REh"/d
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ps.getItems()得到已分页好的结果集 /TMVPnvz.
ps.getIndexes()得到分页索引的数组 >ywl()4O
ps.getTotalCount()得到总结果数 56pj(}eq
ps.getStartIndex()当前分页索引 Y=XDN:
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 -'&l!23a~
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 H:G``Vq;0m
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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 &* VhtT?=5
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一下代码重构了。 5RT#H0/+
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我把原本我的做法也提供出来供大家讨论吧: !XTzsN
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首先,为了实现分页查询,我封装了一个Page类: _{o 3 y"DZ
java代码: (Aw@}!
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/*Created on 2005-4-14*/ C^$E#|E9 N
package org.flyware.util.page; YIN* '!N
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/** )a^&7
* @author Joa 4zs0+d+
* pW[TufTa
*/ %s}{5Qcl/
publicclass Page { nKE^km
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/** imply if the page has previous page */ (\qf>l+*
privateboolean hasPrePage; 7^>~k}H
>:.c?{%g*
/** imply if the page has next page */ DlzL(p@r
privateboolean hasNextPage; Q%6zr9
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/** the number of every page */ -']Idn6
privateint everyPage; PVi;h%>Y
dsX"S;`v
/** the total page number */ z^wod
privateint totalPage; O}C*weU
@Ov}X]ELi
/** the number of current page */ c6b51)sQ"
privateint currentPage; c6jVx_tt.
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/** the begin index of the records by the current `{ Ox=+]M
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query */ uBG!R#T
privateint beginIndex; [#!Y7Ede
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/** The default constructor */ wtbN@g0
public Page(){ yFm88
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} "uplk8iCJ
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/** construct the page by everyPage -I4@6vE,
* @param everyPage /QB;0PrE
* */ _k}Qe;
public Page(int everyPage){ _rSwQ<38>
this.everyPage = everyPage; (0@b4}Z
} W2`3PEa
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/** The whole constructor */ n3?
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public Page(boolean hasPrePage, boolean hasNextPage, BW)@.!C
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int everyPage, int totalPage, mY=sh{ir
int currentPage, int beginIndex){ Xtz29
this.hasPrePage = hasPrePage; bR}fj.gP
this.hasNextPage = hasNextPage; 07=I&Pum
this.everyPage = everyPage; pcIS}+L
this.totalPage = totalPage; I\Y N!
this.currentPage = currentPage; ]*MVC/R,
this.beginIndex = beginIndex; Pc?"H!Hkn
} #t2N=3dOj
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/** "C3J[) qC
* @return
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* Returns the beginIndex. 2WLLI8
*/ |oOAy
publicint getBeginIndex(){ P(-
return beginIndex; tYgHJ~1L*
} k&L/JzzI
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/** +tt!xfy
* @param beginIndex -cJ,rrN_9
* The beginIndex to set. "Uf1;;b
*/ com4@NK
publicvoid setBeginIndex(int beginIndex){ FzSL[S4i
this.beginIndex = beginIndex; <H#0pFB
} *Ej;}KSv
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/** -Ju;i<
* @return [zq2h3r
* Returns the currentPage. Xk'Pc0@a
*/ `<P:ly.
publicint getCurrentPage(){ }(DH_0
return currentPage; SXe1Q8;
} i`<L#6RBT
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/** 2~QJ]qo =
* @param currentPage 3.P7GbN
* The currentPage to set. j( k%w
*/ B#`'h~(7
publicvoid setCurrentPage(int currentPage){ - q(a~Ge
this.currentPage = currentPage; 6WIs*$T2*
} Gj%q:[r
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/** X!ldL|Ua%
* @return b>i5r$S8G
* Returns the everyPage. Tb;,t=;u
*/ SHB'g){P
publicint getEveryPage(){ hbr3.<o1lY
return everyPage; FG!hb?_1
} Zv@
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/** 'Q7^bF^
* @param everyPage 8lDb<i
* The everyPage to set. Z'uiU e`&
*/ rH,@"(p\
publicvoid setEveryPage(int everyPage){ 4^YE*6z
this.everyPage = everyPage; PJ?C[+&
} K0B<9Wi|
p_]b=3wt~
/** ?*xH
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* @return Dm}M8`|X
* Returns the hasNextPage. @^ti*`
*/ /d!
publicboolean getHasNextPage(){ fE)o-q6Z
return hasNextPage; ]91QZ~4a
} C4gES"T
imzPVGCD{
/** -&]!ig5v
* @param hasNextPage !J!&JQ|
* The hasNextPage to set. %\|{_]h}y
*/ .m\0<8C
publicvoid setHasNextPage(boolean hasNextPage){ KZ#\ >
this.hasNextPage = hasNextPage; E8R;S}PA
} ;PMh>ZE`
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/** S3WUccv
* @return q
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* Returns the hasPrePage. IoK/ 2Gp
*/ gX-hYQrC
publicboolean getHasPrePage(){ KUm?gFh
return hasPrePage; goF87^M
} 34N~<-9AY
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/** 53a^9
* @param hasPrePage
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* The hasPrePage to set. liLhvcd
*/ y5O &9Ckw
publicvoid setHasPrePage(boolean hasPrePage){ ,=[%#gS
this.hasPrePage = hasPrePage; fn5-Tnsq*
} %.$7-+:7A
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/** k 9z9{
* @return Returns the totalPage. "8cI]~V
* v*dw'i
*/ to,\n"$~!
publicint getTotalPage(){ pz)>y&_o
return totalPage; &(32s! qH
} |KS,k|).
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/** vDi Opd
* @param totalPage ^->S7[N?
* The totalPage to set. %8xRT@Q
*/ woPj>M
publicvoid setTotalPage(int totalPage){ 3/Z>W|w#w
this.totalPage = totalPage; k1zK3I&c_
} 02*qf:kTnA
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} $of2 lA
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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 9`Fw}yAt
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个PageUtil,负责对Page对象进行构造: 8 p[n>qV9
java代码: i-5,*0e6m
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/*Created on 2005-4-14*/ hEsiAbTyF
package org.flyware.util.page; cY_ke
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import org.apache.commons.logging.Log; 0NC70+4L
import org.apache.commons.logging.LogFactory; T>L?\-
3+h3?
/** $$&.}}.,
* @author Joa +s"6[\H1d
* >,]8iMh
*/ hdrsa}{g
publicclass PageUtil { }58MDpOF1
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privatestaticfinal Log logger = LogFactory.getLog qa
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9_O4yTL
(PageUtil.class); xSK#ovH2
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/** tB,(12@W
* Use the origin page to create a new page )(-;H|]?
* @param page F!0iM)1o
* @param totalRecords K SOD(
* @return }F _c0zM
*/ ~qGW94
publicstatic Page createPage(Page page, int 'D
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totalRecords){ f6`GU$H
return createPage(page.getEveryPage(), C=r2fc~w
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page.getCurrentPage(), totalRecords); I_u/
} Y6sX|~Zy
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/** `;;l {8
* the basic page utils not including exception p.=9[`
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handler yivu|q
* @param everyPage &EQhk9j
* @param currentPage Rxd4{L
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* @param totalRecords bP9ly9FH
* @return page {a:05Y
*/ =ZIT!B?4
publicstatic Page createPage(int everyPage, int #[lhem] IC
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currentPage, int totalRecords){ 3 J04 $cD
everyPage = getEveryPage(everyPage); `<X-3)>;G
currentPage = getCurrentPage(currentPage); 8aP/vToa
int beginIndex = getBeginIndex(everyPage, "/i$_vl
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currentPage); CPP~,E_
int totalPage = getTotalPage(everyPage, SE]5cJ'>
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totalRecords); =W.}&
boolean hasNextPage = hasNextPage(currentPage, $El-pMq
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totalPage); UPfO;Z`hJ
boolean hasPrePage = hasPrePage(currentPage); V;XKvH
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returnnew Page(hasPrePage, hasNextPage, <s'de$[
everyPage, totalPage, P#~B@d
currentPage, p?rlx#M
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beginIndex); m,E$KHt (
} p%"dYH%]&0
fo@^=-4A-
privatestaticint getEveryPage(int everyPage){ uPA
(1
return everyPage == 0 ? 10 : everyPage; G:1'}RC :
} y~
=H`PAE
d qn5G!fI
privatestaticint getCurrentPage(int currentPage){ Bvn3:+(47
return currentPage == 0 ? 1 : currentPage; $>XeC}"x68
} tF0jH+7J-
-Ks>s
privatestaticint getBeginIndex(int everyPage, int my.EvN
]yU"J:/
currentPage){ H,!xTy"Wh
return(currentPage - 1) * everyPage; :jLL IqhB
} NXY jb(4:
' [
4;QYw
privatestaticint getTotalPage(int everyPage, int DYD<?._I
@LKQ-<dZG
totalRecords){ yLX $SR
int totalPage = 0; 2@D`^]]
9B: 3Ha=
if(totalRecords % everyPage == 0) +T+@g8S
totalPage = totalRecords / everyPage; |@Tga_0p
else T
pkSY`T
totalPage = totalRecords / everyPage + 1 ; rVYoxXv
afEa@et'
return totalPage; x%G3L\5
} B[t^u\Fk
|7s2xRc
privatestaticboolean hasPrePage(int currentPage){ &v{Ehkr*
return currentPage == 1 ? false : true; 5</$dcG
} SiratkP9n7
yw3"jdcl
privatestaticboolean hasNextPage(int currentPage, yGZsNd {a&
@X2*O9
int totalPage){ p
T(M>LP83
return currentPage == totalPage || totalPage == :gh[BeqQ)
e3?=1ZB
0 ? false : true; X
W)TI
} X*8y"~X|vq
0s#72}n
c3A\~tHW
} J-F".6i5
E7fx4kV
J!6FlcsZm
Aw o)a8e
;;Q^/rkC
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。 {4 Of.
z ^gJy,T
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 Ifj&S'():
6OES'3 Cy
做法如下: Ccf/hA#mb
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (q>
TKM
tZrc4$D-
的信息,和一个结果集List: ^QB[;g.O
java代码: *Gbhk8}V'
-Mt
5< s
C_.9qo]DT7
/*Created on 2005-6-13*/ g,ZA\R~
package com.adt.bo; ie}OZM
u2V-V#jS
import java.util.List; mP(3[a_Q
<qCa9@Ea
import org.flyware.util.page.Page; mo0\t#jA
(B7G'h.?
/** 0J)s2&H
* @author Joa Ac7^JXh%
*/ ]rmBM
publicclass Result { 1gEH~Jmj
S2~cAhR|M
private Page page; "n-'?W!
[M_{~1xX
private List content; PxHFH pL
vh9* >[i
/** AKNx~!%2
* The default constructor bf3!|Um
*/ gt&|T
j
public Result(){ ,b+NhxdZ
super(); VSj!Gm0LB
} kmuksT\)a
15$xa_w}L
/** (}"D x3K
* The constructor using fields h$>F}n
j
* adON&<
* @param page _B4&Fb.
* @param content .=_p6_G
*/ ]6&NIz`:,
public Result(Page page, List content){ #m+!<
this.page = page; )vr@:PE
this.content = content; ZSMed(//b
} 7*'/E#M
+Qs]8*^?;
/** 1C[9}}
* @return Returns the content. D-3[#~MV
*/ aD/Rr3v>
publicList getContent(){ QaX.Av
return content; #u<Qc T@
} -DDA b(2*
X@nBj;
/** h\m35'v!
* @return Returns the page. [;E%o^/^
*/ $o6/dEKQ
public Page getPage(){ C3AWXO ^
return page; ~PQ.l\C
} ~/:vr
h#rP]o@
/** U%{GLO
* @param content Z1Qz
LvWs
* The content to set. R^Rc!G}
*/ _8K+iqMZG
public void setContent(List content){ T&U}}iWN
this.content = content; e~h>b.~
} a+h$u
J )1
/** 5s7BUT
* @param page @xG&K{j
* The page to set. w+o5iPLX
*/ {N(qS'N
publicvoid setPage(Page page){ }A9#3Y|F
this.page = page; jiI=tg;
} I-v}
DuM
} uf(ayDE
~G@NWF?7
pP\Cwo #,
\u=d`}E
;i{B,!#
2. 编写业务逻辑接口,并实现它(UserManager, H7O~So*N5
%wD#[<BGn>
UserManagerImpl) LPs%^*8(2
java代码: ?2<QoS
68%aDs
_S!^=9bJ
/*Created on 2005-7-15*/ u09Tlqh0 3
package com.adt.service; |jsI-?%8J
W5jwD
import net.sf.hibernate.HibernateException; (qcFGM22U
GT>'|~e
import org.flyware.util.page.Page; :4AQhn^;"
o<g?*"TRh
import com.adt.bo.Result; _K5<)( )
9#E *o~1
/** 1nVQYqT_
* @author Joa ]l7W5$26 @
*/ UBo0c?,4
publicinterface UserManager { uJ`N'`Z
gt4GN`-k
public Result listUser(Page page)throws VO#rJ1J
o.s'0xP]
HibernateException; So5/n7
F`}'^>
} YSjc=
KdNo'*;U]_
+'H[4g`
Q\oa<R
D5
N$=YL
@m8
java代码: P0N/bp2Uy
KFM[caKeJO
iGW(2.Z
/*Created on 2005-7-15*/ !~^2Mu(X
package com.adt.service.impl; m:_#kfC&K"
Quth5
import java.util.List; +U
fw
bR`5g
import net.sf.hibernate.HibernateException; %<i sdvF
5 nt3gVy
import org.flyware.util.page.Page; !D22HSv(w
import org.flyware.util.page.PageUtil; 6v@Prw@.b
<Qq
{&,Le
import com.adt.bo.Result; AArLNXzVW
import com.adt.dao.UserDAO; E2hsSqsu=
import com.adt.exception.ObjectNotFoundException; OPvPP>0*8
import com.adt.service.UserManager; A-x^JC=
at>_EiS
/** QW..=}pL
* @author Joa R ENCk(
*/ (nqhX<T>
publicclass UserManagerImpl implements UserManager { ``xm##K
l@Lk+-[D
private UserDAO userDAO; .+7n@Sc
Y XhZWo{B
/** 6Dd>ex!-A
* @param userDAO The userDAO to set. `(W"wC
*/ R6~6b&-8
publicvoid setUserDAO(UserDAO userDAO){ I!zoo[/)%
this.userDAO = userDAO; mtUiO
p
} XRaGV~
-=-^rQx9
/* (non-Javadoc) l6zAMyau5
* @see com.adt.service.UserManager#listUser ?MDo. z3
d /jx8(0
(org.flyware.util.page.Page) jLFaf#G]
*/ +kI}O*s
public Result listUser(Page page)throws Q-) ( s
$GoS?\G
HibernateException, ObjectNotFoundException { AyJl:aN^
int totalRecords = userDAO.getUserCount(); oy[s])Tg
if(totalRecords == 0)
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throw new ObjectNotFoundException mbAzn
CI+)0=`<1B
("userNotExist"); e"@r[pq-{u
page = PageUtil.createPage(page, totalRecords); q~>!_q]FE
List users = userDAO.getUserByPage(page); zDg*ds\
returnnew Result(page, users); E2Sj IR}
} tFcQ.1
THl:>s
} azZ|T{S
\m`IgP*
=u0=)\0@r
`&I6=,YLp
2NFk#_9e~
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +s}!+I8P
mq{Z
Q'
询,接下来编写UserDAO的代码: s=$xnc}mf
3. UserDAO 和 UserDAOImpl: E[hSL#0
java代码: 2k!uk6
3SM'vV0[
UXZ3~/L5 O
/*Created on 2005-7-15*/ !,-'wT<v
package com.adt.dao; ~N/%R>(v
v~RxtTu
import java.util.List; Ob%iZ.D|3<
X6sZwb
import org.flyware.util.page.Page; M"mvPr9
Zn1((J7
import net.sf.hibernate.HibernateException; ^PdD-tY<
uWGp>;m eO
/** yI=nu53BV
* @author Joa E.yFCaL
*/ 5hqXMs
publicinterface UserDAO extends BaseDAO { +%CXc%
{?
yRO]
publicList getUserByName(String name)throws e_Zs4\^ef
Bl)D/
HibernateException; q2k}bb +
4Zjd g`
publicint getUserCount()throws HibernateException; va~:Ivl-)
&=zJ MGa
publicList getUserByPage(Page page)throws p;[.&oJ
&2@"zD
HibernateException; x8z6 <
mj9|q8v{+
} jKP75jm
G>Bgw>#_
L9[m/(:y
`zs@W
0o6r3xc;
java代码: qoan<z7
wQ-BY"cK\
zBrIhL]95
/*Created on 2005-7-15*/ zv1,DnkqF
package com.adt.dao.impl; `,
|l
uA?a
DjA
import java.util.List; AzGbvBI&V
Jx3a7CpX
import org.flyware.util.page.Page; bz&9]%S<
48gpXcc@|
import net.sf.hibernate.HibernateException; M/[9ZgDc
import net.sf.hibernate.Query; O[ans_8
PzjIM!>
import com.adt.dao.UserDAO; 4pDZ +}p
8=\k<X{`
/** b9f5
* @author Joa Z,3CMWHg
*/ 7|m{hSc
public class UserDAOImpl extends BaseDAOHibernateImpl 4!glgEE*
Rlr[uU_
implements UserDAO { xAsy07J?
gi
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/* (non-Javadoc) rI:]''PR
* @see com.adt.dao.UserDAO#getUserByName OOsd*nX/
8W.-Y|[5?
(java.lang.String) n[-d~ Ce2{
*/ a.<!>o<t:
publicList getUserByName(String name)throws m[5ed1+
5o|u!#6
HibernateException { ]sI{+$~:c
String querySentence = "FROM user in class 5OFb9YX
P.|g4EdND
com.adt.po.User WHERE user.name=:name"; k/xNqN(
Query query = getSession().createQuery :)e/(I]
. Vq_O
u
(querySentence); [yAR%]i-7
query.setParameter("name", name); RML'C:1
return query.list(); Z*5]qh2r8
} el0W0T
YAF0I%PYU
/* (non-Javadoc) 9e1KH'
* @see com.adt.dao.UserDAO#getUserCount() 2LN5}[12]
*/ RK]."m0c~#
publicint getUserCount()throws HibernateException { 0xutG/-&N
int count = 0; _`94CC:
String querySentence = "SELECT count(*) FROM )ULxB'Dm
s@3<]
user in class com.adt.po.User"; wa9{Q}wSa
Query query = getSession().createQuery
XN'X&J
YwM;G
g3
(querySentence); qoD
M!~
count = ((Integer)query.iterate().next hmd, g>J:<
M#>f:_`<
()).intValue(); UUql"$q
return count; _bq2h%G=8
} [26([H
KWV{wW=-
/* (non-Javadoc) }%-`CJ,
* @see com.adt.dao.UserDAO#getUserByPage &-Zg0T&tZ
e.g$|C^$m
(org.flyware.util.page.Page)
o;:a6D`
*/ ph1veD<ZZ
publicList getUserByPage(Page page)throws seH#v
w4+bzdZ
HibernateException { iNs
String querySentence = "FROM user in class V/!8q`lYNJ
&"svt2
com.adt.po.User"; Ec]cCLB
Query query = getSession().createQuery {=d\t<p*n
\oGZM0j
(querySentence); ~#~Kxh
query.setFirstResult(page.getBeginIndex()) Ih95&HsdC
.setMaxResults(page.getEveryPage()); 93y. u<,2;
return query.list(); QSy #k~
} 5k}UXRB?
(iiyptJ
} oM-@B'TK
WYE[H9x1?
|5,q54d(K
g<{W\VOPm
M+^+u 1QQ0
至此,一个完整的分页程序完成。前台的只需要调用 7QRtNYo#\
D &wm7,
userManager.listUser(page)即可得到一个Page对象和结果集对象 oZ~M`yOz.
[OsW
的综合体,而传入的参数page对象则可以由前台传入,如果用 A|@d4+
#H1yjJQ /x
webwork,甚至可以直接在配置文件中指定。 18!0Hl>
z|yC [Ota
下面给出一个webwork调用示例: D058=}^HE
java代码: ~c3CyOab
6q8qq/h)
L+QEFQ:r5
/*Created on 2005-6-17*/ XH2g:$
package com.adt.action.user; TO)wjF_
?z60b=f8
import java.util.List; 5,qfr!hN,
15gI-Qb
import org.apache.commons.logging.Log; TaB35glLY
import org.apache.commons.logging.LogFactory; )f'cy@b
import org.flyware.util.page.Page; y?aOk-TaRA
YKUs>tQ!
import com.adt.bo.Result; Ph.$]yQCc]
import com.adt.service.UserService; J]|-.Wv1
import com.opensymphony.xwork.Action; QkzPzbF"
TZZqV8
/** Xf9VW}`*8
* @author Joa !H,R$3~
*/ zYj8\iER
publicclass ListUser implementsAction{ A HKS
[ N
f=J#mmHw$
privatestaticfinal Log logger = LogFactory.getLog .)u,sYZA|
ScfW;
(ListUser.class); ;mo}$^49*
^ tm,gh
private UserService userService; lTdYPqMi
E(
*$wD
private Page page; $K8ZxH1z@
<v[,A8Q
privateList users; o,Ew7~u
"v~w#\pz7
/* Q.6pmaXrb
* (non-Javadoc) +|(
eP_
* P/Sv^d5=e
* @see com.opensymphony.xwork.Action#execute() WE`Y!
*/ Ra_6}k
publicString execute()throwsException{ .Fh5:WN
Result result = userService.listUser(page); haa[ob6T
page = result.getPage(); CWI(Q`((>
users = result.getContent(); T?7ZF+yo6
return SUCCESS; XX}RbE#4
} qdj,Qz9ly
s bW`
/** Pd^ilRB
* @return Returns the page.
h+ELtf
*/ iAWPE`u4
public Page getPage(){ w>VM--
return page; eVbHPu4
} :fpYraBM
{My/+{eS!?
/** d:=5y)
* @return Returns the users. Z:9"7^+
*/ aCFO]
publicList getUsers(){ -jFt4Q7}8
return users; `<Zp!Hl(j
} Ge[N5N>
3Xf}vdgdM$
/** LfrS:g
* @param page 7ktf =Y
* The page to set. V!3O
1
*/ K}! VY`
publicvoid setPage(Page page){ ] X4A)%i
this.page = page; jcOxtDTSW
} X )g<F
Eh0R0;l5>
/** Y R#_<o
* @param users R^fVwDl\
* The users to set. oXV
*/ U{n
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publicvoid setUsers(List users){ -~v;'zOO
this.users = users; d^WVWk K
} F
~
/{1Q*
Uq0RJ<n
/** 07# ~cVI
* @param userService #ra:^9;Es:
* The userService to set. O\B_=KWDO
*/ oC.:mI
publicvoid setUserService(UserService userService){ K
)1K ]
this.userService = userService; % nP13V]
} pvP|.sw5G
} # TC
x8]F
UFm E`|le
VGA?B@
&T}~h^/t
Yep(,J~'
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, wp-*S}TT
yo") G!BN
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 qA#!3<
XNf%vC>
么只需要: 4=>/x90y
java代码: j!qO[CJJ
'X"@C;q
AAxY{Z-4
<?xml version="1.0"?> kdITh9nx<r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork b qEwi[`
u==bLl=$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- H)G ^ Y1
Elh: %dr Q
1.0.dtd"> X'IW&^kI
6*/0 yGij
<xwork> 5L"{J5R}
| ?~-k[|
<package name="user" extends="webwork- z#SBt`c
8 POrD8B
interceptors"> q[] "`?
uK="#1z cC
<!-- The default interceptor stack name aRC>pK.
|/Am\tk#13
--> 8AOJ'~$
<default-interceptor-ref j^"Z^TEBT
+D* b!5[
name="myDefaultWebStack"/> ABSAle
lnEc5J@c>i
<action name="listUser" \3hhM}6)DM
T""X~+{Z@
class="com.adt.action.user.ListUser"> SVpvx`&kT
<param W> s@fN9
=oV8!d%]
name="page.everyPage">10</param> W r);A{
<result s{2BG9s
k
9R_27F
name="success">/user/user_list.jsp</result> ~Wm`SIV
</action> dMp7 ,{FhF
MP-A^QT
</package> 5-0
2(YZTaY
</xwork> ]m{;yOQdsC
TSt-#c4B
F=EAD3
t7H2z}06=h
G9<pYt{:
@`t)ly#N
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 ZsirX~W<
\_#0Z+pX
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。 no?TEXp*
4r\Sbh
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 l[.*X
x#|=.T
R|Z $aHQ
57'=Qz52
2fT't"gw
我写的一个用于分页的类,用了泛型了,hoho :@I?JSi
hY7Q$B<
java代码: IpXg2QbN
;``*]tY$
+*WE<4"!6
package com.intokr.util; Uq 2Uv
"Q`{+|'=E
import java.util.List; |{k;pfPV
@tdX=\[~
/** Hv>A$x$q
* 用于分页的类<br> sZ{Kl\1@
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0|nvi=4~e|
* VHsuC$3W
* @version 0.01 c@1C|
* @author cheng Z~F% K~(
*/ R|%
3JE0
public class Paginator<E> { yb1A(~
privateint count = 0; // 总记录数 BA' ($D>
privateint p = 1; // 页编号 /7De.O~H
privateint num = 20; // 每页的记录数 MeW8aLr
privateList<E> results = null; // 结果 ;Z:z'';Lm
;TD<\1HJT=
/** Unc;@=c
* 结果总数 W1$B6+}Z0V
*/ u|<Z};a
publicint getCount(){ HNxJ`x~Z~
return count; wa6DJ
} >P/kb fPA
k2sb#]-/}
publicvoid setCount(int count){ :!;BOCTYI
this.count = count; '\H {Y[
} @Ytsb!!
.Ej `!
/** eXx6b~D
* 本结果所在的页码,从1开始 7Av/ZS
* Ne,7[k
* @return Returns the pageNo. PQ. xmg2
*/ a"&@G=M@d
publicint getP(){ J\b,rOI f
return p; 9-eYCg7C|
} zNuiBLxDs
Y=sRVypJ
/** 7=0uG
* if(p<=0) p=1 ndT:,"s
* JXUnhjB,B
* @param p 3}= .7qm
*/ 8Y3c,p/gS>
publicvoid setP(int p){ %+|k>?&z7
if(p <= 0) V7%G?
p = 1; a8rsF
this.p = p; V:9| 9$G
} kEf}yTy
Q4{%)}2$
/** @y[Zr6\z
* 每页记录数量 5(q\x(N
*/ [bUM x
publicint getNum(){ {J%Na&D
return num; YN_#x
} 4,tMaQ
JQYIvo1,Q
/** kXzm
* if(num<1) num=1 'Sppm;?
*/ s+(%N8B
publicvoid setNum(int num){ 3hab51J
if(num < 1) !I-+wc{ss
num = 1; MB"uJUk
this.num = num; V^QKn+/
} 6%H8Qv
4*&x% ~*
/** A@bWlwfl
* 获得总页数 ^_9 ^iL
*/ ?{?mAbc
publicint getPageNum(){ {/uBZ(
return(count - 1) / num + 1; #B8`qFpQC
} F7^8Ej9*a
s0H_Y'
/** fO[X<|9
* 获得本页的开始编号,为 (p-1)*num+1 $SSE\+|3
*/ @;qC% +^
publicint getStart(){ .3?'+KZ,
return(p - 1) * num + 1; >F8&wh'BjY
} Dx$74~2e
`)\_
/** Wv_5sPqLW
* @return Returns the results. fKOm\R47
*/ %1gJOV
publicList<E> getResults(){ I+D`\OSL
return results; nT` NfN
} ;!, ]}2w*X
33J}AK^FE
public void setResults(List<E> results){ 6#T?g7\pyR
this.results = results; p|,K2^?Y
}
2_vE
Ky|Hi3?
public String toString(){ b<