Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 J'k^(ZZ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ogJ';i/o
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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 (io[O?te
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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 /R>YDout}
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。 ~4mRm!DP
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分页支持类: 8~|v:qk
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java代码: N0 mhgEA
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package com.javaeye.common.util; 1hc`s+N
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import java.util.List; [EK^0g
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publicclass PaginationSupport { `v'yGsIV
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publicfinalstaticint PAGESIZE = 30; @iBmOt>3
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privateint pageSize = PAGESIZE; Kp;a(D
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privateList items; %CUwD
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privateint totalCount; (aq-aum-I
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privateint[] indexes = newint[0]; #wkSru&LS
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privateint startIndex = 0; 2av=W
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public PaginationSupport(List items, int 6:Y2z!MLO
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totalCount){ @twi<U_
setPageSize(PAGESIZE); r>sXvzv
setTotalCount(totalCount); /fU-0a8
setItems(items); EZT 8^m
setStartIndex(0); [*5hx_4%B
} [<d_#(]h'
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public PaginationSupport(List items, int _@g\.7@0G
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totalCount, int startIndex){ *&V"x=ba,
setPageSize(PAGESIZE); cyh;1Q
setTotalCount(totalCount); ,-DU)&dF
setItems(items); !\'HKk~V
setStartIndex(startIndex); xl,6O!aR
} 5'<mfY'B
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public PaginationSupport(List items, int +x~p&,w?
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totalCount, int pageSize, int startIndex){ JgV4-B0
setPageSize(pageSize); !Y/S 2J
setTotalCount(totalCount); APCE}%1U
setItems(items); C^:{y
setStartIndex(startIndex); ~4xn^.w
} ID<[=es6
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publicList getItems(){ w@\4ft6d
return items; kL<HG Qt
} Z>dvth
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publicvoid setItems(List items){ 7f<@+&
this.items = items; Ht@5@(W]I
} *qxv"PptX
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publicint getPageSize(){ #/\Zo &V8
return pageSize; HYZp=*eb
} S>Gb
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publicvoid setPageSize(int pageSize){ o|_9%o52'
this.pageSize = pageSize; (UTA3Db
} WmRu3O
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publicint getTotalCount(){ #vAqqAS`,
return totalCount; V?-2FK]
} M'T[L%AP
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publicvoid setTotalCount(int totalCount){ AKS. XW
if(totalCount > 0){ |:SIyXGbY
this.totalCount = totalCount; ^S)t;t@x
int count = totalCount / mcs!A/]<
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pageSize; 57_AJT hR
if(totalCount % pageSize > 0) Iv u'0vF
count++; _{GD\Ai_W
indexes = newint[count]; 8v=t-GJW
for(int i = 0; i < count; i++){ +WguWLO"
indexes = pageSize * ]Y$jc
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i; AtqsrYj
} :4LWm<P
}else{ l7Wdbx5x0
this.totalCount = 0; oxJAI4{y
4
} J<&?Hb*|
} Q@"!uB.e
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publicint[] getIndexes(){ lg{M\
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return indexes; u)%/df qzZ
} L D%SLJ:
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publicvoid setIndexes(int[] indexes){ tq L2' (=
this.indexes = indexes; ,pUB[w\
} }*vE/W
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publicint getStartIndex(){ t"5ZYa
return startIndex; >D_)z/v?"
} $2a_!/
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publicvoid setStartIndex(int startIndex){ 14(ct
if(totalCount <= 0) j!@,r^(
this.startIndex = 0; `H9!Z$7G
elseif(startIndex >= totalCount) F'@9kdp
this.startIndex = indexes j@4]0o
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[indexes.length - 1];
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elseif(startIndex < 0) n8FIxl&u
this.startIndex = 0; j{/5i`5m
else{ F|P?|
this.startIndex = indexes r&~]6
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[startIndex / pageSize]; ?!3u?Kd
} /PG%Y]l0b
} ^KV:.up6
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publicint getNextIndex(){ 2Tv
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int nextIndex = getStartIndex() + //bQD>NBO
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pageSize; "
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if(nextIndex >= totalCount) 'CRjd~L
return getStartIndex(); []?*}o5&>T
else /74)c~.W
return nextIndex; G\(*z4@Gz
} dki3(
n} ]gAX
publicint getPreviousIndex(){ t$lJgj(
int previousIndex = getStartIndex() - 3(:?Z-iKe
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pageSize; {J/+KK
if(previousIndex < 0) ]1I-e2Q-J
return0; OUN"'p%%
else yvnvI y
return previousIndex; }|RL6p-/'
} m&[(xVM
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} OJ.oHf=K!
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抽象业务类 :J+ANIRI
java代码: LCb0Kq}*/(
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/** L\"eE'A
* Created on 2005-7-12 {#&D=7LP
*/ uI3oPP> $
package com.javaeye.common.business; {
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import java.io.Serializable;
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import java.util.List; GbvbGEG
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import org.hibernate.Criteria; <Rz[G+0S=
import org.hibernate.HibernateException; zv^+8h7k
import org.hibernate.Session; xJOp~fKG
import org.hibernate.criterion.DetachedCriteria; SE$l,Z"[*b
import org.hibernate.criterion.Projections; 6}*4co
import &0{&4,
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org.springframework.orm.hibernate3.HibernateCallback; |Vp
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import `*]r+J2
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org.springframework.orm.hibernate3.support.HibernateDaoS !.O;SG
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upport; <irr.O
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{
import com.javaeye.common.util.PaginationSupport; +u
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public abstract class AbstractManager extends cq/@ng*o
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HibernateDaoSupport { o ,8;=f,7
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privateboolean cacheQueries = false; _9S"rH[
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privateString queryCacheRegion; *]DO3Zw'
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publicvoid setCacheQueries(boolean n+s=u$%qn
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cacheQueries){ Tq8U5#NF
this.cacheQueries = cacheQueries; uTy00`1
} C @P$RVS
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publicvoid setQueryCacheRegion(String +Edq4QYwR
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queryCacheRegion){ +5%ncSJx
this.queryCacheRegion = V! .I>
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queryCacheRegion; G420o}q
} Q=epUHFs
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publicvoid save(finalObject entity){ ixqvX4vv,B
getHibernateTemplate().save(entity); Q0L1!}w
} R,-DP/ (im
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publicvoid persist(finalObject entity){ raM{!T:
getHibernateTemplate().save(entity); UUvR>5@n
} oF s)UR
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publicvoid update(finalObject entity){ _znpzr9H
getHibernateTemplate().update(entity); e_FoNT
} 41+@!`z7
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publicvoid delete(finalObject entity){ pQ8f$I#v
getHibernateTemplate().delete(entity); =
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} g c<Y?a-
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publicObject load(finalClass entity, MQX9BJ%
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finalSerializable id){ 7&Ie3[Rm_3
return getHibernateTemplate().load u\f QaQV
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(entity, id); ]'z 5%'
} `a@YbuLd
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publicObject get(finalClass entity, R!>SN0
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finalSerializable id){ EEHTlqvR
return getHibernateTemplate().get
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(entity, id); /@", 5U#
} ~le:4qaX
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publicList findAll(finalClass entity){ P[H 4Yp
return getHibernateTemplate().find("from {=+'3p
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" + entity.getName()); Kw`}hSE>o
} 5+/XO>P1m|
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publicList findByNamedQuery(finalString A!a.,{fZ
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namedQuery){ +,eF(VS!
return getHibernateTemplate 8P}
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().findByNamedQuery(namedQuery); <"7Wb"+
} Pe@*')o*
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publicList findByNamedQuery(finalString query, eX'V#K#C
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finalObject parameter){ H$6;{IUz~
return getHibernateTemplate M4t:)!dji?
pwNF\ ={
().findByNamedQuery(query, parameter); sTxbh2
} mwF{z.t"
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publicList findByNamedQuery(finalString query, S]gV! Q4%
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finalObject[] parameters){ N\fj[?f[
return getHibernateTemplate Wyb+K)Tg
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().findByNamedQuery(query, parameters); ]5e|W Q>*X
} Hr*xA x
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publicList find(finalString query){ 12}!oS~_
return getHibernateTemplate().find gdg
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(query); R^yh,
} 43!E> mq
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publicList find(finalString query, finalObject (:RYd6i
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parameter){ nlc$"(eA[H
return getHibernateTemplate().find CZkmd
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(query, parameter); Yd<9Y\W%?
} ~8)l/I=`);
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public PaginationSupport findPageByCriteria -.5R.~@
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(final DetachedCriteria detachedCriteria){ GFvLd:p` [
return findPageByCriteria [*r=u[67F
,9$| "e&
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?',GR aD
} ^g"% :4zO
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public PaginationSupport findPageByCriteria zOYG`:/'
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(final DetachedCriteria detachedCriteria, finalint 9r 5(
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startIndex){ SgQ(#y|vV
return findPageByCriteria FMT_X
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(detachedCriteria, PaginationSupport.PAGESIZE, *1*i5c
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startIndex); =Nr?F'<
} >oapw5~5
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public PaginationSupport findPageByCriteria Xc<Hm
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(final DetachedCriteria detachedCriteria, finalint ?2K~']\S
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pageSize, .qCI!%fg
finalint startIndex){ ~NIqO4 D
return(PaginationSupport) _TbvQY
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getHibernateTemplate().execute(new HibernateCallback(){ n
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publicObject doInHibernate %<MI]D
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(Session session)throws HibernateException { f;bVzti+w
Criteria criteria = M`?ATmYy
"||'
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detachedCriteria.getExecutableCriteria(session); Rpxg
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int totalCount = {#z[iiB
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((Integer) criteria.setProjection(Projections.rowCount l7(p~+o?h>
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()).uniqueResult()).intValue(); 27Vx<W
criteria.setProjection CW,|l0i
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(null); I:YE6${k!
List items = !4$-.L)#
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criteria.setFirstResult(startIndex).setMaxResults ESuP ZB
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(pageSize).list(); U}GO* +
PaginationSupport ps = _!%@V=
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new PaginationSupport(items, totalCount, pageSize, xiF}{25a
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startIndex); /Y[ b8f
return ps; $I9U.~*
} /pJr%}sc
}, true); R4S))EHg
} UK.=Y9
}S}%4c>
public List findAllByCriteria(final -$`q:j
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DetachedCriteria detachedCriteria){ BipD8`a
return(List) getHibernateTemplate eH%i8a
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().execute(new HibernateCallback(){ BfQ#5
publicObject doInHibernate
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(Session session)throws HibernateException { >bg{
Criteria criteria = vhN6_XD
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detachedCriteria.getExecutableCriteria(session); {T3wOi
return criteria.list(); 3(1UIu
} 4hW:c0
}, true); tD]vx`0>
} W 2A!BaH%
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public int getCountByCriteria(final 'r}y{`3M
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DetachedCriteria detachedCriteria){ Jjh=zxR>
Integer count = (Integer) VgMuX3=
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getHibernateTemplate().execute(new HibernateCallback(){ Kp6%=JjO
publicObject doInHibernate 3Q_)Xs
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(Session session)throws HibernateException { E/_n}$Z
Criteria criteria = Cm-dos
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detachedCriteria.getExecutableCriteria(session); MF+F8h>/
return x/%/MFK)>8
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criteria.setProjection(Projections.rowCount j{HIdP
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()).uniqueResult(); cK'}+
} ;>Z0e`=
}, true); vH6.;j'^
return count.intValue(); 3
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} th+LScOX
} ~2QD.(
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用户在web层构造查询条件detachedCriteria,和可选的 E-#C#B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /=KEM gI?
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PaginationSupport的实例ps。 AdRK )L
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ps.getItems()得到已分页好的结果集 KnUVR!H|
ps.getIndexes()得到分页索引的数组 !ZayN
ps.getTotalCount()得到总结果数 P#AS")Sj
ps.getStartIndex()当前分页索引 HcHwvf6y
ps.getNextIndex()下一页索引 vP,$S^7$
ps.getPreviousIndex()上一页索引 O*c<m,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Xkf|^-n
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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 P -X2A2
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一下代码重构了。 MK <\:g
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我把原本我的做法也提供出来供大家讨论吧: LVJn2t^
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首先,为了实现分页查询,我封装了一个Page类: c+:^0&l
java代码: ra^"Vr
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/*Created on 2005-4-14*/ eqqnR.0
package org.flyware.util.page; ME*A6/h
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/** o>HGfr,N
* @author Joa |q
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* 2 e&M/{
*/ "1rT>
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publicclass Page { mnU8i=v0A
p+${_w>pl{
/** imply if the page has previous page */ euET)Ccq
privateboolean hasPrePage; b
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/** imply if the page has next page */ p,7?rI\N
privateboolean hasNextPage; ~\ v"xV
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/** the number of every page */ q<4{&omUJ
privateint everyPage; }bnodb^.7
S(_DR8
/** the total page number */ EEiWIf&S,
privateint totalPage; DDZnNSo<JQ
1tl qw
/** the number of current page */ vZXdc+2l
privateint currentPage; @6H 7
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/** the begin index of the records by the current J@qLBe(v
U"a7myB+jX
query */ rGay~\
privateint beginIndex; =sk#`,,:
{5c]\{O?[
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/** The default constructor */ Qki?
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public Page(){ I 1Yr{(ho
Nr`v|_U
} @IOl0db
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/** construct the page by everyPage I^G6aw
* @param everyPage @QF;m
* */ qpq(<
public Page(int everyPage){ t"YN:y8-
this.everyPage = everyPage; #{J+BWP\o
} C2yJ Xi`$
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/** The whole constructor */ 'a"Uw"/p[
public Page(boolean hasPrePage, boolean hasNextPage, q&^H"
fF
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3=%G{L16-
int everyPage, int totalPage, '30JJ0
int currentPage, int beginIndex){ w^}*<q\
this.hasPrePage = hasPrePage; 2%)~E50U
this.hasNextPage = hasNextPage; chM-YuN|
this.everyPage = everyPage; gOy{ RE
this.totalPage = totalPage; o Va[
this.currentPage = currentPage; bl\;*.s'
this.beginIndex = beginIndex; :bXTV?#0
} t|*UlTLm
G^#?~
/** [C@Ro,mI
* @return \p!m/2
* Returns the beginIndex. l|M|;5TW
*/ }Ggn2 X
publicint getBeginIndex(){ -jVg{f!
return beginIndex; $_gv(&ZT
} t<%+))b
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/** )/Oldyp
* @param beginIndex gl!ht@;>ak
* The beginIndex to set. {~#d_!(
*/ uxL3 8d]
publicvoid setBeginIndex(int beginIndex){ 1yTw*vH F
this.beginIndex = beginIndex; /'^BHA|h
} "tu*(>'~5
W!1
B~NH#
/** Ii>#9>!F
* @return 7**zO3
H
* Returns the currentPage. ::@JL
*/ J!}R>mR
publicint getCurrentPage(){ kH=qJ3Z
return currentPage; /9| 2uw`
} 4I2#L+W
rY)m"'puP
/** *Zn,v-d
* @param currentPage "@rHGxK
* The currentPage to set. IG~Zxn1o
*/ ]PbwG
publicvoid setCurrentPage(int currentPage){ v+CW([zAx#
this.currentPage = currentPage;
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} o%K1!'
pE$*[IvQ'
/** y8]vl;88yY
* @return <80M$a
g
* Returns the everyPage. 1 K]
*/ ML%JTx0+Z
publicint getEveryPage(){ 0UQ
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return everyPage; !"'@c
} #q8/=,3EG
_,w*Rv5=
/** FPEab69
* @param everyPage o_ r{cnu
* The everyPage to set. ^$<:~qq!
*/ }{v0}-~@
publicvoid setEveryPage(int everyPage){ 4 &0MB>m
this.everyPage = everyPage; E&Sr+D aPD
} @==
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z]j_,3Hff
/** UN:cRH{?*
* @return HN<e)E38
* Returns the hasNextPage. ?yA
2N;
*/ N<QLvZh
publicboolean getHasNextPage(){ WrR8TYq9D]
return hasNextPage; {(h!JeQ
} 7*4i0{]
5,R<9FjW
/** x( rl|o
* @param hasNextPage x_= 3!)
* The hasNextPage to set. A64c,Uv
*/ |xpOU*k
publicvoid setHasNextPage(boolean hasNextPage){ ,u14R]
this.hasNextPage = hasNextPage; uC2 5pH"
} +\J+?jOC4S
0- u,AD
/** CC]q\%y-_
* @return #?~G\Ux0/
* Returns the hasPrePage. ,Uy~O(Ft
*/ Po.izE!C
publicboolean getHasPrePage(){ P+,YWp
return hasPrePage; #*G}v%Ow/u
} ^;@!\Rc
vQ[ TcV
/** E%$[*jZ
* @param hasPrePage ictOCF
* The hasPrePage to set. xP 3>8Y
*/ SnoEi~Da
publicvoid setHasPrePage(boolean hasPrePage){ ,;yaYF6|/
this.hasPrePage = hasPrePage; t<cWMx5ra
} &pAmFe
IOl0=+p
/** f1t?<=3Ek<
* @return Returns the totalPage. !KHbsOT?9
* 3GZrVhU?m
*/ MED_#OS
publicint getTotalPage(){ a(x#6
return totalPage; 2-:` lrVd
} Bhe0z|&
Y7`Dx'x
/** _Fjax
* @param totalPage RR>G}u9np
* The totalPage to set. M,SIs
3
*/ ^!SwY_>
publicvoid setTotalPage(int totalPage){ x^
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this.totalPage = totalPage; lsVg'k/Z!
} q{7+N1
"
5_SxX@fW%
} qwo{34
^0/!:*?
kqLpt
'he&h4fm
x!UGLL]_M
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 dVBr-+
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个PageUtil,负责对Page对象进行构造: ;AT~?o`n
java代码: ts=+k/Z
wA6<BujD
weIlWxy
/*Created on 2005-4-14*/ )lVplAhZD
package org.flyware.util.page; smX&B,&@
OPDRV\
import org.apache.commons.logging.Log; wodff_l
import org.apache.commons.logging.LogFactory; F/D/1w^ iR
9>d~g!u=
/** xGX U7w:X
* @author Joa u2l`%
F`x
* J(`(PYo\i
*/ aMyf|l.
publicclass PageUtil { ~-NlTx
d C6t+
privatestaticfinal Log logger = LogFactory.getLog o[nr)
E D_J8+
(PageUtil.class); )eBCO~HS
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/** "R-Pe\W
* Use the origin page to create a new page 2}.EFQp+
* @param page ~Yl%{1
* @param totalRecords RaB%N$.9s
* @return n^rzl6dy
*/ $p.0[A(N
publicstatic Page createPage(Page page, int Fh ^Ax3P(
q7zHT=@$
totalRecords){ PL*kjrLu7
return createPage(page.getEveryPage(), vrXNa8,L
ffh3okyW0
page.getCurrentPage(), totalRecords); 2tdr1+U?g
} AO0aOX8_+D
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/** WOf*1C
* the basic page utils not including exception MT.D#jv&
t8S,C4
handler S d]`)
* @param everyPage 2@pEuB3$?!
* @param currentPage 2L?Pw
* @param totalRecords q]z%<`.9*
* @return page 9'h4QF+Y
*/ U9yR~pw
publicstatic Page createPage(int everyPage, int x5!lnN,#
J ?H|"
currentPage, int totalRecords){ P!lTK
everyPage = getEveryPage(everyPage); hgF4PdO1e
currentPage = getCurrentPage(currentPage); Rm=[Sj84
int beginIndex = getBeginIndex(everyPage, %2rUJaOgy$
t0o'_>*?A
currentPage); c`!8!R
int totalPage = getTotalPage(everyPage, [214b=
wTu=v
totalRecords); 7f
q\
H{
boolean hasNextPage = hasNextPage(currentPage, M1=y-3dW3
X:gE
mcXc
totalPage); AO^c=^
boolean hasPrePage = hasPrePage(currentPage); nV?e(}D
j*@EJ"Gm>
returnnew Page(hasPrePage, hasNextPage, /Wm3qlv
everyPage, totalPage, 4(}V$#^+
currentPage, (khMjFOg
F5/,H:K\
beginIndex); kI#yW!
} y
;T=u(}
di#:KW
privatestaticint getEveryPage(int everyPage){ 2W=am_\0e.
return everyPage == 0 ? 10 : everyPage; atjrn:X
} )\0LxsZ
tU(vt0~b
privatestaticint getCurrentPage(int currentPage){ EyPF'|Qtn
return currentPage == 0 ? 1 : currentPage; Z<6Fq*I
} e(sV4Z~
;PG,0R`Z;
privatestaticint getBeginIndex(int everyPage, int ~0XV[$`L
j?9fb
currentPage){ 9/R<,
return(currentPage - 1) * everyPage; }TAHVcX*p
} naWW i]9
zrCQEQq
privatestaticint getTotalPage(int everyPage, int gAViwy9{
>&2n\HR\
totalRecords){ %^66(n)
int totalPage = 0; ao.v]6a
nXcOFU
if(totalRecords % everyPage == 0) d"JI4)%
totalPage = totalRecords / everyPage; P*sb@y>}O
else )K^5+oC17
totalPage = totalRecords / everyPage + 1 ; +UC-
A]"IQ-
return totalPage; 1r;.r|
} <MoKTP-<
@mrGG F
privatestaticboolean hasPrePage(int currentPage){ LzJNQd'
return currentPage == 1 ? false : true; 9<S};I;
} :p,DAt}
Zp*0%x!e
privatestaticboolean hasNextPage(int currentPage, F
B7.b
f1UGDC<p9
int totalPage){ .f]2%utHB
return currentPage == totalPage || totalPage == yu]nK-Y7S
H@pF3gh
0 ? false : true; +~]LvZtI_
} }X[wWH
h$eVhN&Vv
oN6 '%
} CNF3".a
#9)D.d|5
- Ado-'aaS
8st~ O
~g[<A?0=y
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 8rA?X*|S!
&WGG
kn
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 M]$_>&"
`jyBF
做法如下: pJ 7="n
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >rb8A6
#GT4/Ej}W
的信息,和一个结果集List: Jv9yy~
java代码: W6[# q%o
z?i{2Fz6
V[N4 {c
/*Created on 2005-6-13*/ V}UYr Va#9
package com.adt.bo; !K$qh{n
JHZ`LWq
import java.util.List; |ydOi&
X0QLT:J b
import org.flyware.util.page.Page; 9F^rXY.
UjI-<|
/** oDEvhNT
* @author Joa YjM_8@<
*/ C%y!)v_x
publicclass Result { 96$qH{]Ap
#+,O
private Page page; m=uW:~
9!06R-h
private List content; ai,Nx:r
5*W<6ia
/** F ak"u'~
* The default constructor =`MU*Arcs[
*/ v{dvB:KP5X
public Result(){ N}tiaL4
super(); QirS=H+~
} ?pJUbZ#J
;jgJI~3l
/** zU1[+JJY"{
* The constructor using fields @s2<y@
* M:?
:EJ
* @param page f^63<gqY
* @param content S=bdue
*/ hRvjiK\
public Result(Page page, List content){ ?nya;Z-~Hc
this.page = page; .:)nG(7f<
this.content = content; ') -Rv]xe
} )+ss)LEC
vtS[Tkk|A
/** BRg(h3 ED
* @return Returns the content. ^cy.iolt
*/ 'U"ub2j
publicList getContent(){ (?7=$z!h
return content; gZD,#D.hR
} dUg| {l
GcL:plz
/** xJ(4RaP
* @return Returns the page. <!r0[bKz@
*/ /Ky xOb)
public Page getPage(){ LT ZoO9O
return page; &CEZ+\bA
} "}jY;d#n
17nONhh
/** a8Q=_4
l
* @param content 6GZzNhz
* The content to set. u(!@6%?-
*/ J^R#
public void setContent(List content){ (IY=x{b
this.content = content; gADEjr*H
} R} #6
DWQ@]\
/** >pV|c\
* @param page `zJTVi4
* The page to set. SqF9#&F
*/ H[a1n' "<:
publicvoid setPage(Page page){ DfNX@gbo
this.page = page; Mk -Rl
} #~SQujgB
} LK'|sO>|
)+nY-DB(
zu~E}
P;#}@ /E
Uu9*nH_
2. 编写业务逻辑接口,并实现它(UserManager, &u_s*
UaQR0,#0y
UserManagerImpl) :i4>&4j
java代码:
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T!T6M6?
6] ~g*]T
/*Created on 2005-7-15*/ :$`"M#vMX
package com.adt.service; xgi/,Nk '
fA]b'8
import net.sf.hibernate.HibernateException; )aOPR|+
HktvUJ(Ii
import org.flyware.util.page.Page; Y!8Ik(/~i
-2dk8]KB]
import com.adt.bo.Result; <3;Sq~^
) DzbJ}
/** ,c%>M^d
* @author Joa w1je|Oil
*/ Zljj
publicinterface UserManager { *[(}rpp M
xt%-<%s %f
public Result listUser(Page page)throws L;7x2&
T-:
@p>
HibernateException; YmS}*>oz
f,?P1D\
} g?'4G$M
c:/H}2/C
bk**% ]
=c-,uW11[
1?6;Oc^
java代码: [HKTXF{n
f\ wP}c'
<4gT8kQ$x
/*Created on 2005-7-15*/ .."=
package com.adt.service.impl; D=w5Lks
_oB!-#
import java.util.List; @c<*l+Qc
)>]~ Y
import net.sf.hibernate.HibernateException; Wb_'X |"u
Wgt[ACioN
import org.flyware.util.page.Page; 36<PI'l#~
import org.flyware.util.page.PageUtil; C>d_a;pX
z8SrZ#mg
import com.adt.bo.Result; +w
;2k w
import com.adt.dao.UserDAO; A{5^A)$
import com.adt.exception.ObjectNotFoundException; *20$u% z2
import com.adt.service.UserManager; <_S>- ;by
<$^76=x,8P
/** z*cC2+R}=
* @author Joa p*T`fOL
*/ <5s51b <
publicclass UserManagerImpl implements UserManager {
u;fD4CA
.Y8z3O
private UserDAO userDAO; cax]lO
Ylc[ghx
/** )F\tU
* @param userDAO The userDAO to set. bp06xHMu
*/ e5!LbsJv
publicvoid setUserDAO(UserDAO userDAO){ H]LH~l
this.userDAO = userDAO; i )Hjmf3
} $nB4Ie!WcR
y{.s
4NT
/* (non-Javadoc) 4,o|6H
* @see com.adt.service.UserManager#listUser -.8 nEO3
mCa[?
(org.flyware.util.page.Page) }{J5)\s9
*/ l .8@F
public Result listUser(Page page)throws zFy0SzF
wzr3y}fCe
HibernateException, ObjectNotFoundException { u? a*bW
int totalRecords = userDAO.getUserCount(); JmJ8s hq
if(totalRecords == 0)
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throw new ObjectNotFoundException Oy:;v7
"T`Q,
("userNotExist"); xwZcO
page = PageUtil.createPage(page, totalRecords); H'fmQf
List users = userDAO.getUserByPage(page); a9CY,+z5B
returnnew Result(page, users); XwKB+Yj0
} }u=-Y'!#]
6j FD|
} -lKk.Y.}r
nATEv2:G
}uJH!@j
!ejLqb
> .L\ >
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1 m)WM,L
X>Cl{.
询,接下来编写UserDAO的代码: lg)jc3
3. UserDAO 和 UserDAOImpl: rkF]Q_'`t;
java代码: |IbCN
_5F8F4QY`
0XCtw6
/*Created on 2005-7-15*/ $
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package com.adt.dao; iez@j
-^m]Tb<u
import java.util.List; 29(s^#e8A
F;5S2:a@Z
import org.flyware.util.page.Page; g$c\(isY;
YQb43Sh`
import net.sf.hibernate.HibernateException; 'lPt.*Y<u
vf=b5s(7Q
/** <IWO:7*#
* @author Joa I:4m]q b
*/ $F|3VQ~
publicinterface UserDAO extends BaseDAO { [whX),3>
l6^IX0&p
publicList getUserByName(String name)throws f;<qGM.#|
4{?Djnh
HibernateException; 3g!tk9InG
UADD 7d
publicint getUserCount()throws HibernateException; oe<9CK:?>
:J|t! `
publicList getUserByPage(Page page)throws F]e]
& 5!.!Z3
HibernateException; :"Vfn:Q
Uq0GbLjv"
} YK[PC]w
r=Up-(j
PNwXZ/N%
Ob:}@jj
N/ 7Q(^
java代码: E1(2wJ-3"
KkVFY+/)
ZJCD)?]=3
/*Created on 2005-7-15*/ ZP>KHiA
package com.adt.dao.impl; a}~Xns
>syQDB
import java.util.List; HmWU;9Vn+
h,-8(
S
import org.flyware.util.page.Page; tDF=Iqu)a
=D<{uovQB
import net.sf.hibernate.HibernateException; P`JO6O:&
import net.sf.hibernate.Query; kPt9(E]
yi7m!+D3
import com.adt.dao.UserDAO; Z x9oj
dd+[FU
/** =YZyH4eI
* @author Joa bo]xah|."j
*/ u)]]9G
_8
public class UserDAOImpl extends BaseDAOHibernateImpl Z83A1`!.|
RcQo1
implements UserDAO { !&f(Xs
vYT%e:8)q
/* (non-Javadoc) Nqih LUv
* @see com.adt.dao.UserDAO#getUserByName E'|@hL-jn
CAGaZ rx
(java.lang.String) .G"UM>.}d
*/ H-&Z+4 +Xs
publicList getUserByName(String name)throws f9A^0A?c
qd@x#"qT
HibernateException { %1E:rw@
String querySentence = "FROM user in class [ugBVnma
fmuAX w>
com.adt.po.User WHERE user.name=:name"; !+qy~h
Query query = getSession().createQuery b2x8t7%O
FBn`sS8hH
(querySentence); Ep/kb-~-
query.setParameter("name", name); p~ `f.q$'
return query.list(); cVrses^yE
} e0i&?m
y'ZRoakz)
/* (non-Javadoc) u="VJ3
* @see com.adt.dao.UserDAO#getUserCount() 9EryHV|
*/ eGZ{%\PH<
publicint getUserCount()throws HibernateException { a@[y)xa$Z
int count = 0; EAVB:gE
String querySentence = "SELECT count(*) FROM Tvd=EO
oz!;sj{,D
user in class com.adt.po.User"; R)s@2S
Query query = getSession().createQuery <S*o}:iB
Jg I+k Nx
(querySentence); 5ZG-3qj
count = ((Integer)query.iterate().next seT?:PCA
`^t0379e
()).intValue(); Im9^mVe
return count; F8(6P1}E
} \}O'?)(1
ZJL[#}*
/* (non-Javadoc) .}QR~IR'
* @see com.adt.dao.UserDAO#getUserByPage gAcXd<a0
~~h@(2/Q>x
(org.flyware.util.page.Page) jl# )CEx
*/ Y b57Xu
publicList getUserByPage(Page page)throws AL #w
DL&\iR
HibernateException { F1s kI _!
String querySentence = "FROM user in class &5Ai&<q"p
/IDfGAE
com.adt.po.User"; XWQp-H.
Query query = getSession().createQuery joa|5v'
:b^\O
(querySentence); #q`-"2"|
query.setFirstResult(page.getBeginIndex()) 1:I47/
.setMaxResults(page.getEveryPage()); Z-(V fp4
return query.list(); l`s_Id#
} bAIo5lr
+" 4E:9P?
} GT|=Kx$;
!oTF2Q+C
9p
;)s
S^}@X?v
$<jI<vD+:
至此,一个完整的分页程序完成。前台的只需要调用 @+LZSd+I
k@qn'Zi
userManager.listUser(page)即可得到一个Page对象和结果集对象 L&td4`2y
]|cL+|':y
的综合体,而传入的参数page对象则可以由前台传入,如果用 !(=bH"P
K8 Y/sHl
webwork,甚至可以直接在配置文件中指定。 j(Tt-a("z
pVTx#rY
下面给出一个webwork调用示例: ;\yVwur
java代码: $i@~$m7d-
4zyy
2"
(vjnfH
/*Created on 2005-6-17*/ ] -O/{FIv
package com.adt.action.user; F?]nPb|
ejYJOTT{^
import java.util.List; ADoxma@
oi4tj.!J
import org.apache.commons.logging.Log; *c} MI
e'&
import org.apache.commons.logging.LogFactory; D{~mJDUzK
import org.flyware.util.page.Page; 9o7E/wP
Rn={:u4
import com.adt.bo.Result; jBexEdH
import com.adt.service.UserService; bqmOfGM
import com.opensymphony.xwork.Action; SooSOOAx[
Z/=x(I0
/** Pyc/6~?
* @author Joa I~lX53D
*/ ]m0MbA
publicclass ListUser implementsAction{ ,@2d<d]
>SA?lG8f%
privatestaticfinal Log logger = LogFactory.getLog E]PHO\f-m}
7T
\}nX1
(ListUser.class); CrHH Ob
a}l^+
private UserService userService; !@E=\Sm8EV
RH+3x7l
private Page page; 7o?6Pv%HJC
fDo )~t*~
privateList users; `PI,tmv!
WZ}c)r*R
/* "qEHK;
* (non-Javadoc) SJhcmx+
* M%H<F3
* @see com.opensymphony.xwork.Action#execute() &E.ckWf
*/ z@hlN3dg
publicString execute()throwsException{ Yrp
WGK520
Result result = userService.listUser(page); qv<[f=X9|
page = result.getPage(); oy90|.]G
users = result.getContent(); 3{o5AsVv
return SUCCESS; +JE
h7
} <6k5nE h
ol^J-
/** P@LYa_UFsN
* @return Returns the page. 56(S[
*/ XBv:$F.>$
public Page getPage(){ M/
@1;a@\
return page; <\]o#w*:
} ^S*~<0NQ'
f1F#U@U
/** \gferWm
* @return Returns the users. f,Vj8@p)x
*/ w|?<;+
publicList getUsers(){ 1MI/:vy-
return users; R.Xh&@f`
} X
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dwOB)B@{H
/** A=q)kcuy5
* @param page Q:$<`K4)
* The page to set. qn}w]yGW
*/ ,.Ac= "f
publicvoid setPage(Page page){ [pf78
this.page = page; HJT}v/FZ
} 7r#U^d(
-AcLh0pc
/** 0?525^
* @param users
:Rc>=)<7
* The users to set. E[bJ5o**#
*/ k4te[6)
publicvoid setUsers(List users){ .]`L R@qf
this.users = users; E/9h"zowS
} ,a& N1G.
zg,?aAm
/** Rk8>Ak(/
* @param userService }6SfI;
* The userService to set. f Co- ony
*/ Ht,_<zP;
publicvoid setUserService(UserService userService){ qh;ahX~
this.userService = userService; 4PUSFZK?
} w[@>k@=
} 7!Z\B-_,
-MZLkS U
6tXx--Nh
D. !m*oq
4;@|tC|u
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, i_?";5B"
y\&GPr
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 7)sEW#d!
K:&FWl.
么只需要: .ky((
java代码: z+5l:f
t?H.M
kBYZNjSz
<?xml version="1.0"?> UD6D![e
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork (6i)m
c(
1SoKnfz{6
1.0//EN" "http://www.opensymphony.com/xwork/xwork- L<bZVocOb_
Onoi ^MDy
1.0.dtd"> ,@"Z!?e
=qH9<,p`H
<xwork> |5|^[v
L|4kv
<package name="user" extends="webwork- !HyPe"`oL
6@kKr
interceptors"> qa
'YZE`
?eD,\G
<!-- The default interceptor stack name 5^lroC-(x
j&n][=PL
--> Q7oJ4rIP
<default-interceptor-ref <I
.p{Z
rJi;"xF8
name="myDefaultWebStack"/> cbvK;;
WJvD,VMz
<action name="listUser" jT/SZ|S
+!9&E{pmo
class="com.adt.action.user.ListUser"> JEq0 {_7
<param cn1CM'Ru
_[}r2,e
name="page.everyPage">10</param> t]1j4S"pm
<result 6||zwwk'.
MJ^NRT0?b
name="success">/user/user_list.jsp</result>
5|2v6W!e
</action> [9S\3&yoh
No8 ~~
</package> PGZ .\i
kb<Nuw
</xwork> /5M@>A^?'
9An_zrJ%i
fRKO> /OT
n|`L>@aw,
K$_ Rno"
lk8g2H
,
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 g`~c|bx
zh7#[#>t
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。 f&=y\uP]
OMG.64DX .
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 p-n_
">7
.-[uQtyWW
D)z'FOaI
q]Gym 7o
[oN}zZP]
我写的一个用于分页的类,用了泛型了,hoho ^)=c74;;
]UyIp`nV;
java代码: Qo+_:N
l/[0N@r~
%jEdgD%xV
package com.intokr.util; }5dYmny
QW :-q(s
import java.util.List; ^L}fj$
O)C
y4[
/** -.ITcDg
* 用于分页的类<br> -Si'[5@
* 可以用于传递查询的结果也可以用于传送查询的参数<br> U1(<1eTyu
* \.p{~Hv
* @version 0.01 | ZBv;BW
* @author cheng T)Z2=5V
*/ {'dpRq{c|
public class Paginator<E> { |aef$f5
privateint count = 0; // 总记录数 rqk1 F~j|
privateint p = 1; // 页编号 ^yDCX
privateint num = 20; // 每页的记录数
>QRpRHtb
privateList<E> results = null; // 结果 H?tonG.^(
Kd}cf0
/** J \U}U'qP
* 结果总数 S N_!o2F2
*/ ^S!^$d*
publicint getCount(){ sl^i%xJ|l'
return count; ~5$V8yfx h
} g2%&/zq/
X~XpX7d!
publicvoid setCount(int count){ 4"72
this.count = count; *=i|E7Irg
} 7M#2Tze}
~6!{\un
/** !`S?
* 本结果所在的页码,从1开始 |,CWk|G
* ?,e7v.b
* @return Returns the pageNo. c"R`7P
*/ ]5IG00`
publicint getP(){ tU7,nE>p
return p; A2 r1%}{
} )@)wcf!b
FNlzpCT~L
/** ? _36uJo}
* if(p<=0) p=1 "e62g
* NYtp&[s2-
* @param p s>d@=P>R
*/ 5|YpkY
publicvoid setP(int p){ dn/0>|5OF(
if(p <= 0) =fa!"$J3
p = 1; HU]Yv+3
this.p = p; g2L^cP>2
} <)c/PI[j
{U8Sl.
/** "3CQ0
* 每页记录数量 QXx<Hi^ /
*/ nTO,d$!Kp
publicint getNum(){ 4$9WJ~V{
return num; v!(BS,
} xZAc~~9tD
L?!*HS7m
/** Fy^*@&
* if(num<1) num=1
x,YC/J
*/ /CX_@%m}e=
publicvoid setNum(int num){ HRO:U%
if(num < 1) Aat_5p
num = 1; =*0<.Lo':
this.num = num; KK"uSC
} nxH=Ut7{
^t4T8ejn
/** -U;2
b_
* 获得总页数 uPbvN[~t
*/ Ut4cli&cC
publicint getPageNum(){ 5{cbcuG
return(count - 1) / num + 1; <i34;`)b
} B3[;}8u>
PR?Ls{}p\
/** 1~\YJEsb}d
* 获得本页的开始编号,为 (p-1)*num+1 Up?w>ly
*/ v^2q\A-?
publicint getStart(){ c6gRXp'ID
return(p - 1) * num + 1; 1HYrJb,d
} :f (UZmV$
b||
c^f
/** bmN'{09@
* @return Returns the results. dWV.5cViP
*/ !mhV$2&r
publicList<E> getResults(){ ;w";s$
return results; c!l=09a~a+
} ^(7<L<H
!4zSE,1
public void setResults(List<E> results){ V+My]9ki
this.results = results; urmx})=
} !v(j#N< m
C5mq@$6
public String toString(){ SQ7Ws u>T@
StringBuilder buff = new StringBuilder 7i?"akr4
ximW!y7
(); ~bU!4P}4j
buff.append("{"); csP 5R3
buff.append("count:").append(count); ?m5@ 635
buff.append(",p:").append(p); 2(V;OWY(@
buff.append(",nump:").append(num); e1a8>>bcI
buff.append(",results:").append kGm-jh
v|Y:'5`V
(results); guJS;VC6U
buff.append("}"); "w}}q>P+sA
return buff.toString(); ? pq#|PI)
} ^PDz"L<*
\xD.rBbt
} \IB@*_G
vAZc.=+ >
+\~.cP7[