Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 QJsud{ada
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 RPXkf71iM
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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 XOdkfmc+s'
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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 ]0g$3
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分页支持类: -F]0Py8(
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java代码: l'K3)yQEJ
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package com.javaeye.common.util; ,X&(BQj h
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import java.util.List;
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publicclass PaginationSupport { F+lsza
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publicfinalstaticint PAGESIZE = 30; k=7+JI"J
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privateint pageSize = PAGESIZE; `:4\RcTb/
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privateList items; Q9\6Pn ]T
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privateint totalCount; ssWSY(j]
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privateint[] indexes = newint[0]; F1q a`j^'
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privateint startIndex = 0; W=$cQ(x4Z
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public PaginationSupport(List items, int UTThl2=+
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totalCount){ " iKX-VIl
setPageSize(PAGESIZE); TqZ&X|G
setTotalCount(totalCount); DaK2P;WP
setItems(items); PCx] >&
setStartIndex(0); |, Lp1
} a9w1Z4
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public PaginationSupport(List items, int HZG<aY="
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totalCount, int startIndex){ !Q0aKkMfL
setPageSize(PAGESIZE); '(qVA>S
setTotalCount(totalCount); :kaHvf
setItems(items); #Is/j =
setStartIndex(startIndex); 0VA$
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} uPp9
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public PaginationSupport(List items, int 2f=7`1RCD
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totalCount, int pageSize, int startIndex){ 60A
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setPageSize(pageSize); UP*\p79oO
setTotalCount(totalCount); nj@l5[
setItems(items); +dt b~M
setStartIndex(startIndex); !OO{qw(*g
} ckZZ)lW`*
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publicList getItems(){ pFUW7jE
return items; mHnHB.OL
} dWCU Z,6}
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publicvoid setItems(List items){ :Hn*|+'
this.items = items; 3=SN;cn
} D+y_&+&,t
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publicint getPageSize(){ 8:iu 8c$
return pageSize; N@z+h
} EJbFo682
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publicvoid setPageSize(int pageSize){ IO(Y_7
this.pageSize = pageSize; RyxEZ7dC<y
} ~MgU"P>
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publicint getTotalCount(){
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return totalCount; bay7%[BLB
} f\Fk+)e@
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publicvoid setTotalCount(int totalCount){ e2onR~Cf
if(totalCount > 0){ H"_]Hq
this.totalCount = totalCount; q*h1=H52
int count = totalCount / :=0XT`iY
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pageSize; -quWnn/
if(totalCount % pageSize > 0) CQLh;W`Dc
count++; gEE6O%]g
indexes = newint[count]; CUS^j
for(int i = 0; i < count; i++){ D>YbL0K>X~
indexes = pageSize * +>F #{b
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} kRyt|ryWh
}else{ 9O%4x"*PO
this.totalCount = 0; Fe4QWB6\U
} .Fz5K&E=
} C&\vVNV;9
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publicint[] getIndexes(){ UacGq,
return indexes; u%^Lu.l_c
} KAR XC,z
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publicvoid setIndexes(int[] indexes){ h=q%h8
this.indexes = indexes; gc'C"(TO(
} cI)XXb4
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publicint getStartIndex(){ _{EO9s2FG
return startIndex; >.D0McQg
} }OeEv@^
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publicvoid setStartIndex(int startIndex){ 2p( M`@
if(totalCount <= 0) s*g yk
this.startIndex = 0; u_aln[oIv
elseif(startIndex >= totalCount) I#Q
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this.startIndex = indexes Nk-biD/J
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[indexes.length - 1]; 4>4*4!KR}
elseif(startIndex < 0) ~P*t_cpZ
this.startIndex = 0; &gkGH<oaX
else{ i^{.Q-
this.startIndex = indexes \?,'i/c-
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[startIndex / pageSize]; >4:W:;R
} Ae,-.xJ
} x@+m_y
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publicint getNextIndex(){ H|='|k5Y.
int nextIndex = getStartIndex() + 28[dTsd%
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pageSize; 6 ^X$;
if(nextIndex >= totalCount) ;Ef:mr"Nu
return getStartIndex(); 2,nKbE9*
else :&=TE 2
return nextIndex; L~1u?-zu
} >4a@rT/
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publicint getPreviousIndex(){ "(}xIsy
int previousIndex = getStartIndex() - y2V9!
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pageSize; Y&xmy|O#
if(previousIndex < 0) _=Y]ZX`j
return0; t"`LJE._P
else &nk6_{6
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return previousIndex; B$k<F8!%
} 8T'=lTJ
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} n4%|F'ma
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抽象业务类 bz_Zk
java代码: lgZ3=h
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/** FxSBxz<N-A
* Created on 2005-7-12 (Q !4\Gy
*/ <@n/[ +3
package com.javaeye.common.business; Q3#-q>;7
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import java.io.Serializable; h0NM5
import java.util.List; ZLdvzH@'
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import org.hibernate.Criteria; -@%*~^~z'
import org.hibernate.HibernateException; (veGztt
import org.hibernate.Session; SMaC{RPQ
import org.hibernate.criterion.DetachedCriteria; krZ J"`
import org.hibernate.criterion.Projections; v'B++-%
import o)KF+[^
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org.springframework.orm.hibernate3.HibernateCallback; Vg/{;uLAe
import
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org.springframework.orm.hibernate3.support.HibernateDaoS ]#N2:ych
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upport; 9^J8V]X
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import com.javaeye.common.util.PaginationSupport; q{ov62t`
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public abstract class AbstractManager extends Pze$QBNoRd
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HibernateDaoSupport { IpY R
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privateboolean cacheQueries = false; 9i WDEk
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privateString queryCacheRegion; &R/)#NAp
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publicvoid setCacheQueries(boolean I!.o&dk
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cacheQueries){ R8UtX9'*sa
this.cacheQueries = cacheQueries; oK@!yYv
} S =q.Y
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publicvoid setQueryCacheRegion(String .ps'{rl8
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queryCacheRegion){ tfj6#{M5
this.queryCacheRegion = #EAP<h
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queryCacheRegion; 7*y_~H
} blph&[`}I
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publicvoid save(finalObject entity){ %(Sy XZ
getHibernateTemplate().save(entity); a ^<W
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} (E59)z -
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publicvoid persist(finalObject entity){ oabc=N!7r
getHibernateTemplate().save(entity); >|!F.W
} qyv9]Q1
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publicvoid update(finalObject entity){ z`((l#(
getHibernateTemplate().update(entity); NY\q
} jNB|98NN
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publicvoid delete(finalObject entity){ B:)9hF?o@
getHibernateTemplate().delete(entity); Bp6jF2
} R!;tF|]
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publicObject load(finalClass entity, VdQ}G!d
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finalSerializable id){ Q.#@xaX'{`
return getHibernateTemplate().load ,x!P|\w.G{
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(entity, id); MBRRzq%F
} r^-3( 77n
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publicObject get(finalClass entity, m `~/]QQ
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finalSerializable id){ vC[)/w
return getHibernateTemplate().get v5i[jM8
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(entity, id); TAlpy$
} OaRtGJnR
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publicList findAll(finalClass entity){ *O,\/aQ+
return getHibernateTemplate().find("from G^!20`p:
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" + entity.getName()); L)&?$V
} CUfD[un2D
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publicList findByNamedQuery(finalString E.Xfb"]
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namedQuery){ QgO@oV* S
return getHibernateTemplate g
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().findByNamedQuery(namedQuery); +"6_rbeuO
} /Z HuT=j1
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publicList findByNamedQuery(finalString query, dbSIC[q
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finalObject parameter){ {EGiGwpf
return getHibernateTemplate ?~uTbNR
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().findByNamedQuery(query, parameter); o{pQDI {R
} Q\&FuU
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publicList findByNamedQuery(finalString query, BRYhL|d~.
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finalObject[] parameters){ R8P7JY[h
return getHibernateTemplate 9V`/zq?
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().findByNamedQuery(query, parameters); YlwCl4hq
} qEPvV
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publicList find(finalString query){ zm)
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return getHibernateTemplate().find &Z/aM?
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(query); )Q9m,/F
} y[Zl ,v7
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publicList find(finalString query, finalObject vt<r_&+ pJ
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parameter){ I=6\z^:
return getHibernateTemplate().find v+f:VA
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(query, parameter); K@Q_q/(%;
} ^5j|
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public PaginationSupport findPageByCriteria -v.\CtpHv
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(final DetachedCriteria detachedCriteria){ eyf\j,xP&
return findPageByCriteria zJWBovT/
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); EGL1[7It`
} =fG c?PQ
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public PaginationSupport findPageByCriteria -FV$Sne
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(final DetachedCriteria detachedCriteria, finalint $7eO33Bm
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startIndex){ W#87T_7T[
return findPageByCriteria < gB>j\:
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(detachedCriteria, PaginationSupport.PAGESIZE, Jaz|b`KDj
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startIndex); 8Kt_irD
} cZI )lX
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public PaginationSupport findPageByCriteria rq?:I:0
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(final DetachedCriteria detachedCriteria, finalint |&B.YLx
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pageSize, ~L(=-B`Ow
finalint startIndex){ H6(kxpOI\
return(PaginationSupport) FJKW=1=,
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getHibernateTemplate().execute(new HibernateCallback(){ XlIRedZ{
publicObject doInHibernate P.Pw.[:3
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(Session session)throws HibernateException { s2A3.SN
Criteria criteria = Bf!i(gM
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detachedCriteria.getExecutableCriteria(session); Sp$~)f'
int totalCount = KD?~ hpg
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((Integer) criteria.setProjection(Projections.rowCount l<5O\?Vo]
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()).uniqueResult()).intValue(); AujvKQ(
criteria.setProjection R r! PU
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(null); U">J$M@
List items = Nw ;BhBt
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criteria.setFirstResult(startIndex).setMaxResults TxAT ))
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(pageSize).list(); pFi.?|6"
PaginationSupport ps = :q=u+h_
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new PaginationSupport(items, totalCount, pageSize, #-
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startIndex); Gxu
return ps; (pM5B8U
} mqgA
}, true); ^2E\{$J
} ULc oti=,
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public List findAllByCriteria(final )\!_`ob
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DetachedCriteria detachedCriteria){ PD$XLZ
return(List) getHibernateTemplate nIdB,
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().execute(new HibernateCallback(){ MGpP'G:v
publicObject doInHibernate JU+Uzp
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(Session session)throws HibernateException { K] ;`
Criteria criteria = QA?e2kd
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detachedCriteria.getExecutableCriteria(session); N,U<.{T=A
return criteria.list(); SA_5..
} ;u`zZb=,[
}, true); ~EJVlji
} $g&,$7}O_
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public int getCountByCriteria(final D?;8bI%"
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DetachedCriteria detachedCriteria){ _kUf[&
Integer count = (Integer) !K a!f1
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getHibernateTemplate().execute(new HibernateCallback(){ R3+y*<<e
publicObject doInHibernate pvCn+y/U;
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(Session session)throws HibernateException { dL;C4[(N
Criteria criteria = [1{#a {4
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detachedCriteria.getExecutableCriteria(session); Yw7+wc8R
return eytd@-7uX
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criteria.setProjection(Projections.rowCount ,i KEIxA!
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()).uniqueResult(); R
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} xb/L AlJ
}, true); U~!yGj F
return count.intValue(); Fw,'a
} L
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} yVA<-PlS<
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用户在web层构造查询条件detachedCriteria,和可选的 ,\*PpcU
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4wp5ghe
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PaginationSupport的实例ps。 R.n:W;^`
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ps.getItems()得到已分页好的结果集 Wjf UbKg0
ps.getIndexes()得到分页索引的数组 *n9t~t6GHg
ps.getTotalCount()得到总结果数 sg@)IEg</v
ps.getStartIndex()当前分页索引 .iK{=L/(y
ps.getNextIndex()下一页索引 9qyA{
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ps.getPreviousIndex()上一页索引 aH@Ux?-}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 MQD%m ;[s
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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'Q|0lB
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一下代码重构了。 eK_Q>;k5A
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我把原本我的做法也提供出来供大家讨论吧: :U^!N8i"=
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首先,为了实现分页查询,我封装了一个Page类: ]Z/<HP$#
java代码: z#qlu=
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/*Created on 2005-4-14*/ 1pe eecE
package org.flyware.util.page; ex_Zw+n
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/** XXbAn-J
* @author Joa \0&7^
* T
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*/ ^,@!L-<~(b
publicclass Page { SM> V
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/** imply if the page has previous page */ &Nf10%J'<
privateboolean hasPrePage; Tac7+=T
t*<@>] k
/** imply if the page has next page */ DDdMWH^o7
privateboolean hasNextPage; J%|!KQl
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/** the number of every page */ u nE h
privateint everyPage; i:ar{ q
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/** the total page number */ J23Tst#s
privateint totalPage; >;@ _TAF
bn`1JI@S4
/** the number of current page */ D&5>Op4U
privateint currentPage; 1mT3$Z
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/** the begin index of the records by the current d\FBY&C7b
F :"CaDk
query */ YE<_a;yh1
privateint beginIndex; V!!E)I
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*P4G}9B|9:
/** The default constructor */ c_#\'yeW
public Page(){ I!IWmU6FN
3QL I|VpO
} 9NCo0!Fb
Rs@2Pe$3
/** construct the page by everyPage J7q]|9Hus|
* @param everyPage lq2P10j@
* */ IipG?v0z~
public Page(int everyPage){ sQt]Y&_/@
this.everyPage = everyPage; >kK;IF9h
} \!HGkmd
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/** The whole constructor */ c(@V
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public Page(boolean hasPrePage, boolean hasNextPage, r)$(>/[$
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int everyPage, int totalPage, 5mNd5IM
int currentPage, int beginIndex){ <0,c{e
this.hasPrePage = hasPrePage; E. @n Rj#
this.hasNextPage = hasNextPage; ;B[*f?y-
this.everyPage = everyPage; YVy+1q[
this.totalPage = totalPage; C3|(XChqC
this.currentPage = currentPage; Xy{\>}i]N
this.beginIndex = beginIndex; ><odBM-
} j6wdqa9!~
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/** l4c9.'6
* @return ur\v[k=
* Returns the beginIndex. Sp+ zP-3
*/ ~9.0:Fm<
publicint getBeginIndex(){ HorFQ?8
return beginIndex; C[h"w'A2
} (<f`},
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/** 'bN\8t\S
* @param beginIndex BbA7X
* The beginIndex to set. h
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*/ sdq8wn
publicvoid setBeginIndex(int beginIndex){ c]]OV7;)>
this.beginIndex = beginIndex; ?3ldHWa
} o#V}l^uU=
w}="}Cb
/** yyZV/
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* @return D+Osz
* Returns the currentPage. \W5fcxf
*/ .Y}~2n
publicint getCurrentPage(){ *g
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return currentPage; 0pT?qsM2
} U~krv>I
tHezS~t_
/** M*|,05>
* @param currentPage )H&rr(
* The currentPage to set. d(u"^NH;
*/ k&-SB -
publicvoid setCurrentPage(int currentPage){ #'}?.m
this.currentPage = currentPage; Zo}O,;(F5
} .W_'6Q+
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/** #.|efdsG
* @return m22FOjk\
* Returns the everyPage. FsI51@V72Q
*/ QkJAjmB
publicint getEveryPage(){ fi*@m,-
return everyPage; nCF1i2*6|"
} LadE4:oy
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"
/** 9VyY[&
* @param everyPage L;d(|7BVv
* The everyPage to set. 5;{Q >n
*/ p^u;]~JO
publicvoid setEveryPage(int everyPage){ &rY73qfP'
this.everyPage = everyPage; 3o=R_%r
} *3;H6
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/** !]1'?8
* @return 9$)I=Rpk=
* Returns the hasNextPage. :\I88
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*/ |G^w2"D_Z
publicboolean getHasNextPage(){ S>AM?
return hasNextPage; k+
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} F Xbf7G)H
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/** .EJo9s'
* @param hasNextPage DbRq,T
* The hasNextPage to set. G.CkceWRn
*/ .wj?}Fr?97
publicvoid setHasNextPage(boolean hasNextPage){ }=.:bwX5
this.hasNextPage = hasNextPage; Bp
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} M^f+R'Q3
cB,O"-
/** T0=8 U;
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* @return hfUN~89;
* Returns the hasPrePage. /DxaKZ ;b
*/ s,&tD
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publicboolean getHasPrePage(){ sFhmp
return hasPrePage; .UJp#/EHs
} 8|FHr,
/CRZ
/** Aj9<4N
* @param hasPrePage KxZup\\:v
* The hasPrePage to set. hzG+s#
*/ >NL4&MV:
publicvoid setHasPrePage(boolean hasPrePage){ $9LI v
this.hasPrePage = hasPrePage; 7OF6;@<
} v?\Z4Z|f
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/** 6x?3%0Km
* @return Returns the totalPage. *^|.bBG
* AmSrc.
*/ ^*!Tq&Dst|
publicint getTotalPage(){ {<f |h)r
return totalPage; 2`2S94'
} ;3~+M:{2
re\pE2&B
/** ZdcG6IG+
* @param totalPage "n,?)
* The totalPage to set. y2nwDw(xF
*/ Q]n a_'_
publicvoid setTotalPage(int totalPage){ ;"gUrcuY
this.totalPage = totalPage; /)Ga<
} pAZD>15l"
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} o*\Fj}l-
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 -SF*DZ
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个PageUtil,负责对Page对象进行构造: ak_&\'P
java代码: S.^/Cl;aj
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/*Created on 2005-4-14*/ m :M=De
package org.flyware.util.page; 'aLTiF+
luPj'd?
import org.apache.commons.logging.Log; d
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import org.apache.commons.logging.LogFactory; [\41
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/** 7[ 82~jM[
* @author Joa 2.6F5&:($
* ,lsoxl
*/ kim qm
publicclass PageUtil { wO>P<KBU
,m"0Bu2
privatestaticfinal Log logger = LogFactory.getLog Y2Z<A(W
-~PiPYX
(PageUtil.class); .YYLMI
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/** TSPFi0PP
* Use the origin page to create a new page DNu^4#r
* @param page )j^~=Sio.
* @param totalRecords LKx<hl$O
* @return T*'?;u
*/ Q^_*&},V
publicstatic Page createPage(Page page, int }r)T75_1
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totalRecords){ .dM|J'`g
return createPage(page.getEveryPage(), !}[,ODJ4 d
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page.getCurrentPage(), totalRecords); G5R"5d'
} %xH2jf
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/** wE4:$+R};
* the basic page utils not including exception h\@\*Xz<v
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handler jEkO#xI
* @param everyPage qMj'% 5/
* @param currentPage YVpsf8R
* @param totalRecords j-% vLL/
* @return page X:ck
*/ 8^8fUN4<=
publicstatic Page createPage(int everyPage, int ?hXeZB+b4
g$(<wWsU
currentPage, int totalRecords){ ,?OWwm&J
everyPage = getEveryPage(everyPage); wd
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currentPage = getCurrentPage(currentPage); =.sg$VX
int beginIndex = getBeginIndex(everyPage, 3t*e|Ih&j5
;g:!WXd
currentPage); jgz}
int totalPage = getTotalPage(everyPage, yqY nd<K4
$CXMeY{tOo
totalRecords); 0G=bu5
boolean hasNextPage = hasNextPage(currentPage, }u>F}mUa
;aY.CgX
totalPage); 8n[6BF);
boolean hasPrePage = hasPrePage(currentPage); ,"@Tm01os
e\[z Q
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returnnew Page(hasPrePage, hasNextPage, w,,QXJe{Z_
everyPage, totalPage, vq.~8c1
currentPage, fW'@+<b
"X.JD
beginIndex); +p:?blG
} m$bX;F}T
`ZC{<eVJ}=
privatestaticint getEveryPage(int everyPage){ 6c?;-5.
return everyPage == 0 ? 10 : everyPage; _0v+g1x
} :cvZk|b%
B5nzkJV<X
privatestaticint getCurrentPage(int currentPage){ IQ5H`o?[B
return currentPage == 0 ? 1 : currentPage; lJ'.1Z&
} 0L
^WTq
pZYcCc>6&
privatestaticint getBeginIndex(int everyPage, int &EELq"5K
;T9u$4<
currentPage){ 7jj.maK
return(currentPage - 1) * everyPage; R>r@I_
} #dvH0LX?
*Y4[YnkPE
privatestaticint getTotalPage(int everyPage, int d>RoH]K4
p}b:(QN~m
totalRecords){ N FVr$?P
int totalPage = 0; xbN)z
zKY 9'y
if(totalRecords % everyPage == 0) 3N5un`K7
totalPage = totalRecords / everyPage; ??'>kQ4
else 0ESxsba
totalPage = totalRecords / everyPage + 1 ; yFD3:;}
b`lLqV<[cB
return totalPage; #:~MtV
} ],?rFK{O
w ,6zbI/
privatestaticboolean hasPrePage(int currentPage){ k\ 2.\Lwb
return currentPage == 1 ? false : true; ;fdROI
} 'e/= !"T
<]SI-
privatestaticboolean hasNextPage(int currentPage, Z4"SKsJT/>
DE $HF*WY
int totalPage){ dN8@ 0AMSf
return currentPage == totalPage || totalPage == ]c Or$O*
XBmAD!
0 ? false : true; SZ;Is,VgU4
} r?:zKj8/u
T[?toqkD>z
7,.3'cCL^
} \\Z{[{OZ
$4*wK@xu
gsSUm f1
HW@r1[Y
1 m>x5Dbk!
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Cuk!I$
?k}"g$JFn
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 :/.SrkN(A7
:Sd"~\N+
做法如下: C{5bG=Sg~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ac2G;}B|
)~Pj3
的信息,和一个结果集List: H2cY},
java代码: A_ftf7,
m?@0Pf}xa
TA~FP#.
/*Created on 2005-6-13*/ Y\e8oIYu7
package com.adt.bo; ]9 ArT$
,P T5-9 m
import java.util.List; ]E:P-xTwaI
Wifr%&t{J
import org.flyware.util.page.Page; 1Fs:&* =
CkHifmc(u-
/** )M:pg%
* @author Joa n{@^ne4m
*/ 1pDL()t
publicclass Result { oA;> z
7R{(\s\9:
private Page page; ;r1.Uz(
T 8.
to
private List content; ]6*+i $
i+Fk
/** ^]_5oFRIj
* The default constructor zg[.Pws:E
*/ g(b:^_Nep
public Result(){ br[n5
super(); _ft)e3Gf
} @Q%g#N
H+O^e l
/** Wb7z&vj
* The constructor using fields m`Dn R`+
* {T=rsPp<@
* @param page V1
:aR3*!
* @param content h{BO\^6x
*/ NA<6s]Cs.
public Result(Page page, List content){ 'C")X
this.page = page; ~=#jr0IZ
this.content = content; wfJ["
q
} Rc.8j,]
OZc.Rtgc
/** ->0OqVQA
* @return Returns the content. AY~~ a)V
*/ d$O)k+j
publicList getContent(){ \.AI;^)X@]
return content; 8ba*:sb
} SaA9)s
(46S^*
/** y~jYGN
* @return Returns the page. w?db~"T
*/ 1$^=M[v
public Page getPage(){ Ou'<9m!9
return page; \NN5'DBx
} j}devpO
d J;y>_
/** Pp9nilb_(
* @param content c~=yD:$
* The content to set. jh*aD=y
*/ U(t_uc5q
public void setContent(List content){ x.:k0;%Q
this.content = content; ^ 1 P@BRh
} ?{bAyh/
oO8opS7F
/** W2CQk
* @param page Jjgy;*hM
* The page to set. wzka4J {
*/ a!?&8$^<
publicvoid setPage(Page page){ #]@<YKoV{
this.page = page; NX$S^Z\QI
} r@&d88U:
} 9E (VU.
#rZk&q
Tr1#=&N0
yqF$J"=|
nb:J"
2. 编写业务逻辑接口,并实现它(UserManager, Ul?Ha{W
BX|+"AeF
UserManagerImpl) "+REv_:
java代码: =a`l1zn8=
X51 7PT8O
^@
GE1
/*Created on 2005-7-15*/ e&C(IEZ/N;
package com.adt.service; kU8V,5
)$/Gh&1G
import net.sf.hibernate.HibernateException; 2&E1) ^
[?<"SJ,`
import org.flyware.util.page.Page; /3*75
x@F"ZiYD@O
import com.adt.bo.Result; G
1{F_
8k$iz@e
/** R|T_9/#)
* @author Joa M%wj6!5
*/ '|0Dt|$
publicinterface UserManager { 29K09 0f
D?rQQxb
public Result listUser(Page page)throws #&G^%1!
IKM=Q.
7j
HibernateException; z.g'8#@
{m9OgR5U
} &0O1tM*v
5Qp5JMK
b|T}mn
;l_%;O5
,Cg uY/y
java代码: H&65X
. `lcxC
=6t)-53
/*Created on 2005-7-15*/ LSQ2pB2V
package com.adt.service.impl; <lM]c
%-+lud
import java.util.List; /vFw5KUu
_9E7;ew
import net.sf.hibernate.HibernateException; ;m}lmq,
da3]#%i0
import org.flyware.util.page.Page; $4`RJ{ZJw]
import org.flyware.util.page.PageUtil; _pQ9q&i4
guv)[:cd;
import com.adt.bo.Result; ,MwwA@,9-
import com.adt.dao.UserDAO; ZD1UMB0$4
import com.adt.exception.ObjectNotFoundException; g2 uc+p
import com.adt.service.UserManager; x%ZjGDF m
"sz)~Q'W5
/** 8#S|jBV
* @author Joa b0]y$*{j
*/ H~+D2A
publicclass UserManagerImpl implements UserManager { !`vm7FN"u
__""!Yz
private UserDAO userDAO; vBd^=O
t&u,Od
/** OvU]|4h
* @param userDAO The userDAO to set. -IJt( X|
*/ `gy]|gS#b
publicvoid setUserDAO(UserDAO userDAO){ -p`hevRr
this.userDAO = userDAO; KcVCA
} w,]cFT
,,oiL
/* (non-Javadoc) pi? q<p%
* @see com.adt.service.UserManager#listUser 8^ ;[c
)`Tny]M
(org.flyware.util.page.Page) .:c^G[CQ^9
*/ 7|3Z+#|T
public Result listUser(Page page)throws ):eX*
*&>1A A
HibernateException, ObjectNotFoundException { St/Hv[H'[E
int totalRecords = userDAO.getUserCount(); Yt2_*K@rC
if(totalRecords == 0) e J>(SkR:[
throw new ObjectNotFoundException |sHIT<=m
.x$+7$G
("userNotExist"); >t u3m2
page = PageUtil.createPage(page, totalRecords); J'y*;@4l^:
List users = userDAO.getUserByPage(page); kRnh20I
returnnew Result(page, users); x=yBB;&
} b&p*IyJR
wFpt#_fS
} b mZRCvW>A
!1!;}uzt
5)o-$1s A
AV AF!Z
3> -/sii
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +Tde#T&[
^V v7u@y
询,接下来编写UserDAO的代码: ^x%yIS
3. UserDAO 和 UserDAOImpl: ;JA2n\iP,
java代码: >e($T!}Z
?%i|].<-'
Yb]eWLv
/*Created on 2005-7-15*/ *5hg}[n2
package com.adt.dao; !h}x,=`z/
]}i_Nq W)
import java.util.List; V9I5/~0c
@sav8]
import org.flyware.util.page.Page; r^n%PH<
]Hc`<P
import net.sf.hibernate.HibernateException; o?b$}Qrl
P-ys$=
/** -wvrc3F
* @author Joa NwIl~FNK
*/ 'D-eFJ5
publicinterface UserDAO extends BaseDAO { ]L^X}[SH
l131^48U
publicList getUserByName(String name)throws 5Lo{\7%
)/HSt%>
HibernateException; &`0y<0z
(\e,,C%;
publicint getUserCount()throws HibernateException; 0rxlN
[Yp
*^ \xH ,.
publicList getUserByPage(Page page)throws F +D2
xN@
1mwb&j24n3
HibernateException; I{;s.2
q62TYg}
} 79n,bb5
4gG&u33RrE
GQ[:vX`
36@)a5
E[/<AY^@!z
java代码: #b4`Wcrj
~=aGv%vX
Q 6{2@
/*Created on 2005-7-15*/ {UQpD
package com.adt.dao.impl; 6P;IKOv^
wWko9h=|mQ
import java.util.List; 3cBuqQ
AH;0=<n
import org.flyware.util.page.Page; rOm)s'
7h<B:~(K
import net.sf.hibernate.HibernateException; b&"=W9(V
import net.sf.hibernate.Query; BLgmFE2
Y
6K<e:Y
import com.adt.dao.UserDAO; gs_"H
&"BmCDOq
/** _Xlf}BE
* @author Joa _&DI_'5q+
*/ ib /B!?/
public class UserDAOImpl extends BaseDAOHibernateImpl AA;\7;k{
Gn<s>3E
implements UserDAO { Q%o ]&Hdn
Vz1ro
/* (non-Javadoc) OthQ)&pqX
* @see com.adt.dao.UserDAO#getUserByName Wy.2*+5FX0
RnPJ,Z5s&&
(java.lang.String) Us+|L |/
*/ 5JK{dis]k
publicList getUserByName(String name)throws b7E= u0
Bcg\p}
HibernateException { '!]ry<
String querySentence = "FROM user in class oL1m<cQo9
eh2 w7@7Q
com.adt.po.User WHERE user.name=:name"; ,DqI> vx|
Query query = getSession().createQuery n,hHh=.Fu
k|F<?:C
(querySentence); RWP`#(&/&
query.setParameter("name", name); k?0yH$)'t
return query.list(); .n[!3X|d
} kLU$8L
XE[~!
>'
/* (non-Javadoc) {wih)XNY
* @see com.adt.dao.UserDAO#getUserCount() ajq [ID
*/ 1"RO)&
publicint getUserCount()throws HibernateException { &~:b&
int count = 0; EjV,&7o)
String querySentence = "SELECT count(*) FROM iIA5ylf{E
'*MNRduE6
user in class com.adt.po.User";
]hpocr
Query query = getSession().createQuery ` :eXXE
d&&^_0O
(querySentence); 4ZrX=e,
count = ((Integer)query.iterate().next hC4##pAa
rbS67--]
()).intValue(); (s4w0z
return count; %*>=L$A
} !e*Q2H+
Pni
/* (non-Javadoc) t%Vc1H2}
* @see com.adt.dao.UserDAO#getUserByPage y-m<&{q
Z)<ljW
(org.flyware.util.page.Page) %Ui&SZ\
*/ 'e_^s+l)a
publicList getUserByPage(Page page)throws GKu@8Ol-wu
lZ.x@hDS
HibernateException { h-+9Bv]
String querySentence = "FROM user in class 6QkdH7Qf=
v:
cO+dQ
com.adt.po.User"; Uh'3c"
Query query = getSession().createQuery <f%JZ4p*
-"YQo
(querySentence); |'9%vtbM
query.setFirstResult(page.getBeginIndex()) "toyfZq@
.setMaxResults(page.getEveryPage()); }dX[u`zQ
return query.list(); ~McmlJzJG
} 7dyGC:YuTL
-D?T0>
} bq/m?;
YHAhF@&
+ ObP[F
8u
Tq0d6(
/k qW
至此,一个完整的分页程序完成。前台的只需要调用 /{vv n
#|k;nFJ
userManager.listUser(page)即可得到一个Page对象和结果集对象 `% k9@k.
De%WT:v
的综合体,而传入的参数page对象则可以由前台传入,如果用 `9E:V=
VHwb 7f]gq
webwork,甚至可以直接在配置文件中指定。 3/>T/To&2
!G=!^RA
下面给出一个webwork调用示例: MlaViw
java代码: &b8Dy=#
2a8ZU{wjn
vh 5`R/<3
/*Created on 2005-6-17*/ f2ygN6(>
package com.adt.action.user; dP63bV
@8E mY,{;
import java.util.List; Nd'+s>d0
0$NcxbM
import org.apache.commons.logging.Log; LsH&`G^<
import org.apache.commons.logging.LogFactory; 'Vq
<;.A
import org.flyware.util.page.Page; 8dgI&t
j oDY
import com.adt.bo.Result; d2`m0U
import com.adt.service.UserService; ATl.Qku@
import com.opensymphony.xwork.Action; oE\Cwd
nJ'FH['
/** #=C!Xx&
* @author Joa ^kJ(bBY
*/ ^0vK >
publicclass ListUser implementsAction{ z+,l"#Vv
2Z K:S+c
privatestaticfinal Log logger = LogFactory.getLog x>:~=#Vi
*"Yz"PK
(ListUser.class); ,rj_P
Qz)1wf'y
private UserService userService; xj`ni G
.|W0B+Z8
private Page page; e/hA>
f'&30lF
privateList users; ]S;^QZ
dS]TTU1
/* ,l/~epx4v)
* (non-Javadoc) hG51jVYtw
* Lc 4\i
* @see com.opensymphony.xwork.Action#execute() ?#~3%$>
*/ lZ]x #v
publicString execute()throwsException{ tQ0iie1Ys
Result result = userService.listUser(page); ln4gkm<]t
page = result.getPage(); C".nB12
users = result.getContent(); hM$K?t
return SUCCESS; `/?XvF\
} +g/TDwyVH
JLgk?
/** !SRElb A;i
* @return Returns the page. )y>o;^5'
*/ xPMTmx?2
public Page getPage(){ ,dn6z#pb+
return page; IIrh|>d_7
} ?pSb,kN}'
Y' K+O
/** PNy)TqdRS
* @return Returns the users. ,@I_b
*/ B-'oB>|
publicList getUsers(){ (=#[om(A
return users; uP|Py.+
} aY`qb Jy
MI8f(ZJK5
/** ZqT8G
* @param page R\DdU-k
* The page to set. J)(KG dk
*/ 3"v
k$
publicvoid setPage(Page page){ ;Q*=AW
this.page = page; EJC{!06L'/
} )}ygzKEa
}U <T>0
/** uWm,mGd9
* @param users G bW1Lq&"
* The users to set. t~_j+k0K#
*/ `zf,$67>1
publicvoid setUsers(List users){ 2I:x)
this.users = users; %C8p!)Hu
} R(YhVW_l
|#_IAN
/** Tfasry9'8
* @param userService hF m_`J&"
* The userService to set. GD*rTtDWn
*/ ]M^k~Xa
publicvoid setUserService(UserService userService){ i/Zv@GF
this.userService = userService; vbFi#|EU
} yC%zX}5
} w=e_@^Fkx
w5/`_m!
War<a#0
bUv}({
yg}zK>j^vC
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, pF0sXvWGG
Q=B>Q
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 4Js2/s
;/-v4
么只需要: {tS^Q*F
java代码: "&$ [@c
^:krfXT
hA?Flq2QV
<?xml version="1.0"?> 0%x"Va~"z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork hM_0/o-
(RXOv"''=
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~7CQw^"R@
V$ 8go#5
1.0.dtd"> P:lmQHls+
&Tc:WD
<xwork> qg7qTF&
'YQVf]4P
<package name="user" extends="webwork- {@1;kG
uGXN ciEp`
interceptors"> ]o!rK<
nK!yu?mS
<!-- The default interceptor stack name e6G=Bq$
1gK<dg
--> c>SFttbU
<default-interceptor-ref 5Z8Zb.
+qPpPjG;
name="myDefaultWebStack"/> ,\){-H/n
J#1-Le8@
<action name="listUser" U-~6<\Mf
$ ,:3I*}be
class="com.adt.action.user.ListUser"> w^Mj[v#
<param 2SjH7
'
p :v'"A}
name="page.everyPage">10</param> ;+-@AYl
<result S['rfD>9
B|\JGnNQ
name="success">/user/user_list.jsp</result> m8j Q~OS
</action> ]VKM3[
tfKf*Um
</package> LqYP0%7
wOMrUWB0
</xwork> Tasmbo^mAF
95XQ?%
w}20l F
h+\+9^l6|
@PQ%
xcOC7
a-\M)}T
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 "=0(a)01p:
lRk)
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。 h0cdRi
LL0Y$pHV
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 K'6NW:zp~
OfE>8*RI4
Hto RN^9
bHKTCPf
$yn7XonS
我写的一个用于分页的类,用了泛型了,hoho ]NEr]sc-"F
cD%_+@GaU
java代码: S|jE1v"L
0I v(ioB=
`i2:@?Kl9
package com.intokr.util; +UM%6Z=+
$q|-9B
import java.util.List; t6,bA1*5y
8mm]>u$
/** ro n-v"!
* 用于分页的类<br> %#jW
* 可以用于传递查询的结果也可以用于传送查询的参数<br> x]Pp|rHj
* >eC>sTPQ{
* @version 0.01 \PzJ66DL!
* @author cheng =,Zkg(M
*/ hl/) 1sOIR
public class Paginator<E> { F HK{cE
privateint count = 0; // 总记录数 A3uF 0A
privateint p = 1; // 页编号 cb3Q{.-.#
privateint num = 20; // 每页的记录数 ZLGglT'EW>
privateList<E> results = null; // 结果 /g]NC?
IDY2X+C#U
/** !,cLc}a
* 结果总数 QomihQnc
*/ : MEB] }
publicint getCount(){ /ucS*m:<x
return count; #FhgKwx
} mx!EuF$I
8}?wi[T
publicvoid setCount(int count){ 2JhE`EVH
this.count = count; /prR;'ks
} w7%.EA{N
1RgERj
/** jhJ'fI
* 本结果所在的页码,从1开始 FX
%(<M
* !jTxMf
* @return Returns the pageNo. h}U>K4BJ
*/ Wt M1nnJp
publicint getP(){ B'v~0Kau
return p; 3
,f3^A
} .
#FJM2Xk
Y2TXWl,Jk
/** |
9 <+!t\
* if(p<=0) p=1 1KadT7<0}
* @$|8zPs
* @param p "(YfvO+
*/ #z5$_z?_
publicvoid setP(int p){ so>jz@!EE
if(p <= 0) ]@6L,+W"
p = 1; 8~}~d}wW
this.p = p; rU
|%
} 3^,p$D<T:,
!"LFeqI$lr
/** [y&uc
* 每页记录数量 rNoCmNm
*/ 3(,c^F
publicint getNum(){ >H,5MM!
return num; O9P4r*prA
} vhGX&
YM,UM>
/** bcYGkvGbO
* if(num<1) num=1 _)Ad%LPsd7
*/ ^Z+p_;J$p
publicvoid setNum(int num){ w
y&yK*w
if(num < 1) m^o?{
(K
num = 1; 9yK\<6}}QH
this.num = num; 7P:/ (P
} NpH:5hi
Se.qft?D%(
/** r@c!M|m@
* 获得总页数 +TC##}Zmb
*/ F*JbTEOn
publicint getPageNum(){ i.0d>G><@
return(count - 1) / num + 1; 2<E@f0BVAy
} wWVB'MRXB,
tkP& =$
/** [
e#[j{
* 获得本页的开始编号,为 (p-1)*num+1 6t{G{ ]
*/ 4xF}rm
publicint getStart(){ zgl$ n
return(p - 1) * num + 1; s_P[lbHt.
} *>k6n5%
ui80}%
/** Gce[RB:
* @return Returns the results. -XfGF<}r
*/ F8xu&Vk0:
publicList<E> getResults(){ e8&7W3 m
return results;
0v|qP
} $+ORq3
uMjL>YLq{?
public void setResults(List<E> results){ g:YUuZ
this.results = results; H<"EE15
} YbF}>1/"
;!j/t3#a
public String toString(){ }_D{|!!!T
StringBuilder buff = new StringBuilder
&MBm1T|Y
F$S/zh$)0
(); y]g5S-G
buff.append("{"); `('NH]^
buff.append("count:").append(count); l%qfaU2
buff.append(",p:").append(p); Ckhwd
buff.append(",nump:").append(num); AZ
SaI
buff.append(",results:").append ,xutI
M hjIE<OI=
(results); X([@}ren
buff.append("}"); 75iudki
return buff.toString(); & j*Ylj}
} {KSy I#
BkB9u&s^
} X=? \A{Y
| Pqs)Mb]
ypNeTR$4