Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 7xwS
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 <rRmbFH#
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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 mrqCW]#u
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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 QMy;?,
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分页支持类: j:)
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java代码: C(?>l.QGw
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package com.javaeye.common.util; S &s7]
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import java.util.List; |rW}s+Kcr
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publicclass PaginationSupport { 6x*ImhQ.J
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publicfinalstaticint PAGESIZE = 30; H$(%FWzQ%
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privateint pageSize = PAGESIZE; H!Uy4L~>
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privateList items; .X_k[l 9
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privateint totalCount; n3isLNvIp
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privateint[] indexes = newint[0]; j[wGR_EE
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privateint startIndex = 0; T*k
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public PaginationSupport(List items, int G{+sC2
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totalCount){ ?h1]s&^|2
setPageSize(PAGESIZE); 0x[vB5R
setTotalCount(totalCount); aWOApXJ
setItems(items); FK@rZP
setStartIndex(0); f*W<N06EZ
} Kk9 JZ[nT'
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public PaginationSupport(List items, int )l[ +7
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totalCount, int startIndex){ wC@4`h\U
setPageSize(PAGESIZE); .s7o$u~l
setTotalCount(totalCount); e3)rF5pp
setItems(items); ~}83\LI}
setStartIndex(startIndex); 2x$\vL0
} kRSu6r9
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public PaginationSupport(List items, int 5_G7XBvD/w
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totalCount, int pageSize, int startIndex){ UupQ*,dJ
setPageSize(pageSize); ,o*b-Cv/
setTotalCount(totalCount); 47`{ e_YP0
setItems(items); t( p
setStartIndex(startIndex); =*"Amd,
} gTO%
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publicList getItems(){ ;S,g&%N
return items; -Ah \a0z
} 1hi^
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publicvoid setItems(List items){ 9dqD(S#C;"
this.items = items; -}4 H'%Z(i
} F3';oyy
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publicint getPageSize(){ !Q#u
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return pageSize; PeTA:MW
} 6<rc]T'|
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publicvoid setPageSize(int pageSize){ n$#^gzU4
this.pageSize = pageSize; HAGWA2wQ
} /R9>\}.yJ
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publicint getTotalCount(){ 9FPl
return totalCount; -cY/M~
} q.Z0Q
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publicvoid setTotalCount(int totalCount){ I0Wn?Qq=@
if(totalCount > 0){ Haq23K
this.totalCount = totalCount; eUF PzioW
int count = totalCount / M 80U s.
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pageSize; r)U9u 0
if(totalCount % pageSize > 0) pxDZ}4mOh
count++; &(Xp_3PO
indexes = newint[count]; d{ OY
for(int i = 0; i < count; i++){ ->8n.!F}
indexes = pageSize * G=yQYsC$
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} 4XX21<yn
}else{ M7jDV|Go
this.totalCount = 0; R8":1 #&
} c!w4N5aM
} !ZSC"
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publicint[] getIndexes(){ >A2&
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return indexes;
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} hrEKmRmF-
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publicvoid setIndexes(int[] indexes){ 3b%y+?-{\u
this.indexes = indexes; W=F?+KgL
} [0)iY%^
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publicint getStartIndex(){ W{Nhh3
return startIndex; QbOmJQ
} QD\S E
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publicvoid setStartIndex(int startIndex){ 3 5|5|ma
if(totalCount <= 0) *dUnP{6 g
this.startIndex = 0; DrMcE31
elseif(startIndex >= totalCount) w
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this.startIndex = indexes [DjdR_9*I
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[indexes.length - 1]; W]6Y
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elseif(startIndex < 0) #n~/~*:i92
this.startIndex = 0; #;?z<
else{ L$7v;R3
this.startIndex = indexes sjShm
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[startIndex / pageSize]; 9J2%9,^
} C_'Ug
} {&K#~[)
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publicint getNextIndex(){ (CuaBHR
int nextIndex = getStartIndex() + ^IQC:21
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pageSize; 1*>a
if(nextIndex >= totalCount) *pI3"_
return getStartIndex(); 2"V?+Hhz
else #c?\(qjWA
return nextIndex; +=O8t0y
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} rl4daV&,U
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - 7cvbYP\<lv
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pageSize; ,JVD ;u
if(previousIndex < 0) }\l5|Ft[!
return0; QD"V=}'?
else Q@]#fW\Y
return previousIndex; M%9PVePOe
} k}jH
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} : 2?i9F0_
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抽象业务类 W.0dGUi*
java代码: VQqEsnkz
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/** 4fpz;2%
* Created on 2005-7-12 B.&q]CAv-
*/ z,DEBRT+
package com.javaeye.common.business; 0>E` 9|
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import java.io.Serializable; OBb
import java.util.List; ,h> 0k`J:a
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import org.hibernate.Criteria; ,ci
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import org.hibernate.HibernateException; JrCm >0g
import org.hibernate.Session; Fz>J7(Y.j
import org.hibernate.criterion.DetachedCriteria; dc%+f
import org.hibernate.criterion.Projections; Is?0q@
import 6ng
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org.springframework.orm.hibernate3.HibernateCallback; fE_QB=9 cz
import ApS/,cV
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org.springframework.orm.hibernate3.support.HibernateDaoS u-j Gv| ,|
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upport; VCvuZU{<
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import com.javaeye.common.util.PaginationSupport; =I7#Vtd^K<
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public abstract class AbstractManager extends O'$:wc#
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HibernateDaoSupport { Ng+k{vAj
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privateboolean cacheQueries = false; HjV83S;
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privateString queryCacheRegion; W13$-hf9
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publicvoid setCacheQueries(boolean JH<q7Y6!y
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cacheQueries){ PtmdUHvD
this.cacheQueries = cacheQueries; D!)'c(b
} FV:{lC{h~
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publicvoid setQueryCacheRegion(String rD<@$KpP
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queryCacheRegion){ +2C:]
this.queryCacheRegion = e2/&X;2
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queryCacheRegion; [/5>)HK} C
} `iQyKZS/+
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publicvoid save(finalObject entity){ $WTu7lVV[1
getHibernateTemplate().save(entity); #2x\d
} ~Bj-n6 QDE
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publicvoid persist(finalObject entity){ {b]WLBy
getHibernateTemplate().save(entity); d \0K3=h
} _!w# {5~
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publicvoid update(finalObject entity){ =X-$kk
getHibernateTemplate().update(entity); 0~n=|3*P
} CBi
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publicvoid delete(finalObject entity){ D2?~03c
getHibernateTemplate().delete(entity); f+L )x
} #4d0/28b
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publicObject load(finalClass entity, )"j_NlO
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finalSerializable id){ Hhfqb"2on
return getHibernateTemplate().load 80:na7$)#
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(entity, id); Cn+TcdHX
} c;(}Ih(#
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publicObject get(finalClass entity, rQ~%SUM7
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finalSerializable id){ SM0=
return getHibernateTemplate().get uQpV1o5iA
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(entity, id); &/a/V
} d{9jd{
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publicList findAll(finalClass entity){ w3,QT}W vY
return getHibernateTemplate().find("from PksHq77
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" + entity.getName()); QN*'MA"M
} tJ'U<s
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publicList findByNamedQuery(finalString )c+ZQq
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namedQuery){ t%N#Yh!
return getHibernateTemplate %H%>6z x
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().findByNamedQuery(namedQuery); ]9b*!n<z
} H(
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publicList findByNamedQuery(finalString query, p?6w/ n
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finalObject parameter){ :5C9uW#
return getHibernateTemplate GT#i Y*
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().findByNamedQuery(query, parameter); :)mV-(+o
} t'R&$;z@b
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publicList findByNamedQuery(finalString query, 1/j}VC
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finalObject[] parameters){ <3ovCqa
return getHibernateTemplate mlIc`GSI
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().findByNamedQuery(query, parameters); & ({X9
} ihs@
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publicList find(finalString query){ vgsu~(L;
return getHibernateTemplate().find IvH0sS`F
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(query); bha_bj
} ~Dgui/r9J
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publicList find(finalString query, finalObject |)GE7y0Q
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parameter){ ]NsbV
return getHibernateTemplate().find 3}Uae#oy
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(query, parameter); 2Ni2Gkf@
} =}_c=z?UY
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public PaginationSupport findPageByCriteria &bA;>Lu#|o
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(final DetachedCriteria detachedCriteria){ `Mp]iD{
return findPageByCriteria 8 rnr>Ee@
"f5u2=7 }
(detachedCriteria, PaginationSupport.PAGESIZE, 0); VZw( "a*TB
} >;0z-;k6
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public PaginationSupport findPageByCriteria 9u"im+=:
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(final DetachedCriteria detachedCriteria, finalint Z#^2F8,]
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startIndex){ S@Jl_`<
return findPageByCriteria 85Ms*[g
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(detachedCriteria, PaginationSupport.PAGESIZE, /T*{Mo{B
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startIndex); Q7`zrCh
} .8fOc.h8h
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public PaginationSupport findPageByCriteria ou96
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(final DetachedCriteria detachedCriteria, finalint 24|:VxO
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pageSize, +.[#C5
finalint startIndex){ gy~M]u{
return(PaginationSupport) :n>:*e@w%
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getHibernateTemplate().execute(new HibernateCallback(){ 7.akp
publicObject doInHibernate |
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(Session session)throws HibernateException { (?q]E$
@
Criteria criteria = 5C{X$7u
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detachedCriteria.getExecutableCriteria(session); yTbBYx9Bi
int totalCount = @WFjM
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((Integer) criteria.setProjection(Projections.rowCount L'z?M]
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()).uniqueResult()).intValue(); QT^(
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criteria.setProjection I]ywO4
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(null); :sM|~gT
List items = ("mW=Ln
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criteria.setFirstResult(startIndex).setMaxResults t1IC0'o-
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(pageSize).list(); {zmo7~=
PaginationSupport ps = ed*=p
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new PaginationSupport(items, totalCount, pageSize, ^<sX^V+{
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startIndex); x7{,4js
return ps; QR79^A@5
} &tp5y}=n
}, true); ~x>IN1Vci
} 0fNWI
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public List findAllByCriteria(final _H:SoJ'
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DetachedCriteria detachedCriteria){ xp><7{
return(List) getHibernateTemplate ?55('+{l
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().execute(new HibernateCallback(){ EA?:GtH
publicObject doInHibernate qWQJ>
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(Session session)throws HibernateException { >+1^X eeS
Criteria criteria = c WK@O>
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detachedCriteria.getExecutableCriteria(session); RTF{<,E.UX
return criteria.list(); /j3oHi$
} X2sK<Qluql
}, true); Hk3HzN3
} gxt2Mq;q~}
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public int getCountByCriteria(final eb.`Q+Gb
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DetachedCriteria detachedCriteria){ *7!}[ v_
Integer count = (Integer) u%ih7v!r\
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getHibernateTemplate().execute(new HibernateCallback(){ oJXZ}>>iT
publicObject doInHibernate tDIzn`$z
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(Session session)throws HibernateException { hhYo9jTHW
Criteria criteria = |a^ydwb
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detachedCriteria.getExecutableCriteria(session); Q Z9)uI
return `.[hOQ7
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criteria.setProjection(Projections.rowCount nJ2l$J<
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()).uniqueResult(); h3O5DP6~
} i_gS!1Z2
}, true); f_;3|i
return count.intValue(); %!YsSk,
} ocL
} Z< uwqA
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用户在web层构造查询条件detachedCriteria,和可选的 PB }$.8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;5y!,OF6
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PaginationSupport的实例ps。 _>3GNvS
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ps.getItems()得到已分页好的结果集 FVF:1DT
ps.getIndexes()得到分页索引的数组 2hU4g
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ps.getTotalCount()得到总结果数 )%#hpP M^
ps.getStartIndex()当前分页索引 a#G7pZX/I}
ps.getNextIndex()下一页索引 ts9N$?0:V
ps.getPreviousIndex()上一页索引 %>24.i"l
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 hoU&'P8
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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 lG jdDqi
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一下代码重构了。 U/jJ@8
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我把原本我的做法也提供出来供大家讨论吧: u&pLF%'EQ
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首先,为了实现分页查询,我封装了一个Page类: gvwR16N
java代码: @^;\(If2
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/*Created on 2005-4-14*/ p&ow\AO
package org.flyware.util.page; P#EqeO
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/** e@F&/c
* @author Joa yChC&kX
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* 7a@V2cr@
*/ ,ew<T{PL
publicclass Page { ",~3&wx
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/** imply if the page has previous page */ < u^41
privateboolean hasPrePage; ! '2'db
u#
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/** imply if the page has next page */ }Pw5*duq
privateboolean hasNextPage; lzxn} TO}
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/** the number of every page */ iB]kn(2C
privateint everyPage; B /Dj2
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/** the total page number */ z{ymVd0#
privateint totalPage; ;7 IVg[f
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/** the number of current page */ EH,uX{`e
privateint currentPage; YW/<. 0rI
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/** the begin index of the records by the current U*6-Y%7
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query */ UejG$JyHP
privateint beginIndex; B]]M?pS
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/** The default constructor */ 4@8i,q>
public Page(){ 0udE\/4!^
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} kdWi!Hp
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/** construct the page by everyPage 4Y-9W2s
* @param everyPage 71)HxC[6vA
* */ /&kTVuN"(
public Page(int everyPage){ Z2
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this.everyPage = everyPage; "%}PVO!
} I7[+:?2
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/** The whole constructor */ *b7v)d#
public Page(boolean hasPrePage, boolean hasNextPage, hcN$p2-
<BO|.(ys
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int everyPage, int totalPage, ~xHr/:
int currentPage, int beginIndex){ 2b3*zB*@V
this.hasPrePage = hasPrePage; *nH ?o* #
this.hasNextPage = hasNextPage; 4vy!'r@
this.everyPage = everyPage; Hq%`DWus\
this.totalPage = totalPage; &"L3U
this.currentPage = currentPage; y"){?
this.beginIndex = beginIndex; (:hPT-1
} Gt 2rJ<>
}. ,xhF[
/** 3w^q 0/GD
* @return i\`[0dfY
* Returns the beginIndex. {8UBxFIM(
*/ ^U`[P@T
publicint getBeginIndex(){ 0<^K0>lm
p
return beginIndex; g8vN^nQf[
} gzC\6ca
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/** J 0s8vAs
* @param beginIndex p*dez!
* The beginIndex to set. 3Um\?fj>}(
*/
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publicvoid setBeginIndex(int beginIndex){ ,:,c
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this.beginIndex = beginIndex; 9OTw6
} 0J_Np
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/** 6aj)Fe'2
* @return #G]s.by('
* Returns the currentPage. O:u^jcXA
*/ <89js87
publicint getCurrentPage(){ TuX#;!p6
return currentPage; lSbAZ6
} }7&;YAt
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/** i#Wl?(-i
* @param currentPage VW'e&v1 .
* The currentPage to set. DVCc^5#
*/ uQ&xoDCB
publicvoid setCurrentPage(int currentPage){ 4q~l?*S
this.currentPage = currentPage; nkG 6.
} Tl25t^Y
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/** 1`h`-dqr#
* @return );$~/H4
* Returns the everyPage. *emUQ/uvf
*/ P~]BB.tog
publicint getEveryPage(){ qOk4qbl[
return everyPage; N5~g:([k
} x.45!8Zb
q4U?}=PD
/** Ujw^j
* @param everyPage Rfgc^ 3:j
* The everyPage to set. e[{LNM{/#
*/ C\}m_`MR
publicvoid setEveryPage(int everyPage){ ty7a&>G
this.everyPage = everyPage; )iEK7d^-
} ;E##bdSCA
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/** fV;&Ag*ZiV
* @return BT`6v+,h7k
* Returns the hasNextPage. VQLo
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*/ =D3Y
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publicboolean getHasNextPage(){ 3`="4
return hasNextPage; bz<wihZj
} xu_Tocvop
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/** iRPd=)
* @param hasNextPage @++
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* The hasNextPage to set. SX*os$
*/ N7Ne
publicvoid setHasNextPage(boolean hasNextPage){ (/FPGYu3h
this.hasNextPage = hasNextPage; b;S~`PL
} i(Y P(8
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/** FJ#V"|}
* @return `~*qjA
* Returns the hasPrePage. ?VReKv1\
*/ f^0vkWI2
publicboolean getHasPrePage(){ }3N8EmS
return hasPrePage; `uGX/yQ#=
} 7p2x}[ .\
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/** {Y\hr+A
* @param hasPrePage ,`H=%#
* The hasPrePage to set. 'jmcS0f
-
*/ N}s[0s
publicvoid setHasPrePage(boolean hasPrePage){ NUm3E4
this.hasPrePage = hasPrePage; BHU(Hd
} Z.,Pl
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/** %OW[rbE.
* @return Returns the totalPage. \r<&7x#j
* `W|2Xi=^5
*/ b_][Jye&P
publicint getTotalPage(){ s{A-K5S
return totalPage; ^\_`0%`>
} >-oa`im+
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/** xazh8X0P
* @param totalPage zwAuF%U
* The totalPage to set. YS~\Gls%
*/
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publicvoid setTotalPage(int totalPage){ e2Xx7*vS
this.totalPage = totalPage; m#8KCZS
} BNaZD<<
in B}ydk
} KF7f<
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yhUc]6`V.H
IK}T.*[
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 =m-_0xo
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个PageUtil,负责对Page对象进行构造: )vPce
java代码: .W?POJT
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/*Created on 2005-4-14*/ $aGK8%.O
package org.flyware.util.page; 5%G++oLXf
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import org.apache.commons.logging.Log; Bt.W_p
import org.apache.commons.logging.LogFactory; n>iPAD
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/** #=$4U!yL
* @author Joa a^sR?.+3
* F3 wRHq
*/ M2V.FYV{j>
publicclass PageUtil { 3ON]c13
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privatestaticfinal Log logger = LogFactory.getLog /:%^Vh3XF
0.+iVOz+Y
(PageUtil.class); XY%8yII6
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/** 0A}'.LI
* Use the origin page to create a new page -'YX2!IU,
* @param page crvWAsm
* @param totalRecords yy#Xs:/
* @return R~c(^.|r
*/ J-X5n 3I&
publicstatic Page createPage(Page page, int L8Z?B\
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totalRecords){ -"a]) -
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return createPage(page.getEveryPage(), e348^S&rG
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page.getCurrentPage(), totalRecords); \,(t P:o
} E}a3. 6)p
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/** OU{PVF={
* the basic page utils not including exception 9jvg[H
/M'b137
handler m"v` E7G
* @param everyPage Ufo-AeQo
* @param currentPage =`/X
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* @param totalRecords )6AOP-M.9
* @return page dxASU|Yo9
*/ TyK;
q{
publicstatic Page createPage(int everyPage, int <F!:dyl
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currentPage, int totalRecords){ +{#BQbx6
everyPage = getEveryPage(everyPage); Q'\jm=k
currentPage = getCurrentPage(currentPage); $G=\i>R.
int beginIndex = getBeginIndex(everyPage, WMI/Y9N
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currentPage); ?X:RrZ:/
int totalPage = getTotalPage(everyPage, wvq<5gy}
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totalRecords); 6XX5K@
boolean hasNextPage = hasNextPage(currentPage, [KjQW/sb'
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totalPage); oxad}Y
boolean hasPrePage = hasPrePage(currentPage); m:"2I&0)WM
g@j:TQM_0
returnnew Page(hasPrePage, hasNextPage, \64(`6>
everyPage, totalPage, 2_Pe/
currentPage, #}jf TM
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beginIndex); t@4vEKw?.X
} C{>?~@z&5
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privatestaticint getEveryPage(int everyPage){ zZE?G:isR
return everyPage == 0 ? 10 : everyPage; -R\}Q"
} )s^XVs.-
L\"=H4r
privatestaticint getCurrentPage(int currentPage){ tL
IE^
return currentPage == 0 ? 1 : currentPage; ' u0{h
} HX
<;=m
+SP5+"y@
privatestaticint getBeginIndex(int everyPage, int ;M JM~\L0
1}'Jbj"/
currentPage){ QeQbO
return(currentPage - 1) * everyPage; X5<L
} bqLv81 V
:m+:%keK
privatestaticint getTotalPage(int everyPage, int W``e6RX-
")o.x7~N
totalRecords){ $iF7hyZ
int totalPage = 0; 5aWKyXBIx
z&-`<uV~
if(totalRecords % everyPage == 0) h?CNChRJs
totalPage = totalRecords / everyPage; t8^*s<O
else 9(B)
totalPage = totalRecords / everyPage + 1 ; 'dht5iI;Yw
oiR`\uY
return totalPage; v=W%|iZ
} #u2PAZ@qd
"<.b=mN-
privatestaticboolean hasPrePage(int currentPage){ V5A7w
V3~
return currentPage == 1 ? false : true; yBr{nFOgdY
} 4H " *.l
Nd6N:1-
privatestaticboolean hasNextPage(int currentPage, ;N,7#l|wi
"n05y}
int totalPage){ km3-Hp1
return currentPage == totalPage || totalPage == xbmOch}j6
z?i82B[Tm
0 ? false : true; _e-a>y
} @{$SjR8Q $
i?|SC=
1-b,X]i
} I]$kVa1iN
,$G89jSM
"iKK&%W
CP?\'a"Kt
m.4y=69 &
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。 Q.8Jgel1
* dNMnZ@Y
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 ,Y&kW'2
=lffr?#&B
做法如下: c''!&;[!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D1Fc7!TV
J}.p6E~j
的信息,和一个结果集List: #:{u1sq;
java代码: aH>.o 1;
55[K[K
vR`KRI`{
/*Created on 2005-6-13*/ 4b<:67
%
package com.adt.bo; _mO\Nw0
*qR
tk
import java.util.List; mqE&phF,
fj"S|]e
import org.flyware.util.page.Page; nGuF,0j
WIhf*LF"
/** ?Dfgyz
* @author Joa *X)OdU
*/ B)c.`cfr*\
publicclass Result { _]Hn:O"o
2[:`w),.
private Page page; h<QXr'4+
}ShZ4 xMz
private List content; g:*yjj
AU7c =
H:?
/** [PU.lRq
* The default constructor 7%F9.h
*/ $AX!L+<!
public Result(){ .rMGI"
super(); y%T'e(5Ed
} 9> (8r+
M2m@N-+R
/** ",K6zALJ
* The constructor using fields w)}[)}T!
* %iX+"
* @param page 8
{QvB"w
* @param content =6%0pu]0
*/ PVvG
public Result(Page page, List content){
k&rl%P
this.page = page; }2{%V^D)r
this.content = content; [NuayO3
} uH7u4f1Q
iKdC2m
/** Cx@, J\rsQ
* @return Returns the content. 'DKP-R"
*/ {j(,Q qB;f
publicList getContent(){ 6x.#K9@q4
return content; B,A/
-B\
} ,iHl;3bu
MbJV)*Q
/** /]vg_&)=
* @return Returns the page. %i96@6O
*/ &yP9vp="
public Page getPage(){ N2~Nc"L
return page; XCk \#(VSE
} xo]|m\#k5E
g{nu3F}8){
/** 2R)Y}*VX
* @param content le1'r>E$
* The content to set. /FQumqbnt
*/ gsZCWT
public void setContent(List content){ 2B*9]AHny
this.content = content; JNsK
} 8S)k]$ wf%
jd$lu^>I
/** x0 j$]$
* @param page g#H#i~E^
* The page to set. hd '!f
*/ j:fL_1m
publicvoid setPage(Page page){ _w'4f )7
this.page = page; Ye,E7A*L
} Z*leEwgz
} M~^|dR)D
9((v.
Hm*n,8_
+nZx{d,wt
!,I}2,1%k
2. 编写业务逻辑接口,并实现它(UserManager, ,(]hykbXp
F*(<`V
UserManagerImpl) m 'a3}vRV(
java代码: TMq\}k-I5
P,*R@N
=0O`VSb
/*Created on 2005-7-15*/ (B[0BjU
package com.adt.service; i8EMjLBUR
wG-X833\(
import net.sf.hibernate.HibernateException; zg "<N
2pZ|+!xc+
import org.flyware.util.page.Page; 6\(\
$Y>LUZ)b&8
import com.adt.bo.Result; 3"cAwU9
yht_*7.lM
/** ;i\i+:=
* @author Joa 9.>v
;:vL
*/ L0Xb^vx}m
publicinterface UserManager { ]G&d`DNV
Vo%@bj~>
public Result listUser(Page page)throws <w8*Ly:L
^e)KEkh
HibernateException; R ]HHbD&;
& [4Gv61
} _g
3hXsA
Un7jzAvQ
MdCEp1Z
:+en8^r%
f%d7?<rw
java代码: 29}(l#S}m
qm8[ ^jO&
\_0nH`
/*Created on 2005-7-15*/ t13wQt
package com.adt.service.impl; ax,%07hJ
^ WidA-
import java.util.List; 0~)cAKus
D1#fy=u69|
import net.sf.hibernate.HibernateException; 1VH7z
O cd
^{u
import org.flyware.util.page.Page; #2/k^N4r
import org.flyware.util.page.PageUtil; epR7p^`7
v2/@Pu!kg
import com.adt.bo.Result; A]QgX5\sa
import com.adt.dao.UserDAO; m)g:@^$
import com.adt.exception.ObjectNotFoundException; ^vfp;
import com.adt.service.UserManager; ?/5WM%
3~%9;.I3!
/** 1s/t}J~zZ
* @author Joa Z!v)zH\
*/ p^MV<}kk
publicclass UserManagerImpl implements UserManager { FK{Vnj0
R~PD[.\u
private UserDAO userDAO; yC(xi"!
Y{6y.F*Q#
/** DTH;d-Z
* @param userDAO The userDAO to set. w<*6pPy
*/ +VCG/J
publicvoid setUserDAO(UserDAO userDAO){ #px74EeI\
this.userDAO = userDAO; OXT 5
y)
} -Uh3A\#(
ewvFUD'j
/* (non-Javadoc) T2Ms/1FH/@
* @see com.adt.service.UserManager#listUser {ZrIA+eH
W0R<^5_
(org.flyware.util.page.Page) ..)O/g.
*/ aHuZzYQ*"j
public Result listUser(Page page)throws bXmX@A$#Io
a=]tqV_
HibernateException, ObjectNotFoundException { N7=lSBm
int totalRecords = userDAO.getUserCount(); ?:H4Xd7
if(totalRecords == 0) e5W 8YNA
throw new ObjectNotFoundException W+k SL{0
#R-l2OO^]
("userNotExist"); A]c'`Nf
page = PageUtil.createPage(page, totalRecords); @FO=0_;y
List users = userDAO.getUserByPage(page); )O;6S$z9Y
returnnew Result(page, users); vtk0 j
} /m"O.17N
`bY>f_5+
} {(Jbgsxm
#Ie/|
aQzx^%B1
BE>^;` K
# 3UrGom
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 n
W:P"L
|KY6IGcqV
询,接下来编写UserDAO的代码: sVWOh|O[W
3. UserDAO 和 UserDAOImpl: _c$l@8KS^
java代码: !8~A`
.FYxVF.
w#0/&\b=
/*Created on 2005-7-15*/ UNY
O
P{
package com.adt.dao; =#L\fe)q)
]L)l5@5^
import java.util.List; uW;[FTcqy$
>oh7f|
import org.flyware.util.page.Page; lrQNl^K}=
?gYQE&M !
import net.sf.hibernate.HibernateException; *62Cf[a
EC;R^)
/** |2AMj0V~
* @author Joa 6,Z.RT{5
*/ Mj!\EUn
publicinterface UserDAO extends BaseDAO { %'o'Kh''=
Y2$wL9">
publicList getUserByName(String name)throws H.o=4[
KJ (|skO
HibernateException; =2XAQiUR\
-,:^dxE'
publicint getUserCount()throws HibernateException; }ZqnsLu[)
b,h@.s
publicList getUserByPage(Page page)throws T&'p5h=l
FT8<a }o
HibernateException; OKi}aQ2R*
y$$|_
l@
} <DR$WsDG
12]rfd
]Xm+-{5?!R
ExKyjWAJ
u0;k_6N
java代码: Nhf@Y}Cu
e92,@
NdxPC~Z+
/*Created on 2005-7-15*/ 6K7DZ96L
package com.adt.dao.impl; unvS `>)Np
>p*7)
import java.util.List; 5FMe &
xyzYY}PS
import org.flyware.util.page.Page; 2p %j@O
zQ~N(Jj?h
import net.sf.hibernate.HibernateException; ~~r7TPq
import net.sf.hibernate.Query; /Z|K9a
+ *)Kyk
import com.adt.dao.UserDAO; xYp-Y"a.
9ERyr1-u v
/** l~Hu#+O
* @author Joa
i"`N5
*/ 3D}Pa
public class UserDAOImpl extends BaseDAOHibernateImpl MX7Y1
=|LB,REN
implements UserDAO { imc1rY!~'
~e<^jhpJ
/* (non-Javadoc) {[pzqzL6
* @see com.adt.dao.UserDAO#getUserByName )k[{re
Xl,707
(java.lang.String) %`bn=~T^
*/ +v+Dkyf:V
publicList getUserByName(String name)throws y$8S+N?>
GLp~SeF#
HibernateException { w,*#z
String querySentence = "FROM user in class z!G?T(SpA
l@:&0id4I
com.adt.po.User WHERE user.name=:name"; j4wsDtmAU
Query query = getSession().createQuery "M3S
A'aY H`j
(querySentence); O03N$Jq
A
query.setParameter("name", name); Nt,:`o |
return query.list(); IOddu2.(
} 0" F\V
ku)/
8Z`$
/* (non-Javadoc) kO/YO)g
* @see com.adt.dao.UserDAO#getUserCount() bfq%.<W
*/ yZ-Ql11
publicint getUserCount()throws HibernateException { >H5_,A}f
int count = 0; }SFmv},Ij
String querySentence = "SELECT count(*) FROM 8b"vXNB.f
':|E$@$W
user in class com.adt.po.User"; ,`!>.E.
Query query = getSession().createQuery \E1CQP-
LEg ?/!LIT
(querySentence); kq*IC&y
count = ((Integer)query.iterate().next weMufT
LJSx~)@
()).intValue(); ]+5Y\~I
return count; l0PXU)>C
} ,&iEn}xG7i
mKJO?7tj
/* (non-Javadoc) QL\3|'a
* @see com.adt.dao.UserDAO#getUserByPage "^)$MAZ
*7{{z%5Pu
(org.flyware.util.page.Page) hAJ^(|
*/ d@?zCFD
publicList getUserByPage(Page page)throws YF(bl1>YC
8dh ?JqX
HibernateException { &,QBJx<#
String querySentence = "FROM user in class gm$<U9L\v
; EsfHCi)
com.adt.po.User"; &`}d;r|yn1
Query query = getSession().createQuery yujv^2/
A
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wm`
(querySentence); %_(^BZd
query.setFirstResult(page.getBeginIndex()) B A
i ^t
.setMaxResults(page.getEveryPage()); J u"/#@
return query.list(); [U,hb1Wi3
} s(:N>K5*
PKZMuEEy,
} -n:;/ere7-
g*WY kv
*|,ye5"
%<>|cO
F6ZL{2$k@
至此,一个完整的分页程序完成。前台的只需要调用 IK,aA;d
/tJ%gF
userManager.listUser(page)即可得到一个Page对象和结果集对象 m0*_
3
jghV?I{T
的综合体,而传入的参数page对象则可以由前台传入,如果用 <Q8d{--o
#iT3aou
webwork,甚至可以直接在配置文件中指定。 }}LjEOvL=
CpU
y~
下面给出一个webwork调用示例: $'w>doUlA
java代码: Yq:+.UU
l]L"Ex{
$ VeQvm*
/*Created on 2005-6-17*/ L;U?s2&Y
package com.adt.action.user; g6H` uO
brdY97s4
import java.util.List; n],"!>=+
7Q|v5@;pU
import org.apache.commons.logging.Log; .X"\ Mg
import org.apache.commons.logging.LogFactory; *>T@3G.{Rm
import org.flyware.util.page.Page; Nkx W*w%}l
;Ouu+#s
import com.adt.bo.Result; D.YT u$T
import com.adt.service.UserService; -yMD9b
import com.opensymphony.xwork.Action; ?^U1~5ff)
Lmc"qFzK
/** |Gt]V`4
* @author Joa 30QQnMH3
*/ 9 j1
tcT
publicclass ListUser implementsAction{ 6~Y`<#X5J
0T:ZWRjH
privatestaticfinal Log logger = LogFactory.getLog vl5r~F
mam(h{f$
(ListUser.class); Ns-3\~QSi
G TW5f
private UserService userService; k&o1z'<C
gP=@u.
private Page page; Gx-tPW}
IJ6&*t
wT
privateList users; mg
*kB:p
#.<(/D+
/* AeEF/*
* (non-Javadoc) bAL!l\&2
* W4=<hB
* @see com.opensymphony.xwork.Action#execute() 7;NvR4P%
*/ (L"G,l
publicString execute()throwsException{ 6}q# c
Result result = userService.listUser(page); $1myf Z
page = result.getPage(); ^qPS&G
users = result.getContent(); Ok_)C+o
return SUCCESS; #zKF/H|_R
} -;U3$[T,J7
3qq6X?y*
/** d<v)ovQJ]
* @return Returns the page. oBzjEv
*/ d+g+{p>?
public Page getPage(){ _"sFLe{
return page; #VM-\02o
} % I;iP|/
/-1 F9
/** 4vf,RjB-5
* @return Returns the users. 8}Su7v1
*/ }P"JP[#E\
publicList getUsers(){ df!n.&\y!
return users; X"
;ly0Mb
} 44_CT?t<
qGKQrb,K
/** FrD,)Ad8Q
* @param page ahm@ +/2
* The page to set. 2~SjRIp Uw
*/ j!QP>AM|`
publicvoid setPage(Page page){ vq*)2.
this.page = page; }_o!fV
} `K\(I#z
H He~OxWg
/** @|J+f5O
* @param users DmgWIede|:
* The users to set. zmh3
Qa(
*/ U)grC8 C
publicvoid setUsers(List users){ *dm?,~f%<
this.users = users; C6(WnO{6
} (eJYv:
^
-4'yC_8t
/** &l NHNu[
* @param userService C!aK5rqhv
* The userService to set. |{H-PH*Iz
*/ >L>t$1hXM
publicvoid setUserService(UserService userService){ e{33%5
this.userService = userService; QH_I<Y:n
} 6s|4'!
} (3+:/,{'$
sz%'=J~!V
Mlr}v^"G
zE\@x+k.
{9C+=v?
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, :]oR x
@q]{s+#Xf
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 T'nQj<dBt:
naoH685R4
么只需要: Qs.g%
java代码: -l`1j6
f*^)0Po
, *A',
<?xml version="1.0"?> *eo<5YUHt
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork wIT}>8o
)Vb_0 n=^
1.0//EN" "http://www.opensymphony.com/xwork/xwork- pC'GKk 8
=D2x@ank[
1.0.dtd"> < l%3P6|
x0!5z1KQh
<xwork> +\a`:QET
)m Uc
!TP
<package name="user" extends="webwork- j7)Xm,wI8
2So7fZa^wg
interceptors"> U ExK|t
dM1)wkbET
<!-- The default interceptor stack name R1DXi
U{2UKD@PM
--> k~st;FO
<default-interceptor-ref ,S i23S\
$MEKt}S
name="myDefaultWebStack"/> 1MCHwX3/
. 787+J?
<action name="listUser" AZCbUkq
@]H:=Q'gj
class="com.adt.action.user.ListUser"> gB\KD{E
<param yjbqby7
`_6!nkq8
name="page.everyPage">10</param> jtk2>Ol
<result &\$l%icuo
/
W}Za&]
name="success">/user/user_list.jsp</result> }7Si2S
</action> 1X4v:rI
#qk A*WP
</package> #`C;@#xr
@t
</xwork>
DdTTWp/
lbv9 kk[
8}0W_C U,
!Q`GA<ikv
J>P{8Aw
n:GK0wu.s
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 I-NzGx2u
PF-7AIxs"
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 4425,AR
i51~/
R
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &P%3'c}G
vv
_I o
1FS Jqad
\k1psqw^O
J(0.eD91v
我写的一个用于分页的类,用了泛型了,hoho h$p]#]uMb
H[guJ)4#@
java代码: v?)-KtX|
)g:\N8AZK
;$G.?r
package com.intokr.util; 9}FWO&LiB
3y%B&W,sm
import java.util.List; c,1Yxg]|
? Ovl(4VG
/** :J-@+_J
* 用于分页的类<br> M* (]hu0!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -y{o@
* d_&R>GmR$
* @version 0.01 /a%5!)NE%
* @author cheng &,xN$
*/ h#?L6<*tm
public class Paginator<E> { Us'm9 J
privateint count = 0; // 总记录数 rS>JzbWa
privateint p = 1; // 页编号 9cAb\5c|
privateint num = 20; // 每页的记录数 ,
e{kC
privateList<E> results = null; // 结果 3~\mP\/4v
\iAkF`OC
/** rLNo7i
* 结果总数 g*b`V{/Vw
*/ ]5lp.#EB
publicint getCount(){ k+2~=#
return count; mvI[=e*
} &AmTXW
"w0>
publicvoid setCount(int count){ }\`MXh's
this.count = count; RF
4u\ \
}
(bi}?V*
@^:R1c![s
/** uh3%}2'P
* 本结果所在的页码,从1开始 G}CzeLw
* \~1M\gZP
* @return Returns the pageNo. w:
~66 TCI
*/ q_5k2'4K
publicint getP(){ 716JnG>
return p; t5#IiPp
} o`HZS|>K*
OS6 l*S('
/** >v @R]9
* if(p<=0) p=1 wxXp(o(
* S1{UVkr
* @param p PD12gUU?
*/ 1FUadSB5)
publicvoid setP(int p){ L5E.`^?
if(p <= 0) ^SB?NRk
p = 1; nnX,_5s
this.p = p; bE.,)GY
} NyI0[]z
j`A%(()d
/** }3F8[Td.~N
* 每页记录数量 FyX\S=
*/ m(E-?VMHo
publicint getNum(){ f(
5c
return num; ps"DL4*
} N;7Xt9l
m5SJB]a/
/** 7.$0LN/a!Z
* if(num<1) num=1 pw*<tXH!
*/ V} Y %9V
publicvoid setNum(int num){ yf+M
if(num < 1) .`&($W
num = 1; V*rAZ0
this.num = num; 1u7Kc'.xc
} "qUUH4mR`
bB'iK4
/** s@K)RhTY
* 获得总页数 C3Q[L}X\
*/ Vo<V!G{
publicint getPageNum(){ BB5(=n+
return(count - 1) / num + 1; .t''(0_kC
} `;4P?!WG
C
Fq3
/** N"/jn_>+j
* 获得本页的开始编号,为 (p-1)*num+1 $Zp\^cIE+
*/ z9pv|
publicint getStart(){ blNJ
return(p - 1) * num + 1; )#zc$D^U
} cS/\&%7u
x2/\%!mt
/** @6 uB78U4O
* @return Returns the results. k'{'6JR
*/ .ml24SeC
publicList<E> getResults(){ %N_5p'W
return results; [ !/u,
} 4%1sOnl
hIu;\dfwk
public void setResults(List<E> results){ N|5J-fR&
this.results = results; H=[eO
} #z_lBg. K
>&3M
#s(w
public String toString(){ 4Ei*\:
StringBuilder buff = new StringBuilder V
@8+
3maiBAOKz
(); ?U.+SQ
buff.append("{"); G#-t&gO3
buff.append("count:").append(count); }Tf~)x
buff.append(",p:").append(p); A@xa$!4}
buff.append(",nump:").append(num); ;`',M6g
buff.append(",results:").append <dl:';@a-
3:Q5dr+1_
(results); 8)HUo?/3
buff.append("}"); UZ7Zzc#g
return buff.toString(); L#mf[a@pCn
} HZC^Q7]hy
[E<NEl*
} =V~pQbZ
6U5L>sQ
RhR{EO