Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 |Pj _L`G
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %hTe%(e
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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 +6;OB@
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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 F(XWnfUv
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分页支持类: R 7{r Y
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java代码: O!j@8~='
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package com.javaeye.common.util; z?gJHN<
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import java.util.List;
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publicclass PaginationSupport { &1?Q]ZRp
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publicfinalstaticint PAGESIZE = 30; 6Edqg
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privateint pageSize = PAGESIZE; '8Gw{&&
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privateList items; H~$|y9>qI
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privateint totalCount; XG[%oL
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privateint[] indexes = newint[0]; R1wdQ8q
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privateint startIndex = 0; +Rh'VZJs
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public PaginationSupport(List items, int $jzk4V
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totalCount){ H{}6`;W
setPageSize(PAGESIZE); ]':C~-RV{
setTotalCount(totalCount); (%r:PcGMEV
setItems(items); u3<])}I'
setStartIndex(0); Z6*RIdD>
} utTek5/
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public PaginationSupport(List items, int r;'!qwr
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totalCount, int startIndex){ j=gbUXv/
setPageSize(PAGESIZE); EP8LJzd"
setTotalCount(totalCount); J\{)qJ*jp
setItems(items); $_ NaxV
setStartIndex(startIndex); D{4
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} <T}#>xHs3
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public PaginationSupport(List items, int #2MwmIeA
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totalCount, int pageSize, int startIndex){ nph{
setPageSize(pageSize); %*/[aq, #
setTotalCount(totalCount); 'v,W
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setItems(items); =DCQ!02
setStartIndex(startIndex); /#
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} Ltj}>.+
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publicList getItems(){ [L\w]6
return items; 0hv[Ff
} Z/I!\
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publicvoid setItems(List items){ 6JL
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this.items = items; |-R::gm
} F+6ZD5/
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publicint getPageSize(){ ZHBwoC#5}
return pageSize; 5 4OYAkPCk
}
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publicvoid setPageSize(int pageSize){ >YW>=5_
this.pageSize = pageSize; -`;8~ wMN
} _+. t7q^
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publicint getTotalCount(){ {NFeX'5bP
return totalCount; y,
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} ::R^ w"
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publicvoid setTotalCount(int totalCount){ jn7}jWA
if(totalCount > 0){ $-y+97
this.totalCount = totalCount; 646yeQ1
int count = totalCount / M&K@><6k,k
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pageSize; <hea%6
if(totalCount % pageSize > 0) CxRp$;rk
count++; WLpn,8qsY
indexes = newint[count]; OBZ |W**N"
for(int i = 0; i < count; i++){ /X:lt^?%I
indexes = pageSize * Vy9n3W"FB1
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i; %,^7J;
} <|8l ;
}else{ }J*&()`
this.totalCount = 0; ^4[\-L8Lpq
} NqWHR~&
} Z:*U/_G
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publicint[] getIndexes(){
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return indexes; lfA
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} ^DH*@M
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publicvoid setIndexes(int[] indexes){ k@~-|\ooG
this.indexes = indexes; B -KOf
} -{wuF0f
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publicint getStartIndex(){ K c<z;
return startIndex; zm:=d>D..
} UVLcR
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publicvoid setStartIndex(int startIndex){ <_>6a7ra
if(totalCount <= 0) /;0>*ft4
this.startIndex = 0; d{he
elseif(startIndex >= totalCount) EH:1Z*|Z{\
this.startIndex = indexes q^cF D
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[indexes.length - 1]; &SM$oy#?
elseif(startIndex < 0) ^M9oTNk2
this.startIndex = 0; P=@lkF!\#
else{ w(U/(C7R
this.startIndex = indexes YfalsQ8
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[startIndex / pageSize]; =4D_-Q
} $P-m6
} +,[3a%c)H
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publicint getNextIndex(){ g#:XN
int nextIndex = getStartIndex() + GW#kaqC1
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pageSize; z]YhQIU4n8
if(nextIndex >= totalCount) ob7_dWAG
return getStartIndex(); u
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else d{hYT\7~1(
return nextIndex; acZHb[w
} 6'ZnyWb
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publicint getPreviousIndex(){ ]*@$%iCPE
int previousIndex = getStartIndex() - !VHIl&Mos
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pageSize; _pGviGR
if(previousIndex < 0) ,OCTm%6e
return0; xdM#>z`;
else =Q}mJs
return previousIndex; h %s
} h6e$$-_
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} r8%,xA&
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抽象业务类 xW9
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java代码: XgKG\C=3
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/** ewG21 q$
* Created on 2005-7-12 \Ji2uGT
*/ :\JbWj_j
package com.javaeye.common.business; ~BZV:Es
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import java.io.Serializable; bW^QH-t
import java.util.List; 3x0wk9lND
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import org.hibernate.Criteria; ->&VbR)
import org.hibernate.HibernateException; ~k0)+D}
import org.hibernate.Session; *F*fH>?C#
import org.hibernate.criterion.DetachedCriteria; 0|!<|N<
import org.hibernate.criterion.Projections; B9DxV>mr\r
import ;cn.s,
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org.springframework.orm.hibernate3.HibernateCallback; }.cmiC
import cu^*x/0,
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org.springframework.orm.hibernate3.support.HibernateDaoS +i#sS19h
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upport; V8$bPVps
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import com.javaeye.common.util.PaginationSupport; ,M&0<k\
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public abstract class AbstractManager extends h&M
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HibernateDaoSupport { F` 5/9?;|
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privateboolean cacheQueries = false; ENWB|@B
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privateString queryCacheRegion; )UZ0gfx
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publicvoid setCacheQueries(boolean d"6]?
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cacheQueries){ 6q[!X0u
this.cacheQueries = cacheQueries; *-AAQ
} eQVPxt2N
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publicvoid setQueryCacheRegion(String )R)$T'
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queryCacheRegion){ 9>&tMq
this.queryCacheRegion = NZC='3Uz
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queryCacheRegion; <S8W~wC
} ^GrkIh0nL
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publicvoid save(finalObject entity){ bjPbl2K
getHibernateTemplate().save(entity); 7{^4 x#NO
} EPe]-C`
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publicvoid persist(finalObject entity){ >6[ X }
getHibernateTemplate().save(entity); @> Ghfh>~D
} $JhZ'Z
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publicvoid update(finalObject entity){ ('**nP
getHibernateTemplate().update(entity); =tc`:!$
} KM5DYy2 A6
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publicvoid delete(finalObject entity){ N+s?ZE*
getHibernateTemplate().delete(entity); 8PoHBOxpc
} [7e{=\`=
fATA%eA8;
publicObject load(finalClass entity, Z6R:
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finalSerializable id){ uspkn1-
return getHibernateTemplate().load y*}vG}e%
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(entity, id); f
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} 3|K=%jr[
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publicObject get(finalClass entity, $m:2&lU3
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finalSerializable id){ :kb1}Wu
return getHibernateTemplate().get sb}K%-
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(entity, id); Z6IJ o%s
} :dY.D|j*
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publicList findAll(finalClass entity){ FQk_#BkK
return getHibernateTemplate().find("from 3?.1~ "-J
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" + entity.getName()); bkr~13S{+
} 0'yG1qG
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publicList findByNamedQuery(finalString Uz6{>OCvk|
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namedQuery){ Rwc[:6;fn
return getHibernateTemplate Q7~'![(a
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().findByNamedQuery(namedQuery); v8=?HUDd
} KInUe(g<9M
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publicList findByNamedQuery(finalString query, k4qLB1&,
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finalObject parameter){ bz,Da
return getHibernateTemplate ,f8}q]FTA
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().findByNamedQuery(query, parameter); S}oG.r
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} "/ tUA\=j
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publicList findByNamedQuery(finalString query, |av*!i5Q
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finalObject[] parameters){ LP.HS'M~u
return getHibernateTemplate
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().findByNamedQuery(query, parameters); U7^7/s/.
} /xl4ohL$a
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publicList find(finalString query){ v6wRME;JA
return getHibernateTemplate().find =nJ{$%L\x,
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(query); =WIE>*3[
} /8f>':zUb
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publicList find(finalString query, finalObject T"n{WmVQ
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parameter){ $aB/+,
return getHibernateTemplate().find h S4.3]ei
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(query, parameter); 0CT}DQ._^N
} 2zz,(RA
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public PaginationSupport findPageByCriteria DW#Bfo
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(final DetachedCriteria detachedCriteria){ 1o8wy_eSs
return findPageByCriteria *D2Nm9sl
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?-pi,O~(p
} ! 0^;;'
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public PaginationSupport findPageByCriteria WP}ixcq#
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(final DetachedCriteria detachedCriteria, finalint tv0Ha A
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startIndex){ ~8TF*3[}[
return findPageByCriteria R~)ybf{
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(detachedCriteria, PaginationSupport.PAGESIZE, 9 CB\n
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startIndex); k0L] R5W
} f-4.WW2FN
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public PaginationSupport findPageByCriteria -ey)J
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(final DetachedCriteria detachedCriteria, finalint )>\4ULR83
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pageSize, 1]T|6N?
finalint startIndex){ ND5$bq Nu?
return(PaginationSupport) ny*i+4Mb
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getHibernateTemplate().execute(new HibernateCallback(){ swcd&~9r
publicObject doInHibernate M4yI`dr6
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(Session session)throws HibernateException { r^fe4b
Criteria criteria = |~0UM$OB^3
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detachedCriteria.getExecutableCriteria(session); 6.WceWBR
int totalCount = 12UD19!
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((Integer) criteria.setProjection(Projections.rowCount qv*7K@
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()).uniqueResult()).intValue(); x;s0j"`Jb
criteria.setProjection UL$}{2N,_
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(null); dT|vYK}\
List items = soRv1) el
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criteria.setFirstResult(startIndex).setMaxResults 4T6 {Y
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(pageSize).list(); o 5U(i
PaginationSupport ps = saf&dd
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new PaginationSupport(items, totalCount, pageSize, "R>FqX6FB
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startIndex); Yr.sm!xA
return ps; j$7|XM6
} O^Q7b7}y
}, true); `F YjQe"p
} i:]*P
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public List findAllByCriteria(final \NZIEu)5?
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DetachedCriteria detachedCriteria){ RGKYW>$0RR
return(List) getHibernateTemplate `.jzuX
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().execute(new HibernateCallback(){ %
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publicObject doInHibernate {9Y+.46S
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(Session session)throws HibernateException { ^hNgm.I
Criteria criteria = XR2~Q)@
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detachedCriteria.getExecutableCriteria(session); M>9-=$7
return criteria.list(); )c n+1R
} LEMfG~Czq
}, true); c0B|F
}
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public int getCountByCriteria(final f=C ,e/sw
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DetachedCriteria detachedCriteria){ 'o|30LzYgQ
Integer count = (Integer) \$0F-=w`8
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getHibernateTemplate().execute(new HibernateCallback(){ +zXEYc
publicObject doInHibernate 2
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(Session session)throws HibernateException { "k]CW\H6z
Criteria criteria = H
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detachedCriteria.getExecutableCriteria(session); ~gB>) ]
return l @^3Exwt
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criteria.setProjection(Projections.rowCount ?A(QyaKz
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()).uniqueResult(); zSo)k~&[3
} t]7&\ihZi~
}, true); $)3%U?AP
return count.intValue(); K>*a*[t0Sy
} ,%\o4Rc'o
} (`y*V;o4
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用户在web层构造查询条件detachedCriteria,和可选的 |V<h=D5W
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 e{m2l2Tx:
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PaginationSupport的实例ps。 R: l&2k@
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ps.getItems()得到已分页好的结果集 DGzw8|/(
ps.getIndexes()得到分页索引的数组 ) $PDo
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ps.getTotalCount()得到总结果数 =i~}84>
ps.getStartIndex()当前分页索引 Mn)@{^
ps.getNextIndex()下一页索引 7b<yVP;{
ps.getPreviousIndex()上一页索引 N^3N[lD{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 hZ.Z3`v70
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 k+ze74_"
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一下代码重构了。 \EVBwE,
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我把原本我的做法也提供出来供大家讨论吧: =5\|[NSK-
3D2E?$dX
首先,为了实现分页查询,我封装了一个Page类: l8?>>.<P=
java代码: 3+XOZh8
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/*Created on 2005-4-14*/ ,v{rCxFtvU
package org.flyware.util.page; l,kUhZ@W
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/** &}A[x1x06)
* @author Joa \_lod kf
* ;cQ6g`
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*/ .FLy;_f+
publicclass Page { bua+I;b
5F~'gLH/F-
/** imply if the page has previous page */ QDu 2?EYZq
privateboolean hasPrePage; 3? HhG
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/** imply if the page has next page */ R00eisd
privateboolean hasNextPage; R=|{n'n$0|
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/** the number of every page */ B#M5}QT|2
privateint everyPage; hC\6-
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/** the total page number */ @~%r5pz6
privateint totalPage; xftBSdVE
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/** the number of current page */ JhLgCnm
privateint currentPage; 8p: j&F
2* 2wY =
/** the begin index of the records by the current *3?'4"B{8
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query */ gy_>`16K
privateint beginIndex; zR{W?_cV
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3h *!V6%q
/** The default constructor */ oIduxbAp
public Page(){ xjVS
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} @9lUSk^9
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/** construct the page by everyPage [_}J F}6
* @param everyPage cj1cZ-
* */ K[!&b0O
public Page(int everyPage){ y$_eCmq
this.everyPage = everyPage; J{k79v
} 5.MGaU^Z$
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/** The whole constructor */ l\@)y4
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public Page(boolean hasPrePage, boolean hasNextPage, (w}H]LQ
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int everyPage, int totalPage, uLWh|
int currentPage, int beginIndex){ R~S;sJ& c
this.hasPrePage = hasPrePage; jW
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this.hasNextPage = hasNextPage; /N&CaH\;^$
this.everyPage = everyPage; 9R7A8
this.totalPage = totalPage; Jz2N
this.currentPage = currentPage; "-+\R}q$
this.beginIndex = beginIndex; 5) pj]S!]-
} A}3=561F?5
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/** 34Kw!
* @return x3o]U)^
* Returns the beginIndex. v#U"pn|M
*/ N _86t
publicint getBeginIndex(){ '*"vkgN
return beginIndex; a
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} C<m{*C-`a
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/** "HDcmIXg&
* @param beginIndex Q|D @Yd\
* The beginIndex to set. *%S"eWb
*/ LC'{p
publicvoid setBeginIndex(int beginIndex){ XYZ4TeW\1
this.beginIndex = beginIndex; @CZT
} NbU [l
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/** Jc|6&
* @return Stu4t==U
* Returns the currentPage. 6{^E{go
*/ 8&)DE@W
publicint getCurrentPage(){ k{Me[B
return currentPage; rjp-Fw~1w
} P8*=Ls+-F
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/** RF%KA[Dj
* @param currentPage ;3B1_vo9
* The currentPage to set. WYEKf9}
*/ TwVlg;
publicvoid setCurrentPage(int currentPage){ j]aoR
this.currentPage = currentPage; a{qM2P(S
} VBcy9|lD
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/** L.jh
* @return /p+>NZ"b
* Returns the everyPage. {:]9Q Tq
*/ 7 D^gMN%p
publicint getEveryPage(){ =p=rg$?
return everyPage; S/ODqL|
} p4-o/8rO
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/** .xH5fMj,"
* @param everyPage ZRg;/sX]
* The everyPage to set. 3P^sM1
*/ 17G'jiYH
publicvoid setEveryPage(int everyPage){ PSZL2iGj9V
this.everyPage = everyPage; #7q7PYG4
} Z^IPZF
f v9V7
/** 4bw4cqY;
* @return 2VE9}%i
* Returns the hasNextPage. cxr=k%~}J
*/ O^^C;U@U<1
publicboolean getHasNextPage(){ 0^RXGN
return hasNextPage; ;bLEL"x%
} }9W4"e 2)
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/** U~j
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* @param hasNextPage twlk-2yT!
* The hasNextPage to set. j"'(sW-
*/ 0iwZT&O
publicvoid setHasNextPage(boolean hasNextPage){ oze&
this.hasNextPage = hasNextPage; #[`:'e
} }0X:F`Y-
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/** GP:77)b5
* @return < !dqTJos
* Returns the hasPrePage. eK!V
);
*/ 1PP $XJtyD
publicboolean getHasPrePage(){ 0Pe>Es|^A#
return hasPrePage; 52,m:EhL
} (Yis:%c\!
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/** MvWaB
* @param hasPrePage j(k:
@
* The hasPrePage to set. Y5FbU
*/ D? 8rO"
publicvoid setHasPrePage(boolean hasPrePage){ AG?dGj^
this.hasPrePage = hasPrePage; uec!RKE
} j"|=C$Kn/
m$W <
/** j;fpQ_KL
* @return Returns the totalPage. PUBWZ^63
* 846$x$G4
*/ Qe}`~a9P
publicint getTotalPage(){ J<dVTxK12
return totalPage; :h&fbBH
} WeQk<y
?$6Y2
/** },>pDeX^P
* @param totalPage C~N/A73gF
* The totalPage to set. Eg2[k.{P
*/ bV$)!]V
publicvoid setTotalPage(int totalPage){ D[mSmpjE6&
this.totalPage = totalPage; LjUy*mxw
} 1I<rXY(a`
nZ@&2YPlem
} w[!^;#
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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 =}v}my3y"
j|/]#@Yr
个PageUtil,负责对Page对象进行构造: i 4%xfN
java代码: DV\`Wv
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/*Created on 2005-4-14*/ kRTwaNDOD
package org.flyware.util.page; @H7Wb}
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import org.apache.commons.logging.Log; }*ZHgf]~#
import org.apache.commons.logging.LogFactory; 5fm?Lxr&?
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/** (q4),y<:[
* @author Joa eOXHQjuj
* C!R1})_^
*/ +[R/=$
publicclass PageUtil { *+\SyO
7G\\{
privatestaticfinal Log logger = LogFactory.getLog 't_[dSO
` bdZ/*E
(PageUtil.class); |R56ho5C
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/** 1xbK'i:-S
* Use the origin page to create a new page Ci<ATho
* @param page rDQ!zlg>l
* @param totalRecords 8S<@"v
* @return |{@8m9JR
*/ _x?uU
publicstatic Page createPage(Page page, int x,otFp
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totalRecords){ }j^\(2
return createPage(page.getEveryPage(), FP>)&3>_
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page.getCurrentPage(), totalRecords); ?@6/E<-Z$
} Vg>( Y,
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/** xritonG/F
* the basic page utils not including exception GN0`rEh
[ e8x&{L-_
handler svuq gSn
* @param everyPage GQl$yZaK{
* @param currentPage $ KRI'4
* @param totalRecords %<\6TZr
* @return page +Ag!?T
*/ 7As|Ns`
publicstatic Page createPage(int everyPage, int PNA\ TXT
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currentPage, int totalRecords){ qt3PXqR7:
everyPage = getEveryPage(everyPage); ^m/oDB-
currentPage = getCurrentPage(currentPage); A^RR@D
int beginIndex = getBeginIndex(everyPage, #!$GH_
A)~X,
currentPage); qBQ`~4s
int totalPage = getTotalPage(everyPage, tBm_YP[
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totalRecords); Hzhceeh_+
boolean hasNextPage = hasNextPage(currentPage, e+]6OV&+
m "M("%
totalPage); M#4QQ} F.
boolean hasPrePage = hasPrePage(currentPage); 0UH*\<R
"
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returnnew Page(hasPrePage, hasNextPage, +R\vgE68
everyPage, totalPage, nD0}wiL{
currentPage, %\kOLE2`
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beginIndex); DEw8*MN
} #9m$ N
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privatestaticint getEveryPage(int everyPage){ cDoo*
return everyPage == 0 ? 10 : everyPage; `g_"GE
} #k$)i[aI-
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privatestaticint getCurrentPage(int currentPage){ r,]#b[:.s|
return currentPage == 0 ? 1 : currentPage; a2f^x@0k
} N6T{
rFZrYm
privatestaticint getBeginIndex(int everyPage, int \NGC$p n
5PIZh<
currentPage){ yE\wj
return(currentPage - 1) * everyPage; IF +i3#$
} KZbR3mi,
?,=f\Fz!
privatestaticint getTotalPage(int everyPage, int "0EA;S8$8
8*SP~q
totalRecords){ ~RBrSu)
int totalPage = 0; IhiGP
{
@[6,6:h|
if(totalRecords % everyPage == 0) aZk&`Jpz
totalPage = totalRecords / everyPage; \@~UDP]7
else !'f3>W\
totalPage = totalRecords / everyPage + 1 ; o]LRzI
/EMJSr
return totalPage; 1mSaS4!"B
} 5y}
v{Ijt
!$g+F(:(c
privatestaticboolean hasPrePage(int currentPage){ 0fs$#j
return currentPage == 1 ? false : true; >qo~d?+
} &48_2Q"{
rxO2js
privatestaticboolean hasNextPage(int currentPage, UkfB^hA
_0pO8o-x
int totalPage){ y\F=ui
return currentPage == totalPage || totalPage == ;U`X 6d
+jqj6O@Tjr
0 ? false : true; .9|uQEL
} ]bgY6@M
#*c F8NV-
-Z^4L
} 1j\aH&)GH
=/+#PVO
~"!a9GZ
{6d b{ ay_
-Y:ROoFOZ
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。 !7U\J]
^ie^VY($
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 5M23/=
N
m_!U}!
做法如下: *mBJ?{ !
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 l9/:FiJ_
\h3e-)
的信息,和一个结果集List: Gqyue7;0,
java代码: mEQ!-p
m]IysyFFK
\,sg)^w@
/*Created on 2005-6-13*/ _a+ICqR
package com.adt.bo; ex?\c"
c-5jYwV
import java.util.List; E/za@W
1]\TI7/n
import org.flyware.util.page.Page; b0a}ME&1
L8V3BH7B
/** ?Ay3u^X
* @author Joa (Q-I8Y8l8
*/ qi+&|80T.
publicclass Result { Cj&$%sO1
vZajT!h
private Page page;
'H FK Bp
j[P8
private List content; (G4'(6
b4 hIeBI\
/** W>L@j(
* The default constructor Q-zdJt
*/ l_v*7d
public Result(){ 1.SkIu%
super(); H/+{e,SW"
} wq4nMY:#
'1]7zWbW
/** ;IC'Gq
* The constructor using fields KtTza5aF
* HR3_@^<7
* @param page <4zT;:NQ
* @param content [F|+(}
*/ <{019Oa
public Result(Page page, List content){ fQQ|gwVki
this.page = page;
q{X T
this.content = content; V_;9TC
} `)[dVfxA
abZdGnc
/** (5;D7zdA
* @return Returns the content. /84bv=
*/ <pOl[5v]
publicList getContent(){ *fP(6e#G,
return content; >QI~`MiI
} PV,"-Nv,
JIUtj7HQ
/** ~tNY"{OV#
* @return Returns the page.
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+0
*/ n(jjvLf
public Page getPage(){ TmiWjQv`
return page; "2mFC!
} Ky&KF0
S+FQa7k
/** +t>XxYScx
* @param content 2cjEex:&
* The content to set. Za!w#j%h
*/ +Pw,Nl\KD
public void setContent(List content){ J v<$*TVS0
this.content = content; !BRcq~-.
} @xJCn}`Zj
m;h<"]<
/** <9\,QR)
* @param page aQmfrx
* The page to set. hb! ln7
*/ E{gv,cUM
publicvoid setPage(Page page){ .b _? -Fv
this.page = page; -gSj>b7T
} p1
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} vpa fru4
i>"dBJh]b
v?%3~XoH
.M+v?Ad
&Y=.D:z<
2. 编写业务逻辑接口,并实现它(UserManager, 3`rIV*&_{
eKJ:?Lxv;
UserManagerImpl) M,JA;a, _
java代码: &gWiu9WbS
<N5rv3
s
hBoP=X.~
/*Created on 2005-7-15*/ 1$OVe4H1
package com.adt.service; "<*nZ~nE)
8;8YA1@w
import net.sf.hibernate.HibernateException; {,F/KL^u
+',^((o
import org.flyware.util.page.Page; `x4E;Wjv
|1i]L @&
import com.adt.bo.Result; |>@-grs
mo*'"/
/** `+^sW#ki
* @author Joa 4
iKR{P6
*/ @% H8"A
publicinterface UserManager { 5&G
5eA
TC@bL<1
public Result listUser(Page page)throws 0T1ko,C!,e
*) }
:l
HibernateException; bHJoEYY^
m8u=u4z("
} L^jaBl
Dh?vU~v(6
W[GQ[h
_^b@>C>O
+]_nbWL(%
java代码: u x#.:C|
[NZ-WU&&LP
WzlS^bZ
/*Created on 2005-7-15*/ -^Rb7 g-
package com.adt.service.impl; iz$FcA]
+
lP5XY{
import java.util.List; *0-v!\{
[5!'ykZ
import net.sf.hibernate.HibernateException; Kny%QBoiw
fZ{&dslg
import org.flyware.util.page.Page; p6 <}3m$
import org.flyware.util.page.PageUtil; /_HwifRQ
&:q[-K@!
import com.adt.bo.Result; }ymc5-
import com.adt.dao.UserDAO; ;fj9n-
import com.adt.exception.ObjectNotFoundException;
rWqkdi1
import com.adt.service.UserManager; %P(;8sS
Kc-Y
/** Gxo#
!
* @author Joa n+X1AOE[L
*/
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publicclass UserManagerImpl implements UserManager { ?LR"hZ>
6 1L7
-~
private UserDAO userDAO; Ogd8!'\
;C+cE#
/** e/ WBgiLw
* @param userDAO The userDAO to set. U|9U(il
*/ [4ee <J
publicvoid setUserDAO(UserDAO userDAO){ *$JB`=Q
this.userDAO = userDAO; D7M0NEY
} ^t`f1rGR
)&XnM69~b
/* (non-Javadoc) q%DVDq( z
* @see com.adt.service.UserManager#listUser Q5hb0O%a
0n\^$WY
(org.flyware.util.page.Page) w[e0wh`.
*/ >/8ru*Oc
public Result listUser(Page page)throws I'xC+nL@
R04.K!
HibernateException, ObjectNotFoundException { c1PViko,>
int totalRecords = userDAO.getUserCount(); XynU/Go,
if(totalRecords == 0) Zo'/^S
throw new ObjectNotFoundException ;x,+*%
)-)ss"\+Ju
("userNotExist"); Fgskb"k/
page = PageUtil.createPage(page, totalRecords); g&q]@m
List users = userDAO.getUserByPage(page); k?o^5@b/
returnnew Result(page, users); 2ve
lH;
} V;H
d)v(j
_k6x=V;9g
} DakLD~H;
p}96uaC1
N&?T0Ge;
%A8Pkr<&E
-QN1oK@\mE
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 BXNI(7xi
FwXKRZa
询,接下来编写UserDAO的代码: Q@7l"8#[t
3. UserDAO 和 UserDAOImpl: nt drXg
java代码: ,tcP=fdk]
"3\oQvi.
|
A3U@>6
/*Created on 2005-7-15*/ (W7;}g ysh
package com.adt.dao; i5.?g <.H
eVZa6la"
import java.util.List; .4H_Zt[2
f3/SO+Me}
import org.flyware.util.page.Page; &t~zD4u B
<9ePi9D(
import net.sf.hibernate.HibernateException; Sjw2 j#Q
1RCXc>}/
/** lr-12-D%-
* @author Joa 2T//%ys=
*/ AQB1gzE
publicinterface UserDAO extends BaseDAO { ?@3#c
/&*m1EN#o
publicList getUserByName(String name)throws v&p,Clt-2
kw6cFz
HibernateException; j#7wyi5q
zt-'SY
publicint getUserCount()throws HibernateException; 9 %D$T'K
f-vZ2+HP
publicList getUserByPage(Page page)throws u+I3IdU3
wy,Jw3
HibernateException; wCV>F-
#L_@s
d
} NS7@8 #C
AF6d#Klog
dNOX&$/=
A
Z4|&iT
BO?mQu~
java代码: -
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8FB\0LA!g
nw~/~eM5=
/*Created on 2005-7-15*/ ;%BhhmR)[
package com.adt.dao.impl; ~!8%_J _
n^* >a
import java.util.List; @*CAn(@#N
A)hq0FPp
import org.flyware.util.page.Page; xIS\4]F?r
gV<0Hj
import net.sf.hibernate.HibernateException; ]]\)=F`n77
import net.sf.hibernate.Query; .tZjdNE(h
cYZwWMzp
import com.adt.dao.UserDAO; wrz+2EP`
\Ku9"x
/**
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* @author Joa M3DxapG
*/ ?l6>6a7
public class UserDAOImpl extends BaseDAOHibernateImpl C>.]Bvg
Py|H?
, 6=
implements UserDAO { i0,%}{`
>v^2^$^u
/* (non-Javadoc) Am>_4
* @see com.adt.dao.UserDAO#getUserByName s$f+/Hs
>E//pr)_Km
(java.lang.String) zkjPLeX
*/ hknwis%y
publicList getUserByName(String name)throws fl} rz
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HibernateException { "2)+)Db
String querySentence = "FROM user in class :'5G_4y)h
=giM@MV
com.adt.po.User WHERE user.name=:name"; /Oq1q._9F
Query query = getSession().createQuery hg[l{)Q
1$:{{%
(querySentence); =?meO0]y
query.setParameter("name", name); j#*asGdp#J
return query.list(); 9F2P(aS
} w o-O_uZB
pieU|?fQ
/* (non-Javadoc) :)KTZ
* @see com.adt.dao.UserDAO#getUserCount() fOqS|1rC
*/ L
LYHr
publicint getUserCount()throws HibernateException { Ov$N"
int count = 0; B6tcKh9d,
String querySentence = "SELECT count(*) FROM S[W9G)KWp
LP5eFl`|T
user in class com.adt.po.User"; ^ 4u3Q
Query query = getSession().createQuery m&Y;/kr
8CHb~m@^$
(querySentence); .nj?;).
count = ((Integer)query.iterate().next Rz<d%C;R
A2g"=x[1@K
()).intValue(); }XfS#Xr1aV
return count;
o9U0kI=W
} GNhtnB
6MLN>)t
/* (non-Javadoc) 6.
+[
z
* @see com.adt.dao.UserDAO#getUserByPage 2+T 8Y,g
n:5O9,umZ
(org.flyware.util.page.Page) ]C}u-B746
*/ HI"!n$p
publicList getUserByPage(Page page)throws 2x<Qt2"
BiHiVhD_
HibernateException { &=s|
String querySentence = "FROM user in class 6e$sA (a=i
9B!im\]O
com.adt.po.User"; 4i+PiD:H
Query query = getSession().createQuery % +kT
37:b D
(querySentence); .LXh]I*
query.setFirstResult(page.getBeginIndex()) '(3Nopl
.setMaxResults(page.getEveryPage()); EzD
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return query.list(); >gX0Ij#G
} nZ`2Z7!
[a>JG8[,t
} |xsV(jK8
877EKvsiC
q
G :jnl
j=xtnIq
@\%)'WU
至此,一个完整的分页程序完成。前台的只需要调用 3PvZ_!G
P`Hd*xh".j
userManager.listUser(page)即可得到一个Page对象和结果集对象 _V_8p)%
a'_MhJ zs
的综合体,而传入的参数page对象则可以由前台传入,如果用 \p>]G[g
Y^c,mK^
webwork,甚至可以直接在配置文件中指定。 X] JpS
C0t+Q
下面给出一个webwork调用示例: ,E*a$cCw
java代码: ?RRSrr1
e6{[o@aM{
\J,- <wF
/*Created on 2005-6-17*/ @n~>j&Kp
package com.adt.action.user; (PsSE:r}+
=BqaGXr
import java.util.List; 5I8FD".i
[x$eF~Kp
import org.apache.commons.logging.Log; -CU7u=*b
import org.apache.commons.logging.LogFactory; A]tf>H#1
import org.flyware.util.page.Page; I9:G9
>?G|Yz*kEJ
import com.adt.bo.Result; F653[[eQ
import com.adt.service.UserService; N#pl mPrZ
import com.opensymphony.xwork.Action; PxP?hk
rx}ujjx
/** N1s$3Ul
* @author Joa \4\\575zp'
*/ c5B_WqjJ
publicclass ListUser implementsAction{ 7/^TwNsv
~q8V<@?
privatestaticfinal Log logger = LogFactory.getLog Zv1Bju*y
7'{Yz
(ListUser.class); r'9=kx
Y6;0khp
private UserService userService; =XacG}_
~x0-iBF
private Page page; U>L=.\\|
Zeme`/aBb
privateList users; PBAz`y2
YL9t3]
/* Lilk8|?#W
* (non-Javadoc) oxCs*
* ~7ATt8T
* @see com.opensymphony.xwork.Action#execute() VHgF#6'
*/ K)h"G#NZM
publicString execute()throwsException{ I7G\X#,iz
Result result = userService.listUser(page); j;AzkReb
page = result.getPage(); <D;H}ef
users = result.getContent(); nIT ^'
return SUCCESS; *xv/b=
} XC$+ `?
3h D2C'KD
/** &aevR^f+
* @return Returns the page. 1VjeP
*
*/ "#\bQf}
public Page getPage(){ +}(B856+
return page; $^NWzc
} WfTdD.Xx
uG(~m_7Hx
/** ,s yA()
* @return Returns the users. j6R{
*/ 3|83Jnh
publicList getUsers(){ t0asW5f
return users; 2LxVt@_R!%
} OuBMVn
eX
l%Qs#Y
/** zW"3K
* @param page j3rv2W\
* The page to set. -EkDG]my
*/ u6qi
publicvoid setPage(Page page){ #H|j-RM2
this.page = page; r;%zGF p
} /[0 /8f6
u'~b<@wHB
/** >uPde5"ZF-
* @param users J%Z)#
* The users to set. y`B!6p
5j
*/ VI|DMx
publicvoid setUsers(List users){ $p6Xa;j$ 9
this.users = users; 2p3u6\y
} q|
=q:4_L
|Z7bd^
/** t~<-4N$(
* @param userService oVEr {K)
* The userService to set. ,5<`+w#a
*/ 2GD mZl
publicvoid setUserService(UserService userService){ L$u&~"z-
this.userService = userService; 602eLV)
} {ZsWZJ!
} 8F\Msx
3R=3\;
|L_g/e1 A3
cdtzf:#q
HyX4ob[X
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, _@~kYz
[;CqvD<S
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 }PIGj} F/
9}qfdbI
么只需要: ik:)-GV;s
java代码: }rMpp[
G4exk5
Znl>*e/|
<?xml version="1.0"?> q=0{E0@9({
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork xZ'`_x9l
.vOpU4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- |b'<XQ&l5
k89gJ5B$
1.0.dtd"> (+Kof
'3_B1iAv
<xwork> =
a.n`3`Q
v!RB(T3
<package name="user" extends="webwork- zju,#%
zR JKIm
interceptors"> *~<]|H5~
|e-+xX|;
<!-- The default interceptor stack name K9N0kBJ0<
4FHX#`
--> z.9FDQLp
<default-interceptor-ref GwpBDMk
g d}TTe
name="myDefaultWebStack"/> ]Y:
W[p
%K7EF_%
<action name="listUser" v/00LR
X3=Jp'p$h
class="com.adt.action.user.ListUser"> Lz>{FOR
<param rNzhP*Fw
CT:eV7<>s
name="page.everyPage">10</param> KjfKo;T
<result H"RF[bX(
`:BQ&T%UQR
name="success">/user/user_list.jsp</result> L"du"-
</action> ; 7v7V
;YXr G
</package> {6y.%ysU
Q.E^9giC
</xwork> =jv$ 1
sd@gEp)L
H-
qP>:
HYYx*CJ)
79B`w
#
|`;1p@w"
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 ^sn>p}Tg
"`gZy)E
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。 *0@;
kD=
V45Udwp^
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 yY-t4WeXP
=qR7-Q8B
DHNii_w4v
lGHu@(n<
{ugKv?e;
我写的一个用于分页的类,用了泛型了,hoho *9{Wn7pck/
%TTL^@1!b
java代码: {*Wwu
f.
)I-?zyL
pW^ ?g|_}
package com.intokr.util; Y*`A$
I4X+'fW,
import java.util.List; G@<lwnvD*J
\C2P{q/m
/** {,C8}8a W
* 用于分页的类<br> %ih7Jt
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #`)-$vUv^f
* hRZS6" #
* @version 0.01 j{-7Pf8A
* @author cheng ;OCI.S8
*/ Odjd`DD1
public class Paginator<E> { Bsk2&17z
privateint count = 0; // 总记录数 RTA=|q
privateint p = 1; // 页编号 qg:I+"u
privateint num = 20; // 每页的记录数 xI\s9_"Qy
privateList<E> results = null; // 结果 Y^m=_*1g5
n*4X/K
/** ;)pV[3[
* 结果总数 U\ E{-7
*/ >A( C9_\
publicint getCount(){ C2|2XL'l(C
return count; Xg3[v3m|
} $AhX@|?z
4m(>" dHP
publicvoid setCount(int count){ -R
\@W q@
this.count = count; k3.p@8@:
} $M<