Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _/F}y[B7d
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 <}AmzeHr+
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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 ypY7uYO^"
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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 fXAD~7T*s
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分页支持类: UG,n
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java代码: TK#-;p_
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package com.javaeye.common.util; &0J/V>k
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import java.util.List; fq0[7Yb
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publicclass PaginationSupport { lziC.Dpa
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publicfinalstaticint PAGESIZE = 30; 2Zw]Uu`sb
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privateint pageSize = PAGESIZE; Jry643K>:;
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privateList items; ,CnUQx0
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privateint totalCount; \J^xpR_0u
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privateint[] indexes = newint[0]; 20mZ{_%
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privateint startIndex = 0; qAuq2pHA+d
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public PaginationSupport(List items, int )"y]_}
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totalCount){ A*3R@G*h
setPageSize(PAGESIZE);
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setTotalCount(totalCount); Rj,M|9Y)o
setItems(items); r7N%onx
setStartIndex(0); 7>|p_o`e
} bl;v^HR0)
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public PaginationSupport(List items, int JPS<e*5
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totalCount, int startIndex){ |-VbJd
setPageSize(PAGESIZE); *wJ'Z4_5F
setTotalCount(totalCount); |c!lZo/
setItems(items); 7.xJ:r|
setStartIndex(startIndex); Px"K5c*
} pXHeUBY.
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public PaginationSupport(List items, int " qrL:,
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totalCount, int pageSize, int startIndex){ aV?r %'~Z
setPageSize(pageSize); BGVy
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setTotalCount(totalCount); QjwCY=PK!
setItems(items); {m<!-B95
setStartIndex(startIndex); @GE:<'_:{
} cOEzS
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publicList getItems(){ U>_#,j
return items; WnC0T5S?U
} GE.@*W
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publicvoid setItems(List items){ Voc&T+A m
this.items = items; 9TW
} TVFxEV7Fx
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publicint getPageSize(){ ;= {Z Bx
return pageSize; WWYG>C[
} 9<I;9.1S?^
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publicvoid setPageSize(int pageSize){ Fgg4QF
this.pageSize = pageSize; _d/ZaCx'i
} Mt`XHXTp
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publicint getTotalCount(){ quw:4W>
return totalCount; Li\BRlebR{
} 1_.#'U>
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publicvoid setTotalCount(int totalCount){ B 9AE*
if(totalCount > 0){ Sf0[^"7
this.totalCount = totalCount; [u2)kH$
int count = totalCount / "t"&6\
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pageSize; H@WQO]PA
if(totalCount % pageSize > 0) QabYkL5@
count++; abM4G
indexes = newint[count]; XD\Z$\UJE
for(int i = 0; i < count; i++){ CDM==Xa*
indexes = pageSize * \M`fkR,,'
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i; 1)m&6:!b
} 7oI^sh k
}else{ OT5'c l
this.totalCount = 0; BV
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} g8_IZ(%:
} &vp0zYd+v
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publicint[] getIndexes(){ 9#@CmiIhy
return indexes; vXM``|
} 3M&75OE
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publicvoid setIndexes(int[] indexes){ 2=l!b/m
this.indexes = indexes; oxPb; %
} W=~H_L?/
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publicint getStartIndex(){ +2ih!$T;7>
return startIndex;
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} O}3M+
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publicvoid setStartIndex(int startIndex){ OAQ'/{~7
if(totalCount <= 0) {L8(5
this.startIndex = 0; vv,(ta@t2
elseif(startIndex >= totalCount) }`9}Q
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this.startIndex = indexes r8~U@$BBK
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[indexes.length - 1]; {9Op{bZ
elseif(startIndex < 0) G{ $Zg
this.startIndex = 0; %R{clbbbn
else{ ]X)EO49
this.startIndex = indexes ^$y_~z3o#7
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[startIndex / pageSize]; s"?&`S
}
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} IczEddt@'
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publicint getNextIndex(){ ;G3{ e
int nextIndex = getStartIndex() + `v)-v<
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pageSize; | JL47FR
if(nextIndex >= totalCount) ]eq3cwR[|
return getStartIndex(); -~h2^Oez
else 6X:-Z3
return nextIndex; #|8!0]n'
} O ,[aL;v
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publicint getPreviousIndex(){ n.y72-&v
int previousIndex = getStartIndex() - ";e0-t6:
$sO}l
pageSize; 7j&l2Z
if(previousIndex < 0) >}/"gx
return0; +*
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else 8X]j;Rb
return previousIndex; }h>e=<
} w|PZSOJ
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} l(zkMR$b8
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抽象业务类 DRVvW6s
java代码: _ #l b\
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/** #
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* Created on 2005-7-12 +.HQ+`8z]
*/ m=fmf(
package com.javaeye.common.business; jt2m-*aP
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import java.io.Serializable; hv
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import java.util.List; !HDk]
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import org.hibernate.Criteria; Qq]UEI `Go
import org.hibernate.HibernateException; '7'cKp
import org.hibernate.Session; ^ I,1kl~i
import org.hibernate.criterion.DetachedCriteria; &TWO/F+Y
import org.hibernate.criterion.Projections; 5
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import XW]|Mv[M
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org.springframework.orm.hibernate3.HibernateCallback; Yjk A^e
import 60AX2-sdJ,
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org.springframework.orm.hibernate3.support.HibernateDaoS #>ci!4Gz=Z
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upport; ^"+cJ)
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import com.javaeye.common.util.PaginationSupport; rT}d<cSf
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public abstract class AbstractManager extends (DKpJCx
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HibernateDaoSupport { on&N=TN
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privateboolean cacheQueries = false; Z{_'V+Q1
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privateString queryCacheRegion; ,%nmCetD@
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publicvoid setCacheQueries(boolean "TjR]jnV(
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cacheQueries){ 3y 3
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this.cacheQueries = cacheQueries; 3+ i(fg_
} Z/x<U.B
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publicvoid setQueryCacheRegion(String xI:;%5{LN
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queryCacheRegion){ 4N` MY8',
this.queryCacheRegion = #2HygS
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queryCacheRegion; 29Q5s$YD@
} [sNn^x
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publicvoid save(finalObject entity){ }.b[a z\T
getHibernateTemplate().save(entity); J;T_9
} q9WSQ$:z8
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publicvoid persist(finalObject entity){ &
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getHibernateTemplate().save(entity); Va*Uwy?x/)
} s9[v_(W
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publicvoid update(finalObject entity){ dqKTF_+VhA
getHibernateTemplate().update(entity); bh7 1Zu
} DD3J2J
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publicvoid delete(finalObject entity){ KP<J~+_ik
getHibernateTemplate().delete(entity); ^jmnE.8R
} /
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publicObject load(finalClass entity, Fsq S)
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finalSerializable id){ ]-PF? 8
return getHibernateTemplate().load 1@nR.v"$
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(entity, id); RXWjFv~/
} e&0B4wVAQ
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publicObject get(finalClass entity, y6PAXvv'{
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finalSerializable id){ dU&.gFw1
return getHibernateTemplate().get >$Fc=~;Ba
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(entity, id); #!`zU4&2
} IYCKF/2o
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publicList findAll(finalClass entity){ R<U?)8g,h~
return getHibernateTemplate().find("from zA"D0fr
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" + entity.getName()); k Lv_P[I
} f`IgfJN
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publicList findByNamedQuery(finalString !<YRocQY
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namedQuery){ BO9Z"|"
return getHibernateTemplate Zi[)(agAT
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().findByNamedQuery(namedQuery); Iiy:<c
} ynDx'Q* N'
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publicList findByNamedQuery(finalString query, pz$$K?
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finalObject parameter){ v;RQVH;,
return getHibernateTemplate KqS2
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().findByNamedQuery(query, parameter); +I Ze`M%n
} ~.@fk}'R
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publicList findByNamedQuery(finalString query, Z956S$gS
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finalObject[] parameters){ iZSSd{jO
return getHibernateTemplate XsG]-Cw
Cir =(
().findByNamedQuery(query, parameters); Ov<3?)ok
} xLD6A5n,[
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publicList find(finalString query){ ,X$Avdc2
return getHibernateTemplate().find 6Ss{+MF|v
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(query); {//F>5~[
} 8uGPyH
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publicList find(finalString query, finalObject LNN:GD)>
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parameter){ f C^l9CRY
return getHibernateTemplate().find pS<b|wu?f
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(query, parameter); NF1D8uI
} GVfu_z?
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public PaginationSupport findPageByCriteria dH/t|.%
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(final DetachedCriteria detachedCriteria){ 1`}fbX;"m)
return findPageByCriteria )4`Ml*7x
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); y="SzPl
} V%0.%/<#5
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public PaginationSupport findPageByCriteria nM; G;
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(final DetachedCriteria detachedCriteria, finalint nfJ8Rt
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startIndex){ *M|\B|A.
return findPageByCriteria ~4>Xi*
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(detachedCriteria, PaginationSupport.PAGESIZE, V-cuG.
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>
startIndex); @\DD|o67
} kdUGmR0d
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public PaginationSupport findPageByCriteria > 4ct[fW+
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(final DetachedCriteria detachedCriteria, finalint Me}TW!GC
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pageSize, \i,cL)HM
finalint startIndex){ rq1kj 8%2
return(PaginationSupport) %)/f; T6
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getHibernateTemplate().execute(new HibernateCallback(){ Hr+-ndH!Pq
publicObject doInHibernate VBX#
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(Session session)throws HibernateException { [[e |GQ
Criteria criteria = 3opLLf_g
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detachedCriteria.getExecutableCriteria(session); //
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int totalCount = 4v|/+J6G
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((Integer) criteria.setProjection(Projections.rowCount I:e2sE
":
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()).uniqueResult()).intValue(); ?:?4rIZ<
criteria.setProjection @"I#b99
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(null); ' 4~5ez|:
List items = H< ;Fb;b
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criteria.setFirstResult(startIndex).setMaxResults f^)uK+:.
+2zuIW.
(pageSize).list(); Ib2 @Wi
PaginationSupport ps = 9 <KtI7
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new PaginationSupport(items, totalCount, pageSize, &Bn; Vi
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startIndex); lk +K+Ra/
return ps; DVhTb
} \B2d(=~4
}, true); ,z1!~gIal
} 7I(t,AKJ
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public List findAllByCriteria(final aE BP9RX}z
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DetachedCriteria detachedCriteria){ ,0Zn hS)kq
return(List) getHibernateTemplate %EGr0R(
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().execute(new HibernateCallback(){ B/=q_.1F>
publicObject doInHibernate x~;EH6$5'/
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(Session session)throws HibernateException { /Tj"Fl\h
Criteria criteria = !/}FPM_
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detachedCriteria.getExecutableCriteria(session); e(#IewKp
return criteria.list(); ?4ILl>*
} B#aH\$_U
}, true); h_~|O[5|)
} R*@[Pg*
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public int getCountByCriteria(final EB>B,#
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DetachedCriteria detachedCriteria){ L)lQ&z?
Integer count = (Integer) }[z<iij4
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getHibernateTemplate().execute(new HibernateCallback(){ )_v\{N
publicObject doInHibernate )@qup _M@
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(Session session)throws HibernateException { P=^#%7J/l
Criteria criteria = QP%kL*=8
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detachedCriteria.getExecutableCriteria(session); "Py Wo
return @%<?GNS O
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criteria.setProjection(Projections.rowCount X
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()).uniqueResult(); 4C1FPrh
} k=7Gr;;l=p
}, true); C,r`I/;
return count.intValue(); h4anr7g{
} EF=dXm/\
} NGD*ce"w
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用户在web层构造查询条件detachedCriteria,和可选的 *v
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 fYhR#FVI
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PaginationSupport的实例ps。 ,?k%jcR
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ps.getItems()得到已分页好的结果集 Ud#X@xK<h
ps.getIndexes()得到分页索引的数组 T^$g N|
ps.getTotalCount()得到总结果数 <jUrE[x
ps.getStartIndex()当前分页索引 P>Q{He:
ps.getNextIndex()下一页索引 %l}Q?Z
ps.getPreviousIndex()上一页索引 0)AM-/"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 IyS"
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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 yW\XNX
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一下代码重构了。 rLJ[FqS
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我把原本我的做法也提供出来供大家讨论吧:
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hCM8/Vvx6
首先,为了实现分页查询,我封装了一个Page类: CE#\Roi x)
java代码: cJ(BiL-uF
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/*Created on 2005-4-14*/ 8xF)_UV
package org.flyware.util.page; qL|
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/** H`m:X,6}
* @author Joa oYz!O]j;a
* #JA}LA"l
*/ U:]MgZWn
publicclass Page { AkrTfi4hC
ZXsYn
/** imply if the page has previous page */ QsF4Dl
privateboolean hasPrePage; dhHEE|vrz
s`hav
/** imply if the page has next page */ J&eAL3"GF
privateboolean hasNextPage; $!G` D=
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/** the number of every page */ 47IY|Jdz
privateint everyPage; r6`\d k
m0A# 6=<
/** the total page number */ i&`!|X-=R
privateint totalPage; fVe@YqNa
I%@e@Dm,h
/** the number of current page */ XRa(sXA3
privateint currentPage; ]gu1#
$$JIBf8
/** the begin index of the records by the current ll^DY
hx}
XHxz @_rw
query */ 90~*dNk
privateint beginIndex; ~,ynJ]_aJB
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/** The default constructor */ G0}Dq MTi
public Page(){ eC ~jgB
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} ->\N_|_
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/** construct the page by everyPage fk>l{W}e)
* @param everyPage 9\v.qo.
* */ ~m=$VDWm
public Page(int everyPage){ Z>8eD|m%2
this.everyPage = everyPage; "B#Y-
} A 4j<\xL
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/** The whole constructor */ c45tmul
public Page(boolean hasPrePage, boolean hasNextPage, sAi&A9"*
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int everyPage, int totalPage, Fn!SGX~kx$
int currentPage, int beginIndex){ ibJl;sJ
this.hasPrePage = hasPrePage; i\Yl
this.hasNextPage = hasNextPage; {I{3 (M#"
this.everyPage = everyPage; d$K=c1
this.totalPage = totalPage; I"1CgKYK^+
this.currentPage = currentPage; xO7Yt
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this.beginIndex = beginIndex; iK!dr1:wSw
} KmQ^?Ad-C
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/** 1Bg_FPu
* @return y"vX~LR
* Returns the beginIndex. ,/&Z3e
*/ ?;
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publicint getBeginIndex(){ 5`~mqqR5
return beginIndex; ?E<c[*F05
} ^av6HFQ
:a.0hes
/** $n-Af0tK
* @param beginIndex 0z`/Hn
* The beginIndex to set. nUc;/
*/ VD$Eb
publicvoid setBeginIndex(int beginIndex){ mV?&%>*(f
this.beginIndex = beginIndex; "Sjr_!u
} !
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/** 6NX3"i0eT
* @return _ h9o@
* Returns the currentPage. ',ZF5T5z@
*/ 2n|CD|V$ux
publicint getCurrentPage(){ DyfsTx
return currentPage; Mra35
} Q[PK`*2)
;cKH1
/** ;W{b $k@g
* @param currentPage MzzKJ;wbC6
* The currentPage to set. ^e%}[q[>|
*/ Mvb':/M
publicvoid setCurrentPage(int currentPage){ )KY:m |Z
this.currentPage = currentPage; g9KTn4
} aMTFW_w
^Kqf~yS%
/** GK?4@<fY
* @return .9h)bf+
* Returns the everyPage. *Qkc[XHqy
*/ =eBmBn
publicint getEveryPage(){ {.CMD9F[
return everyPage; qu~X.pW
} zizk7<?L.
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/** rk|@B{CA;
* @param everyPage Zx{96G+1
* The everyPage to set. bik*ZC?E
*/ >(3\kiYS
publicvoid setEveryPage(int everyPage){ T8XY fcc*h
this.everyPage = everyPage; U
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} g97]Y1g
r:&|vP
/** xAhxD|4_
* @return pQWHG#?7
* Returns the hasNextPage. #NN ewzC<*
*/ NfzF.{nh
publicboolean getHasNextPage(){ ^jD1vUL 2:
return hasNextPage; v`DI<Lt
} sx
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A:# k
/** DBs DkkB{
* @param hasNextPage gfy19c 9
* The hasNextPage to set. j6g@tx^)'
*/ 8=;k"
publicvoid setHasNextPage(boolean hasNextPage){ 'bu )M1OLi
this.hasNextPage = hasNextPage; >t <pFh
} OP! R[27>
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/** YF[f Z
* @return p
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* Returns the hasPrePage. 1;lmu]I>)
*/ @T:faJ5\'
publicboolean getHasPrePage(){ k< j"~S1
return hasPrePage; x,8<tSW)Z
} #=,imsW)
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/** nFM@@oA
* @param hasPrePage Ne6}oQy(S`
* The hasPrePage to set. 60}! LmL
*/ 9$1)k;ChP/
publicvoid setHasPrePage(boolean hasPrePage){ #VGjCEeU
this.hasPrePage = hasPrePage; ,EpH4*e
} A??@AP[7M
}#`:Qb \U
/** @f1*eo5f
* @return Returns the totalPage. V[;M&=,"
* y\c"b-lQX
*/ ,Zf
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publicint getTotalPage(){ o[\HOe~;
return totalPage; p9qKLJ*.C
} $m| V :/
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/** <a^Oj LLU
* @param totalPage Di5(9]o2
* The totalPage to set. [A2`]CE<@
*/ (Ddp|a"b
publicvoid setTotalPage(int totalPage){ .12aUXo(
this.totalPage = totalPage; ZcE_f>KV
} Vb|#MNf)
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} g"_C,XN
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 EbY,N:LK
'gMfN
个PageUtil,负责对Page对象进行构造: }8K4-[\
java代码: TbvtqM 0
b=;nm#cAI
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/*Created on 2005-4-14*/ ^K(^I*q
package org.flyware.util.page; An`3Ex[
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import org.apache.commons.logging.Log; .)tSg
import org.apache.commons.logging.LogFactory; XMIbUbUk-
~B i_7 Q
/** XGrue6ya
* @author Joa 23\RJpKb
* 0&+k.Vg
*/ 9xI GV!
publicclass PageUtil { zYER
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privatestaticfinal Log logger = LogFactory.getLog ,:Z^$
O[^%{'
(PageUtil.class); 7[#yu 2
A^ \.Z4=d"
/** 4u;9J*r4
* Use the origin page to create a new page -Z-f1.Dm5
* @param page )u%je~Vw
* @param totalRecords pKUP2m`MW
* @return K5>p89mZ
*/ 2}6%qgnT-
publicstatic Page createPage(Page page, int l |2D/K5
SLL3v,P(7
totalRecords){ 1T&Rc4$Sn7
return createPage(page.getEveryPage(), 7cDU2l
{Azn&|%.t
page.getCurrentPage(), totalRecords); 9pn>-1NJ
} BaI $S>/Q
o G*5f
/** 6fo3:P*O
* the basic page utils not including exception )- 15 N
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handler tC?=E#3V
* @param everyPage (& "su3z
* @param currentPage t_z>Cl^u
* @param totalRecords %M
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* @return page K7knK
*/ hg.#DxRi{
publicstatic Page createPage(int everyPage, int ?Ea;J0V
j l.p'$Fbn
currentPage, int totalRecords){ f
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everyPage = getEveryPage(everyPage); O|IG_RL]
currentPage = getCurrentPage(currentPage); BF*kb2"GZ6
int beginIndex = getBeginIndex(everyPage, $
i)bq6
^ 2GHe<Y
currentPage); 2,2Z`X
int totalPage = getTotalPage(everyPage, t.8 GT&p
2"P99$"
totalRecords); 6k{2 +P
boolean hasNextPage = hasNextPage(currentPage, {'sY|lou
N[]Hc
totalPage); 1d"Z>k:mn
boolean hasPrePage = hasPrePage(currentPage); XgN` 7!Z
zLs|tJOVp
returnnew Page(hasPrePage, hasNextPage, @+vXMJ $
everyPage, totalPage, >WJf=F`_H
currentPage, K5ZC:Ks
l:0s2
beginIndex); [v7^i_d
} $E<Esf$
fqX"Lus `=
privatestaticint getEveryPage(int everyPage){ y.5/?{GL
return everyPage == 0 ? 10 : everyPage; }VS3L_
;}/
} oF9
-&
s4Sd>D7
privatestaticint getCurrentPage(int currentPage){ KH)D08
return currentPage == 0 ? 1 : currentPage; oVA?J%EK
} N7'OPTKt&
Ds#/
privatestaticint getBeginIndex(int everyPage, int kIw`P[
E#J';tUQ
currentPage){ Wt)Drv{@ {
return(currentPage - 1) * everyPage; ;AR{@Fu.
} ~\ ,w {
WV3|?,y]qm
privatestaticint getTotalPage(int everyPage, int F|Mi{5G%
ZUz ^!d
totalRecords){ Re:jVJgBz
int totalPage = 0; Y$N)^=7
B]m@:|Q
if(totalRecords % everyPage == 0) 4c
oJRqf=
totalPage = totalRecords / everyPage; 3czeTj
else [U}+sTQ
totalPage = totalRecords / everyPage + 1 ; [Vd[-
*D o/+[Ae
return totalPage; ur
:i)~wXn
} u p.Q>28r
l Z#o+d2Y
privatestaticboolean hasPrePage(int currentPage){ lzw3= H
return currentPage == 1 ? false : true; ,NnhHb2\
} rG#Z=*b%
D3|oOOoG
privatestaticboolean hasNextPage(int currentPage, QM3,'?ekRH
f|^dD`
int totalPage){ 5MFxo63
return currentPage == totalPage || totalPage == X37 L\e[c
,yd
MU\so(
0 ? false : true; ]| N3eu
} k(zsm"<q
Fk(JSiU
6KD `oUx
} <%xS{!'}
kb[P\cRa
[:xiZ
~m|Mg9-
>=]'hyn]]
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 f;/QJ
??n*2s@t
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 /Q,{?';~
W@yJAQ
做法如下: c/B'jPt
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 N`)$[&NG]
b-3*Nl _%
的信息,和一个结果集List: 8G5Da|\
java代码: zBO(`=|
f|y:vpd%
J=pztASt
/*Created on 2005-6-13*/ V9ssH87#
package com.adt.bo; lKEkXO
I^oE4o
import java.util.List; jV(6>BAI_
dw.F5?j`b
import org.flyware.util.page.Page; Wf{O[yL*
sAg Kg=)
/** P&Pj>!T5
* @author Joa ]skkoM
*/ ?"z]A7<Hj
publicclass Result { mxb06u_
*3T|M@Y
private Page page; h" H2z1$
##Z_QB(;
private List content; b;)~wU=
%0? M?Jf
/** e</$ s
* The default constructor `R"I;qV
*/ #Rg|BfV-
public Result(){ 0* /{4)r
super(); BTM),
w2
} vD 5vbl
C7H/N<VAq
/** DJP2IP
* The constructor using fields -hkQ2[Ew#
* [`]4P&
* @param page e"
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* @param content %cE2s`
*/
9CCkqB/
public Result(Page page, List content){ )5|I_PXB
this.page = page; q~o,WZG
this.content = content; +za8=`2o
} U^qt6$bK
S1/`th
/** w[6J
`
* @return Returns the content. ['%69dPh
*/ xoOJauSX1
publicList getContent(){
-Ij&
return content; rHP%0f9:
} &-5_f*{
_-5,zPR
/** tgjr&G}a@0
* @return Returns the page. _z[#}d;k
*/ P ~PIMkt
public Page getPage(){ J)mhu}
return page; %F kMv
} v\`9;QV5
c{[q>@y
pK
/** A>{p2?`+!
* @param content Fq9Q+RNMZL
* The content to set. zD3mX<sw
*/ 9<Kj6t_
public void setContent(List content){ +:3*
this.content = content; gIA@l`"
} sBV4)xM
w&xDOyW]
/** O$IjNx
* @param page m^x6>9,
* The page to set. au,t%8AC
*/ ^<X@s1^#
publicvoid setPage(Page page){ <L&m4O#|
this.page = page; y<b{Ji e
} sl2@umR7%(
} p">EHWc}D
w1UA?+43
j[Uxa
7<H
|QL&
LHJ":^
2. 编写业务逻辑接口,并实现它(UserManager, r!,}Z=cGe
fvb=#58N_
UserManagerImpl) \P1=5rP
java代码: M4xi1M#%
N25V]
;;A2!w{}[i
/*Created on 2005-7-15*/ e L.(p
k^<
package com.adt.service; s|y:UgD
85;b9k&\M
import net.sf.hibernate.HibernateException; GJqE!I,.
*6(kbe s
import org.flyware.util.page.Page; `gKf#f
MQKfJru7
import com.adt.bo.Result; .5!t:FPOv
gl).cIp w
/** Et_V,s<|
* @author Joa 0| ;
.6\
*/ K!,<7[MBg
publicinterface UserManager { U?.9D
jSc#+_y
public Result listUser(Page page)throws (@WA1oNG
NAPX_B,6
HibernateException; 5JhdVnT_
:NJ(r(QG>
} V34hFa
-[L!3jU
;l}- Z@! /
1n\ t+F
;O<9|?
java代码: pStk/te,XK
]\ngX;h8G
5{$LsL
/*Created on 2005-7-15*/ OxGE%R,
package com.adt.service.impl; e6_ZjrQf
n&A'C\
import java.util.List; ^T~gEv
CIVnCy z
import net.sf.hibernate.HibernateException; -l}IZY
[=%TnT+^9
import org.flyware.util.page.Page; _20#2i&
import org.flyware.util.page.PageUtil; vy,&N^P
$)H@|<K
import com.adt.bo.Result; ,YhdY6
import com.adt.dao.UserDAO; Cye$H9 2
import com.adt.exception.ObjectNotFoundException; ={?vAb:
import com.adt.service.UserManager; 7H>@iI"?
OIl#DV.
/** ;+1RUv
* @author Joa XhsTT2B
*/ t*@z8<H
publicclass UserManagerImpl implements UserManager { KgN)JD>
ps$7bN C
private UserDAO userDAO; LK"
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fIGFHZy,
/** 8QK5z;E2~
* @param userDAO The userDAO to set. >M Jg ,
*/ kM`l
publicvoid setUserDAO(UserDAO userDAO){ Z/rTVAs@r
this.userDAO = userDAO; #yI.nzA*
} "n:{!1VGw
)etmE
/* (non-Javadoc) s( <uo{
* @see com.adt.service.UserManager#listUser D#S\!>m
OGiV{9U
(org.flyware.util.page.Page) 8P:
Rg%0)
*/ %P;Q|v6/|
public Result listUser(Page page)throws
Quf_'
)bx_;9Y{
HibernateException, ObjectNotFoundException { RllY-JBO
int totalRecords = userDAO.getUserCount(); ;WL1B
if(totalRecords == 0) W(RF n`g\
throw new ObjectNotFoundException Xtq{%
?X?&~3iD%
("userNotExist"); i
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page = PageUtil.createPage(page, totalRecords); c"!lwm3b
List users = userDAO.getUserByPage(page); 09o~9z0
returnnew Result(page, users); Z>)][pL
} G;3~2^lB\
zY+Fl~$S
} >+5?F*`\D*
{K#NB_*To
~el3I=KC}
P'MY[&|mM'
Jw~( G9G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ``ekR6[ 8c
*Ywpz^2?:
询,接下来编写UserDAO的代码: 80M;4nH^5
3. UserDAO 和 UserDAOImpl: R_sC! -
java代码: 2wqk,c[]
8vk..!7n}
,7,g%?_P
/*Created on 2005-7-15*/ w<9>Q1(
package com.adt.dao; w#i[_
:Sg_tOf
import java.util.List; p
(FlR?= S
$N2SfyX7
import org.flyware.util.page.Page; bN^O}[
ENh!N4vbO
import net.sf.hibernate.HibernateException; 9t@:4O
~](fFa{
/** OPBt$Ki
* @author Joa UueD(T;p
*/ B~'MBBD"
publicinterface UserDAO extends BaseDAO { 0:KE@=
e$c?}3E!z
publicList getUserByName(String name)throws <ktzT&A
)x#5Il
H
HibernateException; ]<DNo&fw
9]$8MY
publicint getUserCount()throws HibernateException; ,D6v4<jh
m\/(w_/?
publicList getUserByPage(Page page)throws vhr+g 'tf
}G$]LWgQx
HibernateException;
yz+, gLY
~#\i!I;RY}
} "x'),
h x6;YV
!S%6Uzsj
S~$'WA
:PbDU$x
java代码: Vv$HR
PZ8U6K'
nRhrWS
/*Created on 2005-7-15*/ q^rl)
package com.adt.dao.impl; k&hc m
2Ha5yaTL
import java.util.List; +)nT|w45
iV.p5FD
import org.flyware.util.page.Page; .'[/|4H
,G^[o,hS
import net.sf.hibernate.HibernateException;
>95TvJ
import net.sf.hibernate.Query; Hg}I]!B
{mE! Vf
import com.adt.dao.UserDAO; p<WFqLe(":
7=4 A;Ybq
/** FDFH,J`_
* @author Joa RaSz>-3d
*/ e2$]g>
public class UserDAOImpl extends BaseDAOHibernateImpl .V6-(d
gM;}#>6
implements UserDAO { XM
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[AEBF2OIv
/* (non-Javadoc) o7&4G$FX~
* @see com.adt.dao.UserDAO#getUserByName BdbJ< Is
FqA3{
(java.lang.String) D
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*/ sPNfbCOz
publicList getUserByName(String name)throws (g :p5Rl
M/V(5IoP(
HibernateException { +V v+K(lh$
String querySentence = "FROM user in class z*~YLT&
t0PQ~|H<KV
com.adt.po.User WHERE user.name=:name"; NnxM3*
Query query = getSession().createQuery 9Z\z96O-
V'Y{v
(querySentence); xFp<7p
L
query.setParameter("name", name); aI#4H+/
return query.list(); #`tD1T{;
}
yeD_j/
U6 82Th
/* (non-Javadoc) ?SY<~i<K-
* @see com.adt.dao.UserDAO#getUserCount() 71B3a
*/ YTY%#"
publicint getUserCount()throws HibernateException { w#PZu+
int count = 0; ZofHic
String querySentence = "SELECT count(*) FROM U2*6}c<
^o<:;{
user in class com.adt.po.User"; SA6hbcYk
Query query = getSession().createQuery FyD.>ot7M
@%i>XAe#0
(querySentence); (0*v*kYdL+
count = ((Integer)query.iterate().next nR5bs;gk"
]>:^d%n,}
()).intValue(); 67<CbQZoN3
return count; `rWB`q|i<
} CKARg8o
6i@ub%qq
/* (non-Javadoc) 4 9w=kzo
* @see com.adt.dao.UserDAO#getUserByPage YaFcz$GE_
-oBI+v&
(org.flyware.util.page.Page) AfWl6a?T8:
*/ rFag@Z"["
publicList getUserByPage(Page page)throws #!!AbuhzK{
OKY+M^PP
HibernateException { 5S/>l_od$2
String querySentence = "FROM user in class G_oX5:J*
$fArk36O#
com.adt.po.User"; |uha 38~
Query query = getSession().createQuery *Jnh";~b
Md(JIlh3
(querySentence); q&M:17+:Q
query.setFirstResult(page.getBeginIndex()) K_-MkY?+
.setMaxResults(page.getEveryPage()); =mrY/:V
return query.list(); J6|JWp
} C@@$"}%v2
AF#_nK)@
} O.:I,D&]
`!c,y~r[
.K9l*-e[=
cqQRU
GfsBQY/
至此,一个完整的分页程序完成。前台的只需要调用 GEE
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dXP6"V@iI
userManager.listUser(page)即可得到一个Page对象和结果集对象 9={N4}<
>iy^$bqF
的综合体,而传入的参数page对象则可以由前台传入,如果用 Fe="EDh
?R?Grw)`H
webwork,甚至可以直接在配置文件中指定。 r=csi
CM 9P"-
下面给出一个webwork调用示例: i>Iee^_(
java代码: 7Jx%JgF
)*[
""&
.)ST[G]WK
/*Created on 2005-6-17*/ O<`R~
package com.adt.action.user; &telCg:
_om[VKJd
import java.util.List; w??c1)
nUqy1(
import org.apache.commons.logging.Log; N#Ag'i4HF
import org.apache.commons.logging.LogFactory; GoeIjuELR
import org.flyware.util.page.Page; }'`xu9<
:HZ;Po
import com.adt.bo.Result; _'c+fG
\
import com.adt.service.UserService; %8Yyj{^!(
import com.opensymphony.xwork.Action; V<-htV
*-z4 <LAa
/** 94z8B;+H]
* @author Joa qz:]-A
*/ A[9NP-~
publicclass ListUser implementsAction{ a;&}zcc*
fOW_h
privatestaticfinal Log logger = LogFactory.getLog ??I:H
jaqV[*440U
(ListUser.class); 6$z'wy/*
4g!7
4a
private UserService userService; F!R2_89iy
" dT>KQ
private Page page; !Zj#.6c9
no3Z\@%
privateList users; cj^bh
&|z|SY]DL
/* _?Ckq
* (non-Javadoc) )OUU]MUH
* c! ~T2t
* @see com.opensymphony.xwork.Action#execute() e?vj+ZlS$f
*/ i puo}
publicString execute()throwsException{ WY.5K
=}
Result result = userService.listUser(page); U3VT*nj'
page = result.getPage(); S>EDL
users = result.getContent(); E!dp~RwZu
return SUCCESS; ;Xh5oB\)W
} [0(mFMC`
cyb(\ fsC
/** \>;%Ji
* @return Returns the page. &E]"c]i+
*/ S~|tfJpL
public Page getPage(){ D2?S,9+E_
return page; iPkT*Cl8
} ~*kK4]lP
<)J55++
/** uH]
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* @return Returns the users. W+/2c4$F3
*/ w<mqe0
publicList getUsers(){ VwC4QK,d;
return users; fr]Hc+7
} UhBz<>i;!
'v+96b/;
/** /=-h:0{M
* @param page 5E.vje{U;
* The page to set. ]]3Q*bq4
*/ X_!$Pk7ma
publicvoid setPage(Page page){ sOC|
B
this.page = page; p Mh++H]"
} )=Y-f?o!
G
"c/a8
/** R{ 4u|A?9
* @param users T#/ 11M$uQ
* The users to set. AD,@,|A
*/ 4NI'(#l
publicvoid setUsers(List users){ _&=9 Ke
this.users = users; ? 9qAe
} 65t[vi*C
X)y*#U
/** lkyJ;}_**
* @param userService "|\94
* The userService to set. 3} l;
*/ %D. @L
publicvoid setUserService(UserService userService){ [@zkv)D6
this.userService = userService; )Jmw|B
} vo.EM1x
} 5 5a@)>h
+
p'\(Z(
@}Pw0vC
s?HsUD$b
r@;$V_I
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, '2j~WUEmg
sgR
9d
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 zEAx:6`c
4bWfx_0W
么只需要: }el,^~
java代码: &4[<F"W>47
`c> A>c|
jw/wcP
<?xml version="1.0"?> J511AoQ{R
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork x[Hhj'
;Xz(B4 N~o
1.0//EN" "http://www.opensymphony.com/xwork/xwork- aTi0bQW{
`yy%<&
1.0.dtd"> <'VA=orD
/^NJ)9IB
<xwork> x={kjym L
hgNY[,
<package name="user" extends="webwork- ;A`IYRzt
*-+C<2"
interceptors"> ;k-g_{M
}D(DU5r
<!-- The default interceptor stack name _8Pmv$
yFIl^Ck%
--> JHHb |
<default-interceptor-ref #V,LNX)
9{T 8M
name="myDefaultWebStack"/> hwc:@'
1mAUEQ!
<action name="listUser" Al)lWD}j2g
}7otuO(pRo
class="com.adt.action.user.ListUser"> se}pdL}
<param T,A!5V>cX
x4/T?4k
name="page.everyPage">10</param> Bi %Z2/
<result ?]759,Q3L
;B,nzx(L
name="success">/user/user_list.jsp</result> 6oPUYn-
</action> ^f!Zr
8Ix-i
</package> $b&BH'*'~
,M| QN*
</xwork> PEK.Kt\M
B!$V\Gs
cu)@P 0I
[%HYh7ua<
.dy#n`eP
c8H9_6
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 2(@LRl>:
nYmf(DV
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。 9(i0"hS^
&Xj {:s#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 5)h+(u C3
\H},ouU
B4PW4>GF
g/fp45s
T2;v<(
我写的一个用于分页的类,用了泛型了,hoho .~FKyP>[$
3U :YA&K(
java代码: cg>!<T*
k8!hvJ)?
UUt~W
package com.intokr.util; z_5rAlnwT.
V,99N'o~x
import java.util.List; ahK?]:&QO
,+swH;=7#r
/** -6.i\
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* 用于分页的类<br> {o Q(<&Aw
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Yg\{S<wr
* 5]A$P\7~1
* @version 0.01 P]~N-xdV
* @author cheng m^W*[^p
*/ ;$E~ZT4p
public class Paginator<E> { \SoYx5lf
privateint count = 0; // 总记录数 KqT#zj
privateint p = 1; // 页编号 W)G2Cs?p
privateint num = 20; // 每页的记录数 }Rf}NWU)|
privateList<E> results = null; // 结果 xkk@{}J\
Qivf|H619
/** G.A=hGw
* 结果总数 SaX,^_GY
*/ lo IL{2
publicint getCount(){ 0R2S@4%Y
return count; bn^mL~
} -N /8Ho
}.fZy&_
publicvoid setCount(int count){ GqmDDL1
this.count = count; N2+mN0k;
} D;16}D
p 02nd.R6
/** f}evw K[S
* 本结果所在的页码,从1开始 F:[Nw#gj/
* ^VM"!O;h{
* @return Returns the pageNo.
o>/uW8
*/ s=
-WB0E
publicint getP(){ i}
NkHEK
return p; 1Ovx$*
} *o:BoP=S
Qd&d\w/
/** yH0yO*RZ
* if(p<=0) p=1 vu
!j{%GO
* 9XJ9~I?
* @param p .P|+oYT&g
*/ 7$Z)fkx.
publicvoid setP(int p){ >S-N|uR6
if(p <= 0) t
wa(M?
p = 1; "G i+zkVm
this.p = p; #'G7mAoA
} 2yi*eR
B J:E,P`_
/** dd?x5|/#
* 每页记录数量 #2ZrdD"5kQ
*/ ;:8jxkx6%
publicint getNum(){ Eb4< 26A
return num;
Xv?
S
} $w";*">:0
?vL^:f["
/** }5fI*v
* if(num<1) num=1 )Bm^aMVl3
*/ f//j{P[
publicvoid setNum(int num){ oJ4mxi@|#
if(num < 1) ';fU.uy
num = 1; "R\\\I7u
this.num = num; ^Yf)lV&[
} dctA`W@:-
~,M;+T}[r
/** Q9 x` Uy
* 获得总页数 M Z|c7f&`
*/ jiw`i
publicint getPageNum(){ R"8})a
gw
return(count - 1) / num + 1; ^,ZvKA"}+/
} ya*q; D
L&3Ar'
/** !)51v {
* 获得本页的开始编号,为 (p-1)*num+1 W~+!"^<n
*/ g[D,\
publicint getStart(){ zn?a|kt
return(p - 1) * num + 1; '%eaK_+7
} ^}Dv$\;6
|+$j(YuH
/** h!t2H6eyF
* @return Returns the results. p[k9C$@e}
*/ +"N<-
publicList<E> getResults(){ 7Da^Jv k
return results; >FEQtD~F
} u}@%70A
c-3Y SrY
public void setResults(List<E> results){ )n3biQL_
this.results = results; ~;O=
7
} Y+PvL|`O
j.yr5%
public String toString(){ l66ipgw_^I
StringBuilder buff = new StringBuilder no\}aTx
;>QK}#'
(); WkU)I2oH
buff.append("{"); Tr}$Pb1
buff.append("count:").append(count); NNREt:+kr
buff.append(",p:").append(p); g^<q L|
buff.append(",nump:").append(num); ke;*uS
buff.append(",results:").append d= T9mj.@
!tFU9Zt
(results); V"Y
Fu^L
buff.append("}"); |0vHy7CE
return buff.toString(); [#3Cg%V
} E6wST@r
@u'27c_<d3
} /iJcy:J
~M9n<kmE
\SH D