Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 pQD8#y)` C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ghz)=3
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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 z^]nP87
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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 IiL?@pIq
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分页支持类: ~2H)#`\ac8
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java代码: SU^/qF%8
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package com.javaeye.common.util; _IGQ<U <z
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import java.util.List; uG<+IT|x
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publicclass PaginationSupport { #~Q0s)Ze
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publicfinalstaticint PAGESIZE = 30; f;*\y!|lg~
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privateint pageSize = PAGESIZE; tfsG
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privateList items; 3j2}n
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privateint totalCount; n*V^Qf
7 @ZL(G
privateint[] indexes = newint[0]; _\"?:~rUN
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privateint startIndex = 0; #Ew}@t9
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public PaginationSupport(List items, int Q8O38uZ
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totalCount){ [@(zGb8
setPageSize(PAGESIZE); V%+KJ}S!Z
setTotalCount(totalCount); FD8aO?wvg
setItems(items); E+_}8J .
setStartIndex(0); "8N]1q:$4
} Yq.Omr!
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public PaginationSupport(List items, int {3?g8e]zr
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totalCount, int startIndex){ BZE19!
setPageSize(PAGESIZE); mu(S9
setTotalCount(totalCount); ?/O+5rjA
setItems(items); /OZF3Pft
setStartIndex(startIndex); $0WAhq
} s%Z3Zj(,8(
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public PaginationSupport(List items, int ,ihTEw,t(
a/_ `1
totalCount, int pageSize, int startIndex){ 3Z`oI#-x
setPageSize(pageSize); .DT1Jvl
setTotalCount(totalCount); pB )nQ5l'
setItems(items); 6(wpf^br2
setStartIndex(startIndex); [scPs,5Y
} 2o,%O91p
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publicList getItems(){ U7Ps2~x3
return items; \KG{
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} z19y>j
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publicvoid setItems(List items){ 7;Wj ^#
this.items = items; \jC}>9
} 4Vt YR
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publicint getPageSize(){ >%xJ e'
return pageSize; J^u8d?>r
} @o8\`G
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publicvoid setPageSize(int pageSize){ H -`7T;t~
this.pageSize = pageSize; DS^PHk39
} jn]{|QZ
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publicint getTotalCount(){ Iu%S><'+
return totalCount; CFVe0!\
} W"$'$h
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publicvoid setTotalCount(int totalCount){ 7D4P=$UJp
if(totalCount > 0){ }F-W OQ
this.totalCount = totalCount; /QG8\wXE2
int count = totalCount / Mk7#qiPo
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pageSize; Hl] 3F^{
if(totalCount % pageSize > 0) .'
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count++; ^oj)#(3C
indexes = newint[count]; =6/0=a[
for(int i = 0; i < count; i++){ `_<K#AG Ai
indexes = pageSize * >0{{loqq
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i; Cdc6<8
} 1}9@aKM
}else{ dqnxhN+&
this.totalCount = 0; S=2-<R
} fk9FR^u
} 9"oc.ue.2D
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publicint[] getIndexes(){ Q4C28-#
return indexes; u3Ua>A-
}
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publicvoid setIndexes(int[] indexes){ (`xhh
this.indexes = indexes; ?> }bg
} 2\W[ ItxL0
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publicint getStartIndex(){ 5|";L&`
return startIndex; nRJcYl~
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} Td}#o!4!
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publicvoid setStartIndex(int startIndex){ e!Y:UB2
7u
if(totalCount <= 0) o`7Bvh2
this.startIndex = 0; //Ck1cI#h
elseif(startIndex >= totalCount) 0[jy
this.startIndex = indexes q B5cF_
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[indexes.length - 1]; ,ie84o
elseif(startIndex < 0) 7i,}F|#8
this.startIndex = 0; sd
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else{ IZoa7S&t
this.startIndex = indexes 1W;q(#q
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[startIndex / pageSize]; j!xt&t4D
} 1 f).J
} I HgYgn
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publicint getNextIndex(){ tUH#%
int nextIndex = getStartIndex() + Y]Td+Zi
+2!F6"hP
pageSize; ~bhesWk8!
if(nextIndex >= totalCount) XTyJ*`>
return getStartIndex(); }hv>LL
else 22)2olU
return nextIndex; weYP^>gH'
} ?>LsIPa
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publicint getPreviousIndex(){ 7g[T#B'/x,
int previousIndex = getStartIndex() - F_$eu-y
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pageSize; !O~EIz
if(previousIndex < 0) y4^6I$M7V
return0; !inonR
else dnSjXyjFB
return previousIndex; Ni7~
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} 9K-=2hvv
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} HNu/b)-Rb
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抽象业务类 e/'d0Gb-
java代码: h/W@R_Y
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/** E`}KVi57
* Created on 2005-7-12 g-q~0
*/ ,dOd3y'y
package com.javaeye.common.business; wM8Gz.9,
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import java.io.Serializable; ~&8ag`
import java.util.List; M#c.(QdF
-}_-#L!Q
import org.hibernate.Criteria; ep* (
import org.hibernate.HibernateException; r~N0P|Tq
import org.hibernate.Session; h(*!s`1
import org.hibernate.criterion.DetachedCriteria; { AdPC?R`
import org.hibernate.criterion.Projections; gpB3\
import Q&S\?cKe
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org.springframework.orm.hibernate3.HibernateCallback; Rs_bM@
import `VM@-;@w
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org.springframework.orm.hibernate3.support.HibernateDaoS 8pp^
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upport; A8Tq2]"* S
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import com.javaeye.common.util.PaginationSupport; z-<U5-'
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public abstract class AbstractManager extends N,6(|,m
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HibernateDaoSupport { zcnp?%
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privateboolean cacheQueries = false; ="hh=x.5J
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privateString queryCacheRegion; =QXLr+
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publicvoid setCacheQueries(boolean U2l7@uDr;
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cacheQueries){ ]c%yib
this.cacheQueries = cacheQueries; vs}_1o
} B/u0^!
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publicvoid setQueryCacheRegion(String @5jJoy(mX@
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queryCacheRegion){ 6fV%[.RR
this.queryCacheRegion = 9un* 1%
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queryCacheRegion; Yz4)Q1
} MM8@0t'E
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publicvoid save(finalObject entity){ L>VZ-j
getHibernateTemplate().save(entity); DA;,)A&=Q
} "5Orj*{
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publicvoid persist(finalObject entity){ 6B>1"h%Wf
getHibernateTemplate().save(entity); -?{bCq
} szW_cjS
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publicvoid update(finalObject entity){ (T+fO}0
getHibernateTemplate().update(entity); wn2+4> |~p
} xrb %-vT
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publicvoid delete(finalObject entity){ F/GfEMSE
getHibernateTemplate().delete(entity); =8FV&|fP
} "|<6bA
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publicObject load(finalClass entity, 3{OY&
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finalSerializable id){ itV@U
return getHibernateTemplate().load {!h|(xqN+
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(entity, id); U,Py+c6
} Teq1VK3Hr
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publicObject get(finalClass entity, a![x^@nF
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finalSerializable id){ d67Q@')00
return getHibernateTemplate().get ]XX9.Xh=-
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(entity, id); c|?0iN
} v[4A_WjT
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publicList findAll(finalClass entity){ IoUQ~JviA
return getHibernateTemplate().find("from 6b&<5,=d:
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" + entity.getName()); "o.V`Bj
} {@j0?s
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publicList findByNamedQuery(finalString 1NJ,If]
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namedQuery){ 022nn-~
return getHibernateTemplate mY[s2t
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().findByNamedQuery(namedQuery); pe(31%(h
} %g1{nGah
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publicList findByNamedQuery(finalString query, Mle@.IIT
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finalObject parameter){ (Ic{C5'
return getHibernateTemplate %tx~CD
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().findByNamedQuery(query, parameter); z@@w?>*
} N$u;Q(^
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publicList findByNamedQuery(finalString query, (pY'v/ a-
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finalObject[] parameters){ )nJo\HFXv
return getHibernateTemplate c6zghP3dR
fa#xEWaFr
().findByNamedQuery(query, parameters); b(@[Y(_R
} F!v`._]
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publicList find(finalString query){ o5~o Rmsr
return getHibernateTemplate().find F3k]*pk8w
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(query); }9Yd[`
} QP+zGXd}(
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publicList find(finalString query, finalObject BLc&q)
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parameter){ BI9~%dm
return getHibernateTemplate().find 77y_?di^I
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(query, parameter); @
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} h4@v.GI
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public PaginationSupport findPageByCriteria WH`E=p^x4
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(final DetachedCriteria detachedCriteria){ 9OIX5$,S;
return findPageByCriteria v=n'#:k
@WcK<Qho
(detachedCriteria, PaginationSupport.PAGESIZE, 0); (W*~3/@D
} z\iz6-\&y
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4
public PaginationSupport findPageByCriteria K(*QhKX
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(final DetachedCriteria detachedCriteria, finalint w-~u[c
2^-Z17Z}
startIndex){ @S#>:o|
return findPageByCriteria hVvPI1[2
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(detachedCriteria, PaginationSupport.PAGESIZE, j@OGl&'^-
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startIndex); fBgW0o.Bu
} {/f\lS.5g
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public PaginationSupport findPageByCriteria *Q=3v
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(final DetachedCriteria detachedCriteria, finalint 8<z]rLQw?%
}(}+I}&~
pageSize, zj G>=2
finalint startIndex){ IfyyA
return(PaginationSupport) <@;Y.76~
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getHibernateTemplate().execute(new HibernateCallback(){ -b1VY4m-
publicObject doInHibernate o_un=ygU
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(Session session)throws HibernateException { 1PwqWg-\\
Criteria criteria = ]<3$Sx_{y
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detachedCriteria.getExecutableCriteria(session); AEjkqG4qv
int totalCount = ts2;?`~
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((Integer) criteria.setProjection(Projections.rowCount [/.5{|&GSt
VUfV=&D-*g
()).uniqueResult()).intValue(); FScE3~R
criteria.setProjection Q4YIKNN|7
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(null); vIk;x
List items = ,^dyS]!d$
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criteria.setFirstResult(startIndex).setMaxResults vo'=d"zm
yn;h.m [):
(pageSize).list(); \k6Ho?PL
PaginationSupport ps = +.i?UHNB
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new PaginationSupport(items, totalCount, pageSize, C^uH]WO
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startIndex); PA5_
return ps; O0?.$f9 s
} |T53m;D
}, true); ],rtSUO
} >eHSbQu/Bu
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public List findAllByCriteria(final qPgLSZv
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DetachedCriteria detachedCriteria){ Nr.maucny
return(List) getHibernateTemplate 3EGQ$
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().execute(new HibernateCallback(){ Z<@Kkbj
publicObject doInHibernate <|= UrG
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(Session session)throws HibernateException { 3?Ckk{)&
Criteria criteria = e=b>:n
qMD!No
detachedCriteria.getExecutableCriteria(session); W}6(; tI
return criteria.list(); _sU| <1
} l V[d`%(
}, true); {3RY4HVT?
} sS$"6
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public int getCountByCriteria(final Z
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DetachedCriteria detachedCriteria){ 79:Wo>C3-
Integer count = (Integer) p1B~:9y9X
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getHibernateTemplate().execute(new HibernateCallback(){ ~.4-\M6[
publicObject doInHibernate TV$Pl[m
(<?6X9F:N
(Session session)throws HibernateException { V=";vRS8
Criteria criteria = ?2ZggV
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detachedCriteria.getExecutableCriteria(session); ^WDAW#f*<
return )+]8T6~
N
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criteria.setProjection(Projections.rowCount : `D[0
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()).uniqueResult(); hX#s3)87
} ]d#Lfgo
}, true); 3`@alhD'
return count.intValue(); (eS/Q%ZGK
} w9D<^(_}/
} FYIzMp.4
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用户在web层构造查询条件detachedCriteria,和可选的 2mS3gk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <b74L
et|P5%G
PaginationSupport的实例ps。 =j[zMO
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ps.getItems()得到已分页好的结果集 fm2,Mx6
ps.getIndexes()得到分页索引的数组 5>.)7D%
ps.getTotalCount()得到总结果数 [uxhdR`T
ps.getStartIndex()当前分页索引 wT?.Mte
ps.getNextIndex()下一页索引 G)28#aH
ps.getPreviousIndex()上一页索引 $YvT*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 td^2gjr^5
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 aVv$k
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一下代码重构了。 $Xf1|!W%a%
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我把原本我的做法也提供出来供大家讨论吧: }>vf(9sF`
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首先,为了实现分页查询,我封装了一个Page类: ;2"#X2B
java代码: A:Z$i5%'
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/*Created on 2005-4-14*/ eCB(!Y|
package org.flyware.util.page; a
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/** -|^}~yOx0=
* @author Joa b#0y-bR
* Z5juyzj
*/ 7sECbbJT
publicclass Page { 5Cxh>,k
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/** imply if the page has previous page */ BcaMeb-Z
privateboolean hasPrePage; kR%bdN
WrhC
q6
/** imply if the page has next page */ +}c
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privateboolean hasNextPage; 4,L(
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/** the number of every page */ Q!/<=95E
privateint everyPage; xlVQ[Mt
gwk$|aT@
/** the total page number */ ia15r\4j)
privateint totalPage; <{@?c
MdK!Y
/** the number of current page */ .J' 8d"+
privateint currentPage; 4?XX_=+F|
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/** the begin index of the records by the current _[8xq:G
87%t=X
query */ P9Hv){z
privateint beginIndex; ^_b+o
bF %#KSVw
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/** The default constructor */ lTe}[@(
public Page(){ a5WVDh,cR
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} LLv~yS O
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/** construct the page by everyPage 0gPz|v>z
* @param everyPage xkR--/f
* */ "-xm+7
public Page(int everyPage){ r{qM!(T
this.everyPage = everyPage; SeAokz>
} uEQH6~\{Nl
Tz .!
/** The whole constructor */ $Tu%dE(OF
public Page(boolean hasPrePage, boolean hasNextPage, wVk2Fr(
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int everyPage, int totalPage, R`ajll1
int currentPage, int beginIndex){ =O~1L m;
this.hasPrePage = hasPrePage; 2%0zPflT
this.hasNextPage = hasNextPage; uyP)5,
this.everyPage = everyPage; /6}4<~~4TA
this.totalPage = totalPage; ?RGL0`Lg
this.currentPage = currentPage; GutH}Kz"&
this.beginIndex = beginIndex; yA*~O$~Y
} *v3/8enf
aNb=gjLpt
/**
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* @return 1\q(xka{
* Returns the beginIndex. Sr~zN:wn
*/ (8o~ XL
publicint getBeginIndex(){ B1m@
return beginIndex; \~:Kp
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} 3:jKuOX
z<c^<hE:l
/** %Rv&VFg
* @param beginIndex BDZB;DPb
* The beginIndex to set. eKn&`\j6
*/ W>eJGZ<
publicvoid setBeginIndex(int beginIndex){ b_-ESs]g
this.beginIndex = beginIndex; +<6L>ZAL
} E&V"z^qs_
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/** pI7\]e
* @return e8gJ }8Fj
* Returns the currentPage. @& #df
*/ {U(-cdU{e`
publicint getCurrentPage(){ UK+;/Mtg
return currentPage; qdh;zAMx
} |J2_2a/"
a*hOT_;#
/** 5%D:wS1
* @param currentPage u7G@VZ Ux5
* The currentPage to set. 'vj45b
*/ L?&+*|VxI
publicvoid setCurrentPage(int currentPage){ .Tt \U
this.currentPage = currentPage; x3T)/'(
} O_0|Q@
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/** {g\Yy(r
* @return sLK J<=0i
* Returns the everyPage. 1B=vrGq
*/ Da1BxbDeI
publicint getEveryPage(){ =[(1u|H9
return everyPage; X;flA*6V
} .g DWv
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/** G40,KCa
* @param everyPage NUiZ!&
* The everyPage to set. n )YNt
*/ cyA|6Ltg%
publicvoid setEveryPage(int everyPage){ C$oY,A,
this.everyPage = everyPage; l_iucN
} 7^'TU=ss_
9>u2;
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/** v^y3r
* @return A=!&2(
* Returns the hasNextPage. }
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*/ xy46].x-
publicboolean getHasNextPage(){ wx -NUTRim
return hasNextPage; z %{>d#rw
} Mcc774'*9
jVL<7@_*
/** ^"v~hjM#
* @param hasNextPage (f5!36mz
* The hasNextPage to set. J|_&3@r
*/ ^M6v;8EU
publicvoid setHasNextPage(boolean hasNextPage){ [ik D4p=
this.hasNextPage = hasNextPage;
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} #rMMOu9r2
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/** D/:~#)
* @return QR2J;Oj_
* Returns the hasPrePage. rJ ?Y~Q
*/ mm/U9hbp%
publicboolean getHasPrePage(){ I?dh"*Js&
return hasPrePage; -VD[iH
} xb0hJ~e
^tsIgK^9H
/** *!%y.$\cE
* @param hasPrePage K6~N{:.s
* The hasPrePage to set. ??=CAU%\
*/ /ivt 8Uiw
publicvoid setHasPrePage(boolean hasPrePage){ #9EpQc[4
this.hasPrePage = hasPrePage; GV6!`@<
} W*;~(hDz
'IP'g,o++
/** su j? e6
* @return Returns the totalPage. GBtBmV/`
* '@2pOq
*/ 5[`!\vCiZ
publicint getTotalPage(){ M |?qSFv:
return totalPage; Y oNg3
} T
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d]VL(&
/** Qc\JUm]
* @param totalPage K8Gc5#OF
* The totalPage to set. |@]J*Kh
*/ =+~e44!~D
publicvoid setTotalPage(int totalPage){ Un^QNd>
this.totalPage = totalPage; !jMa%;/
} H:#b(&qw2
?(Dkh${@
} 4LtFv)i
K6@QZc5.!
=#^%; 6 6z
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% [
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ldrKk'S,B
cbsy&U
个PageUtil,负责对Page对象进行构造: zBay 3a
java代码: b=:AFs{
N/DcaHFYo
QOlm#S
/*Created on 2005-4-14*/ "^ydoRZ
package org.flyware.util.page; H!4!1J.=xw
;TF(opW:
import org.apache.commons.logging.Log; Bt[`p\p@
import org.apache.commons.logging.LogFactory; z!)_'A
3qiE#+dC
/** a-4'jT:
* @author Joa _xI'p6C
* qw&Wfk\}
*/ {CR~G2Z
publicclass PageUtil { BZQ98"Fz*
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privatestaticfinal Log logger = LogFactory.getLog C 6Bh[:V&
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<q?=
(PageUtil.class); :1q+[T/ @
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/** -_
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* Use the origin page to create a new page bRJYw6oA<
* @param page yTz@q>6s-
* @param totalRecords *;Dd:D9
* @return 1s-k=3)
*/ x6* {@J&5*
publicstatic Page createPage(Page page, int kCL)F\v"iT
I$\dT1m$
totalRecords){ Ljq/f&
c
return createPage(page.getEveryPage(), $@FD01h.t3
m/|>4~
page.getCurrentPage(), totalRecords); (Z=ziopDE
} pM@|P,w {
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/** /gL(40
* the basic page utils not including exception v{i'o4
!(*mcYA*W
handler gq*- v:P>
* @param everyPage Rs_@L}U..
* @param currentPage -\6tVF11z
* @param totalRecords OwwH 45
* @return page \bCm]wR
*/ Vg#s
publicstatic Page createPage(int everyPage, int -i V&-oP
5UVQ48aT
currentPage, int totalRecords){ +[UFf3(ON
everyPage = getEveryPage(everyPage); wA+J49
currentPage = getCurrentPage(currentPage); ^uW](2
int beginIndex = getBeginIndex(everyPage, _YWw7q
H?sl_3-#
currentPage); 9.qI hg
int totalPage = getTotalPage(everyPage, >>rW-&
?t'ZX~k
totalRecords); 4HVZ;,q
boolean hasNextPage = hasNextPage(currentPage, Lt8chNi
[
XASoS5
totalPage); lJi'%bOi
boolean hasPrePage = hasPrePage(currentPage); ME[Wg\
gAhCNOp
returnnew Page(hasPrePage, hasNextPage, %RL\t5TV
everyPage, totalPage, Kf76./
currentPage, LZMdW
#,[
3%/]y=rA
beginIndex); %.r{+m
} r) T^ Td1
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privatestaticint getEveryPage(int everyPage){ <^UB@'lCm
return everyPage == 0 ? 10 : everyPage; 9U>ID{
} LG [2u
g^NdN46%
privatestaticint getCurrentPage(int currentPage){ 5~<>h~yJ
return currentPage == 0 ? 1 : currentPage; )-Zpr1kD
} 6TbDno/!'
F@kOj*5,[
privatestaticint getBeginIndex(int everyPage, int U#ueG
o{4ya jt
currentPage){ tE]g*]o
return(currentPage - 1) * everyPage; ,ZJI]Q=!
} COOazXtW
VCiJ]$`M
privatestaticint getTotalPage(int everyPage, int zid?yuP
@z EEX9U
totalRecords){ Y$--Hp4
int totalPage = 0; c,Zs.
kC
" 6~pTHT
if(totalRecords % everyPage == 0) U>(5J,G
totalPage = totalRecords / everyPage; 7OS\j>hb~
else hQ i[7r($8
totalPage = totalRecords / everyPage + 1 ; t^&:45~Q
Oo`P +S#
return totalPage; i92{N$*x
} &jl'1mZ
:@wO'
o
privatestaticboolean hasPrePage(int currentPage){ iH9g5G`O
return currentPage == 1 ? false : true; $N5VoK
} k)'hNk"x
:M`|*~V~$
privatestaticboolean hasNextPage(int currentPage, q+x4Od3
Y)N(uv6
int totalPage){ y rdJX
return currentPage == totalPage || totalPage == +o?.<[>!GR
F4k<YU
0 ? false : true; weT33O"!1
} HyiuU`
VD,F?L!
6.6~w\fR8
} yH|ucN~k5S
T73oW/.0X?
WnLgpt2G
{dg3 qg~
E(4ti]'4
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。 b5_A*-s$M
[])M2_
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 la8se=^
Vvm6T@b M8
做法如下: b*nytF
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;J2U5Y NO
Gnl6>/L,
的信息,和一个结果集List: $9y]>R
java代码: 'P)xY-15
lT@5=ou[
@?aNvWeavH
/*Created on 2005-6-13*/ x]euNa
package com.adt.bo; Eof1sTpA
"]LNw=S
import java.util.List; kNI m90,g
elWN-~
import org.flyware.util.page.Page; enF.}fo]
Z"lL=0rY/
/** \C
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* @author Joa B+jT|Y'
*/ $sU?VA'h
publicclass Result { nOkX:5
zr&K0a{hc
private Page page; L-Xd3RCD
Fz?ON1\
private List content; Nk3]<#$
Y">Q16(
/** )FMpfC>An
* The default constructor 3a:(\:?z
*/ [=Np.:Y%
public Result(){ ( {m["d
super(); YJuaQxs
} K>RL
S"|D!}@-
/** 'h O+ b
* The constructor using fields z Rz#0
* L
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* @param page |O+R%'z'<
* @param content E5jK}1t4V
*/ /Or76kE
public Result(Page page, List content){ y@~.b^?_u
this.page = page; `y;&M8.
this.content = content; z:+Xs!S
} R{#-IH="
UldK lQ8
/** vW"x)~B
* @return Returns the content. }C/}8<
*/ plsf` a
publicList getContent(){ l2gI2Cioa
return content; L^RyJ;^c
} `*KS`
z?
>/6v`
8F
/**
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* @return Returns the page. uji])e MN~
*/ /#
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public Page getPage(){ 5;`([oX|_
return page; ?TMo6SU
} VEpIAC4
&4O"Xs`ka
/** OMJr.u
* @param content ]
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* The content to set. )09_CC!a
*/ ksu:RJ-
public void setContent(List content){ /iy2j8:z
this.content = content; /J/r 62
} HZ[&ZNTa
twf;{lZ(
/** @*is]d+Ya
* @param page 8Ral%I:gr
* The page to set. ;f?OT7>kN
*/ d^ipf*aLC
publicvoid setPage(Page page){ A
|NX"
this.page = page; OTN"XKa$
} U=Z@Ipu5T
} %04>R'mN
Y
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`"GD'Oa
(cC5zv*E
fN0D\Mu!)b
2. 编写业务逻辑接口,并实现它(UserManager, aR}NAL_`w
m"86O:S#d
UserManagerImpl) BzTm[`(h
java代码: $T;3*D 90
YyK9UZjI
+ZizT.$&
/*Created on 2005-7-15*/ {:4); .
package com.adt.service; fkRb;aIl
<u4GIi
<sm
import net.sf.hibernate.HibernateException; &bBp`h
h=`rZC
import org.flyware.util.page.Page; lba*&j]w=
G`6U t
import com.adt.bo.Result; 3AWB Y.
<Y~V!9(~{Q
/** ]Y;$~qQ
* @author Joa -6+HA9zz@C
*/ pNVao{::5
publicinterface UserManager { G <Lm}
xs.[]>nQN
public Result listUser(Page page)throws kwWO1=ikz@
_AVCh)Zb
HibernateException; I*K^,XY+
*aG0p&n}
} KO{}+~,.6
Kz$Ijj
+Tq
_n@
xU@Z<d,k
#Sn&Wo
java代码: "_?^uymw
S'ikr
7-^df0
/*Created on 2005-7-15*/ <408lm
package com.adt.service.impl;
~ikTo -
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p$K
import java.util.List; P-+ ^YN,
fK4laDBTO
import net.sf.hibernate.HibernateException; >z[d~
lFc3 5
import org.flyware.util.page.Page; }f6.eqBX4
import org.flyware.util.page.PageUtil; !p0FJ].g,
n>#h(
import com.adt.bo.Result; +|#:*GZ
import com.adt.dao.UserDAO; BOh&Db*
import com.adt.exception.ObjectNotFoundException; egr@:5QwZ{
import com.adt.service.UserManager; r>z8DX@
+XY}-
/** dW:
* @author Joa r 9*{)"
*/ XZKOBq B]
publicclass UserManagerImpl implements UserManager { ghms-.:b8
<<UlFE9"
private UserDAO userDAO; k{@z87+&
Ch7eUTqA@
/** AiO,zjM =
* @param userDAO The userDAO to set. i"_f46rP
*/ b~#rUOXb8?
publicvoid setUserDAO(UserDAO userDAO){ hR=4w$
this.userDAO = userDAO; 4SG[_:+!
} 72v 9S T
PN\2 ^@>_
/* (non-Javadoc) j$8~M
* @see com.adt.service.UserManager#listUser Gi{1u}-0
J+.t\R
(org.flyware.util.page.Page) hp>me*vzr
*/ a,}{f]
public Result listUser(Page page)throws @]2cL
8,['q~z
HibernateException, ObjectNotFoundException { BA-n+WCWJ
int totalRecords = userDAO.getUserCount(); d]@9kG
if(totalRecords == 0) 0K#dWc}"a
throw new ObjectNotFoundException iqOd]H]v
rH-_L&
("userNotExist"); kkd<CEz2IM
page = PageUtil.createPage(page, totalRecords); xX|-5cM;
List users = userDAO.getUserByPage(page); Jwa2Y0
returnnew Result(page, users); g$]9xn#_[
} VF[]E0=u6
!PQ@"L)p
} nY~CAo/:
<Ft.{aNq$c
,l@hhaLm?
^8fO3<Jg
T.K$a\/{,
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,u\M7,a^
@Z |cUHo
询,接下来编写UserDAO的代码: JFZZ-t;*
3. UserDAO 和 UserDAOImpl: e@I?ESZ5
java代码: Y$,]~Qzq
QTP1u
<X;y
4lPZ
/*Created on 2005-7-15*/ o9Agx{'oV
package com.adt.dao; */Y@:Sjf
]INbRytvc
import java.util.List; )IhI~,0Nmj
Y@L`XNl
import org.flyware.util.page.Page; HPt"
T>1E
import net.sf.hibernate.HibernateException; Yoaz|7LS
"}ZD-O`!
/** 85H8`YwPh
* @author Joa .e]!i(5I
*/ 3S <5s}
publicinterface UserDAO extends BaseDAO { `FmI?:Cv
6BMRl%3>Z
publicList getUserByName(String name)throws T4Zp5m")
yfaXScbE
HibernateException; UUA7m$F1
m >'o&Hj
publicint getUserCount()throws HibernateException; h#`qEK&u
,AM6E63
publicList getUserByPage(Page page)throws .}z&$:U9[
ph3[}><6
HibernateException; D5U\~'{L
ogQbST
} 4}=]QQoE
thUs%F.5?
MMcHzRF
GJH6b7I
#n0P'@d,r
java代码: `U?;9!|;6
`cf&4Hn
9i9VDk{
/*Created on 2005-7-15*/ D^f;dT;-
package com.adt.dao.impl; fxyPh
lN^L#m*@
import java.util.List; .|_+>){$w
rK"$@tc
import org.flyware.util.page.Page; F
lbL`@4M
JQ0KXS Nr
import net.sf.hibernate.HibernateException; YK_a37E{F
import net.sf.hibernate.Query; Bz]64/
F"9qBl~
import com.adt.dao.UserDAO; :%;K`w
*6=[Hmygi
/** cMtkdIO
* @author Joa +:oHI[1HG
*/ J9>uLz
public class UserDAOImpl extends BaseDAOHibernateImpl }Z%*gfp
\O\onvEa
implements UserDAO { r@iGMJx$
6Zkus20
/* (non-Javadoc) rTK/WZs8
* @see com.adt.dao.UserDAO#getUserByName YY$K;t{dk
6g7 X1C
(java.lang.String) 9 ?h)U|J?G
*/ =Y
/
publicList getUserByName(String name)throws 3hb1^HNT
~|fd=E%
HibernateException { g.&&=T
String querySentence = "FROM user in class |J~;yO SD
>#xpg&2x
com.adt.po.User WHERE user.name=:name"; kOJs;k
Query query = getSession().createQuery GHH1jJ_[7
V,&s$eQC
(querySentence); 6%O"
query.setParameter("name", name); uVIs5IZzIi
return query.list(); 1p`XK";g
} py@5]n%
~
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/* (non-Javadoc) +vJ[k 2d
* @see com.adt.dao.UserDAO#getUserCount() X}g!Lp
*/ a i}8+L8-
publicint getUserCount()throws HibernateException { 0* ,r
int count = 0; z<s]Z
String querySentence = "SELECT count(*) FROM pbju;h)O!|
y{5ZC~Z<!
user in class com.adt.po.User"; orEwP/L:
Query query = getSession().createQuery ?hsOhUs(5
e7 5*84
(querySentence); "y>l2V,4j%
count = ((Integer)query.iterate().next -/KVZ
Fi1gM}>py
()).intValue(); Nluy]h
&
return count; 6g( 2O[n.
} ;^t<LhN:
QH#|R92:
/* (non-Javadoc) @P[Tu; 4
* @see com.adt.dao.UserDAO#getUserByPage qnruatA
1R1J/Z*V/
(org.flyware.util.page.Page) S9-K
*/ E^Q|v45d
publicList getUserByPage(Page page)throws |o=eS&)
W=]QTx,J
HibernateException { G^j/8e
String querySentence = "FROM user in class bL{wCo-Y
-F@Rpfrj_#
com.adt.po.User"; /]iv9e{uh(
Query query = getSession().createQuery Rq9v+Xq2
UiF ?Nx~
(querySentence); Zwp*JH+G
query.setFirstResult(page.getBeginIndex()) V$<og
.setMaxResults(page.getEveryPage()); C$
nT&06o
return query.list(); F8>Fp"
} c,4UnEoCR
EC&w9:R
} uiM*!ge
rhwY5FD?
d%5QEVV
rp.JYz,
FZb\VUmnV
至此,一个完整的分页程序完成。前台的只需要调用 l9?]t;
!,INrl[
userManager.listUser(page)即可得到一个Page对象和结果集对象 ~h tV*R
|"vqM)V$
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y0aO/6
e{c%o;m(
webwork,甚至可以直接在配置文件中指定。 jK3% \`o
Bk~WHg>@G
下面给出一个webwork调用示例: ^|-x mUC
java代码: ,W7\AY07]
X^r HugQ
|oC&;A
/*Created on 2005-6-17*/ xgnt)&7T
package com.adt.action.user; #Ubzh`v
z(K[i?&
import java.util.List; 1k3wBc5<
* t{A=Wk
import org.apache.commons.logging.Log; &*/8Ojv)9
import org.apache.commons.logging.LogFactory; 7AHEzJh"
import org.flyware.util.page.Page; oq(um:m
asmMl9)(`
import com.adt.bo.Result; T6%*t#8r
import com.adt.service.UserService; ko$bCG%
import com.opensymphony.xwork.Action; 9bq#&~+
!+=jD3HTJ
/** ?4(uwXp
* @author Joa a[[u>oHyd
*/ j*rra
publicclass ListUser implementsAction{ UYD(++
Z?O aY4
privatestaticfinal Log logger = LogFactory.getLog 2<
w/GX.
T/dchWG
(ListUser.class); f[!N]*
&tkkn2t
private UserService userService; Z"]
ben
WDWb7
private Page page; `2Ju[P
w*u HB;?
privateList users; 8L9xP'[^
HBV~`0O$
/* p4bQCI
* (non-Javadoc) &5)Kg%r
* srw5&s(3X
* @see com.opensymphony.xwork.Action#execute() <dLdSEw
*/ 0^?(;AK
publicString execute()throwsException{ :p%nQF,*f
Result result = userService.listUser(page); VfAIx]Fa
page = result.getPage(); vZq7U]RW
users = result.getContent(); &d[&8V5S
return SUCCESS; |j#x}8[(
} w%GEOIj}
.3 m^yo
c/
/** ~^w;`~L
* @return Returns the page. L'`W5B@
*/ aM,>LKNbQ
public Page getPage(){ GG/~)^VMe
return page; 0<Vw0%!
} @{j'Pf'
v@&&5J|
/** [^A 93F
* @return Returns the users. yOxJx7uD
*/ ]}<wS]1
publicList getUsers(){ ?tQUZO
return users; /g< T)$2
} JLp.bxx
e(@ YBQ/Z
/** ahU\(=
* @param page !6'j
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* The page to set. OAEJ?ik
*/ 9e@Sx{?r
publicvoid setPage(Page page){ 9\0
this.page = page; 6(f[<V!r
} UW8b(b[-6b
9mIq9rQ|*
/** C6Ap
4
* @param users f5IO<(:E^
* The users to set. .\7R/cP}{A
*/ !rlN|HB
publicvoid setUsers(List users){ rgWGe6;!
this.users = users; & ;ie+/B
} 6!
\a8q'z
r77?s?
/** -4mUGh1dy
* @param userService Q|rrbx b
* The userService to set. D"oyl`q
*/ 3+;]dqZ
publicvoid setUserService(UserService userService){ nzmv>s&UW
this.userService = userService; /0>Cy\eN0
} S^HuQe!#
} L&+XFntR
B8NOPbT
)f>s\T
SWvy<f4<
0%7c?3#
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, V
lN&Lz
]i3 2-8%
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 gmB?L0UV
*IJctYJaX
么只需要: J 6U3}SO=y
java代码: ^|5bK_Z&
9]r6V
P^#<h"Ht
<?xml version="1.0"?> sNZ{OD+
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _V^^%$
UbE*x2N
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 0&E{[~Pv
a938l^@;s8
1.0.dtd"> (0g@Z`r
YQxVeS(
<xwork> \74+ cN
zpx
<package name="user" extends="webwork- ^P
>; %
fn>MOD!l
interceptors"> ,.6Hh'^65^
Rb\M63q
<!-- The default interceptor stack name h1} x2
>y#<WB$i
--> T B~C4H K=
<default-interceptor-ref c7.%Bn,
}A;J-7g6
name="myDefaultWebStack"/> B@D3aOvO
y((I2g1rv
<action name="listUser" Rm`_0}5
N|Mzj|i.
class="com.adt.action.user.ListUser"> HWG5Ghu8,)
<param )<-\ F%&b
(E )@@p7,:
name="page.everyPage">10</param> `j{5$X
<result 9IZ}}x
UmZ#Cm
name="success">/user/user_list.jsp</result> ig3HPlC
</action> Vi[* a
EH<rUv63
</package> eSHyA+F
_"%mLH=!8
</xwork> TC;2K,.#k
,rx?Ig}kz
gTcLS|&