Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }@Lbvaa
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 CJ0j2e/
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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 '|Dm\cy
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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 bSsX)wHm
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。 ?XO$9J
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分页支持类: "&Ym(P
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java代码: {` Bgxejf
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package com.javaeye.common.util; &>43l+
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import java.util.List; +ou5cQ^
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publicclass PaginationSupport { "MZj}}l
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publicfinalstaticint PAGESIZE = 30; .n1]Yk;,1
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privateint pageSize = PAGESIZE; 1^rODfY 0
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privateList items; ?zp@HSa9
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privateint totalCount; :c%vl$
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privateint[] indexes = newint[0]; _D7MJT
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privateint startIndex = 0; wZN<Og+;
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public PaginationSupport(List items, int j4RM'_*G
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totalCount){ \Ku6gEy
setPageSize(PAGESIZE); "P;_-i9O
setTotalCount(totalCount); KIO{6
setItems(items); ,p6X3zY
setStartIndex(0); [X[d`@rXv
} kr2V
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public PaginationSupport(List items, int ~$} `R=
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totalCount, int startIndex){ W_(
setPageSize(PAGESIZE); OLpE0gZ.|`
setTotalCount(totalCount); v`8dRVN
setItems(items); y)_T!&ze
setStartIndex(startIndex); Pda(O;aNU
} F3[3~r
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public PaginationSupport(List items, int vhiP8DQ
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totalCount, int pageSize, int startIndex){ f.rc~UI?
setPageSize(pageSize); O.4ty)*
setTotalCount(totalCount); (m|w&oA/
setItems(items); SAswP
setStartIndex(startIndex); H@Dj$U
} ;,GE!9HW
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publicList getItems(){ eED Fm
return items; aV`4M VWOz
} .lm^ +1}r
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publicvoid setItems(List items){ odAeBQy
this.items = items; QU0K'4Yx5j
} GGHe{l
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publicint getPageSize(){ w8i"-SE
return pageSize; ':6!f
} Vh1{8'GQ
fnV^&`BB
publicvoid setPageSize(int pageSize){ 16=tHo8|
this.pageSize = pageSize; qXO@FW]
} \P% E1c#
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publicint getTotalCount(){ gd3~R+Kd
return totalCount; `ro~l_U;A
} ~ldqg2c
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publicvoid setTotalCount(int totalCount){ v#i,pBj
if(totalCount > 0){ ]F
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this.totalCount = totalCount; #xZ7%
int count = totalCount / 'ms&ty*T
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pageSize; apQ` l^
if(totalCount % pageSize > 0) 7A@GNA
count++; 0X =Yly*m@
indexes = newint[count]; C8i6ESmU
for(int i = 0; i < count; i++){ 1B+uv0lA
indexes = pageSize * q]+'{Ci@
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i; @KRr$k
} .T0w2Dv/
}else{ Stqlp<xy
this.totalCount = 0; "i/ l'
} Oi#F
} 2:0'fNXop
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publicint[] getIndexes(){ )Cl!, m)~
return indexes; :db:|=#T
} k@r%>Ul@
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publicvoid setIndexes(int[] indexes){ FWpcWmS`s
this.indexes = indexes; m":lKXpQ
} o>lk+Q#L @
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publicint getStartIndex(){ :[f2iZ"
return startIndex; wRu+:<o^.
} R5=2EwrGP
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publicvoid setStartIndex(int startIndex){ sCG[gshq
if(totalCount <= 0) 5*QNE!
this.startIndex = 0; w yi n
elseif(startIndex >= totalCount) _(=[d
this.startIndex = indexes w_o|k&~,
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[indexes.length - 1]; 3B| ?{U~
elseif(startIndex < 0) s"5f5Cn/Wh
this.startIndex = 0; Xk=bb267
else{ ]A)`I
this.startIndex = indexes kGbtZ} W
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[startIndex / pageSize]; ,{=pFs2
} c zTr_>
} zFVNb
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publicint getNextIndex(){ ()L[l@m
int nextIndex = getStartIndex() + [:Kl0m7
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pageSize; 7,Tg>,%Q
if(nextIndex >= totalCount) %\OG#36
return getStartIndex(); }c/p+Wo
else Uz(Sv:G
return nextIndex; wxw3t@%mNm
} hxcRFqX"
9 -7.4!]I
publicint getPreviousIndex(){ IK~'ke
int previousIndex = getStartIndex() - !bEy~.
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pageSize; -90qG"@
if(previousIndex < 0) 0N02 E
return0; D|`O8o?)
else !Yuu~|
return previousIndex; Ubtu?wRBW
} n^Co
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} ?V6A:8t,
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抽象业务类 $-4OveS~B
java代码: v5J%
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/** ]:Y@pZ
* Created on 2005-7-12 (.6~t<DRv
*/ Z!\xVCG"q
package com.javaeye.common.business; 8}9B*m
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import java.io.Serializable; ')!+>b(P
import java.util.List; \KmgFyF
tuZA q;X
import org.hibernate.Criteria; }O=QXIF5
import org.hibernate.HibernateException; u#TRm?s
import org.hibernate.Session; v/ dyu
import org.hibernate.criterion.DetachedCriteria; ~fL:pVp
import org.hibernate.criterion.Projections; (J!FW(Ma|=
import Mf [v 7\
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org.springframework.orm.hibernate3.HibernateCallback; uCX+Lw+As
import Skm$:`u;
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org.springframework.orm.hibernate3.support.HibernateDaoS rof&O
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upport; y*i_Ec\h
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import com.javaeye.common.util.PaginationSupport; GTvp)^h
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public abstract class AbstractManager extends >eF4YZ"
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HibernateDaoSupport { :)/%*<vq,
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privateboolean cacheQueries = false; QL_~E;U
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privateString queryCacheRegion; '<(S*&s
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publicvoid setCacheQueries(boolean ^;on
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cacheQueries){ E:EXp7
this.cacheQueries = cacheQueries; U%E6"Hg
} ZHA6BVVT
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publicvoid setQueryCacheRegion(String oH;0_!
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queryCacheRegion){ >MXE)=
this.queryCacheRegion = irqNnnMGEa
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queryCacheRegion; l`#XB:#U
} x2@Q5|a
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publicvoid save(finalObject entity){ ^F5Q(A
getHibernateTemplate().save(entity); 4Ji6B)B
} ym>>5 (bni
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publicvoid persist(finalObject entity){ QfLDyJv`e
getHibernateTemplate().save(entity); iw`,\V&
} !8cS1(a
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publicvoid update(finalObject entity){ <IiX_*
getHibernateTemplate().update(entity); f 7g?{M
} '|v??`o#
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publicvoid delete(finalObject entity){ tS$^k)ZXip
getHibernateTemplate().delete(entity); O\=U'6@
} pn},o vR;
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publicObject load(finalClass entity, /FzO9'kj
*rs@6BSj
finalSerializable id){ u9 LP=g
return getHibernateTemplate().load xG802?2i/;
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(entity, id); Y[oNg>Rz
} {9yv3[f3
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publicObject get(finalClass entity, 'QR
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finalSerializable id){ ".n,R"EF
return getHibernateTemplate().get fpCkT [&m
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(entity, id); &&(^;+
} 3<5E254N
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publicList findAll(finalClass entity){ *aE/\b
return getHibernateTemplate().find("from Y)X
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vr /O%mDp
" + entity.getName()); RyI(6TZl
} Gp0B^^H$
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publicList findByNamedQuery(finalString AKKp-I5
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namedQuery){ --(e(tvf
return getHibernateTemplate jgcI|?yL
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().findByNamedQuery(namedQuery); 6qCRM *V
} .@#GNZe
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publicList findByNamedQuery(finalString query, -vRZCIj!
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finalObject parameter){ `s0`kp
return getHibernateTemplate RW4}n<
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().findByNamedQuery(query, parameter); 3LxhQVx2
} (?9 @nS
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publicList findByNamedQuery(finalString query, Z6.0X{6nA
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finalObject[] parameters){ a>3#z2#
return getHibernateTemplate O
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().findByNamedQuery(query, parameters); ;WF3w
} 0^5*@vt
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publicList find(finalString query){ utH,pGs C.
return getHibernateTemplate().find 0E6>PE;
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(query);
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} {8!\aYI
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publicList find(finalString query, finalObject ~1_v;LhH5+
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parameter){ Dz<"eyB\
return getHibernateTemplate().find ;y"=3-=vM"
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(query, parameter); =Nyq1~
} j_3X
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public PaginationSupport findPageByCriteria ,KT[ }P7
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria my.%zF
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \Zpg,KOT
} 2Hh5gD|>
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public PaginationSupport findPageByCriteria j %3wD2 l
*B$$6'hi`
(final DetachedCriteria detachedCriteria, finalint 91|0{1
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startIndex){ 'Gr}<B$A3
return findPageByCriteria Q+Sx5JUR~
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(detachedCriteria, PaginationSupport.PAGESIZE, OoG Nij
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startIndex); 2 Nr*
} &d!Q%
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public PaginationSupport findPageByCriteria 4#dS.UfI
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(final DetachedCriteria detachedCriteria, finalint _4Ciai2Ql
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pageSize, vr:5+wew
finalint startIndex){ .B9i`)0
return(PaginationSupport) ;ui=7[Us
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getHibernateTemplate().execute(new HibernateCallback(){ R#K,/b%SV
publicObject doInHibernate C0RnBu
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(Session session)throws HibernateException { p3Ey[kURp
Criteria criteria = z 2/E?$(
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detachedCriteria.getExecutableCriteria(session); dKG 2f
int totalCount = lRy^Wp
/=+y[y3`
((Integer) criteria.setProjection(Projections.rowCount 4!l%@R>O2
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()).uniqueResult()).intValue(); =!?4$vW
criteria.setProjection j\/Rjn+:[
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(null); rV5QKz6'
List items = "\CUHr9k
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criteria.setFirstResult(startIndex).setMaxResults PQ}owEJ2eM
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(pageSize).list(); rAuv`.qEV
PaginationSupport ps = r_p4pxs
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new PaginationSupport(items, totalCount, pageSize, 7uI~Xo?N
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startIndex); W%&[gDp
return ps; 0q !
} ?'jRUf l
}, true); s)eU^4m
} n
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public List findAllByCriteria(final 3-%F)@n
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DetachedCriteria detachedCriteria){ Z%_m<Nf8T
return(List) getHibernateTemplate $K'A_G^
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().execute(new HibernateCallback(){ @i9eH8lT
publicObject doInHibernate 8-"lK7
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(Session session)throws HibernateException { #P^cR_|\
Criteria criteria = &3_S+.JO
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detachedCriteria.getExecutableCriteria(session); Z~s"=kF,
return criteria.list(); W "}Cfv
} ?h1r6?Sug{
}, true); &Bc$8ZR
} m})EYs1
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public int getCountByCriteria(final Jh6 z5xUV
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DetachedCriteria detachedCriteria){ Y6R+i0guz
Integer count = (Integer) U~nW>WJ+.
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getHibernateTemplate().execute(new HibernateCallback(){ $={^':Uh
publicObject doInHibernate :'+- %xUM
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(Session session)throws HibernateException { [ELg:f3}5
Criteria criteria = NZaMF.
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detachedCriteria.getExecutableCriteria(session); UbDRE[^P
return $HE ?B{
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criteria.setProjection(Projections.rowCount o'hwyXy/S
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()).uniqueResult(); ky^u.+cZ
} ]y52%RAKI
}, true); '(S@9%,aK1
return count.intValue(); H\[:uUK5\
} ^j)0&}fB
} Gd:fh5u':
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用户在web层构造查询条件detachedCriteria,和可选的 .~L^h/)Gjy
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 08pG)_L
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PaginationSupport的实例ps。 O.+02C_*
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ps.getItems()得到已分页好的结果集 ?yq $
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ps.getIndexes()得到分页索引的数组 YS|Ve*t(L=
ps.getTotalCount()得到总结果数 wFHz<i!jr&
ps.getStartIndex()当前分页索引 ta)'z@V @g
ps.getNextIndex()下一页索引 !}$,) ~<+H
ps.getPreviousIndex()上一页索引 oDvE0"Sz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 017(I:V?(:
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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 uz8Y)b
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一下代码重构了。 )c"m:3D@
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我把原本我的做法也提供出来供大家讨论吧: /"LcW"2;N
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首先,为了实现分页查询,我封装了一个Page类: }.$5'VGO
java代码: +_E\Omcw
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/*Created on 2005-4-14*/ }1)tALA
package org.flyware.util.page; (='e9H!3D
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/** qx+ .v2G
* @author Joa w]ZE('3%W
* QT\=>,Fz _
*/ 'U8% !
publicclass Page { UW?(-_8
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/** imply if the page has previous page */ F#S)))#
privateboolean hasPrePage; Munal=wL
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/** imply if the page has next page */ Dno'-{-
privateboolean hasNextPage; m+ww
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/** the number of every page */ 2xx
privateint everyPage; ]LE
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/** the total page number */ %JsCw8C6?
privateint totalPage; %9qG|A,cA
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/** the number of current page */ 0OrT{jo
privateint currentPage; tU :,s^E"#
*t-Wol
/** the begin index of the records by the current 6S2u%-]
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query */ *NEA(9
privateint beginIndex; !jIpgs5
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/** The default constructor */ c@]_V
public Page(){ P0 va=H
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} l?AWG&
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/** construct the page by everyPage 4.^1D';(
* @param everyPage A{3?G-]*
* */ EC]b]'._
public Page(int everyPage){ J!5>8I(_wX
this.everyPage = everyPage; >\x
} E`DsRR <
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/** The whole constructor */ '|9fDzW"]
public Page(boolean hasPrePage, boolean hasNextPage, <H,q( :pM
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&f:"p*=a\
int everyPage, int totalPage, has \W\(
int currentPage, int beginIndex){ k6pXc<]8
this.hasPrePage = hasPrePage; 2GHmA_7P
this.hasNextPage = hasNextPage; :ziV3jRM
this.everyPage = everyPage; w,<nH:~
this.totalPage = totalPage; -j6&W`
this.currentPage = currentPage; |BO!q9633V
this.beginIndex = beginIndex; 4}4K6y<q
} t81}jD
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/** #K5)Rb-H
* @return P{'T9U|O-
* Returns the beginIndex. >A+0"5+_p
*/ aWG7k#nE
publicint getBeginIndex(){ z^KMYvH
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return beginIndex; h7}D//~p
} f:=y)+@1My
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/** U^ecg{
* @param beginIndex E% ?X-$a
* The beginIndex to set. 3XCePA5z
*/ 8:x{
publicvoid setBeginIndex(int beginIndex){ ':}
this.beginIndex = beginIndex; zNu>25/)(
} 4H<@da}
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/** yBd#*3K1
* @return 0gI^GJN%Y!
* Returns the currentPage. Z'vic#
*/ ({GN.pC(
publicint getCurrentPage(){ l"I
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return currentPage; 9]{(~=D7
} , ;'y <GA
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/** %Km^_JM
* @param currentPage oVG/[e|c'
* The currentPage to set. o@&Hc bN^
*/ 5#DtaVz
publicvoid setCurrentPage(int currentPage){ b6@(UneVM
this.currentPage = currentPage; <B
}4}-}
}
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/** r#%e$
* @return dB{VY+!
* Returns the everyPage. 7S
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*/ f1hjU~nJ
publicint getEveryPage(){ r )EuH.z
return everyPage; kM#ZpI&0%
} 7Fg-}lJAC
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/** 3gUGfedi
* @param everyPage }m`+E+T4
* The everyPage to set. a2'si}'3
*/ 0q@U>#
publicvoid setEveryPage(int everyPage){ }i)^?@
this.everyPage = everyPage; h#Z5vH
} ]*M VVzF
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/** "@!B"'xg
* @return da'7*
&/
* Returns the hasNextPage. dbmty|d
*/ 1 2Lc$\3P
publicboolean getHasNextPage(){ MPexc5_
return hasNextPage; YH:murJMZ
} hC nqe
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/** ~h:/9q
* @param hasNextPage _ ?\4k{ET
* The hasNextPage to set. rA"><pH
*/ |JR;E$
publicvoid setHasNextPage(boolean hasNextPage){ jkN-(v(T
this.hasNextPage = hasNextPage; /+11`B09
} )\!-n]+A
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/** 9b8kRz[ c
* @return .y)Y20=o!
* Returns the hasPrePage. voD0u
*/ !%1=|PX_
publicboolean getHasPrePage(){ 'QMvj` -
return hasPrePage; |x
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} NIzxSGk|
P ]prrKZe,
/** ftw@ nQNU
* @param hasPrePage aCwb[7N
* The hasPrePage to set. 09r0Rb
*/ jOE~?{8m
publicvoid setHasPrePage(boolean hasPrePage){ `X =2Ff
this.hasPrePage = hasPrePage; !6d6b@Mv
} 1z#0CX}Y/H
/.Fvl;!J;
/** ,pg\5b
* @return Returns the totalPage. jgkJF[t`
* #Q6.r.3@x
*/ a9w1Z4
publicint getTotalPage(){ w<4,;FFlZ/
return totalPage; t!u{sr{j=
} nJ ZQRRa:C
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/** ,^>WCG
* @param totalPage q3~RK[OCq
* The totalPage to set. {e3XmVAI
*/ >o#^)LN
publicvoid setTotalPage(int totalPage){ ~kkwPs2V
this.totalPage = totalPage; Z,? T`[4B
} --32kuF&(
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} L,
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 }IRx$cKV
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个PageUtil,负责对Page对象进行构造: +(*;F4>
java代码: itp$c|{
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/*Created on 2005-4-14*/ Rzolue 8
package org.flyware.util.page; ,%L>TD'48s
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import org.apache.commons.logging.Log; N@z+h
import org.apache.commons.logging.LogFactory; T9N&Nh7 3
Ao%;!(\I%
/** Yy_o*Ozq
* @author Joa z@_9.n]
* xz#.3|_('
*/ +&T;jad2
publicclass PageUtil { j.5;0b_L^
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privatestaticfinal Log logger = LogFactory.getLog RZV8{
@aA1=9-L
(PageUtil.class); -quWnn/
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/** XO=UKk+EK
* Use the origin page to create a new page R
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* @param page @rTAbEk{U
* @param totalRecords jMT];%$[
* @return 6L2Si4OGjG
*/ *@C4~Zo
publicstatic Page createPage(Page page, int N1O& fMz
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totalRecords){ Rilr)$
return createPage(page.getEveryPage(), 9O%4x"*PO
) ny,vcU]
page.getCurrentPage(), totalRecords); LGOeBEAMV^
} &SzLEbU!
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/** /eoS$q
* the basic page utils not including exception #2F 6}
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handler m-~eCFc
* @param everyPage (f5v{S6b(
* @param currentPage e|L$e0
* @param totalRecords S[J=d%(
* @return page }x[d]fcC
*/ *L%i-Wg"
publicstatic Page createPage(int everyPage, int B>^5h?(lt
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currentPage, int totalRecords){ eBK s-2r
everyPage = getEveryPage(everyPage); 4E Hb
currentPage = getCurrentPage(currentPage); t*fG;YOg
int beginIndex = getBeginIndex(everyPage, +3c!.] o;
")q{>tV
currentPage); pearf2F
int totalPage = getTotalPage(everyPage, >};6>)0
"hRY+{m
totalRecords); YzcuS/~x
boolean hasNextPage = hasNextPage(currentPage, :qx>P_&y}z
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totalPage); [7gyF}*;
boolean hasPrePage = hasPrePage(currentPage); IZm_/
iw Hy!Vi-5
returnnew Page(hasPrePage, hasNextPage, _HT*>-B
everyPage, totalPage, 0I.9m[<Fc
currentPage, /nK)esB1L
bw@DcT&,
beginIndex); qM`XF32A$
} sP0pw]!
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privatestaticint getEveryPage(int everyPage){ hIj[#M&6
return everyPage == 0 ? 10 : everyPage; pai>6p
} 2$D
*~~
WC!b B
privatestaticint getCurrentPage(int currentPage){ Y$^x.^dT,
return currentPage == 0 ? 1 : currentPage; 3:$hC8
} &`a$n2ycy
4>4*4!KR}
privatestaticint getBeginIndex(int everyPage, int :<%q9)aPf`
AgsMk
currentPage){ DPfP)J:~
return(currentPage - 1) * everyPage; r9Ux=W\
} 2Yx6.e<
bQ-5uFe~$B
privatestaticint getTotalPage(int everyPage, int mMqT-jT
rK*s/mX <
totalRecords){ ^4LkKYMS
int totalPage = 0; xMsos?5}
Sf}>~z2
if(totalRecords % everyPage == 0) BoB2q(
totalPage = totalRecords / everyPage; 9.|+KIRb
else NF1e>O:a<
totalPage = totalRecords / everyPage + 1 ; y2V9!
\?[#>L4
return totalPage; JMu|$"o&{
} @18"o"c7j
8T'=lTJ
privatestaticboolean hasPrePage(int currentPage){ j380=?7
return currentPage == 1 ? false : true; cL&V2I5O
} %T*lcg
omM*h{z$$
privatestaticboolean hasNextPage(int currentPage, buo_H@@p{s
rt%.IQdY
int totalPage){ *b?C%a9
return currentPage == totalPage || totalPage == uROt h_/
tRYMK+
0 ? false : true; >9W ;u`
} YzU(U_g$
;YxQo
o>
v*5n$UFV
} W|@EK E.k
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un
.+7GecYz
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 (LPMEQhI:
2Z6#3~
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 lIO.LF3
R2Fh
WiL
做法如下: [7?K9r\#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ll{jE
]#N2:ych
的信息,和一个结果集List: 9|T%q2O
java代码: nMD^x
ahkSEE{
~oI7TP
/*Created on 2005-6-13*/ Vb06z3"r
package com.adt.bo; T#^
~#iRh6^98
import java.util.List; KzZ!
CB\
>2`)S{pBD
import org.flyware.util.page.Page; ^~(vP:
K1Nhz'^=D
/** .]%PnJM9K
* @author Joa T[s_w-<7$
*/ .MuS"R{y
publicclass Result { } ab@Nd$
PygT_-3z{
private Page page; $78fR8|r-
PJN TIa
private List content; +ex@[grsGT
Mn $TWhg'
/** aQwc Py|1R
* The default constructor bC?uyo"
*/ +Y,>ftN
public Result(){ d8Jy$,/`?
super(); .pQH>;k]K
} ?:Y{c#w>
}pj>BK>
/** elb|=J`M0
* The constructor using fields ?U~C= F?K
* 8Wid.o-U
* @param page Ix g.^>62
* @param content KDgJ~T
*/ F{ J>=TC
public Result(Page page, List content){ X>2_Gol!
this.page = page; B;[{7J]
this.content = content; ?ltTJ(Po
}
bLGgu#
r#*kx# "
/** U?JZ23>bbw
* @return Returns the content. >-
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*/ kVw5z3]Xg
publicList getContent(){ ]uX'[Z}t
return content; q=ZLSBZ
} 2V_C_5)1
Y$!K<c k
/** =v=a:e
* @return Returns the page. t>f<4~%MJ
*/ I\PhgFt@O
public Page getPage(){ |r 1\
return page; n[lf==R
} Qn(e[
C6\
C_=! ( @`8
/** BKfcK>%g
* @param content |E0>-\6
* The content to set. gxpR#/(E~
*/ jZS6f*$
public void setContent(List content){ s;X"E=
this.content = content; !!4_x
} dON4r2-yC
5j1}?0v_
/** ii0AhQ
* @param page q$e2x=?
* The page to set. EcrM`E#kaZ
*/ ,x!P|\w.G{
publicvoid setPage(Page page){ [sp=nG7i&
this.page = page; Rv
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} q.FgX
} &Eg>[gAIlp
n|IdEgD$
~"!F&
6c>t|=Ss(
1HL}tG?+#
2. 编写业务逻辑接口,并实现它(UserManager, U|6 ME%xm
Sx+.<]t2A
UserManagerImpl) \ }>1$kH;
java代码: XWZ
*{/u
"2(lgxhj
ym:^Y-^iV
/*Created on 2005-7-15*/ k1i*1Tc
package com.adt.service; DtG><g}[]
|1X^@
import net.sf.hibernate.HibernateException; ~Y@(
e4u$+
import org.flyware.util.page.Page; qCOv4b`
YUJlQ2e(
import com.adt.bo.Result; {co(w
7
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_0
/** ZdeRLX
* @author Joa j':Ybr>BR
*/ S*Un$ngAh
publicinterface UserManager { yd[}?
D{I^_~-\5
public Result listUser(Page page)throws lidzs<W-fW
xekW-=#a7-
HibernateException; S:/;|Dg
}MW*xtGV
} KG6ki_
RzQ1Wq
sy+1xnz
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`DIIJ<;g
java代码: Mz#
&"WjF
7'Y 3T[
Fx2
KRxk
/*Created on 2005-7-15*/ SLpB$puS
package com.adt.service.impl; SdBv?`u|g
?Q[uIQ?dV
import java.util.List; z8{ kwz
N~_GJw@
import net.sf.hibernate.HibernateException; xK 9"t;!C&
))|Wm}
import org.flyware.util.page.Page; F7gipCc1We
import org.flyware.util.page.PageUtil; TKj8a(R_
I8@NQ=UV0
import com.adt.bo.Result; F& .iY0Pt
import com.adt.dao.UserDAO; I!&|L0Qq
import com.adt.exception.ObjectNotFoundException; r-v;A
import com.adt.service.UserManager; <8yzBp4gZ
uQazUFw
/** K)~ m{
* @author Joa *,5V;7OR
*/ V.#,dDC@j
publicclass UserManagerImpl implements UserManager { ewg&DBbN"
.^j#gE&B
private UserDAO userDAO; A9\m.3jo
EGL1[7It`
/** >B/ jTn5=
* @param userDAO The userDAO to set. }Iz'#I
Xx
*/ NH$%g\GPs
publicvoid setUserDAO(UserDAO userDAO){ YMOy6C
this.userDAO = userDAO; #\KSv
Z
} hX?L/yf
Y~EKMowI&e
/* (non-Javadoc) a5ZU"6Hi
* @see com.adt.service.UserManager#listUser x4fl=
B?9K! c
(org.flyware.util.page.Page) Fj}|uiOQUS
*/ s `fIeP
public Result listUser(Page page)throws __r]@hY
Ac;rMwXk#
HibernateException, ObjectNotFoundException { ;> **+ezF
int totalRecords = userDAO.getUserCount(); fH~InDT^
if(totalRecords == 0) )j(13faW|
throw new ObjectNotFoundException X{zg-k(@
:=vB|Ch:~
("userNotExist"); 3kFSu
page = PageUtil.createPage(page, totalRecords); ',j'Hf
List users = userDAO.getUserByPage(page); S'M=P_-7
returnnew Result(page, users); jV
Yt=j*"V
} RB<LZHZI
>yFEUD:
} g.OBh_j-v
:acnrW>i[@
AujvKQ(
sPY*2B
4q#6.E;yy
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 U">J$M@
p6m](Jg
询,接下来编写UserDAO的代码: 4]9+
3. UserDAO 和 UserDAOImpl: TxAT ))
java代码: >!O3 jb k
pFi.?|6"
:q=u+h_
/*Created on 2005-7-15*/ F{}mlQg
package com.adt.dao; PmOm>
JwWW w1
import java.util.List; L4`bGZl55
Poy ]5:.
import org.flyware.util.page.Page; <>$`vuU
$3>k/*=
import net.sf.hibernate.HibernateException; ^$qr6+
Pk/{~!+
$
/** ETvn$ Jdp
* @author Joa -=BQVJ_dK{
*/ lx*"Pj9hho
publicinterface UserDAO extends BaseDAO { Cj31>k1
yO Ed8
publicList getUserByName(String name)throws ']1\nJP[=X
vQB;a?)o
HibernateException; *sK")Q4N
j`jF{k b
publicint getUserCount()throws HibernateException; .),ql_sXr
i zJa`K
publicList getUserByPage(Page page)throws rFJ(t7\9h
%^){Z,}M}
HibernateException; *,qW9z
I;iJa@HWQ
} =" Q5Z6W
I^|6gaP|6
1SIhW:C
,ErJUv
t.wB\Kmt\
java代码: j8WMGSrrF
:m*r(i3
u,AZMjlF
/*Created on 2005-7-15*/ 1_JtD|Jy
package com.adt.dao.impl; ^q``f%Xt
b37F;"G
import java.util.List; dIk/vg
;Zfglid
import org.flyware.util.page.Page; bxX[$q
_SU%ul
import net.sf.hibernate.HibernateException; UeNa
import net.sf.hibernate.Query; hE.NW
\uxDMKy
import com.adt.dao.UserDAO; 7_t\wmvYp
i}SJ
/** ?kBi9^)N4
* @author Joa 7/*Q?ic
*/ v:otR%yt
public class UserDAOImpl extends BaseDAOHibernateImpl
N7%iz+
>y&Db
implements UserDAO { s;oDwT1
bvyX(^I[q
/* (non-Javadoc) r9!jIkILz
* @see com.adt.dao.UserDAO#getUserByName {#>>dILPr
r![RRa^
(java.lang.String) EOqvu=$6
*/ k.Tu#7
publicList getUserByName(String name)throws 3GMRH;/w
a<AT;Tc
HibernateException { ;3ZHm*xJx
String querySentence = "FROM user in class z"4UObVs
i3C5"\y
com.adt.po.User WHERE user.name=:name"; X\X*-.]{
Query query = getSession().createQuery `[T|Ck5
|e+8Xz1>
(querySentence); (r8Rb*OP
query.setParameter("name", name); 63hOK
return query.list(); WzM9{c
} M%dJqwH5{
F$TNYZ
/* (non-Javadoc) H|a9};pO\
* @see com.adt.dao.UserDAO#getUserCount() !>$tRW?gH~
*/ \@yx;}bdI
publicint getUserCount()throws HibernateException { ]{->/.oB
int count = 0; 3GEI) !
String querySentence = "SELECT count(*) FROM h.\V;6ly
\^<eJfD
user in class com.adt.po.User"; ')pXQ
Query query = getSession().createQuery PoyY}Ra
>;@ _TAF
(querySentence); 9qIdwDRY
count = ((Integer)query.iterate().next oqzx}?0
w+ZeVZv!r
()).intValue(); #{973~uj
return count; [kf$82
} SrMg=a
uyr56
/* (non-Javadoc) <uGc=Du
* @see com.adt.dao.UserDAO#getUserByPage Jv
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sKF
(org.flyware.util.page.Page) =rBNEd
*/ YGy.39@31
publicList getUserByPage(Page page)throws \!HGkmd
6FMW}*6<
HibernateException { $~M#msK9
String querySentence = "FROM user in class Xo[={2_
NABwtx>.
com.adt.po.User"; ?C#=Q6
Query query = getSession().createQuery '~?\NeO=
5a
moK7
(querySentence); _tE`W96J
query.setFirstResult(page.getBeginIndex()) n(-1vN
.setMaxResults(page.getEveryPage()); 0pP;[7k\
return query.list(); s;-(dQ{O
} 02Z>#AE
?#|Y'%a"
} NFT&\6!o
ha6jbni
h
WvQh
^6=y4t=%F
p|Po##E}g^
至此,一个完整的分页程序完成。前台的只需要调用 6 /8?:
wfH#E2+pk
userManager.listUser(page)即可得到一个Page对象和结果集对象 .
IBy'
__Kn 1H{
的综合体,而传入的参数page对象则可以由前台传入,如果用 b(8#*S!U
_hgu:
webwork,甚至可以直接在配置文件中指定。 rwb7>]UI"d
0Da9,&D
下面给出一个webwork调用示例: ^O_E
T$
java代码: m,i@
Q/EHvb]
m[~fT(NI
/*Created on 2005-6-17*/ .W_'6Q+
package com.adt.action.user; s!*m^zx
qV^Z@N+,
import java.util.List; x9UF
v8Ga@*
import org.apache.commons.logging.Log; j2A
Z.s
import org.apache.commons.logging.LogFactory; eH.~c3o
import org.flyware.util.page.Page; .(T*mk*>
NRU&GCVwu
import com.adt.bo.Result; H+UA
import com.adt.service.UserService; 1n+C'P"
import com.opensymphony.xwork.Action; SJ(<u2J]
(~6oA f
/** S>AM?
* @author Joa 5U[m]W=B
*/ @LQe[`
publicclass ListUser implementsAction{ Z_iVOctP
7noxUGmFw
privatestaticfinal Log logger = LogFactory.getLog <Co\?h/<
u-yVc*<,
(ListUser.class); E0 ~\ A;
`_`\jd@
private UserService userService; s,&tD
WU
y7a84)j3
private Page page; WCf?_\cG
|Nx7jGd:i
privateList users; /_yJ;l/K
>NL4&MV:
/* ;JQ:S~K9
* (non-Javadoc) ces|HPBa&6
* Ct-^-XD
* @see com.opensymphony.xwork.Action#execute() 9 b?Nlk8d
*/ 6|h~pH
publicString execute()throwsException{ Y
6B7qp
Result result = userService.listUser(page); 1DzI@c~X
page = result.getPage(); IrIF 853g
users = result.getContent(); F#<$yUf%
return SUCCESS; /XfE6SBz
} Pra,r9h,
}q-* Ls~
/** t|/{oAj
* @return Returns the page. B4 XN
*/ NT3Ti
?J,
public Page getPage(){ x^ 0MEsR
return page; 1?!z<<
} <G+IbUG:
]Ak/:pu
/** C71\9K*X
* @return Returns the users. Aw7oyC!
*/ !:zWhu,
publicList getUsers(){ m+3U[KKvG
return users; A9:dHOmT^U
} d z-
e#R'_}\yj
/** oZ
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* @param page XkGS3EY
* The page to set. ()[j<KX{.
*/ ke~S[bL%-
publicvoid setPage(Page page){ n#\ t_/\
this.page = page; =.<S3?
} T^b62j'b5_
=&9x}4`;%
/** DrY5Q&S
* @param users B '@a36
* The users to set. j$%uip{
*/ q3SYlL'a
publicvoid setUsers(List users){ q-k~L\Ys
this.users = users;
B#Q=Fo 6
} ,sk0){rW
<"}Gvi
/** (hb\1wZ
* @param userService ~[wh
* The userService to set. U"0Ts!CABA
*/ s\Zp/-Q
publicvoid setUserService(UserService userService){ 3Mlwq'pzD
this.userService = userService; ea\b7a*
} cD!yd^QE
} "&@v[O)!xu
`3QAXDWE
d^.@~
<}vult^
uyfH;9L5$
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, uFXu9f+
Z:e|~#
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 h^`!kp
Mu~DB:Y9e
么只需要: N8-!}\,
java代码: CnvM>]
?)2&LVrf
+OTNn@!9
<?xml version="1.0"?> .=u8`,sO
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork FK:Tni
/HiRbwQK#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <hvVh9
J8>8@m6
1.0.dtd"> K9@F1ccQ/
u\uY q
<xwork> >E:V7Fa
"T?hIX/p_
<package name="user" extends="webwork- =Ll:Ba Q
"F.0(<4)
interceptors"> ahnQq9
!-OPzfHrI
<!-- The default interceptor stack name jH4'jB
U,_jb}$Sq7
--> 3EHn}#+U
<default-interceptor-ref %`F&,!d
x U1](O
name="myDefaultWebStack"/> lls-Nir%
(oKrIm
<action name="listUser" x9NcIa9
];n3H~2
class="com.adt.action.user.ListUser"> (C=.&',P
<param HLa3lUo
y!,Ly_x$@
name="page.everyPage">10</param>
D ^Cpgha
<result wk'12r6=(-
B_u1FWc
name="success">/user/user_list.jsp</result> !MNnau%O
</action> :|P[u+v
G';yb^DB
</package> `wzb}"gLsM
&YU;
K&
</xwork> Ac'0
2c
Pd$j
U<