Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `zf,$67>1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 j}P
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 p@B/S(Xi
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 k55s-%Ayr
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分页支持类: )y~FeKh
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java代码: ^:krfXT
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package com.javaeye.common.util; ~rnbuIh
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import java.util.List; _xKu EU}
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publicclass PaginationSupport { TRLz>m Q
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publicfinalstaticint PAGESIZE = 30; pJg'$iR!/
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privateint pageSize = PAGESIZE; c<k=8P
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privateList items; 8m prK`p
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privateint totalCount; iX&eQ{LB
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privateint[] indexes = newint[0]; k<&zVV'
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privateint startIndex = 0; UO1WtQyu,H
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public PaginationSupport(List items, int @PQ%
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totalCount){ L'Yg$9 Vz
setPageSize(PAGESIZE); mp'Z.4
setTotalCount(totalCount); (^{tu89ab
setItems(items); |>Ld'\i8
setStartIndex(0); &g;&=<#I
} *XU2%"Sc
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public PaginationSupport(List items, int ^@V;`jsll
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totalCount, int startIndex){ &g.do?
setPageSize(PAGESIZE); jW8,}Xs
setTotalCount(totalCount); = :/4)
setItems(items); ,<CFjtelO
setStartIndex(startIndex); SzTa[tJ+
} MwuRxeRO-
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public PaginationSupport(List items, int GXnrVI
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totalCount, int pageSize, int startIndex){ QomihQnc
setPageSize(pageSize); tH)fu%:p
setTotalCount(totalCount); e0$.|+
setItems(items); p9y@5z
setStartIndex(startIndex); kf:Nub+h t
} z 0}JiW R
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publicList getItems(){ %Q080Ltet
return items; )z_5I (?&
} dFl8 'D
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publicvoid setItems(List items){ hDf!l$e.
this.items = items; 6QYHPz
} iBt<EM]U/
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publicint getPageSize(){ O>LqpZ
return pageSize; W,5_i7vr
} 0O!A8FA0
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publicvoid setPageSize(int pageSize){ 5D <
this.pageSize = pageSize; A
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} !DkIM}.
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publicint getTotalCount(){ `$Y%c1;
return totalCount; 2@Zw#2|]
} N5b^
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publicvoid setTotalCount(int totalCount){ =bOMtQ]
if(totalCount > 0){ 7?ILmYBw
this.totalCount = totalCount; ?P;=_~X
int count = totalCount / s[;1?+EI
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pageSize; |,T"_R_K
if(totalCount % pageSize > 0) .umN>/o[
count++; b( ~#CHg
indexes = newint[count]; #G\Ae:O
for(int i = 0; i < count; i++){ u`"Y!*[ -
indexes = pageSize * F8xu&Vk0:
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} "8
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}else{ I2gSgv%
this.totalCount = 0; n5Mhp:zc,
} qOAhBZ~
} nK`H;k
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publicint[] getIndexes(){ Mehp]5*
return indexes; M hjIE<OI=
} ab[V->>%
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publicvoid setIndexes(int[] indexes){ hyY^$p+
this.indexes = indexes; L+Gi
} ; hU9_e
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publicint getStartIndex(){ RN$q,f[#
return startIndex; Ch]q:o4
} ceLr;}?Ws
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publicvoid setStartIndex(int startIndex){ &zPM#Q
if(totalCount <= 0) \}Kad\)
this.startIndex = 0; +A%zFF3
elseif(startIndex >= totalCount) Xy9'JVV6
this.startIndex = indexes u@aM8Na
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[indexes.length - 1]; <#~n+,
elseif(startIndex < 0) \\/
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this.startIndex = 0; w_YY~Af
else{ `Mo%)I<`=
this.startIndex = indexes -./Y
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[startIndex / pageSize]; O>ZJOKe
} hG3RZN#ejq
} aX~'
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publicint getNextIndex(){ "H{#ib_c_
int nextIndex = getStartIndex() + ~5Rh7
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pageSize; *gI9CVfQl
if(nextIndex >= totalCount) &HJ~\6r\
return getStartIndex(); Kw>gg
else OmP(&t7
return nextIndex; bre6SP@
} [oH,FSuO!2
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publicint getPreviousIndex(){ .sUL5`
int previousIndex = getStartIndex() - F#{PJ#
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pageSize; D7$xY\0r
if(previousIndex < 0) zyI4E\
return0; 7M9s}b%?
else ::8E?c
return previousIndex; Fw;Y)y=O
} p|w;StLy
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} #/pZ#ny
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抽象业务类 9a_(_g>S
java代码: Va'K~$d_
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/** {EupB?
* Created on 2005-7-12 ]0:R^dHE
*/ LvS3c9|Aj
package com.javaeye.common.business; z'X_s.9F
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import java.io.Serializable; 9/|i.2&
import java.util.List; ByZ.!~
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import org.hibernate.Criteria; egi?Qg
import org.hibernate.HibernateException; o[ %Q&u
import org.hibernate.Session; ,K6]Q|U@r
import org.hibernate.criterion.DetachedCriteria; L7%'Y}1e.
import org.hibernate.criterion.Projections; Vt4}!b(O
import YKvFZH)
@kwD$%*0
org.springframework.orm.hibernate3.HibernateCallback; /ADxHw`k
import (^Do#3
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org.springframework.orm.hibernate3.support.HibernateDaoS pN]Hp"v
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upport; Azz]TO
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import com.javaeye.common.util.PaginationSupport; -{b1&
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public abstract class AbstractManager extends c[y=K)<Z
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HibernateDaoSupport { sqZHk+<%
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privateboolean cacheQueries = false; /?XfVhA:A
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privateString queryCacheRegion; b);}x1L.T
}lb.3fqiA
publicvoid setCacheQueries(boolean VYAe!{[
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cacheQueries){ xBG1up<z
this.cacheQueries = cacheQueries; +tN-X'u##
} (P>vI'
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publicvoid setQueryCacheRegion(String 5~"=Fm<uD
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queryCacheRegion){ %ej"ZeM
this.queryCacheRegion = }I`|*6Up
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queryCacheRegion; H= y-Y_R
} E0pQRGPA
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publicvoid save(finalObject entity){ QE}@|H9xs
getHibernateTemplate().save(entity); ?hu 9c
} HY:@=%R
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publicvoid persist(finalObject entity){ (~GFd7
getHibernateTemplate().save(entity); G9[-|[j^N
} R`&ioRWj
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publicvoid update(finalObject entity){ N9ufTlq
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getHibernateTemplate().update(entity); mC7Y *
} :jX~]1hpmA
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publicvoid delete(finalObject entity){ N
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getHibernateTemplate().delete(entity); %ze1ZWO{
} h,+=h;!
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publicObject load(finalClass entity, {\&"I|dpe
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finalSerializable id){ ka3Z5
return getHibernateTemplate().load ,f+5x]F?m
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(entity, id); \G@6jn1G(
} >i%w'uU
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publicObject get(finalClass entity, $rEd5W&d!
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finalSerializable id){ SEIu4
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return getHibernateTemplate().get n y)P
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(entity, id); |mmG
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} |q2lTbJ
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publicList findAll(finalClass entity){ ef;L|b%pp
return getHibernateTemplate().find("from Zbh]OCN
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" + entity.getName()); YXVJJd$U
} c$kb0VR
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publicList findByNamedQuery(finalString ^u!Tyb8Dk
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namedQuery){ M%s$F@
return getHibernateTemplate FraW6T}_
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().findByNamedQuery(namedQuery); s@LNQ|'kO
} -==qMrKP
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publicList findByNamedQuery(finalString query, >Ryss@o
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finalObject parameter){ ;sR6dT)
return getHibernateTemplate n
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().findByNamedQuery(query, parameter); .l=*R7~EU
} Au} ;z6k
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publicList findByNamedQuery(finalString query, +c8AbEewg
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finalObject[] parameters){ Z#6~N/b
return getHibernateTemplate Jrd4a~XP
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().findByNamedQuery(query, parameters); b]<HhU
} .k,Jt+
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publicList find(finalString query){ 04guud }
return getHibernateTemplate().find iSr`fQw#
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(query); A!W"*WT
} {jM<t
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publicList find(finalString query, finalObject noh|/sPMD
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parameter){ *$Lz2 ]
return getHibernateTemplate().find
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(query, parameter); WiNr866nB
} 5B>Q6
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public PaginationSupport findPageByCriteria S*CLt
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(final DetachedCriteria detachedCriteria){ w.D4dv_H
return findPageByCriteria P#[IUXtT
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); hg&w=l
} 2~M;L&9-
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public PaginationSupport findPageByCriteria *9dV/TT~f[
@TA8^ND
(final DetachedCriteria detachedCriteria, finalint XhE$&Ff
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startIndex){
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return findPageByCriteria /[Bl
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(detachedCriteria, PaginationSupport.PAGESIZE, Iys6R?~
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startIndex); H_?;h-Y]
} ;48P vw>g}
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public PaginationSupport findPageByCriteria G-\<5]k]
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(final DetachedCriteria detachedCriteria, finalint |?x^8e<*
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pageSize, Z!wD~C"D73
finalint startIndex){ e1%rVQ(v
return(PaginationSupport) Zk]k1]u*5
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getHibernateTemplate().execute(new HibernateCallback(){ hz<|W5
publicObject doInHibernate
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(Session session)throws HibernateException { OlEpid'Z
Criteria criteria = #"Fg%36Zd
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detachedCriteria.getExecutableCriteria(session); <^#P6
int totalCount = 4-y6MH
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((Integer) criteria.setProjection(Projections.rowCount gWFL
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()).uniqueResult()).intValue(); .r ~'(g{qt
criteria.setProjection U+4HG
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(null); M} O[`Fx{W
List items = jZrY=f
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criteria.setFirstResult(startIndex).setMaxResults 9n_ eCb)H
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(pageSize).list(); DXKyRkn6e
PaginationSupport ps = (F_w>w.h
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new PaginationSupport(items, totalCount, pageSize, - dl}_
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startIndex); GUKDhg,W
return ps; %njOX#.w
} GXO4x|08F
}, true); =h(7rU"Yz
} Q5g,7ac8L
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public List findAllByCriteria(final 6!Qknk$
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DetachedCriteria detachedCriteria){ L5/mO6;k
return(List) getHibernateTemplate 1c'79YU
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().execute(new HibernateCallback(){ Ga.0Io&}C
publicObject doInHibernate 9-b 8`|s
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(Session session)throws HibernateException { Eevw*;$x
Criteria criteria = 9MT3T?IS
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detachedCriteria.getExecutableCriteria(session); =m~ruZ/
return criteria.list(); ~,T+JX
} .`Sw,XL5
}, true); NK~PcdGl
} M</Wd{.g"
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public int getCountByCriteria(final C*a,<`
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DetachedCriteria detachedCriteria){ zLL)VFCJW
Integer count = (Integer) rfX=*mjt
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getHibernateTemplate().execute(new HibernateCallback(){ bGu([VB
publicObject doInHibernate kB
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(Session session)throws HibernateException { ?&6Q%IUW1
Criteria criteria = ^@K
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detachedCriteria.getExecutableCriteria(session); (V!0'9c
return FJ}gUs{m
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criteria.setProjection(Projections.rowCount pu#[pa
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()).uniqueResult(); a}dw9wU!:
} mVt3WZa
}, true); :WO{x g
return count.intValue(); j$mz3Yk
} "Vx6 #u@}
} Mb1wYh
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用户在web层构造查询条件detachedCriteria,和可选的 >MPa38
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Cx,-_
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PaginationSupport的实例ps。 {"t5\U6cKM
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ps.getItems()得到已分页好的结果集 '-.wFB;
ps.getIndexes()得到分页索引的数组 hX3@f;[B2
ps.getTotalCount()得到总结果数 gs>A=A(VYf
ps.getStartIndex()当前分页索引 tpZ->)1
ps.getNextIndex()下一页索引 C99&L3bz^(
ps.getPreviousIndex()上一页索引 .:N:p We
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7@3sUA_Go
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 "k, K ~@}
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一下代码重构了。 Yv=g^tw
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我把原本我的做法也提供出来供大家讨论吧: {=iyK/Uf
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首先,为了实现分页查询,我封装了一个Page类: ayeCi8
java代码: 37jQ'O
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/*Created on 2005-4-14*/ C=[Ae,
package org.flyware.util.page; U{HML|
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/** p&O8qAaO
* @author Joa ~j]dct7
* > Y]_K
*/ 3a^)u-9,x
publicclass Page { }<&d]N
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/** imply if the page has previous page */ 70=(.[^+
privateboolean hasPrePage; =]d^3bqN
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/** imply if the page has next page */ 'e85s%ru
privateboolean hasNextPage; BjvdnbJg
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/** the number of every page */ FR["e1<0
privateint everyPage; Vmtzig3w[
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/** the total page number */ J?,?fqb
privateint totalPage; ]LVnt-q
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/** the number of current page */ ]zcV]Qj$~
privateint currentPage; lz}llLb1
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/** the begin index of the records by the current zhjJ>d%w
PLdf_/]-
query */ >Zo-wYG
privateint beginIndex; m#;.yR
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/** The default constructor */ *0\k
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public Page(){ V(DjF=8
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} zu<>"5}]
@ct#s:t
/** construct the page by everyPage m|mG;8}pI
* @param everyPage O/$ v69:
* */ ?;fv!'?%
public Page(int everyPage){ QY=QQG
this.everyPage = everyPage; Yx!n*+ :J
} 'z~KTDX
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/** The whole constructor */ 9!cW
public Page(boolean hasPrePage, boolean hasNextPage, y/H8+0sEk
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int everyPage, int totalPage, sv@}x[L
int currentPage, int beginIndex){ ,rXW`7!2
this.hasPrePage = hasPrePage; $:P[v+Uy
this.hasNextPage = hasNextPage; (a,6a
this.everyPage = everyPage; (KZUvsS k
this.totalPage = totalPage; uQ-WTz|*
this.currentPage = currentPage; gl Li
this.beginIndex = beginIndex; 8XgVY9]Qm
} =g1 D;
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/** POkXd^pI
* @return WI%zr2T
* Returns the beginIndex. p<ry$=`
*/ @i;L Za
publicint getBeginIndex(){ YK7gd|LR]
return beginIndex; x>'?IJZ
} /]P%b K6B
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/** UqY J#&MqY
* @param beginIndex zR_9D}
* The beginIndex to set. ;H`=):U
*/ &0?DL
publicvoid setBeginIndex(int beginIndex){ l^)o'YS y
this.beginIndex = beginIndex; 3~#Z E;>#
} ~y( ,EO
@?(nwj~ s`
/** T
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* @return d91I
* Returns the currentPage. &:IfhS
*/ 9_I[o.q
publicint getCurrentPage(){ Mp}!+K
return currentPage; q_OY sg
} Djg1Qh
6yV5Yjs
/** $yP'k&b!
* @param currentPage 3uB=L7.
* The currentPage to set. Y0R\u\b
*/ Te{aB"B
publicvoid setCurrentPage(int currentPage){ TPV6$a <
this.currentPage = currentPage; p7?CeyZ-V
} `Pz!SJ|
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/** )eIz{Mdp=
* @return rF
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* Returns the everyPage. zM3H@;}m
*/ mH7CgI
publicint getEveryPage(){ j};pv 2
return everyPage; ?(|TP^
} M4L~bK
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/** @eAGN|C5
* @param everyPage !/=9VD{U!
* The everyPage to set. NoSqzJyh
*/ 8xeun~e"vS
publicvoid setEveryPage(int everyPage){ A1=$kzw{UH
this.everyPage = everyPage; VLwJ6?.f'
} \!' {-J
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/** { 8|Z}?I
* @return *n$m;yI
* Returns the hasNextPage. nFf\tf%8
*/ i &SBW0)
publicboolean getHasNextPage(){ 2=Vkjh-
return hasNextPage; 8m13M5r
} D;
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/** Nsy9
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* @param hasNextPage XQ4^:3Yc
* The hasNextPage to set. h>`'\qy
*/ j_YZ(: =
publicvoid setHasNextPage(boolean hasNextPage){ EcS-tE4%
this.hasNextPage = hasNextPage; MIMPJXT#.
} 1dgN10
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/** %]= 'Uv^x
* @return O<H@:W#k
* Returns the hasPrePage. XH Zu>[
*/ 1H2u,{O
publicboolean getHasPrePage(){ yrvSbqR
return hasPrePage; ju2X*
} y0mg}N1
/EAQ.vxI
/** kI1{>vYD
* @param hasPrePage x.4)p6
* The hasPrePage to set. (L6]uNOG
*/ f+W[]KK*PW
publicvoid setHasPrePage(boolean hasPrePage){ 7_d#XKz@
this.hasPrePage = hasPrePage; TYLl_nGr
} ]V]@Zna@g
NB6h/0*v
/** H f mMf^c
* @return Returns the totalPage. }JTgj
* 2W-NCE%K)T
*/ >A@D;vx
publicint getTotalPage(){ /
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return totalPage; -H]f@|AOw
} @IKe<{w
v}*u[GWl]
/** "l;8
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* @param totalPage W2LblZE!
* The totalPage to set. N %/DN
*/ ?kxWj(D
publicvoid setTotalPage(int totalPage){ .nY6[2am
this.totalPage = totalPage; BNm va
} G78j$
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} %IXW|mi
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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 =]mx"0i[
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个PageUtil,负责对Page对象进行构造: cTx/Y&\9
java代码: 3kQ8*S
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/*Created on 2005-4-14*/ _Vf|F
package org.flyware.util.page; xVX||rrh
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import org.apache.commons.logging.Log; O7*i;$!R
import org.apache.commons.logging.LogFactory; =0yJ2[R7Do
wz)9/bL
/** ho$%7mc
* @author Joa zFQkUgb
* _VJwC|
*/ 9yAu<a
publicclass PageUtil { 2,nCGSfc
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privatestaticfinal Log logger = LogFactory.getLog <&Xq`i/(
2/N*Uk 0
(PageUtil.class); z5'nS&x
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/** g$LwXfg
* Use the origin page to create a new page Y &+/[[
* @param page ,lM2BXz%
* @param totalRecords c)fp;^
* @return 6u;(R0n
*/ BQg]$Tr?
publicstatic Page createPage(Page page, int l);8y5
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totalRecords){ aC 0Jfo
return createPage(page.getEveryPage(), M3`A&*\;
Mp=+*I[
page.getCurrentPage(), totalRecords); /=} vPey
} Tyl"N{ _
!,"G/}'^;
/** XS/TYdXB8
* the basic page utils not including exception 4gENV{L
h_!"CF<n
handler e[!>ezaIY
* @param everyPage czRh.kz,
* @param currentPage h]P$L>
* @param totalRecords &N ;6G`3
* @return page |;yb *
*/ rd{(E
publicstatic Page createPage(int everyPage, int a-y5 \x
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currentPage, int totalRecords){ ;v\n[
everyPage = getEveryPage(everyPage); 1[]cMyV
currentPage = getCurrentPage(currentPage); V.1sZYA9
int beginIndex = getBeginIndex(everyPage, zPYa@0I
p.|;
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currentPage); r kl7p?
int totalPage = getTotalPage(everyPage, }Jfo(j
_I!&w!3oM
totalRecords); (6{
VMQ
boolean hasNextPage = hasNextPage(currentPage, i$bBN$<b<
9A!qg<
totalPage); H"l'E9k.&p
boolean hasPrePage = hasPrePage(currentPage); #v-!GK_<
ND>}t#^$
returnnew Page(hasPrePage, hasNextPage, 4KnDXQ%
everyPage, totalPage, Zpmy)W]1
currentPage, 8^lXM-G-
_?ZT[t<
beginIndex); Y<v55m-
} icmDPq
0"N %Vm
privatestaticint getEveryPage(int everyPage){ K~]jXo^M
return everyPage == 0 ? 10 : everyPage; Up&q#vqIj
} L/I-(08!Y:
rL=$WxdPU
privatestaticint getCurrentPage(int currentPage){ %}[??R0
return currentPage == 0 ? 1 : currentPage; *)<tyIHd
} OBZj-`fq J
jVz1`\Nje
privatestaticint getBeginIndex(int everyPage, int \<} nn?~n
UL/>t}AG
currentPage){ sq_:U_tJ
return(currentPage - 1) * everyPage; j4h 7q<
} |zMQe}R@%
ect?9S[!y
privatestaticint getTotalPage(int everyPage, int 7}Sw(g)o7
LjH];=R
totalRecords){ L*z;-,
int totalPage = 0; ($wYawz
/ @&Sqv4?
if(totalRecords % everyPage == 0) o;.-I[9h]
totalPage = totalRecords / everyPage; llzl-2`/
else Ut+m m\7
totalPage = totalRecords / everyPage + 1 ; D&shrKFx
&a`-NRU#
return totalPage;
v>XE]c_
} xn"g_2Hi
<da! #12L
privatestaticboolean hasPrePage(int currentPage){ bbJa,}R
return currentPage == 1 ? false : true; F!xK#~e
} S;])Nt'X'
i"'k|TGW^
privatestaticboolean hasNextPage(int currentPage, O v-I2
g_=Q=y@,
int totalPage){ ?]t8$^m,;
return currentPage == totalPage || totalPage == )d(cXN-T
P}5aN_v\
0 ? false : true; ;Gi w7a)
} gDsZbmR
#xc[)Y,W
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} AKpux,@xB
`#R$
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E8xXr>j>#
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。 mK4a5H
;cO0Y.V9l
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 8{ep`$(K@
' 9,}N:p
做法如下: 9xWrz;tzo
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 oqj3Q
1
,y0kzwPR1
的信息,和一个结果集List: OD i)#
java代码: ESs)|t h
/90@ 85%r
sLTf).xh
/*Created on 2005-6-13*/ b ,cvQD
package com.adt.bo; 4_mh
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import java.util.List; 8ZN J}
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import org.flyware.util.page.Page; :70oO}0m.
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/** #C+0m`
* @author Joa GL /\uq
*/ PY^Yx$t9
publicclass Result { @1>83-p"X
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private Page page; :g,r l\S7
=v_ju;C=
private List content; %|;^[^7+}t
_
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/** iw#luHcJ
* The default constructor hP7nt
*/ b*bR<|dT j
public Result(){ ^=t yf&"
super(); 1D*eu
} [iDa6mcth
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/** `xtN+y F
* The constructor using fields jReI+
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* LJBoS]~
* @param page N8KHNTb-M
* @param content ~[[a7$_4
*/ x$Lt?'
public Result(Page page, List content){ F~{4)`
this.page = page; t$}+oCnkv
this.content = content; ?56Zw"89
} UP,(zKTA
t rHj7Nw
/** HHX9QebiST
* @return Returns the content. 2bCa|HTv
*/ >8RIMW2
publicList getContent(){ js>6Du
return content; 'dx4L }d
} i4- >XvC
n%ld*EgY
/** BkIvoW_
* @return Returns the page. (V
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*/ !{SEm"J^
public Page getPage(){ _/KW5
return page; mhcJ0\@_
} /A_
IS `
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/** atPf527\`
* @param content <q_H 3|
* The content to set. -,Q<*)q{
*/ Ron^PvvY&
public void setContent(List content){ N'^ 0:zK:
this.content = content; 1Ce:<.99B
} c>]_,Br~
&*0!${B
/** ,PY<AI^59
* @param page hR. EZ|.
* The page to set. C@KYg/nYw
*/ S?D2`b
publicvoid setPage(Page page){ 0V1kZ.
this.page = page; v}iJ:'
} *aTM3k)Zs
} fF>H7
5Lue.U%a
Va9vDb6
#{N#yReh
dAga(<K
2. 编写业务逻辑接口,并实现它(UserManager, Q y15TJ
!vG._7lPp
UserManagerImpl) rPQ$e!m1Ee
java代码: \f._I+gJ
L !{^^7
o2%"Luf<
/*Created on 2005-7-15*/ N\H(AzMw
package com.adt.service; gzw[^d
F.AO
import net.sf.hibernate.HibernateException; {\ .2h
,kLeK{
import org.flyware.util.page.Page; _&yQW&vH#
GZO,]%z
import com.adt.bo.Result; QAX+oy
QI!:+8
/** p|W:;(
* @author Joa K)^.96{/@
*/ i3f/{D/
publicinterface UserManager { !M}&dW2
0k3^+#J
public Result listUser(Page page)throws KX*e2 /0
aIkxN&
HibernateException; .k[Ptx>
P^&+ehp
} *r(iegO$
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7MU
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;/ p)vR
java代码: ~lQ]PKJ"
mA{gj[@:x
|n]^gTJt
/*Created on 2005-7-15*/ 1q/z&@+B
package com.adt.service.impl; `SOaQ|H
[?;oiEe.|
import java.util.List; W6]iJ
r\L:JTZ$
import net.sf.hibernate.HibernateException; -7\RO%U
A7ck-9dT/L
import org.flyware.util.page.Page; g,x$z~zU{
import org.flyware.util.page.PageUtil; JB**z00;
WqwD"WX+w
import com.adt.bo.Result; R'&^)_
import com.adt.dao.UserDAO; Jb_/c``
import com.adt.exception.ObjectNotFoundException; a#KxjVM
import com.adt.service.UserManager; 9/^4W.
;Q-sie(#
/** o1YhYA
* @author Joa 69rVW~Z
*/ mnG\UK,k
publicclass UserManagerImpl implements UserManager { \b~zyt6-
w[loV
private UserDAO userDAO; ]}C#"Xt
|1rBK.8
/** 5tQffo8t
* @param userDAO The userDAO to set. >uxak2nM-
*/ G=\rlH]N
publicvoid setUserDAO(UserDAO userDAO){ Ho*S>Y
this.userDAO = userDAO; qCIZW
} SyTcp?H
sp'q=^t
/* (non-Javadoc) KvC:(Vqj
* @see com.adt.service.UserManager#listUser ]ujH7T
wG19NX(
(org.flyware.util.page.Page) jhK&Z7;
*/ *$uKg zv3
public Result listUser(Page page)throws )HR'FlxOd
F;`es%8
HibernateException, ObjectNotFoundException { ;Mw9}Reh@
int totalRecords = userDAO.getUserCount(); : 8(~{<R
if(totalRecords == 0) _d)w, ;m#
throw new ObjectNotFoundException aU 5t|S6
Mm|HA@W^
("userNotExist"); vy6NH5Q
page = PageUtil.createPage(page, totalRecords); '$l*FWOEal
List users = userDAO.getUserByPage(page); EGU?54
returnnew Result(page, users); S\GG(#b!
} TY~0UU$
A#LK2II^
}
9JP{F
Vs\)w>JF
r'w5i1C+
$;"@;Lj%,
kRZ(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 U#@:"v|
H~@aT7
询,接下来编写UserDAO的代码: u [fQvdl
3. UserDAO 和 UserDAOImpl: {I`B?6K5
java代码: X[grVe
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4hZ-^AL"(
/*Created on 2005-7-15*/ D)4p8-=t
package com.adt.dao; d<fS52~l
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import java.util.List; <N+l"Re#]
"yL&?B"9@
import org.flyware.util.page.Page; L.ndLd
oKzV!~{0M;
import net.sf.hibernate.HibernateException; |oPqX %?
t[)z/[m
/** Q]a5]:0
* @author Joa ]N2'L!4|;
*/ ||9f@9
publicinterface UserDAO extends BaseDAO { *E+)mB"~
p^\>{
publicList getUserByName(String name)throws [Z~>7ayF+)
R*VZ=i
HibernateException; >Py; 6K
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publicint getUserCount()throws HibernateException; 69O?sIk
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publicList getUserByPage(Page page)throws i|.!*/qF
1[u{3lQ
HibernateException; Scxf5x-
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} )u3<lpoTy
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lt5~rH2
tul5:}x3
java代码: Zff-Hl
&'T7 ~M:
pd>EUdbrp&
/*Created on 2005-7-15*/ }*IX34
package com.adt.dao.impl; /rKrnxw
>SSF:hI"J
import java.util.List; &..'7
NVJvCs)3f
import org.flyware.util.page.Page; |hOqz2|
AkT_ZU>
import net.sf.hibernate.HibernateException; 4Q_2GiF_
?
import net.sf.hibernate.Query; 9~Q.[ A
B7N?"'$i
import com.adt.dao.UserDAO; wjKW 3
r|?2 @VE
/** f0MHh5
* @author Joa <Pg.N
*/ ,B!u*
public class UserDAOImpl extends BaseDAOHibernateImpl aHwrFkn
^J@Y?CQl\
implements UserDAO { -L1{0{Z
?}B_'NZ%
/* (non-Javadoc) ]5uCs[
* @see com.adt.dao.UserDAO#getUserByName
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0Oe@0L%^3"
(java.lang.String) !oM1
*/ ]#+fQR$!
publicList getUserByName(String name)throws vF1]L]z:?
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HibernateException { l,,5OZw
String querySentence = "FROM user in class <7?MutHM-
9b()ck-\F#
com.adt.po.User WHERE user.name=:name"; d&.)Dw
Query query = getSession().createQuery 2l8jw:=H
#{i\t E
(querySentence); YadyRUE
query.setParameter("name", name); =;^2#UxXA&
return query.list(); >(~;V;
} }
Tp!Ub\Cc
8 :Z3Q
/* (non-Javadoc) MP0gLi
* @see com.adt.dao.UserDAO#getUserCount() 8Qek![3^
*/ 6W#M[0
publicint getUserCount()throws HibernateException { :);GeZ
int count = 0; ze!7qeW
String querySentence = "SELECT count(*) FROM o D:?fs]
dM#\h*:=
user in class com.adt.po.User"; ]?b#~
Query query = getSession().createQuery
Hco[p+
VT;$:>!+
(querySentence); b@z/6y!
count = ((Integer)query.iterate().next lN{-}f;TN
}3=]1jH6
()).intValue(); <_ddGg~
return count; mqw&SxU9
} l9#M`x9
|c dQJW
/* (non-Javadoc) trtI^^/%
* @see com.adt.dao.UserDAO#getUserByPage T+N%KRl
?IGT !'
(org.flyware.util.page.Page) 6'+3""\
*/ _z{:Q
publicList getUserByPage(Page page)throws |f?tyQ
N1+%[Uh9)
HibernateException { [bH6>{3u
String querySentence = "FROM user in class OAR#* ~q
()=
com.adt.po.User"; |*i0h`a
Query query = getSession().createQuery g}P.ksM
*|a_(bQ4@
(querySentence); Z&/bp 1
query.setFirstResult(page.getBeginIndex()) QV4{=1A
.setMaxResults(page.getEveryPage()); *:aJlvk
return query.list(); Ql3hq.E
} 7b \Hbg Z
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} rpQB#
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4{[Df$'e>
Jf YO|,
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至此,一个完整的分页程序完成。前台的只需要调用 7%V2
E[)`+:G]
userManager.listUser(page)即可得到一个Page对象和结果集对象 {ajaM'x
%q`_vtUT
的综合体,而传入的参数page对象则可以由前台传入,如果用 Ky|d RbK,
@K3<K(
webwork,甚至可以直接在配置文件中指定。 [wj&.I{^s
E#Smi507p
下面给出一个webwork调用示例: hwSn?bkw
java代码: sFT-aLpL@V
c7[|x%~
y.=ur,Nd
/*Created on 2005-6-17*/ &S>m+m'
package com.adt.action.user; F)z]QJOw
4ac2^`
import java.util.List; -WWa`,:
f-E]!\Pg
import org.apache.commons.logging.Log; #tRLvOR:
import org.apache.commons.logging.LogFactory; k id3@
import org.flyware.util.page.Page; 2,{m>fF
C{`+h163\
import com.adt.bo.Result; WV]Si2pOZ
import com.adt.service.UserService;
:,h47'0A
import com.opensymphony.xwork.Action; ps\A\aggML
7hlgm7^
/** {0 IEizQ|i
* @author Joa qL/4mM0
*/ C (L1
publicclass ListUser implementsAction{ K?+iu|$&
R4.$9_ui
privatestaticfinal Log logger = LogFactory.getLog _DnZ=&=MA
hX#y7m
(ListUser.class); sgW*0o
O8%+5l`T!
private UserService userService; "g;^R/sfq
JL5
)
private Page page; v9QR,b`n
4D=p#KZ
privateList users; vq-Tq>
kTZ`RW&0
/* P~HzNC
* (non-Javadoc) i0;
p?4`m
* :Q@=;P2
* @see com.opensymphony.xwork.Action#execute() t}n:!v"|+O
*/ a NhI<.v
publicString execute()throwsException{ *8{PoD
Result result = userService.listUser(page); Y3KKskhLx
page = result.getPage(); 1Tz5tU9kR
users = result.getContent(); sOQF_X(.x
return SUCCESS; s
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} v[~e=^IIsl
Jn!-Wa,
/** Sqw:U|h\FS
* @return Returns the page. 5$9g4
*/ TJjcX?:(
public Page getPage(){ ZZ|a`U
return page; \ t4:(Jp 3
} KKB&)R
b{q-o <