Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 wFL3&*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %S#WPD'Y
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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 ow.6!tl0=h
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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 onl>54M^
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分页支持类: 9;KJr[FQV
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java代码: &U&%ka<*
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package com.javaeye.common.util; ]}2Ztr)zZ
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import java.util.List; d
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publicclass PaginationSupport { ~FUa:KYD
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publicfinalstaticint PAGESIZE = 30; mU G
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privateint pageSize = PAGESIZE; aqr!oxn?t
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privateList items; (wA?;]q(
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privateint totalCount; }*kJ-q&0
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privateint[] indexes = newint[0]; .ECHx Dp
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privateint startIndex = 0; cZQu *K^j
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public PaginationSupport(List items, int m0( E kK
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totalCount){ i'tp1CI
setPageSize(PAGESIZE); SRz&Nb
setTotalCount(totalCount); TzM=LvA
setItems(items); 2QayM?k8
setStartIndex(0); e.;M.8N#SQ
} )U(u>SV(\
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public PaginationSupport(List items, int (5`T+pAsV
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totalCount, int startIndex){ AcC8)xRpk4
setPageSize(PAGESIZE); O&$0&dhc
setTotalCount(totalCount); Iql5T#K+
setItems(items); 0kLEBoOh
setStartIndex(startIndex); vA-PR&
} SS8ocGX
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public PaginationSupport(List items, int Lk.h.ST
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totalCount, int pageSize, int startIndex){ agsISu(
setPageSize(pageSize); cZ<
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setTotalCount(totalCount); B\_[R'Pf&
setItems(items); FH\CK
setStartIndex(startIndex); cY{Nos
} DO^y;y>
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publicList getItems(){ NWKi
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return items; m m, lhIh
} Hj~O49%j&
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publicvoid setItems(List items){ jXR16|
this.items = items; 5(J^N
} o'Y#H
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publicint getPageSize(){ PqEAqP
return pageSize; 'ZnIRE,N
} -:]@HD :
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publicvoid setPageSize(int pageSize){ #IX&9 aFB}
this.pageSize = pageSize; MUcNC\`z
} 7rIlTrG
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publicint getTotalCount(){ ]Oso#GYD
return totalCount; >saI+u'o
} GS%b=kc
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publicvoid setTotalCount(int totalCount){ #nEL~&
if(totalCount > 0){ \A(5;ZnuD
this.totalCount = totalCount; 3k{ @.V?]
int count = totalCount / .#!mDlY;
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pageSize; (I=6Nnt'
if(totalCount % pageSize > 0) RvW.@#EH0
count++; aZgNPw
indexes = newint[count]; )w"0w(
for(int i = 0; i < count; i++){ y Nva1I
indexes = pageSize * 4<}A]BQVkJ
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} J
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}else{ p\S8oHWe
this.totalCount = 0; `C'}e
} afm_ Rrg[
} 'h}7YP, w
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publicint[] getIndexes(){ kZ[mM'u#
return indexes; ]^@0+!
} e@j8T
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publicvoid setIndexes(int[] indexes){ @ER1zKK?
this.indexes = indexes; x/ I;nMY
} 0<&M?^
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publicint getStartIndex(){ u^=@DO'
return startIndex; jG8;]XP
} !6E:5=L^
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publicvoid setStartIndex(int startIndex){ lzfDH=&
if(totalCount <= 0) ORH93`
this.startIndex = 0; E@pFTvo
elseif(startIndex >= totalCount) F=i!d,S
this.startIndex = indexes NI\H
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[indexes.length - 1]; /=ylQn3
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elseif(startIndex < 0) 7;xKy'B\
this.startIndex = 0; q\H7&w
else{ 1+^n!$
this.startIndex = indexes $L&BT 0
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[startIndex / pageSize]; %6 ]\^
} 4oJ$dN
} +/q0Y`v
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publicint getNextIndex(){ J3&Sj{ o
int nextIndex = getStartIndex() + .)`-Hkxa
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pageSize; *?N<S$m
if(nextIndex >= totalCount) <E}N=J'uJ
return getStartIndex(); }+DDJ6Jzs
else C1 {ZW~"YI
return nextIndex; xid:" y=_&
} T} 8CfG_j
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publicint getPreviousIndex(){ o)!m$Q~v
int previousIndex = getStartIndex() - owMmCR
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pageSize;
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if(previousIndex < 0) wlVvxX3%
return0; s3< F
else .. UoyBV
return previousIndex; <[9?Rj@
} (nz}J)T&
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} ~B]jV$=
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抽象业务类 fq(5Lfe}
java代码: d h?dO`
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/** kaO{#i2-
* Created on 2005-7-12 yoW>
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*/ jGiw96,Y
package com.javaeye.common.business; 4:`[q E3
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import java.io.Serializable; 2Oi' E
import java.util.List; Y^3)!>
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import org.hibernate.Criteria; _H2tZ%RM
import org.hibernate.HibernateException; >Bx8IO1_\d
import org.hibernate.Session; 5Hy3\_ +
import org.hibernate.criterion.DetachedCriteria; >[P%Ty);
import org.hibernate.criterion.Projections; >{F!ntEj
import os_WYQ4>j
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org.springframework.orm.hibernate3.HibernateCallback; O+vcs4
import OQc{
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org.springframework.orm.hibernate3.support.HibernateDaoS N(BiOLZL6
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upport; x~Cz?ljbn
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import com.javaeye.common.util.PaginationSupport; 3W'FcE)|E
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public abstract class AbstractManager extends 4Pf+]R
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HibernateDaoSupport { ZM
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privateboolean cacheQueries = false; jYk5~<\k
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privateString queryCacheRegion; Z>h{`
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publicvoid setCacheQueries(boolean QE*%HR'
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cacheQueries){ x97H(*
this.cacheQueries = cacheQueries; wo]ks}9
} oX*b<d{\N
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publicvoid setQueryCacheRegion(String _G[6+g5|
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queryCacheRegion){ r},lu=em
this.queryCacheRegion = !"%S#nrL$
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queryCacheRegion; UeNF^6sWu0
} F;W'
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publicvoid save(finalObject entity){ :fW.-^"VP
getHibernateTemplate().save(entity); My],6va^
} EO"6Dq(
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publicvoid persist(finalObject entity){ kAt
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getHibernateTemplate().save(entity); GqMB^Ad
} L^x5&CCwk
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publicvoid update(finalObject entity){ |
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getHibernateTemplate().update(entity); L,
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} S<9gyW
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publicvoid delete(finalObject entity){ $i -zMa
getHibernateTemplate().delete(entity); EFD?di)s
} _}^u-fJ/~
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publicObject load(finalClass entity, &rcdr+'
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finalSerializable id){ 2=O))^8
return getHibernateTemplate().load +dJ&tuL:S
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(entity, id); <ipWMZae0F
} q6Rw4
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publicObject get(finalClass entity, \D ^7Z97
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finalSerializable id){ N|o>%)R
return getHibernateTemplate().get ;)P5#S!n-
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(entity, id); JC/d:.
} !L/tLHk+
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publicList findAll(finalClass entity){ N?zV*ngBS
return getHibernateTemplate().find("from yj'Cy8
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" + entity.getName()); lqauk)(A0
} 8'n#O>V@
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publicList findByNamedQuery(finalString ss*5.(y
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namedQuery){ _E&U?>g+
return getHibernateTemplate X&/(x
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().findByNamedQuery(namedQuery); #U:0/4P(
} b13nE.
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publicList findByNamedQuery(finalString query, G$|G w
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finalObject parameter){ oH=4m~'V
return getHibernateTemplate $@68=
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().findByNamedQuery(query, parameter); }tu4z+T2
} t Z+0}d
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publicList findByNamedQuery(finalString query, + 2OZJVJ
{({
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finalObject[] parameters){ =1eV
return getHibernateTemplate G}Gb|sD
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}!Xf&c{7{
().findByNamedQuery(query, parameters); DhHtz.6
} N-Qu/,~+
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publicList find(finalString query){ GsI[N%
return getHibernateTemplate().find LMt0'Ml9
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(query); ykJ+%gla
} zI(xSX@
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publicList find(finalString query, finalObject Rz)v-Yu
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parameter){ x-tm[x@;o
return getHibernateTemplate().find u6]gQP">I
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(query, parameter); PE^eP}O1
} 9+W!k^VWq
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public PaginationSupport findPageByCriteria X #&(~1O
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(final DetachedCriteria detachedCriteria){ >xklt"*U,
return findPageByCriteria suzFcLxo
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); bN]\K/
} O}e|P~W
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public PaginationSupport findPageByCriteria @T9m}+fR
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(final DetachedCriteria detachedCriteria, finalint &~z+ R="=
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startIndex){ 2*N&q|ED
return findPageByCriteria <WO&$&
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(detachedCriteria, PaginationSupport.PAGESIZE, D1oaG0
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startIndex); F">Nrj-bs
} 0~Um^q*'3
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public PaginationSupport findPageByCriteria 5w]DncdQ~
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(final DetachedCriteria detachedCriteria, finalint L[`R8n1C
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pageSize, K-N]h
finalint startIndex){ vx({N?
return(PaginationSupport) d4b 9rtM
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getHibernateTemplate().execute(new HibernateCallback(){ 8XLxT(YFIs
publicObject doInHibernate Y:DNu9
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(Session session)throws HibernateException { ORUWslMt
Criteria criteria = F<6KaZ|
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detachedCriteria.getExecutableCriteria(session); |Ba4 G`
int totalCount = 3?a0
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((Integer) criteria.setProjection(Projections.rowCount Oex{:dO "F
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()).uniqueResult()).intValue(); eD>-`'7<
criteria.setProjection } S'I
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(null); 6n2Vx1b
List items = _C7abw-
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criteria.setFirstResult(startIndex).setMaxResults (OM?aW
.6lY*LI
(pageSize).list(); }CB=c]p
PaginationSupport ps = MAm1w'ol"
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new PaginationSupport(items, totalCount, pageSize, C:|q'"F
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startIndex); z&>9
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return ps; B:R7[G;1
} _ Yb
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}, true); \'\N"g`Fr
} sR7{ i
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public List findAllByCriteria(final w>H%[\Qs
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DetachedCriteria detachedCriteria){ ;o~+2Fir
return(List) getHibernateTemplate ae9k[=-
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().execute(new HibernateCallback(){ @p9e:[
publicObject doInHibernate +X2 i/}
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(Session session)throws HibernateException { /xX,
Criteria criteria = i_oro"%yL
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detachedCriteria.getExecutableCriteria(session); mh!N^[=n
return criteria.list(); W TXD4}
} ZNL;8sI?>
}, true); *@$($<pY&
} #z-iL!?
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public int getCountByCriteria(final ]yj4~_&O
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DetachedCriteria detachedCriteria){ ne!j%9Ar
Integer count = (Integer) 7gZVg@
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getHibernateTemplate().execute(new HibernateCallback(){ Skr\a\
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publicObject doInHibernate 0`g}(}'L
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(Session session)throws HibernateException { b]tA2~e
Criteria criteria = n]6}yJJo
@4 Os?_gJ\
detachedCriteria.getExecutableCriteria(session); -N-4l
return %>I?'y^
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criteria.setProjection(Projections.rowCount Y*5@|Q
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()).uniqueResult(); _!$Up
} Z;"4$@|qE
}, true); ^w&5@3d
return count.intValue(); O3<Y _I^
} eaYkYuS/
} ^J#*n;OQ3A
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用户在web层构造查询条件detachedCriteria,和可选的 +,{Wcb
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Z+`{JE#
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PaginationSupport的实例ps。 >2/wzsW
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ps.getItems()得到已分页好的结果集 ^ T:qT*v
ps.getIndexes()得到分页索引的数组 5u
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ps.getTotalCount()得到总结果数 3wa<,^kqy
ps.getStartIndex()当前分页索引 r:8]\RU
ps.getNextIndex()下一页索引 ]\os`At
ps.getPreviousIndex()上一页索引 :>er^\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @6i8RmOu}
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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 iuU3*yyn
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一下代码重构了。 xJF6l!`
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我把原本我的做法也提供出来供大家讨论吧: wTMHoU*>
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首先,为了实现分页查询,我封装了一个Page类:
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java代码: H>X>5_{}
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/*Created on 2005-4-14*/ utm+\/
package org.flyware.util.page; J:mu%N`
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/** 2
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* @author Joa ,T21z}r
* !ovZ>,1
*/ cJ(zidf_$
publicclass Page { 1R+ )T'in
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/** imply if the page has previous page */ .5[LQR
privateboolean hasPrePage; ! MF"e|W
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/** imply if the page has next page */ yY@s(:
privateboolean hasNextPage; ,0<F3h
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/** the number of every page */ g%q?2Nv
privateint everyPage; B,m$ur#$
}2!5#/^~
/** the total page number */ 3EW f|6RI
privateint totalPage; UN
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a
/** the number of current page */ d`],l\oC
privateint currentPage; {+UNjKQC
v YmtpKNj%
/** the begin index of the records by the current aa YQ<
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query */ +q_lYGTiO
privateint beginIndex; A@
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/** The default constructor */ lTOM/^L
public Page(){ 4-nr_
WCm4
%_@5_S
} DneSzqO"o
bmq XP
/** construct the page by everyPage 5t5S{aCDr
* @param everyPage v`ZusHJ1d
* */ uI-76
public Page(int everyPage){ s3E~X
this.everyPage = everyPage; m)]fJ_
} Mb2 L32
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/** The whole constructor */ <QoE_z`76
public Page(boolean hasPrePage, boolean hasNextPage, 7%"\DLA
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int everyPage, int totalPage, t>h
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int currentPage, int beginIndex){ y[5P<:&s
this.hasPrePage = hasPrePage; ]{6yS9_tuI
this.hasNextPage = hasNextPage; Q}f}Jf3P
this.everyPage = everyPage; Lv5
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this.totalPage = totalPage; ESf7b `tS
this.currentPage = currentPage; 'hi\98y
this.beginIndex = beginIndex; :iNAXy
} 5iI3u 7Mn1
$}nUK~$GSv
/** =5=Vm[
* @return 6 r-n6#=
* Returns the beginIndex. e%v4,8
*/ UV8r&O
publicint getBeginIndex(){ 8W<)c
return beginIndex; &'ETx"
} eP)YJe 3
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/** \/4%[Q2QDm
* @param beginIndex S{)n0/_
* The beginIndex to set. >]Yha}6h
*/ ZO0]+Ko
publicvoid setBeginIndex(int beginIndex){ tfKeo|DM"
this.beginIndex = beginIndex; a*8.^SdzR
} ;@Hi*d[
e%c5OZ3~
/** K#sb"x`
* @return i7FR78^
* Returns the currentPage. ?N?pe}
*/ pr,1Wp0l
publicint getCurrentPage(){ KJJb^6P48W
return currentPage; `rdfROKv
} WAmoKZw2
R6$F<;nw
/** GV@E<dg$R
* @param currentPage <^'+]?
* The currentPage to set. 4Hpu EV8Q
*/ utl=O
publicvoid setCurrentPage(int currentPage){ GGL4<P7
this.currentPage = currentPage; wfTv<WG,.E
} ?uX6X'-
#!&R7/
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/** )"Br,uIv:/
* @return jv=f@:[`I
* Returns the everyPage. c@#zjJhW]
*/ sCCr%r]zL
publicint getEveryPage(){ vrnj}f[h
return everyPage; 7>@/*S{X
} N3c)ce7[
}=m?gF%3
/** jMWwu+w
* @param everyPage +U)|&1oa
* The everyPage to set. bnY8.Lpf|
*/ cB F%])!
publicvoid setEveryPage(int everyPage){ @#Uiy5N
this.everyPage = everyPage; I_I;.Ik
} WCl;#=
'*;eFnmvs:
/** |{IU<o
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* @return u2O^3rG-
* Returns the hasNextPage. `b`52b\6S
*/ -&D6w9w
publicboolean getHasNextPage(){ ,zw=&)W1
return hasNextPage; _v=WjN
} |b~g^4
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/** dB/I2uGl>
* @param hasNextPage !3Z|!JY
* The hasNextPage to set. L\b_,'I
*/ A'-YwbY
publicvoid setHasNextPage(boolean hasNextPage){ C{,] 1X6g
this.hasNextPage = hasNextPage; zYF&Dv/u/
} )0d".Q|v4
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/** IeI%X\G
* @return NWwtq&pz2
* Returns the hasPrePage. UMW^0>Z!v
*/ $hp?5KM
publicboolean getHasPrePage(){ (IHBib "
return hasPrePage; il%tu<E#J~
} !;C(pnE
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/** H08YMP>dc
* @param hasPrePage iSLf:
* The hasPrePage to set. +9rbQ?'
*/ 6U9Fa=%>}
publicvoid setHasPrePage(boolean hasPrePage){ ayz1i:Q|
this.hasPrePage = hasPrePage; |/\1nWD
} $v@$oPmMj
=V]i?31[
/** Q09~vFBg
* @return Returns the totalPage. 58'y~Ou
* H>X1(sh#}
*/ cD@lorj
publicint getTotalPage(){ n(Op<
return totalPage; )^#Zg8L
} G6mM6(Sr
2MzFSmhc"
/** PH!B /D5G
* @param totalPage G/44gKl
* The totalPage to set. ^l9
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*/ jV&W[xKa
publicvoid setTotalPage(int totalPage){ E?D{/k,zZ
this.totalPage = totalPage; FGhrf
} 0M2+?aKif
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} .T wF]v
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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 pFRnPOv
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个PageUtil,负责对Page对象进行构造: '6J$X-
java代码: Eakjsk
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/*Created on 2005-4-14*/ HcS^3^Y
package org.flyware.util.page; F4(U~n<
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import org.apache.commons.logging.Log; 8>;o MM
import org.apache.commons.logging.LogFactory; Yx c >+mx
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/** irj}:f;!eF
* @author Joa |ema-pRC
* ,
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*/ 2dW-WHaM
publicclass PageUtil { g c=|<(
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privatestaticfinal Log logger = LogFactory.getLog 7B"aFnK;[J
)W JI=jl
(PageUtil.class); ^qr[?ky]&
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/** "z4E|s
* Use the origin page to create a new page yE{UV>ry
* @param page 4zbV' ]
* @param totalRecords io_64K+K
* @return b?L43t ,
*/ 9 NSYrIQ"
publicstatic Page createPage(Page page, int >m{-&1Tx
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totalRecords){ R$`T"C"
return createPage(page.getEveryPage(), o%Q2.
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page.getCurrentPage(), totalRecords); o7B+f
} OZ9j3Q;a$
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/** 0k]N%!U
* the basic page utils not including exception sRI8znus
:b)@h|4
handler T,@7giQg@
* @param everyPage 0_izTke
* @param currentPage y%Ah"UY
* @param totalRecords aKcV39brr
* @return page dU n#'<g5
*/ ( h,F{7
publicstatic Page createPage(int everyPage, int @},k\Is
L6qA=b~iz
currentPage, int totalRecords){ "+Rm4_
everyPage = getEveryPage(everyPage); 9j9?;3;
currentPage = getCurrentPage(currentPage); C,.{y`s'
int beginIndex = getBeginIndex(everyPage, oD`BX
Yy 1Pipv
currentPage); ||NCVGJG
int totalPage = getTotalPage(everyPage, ^T>.04";x
?id^v 7d
totalRecords); ]TN}`]
boolean hasNextPage = hasNextPage(currentPage, Q&{5.}L
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totalPage); cn{l
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boolean hasPrePage = hasPrePage(currentPage); Gl9 a5b
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returnnew Page(hasPrePage, hasNextPage, .<hv&t
everyPage, totalPage, l>q.BG
currentPage, UQr+\ u
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beginIndex); 6h8NrjX
} AlV2tffY^
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privatestaticint getEveryPage(int everyPage){ _~"3
LB
return everyPage == 0 ? 10 : everyPage; ?Kf@/jv
} aS2
Y6
#y%Ao\~kG
privatestaticint getCurrentPage(int currentPage){ $R4\jIewV
return currentPage == 0 ? 1 : currentPage; ,pepr9Yd
} 4f5$^uN$qA
ttrp|(
privatestaticint getBeginIndex(int everyPage, int hG)lVo!L4j
4 -W?u51"
currentPage){ h~t]WN
return(currentPage - 1) * everyPage; B[h9epU]K
} E>v~B;@
E"!*ASN
privatestaticint getTotalPage(int everyPage, int beoMLHp
so?1lG
totalRecords){ }o.ZCACYg
int totalPage = 0; c:5BQr
'
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if(totalRecords % everyPage == 0) ZO^+KE"
totalPage = totalRecords / everyPage; )vzT\dQ|
else @"0qS:s]X
totalPage = totalRecords / everyPage + 1 ; aleIy}"
2{\Y<%.
return totalPage; CJ b~~
} cj)~7 WF
^&%?Q_]
privatestaticboolean hasPrePage(int currentPage){ iV=#'yY
return currentPage == 1 ? false : true; L3\{{QOA
} n\4+xZr
f5v|}gMAX
privatestaticboolean hasNextPage(int currentPage, *']RYu?X
@ck2j3J/
int totalPage){ 6dp~19T^
return currentPage == totalPage || totalPage == j!/(9*\
'M{_S
0 ? false : true; wVTo7o%U
} va.wdk g
),eiJblH
$?YkgK
} ;.Y`T/eWS
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h2]Od(^[
ub%q<sE*
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 n:+MNr
'7^_$M3$\
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 :|g{gi
a@./e @p
做法如下: F=H=[pSe
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 '*:YC
.O(UK4Mb
的信息,和一个结果集List: <LE>WfmC
java代码: =9M-N?cV
*V/SI E*8
^B/{
/*Created on 2005-6-13*/ rRW&29A
package com.adt.bo; &wfM:a/c
|V&k1{V
import java.util.List; 2#^[`sFPO
P\R3/g
import org.flyware.util.page.Page; tg:x}n
V/Tp&+Z.c
/** d?>sy\{2
* @author Joa 4 ET
P
*/ =Ev } v
publicclass Result { q b'ka+X
aSj$62G"
private Page page; xab[
$f%_ 4 =
private List content; wJ}8y4O!N
@S}'_g
/** S=Zjdbd
* The default constructor O_033&
*/ V2*b f`/V
public Result(){ bm^ou#]|
super(); C>H UG
} >9DgsA`'
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/** 1g@kHq
* The constructor using fields lUrchLoDt
* rRMC<.=
* @param page vDemY"wz
* @param content [|3
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*/ v1:5r
public Result(Page page, List content){ I;7VX5X
this.page = page; h*Ej}_
this.content = content; SWu=n1J.?H
}
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/** zr,jaR;
* @return Returns the content. X*b0q J
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*/ L6FUC6x"
publicList getContent(){ r8qee$^M
return content; 607#d):Y
} hZy"@y3Yq
l4; LV7Ji
/** %n(
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* @return Returns the page. jE{z4en
*/ q>Y_I<;'g
public Page getPage(){ nQ mkDPjU
return page; *I~F7Z]|
} e='3gzz
a*=e 3nS
/** :ZUy(8%Wl
* @param content /];F4AO5
* The content to set. )2a!EEHz
*/ 7BC9cS(0w9
public void setContent(List content){ i"-j:b:c<
this.content = content; h"[
][
}
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YpiSH(70`
/** pDu~84!])
* @param page /HLQ
* The page to set. 7|2:;5:U
*/ ]xuq2MU,l
publicvoid setPage(Page page){ @sVBG']p
this.page = page; 1$c*/Tc:E
} 4X^0:.bT&
} wc;5tb#
L-fAT'!'
ohwQ%NDl
w ^r*qi"
W?.Y%wc0
2. 编写业务逻辑接口,并实现它(UserManager, }JI5,d
LnBkd:>}
UserManagerImpl) 4kx#=MLt
java代码: 1j}o.0\
<Wl!
Qog'
k(s3~S2h
/*Created on 2005-7-15*/ xa K:@/
package com.adt.service; sR5dC_
/6>2,S8Ar
import net.sf.hibernate.HibernateException; 2-8<uU y
#ujcT%1G
import org.flyware.util.page.Page; R(csJ4F
B-o"Y'iXs
import com.adt.bo.Result; b+{,c@1rd
;]p#PNQ0
/** ^E5Xpza
* @author Joa k%hif8y
*/ /H\ZCIu/7
publicinterface UserManager { o'W &gkb9
@#sQ7eMoy
public Result listUser(Page page)throws keX0br7u_
~,ac{%8x
HibernateException; %e3lb<sv6
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} D|OX]3~
Uq"RyvkpP
B
[03,zVf
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w^dB1Y7c(W
java代码: x*(pr5k
z]tvy).
K2NnA
/*Created on 2005-7-15*/ IUwY/R9Q
package com.adt.service.impl; lO<Ujb#"R
D`Fl*Wc4H
import java.util.List; u U\UULH0
Q5baY\"9^
import net.sf.hibernate.HibernateException; pS51fF9
tk ~7>S
import org.flyware.util.page.Page;
ZQ@^(64
import org.flyware.util.page.PageUtil; TMGZHOAt
Dj?95Z,r
import com.adt.bo.Result; 16xM?P
import com.adt.dao.UserDAO; ?eeE [F
import com.adt.exception.ObjectNotFoundException; Pf]L`haGN
import com.adt.service.UserManager; 6=FF*"-6E
aY6]NpT
/** V[CS{Hy'
* @author Joa he
9qWL&^G
*/ k4eV*e8
publicclass UserManagerImpl implements UserManager { Z#d_<e?
W)o-aX!P
private UserDAO userDAO; OfIml.
%$S.4#G2
/** i |cSO2O+
* @param userDAO The userDAO to set. XYf;72*
*/ ?f:FmgQk
publicvoid setUserDAO(UserDAO userDAO){ tXwnK[~x
this.userDAO = userDAO; Gu9Ap<>!
} ZCV&v47\p_
"c=\?
/* (non-Javadoc) !i0:1{.
* @see com.adt.service.UserManager#listUser g5_]^[upw
I9TOBn|6
(org.flyware.util.page.Page) `2 Z
*/ Q_]O[Kx
public Result listUser(Page page)throws vA"yy"B+ V
dfO84Z}
5
HibernateException, ObjectNotFoundException { iw<+rh*C
int totalRecords = userDAO.getUserCount(); J$@3,=L6V
if(totalRecords == 0) -&%#R_RV
throw new ObjectNotFoundException {'EQ%H$q
A03,X;S+
("userNotExist"); n`;=^^ B
page = PageUtil.createPage(page, totalRecords); "m(HQ5e)*
List users = userDAO.getUserByPage(page); =[3I#s?V
returnnew Result(page, users); Lw1~$rZg
} Tj@s \@hv
B!yAam#^
} NkA|T1w7
n*hHqZl
?tg(X[h{S
7l%O:M(\
(?;Fnq
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 `+{|k)2B
u0Irf"Ab
询,接下来编写UserDAO的代码: tBp dKJn##
3. UserDAO 和 UserDAOImpl: d%\en&:la
java代码: d 6j'[
(khjP,
m<hR
Lo
/*Created on 2005-7-15*/ /a(xUm @.
package com.adt.dao; /5EM;Mx
Z[[@O
import java.util.List; >ouHR*
7P|GKN~
import org.flyware.util.page.Page; zHeqV
Z<;am
import net.sf.hibernate.HibernateException; _/ ]4:("
4F^(3RKZ|
/** P]bI".A8
* @author Joa pk:YjJs
*/ xOp8[6Ga'
publicinterface UserDAO extends BaseDAO { rs`H':a/
q!t_qX7u
publicList getUserByName(String name)throws XSkx<"U*
t9;yyZh
HibernateException; Yx>=(B
7`thM/fN
publicint getUserCount()throws HibernateException; c>,|[zP{
BRhAL1
publicList getUserByPage(Page page)throws $i7iv
gk1I1)p
HibernateException; DfXXN
Rbm"Qz
} [yJcM
[p\
049E#[<Q"
\,+act"v
Dh*Uv,
C{H:-"\J9
java代码: ^/h,C^/;
8F9sKRq|rO
c!d>6:\
/*Created on 2005-7-15*/ }YfM<
package com.adt.dao.impl; TGl It<&
rd vq(\A
import java.util.List; lb{<}1YR0o
M[g9D
import org.flyware.util.page.Page; cNZuwS~,
}uz*6Z(S
import net.sf.hibernate.HibernateException; 0R z'#O32V
import net.sf.hibernate.Query; /r^J8B*
A(S =
import com.adt.dao.UserDAO; 7Y"CeU-S
dj3}Tjt
/** _3i.o$GO
* @author Joa xlg 6cO
*/ eZ'J,;
public class UserDAOImpl extends BaseDAOHibernateImpl NifzZEX
]>M{Qn*
implements UserDAO { tsaf|xe
5ztHar~f
/* (non-Javadoc) 'Y Bz?l9
* @see com.adt.dao.UserDAO#getUserByName |gxT-ZM
T:p,!?kc7
(java.lang.String) .KSPr
*/ z%Pbs[*C
publicList getUserByName(String name)throws kmXpj3
EZlcpCS
HibernateException { 3GqvL_
String querySentence = "FROM user in class U
bUl]
?BtWM4Id8
com.adt.po.User WHERE user.name=:name"; ?=}~]A5N
Query query = getSession().createQuery ]A+q:kP
f?}~$agc
(querySentence); ,<!_MNw[
query.setParameter("name", name); ^vw? 4O
return query.list(); V4@HIM
} wH&[Tg
,Wtod|vx\U
/* (non-Javadoc) n%yMf!M
.:
* @see com.adt.dao.UserDAO#getUserCount() |E/U(VS3l~
*/ <!g q9
publicint getUserCount()throws HibernateException { WP{!|d&
int count = 0; Xk8+
String querySentence = "SELECT count(*) FROM _?$P?
Q}.zE+
user in class com.adt.po.User"; f4eLnY
Query query = getSession().createQuery gBBS}HF
DlIy'@ .
(querySentence); Z:7X=t=
count = ((Integer)query.iterate().next YaI8hj@}
Ry2rQM`
()).intValue(); #!!Ea'3Iq
return count; jLRUWg
} WtlPgT;wE
;[9WB<t
/* (non-Javadoc) l8rBp87Q
* @see com.adt.dao.UserDAO#getUserByPage 'Pyeb`AXE9
X-[_g!pV
(org.flyware.util.page.Page) U,q
]
*/ "9mJ$us
publicList getUserByPage(Page page)throws gwHNz5 a*V
TNs;#Q
HibernateException { }$E cNm$%
String querySentence = "FROM user in class vd+yU9
$#E?`At{I
com.adt.po.User"; CDOqdBQ
Query query = getSession().createQuery N4y$$.uv2
M8j%bmd(,
(querySentence); `uK_}Vy_
query.setFirstResult(page.getBeginIndex()) X$z@ *3=
.setMaxResults(page.getEveryPage()); Byq4PX%B
return query.list(); Pt<lHfd
} 5R6@A?vr
ETQ.A< v
} H3<
`
DY]\@<ez
Gc6`]7 s
Id-?her>B
V0y Q
至此,一个完整的分页程序完成。前台的只需要调用 t<'-?B2g
^@V$'Bk
userManager.listUser(page)即可得到一个Page对象和结果集对象 &d/v/Y
_h;#\ )%~
的综合体,而传入的参数page对象则可以由前台传入,如果用 jn[%@zD }
:$eg{IXC"
webwork,甚至可以直接在配置文件中指定。 haj\Dm
G+Vlaa/7
下面给出一个webwork调用示例: O%:EPdoU
java代码: j(JUOief
D4jf%7X!Lu
.CXe*Vbd
/*Created on 2005-6-17*/ 0>PO4WFVJ
package com.adt.action.user; &Z
Ja}5k!r
?Uz7($}
import java.util.List; F^Q[P4>m\
\VJ7ahg[\
import org.apache.commons.logging.Log; f?xc-lX5R
import org.apache.commons.logging.LogFactory; 9AJMm1_
import org.flyware.util.page.Page; 49Sq)jd<
_ElA\L4g%
import com.adt.bo.Result; mG;Gt=4
import com.adt.service.UserService; B/@9.a.c
import com.opensymphony.xwork.Action; z>_jC+
P8#;a
/** SVvR]T&_
* @author Joa ?9<byEO%M
*/ [p3)C<;ZC
publicclass ListUser implementsAction{ C/nzlp~
QC+oSb!!?
privatestaticfinal Log logger = LogFactory.getLog <cTusC<
etbB;!6
(ListUser.class); tg%U2+.q
P(N$U^pj
private UserService userService; 6.fahg?E
+{* @36A5A
private Page page; Q=hf,/N
Mq7d*Bgb
privateList users; [;5?=X,LD
e[D'0L
/* >{_`J
* (non-Javadoc) "],amJ
* gwFHp.mE
* @see com.opensymphony.xwork.Action#execute() Gx75EQ2
*/
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publicString execute()throwsException{ TRQX#))B
Result result = userService.listUser(page); lZ^UAFF
page = result.getPage(); Rb_HD
users = result.getContent(); Epm'u[wV
return SUCCESS; neC]\B[Xm
} e<