Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Gi{1u}-0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0_&oMPY
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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 }>tUkXlhJ<
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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 9cj=CuE
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分页支持类: nk-?$'i9q
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java代码: R0m}I5Frs
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package com.javaeye.common.util; +VU,U`W
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import java.util.List; DrB=
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publicclass PaginationSupport { !{ )H
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publicfinalstaticint PAGESIZE = 30; ,:;_j<g`e
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privateint pageSize = PAGESIZE; w>m/c1
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privateList items; ^M,Q<HL
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privateint totalCount; Yoaz|7LS
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privateint[] indexes = newint[0]; { >4exyu6
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privateint startIndex = 0; lYJ]W[!
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public PaginationSupport(List items, int <M 7WWtmx
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totalCount){ R%5\1!Fl=G
setPageSize(PAGESIZE); ';$2j~
setTotalCount(totalCount); KU$.m3A>
setItems(items); Q+uYr-
setStartIndex(0); %=_Iq\lC
} #_Tceq5
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public PaginationSupport(List items, int .Mm8\].
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totalCount, int startIndex){ N4$0ptz#}G
setPageSize(PAGESIZE); 'rz*mR8
setTotalCount(totalCount); #X|'RL($
setItems(items); @AWKEo<7.I
setStartIndex(startIndex); n:; 2Z
} ZT|E1[Q
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public PaginationSupport(List items, int #V~r@,
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totalCount, int pageSize, int startIndex){ *S<>_R 8
setPageSize(pageSize); c%v%U &
setTotalCount(totalCount); /Nxy?g|,
setItems(items); sV{[~U,|
setStartIndex(startIndex); ;O.U-s
} ``zg |h
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publicList getItems(){ Gn&)*qCO
return items; <0Q`:'\.>
} \|wVIi
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publicvoid setItems(List items){ &@{Ba~S
this.items = items; 0y6nMI
} 2MJ0[9
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publicint getPageSize(){ yyBfLPXZ
return pageSize; 18|H
} oIf-s[uH
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publicvoid setPageSize(int pageSize){ 6Zkus20
this.pageSize = pageSize; rTK/WZs8
} unP7("A0D
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publicint getTotalCount(){ JYKaF6bx8
return totalCount; 0oM~e
} }CQ GvH
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publicvoid setTotalCount(int totalCount){ \Mt(9jNK
if(totalCount > 0){ i7Y96]
this.totalCount = totalCount; MiS$Y
int count = totalCount / .D>%-
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pageSize; |} .Y&1@U
if(totalCount % pageSize > 0) \{abyi;
count++; 2<|+h=
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indexes = newint[count]; du`],/ 6
for(int i = 0; i < count; i++){ N}zQ)]xz+r
indexes = pageSize * lq+FH&
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i; v{&cgod
} u:"mq.Q
}else{ 8 =J6{{E
this.totalCount = 0; b9`MUkGGd
} $t[`}I
}
} Ql#:Rx>b
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publicint[] getIndexes(){ id GM%Faur
return indexes; UB(Q &U_
} |67<h5Q1
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publicvoid setIndexes(int[] indexes){ TRX; m|
this.indexes = indexes; @cSz!E}
} -1Tws|4gc
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publicint getStartIndex(){ S'2B
return startIndex; D4;V8(w=#
} ]\*g/QV
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publicvoid setStartIndex(int startIndex){ Z2hRTJJ[A
if(totalCount <= 0) NDCZc_
this.startIndex = 0; Hza{"I*^
elseif(startIndex >= totalCount) ?%B%[u
this.startIndex = indexes ZZ?=^g
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[indexes.length - 1]; -F@Rpfrj_#
elseif(startIndex < 0) /]iv9e{uh(
this.startIndex = 0; Rq9v+Xq2
else{ UiF ?Nx~
this.startIndex = indexes nv@$'uQRp
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[startIndex / pageSize]; LlX 7g_!
} T%?<3/Ev!
} #![b9~%WTh
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publicint getNextIndex(){ Cc/?-0a2!
int nextIndex = getStartIndex() + 3`Y
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pageSize; -=O9D-x=
if(nextIndex >= totalCount) `'.u$IBW
return getStartIndex(); )!){4c/
else l9?]t;
return nextIndex; !,INrl[
} ~h tV*R
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publicint getPreviousIndex(){ *W%HTt"N
int previousIndex = getStartIndex() - l`fjz-eE
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pageSize; <~vamim#K
if(previousIndex < 0) F;5.nKo
return0; :v8j3=
else %/-Z1Nv*#
return previousIndex; >*B/Wy
} m3\lm@`)O
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} r4A%`sk@
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抽象业务类 >mi%L3Pk
java代码: wp$CJ09f*
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/** "JKrbgN@;L
* Created on 2005-7-12 T&X*[kP
*/ M($dh9 A_
package com.javaeye.common.business; !+=jD3HTJ
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import java.io.Serializable; N1zB;-0t
import java.util.List; HG5|h[4Gt
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import org.hibernate.Criteria; ]aXCi"fMs
import org.hibernate.HibernateException; wQlK[F]!>
import org.hibernate.Session; L&][730
import org.hibernate.criterion.DetachedCriteria; z?Hvh
import org.hibernate.criterion.Projections; _<=U.T`
import b~y1'|}g
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org.springframework.orm.hibernate3.HibernateCallback; 9{^:+r
import ePP-&V"`"
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org.springframework.orm.hibernate3.support.HibernateDaoS 4\Mh2z5
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upport; <RKh%4#~
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import com.javaeye.common.util.PaginationSupport; blk~r0.2
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public abstract class AbstractManager extends YFy5>*W
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HibernateDaoSupport { :S{[^-"
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privateboolean cacheQueries = false; @G~T&6E!
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privateString queryCacheRegion; wk<QYLEk
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publicvoid setCacheQueries(boolean JGHQ_AI
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cacheQueries){ ?r"m*fY%
this.cacheQueries = cacheQueries; V+W,#5
} 1b-4wonQd
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publicvoid setQueryCacheRegion(String &JVe-.
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queryCacheRegion){ K!lGo3n]
this.queryCacheRegion = A=Q"IdK
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queryCacheRegion; h?p&9[e`
} @D[jUC$E
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publicvoid save(finalObject entity){ Q
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getHibernateTemplate().save(entity); DO'$J9;*
} oQBfDD0
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publicvoid persist(finalObject entity){ #f5-f
getHibernateTemplate().save(entity); >t.2!Z_RQ
} 5lu620o
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publicvoid update(finalObject entity){ Mmq{]q~At
getHibernateTemplate().update(entity); Ie`kzssM
} H^Ik FEVs
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publicvoid delete(finalObject entity){ P#Z$+&)b)s
getHibernateTemplate().delete(entity); lBvQ?CJ<y
} .ZJt
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publicObject load(finalClass entity, ZXsm9
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finalSerializable id){ KA#4iu{
return getHibernateTemplate().load m/5:-xL31
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(entity, id); O%AQ'['
} f`*Ip? V-
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publicObject get(finalClass entity, CP)x;
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finalSerializable id){ 3(Kj|u
return getHibernateTemplate().get S^HuQe!#
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(entity, id); 4E}]>
} r5xu#%hgp;
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publicList findAll(finalClass entity){ j)?I]j/
return getHibernateTemplate().find("from iqig~fjK~
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" + entity.getName()); Cp7 EJr~
} eNY$N_P
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publicList findByNamedQuery(finalString 2~AGOx
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namedQuery){ ^n"ve2
return getHibernateTemplate ~T7\lJ{%G
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().findByNamedQuery(namedQuery); ?*zRM?*
} J 6U3}SO=y
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publicList findByNamedQuery(finalString query, ev7Y^
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finalObject parameter){ Y-hGHnh]'
return getHibernateTemplate a02@CsH
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().findByNamedQuery(query, parameter); BaIH7JLZ8
} sNZ{OD+
+]*4!4MK6
publicList findByNamedQuery(finalString query, WUkx v*
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finalObject[] parameters){ dU+28
return getHibernateTemplate tJy6\~
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().findByNamedQuery(query, parameters); $rD&rsx6
} N%'=el4L
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publicList find(finalString query){ '\Z54$
return getHibernateTemplate().find cd)yj&:?Bt
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(query); O+A/thI%*S
} R_eKKi@VH
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publicList find(finalString query, finalObject 6;i]v|M-
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parameter){ OV8Y)%t"
return getHibernateTemplate().find q$7WZ+Y\
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(query, parameter); fmILkXKz
} jXB<"bw
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public PaginationSupport findPageByCriteria {SVd='!V
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(final DetachedCriteria detachedCriteria){ +K,]#$k
return findPageByCriteria P#]%C
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); IFYGl
} G]X72R?g
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public PaginationSupport findPageByCriteria EH<rUv63
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(final DetachedCriteria detachedCriteria, finalint gF,9Kv~
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startIndex){ #?-2f{
return findPageByCriteria . S4Xw2MS
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(detachedCriteria, PaginationSupport.PAGESIZE, MX2Zm
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startIndex); NPF"_[RoeV
} BWV)>
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public PaginationSupport findPageByCriteria i;>Yx#
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(final DetachedCriteria detachedCriteria, finalint U0G(
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pageSize, E-\Wo3
finalint startIndex){ E9JxntX
return(PaginationSupport) _0p8FhNt
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getHibernateTemplate().execute(new HibernateCallback(){ yU]NgG=z:-
publicObject doInHibernate O
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(Session session)throws HibernateException { KfD=3h=
Criteria criteria = 9bd $mp
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detachedCriteria.getExecutableCriteria(session); wxU@M1w}
int totalCount = hF|N81T
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((Integer) criteria.setProjection(Projections.rowCount LPO:Ka
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()).uniqueResult()).intValue(); f*U3s N^y
criteria.setProjection %>u(UmFO
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(null); U7i WYdt$
List items = Hz39v44
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criteria.setFirstResult(startIndex).setMaxResults }}L :6^
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(pageSize).list(); ~~,] b
PaginationSupport ps = (Ubz@s^
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new PaginationSupport(items, totalCount, pageSize, D>neY9
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startIndex); C],"va
return ps; .)J7 \z8m
} ;Qe-y|>
}, true); wj$l 093
} @$o.Z;83`r
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public List findAllByCriteria(final fg"]4&`j-
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DetachedCriteria detachedCriteria){ jFS])",\i
return(List) getHibernateTemplate W6STjtT3P
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().execute(new HibernateCallback(){ Y~vyCU5nWR
publicObject doInHibernate W.u+R?a=
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(Session session)throws HibernateException { x~3N})T5
Criteria criteria = tgk] sQY
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detachedCriteria.getExecutableCriteria(session); nX
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return criteria.list(); !V/Vy/'`*
} vl1`s
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}, true); cP8g.+
} Xm#rkF[,
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public int getCountByCriteria(final $#2zxpr,
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DetachedCriteria detachedCriteria){ ^!a4!DGVT
Integer count = (Integer) 2;&K*>g&.
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getHibernateTemplate().execute(new HibernateCallback(){ Gs`[\<;LI
publicObject doInHibernate ",&^ f
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(Session session)throws HibernateException { Z9S5rPHEL
Criteria criteria = e'"2yA8dh"
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detachedCriteria.getExecutableCriteria(session); ,_+Gb
return gl.uDO%.
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criteria.setProjection(Projections.rowCount S(*u_
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()).uniqueResult(); b3j?@31AD
} $qndG,([F
}, true); 04o>POR
return count.intValue(); K14FY2"
} u?Pec:3%
} 3:H[S_q
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用户在web层构造查询条件detachedCriteria,和可选的 /2s=;tA1
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 kD}w5 U
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PaginationSupport的实例ps。 Dt#( fuk#
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ps.getItems()得到已分页好的结果集 /w|!SZB
ps.getIndexes()得到分页索引的数组 V=
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ps.getTotalCount()得到总结果数 5)@UpcjUA
ps.getStartIndex()当前分页索引 #3~ #`&
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 o54/r#~fi
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 eE=}^6)(*
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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 ZBY*C;[)*P
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一下代码重构了。 jV
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我把原本我的做法也提供出来供大家讨论吧: y"I8^CA
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首先,为了实现分页查询,我封装了一个Page类: hD*83_S
java代码: w%2|Po5
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/*Created on 2005-4-14*/ uUIjntSF(
package org.flyware.util.page; 1#w'<}h#U
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/** E[=#Rw!*
* @author Joa YqQAogyh
* O)FkpZc@9c
*/ evQk,;pIm
publicclass Page { =JW.1;
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/** imply if the page has previous page */ ~[Fh+t(Y
privateboolean hasPrePage; QAxR'.d
Efa3{
7>{
/** imply if the page has next page */ ABIQi[A
privateboolean hasNextPage; LlF|VR&P.
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/** the number of every page */ _xz>O[unf
privateint everyPage; 'pa8h L
h
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/** the total page number */ ^[=1J
privateint totalPage; >gTQD\k:D
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/** the number of current page */ s$3WJ'yr
privateint currentPage; e~1$x`DH
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/** the begin index of the records by the current }C'h<%[P
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query */ ugy:^U
privateint beginIndex; c#L.I
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/** The default constructor */ !h.bD/?K
public Page(){ 3E$h
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} gk^`-`P
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/** construct the page by everyPage @wTRoMHPQ
* @param everyPage %7SGQE#W_~
* */ 8eDKN9kq
public Page(int everyPage){ Y![//tg
this.everyPage = everyPage; E/Adi^
} m^%Xl@V:c-
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/** The whole constructor */ q +*>T=k
public Page(boolean hasPrePage, boolean hasNextPage, nK>D& S_!
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int everyPage, int totalPage, d$<1Ma}
int currentPage, int beginIndex){ 15Vo_
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this.hasPrePage = hasPrePage; 'Im&&uSkr
this.hasNextPage = hasNextPage; Epm%/ {sHV
this.everyPage = everyPage; &B@qb?UE1
this.totalPage = totalPage; )#0Llx!
this.currentPage = currentPage; wpepi8w,
this.beginIndex = beginIndex; $E35W=~)
} ;Ebpf J
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/** VCCG_K9'
* @return yiAusl;
* Returns the beginIndex. Zoyo:vv&
*/ jx-8%dxtZ
publicint getBeginIndex(){ N,?D<NjXl
return beginIndex; dY$jg
} *rmwTD"
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/** uTIl} N
* @param beginIndex tg%C>O
* The beginIndex to set. nTH!_S>b(Y
*/ tRzo}_+N
publicvoid setBeginIndex(int beginIndex){ #e5*Dr8
this.beginIndex = beginIndex; -) \!@n0
}
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/** r57rH^Hc
* @return _^Lg}@t
* Returns the currentPage. 2@+MT z
*/ %q5iy0~P
publicint getCurrentPage(){ 5%%A2FrB.S
return currentPage; OJ4-p&1
} 5c+7c@.
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/** !Z`xwk"!
* @param currentPage `^1&Qz>
* The currentPage to set. tX.{+yyU
*/ !#Hca
publicvoid setCurrentPage(int currentPage){ oQ_n:<3X
this.currentPage = currentPage; cwKOE?!
} -nKBSls
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/** Ykt(%2L
* @return n+;PfQ|
* Returns the everyPage. Bl8&g]dk
*/ ~zA{=|I2
publicint getEveryPage(){
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return everyPage; A}Gj;vaw
} !Knv/:+
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/** ||vQW\g
* @param everyPage EL=}xug,?
* The everyPage to set. ?$\y0lHw/7
*/ O-K!Bv^
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publicvoid setEveryPage(int everyPage){ uH?lj&
this.everyPage = everyPage; 4,g3 c
} #$(wfb9
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/** |
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* @return 2\1\Jn#q
* Returns the hasNextPage. tf@x}
*/ q'p>__Ox
publicboolean getHasNextPage(){ dwt<s[k
return hasNextPage; V7
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} -hP-w>
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/** bUi@4S
* @param hasNextPage 3`aJ"qQE
* The hasNextPage to set. JI}p{yI
*/ DLrG-C33
publicvoid setHasNextPage(boolean hasNextPage){ 6lc/_&0
this.hasNextPage = hasNextPage; &Jw4^ob
} lt&30nf=
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/** ,w/f:-y
* @return 'd@Vusq}2
* Returns the hasPrePage. 7J%v""\1!
*/ 8E!I9z
publicboolean getHasPrePage(){ TAt9+\'
return hasPrePage; ,`JXBI~
} oFeflcSz
NX*9nwp^
/** Eh)VU_D
* @param hasPrePage "rA:;ntz
* The hasPrePage to set. fJ3qL#'
*/ YMx
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publicvoid setHasPrePage(boolean hasPrePage){ ;Q.g[[J/p
this.hasPrePage = hasPrePage; {@u}-6:wAT
} S hM}w/4
[+st?;"GF
/** s=nE'/q1|
* @return Returns the totalPage. |KFWW
* \'L6m1UZ%
*/ D{,B[5
publicint getTotalPage(){ " lf_`4
return totalPage; PHa#;6!5
} V8xv@G{;
'c<@SVF{Zz
/** #:68}f"$
* @param totalPage :;XHA8
* The totalPage to set. ;v6e2NacM'
*/ Eu
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publicvoid setTotalPage(int totalPage){ XjwTjgL<
this.totalPage = totalPage; `<>8tZS9"
} A{E0 a:v
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} Xklp6{VH9
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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 FK#>E[[
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个PageUtil,负责对Page对象进行构造: ~::gLm+f
java代码: 9&W\BQ
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/*Created on 2005-4-14*/ ,U'Er#U
package org.flyware.util.page; 'U)~|(\i
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import org.apache.commons.logging.Log; +WwQ!vWWd
import org.apache.commons.logging.LogFactory; \Rp)n=|
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/** 5.|rzk>
* @author Joa _TB\@)\
* m`9)DsR
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*/ %'* |N[
publicclass PageUtil { YS{
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privatestaticfinal Log logger = LogFactory.getLog 2+GF:[$
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(PageUtil.class); hP,1;`[1
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/** ?k_=?m
* Use the origin page to create a new page _'AIXez7q
* @param page !*|CIxk(
* @param totalRecords y::;e#.
* @return ORx,n7-
*/ igz:ek`
publicstatic Page createPage(Page page, int Sjr(e}*
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totalRecords){ TL7-uH
return createPage(page.getEveryPage(), ^@)/VfVg
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page.getCurrentPage(), totalRecords); )hQNIt3o_
} i%*x7zjY{
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/** z4-AOTo2y
* the basic page utils not including exception {=g-zsc]K
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handler 8d)F#
* @param everyPage [1nI%/</>
* @param currentPage fJE ki>1
* @param totalRecords ooZ7HTP|
* @return page X\%],"9%
*/ wOi>i`D&
publicstatic Page createPage(int everyPage, int ydns_Z
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currentPage, int totalRecords){ _-8,}F}W#s
everyPage = getEveryPage(everyPage); !Q7
currentPage = getCurrentPage(currentPage); jSYj+k
int beginIndex = getBeginIndex(everyPage, @/0aj
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t
currentPage); K.z}%a
int totalPage = getTotalPage(everyPage, 9D#PO">|
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totalRecords); *h =7:*n
boolean hasNextPage = hasNextPage(currentPage, x(b&r g.-0
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totalPage); ~4`wfOvO
boolean hasPrePage = hasPrePage(currentPage); 2%8N<GW.F
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returnnew Page(hasPrePage, hasNextPage, 4UL-j
everyPage, totalPage, I$mOy{/#
currentPage, Ew:JpMR
XbH X,W$h
beginIndex); _u:#2K$
} IWT##']G
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privatestaticint getEveryPage(int everyPage){ ,OasT!Sr
return everyPage == 0 ? 10 : everyPage; sG VC+!E
} MJg^
QVM
E>g'!
privatestaticint getCurrentPage(int currentPage){ zWY6D4
return currentPage == 0 ? 1 : currentPage; @W @L%<
} g{J3Ba
B)-S@.u
privatestaticint getBeginIndex(int everyPage, int T]vD ,I+
'[-/Xa['
currentPage){ ttw@nv%
@
return(currentPage - 1) * everyPage; yQx>h6
} ;:!LAe
2hpx%H
privatestaticint getTotalPage(int everyPage, int u\E.H5u27
16Xwtn72
totalRecords){ ]Pd*w`R
int totalPage = 0; 1OGlD+f
NfO0^^"
if(totalRecords % everyPage == 0) uyA9`~p=#
totalPage = totalRecords / everyPage; 2)8lJXM$L
else k{bba=<
totalPage = totalRecords / everyPage + 1 ; q/3}8BJ
8EE7mEmLH
return totalPage; 3Q ]MT
} q@!:<Ra,){
b]Y,& 8}[+
privatestaticboolean hasPrePage(int currentPage){ )T3wU~%
return currentPage == 1 ? false : true; OKU P
} ;% !?dH6
;dWqMnV
privatestaticboolean hasNextPage(int currentPage, ;,A\bmC
B#DV<%GPl
int totalPage){ 7uDUZdJy
return currentPage == totalPage || totalPage == vn_avYwiy
@!MbPS
0 ? false : true; foFn`?LF
} aH$~':[93
wd]Yjr#%Ii
soohyK8
} @fK`l@K
9BY b{<0tS
UB1/FM4~
W#wM PsB
<h}?0NA4
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。 5[R}MhLZ
TB[vpTC9)
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 OiOL4}5(
wTW"1M
做法如下: "L)pH@)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ES~]rPVS
}n=NHHtJ
的信息,和一个结果集List: f65Sr"qB3
java代码: VO`A
) )F.|w
O>Sbb2q?"
/*Created on 2005-6-13*/ Kaa*;T![
package com.adt.bo; =,'Z6?%p
gMvvDP!Wp
import java.util.List; pE<' '`
F,zJdJ
import org.flyware.util.page.Page; |<V{$),k
0%t|?@HoN
/** 3q>"#+R.t
* @author Joa FX^E |
*/ [Ok8l='
publicclass Result { >H1d9y+Z
s`B'vyoaa
private Page page; kMo)4Xp
_e3'f:
private List content; $!f$R`R^Q\
h$&XQq0T
/** }rE|\p>
* The default constructor GEA;9TU|V
*/ M($},xAvDU
public Result(){ >
95Cs`>d
super(); (`NRF6'&1L
} [jw o D
wl%1B64
/** LJy'wl
* The constructor using fields 54{"ni2a
* Cg
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* @param page |- fx
0y
* @param content 6S<$7=$=
*/ 6bGD8;
public Result(Page page, List content){ Kv]6 b2HT
this.page = page; +XE21hb
this.content = content; 6!nb)auVi
} <@A^C$g
"!tB";n
/** 3$8}%?i
* @return Returns the content. ="DgrH
*/ ttnXEF
publicList getContent(){ 3(:mRb}
return content; v,+@
U6i
} C\^K6,m5
I/aAx.q
/** [f0HUbPX
* @return Returns the page. }'W^Ki$
*/ |
#Pc
e
public Page getPage(){ qM0MSwvC=
return page; +joE
} i[pf*W0g
/aqN`
/** EVFfXv^
* @param content (UZ*36@PJx
* The content to set. u-_$?'l;~
*/ 7gwZ9Fob
public void setContent(List content){ 1l_}O1
this.content = content; -G;1U
} ,#T3OA!c**
w8
$Qh%J'<
/** 6iG<"{/U5
* @param page ib_Gy77Os
* The page to set. {*<C!Qg
*/
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publicvoid setPage(Page page){ ,NEs{!
T
this.page = page; 3kCbD=yF
} Y14R"*t~
} Wu( 8G
`tG_O
s
vb4uvY
Rda1X~-g
j>xVy]v= |
2. 编写业务逻辑接口,并实现它(UserManager, fWyDWU
:dN35Y] a
UserManagerImpl) !&O/7ywe
java代码: A#X.c=
V(u2{4gZ
C|\^uR0
/*Created on 2005-7-15*/ d~jtWd|?
package com.adt.service; aT#{t{gkA
hPz
df*(8
import net.sf.hibernate.HibernateException; S=,1}
XZ
J'yN' 0
import org.flyware.util.page.Page; 'w[d^L
$`{q[ {
import com.adt.bo.Result; {@5WeWlz~
cWO
)QIE
/** TRLeZ0EC
* @author Joa t`T\d\
*/ "g%:#'5
publicinterface UserManager { cqY.^f.
xm|4\H&Bg
public Result listUser(Page page)throws yH%+cmp7
sBtG}Mo)
HibernateException; =t$mbI
SU
O;
} `u~
_qt;{,t
s}#[*WOc
=jIT"rk
V`,[=u?c
java代码: n>:c}QAJH
8EG8!,\I
Cw[Od"B\?U
/*Created on 2005-7-15*/ #A/J^Ko
package com.adt.service.impl; tH,K\v`f
(1SO;8k\
import java.util.List; _8li4;F
Mc7 <[a
import net.sf.hibernate.HibernateException; |M<.O~|D6}
h:jI
import org.flyware.util.page.Page; ZqbM%(=z(`
import org.flyware.util.page.PageUtil; M.:@<S
`s83rhs`!
import com.adt.bo.Result; d =(Yl r
import com.adt.dao.UserDAO; $^=jPk]+
import com.adt.exception.ObjectNotFoundException; @@/'b'
import com.adt.service.UserManager; mXU?+G0
aI{@]hCo
/** N(-%"#M$
* @author Joa 'RV\}gqZ
*/ qa$[L@h>
publicclass UserManagerImpl implements UserManager { nUud?F^_
jaO#><f
private UserDAO userDAO; _c9
WWp?
!qXq
y}?w
/** GQ-e$D@SfB
* @param userDAO The userDAO to set. 0|s$vqc
*/ j+13H+dN
publicvoid setUserDAO(UserDAO userDAO){ c+b:K
this.userDAO = userDAO; DA MpR3
} h w ;d m
*T>#zR{
/* (non-Javadoc) ;8L+_YCa
* @see com.adt.service.UserManager#listUser ADyNNMcx
Tt <-<oyU.
(org.flyware.util.page.Page) _WDBG
*/ 0J:U\S
public Result listUser(Page page)throws <[3lV)~t
UQ$\
an'
HibernateException, ObjectNotFoundException { ;%rs{XO9
int totalRecords = userDAO.getUserCount(); TFJ{fLG
if(totalRecords == 0) oj^5G
]_<
throw new ObjectNotFoundException KSgQ:_u4}
X[~f:E[1J
("userNotExist"); *]:G7SW{
page = PageUtil.createPage(page, totalRecords); N}+B:l]Qy
List users = userDAO.getUserByPage(page); K*Nb_|~
returnnew Result(page, users); >|_gT%]5
} y13CR2t6
D)*_{
} qN1e{T8u
\9>g;qPg}
_yxe2[TD
f`u5\!}=!
nXM9Px!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lNh=>DPu
]*g ss'N
询,接下来编写UserDAO的代码: A|
gs Uh
3. UserDAO 和 UserDAOImpl: !8
wid&
java代码: K{=r.W
[I++>4
7dufY
} }
/*Created on 2005-7-15*/ S&
, Ju%
package com.adt.dao; c+E//X|
SrQ4y`?
import java.util.List; (}*\ {
L_
Xn,
import org.flyware.util.page.Page; Lt;.Nw
%/tGkS6
import net.sf.hibernate.HibernateException; ^^4K/XBve
PUQ_w
/** , `[Z`SUk`
* @author Joa bG5^h
*/ T.R>xd`9
"
publicinterface UserDAO extends BaseDAO { taWirqd9
8"?Vcw&
publicList getUserByName(String name)throws VGTeuu5i
HC9vc,Fp
HibernateException; M]6w^\4j9
c]%;^)
publicint getUserCount()throws HibernateException; @o4z3Q@
Xa{~a3Wy
publicList getUserByPage(Page page)throws 9&[)(On74
?;:9
W
HibernateException; !~lVv&YO
d5w_[=9U
} r%Q8)nEo
.^[fG59
L;.VEz!
]b0zkoD9<
a!c/5)v(
java代码: IKMsY5i
l#2r.q^$|
*tTP8ZCQ[
/*Created on 2005-7-15*/ r!=]Q}`F
package com.adt.dao.impl; lgCHGv2@
Vr&el
import java.util.List; h"VpQhi
dAYI D E
import org.flyware.util.page.Page; 'WKu0Yi^'
"B|nh d
import net.sf.hibernate.HibernateException; dxzvPgi?
import net.sf.hibernate.Query; 26\HV
p<of<YU)
import com.adt.dao.UserDAO; ]Wy^VcqX
ql{^"8x
/** =R8f)UQYx
* @author Joa (ZE%tbm2
*/ $Q`yNEc
public class UserDAOImpl extends BaseDAOHibernateImpl -,K*~z.l
,GdxUld
implements UserDAO { E<D+)A
u4Y6B
]Q
/* (non-Javadoc) a-T*'F
* @see com.adt.dao.UserDAO#getUserByName O tXw/
[ E$$nNs
(java.lang.String) zVp[YOS&c
*/ jGk7=}nw
publicList getUserByName(String name)throws o-\ok|,)#j
"?oo\op
HibernateException { (,- 5(fW
String querySentence = "FROM user in class ~u_K&X
17V\2=Io
com.adt.po.User WHERE user.name=:name"; F`YFo)W
Query query = getSession().createQuery X0^zw^2W
X)FL[RO%q
(querySentence); _N>wzkJ
query.setParameter("name", name); kN'|,eKH4
return query.list(); 7j@^+rkr3f
} LFEp
/`7 I K
/* (non-Javadoc) E0sbU<11
* @see com.adt.dao.UserDAO#getUserCount() "_nX5J9
*/ pj!k|F9
publicint getUserCount()throws HibernateException { W@:^aH
int count = 0; ]h #WkcXQ
String querySentence = "SELECT count(*) FROM GIl:3iB49
|RHO+J
user in class com.adt.po.User"; Bv;I0i:_
Query query = getSession().createQuery |x1$b7
QDIsC
(querySentence); xT{TVHdU
count = ((Integer)query.iterate().next '4af
],
}U2[?
()).intValue(); .LX?VD
return count; euRCBzc
} /'-:=0a
::4"wU3t
/* (non-Javadoc) K&j'c
* @see com.adt.dao.UserDAO#getUserByPage +V2C}NQ5R
rDpe_varA
(org.flyware.util.page.Page) f?2zLE>u
*/ vg+r?4Q3
publicList getUserByPage(Page page)throws X tJswxw`K
^OHZ767v
HibernateException { 'jh2**i 34
String querySentence = "FROM user in class zSEr4^Dk4
V8-4>H}Cb/
com.adt.po.User"; YH6snC$u
Query query = getSession().createQuery *}+R{
Sv.KI{;v$
(querySentence); M#=Y~PU
query.setFirstResult(page.getBeginIndex()) ]MC/t5vC u
.setMaxResults(page.getEveryPage()); 6o$Z0mG
return query.list(); iYkRo>3!QX
} "EJ\]S]$X
OZ eiHX!
} 8r2XGR
UP\8w#~
{;U} :Dx
w+Ad$4Pf"
G"}qV%"6"
至此,一个完整的分页程序完成。前台的只需要调用 -s{R/ 6:
[Dnusp7e
userManager.listUser(page)即可得到一个Page对象和结果集对象 (&q@~
dJ
w#W5}i&x
的综合体,而传入的参数page对象则可以由前台传入,如果用 [fd~nD#.
}'u3U"9)
webwork,甚至可以直接在配置文件中指定。 .8-PB*vb
O:2 #_
下面给出一个webwork调用示例: Tsu\oJ[
java代码: b21}49bHN
k"t>He
C,[L/!
/*Created on 2005-6-17*/ P~&O4['<
package com.adt.action.user; TLy;4R2Nn
&q.)2o#Q.
import java.util.List; O ,l\e3;
&u&2D$K,tp
import org.apache.commons.logging.Log;
}K?F7cD
import org.apache.commons.logging.LogFactory; )sqaR^
import org.flyware.util.page.Page; MY&<)|v\
TV<Aj"xw
import com.adt.bo.Result; pH^ z
import com.adt.service.UserService; b7Yq_%+
import com.opensymphony.xwork.Action; %cS#+aK6M'
aWdUuid
/** nZe\5`
* @author Joa $$42pb.
*/ 6!@0VI&P
publicclass ListUser implementsAction{ tAaYL
\~
JL@F~U9
privatestaticfinal Log logger = LogFactory.getLog Lg8]dBXu
D4d]3|/T
(ListUser.class); .Xi2G@D
T)`gm{T
private UserService userService; #uB[&GG}W
Yi[4DfA
private Page page; .a {QA
H%FM
privateList users; +5#x6[
!TGr .R
/* /=bSt
* (non-Javadoc) cY{I:MA+h@
* Q^nG0<q+
* @see com.opensymphony.xwork.Action#execute() [@g ~
*/ " l.!Ed
publicString execute()throwsException{ f7.m=lbe
Result result = userService.listUser(page); P7'M],!9w
page = result.getPage(); >)4.$#H
users = result.getContent(); )4PB<[u
return SUCCESS; W.IH#`-9E
} cFw3Iw"JJ
B+|IZoR
/** 2f `&WUe
* @return Returns the page. ^+EMZFjg(
*/ g2A"1w<-AH
public Page getPage(){ m.!wsw
return page; #o~[1K+Yq
} iFSJ4 W(
*g*VCO
/** WBa /IM
* @return Returns the users. %
^e@`0L
*/ 3<+z46`?
publicList getUsers(){ z[*zuo
return users; KA?v.s
} G<|:605
ssPI$IRg!
/** QOd!]*W`?m
* @param page 'g2vX&=$A
* The page to set. s_TD4~
$
*/ XYMxG:
publicvoid setPage(Page page){ FQ1arUOFW,
this.page = page; ve6x/ PD
} 0Lx3]"v
?H<~ac2e
/** } +1'{B"I
* @param users sx:Hv1d
* The users to set. 3Mur*tj#
*/ ERp{gB2U?
publicvoid setUsers(List users){ w?*jdwh,'
this.users = users; ^zHRSO
} CGkI\E
;|;iCaD a+
/** 1b8c67j[
* @param userService Jb9F=s+
* The userService to set. ~+=E"9Oo
*/ 4Mi~1iZj
publicvoid setUserService(UserService userService){ !M,h79NM
this.userService = userService; qZ&