Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 E,nC}f
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .4"9o%
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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 AoEG%nT
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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 ui,#AZQ#{4
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分页支持类: !' No5
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java代码: /u
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package com.javaeye.common.util; BOLG#}sm
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import java.util.List; D84`#Xbi
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publicclass PaginationSupport { `<h}Ygo>k/
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publicfinalstaticint PAGESIZE = 30; _W4i?Bde
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privateint pageSize = PAGESIZE; Kv[,!P"Y
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privateList items; B1oy,'
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privateint totalCount; iXc-_V6
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privateint[] indexes = newint[0]; =~% B}T
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privateint startIndex = 0; h5G>FPM-=
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public PaginationSupport(List items, int ?]081l7cd
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totalCount){ sT9P
setPageSize(PAGESIZE); 93yJAao9
setTotalCount(totalCount); 3VbQDPG
setItems(items); ip4:px-
setStartIndex(0); C26PQGo#$
} ^.F@yo2}
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public PaginationSupport(List items, int ]BU,*YaB
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totalCount, int startIndex){ &3mseU
setPageSize(PAGESIZE); Pq~"`-h7:
setTotalCount(totalCount); .9WJ/RKZ\D
setItems(items); UK2Y<\vD
setStartIndex(startIndex); 5@"&%8oeq0
} b+\jFGC%6=
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public PaginationSupport(List items, int P$Y<
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totalCount, int pageSize, int startIndex){ FS r`Y
setPageSize(pageSize); ^9o;=!D!9
setTotalCount(totalCount); K3&v6 #]
setItems(items); VY$hg
setStartIndex(startIndex); ;8;nY6Ie
} g6$X {
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publicList getItems(){ *TA${$K
return items; !mrB+<:
} ~wIVw}
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publicvoid setItems(List items){ Qw.""MLmN8
this.items = items; dRyK'Xr
} 0O?B!Jr]RM
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publicint getPageSize(){ w*r.QzCu,5
return pageSize; X~Uvh8O
} w-R>gdm
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publicvoid setPageSize(int pageSize){ l}%!&V0
this.pageSize = pageSize; ?@l9T)fF
} EXg\a#4['
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publicint getTotalCount(){ to^ &:
return totalCount; 3@?#4]D{'
} Ob?>zsx
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publicvoid setTotalCount(int totalCount){ I@a7AuOw
if(totalCount > 0){ zTBr<:
this.totalCount = totalCount; 9j:t}HV
int count = totalCount / <wxI>T }b
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pageSize; H=z@!rJc.
if(totalCount % pageSize > 0) mQBq-;
count++; 3Ec5:Caz
indexes = newint[count]; m,$oV?y>j
for(int i = 0; i < count; i++){ Ck2O?Ne
indexes = pageSize * uh%%MhTjv
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i; q"'^W<i
} zuWj@YG\.
}else{ xj)*K%re
this.totalCount = 0; ,:G.V
} 3k5OYUk
} "8J$7g@n@
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publicint[] getIndexes(){ :#"gQ^YNp
return indexes; /}r%DND'
} \y{Bnp5h
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publicvoid setIndexes(int[] indexes){ HQK%Y2S
this.indexes = indexes; gAC}
} !E,$@mvd
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publicint getStartIndex(){ g1JD8~a
return startIndex; NTuS(7m
} BQmg$N,F
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publicvoid setStartIndex(int startIndex){ U2=5Nt5
if(totalCount <= 0) wt[MzpR P
this.startIndex = 0; %F9%t
elseif(startIndex >= totalCount) zFqH)/
this.startIndex = indexes &4sUi K"
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[indexes.length - 1]; +,9I3Dq
elseif(startIndex < 0) xvQJTRk
this.startIndex = 0; 3_B .W
else{ n`? j.
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this.startIndex = indexes sAfSI<L_
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[startIndex / pageSize]; ;#P@(ZVT
} "X g@X5BG
} J2Ocf&y;
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publicint getNextIndex(){ SJ^.#^)
int nextIndex = getStartIndex() + +|).dm
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pageSize; {N[IjY
if(nextIndex >= totalCount) 9kuL1tcY
return getStartIndex(); XL >Vwd
else r5Jy( ~
return nextIndex; bv5,Yk
} ;hJTJMA6/6
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publicint getPreviousIndex(){ ^IOf%
int previousIndex = getStartIndex() - sbZ)z#Tr
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pageSize; ` QXO+'j4
if(previousIndex < 0) t8\F7F P
return0; )\l}i%L:
else $SRpFz5y$
return previousIndex; ]
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} GN?^7kI
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} d3_aFsQ
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抽象业务类 ,>V|%tD'
java代码: ++-HdSHY
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/** "n,">
* Created on 2005-7-12 4 FW~Y
*/ %N7b
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package com.javaeye.common.business; v*<hE>J0
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import java.io.Serializable; |sMRIW,P
import java.util.List; SGre[+m~m
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import org.hibernate.Criteria; /jaTH_Q),:
import org.hibernate.HibernateException; )~v`dwKj;
import org.hibernate.Session; ;"-(QE?Mv
import org.hibernate.criterion.DetachedCriteria; .C$S
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import org.hibernate.criterion.Projections; wUW^
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import rS\j9@=Y4
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org.springframework.orm.hibernate3.HibernateCallback; 0z #'=XWk
import ' 7+x,TszI
t*m04* }
org.springframework.orm.hibernate3.support.HibernateDaoS CeSr~Ikg|
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upport; Hgu$)yhlj
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import com.javaeye.common.util.PaginationSupport; g&!UaJ[#9
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public abstract class AbstractManager extends C=IT`iom1C
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HibernateDaoSupport { ?OW
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privateboolean cacheQueries = false; i#Io;
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privateString queryCacheRegion; Yrs7F.Y"
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publicvoid setCacheQueries(boolean JGOry \
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cacheQueries){ %OB:lAeJ
this.cacheQueries = cacheQueries; 1PpZ*YK3z
} V
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publicvoid setQueryCacheRegion(String <k!M+}a 9V
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queryCacheRegion){ 2-728
this.queryCacheRegion = ukpbx;O:hc
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queryCacheRegion; HC(Vu
} C-E~z{
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publicvoid save(finalObject entity){ 83K)j"!<X
getHibernateTemplate().save(entity); [Gop-Vi/~
} 0uV3J
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publicvoid persist(finalObject entity){ v/*}M&vo
getHibernateTemplate().save(entity); h/ 5|3
} Z<L}ur
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publicvoid update(finalObject entity){ ;$,=VB:'
getHibernateTemplate().update(entity); [~*5uSG
} 1AQVj]#S
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publicvoid delete(finalObject entity){ 0b6jGa
getHibernateTemplate().delete(entity); G2qv)7{l2
} O42`Z9oK
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publicObject load(finalClass entity, U;`C%vHff
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finalSerializable id){ waI?X2
return getHibernateTemplate().load [p3{d\=*?
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(entity, id); })W9=xO~
} <|Srbs+
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publicObject get(finalClass entity, (rqc_ZU5
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finalSerializable id){ `ppyCUX
return getHibernateTemplate().get 0t*e#,y
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(entity, id); K8#MQR2@
} <}7 5Xo
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publicList findAll(finalClass entity){ LNp{lC
return getHibernateTemplate().find("from g)$/'RB
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" + entity.getName()); "uCO?hv0
} -Vg(aD
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publicList findByNamedQuery(finalString R!i\-C1 S
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namedQuery){ fF6bEJl3
return getHibernateTemplate /]j^a:#"6t
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().findByNamedQuery(namedQuery); :I_p4S.)
} r$[`A_
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publicList findByNamedQuery(finalString query, ,w`g+ 9v
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finalObject parameter){ $7h]A$$Fv
return getHibernateTemplate 4Vtug>
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().findByNamedQuery(query, parameter); Q$+6f,m#W
} u7&q(Z&&O
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publicList findByNamedQuery(finalString query, RW~!)^
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finalObject[] parameters){ q QcQnd2K
return getHibernateTemplate mR["xDHD
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().findByNamedQuery(query, parameters); w*?SGW
} %xt;&HE
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publicList find(finalString query){ +3uPHpMB-
return getHibernateTemplate().find T@wgWE<0y_
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(query); 'oKen!?A
} u9nJ;:
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publicList find(finalString query, finalObject . ;rE4B
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parameter){ 9xi nX-x;n
return getHibernateTemplate().find 5P Zzaz<
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(query, parameter); K;z$~;F
} _(zZrUHB
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public PaginationSupport findPageByCriteria *+OS;R1<
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(final DetachedCriteria detachedCriteria){ ?(Se$iTZ
return findPageByCriteria OZc4 -5
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); J>l?HK
} |v:oLgUdH
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public PaginationSupport findPageByCriteria H*j!_>W
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(final DetachedCriteria detachedCriteria, finalint 1rx,qfCq
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startIndex){ xi51,y+(5
return findPageByCriteria y'aK92pF:
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(detachedCriteria, PaginationSupport.PAGESIZE, WNY:HH
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startIndex); NSa6\.W)
} zO`4W!x&
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public PaginationSupport findPageByCriteria [#=IKsO'R6
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(final DetachedCriteria detachedCriteria, finalint l`uI K.
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pageSize, 7nm'v'\u+V
finalint startIndex){ ,,SV@y;
return(PaginationSupport) )I#{\^
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getHibernateTemplate().execute(new HibernateCallback(){ Fw\g\
publicObject doInHibernate \TZSn1isZX
e)= "Fq!
(Session session)throws HibernateException { ZNVrja*
Criteria criteria = Sn
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detachedCriteria.getExecutableCriteria(session); z&cM8w:
int totalCount = 7Db}bDU1
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((Integer) criteria.setProjection(Projections.rowCount T|8:_4/l
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()).uniqueResult()).intValue(); "OwK-
criteria.setProjection ]5K+W
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(null); cZJ5L>ox
List items = LSo*JO6
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criteria.setFirstResult(startIndex).setMaxResults g<@Q)p*ow
),CKuq>
(pageSize).list(); ? cXW\A(
PaginationSupport ps = /IN#1I!K
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new PaginationSupport(items, totalCount, pageSize, HKr}"`I.
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startIndex); RC}m]!Uz
return ps; w3ATsIw
} _p>F43%p
}, true); ,-hbwd~M
} n$`+03 a
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public List findAllByCriteria(final ufCpX>lNF
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DetachedCriteria detachedCriteria){ _1Q6FI5iR
return(List) getHibernateTemplate IMr#5
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().execute(new HibernateCallback(){ ?2l`%l5(
publicObject doInHibernate + %v1X&_\
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(Session session)throws HibernateException { O/|))H?C
Criteria criteria = U(0FL6sPC
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detachedCriteria.getExecutableCriteria(session); K-~g IlbQ`
return criteria.list(); JO*/UC>"
} BPa,P_6(
}, true); Fsm6gE`|n
} Q^ZM| (s#
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public int getCountByCriteria(final Q5ff&CE
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DetachedCriteria detachedCriteria){ T>]T=
Integer count = (Integer) s;YbZ*oaMe
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getHibernateTemplate().execute(new HibernateCallback(){ od{\z
publicObject doInHibernate 4d%0a%Z
q\}+]|nGs
(Session session)throws HibernateException { ,cL;,YN
Criteria criteria = 5@%.wb4
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detachedCriteria.getExecutableCriteria(session); {aN pk,n
return R|}N"J _
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criteria.setProjection(Projections.rowCount F$(ak;v}
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()).uniqueResult(); g9q}D-
} O>pv/Ns
}, true); ^ZO! (
return count.intValue(); Nf^<pT[*
} %s"&|32
} C+uW]]~I)
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用户在web层构造查询条件detachedCriteria,和可选的 ,5"(m?[m
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 GyWa=KW.u
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PaginationSupport的实例ps。 3ZI7;Gw
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ps.getItems()得到已分页好的结果集 C6[W/,eS
ps.getIndexes()得到分页索引的数组 %2T
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ps.getTotalCount()得到总结果数 h#"$W;(
ps.getStartIndex()当前分页索引 G/N c@XG\
ps.getNextIndex()下一页索引 r":anR( ;
ps.getPreviousIndex()上一页索引 ?9a%g\`?:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R__:~uv,
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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 UPU$SZAIx
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一下代码重构了。 uD>=
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我把原本我的做法也提供出来供大家讨论吧: ?:J_+?{E
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首先,为了实现分页查询,我封装了一个Page类: WA8<:#{e
java代码: o]4\Geg$
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/*Created on 2005-4-14*/ >Ua'*
package org.flyware.util.page; T:$^1"\
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/** iyl
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* @author Joa ^;RK-)
* RyJy%|\-S
*/ ]a4U\yr
publicclass Page { Sp80xV_B
Bi:lC5d5?
/** imply if the page has previous page */ kun/KY
privateboolean hasPrePage; \;)g<TwL
Kd`(^
/** imply if the page has next page */ e4tIO
privateboolean hasNextPage; ?`piie9V
<bKtAf
/** the number of every page */ 985F(r
privateint everyPage; _-TplGSO=c
jr4xh{Z`
/** the total page number */ IC0L&;En
privateint totalPage; Io]FDPN
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/** the number of current page */ TVD~Ix
privateint currentPage; U =.PL\
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/** the begin index of the records by the current eBrNhE-[G]
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query */ ,Z@#( =f
privateint beginIndex; X_TjJmc
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/** The default constructor */ ?bB>}:~j)
public Page(){ W`;;fJe
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} lGd'_~'=
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/** construct the page by everyPage =Z^5'h~
* @param everyPage ~=|}!A(
* */ *,\"}x*
public Page(int everyPage){
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this.everyPage = everyPage; q-JTGCFl
} VsQ|t/|#
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/** The whole constructor */ X.fVbePxUU
public Page(boolean hasPrePage, boolean hasNextPage, TEC^|U`G
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int everyPage, int totalPage, +Q5O$8i
int currentPage, int beginIndex){ ED&nrd1P
this.hasPrePage = hasPrePage; d &#_t@%
this.hasNextPage = hasNextPage; D\Ak-$kJ^
this.everyPage = everyPage; cc[(w
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this.totalPage = totalPage; b>07t!;
this.currentPage = currentPage; u"v7shRp:
this.beginIndex = beginIndex; O?e9wI=H
} 2)f_L|o,m
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/** *7!MG
* @return TA[%eMvA
* Returns the beginIndex. LZykc
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*/ OIblBQ!
publicint getBeginIndex(){ B.8B1MFm
return beginIndex; <]rayUyaf
} -b-a21,m>
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/** kKyU?/aj
* @param beginIndex gu
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* The beginIndex to set. 5|H;%T3_
*/ ,!:c6F+
publicvoid setBeginIndex(int beginIndex){ \*$^}8
this.beginIndex = beginIndex; i KSRr#/
} ea3w
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/** ReaZg ?:h
* @return z=D5*
* Returns the currentPage. 6FB0g8
*/ 7hk)I`o65
publicint getCurrentPage(){ |bnd92fvks
return currentPage; ]v
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} A({czHLhN5
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/** 'Ea3(OsuXn
* @param currentPage fCY|iO0.t
* The currentPage to set. #w{`6}p
*/ tia}&9;
publicvoid setCurrentPage(int currentPage){ J}V4.R5d
this.currentPage = currentPage; 9)!Ksg(h
} FQWjL>NB
V;SfW2`)
/** P27Ot1px
* @return 3qWrSziD
* Returns the everyPage. (qAF2&
*/ FWW4n_74
publicint getEveryPage(){ :|j[{;asY
return everyPage; s\ *p|vc
} nDrRK
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/** 0}i
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* @param everyPage / 4Q=%n
* The everyPage to set. ^A ]4
*/ O@$>'Z
publicvoid setEveryPage(int everyPage){ i;HXz`vT7
this.everyPage = everyPage; LW=qX%o{
} nDkG}JkB!
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/** Rxy|Ag/I;V
* @return rVabkwYD
* Returns the hasNextPage. +C=vuR
*/ .\bJ,of9
publicboolean getHasNextPage(){ Dk\%,[4(
return hasNextPage; {tVA(&\<
} H;=yR]E
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/** t_/qd9Jv
* @param hasNextPage wo9R:kQ
* The hasNextPage to set. !KV!Tkx h
*/ zZ}.2He8
publicvoid setHasNextPage(boolean hasNextPage){ )F9IzR-&m
this.hasNextPage = hasNextPage; .3EEi3z6z
}
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/** 5]{rim
* @return !jP[=
* Returns the hasPrePage. /8Lb_QH{
*/ xEG:KSH
publicboolean getHasPrePage(){ py$Gy-I~[
return hasPrePage; GUQ3XF\
} ]`-o\,lq
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/** A7QT4h&6
* @param hasPrePage F]OWqUV
* The hasPrePage to set. `@Z$+
*/ }r04*P(
publicvoid setHasPrePage(boolean hasPrePage){ mcwd2)
this.hasPrePage = hasPrePage; qRT5|\l
} Fmn_fW6
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/** ,,FhE
* @return Returns the totalPage. o5],c9R9b
* n(A;:)W{
*/ +46& Zb35
publicint getTotalPage(){ i% 0qN
return totalPage; Ps!
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} P w6l'
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/** ,ig`'U
* @param totalPage Lh+7z>1
* The totalPage to set. )~)T[S
*/ kb-XEJ}L
publicvoid setTotalPage(int totalPage){ ; 180ct4
this.totalPage = totalPage; =>*}qen
} aV fsF|,
9Eh*r@>
} r 8N<<^
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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 ^g'uR@uU
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个PageUtil,负责对Page对象进行构造: w&U28"i>
java代码: :hHKm|1FE
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/*Created on 2005-4-14*/ {s@&3i?ZiC
package org.flyware.util.page; 1\jj3Y'i'
I/h( *~/
import org.apache.commons.logging.Log; JWt@vf~
import org.apache.commons.logging.LogFactory; #,jm3Mqj
3&X5*-U
/** 'fb&3
* @author Joa <Rt0
V%}-
* ziAn9/sT
*/ P@etT8| V
publicclass PageUtil { V2Z^W^
d.sn D)X
privatestaticfinal Log logger = LogFactory.getLog a/d8_(0
nQw, /Lk
(PageUtil.class); ylmVmHmc
AWZ4h,as{
/** 4YMUkwh
* Use the origin page to create a new page R<T5lkJ\/
* @param page rp-.\Hl/a
* @param totalRecords 3qfQlqJ&3
* @return ?AQR\) P
*/ C-2#-{<
publicstatic Page createPage(Page page, int eET1f8B=L
5IG#-Q(6sp
totalRecords){ : 2L-Nf
return createPage(page.getEveryPage(), 7r3EMX\#Qm
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page.getCurrentPage(), totalRecords); "jq F
} }g.)%Bw!
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/** cMUmJH
* the basic page utils not including exception P; =,Q$e8
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handler pr"q-S>E
* @param everyPage w="
* @param currentPage $+
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* @param totalRecords ;;17 #T2
* @return page %Y].i/".;P
*/ h*NBSvn
publicstatic Page createPage(int everyPage, int X{5(i3?S
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currentPage, int totalRecords){ BfvvJh_
everyPage = getEveryPage(everyPage); p6{8t}
currentPage = getCurrentPage(currentPage); jivGkIj!8
int beginIndex = getBeginIndex(everyPage, O~bzTn
v3/G.B@=
currentPage); H+5N+AKb@
int totalPage = getTotalPage(everyPage, ~EhM"go
"CQ:<$|$
totalRecords); 3}?]G8iL?L
boolean hasNextPage = hasNextPage(currentPage, ue6&)7:~
*Q3q(rdrp
totalPage); ^paM{'J\\)
boolean hasPrePage = hasPrePage(currentPage); tw]Q5:6
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returnnew Page(hasPrePage, hasNextPage, c(S66lp
everyPage, totalPage, >x1?t
currentPage, i\P)P!
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beginIndex); pL'+sW
} OEgp!J
"\Nn,3qp
privatestaticint getEveryPage(int everyPage){ G
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return everyPage == 0 ? 10 : everyPage; NHzhGg]
} jTz~
V&^
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privatestaticint getCurrentPage(int currentPage){ &p^8zE s
return currentPage == 0 ? 1 : currentPage; .\ces2,
} @X>Oj .
jUX0sRDk
privatestaticint getBeginIndex(int everyPage, int $~.'Tnk)
>BlF<
d`X
currentPage){ n|I5ylt
return(currentPage - 1) * everyPage; }7|UA%xz
}
lxD~[e
LZ*ZXFIg
privatestaticint getTotalPage(int everyPage, int 64-;| k4F
p# (5
;
totalRecords){ q vGkTE
int totalPage = 0; B"I^hrQ
QPpC_pZh
if(totalRecords % everyPage == 0) `GT{=XJfY
totalPage = totalRecords / everyPage; 4Q(GX.5
else kC-OZ VoO
totalPage = totalRecords / everyPage + 1 ; >a2i%j/T
Sy`7 })[
return totalPage; CrI:TB>/"
} },G5!3
LYyOcb[x
privatestaticboolean hasPrePage(int currentPage){ 'e06QMp@
return currentPage == 1 ? false : true; 7^Q4?(A
} c'~6 1HA<
UB1/0o
privatestaticboolean hasNextPage(int currentPage, :HQQ8uQfb
x.~A vJ
int totalPage){ }0~4Z)?e3
return currentPage == totalPage || totalPage == x\R
8W8M
m'.y,@^B
0 ? false : true; rOd~sa-H
} CQm(N
wLz@u$u?
&C=[D_h
} Z]1jg>")
u'+;/8
6#/v:;bF
f+Ht
E;AOCbV*$
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。 JQ)w/@Vu=
;4ETqi9
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 m<uBRI*I
bs=x>F
做法如下: v46 5Z
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 [GqQ6\
iSg^np
的信息,和一个结果集List: ^9*kZV<K
java代码: V1Opp8
)Cfk/OnRd
||t"}Y
/*Created on 2005-6-13*/ Zw<\^1
package com.adt.bo; 05gdVa,
1iTI8h&[@
import java.util.List; {
vOr'j@
SV0h'd(b
import org.flyware.util.page.Page; B78e*nNS#2
_)?59
/** n6]8W^g
* @author Joa MYVgi{
*/ )tW0iFY
publicclass Result { /I/gbmc)
I c 2R\}q
private Page page; Z0I>PBL@l
;Wu6f"+Y#
private List content; )UgLs|G~
~SN *
/** 85GU~.
* The default constructor C=>IJ'G
*/ [uD G;We=
public Result(){ I@/+=
super(); yhSbX4Q
} +<o}@hefY2
>q7/zl
/** mxfmK +'_
* The constructor using fields FLzC kzJ:6
* qPG>0
O
* @param page kMP3PS
* @param content u?B9zt%$-m
*/ /l&$B
public Result(Page page, List content){ nA?Ks!9T
this.page = page; EYD24
this.content = content; r(VznKSx
} >j$y@"+
"|KhqV=?v
/** (AI
4a+
* @return Returns the content. ;*}tbh3;.
*/ |s$w
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publicList getContent(){ P/XCaj3a[
return content; 'V#$PZx
} zo>@"uH4
%ot4$eY
/** N0_@=uE
* @return Returns the page. #l?E2
U4WL
*/ f\U(7)2
public Page getPage(){ }@H(z
return page; "F+m}GJ=a
} Q^!x8oUF
[;RO=
/** {GP#/5$=
* @param content Qf#=Y j
* The content to set. '`nf7b(
*/ VY|'7in"M
public void setContent(List content){ cWS 0B $$
this.content = content; `+0K~k|DC
} EYXHxo
Yw_^]:~
/** mo()l8
* @param page /fDXO;tN
* The page to set. aF]cEe
*/ ews{0
publicvoid setPage(Page page){ A$o7<Hx
this.page = page; 0wnC"2GUX
} 7Z[6_WD3
} h51)kN:
i_<GSUTTr/
vg;9"A!(
jH~VjE>
IJ E{JH
2. 编写业务逻辑接口,并实现它(UserManager, yYN _]&ag
_k O<|ev
UserManagerImpl) \;bDDTM
java代码: 8qF OO3c\V
@h)Z8so
Nm4
h
/*Created on 2005-7-15*/ NPjNkpWm&=
package com.adt.service; }$X/HK
&X&msEM
import net.sf.hibernate.HibernateException;
;U<}2M!g
cl1>S 3
import org.flyware.util.page.Page; Or<OmxJg
oj%(@6L
import com.adt.bo.Result; (F=q/lK$
*pj^d><
/** (JdZl2A.
* @author Joa - xKa-3
*/ =GJ)4os
publicinterface UserManager { =s/UF _JN
we}G%09L
public Result listUser(Page page)throws N SkIzaNY
uG,*m'x']
HibernateException; |kK_B
:K
26B+qXEt
} 94Q?)0W$
*w5xC5*
tLSM]Q
:TkR]bhm
y^[?F>wB
java代码: :[d*
GMOnp$@H^s
=" ;G&)H-
/*Created on 2005-7-15*/ 2`P=ekF]
package com.adt.service.impl; `PS^o#
v4Mn@e_#c
import java.util.List; aaRc?b'/
uRCZGg&V?#
import net.sf.hibernate.HibernateException; 4#Cm5xAt6
4"~F
import org.flyware.util.page.Page; Zg=jDPt}
import org.flyware.util.page.PageUtil; HIsB)W&%@
dh K<5E
import com.adt.bo.Result; d<_#Q7]I4
import com.adt.dao.UserDAO; LVe[N-K
import com.adt.exception.ObjectNotFoundException; JxmFUheLt
import com.adt.service.UserManager; ocPM zq-
\#7@"~<
/** J-5E# v
* @author Joa eJ+@<+vr;x
*/ QA=mD^A
publicclass UserManagerImpl implements UserManager { GD@|XwK){
RGe2N|
private UserDAO userDAO; ,%d?gi"&
R4g;-Ci->
/** d:3OC&
* @param userDAO The userDAO to set. t
.-%@,s
*/ R
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publicvoid setUserDAO(UserDAO userDAO){ ,-`A6ehg
this.userDAO = userDAO; ^^(!>n6r^
} d*R('0z{
@XQItc<
/* (non-Javadoc) L['g')g.
* @see com.adt.service.UserManager#listUser * _@t$W
Ex-?[Hq
(org.flyware.util.page.Page) 1+v!)Y>Z&
*/ H$rNT/C
public Result listUser(Page page)throws lN~u='Kc
z$Z{ LR
HibernateException, ObjectNotFoundException { \'.|7{Xu
int totalRecords = userDAO.getUserCount(); ;!pSYcT,
if(totalRecords == 0) 4_W*LG~2s
throw new ObjectNotFoundException TrR=3_;.7
cm17hPe`}n
("userNotExist"); e N^6gub
page = PageUtil.createPage(page, totalRecords); K9QC$b9(
List users = userDAO.getUserByPage(page); WPDi)UX
returnnew Result(page, users); +j(7.6ia
} ('1]f?:M
"'*Qq@!3?
} W0k7(v)
m8<.TCIQ
%`\=qSf*
Wa<SYJ
Lk2;\ D>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "U|u-ka8B
:wY(</H
询,接下来编写UserDAO的代码: v{;^>"5o
3. UserDAO 和 UserDAOImpl: Nin7AOO
java代码: 89P'WFOFK
kzmw1*J
,b9!\OWDF
/*Created on 2005-7-15*/ EI8KK o *
package com.adt.dao; :=?od
0]W
9s&dN
import java.util.List; MeDlsO
CPci
'SO
import org.flyware.util.page.Page; g_;4@jwTP"
:vJ1Fo!
import net.sf.hibernate.HibernateException; FJ] ?45
,pIaYU{D
/** u[6aSqwC|
* @author Joa *?YMoN
*/ 1eOQ;#OV
publicinterface UserDAO extends BaseDAO { )-^[;:B\k"
W%@0Y m`7
publicList getUserByName(String name)throws )St`}qu;
Ma^}7D
/
HibernateException; 5%]O'h
+wGFJLHJ
publicint getUserCount()throws HibernateException; 0aa&13!5
\{.c0
publicList getUserByPage(Page page)throws Vc!'=&*
wxE'h~+
HibernateException; NX8.
\Pf#
>D_!d@Z
} Q(jIqY1Hf
:aR_f`KMm
k-I U}|Xz
\[<8AV"E-'
n'83P%x
java代码: `{H!V~42
Ntlbn&lc;D
i|!W;2KL5
/*Created on 2005-7-15*/ qlC4&82=Q
package com.adt.dao.impl; .o)
Sz-TarTF
import java.util.List; D-Q54 "^3
q.ZkQN+
import org.flyware.util.page.Page; G2w0r,[
-u~AY#*
import net.sf.hibernate.HibernateException; n!h952"
import net.sf.hibernate.Query; d,E2l~s
#D^(dz*
import com.adt.dao.UserDAO; VJS1{n=;k
"0m\y+%8
/** $GQ{Ai:VwF
* @author Joa />O.U?
*/ i QvqifDmh
public class UserDAOImpl extends BaseDAOHibernateImpl M3s:B& /
AQD`cG
implements UserDAO { +pxtar
x.>&|Ej
/* (non-Javadoc) UV\&9>@L
* @see com.adt.dao.UserDAO#getUserByName HXgf=R/$
z6Zd/mt~x
(java.lang.String) P\&n0C~
*/ >:|jds#
publicList getUserByName(String name)throws 7~H"m/;U&
a0PClbf2.
HibernateException { 8gW$\
String querySentence = "FROM user in class JfzfxfM
$KPf[JvQ
com.adt.po.User WHERE user.name=:name"; +r$VrNVs
Query query = getSession().createQuery /2Bf6
[Q[ac 6f
(querySentence); rTzXRMv@o
query.setParameter("name", name); QeQxz1
return query.list(); z'}z4^35,
} @+hO,WXN
b&!x.+d-z
/* (non-Javadoc) 9>ML;$T&
* @see com.adt.dao.UserDAO#getUserCount() P.3kcZ
*/ P(B&*1X
publicint getUserCount()throws HibernateException { EO\- J-nM
int count = 0; & sgzSX
String querySentence = "SELECT count(*) FROM
QJ,~K&?
lh-zE5;
user in class com.adt.po.User"; smPZ%P}P+c
Query query = getSession().createQuery h%&2M58:
oiItQ4{<
(querySentence); PDb7 h
count = ((Integer)query.iterate().next u(~( +1W
!BR@"%hx
()).intValue(); &"=<w
return count; &?^"m\K4J*
} M<ba+Qn$
?GGBDql
/* (non-Javadoc) .=@CF8ArG
* @see com.adt.dao.UserDAO#getUserByPage &G_XgQsg{
e|4U2\&3y
(org.flyware.util.page.Page) i}~U/.P
*/ \N.Bx
publicList getUserByPage(Page page)throws 'h>CgR^NM1
41c4Xj?'
HibernateException { cD9.L
String querySentence = "FROM user in class K%YR; )5A
C:RA(
com.adt.po.User"; \iAs
Query query = getSession().createQuery C,,S<=L:
B1va]=([)W
(querySentence); 07>Iq8<mu
query.setFirstResult(page.getBeginIndex()) H'jo3d~+
.setMaxResults(page.getEveryPage()); F+9(*|x%
return query.list(); i*e'eZ;)
} a>#]d
_^p\
u
} "T.Qb/97@
@UW*o&pGqL
4d%QJ7y
@|fT%Rwho<
!DXK\,;>
至此,一个完整的分页程序完成。前台的只需要调用 -~]]%VJP|
):nC&M\W~
userManager.listUser(page)即可得到一个Page对象和结果集对象 k.wm{d]J
Ki\J)l
的综合体,而传入的参数page对象则可以由前台传入,如果用 p*~b5'+ C+
N2&h yM
webwork,甚至可以直接在配置文件中指定。 aA-s{af
LuWY}ste
下面给出一个webwork调用示例: t{O2JF#5u
java代码: J"Nn.iVq
#4F0o@Z
]EEac
/*Created on 2005-6-17*/ &J,&>CFc
package com.adt.action.user; 8YO` TgW
+[Q`I*C
import java.util.List; ML7qrc;Rx
d8VFa'|
import org.apache.commons.logging.Log; b\C1qM4
import org.apache.commons.logging.LogFactory; 4GexYDk'#
import org.flyware.util.page.Page; `Lr|KuFN
@O
HsM?nW
import com.adt.bo.Result; Gy!bPVe
import com.adt.service.UserService; Im@Yx^gc
import com.opensymphony.xwork.Action; W@61rT}c
OGPrjL+
/** 0[1/#0$
* @author Joa A3Y}|7QA
*/ 8\m[Nuq5
publicclass ListUser implementsAction{ BHDd^bd
=]P|!$!}0
privatestaticfinal Log logger = LogFactory.getLog qKNHhXi
S=3 H.D!f
(ListUser.class); ,m;G:3}48
E*83N@i
private UserService userService; m>+e;5
/}=cv>S5V
private Page page; EkEQFd 5g
>7 qZ\#
privateList users; p&ZLd`[
S=X_7V
/* yOyuMZo6
* (non-Javadoc) Y|aaZ|+
* |],ocAN{
* @see com.opensymphony.xwork.Action#execute() jiP^Hz"e
*/ J pKCux
publicString execute()throwsException{ L[lS
>4eN
Result result = userService.listUser(page); ?]0bR]}y
page = result.getPage(); B2,JfKk/
users = result.getContent(); b#:!b
return SUCCESS; /y-8dgv0a
} / a$B8,
qoOq47F
/** d2*uY.,
* @return Returns the page. _tfi6UQ&lY
*/ 8v\^,'@
public Page getPage(){ /qweozW_+
return page; |4F'Zu}g>
} ,zh4oX`>
3|0OW
Jk
/** }Pj;9ivz
* @return Returns the users. <Y ^)/ s
*/ o<7'(Pz
publicList getUsers(){ idNg&'
return users; Ui}%T]
} R9InUX"k
hvF>Tu]^r
/** dA$qzQ
* @param page K"VRHIhfg
* The page to set. |%fM*F^7/
*/ 6='x}Qb \H
publicvoid setPage(Page page){ #)( D_*
this.page = page; pxHJX2
} iTJE:[W"y
{Zf 9}
!qF
/** _yc&'Wq
* @param users ?9;r|G
* The users to set. A(wuRXnVWK
*/ !k8j8v&
publicvoid setUsers(List users){ M[?0 ^ FBx
this.users = users; "sUmk e-#
} y\<