Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 =
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 AH`D&V
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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 bep}|8,#u
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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 G?12?2
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分页支持类: c/
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java代码: LB%_FT5
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package com.javaeye.common.util; , M$*c
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import java.util.List; xG0IA 7
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publicclass PaginationSupport { \lHi=}0
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publicfinalstaticint PAGESIZE = 30; WpC@nz?
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privateint pageSize = PAGESIZE; 0X+Jj/-ge
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privateList items; k\_>/)g
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privateint totalCount; b,5H|$nLu
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privateint[] indexes = newint[0]; wE3^6
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privateint startIndex = 0; o*97Nbjn
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public PaginationSupport(List items, int mU:C{<Z
//KTEAYyy#
totalCount){ 0:Js{$ZL4
setPageSize(PAGESIZE); mn\e(WoX
setTotalCount(totalCount); wRf_IBhCd
setItems(items); k#`.!yI,
setStartIndex(0); 3O%[k<S\VO
} lT$Vv=M
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public PaginationSupport(List items, int srx`"
:
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totalCount, int startIndex){ +^<CJNDL9
setPageSize(PAGESIZE); iKV;>gF,)v
setTotalCount(totalCount); <VB
setItems(items); eB/3MUz1
setStartIndex(startIndex); N::_JH?^=
} h3aHCr E
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public PaginationSupport(List items, int ?nrd$,
* kgbcU f8
totalCount, int pageSize, int startIndex){ v"O{5LM"
setPageSize(pageSize); Rg<y8~|'}
setTotalCount(totalCount); zF<*h~
setItems(items); LYGFEjS[
setStartIndex(startIndex); {#uX
} r$;DA<<|<c
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publicList getItems(){ :::"C"Ge
return items; z1f~:AdL
} )8ctNpQt
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publicvoid setItems(List items){ (Z)
this.items = items; P^v`5v
} =w".B[r
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publicint getPageSize(){ zdyS"H}
return pageSize; "<3PyW?zt
} dSsMa3X[n
!-x^b.${B
publicvoid setPageSize(int pageSize){ $b\Gl=YX^
this.pageSize = pageSize; :Ff1Js(Z
} X)fj&
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publicint getTotalCount(){ e.\d7_T+
return totalCount; vrGRZa
} [@#P3g\:>W
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publicvoid setTotalCount(int totalCount){ oQ8W0`bZa
if(totalCount > 0){ S`K8e^]
this.totalCount = totalCount; [>;U1Wt
int count = totalCount / $>OWGueq64
t=iy40_T
pageSize; DDN#w<#
if(totalCount % pageSize > 0) %l,p />r
count++; _R]la&^2F\
indexes = newint[count]; ?5'UrqYSW
for(int i = 0; i < count; i++){ cQu1WgQ
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indexes = pageSize * Z)|*mJ
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i; e}(ws~.
} rh${pHl
}else{ |6"zIHvtc
this.totalCount = 0;
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} wR@fB
} n_)d4d zl
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publicint[] getIndexes(){ i~n>dc YW
return indexes; <{9E.6G`n
} NL0X =i
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publicvoid setIndexes(int[] indexes){ :I+%v
this.indexes = indexes; 9@Cqg5Kx'
} +<Uc42i7n
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publicint getStartIndex(){ r_-iOxt~5
return startIndex; U" aFi
} C*/d%eHD
4 rw<C07Z
publicvoid setStartIndex(int startIndex){ p(v+j_ak
if(totalCount <= 0) )`,3/i9C$
this.startIndex = 0; ljlQ9wb[s
elseif(startIndex >= totalCount) Jf|J":S
this.startIndex = indexes `V$i*{c:#
+smPR
[indexes.length - 1]; pI( OI>~3
elseif(startIndex < 0) Xi6XV3G
this.startIndex = 0; 2J|Wbey
else{ &`Z>z T}
this.startIndex = indexes =eDVgOZ)
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[startIndex / pageSize]; n*9)Y~
} <FRYt-+
} <I&X[Sqp
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publicint getNextIndex(){ aHXd1\6m
int nextIndex = getStartIndex() + {}s7q|$
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pageSize; /Pxt f~$
if(nextIndex >= totalCount) 6*lTur9ni
return getStartIndex(); nkG1&wiX
else Elom_
return nextIndex; q#xoM1
} BB.^-0up
Y#=0C*FS
publicint getPreviousIndex(){ O8wR#(/
int previousIndex = getStartIndex() - N41)?-7F
] L"jt8E
pageSize; N8@Fj!Zi
if(previousIndex < 0) X"z^4?Aj+
return0; T[`o$j6
else 0B>hVaj>-
return previousIndex; r,cV(
} eBFsKOtu
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} u3a"[DB9c
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抽象业务类 ,,sKPj[
java代码: >=G;rs
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/** *P7 H=Yf&
* Created on 2005-7-12 )\s{\u
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*/ vO`~rUA
package com.javaeye.common.business; i%_W{;e
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import java.io.Serializable; E#[_"^n
import java.util.List; !nQ_<
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import org.hibernate.Criteria; Ngi]I#Vz
import org.hibernate.HibernateException; `|)V]<
import org.hibernate.Session; [3lAKI
import org.hibernate.criterion.DetachedCriteria; Sg
import org.hibernate.criterion.Projections; S~()A*5
import #Z#rOh
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org.springframework.orm.hibernate3.HibernateCallback; |L[/]@|
import
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org.springframework.orm.hibernate3.support.HibernateDaoS 6|:K1bI)
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upport; UR?biq
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import com.javaeye.common.util.PaginationSupport; iga.B
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public abstract class AbstractManager extends uE] HU
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HibernateDaoSupport { "`g5iUHqUl
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privateboolean cacheQueries = false; AK$&'t+$}7
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privateString queryCacheRegion; *Tc lcu
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publicvoid setCacheQueries(boolean =D;n#n 7
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cacheQueries){ Gk:tT1
this.cacheQueries = cacheQueries; rf?%- X(V
} AS4mJ UU9
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publicvoid setQueryCacheRegion(String DpQ\q;
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queryCacheRegion){ @*e5(@R
this.queryCacheRegion = HpP82X xj
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queryCacheRegion; FQTAkkA_!
} Ls<^z@I
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publicvoid save(finalObject entity){ )iX2r{
getHibernateTemplate().save(entity); Ef @
} 9]C%2!Ur,
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publicvoid persist(finalObject entity){ 9*Q6/?v
getHibernateTemplate().save(entity); *Xcqnu('
} hKnAWKb0
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publicvoid update(finalObject entity){ 3 C{A
getHibernateTemplate().update(entity); :a/l9 m(
} Gr-~&pm
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publicvoid delete(finalObject entity){ 7F2 WmMS
getHibernateTemplate().delete(entity); +Jm~Um!
} 3iM7c.f*/
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publicObject load(finalClass entity, .^dtdFZ8,
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finalSerializable id){ A^ofs*"Y
return getHibernateTemplate().load z~"Q_gme
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(entity, id); ?lE&ow
} a8$4
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publicObject get(finalClass entity, A(_HMqA]
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finalSerializable id){ 3n,jrX75u
return getHibernateTemplate().get 8eVy*h2:=
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(entity, id); nll=Vd[
} EXMW,
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publicList findAll(finalClass entity){ a,36FF~&
return getHibernateTemplate().find("from i#98KzE
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" + entity.getName()); 4a0Ud !Qcs
} qt(4?_J
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publicList findByNamedQuery(finalString 6f2?)jOW^N
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namedQuery){ cLEd-{x
return getHibernateTemplate mqHcD8X
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().findByNamedQuery(namedQuery); 3-btaG'P
} _aYhW{wW
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publicList findByNamedQuery(finalString query,
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finalObject parameter){ X::@2{-@y
return getHibernateTemplate Siq]Ii0F;>
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().findByNamedQuery(query, parameter); udT0`6l;
} EnGh&]
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publicList findByNamedQuery(finalString query, @<3E`j'p
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finalObject[] parameters){ %%F,G
return getHibernateTemplate qdLzB
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().findByNamedQuery(query, parameters); >yr;Y4y7K
} !uit
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publicList find(finalString query){ !KJA)znx;(
return getHibernateTemplate().find $@@ii+W}\
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(query); 0r_~LN^|[
} #q K.AZi
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publicList find(finalString query, finalObject pj<aMh
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parameter){ W**[:n+
return getHibernateTemplate().find L*dGo,oN
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(query, parameter); Z'`\N@c#
} Zo-,TKgY'
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public PaginationSupport findPageByCriteria 4lR+nmAZ
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(final DetachedCriteria detachedCriteria){ h<)ceD<,
return findPageByCriteria >?OUs>}3y2
.?rs5[th*
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Uj\t04
} P5h*RV>oS
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public PaginationSupport findPageByCriteria +,,dsL
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(final DetachedCriteria detachedCriteria, finalint "=n%L +6%
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startIndex){ tK[o"?2y
return findPageByCriteria W!T[
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(detachedCriteria, PaginationSupport.PAGESIZE, BJ]L@L%
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startIndex); |=v,^uo
} m'
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public PaginationSupport findPageByCriteria 3 ^x&G?)
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(final DetachedCriteria detachedCriteria, finalint U\ ,N
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pageSize, AcEz$wy
finalint startIndex){ kCEo */,
return(PaginationSupport) E+EcXf
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getHibernateTemplate().execute(new HibernateCallback(){ !( +M
publicObject doInHibernate ZvQZD=,F
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(Session session)throws HibernateException { #g@4c3um|
Criteria criteria = L4T\mP7D7*
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detachedCriteria.getExecutableCriteria(session); fQ"Vx!
int totalCount = IY6Qd4157
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((Integer) criteria.setProjection(Projections.rowCount %-fS:~$
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()).uniqueResult()).intValue(); *2N0r2t&
criteria.setProjection BMQ4i&kF|
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(null); tS\Db'C7
List items = qhG2j;
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criteria.setFirstResult(startIndex).setMaxResults yMM2us#*+q
9@lG{9id?
(pageSize).list(); Ake l .&
PaginationSupport ps = G9xO>Xp^Al
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new PaginationSupport(items, totalCount, pageSize, <\uDtbK
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startIndex); [>_zV.X
return ps; 7LM&3mA<
} [-"ZuUG
}, true); gaNe\
} {|OXiRm'
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public List findAllByCriteria(final Wi5Dl=
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DetachedCriteria detachedCriteria){ 'byTM?Sp{
return(List) getHibernateTemplate %dr*dA'
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().execute(new HibernateCallback(){ ts_|7Ev
publicObject doInHibernate @c"s6h&
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(Session session)throws HibernateException { P_mP ^L
Criteria criteria = \kY:|T
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detachedCriteria.getExecutableCriteria(session); ]Lg~I#/#
return criteria.list(); i4WHjeo\
} B<Cg_C
}, true); 2*cc26o
} qe?Ns+j<d
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public int getCountByCriteria(final %qE"A6j
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DetachedCriteria detachedCriteria){ {[/A?AV;F
Integer count = (Integer) "|Y y"iB[
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getHibernateTemplate().execute(new HibernateCallback(){ 8yDsl
publicObject doInHibernate #h9Gl@|
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(Session session)throws HibernateException { 9&Y|,&W
Criteria criteria = eTw9c }[
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detachedCriteria.getExecutableCriteria(session); BG.8 q4[
return CK|AXz+EN
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criteria.setProjection(Projections.rowCount YSfJUB!I
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()).uniqueResult(); x;} 25A|
} :J x%K
}, true); j` * bz-
return count.intValue(); MF*4E9Ue.
} (]&B'1b
} T$<'ZC
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用户在web层构造查询条件detachedCriteria,和可选的 y@2"[fo3~
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 :M`~9MCRf
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PaginationSupport的实例ps。 aM#xy6:XG
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ps.getItems()得到已分页好的结果集 eOXu^M>:F
ps.getIndexes()得到分页索引的数组 55] MRv
ps.getTotalCount()得到总结果数 e.XD5~Ax
ps.getStartIndex()当前分页索引 C8)s6
ps.getNextIndex()下一页索引 MU `!sb*
ps.getPreviousIndex()上一页索引 ER[$TH&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 s,/C^E
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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 87)/dHc
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一下代码重构了。 Hl{ul'o
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我把原本我的做法也提供出来供大家讨论吧: Qn-nO_JL
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首先,为了实现分页查询,我封装了一个Page类: $DnJ/hg;qD
java代码: asy:[r"
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/*Created on 2005-4-14*/ w6lx&K-
package org.flyware.util.page; ajM\\a?
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/** f= }!c*l"
* @author Joa gd7!+6
* b%C7 kL-
*/ rF{,]U9`
publicclass Page { 5s4x%L (~}
30s A\TZ
/** imply if the page has previous page */ z`u$C+Ov
privateboolean hasPrePage; Gtvbm
c3<H272\
/** imply if the page has next page */ o{hZjn-
privateboolean hasNextPage; 5dX0C
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/** the number of every page */ h*Mi/\
privateint everyPage; rCA0c8
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/** the total page number */ *kj+6`:CPs
privateint totalPage; ?01ru5ys/o
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=_
/** the number of current page */ rV-Xsf7Z
privateint currentPage; 4Y
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/** the begin index of the records by the current ,Vz-w;oDn
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query */ Gsm.a
privateint beginIndex; e%9zY{ABR%
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/** The default constructor */ e%7#e%1s
public Page(){ VjeF3pmBa
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} T/hz23nH
d@Wze[M?0
/** construct the page by everyPage jPc,+?
* @param everyPage }`76yH^c
* */ 4:s,e<Tc4v
public Page(int everyPage){ srKEtd"
this.everyPage = everyPage; 1k$5'^]^9]
} - Sn]`
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/** The whole constructor */ G) 37?A)
public Page(boolean hasPrePage, boolean hasNextPage, cF"}}c1*M
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int everyPage, int totalPage, iBKH\em/
int currentPage, int beginIndex){ w,<n5dMv
this.hasPrePage = hasPrePage; uj)fah?Wg
this.hasNextPage = hasNextPage; b<E78B+Aax
this.everyPage = everyPage; L /N%ft]!T
this.totalPage = totalPage; ,"?8
this.currentPage = currentPage; P_.AqEH
this.beginIndex = beginIndex; ))7CqN
} z6Nz)$!_i
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/** E$v!Z; A
* @return F84<='K
* Returns the beginIndex. aZq7(pen
*/ ;2aPhA
publicint getBeginIndex(){ !R[~Z7b6
return beginIndex; 8/"C0I (G
} wF*9%K'E
Y/L*0M.<
/** b4(,ls
* @param beginIndex 7GJcg7s*T
* The beginIndex to set. nIfp0U*
*/ 1q|iw
publicvoid setBeginIndex(int beginIndex){ xg'xuz$U
this.beginIndex = beginIndex; (7"CYAe:;
} qsYg%Z
sH%Ts@Pl
/** =tGRy@QV'\
* @return l,UOP[j
* Returns the currentPage. Ggbz
*/ [<wpH0lNoy
publicint getCurrentPage(){ 4K|O?MUNS
return currentPage; qCF&o7*oN
} 6$H`wDh#(&
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/** ?gMq:[XN
* @param currentPage blkPsp)m"
* The currentPage to set. xZVZYvC,t
*/ 0y2zjXM;3
publicvoid setCurrentPage(int currentPage){ 6A ptq
this.currentPage = currentPage; n8i: /ypB
} (g1Op~EM
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/** CQ7NQ^3k
* @return _.I58r
* Returns the everyPage. 1yFIIj:^|
*/ %Nx,ZD@
publicint getEveryPage(){ n"@){:{4?
return everyPage; 4P#4RB
} \$gA2r
xxld. j6
/** g@Rs.Zq
* @param everyPage 35:RsL
* The everyPage to set. $Z8riVJ7j-
*/ %\~U>3Q
publicvoid setEveryPage(int everyPage){ VLoRS)
this.everyPage = everyPage; |\94a
} e{^^u$C1.e
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/** "6v_<t`q"
* @return m[BpV.s
* Returns the hasNextPage. PzustC|
*/ K#VGG,h7Y
publicboolean getHasNextPage(){ x{/-&`F
return hasNextPage; =)a%,H
} >;%LW}
%
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/** xc7Rrh]}
* @param hasNextPage AtxC(gm 1
* The hasNextPage to set. 8~g~XUl
*/ VKg9^%#b`[
publicvoid setHasNextPage(boolean hasNextPage){ z0F55<i
this.hasNextPage = hasNextPage; {aUv>T"c
} "~Zdv}^xS
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/** PF+Or
* @return @q{.
* Returns the hasPrePage. G&4D0f
*/ c5pK%I }O
publicboolean getHasPrePage(){ 6X$nZM|g,
return hasPrePage; cBHUa}:
} Wul8ej:
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/** W>'gG}.
* @param hasPrePage @(."[O:
* The hasPrePage to set. u/N_62sk5
*/ - 8jlh
publicvoid setHasPrePage(boolean hasPrePage){ 5bol)Z9BO
this.hasPrePage = hasPrePage; cvx"XxE,
} ol`q7i.
}R:oWR
/** ")NQwT}
* @return Returns the totalPage. */vid(P77
* b'xBPTN
*/ TQvjU!>
publicint getTotalPage(){ WJ 'lYl0+7
return totalPage; QqXaXx;
} @#9xSs#
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/** }Fu2%L>
* @param totalPage [u-=<hnoa
* The totalPage to set. IEfm>N-]
*/ qzk]9`i1:
publicvoid setTotalPage(int totalPage){ c3\p@}
this.totalPage = totalPage; %H}M[_f
} U1kW1L}B
Q"qJ0f)
} J.0&gP V
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*LvdrPxU=
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 eE{
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个PageUtil,负责对Page对象进行构造: swhtlc@@
java代码: W5&KmA
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/*Created on 2005-4-14*/ #;"lBqxY`
package org.flyware.util.page; m# ^).+
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amA;
import org.apache.commons.logging.Log; g
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import org.apache.commons.logging.LogFactory; " &mwrjn"T
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/** \/r]Ra
* @author Joa dBW4%Zh
* ^9|&w.:@Q
*/ v\XO?UEJ2
publicclass PageUtil { ?Y9VviC
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privatestaticfinal Log logger = LogFactory.getLog b+71`aD0
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(PageUtil.class); o* QZf*M
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/** ay28%[Q b4
* Use the origin page to create a new page "3?:,$*
* @param page /j(<rz"j
* @param totalRecords {|Fn<&G
* @return @t8{pb;v
*/ "l6Ob
publicstatic Page createPage(Page page, int "04:1J`
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totalRecords){ &Fch{%S>
return createPage(page.getEveryPage(), kwFo*1
{
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page.getCurrentPage(), totalRecords); JWQ.Efe
} &|Vzo@D(!
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/** e?dR'*-z
* the basic page utils not including exception =5h,ZB2A
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handler IN!IjInaT@
* @param everyPage 74%Uojl"
* @param currentPage K_BF=C.k
* @param totalRecords $C6O<A
* @return page 1=Q3WMT
*/ j}$Q`7-wB1
publicstatic Page createPage(int everyPage, int c(!{_+q"
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currentPage, int totalRecords){ I~7eu&QZ
everyPage = getEveryPage(everyPage); ]WC@*3'kye
currentPage = getCurrentPage(currentPage); JA^Y:@<{/
int beginIndex = getBeginIndex(everyPage, b/'RJQSAc
a(eUdGJ
currentPage); l":Z. J
int totalPage = getTotalPage(everyPage, ?rv5Z^D'
=h}IyY@o
totalRecords); %!Ak]|[7
boolean hasNextPage = hasNextPage(currentPage, #5W-*?H
'~kAsn*/
totalPage); WiclG8l
boolean hasPrePage = hasPrePage(currentPage); \BxE0GGky
npdpKd+*K"
returnnew Page(hasPrePage, hasNextPage, !l1ycQM
everyPage, totalPage, 0%<x>O
currentPage, EU-=\Y
M\ {W &o1!
beginIndex); NhA_dskvo
} BF>3CW7
66l$}+|Zzc
privatestaticint getEveryPage(int everyPage){ <eG8xC
return everyPage == 0 ? 10 : everyPage; ,Q8)r0 c
} !&OybjQ
+MP`iuDO
privatestaticint getCurrentPage(int currentPage){ )mMHwLDwH
return currentPage == 0 ? 1 : currentPage; 4zM$I
} ,
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!FVXNl
privatestaticint getBeginIndex(int everyPage, int N!&$fhY)
/`V:;
currentPage){ bC@9
*/i
return(currentPage - 1) * everyPage;
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} 8_@#5
Ju"*>66
privatestaticint getTotalPage(int everyPage, int 7+vyN^XJ"5
_A %8oYS
totalRecords){ G&/RJLX|w
int totalPage = 0; ~L.)<{?
OJ:iQ
if(totalRecords % everyPage == 0) Z@I.socA
totalPage = totalRecords / everyPage; /HmD/E\
else EJrn4QOs
totalPage = totalRecords / everyPage + 1 ; ^gpswhp
5
h)qapC5z,
return totalPage; iCYo?>
} R8lBhLs
:3# t;
privatestaticboolean hasPrePage(int currentPage){ P+Ta|-
return currentPage == 1 ? false : true; MR@*09zP(?
} x;cjl6Acm
U`es
n?m!
privatestaticboolean hasNextPage(int currentPage, *hp3w
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7j
int totalPage){ e!67Na0X(
return currentPage == totalPage || totalPage == $DOBC@xxzT
?-P]m&nh|
0 ? false : true; W^Jh'^E
} jMvWS71
SoY=
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} j`Xe0U<
n
4:Yc@,
OE(Z)|LF
E5P?(5Nv
, wT$L3
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。 RSLMO8
<B*}W2\
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 =8?gx$r2
T=|oZ
做法如下: fT-yY`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 W[]N.d7G
gQJ y"f
的信息,和一个结果集List: 777N0,o(
java代码: );*A$C9RA
\7QAk4I~
d`U{-?N>
/*Created on 2005-6-13*/ G!J{$0.
package com.adt.bo; Q
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import java.util.List; GVT+c@Gx
&}P{w
import org.flyware.util.page.Page; !A(*?0`
$=/.oh
/** RzG<&a3B3s
* @author Joa
5gV%jQgkC
*/ 3"HpM\A{A=
publicclass Result { MXWCYi
_u$X.5Q;
private Page page; }VlX!/42
N'nI
^=
private List content; Re3vW re
SrPZ^NF
/** &[*F!=%8
* The default constructor s)dN.'5/
*/ sGjYL>*
public Result(){ hm=E~wv'L
super(); KXEDpr
} Fa`/i v
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/** {O-,JCq/
* The constructor using fields
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* 0GW(?7ZC
* @param page =k#SQ/@
* @param content [bd fp
a
*/ 9H~3&-8&
public Result(Page page, List content){ u|l]8T9L
this.page = page; 9/[3xhB4
this.content = content; Vk/CV2
} 5I,5da
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/** +Z0@z^6\
* @return Returns the content. ZOGH.`
*/ N>?R,XM
V
publicList getContent(){ ;h>s=D,r
return content; 'ojI_%9<
} CN6@g^)P
E5.3wOE
/**
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* @return Returns the page. @N?A0S/
*/ o:u *E
public Page getPage(){ 5#+G7 'k
return page; ` z<k7ig
} pj. }VF!d
V3&_ST
/** :hYV\8$
* @param content :d7Ju.*J
* The content to set. 6T>e~<^
*/ !\.%^LK1
public void setContent(List content){ xh[De}@
this.content = content; 5/-{.g
} 9$7tB
'1]Iu@?
/** |T: 'G
* @param page 4J3cQ;z
* The page to set. T/Q#V)Tp
*/ ZW\}4q;[A
publicvoid setPage(Page page){ ;`IZ&m$
this.page = page; O(BAw
} 1PLxc)LsG
} <igsO
1:S75~b-`
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c}K>#{YeB
KTX;x2r
2. 编写业务逻辑接口,并实现它(UserManager, R1Jj 3k
9l9h*Pgt
UserManagerImpl) "I.PV$Rxl
java代码: #Pi}2RBRu
:|i jCg+
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/*Created on 2005-7-15*/ A%S6&!I:(
package com.adt.service; l!z0lh-J
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import net.sf.hibernate.HibernateException; n~xh
%r;
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import org.flyware.util.page.Page; ]DcQ8D
Dg]( ?^
import com.adt.bo.Result; ghq#-N/t
xB=~3
/** OEc$ro=m*
* @author Joa <=KtRE>$
*/ m}Z=m8
publicinterface UserManager { ^b-o
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public Result listUser(Page page)throws }Xv2I$J
>*v!2=
HibernateException; iYE:o{
JGjqBuz#A*
} 0_7A
<
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;Js-27_0
=1' / ?
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(
java代码: -:w+`x?XaB
rOC2 S(m
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/*Created on 2005-7-15*/ <4!SQgL
package com.adt.service.impl; FF]xwptrx
go^?F-
dZ
import java.util.List; *T(z4RVg
=m{]Xep
import net.sf.hibernate.HibernateException; vvEr}G
9/N=7<$
import org.flyware.util.page.Page; +m Plid\
import org.flyware.util.page.PageUtil; "P O>@tY
[wS~.
import com.adt.bo.Result; Kfho:e,
import com.adt.dao.UserDAO;
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import com.adt.exception.ObjectNotFoundException; 8 /3`rEW
import com.adt.service.UserManager; FM\yf]'
}[a
/** JVO,@~~
* @author Joa G 2L?j
*/ EC*rd
publicclass UserManagerImpl implements UserManager { zqqu7.`
35/)S@
private UserDAO userDAO; 1_}*aQ
px!lJtvgo
/** iQry X(z
* @param userDAO The userDAO to set. @I{v
*/ p-d2HXo
publicvoid setUserDAO(UserDAO userDAO){ SF?Ublc!
this.userDAO = userDAO; \nQV{J
} 1k&**!S]%
VFUuG3p)
/* (non-Javadoc) &%."$rC/0b
* @see com.adt.service.UserManager#listUser *Mu X]JK
? OrRTRW
(org.flyware.util.page.Page) j*uc$hC"
*/ 5r#0/1ym!
public Result listUser(Page page)throws p$r=jF&
5#Z> }@/
HibernateException, ObjectNotFoundException { y#%*aV}|B
int totalRecords = userDAO.getUserCount(); ILsw'
if(totalRecords == 0) 9d7`R'
throw new ObjectNotFoundException #=~n>qn]
n)]]g3y2
("userNotExist"); yb)!jLnH
page = PageUtil.createPage(page, totalRecords); i9KQpWG:
List users = userDAO.getUserByPage(page); //9M~qHa"
returnnew Result(page, users); FjUf|
} 3yT7;~vPj
zoFCHsr
} 1Yj ^N"=
K5;
/
5i 56J1EC
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p#['CqP8
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 I)@b#V=
LEnm6
询,接下来编写UserDAO的代码: aZK%?c
3. UserDAO 和 UserDAOImpl: )?@X{AN&
java代码: 1+P&O4>
!3Xu#^Xxj
,yZvT7
/*Created on 2005-7-15*/ a>1_|QB.
package com.adt.dao; u19d!#g
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import java.util.List; Dwvd
{5<3./5O
import org.flyware.util.page.Page; y _Mte
f@:.bp8VB8
import net.sf.hibernate.HibernateException; xMck A<E
Qw&It
/** )vO?d~x|
* @author Joa "RZVv~BD
*/ /eZ UAxq
publicinterface UserDAO extends BaseDAO { %XIPPEHU
!1g2'
publicList getUserByName(String name)throws irg%n
6xLLIby,
HibernateException; \YV`M3O
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publicint getUserCount()throws HibernateException; W{z7h[?5,
>P@JiR<@\n
publicList getUserByPage(Page page)throws U_1syaY!
c:%ll&Xtn
HibernateException; *U[Nn5#?
'?WKKYD7N
} ,!m][
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g\Ck!KJ/y
]KsL(4PY
@vy{Q7aM
java代码: rD7L==Ld
'a}<|Et.
y.pwj~s
/*Created on 2005-7-15*/ q4'Vb
package com.adt.dao.impl; _[eAA4h
y":Y$v,P
import java.util.List; 3,x|w
8&gr}r-
5
import org.flyware.util.page.Page; #&L[?jEn
"`QI2{!l
import net.sf.hibernate.HibernateException; O@[jNs)].
import net.sf.hibernate.Query; &mG1V
+lK?)77f
import com.adt.dao.UserDAO; H%}ro.u
A7|CG[wZ
/** W.B;Dy,Y
* @author Joa 8$c_M
*/ n!nXM
public class UserDAOImpl extends BaseDAOHibernateImpl XN*?<s3
#u<^
implements UserDAO { .Mn+Bd4f
&p."`
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/* (non-Javadoc) R F)Qsa
* @see com.adt.dao.UserDAO#getUserByName Q9Y$x{R&
__F?iRrCM
(java.lang.String) U\crp
T`
*/ 7W{xK'|]
publicList getUserByName(String name)throws sHt
PO[h
GT -(r+u
HibernateException { K`BNSdEN>
String querySentence = "FROM user in class nBVR)|+M
M;14s*g
com.adt.po.User WHERE user.name=:name"; `|t X[':
Query query = getSession().createQuery r87)?-B
NXJyRAJ*%
(querySentence); Lq-Di|6q
query.setParameter("name", name); Qh3V[br
return query.list(); k|ol+
9Z
} ^KKU@ab9
1#G(
/* (non-Javadoc) =LFrV9
* @see com.adt.dao.UserDAO#getUserCount() |GDf<\
*/ SkmL X@:(
publicint getUserCount()throws HibernateException { Hy?+p{{G
int count = 0; _fVC\18T
String querySentence = "SELECT count(*) FROM VcLB0T7m\
v7V.,^6+
user in class com.adt.po.User"; o(2tRDT\_b
Query query = getSession().createQuery &WqKsH$
3Zr'Mn
(querySentence); 3eq VY0q
count = ((Integer)query.iterate().next r]C`#
P,(Tu.EPk
()).intValue(); \z/_vzz4
return count; "Yk3K^`1T.
} 1 z4s1Y
D<.zdTo
/* (non-Javadoc) ;AFF7N>&
* @see com.adt.dao.UserDAO#getUserByPage 3#IU^6l:1S
H-*"%SJ
(org.flyware.util.page.Page) uv:DO6 {
*/ SS4'yaQ
publicList getUserByPage(Page page)throws BUuU#e5
@iW^OVpp<8
HibernateException { "8bxb
String querySentence = "FROM user in class ;w^-3 U7:
%
d%KH9u
com.adt.po.User"; !PaDq+fB
Query query = getSession().createQuery &HPzm6.3
\~1>%F'op
(querySentence); L4)@lmd3
query.setFirstResult(page.getBeginIndex()) Jkc1ih`^
.setMaxResults(page.getEveryPage());
Tl.%7)
return query.list(); OT&mNE4
} 12NV
tRqg')y
} `kx+ Kc
[M^ur%H
w
Wx,}=
9Q!X~L|\S
:&]THUw
至此,一个完整的分页程序完成。前台的只需要调用 ?c vXuxCm
dMA"% R
userManager.listUser(page)即可得到一个Page对象和结果集对象 VW7
?{EL7
c'9-SY1'~
的综合体,而传入的参数page对象则可以由前台传入,如果用 1I#S?RSb
kUl:Yj=&
webwork,甚至可以直接在配置文件中指定。 2|fN*Wm
lC/4CPKtV
下面给出一个webwork调用示例: x?ajTzMv
java代码: 'xO^2m+N;
=w~phn
+OUYQM mM
/*Created on 2005-6-17*/ ,{@,dw`lUz
package com.adt.action.user; </K"\EU
|JpLMUG
import java.util.List; QfI)+pf
G3j&8[
import org.apache.commons.logging.Log; N XwQvm;q
import org.apache.commons.logging.LogFactory; EDm,Y
import org.flyware.util.page.Page; =R M=@X
py,B6UB5
import com.adt.bo.Result; w$JG:y#
import com.adt.service.UserService; t~xp&LQiY
import com.opensymphony.xwork.Action; 1|za>N6[yu
GEg8\
/** XO)|l8t#$=
* @author Joa `Gl@?9,i
*/ +4k Bd<0Y
publicclass ListUser implementsAction{ FFT h}>>
$K)9(DD
privatestaticfinal Log logger = LogFactory.getLog r?e)2l~C8j
u S$:J:Drx
(ListUser.class); r^uo7?gZ^
l\=M'D
private UserService userService; %ZF6%m0S
_)q,:g~fu
private Page page; EwSE;R -
fP41B
privateList users; J$)lYSNE
q?x.P2
/* EUvxil
* (non-Javadoc) ^Zh
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* QdM&M^
* @see com.opensymphony.xwork.Action#execute() !]tZE%?
*/ )'{:4MX
publicString execute()throwsException{ q]%c
6{w
Result result = userService.listUser(page); UR~9*`Z ,
page = result.getPage(); sR`WV6!9
users = result.getContent(); Xa._
return SUCCESS; +zpmy3Q
} sjLI^#a
hJ0)"OA5
/** ~eH+*U|\|M
* @return Returns the page. rC>')`uk
*/ *$nz<?
public Page getPage(){ t:m2[U_}
return page; L0{ehpvM
} z5CZ!"&v
f
Q.ea#xh^
/** u 89u#gCAC
* @return Returns the users. yQ>
*F
*/ >r7{e:~q
publicList getUsers(){ Yt"&8N]
return users; iw|6w,-)C
} .'Vjs2 2
p<