Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;gHcDnH)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }<2|6 {
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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 4Z{R36 {
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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 :L:] 3L
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分页支持类: uUBUUr
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java代码: 'YN:cr,V
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package com.javaeye.common.util; U;ujN 8
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import java.util.List; &% (1?\~u
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publicclass PaginationSupport { 5B1,,8P
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publicfinalstaticint PAGESIZE = 30; @!x7jPr
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privateint pageSize = PAGESIZE; A&KY7[<AC{
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privateList items; 3M^`6W[;
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privateint totalCount; =fy.'+
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privateint[] indexes = newint[0]; ^LSD_R^N
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privateint startIndex = 0; zuJ` 704
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public PaginationSupport(List items, int [m
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totalCount){ ][OkydE
setPageSize(PAGESIZE); rw@N=`4P
setTotalCount(totalCount); jt @2S
setItems(items); BlqfST#6
setStartIndex(0); ^^xzaF
} oe9S$C;$'
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public PaginationSupport(List items, int )i-`AJK-'v
%<q"&]e,
totalCount, int startIndex){ )5<dmK@
setPageSize(PAGESIZE); Vz5<Gr
setTotalCount(totalCount); +tlbO?
setItems(items); nu|?F\o!
setStartIndex(startIndex); >NpW$P{'
} HW6Cz>WxOW
8,CL>*A
public PaginationSupport(List items, int }ZwnG=7T?
&t@ $]m(
totalCount, int pageSize, int startIndex){ eEmLl(Lb
setPageSize(pageSize); jNIz:_c-~
setTotalCount(totalCount); !P6y_Frpe
setItems(items); ?K.!^G
setStartIndex(startIndex); 1Ji"z>H*
} at3YL[,[Z
e
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publicList getItems(){ p7*7V.>X
return items; =Y3 d~~
} ,*p(q/kJh~
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publicvoid setItems(List items){ x||b:2
this.items = items; lnxA/[`a
} Oo\~'I
@zix%x
publicint getPageSize(){ sg]g;U
return pageSize; @[rlwwG,
} [9p@uRE
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publicvoid setPageSize(int pageSize){ l4^8$@;s
this.pageSize = pageSize; ,6U=F#z
} 8HSGOs =8
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publicint getTotalCount(){ %N<>3c<8P
return totalCount; C|ou7g4'p
} %ZlnGr
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publicvoid setTotalCount(int totalCount){ 5_L43-
if(totalCount > 0){ o{|
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this.totalCount = totalCount; MD+eLA7
int count = totalCount / PzLV}
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pageSize; ;u%4K$
if(totalCount % pageSize > 0) JAL"On#c#0
count++; Ly/5" &HD
indexes = newint[count]; eR8>5:V_
for(int i = 0; i < count; i++){ 'ka"0~:NS{
indexes = pageSize * st CFLYox
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i; lzZ=!dG
} ZOzyf/?.
}else{ rmnnV[@o
this.totalCount = 0; 5YiBw|Z7 "
} &-Z#+>=H(
} :Z5kiEwYM
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publicint[] getIndexes(){ vf_pEkx*wD
return indexes; @]{:juD~
} tbi(e49S
_ID =]NJ_
publicvoid setIndexes(int[] indexes){ /^Lo@672
this.indexes = indexes; ,PyPRPk
} 6HR*)*>z_
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publicint getStartIndex(){ nHF
return startIndex; Jc9^Hyqu&
} $2*&\/;-E!
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publicvoid setStartIndex(int startIndex){ 'P)[=+O?t
if(totalCount <= 0) P,Rqv)}X
this.startIndex = 0; mZ
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elseif(startIndex >= totalCount) C;!h4l7L
this.startIndex = indexes P~*v}A
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[indexes.length - 1]; u]Y NF[]
elseif(startIndex < 0) +&TcTu#.`
this.startIndex = 0; /K#J63 ,
else{ :!g zx n
this.startIndex = indexes t~]oJ5%
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[startIndex / pageSize]; ~;Xkt G:
} I*i$!$Bx2
} b(gcnSzM2
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publicint getNextIndex(){ |teDe6\m
int nextIndex = getStartIndex() + 2$%0~Z5
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pageSize; ,_t}\7
if(nextIndex >= totalCount) -wV0Nv(V8
return getStartIndex(); 38q0iAH
else 'r?OzFtxh
return nextIndex; g7W\
&
} \8X8NCM
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publicint getPreviousIndex(){ FwGMrJW
int previousIndex = getStartIndex() - c'6$`nC
F1o"H/:n
pageSize; NBZ>xp[U
if(previousIndex < 0) jk}m
return0; #8jH_bi
else >pl*2M&
return previousIndex; oE4hGt5x{
} 7dU7cc
_A/ ]m4
} k-vxKrjZ/
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抽象业务类 IN9o$CZ:
java代码: MRHkQE+K@8
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/** }UWRH.;v
* Created on 2005-7-12 eL!G, W
*/ %z0@4Gq
package com.javaeye.common.business; :O}<Q
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import java.io.Serializable; |]H2a;vUJR
import java.util.List; Wh>Y_ k
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import org.hibernate.Criteria; NeyGIEP
import org.hibernate.HibernateException; /`Lki>"
import org.hibernate.Session; ( Dl68]FX
import org.hibernate.criterion.DetachedCriteria; y0'"
import org.hibernate.criterion.Projections; w8g36v*+(u
import T{lJ[M
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org.springframework.orm.hibernate3.HibernateCallback; pf`li]j'V
import ZvO:!u0+"
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org.springframework.orm.hibernate3.support.HibernateDaoS ]H[FZY
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upport; yMa5?]J
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import com.javaeye.common.util.PaginationSupport; , 0rC_)&B
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public abstract class AbstractManager extends J=U7m@))Y#
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HibernateDaoSupport { b\\?aR
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privateboolean cacheQueries = false; KXFa<^\o
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privateString queryCacheRegion; kB]|4CG{
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publicvoid setCacheQueries(boolean zj;y`ENj
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cacheQueries){ ;SVF"Uo
this.cacheQueries = cacheQueries; #UJ@P Dwil
} Ve8`5
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publicvoid setQueryCacheRegion(String z[
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queryCacheRegion){ (<.1o_Q-LU
this.queryCacheRegion = +T^m
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queryCacheRegion; wL 5).`oq
} s}9aZ
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publicvoid save(finalObject entity){ ?t}[Wi}7
getHibernateTemplate().save(entity); ]yVB66l
} XW Y0WDh:
m x,X!}
publicvoid persist(finalObject entity){ .[Sv|;x"E
getHibernateTemplate().save(entity); *<#&ne8
} a}c(#ZLs
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publicvoid update(finalObject entity){ r% '2a+}D
getHibernateTemplate().update(entity); 5#f&WL*U@
} nw5#/5xw
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publicvoid delete(finalObject entity){ I"JT3[*s
getHibernateTemplate().delete(entity); ESASsRzk
} $@&bK2@.(
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publicObject load(finalClass entity, @3S2Xb{ra1
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finalSerializable id){ I(
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return getHibernateTemplate().load l1wxs@](
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(entity, id); sq)Nn&5A
} sX_ ^H%fd
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publicObject get(finalClass entity, {fN_itn
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finalSerializable id){ d)o<R;F
return getHibernateTemplate().get JrL/LGY
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(entity, id); LbYI{|_Js
} "|Q&
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publicList findAll(finalClass entity){ BS|-E6E<
return getHibernateTemplate().find("from dadMwe_l0
w pCS]2
" + entity.getName()); VBCj.dw
} 8w*fg6,=
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publicList findByNamedQuery(finalString m#;:%.Rm
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namedQuery){ "?9fL#8f*!
return getHibernateTemplate $qrr]U
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().findByNamedQuery(namedQuery); Vd1K{rH#
}
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publicList findByNamedQuery(finalString query, =k/n
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finalObject parameter){ %mYIXsuH
return getHibernateTemplate 8m*\"_S{
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().findByNamedQuery(query, parameter); s{:
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} g*tLqV
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publicList findByNamedQuery(finalString query, <?J7Z|
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finalObject[] parameters){ b{dzbmak
return getHibernateTemplate OVh/t#On
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_#{2(
().findByNamedQuery(query, parameters); fVN}7PH7+
} $c y:G
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publicList find(finalString query){ yED^/=\)}
return getHibernateTemplate().find AeJM[fCMa
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(query); 4
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} \S@A
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publicList find(finalString query, finalObject )
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parameter){ 0Its;|
return getHibernateTemplate().find mcX akWmi
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(query, parameter); 7S7!
} Y}#^n7*w~
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public PaginationSupport findPageByCriteria i-=ff
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(final DetachedCriteria detachedCriteria){ !fV6KkV
return findPageByCriteria ^/BE=$E\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~R8yj(
} @}Z/{Z[@
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public PaginationSupport findPageByCriteria @ixX?N)V
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(final DetachedCriteria detachedCriteria, finalint ;VH]TKkk
<EUSl|6
startIndex){ "PHv~_:^R
return findPageByCriteria H.mG0x`M"E
y,>m#6hx#
(detachedCriteria, PaginationSupport.PAGESIZE, >V$#Um?AXj
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startIndex); iQIw]*h^
} ;E"mB4/)
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public PaginationSupport findPageByCriteria >y~_Hh(TSL
E! <$J^
(final DetachedCriteria detachedCriteria, finalint 9C 05
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pageSize, ~.lH)
finalint startIndex){ Z4-dF;7
return(PaginationSupport) DmrfD28j~F
. R}y"O\
getHibernateTemplate().execute(new HibernateCallback(){ bLzuaNa'
publicObject doInHibernate |K-lgrA
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(Session session)throws HibernateException { ~b[4'm@
Criteria criteria = @(?4g-*E
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detachedCriteria.getExecutableCriteria(session); D ` X6'PP
int totalCount = 8} k,!R[J
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((Integer) criteria.setProjection(Projections.rowCount pi}H.iF
5mNXWg7#]
()).uniqueResult()).intValue(); >[: 2
criteria.setProjection j*`!o/=LI
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(null); a0.3$
List items = $?-o
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criteria.setFirstResult(startIndex).setMaxResults 49$4
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(pageSize).list(); cZzZNGY^ts
PaginationSupport ps = r3_gPK
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new PaginationSupport(items, totalCount, pageSize, ^ks^9*'|j
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startIndex); F s\P/YX
return ps; cB}2(`z9
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} ,O)\,tg
}, true); ZcRm5Du~:
} 3/=QZ8HA&-
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public List findAllByCriteria(final RT"2Us]*
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DetachedCriteria detachedCriteria){ g VJ#LJ
return(List) getHibernateTemplate `UK+[`E
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().execute(new HibernateCallback(){ MEnHC'nI
publicObject doInHibernate PEt8,,x<"
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(Session session)throws HibernateException { ==Mi1Q#5C
Criteria criteria = &:#8ol(n5b
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detachedCriteria.getExecutableCriteria(session); s)8M? |[`I
return criteria.list(); Pq>[q?>?
} I 47GQho
}, true); HHTsHb{7
} >m1V9A
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public int getCountByCriteria(final 1 "7#|=1/
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DetachedCriteria detachedCriteria){ ]U1,NhZu
Integer count = (Integer) N pND/
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getHibernateTemplate().execute(new HibernateCallback(){ &E
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publicObject doInHibernate T$8~9qx
<?{}Bo0xG
(Session session)throws HibernateException { .^IhH|U
Criteria criteria = ]</4#?_
+()t8,S,
detachedCriteria.getExecutableCriteria(session); @H%=%ZwpO
return *Yu\YjLPG
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criteria.setProjection(Projections.rowCount j~*Z7iu
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()).uniqueResult(); <4e*3WSG
} kok^4VV
}, true); H"rzRd;S
return count.intValue(); nWF4[<t
} UZ\*]mxT
} kF,\bM
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用户在web层构造查询条件detachedCriteria,和可选的 T|s0qQi
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 zMYd|2bc
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PaginationSupport的实例ps。 8Cs$NUU
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ps.getItems()得到已分页好的结果集 a950M7
ps.getIndexes()得到分页索引的数组 iQ{&&>V%
ps.getTotalCount()得到总结果数 4G8nebv
ps.getStartIndex()当前分页索引 C{hcK 1-K
ps.getNextIndex()下一页索引 M1^C8cz
ps.getPreviousIndex()上一页索引 soq".+Q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 5nx<,-N*BP
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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 yD"0=\
2>}\XKF).
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: x]R(twi
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首先,为了实现分页查询,我封装了一个Page类: WTD49_px
java代码: 6Z7pztk
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/*Created on 2005-4-14*/ ytve1<.Ff
package org.flyware.util.page; hiMyFvA4
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/** IjDT'p_
* @author Joa crNjI`%tw
* `N,Vs n"
*/ a}Fk x
publicclass Page { uPFHlT
II-$WJy
/** imply if the page has previous page */ B8UZ9I$n
privateboolean hasPrePage; inB PT~y
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/** imply if the page has next page */ [t.%baF
privateboolean hasNextPage; *F
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/** the number of every page */ "@{4.v^}!
privateint everyPage; /:y2Up-
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/** the total page number */ Sn(l$wk=
privateint totalPage; #A3v]'7B
~n/Aq*
/** the number of current page */
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privateint currentPage; J`r,_)J"2
{,Bb"0 \
/** the begin index of the records by the current L-z;:Ztk
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query */ M20Bc, VI
privateint beginIndex; 6)wy^a|pb
i-k >U}[%
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/** The default constructor */ If-,c^i
public Page(){ f]ue#O
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} Ns2,hQFc
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/** construct the page by everyPage $U>/i@ D
* @param everyPage _hy{F%}
* */ ;+i'0$;*w
public Page(int everyPage){ l`b1%0y
this.everyPage = everyPage; Uvh~B^6
} 7$ =Y\P
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/** The whole constructor */ Y$`eg|$
public Page(boolean hasPrePage, boolean hasNextPage, qX5yN| A4
*#1y6^
fVDDYo2\
int everyPage, int totalPage, %AG1oWWc>.
int currentPage, int beginIndex){ #v4LoNm
this.hasPrePage = hasPrePage; *K(k Kph
this.hasNextPage = hasNextPage; +}^|dkc
this.everyPage = everyPage; W|25t)cJ8h
this.totalPage = totalPage; ^sifEgG *d
this.currentPage = currentPage; Qz@IK:B}
this.beginIndex = beginIndex; bo@,4xw
} E dn[cH7
(#6AKr9K
/** 7v_i>_m]
* @return JiFA]M`^Q
* Returns the beginIndex. S\e&?Y`
*/ qKdS7SoS
publicint getBeginIndex(){ :zdEq")v
return beginIndex; 2W^B{ZS;
} HDmx@E.@
jzs.+dAg
/** IKi{Xh]\
* @param beginIndex 9u,8q:I.?
* The beginIndex to set. KVB0IXZC~
*/ w66v\x~
publicvoid setBeginIndex(int beginIndex){ u8YB)kG
this.beginIndex = beginIndex; 7tSJniB
} /O|:{LQ
)Hbb&F
/** {O^TurbTFA
* @return mn]-rTr
* Returns the currentPage. t;8\fIW5
*/ 8Q2]*%
publicint getCurrentPage(){ T><{ze
return currentPage; ,~4H{{<j
} X^}A*4j
'K@-Z]
/** TUh&d5a9H
* @param currentPage ]^=|Zd-
* The currentPage to set. qib7Z]j
*/ KRYcCn
publicvoid setCurrentPage(int currentPage){ fb\DiKsW
this.currentPage = currentPage; ugYw<
} ep+
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/** ?Z q_9T7
* @return 4%
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* Returns the everyPage. AL$W +')
*/ bGv*-;*
publicint getEveryPage(){ 'p%=<0vrr
return everyPage; ZJ;LD*
} *'D=1{WZ!
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/** w
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* @param everyPage \6sqyWI
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* The everyPage to set. zZ%DtxUoU.
*/ }A]BpSEP
publicvoid setEveryPage(int everyPage){ ,c>N}*6h=W
this.everyPage = everyPage; ^q
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} FigR1/3o'6
^[k0k(_
/** 0rD#s{?
* @return mjb{~
* Returns the hasNextPage. Nbt GlSs8
*/
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publicboolean getHasNextPage(){ >$\Bu]{1
return hasNextPage; z3a-+NjD m
} WsR+Np@c
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/** 5[C ~wvO
* @param hasNextPage n` q2s'Pc
* The hasNextPage to set. rH&G<o&,
*/ aD9rp
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publicvoid setHasNextPage(boolean hasNextPage){ 79ckLd9
this.hasNextPage = hasNextPage; Sk:2+inU
} AoYaVlKG8
o(*F])d;
/** "O*x' XhN
* @return |; $Bb866/
* Returns the hasPrePage. J$F nm\
*/ c<wavvfUo
publicboolean getHasPrePage(){ P;vxT}1
return hasPrePage; e+'%!w"B
} MIq"Wy|Zs
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/** G@gh#[b
* @param hasPrePage jd 1jG2=f
* The hasPrePage to set. %j7:tf=
*/ k=[pm5ZvT~
publicvoid setHasPrePage(boolean hasPrePage){ @%1IkvJV
this.hasPrePage = hasPrePage; MRfb[p3Cx
} -DP*q3
0VN7/=n|
/** ,_jC$
* @return Returns the totalPage. @x1%)1
* @o>EBZ7MS
*/ 22
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publicint getTotalPage(){ .2.qR,"j
return totalPage; u-JpI-8h
} #)s!}X^
2*[QZ9U[@
/** wv?RO*E
* @param totalPage ExVDkt0
* The totalPage to set. i?>tgmu.
*/ 0:"2MSf>
publicvoid setTotalPage(int totalPage){ mdW~~-@H
this.totalPage = totalPage; F";.6%;AC
} %MZP)k,&U
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} Xc*U+M>U
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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 rh!;|xB|+
7"4z+w
个PageUtil,负责对Page对象进行构造: HeLG?6
java代码: p@~ic#X
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/*Created on 2005-4-14*/ O^Q,-=tA\
package org.flyware.util.page; c6&Q^p|CF
0
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import org.apache.commons.logging.Log; -fy9<
import org.apache.commons.logging.LogFactory; B4h5[fPX
o.m:3!RW
/** B(_WZa!
* @author Joa k()$:-V
* 0|c}p([~
*/ j+rG7z){K
publicclass PageUtil { r^0F"9eOL
+1rkq\{l
privatestaticfinal Log logger = LogFactory.getLog 7b[wu~'(
n
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(PageUtil.class); ),(V6@Z?
/( hUfYm0
/** iEm ?
* Use the origin page to create a new page E5</h"1
* @param page M5g\s;y;
* @param totalRecords SJ?cI!=x
* @return MSw$_d
*/ %Ip*Kq-
publicstatic Page createPage(Page page, int GbI-SbE
#wY0D_3@1
totalRecords){ _%/}>L>-`8
return createPage(page.getEveryPage(), YJ_\Ns+Ow
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page.getCurrentPage(), totalRecords); %<0eA`F4
} z//VlB
?'s6Xmd
/** s58C2
* the basic page utils not including exception :o46rBs
q?):oJ
handler KC`q#&dt
* @param everyPage */^QH@ P
* @param currentPage 'Gl&Pa1g?
* @param totalRecords kD5!}+y
* @return page |'d>JT:
*/ I_1e?\
publicstatic Page createPage(int everyPage, int n]}W``=7
?t](a:IX
currentPage, int totalRecords){ x3 >
everyPage = getEveryPage(everyPage); /w (e
currentPage = getCurrentPage(currentPage); q_kdCO{:df
int beginIndex = getBeginIndex(everyPage, qIIJ4n
8CbXMT
currentPage); F@ Swe
int totalPage = getTotalPage(everyPage, (wRgus
6$\jAd|
totalRecords); _8,()t'"
boolean hasNextPage = hasNextPage(currentPage, {vEOn-(7
m_+sR!\H8
totalPage); XI<L;
boolean hasPrePage = hasPrePage(currentPage); ag-f{UsTy
H@bf'guA|B
returnnew Page(hasPrePage, hasNextPage, nKa$1RMO
everyPage, totalPage, 2*w0t:Yxe
currentPage, 1y#D?R=E
3cdTed-MIh
beginIndex); a2IgC25
} ryB}b1`D
f| _u7"OX
privatestaticint getEveryPage(int everyPage){ 5"XC$?I<}
return everyPage == 0 ? 10 : everyPage; PHOP%hI$
} 0k)rc$eDF+
Q7Iw[=;\
privatestaticint getCurrentPage(int currentPage){ yAL[[
return currentPage == 0 ? 1 : currentPage; GZI`jS"lU
} 'k;rH!R
-Eu6U`"(
privatestaticint getBeginIndex(int everyPage, int |L2SFB?d=
;OqB5qd
currentPage){ CI353-`
return(currentPage - 1) * everyPage; MZ+^-@X
} ls@i".[
h8Yx#4
privatestaticint getTotalPage(int everyPage, int 7d LuX
#(An6itl
totalRecords){ IxLhU45
int totalPage = 0; q9Y9w(
^nbnbU4'
if(totalRecords % everyPage == 0) iQDx{m3]
totalPage = totalRecords / everyPage; {|I;YDA
else Z}$TKO*u
totalPage = totalRecords / everyPage + 1 ; )W/;=K
cufH?Xg<
return totalPage; UMAgA!s
} p
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privatestaticboolean hasPrePage(int currentPage){ _S>JKz
return currentPage == 1 ? false : true; I(S`j[U
} 4R18A=X
Ym3\pRFiD
privatestaticboolean hasNextPage(int currentPage, 94B\5I}
hzk cP
int totalPage){ UQ{L{H
return currentPage == totalPage || totalPage == /p8dZ+X
O,Cb"{qH8
0 ? false : true; nBk)WX&[K
} u\C
lP#
`
,SiA-3*
H\TI[JPAl
} v`M3eh@$A
dKdj`wB
|yx6X{$k
8F._9U-EN
Y "/]|'p
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。 ~ 4kc/a
#B4%|v;`E?
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 +HBd
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8F'x=lIO
做法如下: s&RVJX>Rt
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6Vz9?puD
\[y`'OD~
的信息,和一个结果集List: PYGRsrcFd#
java代码: nDHTV!]<
oH_;4QU4y
=3L;Z[^9
/*Created on 2005-6-13*/ x QIq^/F0
package com.adt.bo; @)fd}tV
ouuuc9x]
import java.util.List; J:Qa5MTWp
Z'\h
import org.flyware.util.page.Page; 2AMo:Jqv
u:=7l
/** q^Y-}=w
* @author Joa *{L)dW+:
*/ H !$o$}A
publicclass Result { #w' kV#
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private Page page;
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cLLbZ=`
private List content; iv4H#rJ
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/** 2.l:O2<
* The default constructor tNbN7yI
*/ !6*"(
public Result(){ S[J}UpV
super(); |&zz,+ E
} ee^{hQi
?!` /m|"
/** 0@%v1Oja
* The constructor using fields *2,VyY
* eS~LF.^Jw
* @param page -w"VK|SGm
* @param content 5fd]v<
*/ _sTROd)Vh
public Result(Page page, List content){ )8$=C#qC[
this.page = page; ^G}47(
this.content = content; tM'P m
} =Jyu4j *}
iMDM1}b
/** ~kEI4}O
* @return Returns the content. uFinv2Z'
*/ ~v|>xqWV
publicList getContent(){ `u&Rsz&^
return content; vVFy*#I#_[
} +l<5#pazx
V<T9&8l+:
/** D=-SO
+
* @return Returns the page. <+?7H\b
*/ mc? Vq
public Page getPage(){ dtRwTUMe?
return page; woGAf)vV#
} 0"28'
9
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/** x"~8*V'0
* @param content .uMn0PE
* The content to set. o <pf#tifv
*/ + |n*b
public void setContent(List content){ JR@`2YP-
this.content = content; hG12ZZ D
} /rnu<Q#iH
f'EuY17w
/** 0dE@c./R i
* @param page VJ]JjB
j
* The page to set. Z8K?
*/ 42$VhdG
publicvoid setPage(Page page){ -"'j7t:
this.page = page; F%@aB<Nu
} BBwy,\o#
}
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+M\`#i\g>
q_A!'sm@)
2. 编写业务逻辑接口,并实现它(UserManager, 3TeY%5iVt
vqDu(6!2
UserManagerImpl) su{poQ}K
java代码: P3+5?.p.
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/*Created on 2005-7-15*/ }v}P
.P
package com.adt.service; R;&AijS8
^
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import net.sf.hibernate.HibernateException; jFL #s&ft
P}n_IV*@
import org.flyware.util.page.Page; ,Z&xNBX
-#u=\8
import com.adt.bo.Result; %)zodf
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/** Ug>~Rq]
* @author Joa ;g+N&)n
*/ [+T.at
publicinterface UserManager { 4xjP iHd<
h-q3U%R4}@
public Result listUser(Page page)throws [9evz}X
fI ?>+I5
HibernateException; C~,a!qY
! >(7+B3E*
} GfoLae
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@\0ez<.p}
bnf'4PAt
/?5 1D@
java代码: +Vb.lH[av
LDgrR[
naG=Pq<
/*Created on 2005-7-15*/ ?+@n3]`0
package com.adt.service.impl; Lb:g4A"
qeV fE_<
import java.util.List; @ym v< Mo
QwW&\h[8?
import net.sf.hibernate.HibernateException; y-'$(x
:~"CuB/
import org.flyware.util.page.Page; g:g\>@Umo
import org.flyware.util.page.PageUtil; -$,TMqM
t3 8m'J :>
import com.adt.bo.Result; BO~0ON0
import com.adt.dao.UserDAO; HVR /7&g
import com.adt.exception.ObjectNotFoundException; ry`Ho8N
import com.adt.service.UserManager; x-WmMfcz&
ak$f"py
x
/** X`kk]8=
* @author Joa lA|
5E?
*/ oK6tTK
publicclass UserManagerImpl implements UserManager { a!6{:8Zi0
deBY5|
private UserDAO userDAO; wN_Vfb
MU@UfB|;u
/** 44ek
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* @param userDAO The userDAO to set. W9 GxXPA
*/ !Q2d(H>
publicvoid setUserDAO(UserDAO userDAO){ XRM_x:+]
this.userDAO = userDAO; $v4.sl:x
} JFcLv=U
q6McG HT
/* (non-Javadoc) &N2N6&Ta/
* @see com.adt.service.UserManager#listUser ;#g"(
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(org.flyware.util.page.Page) kyR:[+je
*/ uw>Ba %5
public Result listUser(Page page)throws g1/:Q%R,
l%k\JY-
HibernateException, ObjectNotFoundException { 7OcWC-<
int totalRecords = userDAO.getUserCount(); `x+ B+)0X
if(totalRecords == 0) *'Sd/%8{
throw new ObjectNotFoundException n`? py
!,wIQy_e4
("userNotExist"); o5Dk:Bw
page = PageUtil.createPage(page, totalRecords); x[FJgI'r
List users = userDAO.getUserByPage(page); lHN5Dr
returnnew Result(page, users); sXLq*b?
} ^bGNq
X
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} BRw .]&/
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.5^cb%B*
^n*)7K[
f%is~e~wc
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Uf:`
R/~p>apg8
询,接下来编写UserDAO的代码: 6dq(T_eG
3. UserDAO 和 UserDAOImpl: ne>pOK<vZ
java代码: Nyku4r0
(yH'{6g\
[^WC lRF
/*Created on 2005-7-15*/ @6Y?\Wx$w
package com.adt.dao; v [wb~uw\
:}He\V
import java.util.List; 9P1OP Xv*p
(!ux+K
import org.flyware.util.page.Page; )tC5Hijq,
8}I$'x
import net.sf.hibernate.HibernateException; ~Otq %MQ
#{\J
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/** FvaUsOy"
* @author Joa [>jbhV'
*/ pR*VdC _mY
publicinterface UserDAO extends BaseDAO { K^
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publicList getUserByName(String name)throws u(z$fG:g
qk%;on&`
HibernateException; ih58<Up5
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publicint getUserCount()throws HibernateException; S5gyr&dm
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publicList getUserByPage(Page page)throws {DV_*5
\T4v|Pw\
HibernateException; y_*
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} Y>dF5&(kb
/K+r?
]kf
rJ`!: f
p)KheLiZ
&y\prip
java代码: Gw}%{=D9
n<Z({\9&H
tIWmp30S
/*Created on 2005-7-15*/ |6.l7u?d
package com.adt.dao.impl; p2hB8zL
=mO vs
import java.util.List; GA$V0YQX
`LrHKb
aP
import org.flyware.util.page.Page; W,K;6TZhh
Ansk,$
import net.sf.hibernate.HibernateException; 1$xNUsD2
import net.sf.hibernate.Query; h1j!IG
ty8q11[8
import com.adt.dao.UserDAO; "Bh}}!13
T-'OwCB1q
/** )MtF23k)g
* @author Joa w^\52
*/ T`9lV2x*P
public class UserDAOImpl extends BaseDAOHibernateImpl .iYJr;9`d
@KXV%a'
implements UserDAO { :N:yLd} &
KN^=i5K+Y
/* (non-Javadoc) qEyyT[:
* @see com.adt.dao.UserDAO#getUserByName Z_LFIz*c
^P[e1?SZG
(java.lang.String) piJu+tUy
*/ ~Q Oe##
publicList getUserByName(String name)throws F|IAiE
lS"T4 5
HibernateException { Jf{*PgP
String querySentence = "FROM user in class 0CWvYC%e
6gL#C&
com.adt.po.User WHERE user.name=:name"; C(eTR1
Query query = getSession().createQuery a4mn*,
JYMiLph<
(querySentence); YDIG,%uv
query.setParameter("name", name); pI1-cV,`
return query.list(); ;dkYf24
} T]^62(So
Fe# 1
/* (non-Javadoc) 9>=;FY
* @see com.adt.dao.UserDAO#getUserCount() 9"N~yKa`"K
*/ B~'vCuE
publicint getUserCount()throws HibernateException { Q3XpHnufu+
int count = 0; 1rNzJ;'
String querySentence = "SELECT count(*) FROM )\1@V+!E%
'50OgF'
user in class com.adt.po.User"; [T|aw1SoN
Query query = getSession().createQuery t=BUN
N+9VYH"*
(querySentence); !eGC6o}f
count = ((Integer)query.iterate().next E:,/!9n
sv2A-Dld
()).intValue(); Q1T$k$n
return count; IDad9 Bx
} ]vz%iv_
fJ=0HNmX
/* (non-Javadoc) sSr&:BOsi
* @see com.adt.dao.UserDAO#getUserByPage $|zX|
d8DV[{^
(org.flyware.util.page.Page) f- K+]aZ)
*/ V )3KS-
publicList getUserByPage(Page page)throws ^\hG"5#
\q>bs|2
HibernateException { DRSr%d
String querySentence = "FROM user in class -zCH**y%1
w0[6t#$F
com.adt.po.User"; ZFA`s
qT
Query query = getSession().createQuery *2ZjE!A
CLxynZ\ ;
(querySentence); Bm:98? [
query.setFirstResult(page.getBeginIndex()) 3RigzT3
.setMaxResults(page.getEveryPage()); 59 h]UX=
return query.list(); kC:uG0sW
} nB_?ckj,
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k2
} raW>xOivR
g!|=%(G=
k
9_`(nx
^dI424
kPKB|kP\
至此,一个完整的分页程序完成。前台的只需要调用 ! :Y:pu0
*Hg>[@dP0
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;
8_{e3s
LHyB3V
的综合体,而传入的参数page对象则可以由前台传入,如果用 'I`&Yo~c9
`oAW7q)~
webwork,甚至可以直接在配置文件中指定。 zZ:>do\2
bpOYHc6,*`
下面给出一个webwork调用示例: 'g">LQ~a+
java代码: ):P?
e-~N"
_H9 MwJ
/*Created on 2005-6-17*/ d|jNf</`
package com.adt.action.user; #"}JdBn
|+{)_?
import java.util.List;
&U{#Kt5q
C/_ZUF(V
import org.apache.commons.logging.Log; @hl.lq
import org.apache.commons.logging.LogFactory; jxP;>K7O
import org.flyware.util.page.Page; fPU`/6
k}S :RK
import com.adt.bo.Result; goLL;AL
import com.adt.service.UserService; {k(g]#pP
import com.opensymphony.xwork.Action; hMa]B*o/-
y>S.?H:P
/** W}nlRbN?
* @author Joa
nI[os
*/ >R|/M`<ph
publicclass ListUser implementsAction{ n"$jG:AQJ
R%Hi+#/dr-
privatestaticfinal Log logger = LogFactory.getLog m\;R2"H%
M+-*QyCFK
(ListUser.class); &C:IX\
QfmJn((
private UserService userService; "N;`1ce
?K1/ <PE+
private Page page; "H2EL}3/]
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privateList users;
mR!1DQ.\<
e*sfPHt
/* 1&\0:vA^Y
* (non-Javadoc) ;[(oaK@+n
* y$;/Vm_'
* @see com.opensymphony.xwork.Action#execute() []D&bYpv
*/ t1]K<>g
publicString execute()throwsException{ md+nj{Ib
Result result = userService.listUser(page); 9/9j+5}+
page = result.getPage(); '_<{p3M
users = result.getContent(); sXqz+z$*
return SUCCESS; bkRLC_/d
} n*o-Lo+Fe.
f0!))/rSD
/** __uA}fZp
* @return Returns the page.
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*/ /pm]BC
public Page getPage(){ 97Lte5c6r
return page; rr/B=O7
} XWnVgY s
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/** {vs
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* @return Returns the users. |U~<3.:m:
*/ lVd^
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publicList getUsers(){ 84$nT>c
return users; ?xA:@:l/
} 02Y]`CXj
~Cbc<[}
/** ,y1PbA0m
* @param page #
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b
* The page to set. xg30xC[
*/ Gw=B:kGk
publicvoid setPage(Page page){ ?yZ+D z\
this.page = page; j 7fL7:,T
} $yN{-T"
K'55O&2
/** #:jHp44J
* @param users V4hiGO[
* The users to set. Fiv3 {.
*/ ,ZaRy$?
publicvoid setUsers(List users){ {SOr#{1z*
this.users = users; X1,I
} GC<l#3+
XND|h#i8
/** B`YTl~4
* @param userService LU
\i0|i|
* The userService to set. #r$cyV!k
*/ ks&*O!h
publicvoid setUserService(UserService userService){ Ki4r<>\l{H
this.userService = userService; F7A=GF'
} ZLc -RM
} %}[i'rT>
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}\hVy(\c
x`U^OLV
d+<G1w&