Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6"+bCx0:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 AX )dZdd
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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 v}^uN+a5
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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 WO+>W+|N
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分页支持类: !JjNm*F[
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java代码: `DP4u\6_
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package com.javaeye.common.util; DwXSlsN3v
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import java.util.List; {=y~O
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publicclass PaginationSupport { RUV:
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publicfinalstaticint PAGESIZE = 30; 3 k)P*ME#
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privateint pageSize = PAGESIZE; zids2/_*
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privateList items; =G1
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privateint totalCount; ;J?zD9
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privateint[] indexes = newint[0]; a0B,[i
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privateint startIndex = 0; XSo$;q\
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public PaginationSupport(List items, int 3*<~;Z' z4
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totalCount){ OjY#xO+'
setPageSize(PAGESIZE); roWg~U(S
setTotalCount(totalCount); X>s'_F?
setItems(items); inv 5>OeG
setStartIndex(0); zVtNT@1K>u
} rp,PhS
{
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public PaginationSupport(List items, int !XrnD#
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totalCount, int startIndex){ K<D=QweOon
setPageSize(PAGESIZE); 9uA2M!~i2
setTotalCount(totalCount); ~HyqHxy
setItems(items); /m+\oZ
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setStartIndex(startIndex); ZHOh(
} UhF+},gU
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public PaginationSupport(List items, int :~dI2e\:
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totalCount, int pageSize, int startIndex){ ]$
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setPageSize(pageSize); R"k}wRnxY
setTotalCount(totalCount); Q.])En >i
setItems(items); C\C*'l6d
setStartIndex(startIndex); N'e3<
} `F
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publicList getItems(){ H+2m
return items; y6 _,U/9
} XCU>b[Cj,
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publicvoid setItems(List items){ >z1q\cz
this.items = items; DAt Zp%
} ]W>kbHImz
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publicint getPageSize(){ B&k"B?9mL
return pageSize;
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} xHY#"
` p)$7!
publicvoid setPageSize(int pageSize){ '-5Q>d~&h
this.pageSize = pageSize; (*\*7dIo
} g4
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publicint getTotalCount(){ =]yzy:~ey
return totalCount; ]M#OS$_O@
} } :8{z`4H
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publicvoid setTotalCount(int totalCount){ gu~F(Fb'
if(totalCount > 0){ 1'{A,!
this.totalCount = totalCount; mUW4d3tE
int count = totalCount / Ps!~miN|>
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pageSize; pN
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if(totalCount % pageSize > 0) _R?:?{r,
count++; Nn%[J+F
indexes = newint[count]; 0pu=,
for(int i = 0; i < count; i++){ K_X10/#b&
indexes = pageSize * bW9a_m yE
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i; p%+uv\Ix
} i{
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}else{ N4JJA+
this.totalCount = 0; Fs,#d%4 @%
} mlmp'f
} wZ_k]{J
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publicint[] getIndexes(){ R!8 qkG
return indexes; KPcOW#.T
} utDjN"
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publicvoid setIndexes(int[] indexes){ ^t'mfG|DV
this.indexes = indexes; }c$@0x;YQ
} ~ojH$=K>d
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publicint getStartIndex(){ L(bYG0ZI5C
return startIndex; &2EimP
} =I}8-AS~V
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publicvoid setStartIndex(int startIndex){ ca}, tov&
if(totalCount <= 0) pSvqGJU3
this.startIndex = 0; >*A"tk#oR
elseif(startIndex >= totalCount) bvK fxAih
this.startIndex = indexes ?7Y6: zo$^
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[indexes.length - 1]; 6/Pw'4H9$
elseif(startIndex < 0) Ob"48{w$
this.startIndex = 0; P'dH*}H
else{ /kLG/ry8l:
this.startIndex = indexes {|;5P.,l
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[startIndex / pageSize]; $Z!$E,@c
} VX!UT=;
} $i^#KZ}-WK
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publicint getNextIndex(){ 0KQDw
int nextIndex = getStartIndex() + =%O@%v
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pageSize; t=IpVl!
if(nextIndex >= totalCount) U49#?^?
return getStartIndex(); nsRZy0@$t
else ]W-7 U_
return nextIndex; @.PVUP
} )_vE"ryThA
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publicint getPreviousIndex(){ ?-y!FD}m&
int previousIndex = getStartIndex() - [HV>4,,3"
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pageSize; 1h"CjOp,7
if(previousIndex < 0) XpFoSW#K
return0; $!(J4v=X
else X/5\L.g2
return previousIndex; 7(q EHZEr
} ]7*Z'E
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抽象业务类 9{{|P=
java代码: tAPr4n!
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/** 9rB,7%@EL
* Created on 2005-7-12 Qj?qWVapA
*/ Z/|oCwR
package com.javaeye.common.business; QWo_Zg0"
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import java.io.Serializable; w
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import java.util.List; ),G?f {`!
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import org.hibernate.Criteria; y%y F34
import org.hibernate.HibernateException; @AXRKYQ{t
import org.hibernate.Session; /~,|zz
import org.hibernate.criterion.DetachedCriteria; Po%+:0oX
import org.hibernate.criterion.Projections; nX@lR~g%F
import A]z~Dw3
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org.springframework.orm.hibernate3.HibernateCallback; PRs[!EB6
import %s+H& vfQs
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org.springframework.orm.hibernate3.support.HibernateDaoS :YZqrcr}
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upport; B,@<60u
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import com.javaeye.common.util.PaginationSupport; (QO8_
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public abstract class AbstractManager extends >i`V-" x
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HibernateDaoSupport { #cN0ciCT'
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privateboolean cacheQueries = false; GI&XL'K&
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privateString queryCacheRegion; U]Iypl`l
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publicvoid setCacheQueries(boolean @Axwj
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cacheQueries){ &"D *
this.cacheQueries = cacheQueries; u7rA8u|TO
} cULASS`,
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publicvoid setQueryCacheRegion(String tBtG- X2
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queryCacheRegion){ r<Il;?S6
this.queryCacheRegion = \#(3r1(
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queryCacheRegion; $1QQidB
} C%s+o0b
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publicvoid save(finalObject entity){ CM}1:o<<N
getHibernateTemplate().save(entity); '$5.{o`s*1
} B{\cV-X$0
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publicvoid persist(finalObject entity){ ~$#"'Tl4J
getHibernateTemplate().save(entity); \q2#ef@2
} QZcdfJck=+
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publicvoid update(finalObject entity){ 8>Y
getHibernateTemplate().update(entity); |5uvmK
} kB|jN~
X!} t``
publicvoid delete(finalObject entity){ XcoV27
getHibernateTemplate().delete(entity); 2$>"4
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} #~A (%a
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publicObject load(finalClass entity, 8MHYk>O~{G
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finalSerializable id){ Eei"baw/
return getHibernateTemplate().load hdL/zW7]
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(entity, id); pwg$% lv
} [>5<&[A
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publicObject get(finalClass entity, Kjw4,z%\94
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finalSerializable id){ +mM=`[Z`??
return getHibernateTemplate().get 9FB[`}
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(entity, id); P5u
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} \8Mn[G9TL
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publicList findAll(finalClass entity){ :}QBrd
return getHibernateTemplate().find("from ==zt)s.G(+
tUS)1*{_
" + entity.getName()); sVk+E'q
} VrV
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publicList findByNamedQuery(finalString \rXmWzl{
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namedQuery){ (IlHg^"
return getHibernateTemplate 9g*O;0 uz
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().findByNamedQuery(namedQuery); 4&r5M
} ?hqHTH:PU
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publicList findByNamedQuery(finalString query, 1u?h4wC
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finalObject parameter){ vrRbUwL!
return getHibernateTemplate B,Pbm|U1
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().findByNamedQuery(query, parameter); {1 VHz])I
} 75@!j[QL<
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publicList findByNamedQuery(finalString query, CSKOtqKQ)
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finalObject[] parameters){ `SFA`B)[5@
return getHibernateTemplate 9v\x&h
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().findByNamedQuery(query, parameters); U2v;[ >=]
} noSkKqP
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publicList find(finalString query){ Rz sgPk
return getHibernateTemplate().find qPI\Y3ZU
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(query); ~]sj.>P
} pUcN-WA
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publicList find(finalString query, finalObject m:6^yfS
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parameter){ pZE}<EX
return getHibernateTemplate().find +9^V9]{Vo
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(query, parameter); ^sF/-/ {?U
} HbOLf
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public PaginationSupport findPageByCriteria C F,-l
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(final DetachedCriteria detachedCriteria){ dd+hX$,
return findPageByCriteria `EXo =Dqc
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8O[br@h:5
} p*NKM}
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public PaginationSupport findPageByCriteria {yzo#"4Oy
{"dvU"y)\
(final DetachedCriteria detachedCriteria, finalint `4SwdW n
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startIndex){ <`Xt?K
return findPageByCriteria vVbBg; {
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(detachedCriteria, PaginationSupport.PAGESIZE, \ u*R6z
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startIndex);
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} Qi= pP/Y
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public PaginationSupport findPageByCriteria }R9>1u}6
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(final DetachedCriteria detachedCriteria, finalint DqJzsk'd3
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pageSize, ^XgBkC~
finalint startIndex){ al{}_1XoU
return(PaginationSupport) Fa0NHX2:
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getHibernateTemplate().execute(new HibernateCallback(){ p
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publicObject doInHibernate ]as+gZ8
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(Session session)throws HibernateException { s~NJy'Y
Criteria criteria = D_Zt:tzO
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detachedCriteria.getExecutableCriteria(session); PL|ea~/
int totalCount = f
q&(&(|
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((Integer) criteria.setProjection(Projections.rowCount [BTOs4f
$xqX[ocor
()).uniqueResult()).intValue(); df)S}}#H
criteria.setProjection ="('
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(null); X/f?=U
List items = O~OM.:al&
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criteria.setFirstResult(startIndex).setMaxResults Zs|m_O G
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(pageSize).list(); B'-n
^';
PaginationSupport ps = <u}[_
@:/H)F^x
new PaginationSupport(items, totalCount, pageSize, P
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startIndex); O?f?{Jsx
return ps; Gm[XnUR7V
} 2AXf'IOqE
}, true); P]0/ S
} d$HPpi1LL
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public List findAllByCriteria(final @Yw>s9X
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DetachedCriteria detachedCriteria){ 4C }#lW9
return(List) getHibernateTemplate {#,?K
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().execute(new HibernateCallback(){ tfdb9#&?
publicObject doInHibernate Z_4|L+i<{
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(Session session)throws HibernateException { ;TL>{"z`x
Criteria criteria = 1b<[/g9
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detachedCriteria.getExecutableCriteria(session); Tq,dlDDOR
return criteria.list(); S|O#KE
} YRyaOrl$<
}, true); *{(tg~2'(
} v$Xoxp
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public int getCountByCriteria(final t]hfq~Ft
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DetachedCriteria detachedCriteria){
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Integer count = (Integer) ,7)zavA
};g<|v*o
getHibernateTemplate().execute(new HibernateCallback(){ GO3KKuQ=
publicObject doInHibernate Uka(Vr:
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(Session session)throws HibernateException { SNC)cq+{
Criteria criteria = L0qL\>#ejr
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detachedCriteria.getExecutableCriteria(session); mM'uRhO+
return 3F$N@K~s
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criteria.setProjection(Projections.rowCount |Es,$
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()).uniqueResult(); M63t4; 0A
} Ap> H-/C
}, true); Q"K`~QF"
return count.intValue(); ,4r 4 <
} :464~tHI[`
} |Y30B,=M
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用户在web层构造查询条件detachedCriteria,和可选的 19i=kdH
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;Q<2Y#
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PaginationSupport的实例ps。 *t`=1Ioj
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ps.getItems()得到已分页好的结果集 HE-ErEtGB
ps.getIndexes()得到分页索引的数组 q:mqA$n
ps.getTotalCount()得到总结果数 6%MM)Vj+u
ps.getStartIndex()当前分页索引 \^dYmU
ps.getNextIndex()下一页索引 :ay`Id_tm
ps.getPreviousIndex()上一页索引 ctR^"'u
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 VP^{-mDph
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 " ,]A.,
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一下代码重构了。 8aVj@x$'
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我把原本我的做法也提供出来供大家讨论吧: rEjEz+wu
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首先,为了实现分页查询,我封装了一个Page类: X(Lz&fkd
java代码: )Mh5q&ow
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/*Created on 2005-4-14*/ c@$W]o"A
package org.flyware.util.page; BX2}ar
v %S$5
/** P%ZU+ET
* @author Joa )jMk~;'r
* pz]KUQ
*/ k>#-NPU$
publicclass Page { uk3PoB^>
*enT2Q
/** imply if the page has previous page */ US&:UzI.
privateboolean hasPrePage; |al'_s}I
B]PG
/** imply if the page has next page */ I9YMxf>nI
privateboolean hasNextPage; >viLvDng
)_K:A(V>
/** the number of every page */ 1r<'&f5
privateint everyPage; T/q*k)IoR
nz Klue
/** the total page number */ oSH]TL2@Cd
privateint totalPage; WB" 90!
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/** the number of current page */ sd
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privateint currentPage; B";Dj~y
aK8X,1g%)
/** the begin index of the records by the current @Dd3mWKq
on f7V
query */ Olr'n% }
privateint beginIndex; MYUL y2)
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/re0"!0y
/** The default constructor */ SKJ'6*6
public Page(){ ?d)FYB
4iJ4g% ]
} W 6CNMI]
m"vWu0/#
/** construct the page by everyPage Sp@{5
* @param everyPage @&2#kO~=
* */ y&2O)z!B
public Page(int everyPage){ <X]dR
6FT
this.everyPage = everyPage; N)X51;+
} zmU>
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/** The whole constructor */ 34qfP{9!N
public Page(boolean hasPrePage, boolean hasNextPage, f6%7:B d
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int everyPage, int totalPage, - s0QEQ
int currentPage, int beginIndex){ \PK}4<x}
this.hasPrePage = hasPrePage; n<MreKixE
this.hasNextPage = hasNextPage; n#)kvr
this.everyPage = everyPage; uG4Q\,R
this.totalPage = totalPage; k
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this.currentPage = currentPage; LS4E.Xdn
this.beginIndex = beginIndex; B k~%
} s6_[H
p}h9>R
/** Y !AQ7F
* @return i,y7R?-K
* Returns the beginIndex. A]OVmw
*/ x%,!px3s
publicint getBeginIndex(){ u$mp%d8
return beginIndex; G0v<`/|>}
} ?a` $Y>?h
9d&}CZr
/** A{ a`%FAV
* @param beginIndex Z+C&?K
* The beginIndex to set. nh%Q";
*/ ph=U<D4
publicvoid setBeginIndex(int beginIndex){ 3Uni{Z]Q)
this.beginIndex = beginIndex; C07 U.nzh
} *]* D^'
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/** IP l]$j>N
* @return #nJ&`woZt
* Returns the currentPage. oH kjMqju
*/ [Xo}CU
publicint getCurrentPage(){ 2?\L#=<F
return currentPage; #BX^"J{~
} Fx' E"d
a1#
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/** )>rHM6-W
* @param currentPage glP
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* The currentPage to set. Y!lc/[8
*/ J1{ucFa
publicvoid setCurrentPage(int currentPage){ {A MoE+U
this.currentPage = currentPage; PU^@BZ_m
} y`.m'n7>P
Shb"Jc_i
/** ouR(l;
* @return z7um9g
* Returns the everyPage. -[.A6W
*/ #gY|T|
publicint getEveryPage(){ {aq}Q|?/
return everyPage; uQtwh08i
} 'K|tgsvgme
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/** lT~A~O
* @param everyPage OFcqouGE
* The everyPage to set. *IBCThj
*/ Bwg\_:vq
publicvoid setEveryPage(int everyPage){ [u}2xsSx
this.everyPage = everyPage; zV"oB9\9O
} )NCkq~M
Jsp>v'Qvq
/** Q XV8][
* @return f!aE/e\
* Returns the hasNextPage. a#4 'X*
*/ Vm
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publicboolean getHasNextPage(){ =Frbhh57
return hasNextPage; JypXQC}~
} }g|)+V\A
;IYH5sG{
/** yCOIv!/zy
* @param hasNextPage nH% 1lD?:
* The hasNextPage to set. J=C63YB
*/ 8}(ul
publicvoid setHasNextPage(boolean hasNextPage){ cPm-)/E)i
this.hasNextPage = hasNextPage; A T'P=)F@
} 2>!?EIE7
<UMT:`h1MZ
/** jJDYl( [
* @return &9F(uk=X
* Returns the hasPrePage. j1{\nP/
*/ t=Um@;wh
publicboolean getHasPrePage(){ q=40l
return hasPrePage; lSk<euCYs
} +|=5zWI/
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/** ';0NWFP
* @param hasPrePage _cW6H B^j
* The hasPrePage to set. f8'$Mn,
*/ ,@'M'S
publicvoid setHasPrePage(boolean hasPrePage){ p/f!\
this.hasPrePage = hasPrePage; OnKPD=<
} $=-Q]ld&]
r!7e:p JLO
/** t|Ipxk.)
* @return Returns the totalPage. A->y#KQ
* ^sjL@.'m$N
*/ Y[yw8a
publicint getTotalPage(){ a|v}L,
return totalPage; MN22#G4j^w
} VI(;8
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/** )5Bkm{v3
* @param totalPage Dxwv\+7]
* The totalPage to set. 2%DleR'i
*/ j_r7oARL
publicvoid setTotalPage(int totalPage){ <XHS@|
this.totalPage = totalPage; *I(g~p
} f @cs<x
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} XFg.Z+ #
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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 BU="BB/[
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个PageUtil,负责对Page对象进行构造: v^lR]9;
java代码: QxGQF|
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/*Created on 2005-4-14*/ W].P(A>m
package org.flyware.util.page; QS~;C&1Hl
a*pZcv<
import org.apache.commons.logging.Log; x Qh?
import org.apache.commons.logging.LogFactory; jj)9jUz
LaE;{ jY
/** TgaDzF,j{A
* @author Joa 9@yP;{Q
* -%=StWdb
*/ sK:,c5^
publicclass PageUtil { 4Pljyq:
f/b }X3K
privatestaticfinal Log logger = LogFactory.getLog ;UgRm#
n;"4`6L~
(PageUtil.class); ~^.&nph
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/** lxK_+fj
q
* Use the origin page to create a new page ED/-,>[f
* @param page k~Pm.@,3o
* @param totalRecords F_~-o,\
* @return Q;P ~'
*/ D^PsV
publicstatic Page createPage(Page page, int 9ok|]d P
c
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totalRecords){ Xh]\q)
return createPage(page.getEveryPage(), .;tO;j|6
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page.getCurrentPage(), totalRecords); ^BM/K&7^
} }bznx[4?I
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/** [6S"iNiyKT
* the basic page utils not including exception L1Q QU
Kc udWW]
handler (r[<g*+3
* @param everyPage 8"LaP3U
* @param currentPage z K8#gif@
* @param totalRecords ):78GVp
* @return page M{kPEl&Z
*/ YY!(/<VI
publicstatic Page createPage(int everyPage, int na']{a1K
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currentPage, int totalRecords){ lO $M6l
everyPage = getEveryPage(everyPage); #>'1oC{
currentPage = getCurrentPage(currentPage); ap%o\&T;
int beginIndex = getBeginIndex(everyPage, MF\n@lX
~vl: Tb
currentPage); !v;r3*#Nky
int totalPage = getTotalPage(everyPage, h.=B!wKK
jPU#{Wo#
totalRecords); h/TPd]
boolean hasNextPage = hasNextPage(currentPage, 'fAD Dh}
RO.(k!J .
totalPage); V2FE|+R%g
boolean hasPrePage = hasPrePage(currentPage); qk,cp},2K
<$yer)_J!k
returnnew Page(hasPrePage, hasNextPage, '*,4F'
everyPage, totalPage, _Mt:^H}Sy
currentPage, 8&C(0H]1
<Ab:yD`K!
beginIndex); sId5pY!
} ONjc},_
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privatestaticint getEveryPage(int everyPage){ Y!7P>?)`,X
return everyPage == 0 ? 10 : everyPage; a+~o: 5
} ONGe/CEXT
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privatestaticint getCurrentPage(int currentPage){ qBNiuV;*
return currentPage == 0 ? 1 : currentPage; b<( W}$x
} 2@&|hd=-
QNJG}Upl
privatestaticint getBeginIndex(int everyPage, int S-/#3
sMS`-,37u
currentPage){ ,?d%&3z<a
return(currentPage - 1) * everyPage; JZXc1R| 9
} ?0(B;[xEJ
B7 PmG
f)b
privatestaticint getTotalPage(int everyPage, int ~Op1NE
<M7*N.
totalRecords){ )mPlB.
int totalPage = 0; @
tIB'|O
4r. W:}4:
if(totalRecords % everyPage == 0) a+/|O*>#
totalPage = totalRecords / everyPage; doc
else 6EU4
totalPage = totalRecords / everyPage + 1 ; r(i)9RI+(
^I{]Um:
return totalPage; {_Qxe1^g
} :*@|"4
ikhX5
&e
privatestaticboolean hasPrePage(int currentPage){ 5S]P#8
return currentPage == 1 ? false : true; X=pt}j,QrP
} <S$21NtM87
udGGDH
privatestaticboolean hasNextPage(int currentPage, 5{q/z^]
_)E8XyzF
int totalPage){ ennz/'
return currentPage == totalPage || totalPage == PAwg&._K
*'YNRM\}
0 ? false : true;
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ON
} %GbPrlu
!>y}Xq{bm3
gVU\^KN]
} )95yV;n
3c ^=<i
%
H}V*<mgw
y] ]Vp~R:[
8.Ef 5-m
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }8M`2HMFR
pE/3-0;}N
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 hav?mnVJ
7(8
做法如下:
Jf<yTAm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 tc<M]4-
yr9A0F0
的信息,和一个结果集List: s<_LcQbt{
java代码: pt%~,M _
SE9u2Jk
jjwMvf.R
/*Created on 2005-6-13*/ %[\x%m)
package com.adt.bo; d)1sP0Z_@
vDeG20.?Z
import java.util.List; `V):V4!j),
*DCNu{6
import org.flyware.util.page.Page; &iiK ZZ`_o
oB06{/6
/** |z|)r"*\4
* @author Joa _2X6bIE
*/ %r
publicclass Result { AzO3 (1:
Na 9l#
private Page page; VWA -?%r
Pv %vx U
private List content; yCkW2p]s,K
*o e0=
/** &Wv`AoV
* The default constructor fFZ`rPb
*/ F `pyhc>1;
public Result(){ S,Wl)\
super(); K~y9zF{
} E0)mI)RW.
_/%]:
/** O{ %A&Ui
* The constructor using fields u5XU`!
* Q$.V:#
* @param page J'&B:PZObB
* @param content FM"GK '
*/ %YvSHh;c
public Result(Page page, List content){ A.$VM#
this.page = page; j^$3vj5E[
this.content = content; d%_78nOh"
} $~G0#JL
}OP%p/eY
/** }lC64;yo
* @return Returns the content. \p3nd!OIG
*/ 'x45E.wYw
publicList getContent(){ yNqm]H3<MP
return content; LN~N
Fjs
} Jp.3KA>
}W@#S_-e8
/** #zSi/r/=1
* @return Returns the page. K.#,O+-Kg`
*/ `hK>bHj
public Page getPage(){ {?
K|(C
return page; mHI4wS>()+
} zqvRkMWc M
,Y g5X
/** i^yH?bH @~
* @param content l?@MUsg+
* The content to set. `b^#quz
*/ gc,J2B]61
public void setContent(List content){ EvSnZB1 y
this.content = content; `uNvFlP
} yd0=h7s
5I)~4.U|,m
/** EDq$vB
* @param page AT%*
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* The page to set. \'s$ZN$k
*/ @Hspg^
publicvoid setPage(Page page){ 8u:v:>D.'
this.page = page; y(/jTS/hd
} kwDh|K
} 'B:Z=0{>N
;B|^2i1Wi
u@=+#q~/P
8m/FKO (r
o;M.Rt\A
2. 编写业务逻辑接口,并实现它(UserManager, B91S
h`
}J+ce
UserManagerImpl) xUiWiOihr6
java代码: #sz]PZ\
pW*{Mx
B^8ZoF
/*Created on 2005-7-15*/ p|FlWR'mA
package com.adt.service; A6?qIy
L~*|,h
import net.sf.hibernate.HibernateException; #;\L,a|>*
msA' 5>
import org.flyware.util.page.Page; 'L>&ZgLy
`DgaO-Dg3
import com.adt.bo.Result; SWNU1x{,c\
'h!h!
/** fnLR
* @author Joa ;=5@h!@R
*/ f
pv= P
publicinterface UserManager { XysFwi
YXczyZA`x
public Result listUser(Page page)throws ;,v!7
! 6p>P4TT
HibernateException; 2x7(}+eD
tx^92R2/
} V+qFT3?-
);Tx5Z}
|Hx%f
~/^y.SsWM
a(PjcQ4dY
java代码: VKq0<+M
^-gfib|VGe
fp.!VOy
/*Created on 2005-7-15*/ U>/<6Wd
package com.adt.service.impl; gbY LA a
ry$tK"v/
import java.util.List; @PYW|*VS
[GtcaX{Zz
import net.sf.hibernate.HibernateException; #^5a\XJb
5Z*
b(R
import org.flyware.util.page.Page; >}-~rZ
import org.flyware.util.page.PageUtil; 4fu'QZ(}
gJ]Cq/gC
import com.adt.bo.Result; yr
FZ~r@-
import com.adt.dao.UserDAO; Oamv9RyDvC
import com.adt.exception.ObjectNotFoundException; pwa.q
import com.adt.service.UserManager; E"Zb};}
M%7`8KQ
/** t{+M|Y
* @author Joa +n@f'a">
*/ /uK)rG
F
publicclass UserManagerImpl implements UserManager { q $t&|{
^$e0t;W=
private UserDAO userDAO; +2-
qlU
4O$ mR
/** 1v;'d1Hg;
* @param userDAO The userDAO to set. J2rvJ2l=t
*/ \M+MDT&
publicvoid setUserDAO(UserDAO userDAO){ ^Y$QR]
this.userDAO = userDAO; {d| |q<.-
} 7@FDBjq
ZH\0=l)
/* (non-Javadoc) V{43HA10b
* @see com.adt.service.UserManager#listUser g+e:@@ug
9X!ET!
(org.flyware.util.page.Page) I%SuT7"Do
*/ E3y6c)<
public Result listUser(Page page)throws 3voW
Ud$Q0m&
HibernateException, ObjectNotFoundException { :lNg:r$4
int totalRecords = userDAO.getUserCount(); 9H>BWjS
if(totalRecords == 0) o1e4.-xI
throw new ObjectNotFoundException GaHA%
I=U+GY:
("userNotExist"); 3Hs$]nQ_X
page = PageUtil.createPage(page, totalRecords); 9t#P~>:jY}
List users = userDAO.getUserByPage(page); R_7
6W&
returnnew Result(page, users); mU>&ql?e
} ~
W@X-
ooY\t +
} J`W-]3S#
~xw5\Y^
\N? 7WQ
Yhe+u\vGs\
%Mh Q
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 6nc0=~='$
n"iNKR>nW
询,接下来编写UserDAO的代码:
NaF(\j
3. UserDAO 和 UserDAOImpl: {H+?z<BF<
java代码: m#*h{U$
wEE2a56L-
i =-8@
/*Created on 2005-7-15*/ NIaF 5z
package com.adt.dao; =rEA:Q`~w
7RD$=?o O'
import java.util.List; wrabyRjK
`os8;`G
import org.flyware.util.page.Page; $6#
lTYN~
o*-9J2V=J
import net.sf.hibernate.HibernateException; %MbyKz:X
F;pQ \Y
/** Q70bEHLA
* @author Joa U-eI\Lu
*/ VRtO; F
publicinterface UserDAO extends BaseDAO { tfA}`*$s
{\EOo-&A
publicList getUserByName(String name)throws p0Gk j-
ck$M(^)l
HibernateException; U;pe:
srK53vKMHW
publicint getUserCount()throws HibernateException; ljVIE/iq
rGQ5l1</
publicList getUserByPage(Page page)throws 5}XvL'
781]THY=
HibernateException; 3{e'YD~hP
T9?54r
} w4,]2Ccn.
2d 8=h6
4jGLAor|
DvYwCgLR
RLHYw@-j@
java代码: =Dk7RKoHF
B?3juyB`--
@1g&Z}L
o
/*Created on 2005-7-15*/ /zT`Y=1
package com.adt.dao.impl; 0%
+'
LG&5VxT=,<
import java.util.List; .YR8v1Cp
a+Ab]m8`
import org.flyware.util.page.Page; 2+:'0Krc
C
) ?uE'
import net.sf.hibernate.HibernateException; Q'K$L9q
import net.sf.hibernate.Query; 7$7n71o
+s~.A_7)
import com.adt.dao.UserDAO; ^A!$i$NON
=9$mbn
r
/** O%g\B8;
* @author Joa S-!=NX&C
*/ CGZ^hoh/
public class UserDAOImpl extends BaseDAOHibernateImpl >DP:GcTG
Fw"$A0
implements UserDAO { D:JS)+]
4pPI'd&/7
/* (non-Javadoc) d!V$Y}n
* @see com.adt.dao.UserDAO#getUserByName K5`Rk"s
P1V1as
(java.lang.String) 9$RIH\*
*/ }C,O
publicList getUserByName(String name)throws P^i.La,
H;S%Y`V
HibernateException { 2|{V,!/cvG
String querySentence = "FROM user in class ipjkZG@
X+l'bp]Ry
com.adt.po.User WHERE user.name=:name"; ;`UecLb#
Query query = getSession().createQuery tsv$ r$Se
|[1D$Qv
(querySentence); Lh ap4:
query.setParameter("name", name); JE;+T[I
return query.list(); f*fE};
} Ik~1:D]f
B42sb_
/* (non-Javadoc) 'jjb[{g^}}
* @see com.adt.dao.UserDAO#getUserCount() ][7p+IsB
*/ >]?H`>4(
publicint getUserCount()throws HibernateException { =k{`oO~:9+
int count = 0; BX< dSK
String querySentence = "SELECT count(*) FROM =SBBvnPLI
yI)~]K
r
user in class com.adt.po.User"; >NM\TLET~
Query query = getSession().createQuery *>."V5{;S
y%cO#P@
(querySentence); YnTB&GPxl
count = ((Integer)query.iterate().next 1-VT}J(
I1"MPx{
()).intValue(); >M;u*Go`QO
return count; ^p=L\SJ
} uf' 4'
8;" *6vHZ
/* (non-Javadoc) jH*)%n5,\
* @see com.adt.dao.UserDAO#getUserByPage Qa`hR
XDz5b.,
(org.flyware.util.page.Page) =?
:@
*/ B0Xl+JIR#
publicList getUserByPage(Page page)throws ;*cLG#&'M
%2l7Hmp4H
HibernateException { ^g>1U5c
String querySentence = "FROM user in class !GK$[9
:`Az/U[
com.adt.po.User"; 5VE2@Fn}
Query query = getSession().createQuery K_/B?h
"!UVs+)]
(querySentence); P?ep]
query.setFirstResult(page.getBeginIndex()) eon!CE0
.setMaxResults(page.getEveryPage()); "Ty/k8?
return query.list(); buMqF-j
} C"w
{\
&R
L;6.r3bL
} m7qqY
l!~
mxUb
\nvAa_,
b1`r!B,
5OP`c<
至此,一个完整的分页程序完成。前台的只需要调用 >G"X J<IO
#-#NqX:
userManager.listUser(page)即可得到一个Page对象和结果集对象 x"4%(xBu
/VTM 9)u
的综合体,而传入的参数page对象则可以由前台传入,如果用 8v92Ng7
[rYT
webwork,甚至可以直接在配置文件中指定。 v3RcwySk
2#5,MP~r
下面给出一个webwork调用示例: LMl~yqM
java代码: n!ok?=(kQ
9'~-U
/Z%>ArAx
/*Created on 2005-6-17*/
_^t-9
package com.adt.action.user; u<tk G B
) g1a'G
import java.util.List; b"j|Bb
@,H9zrjVFZ
import org.apache.commons.logging.Log; w~\%vXla
import org.apache.commons.logging.LogFactory; 4FMF|U
import org.flyware.util.page.Page; WE!vSZ3R
z(HaRB3l
import com.adt.bo.Result; "HIXm
import com.adt.service.UserService; tiaR4PB
import com.opensymphony.xwork.Action; -8Ti*:
2XSHZ|;
/** 9s$U%F6}
* @author Joa uOi&G:=
*/ }iN2KeLAF
publicclass ListUser implementsAction{ "4xfrlOc
z01>'
privatestaticfinal Log logger = LogFactory.getLog NeOxpn[
"5|Lz) =
(ListUser.class); i76 Yo5
VM=+afY5M
private UserService userService; c|~6Ie
U bz"rCjq
private Page page; P&A|PY,P
$&P?l=UG
privateList users; MBr:?PE7
\c`oy=qY0
/* :osz
* (non-Javadoc) ?/#}ZZK^
* o>D
* @see com.opensymphony.xwork.Action#execute() BN_7Ay/k
*/ mj,fp2D;%
publicString execute()throwsException{ l5t2\Fl
Result result = userService.listUser(page); dKhA$f~
page = result.getPage(); YE+$H%Jl!
users = result.getContent(); Xh+ia#K
return SUCCESS; hsLzj\)6
} A7XnHPIw
s4= "kT]
/** t,%iL
* @return Returns the page. $a;]_ Y
*/ 9l/EjF^
public Page getPage(){ "E=j|q
return page; t2{~bzq1X
} |1=
!;.#
6)gd^{
/** u62 )QJE
* @return Returns the users. e&It
*/ JN3cg
publicList getUsers(){ (zo^Nn9VJ
return users; @$@mqHI}
} |I8Mk.Z=FA
"E!mva*NU
/** V1=*z
* @param page }qPhx6nP
* The page to set. wzcai
0y*
*/ wOgE|n
publicvoid setPage(Page page){ LX+5|u
this.page = page; B\`Aojw"E?
} /!FWuRe^
")#<y@Rv
/**
0au)g!ti
* @param users y7u^zH6wj
* The users to set. 8|1^|B(l
*/ YrI|gz)
publicvoid setUsers(List users){ *6ZCDm&N
this.users = users; Y#V8(DTyH
} A]`:VC=IU
g;p)n
/** =odkz}bU
* @param userService H.
,;-
* The userService to set. PK6iY7Qp)
*/ |!z2oO
publicvoid setUserService(UserService userService){ Q'NmSX)0
this.userService = userService; Z)<
wv&K
} n[+'OU[
} ?2J?XS>
6o&ZIY