Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Tg-HR8}X
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ia'm9Z*
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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 `;R
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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 8#_"WzDw
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分页支持类: h88IP:bo
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java代码: f'-)
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package com.javaeye.common.util; Qt
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import java.util.List; 6tDCaB
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publicclass PaginationSupport { pRTdP/(OQ
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publicfinalstaticint PAGESIZE = 30; xtN=?WjVe0
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privateint pageSize = PAGESIZE; B+pJWl8u
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privateList items; D,<#pNO_
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privateint totalCount; efnj5|JSV
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privateint[] indexes = newint[0]; !J%m 7A
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privateint startIndex = 0; .o_?n.H'&
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public PaginationSupport(List items, int "?Mf%u1R
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totalCount){ D,)^l@UP
setPageSize(PAGESIZE); I,Z'ed..
setTotalCount(totalCount); `JrvD
setItems(items); MV,;l94?%=
setStartIndex(0); 8>(DQ"h
} OD~TWT_
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public PaginationSupport(List items, int `
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totalCount, int startIndex){ zr1,A#BV
setPageSize(PAGESIZE); uV'w0`$y
setTotalCount(totalCount); <Ky6|&!
setItems(items); J@4,@+X
setStartIndex(startIndex); HbUadPr
} $S(q;Y
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public PaginationSupport(List items, int (!iGQj(m
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totalCount, int pageSize, int startIndex){ p#T^o]+
setPageSize(pageSize); "v9i;Ba>+
setTotalCount(totalCount); YJ[Jo3M@j0
setItems(items); c~=yD:$
setStartIndex(startIndex); 0s%rd>3
} } F; Nh7?
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publicList getItems(){ S}T*g UO
return items; OlJkyL8|
} zV<vwIUrr
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publicvoid setItems(List items){ LmA I vEr
this.items = items; 1X45~
} MGGc
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publicint getPageSize(){ ::Nhs/B/
return pageSize; Jjgy;*hM
} EgY yvS)
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publicvoid setPageSize(int pageSize){ ;&9A
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this.pageSize = pageSize; ,aLdW,<6
} )ZP-t!).G#
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publicint getTotalCount(){ _H(:$=$Q
return totalCount; @jp}WwC/
} eK]$8l|LI
IUJRP
publicvoid setTotalCount(int totalCount){ fsxZQ=-PW
if(totalCount > 0){ bR*/d-v^
this.totalCount = totalCount;
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int count = totalCount / nYv`{0S+m
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pageSize; \;%DDw
if(totalCount % pageSize > 0) UFED*al#
count++; V`7^v:
indexes = newint[count]; !_|rVg.
for(int i = 0; i < count; i++){ k\J 6WT
indexes = pageSize * 9j6
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i; @A-^~LoP.
} p7YfOUo
k
}else{ 51\N+
this.totalCount = 0; ]("5O V5
} wv ~?<DF
} I}@m6D|\
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publicint[] getIndexes(){ M-B -
return indexes; Yiq8>|
} s=uWBh3J
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; yM8<)6=
} J3$Ce%<
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publicint getStartIndex(){ &>Ko}?w
return startIndex; J6)&b7
} =:!$'q:
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publicvoid setStartIndex(int startIndex){ PI~W6a7p
if(totalCount <= 0) SuHv{u45
this.startIndex = 0; ppBIl6
elseif(startIndex >= totalCount) P 3CzX48^
this.startIndex = indexes $)5-}NJf'
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[indexes.length - 1]; zJp@\Yo+
elseif(startIndex < 0) A|D]e)/6+B
this.startIndex = 0; \*_@`1m
else{ _v+mjDdQ
this.startIndex = indexes .skR4f,h
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[startIndex / pageSize]; t!g9,xG<X
} Px>Gc:!>
} nn"Wn2ciS
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publicint getNextIndex(){ Y\qiYra
int nextIndex = getStartIndex() + *$KUnd-T
4rh*&'
pageSize; v GF<
if(nextIndex >= totalCount) ~[mAv#d&i
return getStartIndex(); &dino
else :LuzKCvBP
return nextIndex; Pw"o[8
} O@
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publicint getPreviousIndex(){ Au6*hv3:
int previousIndex = getStartIndex() - 4[ S0~O{r
g 36\%L
pageSize; vlD!YNy
if(previousIndex < 0) 9 pGND]tIi
return0; 2ja@NT
else M=!RJ%6f
return previousIndex; u7e g:0Y
} e*Gm()Vu,
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} (X
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抽象业务类 l
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java代码: pLFJ"3IJB
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/** [3s p
* Created on 2005-7-12 vu%:0p`K
*/ Uf`lGGM
package com.javaeye.common.business; *|f&a
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import java.io.Serializable; ERW>G{+
import java.util.List; 93Yo}6>
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import org.hibernate.Criteria; [I;5V= bKW
import org.hibernate.HibernateException; 1GnT^u y/
import org.hibernate.Session; H(^O{JC]y!
import org.hibernate.criterion.DetachedCriteria; gDw:Z/1X`
import org.hibernate.criterion.Projections; OAc*W<Q0
import 1$q>\
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org.springframework.orm.hibernate3.HibernateCallback; VK*2`Z1
import H:X=v+W
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org.springframework.orm.hibernate3.support.HibernateDaoS U8Pnt|0 M
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upport; TU&t 1_6
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import com.javaeye.common.util.PaginationSupport; ^KU:5Bn
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public abstract class AbstractManager extends >-Qg4%m
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HibernateDaoSupport { rAdYBr=0
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privateboolean cacheQueries = false; \8uPHf_
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privateString queryCacheRegion; <ByR!Y
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publicvoid setCacheQueries(boolean t5z6{`
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cacheQueries){ y)W.xR
this.cacheQueries = cacheQueries; Ge+&C RhyX
} ZDZPJp,
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publicvoid setQueryCacheRegion(String -R,[/7zj
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queryCacheRegion){ OCzWP,
this.queryCacheRegion = V|> u,
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queryCacheRegion; &z-f,`yG
} }b+tD3+
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publicvoid save(finalObject entity){ v/]Bo[a
getHibernateTemplate().save(entity); rl^_RI
} XelY?Ph,,
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publicvoid persist(finalObject entity){ [=Wn7cr
getHibernateTemplate().save(entity); p6(n\eg R
} % Ke:%##Y
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publicvoid update(finalObject entity){ pa&*n=&cL
getHibernateTemplate().update(entity); |X9YVZC
} B.&ly/d
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publicvoid delete(finalObject entity){ ]6{G;f$
getHibernateTemplate().delete(entity); pR8]HNY0
} tw8@&8"
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publicObject load(finalClass entity, t_&FK A
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finalSerializable id){ NYD#I{h
return getHibernateTemplate().load dL<okw
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(entity, id); 0@E[IDmp
}
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publicObject get(finalClass entity, &yzC\XdA
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finalSerializable id){ 0fnd9`N!0
return getHibernateTemplate().get VAc-RaA
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(entity, id); KcVCA
} z2og&|uT
i% k`/X;
publicList findAll(finalClass entity){ 3|RfX
return getHibernateTemplate().find("from i/*&;
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" + entity.getName()); /ocdAW`0
} wo84V!"A
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publicList findByNamedQuery(finalString cS,(HLO91
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namedQuery){ E0}`+x
return getHibernateTemplate dc_^
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().findByNamedQuery(namedQuery); $k*E^~qT
} !1!;}uzt
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publicList findByNamedQuery(finalString query, >+R`3|o
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finalObject parameter){ |~k=:sSz{
return getHibernateTemplate ^V v7u@y
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().findByNamedQuery(query, parameter); }S3m
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} u&".kk
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publicList findByNamedQuery(finalString query, e{.2*>pH
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finalObject[] parameters){ B+eB=KL
return getHibernateTemplate cnC&=6=a<
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().findByNamedQuery(query, parameters); tTe\#o`
} ry3;60E\)
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publicList find(finalString query){ Lo @mQ
return getHibernateTemplate().find ,*a8]L
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(query); =:v\}/
} @~'c(+<3
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publicList find(finalString query, finalObject oHB51< }
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parameter){ IfeG"ua|
return getHibernateTemplate().find =G;whd}]
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(query, parameter); cG6Q$
} -o6K_R}R
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public PaginationSupport findPageByCriteria z<ptrH
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(final DetachedCriteria detachedCriteria){ tx}{E<\>$
return findPageByCriteria k4'rDJfB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); nYY@+%`]z
} 0^*4LM|z
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public PaginationSupport findPageByCriteria O1Ey{2Q
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(final DetachedCriteria detachedCriteria, finalint $d{{><
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startIndex){ *I(>[m!
return findPageByCriteria [m?eSq6e2b
<`9Q{~*=t
(detachedCriteria, PaginationSupport.PAGESIZE, 4(& W>E
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startIndex); uNxR#S
} 2Y\,[ $z
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public PaginationSupport findPageByCriteria ` fu(
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(final DetachedCriteria detachedCriteria, finalint Pan^@B=Q
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pageSize, d2'9C6t
finalint startIndex){ F/tBr%RV
return(PaginationSupport) *$Aneq0f
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getHibernateTemplate().execute(new HibernateCallback(){ vY7C!O/y_k
publicObject doInHibernate ah>;wW!6/
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(Session session)throws HibernateException { xqmP/1=NO
Criteria criteria = 3:&!Q*i;
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detachedCriteria.getExecutableCriteria(session); MIub^ $<C
int totalCount = CtTG`)"|
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((Integer) criteria.setProjection(Projections.rowCount ?=dyU(
xop9*Z$
()).uniqueResult()).intValue(); q{n~v>wU
criteria.setProjection 8b8ui
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(null); O _yJR
List items = <:-|>R".
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criteria.setFirstResult(startIndex).setMaxResults W#$ pt>h)
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(pageSize).list(); "G)-:!H
PaginationSupport ps = x|<rt966A
d!{,[8&
new PaginationSupport(items, totalCount, pageSize, 5u'"m<4
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startIndex); B'"C?d<7
return ps; *>n<7T0
} /k|y \'<
}, true); X3tpW`alo
} DPw"UY:
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public List findAllByCriteria(final rBye%rQRq
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DetachedCriteria detachedCriteria){ !R-M:|
return(List) getHibernateTemplate @\e2Q&O
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().execute(new HibernateCallback(){ "1$OPt5
publicObject doInHibernate P6&@fwJ<
&s->,-,
(Session session)throws HibernateException { oJK1~;:
Criteria criteria = hn{]Q@(I
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detachedCriteria.getExecutableCriteria(session); 1q0DOf]!T
return criteria.list(); @G+Hrd6
} [wWip1OR
}, true); 2>Hl=bX
} .xS3,O_[
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public int getCountByCriteria(final J3KY?,g3O_
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DetachedCriteria detachedCriteria){ 7(rNJPrU~=
Integer count = (Integer) D^yZ!}Kl
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getHibernateTemplate().execute(new HibernateCallback(){ X<dQq`kZ
publicObject doInHibernate VC5LxA0{
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(Session session)throws HibernateException { hNgbHzW
Criteria criteria = 6My=GByC
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detachedCriteria.getExecutableCriteria(session); (JHzwI8+
return c ]M!4.
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criteria.setProjection(Projections.rowCount W+36"?*k3
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()).uniqueResult(); 2eo]D?}
} 4Xt.}S!
}, true); (jd)sf6Tj[
return count.intValue(); 1"?3l`i
} &6<>hqR^
} K>iM6Uv
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用户在web层构造查询条件detachedCriteria,和可选的 {`?C5<r
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 XgL-t~_
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PaginationSupport的实例ps。 ,{==f7|w
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ps.getItems()得到已分页好的结果集 Afa|6zZ>
ps.getIndexes()得到分页索引的数组 2L"$p?
ps.getTotalCount()得到总结果数 lz=$Dz
ps.getStartIndex()当前分页索引 LA &W@
ps.getNextIndex()下一页索引 \) DJo
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zURxXo/\V
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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 _+Tq&,_:o
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一下代码重构了。 S}L$-7Ct
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我把原本我的做法也提供出来供大家讨论吧: S:!gj2q9|
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首先,为了实现分页查询,我封装了一个Page类: yQ$Q{,S9
java代码: C>l{_J)n
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/*Created on 2005-4-14*/ {2jetX`@h
package org.flyware.util.page; ]`@= ;w
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/** `y"(\1
* @author Joa JF{yhx,+p
* %#5\^4$z|N
*/ "rxhS;
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publicclass Page { ^n! j"
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/** imply if the page has previous page */ i/Zv@GF
privateboolean hasPrePage; ,Sz`$'^c
x<&2`=
/** imply if the page has next page */ $H\[yg>4
privateboolean hasNextPage; t2bv
nh
etnq{tE5
/** the number of every page */ 8&[Lr o9
privateint everyPage; U&F1}P$fb
7Iz%Jty
/** the total page number */ hM_0/o-
privateint totalPage; 6yn34'yw
F7f psAt7
/** the number of current page */ >z{*>i,m1
privateint currentPage; =7^rKrD
+\Hh|Uz5
/** the begin index of the records by the current a7$]"
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query */ 'gBGZ?^N!U
privateint beginIndex; [w*t(A
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/** The default constructor */ =1|^) 4M,x
public Page(){ V(gmC%6%l*
qu8!fFQjYL
} R_DstpsT
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/** construct the page by everyPage \@\r`=WgB
* @param everyPage ajM3Uwnr
* */ a:q>7V|%$
public Page(int everyPage){ z (1zth
this.everyPage = everyPage; dM-qd`
} egXHp<bqw
`EBI$;!
/** The whole constructor */ %-nYK3
public Page(boolean hasPrePage, boolean hasNextPage, 5{z muv:
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int everyPage, int totalPage, A{Kc"s4fO
int currentPage, int beginIndex){ %yyvB5Y^
this.hasPrePage = hasPrePage; s0zN#'o]
this.hasNextPage = hasNextPage; Jn|sS(Q}
this.everyPage = everyPage; Ux/|D_rlf
this.totalPage = totalPage; eq"
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this.currentPage = currentPage; .8GX8[t
this.beginIndex = beginIndex; CI#6r8u
} mBwM=LAZ
w$)NW57[|
/** B0M(&)!%
* @return S|jE1v"L
* Returns the beginIndex. `i2:@?Kl9
*/ VxP cC+
publicint getBeginIndex(){ cko^_V&x
return beginIndex; ShIJ6LZ
} ]Pp}=hcD
a 23XrX
/** hl/) 1sOIR
* @param beginIndex '+s ?\X4VC
* The beginIndex to set. +QW|8b
*/ ez-jVi-Fi
publicvoid setBeginIndex(int beginIndex){ {i^F4A@=Z
this.beginIndex = beginIndex; hNRN`\5Z
} -u$U~?|`
f=EWr8mno
/** +^ cjdH*
* @return gTQc=,3l3
* Returns the currentPage. FX
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*/ h}U>K4BJ
publicint getCurrentPage(){ B'v~0Kau
return currentPage; fq[1 |Q
} Y6[O
s1
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/** nZX`y
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* @param currentPage 96d&vm~m1
* The currentPage to set. 3+/^
*/ ;)ku SH
publicvoid setCurrentPage(int currentPage){ ;L@p|]fu
this.currentPage = currentPage; 20
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} i*)BFV_-
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/** tc|PN+v;
* @return CklIrD{
* Returns the everyPage. d6f T
*/ UlMc8 z
publicint getEveryPage(){ .O&[9`"'
return everyPage; xdgbs-a)
} '!"rE1e
2w;Cw~<=d
/** H1d2WNr[
* @param everyPage s>I~%+V.?:
* The everyPage to set. W) ?s''WE;
*/ F|&%Z(@a
publicvoid setEveryPage(int everyPage){ 4d8}g25C
this.everyPage = everyPage; +&4@HHU{G
} &U_T1-UR2
iLO,XW?d
v
/** o&)v{q
* @return '[vCC'
* Returns the hasNextPage. ~[Z(6yX
*/ "uP~hFA7M
publicboolean getHasNextPage(){ JYR^k=
return hasNextPage; lxfv'A
} ?BRZ){)
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/** C'6c,
* @param hasNextPage e8 c.&j3m
* The hasNextPage to set. bHg 0,N
*/ %F87"v~
publicvoid setHasNextPage(boolean hasNextPage){ ;qs^+
this.hasNextPage = hasNextPage; i
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} 6~O;t'd
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/** -U{!'e8YiN
* @return qGi\*sc>x
* Returns the hasPrePage. e8&7W3 m
*/ (_R!:H(]m
publicboolean getHasPrePage(){ EY@KWs3"H
return hasPrePage; sWKv>bx
} ;;N#'.xD
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/** 5&_R+g
* @param hasPrePage t!59upbN}3
* The hasPrePage to set. Rl'xEtaN
*/ *i"Mu00b
publicvoid setHasPrePage(boolean hasPrePage){ +I@2,T(eG
this.hasPrePage = hasPrePage; cR/e
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} hyY^$p+
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/** A:\_ \B%<
* @return Returns the totalPage. H'I5LYsXO~
* }tJMnq/m($
*/ jX,A.
publicint getTotalPage(){ `(]mUW
return totalPage; +&*>FeJY
} iZ0.rcQj'o
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/** )>]SJQ!k
* @param totalPage &{8[I3#@
* The totalPage to set. F#o{/u?T
*/ +B7UGI
publicvoid setTotalPage(int totalPage){ _+gpdQq\p
this.totalPage = totalPage; V/ZWyYxjLi
} qz 29f
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} }dSFv
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ktv{-WG2_
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 ve4QS P
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个PageUtil,负责对Page对象进行构造: Lya?b
java代码: 5d|+ c<
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/*Created on 2005-4-14*/ }80n5X<9
package org.flyware.util.page; XB%`5wwd
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import org.apache.commons.logging.Log; u[!Ex=9W
import org.apache.commons.logging.LogFactory; =PoPp
.|K\1qGW0
/** uMBb=
* @author Joa *1}vn%wvn
* _"'-fl98*
*/ H/ub=,Ej*
publicclass PageUtil { (7v`5|'0
^9kdd[
privatestaticfinal Log logger = LogFactory.getLog t*Wxvoxk
gOk^("@
(PageUtil.class); F,XJGD*
9a.[>4}
/** td+[Na0d
* Use the origin page to create a new page Rh7=,=u
* @param page taOsC!Bp
* @param totalRecords ,I[A~
* @return 8\Eq(o}7
*/ =`%%*
publicstatic Page createPage(Page page, int {XYf"ONi
$Vm J[EF1
totalRecords){ !?)iP
return createPage(page.getEveryPage(), W/;qMP1"-
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page.getCurrentPage(), totalRecords); W&^2Fb
} M~!LjJg;
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/** m<22E0=g
* the basic page utils not including exception 1'* {VmM
Xgm9>/y
handler ;:gx;'dm5
* @param everyPage Eb9M;u
* @param currentPage P^*gk P
* @param totalRecords mH3{<^Z6
* @return page >JhIRf
*/ d>7bwG+k
publicstatic Page createPage(int everyPage, int g:c
@
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currentPage, int totalRecords){ hO:X\:G
everyPage = getEveryPage(everyPage); e 3>k"
currentPage = getCurrentPage(currentPage); YuDNm}r[
int beginIndex = getBeginIndex(everyPage, zphStiwIQ
~9ILN~91
currentPage); v6?<)M%
int totalPage = getTotalPage(everyPage, ,K[B/tD{j
}~5xlg$B<<
totalRecords); Jh:-<xy)
boolean hasNextPage = hasNextPage(currentPage, E0S[TEDa]
sw &sF
totalPage); R:JS)>B
boolean hasPrePage = hasPrePage(currentPage);
( ]o6Pi
iJE|u
returnnew Page(hasPrePage, hasNextPage, I!Za2?
everyPage, totalPage, `P4qEsZE>`
currentPage, gf2w@CVF>=
f:g<Bz=u)*
beginIndex); Qs{Qg<}
} ]R{=|
2=NYBOE
privatestaticint getEveryPage(int everyPage){ f1>^kl3@P
return everyPage == 0 ? 10 : everyPage; XsHl%o8,z
} HIeMV,.QN
}Mo9r4}
privatestaticint getCurrentPage(int currentPage){ 9Au+mIN
return currentPage == 0 ? 1 : currentPage; i]LK,'
} \9k{"4jX\
Xl*-A|:j
privatestaticint getBeginIndex(int everyPage, int :<IW'
ikRIL2Y
currentPage){ |,&!Q$<un
return(currentPage - 1) * everyPage; 7\U1K^q
} /ADxHw`k
IJXH_H_%*
privatestaticint getTotalPage(int everyPage, int LDvF)Eg
=-pss 47
totalRecords){ JnY3]
int totalPage = 0; 90aPIs-
1,`x1dcO!A
if(totalRecords % everyPage == 0) %dT%r=%Y
totalPage = totalRecords / everyPage; j)IK
else n7q-)Dv_U
totalPage = totalRecords / everyPage + 1 ; IL:"]`f*
Ef `LBAfOO
return totalPage; $'FPst8Q<
} 6l
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#-HN[U?Gs
privatestaticboolean hasPrePage(int currentPage){ =\%>O7c,8Y
return currentPage == 1 ? false : true; lE|T'?/
} c8"I]Qc7
)Y&De)=
privatestaticboolean hasNextPage(int currentPage, EJtU(HmW
Z#MODf0H@
int totalPage){ 'HcDl@E
return currentPage == totalPage || totalPage == ^]R0d3?>\
Eq<#pX6
0 ? false : true; 56_KB.Ww~
} Yg]f2ke
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/l$noaskX
} WNYLQ=;
}C&c=3V
8rpN2M3h
l*m|b""].u
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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。 49zp@a
}\*Sf[EMD
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 dw4)4_
+tN-X'u##
做法如下: ,6buo~?W:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 gq@."wHU
N8{>M,
的信息,和一个结果集List: \4p<;$'
java代码: G\NCEE'A
+Ae.>%}
>SGSn/AJi
/*Created on 2005-6-13*/ y14@9<~9
package com.adt.bo; pq&c]8H
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import java.util.List; t2SZ]|C
vZDQ@\HrC
import org.flyware.util.page.Page; ,`7GI*Vq
Cp* n2
/** 5k(#kyP
* @author Joa 68!fcK
*/ vxt^rBA
publicclass Result { ,RHHNTB("
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private Page page; v:0i5h&M
]1[;A$7
private List content; g:clSN,
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/** gPi_+-@
* The default constructor }Tef;8d
*/ Mvh_>-i
public Result(){ #"M Pe4
super(); *j*
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} fytx({I
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/** D/Wuan?yPN
* The constructor using fields z,7^dlT
* o%5bg(
* @param page uSQ*/h-<)0
* @param content s?E: ]
*/ X m3t
xp#
public Result(Page page, List content){ mC7Y *
this.page = page; Wd}mC<rv1
this.content = content; )pLq^j
} >`uS NY"tO
W Q&<QVK
/** $S}x'F!4_
* @return Returns the content. ZkJM?Fzq
*/ D.6dPzu`
publicList getContent(){ xVyUUzXs
return content; p o`$^TB^+
} lBdF9F<
.'1j5Y-l`N
/** z Y|g#V-
* @return Returns the page. "p{'984r<
*/ K?je(t^
public Page getPage(){ 9wAc&nl-Y
return page; \PONaRK|[z
} $(R)
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/** kI'A`
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* @param content `[\phv
* The content to set. ^-!HbbVv
*/ [VW;L l
public void setContent(List content){ h;KK6*Z*$E
this.content = content; z{d5Lrk
} ,no:6
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/** J":9
* @param page @;}H<&"
* The page to set. }$1;<
*/ Ag6
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publicvoid setPage(Page page){ 0Y2^}u@5
this.page = page; [BBKj)IK
} 7]j-zv
} )''wu\7A)'
%6'D!H?d
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u&XkbPZ%4c
HJR<d&l;p
2. 编写业务逻辑接口,并实现它(UserManager, zYdtQjv
i@Zj7#e*
UserManagerImpl) e}[we:
java代码: }YP7x|
L"I] mQvd
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/*Created on 2005-7-15*/ Xh"iP %
package com.adt.service; n;-r
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import net.sf.hibernate.HibernateException; +[/r^C
gj,J3x4TK/
import org.flyware.util.page.Page; y
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ue"?S6
import com.adt.bo.Result; R?~h7 d
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/** ~+egu89'TU
* @author Joa jYX9;C;J
*/ 5I1J)K;
publicinterface UserManager { \{zAX~k6
bV*zMoD#
public Result listUser(Page page)throws A9Wqz"[
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HibernateException; <]^;/2.B
:V~*vLvR
} 6.s?
wrYQ=u#Z
rDX'oP:
{IHK<aW
aSkx#mV
java代码: hO.G'q$V
qd~98FS
YG~ o
/*Created on 2005-7-15*/ UX`DZb+^
package com.adt.service.impl; #6sC&w3
-5v.1y=!L
import java.util.List; gQ=POJ=G
S<!_
u q
import net.sf.hibernate.HibernateException; |zq!CLjD@
G+ v, Hi1
import org.flyware.util.page.Page; Rgfhs[Z
import org.flyware.util.page.PageUtil; }K80G~O2<
^Lmc%y
import com.adt.bo.Result; C'czXZtn
import com.adt.dao.UserDAO; nQ17E{^pR
import com.adt.exception.ObjectNotFoundException; :LiDJF
import com.adt.service.UserManager; Jrd4a~XP
Vt=(2d5:p
/** (F[/~~
* @author Joa O+p-1 C$\
*/ tNuC xb-
publicclass UserManagerImpl implements UserManager { j'Y"/<
Dbdzb m7
private UserDAO userDAO; )6:]o&bZ
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/** aZjef
* @param userDAO The userDAO to set. 2\63&C^
*/ 3zTE4pHzu+
publicvoid setUserDAO(UserDAO userDAO){ vk)0n=
this.userDAO = userDAO; 0\Yx.\X,
} ,0uo&/Y4L
[AX"ne#M*
/* (non-Javadoc) [TK? P0
* @see com.adt.service.UserManager#listUser /witDu7
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(org.flyware.util.page.Page) 8| e$
*/ 9;]wF8h
public Result listUser(Page page)throws 5Z6-R}uXk
MkW1FjdP
HibernateException, ObjectNotFoundException { ,+/9K)X
int totalRecords = userDAO.getUserCount(); [Ba2b: l6v
if(totalRecords == 0) ;eW'}&|LV
throw new ObjectNotFoundException r*N~. tFo
:-u-hO5*8
("userNotExist"); <L/M`(:=k
page = PageUtil.createPage(page, totalRecords); S -6"f/
List users = userDAO.getUserByPage(page); ";_K x={
returnnew Result(page, users); U8K&Q4^
} 6<s(e_5f
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} i9;27tT~<
}*.:Hv"
j!S1Y0CV
Qb?y@>-[
AGEZ8(h
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 h7EUIlh"
7~ *;=,mw
询,接下来编写UserDAO的代码: B 9LSxB
3. UserDAO 和 UserDAOImpl: R2N^'
java代码: 13.{Y)
bk7^%O>
&gWMl`3^*!
/*Created on 2005-7-15*/ @TA8^ND
package com.adt.dao; t}]9VD9
c>S"`r
import java.util.List; >G<\1R
Na.
nA
import org.flyware.util.page.Page; KP=D! l&q
t&R!5^R
import net.sf.hibernate.HibernateException; C|4U78f{
|7QVMFZ
/** E 4='m
* @author Joa p*pn@z
*/ Iys6R?~
publicinterface UserDAO extends BaseDAO { HZDk
<aU/!
{ r6]MS#l1
publicList getUserByName(String name)throws MUbhEau?
5;FP.{+
HibernateException; FgOUe
*MYt:ms
publicint getUserCount()throws HibernateException; (|g").L
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publicList getUserByPage(Page page)throws *|];f#^9
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HibernateException; r7Nu>[r5
OgEUq''
} k40Ep(M}
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#
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[)hk&(R
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java代码: w~<FG4@LU
-l-AToO4
=<[7J]%
/*Created on 2005-7-15*/ t/JOERw
package com.adt.dao.impl; ATMc`z:5T
jOBY&W0r
import java.util.List; hz<|W5
!~K=#"T
import org.flyware.util.page.Page; ElQJ\%
uQ:Qb|
import net.sf.hibernate.HibernateException; 6oj4Rg+(
import net.sf.hibernate.Query; DUZQO{V
!Z
U_,[
import com.adt.dao.UserDAO; "?i>p z
f\h%; X
/** ,dHP`j ?
* @author Joa [#7y[<.P
*/ lir&e
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public class UserDAOImpl extends BaseDAOHibernateImpl D3%l4.h
T@(6hEmP,
implements UserDAO { PSW#^o
R'G'&H{N
/* (non-Javadoc) xik`W!1S
* @see com.adt.dao.UserDAO#getUserByName <9@&oN+T
"0|BoG
(java.lang.String) m9#}X_&x
*/ X,>(Y8
publicList getUserByName(String name)throws 3%XG@OgP
^pJ0nY#c
HibernateException { {B@*DQv
String querySentence = "FROM user in class .=Pm>o/,
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o
com.adt.po.User WHERE user.name=:name"; jEZ
"
Query query = getSession().createQuery &nQRa?3,
mYjf5
(querySentence); s,84*6u
query.setParameter("name", name); N\_( w:q
return query.list(); %v]7BV^%6
} ha_@Yqgh
Tv`_n2J`2
/* (non-Javadoc) /r-8T>m
* @see com.adt.dao.UserDAO#getUserCount() xC)7eQn/R
*/ w'd.;
publicint getUserCount()throws HibernateException { GSQfg
int count = 0; a|UqeNI{
String querySentence = "SELECT count(*) FROM
q4_**
gk"mr_03
user in class com.adt.po.User"; D2Y&[zgv
Query query = getSession().createQuery F
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`Gf{z%/
(querySentence); SLSF
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count = ((Integer)query.iterate().next y0;,dv]
8,=G1c
()).intValue(); (%i!%{!]
return count; =h(7rU"Yz
} iNt 4>
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/* (non-Javadoc) _]P
a>8X*
* @see com.adt.dao.UserDAO#getUserByPage _=uviMuE
%=BtOM_2
(org.flyware.util.page.Page) .
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*/ ^,Xa IP+[
publicList getUserByPage(Page page)throws 60'6/3
L5/mO6;k
HibernateException { #`vVgGZ&
String querySentence = "FROM user in class 658\#x8|
ja?s@Y}-9s
com.adt.po.User"; VW {,:Ya
Query query = getSession().createQuery }bp.OV-+
3a%xn4P
(querySentence); 5|CzX X#U
query.setFirstResult(page.getBeginIndex()) L4~
W/6A
.setMaxResults(page.getEveryPage()); $cq!RgRn
return query.list(); 7iP5T
} ?C}sR: K/
^ZR8s^X
} O"qR }W
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:U<
O5O.><RP
至此,一个完整的分页程序完成。前台的只需要调用 ikr7DBLt
XYts8}y5
userManager.listUser(page)即可得到一个Page对象和结果集对象 "i&fp:E0
|IAW{_9)U
的综合体,而传入的参数page对象则可以由前台传入,如果用 +Jdm#n?_
Gp,'kw"I
webwork,甚至可以直接在配置文件中指定。 :v_w!+,/
x =h0Fq,T
下面给出一个webwork调用示例: 4 HW;
java代码: )Xp Vu
/V#7=,,
#J\s%60pt
/*Created on 2005-6-17*/ dKb ^x^
package com.adt.action.user; Gh'X.?3
|<1M&\oaQ'
import java.util.List; S4)A6z$
kAeNQRjR
import org.apache.commons.logging.Log; KYf;_C,$
import org.apache.commons.logging.LogFactory; fL2^\dB;
import org.flyware.util.page.Page; !f`5B( @
[$;,Ua-mt
import com.adt.bo.Result; W=3? x
import com.adt.service.UserService; V;k#})_-
import com.opensymphony.xwork.Action; l**3%cTb
P0)AUi
/** 0TmZ*?3!4
* @author Joa hD*(AJ
*/ &5d\~{;
publicclass ListUser implementsAction{ /w0w*nH
,aWCiu}
privatestaticfinal Log logger = LogFactory.getLog pUGN!3
dkpQZXi9%
(ListUser.class); # v+;:
FJ}gUs{m
private UserService userService; -qfnUh
$,@JYLC2
private Page page; y`6\L$c
Gp8psH
privateList users; fQO
""qh
U:\p$ hL9
/* BtzYA"
* (non-Javadoc) ^;4YZwW5w
* a5)JkC
* @see com.opensymphony.xwork.Action#execute() V,m3-=q
*/ W/=7jM
publicString execute()throwsException{ <