Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ESb
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ud!iy
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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 [@.%6aD
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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 uKhfZSx0w
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分页支持类: ^Cpvh}1#
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java代码: 2NI3&;{4
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package com.javaeye.common.util; !QP~#a%
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import java.util.List; TRX; m|
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publicclass PaginationSupport { -1Tws|4gc
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publicfinalstaticint PAGESIZE = 30; a?&oOQd-iP
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privateint pageSize = PAGESIZE; ]\*g/QV
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privateList items; Z2hRTJJ[A
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privateint totalCount; Hza{"I*^
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privateint[] indexes = newint[0]; Exk[;lI
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privateint startIndex = 0; lSl=6R
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public PaginationSupport(List items, int ^!N _Nx/M
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totalCount){ R\1#)3e0
setPageSize(PAGESIZE); d];E99}
setTotalCount(totalCount); j$Gb>Ex>
setItems(items); @yS
setStartIndex(0); rhwY5FD?
} o#H"tYP
!,INrl[
public PaginationSupport(List items, int A)s
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totalCount, int startIndex){ h#'(UZ
setPageSize(PAGESIZE); Kh'/Ne?
setTotalCount(totalCount); ,W7\AY07]
setItems(items);
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setStartIndex(startIndex); Y(W>([59
} u
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public PaginationSupport(List items, int >mi%L3Pk
[:TOU^
totalCount, int pageSize, int startIndex){ $kvF]|<bu
setPageSize(pageSize); D=o9+5Slw
setTotalCount(totalCount); Quc9lL
setItems(items); 91}QuYv/_
setStartIndex(startIndex); K zKHC
} Vv0dBFe
d]$z&E
publicList getItems(){ >}43MxU?
return items; Cd"O'<^Sb
} 9)3ok#pQ/
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publicvoid setItems(List items){ 6rF[eb
this.items = items; "Z#97Jc+J
} M
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6 80i?=z
publicint getPageSize(){ n*{e0,gp`
return pageSize; u&9|9+"N
} 1 nIb/nY
LoPWho[8
publicvoid setPageSize(int pageSize){ ^mm:u<Yt
this.pageSize = pageSize; 0<Vw0%!
} # G0jMQ
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publicint getTotalCount(){ M#IGq
return totalCount; 6~ev5SD;f
} Xd!=1::
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publicvoid setTotalCount(int totalCount){ !6'j
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if(totalCount > 0){ EXK~Zf|&Z
this.totalCount = totalCount; %TyR8
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int count = totalCount / 9mIq9rQ|*
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pageSize; P`v%<
9~
if(totalCount % pageSize > 0) !E'jd72O
count++; ygW,4Vz7J
indexes = newint[count]; & ;ie+/B
for(int i = 0; i < count; i++){ vq
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indexes = pageSize * Jk!}z+X'A
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i; 7[[XNJP
} ?{mFQ
}else{ N J9H=
this.totalCount = 0; 79AOvh
} 4Cr|]o'
} iEux`CcJ.
n{J<7I e"*
publicint[] getIndexes(){ Z)Nl\e& M
return indexes; 2VyLt=mdh
} Ev|2bk \
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publicvoid setIndexes(int[] indexes){ }rz}>((ZHF
this.indexes = indexes; lwIU|T<4
} /m%i"kki
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publicint getStartIndex(){ u* G|TF
return startIndex; :(VD<"X
} g!(j.xe
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publicvoid setStartIndex(int startIndex){ 3de<H=H'
if(totalCount <= 0) EtK,C~C}8
this.startIndex = 0; !run3ip`Z
elseif(startIndex >= totalCount) #8z2>&:|
this.startIndex = indexes MQ9 9fD$
!>W _3Ea
[indexes.length - 1]; *aT3L#0(
elseif(startIndex < 0) -bdF=
this.startIndex = 0; lPFT)>(+@
else{ X!V@jo9?
this.startIndex = indexes kaQn'5
*[t@j*al
[startIndex / pageSize]; "l6v[yv
} B@D3aOvO
} E#X(0(A)
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publicint getNextIndex(){ Wg9q_Ql
int nextIndex = getStartIndex() + w0(A7L:L
NitWIj[U;
pageSize; ?NoG.
if(nextIndex >= totalCount) fx2r\ usX[
return getStartIndex(); vzA)pB~;
else CKeT%3
return nextIndex; 4Z5ZV!
} UM%]A'h2O"
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publicint getPreviousIndex(){ *U|K~dl]K
int previousIndex = getStartIndex() - gZF-zhnC
MgyV{`
pageSize; s ki'I
if(previousIndex < 0) =S7Xj`/
return0; :^]rjy/|+
else E9JxntX
return previousIndex; Ucr$5^ME
} #e:cB' f
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} Gv?3T Am8
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抽象业务类 *\><MXx
java代码: Dz4e.tvN
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/** |Xz-rgkQ
* Created on 2005-7-12 uL| Wuq
*/ M,nX@8 _h
package com.javaeye.common.business; L|O[u^
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import java.io.Serializable; u*LMpTnn
import java.util.List; 6Q\0v
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import org.hibernate.Criteria; t&m8 V$Q
import org.hibernate.HibernateException; IL*Ghq{/
import org.hibernate.Session; KWwEK]
import org.hibernate.criterion.DetachedCriteria; U4`6S43ki
import org.hibernate.criterion.Projections; eQK}J]S<
import vKrOIBP
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org.springframework.orm.hibernate3.HibernateCallback; C{Y0}ZrmlF
import $=&a0O#
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org.springframework.orm.hibernate3.support.HibernateDaoS [\|`C4@3a
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upport; |AD"}8
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import com.javaeye.common.util.PaginationSupport; LdAWCBLS
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public abstract class AbstractManager extends ,v<GSiO
p ~LTu<*S
HibernateDaoSupport { (^),G-]
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privateboolean cacheQueries = false; ~bC-0^/
8|
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privateString queryCacheRegion; R*S9[fqC[
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publicvoid setCacheQueries(boolean r1pj-
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cacheQueries){ &oJ1v<`
this.cacheQueries = cacheQueries; kh7RQbNY<I
} E}qW'
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publicvoid setQueryCacheRegion(String ab-z 7g
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queryCacheRegion){ g]$e-X@k
this.queryCacheRegion = GMv.G
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queryCacheRegion; |!Uul0O
} qpt},yn)C
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publicvoid save(finalObject entity){ s*;rt
getHibernateTemplate().save(entity); Y|
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} f*%Y]XL;%
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publicvoid persist(finalObject entity){ d~QZcR
getHibernateTemplate().save(entity); &mPR[{
} 7=wPd4
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publicvoid update(finalObject entity){ r9
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getHibernateTemplate().update(entity); <V
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} bxc!x>)
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publicvoid delete(finalObject entity){ S%6 V(L|
getHibernateTemplate().delete(entity); A[hvT\X
} ^D]y<@01
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publicObject load(finalClass entity, j>I.d+
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finalSerializable id){ (>,}C/-UG
return getHibernateTemplate().load _(_U=
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(entity, id); p!o+8Xz5
} 8b|m6 6#|
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publicObject get(finalClass entity, w:|YOeP
@tfatq+q
finalSerializable id){ d-ML[^G
return getHibernateTemplate().get p9Y`_g`
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(entity, id);
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} [E:-$R
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publicList findAll(finalClass entity){ o#frNT}
return getHibernateTemplate().find("from d$<1Ma}
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" + entity.getName()); MngfXm
} W:y'a3~
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publicList findByNamedQuery(finalString yoVN|5
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namedQuery){ Y6ORI
return getHibernateTemplate IfF&QBi
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().findByNamedQuery(namedQuery); V?C_PMa
} uTIl} N
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publicList findByNamedQuery(finalString query, i=s>a;*#
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finalObject parameter){ ,}HnS)+
return getHibernateTemplate r57rH^Hc
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().findByNamedQuery(query, parameter); I.L8A|nZ
} bl-t>aO*.V
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publicList findByNamedQuery(finalString query, r/BiR0$E
7).zed^
finalObject[] parameters){ gA~faje
return getHibernateTemplate Tx0l^(n
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().findByNamedQuery(query, parameters); Ykt(%2L
} $C ?G7Vs
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publicList find(finalString query){ sow/JLlbC
return getHibernateTemplate().find Mb[4G>-v=
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(query); h|
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} WX9pJ9d
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publicList find(finalString query, finalObject Zjh9jvsW
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parameter){ )#n>))
return getHibernateTemplate().find j[o5fr)L
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(query, parameter); @5-+>\Hd^t
} )gAFz+
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public PaginationSupport findPageByCriteria \ml6B6
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(final DetachedCriteria detachedCriteria){ |uE_aFQs
return findPageByCriteria pd{;`EW|
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 'd@Vusq}2
} 4c_F>Jw[
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public PaginationSupport findPageByCriteria oFeflcSz
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(final DetachedCriteria detachedCriteria, finalint x{|n>3l`b9
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startIndex){ ?JD\pYg[/
return findPageByCriteria &sx|sLw)
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(detachedCriteria, PaginationSupport.PAGESIZE, D{,B[5
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startIndex); B&m?3w
} nA]dQ+5sT
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public PaginationSupport findPageByCriteria }m<)$.x|P
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(final DetachedCriteria detachedCriteria, finalint IfZaK([
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pageSize, j1>77C3
finalint startIndex){ ZtEHP`Iin
return(PaginationSupport) MQ>vHapr
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getHibernateTemplate().execute(new HibernateCallback(){ uBks#Y*3$
publicObject doInHibernate *0R=(Gy
" I@Z:[=2
(Session session)throws HibernateException { {-S0m=
Criteria criteria = \Rp)n=|
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detachedCriteria.getExecutableCriteria(session); CFZ=!s)B
int totalCount = =I/J !}.
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((Integer) criteria.setProjection(Projections.rowCount !@/?pXt|
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()).uniqueResult()).intValue(); L#u6_`XJ+
criteria.setProjection 4:<0i0)5
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(null); SQ5*?u\
List items = Sjr(e}*
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criteria.setFirstResult(startIndex).setMaxResults z<<` 1wqg
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(pageSize).list(); 6w}:w?=6
PaginationSupport ps = 8d)F#
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new PaginationSupport(items, totalCount, pageSize, ]NAPvw#p
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startIndex); m;
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return ps; :`
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} RV(}\JU
}, true); Op%^dwVG(v
} (Z,,H1L
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public List findAllByCriteria(final 9D#PO">|
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DetachedCriteria detachedCriteria){ uEi!P2zN
return(List) getHibernateTemplate 2qr%xK'^B
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().execute(new HibernateCallback(){ 4UL-j
publicObject doInHibernate x:2[E-
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(Session session)throws HibernateException { Y*}Sq|y
Criteria criteria = A:NY:#uC
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detachedCriteria.getExecutableCriteria(session); /BIPLDN6
return criteria.list(); 2#!$f_
} ;OKQP~^iH2
}, true); .M!
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} ttw@nv%
@
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public int getCountByCriteria(final _&z>Id`w
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DetachedCriteria detachedCriteria){ df:,5@CJ8
Integer count = (Integer) %d7iQZb>
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getHibernateTemplate().execute(new HibernateCallback(){ Z0'3.D,l
publicObject doInHibernate b]Y,& 8}[+
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(Session session)throws HibernateException {
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Criteria criteria = =0:hrg+Zgx
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detachedCriteria.getExecutableCriteria(session); AHA*yC
return @!MbPS
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criteria.setProjection(Projections.rowCount zV&3l9?U
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()).uniqueResult(); zR
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} 7RLh#D|
}, true); ]S[r$<r$
return count.intValue(); ~8X'p6
} LH_ 2oJ\
} CeJ|z{F\
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用户在web层构造查询条件detachedCriteria,和可选的 # SXXYh-e
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 xn@jL;+<-
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PaginationSupport的实例ps。 s_[?(Ip{
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ps.getItems()得到已分页好的结果集 8vRiVJ8QS:
ps.getIndexes()得到分页索引的数组 lrE0)B5F
ps.getTotalCount()得到总结果数 F,zJdJ
ps.getStartIndex()当前分页索引 |<V{$),k
ps.getNextIndex()下一页索引 9mnON~j5
ps.getPreviousIndex()上一页索引 |l|]Tw
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~V&ReW/
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 kT1lOP-Bg
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一下代码重构了。 ~<%cc+;`
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我把原本我的做法也提供出来供大家讨论吧: 8if"U xV(
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首先,为了实现分页查询,我封装了一个Page类: f+6l0@K2
java代码: GCKl[<9*
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/*Created on 2005-4-14*/ >+#[O"
package org.flyware.util.page; (Gn[T1p?
7q 2YsI
/** .T|NB8 rS
* @author Joa xD=D *W
* {P-PH$ E-
*/ ^sKXn:)
publicclass Page { "!tB";n
*K(xES!b
/** imply if the page has previous page */ 1I`D$Xq~:
privateboolean hasPrePage; L@Z
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4.'EEuRw\}
/** imply if the page has next page */ + LwoBn>6
privateboolean hasNextPage; D$cMPFa2Nt
*ls6#j@
/** the number of every page */ bwJi[xF
privateint everyPage;
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@nP}q!y
/** the total page number */ {Y[D!W2y
privateint totalPage; DVJc-.x8
VO Qt{v{1|
/** the number of current page */ deoM~r9s
privateint currentPage; .y/b$|d,
$D5U#
/** the begin index of the records by the current I[UA' ~f
k%g xY% 0
query */ J[H?nX9
privateint beginIndex; r!^\Q7
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/** The default constructor */ m_2P{
public Page(){ !r*;R\!n2
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} /09=Tyy/\
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/** construct the page by everyPage Q/c
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* @param everyPage Lf#G?]@
* */ _6!/}Fm
public Page(int everyPage){ aS vE
this.everyPage = everyPage; h'~-K`
} kZ9<j+.
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/** The whole constructor */ j>xVy]v= |
public Page(boolean hasPrePage, boolean hasNextPage, fWyDWU
:dN35Y] a
!&O/7ywe
int everyPage, int totalPage, A#X.c=
int currentPage, int beginIndex){ *BsDHq-F~
this.hasPrePage = hasPrePage; `M ygDG+u
this.hasNextPage = hasNextPage; &8_;:
this.everyPage = everyPage; +^?-}v
this.totalPage = totalPage; 2g6_qsqi
this.currentPage = currentPage; //lZmyP?
this.beginIndex = beginIndex; Iv72;ZCh?6
} ]7kGHIJ|
s ;s-6%p
/**
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* @return nnL$m_K~
* Returns the beginIndex. oks=|'&
*/ x{>Y$t]
publicint getBeginIndex(){ iBQBHF
return beginIndex; 93IOG{OAY
} sBtG}Mo)
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/** LGRO En<*d
* @param beginIndex P0 ltN
* The beginIndex to set. )O@^H
*/ Y-q@~vZ]
publicvoid setBeginIndex(int beginIndex){ 5
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this.beginIndex = beginIndex; "42$AaS
} o
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/** >zg8xA1zL
* @return &]6K]sWJK{
* Returns the currentPage. Kn#xY3W6
*/ CS5jJi"pD3
publicint getCurrentPage(){ a^c,=X3
return currentPage; N~5WA3xd
} HwW[M[qA
u45h{i-e
/** o|qeh<2=x
* @param currentPage U.Chf9a-
* The currentPage to set. 5u)^FIBj
*/ {0vbC/?]
publicvoid setCurrentPage(int currentPage){ EO/cW<uV'
this.currentPage = currentPage; RO$@>vL
} (
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1gShV ]2
/** o\ow{gh9
* @return y'!p>/%v
* Returns the everyPage. +%}5{lu_e
*/ B N*,!fx
publicint getEveryPage(){ 3cfZ!E~^kc
return everyPage; CESe}^)n
} Wytvs*\`
t7oz9fSz=?
/** rfXF 01I
* @param everyPage "UoCT7X
* The everyPage to set. )fd-IYi-3
*/ O3C)N
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publicvoid setEveryPage(int everyPage){ 0Dm`Ek3A7x
this.everyPage = everyPage; !
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} nhP~jJn
oyN+pFVB:$
/** ccN &h
* @return /cL9?k;o
* Returns the hasNextPage. [wy3Ld
*/ ;;y@z[ >
publicboolean getHasNextPage(){ z<[.MH`ln
return hasNextPage; U.pr} hq
} @0UwI%.
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/** Eo {1y
* @param hasNextPage
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* The hasNextPage to set. +<!)k?
*/ "`jZ(+
publicvoid setHasNextPage(boolean hasNextPage){ 1!;"bHpk
this.hasNextPage = hasNextPage; s;_#7x#
} 3\p]esse
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/** zfjD b
* @return +%e%UF@
* Returns the hasPrePage. h2/dhp
*/ U-~*5Dd
publicboolean getHasPrePage(){ .}$`+h8WT
return hasPrePage; Y1yXB).AH8
} f^6&Fb>
g`)/ x\
/** igRDt{}
* @param hasPrePage ^i`3cCFB<
* The hasPrePage to set. E2q B:
*/ z6FbM^;;
publicvoid setHasPrePage(boolean hasPrePage){ Pa+AF
this.hasPrePage = hasPrePage; #"o6OEy$A#
} gQI(=in
tv@Z5
/** DV7<n&P
* @return Returns the totalPage. 3Y1TQ;i,wQ
* (!_X:+0_
*/ r>@ B+Xi
publicint getTotalPage(){ P,$[|)[E
return totalPage; PtRj9TT
} 1%SJ1oY
|~/3u/
/** ^^4K/XBve
* @param totalPage W;OYO
* The totalPage to set. Jm]]>K8.3V
*/ vGPf`2/j.
publicvoid setTotalPage(int totalPage){ _o &,
this.totalPage = totalPage; taWirqd9
} 8"?Vcw&
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} HC9vc,Fp
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c]%;^)
@o4z3Q@
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 %S
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个PageUtil,负责对Page对象进行构造: Yn IM-
java代码: ~>N`<S
mc0sdb,c$
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/*Created on 2005-4-14*/ nJldz;
package org.flyware.util.page; 12:h49AP
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import org.apache.commons.logging.Log; `zElBD
import org.apache.commons.logging.LogFactory; Pg*?[^*
abTDa6 /`v
/** |aI|yq)
* @author Joa IL+#ynC
* XI%RneuDr:
*/ +X* F<6mZ
publicclass PageUtil { ' D)1ka.
K)Df}fVOc
privatestaticfinal Log logger = LogFactory.getLog CU#L *kz
27Kc-rcB
(PageUtil.class); zK'
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/** dl*_ m3T
* Use the origin page to create a new page U,%s;
* @param page Q-!
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* @param totalRecords RlI
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* @return >~`Y
*/ mC*W2#1pF
publicstatic Page createPage(Page page, int 26\HV
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totalRecords){ ]Wy^VcqX
return createPage(page.getEveryPage(), [ -9)T
V9 +xL 1U#
page.getCurrentPage(), totalRecords); =Q/w% 8G
} W; 3
R;
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/** Z-4K?;g'k
* the basic page utils not including exception m+D2hK*
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handler =gMaaGg p,
* @param everyPage ' +)6#/*
* @param currentPage -{yDk$"
* @param totalRecords DHh+%|e
* @return page SBCL1aM
*/ _/8_,9H
publicstatic Page createPage(int everyPage, int |Q5H9<*
k9*J*7l-m
currentPage, int totalRecords){ ax-=n (
everyPage = getEveryPage(everyPage); 4'+d"Ok
currentPage = getCurrentPage(currentPage); T4V[RN
int beginIndex = getBeginIndex(everyPage, 96.IuwL*.s
SjZd0H0
currentPage); 3gxf~$)?
int totalPage = getTotalPage(everyPage, U-Af7qO
#t"9TP
totalRecords); vqrBRlZ
boolean hasNextPage = hasNextPage(currentPage, M*g2VyZ
#@nZ4=/z
totalPage); Mq+viU&
boolean hasPrePage = hasPrePage(currentPage); C!$Xv&"r
z7'n, [
returnnew Page(hasPrePage, hasNextPage, ]sX7%3P
everyPage, totalPage, &M0o&C-1/
currentPage, pd=7^"[};
N; rXl8
beginIndex); Am2*-
} '4af
],
}U2[?
privatestaticint getEveryPage(int everyPage){ .LX?VD
return everyPage == 0 ? 10 : everyPage; PRMZfYc
} 21.YO]Et
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privatestaticint getCurrentPage(int currentPage){ \1=T
sU&^
return currentPage == 0 ? 1 : currentPage; rER~P\-
} f2uZK!:m
UqD5
A~w
privatestaticint getBeginIndex(int everyPage, int NY~ dM\
Hm.X}HO0L
currentPage){ R!sNg
return(currentPage - 1) * everyPage; n
(OjjRm
}
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o:Ln._bj
privatestaticint getTotalPage(int everyPage, int RM)1*l`!E
FpP\-+Sl
totalRecords){ a^@+%?X
int totalPage = 0; r`?&m3IOP
?+3R^%`V
if(totalRecords % everyPage == 0) \U==f&G?J
totalPage = totalRecords / everyPage; {]+ jL1
else TAXd,z N
totalPage = totalRecords / everyPage + 1 ; F?!FD>L{`
BfX%|CWh
return totalPage; 0Wa#lkn$I
} g;$E1U=R-E
HkW/G[7x&
privatestaticboolean hasPrePage(int currentPage){ 8r5xs-
return currentPage == 1 ? false : true; DG_}9M!DW@
} jjxIS
RI?NB6U
privatestaticboolean hasNextPage(int currentPage, w#W5}i&x
AdDQWJ^r
int totalPage){ }%_qx|(P|t
return currentPage == totalPage || totalPage == HTxB=Q|
O:2 #_
0 ? false : true; Tsu\oJ[
} %wOOzp`
y@q1c*|
QxKAXq@)i
} [.M
ty':`)
QyTh!QM~`
IoQr+:_R
yU> T8oFh
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。 'T%IvJ#Xu
O2C6V>Q;
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 ] OUD5T
$H4=QVj6
做法如下: r~I.F!{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 RvWFF^, .
4 uShM0qa
的信息,和一个结果集List: #U\$@4D
java代码: t/ A:k
Pv#KmSA9
6s'[{Ov
/*Created on 2005-6-13*/ VZ;@S3TS
package com.adt.bo; O)l%OOv
%j%%Rn
import java.util.List; 6{L F-`S%
V!mWn|lf
import org.flyware.util.page.Page; )#C_mB$-#
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/** OthG7+eF
* @author Joa 61G|?Aax
*/ -H4PRCDH
publicclass Result { JW-|<CJ
X!o@f$
private Page page; !!9{U%s
.-J`d=Krp
private List content;
j|ozGO
[;<<4k(nL
/** wI*Y{J
* The default constructor @ozm;
*/ qZ#!CPHS
public Result(){ : sFo
super(); &ryiG
} [
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V
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/** Sq<3Rw
* The constructor using fields :r\xkHg/f
* So?m?,!W
* @param page ej<`CQ
* @param content :|=- (z
*/ h5j<u
public Result(Page page, List content){ TWtC-wI;
this.page = page; 3=IG#6)~C
this.content = content; $%B5$+
} _n7%df
h:_NA
/** {QMN=O&n
* @return Returns the content. O
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*/ WBa /IM
publicList getContent(){ ;>5,
return content; ,|A{!j`
} S3QaYq"v
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/** _;#9!"&
* @return Returns the page. 2av*o~|J*:
*/ Zct!/u9 Q
public Page getPage(){ z1#oWf{*
return page; ,^HS`!s[ E
} (N7O+3+G
{|Bd?U;
/** \,hrk~4U;(
* @param content #.o0mguU
* The content to set. Q]^Yi1PbS
*/ <;aJ#qT
public void setContent(List content){ !KAsvF,j
this.content = content; 9]Lo
} `wf|u M
6vF/e#},
/** $Vsy%gA<
* @param page 9?$RO[vo
* The page to set. x`#22"m
*/ BK*z 4m
publicvoid setPage(Page page){ 7r['
this.page = page; 1EQvcw#
} ;KL9oV!<f
} p+vh[+yp
&lU Ny
L
RNvQ
D@:"f?K>
t|<FA#
2. 编写业务逻辑接口,并实现它(UserManager, q#jEv- j.
my4\mi6P
UserManagerImpl) S{-f$Q*
java代码: G@B*E%$9
Tn /Ut}]O
22|"K**3J|
/*Created on 2005-7-15*/ r
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package com.adt.service; 'd+:D'
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import net.sf.hibernate.HibernateException; .N!{ U
6W$rY] h!
import org.flyware.util.page.Page; [1Uz_HY["3
i_NJ -K
import com.adt.bo.Result; uS&LG#a
0`6),R'x
/** rtus`A5p
* @author Joa ![).zi+m
*/ A*R n<{U
publicinterface UserManager { o _(0
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public Result listUser(Page page)throws D,E$_0
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HibernateException; $e*B:}x}
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} (uRZxX
"Tv:*L5
`[OXVs,7"
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l0:5q?g
java代码: ld95[cTP
1#q^uqO0
5N1}Ns
/*Created on 2005-7-15*/ aLYLd/ KV
package com.adt.service.impl; 'g~@"9'oe
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import java.util.List; o)p[
C
gJK KR]4*
import net.sf.hibernate.HibernateException; K?[)E3
^&-a/'D$,
import org.flyware.util.page.Page; dqxd3,Z
import org.flyware.util.page.PageUtil; L_k9g12
%E aE,
import com.adt.bo.Result; |Q5+l.%
import com.adt.dao.UserDAO; K\aAM;)-
import com.adt.exception.ObjectNotFoundException; JN|VPvjE
import com.adt.service.UserManager; M7vj^mt?
N ocFvF7\
/** S~> 5INud
* @author Joa xD4$0Ppu
*/ #)`\!)?
publicclass UserManagerImpl implements UserManager { 26 ?23J
;
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private UserDAO userDAO;
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/** rd"
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* @param userDAO The userDAO to set. @701S(0'7
*/ 1AT'S;`
publicvoid setUserDAO(UserDAO userDAO){ pqH4w(;
this.userDAO = userDAO; FQ!Oxlq,Q
} wFb@1ae\
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/* (non-Javadoc) Dkw*Je#6PX
* @see com.adt.service.UserManager#listUser Z\' wm'
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(org.flyware.util.page.Page) :!']p2B
*/ 'W(xgOP1
public Result listUser(Page page)throws (AuPZ
"S(yZ6r"
HibernateException, ObjectNotFoundException { e3g_At\
int totalRecords = userDAO.getUserCount(); rREzM)GA
if(totalRecords == 0) /BKtw8
throw new ObjectNotFoundException ]4o?BkL
oq. r\r
("userNotExist"); ??(Kwtx{
page = PageUtil.createPage(page, totalRecords); ~&KX-AC@
List users = userDAO.getUserByPage(page); '?8Tx&}U8
returnnew Result(page, users); # 66e@
} >XnO&hW
Um\0i;7 ~4
} ;ctU&`
;cLUnsB\
6__K#r
i.M2E$b|
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 akCIa'>t
?+\E3}:
询,接下来编写UserDAO的代码: ($SLb6
3. UserDAO 和 UserDAOImpl: 7E~4)k0<
java代码: ?:/|d\,7@
<m]wi7
S=PJhAF
/*Created on 2005-7-15*/ W&KM/9d
package com.adt.dao; S(w\Z C
!W~<q{VTs
import java.util.List; nB&j
R04J3D|
import org.flyware.util.page.Page; > 0T
Za
SX_4=^
import net.sf.hibernate.HibernateException; H(&Z:{L
Q6x%
/** [O1|75
* @author Joa CKd3w8;
*/ t!~S9c
publicinterface UserDAO extends BaseDAO { + Kk@Q
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publicList getUserByName(String name)throws :1MMa6
.`J:xL%Z
HibernateException; GO~k '
gl
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publicint getUserCount()throws HibernateException; y
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#KE;=$(S
publicList getUserByPage(Page page)throws hy!6g n
n| C|&
HibernateException; o_rtH|ntX5
6p m~sD
} j|(:I: ]
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W_}/ O'l{
'\t7jQ
O]ZC+]}/
java代码: ]nc2/S%
._,trb>o
50Ad,mn<
/*Created on 2005-7-15*/ s#P:6]Ar
package com.adt.dao.impl; sUciFAb
'hIU_
import java.util.List; +>#e=nH
M5O'=\+,F
import org.flyware.util.page.Page; $eX*
s5AgsMq
import net.sf.hibernate.HibernateException; iC*U $+JG
import net.sf.hibernate.Query; q~h:<,5
Mpm#GdT
import com.adt.dao.UserDAO; ^*>n4U
-)RJ\V^{9
/** j)";:v
* @author Joa zt?H~0$LB
*/ #HG&[Ywi
public class UserDAOImpl extends BaseDAOHibernateImpl DqlK.
2LK]Q/WG,+
implements UserDAO { ]3+`` vL
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/* (non-Javadoc) }p*?1N
* @see com.adt.dao.UserDAO#getUserByName H+`*Y<F@
*B{-uc3o
(java.lang.String) v$3_o :
*/ #_fY4vEO
publicList getUserByName(String name)throws tW(+xu36
[+gzdLad
HibernateException { l&|)O6N
String querySentence = "FROM user in class &k+*3.X
ev"M;"y
com.adt.po.User WHERE user.name=:name"; JY@X2'>v/
Query query = getSession().createQuery )&z4_l8`=
Pi){ h~B>
(querySentence); <jFSj=cIL
query.setParameter("name", name); =ybGb7?
return query.list(); 5~[N/Gl
} ~6sE an3p
H%C\Uz"o
/* (non-Javadoc) yQwVQUW8B
* @see com.adt.dao.UserDAO#getUserCount() waQtr,m)
*/ rhoeZ
publicint getUserCount()throws HibernateException { x.\XUJ4x
int count = 0; lY,/ W
String querySentence = "SELECT count(*) FROM T.2ZBG~|[
ZpWu,1
user in class com.adt.po.User"; i@6wO?Tv
Query query = getSession().createQuery $3 vhddO
>%h7dC3h
(querySentence); R,b59,&3/
count = ((Integer)query.iterate().next ymkR!
o8tS
()).intValue(); 0[9I0YBJ
return count; Mr.JLW
} L$}g3{
PGY9*0n
/* (non-Javadoc) }$:#+
(17
* @see com.adt.dao.UserDAO#getUserByPage u<kD}
9v$qrM`8
(org.flyware.util.page.Page) <soj&f+
*/ s|gp
publicList getUserByPage(Page page)throws gIBpOPr^d
kO+s+ 55
HibernateException { %YCd%lAe,
String querySentence = "FROM user in class m>YWxa
<`+zvUx^?
com.adt.po.User"; f?0D%pxc}&
Query query = getSession().createQuery 17i$8
y;:]F|%<
(querySentence); ((cb4IX
query.setFirstResult(page.getBeginIndex()) 6Hn)pD#U
.setMaxResults(page.getEveryPage()); lC2?sD$
return query.list(); P}l#VJWp
} _uJVuCc
>HIt}Zh
} ZOn_dYjC
J|q^+K
BkV(81"C
jN {Zw*
H|K("AVP:
至此,一个完整的分页程序完成。前台的只需要调用 [ze/@29
w%rg\E
userManager.listUser(page)即可得到一个Page对象和结果集对象 pZ\$50t&O
\gd6Yx^[
的综合体,而传入的参数page对象则可以由前台传入,如果用 3&9zGy{V+
RpAiU
webwork,甚至可以直接在配置文件中指定。 `VXZ khm
*/Cj$KY70
下面给出一个webwork调用示例: 7t3X`db
java代码: ^r4|{
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0 {,h.:
/*Created on 2005-6-17*/ V&R$8tpz
package com.adt.action.user; .HCaXFW
R=Ymo.zs6
import java.util.List; 5v3RVaqZ
/6jGt'^U
import org.apache.commons.logging.Log; wibwyzo
import org.apache.commons.logging.LogFactory; &N9IcNP
import org.flyware.util.page.Page; QXB|!'
"qgu$N4/>
import com.adt.bo.Result; {NV:|M !
import com.adt.service.UserService; \=Nm5:
import com.opensymphony.xwork.Action; U3N(cFXn
Th/{x
h
/** /ISLVp%H
* @author Joa Q ]0r:i=
.
*/ O a1'oYIHg
publicclass ListUser implementsAction{ eK*W=c#@
kXMP=j8
privatestaticfinal Log logger = LogFactory.getLog >fg4x+0 %
tO`?{?W7
(ListUser.class); s,kU*kHn
}\VX^{ K j
private UserService userService; 5pmQp}}R
c(E,&{+E
private Page page; /:KQAM0
C
rfRLsN]
privateList users; zu C5@jy.x
2md.S$V$,
/* PK}vh%
* (non-Javadoc) ?^F5(B[+Y
* AygvJeM_W
* @see com.opensymphony.xwork.Action#execute() $NdH*
*/ 3u4:l
publicString execute()throwsException{ VAg68EbnF
Result result = userService.listUser(page); dxntGH< O
page = result.getPage(); EZ `}*Yrd
users = result.getContent(); V $>"f(
return SUCCESS; ([tG y
} D Kq-C%
? osfL
/** %b9fW
* @return Returns the page. ]xYa yN!n
*/ &8afl"_~
public Page getPage(){ s_v}=C^
return page; @'Q%Jc(
} e lay
=%)
9ClF<5?M
/** {IrJLlq
* @return Returns the users. 7~D`b1||
*/ 4/f[`].#W
publicList getUsers(){ YLigP"*~^
return users; LC76 Qi;|k
} ho_4fDv
7g8B'ex J
/** aTX]+tBoe
* @param page t%:G|n Sz
* The page to set. #.b^E3#+
*/ *.xZfi_|
publicvoid setPage(Page page){ Stt* 1gT
this.page = page; MorW\7-}
} I X?@~'
egbb1+tY
/** zG<0CZQ8
* @param users "!^c
* The users to set. 'cYQ?;
*/ u,\xok"
publicvoid setUsers(List users){ (c<