Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 JXQh$hs
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4`/Td?THx
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 !:3X{)4
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ows3%
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分页支持类: 1O2jvt7M
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java代码: yYiu69v
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package com.javaeye.common.util; 5S
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import java.util.List; 9xOTR#B:_V
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publicclass PaginationSupport { Zg$RiQ^-{J
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publicfinalstaticint PAGESIZE = 30; ~oz??SX
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privateint pageSize = PAGESIZE; Ejj+%)n.
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privateList items; y' RQ_Gi
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privateint totalCount; q0{ _w
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privateint[] indexes = newint[0]; }=p+X:k=
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privateint startIndex = 0; PZihC
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public PaginationSupport(List items, int g\1|<jb3
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totalCount){ :6J&%n
setPageSize(PAGESIZE); /vs79^&
setTotalCount(totalCount); Ch_eK^ g1
setItems(items); RMHJI6?LB
setStartIndex(0); Xi0fX$-,
} g(dReC
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public PaginationSupport(List items, int ;)q"X>FMZe
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totalCount, int startIndex){ (_=R<:
setPageSize(PAGESIZE); {uurLEe?
setTotalCount(totalCount); 3.6Gh|7
setItems(items); JPM~tp?;<
setStartIndex(startIndex); :!wl/X
~
} *tfD^nctO
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public PaginationSupport(List items, int Lk.tEuj=82
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totalCount, int pageSize, int startIndex){ OMAvJzK .
setPageSize(pageSize); $r)NL
setTotalCount(totalCount); n(W&GSj|u9
setItems(items); Muyi2F)j
setStartIndex(startIndex); 7Q9| P?&:z
} }$b!/<7FD
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publicList getItems(){ aKintb}n
return items; |nBs(>b
} Q5HSik4
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publicvoid setItems(List items){ 54#P
this.items = items; FuC\qF
} xdh%mG:?
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publicint getPageSize(){ Py#TXzEcC
return pageSize; #gVWLm<
} SqZ .}s
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publicvoid setPageSize(int pageSize){ fr`Q
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this.pageSize = pageSize; gv){&=9/
} _&r19pY
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publicint getTotalCount(){ W
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return totalCount; n%7?G=_kj
} F. SB_S<'
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publicvoid setTotalCount(int totalCount){ =oq8SL?bJ*
if(totalCount > 0){ %ERcFI]G
this.totalCount = totalCount; KaNs>[a8
int count = totalCount / XH$r(@Z\7
r_#dh
pageSize; i#`q<+/q
if(totalCount % pageSize > 0) Xi98:0<=
count++; ]2wxqglh)
indexes = newint[count]; hDW!pnj1
for(int i = 0; i < count; i++){ _Ns EeKU
indexes = pageSize * Ptv'.<-
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i; T"_'sSI>tF
} 7t:RQ`$:
}else{ 6`e7|ilh6
this.totalCount = 0; w31Ox1>s
} +y?Ilkk;j
} L>h8>JvQ
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publicint[] getIndexes(){ ]$@D=g,r
return indexes; sI!H=bp-8
} 'j6O2=1
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publicvoid setIndexes(int[] indexes){ kO}&Oi,?
this.indexes = indexes; I4X9RYB6c
} [8i)/5D4
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publicint getStartIndex(){ l}))vf=i
return startIndex; P2-&Im`+
} 6QX m]<
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publicvoid setStartIndex(int startIndex){ ,twx4r^
if(totalCount <= 0) :CyHo6o9
this.startIndex = 0; {arqcILr
elseif(startIndex >= totalCount) ZD]1C~)
this.startIndex = indexes "La;$7ds
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[indexes.length - 1]; f<Hi=Qpm
elseif(startIndex < 0) YA4 D?'
this.startIndex = 0; *j%x
else{ mH'~pR>t
this.startIndex = indexes 8b2 =n
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[startIndex / pageSize]; <-umeY"n>
} Wh)D_
} d#g))f;
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publicint getNextIndex(){ 7Q}pKq]P
int nextIndex = getStartIndex() + M3pE$KT0x
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pageSize; pjWRd_h.
if(nextIndex >= totalCount) Yq+1kA
return getStartIndex(); Y^eN}@]?&
else x#>V50E
return nextIndex; _v,0"_"
} h Jb2y`,q
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publicint getPreviousIndex(){ 7zb^Z]
int previousIndex = getStartIndex() - i}) s4%a
}e?H(nZS7h
pageSize; /<J(\;Jr6
if(previousIndex < 0) 4ba*Nc*Yc
return0; HZyA\FS
else oN7SmP_
return previousIndex; Z}J5sifr
} 513,k$7
z0[XI 7KK
} O
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抽象业务类 G,u=ngZ]
java代码: R6+)&:Ab{R
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/** +[7~:e}DZ
* Created on 2005-7-12 :GXF=Df
*/ D|:'|7l W
package com.javaeye.common.business; u "[f\l
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import java.io.Serializable; i9;
import java.util.List; x[(6V'
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import org.hibernate.Criteria; PsC")JS
import org.hibernate.HibernateException; p}1i[//S
import org.hibernate.Session; p['RV
import org.hibernate.criterion.DetachedCriteria; RY , <*
import org.hibernate.criterion.Projections; .H" ?&Mf
import AUnfhk@$
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org.springframework.orm.hibernate3.HibernateCallback; [C'bfX5HB5
import n|( lPbD
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org.springframework.orm.hibernate3.support.HibernateDaoS jm}CrqU
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upport; Ipp_}tl_
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import com.javaeye.common.util.PaginationSupport; ON :t"z5
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public abstract class AbstractManager extends \T7Mt|f:5
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HibernateDaoSupport { Y6` xb`
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privateboolean cacheQueries = false; k# [!; <
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privateString queryCacheRegion; tW\yt~q,
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>
publicvoid setCacheQueries(boolean w'S,{GW
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cacheQueries){ LOh2eZ"n
this.cacheQueries = cacheQueries; M<vPE4TIr*
} SyWZOE%p
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publicvoid setQueryCacheRegion(String Vao:9~
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queryCacheRegion){ |5&+VI
this.queryCacheRegion = GEc6;uz<
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queryCacheRegion; lSxb:$g
} VoU8I ~
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publicvoid save(finalObject entity){ pSs*Z6c)@
getHibernateTemplate().save(entity); pgU[di
} V;M_Y$`Lh
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publicvoid persist(finalObject entity){ O'<V[Y}6
getHibernateTemplate().save(entity); O)'CU1vMb
} )(iv#;ByL
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publicvoid update(finalObject entity){ W }NUU
getHibernateTemplate().update(entity); {{G)Ry*pb
} H>~ CL
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publicvoid delete(finalObject entity){ %yR XOt2(
getHibernateTemplate().delete(entity); "Xq_N4
} }w0pi
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publicObject load(finalClass entity, kSAVFzUS
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finalSerializable id){ D6"=2XR4n
return getHibernateTemplate().load -l^<[%
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(entity, id); !~ox;I}S
} >3 o4 U2
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publicObject get(finalClass entity, djd/QAfSC
)U/jD
finalSerializable id){ R9J!}az'
return getHibernateTemplate().get ZpTDM1ro
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(entity, id); ?CpVA
} F/5&:e?( )
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publicList findAll(finalClass entity){ Y|Iq~Qy~
return getHibernateTemplate().find("from ]aX@(3G1s
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" + entity.getName()); c*bvZC^6
} je] DR~
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publicList findByNamedQuery(finalString I"Oq< _
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namedQuery){ x#1Fi$.
return getHibernateTemplate c~ss^[qx|
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().findByNamedQuery(namedQuery); %OQdUH4x
} X9x`i
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publicList findByNamedQuery(finalString query, D,#UJPyg
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finalObject parameter){ ,i>`Urd
return getHibernateTemplate Bf{u:TCK
7;>|9k
().findByNamedQuery(query, parameter); q lc@$
} !eX0Q 2
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publicList findByNamedQuery(finalString query, GVY7`k"km
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finalObject[] parameters){ 6v`3/o
return getHibernateTemplate GZ%vFje_
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().findByNamedQuery(query, parameters); V_7\VKR
} P9v(5Z00|d
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publicList find(finalString query){ }b_Ob
return getHibernateTemplate().find #QNN;&L]R
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(query); dN8Mfa)
} Q}BMvR 9w
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publicList find(finalString query, finalObject VAPeMO
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(W1$+X
parameter){ ">V1II
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return getHibernateTemplate().find >|f"EK}m!
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(query, parameter); fO<40!%9cQ
} gOF^?M11x
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public PaginationSupport findPageByCriteria 7=-Yxt
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(final DetachedCriteria detachedCriteria){ g=Xf&}&=x
return findPageByCriteria ~\":o:qyc
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3?Pg
;
} mjeJoMvN)H
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public PaginationSupport findPageByCriteria #g{R+#fm
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(final DetachedCriteria detachedCriteria, finalint VD=H=Ju
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startIndex){ mixsJ}e
return findPageByCriteria JP#S/kJ%3
*X0>Ru[
(detachedCriteria, PaginationSupport.PAGESIZE, | {9<%Ok4P
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startIndex); #p}GWS)
} O}M-6!%<,
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public PaginationSupport findPageByCriteria 4@9Pd &I
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(final DetachedCriteria detachedCriteria, finalint [.#nM
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$
pageSize, 'D\X$^J^
finalint startIndex){ ,s8/6n#
return(PaginationSupport) +_GS@)L`%
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getHibernateTemplate().execute(new HibernateCallback(){ *.W3V;K
publicObject doInHibernate -.Wcz|
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(Session session)throws HibernateException { D<WnPLA$g
Criteria criteria = :[0 R F^2}
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detachedCriteria.getExecutableCriteria(session); Pn,I^Ej .
int totalCount = <KMCNCU\+
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((Integer) criteria.setProjection(Projections.rowCount \<{a=@_k9
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()).uniqueResult()).intValue(); 3FBL CD3
criteria.setProjection !se1W5ke#
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(null); '=dQ$fs
List items = h;V4|jM
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criteria.setFirstResult(startIndex).setMaxResults (`(D
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(pageSize).list(); D$l!lRu8+L
PaginationSupport ps = sq|\!T
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new PaginationSupport(items, totalCount, pageSize, 4=Th<,<
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startIndex); =B}IsBn'J
return ps; ng}C$d . I
} K_YrdA)6
}, true); 9$)&b\D
} JL M Xkcc
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public List findAllByCriteria(final jQ{ @ol}n
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DetachedCriteria detachedCriteria){ q T6y&
return(List) getHibernateTemplate "OLg2O^
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().execute(new HibernateCallback(){ &5W;E+Pub
publicObject doInHibernate M@[W"f
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(Session session)throws HibernateException { Ci`o;KVj
Criteria criteria = DNGyEC
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detachedCriteria.getExecutableCriteria(session); ,L& yKS@
return criteria.list(); Ohm{m^VD"
} | 6{JINW
}, true); {H)7K.hQN
} >7W)iwF
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public int getCountByCriteria(final $hm[x$$
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DetachedCriteria detachedCriteria){ n]g"H
Integer count = (Integer) $8\u
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getHibernateTemplate().execute(new HibernateCallback(){ vl:~&I&y;R
publicObject doInHibernate 9]eG|LFD
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(Session session)throws HibernateException { 9&sb,^4
Criteria criteria = 0YiTv;mq;
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detachedCriteria.getExecutableCriteria(session); ;EBKzB
return {o~TbnC
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criteria.setProjection(Projections.rowCount _=HaE&
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()).uniqueResult(); 3Q,&D'];[
} k8?._1t
}, true); z"f@iJX?2
return count.intValue(); U'=8:&
} 7r;16"
} J4+K)gWB
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用户在web层构造查询条件detachedCriteria,和可选的 ?^U? ua6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 L6h<B
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PaginationSupport的实例ps。 @&?(XY 'M%
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ps.getItems()得到已分页好的结果集 .jJD$FC
ps.getIndexes()得到分页索引的数组 .57p4{
ps.getTotalCount()得到总结果数 )K[\j?
ps.getStartIndex()当前分页索引 [xiqlb,8
ps.getNextIndex()下一页索引 ,#2~<
ps.getPreviousIndex()上一页索引 3)WfBvG
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3CD#OCz7&
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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 Erw1y,mF
sFM$O232
一下代码重构了。 &|x7T<,)
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我把原本我的做法也提供出来供大家讨论吧: cF
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首先,为了实现分页查询,我封装了一个Page类: Mp/l*"(
java代码: X,G<D}
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/*Created on 2005-4-14*/ uXc;!*
package org.flyware.util.page; ]In7%Qb
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/** KO" /
* @author Joa R=~%kt_n
* y"yo\IDW
*/ 1)k+v17]f5
publicclass Page { m[eqTh4*
-6+7&.A+
/** imply if the page has previous page */ ah*{NR)
privateboolean hasPrePage; $z[S0C m
+(2$YJ35
/** imply if the page has next page */ 'i%r
privateboolean hasNextPage; OjhX:{"59
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/** the number of every page */ ^i|R6oO_5
privateint everyPage; %W~w\mT
SVo ?o|<
/** the total page number */ x/?ET1iGt
privateint totalPage; 36Lkcda[
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/** the number of current page */ ~vA{I%z5~
privateint currentPage; !S=YM<A d
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/** the begin index of the records by the current &%rM|
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query */ wF`Y
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privateint beginIndex; |RL#BKC`
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/** The default constructor */ sQ`G'<!
public Page(){ 6C
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} jRjeL'"G
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/** construct the page by everyPage RiQ]AsTtl
* @param everyPage (6$P/k8
* */ 6C2~0b
public Page(int everyPage){ ]JkEf?;.
this.everyPage = everyPage; u{DEOhtI4
} }`gOfj)?i
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/** The whole constructor */ K.xABKPVc
public Page(boolean hasPrePage, boolean hasNextPage, y.lWyH9
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int everyPage, int totalPage, "jAd.x?X7e
int currentPage, int beginIndex){ bg Ux&3
this.hasPrePage = hasPrePage; $A?9U}V#^
this.hasNextPage = hasNextPage; ,jRAVt+{N
this.everyPage = everyPage; nsI+04[F
this.totalPage = totalPage; Mw0>p5+ cy
this.currentPage = currentPage; o*)Sg6Yk
this.beginIndex = beginIndex; y nmjIQ
} -
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/** [uU!\xe
* @return AY5iTbL1
* Returns the beginIndex. Y5tyFi#w[
*/ ai-s9r'MI?
publicint getBeginIndex(){ 7}VqXUwabx
return beginIndex; 3`cA!ZVQ
} GCJ[x n(_
srf}+>u&
/** u0L-xC$L
* @param beginIndex YTa
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* The beginIndex to set. Wa|V~PL+T
*/ d9$RmCHe}
publicvoid setBeginIndex(int beginIndex){ J[<Zy^"Y;
this.beginIndex = beginIndex; jTR?!Mt0
} D#LV&4e>.E
YJv$,Z&;HO
/** {]+t<
* @return Sy VGm@
* Returns the currentPage. Wu{=QjgY
*/ eMRH*MyD
publicint getCurrentPage(){ B`mJT*B[
return currentPage; U|3!ixk>>w
} Nhs!_-_I
dLp1l2h!0
/** C=+9XfP 0
* @param currentPage ]zlA<w8
* The currentPage to set. hiS|&5#
*/ E@ :9|5
publicvoid setCurrentPage(int currentPage){ L"&T3i
this.currentPage = currentPage; Z8v 8@Y
} _P.I+!w:x
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/** o^/
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* @return \o!3TK"N
* Returns the everyPage. [@Ac#
*/ w6s[|i)&
publicint getEveryPage(){ J.yM@wPS>
return everyPage; w1G(s$;C
} T2Yf7Szp
4Et(3[P71
/** [1vm~w'
* @param everyPage g.&B8e
* The everyPage to set. Q!P%duO
*/ 6axxyh%
publicvoid setEveryPage(int everyPage){ \!\:p/f
this.everyPage = everyPage; 0 SSdp<
} b11I$b
#
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/** vR\E;V
* @return w||t3!M+n
* Returns the hasNextPage. OV]xo8a;
*/ <gwRE{6U
publicboolean getHasNextPage(){ Q|)>9m!tt
return hasNextPage; %NQ%6B
} ,LA'^I?
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/** `a&L
* @param hasNextPage <2)AbI+3
* The hasNextPage to set. 2G~{x7/[@
*/ |3FI\F;^q
publicvoid setHasNextPage(boolean hasNextPage){ 9F807G\4Qt
this.hasNextPage = hasNextPage; 4fKvB@O@.
} 9;L 4\
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/** ^i8,9T'=
* @return @SD XJJh
* Returns the hasPrePage. Leb
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*/ 1)=
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publicboolean getHasPrePage(){ y8$3kXh
return hasPrePage; |1%%c
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} ?1ey$SSU]
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/** futYMoV
* @param hasPrePage %AO6=
* The hasPrePage to set. 9&*
7+!
*/ E,m|E]WP
publicvoid setHasPrePage(boolean hasPrePage){ pX_
this.hasPrePage = hasPrePage; Dd1k?
} <~dfp
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/**
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* @return Returns the totalPage. iAH,f5T
* [k$GUU,jY
*/ :XY%@n
publicint getTotalPage(){ ~Fb@E0 }!
return totalPage; |X=p`iz1&
} rpiuFst
QKP
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/** yc*cT%?g
* @param totalPage 9CS"s_
* The totalPage to set. *B3f ry
*/ ?c?@j}=?yY
publicvoid setTotalPage(int totalPage){ qR.FjQOvn
this.totalPage = totalPage; C?|sQcCE
} C)U4Fr ?E:
M1eh4IVE?
} sR/Yv
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.8QhJHwd
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fR[8O\U~
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 J~KO#`
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个PageUtil,负责对Page对象进行构造: JAHg_!
java代码: 2e\"?y OD
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/*Created on 2005-4-14*/ Tp-W/YC
package org.flyware.util.page; ,C6(
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import org.apache.commons.logging.Log; +}m`$B}mJ
import org.apache.commons.logging.LogFactory; <9&GOaJ
h1q3}-
/** P.>fkO1\
* @author Joa -F/)-s6#!'
* FZgf"XM>
*/ Zw)=Y.y!
publicclass PageUtil { )vq}$W!:9
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privatestaticfinal Log logger = LogFactory.getLog _kBmKE
U)'YR$2<
(PageUtil.class); R>"pJbS;L
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/** (tA[] ne2
* Use the origin page to create a new page +On2R&m
* @param page imADjBR]
* @param totalRecords 1CJ1-]S(3
* @return pzRVX8
*/ jy~hLEt7
publicstatic Page createPage(Page page, int NCg("n,jx
2XyyU}.$
totalRecords){ >0SG]er@
return createPage(page.getEveryPage(), |34k;l]E
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page.getCurrentPage(), totalRecords); |m\7/&@<
} "
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c*#$sZ@YA
/** d0T 8Cwcb
* the basic page utils not including exception . ?#Q(eLj
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handler L__{U_p
* @param everyPage -5e8m4*
* @param currentPage L2Cb/!z`c
* @param totalRecords 0>m$e(Z
* @return page al Rz@N
*/ R[j'<gd.
publicstatic Page createPage(int everyPage, int ;ZJ. 7t'
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currentPage, int totalRecords){ ,^CG\);
everyPage = getEveryPage(everyPage); @[FO;4w
currentPage = getCurrentPage(currentPage); !gyW15z'
int beginIndex = getBeginIndex(everyPage, '~yxu$aK
z*VK{O)o
currentPage); 6GAEQ]
int totalPage = getTotalPage(everyPage, Y, Lpv|
_$A?
totalRecords); y z3=#
boolean hasNextPage = hasNextPage(currentPage, ^VzhjKSu
w?_'sP{pd
totalPage); fvta<
boolean hasPrePage = hasPrePage(currentPage); }x6)}sz7
"w 4^i!\
returnnew Page(hasPrePage, hasNextPage, LTx,oa:ma
everyPage, totalPage, @}^VA9ULK
currentPage, ~d<&OL
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beginIndex); Jl\U~i
} 0f_`;{
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privatestaticint getEveryPage(int everyPage){ .5SYN-@
return everyPage == 0 ? 10 : everyPage; @(6P L^I
} iqoMQ7%
v"Bm4+c&0
privatestaticint getCurrentPage(int currentPage){ ?Z!R
return currentPage == 0 ? 1 : currentPage; |pknaz
} ^[I>#U
yz>S($u
privatestaticint getBeginIndex(int everyPage, int 1.,KN:qe
t\:=|t,
currentPage){ r0f&n;0U4
return(currentPage - 1) * everyPage; +i /4G.=*
} w$]wd`N}
A]%*ye"NT
privatestaticint getTotalPage(int everyPage, int PXl%"O%d
Q4Wz5n1yp7
totalRecords){ sWTa;Qi
int totalPage = 0; 6%9 kc+
9
Rc93Fb-Zp
if(totalRecords % everyPage == 0) u>] )q7s
totalPage = totalRecords / everyPage; RHd no C
else Qo]qs+
totalPage = totalRecords / everyPage + 1 ; Dm?:j9o]g
d=\TC'd"{
return totalPage; :rk6Stn$z
} !gsrPM
^!O!HMX0
privatestaticboolean hasPrePage(int currentPage){ a&kt!%p:
return currentPage == 1 ? false : true; @}r
s6 G
} Nw,|4S
<}xgp[O
privatestaticboolean hasNextPage(int currentPage, qs8^qn0A
ifl
LY7j
int totalPage){ dBM{]@bZ
return currentPage == totalPage || totalPage == ^;{uop"DS
{a2Gb
0 ? false : true; 3*?W2;Zw$
} ~USyN'5lU7
`.~*pT*u
zDm3$P=
} K4RQ{fWpm
00>knCe6
aU.!+e%_
EpT^r8I
8B "^}y\0
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 &\ad.O/Q
@tRDKPh
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 svt3gkR0
Oku7&L1
做法如下: ww+,GnV
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 A&ceuu
sw:a(o&$
的信息,和一个结果集List: m.gv?
java代码: SpIiMu(
|g!$TUS.
FLG{1dS
/*Created on 2005-6-13*/ 0=9$k
package com.adt.bo; q&:%/?)x
McbbEs=)
import java.util.List; [1Qg *
+'w6=qI
import org.flyware.util.page.Page; !4z vkJO
4kK_S.&
/** V~-tp^
* @author Joa ^%\MOjSN
*/ R9K~b^`
publicclass Result { Y!ypG-
2PNe~9)*#
private Page page; 4,=;:#n,J
ZBQ @S
private List content; 1bDXv,nD
>C5u>@%9O
/** k|jr+hmn":
* The default constructor tQ.H/;
*/ v@fy*T\3
public Result(){ cQ`0d3
super(); s?Gv/&
} T;,,!
c:B` <
/** I,Jb_)H&t
* The constructor using fields HqyAo]{GN
* zW`a]n.
* @param page SC3_S.
* @param content d<m.5ECC}
*/ 4~;M\h
public Result(Page page, List content){ d\c)cgh%
this.page = page; q}z`Z/`/
this.content = content; rodqa
} IF6-VFY:6
:+?rnb)N
/** 93,7yZ5#
* @return Returns the content. q(2ZJn13f
*/ d+
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publicList getContent(){ ZC^NhgX
return content; PH^Gjm
} d*U<Ww^q
Ue>{n{H"y
/** #D ]CuSi
* @return Returns the page. ,.|/B^jV
*/ Q/h-Khmz
public Page getPage(){ +A$>F@u
return page; *q[;-E(fZ#
} eq<!
.Ep&O#
/** >V\^oh)t]t
* @param content |GP&!]
* The content to set. 5-&"nn2*}1
*/ b0x%#trA{
public void setContent(List content){ R.
vVl+
this.content = content; PY+4OZ$
} Qf'g2
\
)NqRu+j
/** 8NJT:6Q7l
* @param page [1z.JfC :S
* The page to set. :"@-Bcln
*/ 8L6b:$Y3@C
publicvoid setPage(Page page){ kN#3HI]8
this.page = page; 5;HCNwX
} $Fy>N>,E(
} eYu 0")
:s-9@Yl|
&$l#0?Kc^
mwI7[I2q
uaky2SgN
2. 编写业务逻辑接口,并实现它(UserManager, dI!/H&`B]
>Ml5QO$*.q
UserManagerImpl) *{\))Zmhd
java代码: _qo\E=E
i1bmUKZ8'L
#ZP;] W
/*Created on 2005-7-15*/ |WOc0M[U
package com.adt.service; cF?0=un
)V_;]9<wt
import net.sf.hibernate.HibernateException; B$hog_=s
<num!@2D
import org.flyware.util.page.Page; nI1(2a1
[%~yY&
import com.adt.bo.Result; 2. {/ls
q[/pE7FL
/** !DF5NAE
* @author Joa 'P[#.9E
*/ j"VDqDDz
publicinterface UserManager { $2-_j)+
S.<4t*,
public Result listUser(Page page)throws wTG(U3{3K
O}}rosA
HibernateException; qL[SwEc
Mq'm
TM
} l@-h.tS
(=EDqAZg
>vO+k^'Y
JZ&_1~Z=
aeAx0yE[p
java代码: )8SWU)/
<$WS~tTz
dep"$pys>
/*Created on 2005-7-15*/ j0(jXAc;UB
package com.adt.service.impl; J(wFJg\/
!+QfQghAT
import java.util.List; k]`-Y E
M.:JT31>1
import net.sf.hibernate.HibernateException; KeXt"U
n1:q:qMR1
import org.flyware.util.page.Page; _aJKt3GQ
import org.flyware.util.page.PageUtil; ~l*<LXp8
x($Djx
import com.adt.bo.Result; $J&c1
import com.adt.dao.UserDAO; Fmz+ Xb
import com.adt.exception.ObjectNotFoundException; 5K)_w:U
X
import com.adt.service.UserManager; /H3w7QU
Ndgx@LTQQ
/** U=U5EdN;
* @author Joa AYpvGl'
*/ (oG.A
publicclass UserManagerImpl implements UserManager { j-DWz>x
tV>qV\>
private UserDAO userDAO; Uqy/~n-v<
e0otr_)3F
/** %~PT7"4
* @param userDAO The userDAO to set. %H,s~IU
*/ D{[{ &1\)r
publicvoid setUserDAO(UserDAO userDAO){ l=((>^i
this.userDAO = userDAO; ek0!~v<I
}
5C^@w
I3d}DpPx%
/* (non-Javadoc) JY^i
* @see com.adt.service.UserManager#listUser Dg{d^>T!_x
N^@:+,<3
(org.flyware.util.page.Page) ;[(d=6{hc]
*/ sf->8
public Result listUser(Page page)throws Bx#=$ka
_{gqi$Mi
HibernateException, ObjectNotFoundException { 2gMG7%d
int totalRecords = userDAO.getUserCount(); GNq
f
if(totalRecords == 0) bovAFdHW
throw new ObjectNotFoundException L[,19;(
u]9\_{c]Q
("userNotExist"); sowwXrECg@
page = PageUtil.createPage(page, totalRecords); qMA-#
List users = userDAO.getUserByPage(page); Au}l^&,zN
returnnew Result(page, users); +oq<}CNr{
} x;\/Xj;
F"O\uo:3
} eF9GhwE=
b78~{ht`
IF\ @uo`
2lOUNx Q$
=WBfaxL}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 bv b\G
1 <+aF,
询,接下来编写UserDAO的代码: vv{+p(~**O
3. UserDAO 和 UserDAOImpl: 4KnBb_w
java代码: X;Sb^c"j1
x&0kIF'lq
f.+1Ubq!5
/*Created on 2005-7-15*/ +A)>
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package com.adt.dao; V[K N,o{6
pt,L
import java.util.List; a !%,2|U
;l
ZKgi8`
import org.flyware.util.page.Page; Fb=uN
|?8nO.C~V
import net.sf.hibernate.HibernateException; DL1nD5
!4'F z[RK
/** !2l2;?jM
* @author Joa T,1qR:58
*/ +>K&zS
publicinterface UserDAO extends BaseDAO { i/1$uQ
>7%T%2N
publicList getUserByName(String name)throws yNP4Ey
V-n{=8s
HibernateException; zqXF`MAB=
m m`#v
g,
publicint getUserCount()throws HibernateException; \AKP ea=
j-W$)c3X
publicList getUserByPage(Page page)throws `Hlf.>b1
dnU-v7k,{
HibernateException; J:Qx5;b;
/Xb4'Qj
} }&e HU
C49\'1\6
X.k8w\~
V<jj'dZfW
J&,hC%]
java代码: H>+])~#
fe98Y-e
HbsNF~;
/*Created on 2005-7-15*/ X )tH23
package com.adt.dao.impl; h72/03!
V3q`V/\
import java.util.List; aaT3-][
cK u[4D{
import org.flyware.util.page.Page; k'#3fz\
iC=>wrqY>
import net.sf.hibernate.HibernateException; MyllL@kP
import net.sf.hibernate.Query; Hy&Z0W'l
@:GqOTN
import com.adt.dao.UserDAO; x]x 3iFD
L'?aoRj
/** 4oiE@y&{4
* @author Joa `cXLa=B)9
*/ >RkaFcq
public class UserDAOImpl extends BaseDAOHibernateImpl 8X"4RyNSn
": M]3.
implements UserDAO { pF-_yyQ
sIgTSdk
/* (non-Javadoc) ]B=*p0~j^n
* @see com.adt.dao.UserDAO#getUserByName T:X*
O& Sk}^
(java.lang.String) aq}hlA(w
*/ d4;$=P
publicList getUserByName(String name)throws QhJN/v
vxEi C:&]
HibernateException { Mh-"B([Z
String querySentence = "FROM user in class Sl,DZ!
ocZ}RI#Q
com.adt.po.User WHERE user.name=:name"; ?%hd3zc+f
Query query = getSession().createQuery ^]R_t@
yVmp,""a
(querySentence); aO&{.DO2
query.setParameter("name", name); A_wf_.l4h
return query.list(); Yz_}*
} KYm8|]'g
s0f+AS|}
/* (non-Javadoc) )__sw
* @see com.adt.dao.UserDAO#getUserCount() l!88|~
*/ u0&R*YV
publicint getUserCount()throws HibernateException { 9d#?,:JG
int count = 0; Xpg-rxX
String querySentence = "SELECT count(*) FROM .eD&UQ
jsE8=zZs
user in class com.adt.po.User"; zP #:Tv'
Query query = getSession().createQuery B]G2P`sN
]A%3\)r
(querySentence); 0j!3\=P$
count = ((Integer)query.iterate().next NeY*l
qm!oJL
()).intValue(); V=8db%^
return count; K
$- *
} g]?pY
zl:by?
/* (non-Javadoc) 6LCtWX
* @see com.adt.dao.UserDAO#getUserByPage p7Wt(A
M> WWP3
(org.flyware.util.page.Page) )Y)_T&O
*/ q=5aHH% |
publicList getUserByPage(Page page)throws +\Jo^\
it\$Pih]
HibernateException { `D[O\ VE
String querySentence = "FROM user in class IdAh)#)
7
yO%^[c?
com.adt.po.User"; ?m]vk|>
Query query = getSession().createQuery Dnw^H.
{. 9BG&
(querySentence); auK9wQ%\
query.setFirstResult(page.getBeginIndex()) by
@q g:
.setMaxResults(page.getEveryPage()); @iuX~QA[9
return query.list(); :k1?I'q%
} -#f.}H'
)v_Wn[Y.H
} T"vf
7wx=#
cmXbkM
VU,G.eLW
#wIWh^^ Zy
至此,一个完整的分页程序完成。前台的只需要调用 u>lt}0
3 k/E$wOj
userManager.listUser(page)即可得到一个Page对象和结果集对象 \[3~*eX6
h6D4CT
的综合体,而传入的参数page对象则可以由前台传入,如果用 )mm0PJF~q
yor'"6)i
webwork,甚至可以直接在配置文件中指定。 <jV,VKL#
QNx]8r
下面给出一个webwork调用示例: }qECpKa0
java代码: RQ8d1US
Nq`;\E.M
qG;tD>jy
/*Created on 2005-6-17*/ ZcXAqep8'
package com.adt.action.user; ,:(s=JN+
C;m"W5+
import java.util.List; H^n@9U;[K
C5dM`_3L
import org.apache.commons.logging.Log; c%pf,sm'
import org.apache.commons.logging.LogFactory; $~FZJ@qa
import org.flyware.util.page.Page; Hj{.{V
8*0QVFn$
import com.adt.bo.Result; Bp7p X
import com.adt.service.UserService; Li5&^RAo|J
import com.opensymphony.xwork.Action; xS1n,gTA
USyc D`
/** )v;O2z
* @author Joa B=d<L^
*/ I+kAy;2
publicclass ListUser implementsAction{ 6o#/[Tz
{OPEW`F
privatestaticfinal Log logger = LogFactory.getLog B3ItZojAuw
V>QyiB
(ListUser.class); 9{;L7`<
@h|qL-:!vG
private UserService userService; L/:l>Ko>7
}X{rE|@
private Page page; %J-0%-/_S:
3F|p8zPS
privateList users; >M2~p&Si
pL{oVk#,
/* Vhv'Z\
* (non-Javadoc) Qz|T0\=V
* ~7ZZb*].(
* @see com.opensymphony.xwork.Action#execute() _|M8xI
*/ \o[][R#D
publicString execute()throwsException{ c_vGr55
Result result = userService.listUser(page); ,A` |jF
page = result.getPage(); EF
:g0$
users = result.getContent(); !j'LZ7
return SUCCESS; 9Q,>I6`l
} }
KyoMs
?]D&D:Z?I
/** z9S
(<