Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 mFuHZ)iQG
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "'I|#dKoG
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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 +)*oPSQ5
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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 eOUEhpE
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分页支持类: E*#5OT
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java代码: ~PedR=Y0n
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package com.javaeye.common.util; J L2g!n=
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import java.util.List; rTA#4.*&
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publicclass PaginationSupport { qGECw#
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publicfinalstaticint PAGESIZE = 30; S1_):JvV
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privateint pageSize = PAGESIZE; 3q0S}<h al
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privateList items; U{8x.CJ]
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privateint totalCount; )xYGJq4
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privateint[] indexes = newint[0]; &B} ,xcNO
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privateint startIndex = 0; Qa,$_,E
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public PaginationSupport(List items, int vk|xYDD
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totalCount){ (Cbm*VL
setPageSize(PAGESIZE); \m~Oaf;$
setTotalCount(totalCount); <d$t*vnq
setItems(items); C&RZdh,$
setStartIndex(0); pw=o}-P{
} O`0\f8/.?
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public PaginationSupport(List items, int uB+:sX-L
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totalCount, int startIndex){ NnO%D^P]
setPageSize(PAGESIZE); n<DZb`/uHZ
setTotalCount(totalCount); .N Z
setItems(items); GBGna3
setStartIndex(startIndex); r5PZ=+F
} *~8g:;u
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public PaginationSupport(List items, int \!Ap<
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totalCount, int pageSize, int startIndex){ J''lOj(@
setPageSize(pageSize); \NQ[w7
setTotalCount(totalCount); kQO5sX$;
setItems(items); QzV%m0
setStartIndex(startIndex); ZEG~ek=jM
} hGU 3DKHT
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publicList getItems(){ SBamgc
return items; :hDv^D?3
} 71,GrUV:
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publicvoid setItems(List items){ ;!#IRR
this.items = items; X-cP'"
} `/o| 1vv@_
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publicint getPageSize(){ M8f[ ck
return pageSize; \};
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} t7,** $ST
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publicvoid setPageSize(int pageSize){ 8,]wOxwqi
this.pageSize = pageSize; FOS*X
} /7K7o8g
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publicint getTotalCount(){ G Cp90
return totalCount; e}2[g
} 8D`TN8[W
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publicvoid setTotalCount(int totalCount){ a!;CY1>
if(totalCount > 0){ ez[$;>
this.totalCount = totalCount; mN'sJ1L-
int count = totalCount / 8j8~?=$a6Q
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pageSize; MO
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if(totalCount % pageSize > 0) NX?6
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count++; dXDuO
indexes = newint[count]; ^'4I%L"
for(int i = 0; i < count; i++){ d@{#F"o
indexes = pageSize * cp4~`X
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i; b:x*Hjf
} r9~I R
}else{ ,~XAV ;+
this.totalCount = 0; Mqm9i
} gg$:U
} j/hm)*\io
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publicint[] getIndexes(){ /X?%K't2r
return indexes; ^*WO*f>y
} gX/?
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publicvoid setIndexes(int[] indexes){ >&)|fV&4
this.indexes = indexes; g7Z3GUCGL
} Hx ojxZwm
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publicint getStartIndex(){ ?nD]p!
return startIndex; dSbz$Fc t
} sUpSXG-W/@
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publicvoid setStartIndex(int startIndex){ ~oeX0l>F
if(totalCount <= 0) 6tup^Rlo;$
this.startIndex = 0; #x(3>}
elseif(startIndex >= totalCount) ]9hhAT44
this.startIndex = indexes /rv=mlpRL
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[indexes.length - 1]; 'HvJ]}p
elseif(startIndex < 0) GX%r-
this.startIndex = 0; &M2fcw?
else{ $K_-I8e|
this.startIndex = indexes VQn]"G(`
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[startIndex / pageSize]; 36yIfC,
} FK;2u$:
} !FeNx*31i
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publicint getNextIndex(){ 9+:<RFJ
int nextIndex = getStartIndex() + M|qJZ#{4>
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pageSize; Z xR
if(nextIndex >= totalCount) Qz([\Xx:
return getStartIndex(); ;%O>=m'4
else ='<*mT<
return nextIndex; Z%7X" w
} -m Sf`1l0
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publicint getPreviousIndex(){ KwhATYWQb
int previousIndex = getStartIndex() - iLf*m~Q
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pageSize; `B7? F$J
if(previousIndex < 0) ZnD(RM
return0; i{k v$ir!
else 1f0maN
return previousIndex; %DhLU~VX
} tdn|mX#
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} }*56DX
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抽象业务类 9f$3{ g{m
java代码: {EVHkQ+o
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/** W";Po)YC
* Created on 2005-7-12 WRN}>]NgQ
*/ GD#W=O
package com.javaeye.common.business; `qa>6`\
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import java.io.Serializable; >RKepV(X7
import java.util.List; bdvVPjGc&
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import org.hibernate.Criteria; 0Y/k/)Ul]
import org.hibernate.HibernateException; ou[Wz{
import org.hibernate.Session; -d6PXf5
import org.hibernate.criterion.DetachedCriteria; ]0;,M
import org.hibernate.criterion.Projections; G3de<?K.[V
import eLk:">kj
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org.springframework.orm.hibernate3.HibernateCallback; vf['$um
import K2-nP2Go?
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org.springframework.orm.hibernate3.support.HibernateDaoS TXfG@4~kC
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upport; 5!7vD|6
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import com.javaeye.common.util.PaginationSupport; "IJcKoB
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public abstract class AbstractManager extends LH>h]OTQF
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HibernateDaoSupport { kI/%|L%6D
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privateboolean cacheQueries = false; <u2iXH5w
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privateString queryCacheRegion; Q&?B^[N*Q
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publicvoid setCacheQueries(boolean #oEq)Vq>g|
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cacheQueries){ Owm2/
this.cacheQueries = cacheQueries; n]bxG8~t
} [N1[khY`
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publicvoid setQueryCacheRegion(String *AA78G|
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queryCacheRegion){ +(vL~
this.queryCacheRegion = KPI[{T\`ZM
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queryCacheRegion; G>W:3y
} Q?-u J1J
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publicvoid save(finalObject entity){ 30L/-+r1
getHibernateTemplate().save(entity); |sV@j_TX
} juBzpQYj
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publicvoid persist(finalObject entity){ R5'_il
getHibernateTemplate().save(entity); k1M?6TW&
} t:qPW<wc
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publicvoid update(finalObject entity){ B-aJn8>/
getHibernateTemplate().update(entity); Axx{G~n! [
} a1A3uP
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publicvoid delete(finalObject entity){ {;?bC'
getHibernateTemplate().delete(entity); kl9<l*
} 1Yy*G-7}
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publicObject load(finalClass entity, Kw,ln<)2
}#9 |au`
finalSerializable id){ `pYL/[5
return getHibernateTemplate().load 3Tr}t.mt
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(entity, id); PoRL35
} M@O<b-
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publicObject get(finalClass entity, S3_QOL
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finalSerializable id){ 4L[-[{2
return getHibernateTemplate().get v@
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(entity, id); =s[P =d U
} {$^Lb4O[V
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publicList findAll(finalClass entity){ ?[S{kMb2
return getHibernateTemplate().find("from DwH=ln=
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" + entity.getName()); >?0 f>I%\
} D_Cd^;b
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publicList findByNamedQuery(finalString nv"D
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namedQuery){ sK`pV8&xq
return getHibernateTemplate b:(*C
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().findByNamedQuery(namedQuery); S]&7
} ;gv9J[R
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publicList findByNamedQuery(finalString query, qf6}\0
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finalObject parameter){ Q5qQ%cu
return getHibernateTemplate Y([vma>U]
sBD\;\I
().findByNamedQuery(query, parameter); z3p#`
} '8bT9
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publicList findByNamedQuery(finalString query, D1<$]r,
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finalObject[] parameters){ Vch!&8xii
return getHibernateTemplate _ gi?GQj
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().findByNamedQuery(query, parameters); 9{V54ue;
} JIyIQg'5i
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publicList find(finalString query){ \m;"KyP+
return getHibernateTemplate().find xT1{O `
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(query); kVb8 $Sp
} 4>xv7
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publicList find(finalString query, finalObject 3RTraF
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parameter){ )0NE_AZ?
return getHibernateTemplate().find w/m~#`a
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(query, parameter); obhq2sK
} y1:#0
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public PaginationSupport findPageByCriteria Gd5J<K
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(final DetachedCriteria detachedCriteria){ ,:QDl
return findPageByCriteria H:HJHd"W
kf<5`8
(detachedCriteria, PaginationSupport.PAGESIZE, 0); "?Cx4<nsM
} Fv6<Cz6L
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public PaginationSupport findPageByCriteria I5J9,j
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(final DetachedCriteria detachedCriteria, finalint 2!35Tj"RFE
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startIndex){ @gZ<!g/vza
return findPageByCriteria 8Dq;QH}
c{u~=24;%#
(detachedCriteria, PaginationSupport.PAGESIZE, -a[]#v9
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startIndex); eY1$smh t
} Bld $<uU
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public PaginationSupport findPageByCriteria C +%&!Q
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ex
(final DetachedCriteria detachedCriteria, finalint .hxcx>%
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pageSize, 9s-op:5
finalint startIndex){ xED`8PCfu
return(PaginationSupport) -/.Xf<y58
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getHibernateTemplate().execute(new HibernateCallback(){ *kXSl73 k
publicObject doInHibernate :_q
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(Session session)throws HibernateException { oO4
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Criteria criteria = jy] hP?QG
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detachedCriteria.getExecutableCriteria(session); zOpl#%"
int totalCount = %7PprN0>
6.Nu[-?
((Integer) criteria.setProjection(Projections.rowCount >a;^=5E
h7-!q@
()).uniqueResult()).intValue(); .oq!Ys4KA
criteria.setProjection bqXCe\#
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(null); lGI5
List items = 6s833Tmb&r
7RmL#f`
criteria.setFirstResult(startIndex).setMaxResults av( d0E}}b
D@yg)$;z
(pageSize).list(); yWACIaj
PaginationSupport ps = eiJO;%fl>l
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new PaginationSupport(items, totalCount, pageSize, Oph4&Ip[w
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startIndex); Ek +L"7
return ps; -~A7o3k35
} ~EIY(^|py
}, true); &X
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} @+VvZc2Y
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public List findAllByCriteria(final x=yU
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DetachedCriteria detachedCriteria){ <_02)6j
return(List) getHibernateTemplate J<Wz3}w6
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().execute(new HibernateCallback(){ W>Y8 u8
publicObject doInHibernate K h9 $
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(Session session)throws HibernateException { 5#.uA_Fov
Criteria criteria = 2,O-/A;tW*
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detachedCriteria.getExecutableCriteria(session); (XJehdB0
return criteria.list(); ^lT$D8
} .*>LD
}, true); TR rO-
} ]<q{0.
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public int getCountByCriteria(final br}.s@~
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DetachedCriteria detachedCriteria){ )#MKOsOct
Integer count = (Integer) +15j^ Az
}$V]00
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getHibernateTemplate().execute(new HibernateCallback(){ v@;:aN
publicObject doInHibernate g/so3F%v
.
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(Session session)throws HibernateException { N~ljU;wo-9
Criteria criteria = ]DdD
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detachedCriteria.getExecutableCriteria(session); M|FwYF^
return r_]wa
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criteria.setProjection(Projections.rowCount $Vbgfp~U-
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()).uniqueResult(); ^LTLyt)/
} Kwfrh?
}, true); Z?[;Japg
return count.intValue(); 8[,,Kr)-
} "*#$$e53A
} q^Lj)zmnK
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用户在web层构造查询条件detachedCriteria,和可选的 `8\pihww
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Q5r cPU>A
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PaginationSupport的实例ps。 A2Rr*e
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ps.getItems()得到已分页好的结果集 ;7 i0ko9
ps.getIndexes()得到分页索引的数组 qDhz|a#
ps.getTotalCount()得到总结果数 5h+g^{BE
ps.getStartIndex()当前分页索引 ;%]Q%7
ps.getNextIndex()下一页索引 +KDB^{
ps.getPreviousIndex()上一页索引 t3 *2Z u
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 v(FO8*5DZ
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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 nO$(\
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一下代码重构了。 _,NL;66=[
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我把原本我的做法也提供出来供大家讨论吧: 5ts8o&|
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首先,为了实现分页查询,我封装了一个Page类: QSAz:Yvf|
java代码: so8isDC'9
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/*Created on 2005-4-14*/ |`U^+Nf
package org.flyware.util.page; t\CVL?e`
jWiB_8-6
/** b@Ik
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* @author Joa -mO[;lO
* iwJBhu0@#
*/ CP |N2rb
publicclass Page { "\vEi
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5sM-E>8G^{
/** imply if the page has previous page */ ' ,a'r.HJH
privateboolean hasPrePage; WsL*P.J
d&wg\"E
/** imply if the page has next page */ &rorBD 5aj
privateboolean hasNextPage; 7X2g"2\Wm
;q6:*H/
/** the number of every page */ 2l{g$44
privateint everyPage; "T<Q#^m
LP7t*}PK
/** the total page number */ C=h$8Q
privateint totalPage; Dsm_T1X
)j4]Y dJ
/** the number of current page */ %8yfFrk
privateint currentPage; KU"?ZI
y!1%Kqx1,n
/** the begin index of the records by the current l-XiQ#-{
{uL<$;#i
query */ :7e2O!zH_
privateint beginIndex; hc"+6xc
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/** The default constructor */ $s/N;E!t
public Page(){ 9-Ikd>9
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} 4G;+ETp
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/** construct the page by everyPage G=jdb@V/?
* @param everyPage WT;=K0W6&
* */ u!k\W{
public Page(int everyPage){ S3MMyS8
this.everyPage = everyPage; G{knO?BK
} zM|d9TS
tU}CRh
/** The whole constructor */ `D>PU@s$nT
public Page(boolean hasPrePage, boolean hasNextPage, bDeHU$
!Q*.Dw()[
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int everyPage, int totalPage, KR^lmN
int currentPage, int beginIndex){ r'7;:
this.hasPrePage = hasPrePage; q^JJ5{36e
this.hasNextPage = hasNextPage; {e/12q
this.everyPage = everyPage; n (C*LK
this.totalPage = totalPage; GLcf'$l
this.currentPage = currentPage; d?oupW}uu
this.beginIndex = beginIndex; ?NGM<nK;7
} [0lCb"
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/** lV?rC z
* @return - A
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* Returns the beginIndex. SJ6lI66OX
*/ 2Y(Phw2%
publicint getBeginIndex(){ ~x)Awdlu
return beginIndex; Ih ;6(5z
} `ihlKFX
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/** ua/A &XQx
* @param beginIndex qmdl:J|?
* The beginIndex to set. }9/30
*/ `l9Pk\X[
publicvoid setBeginIndex(int beginIndex){ s_hf,QH
this.beginIndex = beginIndex; 0F8y8s
} Dq)V] Zx
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/** vd|PTHV_
* @return R61.!ql%w
* Returns the currentPage. ctTg-J2.
*/ u_dTJ,m
publicint getCurrentPage(){ ZK[4 n5}
return currentPage; izebQVQO*
} azr|Fz/
>)R7*^m{'
/** UA!-YTh
* @param currentPage AY5%<CWj8
* The currentPage to set. .5 p"o-:D
*/ f>s3Q\+
publicvoid setCurrentPage(int currentPage){ !e?=I
this.currentPage = currentPage; "A~\$
} awB1ryrOF
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/** !>TVDN>
* @return 4`o_r%
* Returns the everyPage. 3!_y@sWx
*/ elG<\[
publicint getEveryPage(){ U ; JZN
return everyPage; +7U$qEG
} Yz us=
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/** +;c)GNQ)6:
* @param everyPage a}|B[b
* The everyPage to set. R+Dx#Wn I
*/ |>5NH'agV
publicvoid setEveryPage(int everyPage){ )'?3%$EM
this.everyPage = everyPage; iOkRB[hi
} e%uPZ >'q
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/** 8L`J](y
* @return ts`c_hH,1'
* Returns the hasNextPage. {f((x1{HZx
*/ gtHWd;1&f
publicboolean getHasNextPage(){ g,h'K
return hasNextPage; Wz)s#
} _Jx.?8
T?4MFx#
/** $ jWe!]ASU
* @param hasNextPage )cJ9YKKy
* The hasNextPage to set. zlco?Rt
*/ =3$JeNK9
publicvoid setHasNextPage(boolean hasNextPage){ Qh<_/X?
this.hasNextPage = hasNextPage; [G>8N5@*
} {'C PLJ{R
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/** "_WOtJr
* @return =+%QfuK
* Returns the hasPrePage. S@*lI2
*/ :V*c9,>ZO
publicboolean getHasPrePage(){ wa-#C,R\_#
return hasPrePage; i2j_=X-
} m^Qc9s#D
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/** 48vKUAzx`
* @param hasPrePage S+
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* The hasPrePage to set. )ZC0/>R
*/ BF{v0Z0/}k
publicvoid setHasPrePage(boolean hasPrePage){ FBJw (.Jr
this.hasPrePage = hasPrePage; ZjF5*A8l
} VRQ'sn@
[0<N[KZ)
/** T}d%X MXq
* @return Returns the totalPage. P&@ 2DI3m
* :l~Wt7R
*/ eLWD?-v%
publicint getTotalPage(){ }G}2Y (
return totalPage; %MGbIMpY
} >Vc;s!R
I!>pHF4
/** m<qPj"g~L
* @param totalPage M:K5r7Q!yv
* The totalPage to set. mj:X'BVA
*/ i,|2F9YH
publicvoid setTotalPage(int totalPage){ = i9|lU"Va
this.totalPage = totalPage; ,'w9@A
} ncZ5r0
Q{-T;T
} *gF8"0s
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 qM%l
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个PageUtil,负责对Page对象进行构造: x.W93e[]H
java代码: ;U$Fz~rJ
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/*Created on 2005-4-14*/ jyB^a;-
package org.flyware.util.page; 1 ? be
sg0HYb%_E
import org.apache.commons.logging.Log; 1@" L
import org.apache.commons.logging.LogFactory; :+Ti^FF`w
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/** H|@R+
* @author Joa )~@iM.}S2
* <E/"v
*/ 4FLL*LCNX
publicclass PageUtil { R;D|To!
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privatestaticfinal Log logger = LogFactory.getLog JSO'. [N
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(PageUtil.class); ~t0\Q; @($
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/** leY fF
* Use the origin page to create a new page lHl1Ny\?
* @param page ZDffR:An
* @param totalRecords /D@(o`a
* @return *Y"j 0Yob
*/ b@9>1d$
publicstatic Page createPage(Page page, int ~#
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totalRecords){ w&U>w@H^
return createPage(page.getEveryPage(), Dq$co1eT
@xu/&pbI
page.getCurrentPage(), totalRecords); b Ag>;e(
} ^j-w^)@T
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/** v7Q=
* the basic page utils not including exception f3bZ*G%f
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handler I{rW+<)QGC
* @param everyPage @20~R/vh
* @param currentPage 3d_PY,=1
* @param totalRecords g#Doed.30=
* @return page w26x)(7
*/ ~4MUac^w
publicstatic Page createPage(int everyPage, int Vy+UOV&v-
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currentPage, int totalRecords){ qYi<GI*|@
everyPage = getEveryPage(everyPage); k~P{Rm;F
currentPage = getCurrentPage(currentPage); h~F`[G/'
int beginIndex = getBeginIndex(everyPage, zc,kHO|
gJn_Z7Mg J
currentPage); fBZ\,
int totalPage = getTotalPage(everyPage, *CnrzrKtQ
\q |n0>
totalRecords); [>pqf
boolean hasNextPage = hasNextPage(currentPage,
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c[a1
Md&
totalPage);
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boolean hasPrePage = hasPrePage(currentPage); [u=DAk?8
4h[S`;D0Vf
returnnew Page(hasPrePage, hasNextPage, .W9/*cZV0
everyPage, totalPage, C6"bGA
currentPage, 1|PmZPKq9n
[;]@PKW?w
beginIndex); @|2}*_3\
} 1V@\L|Y
<;?&<qMo,P
privatestaticint getEveryPage(int everyPage){ [H3~b=
return everyPage == 0 ? 10 : everyPage; N$jI&SI?}
} _z3Hl?qk=
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privatestaticint getCurrentPage(int currentPage){ 7%(|)3"V
return currentPage == 0 ? 1 : currentPage; `Al[gG?/!
}
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fGv`.T _d
privatestaticint getBeginIndex(int everyPage, int E9Q?@' h
qwb`8o
currentPage){ LqHeLN
return(currentPage - 1) * everyPage; UJ0Dy` f
} FZ)Y<r8|s
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privatestaticint getTotalPage(int everyPage, int wFW2m
Wu
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totalRecords){ l;e&p${P
int totalPage = 0; LRhq%7p7
.2xp.i{
if(totalRecords % everyPage == 0) [xXml On!
totalPage = totalRecords / everyPage; YLlw:jN
else 6]|NB &
totalPage = totalRecords / everyPage + 1 ; 4LU'E%vlC
NRS!Ox
return totalPage; RRD\V3C84
} ]`D(/l'
ifu"e_^
privatestaticboolean hasPrePage(int currentPage){ Bx&.Tj
return currentPage == 1 ? false : true; Bc4{$sc"O
} ta+'*@V+G
i\S } aCm
privatestaticboolean hasNextPage(int currentPage, ?l_>rSly5
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int totalPage){ .P=uR8
return currentPage == totalPage || totalPage == }9=\#Le~\
o} #nf$v(
0 ? false : true; `d=$9Pi
} EX>|+zYL
[Cz.K?+#M
~Exd_c9
} KJa?TwnC
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7"f$;CN?~
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*@Z/L26s;=
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。 `4cs.ab
r'hr'wZ
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 #R|M(Z">q
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做法如下: Tk-PCra
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?lb1K'(
Gvt.m&_
的信息,和一个结果集List: *seKph+'c
java代码: KQ/v](77
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Y*``C):K%
/*Created on 2005-6-13*/ ,{c9Lv%@J
package com.adt.bo; #VC^><)3
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import java.util.List; 1fL@rR
FTt7o'U
import org.flyware.util.page.Page; DR9M8E
M[_~7~4
/** xIF
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* @author Joa rsfA.o
*/ K0]'v>AWr
publicclass Result { w\;=3C`
?ZSG4La\
private Page page; @Qx|!%
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private List content; -!MDYj +U
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/** @hm%0L
* The default constructor mW 5L;>
*/ w;'
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public Result(){ ;,'!
super(); kTex>1W;
} *6Rl[eXS
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/** MPO!qSS]
* The constructor using fields VzpPopD,QW
* V#!ypX]AB[
* @param page g_]
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* @param content n<CJx+U
*/ B>o\;) l3O
public Result(Page page, List content){ %kJ:{J+w]
this.page = page; yQhrPw> m
this.content = content; a-Cp"pKlVY
} PZpwi?N
S#+G?I3w
/** K4n1#]8i
* @return Returns the content. &tD`~
*/ ?9!tMRb
publicList getContent(){ N)
{
return content; f\~e&`PV
} v5wI?HE
l4F4o6:]n
/** =Gd[Qn83.%
* @return Returns the page. ]Nt97eD)
*/ R^](X*
public Page getPage(){ )gR14a
return page; Lj(hk@
} ;y6Jo
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/** >o 3X)
* @param content P
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* The content to set. Di *+Cz;gK
*/ An[*Jx
public void setContent(List content){ qvYYKu
this.content = content; ~c?yHpZx%
} 4PD"[a="
UXQ{J5Ox+
/** l,*Q?q
* @param page H
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* The page to set. h#]}J}si
*/ <mY`<(bc
publicvoid setPage(Page page){ {, APZ`q|
this.page = page; c#"\&~. P
} _5
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} 5B2x#
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]N=C%#ki!
.2xypL8(
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2. 编写业务逻辑接口,并实现它(UserManager, ;S`N q%,
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UserManagerImpl) s7xRry
java代码: i'e^[oZ
6^{ hY^Z
D<++6HN
/*Created on 2005-7-15*/ niy@'
package com.adt.service; 0^E!P>
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import net.sf.hibernate.HibernateException; { tR=D_5
@%\ANM$S
import org.flyware.util.page.Page; +o'. !sRH
_hh|/4(
import com.adt.bo.Result; xo@N~
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/** g=U?{<8.m
* @author Joa X'?v8\mPK
*/ &2xYG{Z
publicinterface UserManager { Jh466;
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public Result listUser(Page page)throws (
?/0$DB
TdQ^^{SRp
HibernateException; r]HLO'<]
!%s7I^f*
} "apv)xdW
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2#*
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2WUBJ-qnuT
java代码: ^_+ks/
U1q$B32
+:'Po.{"
/*Created on 2005-7-15*/ {eZj[*P
package com.adt.service.impl; #[KwR\b{:+
:X4\4B*~
import java.util.List; M9&tys[ KX
~ml\|
import net.sf.hibernate.HibernateException; @tj0Ir v
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import org.flyware.util.page.Page; SD.ze(P
import org.flyware.util.page.PageUtil; #[[p/nAy}A
^U`q1Pg5
import com.adt.bo.Result; XdS<51 C
import com.adt.dao.UserDAO; $ 1dI
import com.adt.exception.ObjectNotFoundException; |Q I3H]T7
import com.adt.service.UserManager; +;!w;t
WX=+\`NyJ(
/** P)\f\yb
* @author Joa 3\WES!
*/ F
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publicclass UserManagerImpl implements UserManager { <.v6w*+{/
n9J>yud|
private UserDAO userDAO; [KE4wz+s{
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/** u?J(l)gd
* @param userDAO The userDAO to set. CD tYj
*/ Q-au)R,
publicvoid setUserDAO(UserDAO userDAO){ -[`W m7en
this.userDAO = userDAO; 0[i]PgIH
} ]Aluk|"`U
n=>Gu9`
/* (non-Javadoc) xeH#)QJt
* @see com.adt.service.UserManager#listUser l|fd,
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(org.flyware.util.page.Page) =|#-Rm^YB
*/ PA=BNKlH
public Result listUser(Page page)throws *7v PU:Q[
6,h<0j{
HibernateException, ObjectNotFoundException { jF5JpyOc
int totalRecords = userDAO.getUserCount(); &%bX&;ECzf
if(totalRecords == 0) ]e3nnS1*.
throw new ObjectNotFoundException w[+!c-A:H
5;Z~+$1
("userNotExist"); ""a8eB6
page = PageUtil.createPage(page, totalRecords); co@8w!W
List users = userDAO.getUserByPage(page); lz*2wGI9
returnnew Result(page, users); jFc{$#g-
} kj#yG"3+
~k%\ LZ3s
} b7,qzh
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i~9)Hz;!
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 B>mQ\Q
!INr
询,接下来编写UserDAO的代码: pqr"x2=.
3. UserDAO 和 UserDAOImpl: a&[n Vu+
java代码: BY d3 rI
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aF=VJ+5
/*Created on 2005-7-15*/ o MAK[$k;
package com.adt.dao; =ht@7z8QM
EAkP[au.
import java.util.List; L!G3u/
zN:752d^+r
import org.flyware.util.page.Page; Cf N; `
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import net.sf.hibernate.HibernateException; ,rdM{ r
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/** 3/e !7
* @author Joa 1%+^SR72
*/ D5p22WY
publicinterface UserDAO extends BaseDAO { FN
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publicList getUserByName(String name)throws o(zg_!P
L }mhMxOTi
HibernateException; x9e
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publicint getUserCount()throws HibernateException; 4kM<L}J#
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publicList getUserByPage(Page page)throws >xjy
P!bca
<b\urtoJ
HibernateException; MI }D%n*
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$$L^
} fm*Hk57
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x,%&[6(
S@#L!sT`u
-*A'6%`
java代码: |3LMVN
Q'VS]n
8\9EDgT
/*Created on 2005-7-15*/ 7,zARWB!?
package com.adt.dao.impl; On^#x]
8{YxUD
import java.util.List; V("1\
_biJch
import org.flyware.util.page.Page; D/WS
{JgN^R<5<f
import net.sf.hibernate.HibernateException; p"@|2a
import net.sf.hibernate.Query; X`b5h}c
[oj"Tn(
import com.adt.dao.UserDAO; SXEiyy[7v
ht|r+v-
/** >`:+d'Jv0
* @author Joa 66*o2D\Q*G
*/ PwW @I~@>
public class UserDAOImpl extends BaseDAOHibernateImpl 'gGB-=yvbO
?>Aff`dHY
implements UserDAO { Xd6y7s
n1Jz49[r
/* (non-Javadoc) q1y4B`
* @see com.adt.dao.UserDAO#getUserByName iIFQRnpu;3
qpl5n'qHUc
(java.lang.String) Q6K)EwN
*/ L
~w=O!
publicList getUserByName(String name)throws eW0=m:6
)a\h5nQI)
HibernateException { 7;NV
1RV
String querySentence = "FROM user in class u*{ _WL[(
(Y([^N q
com.adt.po.User WHERE user.name=:name"; \0h/~3
Query query = getSession().createQuery &pm{7nH
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(querySentence); .TC
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query.setParameter("name", name); J|-HZ-Wk|J
return query.list(); n^N]iw{G
} W1Qc1T8
wVDB?gy%#
/* (non-Javadoc) lIg2iun[n
* @see com.adt.dao.UserDAO#getUserCount() Wi^rnr'Ss
*/ }eM<A$J
publicint getUserCount()throws HibernateException { N_D+d4@
int count = 0; 4- _lf(#i
String querySentence = "SELECT count(*) FROM P-[K*/bPw
VU9P\|c@<
user in class com.adt.po.User"; .5;LL,S-
Query query = getSession().createQuery -G#k/Rz6
"Q{~Bj~
(querySentence); 9^ p{/Io
count = ((Integer)query.iterate().next Hs=N0Sk]j
;
,jLtl
()).intValue(); V(LFH9.Mp
return count; l-}5@D[
} N+qLxk
JyC&L6[]Z
/* (non-Javadoc) xY2_*#{.
* @see com.adt.dao.UserDAO#getUserByPage JZ/O0PW
8G&+
(org.flyware.util.page.Page) f\|?_k]
*/ ApYud?0b
publicList getUserByPage(Page page)throws s}9tK(4v
PMhhPw]
HibernateException { lk1Gs{(qhH
String querySentence = "FROM user in class zK4
8vo
~49N
com.adt.po.User"; !]+Z%ed`%
Query query = getSession().createQuery 6F.7Ws<
F(9
Y/UXH
(querySentence); U!?gdX
query.setFirstResult(page.getBeginIndex()) <W59mweW#5
.setMaxResults(page.getEveryPage()); ywynx<Wg
return query.list(); [Cj)@OC
} gT&