Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 nTys4R
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @up&q
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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 5LQk8NPh
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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 Hp btj
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分页支持类: U^%9
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java代码: gtD
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package com.javaeye.common.util; Wrmgu}q
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import java.util.List; ,{k<JA{
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publicclass PaginationSupport { Y[W6Sc
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publicfinalstaticint PAGESIZE = 30; h`=r)D
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privateint pageSize = PAGESIZE; zhNQuK,L
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privateList items; 6\NvG,8
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privateint totalCount; HLVQ7
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privateint[] indexes = newint[0]; Zr=ib
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privateint startIndex = 0; 5J
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public PaginationSupport(List items, int 0!pJ5q ,A
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totalCount){ gNqAj# m
setPageSize(PAGESIZE); 4sTMgBzw
setTotalCount(totalCount); :vpl+)n
setItems(items); IroPx#s:i
setStartIndex(0); kVd5,Qd
} x|8^i6xB
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public PaginationSupport(List items, int 2`EVdl7B]
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totalCount, int startIndex){ P$_&
setPageSize(PAGESIZE); +~N!9eMc
setTotalCount(totalCount); K*1.'9/
setItems(items); oe9lF*$/
setStartIndex(startIndex); 3f"C!l]Xu
} @o6R[5(
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public PaginationSupport(List items, int sf$o(^P9\A
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totalCount, int pageSize, int startIndex){ J/ vK6cO\
setPageSize(pageSize); (-,>qMQs
setTotalCount(totalCount); 5X#E@3g5
setItems(items); *$S#o#5
setStartIndex(startIndex); ziiwxx_
} \9`#]#1bx5
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publicList getItems(){ (,B#t7ka
return items; FH8k'Hxg
} 3#c3IZ-;
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publicvoid setItems(List items){ Xh
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this.items = items; BJk
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} Be2lMC
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publicint getPageSize(){ ,$N#Us(Wa
return pageSize; _[t8rl
} ?T!)X)A#
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publicvoid setPageSize(int pageSize){ $,ikv?"L
this.pageSize = pageSize; VL\t>n
} [ *>AN7W
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publicint getTotalCount(){ uOd&XW
return totalCount; K\u_Ji]k
} y t5H oy
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publicvoid setTotalCount(int totalCount){ mV)+qXC
if(totalCount > 0){ pr&=n;_ n
this.totalCount = totalCount; /<{: I \<
int count = totalCount / D d,2;#_
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pageSize; ac8P\2{"
if(totalCount % pageSize > 0) ok{!+VCB5
count++; SwW['c'*]B
indexes = newint[count]; b?T
for(int i = 0; i < count; i++){ oyvKag
indexes = pageSize * n}?wVfEy
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} &%mXYj3y5
}else{ !RH.|}
this.totalCount = 0; /.1.MssQM
} yK%ebq]
} @7<uMasfp
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publicint[] getIndexes(){ m@Rtlb
return indexes; y7)(LQRE
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} ]uQqn]+I!
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publicvoid setIndexes(int[] indexes){ k[kju%i4
this.indexes = indexes; ._PzYE|m2
} ~}"]&%Q{J
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publicint getStartIndex(){ [yS#O\$'e
return startIndex; \ck+GW4&
} (Pbg[AY
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publicvoid setStartIndex(int startIndex){ bZ1 78>J]
if(totalCount <= 0) yuhnYR\`m
this.startIndex = 0; ~*W!mlg
elseif(startIndex >= totalCount) SF*n1V3hx
this.startIndex = indexes 3W_PE+:Kr
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[indexes.length - 1]; x@Hd^xH`
elseif(startIndex < 0) .2)
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this.startIndex = 0; 04U")-\O
else{ N<(.%<!
this.startIndex = indexes tjT>VwqH
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[startIndex / pageSize]; ._O
} ACq7dLys,B
} p< "3&HA
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publicint getNextIndex(){ cLVe T
int nextIndex = getStartIndex() + :'iYxhM.V
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pageSize; W ~f(::
if(nextIndex >= totalCount) /FP5`:PfL
return getStartIndex(); `n5"0QRd
else j _L@U2i
return nextIndex; r.ZF_^y}+
} jhbonuV_
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publicint getPreviousIndex(){ 0&_UH}10
int previousIndex = getStartIndex() - Vv1|51B
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pageSize; $-}e; V Zb
if(previousIndex < 0) *^%Q0mU[
return0; I/gjenUK
else
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return previousIndex; 9}a_:hAy/
} 3I\n_V<
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} V-'K6mn;
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抽象业务类 ,<BbpIQ2o
java代码: *}k;L74|
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/** LI2&&Mw
* Created on 2005-7-12 JM1R ;i6
*/ D%6;^^WyUx
package com.javaeye.common.business; om?-WJI
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import java.io.Serializable; Mi'8
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import java.util.List; 26T "XW'_
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import org.hibernate.Criteria; 5%sE]Y#
import org.hibernate.HibernateException; 2MZCw^s>
import org.hibernate.Session; Vq;dJ%sY
import org.hibernate.criterion.DetachedCriteria; >SPh2[f
import org.hibernate.criterion.Projections; oF(Lji?m
import ;qH O OT
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org.springframework.orm.hibernate3.HibernateCallback; #Zrlp.M4
import Jgnhn>dHe
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org.springframework.orm.hibernate3.support.HibernateDaoS ;2B{ 9{
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upport; ?-^~f
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import com.javaeye.common.util.PaginationSupport; (?nCyHC%g
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public abstract class AbstractManager extends `ZC<W]WYX/
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HibernateDaoSupport { x c{hC4^V
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privateboolean cacheQueries = false; ,}K<*t[I
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privateString queryCacheRegion; !.d@L6
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publicvoid setCacheQueries(boolean 2RSt)3!},
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cacheQueries){ yn#X;ja-
this.cacheQueries = cacheQueries; y*X_T,K8
} VkZ7#
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publicvoid setQueryCacheRegion(String }iuWAFZbGS
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queryCacheRegion){ I_RsYw
this.queryCacheRegion = T#>7ub
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queryCacheRegion; ynbuN x*
} AM!G1^c
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publicvoid save(finalObject entity){ D*lKn62
getHibernateTemplate().save(entity); K5lmVF\$P
} jYKor7KTqT
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publicvoid persist(finalObject entity){ X7rMeu
getHibernateTemplate().save(entity); uCcYPvm
} SJHr_bawd
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publicvoid update(finalObject entity){ Mxv;k%l|E|
getHibernateTemplate().update(entity); N0r16# -g
} [sW3l:^
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publicvoid delete(finalObject entity){ /FRm2m83
getHibernateTemplate().delete(entity); S_Wrw z
} 8SGo9[U2
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publicObject load(finalClass entity, .X;3,D[w
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finalSerializable id){ bD?VU<)3
return getHibernateTemplate().load R~PA1wDZ
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(entity, id); aeD ;5VV
} sfNE68I2
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publicObject get(finalClass entity, I"ok&^t^}
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finalSerializable id){ h5^Z2:#
return getHibernateTemplate().get ,LnII
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(entity, id); ;<ZLcTL
} S Em Q@1
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publicList findAll(finalClass entity){ N(Tz%o4
return getHibernateTemplate().find("from @"^0%/2-
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" + entity.getName()); N'GeHByIT
} |EJD3&
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publicList findByNamedQuery(finalString (^Y~/
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namedQuery){ IhVO@KJI
return getHibernateTemplate vwxXgk
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().findByNamedQuery(namedQuery); QD0"rxZJ
} ?M\{&mlF
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publicList findByNamedQuery(finalString query, #
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finalObject parameter){ ,)vDeU
return getHibernateTemplate 75XJL;W #
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().findByNamedQuery(query, parameter); \nPEyw,U
} X\bOz[\
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publicList findByNamedQuery(finalString query, vH :LQ!2
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finalObject[] parameters){ +%ee8|\
return getHibernateTemplate AP'*Nh@Ik(
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().findByNamedQuery(query, parameters); 7$CBx/X50)
} .y!<t}
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publicList find(finalString query){ n>BkTaI
return getHibernateTemplate().find MygfT[_
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(query); +ga k#M"n\
} { vKLAxc
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publicList find(finalString query, finalObject e7m*rh%5>
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parameter){ rf?qdd(~cH
return getHibernateTemplate().find )\eI;8
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(query, parameter); jBgP$g
} O_ChxX0KP
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ 0vtt"f)Y[
return findPageByCriteria VKq=7^W
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); l|/ep:x8
} t"=
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public PaginationSupport findPageByCriteria '
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(final DetachedCriteria detachedCriteria, finalint pi
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startIndex){ @)|C/oA
return findPageByCriteria .!f$
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(detachedCriteria, PaginationSupport.PAGESIZE, %k;|\%B`
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startIndex); \#Pfj&*
} ^>i63Yc
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public PaginationSupport findPageByCriteria Hea;?4Vg
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(final DetachedCriteria detachedCriteria, finalint y~q8pH1
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pageSize, %p2Sh)@M
finalint startIndex){ FFu9&8Y
return(PaginationSupport) v^#~98g]
Dp)=0<$y
getHibernateTemplate().execute(new HibernateCallback(){ qU#1i:(F*
publicObject doInHibernate A-ZN F4
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(Session session)throws HibernateException { Bj1?x
Criteria criteria = Dey<OE&
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detachedCriteria.getExecutableCriteria(session); 2QJ{a46}
int totalCount = 2zs73:z
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((Integer) criteria.setProjection(Projections.rowCount z^#;~I @M
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()).uniqueResult()).intValue(); C-\S/yd
criteria.setProjection ]pH-2_
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(null); FVaQEMZ^
List items = D ,o}el
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criteria.setFirstResult(startIndex).setMaxResults @d
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(pageSize).list(); G!>z;5KuS
PaginationSupport ps = q|!-0B@
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new PaginationSupport(items, totalCount, pageSize, apg=-^L'
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startIndex); M%2+y5
return ps; Wu[&Wv~
} `w.n]TR
}, true); }\\KYyjY
} mID"^NOi#
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public List findAllByCriteria(final s$Z
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DetachedCriteria detachedCriteria){ GP?M!C,/}k
return(List) getHibernateTemplate +a^nlW9g
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().execute(new HibernateCallback(){ @~!wDDS
publicObject doInHibernate aMWmLpv4'
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(Session session)throws HibernateException { {^CY..3
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Criteria criteria = 9x>d[-#y:J
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detachedCriteria.getExecutableCriteria(session); ?9e_gV{&;
return criteria.list(); rDm~h~u5
} 4Jp:x"w
}, true); Q6PHpaj
} \pPY37l
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public int getCountByCriteria(final 0)Uce=t`
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DetachedCriteria detachedCriteria){ xN5)
Integer count = (Integer) +O8%Hm
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getHibernateTemplate().execute(new HibernateCallback(){ ,]bhy p
publicObject doInHibernate JZ)RGSG i
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(Session session)throws HibernateException { 00(on28b
Criteria criteria = '*K :
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detachedCriteria.getExecutableCriteria(session); Z"/p,A9W9|
return (up~[
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criteria.setProjection(Projections.rowCount <CS(c|7
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()).uniqueResult(); f86XkECZ;`
} 6Y^23W F
}, true); &-;4.op
return count.intValue(); !\-{D$E?H
} ,vr? 2k
} g2BHHL;`
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用户在web层构造查询条件detachedCriteria,和可选的 #*D)Q/k
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C].iCxn
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PaginationSupport的实例ps。 ,kiv>{
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ps.getItems()得到已分页好的结果集 X.OD`.!>
ps.getIndexes()得到分页索引的数组 Bn^0^J-
ps.getTotalCount()得到总结果数 @ju@WY45$^
ps.getStartIndex()当前分页索引 34`'M+3
ps.getNextIndex()下一页索引 uW=k K0E
ps.getPreviousIndex()上一页索引 2a-w%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Q!o'}nA
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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 aI%g2q0f
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一下代码重构了。 KxI&G%z
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我把原本我的做法也提供出来供大家讨论吧: srr
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首先,为了实现分页查询,我封装了一个Page类: srPWE^&