Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N>A*N,+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .7nr :P
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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
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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 Je6=N3)
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分页支持类: :K)=Hf2y
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java代码: *<**rY*
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package com.javaeye.common.util; /?; 8F
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import java.util.List; ?q%)8 E
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publicclass PaginationSupport { R":nG7o
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publicfinalstaticint PAGESIZE = 30; `aS9o]t
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privateint pageSize = PAGESIZE; (zFUC]
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privateList items; !S/hH% C
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privateint totalCount; !@_( W
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privateint[] indexes = newint[0]; up~l4]b+
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privateint startIndex = 0; t:X[Blw3$
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public PaginationSupport(List items, int )y7SkH|
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totalCount){ [G/q*a:K
setPageSize(PAGESIZE); H].
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setTotalCount(totalCount); u_o>v{&i
setItems(items); 6NCa=9
setStartIndex(0); 6t5)rlT
} dm Lgt)-t
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public PaginationSupport(List items, int bl>MD8bzLE
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totalCount, int startIndex){ "Yn<]Pa_
setPageSize(PAGESIZE); 62}bs/%
setTotalCount(totalCount);
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setItems(items); )>ed6A1
setStartIndex(startIndex); [|2uu."$
} @NXGVmY1}
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public PaginationSupport(List items, int \<VwGbzFi
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totalCount, int pageSize, int startIndex){ Y962rZ
setPageSize(pageSize); DU7kZ
setTotalCount(totalCount); o_gpBaWD
setItems(items); Lp%V$'
setStartIndex(startIndex); >qn@E?Uf
} G{ rUqo
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publicList getItems(){ }Kq5!XJV9C
return items; eb:mp/
} :y'D] ,_
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publicvoid setItems(List items){ {Gs&u>>R"^
this.items = items; *?gn@4Ly
} VG'oy
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publicint getPageSize(){ #UC4l]Ru A
return pageSize; fp9ksxb@m
} Z{/C4" F
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publicvoid setPageSize(int pageSize){ sp[nKo^
this.pageSize = pageSize; {"e/3
} 0x0.[1mB
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publicint getTotalCount(){ 1+o >#8D
return totalCount; "t8mQ;n
} 8 &VwAo
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publicvoid setTotalCount(int totalCount){ 4aAr|!8|h!
if(totalCount > 0){ 0i$jtCCL(
this.totalCount = totalCount; kT UQ8U
int count = totalCount / 9U58#
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pageSize; K4xZT+Qb
if(totalCount % pageSize > 0) %yQ-~T@
count++; *ZGQ`#1.X6
indexes = newint[count]; x}1(okc
for(int i = 0; i < count; i++){ ~SJOynSz,
indexes = pageSize * ls,gQ]B:P
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} l~&efAJ-$
}else{ `R8~H7{I6
this.totalCount = 0; ~MO'%'@
} 9XS+W
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} /k1&?e
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publicint[] getIndexes(){ h|%d=`P,
return indexes; %M9^QHyo@
} [}lv!KmzW
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publicvoid setIndexes(int[] indexes){ i(,R$AU
this.indexes = indexes; K]@^8e$(
} -H.;73Kb[
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publicint getStartIndex(){ h&yaug,.
return startIndex; Y*f7& '[
} >K-O2dry*
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publicvoid setStartIndex(int startIndex){ jRB:o?S
if(totalCount <= 0) cY#TH|M
this.startIndex = 0; zv#i\8h^p
elseif(startIndex >= totalCount) 3 %dbfT j
this.startIndex = indexes d&?B/E^
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[indexes.length - 1]; 3Luv$6
elseif(startIndex < 0) :":W(O
this.startIndex = 0; OU9=O>
else{ 0+r/>-3]
this.startIndex = indexes HK&F'\'}
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[startIndex / pageSize]; zK:/
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}
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} ;=)CjC8)
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publicint getNextIndex(){ # JuO
int nextIndex = getStartIndex() + 'L3 \ I
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pageSize; [rPW@|^5
if(nextIndex >= totalCount) TmX~vZ
return getStartIndex(); ,[Cl 'B
else [b;Oalw
return nextIndex; Ylt[Ks<2
} %F&j B
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publicint getPreviousIndex(){ S3qUzK
int previousIndex = getStartIndex() - 9KXp0Q?-$
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pageSize; {Fb)Z"8]
if(previousIndex < 0) &R*d/~SU
return0; 0yAvAx
else yo
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return previousIndex; |[o2S9 0
} r*+9<8-ZX<
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} 0U`Ic_.
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抽象业务类 Z/beROW )
java代码: =/dW5qy;*+
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/** 3\mFK$#sr
* Created on 2005-7-12 i,4JS,82I
*/ 7BI0g@$Nn]
package com.javaeye.common.business; G =< KAJ
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import java.io.Serializable; M9f*7{c
import java.util.List; u%}vTCg*p
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import org.hibernate.Criteria; t'9E~_!C
import org.hibernate.HibernateException; IyP\7WZ
import org.hibernate.Session; Ujj2A^
import org.hibernate.criterion.DetachedCriteria; tanuP@O
import org.hibernate.criterion.Projections; )2^OBfl7
import 9sE>K)
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org.springframework.orm.hibernate3.HibernateCallback; O=mGL
import UBC[5E$
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org.springframework.orm.hibernate3.support.HibernateDaoS @KS:d\l}U
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upport; `Rm B{qgB
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import com.javaeye.common.util.PaginationSupport; 4-3B"
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public abstract class AbstractManager extends dr/!wr'&hS
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HibernateDaoSupport { `b7o
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privateboolean cacheQueries = false; f"-<Z_
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privateString queryCacheRegion; ;[9cj&7C<
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publicvoid setCacheQueries(boolean },f7I^s|
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cacheQueries){ h/_z QR-
this.cacheQueries = cacheQueries; !J2Lp
} slQKkx \Dn
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publicvoid setQueryCacheRegion(String W%h<@@c4,
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queryCacheRegion){ MESQAsx%
this.queryCacheRegion = }W|CIgF*
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queryCacheRegion; 1m![;Pg3
} 'GW@P
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publicvoid save(finalObject entity){ {UPIdQ'g
getHibernateTemplate().save(entity); HQUL?URt
} ^NnZYr.
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publicvoid persist(finalObject entity){ uNRGbDMA=
getHibernateTemplate().save(entity); 3(PU=
} qmL!"ZRLF
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publicvoid update(finalObject entity){ 5SKu \H\
getHibernateTemplate().update(entity); G&n_vwZ%
} 2qn~A0r
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publicvoid delete(finalObject entity){ KM\`,1?x92
getHibernateTemplate().delete(entity); f%|g7[
} GuS3O)6Sg
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publicObject load(finalClass entity, Jhut>8
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finalSerializable id){ nwkhGQ
return getHibernateTemplate().load sY#K=5R
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(entity, id); f9\7v_
} E=x\f "Z
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publicObject get(finalClass entity, 5?I]\Tb
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finalSerializable id){ QR8F'7S
return getHibernateTemplate().get d5],O48A
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(entity, id); |ow hF
}
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publicList findAll(finalClass entity){ jgO{DNe(=
return getHibernateTemplate().find("from Q;^([39DI
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" + entity.getName()); {Rz`)qqE
} v~xG*e
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publicList findByNamedQuery(finalString Cn{UzSKfs
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namedQuery){ x)GoxH~#
return getHibernateTemplate #IXQ;2%E
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().findByNamedQuery(namedQuery); HmiwpI
} 8t7hN?,t
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publicList findByNamedQuery(finalString query, =AAH}
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finalObject parameter){ +,KuYa{lu
return getHibernateTemplate +X- k)9
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().findByNamedQuery(query, parameter); 1ii.nt1u
} UHg^F4>4
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publicList findByNamedQuery(finalString query, Z?@07Y[|K
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finalObject[] parameters){ 0-#ct1-
return getHibernateTemplate {C6Yr9
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().findByNamedQuery(query, parameters); Fd91Y
} FUOvH85f
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publicList find(finalString query){ dG|\geD
return getHibernateTemplate().find UnMDdJ\
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(query); @z,'IW74V
}
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publicList find(finalString query, finalObject :,u+[0-S
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parameter){ p;H1,E:Re#
return getHibernateTemplate().find D\TL6"wo
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(query, parameter); ^:q(ksssY
} ht-6_]+ME
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public PaginationSupport findPageByCriteria qI"mW@G~H
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(final DetachedCriteria detachedCriteria){ T S.lFg:K
return findPageByCriteria Rza\n8
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); mB
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} (+U!#T]'D
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public PaginationSupport findPageByCriteria }s|v-gRM{
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(final DetachedCriteria detachedCriteria, finalint 5N6%N1
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startIndex){ n}+
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return findPageByCriteria p\HXE4d'
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(detachedCriteria, PaginationSupport.PAGESIZE, ?L
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startIndex); Vz,WPm$I
} WGO=@jkf
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public PaginationSupport findPageByCriteria vxm`[s |QC
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(final DetachedCriteria detachedCriteria, finalint N;w1f"V}
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pageSize, -g>27EI5
finalint startIndex){ vJ{\67tK
return(PaginationSupport) AD5t uY
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getHibernateTemplate().execute(new HibernateCallback(){ e (f)?H
publicObject doInHibernate JDs<1@ \
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(Session session)throws HibernateException { U8c0C/
Criteria criteria = g5"g,SFGr
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detachedCriteria.getExecutableCriteria(session); dYsqF
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int totalCount = \i&yR]LF
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((Integer) criteria.setProjection(Projections.rowCount EbW7Av
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()).uniqueResult()).intValue(); <)}*S
criteria.setProjection J^W.TM&q$,
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(null); AV'>
List items = jy*wj7fj1
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criteria.setFirstResult(startIndex).setMaxResults RsY<j& f
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(pageSize).list(); <wuP*vI"h
PaginationSupport ps = f;b(W
toCN{[
new PaginationSupport(items, totalCount, pageSize, >Kr,(8rA
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startIndex); vSX
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return ps; D"o>\Q
} ]EK"AuEz`
}, true); wb{y]~&6K
} *n*OVI8L
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public List findAllByCriteria(final *yf+5q4t
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DetachedCriteria detachedCriteria){ p$ko=fo-*_
return(List) getHibernateTemplate S:5Nh^K
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().execute(new HibernateCallback(){ ~E!"YkIr
publicObject doInHibernate )rXP2Z
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(Session session)throws HibernateException { Ve=0_GR0
Criteria criteria = (zhmZm
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detachedCriteria.getExecutableCriteria(session); &o8\ $A
return criteria.list(); &
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} Q~]R#S
}, true); 9xSAWKr,l
} 5~sJ$5<,
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public int getCountByCriteria(final eg}|%GG
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DetachedCriteria detachedCriteria){ hA"N&v~
Integer count = (Integer) o~}q@]]
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getHibernateTemplate().execute(new HibernateCallback(){ K.cNx
publicObject doInHibernate <1@_MYo
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(Session session)throws HibernateException { tf/ f-S
Criteria criteria = MLR3A
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detachedCriteria.getExecutableCriteria(session); [A3hrSw
return $<yb~z7J
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criteria.setProjection(Projections.rowCount G,XFS8{%
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()).uniqueResult(); k_^d7yH
} MTF:mLJ
}, true); 2x{3' ^+l
return count.intValue(); >g F
} eF2<L [9
} eAl&[_o|S
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用户在web层构造查询条件detachedCriteria,和可选的 _h.[I8xgYG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1LE8,Gm&
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PaginationSupport的实例ps。 ;[6u79;I
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ps.getItems()得到已分页好的结果集 VE GUhI/d
ps.getIndexes()得到分页索引的数组 OixQlAb{
ps.getTotalCount()得到总结果数 Ck[Z(=b$$:
ps.getStartIndex()当前分页索引 }q~A( u
ps.getNextIndex()下一页索引 Z|j8:Ohz
ps.getPreviousIndex()上一页索引 \V&ly/\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Bd7A-T)q!
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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
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一下代码重构了。 |D^[]*cEH
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我把原本我的做法也提供出来供大家讨论吧: 1r8]EaI
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首先,为了实现分页查询,我封装了一个Page类: ^%_LA't'R
java代码: (57x5qP
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/*Created on 2005-4-14*/ ~=c#Ff=Z
package org.flyware.util.page; 1&m08dZm5
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/** jOe %_R
* @author Joa |_ ;-~bmb
* L=VuEF
*/ s~TYzfA
publicclass Page { inhb> zB
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/** imply if the page has previous page */ n ,H;PB
privateboolean hasPrePage; N-5lILuJJ
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/** imply if the page has next page */ 8Y4YE(x5
privateboolean hasNextPage; @@! R
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/** the number of every page */ <x1(}x:u`
privateint everyPage; j7i[z>:Y
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/** the total page number */ %5uuB4P&|$
privateint totalPage; )~WxNn3rx
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/** the number of current page */ O[-wm;_(=*
privateint currentPage; ZL@7Mr!e
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/** the begin index of the records by the current 2sf/^XC1
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query */ $<T)_g
privateint beginIndex; xo?f90+(
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/** The default constructor */ 2O4UytN
public Page(){ esxU44
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} J]Y." hi
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/** construct the page by everyPage (?~F}u
v
* @param everyPage cU*7E39
* */ ogPxj KSI
public Page(int everyPage){ IU3OI:uq
this.everyPage = everyPage; /Bb\jvk-E
} gBresHrlH
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/** The whole constructor */ \24neD4cM@
public Page(boolean hasPrePage, boolean hasNextPage, Yr[1-Oy/k
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int everyPage, int totalPage, ,Kdvt@vle
int currentPage, int beginIndex){ R`/nsou
this.hasPrePage = hasPrePage; 3"q%-M|+Q
this.hasNextPage = hasNextPage; R{4O*i8#
this.everyPage = everyPage; ncu>
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this.totalPage = totalPage; Y5(`/
this.currentPage = currentPage; \alRBH qE
this.beginIndex = beginIndex; "IB)=Hc
} jp2l}C
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/** o.sa?*
* @return 3}XUYF;
* Returns the beginIndex. #E*jX-JT
*/ d<!bE(
publicint getBeginIndex(){ O@Xl_QNxc!
return beginIndex; +-xA/nU.c
} _Z2VS"yH
}Z2Y>raA\
/** LkJ3 :3O
* @param beginIndex b7HS3NYk
* The beginIndex to set. 377$c;4F
*/ fFiFc^
publicvoid setBeginIndex(int beginIndex){ ~Ge-7^Fo7
this.beginIndex = beginIndex; 5$N4<Lo7
} .XS rLb?
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/** ynDa4HB
* @return '0w'||#1
* Returns the currentPage. S[* e K
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*/ v%B^\S3)
publicint getCurrentPage(){ @{~x:P5g
return currentPage; [f^~Z'TIN/
} b)
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/** AnI ENJ
* @param currentPage G+}|gG8
* The currentPage to set. XnV|{X%]U
*/ Hn:%(Rg=aW
publicvoid setCurrentPage(int currentPage){ ]xV7)/b5G
this.currentPage = currentPage; :*@=px
} } fSbH
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/** #y2="$V
* @return 1\_4# @')
* Returns the everyPage. !MQo=k
*/ c1e7h l
publicint getEveryPage(){ U
= T[-(:H
return everyPage; W0l|E&fj[
} t5[{ihv~:
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/** >|H=25N>;
* @param everyPage dH?;!sJ
* The everyPage to set. F5&4x"c
*/ Ma wio5
publicvoid setEveryPage(int everyPage){ { 5h6nYu
this.everyPage = everyPage; %-H
} &eyFApM[Z
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/** mtmtOG_/=
* @return =3""D{l
* Returns the hasNextPage. F|Jo|02
*/ A*E$_N
publicboolean getHasNextPage(){ 4z?6[Cg<
return hasNextPage; %p@A8'b
} 5ahAp];
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/** Rnun() plJ
* @param hasNextPage p4|:u[:&
* The hasNextPage to set. eDIjcZ
*/ ld`oIEj!P_
publicvoid setHasNextPage(boolean hasNextPage){ c tTbvXP
this.hasNextPage = hasNextPage; >.QD:_@:
} q4lL7@_
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/** ow%s_yV]R
* @return A10/"Ec<u
* Returns the hasPrePage. zgqe@;{
*/ 8[
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publicboolean getHasPrePage(){ A+NLo[swwu
return hasPrePage; D",ZrwyJ
} )7[>/2aGd
ka*VQXk*
/** '2v,!G]^
* @param hasPrePage r'k-*I
* The hasPrePage to set. !dSY?1>U<
*/ f4]nz:2
publicvoid setHasPrePage(boolean hasPrePage){ ) Q]kUG#`
this.hasPrePage = hasPrePage; ;. /Tv84I^
} v!K%\h2A
\O72PC+
/** e#SNN-hKsJ
* @return Returns the totalPage. JzCfs<D
* z`m-Ca>6
*/ w%j 6zsTz
publicint getTotalPage(){ FpCj$y~3
return totalPage; vQYd!DSh
} BX2&tQSp
;sCX_`t0E
/** 03AYW)"}M
* @param totalPage y!
7;Z~"
* The totalPage to set. 'I*F(4x
*/ (\,mA-%E
publicvoid setTotalPage(int totalPage){ Vad(PS0
this.totalPage = totalPage; ~Og'IRf
} .KTDQA\
%\Ig{Rj;
} );7csh%
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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 1 NLawi6
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个PageUtil,负责对Page对象进行构造: k;l^wM
java代码: Su-LZ'C\
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/*Created on 2005-4-14*/ Cf2rRH
package org.flyware.util.page; Y-7x**I
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import org.apache.commons.logging.Log; o!wz:|\S
import org.apache.commons.logging.LogFactory; %`-NWAXL
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/** !fyE
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* @author Joa ~)Ny8Dh
* OCY7Bls4
*/ XZJ }nXy
publicclass PageUtil { /$]dVvhX%
pcoJ\&&W
privatestaticfinal Log logger = LogFactory.getLog Uiv;0Tovl
g}L2\i688
(PageUtil.class); ;{j:5+'
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/** ex&&7$CXc
* Use the origin page to create a new page MoO
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* @param page $BkdC'D
* @param totalRecords ,dK% [
* @return G2
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*/ E!C~*l]wJx
publicstatic Page createPage(Page page, int f.Q?-M
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totalRecords){ =HYMX"s
return createPage(page.getEveryPage(), ,t(y~Z
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page.getCurrentPage(), totalRecords); |o|0qG@g
} ,r:.
3.
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/** W5EB+b49KM
* the basic page utils not including exception ,`S"nq
w'?uJW
handler HaJD2wvr
* @param everyPage w9H%u0V?
* @param currentPage 3Akb|r
* @param totalRecords '?wv::t
* @return page 2gg5:9
*/ -QI1>7sl
publicstatic Page createPage(int everyPage, int +q1
@8
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currentPage, int totalRecords){ T[~ak"M
everyPage = getEveryPage(everyPage); QJvA
currentPage = getCurrentPage(currentPage); \E]s]ft;+
int beginIndex = getBeginIndex(everyPage, +.b~2K1
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currentPage); PHT;%;m=
int totalPage = getTotalPage(everyPage, !@p@u;djJ
[ wr0TbtV
totalRecords); Xp4pN{h e
boolean hasNextPage = hasNextPage(currentPage, D{PO!WzW
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totalPage); _lu.@IX-
boolean hasPrePage = hasPrePage(currentPage); D.)R8X
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returnnew Page(hasPrePage, hasNextPage, D9 ,~Fc
everyPage, totalPage, d=Q0/sI&
currentPage, L`yS'
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beginIndex); 3#^xxEu
} "<txg%j\J
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privatestaticint getEveryPage(int everyPage){ L+9a4/q
return everyPage == 0 ? 10 : everyPage; U3ED3)
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} L#m1!+J
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privatestaticint getCurrentPage(int currentPage){ <+
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return currentPage == 0 ? 1 : currentPage; j""u:l^+x
} &AoXv`l4
. m@Sk`s
privatestaticint getBeginIndex(int everyPage, int W29@`93
;_1D-Mf
currentPage){ :&9#p%/
return(currentPage - 1) * everyPage; N=)N
} maXQG&.F
Q<w rO
privatestaticint getTotalPage(int everyPage, int KZsSTB6J
{CYFM[V
totalRecords){ yLipuMNV
int totalPage = 0; $l7
<j_C
)LKutN?tBy
if(totalRecords % everyPage == 0) Y{f;qbEQH'
totalPage = totalRecords / everyPage; $
[0
else JY4 +MApN
totalPage = totalRecords / everyPage + 1 ; '<4/Md[
FJ}/g
?
return totalPage; x_s9DkX
} [;83
IoU}
`>g:
:
privatestaticboolean hasPrePage(int currentPage){ _~-VH&g0R
return currentPage == 1 ? false : true; P9SyQbcK
} 5ju\!Re3X
=Pd3SC})6V
privatestaticboolean hasNextPage(int currentPage, |J?KHI
cK1r9ED|
int totalPage){ Bd31>
%6
return currentPage == totalPage || totalPage == doW_vu
:>\ i
0 ? false : true; m';:):
} @'7'3+ c
,4)zn6tC
}3V Q*'X>i
} _@ev(B
nB`pfg
n]r7} 2hM
roVGS{4T\
B24wn8<
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。 |36d<b Io
-'*B%yy
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 N0vr>e`
K*d+pImrV
做法如下: PI)lJ\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 .Q>.|mu
r@%-S!$
的信息,和一个结果集List: MOJKz!%
java代码: SdeKRZ{o
hDSt6O4za
l> W?XH
/*Created on 2005-6-13*/ g;UB+Y 247
package com.adt.bo; %8DU}}Rj
+%UfnbZ
import java.util.List; 9NBFG~)|l[
tux/@}I
import org.flyware.util.page.Page; 6:fe.0H9
@_J~zo
/** P>9F(#u_(F
* @author Joa MRV4D<NQ
*/ L 1H!o!*
publicclass Result { pW 2NrBq@w
b>er 'U
private Page page; 4%Z! *W*
xVfAlN37(
private List content; )R(kXz=M
wzwEYZN(q
/** W_Z%CBjcT
* The default constructor sC(IeGbX
*/ 0r*E$|zZ
public Result(){ .hzzoLI2
super(); zn@<>o8hU
} X3-pj<JLY
zogw1g&C
/** hs!a'E
* The constructor using fields &5h{XSv
* o:W>7~$jr=
* @param page "3(""0Q
* @param content iVu
*/ KLBU8%
public Result(Page page, List content){ nD@/,kw"
this.page = page; _zvCc%
this.content = content; %@k@tD6
} l=GcgxD+"d
MzM"r"u
/** /Nt#|C>
* @return Returns the content. 4>-'w MW")
*/ Vzn0;
publicList getContent(){ ~! ;*C
return content; 7jL+c~
} ePv3M&\J
WXV (R,*Tc
/** %IL]
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* @return Returns the page. aMe]6cWHV>
*/ ]V0V8fU|
public Page getPage(){ Z$LWZg
return page; dWqKt0uh!
} `<2k.aW4e8
Q3[MzIk 4
/** =(2y$,6g?
* @param content )S@e&a|
* The content to set. +pXYBwH
7Q
*/ |;sL*Vr
public void setContent(List content){ IO3 p&sJ/
this.content = content; }Z#KPI8\Q
} T$rhz)_q
= >CADTU
/** M(8dKj1+
* @param page n_QSuh/Wn
* The page to set. )O\w'|$G
*/ 10R#}~D
publicvoid setPage(Page page){ .);~H#
this.page = page; IJa6W`}
} fGjYWw
} |>|f?^
Oy
EOb>
P1C{G'cR
/S2lA>
KCP$i@Pjv
2. 编写业务逻辑接口,并实现它(UserManager, XuS3#L/3p
M$_E:u&D
UserManagerImpl) 5|O~
java代码: ~wYGTm=(n
x3DUz
,2oF t\`.r
/*Created on 2005-7-15*/ 3r^Ls[ey
package com.adt.service; S!WG|75B
#O 2g]YH
import net.sf.hibernate.HibernateException; "o_s=^U
dhrh "x_?:
import org.flyware.util.page.Page; b3.
[l44,!Z&
import com.adt.bo.Result; corNw+|/w
c"KN;9c,
/** Db4(E*/pj!
* @author Joa {=K);z
*/ zVt1Ta:j
publicinterface UserManager { lCafsIB
X* 4C?v
public Result listUser(Page page)throws I+2#k\y
#zmt x0
HibernateException; H=lzW_(
?vt#M^Q
} aa2 vk)~
=&T%Jm}
d?:KEi-<7
M>qqe! c*
yz}ik^T
java代码: CWBlDz
.A6D&-&z
>0F)^W?
/*Created on 2005-7-15*/ HuT4OGBFpC
package com.adt.service.impl; R7\T.;8+
Cv[_N%3[
import java.util.List; J.;!l
OQ(w]G0LP
import net.sf.hibernate.HibernateException; + Vv+<M
lbs0i
import org.flyware.util.page.Page; 5Ve`j,`=<
import org.flyware.util.page.PageUtil; hGU
m7
*kYJwO^
import com.adt.bo.Result; TWSqn'<E
import com.adt.dao.UserDAO; T.(C`/VM
import com.adt.exception.ObjectNotFoundException; A_eO
import com.adt.service.UserManager; /a,"b8
2#
72B
/** o|G'vMph
* @author Joa $^:s)Yv
*/ Qm_IU!b
publicclass UserManagerImpl implements UserManager { `T\_Wje(
bv^wE,+?o
private UserDAO userDAO; f9K+o-P.h
7D(Eo{ue
/** CdZ. T/x
* @param userDAO The userDAO to set. m!5MGq~
*/ gV}c4>v(
publicvoid setUserDAO(UserDAO userDAO){ !zVjbYWY
this.userDAO = userDAO;
$UD$NSl
} ^'%Q>FVb
@.&KRAZ
/* (non-Javadoc) shgZru
* @see com.adt.service.UserManager#listUser ;
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A)#w~ X4
(org.flyware.util.page.Page) Sw.k,p*r
*/ !C(U9p. 0
public Result listUser(Page page)throws 2P/ Sq
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HibernateException, ObjectNotFoundException { R ;k1(p
int totalRecords = userDAO.getUserCount(); z0H+Or
if(totalRecords == 0) Qz4eQlWhp
throw new ObjectNotFoundException iE0x7x P_
j/t)=c
("userNotExist"); WA6reZ
page = PageUtil.createPage(page, totalRecords); Spu>
ac
List users = userDAO.getUserByPage(page); M3U?\g
returnnew Result(page, users); `]`S"W7&
} hG~HV{6
>*MGF=.QG
} HV&i! M@T
HvR5-?qQ
XuoyB{U
(gRTSd T?
mEmgr(W
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Cxd^i
,|g&v/WlC%
询,接下来编写UserDAO的代码: )[ QT?;
3. UserDAO 和 UserDAOImpl: qeDXG
java代码: 5O(U1
*
Nwj M=GG
u4tv=+jh
/*Created on 2005-7-15*/ Tn"@u&P
*
package com.adt.dao; 7{tU'`P>
W|Cs{rBc?
import java.util.List; j#~ S"t
ov<vSc<u
import org.flyware.util.page.Page; O7]kcA
@Q7^caG
import net.sf.hibernate.HibernateException; T[evh]koB
H|S hi /
/** 2:@,~{`#*
* @author Joa 3*T/ 7\
*/ C|V5@O?;&
publicinterface UserDAO extends BaseDAO { 2#
EQe$~}[
publicList getUserByName(String name)throws SdF+b+P]
d\R "?Sg
HibernateException; 1#3eY?Nb
YSzC's[
publicint getUserCount()throws HibernateException; ~Ede5Vg!!2
#@' B\!<@=
publicList getUserByPage(Page page)throws JXjH}C
NFy V02.
HibernateException; NoMlTh(O
p"7]zq]'
} O=vD6@QI
6i;q=N$'
PMi.)%++
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*~~J1.ja>
java代码: ay
=B<|!
'C=(?H)M
L=<$^ m
/*Created on 2005-7-15*/ U'^ G-@
package com.adt.dao.impl; ]XcWGQv~
a ]:xsJ~
import java.util.List; ?\I@w4
n{\d
import org.flyware.util.page.Page; 0nvT}[\H*
'0^lMQMg
import net.sf.hibernate.HibernateException; Z`f?7/"B
import net.sf.hibernate.Query; /U,(u9bq
uaYI3w@^
import com.adt.dao.UserDAO; 1Vkb}A,'
[wk1p-hf
/** x:i,l:x
* @author Joa W9{i ~.zo
*/ qu.AJ*
public class UserDAOImpl extends BaseDAOHibernateImpl M+M ;@3
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implements UserDAO { XI:+EeM?
?VCp_Ji
/* (non-Javadoc) $> ;|
* @see com.adt.dao.UserDAO#getUserByName s1R#X~d
39m8iI%w[
(java.lang.String) xi=0kO
*/ vT MCZ+^g
publicList getUserByName(String name)throws OLWn0
PdEPDyFk h
HibernateException { :fDzMD
String querySentence = "FROM user in class q6hH]Q>w*
0}YadNb7
com.adt.po.User WHERE user.name=:name"; +U<.MVOo.
Query query = getSession().createQuery belBdxa{"
OJ7Uh_;/
(querySentence); L8Q/!+K
query.setParameter("name", name); o6RT 4`
return query.list(); d04gmc&*
} zJh!Q**
G O"E>FyB
/* (non-Javadoc) 8#R%jjr%T
* @see com.adt.dao.UserDAO#getUserCount() ++UxzUd
*/ P9R-41!
publicint getUserCount()throws HibernateException {
'SXLnoeTa
int count = 0; :#\jx
String querySentence = "SELECT count(*) FROM ]<ay_w;
I?nU+t;
user in class com.adt.po.User"; 6kMEm)YjT
Query query = getSession().createQuery -7XaS&.4
,S
m?2<
(querySentence); _dECAk
&b
count = ((Integer)query.iterate().next |9F-ZH~6
4]E1x l
()).intValue(); _j4K
return count; R6`mmJ+'
} 9':Hh'
S|;}]6p
/* (non-Javadoc) bMsThoePT
* @see com.adt.dao.UserDAO#getUserByPage 5z_Kkf?o
@+_pj.D
(org.flyware.util.page.Page) xSO5?eR"u
*/ G^z>2P
publicList getUserByPage(Page page)throws ,Y#f0
UV</Nx)3
HibernateException { Pf;RJeD
String querySentence = "FROM user in class `Ba?4_>k
)iVuac]E++
com.adt.po.User"; ?=1i:h
Query query = getSession().createQuery 6mIeV0Q'
"r8N-
h/P
(querySentence); mwn$ey&QE
query.setFirstResult(page.getBeginIndex()) &4%78K\
.setMaxResults(page.getEveryPage()); + rM]RFi
return query.list(); +6~zMKp
} }A[5\V^D*
uKTYb#E7
} .g7\+aiTUd
IGo5b-ds
0+)1KU)I
@*uZ+$
D51s)?
至此,一个完整的分页程序完成。前台的只需要调用 zTl,VIa3p
J9f]=1`
userManager.listUser(page)即可得到一个Page对象和结果集对象 [g}0.J`_
]dV$H
的综合体,而传入的参数page对象则可以由前台传入,如果用 ++ 5!8Nv
a<]vHC7
webwork,甚至可以直接在配置文件中指定。 h#dfhcU>
5Vdy:l
下面给出一个webwork调用示例: 3[?;s}61
java代码: Su[(IMw
E$A=*-u
gxJ12'
m
/*Created on 2005-6-17*/ h`eHoKJ#w
package com.adt.action.user;
hFan$W$
'*Tt$0#o
import java.util.List; kIe)ocJg
qv>l
import org.apache.commons.logging.Log; Eg2SC? 5
import org.apache.commons.logging.LogFactory; {lUaN0O:
import org.flyware.util.page.Page; Z0v&AD=
<u1`o`|-
import com.adt.bo.Result; ]3Ibl^J
import com.adt.service.UserService; t0?tXe.B
import com.opensymphony.xwork.Action; C1qlB8(Wh>
RE-y5.kE^
/** sPl3JP&s
* @author Joa {qU;>;(
*/ h0A%KL
publicclass ListUser implementsAction{ P)hGe3
d/ @P;YN!
privatestaticfinal Log logger = LogFactory.getLog ?5^DQ|Hg ^
0QW;=@)d
(ListUser.class); ($8!r|g5#
4Me3{!HJ z
private UserService userService; )T&r770
$" =3e]<
private Page page; ka{!' ^
Mhb~wDQl
privateList users; E8t{[N6d
<xrya_R?
/* s;[=B
* (non-Javadoc) 9+8N-LZ
* bb+iUV|Do
* @see com.opensymphony.xwork.Action#execute() :QHh;TIG=<
*/ ,g3n/'rP%
publicString execute()throwsException{ !/!Fc'A
Result result = userService.listUser(page); E8wkqZN
page = result.getPage(); L$"pk{'
users = result.getContent(); a]6dhQ`
return SUCCESS; >svx
8CT
} 1zCgPiAem
u6:$AA
/** "5Z5x%3I
* @return Returns the page. W@%g_V}C*
*/ o3NB3@uj<
public Page getPage(){ _Kh8
<$h
return page; mtw{7E
} IJ:JH=8
V@EyU/VJ
/** 3{Zd<JYg4-
* @return Returns the users. V^><
=DNE
*/ Hq?dqg' %~
publicList getUsers(){ g:6`1C
return users; ;RQ}OCz9}8
} u?>8`]r
64<*\z_
/** N] pw7S%
* @param page n;:C{5
* The page to set. =rkW325O
*/ u_8Z^T
publicvoid setPage(Page page){ ^i8(/iwdJE
this.page = page; }}"|(2I
} PeLzZ'$D
(B?ZUXM,
/** m& D#5C
* @param users vTWm_ed+^
* The users to set. Bo'v!bI7
*/ 5aXE^.`
publicvoid setUsers(List users){ e)87
&
7
this.users = users; : &~LPmJ
} $U)nrni
}gE^HH'
/** <7gv<N6BQf
* @param userService "x0KiIoPk
* The userService to set. ?N@[R];
*/ zH#urF6<
publicvoid setUserService(UserService userService){ 5{v uN)K3
this.userService = userService; .&8a ;Q?c
} $ERiBALN:
} |8)\8b|VuC
%&s4YD/{
{K:]dO
2i NZz
(rq(y$N
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, qG]0z_dPE~
]*Kv[%r07c
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 O.8k [Ht
1?Tj
么只需要: 8]bLp
java代码: wLvM<p7OX
IABF_GwF
CT'#~~QB
<?xml version="1.0"?> XPnHi@x
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork lB8gD
NK:! U
1.0//EN" "http://www.opensymphony.com/xwork/xwork- eax"AmO
Yn0iu$;n
1.0.dtd"> :-(qqC:
%c8@
<xwork> EW+QVu@
>t%@)]*N
<package name="user" extends="webwork- [ A 7{}
.Sv/0&O
interceptors"> @18}'k
l 3 jlKB
<!-- The default interceptor stack name ,3!4
D^
o,@(]e~
--> yW"[}Lh4
<default-interceptor-ref a zO7C*_
*55unc
name="myDefaultWebStack"/> n8`WU3&
-MFePpUt
<action name="listUser" e_cK#9+
BKgCuz:y
class="com.adt.action.user.ListUser"> D6C h6i5$
<param I8YCXh
.nEiYS|T
name="page.everyPage">10</param> k)W&ZY
<result Q8.LlE999
POX{;[SV
name="success">/user/user_list.jsp</result> 4Tb"+Y}
</action> wti
>5D;uTy
u
</package> 2(Aw
GR_caP
</xwork> n9-WZsc1
vF/wV'Kk
e0<O6
ud"Kko Rt
H5o=nWQ6e
QV4FA&f&
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 4=N(@mS
0sB[]E|7[s
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 a|4Q6Ycu
'rA(+-.M;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 62K#rRS
t J&tNSjTi
qVjMflVoay
h
9}x6t,
>2X-98,
我写的一个用于分页的类,用了泛型了,hoho IaU%L6Q]
&
x_
#zN]
java代码: #7/39zTK
cH+ ~|3
hML-zZ
package com.intokr.util; q>5j (,6F
cS
Qb3}a\
import java.util.List; Fh|{ib
yhs:.h
/** i6g=fx6j*
* 用于分页的类<br> v-/vj/4>
* 可以用于传递查询的结果也可以用于传送查询的参数<br> $dA]GWW5A
* ]b:>7_la
* @version 0.01 {w7/M]m-
* @author cheng ExeZj8U
*/ E=`/}2
public class Paginator<E> { FW|_8q?}<
privateint count = 0; // 总记录数 9PMIF9"
privateint p = 1; // 页编号 |--Jd$ dj
privateint num = 20; // 每页的记录数 qwO@>wQ}~
privateList<E> results = null; // 结果 N,3iSH=cN[
?-)v{4{s
/** P%N)]b<c*
* 结果总数 ,i8%qm8
*/ B&6lG!K'?
publicint getCount(){ |68k9rq
return count; Rz[3cN)?q
} G\B+bBz
s[t<2)i
publicvoid setCount(int count){ L0GQH;Y,h
this.count = count; "fW
}6pS
} DJAKF
OkfxX&n
/** ./L)BLC i
* 本结果所在的页码,从1开始 \Pcn D$L
* dC|6z/
* @return Returns the pageNo. ,Q0H)//~
*/ M|fV7g
publicint getP(){ V Ew| N)
return p; t[@>u'YKt
} u8M_2r
beSU[
/** XUD Ztxa
* if(p<=0) p=1 A7|L|+ ?
* "F6gV;{Bt
* @param p /bPs0>5
*/ KSHq0A6/q%
publicvoid setP(int p){ 76KNgV)3
if(p <= 0) ={+8jQqi1
p = 1; 9C0#K\
this.p = p; -Mz [S
} DUh\x>^
]}p<P):hO
/** ge<D}6GQ
* 每页记录数量 ._Ww
*/ _l"nwEs
publicint getNum(){ ?_cOU@n
return num; lk[Y6yE
} ]vP}K
~"NuYM#@
/** To5hVL<Ex"
* if(num<1) num=1 Z*Gf`d:
*/ z?( b|v
publicvoid setNum(int num){ | L1+7
if(num < 1) 5t"FNL
<(M
num = 1; DfP-(Lm)
this.num = num; C+[)^2M{
} 0!7p5
! Dj2/][
/** V; CPn
* 获得总页数 S!+>{JyQ
*/ y@It#!u0
publicint getPageNum(){ o]<9wc:FZ
return(count - 1) / num + 1; a^pbBDi
W
} Jazg n5
A.dbb'^
/** 'W yWO^Bdk
* 获得本页的开始编号,为 (p-1)*num+1 C4P<GtR9
*/ 0bT[05.
publicint getStart(){ KIag(!&
return(p - 1) * num + 1; Wpi35JrC
} X2rKH$<g
] _5b
/** 3 yy5 l!fv
* @return Returns the results. D79:L:
*/ "WUS?Q
publicList<E> getResults(){ m[74 p
return results; 75lh07
} ^gZ,A]
d7
H *F
public void setResults(List<E> results){ /XEW]/4
this.results = results; JXYZ5&[
} ?Ve IlD
`fTM/"
public String toString(){ ,"XiI$Le
StringBuilder buff = new StringBuilder O#^H.B
d]"4aS
(); 0GXY2+p}S
buff.append("{"); .V?[<}OJn
buff.append("count:").append(count); 8/BMFRJ
buff.append(",p:").append(p); pDSNI2
buff.append(",nump:").append(num); D
fzs A4
buff.append(",results:").append \6JOBR
Xq&BL,lS
(results); 46Sz#^y
P
buff.append("}"); {G VA4=UAE
return buff.toString(); ]|+M0:2?
} 9|#cjHf
kuV7nsXiQ
} ~IS8DW$;
fyA-*)oHv
kMMgY?