Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @R5jUPUVV
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }!5x1F!
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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 P87!+pB(
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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 |WopsV
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分页支持类: I)xB I~x
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java代码: r/X4Hy0!lT
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package com.javaeye.common.util; >m}U|#;W
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import java.util.List; vv2N;/;I
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publicclass PaginationSupport { AL%gqt]
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publicfinalstaticint PAGESIZE = 30; U
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privateint pageSize = PAGESIZE; i6"/GSA
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privateList items; [}7j0&
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privateint totalCount; 6^W6As0
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privateint[] indexes = newint[0]; +Zaew679
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privateint startIndex = 0; \hjGw,d
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public PaginationSupport(List items, int R&w2y$
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totalCount){ |G2hm8
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setPageSize(PAGESIZE); pK)*{fC$`
setTotalCount(totalCount); p^2"g~
setItems(items); i\P?Y(-{
setStartIndex(0); - nWs@\
} :NB,Dz+i
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public PaginationSupport(List items, int XA
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totalCount, int startIndex){ 64Ot`=A"
setPageSize(PAGESIZE); lpW|GFG
setTotalCount(totalCount); h)%}O.ueB
setItems(items); Wvhg:vup
setStartIndex(startIndex); .g CC$
} x^UE4$oo
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public PaginationSupport(List items, int G1;.\ i
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totalCount, int pageSize, int startIndex){ b&LfL$
setPageSize(pageSize); G2FP|mf,
setTotalCount(totalCount); U Ox$Xwp5&
setItems(items); oDyrf"dl
setStartIndex(startIndex); -Cb<T"7
} aR }|^ex
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publicList getItems(){ ryz
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return items; #z|\AmZ\
} ~[@Gj{6p0
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publicvoid setItems(List items){ e=11EmN9
this.items = items; sGNVZx
} dg%Orvuz
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publicint getPageSize(){ _9Pxtf
return pageSize; wi#]*\N\9
} -*[?E!F
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publicvoid setPageSize(int pageSize){ +/ A`\9QT
this.pageSize = pageSize; tK<GU.+
} 9/lCW
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publicint getTotalCount(){ @PXb^x#k
return totalCount; G)(\!0pNZ
} 4<S*g u*W
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publicvoid setTotalCount(int totalCount){ ;().
if(totalCount > 0){ 5xZ *U
this.totalCount = totalCount; u$%>/cv
int count = totalCount / ,`7;S,f
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pageSize; <1(:W[M
if(totalCount % pageSize > 0) j @c
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count++; M@a?j<7P,m
indexes = newint[count]; zu<8%
for(int i = 0; i < count; i++){ 1Aq*|JSk(
indexes = pageSize * )7mX]@
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} SrV+Ox
}else{ ;H#'9p ,2
this.totalCount = 0; lFWN[`H
} P) fv:a
} b\zRwp
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publicint[] getIndexes(){ \Vis
return indexes; &"dT/5}6
} KKm0@Y
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publicvoid setIndexes(int[] indexes){ gf]biE"k
this.indexes = indexes; ({3hX"C@Q
} "7R"(.~>
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publicint getStartIndex(){ @l9qH1
return startIndex; 0NLoqq
} <BIj
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publicvoid setStartIndex(int startIndex){ $or?7 w>
if(totalCount <= 0) }i1p&EN^
this.startIndex = 0; [/#c9RA
elseif(startIndex >= totalCount) t<O5_}R%d
this.startIndex = indexes w=I'
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[indexes.length - 1]; p*10u@,
elseif(startIndex < 0) qC9$xIWq
this.startIndex = 0; ^/K\a
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else{ j(|G) F
this.startIndex = indexes 9Vx2VjK2'
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[startIndex / pageSize]; Bcx-t)[
} n{F$,a
} ~mc7O
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publicint getNextIndex(){ iw6qNV:\Z
int nextIndex = getStartIndex() + @%L4^ms
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pageSize; )^UM8
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if(nextIndex >= totalCount) \H$Ps9Xh
return getStartIndex(); !dfc1 UjB
else *|MHQp'A
return nextIndex; V\zf yH\~
} Wvl>i HB
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - @R=gJ:&a
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pageSize; :.!]+#Me
if(previousIndex < 0) JGPLVw
return0; >=hOjV;
else BM*9d%m^
return previousIndex; #LlHsY530N
} >:M3!6H_~{
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抽象业务类 Ghgx8 ]e
java代码: gnmKh>0@6o
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/** Y|J\,7CM
* Created on 2005-7-12 g(t"+
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*/ &| %<=\
package com.javaeye.common.business; .lfKS!m2
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import java.io.Serializable; IM&2SSmYNH
import java.util.List; 3vPb}
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import org.hibernate.Criteria; SU;PmG4
import org.hibernate.HibernateException; <v;;:RB6c
import org.hibernate.Session; #%k!`?^fbK
import org.hibernate.criterion.DetachedCriteria; *6~ODiB
import org.hibernate.criterion.Projections; F)/}Q[o8
import @-bX[}.
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org.springframework.orm.hibernate3.HibernateCallback; C.V")D=
import zyTP|SXk
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org.springframework.orm.hibernate3.support.HibernateDaoS fk)ts,p?
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upport; ~vnG^y>%
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import com.javaeye.common.util.PaginationSupport; LtKiJ.j?A
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public abstract class AbstractManager extends 7
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HibernateDaoSupport { vlth\[
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privateboolean cacheQueries = false; 9^h\vR|]S
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privateString queryCacheRegion; <`*}$Zh
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publicvoid setCacheQueries(boolean an^"_#8DA@
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cacheQueries){ `;b@a<Wl
this.cacheQueries = cacheQueries; {4Y@DQ-
} `O(ec
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publicvoid setQueryCacheRegion(String 2#l<L>#
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queryCacheRegion){ T6JN@:8
this.queryCacheRegion = 'M185wDdAl
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queryCacheRegion; LAeJz_9U
} VTySKY+
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publicvoid save(finalObject entity){ ^D\1F$AjC
getHibernateTemplate().save(entity); xc[@lr
} IW3ZHmrpA
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publicvoid persist(finalObject entity){ 4k_&Q?1
getHibernateTemplate().save(entity); 5bM/
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} Zpg/T K
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publicvoid update(finalObject entity){ !Uz{dFJf;
getHibernateTemplate().update(entity); 3}=r.\]U
} :S}!i?n
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publicvoid delete(finalObject entity){ 1C\OL!@L
getHibernateTemplate().delete(entity); D_
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} lxy_O0n
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publicObject load(finalClass entity, t
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finalSerializable id){ 84^'^nd
return getHibernateTemplate().load cjt<&b*
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(entity, id); 'HTr02riY
} <l]P
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publicObject get(finalClass entity, YO7Y1(`
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finalSerializable id){ D-e0q)RSU
return getHibernateTemplate().get fyPpzA0
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(entity, id); #j
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} sS;6QkI"y
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publicList findAll(finalClass entity){ CY#|VE M
return getHibernateTemplate().find("from /y lO["<Q
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" + entity.getName()); )o)<5Iqh
} D7|[:``
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publicList findByNamedQuery(finalString nmZz`P9g
<<`*o[^L
namedQuery){ :;W[@DeO[
return getHibernateTemplate B.CUk.
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().findByNamedQuery(namedQuery); E^w2IIw
} ifj%!*
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publicList findByNamedQuery(finalString query, H"czF
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finalObject parameter){ RUqN,C,m5I
return getHibernateTemplate i'9aQi"G
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().findByNamedQuery(query, parameter); <WFA3
} G n"]<8yl~
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publicList findByNamedQuery(finalString query, 2g5i3C.q$
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finalObject[] parameters){ $U%M]_
return getHibernateTemplate Z-|.j^n
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().findByNamedQuery(query, parameters); Oxs O
} }a?PBo`
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publicList find(finalString query){ li'h&!|]
return getHibernateTemplate().find c'cK+32
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(query); +v.uP [H
} {<&i4;
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publicList find(finalString query, finalObject MCOiB<L6
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parameter){ Cbu/7z
return getHibernateTemplate().find &_Kb;UVRj
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(query, parameter); -!MrG68
}
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public PaginationSupport findPageByCriteria m(CW3:|
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(final DetachedCriteria detachedCriteria){ d 90
return findPageByCriteria gGF]Dq
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); )_bc:6Q
} TNe,'S,%
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public PaginationSupport findPageByCriteria MzjV>.
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(final DetachedCriteria detachedCriteria, finalint 9U[Gh97Sf
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startIndex){ zVN/|[KP4
return findPageByCriteria DfYOGs]@
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(detachedCriteria, PaginationSupport.PAGESIZE, Gk_%WY*
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startIndex); pde,@0(Fa
} \7b-w81M-
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public PaginationSupport findPageByCriteria ZK:dhwer
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(final DetachedCriteria detachedCriteria, finalint g4b-~1[S
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pageSize, l-s%3E3
finalint startIndex){ PPoQNW
return(PaginationSupport) k=;>*:D%
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getHibernateTemplate().execute(new HibernateCallback(){ kc*zP=
publicObject doInHibernate )Z6bMAb0'N
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(Session session)throws HibernateException { \8j5b+
Criteria criteria = !ieMhJ5r
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detachedCriteria.getExecutableCriteria(session); i%BrnjX
int totalCount = +c)"p4m
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((Integer) criteria.setProjection(Projections.rowCount x_za
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()).uniqueResult()).intValue(); ;+v5li
criteria.setProjection x)evjX=q
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(null); M)v\7a
List items = n(X {|?
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criteria.setFirstResult(startIndex).setMaxResults 2P\k;T(
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(pageSize).list(); R&oC9<
PaginationSupport ps = #'`!*VI
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new PaginationSupport(items, totalCount, pageSize, tG8)!
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startIndex); 5x$/.U
return ps; `O~NT'Ed8
} Mc8|4/<Z
}, true);
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} R Lnsy,
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public List findAllByCriteria(final eKRslMa
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DetachedCriteria detachedCriteria){ /zt9;^e
return(List) getHibernateTemplate \9;SOA v
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().execute(new HibernateCallback(){ Q6>7{\8l
publicObject doInHibernate #Z;6f{yWf
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(Session session)throws HibernateException { 6yDj1PI
Criteria criteria = ,m4M39MWJ
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detachedCriteria.getExecutableCriteria(session); Q1ox<-
return criteria.list(); 7RXTQ9BS
} ~\vGwy
}, true); \VY!= 9EV
} n oWjZ
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public int getCountByCriteria(final |E{tS,{OhJ
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DetachedCriteria detachedCriteria){ FEOr'H<3x
Integer count = (Integer) L >*
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getHibernateTemplate().execute(new HibernateCallback(){ 9gu$vF]9!
publicObject doInHibernate w$5~'Cbi
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(Session session)throws HibernateException { GUX!kj
Criteria criteria = Gp 8%n
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detachedCriteria.getExecutableCriteria(session); B #o/3
return tKr.{#)
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criteria.setProjection(Projections.rowCount O
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()).uniqueResult(); yQP!Vt^
} `/|S.a#g
}, true); S7|6dwQ&
return count.intValue(); xg:r5Z/|)
} C-wwQbdG/
} D\~s$.6B
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用户在web层构造查询条件detachedCriteria,和可选的 $ 12mS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 YwbRzY-#F
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PaginationSupport的实例ps。 j|6@>T1
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ps.getItems()得到已分页好的结果集 4=;.<
ps.getIndexes()得到分页索引的数组 XwZ~pY ~
ps.getTotalCount()得到总结果数 Z`FEB0$
ps.getStartIndex()当前分页索引 '
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ps.getNextIndex()下一页索引 \>B$x@-wg
ps.getPreviousIndex()上一页索引 t^8ii
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;8|D4+
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 7@[HRr
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一下代码重构了。 /0S2Omh
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我把原本我的做法也提供出来供大家讨论吧: ( M > C
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首先,为了实现分页查询,我封装了一个Page类: >e
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java代码: t)#dR._q
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/*Created on 2005-4-14*/ uTWij4)a
package org.flyware.util.page; y v$@i A
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/** 2H,^i,
* @author Joa sIVVF#0}]
* z%4E~u10
*/ {Df97n%h;
publicclass Page { #
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/** imply if the page has previous page */ NWSm
privateboolean hasPrePage; )aV\=a |A
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/** imply if the page has next page */ }NH\Q$ IU
privateboolean hasNextPage; G}2DZ=&>'
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/** the number of every page */ wgN)*dpuI
privateint everyPage; P#8+GN+bF
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/** the total page number */ QNN*/n
privateint totalPage; n+sV$*wvS
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/** the number of current page */ #5Q?Q~E@
privateint currentPage; "M-zBBY ]
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/** the begin index of the records by the current mJ'Q9x"
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query */ -a[[1
privateint beginIndex; )}Vb+
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/** The default constructor */ K)D5%?D
public Page(){ t PJW|wo
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} hJ)\Vo
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/** construct the page by everyPage =6sA49~M
* @param everyPage =7e|e6
* */ 4 !q4WQ ;
public Page(int everyPage){ ?cZ#0U
this.everyPage = everyPage; 0P+B-K>n
} l[,RA?i
{
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/** The whole constructor */ (TX\vI&
public Page(boolean hasPrePage, boolean hasNextPage, u|.c?fW'3
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int everyPage, int totalPage, "X[sW%# F
int currentPage, int beginIndex){ /Ezx'h3Q
this.hasPrePage = hasPrePage; 2\b 2W_
this.hasNextPage = hasNextPage; x;F^7c1
this.everyPage = everyPage; A89n^@
this.totalPage = totalPage; ]* #k|>Fl
this.currentPage = currentPage; Np.]
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this.beginIndex = beginIndex; @5[9iY
} Tc3~~ X
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/** ?<*mIf:?
* @return RaT_5P H~g
* Returns the beginIndex. hja;d1yH
*/ kPuI'EPK
publicint getBeginIndex(){ un&Z'
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return beginIndex; ~xp(k
} SU`RHAo
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/** TJ5g?#Wul
* @param beginIndex AZHZUd4
* The beginIndex to set. hoLQuh%2%
*/
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publicvoid setBeginIndex(int beginIndex){ YKWiZ
this.beginIndex = beginIndex; z{>p<)h
} 21LJ3rW_
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/** =*[98%b
* @return .{=|N8*py8
* Returns the currentPage. id" -eMwp
*/ w,s++bV;L
publicint getCurrentPage(){ +L]$M)*0&
return currentPage; TV['"'D&i
} cu@i;Hb@
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/** IAlX^6s*
* @param currentPage 1KI,/ H"SY
* The currentPage to set. R.Uwf
*/ O:I"<w 9_1
publicvoid setCurrentPage(int currentPage){ xMpQPTte
this.currentPage = currentPage; /A4^l]H;+3
} S>6f0\F/Y%
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/** c1wP/?|.>
* @return FG6bKvEQm^
* Returns the everyPage. wuV*!oef o
*/ ULJV
publicint getEveryPage(){ Ch;wvoy
return everyPage; c*@#0B
} "R!)"B==
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/** &yabxl_
* @param everyPage e -yL
* The everyPage to set. e Lj1
*/ 4[ .DQ#r
publicvoid setEveryPage(int everyPage){ '=V!Y$tn
this.everyPage = everyPage; rD?G7l<~>_
} q!y6K*
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/** O^L#(8bC
* @return jMAZ4M
* Returns the hasNextPage. sx]kH$
*/ ?nwFc3qw
publicboolean getHasNextPage(){ [#3*R_#8R
return hasNextPage; Rt6(y #dF
} 1[4)Sq?
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/** d$?sS9"8(
* @param hasNextPage oR1HJ2>Z1
* The hasNextPage to set. %Ums'<xJ
*/ e6(Pw20)s
publicvoid setHasNextPage(boolean hasNextPage){ K!cLEG!G
this.hasNextPage = hasNextPage; _[:>!ekx
} )UoF*vC(
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/** *pP&$!bH%
* @return 3%0ShMFP@
* Returns the hasPrePage. {~y,.[Ga
*/ %RS~>pK1
publicboolean getHasPrePage(){ <|kS`y
return hasPrePage; 7%0V ?+]P
} |l#<vw
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/** -V_iv/fmM
* @param hasPrePage s-[v[w'E
* The hasPrePage to set. <=g{E-
*/ S!r,p};
publicvoid setHasPrePage(boolean hasPrePage){ p3q
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this.hasPrePage = hasPrePage; Fs}vI~}
} MKPw;@-
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/** ! !we4tWq
* @return Returns the totalPage. -H+<81"B#
* dW4FMm>|
*/ =U- w!uW
publicint getTotalPage(){ R?E< }\!
return totalPage; #JD:i%
} Q/2(qD; u
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*'($j
/** *)|EWT?,
* @param totalPage \}p!S$`
* The totalPage to set. oWP3Y.
*/ ~B704i
publicvoid setTotalPage(int totalPage){ <{Pr(U*7}
this.totalPage = totalPage; JsA.jqkB
} [zw0'-h.
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} `m_('N
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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 ,Qb(uirl]
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个PageUtil,负责对Page对象进行构造: J4l\
java代码: vS1#ien#
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/*Created on 2005-4-14*/ ^lP;JT?
package org.flyware.util.page; +f"q^R IU
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import org.apache.commons.logging.Log; }1}L&M@
import org.apache.commons.logging.LogFactory; iU1yJ=
+!JTEKHKH
/** 5BAGIO<w
* @author Joa dZ6P)R
* 6Qw5_V^0o
*/ vLT$oiN[c
publicclass PageUtil { +v{g'
|J^}BXW'^)
privatestaticfinal Log logger = LogFactory.getLog wOLA8UYW
^NB\[ &
(PageUtil.class); R[vA%G
fP>~ @^
/** _@L{]6P%V
* Use the origin page to create a new page RqU^Q*/sF
* @param page ?igA+(.
* @param totalRecords p*5QV
* @return P
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*/ Muay6b?
publicstatic Page createPage(Page page, int WXmR{za
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totalRecords){ {?YBJnG}x
return createPage(page.getEveryPage(), 3X:)r<
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page.getCurrentPage(), totalRecords); ~zO>Q4-k
} sBq6,Iu
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/** ZFFKv
* the basic page utils not including exception O =gv2e
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handler D3(rD]c0{
* @param everyPage e anR$I;Yj
* @param currentPage
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* @param totalRecords VOkSR6
* @return page Gv\:Agi
*/ ;^f ;<
publicstatic Page createPage(int everyPage, int u5O`|I@R
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currentPage, int totalRecords){ N?j#=b+D
everyPage = getEveryPage(everyPage); lK"m|Z
currentPage = getCurrentPage(currentPage); $VNj0i. Pr
int beginIndex = getBeginIndex(everyPage, yR$ld.[uf
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currentPage); |6o!]~&e$1
int totalPage = getTotalPage(everyPage, pybE0]
#<o=W#[
totalRecords); 6qK`X
boolean hasNextPage = hasNextPage(currentPage, MG-#p8
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totalPage); p6AF16*f0
boolean hasPrePage = hasPrePage(currentPage); i}=n6
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returnnew Page(hasPrePage, hasNextPage, i1JVvNMQ,
everyPage, totalPage, 0?Bv
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currentPage, >)*0lfxTZ
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beginIndex); <X"_S'O
} 4d63+iM+}
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sw
privatestaticint getEveryPage(int everyPage){ H#:Aby-d}
return everyPage == 0 ? 10 : everyPage; w<SFs#Z
} qq'%9
8s9ZY4_
privatestaticint getCurrentPage(int currentPage){ 'B9q&k%<
return currentPage == 0 ? 1 : currentPage; nw,XA0M3
} P<C=9@`!
zFm:=,9
privatestaticint getBeginIndex(int everyPage, int " 7g\X$
`6RR/~kP(
currentPage){ M97MIku~9
return(currentPage - 1) * everyPage; vX}#wDNP
} <^(>o
MRN=-|fV^
privatestaticint getTotalPage(int everyPage, int :-tMH02c
+[2ep"5H
totalRecords){ 3,^.
int totalPage = 0; S~hoAl"xb/
i5#4@ 4aC
if(totalRecords % everyPage == 0) MG:eI?G/'
totalPage = totalRecords / everyPage; sH51 .JG
else |crm{]7X
totalPage = totalRecords / everyPage + 1 ; 7-VP)|L#G
*X\J[$!
return totalPage; :6jh*,OHZl
} 1!W'0LPM
/N7.|XI.
privatestaticboolean hasPrePage(int currentPage){ :YCB23368"
return currentPage == 1 ? false : true; SsCV}[
} 9?tG?b0
9 GtVcucN
privatestaticboolean hasNextPage(int currentPage, p8(Z{TSv
`5
Iaz
int totalPage){ z#*>u
return currentPage == totalPage || totalPage == Oh5aJ)"D
#c$z&J7e
0 ? false : true; y`\rb<AZ*t
} gTb%c84
.~,=?aq^
-T2w?|
} O"~CZh,:r}
KnC:hus
F% z$^ m-
~cul;bb#
4SJb\R)XK
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 V`m9+<.1 b
Kh7C7[&
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 R1~wzy
,}/6Za
做法如下: Gz:ell$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Slv91c&md,
c2wgJH!g
的信息,和一个结果集List: `+!F#.
java代码: H>F j
bD`h/jYv
#z =$*\u
/*Created on 2005-6-13*/ ]cM,m2^2
package com.adt.bo; r2m&z%N&
\k3EFSm
import java.util.List; 6t4Khiwx
nL+y"O
import org.flyware.util.page.Page; 6z2%/P-'
wwE3N[
/** ?N=`}}Ky-
* @author Joa ;r}yeISf
*/ sBa&]9>m
publicclass Result { |4rqj1*U
.l$U:d
private Page page; O>d
[;Q
sAS[wcOQ
private List content; o>HU4O}
\V
T.bUs
/** hA1p#
* The default constructor L&0aS:
*/ YySo%\d
public Result(){ *uoO#4g~
super(); "KgNMNep
} dP?QPky{9
]GBlads
/** W<:x4gBa
* The constructor using fields <"yL(s^u"
* .'b|pd
* @param page JnLF61
* @param content p8j*m~4B
*/ Muyi2F)j
public Result(Page page, List content){ 7Q9| P?&:z
this.page = page; }$b!/<7FD
this.content = content; y@r g_Paq
} 6+4SMf3
<c$rfjM+JU
/** iKu4s
* @return Returns the content. #,h0K
*/ W3jwc{lj
publicList getContent(){ c7D{^$L9v
return content; 1#9PE(!2
} S$
k=70H
<m~{60{
/** zKT4j1h
* @return Returns the page. [qU`}S2
*/ Dt\rrN:v
public Page getPage(){ 0i>p1/kv
return page; ~ ReX$9
} >[l2KD
1A[(R T]
/**
Vfw H:
* @param content 6!SW]#sD
* The content to set. O8~RfB
*/ L{oG'aK4
public void setContent(List content){ &ET$ca`j#
this.content = content; $Z3{D:-)
} QH_Ds,oH=
v#?;PyeF
/** dZX;k0
* @param page R'8S)'l
* The page to set. 7CH.BY
*/ 3taGb>15
publicvoid setPage(Page page){ ^6J*:(eM
this.page = page; ]Y@_ 2`
} Eihy|p
} "]|7%]
m\70&%v
)Y6\"-M[
{yDQncq'^
33&l.[A"!}
2. 编写业务逻辑接口,并实现它(UserManager, lOM8%{.'_x
eAStpG"*
UserManagerImpl) .osG"cS
java代码: qWf[X'
USaa#s4'
) O&zb_{n
/*Created on 2005-7-15*/ q[9N4nj$<
package com.adt.service; r&IDTS#
DP;:%L}
import net.sf.hibernate.HibernateException; j+e~
tCcN/
t+K1ArQc
import org.flyware.util.page.Page; : ^U>n{
y06xl:iQwF
import com.adt.bo.Result; C_JO:$\rE
Kv)}
/** Fv$A%6;W
* @author Joa PpH
;p.-!d
*/ {rK]Q! yj
publicinterface UserManager { (UCCEQq5
zszmG^W{
public Result listUser(Page page)throws |6;-P&_n
||ugb6q[6B
HibernateException; eiXl"R^
:@a0h
} [!MS1vc;
9dm<(I}
\&~YFj B
RAnF=1[v
1;'-$K`}
java代码: }h1eB~6M
bYZU}Kl;(
_#MKp H
/*Created on 2005-7-15*/ /DP0K
@%
package com.adt.service.impl; 8_o~0lb
|5ge4,}0
import java.util.List; 3rd8mh&l
W;l0GxOxQ
import net.sf.hibernate.HibernateException; qHtIjtt[q
Z}t^i^u
import org.flyware.util.page.Page; 0Lb{HLT
import org.flyware.util.page.PageUtil; luyu7`
,p /{!BX
import com.adt.bo.Result; B?yjU[/R
import com.adt.dao.UserDAO; <1B+@
import com.adt.exception.ObjectNotFoundException; [^7P ]olW
import com.adt.service.UserManager; 42p1P6d
KV8<'g +2?
/** qj `C6_?
* @author Joa |)C*i
*/ Dv
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publicclass UserManagerImpl implements UserManager { _*n
`*"
m
OE!`fd
private UserDAO userDAO; FD&^nJ_{
J#ClQ%
/** qS"#jxc==+
* @param userDAO The userDAO to set. ]T)<@bmL
*/ !d U$1:7
publicvoid setUserDAO(UserDAO userDAO){ t%J1(H
this.userDAO = userDAO; }}ic{931
} */_ 'pt
^\kH^
/* (non-Javadoc) SH#*Lc
* @see com.adt.service.UserManager#listUser -(>Ch>O
,,+4d :8$
(org.flyware.util.page.Page) 8ICV"8(
*/ 6GPI
gPL,
public Result listUser(Page page)throws wW/q#kc
X/90S2=P
HibernateException, ObjectNotFoundException { c8Ud<M .
int totalRecords = userDAO.getUserCount(); ;E[Q/
tr:w
if(totalRecords == 0) V"'PA-z3
throw new ObjectNotFoundException pPag@L
gu%i|-}
("userNotExist"); k3nvML,bv
page = PageUtil.createPage(page, totalRecords); .Gvk5Wn
List users = userDAO.getUserByPage(page); , ,ng]&%i
returnnew Result(page, users); eV/oY1B]<
} Dte5g),R
HyOrAv
<
} UqyW8TCf?
q mv0 LU
$COjC!M
\v5;t9uBZ
,|}mo+rb-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 V=% ;5/
__FEdO
询,接下来编写UserDAO的代码: yN0`JI
3. UserDAO 和 UserDAOImpl: y22DBB8
java代码: W3d+t?28
uwr7 .\7
mo] l_'
/*Created on 2005-7-15*/ EApbaS}Up
package com.adt.dao; 5ya^k{`+ZO
vp.?$(L^@/
import java.util.List; a h_>:x
5%e+@X;j
import org.flyware.util.page.Page; "}`)s_rt
S4[#[w`=
import net.sf.hibernate.HibernateException; _ZFEo< `'
_MLf58
/** "om7 :d
* @author Joa 3)6- S
*/ S*|/txE'~Y
publicinterface UserDAO extends BaseDAO { \!BVf@>p%
1^E5VG1[
publicList getUserByName(String name)throws {jmy:e2
3l41"5Fy&
HibernateException; GGr82)E
2 \}J*0
publicint getUserCount()throws HibernateException; %lWOW2~R
# Q,EL73;
publicList getUserByPage(Page page)throws X<Z(,B
3X1 1Gl
HibernateException; R3l{.{3p2
zxCx2.7
} $7c,<=
uC#@qpzy
/]5*;kO`
M<n'ZDK`W
{srxc4R`
java代码: `&7tADFB
-fmJkI
jVQ89vf
~
/*Created on 2005-7-15*/ w4Df?)Z
package com.adt.dao.impl; G$MEVfd"
3Cc#{X-+
import java.util.List; D\9-/p
UO@K:n
import org.flyware.util.page.Page; \3^ue0
1ONkmVtL
import net.sf.hibernate.HibernateException; gCC7L(1
import net.sf.hibernate.Query; t(-,mw
zU+q03l8Ur
import com.adt.dao.UserDAO; u;-fG9xs
L/exR6M7
/** ,NS*`F[O
* @author Joa ZIc.MNq
*/ C-;w}
public class UserDAOImpl extends BaseDAOHibernateImpl }UB@FRPF
;tZQ9#S
implements UserDAO { ^PezV5(
4fC:8\A
/* (non-Javadoc) ?SElJ?Z
* @see com.adt.dao.UserDAO#getUserByName `HkNO@N[
/B~[,ES@1
(java.lang.String) ?X6}+
*/ ]4en|Aq
publicList getUserByName(String name)throws n"6L\u
XDPgl=~
HibernateException { X(*O$B{
R
String querySentence = "FROM user in class bNVeL$'
w,FPL&{
com.adt.po.User WHERE user.name=:name"; HdI)Z<Krp
Query query = getSession().createQuery 9%iQ~
N\ !
(querySentence); /}m*|cG/
query.setParameter("name", name); D\-\U
E/
return query.list(); o#,^7ln
} yvoz 3_!
8Ejb/W_
/* (non-Javadoc) *1<kYrB
* @see com.adt.dao.UserDAO#getUserCount() iI";m0Ny
*/ Gw$ 5<%sB
publicint getUserCount()throws HibernateException { ~<n.5q%Z
int count = 0; )B0%"0?`8
String querySentence = "SELECT count(*) FROM 0O>ClE~P
~;#}aQYo
user in class com.adt.po.User"; Q'jw=w!|g
Query query = getSession().createQuery e@W+ehx"
m)Kg6/MV.
(querySentence); 4F6aPo2
count = ((Integer)query.iterate().next tj[E!
&~H ed_
()).intValue(); !EhKg)y=
return count; 3wq<@dRv4
} -m%`Di!E
`z0q:ME
/* (non-Javadoc) c:Nm!+5_(
* @see com.adt.dao.UserDAO#getUserByPage 8$
u"92
h7UNmwj
(org.flyware.util.page.Page) N8dxgh!,
*/ ?l^Xauk4Pj
publicList getUserByPage(Page page)throws "
L`)^
&btI#
HibernateException { _o$jk8jOjW
String querySentence = "FROM user in class ~!
-JN}H m
~$g:
com.adt.po.User"; BA]$Fi.Mw
Query query = getSession().createQuery QE\
[EI2
JUpV(p"-r
(querySentence); S*V}1</L
query.setFirstResult(page.getBeginIndex()) Xi98:0<=
.setMaxResults(page.getEveryPage()); 0yI1r7yNB+
return query.list(); hcj}6NXc
} tO3R&"{
)_=2lu3%{
} ~(QfVpRnV=
K8sRan[4}
~I@lsCh
W-n4wIj"
vyIH<@@p7
至此,一个完整的分页程序完成。前台的只需要调用 E>|X'I?r^
*(F`NJ 3
userManager.listUser(page)即可得到一个Page对象和结果集对象 WYUDD_m
M}V!;o<t^
的综合体,而传入的参数page对象则可以由前台传入,如果用 Ic0Y
gVOAB-nw
webwork,甚至可以直接在配置文件中指定。 0<-E)\:[g
4\Y5RfLB_
下面给出一个webwork调用示例: 0+* NHiH
java代码: pi?MAE*f
GT&}Burl/n
7~mhWPzMwB
/*Created on 2005-6-17*/ 7#0buXBg
package com.adt.action.user; sI!H=bp-8
U\Wo&giP[
import java.util.List; tbd=A]B-
tTLg;YjN
import org.apache.commons.logging.Log; ,|({[9jA
import org.apache.commons.logging.LogFactory; kO}&Oi,?
import org.flyware.util.page.Page; xV)[C )6
bx8](cT_
import com.adt.bo.Result; dz] 5s
import com.adt.service.UserService; m0"K^p
import com.opensymphony.xwork.Action; TmQIpeych
pa[/6(
/** ~P1~:AT
* @author Joa P2-&Im`+
*/ {_O!mI*
publicclass ListUser implementsAction{ _5jT}I<k
E^axLp>(I
privatestaticfinal Log logger = LogFactory.getLog 8Y?M:^f~
k2U*dn"9U
(ListUser.class); ?BnU0R_r]
(j&:
private UserService userService; \!-BR0+y;
N]A# ecm
private Page page; (jM0YtrD
[ >O!~
privateList users; ?l0Qi
YA4 D?'
/* T }}2J/sj
* (non-Javadoc) '+PKGmRW
* `<C<[JP:o
* @see com.opensymphony.xwork.Action#execute() 9{toPED
*/ 6Yj{%
G
publicString execute()throwsException{ lM6pYYEq=
Result result = userService.listUser(page); Gmz^vpQ]t
page = result.getPage(); 0@
Y#P|QF
users = result.getContent(); AG N/kx
return SUCCESS; to'7o8Z
} +3)r
szb72
0ns\:2)cEB
/** }Y~Dk]*
* @return Returns the page. Lnr9*dm6q
*/ Iux3f+H
public Page getPage(){ @Jzk2,rI
return page; K3yQ0k
|
} 7zb^Z]
oN7SmP_
/** 2r,
c{Ah@D
* @return Returns the users. 1qRquY
*/ qb>41j9_t
publicList getUsers(){ *NmY]
return users; mlnF,+s
} UerbNz|
`^bP9X_a
/** cm< #zu3~S
* @param page 8>&@"j
* The page to set. XcVN{6-z
*/ qO#3{kW
publicvoid setPage(Page page){ B>,eHXW
this.page = page; EuK}L[Kl
} vrnvv?HPrR
_%w680b'
/** j9p6rD
* @param users i9;
* The users to set. x[(6V'
*/ ?b
(iWq
publicvoid setUsers(List users){ PsC")JS
this.users = users; p}1i[//S
} Bm$|XS3cD
l4bytI{63
/** ig,.>'+l
* @param userService :<QknU}dwy
* The userService to set. d*@T30
*/ e97G]XLR
publicvoid setUserService(UserService userService){ <xI<^r'C9e
this.userService = userService; X?5{2ulrI
} 8 #_pkVQw:
} O=B=0
De?VZ2o9"
X0/slOT
;qshd'?*
`Ij@;=(
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, ^q:-ZgM>
b}[S+G-9W
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 Y6` xb`
1EyN
|m|
么只需要: k# [!; <
java代码: m2(>KMbi
S,#1^S
OW7
<?xml version="1.0"?> Ez3fL&*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork {w@qFE'b
o`bch?]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- F-_u/C]
g6GkA.!X$
1.0.dtd"> %~u]|q<{
^P)f]GQx
<xwork> D|-]<r1"
W__ArV2Z_
<package name="user" extends="webwork- #@R0$x
B
`(jTL
interceptors"> Z(mUU]
\TV
<!-- The default interceptor stack name Rs %`6et}\
LgqQr6y"
--> hlzB
cz*
<default-interceptor-ref nV'1 $L#
V=O52?8
name="myDefaultWebStack"/> spEdq}
e;]tO-Nu
<action name="listUser" [9m3@Yd'
FK%b@/7s~
class="com.adt.action.user.ListUser"> %w;qu1j
<param &V].,12x
Jj4HJ9
name="page.everyPage">10</param> +7_qg
i7:
<result broLC5hbQU
rB>ge]$.
name="success">/user/user_list.jsp</result> >!963>D R
</action> n;g'?z=hy
5ZCu6A
</package> *dl hRa
Fr9/TI
</xwork> w,UE0i9I
Z)?$ZI@
PL/g| ;
bi<<z-q`wJ
M\ATT%b:
{,>G 1>Yv
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 \DB-2*a"
a<cwrDZ
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ]Q^)9uE\D
Cf%
qap#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 YT\`R
=[B\50]
tsXKhS;/w
tl#sCf!c
kAftW
'
我写的一个用于分页的类,用了泛型了,hoho XT7m3M
D"7}&Ry:
java代码: 55S s%$k@
`TrWtSwv
)6"}M;v
package com.intokr.util; K-RmB4WI
Et=Pr+Q{c
import java.util.List; JZ5k3#@e
X9x`i
/** W06aj ~7Z
* 用于分页的类<br> D,#UJPyg
* 可以用于传递查询的结果也可以用于传送查询的参数<br> H$![]Ujq
* ,i>`Urd
* @version 0.01 }7 N6nZj`
* @author cheng = Xgo}g1
*/ "Q?+T:D8|
public class Paginator<E> { *z0!=>(
privateint count = 0; // 总记录数
a_?sJ
privateint p = 1; // 页编号 e3I""D{)[=
privateint num = 20; // 每页的记录数 /jv/qk3i
privateList<E> results = null; // 结果 5.rAxdP
$dC`keQM>9
/** Sd7jd ?#9'
* 结果总数 !=0h*=NOYt
*/ L\Se ,
publicint getCount(){ Dqy`7?Kn
return count; ddHl&+G
} m2]N%Y
09kR2(nsW/
publicvoid setCount(int count){ RQVu~7d[
this.count = count; 3j7FG%\
} b8WtNVd
pH'_k k
/** ^<I(
* 本结果所在的页码,从1开始 >pq~ &)^u
* gOF^?M11x
* @return Returns the pageNo. p9v:T1?
*/ 7=-Yxt
publicint getP(){ 8>KUx]AN
return p; g=Xf&}&=x
} ~\":o:qyc
DDE-$)lf>
/** %>+uEjbT
* if(p<=0) p=1 zPt<b!q
* `Ba]i) !
* @param p :So<N}&
*/ -FZC|[is
publicvoid setP(int p){ fi?4!h
if(p <= 0) FnvpnU",
p = 1; GJ9>i)+h;
this.p = p; yD+4YD
} 0Lo8pe`DH
.NOAp
/** HTQZIm
* 每页记录数量 L(y70T
*/ l=?e0d>O
publicint getNum(){ [LoQYDku
return num; HP# SR';E
} (W}F\P
WZQ2Mi<&1'
/** c'oiW)8;A
* if(num<1) num=1 $ XjijD9R
*/ Tmzbh 9
publicvoid setNum(int num){ 2B_|"J
if(num < 1) t2[/eM.G
num = 1; \VpEUU6^U
this.num = num; gAAC>{Wh
} C4+DZ<pE
U5Hi9fe
/** ]]j^
* 获得总页数 yE}\4_0I/
*/ &8$v~
publicint getPageNum(){ *5)UIRd
return(count - 1) / num + 1; >Hf{Mx{<
} \jfK']P/H
(/:m*x*6
/** U,g8:M
xHK
* 获得本页的开始编号,为 (p-1)*num+1 #Y7jNrxE
*/ O= S[n
publicint getStart(){ ,Lig6Z`
return(p - 1) * num + 1; |ADf~-AY
} "J(M. Y
J!:BCjRdw
/** ?eS;Yc
* @return Returns the results. YBt=8`r
*/ 64B.7S88
publicList<E> getResults(){ kL8rqv^
return results; 9c@M(U@Yh
} w;'XqpP$*|
K_YrdA)6
public void setResults(List<E> results){ 9$)&b\D
this.results = results; JL M Xkcc
} =gVMt
{irc0gI
public String toString(){ 0'o[2,
StringBuilder buff = new StringBuilder <h -)zI
ZJDV'mC}
(); Ema[M5$R
buff.append("{"); qo[[P)tq
buff.append("count:").append(count); ^4`aONydl
buff.append(",p:").append(p); 0qS/>u*
buff.append(",nump:").append(num); sOhn@*X
buff.append(",results:").append Qs1CK;+zU
p:08q
B|uQ
(results); ?%,LZw^[
buff.append("}"); .W{CJh
return buff.toString(); eoiz]L
} 5,Fq:j)MxW
aC1z.?!U
} (L(7)WbH
Z9vMz3^N
-06G.;W\^