Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 te b~KM
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Gr
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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 yt-F2Z&
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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
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分页支持类: P!JRIw
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java代码: yv!,iK9
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package com.javaeye.common.util; 5E#koy7
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import java.util.List; u+RdC;_
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publicclass PaginationSupport { bof{R{3q
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publicfinalstaticint PAGESIZE = 30; s: .5S
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privateint pageSize = PAGESIZE; zFtw Aa =r
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privateList items; gl4|D
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privateint totalCount; %joIe w]V3
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privateint[] indexes = newint[0]; `[+nz
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privateint startIndex = 0; F; IG@ &
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public PaginationSupport(List items, int f'\NGL
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totalCount){ F<UEipe/N
setPageSize(PAGESIZE); 3ppY@_1
setTotalCount(totalCount); |x AwiF_
setItems(items); 3psCV=/z
setStartIndex(0); tN5brf
} Rp 2~d
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public PaginationSupport(List items, int !0g+}
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totalCount, int startIndex){ I!)gXtJA"
setPageSize(PAGESIZE); 1{-W?n
setTotalCount(totalCount); _cZ`7]Z
setItems(items); s'V8PN+-
setStartIndex(startIndex); :95wHmk
} %rQ5 <U
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public PaginationSupport(List items, int *6)u5
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totalCount, int pageSize, int startIndex){ m4@y58n=
setPageSize(pageSize); V;Zp3Qo!
setTotalCount(totalCount); fNi&1J-/
setItems(items); Hy<4q^3$G
setStartIndex(startIndex); ><X!~by
} TA}z3!-y*
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publicList getItems(){ >8V;:(nt
return items; .,K?(O4AY
} ,~Y5vnaOQ
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publicvoid setItems(List items){ $
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this.items = items; G6zFCgFJ^y
} )>ed6A1
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publicint getPageSize(){ @NXGVmY1}
return pageSize; $J#}3;a
} \<VwGbzFi
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publicvoid setPageSize(int pageSize){ Y962rZ
this.pageSize = pageSize; DU7kZ
} o_gpBaWD
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publicint getTotalCount(){ s
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return totalCount; >qn@E?Uf
} R0fZ9_d7}
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publicvoid setTotalCount(int totalCount){ AAsl)
if(totalCount > 0){ P,!k^J3:l
this.totalCount = totalCount; >R?EJ;h
int count = totalCount / 181-m7W
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pageSize; AQ-P3`bCb
if(totalCount % pageSize > 0) d8g3hyI5\
count++; Q=yQEh|Y
indexes = newint[count]; Dd*T5A?
for(int i = 0; i < count; i++){ HPAg1bV:-
indexes = pageSize * -9{}rE
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i; Vzz0)`*hQ
} Yuze9b\[
}else{ bK%go
this.totalCount = 0; 9il!w
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} 4j)Y>
} =L<OTfVE
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publicint[] getIndexes(){ O#7fkL
return indexes; C["^%0lj
} B| %=<1?
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publicvoid setIndexes(int[] indexes){ d
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this.indexes = indexes; C4Q^WU+$j
} #JZf]rtp
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publicint getStartIndex(){ T}2a~
return startIndex; "G|Gyc
} 2?ZHWS>U
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publicvoid setStartIndex(int startIndex){ w"-bO ~5h
if(totalCount <= 0) V/|Ln*rm
this.startIndex = 0; t9m:E
elseif(startIndex >= totalCount) E[LXZh
this.startIndex = indexes gi:;{
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[indexes.length - 1]; uGJeQ
elseif(startIndex < 0) \XMl8G
this.startIndex = 0; Lq
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else{ )TM ![^d
this.startIndex = indexes +:It1`A~]
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[startIndex / pageSize]; 6%ID*
} uGLVY%N
} (7}v}3/
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publicint getNextIndex(){ 8dUwJ"<5
int nextIndex = getStartIndex() + d[rxmEXht
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pageSize; + 7E6U*
if(nextIndex >= totalCount) /D 8cJgH-
return getStartIndex(); jzEimKDE's
else Bi
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return nextIndex; b]Rn Cu"
} 9A3Q&@,
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publicint getPreviousIndex(){ X~G"TT$)
int previousIndex = getStartIndex() - x`%;Q@G
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pageSize; LiQs;$V
if(previousIndex < 0) IwFg1\>
return0; ffm19 B=
else 3=dGz^Zdv:
return previousIndex; gNs@Q!
} 1
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} Ko''G5+
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抽象业务类 IO>Cy o
java代码: A1%V<im@Z
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/** ENJ]
* Created on 2005-7-12 giaO7Qh~
*/ HE+VanY![
package com.javaeye.common.business; c!Pi)
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import java.io.Serializable; kHz3_B9[
import java.util.List; iyH<!>a
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import org.hibernate.Criteria; *i%!j/QDAP
import org.hibernate.HibernateException; 51;(vf
import org.hibernate.Session; do=VPqy
import org.hibernate.criterion.DetachedCriteria; ]X?+]9Fr
import org.hibernate.criterion.Projections; s o~p+]
import |nD2k,S<?
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org.springframework.orm.hibernate3.HibernateCallback; 'Q(A5zfN]Y
import fhfdNmtR)I
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org.springframework.orm.hibernate3.support.HibernateDaoS Cn28&$:J
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upport; e|MyA?`
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import com.javaeye.common.util.PaginationSupport; \3)%p('
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public abstract class AbstractManager extends CF42KNq
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HibernateDaoSupport { Ubn5tN
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privateboolean cacheQueries = false; b> 2u>4
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privateString queryCacheRegion; }clFaT>m?
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publicvoid setCacheQueries(boolean Qr0JJoHT
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cacheQueries){ XkdNWR0
this.cacheQueries = cacheQueries; $AsM 9D<BE
} 3\D jV2t
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publicvoid setQueryCacheRegion(String iNQk{n
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queryCacheRegion){ 1Kc*MS
this.queryCacheRegion = qM1$?U
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queryCacheRegion; +p<Y)Z(>6
} /;.M$}Z>`
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publicvoid save(finalObject entity){ 3tLh{S?uJ
getHibernateTemplate().save(entity); mDV 2vg
} ^Gd<miw
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publicvoid persist(finalObject entity){ n:<avl@o<
getHibernateTemplate().save(entity); {v`wQM[
} CSsb~/Oxu
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); 8o{ SU6pH
} f"-<Z_
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publicvoid delete(finalObject entity){ ;[9cj&7C<
getHibernateTemplate().delete(entity); Y$Uvt_
} },f7I^s|
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publicObject load(finalClass entity, -OkKLub
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finalSerializable id){ o9eK7*D
return getHibernateTemplate().load 9d2$F9]:o
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(entity, id); 4]dPhsey
} m
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publicObject get(finalClass entity, e |4jT7L}
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finalSerializable id){ UoKBcarm
return getHibernateTemplate().get dR=SW0Oa{
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(entity, id); ?2=c'%w7
} ^OQ_iPPI
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publicList findAll(finalClass entity){ ;w6\r!O,
return getHibernateTemplate().find("from u YH{4%
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" + entity.getName()); Y0eu^p)
} 0cS.|\ZTA
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publicList findByNamedQuery(finalString &=7ur
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namedQuery){ m=}kGzIY4
return getHibernateTemplate @wa/p`gj5w
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().findByNamedQuery(namedQuery); RyM2CQg[
} igo7F@_,
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publicList findByNamedQuery(finalString query, ]mqB&{g
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finalObject parameter){ (ZI&'"H
return getHibernateTemplate cdGl[dQ/
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().findByNamedQuery(query, parameter); mV4} -
} Icr'l$PE
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publicList findByNamedQuery(finalString query, MBwp{ET!p
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finalObject[] parameters){ $u"K1Q3
return getHibernateTemplate hB^"GYZ
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().findByNamedQuery(query, parameters); -pjL7/ gx
} b<7.^
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publicList find(finalString query){ 5GRN1Aov<
return getHibernateTemplate().find nC*/?y*9
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(query); > voUh;L
} Z'fy9
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publicList find(finalString query, finalObject f~U|flL^
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parameter){ gT+/CVj R
return getHibernateTemplate().find X F40;urm
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(query, parameter); HmiwpI
} :c.i Z
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public PaginationSupport findPageByCriteria =AAH}
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(final DetachedCriteria detachedCriteria){ -+4$W{OK*0
return findPageByCriteria 0loC^\f
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?IWLl
} TfxKvol'
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public PaginationSupport findPageByCriteria "vJADQ4F
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(final DetachedCriteria detachedCriteria, finalint >\i{,F=U7
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startIndex){ rms&U)?
return findPageByCriteria [AGm%o=)
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(detachedCriteria, PaginationSupport.PAGESIZE, " DFg"
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startIndex); iy4JI,-W
} (;M"'.C
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public PaginationSupport findPageByCriteria WFdS#XfV
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(final DetachedCriteria detachedCriteria, finalint 8<G@s`*
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pageSize, #"OKO6]
finalint startIndex){ :L?zk"0C
return(PaginationSupport) q<UqGj7#
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getHibernateTemplate().execute(new HibernateCallback(){ ^:q(ksssY
publicObject doInHibernate ht-6_]+ME
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(Session session)throws HibernateException { 1`uIjXr(
Criteria criteria = 7oWv'
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detachedCriteria.getExecutableCriteria(session); L\B+j+~
int totalCount = ]x Kmz
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((Integer) criteria.setProjection(Projections.rowCount B\mdOTLQ
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()).uniqueResult()).intValue(); OGVhb>LO1
criteria.setProjection T]myhNk
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(null); -OHG1"/
List items = /U`"|3
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criteria.setFirstResult(startIndex).setMaxResults Vz#cb5:g
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(pageSize).list(); C&SYmYj^c
PaginationSupport ps = }I;W
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new PaginationSupport(items, totalCount, pageSize, '=ZE*nGC
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startIndex); sM4wh_lO
return ps; 9}\T?6?8pX
} BAPi<U'D
}, true); "- Ns1A8
} J>'o,"D
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public List findAllByCriteria(final ;L`'xFo>>
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DetachedCriteria detachedCriteria){ C +IXP
return(List) getHibernateTemplate 'D-imLV<<
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().execute(new HibernateCallback(){ m ;KP
publicObject doInHibernate uaGg8
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(Session session)throws HibernateException { (&B &
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Criteria criteria = b)V[d8IA
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detachedCriteria.getExecutableCriteria(session); Rl)/[T
return criteria.list(); oYF8:PYB
} bZi>
}, true); _S[H:b$?
} (u*]&yk
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public int getCountByCriteria(final QA%GK4F70
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DetachedCriteria detachedCriteria){ 0Icyi#N
Integer count = (Integer) !pN,,H6Y
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getHibernateTemplate().execute(new HibernateCallback(){ mA4v 4z
publicObject doInHibernate 4j | vzyc
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(Session session)throws HibernateException {
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Criteria criteria = a@7we=!
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detachedCriteria.getExecutableCriteria(session); "L,FUo^&
return cVz.ac
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criteria.setProjection(Projections.rowCount ?T^$,1-
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()).uniqueResult(); LJiMtqg
} )O}x&@Q
}, true); 06ueE\@Sg
return count.intValue(); Rub"" Ga
} v-l):TL+=
} a"v D+r7Ol
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用户在web层构造查询条件detachedCriteria,和可选的 \nJrjHA
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1|gEY;Ru
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PaginationSupport的实例ps。 ,wq.C6;&
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ps.getItems()得到已分页好的结果集 ('gjfl
ps.getIndexes()得到分页索引的数组 MAR;k?d
ps.getTotalCount()得到总结果数 :+;F" _
ps.getStartIndex()当前分页索引 pymT-
ps.getNextIndex()下一页索引 Y,0O&'>
ps.getPreviousIndex()上一页索引 9 ROKueP
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /fD)/x
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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 4];NX
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一下代码重构了。 q<7Nz]Td
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我把原本我的做法也提供出来供大家讨论吧: LAr6J
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首先,为了实现分页查询,我封装了一个Page类: #v`G4d
java代码: ?W#! S
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/*Created on 2005-4-14*/ S'A~9+
package org.flyware.util.page; MVTU$
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/** Xu'u"amt
* @author Joa u?aq'
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* B0YY7od
*/ Fc nR}TE
publicclass Page { JL*-L*|Zcl
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/** imply if the page has previous page */ oACE:h9U
privateboolean hasPrePage; #<?j784
ikY=}
/** imply if the page has next page */ pY:xxnE
privateboolean hasNextPage; bG5c~
.t["kaA
/** the number of every page */ Gd'^vqo<
privateint everyPage; E2\)>YF{P
x^SE>dy ?z
/** the total page number */ !,1~:*:
privateint totalPage; iBc(
@EJ
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/** the number of current page */ 8..itty
privateint currentPage; =g&0CFF <
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/** the begin index of the records by the current -nU_eDy
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query */ H%/$Rqg
privateint beginIndex; k1%Ek#5
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X
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/** The default constructor */ hup]Jk
public Page(){ PS6G 7
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} vF*H5\ m<a
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/** construct the page by everyPage xxedezNko
* @param everyPage kDm=Cjxv
* */ z~X] v["d
public Page(int everyPage){ K7y}R%QF
this.everyPage = everyPage; a#mdD:,cF
} $+rdzsf)+/
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/** The whole constructor */ Xe*
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public Page(boolean hasPrePage, boolean hasNextPage, mWigy`V^~
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int everyPage, int totalPage, .!Z.1:YR
int currentPage, int beginIndex){ =si<OB
this.hasPrePage = hasPrePage; >w
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this.hasNextPage = hasNextPage; >u6kT\|^C
this.everyPage = everyPage; iedoL0#
this.totalPage = totalPage; :qnRiK]
this.currentPage = currentPage; {wd.aUB
this.beginIndex = beginIndex; |"ck;.)
} *ZY{^f
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/** M.t5,NJ
* @return L1aN"KGMF
* Returns the beginIndex. T9(~^}_+9
*/ ()P?f ed
publicint getBeginIndex(){ ^^)Pv#[3
return beginIndex; {E@@14]g
} b@,w/Uw[*
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/** kWr*+3Xq
* @param beginIndex 9m8`4%y=
* The beginIndex to set.
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*/ _:TD{ EO$
publicvoid setBeginIndex(int beginIndex){ BI}>"',
this.beginIndex = beginIndex; zf^!Zqn[8z
} ,g/ UPK8K=
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/** 4cs`R+]o
* @return ;B
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* Returns the currentPage. w\85D|u
*/ =WN6Fj`
publicint getCurrentPage(){ [5:F
return currentPage; CjIkRa@!x
} Prr<:q
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/** \ar.(J
* @param currentPage koaH31Q
* The currentPage to set. ZfMJU
*/ +DVU"d
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; Z\NC+{7k]
} <m9IZIY<
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/** jb77uH_
* @return G*Qk9bk9
* Returns the everyPage. Vrz<DB^-e
*/ #E*jX-JT
publicint getEveryPage(){ EV]exYWB
return everyPage; >6(nW:I0y
} `yc.A%5
3~M8.{
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/** $yOfqr
* @param everyPage Kx#G_N@
* The everyPage to set. nfl6`)oW
*/ Is-Kz}4L
publicvoid setEveryPage(int everyPage){ UD"e:O_
this.everyPage = everyPage; -6Cxz./#yS
} JTdK\A>l
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/** "i9$w\lm
* @return {T=I~#LjMI
* Returns the hasNextPage. 7CNEP2}:R
*/ ]%G[<zD,1
publicboolean getHasNextPage(){ (}bP`[@rX!
return hasNextPage; MYjDO>(_
} |L0 s
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/** y?Fh%%uNr
* @param hasNextPage Z\TH=UA
* The hasNextPage to set. u5%.T0
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*/ Jw9|I)H
publicvoid setHasNextPage(boolean hasNextPage){ 1jQz%^~
this.hasNextPage = hasNextPage; X%39cXM C
} Hn:%(Rg=aW
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/** :*@=px
* @return } fSbH
* Returns the hasPrePage. e,8C}
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*/ Le#bitp
publicboolean getHasPrePage(){ j2tw`*S+
return hasPrePage; :aco$ZNH5
} Qp%kX@Z'
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/** kg+"Ta[9
* @param hasPrePage 5jkW@
* The hasPrePage to set. `W{Ye=|[d#
*/ ^'[Rb!Q8
publicvoid setHasPrePage(boolean hasPrePage){ `P"-9Ue=
this.hasPrePage = hasPrePage; @;Yb6&I;
} F y^!*M-
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/** KJJ8P`Kx
* @return Returns the totalPage. DKYrh-MN
* ,I'Y)SLx
*/ \y#gh95
publicint getTotalPage(){ N\ GBjr-d
return totalPage; 4z?6[Cg<
} %p@A8'b
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/** 0=7C-A1(D
* @param totalPage Xg#Dbf4
* The totalPage to set. e6#^4Y/+`
*/ .2Gn)dZU
publicvoid setTotalPage(int totalPage){ Nqewtn9n
this.totalPage = totalPage; 42
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} =<R77rnY&
>:h
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} rOH8W
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 T3+hxS
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个PageUtil,负责对Page对象进行构造: 2"JIlS;J}7
java代码: ^vJ08gu_W
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/*Created on 2005-4-14*/ f4]nz:2
package org.flyware.util.page; lOcvRF
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import org.apache.commons.logging.Log; V#C[I~l
import org.apache.commons.logging.LogFactory; t9W_ [_a9
Vz51=?75
/** js'*:*7
* @author Joa Xpjk2 [,
* 0.bmVN<
*/ B1J+`R3OX
publicclass PageUtil { x^9W<
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privatestaticfinal Log logger = LogFactory.getLog h"M}Iz~|V?
`N
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(PageUtil.class); p*n$iroy_{
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/** a'XCT@B
* Use the origin page to create a new page P[aB}<1f0
* @param page Vad(PS0
* @param totalRecords ~Og'IRf
* @return IiS1ubNtZ
*/ :n{rVn}G
publicstatic Page createPage(Page page, int `L7 cS
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totalRecords){ enK4`+.7
return createPage(page.getEveryPage(), pA"pt~6
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page.getCurrentPage(), totalRecords); ,k+jx53XV
} _N0x&9S$
q$~S?X5\
/** Fu!:8Wp!(
* the basic page utils not including exception $A8eMJEpL
c;BQ$je}
handler :KMo'pL
* @param everyPage #](ML:!
* @param currentPage U7bG(?k)
* @param totalRecords el5F>)
* @return page E}.cz\!.
*/ ;m@>v?zE
publicstatic Page createPage(int everyPage, int c{s<W}3Ds
**dGK_^T0
currentPage, int totalRecords){ Nbuaw[[iz
everyPage = getEveryPage(everyPage); h9&<-k
currentPage = getCurrentPage(currentPage); 0XvMaQXQF
int beginIndex = getBeginIndex(everyPage, 5rfGMk<
J rYpZ.Nh
currentPage); $bD 3
int totalPage = getTotalPage(everyPage, ;x|4Tm
Js'COO
totalRecords); l?Bv9k.^?
boolean hasNextPage = hasNextPage(currentPage, 3eFD[c%mN
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totalPage); Jel%1'Dc^
boolean hasPrePage = hasPrePage(currentPage); 1h"0B
jQ1~B1(
returnnew Page(hasPrePage, hasNextPage, ~ m,z|
everyPage, totalPage, x!]ZVl]
currentPage, hRtnO|Z6
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beginIndex); 6EP5n
} qA
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privatestaticint getEveryPage(int everyPage){ ]'DtuT?Z
return everyPage == 0 ? 10 : everyPage; (gs"2
} gP^'4>Jr
>x(^g~i
privatestaticint getCurrentPage(int currentPage){ mzfj!0zR*
return currentPage == 0 ? 1 : currentPage; Q3_ia5 `O
} {- 7T\mj
FzFY2h;n]B
privatestaticint getBeginIndex(int everyPage, int :q0C$xF
I `p44}D3
currentPage){ b;Q
cBGwKT
return(currentPage - 1) * everyPage; O#CxS/M5
} (E\7Ui0Q
+twJHf_U
privatestaticint getTotalPage(int everyPage, int 'hg, W]
/N{x Ft/?
totalRecords){ eWW\m[k]}
int totalPage = 0; oIQor%z
~Se/uL;*
if(totalRecords % everyPage == 0) FwmE1,
totalPage = totalRecords / everyPage; 2Q-kD?PO,
else `+k&]z$m
totalPage = totalRecords / everyPage + 1 ; \CX`PZ><
adHHnH`,
return totalPage; H:a(&Zb
} r6*0H/*
rqT@i(i
privatestaticboolean hasPrePage(int currentPage){ #eR*|W7o
return currentPage == 1 ? false : true; _lu.@IX-
} GriL< =?t
`cMa Fc-y/
privatestaticboolean hasNextPage(int currentPage, kplyZ
+8mfq\Y1
int totalPage){ )u(`s `zd
return currentPage == totalPage || totalPage == HVh+Zk
mY
|$=n5X
0 ? false : true; zA\DI]:+
} %(,JBa:G
Z\4l+.R`
E.}T.St
} 6*tI~
\62|w HX
"72
_Sw
^#vWdOlt
C(xdiQJh
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。 Qm^N}>e
ZYc)_Og
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 \; $j
"i&
!!DHfAV]
做法如下: Ko kmylHu
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <G}>Gk8x
'!b1~+PV
的信息,和一个结果集List: Nq9@^ E-{M
java代码: KZsSTB6J
{CYFM[V
E{(7]Wri
/*Created on 2005-6-13*/ pN1W|Wv2
package com.adt.bo; xzAyE5GL>
{LrezE4
import java.util.List; &5~bJ]P
}Q/xBC)
import org.flyware.util.page.Page; JY4 +MApN
QE m6#y
/** Z_ak4C
* @author Joa #e{l:!uS\
*/ bCy.S.`jHQ
publicclass Result { F3;UH%L1
:
v<|y F
private Page page; 3{]csZvW
6- s/\
private List content; g.iiT/b
D-69/3 PvP
/** [
!].G=8
* The default constructor 6rq:jvlx$
*/ ;[uJ~7e3
public Result(){ bX=A77
super(); Rm&i"
} 3K_J"B*7
h/QZcA
/** 65)/|j+
* The constructor using fields *)T},|Gc
* ys u"+J
* @param page l)4KX{Rz{A
* @param content Jx.Jx~
*/ "tn]s>iAd=
public Result(Page page, List content){ pbl;n|
this.page = page; E&7U |$
this.content = content; l]uF!']f
} 5)AMl)
&Plc
/** [y W0U:m
* @return Returns the content. xbvZ7g^
*/ ?FA} ;?v
publicList getContent(){ J
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return content; BwEO2a{
} ~]O~a}]g(
Cevl#c5p>
/** W{*U#:Jx1
* @return Returns the page. wC}anq>>
*/ &) T5V
public Page getPage(){ J)"2^?!&B
return page; l*e*jA_>:7
} a[1^)=/DM
ToTehVw
/** 9B{,q6
* @param content wJNiw)C
* The content to set. -2{NI.-Xd
*/
+ZQf$@+
public void setContent(List content){ pW 2NrBq@w
this.content = content; b>er 'U
} 9l]+rs+
HcavA{H
/** -B* = V
* @param page &z+nNkr?yN
* The page to set. +? E~F
*/ '-N `u$3Y
publicvoid setPage(Page page){ N^*%{[<5
this.page = page; 7;2j^qPr
} <v>^#/.0
} )+OI}
+C' u!^)
>7V96jL$Y
^Vso`(Ss
!KKkw4
2. 编写业务逻辑接口,并实现它(UserManager, =\"88e;b2
V|gW%Z,j
UserManagerImpl) >B!E 6ah
java代码: ,.A@U*j
>-*rtiE
7l/.fSW
/*Created on 2005-7-15*/ 7/&i'y
package com.adt.service; 3LN+gXmU
@tGju\E"o
import net.sf.hibernate.HibernateException; 7jL+c~
ePv3M&\J
import org.flyware.util.page.Page; WXV (R,*Tc
c@7d4Jz
import com.adt.bo.Result; q^; SZ^yW5
)CJXkzOX
/** -d1 YG[1|
* @author Joa zl^ %x1G
*/ &kUEnwQ-
publicinterface UserManager { duFVh8
=PYfk6j9
public Result listUser(Page page)throws =.a}
RtO3!dGT.
HibernateException; [
R
b
5<&hN4g
} /Jj7+?
c!*yxzs\
kw{dvE\K
1y'8bt~7Pf
C~-x637/
java代码: ]9qY(m
js;p7wi
o@:${>jw
/*Created on 2005-7-15*/ Heh.CD)Q
package com.adt.service.impl; xY4g2Q
J
@+Yql
import java.util.List; SQ'\K d=
,.DTJ7H+
import net.sf.hibernate.HibernateException; E:vgG|??
H1>~,zc>E
import org.flyware.util.page.Page; {*mf Is
import org.flyware.util.page.PageUtil; 7+
+Fak
-Pt.
import com.adt.bo.Result; \]<eLw-v
import com.adt.dao.UserDAO; *U>"_h T0
import com.adt.exception.ObjectNotFoundException; @n2Dt d
import com.adt.service.UserManager; fE`p
: N9,/-s
/** E+z),"QA
* @author Joa + OKk~GYf
*/ k;/K']4y
publicclass UserManagerImpl implements UserManager { TWE>"8]
J;HYGu:
private UserDAO userDAO; I\e/
Bv^
=r|e]4
/** idsBw!DB
* @param userDAO The userDAO to set. )|3BS`
*/ B|d-3\sn
publicvoid setUserDAO(UserDAO userDAO){ dynkb901s
this.userDAO = userDAO; {=K);z
} zVt1Ta:j
lCafsIB
/* (non-Javadoc) `A\,$(q+
* @see com.adt.service.UserManager#listUser h4p<n&)F
'3<T~t
(org.flyware.util.page.Page) Z9wKjxu+
*/ Fi+8| /5
public Result listUser(Page page)throws ^AhV1rBB
~:FF"T>
HibernateException, ObjectNotFoundException { xVxN
@[
int totalRecords = userDAO.getUserCount(); #qLsAw--Q
if(totalRecords == 0) mrmm@?
throw new ObjectNotFoundException |\.:h":!0~
Me 5Xd|
("userNotExist"); RN^<bt{_U
page = PageUtil.createPage(page, totalRecords); K*R
List users = userDAO.getUserByPage(page); -al\*XDz
returnnew Result(page, users); '+EtnWHs
} '/="bSF
hY5GNYDh
} i~3\jD=<
^4/
cN% r\
1;v,rs M
L|hELWru
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 '4KN
'p FK+j
询,接下来编写UserDAO的代码: :+_uyp2V
3. UserDAO 和 UserDAOImpl: E] 6]c!2:
java代码: QM('bbN
1.0:
`T\_Wje(
/*Created on 2005-7-15*/ bv^wE,+?o
package com.adt.dao; f9K+o-P.h
7D(Eo{ue
import java.util.List; KvjsibI/Y
S>Z07d6 &
import org.flyware.util.page.Page; g^l~AR
E3hXs6P
import net.sf.hibernate.HibernateException; ~P7zg!p/q
[][ze2+b
/** E"%dO
* @author Joa |LV}kG(2
*/ *I:a\o~$[
publicinterface UserDAO extends BaseDAO { )\KU:_l
~xLo0EV"
publicList getUserByName(String name)throws oRo[WQla
~4+ICCbH
HibernateException; ]z O6ESH
u>ZH-nw O
publicint getUserCount()throws HibernateException; F MX^k
,ZI#p6
publicList getUserByPage(Page page)throws |A.nP9 hW
dVMduo
HibernateException; S
awf]/
:F8h}\a*
} \G0YLV~>P
|.z4 VJi4
{uDH-b(R
qTrM*/m:]L
8-_atL
java代码: .],:pL9d
*Sg6VGP
){LU>MW{&
/*Created on 2005-7-15*/ HvR5-?qQ
package com.adt.dao.impl; XuoyB{U
;V?3Hwl
import java.util.List; 2FN E ;y(
$D='NzE/
import org.flyware.util.page.Page; *ESi~7;#
]GT+UX
import net.sf.hibernate.HibernateException; DH7]TRCMZ)
import net.sf.hibernate.Query; tmd{Gx}c
C{:U<q
import com.adt.dao.UserDAO; q`VkA
\
j[,XJ,5=
/** 5g%D0_e5
* @author Joa y@@h )P#
*/ ( Sjlm^bca
public class UserDAOImpl extends BaseDAOHibernateImpl z }Lf]w?
Y[N@ )E_G
implements UserDAO { 6u'E}hAx|
-d9L
/* (non-Javadoc) rf^u&f
* @see com.adt.dao.UserDAO#getUserByName u9{SG^
s)jNP\-
(java.lang.String) `PZ\3SC'i
*/ F}.R-j#
publicList getUserByName(String name)throws q[Tl#*P?y
cA+T-A]
HibernateException { QFK'r\3pU
String querySentence = "FROM user in class p//mVH%
Mtl`A'KQ/K
com.adt.po.User WHERE user.name=:name"; AC\y|X8-
Query query = getSession().createQuery DUSQh+C
? o&goiM
(querySentence); v^J']p
query.setParameter("name", name); ]UkqPtG;
return query.list(); ^6gEL~m|]
} t3 3\f<e
n%;4Fm?
/* (non-Javadoc) s{OV-H
* @see com.adt.dao.UserDAO#getUserCount() `z`=!1
*/ `,O"^zR)z
publicint getUserCount()throws HibernateException { VnqcpJ
int count = 0; ?E,-P!&R
String querySentence = "SELECT count(*) FROM Q,M,^_
8`s*+.LI!
user in class com.adt.po.User"; P v=]7>e
Query query = getSession().createQuery f9OY>|a9
*kTj,&x[
(querySentence); g*Pn_Yo[.
count = ((Integer)query.iterate().next 2%v6h
p' 6h9/
()).intValue(); 6B]i}nFH{+
return count; f,kV
} )gz]F_
_R^ZXtypd
/* (non-Javadoc) aeVd.`lxM
* @see com.adt.dao.UserDAO#getUserByPage '9'f\
/oZvm
(org.flyware.util.page.Page) 9@?|rje9
*/ b'C#]DorE
publicList getUserByPage(Page page)throws ~1XC5.*-
nI4oQE
HibernateException { z0x^HDAeC
String querySentence = "FROM user in class (/^?$~m"
GPizR|}h
com.adt.po.User"; k%8kt4\wn6
Query query = getSession().createQuery M;W&#Fz%
v-8{mK`9\
(querySentence); ([|^3tM
query.setFirstResult(page.getBeginIndex()) ~;-2eKw
.setMaxResults(page.getEveryPage()); ~c55LlO>
return query.list(); ~Y{]yBGoF
} Lr20xm
7L!}F;yT
} 0$NzRPbH
nTw:BU4jd
PT~F^8,)
oB @)!'
cuI&Q?+c}
至此,一个完整的分页程序完成。前台的只需要调用 A6+qS
[
X40JCQx{+
userManager.listUser(page)即可得到一个Page对象和结果集对象 1;?w#/&t
VU6+"2+'2
的综合体,而传入的参数page对象则可以由前台传入,如果用 }8ESp3~e_
_+)n}Se
webwork,甚至可以直接在配置文件中指定。 mKE'l'9A_
oKr= ]p
下面给出一个webwork调用示例: Unansk
java代码: $m-C6xC/
C8i4z
K47.zu
/*Created on 2005-6-17*/ ,<C~DSAyZ
package com.adt.action.user; [vz2< genn
h#Mx(q
import java.util.List; C?MKbD=K
zlB[Eg^X
import org.apache.commons.logging.Log; ny!80I
import org.apache.commons.logging.LogFactory; ,-kz\N@.
import org.flyware.util.page.Page; M04u>|
,
IF@vl
import com.adt.bo.Result; =*.S<Ko)
import com.adt.service.UserService; /cVZ/"
import com.opensymphony.xwork.Action; vR pO0qG
gv&Hu$ca
/** >s!k"s,
* @author Joa Y9
Bk$$#\
*/ xT( pB-R
publicclass ListUser implementsAction{
z).&0K
fh66Gn,
privatestaticfinal Log logger = LogFactory.getLog \F\xZ.r
Gm> =s
(ListUser.class); I~E&::,
|Om9(xT
private UserService userService; D><^ 7nr%
X{[$4\di{
private Page page; ug'^$geM
9
&Ry51
privateList users; kpy)kS
/!.]Y8yEH
/* GO*D4<#u
* (non-Javadoc) In;P33'p
* XF>!~D
* @see com.opensymphony.xwork.Action#execute() 5Q:49S47
*/ >]A#_p
publicString execute()throwsException{ >6W #v[
Result result = userService.listUser(page); 7Bd=K=3u
page = result.getPage(); n
4cos
users = result.getContent(); D(Q]ddUi'
return SUCCESS; Lo Y*,Aa&
} ~Y;Z5e=
_;/+8=
/** (]VY==t~
* @return Returns the page. 7VdxQ T
*/ ] yWywa\
public Page getPage(){ D{qr N6g#
return page; ZN&9qw*
} A;6ew4
) 3V1aC
/** .eorwj]yb
* @return Returns the users. )cL`$h4DD
*/ 8A/rkoht*
publicList getUsers(){ P)hGe3
return users; d/ @P;YN!
} -i_XP]b&
jLY$P<u?%P
/** f)V6VNW.3
* @param page yMmUOIxk\
* The page to set. DMSC(Sz
*/ ;#8xRLW
publicvoid setPage(Page page){ b.8T<@a
this.page = page; YY$Z-u(
} ,Ij/
^EC}
??LE0i
/** [@3.dd
* @param users b`Jsu!?{
* The users to set. W59 xe&l
*/ :QHh;TIG=<
publicvoid setUsers(List users){ ,g3n/'rP%
this.users = users; !/!Fc'A
} E8wkqZN
&Z9rQH81f>
/** Po.by~|
* @param userService e?
|4O<@
* The userService to set. !CY*SGO
*/ W'Y(@
publicvoid setUserService(UserService userService){ !9.\A:G
this.userService = userService; "5Z5x%3I
} vIZFI
} lS!O(NzqE'
o3NB3@uj<
`=Bv+
u@`y/,PX
IJ:JH=8
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, V@EyU/VJ
5yj6MaqJ
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 .ezZ+@LI+#
*Uf>Xr&
么只需要: hM=X#
;
java代码: ER}5`*X{
d69dC*>
M6V^ur 1
<?xml version="1.0"?> Kw:%B|B<T
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork /1bQ
RI^\
9A|9:OdG1
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )t:8;;W@Ir
2r]o>X
1.0.dtd"> :2XX~|
sv#b5,>9
<xwork> s"2+H}u
WY5HmNX3E
<package name="user" extends="webwork- i'1MZ%.
I=
cayR
interceptors"> %ZDO0P !/
sWKdqs
<!-- The default interceptor stack name =8"xQ>D62
r029E-
--> 0< }BSv
<default-interceptor-ref ,,Ivey!kL
YOA)paq+
name="myDefaultWebStack"/> Ka%#RNW
i.KRw6
<action name="listUser" Qv]rj]%
hDBo
XIK
class="com.adt.action.user.ListUser"> QR<<O
<param `}FZ;q3DP
/*GCuc|
name="page.everyPage">10</param> R:f ,g2
<result m9-=Y{&/
kP^=
name="success">/user/user_list.jsp</result> O3#eQs
</action> o]GZq..
I\Cg-&e
</package> j6L (U~%
O.8k [Ht
</xwork> 1?Tj
H!l9a
: JSuC
T#[#w*w/
R D?52\
A!}Ps"Z
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 i|28:FJA
9kbczL^Y
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。 6fCHd10!
}'n]C| gZ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 2R;#XmKS
x,fL656t
WSGho(\
0Fsa&<{6?
.S4%Q9l
我写的一个用于分页的类,用了泛型了,hoho k-)Ls~#+
2h)Qz+|7
java代码: }KEr@h,N
(Ap?ixrR_
)#`&[9d-
package com.intokr.util; bU/YU0ZIT
;krIuk-
import java.util.List; h
R6Pj"@0
Ry? f; s
/** iqN?'8
* 用于分页的类<br> ^ohIJcI-
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ksUF(lYk
* #]Jg>
* @version 0.01 }d5~w[
* @author cheng O]Yz7
*/ r@
!
public class Paginator<E> { H?V
b
privateint count = 0; // 总记录数 6)>otB8)J
privateint p = 1; // 页编号 ofPv?_@
privateint num = 20; // 每页的记录数 rZ2cC#
privateList<E> results = null; // 结果 _6g(C_m'T?
s=556
/** ?},RN
* 结果总数 $ ?|;w,%I
*/ =hY/Yr%P
publicint getCount(){ U*go}dt"5
return count; I~;H'7|e
} KleiX7
5Yww,s
publicvoid setCount(int count){ oY7jj=z#T
this.count = count; *.Z~f"SZy*
} 6qWWfm/6
,zxv>8Nt
/** \Pe+]4R-Xo
* 本结果所在的页码,从1开始 P4+PY 8
* X}g3[
* @return Returns the pageNo.
,,BWWFg~
*/ `;j$]
publicint getP(){ 3e1P!^'\
return p; w"?RbA
} : LT'#Q8
TOG:N~
/** !0F+qzGG7
* if(p<=0) p=1 tg\o"QKW9
* *dPbV.HCl
* @param p b[:{\!I
*/ _KkP{g,Y
publicvoid setP(int p){ &:1q3gDm
if(p <= 0) usC$NVdm
p = 1; '}"&JO~vPj
this.p = p; S0}=uL#dt
} \1QY=}
*kEzGgTzoS
/** 'K#ndCGJ$
* 每页记录数量 %joL}f[
*/ <Y$(
lszT
publicint getNum(){ )V&hS5P=S
return num; Cl{Ar8d}
} \k^ojz J
8 VhU)fY
/** `3@?)xa
* if(num<1) num=1 l,zhBnD
*/ h[Uo6`
publicvoid setNum(int num){ <1
;pyw
y
if(num < 1) e+MQmWA'F
num = 1; n=|% H'U
this.num = num; C7DwA/$D
} <XN=v!2;
NCl@C$W9q
/** d`~~Ww1
* 获得总页数 -:OJX #j
*/ FZLx.3k4
publicint getPageNum(){ c] t@3 m
return(count - 1) / num + 1; ?Ygd|a5
}
Lw%_xRn)
[^^ Pl:+
/** $48Z>ij?f
* 获得本页的开始编号,为 (p-1)*num+1 )4m`Ya,E3
*/ &HtTh {
publicint getStart(){ 0%4OmLBT
return(p - 1) * num + 1; ]hoq!:>M1
} k+vfZ9bD(J
m/ID3_
/** k[,0kP;
* @return Returns the results. VqxK5
*/ K<kl2#
publicList<E> getResults(){ G=SMz+z
return results; 76KNgV)3
} ={+8jQqi1
9C0#K\
public void setResults(List<E> results){ 5$+ssR_?k
this.results = results; |(.%`BTD
} OA(.&5]
vm'Z A7f6
public String toString(){ CPMGsW^
StringBuilder buff = new StringBuilder '4Fwh]Ee
9y<h.T
(); -4zV
yW
S<
buff.append("{"); L"n)fe$
buff.append("count:").append(count); " 0m4&K(3,
buff.append(",p:").append(p); h9#)Eo
buff.append(",nump:").append(num); z^z`{B
buff.append(",results:").append /,UnT(/k(
P.QF9%
(results); ~QDM
.5
buff.append("}"); Hmt2~>FI[
return buff.toString(); MU(I#Prpe
} -; J6S
wy0?*)~
} #V%98|"
RS
l*u[fB
M.r7^9 P