Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 UB%Zq1D|t
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ynn:,
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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 0L->e(Vf7u
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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 uD'yzR!]+
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分页支持类: ;v#BguM
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java代码: &xhwx>C`K
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package com.javaeye.common.util; Whoqs_Mm{
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import java.util.List; L{pz)')I
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publicclass PaginationSupport { }~I(e
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publicfinalstaticint PAGESIZE = 30; #%Hk-a=>)#
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privateint pageSize = PAGESIZE; 'SW%EVB
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privateList items; QR+xPY~
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privateint totalCount; 0H$6_YX4A
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privateint[] indexes = newint[0]; -FOn%7r#Y
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privateint startIndex = 0; %fbV\@jDCX
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public PaginationSupport(List items, int <v=$A]K
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totalCount){ 9f(0
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setPageSize(PAGESIZE); \eF_Xk[
setTotalCount(totalCount); ^"dVz.
setItems(items); I45 kPfu
setStartIndex(0); -JKl\ E
} 34*73WxK
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public PaginationSupport(List items, int %>p[;>jW
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totalCount, int startIndex){ ]!c59%f=
setPageSize(PAGESIZE); r5RUgt
setTotalCount(totalCount); J#>)+
setItems(items); a/\SPXQ/9
setStartIndex(startIndex); x5w5xw
} &nV/XLpG
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public PaginationSupport(List items, int |?cL>]t
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totalCount, int pageSize, int startIndex){ *&vlfH
setPageSize(pageSize); 1 5heLnei
setTotalCount(totalCount); ._E 6?
setItems(items); =,BDd$e
setStartIndex(startIndex); {})d}dEC
} ]Cc3}+(s
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publicList getItems(){ lGlh/B%
return items; qnu<"$
} zAW+!C.
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publicvoid setItems(List items){ XnwVK
this.items = items; 7"_m?c8
} zb]e{$q2C
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publicint getPageSize(){ aZ,j1j0p
return pageSize; -lY,lC>{
} m
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publicvoid setPageSize(int pageSize){ H9\,;kM)
this.pageSize = pageSize; "u.'JE;j
} D_N0j{E
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publicint getTotalCount(){ A'tv[Td8,
return totalCount; I!?)}d
} dfA2G<Uc
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publicvoid setTotalCount(int totalCount){ dO1h1yJJ
if(totalCount > 0){ ,Y&7` m
this.totalCount = totalCount; l\/uXP?
int count = totalCount / ~W2Od2p!
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pageSize;
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if(totalCount % pageSize > 0) R?3N><oh*
count++; c
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indexes = newint[count]; j].=,M<dxE
for(int i = 0; i < count; i++){ Gw$Y`]ipy
indexes = pageSize * 4wkmgS
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i; { v [
} Al3*? H&
}else{ s$JO3-)
this.totalCount = 0; {/|tVc63
} ;=UkTn}N?l
} z',f'3+
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publicint[] getIndexes(){ M?d (-en
return indexes; Ihd{tmr<
} o(gV;>I
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publicvoid setIndexes(int[] indexes){ ~<Z7\yS)
this.indexes = indexes; .T1n"TfsGO
} )GKY#O09x9
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publicint getStartIndex(){ n%ypxY0
return startIndex; -l~+cI \2
} P8X59^cJ
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z
publicvoid setStartIndex(int startIndex){ ]&?8l:3-G
if(totalCount <= 0) I&%KOe0
this.startIndex = 0; Eb7GiRT#
elseif(startIndex >= totalCount) "$n ff=]
this.startIndex = indexes =D`:2k~
,
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[indexes.length - 1]; >|pN4FS
elseif(startIndex < 0) a0jzt!ci
this.startIndex = 0; ydTd.`
else{ Sc?q}tt^C
this.startIndex = indexes aF{1V\e
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[startIndex / pageSize]; Ftdx+\O_i&
} %,+&Kl
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} z.~jqxA9
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publicint getNextIndex(){ '-BD.^!!
int nextIndex = getStartIndex() + ,YBe|3
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pageSize; zGwM# -
if(nextIndex >= totalCount) 9DmFa5E
return getStartIndex(); 3=("vR`!
else 1'%n?\OK66
return nextIndex; XFv^jSF
} ]G~Z'fs<(
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publicint getPreviousIndex(){ \b}%A&Ij
int previousIndex = getStartIndex() - y
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pageSize; +}
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if(previousIndex < 0) RB9ZaL\
return0; $>zqCi2tB<
else AqT}^fS
return previousIndex; Khh}flRy
} KJv[z
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} X2E=2tXl`7
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抽象业务类 RgVnx] IF
java代码: D?G'1+RIT~
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/** m7u" awM^
* Created on 2005-7-12 BZ,{gy7g7X
*/ Y[s}?Xu]w#
package com.javaeye.common.business; s`|KT&r
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import java.io.Serializable; p~v0pi
import java.util.List; P9x':I$
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import org.hibernate.Criteria; {mB!mbr
import org.hibernate.HibernateException; 3:>hHQi
import org.hibernate.Session; M }$Td_g
import org.hibernate.criterion.DetachedCriteria; K,,'{j2#f
import org.hibernate.criterion.Projections; qFI19`?8E
import &YBZuq2?
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org.springframework.orm.hibernate3.HibernateCallback; }tQ^ch; Q
import L9]d$ r"
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org.springframework.orm.hibernate3.support.HibernateDaoS (o^?i2)g
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upport; .vie#,la
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import com.javaeye.common.util.PaginationSupport; &(m01
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public abstract class AbstractManager extends Yq'D-$@
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HibernateDaoSupport { S~>R}=
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privateboolean cacheQueries = false; $EL:Jx2<
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privateString queryCacheRegion; agq4Zy
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publicvoid setCacheQueries(boolean :sttGXQX
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cacheQueries){ yY]E~
this.cacheQueries = cacheQueries; ff]fN:}V
} OuKRaZ
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publicvoid setQueryCacheRegion(String .#Z"Sj
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queryCacheRegion){ h^,av^lg^
this.queryCacheRegion = Y ` Z,52
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queryCacheRegion; n(i/jW~0w
} \Yn0|j>
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publicvoid save(finalObject entity){ hZw8*H^tP
getHibernateTemplate().save(entity); < FY%QB)h
} j<R&?*
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publicvoid persist(finalObject entity){ 8c>xgFWp9
getHibernateTemplate().save(entity); 2%*\XPt)
} 7-0j8$`
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publicvoid update(finalObject entity){ ~z,qr09
getHibernateTemplate().update(entity); SE(c_ sX
} R7KV
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publicvoid delete(finalObject entity){ h
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getHibernateTemplate().delete(entity); ]u:_r)T
} KT17I&:
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publicObject load(finalClass entity, ~Orz<%k.
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finalSerializable id){ LXZI|K[}k
return getHibernateTemplate().load 0g~Cdp
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(entity, id); Z{/GT7 /
} 8n:N#4Dh^
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publicObject get(finalClass entity, 5m;BL+>YE
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finalSerializable id){ 6G}4KGQc
return getHibernateTemplate().get A~^x*#q{4
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(entity, id); 18p4]:L
} ;/kmV~KG
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publicList findAll(finalClass entity){ !Rgj'{
return getHibernateTemplate().find("from &aa3BgxyE
awjAv8tPO!
" + entity.getName()); '&2-{Y [!
} hc|#JS2H@y
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publicList findByNamedQuery(finalString _^`V0>Mh:
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namedQuery){ f0R+Mz8{
return getHibernateTemplate 6urU[t1
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().findByNamedQuery(namedQuery); *xITMi
} d+6q%U
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publicList findByNamedQuery(finalString query, JT~Dr KI_
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finalObject parameter){ UJ(UzKq8
return getHibernateTemplate |n^rI\p%
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().findByNamedQuery(query, parameter); lR9uD9Dr
} I?Z"YR+MQ
u } +?'B)
publicList findByNamedQuery(finalString query, c=QN!n:
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finalObject[] parameters){ Jr= fc*f
return getHibernateTemplate [LUqF?K&
T LF'7ufq
().findByNamedQuery(query, parameters); Le{.B@2-"
} Q04
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publicList find(finalString query){ #{^qBP[
return getHibernateTemplate().find g#Ta03\
yy[ Y=
(query); YU!s;h
} cSNeWJKA6
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publicList find(finalString query, finalObject ledr[)
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parameter){ D;jbZ9
return getHibernateTemplate().find s:(z;cj/
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(query, parameter); _OS,zZ0
} %o{IQ4Lz#
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public PaginationSupport findPageByCriteria "WO0rh`
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(final DetachedCriteria detachedCriteria){ {`T^&bk
return findPageByCriteria H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); -YmIRocx
} td23Z1Elk#
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public PaginationSupport findPageByCriteria X#K;(.},h
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(final DetachedCriteria detachedCriteria, finalint {MTtj4$
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startIndex){ x5Fo?E
return findPageByCriteria zMBGpqdP
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(detachedCriteria, PaginationSupport.PAGESIZE, c&{= aIe w
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startIndex); uJeJ=7,EO
} 53pT{2]zAi
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public PaginationSupport findPageByCriteria x;-D}#
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(final DetachedCriteria detachedCriteria, finalint " vc4QH$
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pageSize, IiE^HgM
finalint startIndex){ $J,$_O6
return(PaginationSupport) moh,a B#
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate C3~~h|:
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(Session session)throws HibernateException { LU`)
Criteria criteria = e"XolM0IM
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detachedCriteria.getExecutableCriteria(session); *M0O&" ~j
int totalCount = rKdsVW
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((Integer) criteria.setProjection(Projections.rowCount ;l `Ufx
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()).uniqueResult()).intValue(); bFlI:R&<
criteria.setProjection Q)qJ6-R|HD
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(null); ITi#p%
List items = OYn5k6
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criteria.setFirstResult(startIndex).setMaxResults 1/qD5 *`Y
w}t}Sh
(pageSize).list(); ?hR0
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PaginationSupport ps = d{@'&?tj
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new PaginationSupport(items, totalCount, pageSize, b`^?nD7
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startIndex); <S6?L[_
return ps; fQg^^ZXe"
} 7.g,&s%q
}, true); SkVah:cF-
} _^zs(
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public List findAllByCriteria(final $AMcU5^b7
K V?+9qa,
DetachedCriteria detachedCriteria){ j]5e$e{
return(List) getHibernateTemplate nmE H/a
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().execute(new HibernateCallback(){ *ezft&{)`
publicObject doInHibernate B4+u/hkbh?
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(Session session)throws HibernateException { I3T;|;P7
Criteria criteria = xS+xUi
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detachedCriteria.getExecutableCriteria(session); a\Gd;C ^`
return criteria.list(); e7&RZ+s#wZ
} 0JR)-*
}, true); 2e3AmR@*
} j>
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public int getCountByCriteria(final ?@`5^7*
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DetachedCriteria detachedCriteria){ VsK8 :[Al
Integer count = (Integer) k+je-%hPj
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getHibernateTemplate().execute(new HibernateCallback(){ %]tW2s"
publicObject doInHibernate k*F9&-rtN
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(Session session)throws HibernateException { I|c?*~7*
Criteria criteria = 0QrRG$<4X
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detachedCriteria.getExecutableCriteria(session); AxTFVot
return o:
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criteria.setProjection(Projections.rowCount ?>vkY^/
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()).uniqueResult(); 6Iz!_
} pI>GusXg
}, true); n: {f\
return count.intValue(); <4 /q5*&
} |q\i, }
} cSG(kFQ
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用户在web层构造查询条件detachedCriteria,和可选的 .i` -t"
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 F4Cq85#
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PaginationSupport的实例ps。 Nr]guC? rE
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ps.getItems()得到已分页好的结果集 B/3xV:Gy
ps.getIndexes()得到分页索引的数组 ,MHF
ps.getTotalCount()得到总结果数 1UB.2}/:
ps.getStartIndex()当前分页索引 UalwK
ps.getNextIndex()下一页索引 Jk{v(W#
ps.getPreviousIndex()上一页索引 G- ]_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 >I&s%4
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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 WBzPSnS2
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一下代码重构了。 5pHv5e
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我把原本我的做法也提供出来供大家讨论吧: 8S[bt@v
wW<u)|>ye
首先,为了实现分页查询,我封装了一个Page类: U2Ky4UFm
java代码: #}tdA(
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/*Created on 2005-4-14*/ /WX&UAG
package org.flyware.util.page; 2IkyC`
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/** V%zo[A
* @author Joa -|=)
* $!\L6;:
*/ sY]pszjT
publicclass Page { y4&x`|tv
F
hyY+{%
/** imply if the page has previous page */ a
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privateboolean hasPrePage; rQpQqBu
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/** imply if the page has next page */
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privateboolean hasNextPage; Vk76cV
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/** the number of every page */ 7p{uRSE4._
privateint everyPage; n#
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/** the total page number */ Jt?`(H
privateint totalPage; mQK3YoC)
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/** the number of current page */ ?]TtUoY=)F
privateint currentPage; =">0\#
b%VZPKA;
/** the begin index of the records by the current !!~r1)zN
#!r>3W&
query */ Ov.oyke4
privateint beginIndex; =#&+w[4?&.
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/** The default constructor */ dw| VH1fS
public Page(){ #210 Yp#
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} 7--E$!9O,
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/** construct the page by everyPage zzT4+wy`
* @param everyPage ykxAm\O
* */ .j"@7#tW
public Page(int everyPage){ *I k/Vu%;
this.everyPage = everyPage; w3ZOCWJS
} ;g<y{o"Q3p
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/** The whole constructor */ \e%%ik,<
public Page(boolean hasPrePage, boolean hasNextPage, RgzzbW
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Hig.` P
int everyPage, int totalPage, F-D$Y?m
int currentPage, int beginIndex){ 5`::#[
this.hasPrePage = hasPrePage; zN\C
this.hasNextPage = hasNextPage; +.xK`_[M
this.everyPage = everyPage; lKS 2OOYC`
this.totalPage = totalPage; 3u,B<
this.currentPage = currentPage; MK!Aq^Jz
this.beginIndex = beginIndex; !d95gq<=>
} 0J;Qpi!u2v
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/** x l=i_
* @return s/P+?8'9
* Returns the beginIndex. d?/>Qqw:#
*/ /2$d'e
publicint getBeginIndex(){ Mh@n>+IR
return beginIndex; Qzv&
} '7.4!I0'
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/** IL"N_ux~w~
* @param beginIndex C)%qs]
* The beginIndex to set. bb-u'"5^]
*/ STPRC&7;
publicvoid setBeginIndex(int beginIndex){ #jPn7
this.beginIndex = beginIndex; *thm)Mn
} ?0lz!Nq'S
| S'mF6Y
/** 4Wa*Pcj
* @return 2{B
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* Returns the currentPage. :kd]n$]
*/ Hv%$6,/ *v
publicint getCurrentPage(){ BW"24JhF"
return currentPage; Uyd' uC
} uhB
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/** p+b$jKWQ
* @param currentPage "ZFH_5<
* The currentPage to set. |n~,{=
*/ sFsf~|
publicvoid setCurrentPage(int currentPage){ W mx3@]<
this.currentPage = currentPage; $ k_6
} R{Cbp=3J
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/** d;{k,rP6
* @return x1Z*R+|>2
* Returns the everyPage. be?Bf^O>
*/ eDvh3Y<D
publicint getEveryPage(){ >=.3Vydi1
return everyPage; js%n]$N
} Ei=rBi
u^W!$OfZpp
/** @|e
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* @param everyPage p8Z;QH*
* The everyPage to set. #qeC)T
*/ =r3g:j/>q
publicvoid setEveryPage(int everyPage){ DgB;6Wl
this.everyPage = everyPage; :39arq
} c:<a"$
YGRb|P-
/** Jm"W+! E
* @return kO$n0y5e
* Returns the hasNextPage. |I{3~+E h
*/ s_e*jM1
publicboolean getHasNextPage(){ mc{W\H
return hasNextPage; [a?bv7Kz
} A;o({9VH`Z
Ge^,hAM'
/** ^66OzT8A
* @param hasNextPage =YD<q:n4
* The hasNextPage to set. N>1d]DrQR
*/ y,w_x,m
publicvoid setHasNextPage(boolean hasNextPage){ PWkSl
this.hasNextPage = hasNextPage; +@*>N;$
} hTmJ
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/** l}&2A*c.
* @return $\bVu2&I
* Returns the hasPrePage. }Z<Sca7
*/ gyhy0
publicboolean getHasPrePage(){ #&1gVkvp
return hasPrePage; afzx?ekdF
} GSd:Plc%
mIqm/5
/** M9m~ck
* @param hasPrePage ;zV<63tW
* The hasPrePage to set. o$V0(1N
*/ #M5d,%?+#[
publicvoid setHasPrePage(boolean hasPrePage){ RzzU+r
this.hasPrePage = hasPrePage; 5(E&jKn&
} Mc!LC
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/** Ih4$MG6QC
* @return Returns the totalPage. 1LAd5X
* 1&<o3)L:
*/ ]cVDXLj$
publicint getTotalPage(){ E> $_
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return totalPage; b?qV~Dgk`
} `AvK=]
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/** V>GJO (9
* @param totalPage )jg*u}u
0
* The totalPage to set. dQ9W40g1
*/ y6x./1Nb}<
publicvoid setTotalPage(int totalPage){ S8v?H|rm
this.totalPage = totalPage; lNtxM"G&
} &K(y%ieIJ
V{w &RJ
} 'J5F+,\Ka
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U^% )BI
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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 P1B=fgT
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个PageUtil,负责对Page对象进行构造: z!18Jh
java代码: \8s:I+[HH
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/*Created on 2005-4-14*/ -.ZP<,?@F
package org.flyware.util.page; z@pa;_
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import org.apache.commons.logging.Log; P8|ANe1
v
import org.apache.commons.logging.LogFactory; `Syfl^9B
u/-EVCHr
y
/** $Bl51VjN
* @author Joa :FtV~^Z
* WBkx!{\z
*/ aNNRw(0/
publicclass PageUtil { !MOsP<2
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privatestaticfinal Log logger = LogFactory.getLog o?t H[
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(PageUtil.class); V45adDiZ
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/** Ip=QtNW3\
* Use the origin page to create a new page _z{9V7n4
* @param page ",Vx.LV
* @param totalRecords "::2]3e
* @return (_>SuQK
*/ JMo r[*
publicstatic Page createPage(Page page, int un -h%-e|
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totalRecords){ = >tkc/aa
return createPage(page.getEveryPage(), /IJy'@B
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page.getCurrentPage(), totalRecords); x9a\~XL>a
} #OM)71kB8
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/** qGEp 6b H
* the basic page utils not including exception a`#lYM%(>
~yw]<{ ?
handler *?HoN;^
* @param everyPage w4\
3*
* @param currentPage PsXCpyY!s
* @param totalRecords oQu>Qr{Zp
* @return page \R]2YY`EP
*/ { AYW
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publicstatic Page createPage(int everyPage, int EA8plQ~GtE
PQSmBTs.
currentPage, int totalRecords){ >c<xy>N
everyPage = getEveryPage(everyPage); K[OOI~"C
currentPage = getCurrentPage(currentPage); Bl8|`R^g
int beginIndex = getBeginIndex(everyPage, #Pf<2S
7g+T
currentPage); w?|qKO
int totalPage = getTotalPage(everyPage, tUc<ExvP,
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totalRecords); 2sk7E'2(
boolean hasNextPage = hasNextPage(currentPage, H{=G\N{
e"eIQI|N
totalPage); 3.BUWMD
boolean hasPrePage = hasPrePage(currentPage); 5 D^#6h 4
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returnnew Page(hasPrePage, hasNextPage, qAH^BrJ
everyPage, totalPage, GU2TQx{V
currentPage, zm5PlG
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beginIndex); q@[F|EF=
} 6?<lS.s
jmaw-Rx
privatestaticint getEveryPage(int everyPage){ :" !Z9l\@
return everyPage == 0 ? 10 : everyPage; Kd+E]$F_OH
} ,iP
YsW]5
W7
Iy _>
privatestaticint getCurrentPage(int currentPage){ uZrp ^
return currentPage == 0 ? 1 : currentPage; o)@nnqa
} r2.w4RMFua
T:{r*zLSN
privatestaticint getBeginIndex(int everyPage, int "D_:`@V(
i^.eX
VV/
currentPage){ E\s1p:%
return(currentPage - 1) * everyPage; |a#ikY _nd
} {._'Q[
Ru*gbv,U
privatestaticint getTotalPage(int everyPage, int W5`p Qdk
(W:@v&p
totalRecords){ 7UW\|r
int totalPage = 0; HOWpTu(
!Ea! "}
if(totalRecords % everyPage == 0) a"U3h[;$y
totalPage = totalRecords / everyPage; 2h51zG#qd
else E:**gvfq
totalPage = totalRecords / everyPage + 1 ; 2 >O [Y1
i]k)wr(
return totalPage; g&2g>]
} O H2IO
p+]S)K GZw
privatestaticboolean hasPrePage(int currentPage){ qX-5/;n
return currentPage == 1 ? false : true; TA*}p=?6?!
} ]YhQQH1>]
vJ'22)n
privatestaticboolean hasNextPage(int currentPage, Lr*PbjQDIY
TCyev[(
int totalPage){ Z!|r>
return currentPage == totalPage || totalPage == %+j/nA1%S
SQf[1}$ .
0 ? false : true; `f~bnL
} \^dse
h?n?3x!(
~\NQkaBkY
} xtv%C
7:vl -ZW
lF/
Xs
BI)C\D3[
?B ,<gen
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。 9;7"S.7AV
!|4]V}JQ
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 :~"myn,
Q}B]b-c+E
做法如下: tUULpx.h
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]m 3cm
`H:`JBe=+[
的信息,和一个结果集List: )JTQZ,f3]
java代码: =L#&`s@)_
tb~E.Lm\
y-.{){uaD
/*Created on 2005-6-13*/ Ir>4- @
package com.adt.bo; sv%E5@
&K'*67h
import java.util.List; P<&bAsje
y$-@|M$GG
import org.flyware.util.page.Page; eJ45:]_%I@
u5ZyOZ;
/** LBD],Ba!
* @author Joa Iv
*/ AzJ;EtR
publicclass Result { T_Tu>wQX
r?[[.zm"7
private Page page; dYD;Z<l
z~`X4Segw
private List content; 8=Oym~
&UnhYG{A
/** +zch e
* The default constructor $k&v
juB.
*/ <v -YMk@
public Result(){ e6_8f*o|s
super(); w`8H=Hf
} B`R@%US
l9|K,YVW
/** )s:kQ~+
* The constructor using fields n;:.UGl9.
* O6?{@l
* @param page 7P(o!%H
* @param content UVlB=
*/ .up[wt gN
public Result(Page page, List content){ S[$9_J f
this.page = page; !\{2s!l~
this.content = content; .^=I&X/P
} fh)eL<I
bK#ZY
/** ;0m J4G
* @return Returns the content. m_Ed[h/I
*/ xa'U_]m
publicList getContent(){ 3YLfh`6
return content; PCaFG;}
} FEu}zt@
u{=h%d/
/** bf.+Ewb(
* @return Returns the page. nkPlfH
*/ p2l@6\m\
public Page getPage(){
W^^0Rh_
return page; =/'>.p3/S
} ".|8 (Y
a"xRc
/** J&'*N:d
* @param content d_$0
* The content to set. -:d{x#
*/ rMJ@oc
public void setContent(List content){ ~.^:?yCA
this.content = content; m=E/um[D
} :kI[Pf!z
%KO8i)n
/** P]^8Enp
* @param page <Tgubv+J
* The page to set. Y9f7~w^s
*/ ,^mEi
publicvoid setPage(Page page){ (T2HUmkQ6
this.page = page; *^]
}
MwQtf(_
} W?E01"p
e^~dx}X
Y'P^]Q=}_#
@+M1M2@Xz
4IW90"uc
2. 编写业务逻辑接口,并实现它(UserManager, l<=k#d
I&15[:b=-
UserManagerImpl) wsrdBxd5
java代码: !X"nN9k
r`FTiPD.C
YSB> WBS-<
/*Created on 2005-7-15*/ C<:wSS^@1
package com.adt.service; D6e?J.
>J;J&]Olf
import net.sf.hibernate.HibernateException; +7WpJ;C4
8%4v6No&*
import org.flyware.util.page.Page; GfP'
D?Ol)aj?
import com.adt.bo.Result; &~.|9P/45
;A"i.:ZT
/** ^o Ds*F
* @author Joa Bf^K?:r"V
*/ mg70%=qM0f
publicinterface UserManager { 2|exY>`w
.u7grC C
public Result listUser(Page page)throws 2HE<WI^#h
m#Z9wf] F
HibernateException; "\9beK:l
%y>*9$<pXe
} >3 p8o@:
%|/\Qu
HWou&<EK
\mb@-kM)
2"
v{
java代码: 2WKIO|'
NV}fcZ
.gRb'
/*Created on 2005-7-15*/ A#pH$s
package com.adt.service.impl; I)%bOK]
}{J>kgr6
import java.util.List; i[33u p
[ryII hQ
import net.sf.hibernate.HibernateException; IA=\c
z:Ru`
import org.flyware.util.page.Page; f0g_Gn $
import org.flyware.util.page.PageUtil; Y.52`s6F
/^~)iTwH
import com.adt.bo.Result; [8DPZU@
import com.adt.dao.UserDAO; LsMq&a-j2
import com.adt.exception.ObjectNotFoundException; bWCtRli}
import com.adt.service.UserManager; rP(;^8l"
X"f]
/** .)t*!$5=N
* @author Joa ~-yq,x
*/ b9Eb"
publicclass UserManagerImpl implements UserManager { l~1l~Gx_&n
7/=r-
private UserDAO userDAO; \<}e?Yx%
j->5%y
/** gazX2P[D
* @param userDAO The userDAO to set. /I`-
*/ k_OzkEM9!
publicvoid setUserDAO(UserDAO userDAO){ `- 9p)@'8k
this.userDAO = userDAO; (f"LD8MJ/
} H7 {kl
}mk z_P(Z
/* (non-Javadoc) (
~>-6Nb 5
* @see com.adt.service.UserManager#listUser /dR:\ffz2
a8y*Jz-E
(org.flyware.util.page.Page) i Hcy,PBD
*/ IV`+B<3
public Result listUser(Page page)throws )\izL]=!t
eN TKX
HibernateException, ObjectNotFoundException { {I$zmVG
int totalRecords = userDAO.getUserCount(); ,G$<J0R1
if(totalRecords == 0) %x^ U3"7
throw new ObjectNotFoundException *M~BN}.
B1U7z1<
("userNotExist"); sdQ"[`~2R
page = PageUtil.createPage(page, totalRecords); ph7]*W-
List users = userDAO.getUserByPage(page); U]E~7C
returnnew Result(page, users); vri<R8
} Q\le3KB
&X}i%etp^2
} Lnltt86
}K 2fwE
F{m?:A
7t%
|s!~
s%l^zA(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 cD<5~ `l
a7fn{VU8
询,接下来编写UserDAO的代码: H7Ee0T(`
3. UserDAO 和 UserDAOImpl: 6oR5q 4
java代码: E^Z?X2Z
0SDyE
yt`K^07@
/*Created on 2005-7-15*/ " ,45p@
package com.adt.dao; ]6?6 k4@
x?G"58
import java.util.List; Cl!qdh6
_Qf310oONS
import org.flyware.util.page.Page; Uj)`(}r
'iEu1! t\0
import net.sf.hibernate.HibernateException; ,D{D
QJ(B
PCiwQ4~
/** J@(69&
* @author Joa 2?(dS
*/ zHQSx7Ow 5
publicinterface UserDAO extends BaseDAO { +nQp_a1{9%
2fMKS
publicList getUserByName(String name)throws 39Tlt~Psz
p']oy;t
HibernateException; c[4I> "w
:sJQ r._L
publicint getUserCount()throws HibernateException; V\r2=ok@y
Gxh1wqLR
publicList getUserByPage(Page page)throws .]K{8[:hq
N9BfjT}
HibernateException; <2fgao&-n
l[b`4
} /n8\^4{fP{
*f3?0w
/zIUYY
;a~
e
t'e5!Ma
java代码: DDp\*6y3l
t,308Z
zIbrw9G
/*Created on 2005-7-15*/ 6[&x7"
package com.adt.dao.impl; =]W[{@P
f2Z(hYH~
import java.util.List; 9%^O-8!
AkVgFQg"
n
import org.flyware.util.page.Page; _'Hw`0}s
.CBb%onx
import net.sf.hibernate.HibernateException; s73' h
import net.sf.hibernate.Query; em?Q4t
irKM?#h
import com.adt.dao.UserDAO; e3]v
*<bj
RZqou|ki
/** 3?bTs =
* @author Joa v8
pOA<s
*/ K4Hu0
public class UserDAOImpl extends BaseDAOHibernateImpl 9}aEV 0 V|
)H[Pz.'ah0
implements UserDAO { dc,qQM
D7v_<
/* (non-Javadoc) Mk!bmFZOZ
* @see com.adt.dao.UserDAO#getUserByName ygYy [IZ
-qdt$jIM
(java.lang.String) ,d$D0w
*/ j. mla
publicList getUserByName(String name)throws q:u,)6
Tx|y!uHh
HibernateException { V$3`y=8
String querySentence = "FROM user in class W?D-&X^ny
QfRo`l/V9
com.adt.po.User WHERE user.name=:name"; )_SpY\J
Query query = getSession().createQuery /^=8?wK
lwm
9gka
(querySentence); >1RL5_US
query.setParameter("name", name); b!`{fwV
return query.list(); /n1L},67h
} O9_SVXWVw
2&XNT-Qm
/* (non-Javadoc) -.l.@
* @see com.adt.dao.UserDAO#getUserCount() z8cefD9F
*/ |G/WS0
publicint getUserCount()throws HibernateException { jGe%'AN\
int count = 0; /cZTj!M
String querySentence = "SELECT count(*) FROM $0|`h)&
bL/DjsZ@
user in class com.adt.po.User"; USZBk0$
Query query = getSession().createQuery H:cAORLB
UHR%0ae
(querySentence); P~s u]+
count = ((Integer)query.iterate().next _fS4a134R
$N\k*=
()).intValue(); 2WC$r8E
return count; GI6]Ecc
} Ako]34Rl,
KkCsQ~po
/* (non-Javadoc) 3%)@c P:?
* @see com.adt.dao.UserDAO#getUserByPage (C0Wty
Z{x)v5yh2V
(org.flyware.util.page.Page) m"!Q5[
*/ c2-oFLNP=
publicList getUserByPage(Page page)throws Y=t?"E
IZs&7
HibernateException { J vq)%t8q>
String querySentence = "FROM user in class q7<=1r+
JJ9R,
8n6
com.adt.po.User"; opTH6a
Query query = getSession().createQuery WjOP2CVv|
$$i
Gs6az
(querySentence); #n]K$k>
query.setFirstResult(page.getBeginIndex()) oxL)Jx\c9A
.setMaxResults(page.getEveryPage()); [}yPy))A
return query.list(); }46Zfg\T6n
} U9jdb9 |
{.ypZ8JU
} 5+yy:#J]
'I$kDM mwh
\>x1#Vr>#V
$gZiW 8
=\G`g#
至此,一个完整的分页程序完成。前台的只需要调用 ~RLWr.pK
@0(%ayi2Y
userManager.listUser(page)即可得到一个Page对象和结果集对象 y?U@F/^}N
ae" o|Q
的综合体,而传入的参数page对象则可以由前台传入,如果用 A]ZQ?-L/
n|Ts:>`V
webwork,甚至可以直接在配置文件中指定。 }QBL{\E!
Xk\IO0GF
下面给出一个webwork调用示例: uh`5:V
java代码: Swh\^/B8
E\TWPV'/
q3C
/*Created on 2005-6-17*/ 4U~'Oa@p
package com.adt.action.user; <KfR)7I$0a
9WI5\`*"
import java.util.List; X ]W)D
S
hV:++g
import org.apache.commons.logging.Log; "!CVm{7[
import org.apache.commons.logging.LogFactory; K+"3He
import org.flyware.util.page.Page; ;A4j_8\[
:zY;eJK m
import com.adt.bo.Result; ;M~9Yr=1
import com.adt.service.UserService; Z_fwvcZ?05
import com.opensymphony.xwork.Action; P^!g0K
,:2Z6~z{
/** |?nYs>K
* @author Joa $@O?
*/ eK5~YM:o
publicclass ListUser implementsAction{ 4>OS2b`.;
/:ZwGyT;
privatestaticfinal Log logger = LogFactory.getLog (:F]@vT
+r7hc;+G
(ListUser.class); ]=9 d'WL
KDP"z
private UserService userService; w}#3 pU<<
zliMG=6
private Page page; )Ly~\*
u80C>sQ
privateList users; &*Xrh7K2e
d2d8,Vg
/* &n6L;y-
* (non-Javadoc) E0/>E
* #-PMREgO
* @see com.opensymphony.xwork.Action#execute() |?ZU8I^vW
*/ ycSGv4
)
publicString execute()throwsException{ Ijap%l1I
Result result = userService.listUser(page); fj/L)i
page = result.getPage(); @3$ I
users = result.getContent(); JZ+6)R
return SUCCESS; Vr Lp5?Bh
} zA}JVB
v*0J6<
/** m5&Ht (I%n
* @return Returns the page. X)6 G :cD
*/ l0;u$
public Page getPage(){ ]uF7HX7F
return page; E_I-.o|
} pJs`/
vq.o;q /
/** Ook\CK*nKe
* @return Returns the users. YtKT3u:x
*/ pUS: HJk|
publicList getUsers(){ 4`mf^Kf
return users; Ph%ylS/T{
} {[`(o
0@(
(+;D~iN` k
/** [[]yQ
"
* @param page bCr
W'}:de
* The page to set. )P? F ni}
*/ QV.>Cy
publicvoid setPage(Page page){ $y,KDR7^
this.page = page; QH4m7M@ni
} #pgD-0_
.P7q)lj36h
/** '
`c \Dq
* @param users f3qR7%X?
* The users to set. Er|&4-9
*/ &bfM`h'
publicvoid setUsers(List users){ qo7<g*kf~
this.users = users; Mpyza%zj
} !/tV}.*
g!'
x5#]n
/** y9]7LETv\M
* @param userService aMGh$\Pg
* The userService to set. ky]^N)
*/ SP<Sv8Okj
publicvoid setUserService(UserService userService){ V6](_w!
this.userService = userService; \)wVO*9*0
} v;5-1
} 0tL5t7/Gr
d}fd^x/
Sz<:WY/(x
Gey-8
V`LE 'E
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, A^6z.MdYZ
wBg?-ji3<
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 {d'B._#i
?lgE9I]
么只需要: r>|S4O
java代码: X_nbNql
Ye4
&4t
Sin)]zG~0
<?xml version="1.0"?> xi.?@Lff
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork dc4XX5Z
H1%o)'Kut4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- l{.PyU5)
*0@Z+'M?
1.0.dtd"> jg'"?KSU~
D4(73
<xwork> frm[<-~ w0
bv(+$YR
<package name="user" extends="webwork- 0%,W5w
YfZ5Q}*1O+
interceptors"> ## vP(M$
.pe.K3G&
<!-- The default interceptor stack name W{!5}Sh
J Q*~le*
--> !Sy9v
<default-interceptor-ref g\/|7:yB]
CdCY#$Z
name="myDefaultWebStack"/> 1I'}Uh*
GHLnwym
<action name="listUser" K"g{P
i !sVQ(:
class="com.adt.action.user.ListUser"> >7X5/z
<param 4IB`7QJq
9;vES^
name="page.everyPage">10</param> P8=J0&5
<result y]obO|AH
?P9VdS1-
name="success">/user/user_list.jsp</result> r/0#D+A
</action> 7^Us
q[vO
mes
</package> S/y(1.wh
RT'5i$q[
</xwork> Zn.S65J*u
E=S_1
sA: /!9
i=>`=. ~
tRc3<>
J32{#\By
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 `WC4:8
bT9:9LP
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。 rO#$SW$YW
^mI`P}5Y
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 v6aMYmenBH
X=6L-^o)
hHcevSr
rk,64(
C'l\4ij)7
我写的一个用于分页的类,用了泛型了,hoho j+/EG^*/
&.z-itiV
java代码: *"F*6+}w"
h<?I?ZR0$
"FGgem%9
package com.intokr.util; _h=h43'3
s:,fXg25J
import java.util.List; GO][`zZJ]
XM?c*,=fu
/** p((. (fx
* 用于分页的类<br> P??pWzb6HH
* 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!&4o
* n
Zx^ej\
* @version 0.01 T?u*ey~Tv
* @author cheng /Z#AHfKF
*/ 93w$ck},?G
public class Paginator<E> { e*Nm[*@UW
privateint count = 0; // 总记录数 MfLus40;n
privateint p = 1; // 页编号 l{ fL~O
privateint num = 20; // 每页的记录数 SFsT^f<
privateList<E> results = null; // 结果 sZqi)lo-s
+&_n[;
/** _J"J[$
* 结果总数 biffBC:q
*/ ahM?;p
publicint getCount(){ c-@EHv
return count; pAN$c"
} I]m&h!
/dX,]OFm
publicvoid setCount(int count){ Ja\B%f
this.count = count; .fhfO @
} +`m0i1uI3
u |$GOSD
/** !a'{gw
* 本结果所在的页码,从1开始 \4*i;a.kU
* ke +\Z>BWN
* @return Returns the pageNo. ]Qx-f*
D6
*/ G
jrN1+9=
publicint getP(){ ?f:\&+.&
return p; j=>WWlZ
} &.0 wPyw
6ESS>I"su
/** )OGO
wStz
* if(p<=0) p=1 SnO,-Rg
* Qej<(:J5
* @param p OW> >6zM
*/ iqXsDgkr
publicvoid setP(int p){ tjm@+xs
if(p <= 0) FW<YN;
p = 1;
DshRH>7s8
this.p = p; E@="n<uS
} FEA/}*2F
<@@@Pl!~
/** +w@/$datI
* 每页记录数量 .M\0+,%/
*/ *OKve
publicint getNum(){ =&U7:u
return num; N9f;X{
} _~ 7cn
2)
A$bx
/** Bk1gE((
* if(num<1) num=1 :w c.V
*/ ?DJ,YY9P
publicvoid setNum(int num){ K:sC6|wG
if(num < 1) Yr+ghl/ V
num = 1; zd[cp@
this.num = num; RFm9dHI27
} DfP
vi1
.J|"bs9
/** ps?B;P
* 获得总页数 ^S`c-N
*/ P}Ul e|&LK
publicint getPageNum(){ 5 %aT
return(count - 1) / num + 1; $;+`sVG
} o//PlG~
T k>N4yq
/** $yg}HS7HC
* 获得本页的开始编号,为 (p-1)*num+1 !7[Rhk7bW
*/ )c<5:c
publicint getStart(){ ;;- I<TL
return(p - 1) * num + 1; 0bk094
} !ly]{DTmm
LaiUf_W #X
/** }vdhk0
* @return Returns the results. =u`^QE
*/ +EgQj*F*
publicList<E> getResults(){ =zW.~(c{
return results; PfVjfrI[
} D(<20b,
+Gvf5+ 5VR
public void setResults(List<E> results){ kQm\;[R
this.results = results; TXQY&7
} Kth^WHL
x:Kca3p v_
public String toString(){ enT.9|vm/
StringBuilder buff = new StringBuilder EGyQhZ mO
dPRGL
hWF
(); e[8p /hId
buff.append("{"); "^ cn9AG{
buff.append("count:").append(count); j^~WAWbFh
buff.append(",p:").append(p); %@jv\J
buff.append(",nump:").append(num); Iih~rWJ
buff.append(",results:").append ~8EG0F;t
fXYg %
(results); "I]% aK0
buff.append("}"); yeNC-U<
return buff.toString(); %k3a34P@
} qN_jsJ
T=2 91)@
} iwfv t^
b-+iL
`+QrgtcEy4