Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~jDG&L
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 8IX,q
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 JXKqQxZ[X
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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 ~T_4M
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。 uGxh}'&
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分页支持类: */ ~_ 3
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java代码: NQx`u"=
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package com.javaeye.common.util; uFzvb0O`O
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import java.util.List; LR5X=&k
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publicclass PaginationSupport { l".LtUf-
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publicfinalstaticint PAGESIZE = 30; |H LU5=Y
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privateint pageSize = PAGESIZE; >*hY1@N1
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privateList items; NR*s7>
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privateint totalCount; EPE9HvN
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privateint[] indexes = newint[0]; 1m52vQSo3l
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privateint startIndex = 0; bP4<q?FKcN
=Qa*-*
public PaginationSupport(List items, int h]6"~ m
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totalCount){ U',9t
setPageSize(PAGESIZE); /n9yv
setTotalCount(totalCount); =sR]/XSK
setItems(items); }3"FQ/6C
setStartIndex(0); "o=*f/M
} HH\6gs]u
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public PaginationSupport(List items, int [%8t~zg
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totalCount, int startIndex){ eX;Tufe*(Q
setPageSize(PAGESIZE); qB`-[A9HPe
setTotalCount(totalCount); &m>yY{be
setItems(items); y?t2@f]!XK
setStartIndex(startIndex); RY>BP[h
} #~
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public PaginationSupport(List items, int DP(JsZ}
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totalCount, int pageSize, int startIndex){ xHA6
setPageSize(pageSize); ;W/K7}
setTotalCount(totalCount); 7 +RsZu
setItems(items); -|?I'~[#(
setStartIndex(startIndex); 4oY<O
} #s'UA!)
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publicList getItems(){ JAjXhk<=
return items; bJ[{[|yEd
} /~,|zz
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publicvoid setItems(List items){ ( 1 L9K;
this.items = items; M@G <I]\
} Rmq8lU
q`l&G%
publicint getPageSize(){ $R\D[`y|
return pageSize; ileqI/40f
} ;"*\R5a
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publicvoid setPageSize(int pageSize){ &a'H vQV
this.pageSize = pageSize; 9q?\F
} sHk,#EsKH
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publicint getTotalCount(){ WBo|0(#
return totalCount; .>5KwEK~
} 4K_ fN
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publicvoid setTotalCount(int totalCount){ tD G[}j
if(totalCount > 0){ i2a""zac
this.totalCount = totalCount; D{Zjo)&tF'
int count = totalCount / .|[5*-
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pageSize;
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if(totalCount % pageSize > 0) x*8lz\w
count++; B74L/h
indexes = newint[count]; c$cb2V7,
for(int i = 0; i < count; i++){ c.-/e u^|
indexes = pageSize * SJYy,F],V"
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i; `N+A8
} bN Ub
}else{ So?ScX\lG
this.totalCount = 0; FME&vUh/
} u7rA8u|TO
} eXHk6[%[
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publicint[] getIndexes(){ (J c} K
return indexes; ZT
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} MwoU>+XB
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publicvoid setIndexes(int[] indexes){ =%p%+F@RlW
this.indexes = indexes; "pb$[*_@$
} YbMeSU/sX
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publicint getStartIndex(){ 8\z5* IPGs
return startIndex; K$S:V=y%r7
} 8Ol#-2>k$
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publicvoid setStartIndex(int startIndex){ Pj4WWK X
if(totalCount <= 0) -&PiD
this.startIndex = 0; *z2G(Uac
elseif(startIndex >= totalCount) bCM&Fe0GM
this.startIndex = indexes 8hx4s(1!
0!WF,)/T7i
[indexes.length - 1]; h$#QRH
elseif(startIndex < 0) K`=O!;
this.startIndex = 0; VDCG
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else{ '=|2, H]
this.startIndex = indexes f0uzoeL<%
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[startIndex / pageSize]; {-(}p+;z
} ZI'MfkEZ*
} A]fN~PR
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publicint getNextIndex(){ Yx- 2ux
int nextIndex = getStartIndex() + 0 mJvoz\j8
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pageSize; !.\EU*)1
if(nextIndex >= totalCount) C2WWS(zn
return getStartIndex(); $T\W'WR>
else [@!.( Hp
return nextIndex; 8|>$M
} :r?gD2q
_ >)+
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publicint getPreviousIndex(){ P\;L#2n
int previousIndex = getStartIndex() - L5%t.7B
j2V"w&>b}
pageSize; gy|L!_1Z8
if(previousIndex < 0) QXXB>gOY5
return0; s}MD;V&0
else 1Sk=;Bic
return previousIndex; l(-We.:(
} TO&ohATp
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} nz72w_
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抽象业务类 =oZHN,
java代码: rToZN!q\S
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/** N=1zhI:VaQ
* Created on 2005-7-12 AJk0jh\.j%
*/ P5u
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package com.javaeye.common.business; dGxk
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import java.io.Serializable; J~=bW\^I
import java.util.List; R+'$V$g\X
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import org.hibernate.Criteria; ET]PF ,`
import org.hibernate.HibernateException; 6OBe^/ZRt
import org.hibernate.Session; d~i WV6Va
import org.hibernate.criterion.DetachedCriteria; ?gknJ:
import org.hibernate.criterion.Projections; ?xftr (
import EV1x"}D A_
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org.springframework.orm.hibernate3.HibernateCallback; /RVy?)hVT#
import \rXmWzl{
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org.springframework.orm.hibernate3.support.HibernateDaoS @J`o
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upport; .YV{w L@cB
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import com.javaeye.common.util.PaginationSupport; #BB,6E
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public abstract class AbstractManager extends :O`7kZ]=n
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HibernateDaoSupport { OT1
@ |bN[X L
privateboolean cacheQueries = false; 4(
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/ z<7gd~oU
privateString queryCacheRegion; ^$8@B]*
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publicvoid setCacheQueries(boolean
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cacheQueries){ U
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this.cacheQueries = cacheQueries; `pMI@"m
} h |Ofi
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publicvoid setQueryCacheRegion(String Rm@#GP`
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queryCacheRegion){ SM57bN
this.queryCacheRegion = }ufzlHD
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queryCacheRegion; gN,O)@N'd3
} &cZQ,o
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publicvoid save(finalObject entity){ QO1pwrX<
getHibernateTemplate().save(entity); dTV4 Q`Z
} F$L2bgQR?'
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v
publicvoid persist(finalObject entity){ I5nxY)v
getHibernateTemplate().save(entity); OyI?P_0u
} ` ,lm:x+(0
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publicvoid update(finalObject entity){ KCBA`N8
getHibernateTemplate().update(entity); L/ L#[
} z7vc|Z|
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publicvoid delete(finalObject entity){ /
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getHibernateTemplate().delete(entity); AnF"+<
} Sb2hM~
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publicObject load(finalClass entity, XmZs4~\K$G
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finalSerializable id){ a&^HvXO(>(
return getHibernateTemplate().load ro& /
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(entity, id); [Rj_p&'
} ^sF/-/ {?U
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publicObject get(finalClass entity, 0W_olnZ
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finalSerializable id){ WGmXq.
return getHibernateTemplate().get (vR9vOpJ
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(entity, id); ZVelKI8>
} ABx< Ep6
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publicList findAll(finalClass entity){ c
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return getHibernateTemplate().find("from 8+*
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" + entity.getName()); c-jE1y<
} <E2nM,
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publicList findByNamedQuery(finalString |o@xWs@m
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namedQuery){ ,`pUz[wl
return getHibernateTemplate T`zUgZ]
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().findByNamedQuery(namedQuery); mm
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} \CU-a`n
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publicList findByNamedQuery(finalString query, >g>L>{
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finalObject parameter){ ;i'mma_!
return getHibernateTemplate
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().findByNamedQuery(query, parameter); ^)nIf)9}7
} *'-[J 2
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publicList findByNamedQuery(finalString query, kC_Kb&Q0
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finalObject[] parameters){ wbpz,
return getHibernateTemplate W>_K+:t
Hhzi(<e^
().findByNamedQuery(query, parameters); ixvF`S9
} W"
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publicList find(finalString query){ [mcER4]}
return getHibernateTemplate().find ;RW0Dn)Q
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(query); qNuBK6E#4
} I.6
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publicList find(finalString query, finalObject Q)/oU\
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parameter){ R:5uZAx
return getHibernateTemplate().find 1F'x$~ZI
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(query, parameter); gq7l>vT.
} HhZ>/5'(
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public PaginationSupport findPageByCriteria (|2:^T+
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(final DetachedCriteria detachedCriteria){ ^Q#g-"b
return findPageByCriteria B9:
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); uj~(r=%
} ~]Weyb[N
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public PaginationSupport findPageByCriteria I_s* pT
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(final DetachedCriteria detachedCriteria, finalint Krd0Gc~\|
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startIndex){ ;S?ei>Q
return findPageByCriteria 1>=]lMW
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(detachedCriteria, PaginationSupport.PAGESIZE, K2qKkV@
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startIndex); n`X}&(O
} S*NeS#!v
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public PaginationSupport findPageByCriteria {O!B8a
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(final DetachedCriteria detachedCriteria, finalint Tg@:mw5
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pageSize, cz41<SFL
finalint startIndex){ MMy\u) 4
return(PaginationSupport) -KL5sK
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getHibernateTemplate().execute(new HibernateCallback(){ #G]g
publicObject doInHibernate O%1uBc
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(Session session)throws HibernateException { V`4/oM`
Criteria criteria = Gm[XnUR7V
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detachedCriteria.getExecutableCriteria(session); 'j\~> a3\
int totalCount = blKF78
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((Integer) criteria.setProjection(Projections.rowCount =eQ'^3a
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()).uniqueResult()).intValue(); (&1565
criteria.setProjection 6(/*E=bOKV
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(null); )@],0yL
List items = f<;eNN
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criteria.setFirstResult(startIndex).setMaxResults x3l~k Z(
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(pageSize).list(); KjK-#F,@
PaginationSupport ps = iBk1QRdn
#'5{
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new PaginationSupport(items, totalCount, pageSize, &3|l4R\
7 &iav2q
startIndex); J|u_45<
return ps; 1oI2
} Q"QZ^!zRl
}, true); 98*C/=^TH{
} 6lm<>#_
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public List findAllByCriteria(final I`nC\%g
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DetachedCriteria detachedCriteria){ r8>Qs RnU%
return(List) getHibernateTemplate fuT Bh6w&
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().execute(new HibernateCallback(){ zym6b@+jN
publicObject doInHibernate g'NR\<6A
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(Session session)throws HibernateException { MxqIB(5k
Criteria criteria = y9~:[ jB
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detachedCriteria.getExecutableCriteria(session); 0.&-1pw
return criteria.list(); c#Qlr{ES
} A"6&
}, true); m$VCCDv
} GO3KKuQ=
qS?^(Vt|R
public int getCountByCriteria(final !
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DetachedCriteria detachedCriteria){ V6&6I
Integer count = (Integer) J;N\q
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getHibernateTemplate().execute(new HibernateCallback(){ F{E`MK~f_
publicObject doInHibernate j9R+;u/!
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(Session session)throws HibernateException { Bo;{ QoB
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); ^;[^L=}8$
return |Es,$
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criteria.setProjection(Projections.rowCount =
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()).uniqueResult(); !$p E=~1C
} %zN~%mJG
}, true); ^fP5@T*f
return count.intValue(); ir~4\G!
} p:
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} l4YTR4D
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用户在web层构造查询条件detachedCriteria,和可选的 q!WiX|P
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 jP.dQj^j&
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PaginationSupport的实例ps。 _opB,,G
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ps.getItems()得到已分页好的结果集 #Eqx Eo;
ps.getIndexes()得到分页索引的数组 6M[OEI5
ps.getTotalCount()得到总结果数 Bqw/\Lxwlf
ps.getStartIndex()当前分页索引 s14ot80)
ps.getNextIndex()下一页索引 WH<\f|xR
ps.getPreviousIndex()上一页索引 f%yNq6l
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \*Z:w3;r
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 \"P$*y4Le
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一下代码重构了。 ]?_V+F
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我把原本我的做法也提供出来供大家讨论吧: ->W rBO
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首先,为了实现分页查询,我封装了一个Page类: A~;+P
java代码: 2>)::9e4
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/*Created on 2005-4-14*/ {( Ba
package org.flyware.util.page; e!w#{</8Q
i<!1s%i}
/** T/tC X[}
* @author Joa R#Z
m[S
* 6%&DJBU!
*/ J!H)[~2/
publicclass Page { )Ut9k
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/** imply if the page has previous page */ >[<f\BN|
privateboolean hasPrePage; o`nJJ:Cxq-
]3
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/** imply if the page has next page */ X]s="^
privateboolean hasNextPage; -ug-rdXV
#66u<FaG
/** the number of every page */ nMOXy\&mI
privateint everyPage; !3\(
d{
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/** the total page number */ ~I@ %ysR
privateint totalPage; ~sTn?~
ootkf=
/** the number of current page */ 1$ENNq#0
privateint currentPage; 5KW
n >n
6>[J^k%~w)
/** the begin index of the records by the current CIQ9dx7>
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query */ v %S$5
privateint beginIndex; %V92q0XW
x) R4_3
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/** The default constructor */ Zig3WiD&
public Page(){ +XAM2uN5_.
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} RA}Y$ }^#'
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/** construct the page by everyPage Lt{&v^y
* @param everyPage uf`/-jY
* */ wpOM~!9R
public Page(int everyPage){ @"afEMd
this.everyPage = everyPage; \o5/, C
} *a`_,Q{x
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/** The whole constructor */ wdRk+
public Page(boolean hasPrePage, boolean hasNextPage, l?KP/0`
$Q`\-
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int everyPage, int totalPage, >|hqt8lY
int currentPage, int beginIndex){ Agwl2AM5k
this.hasPrePage = hasPrePage; Pk^V6-
this.hasNextPage = hasNextPage; C+0BV~7J<<
this.everyPage = everyPage; c
this.totalPage = totalPage; >ajcfG.k(
this.currentPage = currentPage; D"P<;@ef
this.beginIndex = beginIndex; o'ZW
} :-j/Y'H_
/Tp>aW%}"
/**
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* @return N._^\FRyn
* Returns the beginIndex. >n5Kz]]%
*/ l'?(4N
publicint getBeginIndex(){ ,1i l&
return beginIndex; )Hqn
} P]4@|u;=6[
(!T\[6
/** fKa]F`p_h
* @param beginIndex VKy3tW/_&
* The beginIndex to set. SKVQ !^o
*/ cB2~W%H
publicvoid setBeginIndex(int beginIndex){ ^F-AZP
/5F
this.beginIndex = beginIndex; <#lNi.?.
} 6^TWY[z2%
dbfI!4
/** Cp#}x1{
* @return PBAQ
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* Returns the currentPage. 'L2[^iF9
*/ Jy0(g T
publicint getCurrentPage(){ ?IR+OCAA
return currentPage; LHq*E`
} t=n@<1d
OJs
s
/** sl*&.F,v=
* @param currentPage ~\Udl
* The currentPage to set. df9$k0Fx
*/ p:Zhg{sF
publicvoid setCurrentPage(int currentPage){ _x<7^^VT
this.currentPage = currentPage; 0fx.n
} kQ .3J.Q5
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/** =]-D_$S~
* @return uD:tT~
* Returns the everyPage. )"s(;kU!
*/ 0;" >.
publicint getEveryPage(){ O_Z
return everyPage; $WbfRyXi7'
} j8?rMD~
l8d }g
/** YF13&E2`\
* @param everyPage CjU?3Ag
* The everyPage to set. oTf^-29d
*/ |]OI)w*
publicvoid setEveryPage(int everyPage){ ,h'omU7
this.everyPage = everyPage; vVH*\&H\T
} ^ ]SU (kY
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/** x-SYfvYY
* @return Xl/2-'4
* Returns the hasNextPage. ^%/d]Zwb
*/ z5t"o !
publicboolean getHasNextPage(){ Wp//SV
return hasNextPage; TL([hR _
} L_fiE3G|>
UvVq# <-
/** rq^VOK|L
* @param hasNextPage _Zbgmasb
* The hasNextPage to set. ?^
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*/ V Rz9;=m
publicvoid setHasNextPage(boolean hasNextPage){ *vu
this.hasNextPage = hasNextPage; ~tqDh(
} 'h;x>r
t+n+_X
/** <_-8)abK
* @return >Q|S#(c
* Returns the hasPrePage. =%9j8wHX
*/ 0/zgjT|fe
publicboolean getHasPrePage(){ m"mU:-jk`
return hasPrePage; O-]^_LV`
} usI$
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/** KgEfhO$W
* @param hasPrePage 4 UnN~
* The hasPrePage to set. ehQ~+x
*/ @'FO M
publicvoid setHasPrePage(boolean hasPrePage){ /7Ft1f
this.hasPrePage = hasPrePage; r r(UE
} JAI ;7
q%k _C0
/** _eMY?
* @return Returns the totalPage. 9d&}CZr
* j'|`:^
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*/ rfhvd wwD
publicint getTotalPage(){ };]f 3
return totalPage; %ysfFE
} A@JZK+WB}
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/** ^|=3sJ4[U
* @param totalPage 3Uni{Z]Q)
* The totalPage to set. fnudu0k
*/ |%5nV=&\
publicvoid setTotalPage(int totalPage){ %1e{"_$O9
this.totalPage = totalPage; :faB7wduW;
} -LEpT$v|
5gY9D!;:0D
} <^wqN!/
p`{ | [<
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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 Y(P<9m:
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个PageUtil,负责对Page对象进行构造: #BX^"J{~
java代码: $nW^Gqwj]1
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/*Created on 2005-4-14*/ ~QE- $;
package org.flyware.util.page; :*s+X$x,<
kK$*,]iCp
import org.apache.commons.logging.Log; y,=TB[d#
import org.apache.commons.logging.LogFactory; *p7_rY
\x+ "1
/** ajALca4
* @author Joa {A MoE+U
* M]M(E) *5
*/ wT-@v,$
publicclass PageUtil { rgXD>yu(
K^+}__;]
privatestaticfinal Log logger = LogFactory.getLog q.NvwJ
};@J)}
(PageUtil.class); Z;nUS,?om
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/** 2K$#U|Qi
* Use the origin page to create a new page hZNAI
* @param page UqZ#mK i
* @param totalRecords MuQ'L=i J
* @return Yq0=4#_
*/ K44j-Ypb
publicstatic Page createPage(Page page, int c %.vI
\h 1 T/_4
totalRecords){ lT~A~O
return createPage(page.getEveryPage(), ;OfZEy>7
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page.getCurrentPage(), totalRecords); 088"7 s
} u3@v
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/** qI#ow_lL#
* the basic page utils not including exception uV+.(sjH
%t<ba[9F
handler x$Tf IFy
* @param everyPage =
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* @param currentPage MJ0UZxnl
* @param totalRecords (YH/#n1"{
* @return page (GI]Uyn
*/
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publicstatic Page createPage(int everyPage, int gtV*`g
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currentPage, int totalRecords){ rE&+fSBD
everyPage = getEveryPage(everyPage); >*cg
K}!@
currentPage = getCurrentPage(currentPage); =Frbhh57
int beginIndex = getBeginIndex(everyPage, `Aa*}1
6%RN-
currentPage); ^NPbD<~Lb
int totalPage = getTotalPage(everyPage, H.8Vm[W
58H%#3Fy
totalRecords); u }~%9Pi
boolean hasNextPage = hasNextPage(currentPage, +qzCy/_gd
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totalPage); zS+_6s
boolean hasPrePage = hasPrePage(currentPage); R x.]m0
{f<\`
returnnew Page(hasPrePage, hasNextPage, K JX@?1"
everyPage, totalPage, e<[0H 8
currentPage, OGqsQ
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beginIndex); ,,KGcDBj
} Oe[qfsdW
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privatestaticint getEveryPage(int everyPage){ ~ok i s
return everyPage == 0 ? 10 : everyPage; {#'M3z=
} 'fkaeFzOl
K0Zq)<
privatestaticint getCurrentPage(int currentPage){ Jf{
M[ z
return currentPage == 0 ? 1 : currentPage; @*rED6zH
} b[_${in:
5};$>47m
privatestaticint getBeginIndex(int everyPage, int .A2u7*h&
\<R.F
currentPage){
#RA3 T[A
return(currentPage - 1) * everyPage; qTl/bFD
} U\\nSU
}lzN)e
privatestaticint getTotalPage(int everyPage, int p>@S61
&
[
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totalRecords){ U
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int totalPage = 0; mC}!;`$8p
>7^+ag~&
if(totalRecords % everyPage == 0) r!7e:p JLO
totalPage = totalRecords / everyPage; /NDuAjp[@
else [Ifhh2
totalPage = totalRecords / everyPage + 1 ; 8xEOR!\!`k
;y{VdT
return totalPage; :9Vd=M6,
} +e6c4Tw/
2!4.L&Ki
privatestaticboolean hasPrePage(int currentPage){ '#b7Z?83C
return currentPage == 1 ? false : true; KZxA\,Y'5
} _,i+gI[
5@{+V!o,
privatestaticboolean hasNextPage(int currentPage, Mn=5yU
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int totalPage){ S"z cSkF
return currentPage == totalPage || totalPage == ]$vJK
<?I s ~[2
0 ? false : true; P6E=*^^m(
} +L$,jZqS
Kx;DmwX-
OJ'x>kE
} U|%y`PZ
k<M~co;L
aumXidbS
o,sw[
T"GuE[?a
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 /@H2m\vBX
joN}N }U
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Z{w{bf1&A
kH43 T
做法如下: ;Q]j"1c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %YaUc{.%
^3-Wxn9&
的信息,和一个结果集List: ;^,2
Qs M
java代码: Y)@PGxjz
]/+qM)F
u%7a&1c
/*Created on 2005-6-13*/ hCLXL
package com.adt.bo; QxGQF|
p]zYj >e
import java.util.List; 47iwb
#dLp<l)
import org.flyware.util.page.Page; #f'(8JjY
Y"uFlHN&i
/** Jb~ -)n2
* @author Joa E00zf3Jgv'
*/ UEq;}4Bo
publicclass Result { I>27U<PX
aqb;H 'F
private Page page; J9LS6~
7
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private List content; X'&$wQ6,K
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/** / -=(51}E
* The default constructor %(-YOTDr
*/ -%=StWdb
public Result(){ i;0`d0^
super(); ,<lxq<1I
} ~PNO|]8j
."Yub];H
/** xrT_ro8
* The constructor using fields j}R4mh
* JXlFo3<
* @param page v`hv5wQ
* @param content n;"4`6L~
*/ L!L/QG|wdf
public Result(Page page, List content){ xaerMr
this.page = page; a{h(BI^~
this.content = content; #^Dc:1,
} SPV'0* Z
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/** Ar sMqb
* @return Returns the content. 34C
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*/ mm=Y(G[_%y
publicList getContent(){ ucj )t7O
return content; %6<Pt
} O#7ldF(
2t { Cpw
/** s8|#sHT
* @return Returns the page. A*pihBo7
*/ 2H<?
public Page getPage(){ Xh]\q)
return page; b,a\`%m}
} ^+[o+
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/** 1#qCD["8
* @param content LM'` U-/e$
* The content to set. +29;T0>a
*/ ~,e!t.339
public void setContent(List content){ t%z7#}9$
this.content = content; IQ{Xj3;?y
} V8&/O)} o
L1Q QU
/** ]@J}f}Mjo
* @param page @`.u"@
* The page to set. (r[<g*+3
*/ A2&&iL=j/
publicvoid setPage(Page page){ f
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this.page = page; =zA=D.D2
} oz5o=gt7
} LO61J_J<
YLd
5
d L%E0o
i`]M2Q
|V9%@
Y?
2. 编写业务逻辑接口,并实现它(UserManager, %Y Rg1UKY
*Kzs(O
UserManagerImpl) @@|E1'c7
java代码: M]` Q4\
GP1>h.J
a`pY&xq::
/*Created on 2005-7-15*/ eZHzo
package com.adt.service; <Awx:lw.
0K3FH&.%
import net.sf.hibernate.HibernateException; ($(1KE
*vAOUqX`x
import org.flyware.util.page.Page; om_&|9B)
h.=B!wKK
import com.adt.bo.Result; uWnS<O
['km'5uZ^
/** Rg[e~##
* @author Joa >!)VkDAG
*/
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publicinterface UserManager { jZ
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public Result listUser(Page page)throws .;KupQ;*
u}%&LI`.
HibernateException; |I\A0a a
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} }BogE$tc
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_SP
u`=~K
3sZK[Y|ax
f[}SS]d:E
java代码: @$+[IiP
?ha}#
:
m5u=:t
/*Created on 2005-7-15*/ :s'%IGy>:
package com.adt.service.impl; 93WYZNpX
~v54$#CB
import java.util.List; BWPYHWW}E
NUnP'X=J,
import net.sf.hibernate.HibernateException; a+~o: 5
l wg.'<
import org.flyware.util.page.Page; ;W+-x]O
import org.flyware.util.page.PageUtil; Z],"<[E
_5m }g!
import com.adt.bo.Result; 8&UuwZ6i-
import com.adt.dao.UserDAO; <aHt6s'
import com.adt.exception.ObjectNotFoundException; GO)rpk9
import com.adt.service.UserManager; /MU<)[*Ro
>(*jbL]p
/** f<;9q?0V F
* @author Joa -KNJCcBJ
*/ a;S^<8
publicclass UserManagerImpl implements UserManager { UUU^YT \
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private UserDAO userDAO; |TUpv*pq
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/** ^r& {V"l]
* @param userDAO The userDAO to set. ?0(B;[xEJ
*/ ;&!dD6N
publicvoid setUserDAO(UserDAO userDAO){ #]
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this.userDAO = userDAO; U KJY.W!w4
} Q]7Q
2DC#PX)i
/* (non-Javadoc) 3
#wj-
* @see com.adt.service.UserManager#listUser ;p_X7N
!xc7~D@om(
(org.flyware.util.page.Page) kxmS
*/ |K_B{v.
public Result listUser(Page page)throws f!J^vDl
^`!Daqk
HibernateException, ObjectNotFoundException { $"FdS,*qKl
int totalRecords = userDAO.getUserCount(); F:@Ixk?E
if(totalRecords == 0) }6bLukv
throw new ObjectNotFoundException $ vjmW!
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$~YuS_sYg
("userNotExist"); c~'kW`sNV
page = PageUtil.createPage(page, totalRecords); @iRVY|t/
List users = userDAO.getUserByPage(page); -&EmEXs%
returnnew Result(page, users); JgB# EoF
} heKI<[8l
2$o[
} 0/ Ht;(
'oHR4O*
_Nn!SE
.;:xx~G_Q
:}JZKj!}M
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 JB(;[# '~
R,\
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询,接下来编写UserDAO的代码: 0c5_L6_z
3. UserDAO 和 UserDAOImpl: ZH(.|NaH
java代码: 1;P\mff3Y
HIq1/)
W =zG
/*Created on 2005-7-15*/ g=C<E2'i*
package com.adt.dao; |u{QI3#'
+mA=%?l
import java.util.List; 4B]61|A
6\3k0z
import org.flyware.util.page.Page; [KH?5C
Du>HF;Fv
import net.sf.hibernate.HibernateException; 3I5WDuq
QRlzGRueR&
/** Ng"vBycy
* @author Joa i-?zwVmn
*/ @;6}xO2
publicinterface UserDAO extends BaseDAO { cWc)sb
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publicList getUserByName(String name)throws #FB>}:L{h*
[!&k?.*;<
HibernateException; A,{D9-%
xiF%\#N
publicint getUserCount()throws HibernateException; M: "ci;*$
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publicList getUserByPage(Page page)throws 17cW8\
'u[o`31.
HibernateException; (g m^o{
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} uC(S`Q[Bg
2]9<%-=S
@WHd(ka!
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O
FA9e(Ha
java代码: ?Q)Z..7
C/waH[Yzan
n ;5?^Un%
/*Created on 2005-7-15*/ s7o*|Xv
package com.adt.dao.impl; z[%v_S
t4/eB<fP
import java.util.List; g
u =fq\`
23$hwr&G\
import org.flyware.util.page.Page; 9'q /&uH
)_e"Nd4
import net.sf.hibernate.HibernateException; E$tk1SVo
import net.sf.hibernate.Query; a{HgIQg_>R
' 1'1T5x~
import com.adt.dao.UserDAO; y] ]Vp~R:[
8.Ef 5-m
/** Z034wn\N
* @author Joa S1juAV=
*/ |D`b7h
public class UserDAOImpl extends BaseDAOHibernateImpl 4VJzs$
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implements UserDAO { {2k<
k(,
|C6(0fgWd
/* (non-Javadoc) [RFK-E
* @see com.adt.dao.UserDAO#getUserByName 1+tt'
qm8n7Z/
(java.lang.String) 60%~+oHi~
*/ Z*(!`,.bB
publicList getUserByName(String name)throws +'j*WVE%5
8+|V!q
HibernateException { Gx_`|I{P
String querySentence = "FROM user in class O;BMwg_7
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com.adt.po.User WHERE user.name=:name"; 1X"H6j[w
Query query = getSession().createQuery _2X6bIE
*_/eAi/WG
(querySentence); 4a.e
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query.setParameter("name", name); ]7S7CVDk4
return query.list(); FHNuMdFn
} lDPRn~[#\
JeTrMa 2
/* (non-Javadoc) 2}`V c{\
* @see com.adt.dao.UserDAO#getUserCount() 9g&)6,<
*/ 76_8e{zbr
publicint getUserCount()throws HibernateException { v(@+6#&
int count = 0; JIbzh?$aD
String querySentence = "SELECT count(*) FROM .`Old{<
`b#nC[b6|v
user in class com.adt.po.User"; Z_V&IQo-7
Query query = getSession().createQuery w[YkTv
v`+n`DT
(querySentence); _2gT1B
count = ((Integer)query.iterate().next jU4)zN/`r
$,&gAU
()).intValue(); :^-HVT)qF
return count; ? W2I1HEy
} FM"GK '
COan)<Ku
/* (non-Javadoc) nL+YL
* @see com.adt.dao.UserDAO#getUserByPage W:{PBb"x8
)>/j&>%
(org.flyware.util.page.Page) >xU72l#5
*/ 3vRLg b
publicList getUserByPage(Page page)throws rtYb"-&
~E3SC@KL
HibernateException { C:s^s
String querySentence = "FROM user in class `hK>bHj
=N*%f%
com.adt.po.User"; ND e[2
Query query = getSession().createQuery mHI4wS>()+
D?\"
(querySentence); k67i`f=
query.setFirstResult(page.getBeginIndex()) XMeL^|D
.setMaxResults(page.getEveryPage()); /]k ,,&
return query.list(); *2"bG1`
} &3 XFgHo
^T}}4I_Y
} 8tT&BmT
GLaZN4`
c>u>Pi;Z
eHR&N.2
<i:*p1#Bm
至此,一个完整的分页程序完成。前台的只需要调用 hyk|+z`B
H)j[eZP
userManager.listUser(page)即可得到一个Page对象和结果集对象 _>jrlIfc
;9p#xW6
的综合体,而传入的参数page对象则可以由前台传入,如果用 =q"w2b&
KD%xo/Z.
webwork,甚至可以直接在配置文件中指定。 EU^}NZW&v:
RWh9&O:6'
下面给出一个webwork调用示例: J3lG"Ww
java代码: iL7-4Lv#
9&O#+FU
e8XM=$@
/*Created on 2005-6-17*/ y(/jTS/hd
package com.adt.action.user; Xc8= 2n
JK(`6qB>(6
import java.util.List; up+.@h{
?dJ/)3I%F
import org.apache.commons.logging.Log; zt)p`kd D
import org.apache.commons.logging.LogFactory; Vp(D|}P
import org.flyware.util.page.Page; cotxo?)Zv
TdNuD V
import com.adt.bo.Result; -!'Oy%a#
import com.adt.service.UserService; {(m+M
import com.opensymphony.xwork.Action; {2}tPT[a(
R
"/xne
/** Wz6]*P`qv
* @author Joa B^8ZoF
*/ >G-8FL
publicclass ListUser implementsAction{ _XH4;uGg
AkYupP2]v
privatestaticfinal Log logger = LogFactory.getLog z9k*1:
KAj"p9hq+k
(ListUser.class); LPq*ZZK
,h%D4EVx
private UserService userService; m%e^&N#%6r
}j+~'O4m
private Page page; kP!%|&w;
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UB
privateList users; XPHQAo[(s
JYZ2k=zh
/* k%EWkM)?
* (non-Javadoc) cPA~eZbX
* 8 *4@-3Sx
* @see com.opensymphony.xwork.Action#execute() nuf@}W>y
*/ ;yk9(wea}"
publicString execute()throwsException{ azao`z
Result result = userService.listUser(page); );Tx5Z}
page = result.getPage(); dIoF ~8V
users = result.getContent(); /_NkB$&
return SUCCESS; BKa A=Bl
} .@y{)/
fC=fJZU7$
/** Jn@Z8%B@Z
* @return Returns the page. .yZK.[x4
*/ l\K%
public Page getPage(){ Cr'
!"F
return page; Iv'RLM
} NY4!TOp
j`>?"1e@x
/** 4 hL`=[AB
* @return Returns the users. 5,F;j<F
*/ Bj;\mUsk
publicList getUsers(){ LiiK3!^i
return users; 4st~3,lR$
} t{+M|Y
o)0C-yO0qf
/** 77+|#<J
* @param page /uK)rG
F
* The page to set. Bs_S.JP<`
*/ KjO-0VMN3
publicvoid setPage(Page page){ gsnP!2cR
this.page = page; X7e>Z)l
} qIB>6bv#x
x$~3$E
/** U'rr?,RML
* @param users A|2 <A
!
* The users to set. :9(3h"
*/ L30>|g
publicvoid setUsers(List users){ 2>\b:
this.users = users; pNP_f:A|
} {d| |q<.-
7raSf&{&6b
/** YkSuwx@5_q
* @param userService ZH\0=l)
* The userService to set. @/9>=#4c
*/ - oU@D
publicvoid setUserService(UserService userService){ [ }{w
this.userService = userService; ):/,w!1
} iwvt%7
} a@Mq J=<L
B,4q>KQA
b2G2 cL-(
g4Y) Bz
iOl%-Y
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\ @19
*U
M!(
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 _8al
3 sl=>;-
么只需要: v5B"
A"N
java代码: y7>iz6N
8Bj4_!g
Dzo{PstM%
<?xml version="1.0"?> 'c#IMlv
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork oE$hqd s
hXNH"0VCV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~
W@X-
:]yg
1.0.dtd"> `Uv)Sf{
Og=[4?Kpk
<xwork> "t=UX
-3
\N? 7WQ
<package name="user" extends="webwork- Sobtz}A*
s\_l=v3
interceptors"> !z?0 :Jg
l"kxr96
<!-- The default interceptor stack name c!mG1lwD.
"@4ghot t
--> !Ri
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<default-interceptor-ref *
flW L
.?B{GnB>
name="myDefaultWebStack"/> l^ARW
E
\9'!"-i
<action name="listUser" p'gb)nI
?d4Boe0-a2
class="com.adt.action.user.ListUser"> NIaF 5z
<param YwGHG{?e
lu]o34
name="page.everyPage">10</param> #9i6+. Z
<result ujx@@N
%Z7%jma
name="success">/user/user_list.jsp</result> Gbn4*<N
</action> 3524m#4&@
Qo.Uqz.C
</package> vGMJ ^q
_PV*lK=
</xwork> mW~P!7]
U_l7CCK +
G,=F<TnI'
Hng!'
7D
#I;D
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 qcYNtEs*c
y+A{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。 Rjq a_hxrS
%J _ymJ'pd
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 i|S:s
p0Gk j-
+RS$5NLH
5KJ%]B(H2
e=7W7^"_
我写的一个用于分页的类,用了泛型了,hoho &+G;R
+bUW!$G
java代码: '#W_boN
W^k,Pmopy
iV!@bC,
package com.intokr.util; 5}XvL'
1q]&7R
import java.util.List; ) "[HZ/
5,R`@&K3D
/** NF mc>0-
* 用于分页的类<br> p,;mYm s
* 可以用于传递查询的结果也可以用于传送查询的参数<br> j=9ze op
%
* 2d 8=h6
* @version 0.01 6{.J:S9n
* @author cheng !R6ApB4ZI
*/ (ii(yz|
public class Paginator<E> { s/t11;
privateint count = 0; // 总记录数 4-V)_U#8
privateint p = 1; // 页编号 036[96t,F
privateint num = 20; // 每页的记录数 t8/%Dgu
privateList<E> results = null; // 结果 yj
zK.dM
~RInN+N#
/** @VK6JjIq
* 结果总数 VoM6
*/ @1bH}QS
publicint getCount(){ CW-A e
return count; _*E!gPO
} #ib^Kg
c+2sT3).D
publicvoid setCount(int count){ a+Ab]m8`
this.count = count; 63M=,0-Qt
} +c) TDH
Y)Tl<
/** =X@o@1
* 本结果所在的页码,从1开始 f-D>3qSS
* p411 `]Zf
* @return Returns the pageNo. b#a@rh
*/ ,r`UBQ}?
publicint getP(){ /2XW
return p; o @KW/RN"
} LuS+_|]x
k ZxW"2
/** k>5 O`Y:
* if(p<=0) p=1 R=M!e<'
* /M@PO"
* @param p :YNp8!?T?
*/ V!&P(YO:
publicvoid setP(int p){ si(cOCj/
if(p <= 0) 6 P*O&1hv
p = 1; sS9%3i/>
this.p = p; TzKK;(GX
} wkBL=a
3?`"
/** ?WHy0x20
* 每页记录数量 #epy%>
*/ p`P~i&_
publicint getNum(){ mCdgKr|n
return num; aWGon]2p
} EB,4PEe:
1'O0`Me>#
/** Im)EDTm$
* if(num<1) num=1 Uc&iZFid2K
*/ C-w5KW
publicvoid setNum(int num){ mQr0sI,o]
if(num < 1) 8\#
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num = 1; >emcJVYV`[
this.num = num; *||d\peQ
} g_z/{1$
t&}6;z 3
/** y LM"+.?pL
* 获得总页数 rMp9jG@3
*/ /;oqf4MF
publicint getPageNum(){ u
#~;&D*q
return(count - 1) / num + 1; 5<+KR.W
} K5k?H
h{_*oBa
/** 0m)&YFZ[(
* 获得本页的开始编号,为 (p-1)*num+1 4l @)K9F
*/ AIZBo@xg
publicint getStart(){ Fn+?u
return(p - 1) * num + 1; v}[dnG
} \#6Fm_b]u
A-uB\ L
/** 98=la,^$
* @return Returns the results. ?WFh',`:
*/ |vu>;*K
publicList<E> getResults(){ i9m*g*"2
return results; b$-e\XB!
} -JV~[-,
]KuMz p!
public void setResults(List<E> results){ ]'h; {;ug
this.results = results; XG 0v
} VQxpN 1
vAi$[p*im
public String toString(){ *>."V5{;S
StringBuilder buff = new StringBuilder y%cO#P@
ZjVWxQ
(); L1#Ij#
buff.append("{"); bx}fj#J]En
buff.append("count:").append(count); p#@Z$gTH`'
buff.append(",p:").append(p); O#_b7i
buff.append(",nump:").append(num); <Kt3PyF
buff.append(",results:").append ^gYD*K!*
CxF-Z7 '
(results); ~cqryr9
buff.append("}"); P Sx304
return buff.toString(); g/Wh,f3
} i::\Z$L";i
n&Yk<
} _*6v|Ed?
ziEz.Wn"
nII^mg~