Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 5H'Iul<Os
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 qKSR5 #
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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 WiH8j$;xu
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 8K^#$,.."
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分页支持类: RrLj5 Jq
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java代码: _W@sFv%sj
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package com.javaeye.common.util; 3N]ushMO
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import java.util.List; !pfpT\i]N:
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publicclass PaginationSupport { "[/W+&z[~
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publicfinalstaticint PAGESIZE = 30; g3s5ra[
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privateint pageSize = PAGESIZE; ,1~B7Zd
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privateList items; =H: N!!:
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privateint totalCount; Zk7!CJVM
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privateint[] indexes = newint[0]; P:J|![
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privateint startIndex = 0; G;u 6p
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public PaginationSupport(List items, int ZT"vVX-)G
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totalCount){ uih8ZmRt
setPageSize(PAGESIZE); lhQMR(w^
setTotalCount(totalCount); `4ga~Ch
setItems(items); [6\O
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setStartIndex(0); bs}SFT L
} fx:vhEX
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public PaginationSupport(List items, int HI1|~hOb'
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totalCount, int startIndex){ 'oGMr=gp<&
setPageSize(PAGESIZE); a^G>|+8
setTotalCount(totalCount); ">B&dNrt
setItems(items); s o: o
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setStartIndex(startIndex); }.u[';q]S
} +-x+c:
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ BGNZE{K4"
setPageSize(pageSize); xn=mS!"1Zo
setTotalCount(totalCount); o8g]ho
setItems(items); H
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setStartIndex(startIndex); "1dpv\
} )#Ecm<.^
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publicList getItems(){ lib^JJF
return items; (w_b
} dtQ3iuV %
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publicvoid setItems(List items){ )MV `'i
this.items = items; ?mi}S${g
} `&)
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publicint getPageSize(){ 1)e[F#|
return pageSize; b;`MHEzw&q
} '[[IalQ?
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publicvoid setPageSize(int pageSize){ zzC{I@b
this.pageSize = pageSize; /^i_tLgb
} nbw8YO(=
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publicint getTotalCount(){ t[({KbIy
return totalCount; / H GPy
} Qm[ ) [M
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publicvoid setTotalCount(int totalCount){ %h_N%B$7c1
if(totalCount > 0){ D1]?f`
this.totalCount = totalCount; .i7"qq.M
int count = totalCount / ;M+~e~
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pageSize; -hK^ *vJ
if(totalCount % pageSize > 0) )
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count++; SQ/}K8uZ
indexes = newint[count]; G{+zKs}~
for(int i = 0; i < count; i++){ gYpFF=7j<@
indexes = pageSize * %~dn5t;
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} gxDyCL$h3
}else{ 1"l48NL L|
this.totalCount = 0; b^~4 k; <
} I'J-)D`
} JFRbWQ0
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publicint[] getIndexes(){ meD83,L~N
return indexes; kCZ'p
} Fe2iG-ec
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publicvoid setIndexes(int[] indexes){ ?+]
this.indexes = indexes; k
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} sEa| 2$
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publicint getStartIndex(){ SR4 mbQ:
return startIndex; &61h*s
} -9 |)O:
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publicvoid setStartIndex(int startIndex){ :K*/
if(totalCount <= 0) EP{ji"/7[
this.startIndex = 0; AB.ZmR9|
elseif(startIndex >= totalCount) ) Cm95,Y
this.startIndex = indexes {ZUgyGE{
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[indexes.length - 1]; TaG(sRI
elseif(startIndex < 0) $3Sm?
this.startIndex = 0; @ +>>TGC
else{ nI`9|W
this.startIndex = indexes hC!8-uBK5<
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[startIndex / pageSize]; vf!lhV-UG+
} -+Ox/>k
} ocj^mxh=O
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publicint getNextIndex(){ :<6gP(
int nextIndex = getStartIndex() + _nIt4l7
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pageSize; xqj@T^y
if(nextIndex >= totalCount) E**Hu 9
return getStartIndex(); _dVA^m
else 69Q#UJ
return nextIndex; _.GHtu/I
} +qa^K%K
`9DW}
publicint getPreviousIndex(){ cw;TIx_q
int previousIndex = getStartIndex() - DPWnvd
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pageSize; NV18~5#</
if(previousIndex < 0) xf3/J{n3
return0; &A&2z l %#
else \lpvRZ\L&g
return previousIndex; 9!Bz)dJ3
} jrO{A3<E
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} Mgux(5`;
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抽象业务类 <xD6}h/
java代码: j2%M-y4E
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Hy2~D:34
/** xtd1>|
* Created on 2005-7-12 EE~DU;p;]
*/ AgJPtzs
package com.javaeye.common.business; Gr|102
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import java.io.Serializable; 9t{Iv({6p
import java.util.List; ghaO#kI
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import org.hibernate.Criteria; ;/(<yu48
import org.hibernate.HibernateException; q}p
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import org.hibernate.Session; z4s{a(Tsd
import org.hibernate.criterion.DetachedCriteria; 26-K:"
import org.hibernate.criterion.Projections; QqB9I-_
import !@f!4n.e|I
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org.springframework.orm.hibernate3.HibernateCallback; . L]!*
import Vdb X4^V
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org.springframework.orm.hibernate3.support.HibernateDaoS K;~I;G
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upport; 6;}W)S
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import com.javaeye.common.util.PaginationSupport; ,M9Hdm
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public abstract class AbstractManager extends g:[yA{Eh
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HibernateDaoSupport { MMyJAGh
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privateboolean cacheQueries = false; Ehg(xK
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privateString queryCacheRegion; T@on
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publicvoid setCacheQueries(boolean @HP7$U"
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cacheQueries){ {GQRJ8m
this.cacheQueries = cacheQueries; %g=SkQ&d
} F44KbUH
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publicvoid setQueryCacheRegion(String Xs$UpQo
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queryCacheRegion){ ]t.6bb4
this.queryCacheRegion = 8i?:aN[.1b
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queryCacheRegion; u*<knZ~ty
} J+f*D+x1
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publicvoid save(finalObject entity){ )\l(h%s[I
getHibernateTemplate().save(entity); 7Ezy-x2h
} ,&rHBNS
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publicvoid persist(finalObject entity){ 6e At`L[K.
getHibernateTemplate().save(entity); :eW`El
} MI|anM
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publicvoid update(finalObject entity){ nQ^ c{Bm:
getHibernateTemplate().update(entity); yq\p%z$:
} |eFce/
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publicvoid delete(finalObject entity){ |Fp+9U
getHibernateTemplate().delete(entity); pcO0xrI
} oC1Nfc+
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publicObject load(finalClass entity, P^& =L&U
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finalSerializable id){ #@K
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return getHibernateTemplate().load 9 az{j1
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(entity, id); {K >}eO:K
} ]Qh0+!SdG
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publicObject get(finalClass entity, \LQ54^eB
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finalSerializable id){ W60C$*h
return getHibernateTemplate().get +|TFxaVz
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(entity, id); Eh/Z4pzT
} eaCh;IpIf
@_C?M5v
publicList findAll(finalClass entity){ p2uZ*sY(D
return getHibernateTemplate().find("from oTLpq:9J
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" + entity.getName()); f,'9Bj.~
} 1_6oM/?'
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publicList findByNamedQuery(finalString ?Y\hC0a60
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namedQuery){ ,K~r':ht
return getHibernateTemplate S_dM{.!Z(,
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().findByNamedQuery(namedQuery); T6fm`uL&L
} @w5x;uB|%G
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publicList findByNamedQuery(finalString query, [7@9wa1v!
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finalObject parameter){ )lDmYt7me
return getHibernateTemplate kNrN72qg
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().findByNamedQuery(query, parameter); :|PgGhW
} |%c"Avc
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publicList findByNamedQuery(finalString query, F<LRo}j"9Q
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finalObject[] parameters){ ,RIC _26
return getHibernateTemplate B"=w9w]
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().findByNamedQuery(query, parameters); 9KGi%UIFvn
} Uy5G,!
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publicList find(finalString query){ m9 D'yXZ
return getHibernateTemplate().find ]c~W$h+F
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(query); Auk#pO#
} (hFyp}jkk
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publicList find(finalString query, finalObject 5><KTya?=
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parameter){ mVNHH!
return getHibernateTemplate().find ~"}o^#@DwJ
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(query, parameter); @z1pE@7jK
}
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public PaginationSupport findPageByCriteria u;3wg`e
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(final DetachedCriteria detachedCriteria){ >dYN@cB$}
return findPageByCriteria W~qVZ(G*U
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); tiQeON-Q_
} G%5ZG$as
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public PaginationSupport findPageByCriteria qEajT"?
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(final DetachedCriteria detachedCriteria, finalint }(/\vTn*1
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startIndex){ (,OF<<OH
return findPageByCriteria cbaa*qoU
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(detachedCriteria, PaginationSupport.PAGESIZE, AtYqD<hl:
Vh'H =J
startIndex); SBh"^q
} L5 Q^cY]p
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public PaginationSupport findPageByCriteria j`:D BO&)\
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(final DetachedCriteria detachedCriteria, finalint /wT<p
y ]D[JX[
pageSize, _(:<l
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finalint startIndex){ 6'45c1e
return(PaginationSupport) WO!'("
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getHibernateTemplate().execute(new HibernateCallback(){ 8KMo !p\i
publicObject doInHibernate r<c&;*
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(Session session)throws HibernateException { Q.} guI\
Criteria criteria = fprP$MbI
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detachedCriteria.getExecutableCriteria(session); H7dT6`<~Y
int totalCount = 7^W(e s
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((Integer) criteria.setProjection(Projections.rowCount ;DXg
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()).uniqueResult()).intValue(); 2uLBk<m5c
criteria.setProjection O
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(null); za!8:(
List items = r t'pc\|O&
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criteria.setFirstResult(startIndex).setMaxResults kJK*wq]U6
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(pageSize).list(); l!mx,O`
PaginationSupport ps = W^YaC
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new PaginationSupport(items, totalCount, pageSize, ve^gzE$<I
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startIndex); NOFuX9/'w
return ps; #7['M;_
} `!Yd$=*c_&
}, true); =z[$o9
} eI,H
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public List findAllByCriteria(final |8?e4yVd
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DetachedCriteria detachedCriteria){ DR7 JEE
return(List) getHibernateTemplate K.Tob,5`
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().execute(new HibernateCallback(){ :}z`4S@b
publicObject doInHibernate JFFluL=-
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(Session session)throws HibernateException { nzU;Bi^m
Criteria criteria = xauMF~*
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detachedCriteria.getExecutableCriteria(session); X& mD/1
return criteria.list(); \03ZE^H
} HZqk)sN
}, true); gY!?JZC-0
} Cy dV$!&mP
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public int getCountByCriteria(final i>O8q%BnJ
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DetachedCriteria detachedCriteria){ J`[gE`d
Integer count = (Integer) 83J63Xa
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getHibernateTemplate().execute(new HibernateCallback(){ ![9$ru
publicObject doInHibernate [}!0PN?z~A
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(Session session)throws HibernateException { u|LDN*#DW
Criteria criteria = 0Wj,=9q
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detachedCriteria.getExecutableCriteria(session); P$Q,t2$A
return +;-ZU
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criteria.setProjection(Projections.rowCount |DYgc$2pN
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()).uniqueResult(); td7Of(k'
} &0i$Y\g
}, true); }U '
return count.intValue(); mLx=Zes:.
} d$"?8r4:K
} ,^RZ1tLz
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用户在web层构造查询条件detachedCriteria,和可选的 udXzsY9Ng
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 rp+]f\]h
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PaginationSupport的实例ps。 {Fqwr>e
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ps.getItems()得到已分页好的结果集 HX)]@qL
ps.getIndexes()得到分页索引的数组 IXG@$O?y/
ps.getTotalCount()得到总结果数 N0%q66]1
ps.getStartIndex()当前分页索引 ZZ L@UO>:
ps.getNextIndex()下一页索引 a@J/[$5
ps.getPreviousIndex()上一页索引 sY4q$Fq
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3-&~jm~"
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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 g)R 2V
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一下代码重构了。 Z~<=I }@
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我把原本我的做法也提供出来供大家讨论吧: *AP"[W
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首先,为了实现分页查询,我封装了一个Page类: mz+UkA'
java代码: fs?H
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/*Created on 2005-4-14*/ bLSc=f&
package org.flyware.util.page; ^/6P~iK'
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/** @%G?Nht]o
* @author Joa w$Fg0JS
* X&kp1Ih<^
*/ K7([Gc9
publicclass Page { DVVyWn[
;b:'i&r
/** imply if the page has previous page */ 5\=
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privateboolean hasPrePage; N.H<'Q8&
/&<V5?1|
/** imply if the page has next page */ !/!ga)Y
privateboolean hasNextPage; _6V1oe2
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/** the number of every page */ C JER&"em7
privateint everyPage; a+cDH
gb|;]mk*"
/** the total page number */ IxS%V31
privateint totalPage; iPCCTs
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/** the number of current page */ Mm(#N/
privateint currentPage; %1:caa@_p
-- FzRO{D
/** the begin index of the records by the current JSi0-S[Y{
k_!e5c
query */ fIl!{pv[
privateint beginIndex; Mn/@?K?y
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/** The default constructor */ K,I
public Page(){ k@un}}0r
w#[cGaIB
} 3fp&iz
n=bdV(?4
/** construct the page by everyPage %T\hL\L?
* @param everyPage 8*@{}O##
* */ huS*1xl
public Page(int everyPage){ \ ZE[7Ae
this.everyPage = everyPage; pA8As
} W>i"p~!
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/** The whole constructor */ U: Wet,
public Page(boolean hasPrePage, boolean hasNextPage, YcX\t6VK
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int everyPage, int totalPage, ?h&?`WO(
int currentPage, int beginIndex){ Hcwfe=K&/
this.hasPrePage = hasPrePage; J-Tiwl
this.hasNextPage = hasNextPage; Zi.' V
this.everyPage = everyPage; ON){d!]uJ
this.totalPage = totalPage; P3: t
4^
this.currentPage = currentPage; Hj|&P/jY]*
this.beginIndex = beginIndex; 4&;iORw&E4
} BhzD V
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/** QcW8A ,\q
* @return 3_Xu3hNH!
* Returns the beginIndex. >>,G3/Zd*
*/ d_M+W@{
publicint getBeginIndex(){ w\YS5!P,V
return beginIndex; ,d,2Q
} 8ZVQM7O
a
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/** %Qlc?Wl:
* @param beginIndex M|K^u.4
* The beginIndex to set. h7!O
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*/ %z-*C'j5H
publicvoid setBeginIndex(int beginIndex){ HyU: BW;
this.beginIndex = beginIndex; rO$pj~!|Q
} =I546($
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/** LCH\;07V#
* @return w CB*v<*
* Returns the currentPage. v={{$=/t
*/ KDq="=q
publicint getCurrentPage(){ o~IAZU39
return currentPage; ~qrSHn}+PU
} e))L&s
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/** &Y=0 0
* @param currentPage n jWe^
* The currentPage to set. o+A1-&qhN
*/ W&*&O,c
publicvoid setCurrentPage(int currentPage){ z{
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this.currentPage = currentPage; 'R79,)|;[
} p>`rTaeZg
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/** () _RLA
* @return B/1j4/MS
* Returns the everyPage. Oh*~+/u}q
*/ r
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publicint getEveryPage(){ {fzX2qMZ]
return everyPage; w}>%E6UY
} gmRc4o
}q.D)'g_
/** 5]N0p,f
* @param everyPage 7@fS2mu
* The everyPage to set. #5@(^N5p`
*/ lx%c&~.DiB
publicvoid setEveryPage(int everyPage){ M\C9^DX{
this.everyPage = everyPage; fd&Fn=!
} q()o|V
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/** /GIGE##1F
* @return xo_STLAw
* Returns the hasNextPage. rMDvnF
*/ rF-SvSj}
publicboolean getHasNextPage(){ *#mmk1`
return hasNextPage; RW. qw4
} 9efDM
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/** K
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* @param hasNextPage 6DHK&<=D8
* The hasNextPage to set. +?{"Q#.>;
*/ mrP48#Y+l
publicvoid setHasNextPage(boolean hasNextPage){ S{+t>en
this.hasNextPage = hasNextPage; 0!\C@wnH
} l/'GbuECm
f=F:Af!
/** A*y4<'}<
* @return 2d[q5p
* Returns the hasPrePage. Xxg|01
*/ V/ G1C^'/
publicboolean getHasPrePage(){ 73cb1kfPd
return hasPrePage; Trv}YT.
} AOR?2u
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/** Y\]ZIvTSb
* @param hasPrePage )}@D\(/@
* The hasPrePage to set. avRtYL
*/ cAW}a
publicvoid setHasPrePage(boolean hasPrePage){ Vke<; k-
this.hasPrePage = hasPrePage; *(OG+OkC
} dw"Es;^
oe|#!SM(
/** 6dIPgie3w
* @return Returns the totalPage. \)~d,M}kK
* !<p,G`r
*/ u5oM;#{@-
publicint getTotalPage(){ |2j,
return totalPage; =
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} >a?Bk4w
v1OVrk>s>
/** fvC,P#z'|
* @param totalPage Tz @=N] D
* The totalPage to set. J?8Mo=UZz
*/ BIWe Hx
publicvoid setTotalPage(int totalPage){ d+q],\"R
this.totalPage = totalPage; duY?LJ @g
} {cXr!N^K
&>JP.//spi
} oP`l)`
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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 Z}+}X|
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个PageUtil,负责对Page对象进行构造: NU=ru/
java代码: HOP*QX8C%
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/*Created on 2005-4-14*/ .4+Rac
package org.flyware.util.page; JsJP%'^/R
<w2h@ea
import org.apache.commons.logging.Log; }=-0DSLVj
import org.apache.commons.logging.LogFactory; '=_(fa,
yvYMk(LSF
/** f% pT-#
* @author Joa *dw.=a9
* e|]e\Or>
*/ pm6#azQ
publicclass PageUtil { p) 8S]p]
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privatestaticfinal Log logger = LogFactory.getLog r2=@1=?8
)5}<@Ql
(PageUtil.class); V`I4"}M1
7}kJp%-
/** ! ?g+'OM
* Use the origin page to create a new page ix!xLm9\
* @param page m/=nz.
* @param totalRecords A=N$5ZJ
* @return +RooU?Aq
*/ 7:jLZ!mgi
publicstatic Page createPage(Page page, int =1IK"BA2?
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totalRecords){ sW]_Ky.]
return createPage(page.getEveryPage(), m;@q('O
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page.getCurrentPage(), totalRecords); =
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} 6("_}9ZOc
?:"ABkL|+Y
/** 6
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* the basic page utils not including exception n28JWkK8
[dJ!JT/X{
handler rwP#Yj[BK+
* @param everyPage I"Zp^j
* @param currentPage K<>kT4
* @param totalRecords e5'I W__
* @return page h4;kjr}h}
*/ jK w
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publicstatic Page createPage(int everyPage, int G2`z?);1b
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currentPage, int totalRecords){ `c
everyPage = getEveryPage(everyPage); y!FO
currentPage = getCurrentPage(currentPage); | b'Ut)E
int beginIndex = getBeginIndex(everyPage, E%mEfj7
nfEbu4|
currentPage); W==~9
int totalPage = getTotalPage(everyPage, 2R/|/>T v
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totalRecords); LF7-??'
boolean hasNextPage = hasNextPage(currentPage, I*u3e
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totalPage); @:>"VP<(
boolean hasPrePage = hasPrePage(currentPage); @]Cg5QW>T
cN,*QN
returnnew Page(hasPrePage, hasNextPage, @DysM~I
everyPage, totalPage, :q9!
currentPage, ~i.*fL_Y
<],{at` v
beginIndex); H>TO8;5(
} @](vFb
!T0I; j&
privatestaticint getEveryPage(int everyPage){ 'z$N{p40m
return everyPage == 0 ? 10 : everyPage; Y1PR?c
Q
} bzi"7%c
q`<vY'&1
privatestaticint getCurrentPage(int currentPage){ <[dcIw<7
return currentPage == 0 ? 1 : currentPage; & zDuh[j}
} U6.aoqb%
&4?&tGi
privatestaticint getBeginIndex(int everyPage, int z!}E2j_9P
6
U.Jaai:
currentPage){ 2 @#yQB1
return(currentPage - 1) * everyPage; tguB@,O
} 5JzvT JMx
n>'(d*[e&
privatestaticint getTotalPage(int everyPage, int S=qh7ML
^j}C]cq{Xg
totalRecords){ F-m%d@P&X
int totalPage = 0; !rnjmc
YmV/[{
if(totalRecords % everyPage == 0) Hx.|5n,5
totalPage = totalRecords / everyPage; Q|_F
P:
else ~]KdsT(=_
totalPage = totalRecords / everyPage + 1 ; k|;a"56F
JxVGzb`8
return totalPage; (|QJ[@?q
} !Tnjha*
0Ui.nz j
privatestaticboolean hasPrePage(int currentPage){ $TUYxf0q
return currentPage == 1 ? false : true; u&zY>'}zm
} 5 ^{~xOM5
3ahriZe
privatestaticboolean hasNextPage(int currentPage, R$&;
m.<_WXH
int totalPage){ B!RfPk1B<*
return currentPage == totalPage || totalPage == u zZ|0
Xh"9Bcjf
0 ? false : true; Ks.b).fH
} ](r}`u%}y
j,YrM?Xdo
tT]@yo|?e/
} 6"-$WUlg
nb_/1{F
5%,3)H{;t
r^
r+h[V
_}R$h=YD
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。 Z
'5itN^
k~[jk5te
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 fK/:
45yP {+/-Q
做法如下: K,S4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 3fOOT7!FL
p(yv
的信息,和一个结果集List: tD8fSV
java代码: /zIG5RK>
kz=ho~ @
3bRxV
@0.
/*Created on 2005-6-13*/ Gk:fw#R
package com.adt.bo; NM. e4
o0r&w;!
import java.util.List; Ct=bZW"j/
VEWW[T
import org.flyware.util.page.Page; 4%0s p
hW*o;o7u
/** kQ+y9@=/g
* @author Joa PZ]tl
*/ 5_9`v@-4_
publicclass Result { xkSX KR
;.h /D4
private Page page; |V34;}\4
n.+*_c8 k
private List content; @<W` w
Iy)1(upM
/** Jh+;+"
* The default constructor 24wDnDyh
*/ pm
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public Result(){ Bl\:YYd
super(); vQ<
~-E
} TuwP'g[
'n|U
/** 6J;!p/C8E
* The constructor using fields D`XXR}8V
* ;@;aeu
* @param page wUvE
* @param content jIKg* @
*/ n@pwOHQn<|
public Result(Page page, List content){ ed'[_T}T3t
this.page = page; c]pz&
this.content = content; \S h/<z
} <EC"E #p
aImzK/
/** )"TVR{I%B
* @return Returns the content. {C w.?JU
*/ %M
x|"ff
publicList getContent(){ q^[t</_N
return content; e;6:U85LS
} `}Y)l:G*g
AE~zmtW
/** )WvKRp r
* @return Returns the page. CaYb}.:AX
*/ JE O$v|X
public Page getPage(){ 99OZK
return page; *<\`"C;
} 89d%P
J0
xh;gAh5n
/** W'6DwV|
* @param content !oyo_h
* The content to set. 0Y oKSo
*/ v7(7WfqP
public void setContent(List content){ ;Tbo \Wp9
this.content = content; her>L3G-E
} 3nA^s"#p
#ed|0
/** sm18u-
* @param page A^aY-V
* The page to set. C).\ J !
*/ @Z/jaAjUC
publicvoid setPage(Page page){ F
w{:shC
this.page = page; ]v<8l4p;
} hT%fM3|,e
} NLZ5 5yo$
_4oAk @A
^mC~<pP(
=Ji[ ;wy@
.$~3RjM
2. 编写业务逻辑接口,并实现它(UserManager, i?^L",[
2wpJ)t*PF
UserManagerImpl) 7"|Qmyb
java代码: ]O;*Y{:Y
Wl3S]4A
^S|qGu,G
/*Created on 2005-7-15*/ /US% s
package com.adt.service; &_3#W.w~Z
;8[VCU:
import net.sf.hibernate.HibernateException; QYH#WrIVx
Ht.P670
import org.flyware.util.page.Page; huqtk4u
A^}#
import com.adt.bo.Result; ql9n`?Q
u""26k51
/** X!g;;DB\
* @author Joa ?[#w*Am7
*/ TJYhgna
publicinterface UserManager { xy`Y7W=
aUL7]'q}
public Result listUser(Page page)throws DWtITO>
RV]#Bg*[#
HibernateException; >-c?+oy
7mSNz.
} 5 _y w
'A{zH{
+8<$vzB
L)M{S3q,
8}yrsF#
java代码: 4evN^es'I_
8i$|j~M a
l!gX-U%-
/*Created on 2005-7-15*/ `Fcr`[
package com.adt.service.impl; "(jD*\8x
T=/c0#Q|q
import java.util.List; 7a>+ma\
:PV3J0pB~
import net.sf.hibernate.HibernateException; ~> )>hy)
V|A)f@ Fs
import org.flyware.util.page.Page; a6zWg7 PN
import org.flyware.util.page.PageUtil; RQ0^
1
R
,i6U*
import com.adt.bo.Result; QcWg
import com.adt.dao.UserDAO; @@@}FV&
import com.adt.exception.ObjectNotFoundException; !{,2uQXe
import com.adt.service.UserManager; 7x.j:{2
yVVyWte,
/** Dlz0*eHD
* @author Joa nYyKz
Rz
*/ H6Zo|n
publicclass UserManagerImpl implements UserManager { O!>#q4&]
xVsI#`<a
private UserDAO userDAO; h% >ZN-K)
KHP/Y{mH
/** )
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* @param userDAO The userDAO to set. Q|[^dju
*/ }!xc@
publicvoid setUserDAO(UserDAO userDAO){ !]?kvf-3e
this.userDAO = userDAO; !'!\>x$
} E4=D$hfq`
("(wap~<nD
/* (non-Javadoc) '=G6$O2
* @see com.adt.service.UserManager#listUser L_T+KaQCH
aAP86MHO
(org.flyware.util.page.Page) s5v}S'uO{
*/ "%Ief4
public Result listUser(Page page)throws
n?c[ E+i;
#"oLz"{
HibernateException, ObjectNotFoundException { i<$?rB!i<1
int totalRecords = userDAO.getUserCount(); 3w>1R>7
if(totalRecords == 0) C/
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throw new ObjectNotFoundException gc I<bY
i{9.bpp/
("userNotExist"); N
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page = PageUtil.createPage(page, totalRecords); 3rMi:*?
List users = userDAO.getUserByPage(page); \0Xq&CG=E
returnnew Result(page, users); #'@@P6o5
} 2f{p$YIt
]w,|WZm
} 16N|
7}NvO"u
S@[NKY
>mtwXmI
Zqf
ovG
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 F <iV;+
N`d%4)|{
询,接下来编写UserDAO的代码: _s<BXj
3. UserDAO 和 UserDAOImpl: 'A3*[e|OS
java代码: ]N\D^`iQ
K}N~KDW R|
G,+3(C
/*Created on 2005-7-15*/ D'%M#S0
package com.adt.dao; 'Sgz\=K
CXuMNa
import java.util.List; 9]T61Z{OW1
:3s^, g
import org.flyware.util.page.Page; ci+ajON
>`[+24e
import net.sf.hibernate.HibernateException; &*8.%qe;
Migl
/** DD
* @author Joa CX2qtI8N?
*/ 3=?,Dv0P
publicinterface UserDAO extends BaseDAO { 7k%!D"6_R
;FuST
publicList getUserByName(String name)throws (QojIdHt
2^=.f?_YR
HibernateException; Ll%}nti
6uUzky
publicint getUserCount()throws HibernateException; } gwfe
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JoG(Nk]
publicList getUserByPage(Page page)throws yW*,Llb5
vV=rBO0a?
HibernateException; [5!{>L`
pKLNBR|
} ru/{s3
KR R)pT
[ns==gDD
?
47"$=G
'
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java代码: f6\4,()
(+xT5 2
mBB"e"o
/*Created on 2005-7-15*/ ;*+H&
package com.adt.dao.impl; t+pA9^$[`
`WMU'ezF
import java.util.List; Z;tWV%F5
~$//4kES
import org.flyware.util.page.Page; JSylQ201
{md5G$*%
import net.sf.hibernate.HibernateException; MLiaCG;
import net.sf.hibernate.Query; hhWy-fP#
\QG2V$
import com.adt.dao.UserDAO; y\CxdTs
-s)h
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/** wSM(!:on5
* @author Joa B+jh|@-
*/ 8$ RiFD,
public class UserDAOImpl extends BaseDAOHibernateImpl 0"GLgj:9
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implements UserDAO { +BhJske
S{)K_x
/* (non-Javadoc) xDPR^xY
* @see com.adt.dao.UserDAO#getUserByName L&=r-\.ev
0N]\f.=`
(java.lang.String) GjN6Af~}
*/ 92C; a5s
publicList getUserByName(String name)throws 7hLh}
TI2K_'
HibernateException { 2qV oe}F
String querySentence = "FROM user in class 0DnOO0Nc
f<oU"WM
com.adt.po.User WHERE user.name=:name"; O0_RW`69
Query query = getSession().createQuery py%~Qz%
'R-g:X\{
(querySentence); f`}/^*D
query.setParameter("name", name); amX1idHo^
return query.list(); 1D!MXYgm1b
} WjSu4
?'H+u[1.
/* (non-Javadoc) l&kZ6lZ
* @see com.adt.dao.UserDAO#getUserCount() &v;o }Q}E{
*/ W4P+?c>'2
publicint getUserCount()throws HibernateException { ^ rUq{
int count = 0; J,=ZUh@M
String querySentence = "SELECT count(*) FROM sX}#L
0S&J=2D!
user in class com.adt.po.User"; mfffOG
Query query = getSession().createQuery E.0J94>iM
Jf#-OlEQ
(querySentence); 0V8 6]zSo
count = ((Integer)query.iterate().next _I3v"d
(u='&ka
()).intValue(); Lm<WT*@
return count; x&+&)d
} D
dCcsYm,
*XYp~b
/* (non-Javadoc) qUn+1.[%
* @see com.adt.dao.UserDAO#getUserByPage .LnknjC
5:5d=7WX
(org.flyware.util.page.Page)
=}I=s@
*/ Aeo=m}C;
publicList getUserByPage(Page page)throws 9x8Vsd
%BT]h3dcSS
HibernateException { u~JR]T
String querySentence = "FROM user in class a({N}ZDo
u
i$4
com.adt.po.User"; gq4X(rsyD
Query query = getSession().createQuery ,&fZo9J9
8A::q ;
(querySentence); jaavh6h)
query.setFirstResult(page.getBeginIndex()) \!w |
.setMaxResults(page.getEveryPage()); zuFPG{^\#
return query.list(); =FiO{Aw`N
} ^j10
f$B
PY3bn).uR
} ;kR=vv
3J/l>1[
)iK:BL*Nw
cW"DDm
g
zKaj<Og
至此,一个完整的分页程序完成。前台的只需要调用 bC) <K/Q9
rce._w }
userManager.listUser(page)即可得到一个Page对象和结果集对象 |;d#k+/;
4gVIuF*pS
的综合体,而传入的参数page对象则可以由前台传入,如果用 4vvQ7e7
iE_[]Vgc
webwork,甚至可以直接在配置文件中指定。 ma<uXq
6R$Yh0%
下面给出一个webwork调用示例: o-AF_N
java代码: ]ZW-`U MO
7`^Y*:(
$"MVr5q6
/*Created on 2005-6-17*/ ">20`Mj8
package com.adt.action.user; 3u+i
EAxdF
u
import java.util.List; WB<MU:.Vc
yx*<c#Uf
import org.apache.commons.logging.Log; ty4R2LnC
import org.apache.commons.logging.LogFactory; ro3%VA=V
import org.flyware.util.page.Page; -xN/H,xok
nG{o$v_|
import com.adt.bo.Result; 5~im.XfiVx
import com.adt.service.UserService; 0 VG;z#{J
import com.opensymphony.xwork.Action; :("@U,
sX*L[3!vN
/** EwuRIe;D
* @author Joa pjoyMHWK
*/ loE;q}^
publicclass ListUser implementsAction{ esQ`6i
]:']
privatestaticfinal Log logger = LogFactory.getLog D@ !r?E`
[?qzMFb
(ListUser.class); [kckE-y
.5s^a.e'O
private UserService userService; kUT^o
YU)%-V\
private Page page; G]EI!-y
0S'@(p[A
privateList users; ~Cg7
L$+_
/* ;O{bF8U
* (non-Javadoc) h+Yd
\k
* `_i|\}tl
* @see com.opensymphony.xwork.Action#execute() 5ug|crX
*/ ;volBfv
publicString execute()throwsException{ FUJ<gqL
Result result = userService.listUser(page); rwio>4=
page = result.getPage(); $/@
L
users = result.getContent(); !y>up+cRjl
return SUCCESS; `g)
} B*Om\I
vW!O("\7K<
/** UugR
* @return Returns the page. K=}Eupn=
*/ v&d'ABeT
public Page getPage(){ 2mMi=pv9
return page; ,=c(P9}^
} Q>9bKP
1;i|GXY:h
/** !>=lah$&
* @return Returns the users. U /~uu
*/ q8;MPXSG3
publicList getUsers(){ ^q0`eS
return users; 4sRg+mMI
} }m%&|:PH
$/5\Hg1
/** F< 5kcu#iL
* @param page ;T8(byH ?
* The page to set. S#He OPRL
*/ @'GPZpbvZ
publicvoid setPage(Page page){ F?6Q(mRl
this.page = page; ~x+'-2A46
} fkImX:|q
hx8pg,X
/** J7aYi]vI
* @param users /me ]sOkn
* The users to set. @p}_"BHYWt
*/ %hw4IcWJ|
publicvoid setUsers(List users){ 9^`cVjD5
this.users = users; &,:!gYN
} zxD=q5in
[Ob'E!;<
/** `kv7Rr}Q
* @param userService SDNRcSbOD6
* The userService to set. XP:fL
NpQ
*/ 55UPd#E'
publicvoid setUserService(UserService userService){ K :+q9;g
this.userService = userService; #w \x-i|
} >9i>A:
} 7ncR2-{g
pR=R{=}wV
&)JoB
\*qradgx$
NjA[(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, UJ%.KU%Q}
f8=qnY2j
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#$Pf=}
5L~lF8
么只需要: IMMsOl
java代码: xfC$u`e=
L:mE)Xq2
L;L_$hu)
<?xml version="1.0"?> }R5EuR m\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2EN}"Du]mj
Ui9;rh$1eU
1.0//EN" "http://www.opensymphony.com/xwork/xwork- I.|b:c
xN
,{msJyacmR
1.0.dtd"> d)D!np=
&m[}%e%~0
<xwork> 02tN=}Cj)
-aE,KQ
<package name="user" extends="webwork- F9r/
M"5
Tz.okCo]z
interceptors"> .d$Q5Qae
^`aw5 +S
<!-- The default interceptor stack name \ Ucv<S
cXf/
--> \-{$IC-L
<default-interceptor-ref 7bRfkKD
l,(:~KH|
name="myDefaultWebStack"/> %H&WihQ
=_g#I
<action name="listUser" a.JjbFL
|22vNt_
class="com.adt.action.user.ListUser"> `'EG7
<param qdKqc,R1{
3XQe? 2:<
name="page.everyPage">10</param> 5 $$Cav
<result X%JyC_~<
Q8QB{*4
name="success">/user/user_list.jsp</result> vdB2T2F
</action> i^Jw`eAmT
F^%\AA]8
</package> Fv$w:r]q6
Jg{K!P|i
</xwork> Y"KJ`Rx
&b*v7c=o
,,80nW9E
LikCIO
matm>3n
4x4[
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 h)j#?\KYm9
f?eq-/U R
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 w2/3[VZ}l
)K$xu (/K
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 hu"-dT;4]
0`p"7!r
!
9*l!(
(4yXr|to}
d7QUg6=
我写的一个用于分页的类,用了泛型了,hoho @(E6P;+{
&2 *
java代码: KHC Fz
AW|SD
"iX\U'`
package com.intokr.util; 4MW oGV9
m?Cb^WgcF
import java.util.List; Oj_F1.
r
DrAIQ7Jd
/** a j
.7t=^
* 用于分页的类<br> )1@%!fr
* 可以用于传递查询的结果也可以用于传送查询的参数<br> /uDcJ1u66
* gM]E8%;{
* @version 0.01 B^zg#x#8
* @author cheng Lyn{Uag
*/ ;~[}B v
public class Paginator<E> { 1tiOf~)
privateint count = 0; // 总记录数 w\N\J^5,Q
privateint p = 1; // 页编号 ^4Xsd h5
privateint num = 20; // 每页的记录数 45<gO1
privateList<E> results = null; // 结果 i!3*)-a\~`
oAB:H\
/** `nEqw/I
* 结果总数 f O+lD
*/ ?Ov~\[) F
publicint getCount(){ T@#?{eA
return count; 8*{jxN'M
} :)B1|1
}0@@_Y]CC
publicvoid setCount(int count){ s?->2gxhx
this.count = count; Y+vIU*O
} +\&6Zbn
~=[5X,Ta
/** U#iW1jPE2
* 本结果所在的页码,从1开始 ed_+bCNy
* p8YOow7)
* @return Returns the pageNo. Ik5V?
*/ ohJDu{V
publicint getP(){ M}CxCEdDB]
return p; !Yn#3c
} dhJ=+Fz"w
D/4]r@M2c
/** I!1+#0SG
* if(p<=0) p=1 0CXXCa7!
* `r3 klL,W'
* @param p bXXX-Xc
*/ gYk5}E-
publicvoid setP(int p){ ;YMg4Cs
if(p <= 0) 3$5E1*ed
p = 1; RIO?rt;
this.p = p; Mk973'K'
} 83'+q((<
{+d)M
/** ~[og\QZX
* 每页记录数量 Vmh$c*TE
*/ vRf$#fBEQ
publicint getNum(){ 7w8UnPuM
return num; |/%5~=%7
} !io1~GpKS
;C:|m7|
/** 59W~bWHCP
* if(num<1) num=1 t#y,9>6
*/
6Bcr.`
publicvoid setNum(int num){ }oSgx
if(num < 1) N$C+le
num = 1; Eaxsg
this.num = num; jAy2C&aP
} AcXVfk z
% a.T@E
/** kZrc^
* 获得总页数 )uR_d=B&
*/ +c
C.
ZOS
publicint getPageNum(){ 8JF<SQ
return(count - 1) / num + 1; >BK/HuS
} kw gLK@@%1
`VUJW]wGu
/** 2 @T~VRy
* 获得本页的开始编号,为 (p-1)*num+1 .7 LQ l?
*/
-%%Xx5D
publicint getStart(){ Sj|tR[SAoD
return(p - 1) * num + 1; EEK!'[<,sE
} pYr+n9)^
zks7wt]A
/** .sM,U
* @return Returns the results. x{K"z4xbI
*/
dtfOFag4_
publicList<E> getResults(){ IO=$+c
return results; $_TS]~y4}
} UF }[%Sa
&=n/h5e0t&
public void setResults(List<E> results){ %xQ'i4`
this.results = results; 2e-bt@0t
} <%m1+%mA.
p9u'nDi
public String toString(){ R4JfH
StringBuilder buff = new StringBuilder ElDeXLr'
j&Xx{ 4v
(); G%>[7 ]H
buff.append("{"); Wq5}LO)
buff.append("count:").append(count); /^\E:(RH
buff.append(",p:").append(p); <-n^h~,4
buff.append(",nump:").append(num); TBOg.y]
buff.append(",results:").append ZnzO]
Kz/,V6H:
(results); >qr/1mW
buff.append("}"); [{GN#W|AGP
return buff.toString(); SDE$ymPx
} GRkN0|ovfj
|>'N^
} Meep
*l"CIG'
zn&ZXFgN