Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 z3}4+~~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 8<ri"m,
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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 $VJ=A<
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ph1veD<ZZ
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分页支持类: \+w -{"u$
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java代码: aKCXV[PO
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package com.javaeye.common.util; 8:A6Ew&\]O
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import java.util.List; 2?7a\s
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publicclass PaginationSupport { aI8K*D )@
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publicfinalstaticint PAGESIZE = 30; J_mpI.^Bsf
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privateint pageSize = PAGESIZE; ffyKAZ{]po
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privateList items; Zt[1RMO
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privateint totalCount; gasl%&
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privateint[] indexes = newint[0]; \*w*Q(&3
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privateint startIndex = 0;
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public PaginationSupport(List items, int Hw/1~O$T
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totalCount){ `}u~nu<
setPageSize(PAGESIZE); (#.)~poZ
setTotalCount(totalCount); nmN6RGx
setItems(items); vexQP}N0
setStartIndex(0); Hp":r%)
} T ~t%3G
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public PaginationSupport(List items, int o*QhoDjc
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totalCount, int startIndex){ zn3i2MWS
setPageSize(PAGESIZE); [w~1e)D
setTotalCount(totalCount); e:.Xs
setItems(items); ^IM;D)X&:
setStartIndex(startIndex); I#f<YbzD
} \Jv6Igu
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public PaginationSupport(List items, int =N
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totalCount, int pageSize, int startIndex){ v *~ yN*
setPageSize(pageSize); W#0pFofXw
setTotalCount(totalCount); <OW` )0UX
setItems(items); n4CzReG
setStartIndex(startIndex); 7z6y n=B
} /gHRJ$2|Sx
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publicList getItems(){ eGLLh_V"
return items; f.'o4HSj
} ./ib{ @A.
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publicvoid setItems(List items){ Qo{^jDe,c*
this.items = items; W?/7PVGv5h
} AC(}cMM+
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publicint getPageSize(){ 4- 6'
return pageSize; )r1Z}X(#d
} +2W#=G
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publicvoid setPageSize(int pageSize){ R{6.O+j`
this.pageSize = pageSize; Tj*zlb4
} -D.6@@%Kc}
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publicint getTotalCount(){ #ZGWU_l}
return totalCount; TiF$',WMv
} :d!.E$S
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publicvoid setTotalCount(int totalCount){ FAU^(]-5m
if(totalCount > 0){ ;Z.}~d6>!
this.totalCount = totalCount; F+L q
int count = totalCount / g >-iBxml
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pageSize; z6FG^
if(totalCount % pageSize > 0) o~^hsm[44J
count++; D@4hQC\
indexes = newint[count]; A"z')
for(int i = 0; i < count; i++){ P RX:*0
indexes = pageSize * <6n(a)L1
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}
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}else{ =UNzjmP503
this.totalCount = 0; wTIOCj
} /2?GRwU~P
} w},k~5U^s
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publicint[] getIndexes(){ eVbHPu4
return indexes; c+|,2e
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} %qfEFhRC
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publicvoid setIndexes(int[] indexes){ R0\E?9P
this.indexes = indexes; Yw+_( 2
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} ;U}lh~e11
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publicint getStartIndex(){ )Cyrs~
return startIndex; }QG6KJh_%
} U4zyhj
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publicvoid setStartIndex(int startIndex){ eyl+D sK
if(totalCount <= 0) ga~rllm;i
this.startIndex = 0; 0V`0=" rQ
elseif(startIndex >= totalCount) 't^OIil
this.startIndex = indexes Ge[N5N>
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[indexes.length - 1]; |{Z?a^-NJ
elseif(startIndex < 0) PGu6hV{
this.startIndex = 0; 0$/wH#f
else{ Alp9]
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this.startIndex = indexes K}! VY`
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[startIndex / pageSize]; OYNs1yB
} -Vt*(L
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publicint getNextIndex(){ S1;#58
int nextIndex = getStartIndex() + QSEf
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pageSize; U{n
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if(nextIndex >= totalCount) ~ N_\V
return getStartIndex(); D`r:`
else 3@s|tm1
return nextIndex; q}tLOVu1
} xQ7>u-^
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publicint getPreviousIndex(){ !1)lGjMW
int previousIndex = getStartIndex() - Sep}{`u
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pageSize; 3(}HD*{E[@
if(previousIndex < 0) +!dIEt).U
return0; @+:S'mAQC
else ezCsbV;. [
return previousIndex;
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} x>;!`}x
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} VL&E2^*E
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抽象业务类 u0#q)L8
java代码: 2|kx:^D p
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/** eB<R@a|?S
* Created on 2005-7-12 /) MzF6
*/ J/M1#sE
package com.javaeye.common.business; kiZA$:V8
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import java.io.Serializable; RAR"9 N
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import java.util.List; $2
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import org.hibernate.Criteria; 2zh?]if
import org.hibernate.HibernateException; H)G ^ Y1
import org.hibernate.Session; ,cYU
import org.hibernate.criterion.DetachedCriteria; D#1'#di*t
import org.hibernate.criterion.Projections; <<@$0RW
import 8@|+-)t
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org.springframework.orm.hibernate3.HibernateCallback; =Qp~@k=2
import sr
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org.springframework.orm.hibernate3.support.HibernateDaoS ;Q:^|Fw!F
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upport; }.$oZo9J
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import com.javaeye.common.util.PaginationSupport; +kd88Fx
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public abstract class AbstractManager extends 959&I0=g"
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HibernateDaoSupport { G5 Y 8]N
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privateboolean cacheQueries = false; ="P3TP
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privateString queryCacheRegion; cx&jnF#$
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publicvoid setCacheQueries(boolean T""X~+{Z@
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cacheQueries){ q<>LK
this.cacheQueries = cacheQueries; 6K5KZZG
} [kMXr'TyPX
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publicvoid setQueryCacheRegion(String -z-58FLlO
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queryCacheRegion){ bBW(#
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this.queryCacheRegion = d>M&jSCL
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queryCacheRegion; MP-A^QT
} J@=1zL
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publicvoid save(finalObject entity){ /iQ}DbtRb
getHibernateTemplate().save(entity); _~d C>`K
} Y
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publicvoid persist(finalObject entity){ t^)q[g
getHibernateTemplate().save(entity); $h`?l$jC(@
} Yc3r3Jy
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publicvoid update(finalObject entity){ jX$TiG
getHibernateTemplate().update(entity); `^-?yu@
} \_#0Z+pX
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publicvoid delete(finalObject entity){ )**k3u
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getHibernateTemplate().delete(entity); !Ui3}
} JR<#el
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publicObject load(finalClass entity, R|Z $aHQ
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finalSerializable id){ U59uP
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return getHibernateTemplate().load
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(entity, id); WIb\+!
} if9I7@
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publicObject get(finalClass entity, +[V[{n
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finalSerializable id){ zO<EbqNe!
return getHibernateTemplate().get sZ{Kl\1@
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(entity, id); z%Ywjfn'
} 8c\mm 0n
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publicList findAll(finalClass entity){ K 2$mz
return getHibernateTemplate().find("from R XkE"H{
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" + entity.getName()); e,>L&9] ZI
} !s/ij'T
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publicList findByNamedQuery(finalString XtRfzqg?K
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namedQuery){ ez%RWck
return getHibernateTemplate udX4SBq-pC
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().findByNamedQuery(namedQuery); y4$UPLm
} Z`v6DfK}
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publicList findByNamedQuery(finalString query, &ME[H
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finalObject parameter){ 2/RK
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return getHibernateTemplate Z%\9y]zs
dt{|bQLu3
().findByNamedQuery(query, parameter); <~!7? ak
} Pk T&zSQA
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publicList findByNamedQuery(finalString query, i)Vqvb0Q
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finalObject[] parameters){ #dE#w#=r
return getHibernateTemplate J\b,rOI f
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().findByNamedQuery(query, parameters); P.$U6cq
} lSC3m=4g
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publicList find(finalString query){ UTc$zc7
return getHibernateTemplate().find ca*USM
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(query); L.$9ernVY
} MI0'ou8l
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publicList find(finalString query, finalObject u{"o*udU
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parameter){ N*$<Kjw
return getHibernateTemplate().find x~!B.4gT2
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(query, parameter); V:9| 9$G
} J4 .C"v0a
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public PaginationSupport findPageByCriteria ~;_]U[eOL
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(final DetachedCriteria detachedCriteria){ 1GN>,Lb:o
return findPageByCriteria [bUM x
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +2O('}t
} ag]b]K
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public PaginationSupport findPageByCriteria xY(+[T!OF
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(final DetachedCriteria detachedCriteria, finalint 7)O?jc
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startIndex){ 5)'
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return findPageByCriteria x=Qy{eIe
f)H6 nl7r
(detachedCriteria, PaginationSupport.PAGESIZE, ~mOGNf?f
8 Mp2MZ*p
startIndex); -Cd4yWkO
} 8[Cp
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public PaginationSupport findPageByCriteria ^_9 ^iL
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(final DetachedCriteria detachedCriteria, finalint NoO>CjeFb
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pageSize, T#6'] D
finalint startIndex){ q#LwM]<.@>
return(PaginationSupport) t1b$,jHmKl
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getHibernateTemplate().execute(new HibernateCallback(){ v:B_%-GfOA
publicObject doInHibernate lyI
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(Session session)throws HibernateException { v]F q}I"
Criteria criteria = N~{0QewMI'
+ L;[-]E8
detachedCriteria.getExecutableCriteria(session); D%(9ot{!e
int totalCount = Dx$74~2e
z}.!q{Q
((Integer) criteria.setProjection(Projections.rowCount #pBAGm3
@g9j+DcU
()).uniqueResult()).intValue(); #bUWF|zfT
criteria.setProjection ZLyJ
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(null); OMd{rH
List items = N[^%|
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criteria.setFirstResult(startIndex).setMaxResults d8<Lk9H9R
bv;&oc:r
(pageSize).list(); 6#T?g7\pyR
PaginationSupport ps = RKdf1C
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new PaginationSupport(items, totalCount, pageSize, 1)/B V{n
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startIndex); )wP0U{7?v
return ps; }r]WB)_w
} {k1s@KXtd
}, true); @I\Z2-J
} :{h,0w'd
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public List findAllByCriteria(final J9)wt ?%j
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DetachedCriteria detachedCriteria){ M$1+,[^f
return(List) getHibernateTemplate }U7>_b2
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().execute(new HibernateCallback(){ ItDe_|!L
publicObject doInHibernate 583ej2HPg
#jd?ocoY
(Session session)throws HibernateException { 6T< ~mn
Criteria criteria = @pQv}%
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detachedCriteria.getExecutableCriteria(session); daWmF
return criteria.list(); >4ebvM
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} '97)c7E
}, true); LnZ*,>1Z
} ' :g8a=L
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public int getCountByCriteria(final mvVVPf9
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DetachedCriteria detachedCriteria){ 7
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Integer count = (Integer) [4
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getHibernateTemplate().execute(new HibernateCallback(){ `PSr64h:D
publicObject doInHibernate Y((z9-`
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(Session session)throws HibernateException { E?y0UD[8J
Criteria criteria = NhCO C
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detachedCriteria.getExecutableCriteria(session); kOVx]=
return K).X=2gjY
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criteria.setProjection(Projections.rowCount \@pl:Os
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()).uniqueResult(); Xa*52Q`_
} lcJ`OLG
}, true); ll1?I8}5|
return count.intValue(); ?8-e@/E#x
}
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用户在web层构造查询条件detachedCriteria,和可选的 rNU,(htS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -ud~'<k
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PaginationSupport的实例ps。 8Qu7x[tK?
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ps.getItems()得到已分页好的结果集 =)Ew6}
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ps.getIndexes()得到分页索引的数组 >gFF>L>
ps.getTotalCount()得到总结果数 oVoTnGNM6
ps.getStartIndex()当前分页索引 TT.EQv5
ps.getNextIndex()下一页索引 zY[6Ia{L
ps.getPreviousIndex()上一页索引 R{!s%K&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 YH':cze
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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 UT+\IzL
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一下代码重构了。 QV{Nq=%]
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我把原本我的做法也提供出来供大家讨论吧: i`2Q;Az_P6
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首先,为了实现分页查询,我封装了一个Page类: Lrq+0dI 65
java代码: VxjHB?)
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/*Created on 2005-4-14*/ "kP.Kx!
package org.flyware.util.page; L2{to f
@#VxjXW^
/** "~]9}KM}3W
* @author Joa Ma-^o<{
* Ug_zyfr
*/ `~@BU
publicclass Page { of+$TKQNpN
k B2+ Tr
/** imply if the page has previous page */ 5? c4aAn
privateboolean hasPrePage; &\0LR?Nh
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/** imply if the page has next page */ UY}lJHp0
privateboolean hasNextPage; WNm,r>6m
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/** the number of every page */ >:OOuf#
privateint everyPage; qf)]!wU9
9!bD|-6y
/** the total page number */ $23="Jcl
privateint totalPage; $|(roC(
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/** the number of current page */ 14oD^`-t
privateint currentPage; M?}2
@Z3b^G[
/** the begin index of the records by the current 6K`frt
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query */ 7t@jj%F
privateint beginIndex; ),M8W15
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/** The default constructor */ NNe'5q9
public Page(){ ReSP)%oW
guwnYS
} }E?s*iP
%A82{
/** construct the page by everyPage /^4)V8D_S
* @param everyPage 4`Fbl]Q
* */ L?al2aopF
public Page(int everyPage){ ~0/=5 dC
this.everyPage = everyPage; ld9zOq
} .YS[Md{
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/** The whole constructor */ s)]|zu0"Ku
public Page(boolean hasPrePage, boolean hasNextPage, 5n(p1OM2q
;yHA.}
s?0r\ cc|:
int everyPage, int totalPage, <&H.pN1_
int currentPage, int beginIndex){ cG"jrQ
this.hasPrePage = hasPrePage; `uzRHbJ`
this.hasNextPage = hasNextPage; kx'6FkZPIr
this.everyPage = everyPage; .@B\&U7
this.totalPage = totalPage; u;=("S{"0
this.currentPage = currentPage; [;|g2\
this.beginIndex = beginIndex; pMX7Rl
} _^SNI ~
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/** Q8\Ks|u]
* @return NiWooFPKJ
* Returns the beginIndex. Yq1 ~"he8
*/ zlSwKd(
publicint getBeginIndex(){ M.|hnGXN
return beginIndex; ;K:.*sAa
} VLQfuh;
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/** w5~<jw%>
* @param beginIndex BJW;A>@Pj
* The beginIndex to set. T \0e8"iZ
*/ k)S7SbQ
publicvoid setBeginIndex(int beginIndex){ !3HMGzt
this.beginIndex = beginIndex; ss,6;wfX
} .bpxSU%X
jriliEz;f
/** `^_.E:f
* @return hKX-]+6"
* Returns the currentPage. m4 4aKqw)
*/ /]+t$K\cBq
publicint getCurrentPage(){ .5ingB3%
return currentPage; (F_#LeJ|
} g00XZ0@
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/** bZtjg
* @param currentPage @x{;a 9y
* The currentPage to set. "]JS,g {m
*/ NINyg"g<
publicvoid setCurrentPage(int currentPage){ I}?fy\1A&
this.currentPage = currentPage; -Tz/ZOJ
} (U|W=@8`
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/** -.z~u/uL
* @return `D?vmSQ
* Returns the everyPage. (a)d7y.oo
*/ yYF80mnJz
publicint getEveryPage(){ ;PLby]=O
return everyPage; '9^x"U9c
} e%UFY-2
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/** a&y%|Gs^f
* @param everyPage @$~%C) %u
* The everyPage to set. jfgAI7;b
*/ 4'X^YBm
publicvoid setEveryPage(int everyPage){ q$H'u[KQ06
this.everyPage = everyPage; iLS'47
} *!.'1J:YJ(
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/** L*L3;y|
* @return Lww0 LH
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* Returns the hasNextPage. wcV~z:&^5
*/ m3,]j\
publicboolean getHasNextPage(){ A:;KU
return hasNextPage; u^:!!Suo
} fv`%w
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/** 4'_uN$${$
* @param hasNextPage se(_`a/4Q
* The hasNextPage to set. 4}?Yp e-
*/ A
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publicvoid setHasNextPage(boolean hasNextPage){ !xa,[$w(^
this.hasNextPage = hasNextPage; <L5[#V_
} %JiA,
-
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/** ZM4q@O)/
* @return B23R9.FK
* Returns the hasPrePage. Q*U$i#,
*/ JY%c<
publicboolean getHasPrePage(){ W~ DY-;
return hasPrePage; zXMIDrq
} xJZbax[
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/** \_BaV0<
* @param hasPrePage h4.ZR={E
* The hasPrePage to set. ?M\3n5;
*/ BIX%Bu0'f
publicvoid setHasPrePage(boolean hasPrePage){ )e{~x
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this.hasPrePage = hasPrePage; 6AzH'HF
} uZW1
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/** Ym0Xl(Se
* @return Returns the totalPage. 6K*7%8Y/G
* {) jQbAr(G
*/ tQUp1i{j\
publicint getTotalPage(){ G~YV6??
return totalPage; HH[?LKd<
} yjN|PqtSV
>mh:OJH45
/** T`f9jD
* @param totalPage 7eh}Je8
* The totalPage to set. AA yzT*^
*/ S{J$[!F
publicvoid setTotalPage(int totalPage){ %.<w8ag
this.totalPage = totalPage; aA0aW=R
} VJJw"4DJ
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} hv7!x=?8
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9<-AukK m
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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 kqv>rA3
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个PageUtil,负责对Page对象进行构造: WvNX%se]3
java代码: m", $M>
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/*Created on 2005-4-14*/ f,PFvT$5e
package org.flyware.util.page; L suc*Ps
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import org.apache.commons.logging.Log; 1
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import org.apache.commons.logging.LogFactory; nQg6
j Zf
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/** jskATA
/
* @author Joa J%D'Xlb
* d) G7U$z~
*/ a<c % Xy/
publicclass PageUtil { `^(6{p ?
~])\xC
privatestaticfinal Log logger = LogFactory.getLog Jp_{PR:&
{"'W!WTb
(PageUtil.class); RH>b,
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/** S 8h/AW6l
* Use the origin page to create a new page Q|+m)A4@
* @param page lHz:Iibt
* @param totalRecords }=7tGqfw
* @return )"|g&=
*/ Bn47O~
publicstatic Page createPage(Page page, int `%F.]|Y0
[-1Nn}
totalRecords){ I=Ws
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return createPage(page.getEveryPage(), 1 dI
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page.getCurrentPage(), totalRecords); wxr93$v
} }"Y]GH4Y
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/** A3yVT8
* the basic page utils not including exception A$fd6+{
6$@Pk<w
handler rb&^ ei9B
* @param everyPage 6Z|/M6f
* @param currentPage &l{yEWA}g
* @param totalRecords %^gT.DsX-
* @return page %+FM$xyJ
*/ =@V4V} ?
publicstatic Page createPage(int everyPage, int ~SP.&>Q>
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currentPage, int totalRecords){ #y}@FG
everyPage = getEveryPage(everyPage); #C4
currentPage = getCurrentPage(currentPage); 0>VgO{X
int beginIndex = getBeginIndex(everyPage, k`2 K?9\
M_$pqVm
currentPage); D-A#{e _
int totalPage = getTotalPage(everyPage, Hfm4
+z;xl-*[
totalRecords); +6uun
boolean hasNextPage = hasNextPage(currentPage, r/:s2oQ
[$9 sr=3:
totalPage); ,LWM}L
boolean hasPrePage = hasPrePage(currentPage); QRw306
E9%xSMS8@
returnnew Page(hasPrePage, hasNextPage, {Am\%v\
everyPage, totalPage, "op1x to
currentPage, htlsU*x
,N<;!6e
beginIndex); ~ $!eB/6ty
} !);}zW!
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privatestaticint getEveryPage(int everyPage){ t<}'/
)
return everyPage == 0 ? 10 : everyPage; fZxZ):7i
} Nki18ud#
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privatestaticint getCurrentPage(int currentPage){ mcS/-DaN?
return currentPage == 0 ? 1 : currentPage; } +i
ZY\t
} SX/yY
= ?vk n
privatestaticint getBeginIndex(int everyPage, int f1hi\p0q
VH,k EbJ
currentPage){ DU]MMR
return(currentPage - 1) * everyPage; B2WPjhzD
} zZki9P
hH )jX`Ta
privatestaticint getTotalPage(int everyPage, int Q gDjc'
<74q]C
totalRecords){ =@gH$Q_1
int totalPage = 0; ?VS {,"X
wC'KI8-
if(totalRecords % everyPage == 0) 2~ Gcoda
totalPage = totalRecords / everyPage; 8X5;)h
else dGP*bMCT
totalPage = totalRecords / everyPage + 1 ; S)@R4{=e"V
>:Xzv
return totalPage; cJj0`@0f
} @*%Q,$
Y?ZTl762
privatestaticboolean hasPrePage(int currentPage){ ,^:Zf|V
return currentPage == 1 ? false : true; u0w2v+
} }_@cqx:n^
NT= ?@uxD
privatestaticboolean hasNextPage(int currentPage, _
CXKJ]m4
:v1'(A1t
int totalPage){ J U}XSb
return currentPage == totalPage || totalPage == 8Tt2T}
Y
DY~~pi~
0 ? false : true; *z` {$hc
} mK@\6GOMYP
=qCVy:RL4
'[`.&-;
} "*kWM
Vy16Co
qECc[)B
onG,N1`+
(}gF{@sn
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。 dm)V \?b
a%Mbq;
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 K34ca-~
;# {XNq<1
做法如下: [WY
NA-O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 $J=9$.4"
=
fuF]yL%
的信息,和一个结果集List: 7s<v06Wo
java代码: f!xIMIl)+
1PjSa4
zu*0uL
/*Created on 2005-6-13*/ AG/nX?u7)t
package com.adt.bo; w+2:eFi=/
7.8ukAud
import java.util.List; RTH dL
[^1;8Tbk
import org.flyware.util.page.Page; kxThtjgv
Itj|0PGd
/** :*1|ERGoay
* @author Joa [~f%z(vI
*/ g3e\'B'
publicclass Result { , $78\B^
^^3
>R`
private Page page; i.0}qS?
i*9eU*i|H
private List content; o Ep\po1
=QRLKo#_
/** H]}Iw5Z
* The default constructor 8
6?D
*/ eZI&d;i
public Result(){ }P-9\*hlm
super(); wvx
N6
} F 3,hx
Ndx.SOj
/** M\e%GJ0
* The constructor using fields NZi5rXN
* - FA#hUK$
* @param page qB<D'h7
* @param content WTY{sq\'
o
*/ 1,,o_e\nn3
public Result(Page page, List content){ +]`MdOu
this.page = page; _BHb0zeot
this.content = content; p?0 a"5Q
} Lo7R^>
/LPSI^l!m
/** sBZKf8 @/
* @return Returns the content. g9GE0DbT`
*/ ~Jmn?9 3
publicList getContent(){
UZmzk
return content; py
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} &R\
.^3
]Ol@^$8}
/** O'$0K0k3
* @return Returns the page. g2 :^Z==
*/ ^[\F uSL
public Page getPage(){ /_26D0}UuF
return page; Eq~&d.j
} fCO!M1 t
#x':qBv#
/** -.ha\ t0J
* @param content HQQc<7c",
* The content to set. j9x}D;?n
*/ 5c3)p^]g
public void setContent(List content){ C1r]kF
this.content = content; v(h
} E"pq ZP =
\qNj?;B
/** lwQI
9U[O2
* @param page 5a5I+*
c
* The page to set. 2+sNt6B2
*/ KosAc'/ M
publicvoid setPage(Page page){ vT\`0di~
this.page = page; ;w}ZI<ou
} K}&|lCsb
}
\AoM'+
iNd8M V
}yx'U 3
0K@s_C=n#
P]j{JL/g&
2. 编写业务逻辑接口,并实现它(UserManager, M:Xswwq
iN<&
UserManagerImpl) pRPz1J$58
java代码: g[q1P:I@W
D!TS/J1S;u
gSL$silc
/*Created on 2005-7-15*/ :&&Ps4\Sq
package com.adt.service; qyp"q{k0
w# ,:L)
import net.sf.hibernate.HibernateException; >9uDY+70I3
FL/@e$AK
import org.flyware.util.page.Page; 7W5FHZd'
T&w3IKb|}
import com.adt.bo.Result; 4F)z-<-b
.!l#z|/x
/** az?B'|VX
* @author Joa QVb@/
*/ 6EGh8H f
publicinterface UserManager { zw7=:<z=
Z[ZqQ` 7N
public Result listUser(Page page)throws 8e[kE>tS._
`GqS.O}C
HibernateException; 'fy1'^VPAV
;oH%d;H
} u6awcn
z )a8
^]`
]y2(ZTNTs
R1 hb-
]Tx8ImD#)A
java代码: VbKky1a@
mxGa\{D#y
4F??9o8 }
/*Created on 2005-7-15*/ )l\BZndf
package com.adt.service.impl; 1Xu\Tm\Ux
Y3mATw 3Wh
import java.util.List; ~Q0jz/#c
=S|SQz5%w
import net.sf.hibernate.HibernateException; 9fzbR~s
f+Pu t
import org.flyware.util.page.Page; UF|v=|*{#
import org.flyware.util.page.PageUtil; Jc-0.^]E}
r2M._}bF
import com.adt.bo.Result; uG${`4
import com.adt.dao.UserDAO;
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import com.adt.exception.ObjectNotFoundException; IgG@v9'
import com.adt.service.UserManager; n/=&?#m}d
%a{cJ6P
/** w`CGDF\Oo
* @author Joa e7{3:y|]d3
*/ neoT\HV
publicclass UserManagerImpl implements UserManager { 4u"V52
rgRh ySud
private UserDAO userDAO; A+iQH1C0h
U~s&}M\n
/** V`l.F"<L
* @param userDAO The userDAO to set. v,KH2 (N
*/ `Ft.Rwj2:m
publicvoid setUserDAO(UserDAO userDAO){ BYqDC<Fq
this.userDAO = userDAO; qCc'w8A
} 4IG'Tm
<DvpqlT
/* (non-Javadoc) <q~&g
&&+
* @see com.adt.service.UserManager#listUser )67Kd]
BBnj}XP*4
(org.flyware.util.page.Page) 8]YFlW9
*/ "qu%$L
public Result listUser(Page page)throws n,wLk./`
Fm#4;'x5E
HibernateException, ObjectNotFoundException { V2u^sy
int totalRecords = userDAO.getUserCount(); s4@AK48
if(totalRecords == 0) :\4?{,@_h
throw new ObjectNotFoundException V#ZF0a]
zEl@jK,{$
("userNotExist"); (=j]fnH?
page = PageUtil.createPage(page, totalRecords); 8;5 UO,`T
List users = userDAO.getUserByPage(page); ullq}}
returnnew Result(page, users); ";J1$a
} Vv
B%,_\
fM]zD/ g
} >dUnk)7
B;SYO>.W
PxM]3Aoa
u#/Y<1gn
%F3M\)jU
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %A,4vLe~6
9mEC|(m*WK
询,接下来编写UserDAO的代码: }mxy6m ,
3. UserDAO 和 UserDAOImpl: 17a'C
java代码: CKNC"Y*X
)|x)KY
&y;('w
/*Created on 2005-7-15*/ Zoh2m`6
package com.adt.dao; Be68 Fu0
RnE=T/VZJ
import java.util.List; ReE6h\j
+`r;3kH ..
import org.flyware.util.page.Page; |O%`-2p]p
</>;PnzE
import net.sf.hibernate.HibernateException; V&-pgxf;
l`:M/z6"
/** "]f0wLzh
* @author Joa l5b?
'L
*/ iN %kF'&9
publicinterface UserDAO extends BaseDAO { ~gNa<tg"1
)V*Z|,#no
publicList getUserByName(String name)throws ULIbVy7Y
O3bo3Cm$
HibernateException; c_s=>z
X|{TwmHd
publicint getUserCount()throws HibernateException; uCB7(<
s(w6Ldi
publicList getUserByPage(Page page)throws 8`EzvEm
$VvL
HibernateException; *[]7l]XK.
<S:SIaf0
} 'JsP9>)
:EJ+#
>)YaWcI
*)gbKXb
p~Fc*g[!
java代码: ;?"]S/16,
ycg5S rg
ow,I|A
/*Created on 2005-7-15*/ h2#G
package com.adt.dao.impl; \{ r%.G
#eD@sEn
import java.util.List; `f,SY
Ob$|IH8.
import org.flyware.util.page.Page; ftw\oGrS
(]n^_G#-$
import net.sf.hibernate.HibernateException; 8_US.52V
import net.sf.hibernate.Query; dE=4tqv-r
H4ml0SS^
import com.adt.dao.UserDAO; 9XImgeAs
v}XMFC !
/** )mT{w9u
* @author Joa
UIc )]k%
*/ 2 1.;lj
public class UserDAOImpl extends BaseDAOHibernateImpl y#!8S{
HP}d`C5<R
implements UserDAO { Nih8(pbe
;HtHN
K(o
/* (non-Javadoc) jc)[5i0
* @see com.adt.dao.UserDAO#getUserByName rH"&
$TyV<
G
(java.lang.String) S
'S|k7Lp
*/ ?B3
publicList getUserByName(String name)throws `?+lM
(%=[J/F/
HibernateException { oswS<t{Z
String querySentence = "FROM user in class I?}YS-2
0"]N9N;/
com.adt.po.User WHERE user.name=:name"; ;^za/h>r
Query query = getSession().createQuery M >#kfSF+
X-%XZDB6
(querySentence); e~w-v"'
query.setParameter("name", name); 7SO i9JU_
return query.list(); r9G}[#DO
} MA0}BJoW
o,dO.isgh>
/* (non-Javadoc) Bj5_=oo+d
* @see com.adt.dao.UserDAO#getUserCount() Y -%g5
*/ V+j58Wuf
publicint getUserCount()throws HibernateException { s{\USD6
int count = 0; bBA
#o\[
String querySentence = "SELECT count(*) FROM eT* )r~
@}k5rcQ*/
user in class com.adt.po.User"; MA1.I4dm
Query query = getSession().createQuery &~Qi+b0!
5]D"y Ay81
(querySentence); (!`TO{ !6P
count = ((Integer)query.iterate().next j#mo Vq
N]f"+
()).intValue(); N=R|s$,Oy9
return count; :!H]gC
4
} 3m:[o`L
}{/3yXk[G
/* (non-Javadoc) ;LSdY}*%0
* @see com.adt.dao.UserDAO#getUserByPage R+
#(\
{+r0Nikx_
(org.flyware.util.page.Page) ?hu}wl)
*/ *\ZK(/V
publicList getUserByPage(Page page)throws xV@/z5Tq
R3=PV{`M
HibernateException { S?TyC";!
String querySentence = "FROM user in class (|H1zO
Qz6Ry\u
com.adt.po.User"; Ni"n_Yun
Query query = getSession().createQuery Dg(882#_
>S/m(98
(querySentence); ?[{_*qh
query.setFirstResult(page.getBeginIndex()) vZ3/t8$*
.setMaxResults(page.getEveryPage()); yU'Fyul
return query.list(); >Wvb!8N
} 91Bl{
w;f$oT
} e
lj] e
hn]><kaA
DMO8~5
NbG`v@yH
$]O;D~
至此,一个完整的分页程序完成。前台的只需要调用 }&|S8:
QfqosoP\D
userManager.listUser(page)即可得到一个Page对象和结果集对象 {oQ.y
-:Up$6PR
的综合体,而传入的参数page对象则可以由前台传入,如果用 "\0&1C(G
h:%L% Y9z
webwork,甚至可以直接在配置文件中指定。 Y)="of
U8Rko)
下面给出一个webwork调用示例: }s i{
java代码: &,~0*&r0
<*I%U]
?}<4LK]
/*Created on 2005-6-17*/ HjG!pO{
package com.adt.action.user; l!UF`C0g
\Nd8,hE
import java.util.List; CF"u8yE
+JQ/DNv
import org.apache.commons.logging.Log; 24;F~y8H
import org.apache.commons.logging.LogFactory; ]!l]^/.
import org.flyware.util.page.Page; 9&(d2
H$GJpXIb
import com.adt.bo.Result; -U'3kaX5<
import com.adt.service.UserService; :f1Q0klwP
import com.opensymphony.xwork.Action; W !.F\H,(
v8=7
/** ,D#ssxV
* @author Joa ig:E`Fe@
*/ X'BFR]cm
publicclass ListUser implementsAction{ ca~nfo
@nIoYT='
privatestaticfinal Log logger = LogFactory.getLog T.m*LM
'#JC 6#X
(ListUser.class); MA9Oi(L)K
9k5$rK`
private UserService userService; "zpc)'$L=
.v<Q-P\8/
private Page page; =2-!ay:
wLX:~]<xl
privateList users; ^Yu<fFn
_G9vsi
/* k;aV4
0N9
* (non-Javadoc) ++b1VBP
* +-8S,Rg@
* @see com.opensymphony.xwork.Action#execute() b=Rw=K.
*/ !{hC99q6
publicString execute()throwsException{ ~CTe5PX c
Result result = userService.listUser(page); zB,Vi-)vH
page = result.getPage(); iIZDtZFF
users = result.getContent(); O+ ].'
return SUCCESS; Pr|:nJs
} oaxCcB=\
CJ'pZ]\G
/** 53vnON#{*
* @return Returns the page. POZ5W)F(
*/ W ='c+3O6
public Page getPage(){
;S,k
U{F
return page; {& Pk$Q!
} #ZFedK0vv
55aJ=T
/** ey icMy`7{
* @return Returns the users. 5G$sP,n
*/ QOb+6qy:3
publicList getUsers(){ TgFj-"L\
return users; {\HEUIa]w
} bLSZZfq
w4 R!aWLd
/** CC8M1iW3
* @param page Nd5G-eYI
* The page to set. rUg<(/c
*/ nDiy[Y-4Wp
publicvoid setPage(Page page){ w]<a$C8*y:
this.page = page;
OHEl.p]|
} pi/Jto25z
6p;G~,bd~
/** ar+ j`QIe
* @param users 8xAxn+;
* The users to set. |:yWDZg[
*/ &Nzq/~uqP
publicvoid setUsers(List users){ NI^=cN,l
this.users = users; |@Cx%aEKU
} rGNYu\\
%
~!A,
/** 2h_XfY'3pX
* @param userService g>L4N.ZH_v
* The userService to set. YU*u!
*/ QL_vWG-
publicvoid setUserService(UserService userService){ LIm{Y`XU
this.userService = userService; <FaF67[Q
} 8XS_I{}?
} HUP~
H%`$@U>
1R}rL#h;=
4Z'/dI`
!c 3c%=W
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, !xqy6%p
NVt612/'7y
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 E ISgc {s
3I}(as{Rp
么只需要: O~wZU Zf
java代码: MKl`9 Y3Ge
CtEpS<*c
TnuNoMD.
<?xml version="1.0"?> !+<OED=qe
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Z}b25)
E:_m6
m
1.0//EN" "http://www.opensymphony.com/xwork/xwork- D'Fj"&LK
qdss(LZ
1.0.dtd"> \3WF-!xe
.el&\Jt
<xwork> ()Tl\
*-.{->#Y
<package name="user" extends="webwork- ||xiKg
=sp5.-r
interceptors"> =hw&2c
#![9QUvcf
<!-- The default interceptor stack name `f|Gw5R
j=q*b Qr
--> t\GoUeH]
<default-interceptor-ref Fj_6jsDb
)U2cS\k'7n
name="myDefaultWebStack"/> H}ie D"T_
%oee x1`=
<action name="listUser" yF [|dB
@k|V4
class="com.adt.action.user.ListUser"> Lm!/iseGv
<param -za+Wa`vH
WLO4P
name="page.everyPage">10</param> ryC7O'j_P
<result iJ-z&=dOe
:kQ%Mj>
name="success">/user/user_list.jsp</result> 5 R*
</action> ?Q?=I,2bP
\#yKCA';
</package> =x &"aF1
2#i*'.
</xwork> y;GwMi$KI
E"/r*C+T
'5f6
M^}|2
+o ;}*
w3<%wN>tE
X2[d15!9
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 p;x3gc;0
5#WyI#YNG
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 F%-KY$%
,f[`C-\Q%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 tCVaRP8eC+
MEI.wJZ
>V,i7v*?
Vm"{m/K0
.='hYe.
我写的一个用于分页的类,用了泛型了,hoho "0V8i%a
m4m,-}KNi
java代码: -(;<Q_'s{"
; *ZiH%q,
n N_Ylw
package com.intokr.util; 9w:F_gr
]lgI Q;r
import java.util.List; W3gBLotdg
Vlf =gP
/** us,~<e0
* 用于分页的类<br> |eu:qn8
* 可以用于传递查询的结果也可以用于传送查询的参数<br> m"|AD/2;(
* o3ZqPk]al
* @version 0.01 e.>>al
* @author cheng Py!
F
*/ Z/*X)mBuB
public class Paginator<E> { LJh^-FQ
privateint count = 0; // 总记录数 Y+ Qm.
privateint p = 1; // 页编号 4k]DktY}.
privateint num = 20; // 每页的记录数 V."qxKsz
privateList<E> results = null; // 结果 qt.Y6s:r_
gP^p7aYwn
/** .S6u{B
* 结果总数 /ygC_,mx
*/ S [=l/3c
publicint getCount(){ T1_qAz+
return count; ssUm1F\
} \Um &
O={
?c1i:
publicvoid setCount(int count){ GEGg
S&SM
this.count = count; Ir4M5OR\
} U 6`E\?d`
+ 2j]
/** [$]Kp9YD
* 本结果所在的页码,从1开始 g-NfZj?
* =
a54
* @return Returns the pageNo. `*ml/% \
*/ hlO,mU
publicint getP(){ U8]BhJr$Q
return p; %gbvX^E?
} Od?b(bE.]
R]xXG0
/** *B0
7-
* if(p<=0) p=1 +]*hzWbe
* vUD>+*D
* @param p ?E|be
)
*/ =K`]$Og}8
publicvoid setP(int p){ #*v:.0%
if(p <= 0) [7+dZL[
p = 1; ,^m;[Dl7
this.p = p; \1H~u,a
} IS[&V&.n
-+H?0XN
/** ?c0@A*:o
* 每页记录数量 QP={b+8
*/ '>aj5tZ>R
publicint getNum(){ vq_v;$9}
return num; cq,8^o&
} <ZwmXD.VD
Rct=vDU
/** zjlo3=FQX[
* if(num<1) num=1 R;3T yn+
*/ T!3_Q/~^r
publicvoid setNum(int num){ `ZLA=oD
if(num < 1) dl;
num = 1; ]*\m@lWu
this.num = num; \|< 5zL
} ]R7zvcu&
t9Y?0O}/
/** >SSRwYIN
* 获得总页数 OO /Pc
*/ kA/V=xO<
publicint getPageNum(){ \66j4?H#
return(count - 1) / num + 1; r_EuLFM A
} \NTNB9>CO
l99{ eD
/** p(`?y:.3
* 获得本页的开始编号,为 (p-1)*num+1 fd&=\~1_$
*/ YjTA+1}
publicint getStart(){ n+94./Mh
return(p - 1) * num + 1; MET"s.v
} G&f~A;'7k
go[(N6hN
/** X{-[
E^X
* @return Returns the results. Vv<Tjr
*/ D8r=Vf
publicList<E> getResults(){ ??g `c=R!V
return results; hrZ=8SrW
} se, 0Rvkt
/4_^'RB
public void setResults(List<E> results){ +:D90p$e
this.results = results; q7-.-k<dQ
} _6/q.
Lr ;PESV
public String toString(){ lMW4SRk1C
StringBuilder buff = new StringBuilder yw{;Qm2\7
C?h`i ^ >2
(); UW@BAj@^@
buff.append("{"); qTd6UKg
buff.append("count:").append(count); ,^d!K(xb
buff.append(",p:").append(p); yG%<LP2p@f
buff.append(",nump:").append(num); W%.ou\GN^t
buff.append(",results:").append %@4/W N
;~
,<8
(results); >~)IsQ*%
buff.append("}"); \8HLQly|@
return buff.toString(); 'V-_3WWxU
} 7Ew.6!s#n1
r1o_i;rg
} I,0Z* rw
= m6yH_`@
1p]Z9$Y