Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )6S}O*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4)S?Y"Bs
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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 ?
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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 x)Om[jZE
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分页支持类: 9MlfZsby
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java代码: WYd,tGz
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package com.javaeye.common.util; ktJLpZ<0O
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import java.util.List; V$%Fs{
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publicclass PaginationSupport { n\NDi22
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publicfinalstaticint PAGESIZE = 30; wAwH8x LU
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privateint pageSize = PAGESIZE; ,#FH8%Yf
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privateList items; bWzc=03
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privateint totalCount; N.cRZm%
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privateint[] indexes = newint[0]; 43]&SXprH
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privateint startIndex = 0; dfd%A"
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public PaginationSupport(List items, int 3W
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totalCount){ AR2+W^aM3
setPageSize(PAGESIZE); +Rd{ ?)2~
setTotalCount(totalCount); [vT,zM
setItems(items); #>oO[uaY
setStartIndex(0); FA GVpO[
} M|u5Vs1
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public PaginationSupport(List items, int )y Y;%
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totalCount, int startIndex){ JFkjpBS
setPageSize(PAGESIZE); Q)dns)_x
setTotalCount(totalCount); ~hX'FV
setItems(items); &^>r<~]
setStartIndex(startIndex); 51usiOq
} D(GHkS*0q
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public PaginationSupport(List items, int hY'%SV
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totalCount, int pageSize, int startIndex){ W%:zvqg
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setPageSize(pageSize); j3F=P
setTotalCount(totalCount); ]d(}b>gR~(
setItems(items); GT0'bge
setStartIndex(startIndex); ?uv%E*TU
} 4\RuJx
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publicList getItems(){ mY9K)]8
return items; #d(r^U#I
} ~;` #{$/C&
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publicvoid setItems(List items){ <GEn9;\
this.items = items; 8tk`1E8!j
} bp_@e0
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publicint getPageSize(){ $r_ gFv
return pageSize; {F[Xe_=#"
} WDR!e2G
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publicvoid setPageSize(int pageSize){ r8$TT\?~
this.pageSize = pageSize; ozG:f*{T
} ]y
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publicint getTotalCount(){ a4YyELXe
return totalCount; $Tza<nA
} nm.d.A/]Z
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publicvoid setTotalCount(int totalCount){
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if(totalCount > 0){ xOlkG*3c
this.totalCount = totalCount; ,5,4 Qf7
int count = totalCount / c#Bde-dh
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pageSize; DFMWgBL
if(totalCount % pageSize > 0) Pe.D[]S
count++; tK*f8X+q
indexes = newint[count]; C'#:}]@E
for(int i = 0; i < count; i++){ ;iVyJZI
indexes = pageSize * xC(PH?_
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} CDhk!O..
}else{ K"61i:F
this.totalCount = 0; .67W\p
} E;N8{Ye_
} ]M/w];:
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publicint[] getIndexes(){ e[n>U@
return indexes;
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} 0ro+FJ r
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publicvoid setIndexes(int[] indexes){ NbdaP{{
this.indexes = indexes; _wMz+<7bY
} ]So%/rOvX
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publicint getStartIndex(){ 6*E7}
return startIndex; |8"HTBb\CW
} '@FKgy;B)-
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publicvoid setStartIndex(int startIndex){ IaB
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if(totalCount <= 0) j,Y=GjfGM
this.startIndex = 0; 1<*-,f
elseif(startIndex >= totalCount) DIY WFVh
this.startIndex = indexes =B\?(
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[indexes.length - 1]; JW$#~"@r
elseif(startIndex < 0) kF?\p`[a
this.startIndex = 0; a)]N#gx
else{ 2&M
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this.startIndex = indexes @S{,g;8
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[startIndex / pageSize]; ev>: 3_ s
} $ _zdjzT
} +ad 2
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publicint getNextIndex(){ [30< 0
int nextIndex = getStartIndex() + +XsY*$O
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pageSize; _\[Zr.y
if(nextIndex >= totalCount) VGSe<6Hh
return getStartIndex(); 9%x[z%06
else =T1i(M#
return nextIndex; m2_B(-
} (+_Amw!W
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publicint getPreviousIndex(){ F](kU#3"S
int previousIndex = getStartIndex() - :Z<-J`
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pageSize; 9khD7v
if(previousIndex < 0) 6 ,k}v:
return0; b.$Gc!g
else ^K3{6}]
return previousIndex; xX}vxhN
} K2&pTA~OR
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} hd\iW7
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抽象业务类 $AoN,B>
java代码: A\WgtM
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/** TzVNZDQ`Jl
* Created on 2005-7-12
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*/ 9v^MZ^Y{
package com.javaeye.common.business; aVd{XVE
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import java.io.Serializable; *Bc=gl$
import java.util.List; I( pU_7mw
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import org.hibernate.Criteria; V+_L9
import org.hibernate.HibernateException; koe&7\ _@
import org.hibernate.Session; "{|9Yis=
import org.hibernate.criterion.DetachedCriteria; +b
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import org.hibernate.criterion.Projections; 'R= r9_%
import <Cm:4)~
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org.springframework.orm.hibernate3.HibernateCallback; &`{%0r[UD#
import ~,.Agx
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org.springframework.orm.hibernate3.support.HibernateDaoS u[y>DPPx
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upport; #|)GarDG
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import com.javaeye.common.util.PaginationSupport; 5{VrzzOK}
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public abstract class AbstractManager extends HX?5O$<<N
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HibernateDaoSupport { !ZHPR:k|
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privateboolean cacheQueries = false; TAIcp*)ZM
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privateString queryCacheRegion; %.[t(F
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publicvoid setCacheQueries(boolean ,@8>=rT
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cacheQueries){ I"y=A7Nq
this.cacheQueries = cacheQueries; 3@_je)s
} K'7i$bl%
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publicvoid setQueryCacheRegion(String (F
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queryCacheRegion){ rV54-K;`0
this.queryCacheRegion = +UB+. 5P
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queryCacheRegion; 0'% R@|
} !zVuO*+
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publicvoid save(finalObject entity){ mN!>BqvN
getHibernateTemplate().save(entity); o
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} `b+f^6SJn
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publicvoid persist(finalObject entity){ 1)X%n)2pr
getHibernateTemplate().save(entity); z
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} Jr==AfxyT
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publicvoid update(finalObject entity){ w%g@X6
getHibernateTemplate().update(entity); S9t_2%e
} X)$3sTj
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publicvoid delete(finalObject entity){ 80x
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getHibernateTemplate().delete(entity); D
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} y9?B vPp+
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publicObject load(finalClass entity, -"UK NB!
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finalSerializable id){ 2kp.Ljt@
return getHibernateTemplate().load 1>[3(o3t
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(entity, id); )0
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} c 5+oP j
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publicObject get(finalClass entity, n{6XtIoYq
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finalSerializable id){ k3da*vwE
return getHibernateTemplate().get zQMsS
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(entity, id); 8$io^n\i
} Ia=wf"JS)
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publicList findAll(finalClass entity){ Xp[[ xV|
return getHibernateTemplate().find("from G|Yw
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}
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publicList findByNamedQuery(finalString 8 P.t
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namedQuery){ >Vy=5)/i
return getHibernateTemplate B.-5$4*s
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().findByNamedQuery(namedQuery); ,%w_E[2
} 2f9~:.NgF
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publicList findByNamedQuery(finalString query, {a.{x+!5I-
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finalObject parameter){ p%EU,:I6
return getHibernateTemplate ^n!{ vHz
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().findByNamedQuery(query, parameter); RIJ+]uir4
} Ir|Q2$W2^c
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publicList findByNamedQuery(finalString query, Wp/!;
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finalObject[] parameters){ S}gUz9ks
return getHibernateTemplate }jBr[S5
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().findByNamedQuery(query, parameters); #Z;ziM:
} zhY VMQ
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publicList find(finalString query){ $6}siU7s4
return getHibernateTemplate().find IzF7W?k
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(query); w~y+Pv@
} 1dh_"/
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publicList find(finalString query, finalObject zuUf:%k}I
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parameter){ e;~[PYeu
return getHibernateTemplate().find 5|f[evQj<S
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(query, parameter); <Z{\3X^
} *q_
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public PaginationSupport findPageByCriteria h.>6>5$n
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(final DetachedCriteria detachedCriteria){ p/>}{Q )Y
return findPageByCriteria <use+C2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); G`!#k!&r
} 2c@4<kyfP
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public PaginationSupport findPageByCriteria V^B'T]s
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(final DetachedCriteria detachedCriteria, finalint <^6|ZgR
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startIndex){ "^VKs_U8o
return findPageByCriteria \_}Y4
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(detachedCriteria, PaginationSupport.PAGESIZE, '
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startIndex); [U@#whE O
} )D_#
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public PaginationSupport findPageByCriteria sYM3&ikyHI
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(final DetachedCriteria detachedCriteria, finalint d]6.$"\"p
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pageSize, ~K]5`(KV
finalint startIndex){ NBZFIFO<
return(PaginationSupport) ?ORG<11a
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getHibernateTemplate().execute(new HibernateCallback(){ ' _Ij9{M
publicObject doInHibernate pE<dK.v6
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(Session session)throws HibernateException { PB00\&6H
Criteria criteria = V`qHNM/t
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detachedCriteria.getExecutableCriteria(session); @T[}]e
int totalCount = SVWtKc<
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((Integer) criteria.setProjection(Projections.rowCount \9TCP;{
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()).uniqueResult()).intValue(); }bIbMEMn
criteria.setProjection g>)&Q>}=W
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(null); O& k+;r
List items = 0mk-o
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criteria.setFirstResult(startIndex).setMaxResults {#"[h1
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(pageSize).list(); $?RxmWsP
PaginationSupport ps = }tue`">h
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new PaginationSupport(items, totalCount, pageSize, EwDFU K
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startIndex); j"o8]UT/
return ps; OXc!^2^
} sbn|D\p
}, true); [~e{58}J|
} KqC8ozup
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public List findAllByCriteria(final ,SQmQ6h
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DetachedCriteria detachedCriteria){ d7
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return(List) getHibernateTemplate ;s{k32e
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().execute(new HibernateCallback(){ Hw[(v[v
publicObject doInHibernate m/}(dT;
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(Session session)throws HibernateException { ?Pg{nlJvq
Criteria criteria = d +0(H
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detachedCriteria.getExecutableCriteria(session); Si=zxy T
return criteria.list(); ,m ^q>
}
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}, true); 8K(3{\J[V
} F?"#1je
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public int getCountByCriteria(final +<qmVW^X
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DetachedCriteria detachedCriteria){ xF|P6GXg
Integer count = (Integer) ['1JNUX
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getHibernateTemplate().execute(new HibernateCallback(){ -<e8\ Z`
publicObject doInHibernate B#Sg:L9Tr'
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(Session session)throws HibernateException { `*?8<Vm
Criteria criteria = }M_Yn0(3
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detachedCriteria.getExecutableCriteria(session); +-8u09-F
return m3o+iYkMD
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criteria.setProjection(Projections.rowCount 4DGc[
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()).uniqueResult(); r7dvj#^
} -TL `nGF
}, true); d:|(l^]{r
return count.intValue(); gie.K1@|
} [}p/pj=
} X0G
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用户在web层构造查询条件detachedCriteria,和可选的 'VH%cz*
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ' pnkm0=`
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PaginationSupport的实例ps。 W
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ps.getItems()得到已分页好的结果集 NhP&sQO
ps.getIndexes()得到分页索引的数组 ry99R|/d1
ps.getTotalCount()得到总结果数 drv"I[}{A
ps.getStartIndex()当前分页索引 oh>X/uj
ps.getNextIndex()下一页索引 kqyVUfX$3
ps.getPreviousIndex()上一页索引 hU3z4|~+
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 fi/[(RBG
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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 =%wwepz6
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一下代码重构了。 lDBn3U&z>
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我把原本我的做法也提供出来供大家讨论吧: C^dnkuA
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首先,为了实现分页查询,我封装了一个Page类: #gHs!b-g@
java代码: #5Zf6w
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/*Created on 2005-4-14*/ ZO^Y9\L
package org.flyware.util.page; jjs1Vj1@<
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/** "q-,140_
* @author Joa aa:97w~s0
* d8Keyi8[
*/ !!WSGZUR
publicclass Page { !3E
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/** imply if the page has previous page */ }w,^]fC:
privateboolean hasPrePage; Pk94O
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/** imply if the page has next page */ `#X\@?'5
privateboolean hasNextPage; p=tj>{
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/** the number of every page */ *1Q~/<W
privateint everyPage; .x
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/** the total page number */ ws{2 0
privateint totalPage; JZCRu_M>|
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/** the number of current page */ h4j{44MT
privateint currentPage; hQm"K~SW=
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/** the begin index of the records by the current "IK QFt'
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query */ m{U+aqAQK
privateint beginIndex; ~AD%aHR
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/** The default constructor */ fvW7a8k3
public Page(){ rv(Qz|K@
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} *AO^oBeY
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/** construct the page by everyPage ;8Z\bHQ>
* @param everyPage l.DC20bs
* */ 1>JUI5 {
public Page(int everyPage){ ^Fy{Q*p`(
this.everyPage = everyPage; PMDx5-{A/t
} [V\0P,l
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/** The whole constructor */ LuM[*_8
public Page(boolean hasPrePage, boolean hasNextPage, RHV&m()Q
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int everyPage, int totalPage, 6K/j,e>L
int currentPage, int beginIndex){ p Rt=5WZ
this.hasPrePage = hasPrePage; dS7?[[pg9
this.hasNextPage = hasNextPage; %p5%Fs`sd
this.everyPage = everyPage; `@8QQB
this.totalPage = totalPage; TFX*kk&R
this.currentPage = currentPage; ]fN\LY6p
this.beginIndex = beginIndex; L-7?:
} !n<vN@V*3d
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/** /cPezX
* @return ;~&F}!pQ
* Returns the beginIndex. [4V{~`sF
*/ W'Wr8~{h
publicint getBeginIndex(){ fc'NU(70c
return beginIndex; NaeG2>1
} kaSy 9Y{
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/** z(sfX}%
* @param beginIndex k"*A@
* The beginIndex to set. ZzU3j ^
*/ \,YF['Qq
publicvoid setBeginIndex(int beginIndex){ +,` Cv_O
this.beginIndex = beginIndex; by 'P}
} FLT4:B7
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/** d5/x2!mH8
* @return ),9^hJ1+@
* Returns the currentPage. (vX+
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*/ Ks|qJ3;
publicint getCurrentPage(){ Eiqx1ZM
return currentPage; QnsD,F; /
} (*{Y#XD{
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/** vrr&Ve
* @param currentPage )bJS*#
* The currentPage to set. MeD}S@H
*/ vM_UF{a$=
publicvoid setCurrentPage(int currentPage){ :#CQQ*@
this.currentPage = currentPage;
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} W4
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/** gIGyY7{(s8
* @return XH9Y|FX%#
* Returns the everyPage. 6Fp}U
*/ @'go?E)f
publicint getEveryPage(){ ulY8$jB
return everyPage; IM""s]
} 74Fv9
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/** ^[]q/v'3m!
* @param everyPage #$vQT}
* The everyPage to set. k!9LJ%Xh
*/ BSe{HmDq
publicvoid setEveryPage(int everyPage){ PtfxF]%H
this.everyPage = everyPage; t0^chlJP$
} (jR7D"I
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/** 0?x9.]
* @return kU*Fif
* Returns the hasNextPage. <4l;I*:2&
*/ = JE4C9$,
publicboolean getHasNextPage(){ lCyBdY9n
return hasNextPage; jv8diQ.
} @-^jbmu^
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/** 75>)1H)Xm
* @param hasNextPage w.AF7.X`1
* The hasNextPage to set. puv/+!q
*/ w$E8R[J~P
publicvoid setHasNextPage(boolean hasNextPage){ l"T{!Oq
this.hasNextPage = hasNextPage; rMV<}C ^
} k15fy"+Ut
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/** WUEjWJA-MB
* @return .ty^ k@J|]
* Returns the hasPrePage. pwu8LQ3b{O
*/ d9@Pze">e
publicboolean getHasPrePage(){ *hm;C+<~
return hasPrePage; :6N'%LKK
} >q+q];=(
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/** 0j'H5>m"
* @param hasPrePage ( E8(np
* The hasPrePage to set. '[T#d! T
*/ S2^Ckg
publicvoid setHasPrePage(boolean hasPrePage){ oB BL7/L
this.hasPrePage = hasPrePage; @Czj] t`
} -Hx._I$l
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/** P&6hk6#
* @return Returns the totalPage. [@"7qKd1
* Xa=M{x
*/ L`iC?<}
publicint getTotalPage(){ >TnV
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return totalPage; H#Aar
} x)^/3
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/** %-A #7\
* @param totalPage =Wgz\uGJ
* The totalPage to set. T+$Af,~
*/ ``Yw-|&:Ae
publicvoid setTotalPage(int totalPage){ \[!k`6#t7
this.totalPage = totalPage; mbZS J
} h 8ND=(
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} +!'rwD
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=}8:zO
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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
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个PageUtil,负责对Page对象进行构造: 8M"0o}wx
java代码: xe=/T#%
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/*Created on 2005-4-14*/ C2Pw;iK_t
package org.flyware.util.page; X}-)io
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import org.apache.commons.logging.Log; R cz;|h8
import org.apache.commons.logging.LogFactory; 9q4%s?)j
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/** O%Mi`\W@
* @author Joa |3h-F5V)
* 8}Qmhm`_j=
*/ "IvFkS=*Q
publicclass PageUtil { /W vgC)
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privatestaticfinal Log logger = LogFactory.getLog RTEzcJ>
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(PageUtil.class); =Eh~ wm
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/** )PU_'n=>
* Use the origin page to create a new page [Ju5O[o
* @param page `L. kyL
* @param totalRecords `u *:wJsv
* @return Q`ALyp,9b
*/ $4&%<'l3I
publicstatic Page createPage(Page page, int 5V{>
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totalRecords){ Y[8GoqE|
return createPage(page.getEveryPage(), SGp}(j>
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page.getCurrentPage(), totalRecords); Hl3%+f
} : }q~<
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/** q\`0'Z,
* the basic page utils not including exception &azy1.i~
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handler ~h<<-c
* @param everyPage n@`:"j%s_
* @param currentPage gZ^'hW-{
* @param totalRecords 9S y |:J0
* @return page - fB;pS,
*/ `L=d72:
publicstatic Page createPage(int everyPage, int z"vI-~,YU
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currentPage, int totalRecords){ UrP jZ:K'
everyPage = getEveryPage(everyPage); 4dgo*9
currentPage = getCurrentPage(currentPage); &Oxf^x["]
int beginIndex = getBeginIndex(everyPage, /4!.G#DLQ
&6#>a"?"
currentPage); JJ+A+sfdk
int totalPage = getTotalPage(everyPage, eL` }j9
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totalRecords); I\,m6=q
boolean hasNextPage = hasNextPage(currentPage, ]nM 2J}7
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totalPage); 3R=R k
boolean hasPrePage = hasPrePage(currentPage); I8s%wY9
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returnnew Page(hasPrePage, hasNextPage, {j!jm5
everyPage, totalPage, e-`=?tct
currentPage, TB@0j
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beginIndex); 0&@pD`K e
} u |EECjJn
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privatestaticint getEveryPage(int everyPage){ W7
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return everyPage == 0 ? 10 : everyPage; .GM}3(1fX`
} iem@K
6iZ:0y0t+6
privatestaticint getCurrentPage(int currentPage){ p3L0'rY|+
return currentPage == 0 ? 1 : currentPage; O7x'q<PFU
} 3SMb#ce*o
VGPBD-6)
privatestaticint getBeginIndex(int everyPage, int M;$LB@h
S
Y7'S#
currentPage){ Z6F^p8O-
return(currentPage - 1) * everyPage; ="<S1}.
} N;6@f*3_i
c@ea
;Cv
privatestaticint getTotalPage(int everyPage, int
YO3$I!(
Jy?#@/~
totalRecords){ KVC$o+<'`%
int totalPage = 0; f]*_]J/
>,#73u#
if(totalRecords % everyPage == 0) Tam\,j
totalPage = totalRecords / everyPage; KkF3E*q\H
else `Qrrnq
totalPage = totalRecords / everyPage + 1 ; MUeS8:q-N
G9_M~N%a
return totalPage; |fd}B5!c
} :/1/i&a
.0eHP
privatestaticboolean hasPrePage(int currentPage){ fK'qc L
return currentPage == 1 ? false : true; F:P&hK
} 9tt0_*UX
\!_:<"nX.
privatestaticboolean hasNextPage(int currentPage, =q4QBAW
:q+D`s
int totalPage){ !:7aXT*D$
return currentPage == totalPage || totalPage == R\+O.vX
5ZPe=SQ{
0 ? false : true; x,3oa_'E
} GkutS.2G#
>h+G$&8[y
R8uiLZd
} T&5dF9a
N-+`[8@(P<
fV`R7m.
B 3Yj
1aAYBV<3
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }: W6Bo-|
aJ"Tt>Y[.~
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 'za4c4b*u
Hsoe?kUHF
做法如下: 'x-PQQ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1Xv- e8M
HKr6h?Si^
的信息,和一个结果集List: 9%VNzPzf
java代码: ,B,2t u2
+QqEUf<U*,
I&}Md73
/*Created on 2005-6-13*/ 4~G++|NQ
package com.adt.bo; 05<MsxB"w
nsq7,%5
import java.util.List; W .c:Pulg
\\qw"w9
import org.flyware.util.page.Page; TT(dCHft
8^H <dR
/** d45JT?qg&
* @author Joa ya9V+/i7T_
*/ >D';i\2j&
publicclass Result { Ef;OrE""
=9oN#4mWK
private Page page; C#5z!z/:%
YdgaZJs
private List content; S*o%#ZJN
(+Yerc.NQt
/** |WiK*
* The default constructor T/%s7!E
*/ w*})ZYIUT
public Result(){ X9f!F2x
super();
*Mt's[8
}
\|Qx`-
0ih=<@1 K
/** +fd^$Qd%K
* The constructor using fields 29?{QJb
* F3\' WQh
* @param page mis
cmD
* @param content fjUyx:
*/ :N~1fvx
public Result(Page page, List content){ bBkF,`/f$
this.page = page; '3f"#fF6
this.content = content; (Ck|RojC
} ;}b.gpG
s@sr.'yU
/** b!Q|0X.?
* @return Returns the content. M@rknq@
*/ ic:_v?k
publicList getContent(){ V`V
Z[
return content; .kSx>3
} ?Sj3-*/?
-X ~VXeg
/** 1&~u:RUXe
* @return Returns the page. zg!;g`Z@S
*/ >!|Hns
public Page getPage(){ !5Ko^: +Y
return page; !HM|~G7
} }g:y!pk
gaaW:* *y
/** +A 6xY
* @param content `1F[.DdF
* The content to set. s+>VqyHgf
*/ , ;L
public void setContent(List content){ =j]us?5
this.content = content; [Y_6PR
} ^w.x~#zI
{O,D9 <
/** jk2h"):B>
* @param page [?mDTD8zU
* The page to set. @~0kSA7
*/ nS0K&MH6B
publicvoid setPage(Page page){ ;aKdRhDo
this.page = page; [#>ji+%=
} o0b}:`
} jW5n^Y)
]q DhGt
3!M;Z7qF]
%"~\Pu*>
+U9Gj#
2. 编写业务逻辑接口,并实现它(UserManager, GUJ[2/V~A
&K5wCNX1
UserManagerImpl) lwhAF, '$
java代码: 2mAXBqdm
vh3Xd\N
/gZrnd?
/*Created on 2005-7-15*/ pIdJ+gu(s
package com.adt.service; (.a:jL$
qepsR/0M
import net.sf.hibernate.HibernateException; ',k0_n?t
m`!C|?hu
import org.flyware.util.page.Page; 2'_xg~
=s`\W7/;{-
import com.adt.bo.Result; R,CFU l7Q
;
mF-y,E
/** Dk4Jg++
* @author Joa S0nBX"$u
*/ }Z*@EWc>
publicinterface UserManager { U.<';fKnT
<@xp. Y
public Result listUser(Page page)throws l-4T Tg
{s!DRc]ln
HibernateException; Xk%92Pto
|
Zx
} 1lZl10M:f
Ub=g<MYHV
;rWgt!l
mDz{8N9<FG
v'0A$`w`
java代码: }N^.4HOS8
z><=F,W
#UL:#pY
/*Created on 2005-7-15*/ XL>v$7`#
package com.adt.service.impl; ;Ut0tm
@ qWgokf
import java.util.List; Lbk?( TL
,R/HT@
import net.sf.hibernate.HibernateException; ]2\|<.
'EoJo9p6}
import org.flyware.util.page.Page; YL\d2
import org.flyware.util.page.PageUtil; aOWW..|
(&R/ns~
import com.adt.bo.Result; d:*,HzG
import com.adt.dao.UserDAO; ]b!o(5m
import com.adt.exception.ObjectNotFoundException; $j*%}x~[
import com.adt.service.UserManager; >2tQ')%DJ
O@r%G0Jge
/** Zyxr#:Qm
* @author Joa U 2am1}
*/ x`K<z
J
publicclass UserManagerImpl implements UserManager { $Kgw6
$,$bZV
private UserDAO userDAO; KM$Lu2
zhtNL_
/** mn;;wp
* @param userDAO The userDAO to set. =W'a6)WE
*/ |Qo`K%8
publicvoid setUserDAO(UserDAO userDAO){ Zg1=g_xY
this.userDAO = userDAO; |}s)Wo
} @\0U`*]^)
rOd<nP^`\
/* (non-Javadoc) 734)s
* @see com.adt.service.UserManager#listUser tE3#Uq
Bfe#,
(org.flyware.util.page.Page) c,nE@~ul2
*/ )90 Q
public Result listUser(Page page)throws tY~gn|M
A+P9M \u.
HibernateException, ObjectNotFoundException { x`n$4a'7b
int totalRecords = userDAO.getUserCount(); |#9Nu9ak
if(totalRecords == 0) -xs@rV`
throw new ObjectNotFoundException {FRUB(68b
}jHS
("userNotExist"); qv\n]M_&
page = PageUtil.createPage(page, totalRecords); Iz Vb
List users = userDAO.getUserByPage(page); Q@]~O-
returnnew Result(page, users); pQv`fr=
} w#|uR^~
~q]@Jp
} 2;h4$^`dt
)e&U'Fx
q.sErr[zc
.Z%y16)T
N{oi }i6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 UrtA]pc3L
7<FI[
询,接下来编写UserDAO的代码: Jw13
Wb-
3. UserDAO 和 UserDAOImpl: j9Qd
45
java代码: Bgb~ Tz'
%siBCjvo=
L#U-dzy\
/*Created on 2005-7-15*/ {A!1s;
package com.adt.dao; Jr|"QRC
^`M,ju
import java.util.List; >s0A.7,5
\S#Mc
import org.flyware.util.page.Page; E"i<fr
T
."`mh&+`
import net.sf.hibernate.HibernateException; Pw c)u&
gbvM2
/** 0,a/t
jSr
* @author Joa Qm9r>m6p@N
*/ %3p~5jhm1
publicinterface UserDAO extends BaseDAO { 2ed4xhV
_8zZ.~)
publicList getUserByName(String name)throws Q\H1=8
ng,64(wOY
HibernateException; \iN3/J4
87&BF)]
publicint getUserCount()throws HibernateException; wY$'KmNW
!+bLhW`
publicList getUserByPage(Page page)throws Cn\5Vyrl
D1xIRyc/
HibernateException; ~vL7$-:
Tt^PiaS!
} }uZtAH|
vI84=n
sY|by\-c
+-%&,>R
~Qg:_ @@\
java代码: "6^~-`O
*U<l$gajq
oc|%|pmRd<
/*Created on 2005-7-15*/ 4O I''i
package com.adt.dao.impl; l g0 'qH8
m=m T`EP
import java.util.List; Ca2He}r`
v d{`*|x
import org.flyware.util.page.Page; &XvSAw+D@
MC'2;,
import net.sf.hibernate.HibernateException; 0fOx&"UAB
import net.sf.hibernate.Query; 1\t# *N
0c-.h
import com.adt.dao.UserDAO; 8D
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yuef84~
/** HpXQD;
* @author Joa MbT;]Bo
*/ rd
)_*{
public class UserDAOImpl extends BaseDAOHibernateImpl :m&cm%W]ts
vk1E!T9X
implements UserDAO { "e-RV
13JZ\`ceb
/* (non-Javadoc) $.5f-vQp
* @see com.adt.dao.UserDAO#getUserByName ',_E;(
Y^Y1re+}
(java.lang.String) hx.ln6=4
*/ mm1fG4
*%
publicList getUserByName(String name)throws uY_vX\;67z
?'8(']/
HibernateException { 7Rq|N$y.3
String querySentence = "FROM user in class
t@#l0lu$
:lfUVa{HN
com.adt.po.User WHERE user.name=:name"; S-
N
[
Query query = getSession().createQuery !
^ DQX=1
f,
iHM
(querySentence); xwJ.cy
query.setParameter("name", name); <Pnz$nH:e
return query.list(); m>:zwz< ;
} fep8hf B;
T?4I\SG
/* (non-Javadoc) 0XzrzT"&
* @see com.adt.dao.UserDAO#getUserCount() K2o\+t
*/ c $fYK
publicint getUserCount()throws HibernateException { j*fs [4
int count = 0; N?3BzI%?
String querySentence = "SELECT count(*) FROM dRGgiQO
K;'s+ZD
user in class com.adt.po.User"; +oRBSAg -
Query query = getSession().createQuery DX b=Ku
xgQ&'&7l
(querySentence); uLq%Nu
count = ((Integer)query.iterate().next R^f-j-$o]
ls ,;ozU
()).intValue(); T*"*##c
return count; [B1h0IR
} Z1Pdnc7S[
EG#mNpxE
/* (non-Javadoc) +#RqQ8\
* @see com.adt.dao.UserDAO#getUserByPage VSDG_:!K
tPz!C&.=
(org.flyware.util.page.Page) ]m=2 $mK
*/ ]b&O#D9
publicList getUserByPage(Page page)throws +\s&v!
lBZhg~{
HibernateException { Ch0t'
String querySentence = "FROM user in class V+>.Gf
_!C M
com.adt.po.User"; \2OjIEQQ
Query query = getSession().createQuery 2 e9lk$
vD91t/_+
(querySentence); Y q(CD!
query.setFirstResult(page.getBeginIndex()) S7kZpD$
.setMaxResults(page.getEveryPage()); f2,\B6+
return query.list(); w(cl,W/w
} *Hed^[sO
+sm9H"_0
} >`)IdX
yr[HuwU
%Q. |qyq
.?dYY;P
<E1ngG
至此,一个完整的分页程序完成。前台的只需要调用 @mm~i~~KA
f~Ve7
userManager.listUser(page)即可得到一个Page对象和结果集对象 7 P/1'f3
Y<)9TU:D!
的综合体,而传入的参数page对象则可以由前台传入,如果用 "3e1 7dsY
4VI'd|Ed
webwork,甚至可以直接在配置文件中指定。 -esq]c%3
o?((FW5.;
下面给出一个webwork调用示例: up
)JU [
java代码: oBI@.&tG}
^hyp}WN
Wo,"$Z6B
/*Created on 2005-6-17*/ 'E_~>
package com.adt.action.user; 2/f!{lz ](
!v?WyGbUg
import java.util.List; P{[@t_
6[S-%|f
import org.apache.commons.logging.Log; dW} m44X
import org.apache.commons.logging.LogFactory; &A)u!l Ue
import org.flyware.util.page.Page; 54>gr1B
AB[#
import com.adt.bo.Result; 7CV}QV}G
import com.adt.service.UserService; [*W l=
import com.opensymphony.xwork.Action; |N%#;7
Mcm%G#
/** TV[@!E a
* @author Joa u[+/WFH
*/ 1#
;`1i
publicclass ListUser implementsAction{ ;^9y#muk
]^BgSC
privatestaticfinal Log logger = LogFactory.getLog "e@?^J)
1b`WzoJgH
(ListUser.class); 3Sl2c
q&d5V~q
private UserService userService; l#^weXSlk
5rUDRFO6
private Page page; Kp?j\67S
![3l
K
privateList users; AroYDR,3+
M\6u4p!G!
/* i27KuPjC
* (non-Javadoc) C{2y*sx
* 6hAMk<kx?i
* @see com.opensymphony.xwork.Action#execute() CA5q(ID_
*/ =L9;8THY
publicString execute()throwsException{ d 8%sGH
Result result = userService.listUser(page); P-)`FB
page = result.getPage(); E-"b":@:
users = result.getContent(); Eq6.
s)10
return SUCCESS; 6):iu=/i/
} SPo}!&p$~
Yu_`
>so
/** N={0A
* @return Returns the page. E%vT(Kz
*/ `VD7VX,rp*
public Page getPage(){ 3 Q~zli:
return page; {bMOT*X=A
} WNWtQ2]
BX-fV|
/** |$&v)
* @return Returns the users. Y JMaIFt
*/ `z~L0h
publicList getUsers(){ K~Z$NS^W&
return users; |[/'W7TV%?
} BfdS3VrZ/
53O}`xX!6
/** 4M*!'sG\
* @param page j5V{,lf
* The page to set. Yrmd
hSY
*/ M:d }
P
publicvoid setPage(Page page){ |rwx;+
this.page = page; :BpXi|n;
} RAAu3QKu
:3.!?mOe2
/** 7 jiy9[
* @param users +5qY*$dn
* The users to set. 4'G osQ85
*/ %WAaoR&u
publicvoid setUsers(List users){ E4qQ
this.users = users; 8;5@5Au
} +~za6
`*w!S8} m;
/** GyLp&aa
* @param userService cs0rz= ZdH
* The userService to set. T/iZ"\(~w
*/ KSxZ4Y
publicvoid setUserService(UserService userService){ ,^@z;xF
this.userService = userService; <P0&!yN
} JlhI3`X;/
} ]qO*(m:}o
=H/ 5
n7(/ml+Q_
~w"e 2a
dlCmSCp%
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ^\7GFpc
z4wG]]Kh*
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 !MEA@^$#
. 9@y*_9
么只需要: M=#g_*d
java代码: 3h**y
%^
iG+=whvL
uL
|O<
<?xml version="1.0"?> *s$:"g-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Q&8epO |J
:aWC6"ik-W
1.0//EN" "http://www.opensymphony.com/xwork/xwork- b{a\j%
8RjFp2)W
1.0.dtd"> !a^'Jbb
,nSapmg
<xwork> Y%Tm
`$^V
/5m ~t.Z9M
<package name="user" extends="webwork- C(&3L[
<Y+>a#T
interceptors"> M s Q=1
1)J'
pDa
<!-- The default interceptor stack name ,$bK)|pGV
Y3bZ&G)
--> '4,>#D8@O
<default-interceptor-ref Esdw^MGL2
AYv7-!Yk
name="myDefaultWebStack"/> epG!V#I
?b x ak
<action name="listUser" fF.sT7Az+
cXbQ
class="com.adt.action.user.ListUser"> E^? 3P'%^
<param ="P&!lu
7.bPPr&
name="page.everyPage">10</param> +u;RFY^
<result TnJJ& "~3b
Ue(\-b\)
name="success">/user/user_list.jsp</result> 'wVi>{?
</action> EM!9_8 f
`u$lSGl
</package> PGhYkj2
XPT@ LM
</xwork> 4nKlW_{,
tf6 Zz[
^1;Eq>u
rkn'1M&u
]K|td)1X
G<Y}QhFU
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 K[l5=)G0L
'M,O(utGv
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 <ToRPx&E
[}`-KpV!;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 DVjwY_nG7
[Nu py,v
Rk!8eN Pf
23/;W|
B!((N{4H+
我写的一个用于分页的类,用了泛型了,hoho Ch73=V
,AwX7gx22
java代码: =)nJ'}x
Q:8t1ZDo
2*a5pFkb
package com.intokr.util; ))4RgS$
id[caP=`
import java.util.List; Fhga^.5U&
gl 27&'?E*
/** IqqBUH
* 用于分页的类<br> xM![
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Xo3@-D_c!c
* ]E^)d|_
* @version 0.01 xB5QM #w\
* @author cheng OM81$Xo=
*/ j7~Rw"(XQc
public class Paginator<E> { A~H@0>1
privateint count = 0; // 总记录数 3EH7HW
privateint p = 1; // 页编号 <YvW /x
privateint num = 20; // 每页的记录数 ]Rj?OSok
privateList<E> results = null; // 结果 D+y?KihE
KpT=twcK
/** Q096M 0m
* 结果总数 {xf00/
*/ r!~6.
publicint getCount(){ bWJ&SR>
return count; @a,}k<@E
} yw >Frb5p
yz=aJ
v;
H
publicvoid setCount(int count){ eVj7%9
this.count = count; Sl'{rol'
} Z29aRi
hGRHuJ
/** Qh+zs^-?
* 本结果所在的页码,从1开始 \-8aTF
* B_*Ayk
* @return Returns the pageNo. 0cq<!{d
*/ |)S*RQb\
publicint getP(){ 9I(00t_
return p; F>eo.|'
} <GLn!~Px@5
:QC |N@C
/** ]KQQdr
* if(p<=0) p=1 )r?-_qj=
* AWi+xo|
* @param p e m
*/ ^U##9KkP
publicvoid setP(int p){ ] !n3j=*
if(p <= 0) &@=W+A=c~
p = 1; ""*g\
this.p = p; TX;)}\
} -b|"%e<'
tG~[E,/`
/** qg:EN~E#
* 每页记录数量 sG\K$GP!
*/ <GF^VT|Ce
publicint getNum(){ GJF &id
return num; Ss_}@p ^
} VOIni<9y
MBAj.J
/** '_5|9
}
* if(num<1) num=1 HiBI0)N}
*/ Tgh?=]H
publicvoid setNum(int num){ _!_1=|[
if(num < 1) h1l%\ 3ZH
num = 1; _3.rPS,s
this.num = num; sPXjU5uq#
} ;#9ioGx
LR';cR;
/** /4@
[^}x
* 获得总页数 V7.g,
*/ @C^wV
publicint getPageNum(){ pRd'\+
return(count - 1) / num + 1; SPXvi0Jg
} q^?a|l
H \'1.8g/
/** 6P:fM Y
* 获得本页的开始编号,为 (p-1)*num+1 m)3M) 8t
*/ aO S,%J^?
publicint getStart(){ <fF|AbC:
return(p - 1) * num + 1; @b,6W
wc
} j=Izwt>
b`@C #qB
/** >239SyC-,
* @return Returns the results. <XQwu*_\
*/ e<*qaUI
publicList<E> getResults(){ xVgm 9s$"c
return results; 3
^K#\*P
} GdY@$&z{i
{+nf&5E 6
public void setResults(List<E> results){ V)l:fUm2
this.results = results; C ocw%Yl
} CWocb=E
,.}%\GhY
public String toString(){ ([}08OW@
StringBuilder buff = new StringBuilder Pq8oK'z-
ar6+n^pi0]
(); C#^y{q
buff.append("{"); Em^~OM3U$q
buff.append("count:").append(count); =J)<Nx.gA
buff.append(",p:").append(p); miu?X !
buff.append(",nump:").append(num);
8?Ju\W
buff.append(",results:").append 7 4MxU
}Z FoCMM
(results); o-7{\%+M
buff.append("}"); ;{L[1OP%e
return buff.toString(); 0c`nk\vUy
} yCav;ZS_
Wbei{3~$Y"
} CbC[aVA=
BV:Ca34&
MP)Prl>