Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;UxP
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K"r*M.P>
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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 [D!jv"
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分页支持类: .C--gQpIv
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java代码: zzyHoZJP
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package com.javaeye.common.util; d!$Z(W0
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import java.util.List; _]Zs,Hy
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publicclass PaginationSupport { #W|'1
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publicfinalstaticint PAGESIZE = 30; ;1a~pF S
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privateint pageSize = PAGESIZE;
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privateList items; t]YC"%[S
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privateint totalCount; '#&os`mQ
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privateint[] indexes = newint[0]; ^_f+15]D
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privateint startIndex = 0; `b^Ru+(dM
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public PaginationSupport(List items, int }nL7T'$>
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totalCount){ N|6MP
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setPageSize(PAGESIZE); 8@tPm$
setTotalCount(totalCount); ](s'L8(x
setItems(items); 6*3.SGUY
setStartIndex(0); RS^lKJ1 U
} L>3x9
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public PaginationSupport(List items, int gy_>`16K
x= 5N3[5
totalCount, int startIndex){ lqm1!5dt
setPageSize(PAGESIZE); h]TQn)X]
setTotalCount(totalCount); [DF,^4g
setItems(items); 7D;cw\ |
setStartIndex(startIndex); hUF5fZqii
} ~FN9 [aJF+
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public PaginationSupport(List items, int {$wjO7Glp
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totalCount, int pageSize, int startIndex){ c|#8T*`C
setPageSize(pageSize); eY|
setTotalCount(totalCount); z[3L2U~6
setItems(items); +w+}b^4
setStartIndex(startIndex); r_-_a(1R:
} {PVW D7
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publicList getItems(){ ,d {"m)r<
return items; iy%ZQ[Un
} dfij|>:*0
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publicvoid setItems(List items){ RE/~#k@a
this.items = items; 1fZ(l"
} u)~C;f)
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publicint getPageSize(){ !K'}K>iT
return pageSize; o
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} U4b0*` o
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publicvoid setPageSize(int pageSize){ P7{gfiB
this.pageSize = pageSize; Uk6HQQ
} x;8A!8w
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publicint getTotalCount(){ ~x]jB
return totalCount; 70eb]\%
} R~S;sJ& c
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publicvoid setTotalCount(int totalCount){ [rSR:V?"a
if(totalCount > 0){ [D<1CF
this.totalCount = totalCount; C,NJb+J
int count = totalCount / /JWGifH
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pageSize; ZOZ+ Y\uU
if(totalCount % pageSize > 0) eep1I
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count++; T-U}QM_e
indexes = newint[count]; 'LO^<
for(int i = 0; i < count; i++){ :gep:4&u
indexes = pageSize * 2fWTY0
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} -@0GcUE:r
}else{ x3o]U)^
this.totalCount = 0; 9f<MQ6_UU
} }<9cL'
} v%iof1 T'
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publicint[] getIndexes(){ CD~z=vlK-
return indexes; ~wkj&yVT
} Ljp%CI[i
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publicvoid setIndexes(int[] indexes){ V 7Ek-2M
this.indexes = indexes; =5(>q5Z*
} @T'i/}nl
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publicint getStartIndex(){ _s .G
return startIndex; v5QqS8u_C
} 2AO~HxF
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publicvoid setStartIndex(int startIndex){ .K p
if(totalCount <= 0) >8qQK r\"
this.startIndex = 0; @CZT
elseif(startIndex >= totalCount) E: $P=%b
this.startIndex = indexes ,#L=v]
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[indexes.length - 1]; &C"L
elseif(startIndex < 0) Y]B)'[=h
this.startIndex = 0; WZ*ws[dVI
else{ VCD:3U 8
this.startIndex = indexes 8j=}u/T@F
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[startIndex / pageSize]; 5a hVeY
} ;;:-l99
} l@\#Ywz
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publicint getNextIndex(){ YTexv;VNb|
int nextIndex = getStartIndex() + \l]DQaOEe
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pageSize; i03w1pSH,
if(nextIndex >= totalCount) 'gTb A?+@5
return getStartIndex(); -\
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else +/)#( j@
return nextIndex; S|]X'f
} b-{=s+:
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publicint getPreviousIndex(){ TwVlg;
int previousIndex = getStartIndex() - \<y#R~7s
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pageSize; \\u<S=G
if(previousIndex < 0) S&b*rA02zp
return0; VBcy9|lD
else OeS\7
return previousIndex;
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} y*tZ
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} /p+>NZ"b
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抽象业务类 DW_1,:,?7l
java代码: }L# _\
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/** BE_ay-
* Created on 2005-7-12 ;I}kQ!q
*/ q(.:9A*0
package com.javaeye.common.business; b;cdIl!3
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import java.io.Serializable; bdF.qO9
import java.util.List; /$'AjIg4:&
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import org.hibernate.Criteria; :QB<?HaS'
import org.hibernate.HibernateException; g'V>_u#(
import org.hibernate.Session; -1UD0(
import org.hibernate.criterion.DetachedCriteria; D-4f >
import org.hibernate.criterion.Projections; 7zSLAHW
import or';A'k
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org.springframework.orm.hibernate3.HibernateCallback; F=a<~EpZ
import Ct=-4
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org.springframework.orm.hibernate3.support.HibernateDaoS Ire\i7MF:
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upport; w &(|e <
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import com.javaeye.common.util.PaginationSupport; ]A<~XIu
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public abstract class AbstractManager extends %Cv D-![0
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HibernateDaoSupport { ` M3w]qJ<}
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privateboolean cacheQueries = false; f^"N!f a
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privateString queryCacheRegion; Gq }U|Z
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publicvoid setCacheQueries(boolean viMzR(JU
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cacheQueries){ "huFA|`
this.cacheQueries = cacheQueries; dK2p7xo
} 4*cU<
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publicvoid setQueryCacheRegion(String vWf;
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queryCacheRegion){ jhg;%+KB
this.queryCacheRegion = ?)1{)Erf8x
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queryCacheRegion; =MLcm^b
} OC<5E121>Y
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publicvoid save(finalObject entity){ J1:1B,^y
getHibernateTemplate().save(entity); 1PP $XJtyD
} ~ ArP9
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publicvoid persist(finalObject entity){ 4y'OMRy
getHibernateTemplate().save(entity); Wv/%^3
} (m:Zk$
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publicvoid update(finalObject entity){ 8_6Q~
getHibernateTemplate().update(entity); pD01,5/
} FZtfh
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publicvoid delete(finalObject entity){ 6N;wqn
getHibernateTemplate().delete(entity); (3#Cl
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} 4W)B'+ZK8
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publicObject load(finalClass entity, Bxfc}vC.
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finalSerializable id){ $W9{P;
return getHibernateTemplate().load $[/&74#0HX
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(entity, id); HsHB!mQV
} D6Goa(!9d
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publicObject get(finalClass entity, Y>E zTV
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finalSerializable id){ e*;c(3>(
return getHibernateTemplate().get ulkJR-""&
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(entity, id); eL\;Nf+Zp
} >ey\jDr#O
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publicList findAll(finalClass entity){ KB'qRnkc
return getHibernateTemplate().find("from sPMa]F(
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" + entity.getName()); pk3<|
} \7l-@6'7
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publicList findByNamedQuery(finalString L_+k12lm
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namedQuery){ R@6zGZ1
return getHibernateTemplate jlBanGs?
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().findByNamedQuery(namedQuery); we;G]`@?
} wm$}Pch
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publicList findByNamedQuery(finalString query, {6c2{@
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finalObject parameter){ 7"w2$*4 '0
return getHibernateTemplate 3`B6w$z>(
n ;$5Cq!v=
().findByNamedQuery(query, parameter); ?kZTI (
} {FIXc^m'
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publicList findByNamedQuery(finalString query, k-HCeZ
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finalObject[] parameters){ l*kPOyB
return getHibernateTemplate Zuw?58RE\
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().findByNamedQuery(query, parameters); _-9@qe
} ?}RSwl
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publicList find(finalString query){ ]"1`+q6i
return getHibernateTemplate().find 0LfU=X0#7
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(query); m"fNK$_d
} E !a|Xp
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publicList find(finalString query, finalObject -x'z
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parameter){ +AHUp)
return getHibernateTemplate().find (A?H1 9
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(query, parameter); 1e>s{
} =7C%P%yt
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public PaginationSupport findPageByCriteria :L1dyVA{
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(final DetachedCriteria detachedCriteria){ BvR-K\rx
return findPageByCriteria 91q8k=p
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); -Y*bSP)\
} zD(`B+
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public PaginationSupport findPageByCriteria awOd_![c'
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(final DetachedCriteria detachedCriteria, finalint H]$)Eg%6
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startIndex){ 't_[dSO
return findPageByCriteria t: IN,Kl4
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(detachedCriteria, PaginationSupport.PAGESIZE, {2+L@
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startIndex); <IC~GqXv
} EC\yzH*X
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public PaginationSupport findPageByCriteria E[*Fz1>
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(final DetachedCriteria detachedCriteria, finalint ,WG<hgg-U)
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pageSize, "7v @Rye
finalint startIndex){ 2con[!U
return(PaginationSupport) m<w"T7
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getHibernateTemplate().execute(new HibernateCallback(){ <6fv1d+v
publicObject doInHibernate * 0|IXGr
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(Session session)throws HibernateException { HS.^y
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Criteria criteria = >TP7 }u|
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detachedCriteria.getExecutableCriteria(session); S=nP[s
int totalCount = ecgtUb8K
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((Integer) criteria.setProjection(Projections.rowCount u_'!_T L
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()).uniqueResult()).intValue(); ^RP)>d9Xp{
criteria.setProjection DZv=\<$,LF
[ e8x&{L-_
(null); |<Gl91
List items = ]ZoD'-,
.p=sBLp8
criteria.setFirstResult(startIndex).setMaxResults *0}3t<5
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(pageSize).list(); .-IkL|M
PaginationSupport ps = 8?i7U<CB
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new PaginationSupport(items, totalCount, pageSize, 0q*r
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startIndex);
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return ps; `KCh*i
} Da v PYg
}, true); d5>H3D{49
} |0\0a&tkPl
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public List findAllByCriteria(final u@.>Z{h
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DetachedCriteria detachedCriteria){ RKa}$
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return(List) getHibernateTemplate ZWm8*}3]7_
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().execute(new HibernateCallback(){ J8"[6vI d~
publicObject doInHibernate LS5vW|]w
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(Session session)throws HibernateException { Q3 eM2i8Y
Criteria criteria = e+]6OV&+
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detachedCriteria.getExecutableCriteria(session); `zR+ tbm
return criteria.list(); :KKa4=5L
} 3 AHY|
}, true); |hO~X~P
} c(/VYMJZ&
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public int getCountByCriteria(final %\kOLE2`
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DetachedCriteria detachedCriteria){ ErT{(t7
Integer count = (Integer) 7-~Q5Kr.
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getHibernateTemplate().execute(new HibernateCallback(){ `- \/$M9s=
publicObject doInHibernate Hi
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(Session session)throws HibernateException { ;=9
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Criteria criteria = }HG#s4
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detachedCriteria.getExecutableCriteria(session); v$)q($}p
return /Ux*u#
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criteria.setProjection(Projections.rowCount &I({T`=
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()).uniqueResult(); r,]#b[:.s|
} QeDQo
}, true); e }*0ghKI
return count.intValue(); ~=wCwA|1
} Dgql?+2$
} mrJQ#
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用户在web层构造查询条件detachedCriteria,和可选的 )%X;^(zKM
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 G|m1.=DJm
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PaginationSupport的实例ps。 KZbR3mi,
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ps.getItems()得到已分页好的结果集 ?,=f\Fz!
ps.getIndexes()得到分页索引的数组 e8EfQ1 Ar
ps.getTotalCount()得到总结果数 Dl&GJ`&:p
ps.getStartIndex()当前分页索引 <X_!x_x
ps.getNextIndex()下一页索引 !~ZP{IXyo
ps.getPreviousIndex()上一页索引 m,R Dr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ya
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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 o]LRzI
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一下代码重构了。 "{E qhR~
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我把原本我的做法也提供出来供大家讨论吧: f7hXQ|$
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首先,为了实现分页查询,我封装了一个Page类: $>R(W=Q
java代码:
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/*Created on 2005-4-14*/ rxO2js
package org.flyware.util.page; AY SSa 1}
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/** ir:d'g1k
* @author Joa
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* )ZejQ}$
*/ ;U`X 6d
publicclass Page { >~\w+^2f8
_}mK!_`
/** imply if the page has previous page */ jAND7&W
privateboolean hasPrePage; t=R6mjb
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/** imply if the page has next page */ =3 +l
privateboolean hasNextPage; p\bFdxv#
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/** the number of every page */ cE{ =(OQ
privateint everyPage; M]HgIL@9#
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/** the total page number */ 8V$3b?]
privateint totalPage; L7mz#CMWf
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/** the number of current page */ =ZsGT
privateint currentPage; R<zG^m
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/** the begin index of the records by the current !RlC~^
-
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query */ *OdX u&5
privateint beginIndex; g6sjc,`
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/** The default constructor */ fj4^VXD
public Page(){ n~Szf
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} GIv){[i
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/** construct the page by everyPage nSY-?&l6P
* @param everyPage ~E=\t9r
* */ -U>7
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public Page(int everyPage){ fw{,bJ(U
this.everyPage = everyPage; .h;Se
} c-5jYwV
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/** The whole constructor */ '5};M)w
public Page(boolean hasPrePage, boolean hasNextPage, 3D)b*fPc
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int everyPage, int totalPage, (Q-I8Y8l8
int currentPage, int beginIndex){ qi+&|80T.
this.hasPrePage = hasPrePage; [.q(h/b
this.hasNextPage = hasNextPage; r(}nhU Q%E
this.everyPage = everyPage; K@@9:T$
this.totalPage = totalPage; >Wh3MG6
this.currentPage = currentPage; y67uH4&Vm
this.beginIndex = beginIndex; ggou*;'
} !%mi&ak(Rn
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/** Q-zdJt
* @return l_v*7d
* Returns the beginIndex. 1.SkIu%
*/ H/+{e,SW"
publicint getBeginIndex(){ wq4nMY:#
return beginIndex; * Zd_
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} _2jw,WKr
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/** kb|eQtH
* @param beginIndex bZ#X9fT
* The beginIndex to set. z/1hqxHl
*/ n6d^>s9J
publicvoid setBeginIndex(int beginIndex){ *\LyNL(
this.beginIndex = beginIndex; Y&,rTa
} JCQ:+eqt
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/** $o^e:Y,
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* @return lEfBe)7+
* Returns the currentPage. i=8UBryr'e
*/ -3mgza
publicint getCurrentPage(){ rR!U;
return currentPage; r] t )x*
} F^'v{@C
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/** F14(;'Az
* @param currentPage )!C7bTv 4
* The currentPage to set. <*YO~S(R
*/ w4{y"A
publicvoid setCurrentPage(int currentPage){ k,X74D+
this.currentPage = currentPage; aqfL0Rg+`
} ck$2Ue2`@w
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/** oP]L5S&A
* @return ogeRYq,g
* Returns the everyPage. S+FQa7k
*/ G&o64W;-s
publicint getEveryPage(){ ,U%=rfB~
return everyPage; y~p4">]
} Dq`~XS*
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/** -SJSTO[/J
* @param everyPage *mV&K\_
* The everyPage to set. aRKv+{K
*/ k
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publicvoid setEveryPage(int everyPage){ ?
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this.everyPage = everyPage; @xJCn}`Zj
} 8ath45G @
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/** C<t RU5|
* @return p!GZCf,
* Returns the hasNextPage. M]B3vPA/v
*/ QSmJ`Bm
publicboolean getHasNextPage(){ `Z8^+AMc
return hasNextPage; 0IFlEe[>#
} sJ7sjrEp1
</yo9.
/** lzoeST
* @param hasNextPage VV\Xb31J
* The hasNextPage to set. !2tw, QM
*/ e;;):\p4
publicvoid setHasNextPage(boolean hasNextPage){ yId;\o B
this.hasNextPage = hasNextPage; y.fs,!|%@
} &9@gm--b:
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/** fkBLrw
* @return {~nvs4X
* Returns the hasPrePage. kdBV1E+:C
*/ /u?9S/
publicboolean getHasPrePage(){ _-6e0sr Z
return hasPrePage; F(E<,l2[
} V{FE [v_
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/** #|ddyCg2
* @param hasPrePage cdN/Qy
* The hasPrePage to set. #Jv43L H
*/ fPrb%
publicvoid setHasPrePage(boolean hasPrePage){ Ivjw<XP6K
this.hasPrePage = hasPrePage; GY7s
} _iq2([BpL
JE9>8+
/** wlL8X7+:
* @return Returns the totalPage. 0`Gai2\1@
* R|H[lbw
*/ =
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publicint getTotalPage(){ Me<du&
T
return totalPage; \KNdZC?V2
} r!~(R+,c
+]_nbWL(%
/** u x#.:C|
* @param totalPage [NZ-WU&&LP
* The totalPage to set. WzlS^bZ
*/ +.wT
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publicvoid setTotalPage(int totalPage){ )+*{Y$/U
this.totalPage = totalPage; }z?xGW/k
} W8x[3,gT
gjQ=8&i
} vi<X3G6Xh
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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 FXeV6zfrE
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个PageUtil,负责对Page对象进行构造: Dw*Arc+3V
java代码: -}< d(c
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/*Created on 2005-4-14*/ R|$[U
package org.flyware.util.page; xHm/^C&px
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import org.apache.commons.logging.Log; (GnVwJ<v9V
import org.apache.commons.logging.LogFactory; [\88@B=jXP
w/O<.8+
/** erXy>H[;
* @author Joa 'HJ/2-=
* *$JB`=Q
*/ D7M0NEY
publicclass PageUtil { ^t`f1rGR
%8a=mQl1^
privatestaticfinal Log logger = LogFactory.getLog j=FMYd8$y
M q76]I%
(PageUtil.class); xkF$D:sP
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/** ~c!Rx'
* Use the origin page to create a new page ot]>}[
* @param page x3gwG)Sf
* @param totalRecords \ibCR~W4
* @return 32s5-.{c/f
*/ Is<x31R
publicstatic Page createPage(Page page, int >1m)%zt
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totalRecords){ " \`BPN
return createPage(page.getEveryPage(), W0C{~|e
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page.getCurrentPage(), totalRecords); @l)\?IEF@f
} (rAiDRQ[
)\D2\1e(c
/** uXjoGcW
* the basic page utils not including exception k{?!O\yY
Go-wAJ>
handler Y+!Ouc!$
* @param everyPage wH+FFXGJs
* @param currentPage 4=~ 9v
* @param totalRecords W)|c[Q\
* @return page Z+r%_|kZ
*/ mVa?aWpez
publicstatic Page createPage(int everyPage, int _yiRh:
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currentPage, int totalRecords){ ,tcP=fdk]
everyPage = getEveryPage(everyPage); "3\oQvi.
currentPage = getCurrentPage(currentPage); |
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int beginIndex = getBeginIndex(everyPage, (W7;}g ysh
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currentPage); eVZa6la"
int totalPage = getTotalPage(everyPage, .4H_Zt[2
f3/SO+Me}
totalRecords); Hde]DK,d
boolean hasNextPage = hasNextPage(currentPage, bK!,Pc<
W\&WS"=~
totalPage); }Q!h ov
boolean hasPrePage = hasPrePage(currentPage); Q^*G`&w,
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returnnew Page(hasPrePage, hasNextPage, d&NCFx
everyPage, totalPage, D8)O4bh
currentPage, \m(ymp<c`
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beginIndex); K5 5} Wi
} !'Pk
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privatestaticint getEveryPage(int everyPage){ Y0 @'za^y
return everyPage == 0 ? 10 : everyPage; "kcpA#uD|
} #.<*; rB
o G(0i
privatestaticint getCurrentPage(int currentPage){ w9G_>+?E
return currentPage == 0 ? 1 : currentPage; f0/jwfL
} JX2mTQ
Fl B, (Cm
privatestaticint getBeginIndex(int everyPage, int ;3 G~["DA
$?[1#%
currentPage){ _= o1?R
return(currentPage - 1) * everyPage; "L9C
} N|UBaPS|o
0q:(-z\S4
privatestaticint getTotalPage(int everyPage, int t9?R/:B%
O3_D~O
."
totalRecords){ n^* >a
int totalPage = 0; 6W)xj6<@
*eHA:
A_I
if(totalRecords % everyPage == 0) J
ZVr&KZN
totalPage = totalRecords / everyPage; U(rr vNt:t
else Ix*BI9E
totalPage = totalRecords / everyPage + 1 ; [LJ705t
f%bc64N(
return totalPage; zj~8>QnKk
} Zx}NFcn
Gojl0?
privatestaticboolean hasPrePage(int currentPage){ x?%rx}h
return currentPage == 1 ? false : true; rFKo E%
} AeNyZ[40T
1 ;_{US5FR
privatestaticboolean hasNextPage(int currentPage, g,00'z_D
jf$JaY
int totalPage){ bHhC56[M
return currentPage == totalPage || totalPage == ,"P5D&,_
.'l.7t
0 ? false : true; Zk~nB}Xw
} 0t5Q9#RY
s,1pZT <E
eNIkiJ$uS
} BengRG[
u3Zzu \{
n%83jep9
E\{^0vNc
Vpug"aR&_
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 yf
`.%
3S[w'
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 T^/Gj|N*
z1Bj_u{
做法如下: :NwMb^>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )z]q"s5 Y
:N^@a-
的信息,和一个结果集List: :)KTZ
java代码: Ybs=W<-
844tXMtPB\
vDu0
/*Created on 2005-6-13*/ p{A}p9sjx
package com.adt.bo; }4bB7,j
p{mxk)A
import java.util.List; '#cT4_D^lI
uznoyj6g
import org.flyware.util.page.Page; .jU|gf:x
v YRt2({}Z
/** +zFV~]b
* @author Joa , aRJ!AZ
*/ r*X}3t*
publicclass Result { D%c7JK
w?V[[$
private Page page; 8\qCj.>S
&[?u1qQ%o
private List content; 7h9 fQ&y
v$gMLu=
/** c8k6(#\
* The default constructor &+E'1h10
*/ K#9(|2J%
public Result(){ xG *lV|<7>
super(); ~pd1)
} bR>o!(M'Z\
"!%w9
/** dO 1-c`
* The constructor using fields 88 tFB
* Sb:zN'U
* @param page 0[Xt,~
* @param content CX&yjT6`
*/ eZN3H"H
public Result(Page page, List content){ 7]M,yIwc
this.page = page; G1#Bb5q:
this.content = content; ]YisZE4s
} RE`J"&
9A/Kn]s(jj
/** )Dk0V!%N
* @return Returns the content. cXLV"d
*/ %!ER @&1f&
publicList getContent(){ 0j
a
return content; ~uhyROO,G"
} X/`#5<x
:/yr(V{
/** [6,]9|~
* @return Returns the page. J'G`=m"-'
*/ .R$+#_
public Page getPage(){ s0XRL1kWr
return page; .T#y N\S1
} #q~3c;ec
|
Q1ubS
/** ecY ^C3+S
* @param content Ac5o K
* The content to set. 5oT2)yz
*/ RS||KA])J
public void setContent(List content){ Q
!RVD*(
this.content = content; !
kOl$!X4
} (l3UNP
n3l"L|W^(<
/** s{"`=dKT
* @param page I |<+'G
* The page to set. 9z|>roNe
*/ L6[rvM|9_
publicvoid setPage(Page page){ L5zG0mC8
this.page = page; DK@w^ZW6JA
} e~t}z_>F
} :"<B@Z
6PzN>+t^y
7/^TwNsv
~q8V<@?
Zv1Bju*y
2. 编写业务逻辑接口,并实现它(UserManager, 7'{Yz
sO{0hZkc
UserManagerImpl) ~*' 8=D?)
java代码: |z(Ws
|oBdryi
a!0?L0_W&
/*Created on 2005-7-15*/ 7/D9n9F
package com.adt.service; siss_1J
2#n$x*CY
import net.sf.hibernate.HibernateException; ZHiICh|et%
uhw5O9
import org.flyware.util.page.Page; +/@ZnE9s
RK~FT/
import com.adt.bo.Result; shDt&_n
HjUw[Yz+6
/** I*vj26qvg
* @author Joa _} X`t8L h
*/ vHI"C %
publicinterface UserManager { w371.84
*xv/b=
public Result listUser(Page page)throws XC$+ `?
Y&05
*b"
HibernateException; ](9{}DHV
G7/?hky 0.
} qh)!| B
-9H!j4]T?
N}l]Ilm$34
3Q*RR"3
uZ0 $s$
java代码: SRG!G]?-
!7ZfT?&
WkDn
/*Created on 2005-7-15*/ j6R{
package com.adt.service.impl; 0IPhVG~#
t7!>5e)C}
import java.util.List; t5jhpPVf
,3@15j
import net.sf.hibernate.HibernateException; :|m~<'g
vY0V{u?J
import org.flyware.util.page.Page; LG&Q>pt.
import org.flyware.util.page.PageUtil; '#4mDz~
QzFv ;
import com.adt.bo.Result; &Xl_sDvt
import com.adt.dao.UserDAO; /_k hFw
import com.adt.exception.ObjectNotFoundException; ,],JI|Rl8c
import com.adt.service.UserManager; kXZV%mnT7
UB&S 2g
/** rt@-Pw!B
* @author Joa e\
l,gQP
*/ S)'q:`tZo
publicclass UserManagerImpl implements UserManager { O 44IH`SI
e}Af"LI
private UserDAO userDAO; vZ nO
H8t{ >C)]
/** <E}]t,'3
* @param userDAO The userDAO to set. Y3MR:{}
*/ k,NU,^ &
publicvoid setUserDAO(UserDAO userDAO){ &W!d}, ;
this.userDAO = userDAO; a5U2[Ko80
} bF Y)o Z
kkE)zF
/* (non-Javadoc) $NGtxZp
* @see com.adt.service.UserManager#listUser bhm~Ii
$jeDVH
(org.flyware.util.page.Page) (fGJP*YO
*/ P=sK+}5`q
public Result listUser(Page page)throws E'BH7JV
_@~kYz
HibernateException, ObjectNotFoundException { #g`cih=QL
int totalRecords = userDAO.getUserCount(); 0Li'a{n 2
if(totalRecords == 0) ;DgX"Uzm
throw new ObjectNotFoundException 9CU6o:'fW
)V$!
("userNotExist"); }rMpp[
page = PageUtil.createPage(page, totalRecords); G4exk5
List users = userDAO.getUserByPage(page); Znl>*e/|
returnnew Result(page, users); q=0{E0@9({
} #L4Kwy
SiuO99'nV
} norc!?L
7si*%><X
N13;hB<
C"` 'Re5)
d$pf[DJQo
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K<7T}XzU$
8.Own=G?
询,接下来编写UserDAO的代码: :V-}Sde
3. UserDAO 和 UserDAOImpl: }zS&H-8K
java代码: 69I.*[
E5[]eg~w%{
E=_B@VJknW
/*Created on 2005-7-15*/ wyzBkRg.
package com.adt.dao; iJKm27 ">
io?{ew
import java.util.List; ~lalc ^
<,cIc]eX
import org.flyware.util.page.Page; \,bFm,kC?
Y %D*O
import net.sf.hibernate.HibernateException; WWs[]zr
g@6X|W5,J
/** wR<QeH'V
* @author Joa :-WCW);N
*/ Jgv>$u
publicinterface UserDAO extends BaseDAO { -2na::<K
bZ22O"F
publicList getUserByName(String name)throws QGz3id6
,a_{ Y+
HibernateException; H.mQbD`X
@61N[
publicint getUserCount()throws HibernateException; _BLSI8!N@
>5vl{{,$K
publicList getUserByPage(Page page)throws er7/BE&
09;'z
HibernateException; tG^ ?fc
sd@gEp)L
} FQ~ead36C
iN/!k.ybW}
[BR}4(7
RJsG]`
`"=L
java代码: aU8Ti8A>
s1vYZ
;3?J#e6;
/*Created on 2005-7-15*/ "JLhOTPaHf
package com.adt.dao.impl; |VR5Q(d
E?h2e~ ,]
import java.util.List; f{5|}PL
TNT"2FoBd
import org.flyware.util.page.Page; GKx,6E#JM
@P5@&G
import net.sf.hibernate.HibernateException; VJtTbt;>
import net.sf.hibernate.Query; 2gR_1*|
~rJw$v
import com.adt.dao.UserDAO; otH[?c?BT
Q2pboZ86
/** EC!Cv;'
* @author Joa k|c0tvp
*/ eh7r'DmAR
public class UserDAOImpl extends BaseDAOHibernateImpl yr
9)ga%
^5 =E`q".
implements UserDAO { $JSC+o(q3#
QZa#iL
/* (non-Javadoc) P7.8tM2}
* @see com.adt.dao.UserDAO#getUserByName ~+iJpW
PEn^.v@
(java.lang.String) Jas|P}{=fT
*/ {)gd|JV*
publicList getUserByName(String name)throws l3#dfW{
M9jo<+
HibernateException { -/2$P
String querySentence = "FROM user in class Qg$Nj=Cw
U\ E{-7
com.adt.po.User WHERE user.name=:name"; }vA
nP]!A5
Query query = getSession().createQuery [qMO7enu#
8=o5;]Cg
(querySentence); 4m(>" dHP
query.setParameter("name", name); 3[i!2iL.
return query.list(); G$`4.,g
} >N1]h'q>
~dr1Qi#j?
/* (non-Javadoc) GfPz^F=ie.
* @see com.adt.dao.UserDAO#getUserCount() N4DDH^h
*/ zjh9ZLu[
publicint getUserCount()throws HibernateException { L[r0UXYLV
int count = 0; 7b%Cl
String querySentence = "SELECT count(*) FROM K2K6
4_0/]:~5
user in class com.adt.po.User"; Ns= b&Uyc
Query query = getSession().createQuery [ .uaO
vFC=qLz:
(querySentence); M`fXH 3D
count = ((Integer)query.iterate().next Cj9O[
iT9Ex9RL
()).intValue(); (Tb0PzA
return count; |ylTy B
} B(Q.a&w45t
5@A=,
GPUn
/* (non-Javadoc) Q~!hr0
ZR
* @see com.adt.dao.UserDAO#getUserByPage `e=n(D
`'.x*MNF
(org.flyware.util.page.Page) .eXA.9|jm
*/ 'J0s%m|j
publicList getUserByPage(Page page)throws hg=G//
0F'UFn>{
HibernateException { rAw1g,&
String querySentence = "FROM user in class NKhR%H
u0hbM9U>
com.adt.po.User"; yzR=:0J
Query query = getSession().createQuery U`_vF~el~
)&!@O$RS8(
(querySentence); E!l1a5qB
query.setFirstResult(page.getBeginIndex()) 5GL+j%7
.setMaxResults(page.getEveryPage()); G-?9;w'@
return query.list(); !:[n3.vm
} NRF%Qd8I/2
wggHUr(g,
} ?s} E<Kr
<@!kR$Rd
`0sk2fn
nJH%pBc
[E1|jcmQ
至此,一个完整的分页程序完成。前台的只需要调用 o"M^sKz47
:I(gz~u6
userManager.listUser(page)即可得到一个Page对象和结果集对象 )nxIxr0d-
kzpbs?<;
的综合体,而传入的参数page对象则可以由前台传入,如果用
ts!aKx
w=o m7%J@l
webwork,甚至可以直接在配置文件中指定。 -\C6j
Qnx92
下面给出一个webwork调用示例: :FpBz~!a
java代码: 6WcbJ_"mq
Qs X 59d
;*H~Yb0
/*Created on 2005-6-17*/ )'|W[Sh?
package com.adt.action.user; nqJV1h
bXL a~r4\
import java.util.List; |o)
_=Fx
tKGsrgoV
import org.apache.commons.logging.Log; ^WPV
import org.apache.commons.logging.LogFactory; +%9Y7qol
import org.flyware.util.page.Page; Jc^ozw
f_XCO=8'v
import com.adt.bo.Result; =:8=5tj
import com.adt.service.UserService; OVf|4J/Yx
import com.opensymphony.xwork.Action; 0j MI)aY.
}0),b ?*e
/** L%Q *\d
* @author Joa 6WM_V9Tidq
*/ JjML!;
publicclass ListUser implementsAction{ A|Gqjy^;@
^:ngHue8~
privatestaticfinal Log logger = LogFactory.getLog e91d~
&B7KWvAy
(ListUser.class); mLA$F4/K
j=>Gfo
private UserService userService; g``4U3T%X
y36aoKH
private Page page; \>7-<7+I6
q0Pu6"^
privateList users; (OJ9@_fgG[
V@-GQP1
/* ~J:lCu
* (non-Javadoc) f L?~1i =
* muY^Fx
* @see com.opensymphony.xwork.Action#execute() ^IkMRlJh%
*/ JdEb_c3S
publicString execute()throwsException{ =K8h)B_g
Result result = userService.listUser(page); `" Pd$jW
page = result.getPage(); tRCd(Z,WY
users = result.getContent(); kA`qExw%
return SUCCESS; d^^>3L!h
} Lr&BZM
-v@^6bQVp
/** \vQ (
* @return Returns the page. {v(|_j&:o
*/ kICYPy
public Page getPage(){ S3cQC`^
return page; ~zRd||qv
} pl&GFf
o
kk#d-!
$[
/** ;\.&FMi
* @return Returns the users. /VkJ+%}+j
*/ &pl;U\dc*a
publicList getUsers(){ c[q3O**
return users; ep|u_|sB/r
} 5]JXXdt
DLZ63'
/** q1Mk_(4oJ
* @param page t[~i})yS
* The page to set. / KM+PeO
*/ !<ucwWY,
publicvoid setPage(Page page){ "&F/'';0}E
this.page = page; 2c]O Mtk
} j)Gr@F>
ccAEN
/** +.St"f/1
* @param users 6m&I_icM
* The users to set. J(60eTwQ
*/ VF.S)='>Eu
publicvoid setUsers(List users){ 2=RDAipf59
this.users = users; Jo]g{GX[
} u5[Wr :
ERplDSfO-
/** \W!<xE
* @param userService 0"Hf6xz
* The userService to set. lom4z\6
*/ akoI LX~u
publicvoid setUserService(UserService userService){ 59u7q(
this.userService = userService; 9AaixI
} **"sru;@=
} V6N#%(?3
(?(ahtT4T
UQy+&;#5
.w&Z=YM
?##GY;#
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, oT w1w
O"GzeEY7
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ZN^Q!v
EBm\rM8
么只需要: xgVt0=q
java代码: i7_BnJJX{B
N]~q@x;<)3
NDi@x"];
<?xml version="1.0"?> S5vJC-"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork mc$dR,
H0
Sw~<W%! ?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- qSR
%#
HU'}c*d]
1.0.dtd"> XUWza=BR"
@EvnV.
<xwork> h fNBWN
-.y3:^){^
<package name="user" extends="webwork- IiL?@pIq
<JlKtR&nSo
interceptors"> ~W4<M:R
q4E{?
<!-- The default interceptor stack name 3 D3K:K!FK
)xU70:X
--> G[<iVt$y
<default-interceptor-ref TG($l2
hH~Z hB
name="myDefaultWebStack"/>
7)YU ;
EC7o 3LoND
<action name="listUser" \y=,=;yv
e_e|t>nQ
class="com.adt.action.user.ListUser"> mGX;JOjZ
<param 59LIK&w
&' Ch[Wo]H
name="page.everyPage">10</param> +VfJ:[q
<result %u#pl=k}
[69aTl>/
name="success">/user/user_list.jsp</result> 2ZnTT{]_m
</action> 2w%1\TcB$
HV>W f"1
</package> +]
uY
a)xN(xp##
</xwork> ,PnEDQ|l
l\bBc,%jt
8d]=
+n!
SU:Cm:$
.w`8_v &Y
2>mDT
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 umj7-fh
v/)dsSNZ0u
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。 ){/y-ixH
WW&0FugY_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ~k&b3-A}
x;N?'"GP
N$.''D?7D
edch'H^2+P
n'&WIf3
我写的一个用于分页的类,用了泛型了,hoho St?vd+(>
^+pmZw90
java代码: aJ2-BRn
*`\>J.
,30&VW##
package com.intokr.util; btee;3`
.DT1Jvl
import java.util.List; PR Y)hb;1
|_-FQ~Hf F
/** [scPs,5Y
* 用于分页的类<br> .NabK
* 可以用于传递查询的结果也可以用于传送查询的参数<br> OyVp 3O
* Fw=-gb_.
* @version 0.01 xi-^_I
* @author cheng <K)^MLgN
*/ fO9e ;
public class Paginator<E> { ^ c:(HUo#
privateint count = 0; // 总记录数 Hkpn/,D5
privateint p = 1; // 页编号 U,/>p=s
privateint num = 20; // 每页的记录数 yNO5h]o
privateList<E> results = null; // 结果 LJT+tb?K
>%xJ e'
/** J^u8d?>r
* 结果总数 [
%r :V"
*/ b-wFnMXk+
publicint getCount(){ D:%v((Ccw
return count; (fq>P1-
} hD;[}8qN{
|d8/ZD
publicvoid setCount(int count){ 2/I^ :*e
this.count = count; Pb!kl #
} 98A ; R
Zl]\sJ1"
/** b"p,~{
* 本结果所在的页码,从1开始 7Rq;V=2YV
* ($]y*|Obn
* @return Returns the pageNo. 9NVe>\s_
*/ fAJQ8nb{@]
publicint getP(){ ,1od]]>(O
return p; 1Ocyrn
} 5gi`&t`
Wh"oL;O
/** IGVNX2
* if(p<=0) p=1 .aF+>#V=Q
* s fazrz`h
* @param p #;H+Kb5O
*/ >Efv?8$E\
publicvoid setP(int p){ 7\5;;23N4
if(p <= 0) =d`,W9D
p = 1; p9Ks=\yvL
this.p = p; 7`
&K=( .
} m"NZ; *d '
Qu!Lc:oM?
/** nKch_Jb
* 每页记录数量 :v=Yo
*/ <kt,aMw[*
publicint getNum(){ (eSa{C\
return num; m>~%.
(/x
} cs,%Zk.xjw
F+|zCEc
/** CpO!xj+
* if(num<1) num=1 uEH&]M>d_
*/ ,qyH B2v
publicvoid setNum(int num){ dtr8u
if(num < 1) MWu67">"
num = 1; ]k5l]JB
this.num = num; /wVrr%SN
} q@H?ohIH
3S ,D~L^
/** NFv9%$l-
* 获得总页数 ]_@5LvI
*/
W& w-yZ
publicint getPageNum(){ l}># p'$
return(count - 1) / num + 1; Y;4nIWe
JL
} O:WFh;c
,vl][MhM
/** \XD&0inv
* 获得本页的开始编号,为 (p-1)*num+1 Ag^Cb'3X
*/ z`]'~
publicint getStart(){ JiCDY)bu
return(p - 1) * num + 1; Q
>] v?4
} F`r=M%yh
yuWoz*:t
/**
5k {a(I
* @return Returns the results. ANZD7v6a
*/ TIYI\/a\;
publicList<E> getResults(){ (g*2OS
return results; Vnlns2pQl
} UF3WpA
}mzM'9JH
public void setResults(List<E> results){ tgKmCI
this.results = results; ,~p'p)
} VD#`1g<
|W<wPmW_{+
public String toString(){ d~u+:[\=/
StringBuilder buff = new StringBuilder )=8MO-{
x!"S`AM
(); qQv?J]l
buff.append("{"); :D`ghXj
buff.append("count:").append(count); 1$]4g/":o
buff.append(",p:").append(p); Ol"*(ea-TX
buff.append(",nump:").append(num); 615, P/
buff.append(",results:").append bzz=8n
IDyf9Zra?
(results); !7]4sXL{
buff.append("}"); 80U07tJ
return buff.toString(); LzEs_B=9
} >LRt,.hy6
:)_Ap{9J
} X!Xl
?KDI'>"-v
R-+k>_96|