Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 *sQ.y
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .-'_At4g
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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 m@Dra2Cv'@
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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 S{RRlR6Z
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分页支持类: .]H/u
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java代码: 7'OR;b$
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package com.javaeye.common.util; 9OFH6-;6`\
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import java.util.List; T
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publicclass PaginationSupport { "n{';Q)
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publicfinalstaticint PAGESIZE = 30; 9_?<T;]"
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privateint pageSize = PAGESIZE; HE{UgU:tY
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privateList items; 7O8 @T-f+2
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privateint totalCount; _xH<R
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privateint[] indexes = newint[0]; M)ao}m>
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privateint startIndex = 0; 33KCO
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public PaginationSupport(List items, int C:t?HLY)fG
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totalCount){ t*; KxQ+'?
setPageSize(PAGESIZE); RT3(utwO
setTotalCount(totalCount); HL]J=Gh
setItems(items); ?(U;T!n
setStartIndex(0); dl3;A_ 2
} }A]eC
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public PaginationSupport(List items, int `mW~ {)x
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totalCount, int startIndex){ ~(^pGL3<
setPageSize(PAGESIZE); WUjRnzVM
setTotalCount(totalCount); #_x5-?3
setItems(items); .I EHjy\+
setStartIndex(startIndex); 5!S#}=f=
} vE8BB$D
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public PaginationSupport(List items, int 6]Q#4
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totalCount, int pageSize, int startIndex){ IiRQ-,t1
setPageSize(pageSize); (J.Z+s$:2
setTotalCount(totalCount); M9o/6
setItems(items); /\<x8BJ
setStartIndex(startIndex); &o7PB`(l
} yH]Q;X'
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publicList getItems(){ rM,f7hm[S*
return items; K?[Vz[-Fc
} Hc@_@G
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publicvoid setItems(List items){ T@{ab1KV
this.items = items; &*'^uCna
} u?fM.=/N
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publicint getPageSize(){ aem gGw<
return pageSize; C>x)jDb?
} ;,6C&|n]w
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publicvoid setPageSize(int pageSize){ B|"/bQ
this.pageSize = pageSize; _aOs8#(X
} X<. l(9$
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publicint getTotalCount(){ nyqX\m-
return totalCount; gED|2%BXb
} *xpn-hCp<
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publicvoid setTotalCount(int totalCount){ .%7Le|Fb"
if(totalCount > 0){ ; U7P{e05
this.totalCount = totalCount; T?f{.a)
int count = totalCount / #9r}Kr=P
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pageSize; F(."nUrf
if(totalCount % pageSize > 0) Q|{b8K
count++; LTzdg >\oJ
indexes = newint[count]; 0wNlt#G;{
for(int i = 0; i < count; i++){
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indexes = pageSize * xR%NiYNQz
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i; Rvu5#_P
} 0M&n3s{5I
}else{ 0fBwy/:
this.totalCount = 0; T:'JA
} w.aEc}@(^
} ;b=diZE
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publicint[] getIndexes(){ F.aG7
return indexes; "5k6FV
} J;>~PXB
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publicvoid setIndexes(int[] indexes){ sT!?nn3O`
this.indexes = indexes; CP;<B1
} )V>OND
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publicint getStartIndex(){ %5zIh[!1$
return startIndex; x+za6e_k"
} v@GhwL
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publicvoid setStartIndex(int startIndex){ f&^"[S"\f
if(totalCount <= 0) Zqe$S
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this.startIndex = 0; RV{%@1Pu
elseif(startIndex >= totalCount) @J5TDq @
this.startIndex = indexes fUY05OMZ
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[indexes.length - 1]; i ?M-~EKu
elseif(startIndex < 0) f'5
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this.startIndex = 0; j}/).O
else{ /{[<J<(8
this.startIndex = indexes j5:4/vD
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[startIndex / pageSize]; _6h.<BR
} *My9r.F5o
} V3cKdlu Na
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publicint getNextIndex(){ 6QT&{|q=
int nextIndex = getStartIndex() + =X5w=(&
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pageSize; }0anssC
if(nextIndex >= totalCount) nu1XT 1q1
return getStartIndex(); -eh .Tk
else +L'Cbv= "
return nextIndex;
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} rA?<\*
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publicint getPreviousIndex(){ JCBX?rM/
int previousIndex = getStartIndex() - OS<GAA0
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pageSize; wY%t# [T3
if(previousIndex < 0) m6K7D([f
return0; pRE^;
4}z
else R(&3})VOa
return previousIndex; WH39=)D%u
} E`qX|n
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} NV(jp'i~
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抽象业务类 IOC$jab@
java代码: r9M3rj]
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/** _s0)Dl6K
* Created on 2005-7-12 h/:LC 7
*/ T@P~A)>yo
package com.javaeye.common.business; :a2[d1
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import java.io.Serializable; ;3& wO~lW
import java.util.List; ONpvx5'#
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import org.hibernate.Criteria; f9Xa}*
import org.hibernate.HibernateException; .9z}S=ZK
import org.hibernate.Session; 'CJ_&HR
import org.hibernate.criterion.DetachedCriteria; vyWx{@
import org.hibernate.criterion.Projections; ^jS1g*nrN
import S[y_Ewzq
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org.springframework.orm.hibernate3.HibernateCallback; hMS:t(N{
import ZR|s]'
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org.springframework.orm.hibernate3.support.HibernateDaoS =Xid"$
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upport; m*)jndXY
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import com.javaeye.common.util.PaginationSupport; :wRfk*Ly
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public abstract class AbstractManager extends [K4k7$
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HibernateDaoSupport { %$)Sz[=
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privateboolean cacheQueries = false; z,dFDl$
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privateString queryCacheRegion; ${ DSH
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publicvoid setCacheQueries(boolean YB)I%5d;{
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cacheQueries){ MZX@Gi<S[
this.cacheQueries = cacheQueries; 5=9Eb
} (+zU!9}I1
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publicvoid setQueryCacheRegion(String bh\2&]Di/
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queryCacheRegion){ *YQXxIIq
this.queryCacheRegion = e_rEu'[av
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queryCacheRegion; &FZ~n?;hQ
} |L}tAS`8
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publicvoid save(finalObject entity){ ZN'B@E=p
getHibernateTemplate().save(entity); D^];6\=.i
} S&cN+r
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publicvoid persist(finalObject entity){ ?f:0GE7
getHibernateTemplate().save(entity); -Fop<q\b
} ]D2d=\
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publicvoid update(finalObject entity){ pf yJL?_%
getHibernateTemplate().update(entity); !@T~m1L
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} ose)\rM'
~ `{{Z&
publicvoid delete(finalObject entity){ D7B g!*
getHibernateTemplate().delete(entity); %(\et%[]
} ka_R|xG\
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publicObject load(finalClass entity, ?4W6TSW-'
):L0{W{
finalSerializable id){ rC/z8m3z
return getHibernateTemplate().load ^8?px&B y:
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(entity, id); RWJyd=
} JRtDjZ4>
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publicObject get(finalClass entity, {HVsRpNEf
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finalSerializable id){ criNeKa
return getHibernateTemplate().get w,!N{hv(
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(entity, id); 4/2@^\?i)
} 9wC='
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publicList findAll(finalClass entity){ ySlGqR1H
return getHibernateTemplate().find("from r|953e
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" + entity.getName()); 9A\\2Zz6F
} a3 t||@v!
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publicList findByNamedQuery(finalString %w3tzE1Hq
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namedQuery){ 5N2`e3:I
return getHibernateTemplate `4qt mbj
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().findByNamedQuery(namedQuery); 5J6~]J
} RAxp2uif
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publicList findByNamedQuery(finalString query, vC^n_
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finalObject parameter){ xl(R|D))
return getHibernateTemplate >H]|R }h
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().findByNamedQuery(query, parameter); C'joJEo
} i%r+/D)KvG
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publicList findByNamedQuery(finalString query, Lhxg5cd
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finalObject[] parameters){ >#5jO9
return getHibernateTemplate 7<93n`byM
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().findByNamedQuery(query, parameters); fvV5G,lD3h
} Ot~buf'|
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publicList find(finalString query){ _6\"U5*Y
return getHibernateTemplate().find rJCu6
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(query); S@WT;Q2Z
} di~ [Ivw
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publicList find(finalString query, finalObject 2-@z-XKn
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parameter){ 0gJ{fcI
return getHibernateTemplate().find WWVQJ{,}
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(query, parameter); S2~im?^21
} I=4G+h5p
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public PaginationSupport findPageByCriteria =5 $BR<'
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(final DetachedCriteria detachedCriteria){ Ak@y"!wnM
return findPageByCriteria $gaGaB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); $8NM[R.8^4
} 8}|!p>
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public PaginationSupport findPageByCriteria tx}=c5
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(final DetachedCriteria detachedCriteria, finalint 'TDp%s*;
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startIndex){ _5v]69C#
return findPageByCriteria fvZ[eJ
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(detachedCriteria, PaginationSupport.PAGESIZE, }ykc
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startIndex); kntULI$`
} Ca#T?HL
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public PaginationSupport findPageByCriteria p)* x7~3e
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(final DetachedCriteria detachedCriteria, finalint FtybF
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pageSize, MZdj!(hO
finalint startIndex){ ;Bne=vjQp
return(PaginationSupport) SnGXEQ
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getHibernateTemplate().execute(new HibernateCallback(){ (kSb74*g
publicObject doInHibernate NdM \RD_R
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(Session session)throws HibernateException { 256V
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Criteria criteria = '$q3 Ze
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detachedCriteria.getExecutableCriteria(session); t9&=; s
int totalCount = t7,** $ST
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((Integer) criteria.setProjection(Projections.rowCount M~g@y$
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()).uniqueResult()).intValue(); 3tCT"UvTD
criteria.setProjection ZKVM9ofXRi
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(null); mN'sJ1L-
List items = pzxlh(a9
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criteria.setFirstResult(startIndex).setMaxResults ;tfGhHpQn
E{[>j'dwc
(pageSize).list(); { &pBy
PaginationSupport ps = b:x*Hjf
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new PaginationSupport(items, totalCount, pageSize, rz5@E
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startIndex); L^L.;1
return ps; >UV?nXP}
} 4&H&zST//m
}, true); "2`/mtMon
} Ss'Dto35Q
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public List findAllByCriteria(final Hx ojxZwm
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DetachedCriteria detachedCriteria){ [B%:!Q)@
return(List) getHibernateTemplate @gm!D`YL
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().execute(new HibernateCallback(){ (_eM:H=e>
publicObject doInHibernate /rv=mlpRL
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(Session session)throws HibernateException { b`|,rfq^AZ
Criteria criteria = G[Jz(/yNH
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detachedCriteria.getExecutableCriteria(session); |7b@w;q,D
return criteria.list(); r\m2Oo)]
} _j|U>s
}, true); -@/!u9l
} 5>rjL;
@|@6pXR.
public int getCountByCriteria(final (sEZNo5 n
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DetachedCriteria detachedCriteria){ $GIup5
Integer count = (Integer) Ikgia:/-Z
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getHibernateTemplate().execute(new HibernateCallback(){ 1f0maN
publicObject doInHibernate ~{[,0,lWU
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(Session session)throws HibernateException { ~0Mw\p%}
Criteria criteria = ivPX_#QI
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detachedCriteria.getExecutableCriteria(session); !6`&0eY
return n)R[T.E)+
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criteria.setProjection(Projections.rowCount /
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()).uniqueResult(); iI!g1
} qEnmms 1
}, true); ^-7-jZ@jz
return count.intValue(); z2OXCZ*/
} &_$xMM,X
} u1/q8'RW
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用户在web层构造查询条件detachedCriteria,和可选的 'jBtBFzP-
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 5z9'~Gfb
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PaginationSupport的实例ps。 hPrE
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ps.getItems()得到已分页好的结果集 YPS,[F'B.
ps.getIndexes()得到分页索引的数组 @1)C3(=A
ps.getTotalCount()得到总结果数 8rSu,&<
ps.getStartIndex()当前分页索引 q??N,
ps.getNextIndex()下一页索引 G>W:3y
ps.getPreviousIndex()上一页索引 zl["}I(*n
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 j%E9@#
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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 3G-f+HN^E
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一下代码重构了。 B~/ejC!
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我把原本我的做法也提供出来供大家讨论吧: gBXJ/BW$y
cUM#|K#6
首先,为了实现分页查询,我封装了一个Page类: 4L[-[{2
java代码: \}NZ]l
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/*Created on 2005-4-14*/ 9/LJtM
package org.flyware.util.page; 5 }F6s
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/** qAR}D~ t
* @author Joa cLCzLNyKl
* >rzpYc'~w
*/ [:C!g#o
publicclass Page { `PvGfmYOl
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/** imply if the page has previous page */ XP_V
privateboolean hasPrePage; XW9
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OX/}j_8E^(
/** imply if the page has next page */ .=-K7.X.)
privateboolean hasNextPage; .6#Y-iJqc
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/** the number of every page */ JIyIQg'5i
privateint everyPage; mbRN W
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/** the total page number */ Z]Iyj
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privateint totalPage; nH]F$'rtA
[XP3
/** the number of current page */ Ws(#ThA
privateint currentPage; Gr?[s'Ze
{,rVA(I@
/** the begin index of the records by the current =1Mh%/y
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query */ }];_ug*
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privateint beginIndex; SRx `m,535
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/** The default constructor */ ]1<O [d
public Page(){ q^hL[:ms#
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} zWh[U'6
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/** construct the page by everyPage zbDM+;
* @param everyPage Y SE6PG
* */ U:.
public Page(int everyPage){ ~y(-j[
this.everyPage = everyPage; 3yfq*\_uXw
} ;9R;D,Gk!
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/** The whole constructor */ w&7-:."1i
public Page(boolean hasPrePage, boolean hasNextPage, R2af>R
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int everyPage, int totalPage, !be6}
int currentPage, int beginIndex){ B|Rnh;B-
this.hasPrePage = hasPrePage; 5Go&+|c vJ
this.hasNextPage = hasNextPage; xNh#= 6__9
this.everyPage = everyPage; oiq7I@Y`x
this.totalPage = totalPage; ,/;mK_6
this.currentPage = currentPage; )k8=< =s
this.beginIndex = beginIndex; ,HxsU,xiG
} ]r{-K63P{!
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/** Uk02VuS
* @return JxP=[>I
* Returns the beginIndex. D %`64R
*/ yuvt<kz
publicint getBeginIndex(){ _G!lQ)1
return beginIndex; IwIk;pB O
} >69+e+|I
nz|;6?LCLY
/** FBM 73D@`
* @param beginIndex U/2g N
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* The beginIndex to set. XB)e;R
*/ `MgR/@%hr
publicvoid setBeginIndex(int beginIndex){ Hut
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this.beginIndex = beginIndex; 9lA@ K[
} YWSo:)LY
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/** ('W#r"
* @return }_0?S0<#
* Returns the currentPage. B+ GPTQSTb
*/ E@"+w,x)
publicint getCurrentPage(){
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return currentPage; 5|xFY/%
} P f6rr9
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/** {8Hrb^8!
* @param currentPage J7emoD[
* The currentPage to set. X6!u(plVQ
*/ }@4m@_gR?
publicvoid setCurrentPage(int currentPage){ A2uSH@4
this.currentPage = currentPage; sL~TV([6/
} -a]oN:ERb
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/** ]&yO>\MgJB
* @return e<l Wel
* Returns the everyPage. #It{B
*/ QgEG%YqB
publicint getEveryPage(){ :r:5a(sq
return everyPage; f_9%kEXICt
} %D\TLY
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/** )1lR;fD
* @param everyPage @;fdf 3ian
* The everyPage to set. '_g8fz
3
*/ #_QvnQ?I
publicvoid setEveryPage(int everyPage){ @?3u|m |Z
this.everyPage = everyPage; %@G<B
} ,/m<= `*N|
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/** :!N 5daK
* @return bh6Mh<+
* Returns the hasNextPage. $9+}$lpPd
*/ WA8Qt\Q
publicboolean getHasNextPage(){ 2
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return hasNextPage; $[VKM|Zjw
} pYI`5B4
P@lExF*D1:
/** ]3NH[&+
* @param hasNextPage 2l{g$44
* The hasNextPage to set. e8a_)TU?
*/ P_z3TK
publicvoid setHasNextPage(boolean hasNextPage){ @PZ&/F^
this.hasNextPage = hasNextPage; ul?'kuYk
} s)_7*DY
p;"pTGoWi
/** Jv1.Yz
* @return 82YTd(yB
* Returns the hasPrePage. GW
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*/ ^p|MkB?uM
publicboolean getHasPrePage(){ AJiEyAC!)5
return hasPrePage; WT;=K0W6&
} E O52 E|
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/** S?D|"#-,
* @param hasPrePage 5:hajXd
* The hasPrePage to set. $`i$/FE
*/ SWz+.W{KQ"
publicvoid setHasPrePage(boolean hasPrePage){ I+!w9o2nZ
this.hasPrePage = hasPrePage; RN5\,>+
} XK`>#*"V
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/** >e/;
* @return Returns the totalPage. zg.'
* *%:p01&+
*/ zQ(li9
publicint getTotalPage(){ 2ELw}9
return totalPage; HN7(-ml=B
} o*_[3{FU
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/** 7ib~04
* @param totalPage -n?|,cO
* The totalPage to set. _'ltz!~
*/ Dq)V] Zx
publicvoid setTotalPage(int totalPage){ E
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this.totalPage = totalPage; (*;b\h
} @N7X(@O
>~){KV1~
} -N<s =
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R(74Px,/
^o,P>u!9
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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 DxdiXf[j
v,bes[Ik
个PageUtil,负责对Page对象进行构造: WNrgqyM
java代码: a9j
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/*Created on 2005-4-14*/ JfxD-9U^>u
package org.flyware.util.page; iBVV5 f
1.+0=M[h
import org.apache.commons.logging.Log; luACdC
import org.apache.commons.logging.LogFactory; 7;:R\d6iL
gXZC%S
/** Wz)s#
* @author Joa kO{A]LnAH
* RZ#b)l
*/ }xcA`w3u2?
publicclass PageUtil { +)k%jIi!
?){V7<'?y
privatestaticfinal Log logger = LogFactory.getLog K'kWL[Ut!
: KhAf2A
(PageUtil.class); &<2~7?$!
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/** [`Seh $
* Use the origin page to create a new page v^1_'PAXu
* @param page Jz(wXp
* @param totalRecords {&nL'R
* @return N9QHX
*/ [0<N[KZ)
publicstatic Page createPage(Page page, int _^]2??V
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totalRecords){ hC2 @Gq
return createPage(page.getEveryPage(), HJWk%t<
b)/,
page.getCurrentPage(), totalRecords); FC[8kq>Hk
} -XBD WV
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/** k|Mj|pqA
* the basic page utils not including exception "I+71Ce
{ZQ|Ydpk
handler 5q4sxY9T
* @param everyPage <*k]Aa3y
* @param currentPage Mtxn@m{i;"
* @param totalRecords P(AcDG6K
* @return page {[&$W8Li
*/ /`$9H|
publicstatic Page createPage(int everyPage, int sg0HYb%_E
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currentPage, int totalRecords){ bit@Kv1<C
everyPage = getEveryPage(everyPage); s.y wp{EF
currentPage = getCurrentPage(currentPage); Z
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int beginIndex = getBeginIndex(everyPage, *O6q=yg;K:
{Aq2}sRl{
currentPage); 'KL!)}B$h
int totalPage = getTotalPage(everyPage, mtfEK3?2*
5}-e9U
totalRecords); (rF XzCI
boolean hasNextPage = hasNextPage(currentPage, IbV 7}
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totalPage); Qmbl_#
boolean hasPrePage = hasPrePage(currentPage); ";vP77|m7R
J+IkTqw
returnnew Page(hasPrePage, hasNextPage, _}G1/`09#
everyPage, totalPage, )Pj8{.t4
currentPage, H!6nIS9yxt
~#
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beginIndex); %N.qu_,IZ
} w&U>w@H^
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privatestaticint getEveryPage(int everyPage){ @xu/&pbI
return everyPage == 0 ? 10 : everyPage; Cx,)$!1
} ? |}%A9
H<YhO&D*u
privatestaticint getCurrentPage(int currentPage){ Y#[Wv1hi
return currentPage == 0 ? 1 : currentPage; bi=IIVlH
} @)hrj2Jw
s"jNS1B
privatestaticint getBeginIndex(int everyPage, int sD_"
J|Af`HJ
currentPage){ %+Az
X
return(currentPage - 1) * everyPage; 6<%W8m\
} W'0(0;+G/j
97XGJ1HI
privatestaticint getTotalPage(int everyPage, int 3B+
F'k
Gd=l{~
totalRecords){ u=mJI*
int totalPage = 0; rE WPVT
|izf|*e
if(totalRecords % everyPage == 0) zc,kHO|
totalPage = totalRecords / everyPage; <kY||
else wlY6h4c
totalPage = totalRecords / everyPage + 1 ; >WKlR` J%
IQ9jTkW l
return totalPage; T@. $Zpz
} #c2InwZV
bM%c*_$F7
privatestaticboolean hasPrePage(int currentPage){ x>E**a?!L
return currentPage == 1 ? false : true; HDTdOG)
} s</llJ$
y
8./)W&/
privatestaticboolean hasNextPage(int currentPage, Q<e`0cu|p
lvyD#|P
int totalPage){ CYxrKW
l:'
return currentPage == totalPage || totalPage == e>oE{_e
k*;2QED
0 ? false : true; /G>reG,G
} qZ39TTQ*p
te+5@k#t
)kE(%q:*P$
} fC$~3v
0H V-e
$B
iG7,[#
Q9~UL^bF
? }k~>. \
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 [SW@ "C!
(5"BKu1t
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 R.g'&_zx
[|sKu#yW
做法如下: Q&rf&8iH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9u 'hCi(
p,?8s%
的信息,和一个结果集List: UeRx ^
java代码: (VPT% l6
=f)S=0U F
h&!k!Su3#
/*Created on 2005-6-13*/ tk^1Ga3
package com.adt.bo; ZOFBT(oV
-S=Zsr\
import java.util.List; u+]v.Mt
{PM)D [$i
import org.flyware.util.page.Page; 7p?6j)rj
/~_Cb=7
/** ta+'*@V+G
* @author Joa
,i2%FW
*/
yG0Wr=/<?
publicclass Result { HrA6wn\O
jl<rxO?-F
private Page page; eiZv|?^0
Z`xz |:D+
private List content; (k"oV>a|
xG_ ;F
/** h^P>pI~
* The default constructor fB5Bh;K
*/ Vgs( feGs
public Result(){ !oU$(,#9
super(); XN"V{;OP1
} gKg2Ntxj
->}K- n ),
/** E{r_CR+8
* The constructor using fields A.vcE
* +1p>:cih
* @param page uNnwz%w
* @param content 1!\!3xa V
*/ zQ
{g~x
public Result(Page page, List content){ nJ4h9`[>V
this.page = page; t4?g_$>
this.content = content; o})4Jt1vj
} w2~(/RgO
BzA(yCu$:
/** }se)=7d8
Z
* @return Returns the content. n/s!S &
*/ 3h";
2
publicList getContent(){ ~`hI|i<]
return content; 7F`QN18>(
} 6!bA~"N
vD) LRO
Z
/** hC]c
=$=7
* @return Returns the page. .,,?[TI
*/ 5S$HDO&
public Page getPage(){ ;k7` `
return page; ER5Q` H
} |i?AtOt@f
N jq#@*>[p
/** 2{p`"xX
* @param content 'A!Dg
* The content to set. [p!C+|rro
*/ Eg-b5Z);
public void setContent(List content){ 2I ?HBz1v
this.content = content; =]xNpX)
} M=o,Sav5*
UXQ{J5Ox+
/**
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* @param page Yc?t aL)
* The page to set. {, APZ`q|
*/ h,140pW
publicvoid setPage(Page page){ a4`@z:l
this.page = page; @dCu]0oNI
} Oku4EJFJ
} tO[+O=d
W]2;5`MM
nQ$N(2<Fe
,C&h~uRi#f
7=QV ^G
2. 编写业务逻辑接口,并实现它(UserManager, K:y q^T7
4#2iL+
UserManagerImpl) &@+K%qW[e
java代码: :-"J)^V
_hh|/4(
t_]UseP$RF
/*Created on 2005-7-15*/ lmmyDg1R
package com.adt.service; f6|3|
+
m]"YR_
import net.sf.hibernate.HibernateException; ?sS'T7r
v
B. P64"w
import org.flyware.util.page.Page; Qgx~'9
er#we=h
import com.adt.bo.Result; }7.q[ ^oF
~:t2@z4p
/** nr-mf]W&
* @author Joa ItaJgtsV
*/ J$EEpL
publicinterface UserManager { @tj0Ir v
vq5I 2
public Result listUser(Page page)throws CIaabn
/Hx0=I
HibernateException; teB{GR
/GeS(xzQ
} &pba~X.u
=OHDp7GXO>
Xj@Kt|&`k
<.v6w*+{/
}`M6+.z3F
java代码: (w^&NU'e
Wey\GQ`"8
7>~iS@7GV
/*Created on 2005-7-15*/ )xK!i.
package com.adt.service.impl; 5-3gsy/Mo
A"k,T7B
import java.util.List; uB^]5sqfk
Z*QRdB%,
import net.sf.hibernate.HibernateException; #rC/y0niH
.Lp-'!i
import org.flyware.util.page.Page; w[+!c-A:H
import org.flyware.util.page.PageUtil; 6\Z^L1973
.o8Gi*PEY
import com.adt.bo.Result; A+l"
import com.adt.dao.UserDAO; Lf:Z
(Z>
import com.adt.exception.ObjectNotFoundException; zc{C+:3$^
import com.adt.service.UserManager; SeTU`WLEm
x('yBf
/** jl@8pO$
* @author Joa W!(Q_B
*/ cs5Xd
publicclass UserManagerImpl implements UserManager { i,HAXPi
yh)q96m-V=
private UserDAO userDAO; h`Mf;'P
p[eRK .$!
/** Cf N; `
* @param userDAO The userDAO to set. {8MF!CG]
*/ ~;W%s
publicvoid setUserDAO(UserDAO userDAO){ d]^i1
this.userDAO = userDAO; FN
R&
:
} FdqUv%(Em
x9e
9$ww}
/* (non-Javadoc) #n"/9%35f`
* @see com.adt.service.UserManager#listUser \2`U$3Q
@RP|?Xc{?
(org.flyware.util.page.Page) qSd
$$L^
*/ $3ILVT
public Result listUser(Page page)throws *8p</Q
=jN]ckn
HibernateException, ObjectNotFoundException { I}WJ0}R
int totalRecords = userDAO.getUserCount(); uE$o4X
if(totalRecords == 0) +\%zy=
throw new ObjectNotFoundException nGVqVSxKT
)3AT=b
("userNotExist"); OOCeZ3yF(
page = PageUtil.createPage(page, totalRecords); f-<6T
List users = userDAO.getUserByPage(page); -,dQ&Qf?
returnnew Result(page, users); "Tv7*3>
} PwW @I~@>
^XM;D/Gp~
} ^n/uY94E)p
W<Lrfo&=Y]
U6Ak"
"ivqh{ ,
Eg*3**gTO
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ShpnFuH
"}! rM6 h
询,接下来编写UserDAO的代码: 8; 8}Oq
3. UserDAO 和 UserDAOImpl: F0Hbklr
java代码: }U9jsm
2#3R]zIO
dK: "
/*Created on 2005-7-15*/ !U_L7
package com.adt.dao; TpgBS4q
AX+d? M
import java.util.List; __j8jEV
cAS_?"V
a
import org.flyware.util.page.Page; L])w-
Q\L5ZJ%y/
import net.sf.hibernate.HibernateException; ozLJ#eOE9
M;qL)vf
/** "44?n <1
* @author Joa ]'(7T#
*/ 09Y?!,
publicinterface UserDAO extends BaseDAO { OU@x1G{Cy
&F_rg,q&_
publicList getUserByName(String name)throws "\;wMR{
#~;8#!X
HibernateException; G4' U;
Cg pT(E\E
publicint getUserCount()throws HibernateException; Aw;vg/#~md
w9$8t9$|
publicList getUserByPage(Page page)throws fhKiG%i'l
nM-SDVFM
HibernateException; f<Tz#w&6W
@BUqQ9q:
} x9l0UD*+g
bpa
O`[*
Ch"8cl;Fm
h;qy5KS
o!`O
i5
java代码: orH0M!OtS!
m\M+pjz
%aBJ+V F
/*Created on 2005-7-15*/ jUvA<r
package com.adt.dao.impl; |qcFmy
9zYiG3 d
import java.util.List; C_cs(}wi
Y{vwOs
import org.flyware.util.page.Page; X|E+K
kN|5
J
import net.sf.hibernate.HibernateException; 8KwCwv
import net.sf.hibernate.Query; ~+ s*\~
Wk#h,p3
import com.adt.dao.UserDAO; jS3(>
5b1uD>,;y
/** yISQYvSN
* @author Joa %M#?cmt
*/ 6$s0-{^
public class UserDAOImpl extends BaseDAOHibernateImpl :q64K?X
xVkTRCh
implements UserDAO { ?koxt44
!Nl.Vb
/* (non-Javadoc) BCUt`;q ]B
* @see com.adt.dao.UserDAO#getUserByName TT2cOw
#3K,V8(
(java.lang.String) [Z5[~gP3
*/ M?xpwqu\
publicList getUserByName(String name)throws yvd
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sCtw30BL
HibernateException { 8HFXxpt[G
String querySentence = "FROM user in class o9Txo
(tYU
U M( l%
com.adt.po.User WHERE user.name=:name"; S6T!qH{6
Query query = getSession().createQuery :Wg-@d
u-QO>3oY6
(querySentence); 6b]1d04hT
query.setParameter("name", name); YWRE&MQ_
return query.list(); wD6!#t k
} ~|'y+h89
4W!\4Va
/* (non-Javadoc) k%]DT.cE
* @see com.adt.dao.UserDAO#getUserCount() s[3![
"^Y
*/ p,w|=@=
publicint getUserCount()throws HibernateException { Zj1ZU[BEcL
int count = 0; t{Hh&HX
String querySentence = "SELECT count(*) FROM =_8
UZk.
?""\
user in class com.adt.po.User"; 4|6&59?pnc
Query query = getSession().createQuery |^Ew<
7|QGY7Tf
(querySentence); Ht|",1yr+
count = ((Integer)query.iterate().next (_w
%
2cCWQ"_,
()).intValue(); ~V2ajM1Z&O
return count; S5~`T7Ra
} s(AJkO'`
TBZ-17+
/* (non-Javadoc) (0E U3w?]
* @see com.adt.dao.UserDAO#getUserByPage ^]$$)(jw
)L |tn
(org.flyware.util.page.Page) [d4,gEx`Q\
*/ w"cM<Ewu
publicList getUserByPage(Page page)throws _0,"vFdj
T8$%9&j!UE
HibernateException { qyg*n>nt
String querySentence = "FROM user in class rDVgk6
J3;Tm~KJ_
com.adt.po.User"; <ROpuY\!l
Query query = getSession().createQuery 2GSgG.%SSM
i2$*}Cu
(querySentence); L5Urg*GNL
query.setFirstResult(page.getBeginIndex()) lPY@{1W
.setMaxResults(page.getEveryPage()); pC*BA<?Rg
return query.list(); +0]'| t F>
} nVxq72o@
8rFaW
} sFLcOPj-%
}0QN[$H!
7}Bj|]b)~
n`% 2Mj c
5k69F
至此,一个完整的分页程序完成。前台的只需要调用 @l'G[jN5
%=V" CJ$|
userManager.listUser(page)即可得到一个Page对象和结果集对象 %a5t15 9
eGLO!DdxZ
的综合体,而传入的参数page对象则可以由前台传入,如果用 /D0RC
VCjq3/[_
webwork,甚至可以直接在配置文件中指定。 ##H;Yb
D!oZ?dGCo6
下面给出一个webwork调用示例: *B1x`=
java代码: }sv!=^}BY3
F\5X7ditD
4otl_l(`yv
/*Created on 2005-6-17*/ e^QVn\<c
package com.adt.action.user; O#Z/+\U
n@
4@,
import java.util.List; dIk'pA^d
SBTPTb
import org.apache.commons.logging.Log; VJDoH
import org.apache.commons.logging.LogFactory; .d~\Ysve
import org.flyware.util.page.Page; *(G&B\
r}
Lb3`'
import com.adt.bo.Result; 3cqQL!Gm
import com.adt.service.UserService; }f#_4ACaD
import com.opensymphony.xwork.Action; 3?2<WEYr
T"?Y5t`(
/** 1Dq<{;rWb
* @author Joa Yt+h2ft!
*/ oV9z(!X/
publicclass ListUser implementsAction{ #--olEj!
II;Te7~
privatestaticfinal Log logger = LogFactory.getLog y7z( &M@
GAw(mH*
(ListUser.class); 7X}TB\N1
sw$2d
private UserService userService; CvK3H\.&;k
^gOww6$ <
private Page page; XE1$K_m
+~Tu0?{Z 0
privateList users; s\gp5MT
fW(/Loh
/* NQX>Qh
2
* (non-Javadoc) cJDd0(tD!
* S`m,S4-eD
* @see com.opensymphony.xwork.Action#execute() ?^u^im
*/ \\:|Odd
publicString execute()throwsException{ +;Cr];b3
Result result = userService.listUser(page); =gjDCx$|
page = result.getPage(); sI,W%I':d
users = result.getContent(); >2b`\Q*<
return SUCCESS; +
P7o4]:/
} 19c@ `?
rrqQCn9
/** }D*yr3b
* @return Returns the page.
q0&$7GH4
*/ #HAC*n
public Page getPage(){ C\}/"
return page; dNiH|-$an
} vXv;1T
TL0[@rr4
/** l_{8+\`!
* @return Returns the users. bT)]'(Xy
*/ J?&l*_m;t
publicList getUsers(){ 65TfFcQ<S
return users; ?o*I9[Z)
} W),l
4!.(|h@
/** J2VTo: In
* @param page V}WB*bE
* The page to set. M.q=p[
*/ YXW%]Uy+
publicvoid setPage(Page page){
4x;_AN
this.page = page; @7oL#-
} x =q;O+7]
j%IF2p2
/** 9?<{_'
* @param users 3g~'5Ao
* The users to set. 0Ua%DyJ
*/ qS|\JG
publicvoid setUsers(List users){ "Gb1K9A
im
this.users = users; yQNV@T<o
} X;oa[!k
-n 80&
/** r!PpUwod
* @param userService J aTp}#
* The userService to set. sEJC-$
*/ -G7TEq)
publicvoid setUserService(UserService userService){ 7&qy5y-Ap
this.userService = userService; BZ54*\t
} #Lv2Zoi>G
} o1cErI&q"
).^}AFta
?L&'- e@
}|u4 W?H
*!s;"U
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, !$-\;<bZw
ZOCDA2e(j
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 '(bgs
Ms~{9?
么只需要: CHrFM@CM
java代码: |KSy`lY-j>
~cTN~<{dq
;s`sn$@
<?xml version="1.0"?> "#[!/\=?:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +gtrt^:]l
&e6CJ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- EQ'V{PIfj
h%}/Cmx[
1.0.dtd"> n2)q}_d
AC>`'Gx
<xwork> h4q|lA6!k8
<Utnz)
<package name="user" extends="webwork- K+;e4_\
r E}%KsZ
interceptors"> ='`/BY(m[
)+:EJH~
<!-- The default interceptor stack name fQ#l3@in
S30?VG9U0f
--> $2W%2rZ
<default-interceptor-ref \v'p/G)g
0NS<?p~_S
name="myDefaultWebStack"/> N[s}qmPha
9 FB19
<action name="listUser" o4|M0
|&RU/ a
class="com.adt.action.user.ListUser"> &*+'>UEe5
<param j'A_'g'^
8_{X1bj
name="page.everyPage">10</param> xai*CY@cQ
<result :Zlwp6
< 1uZa
name="success">/user/user_list.jsp</result> M7pOLP_1jB
</action> u6AA4(
*MKO
I'
</package> 6}d.5^7lr
wne,e's}
</xwork> gt@m?w(
wOU_*uY@6'
C{U?0!^
be.*#[
>CHrg]9
U~:-roQ(\
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 {\81i8b]
j0oR)du
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。 Ff)8Q.m
4y|BOVl
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3 2&;`]C
GPN]9
o~`/_+
\NPmym_6J
hgPa6Kd
我写的一个用于分页的类,用了泛型了,hoho {*G9|#[/@
G?O1>?4C
java代码: !|^|,"A)
=;Au<|
l9{hq/V
package com.intokr.util; ~%<X0s|
:D~D U,e'
import java.util.List; Y]'Z7<U}*E
*4\:8
/** TM%|'^)
* 用于分页的类<br> m*&]!mM"0G
* 可以用于传递查询的结果也可以用于传送查询的参数<br> f6hnTbJ
* 0"<H;7K#W
* @version 0.01 oB(?_No7
* @author cheng BC^ :=
*/ y%"{I7!A
public class Paginator<E> { 'j#*6xD
privateint count = 0; // 总记录数 , qMzWa
privateint p = 1; // 页编号 <? q?Mn
privateint num = 20; // 每页的记录数 %~4M+r6T
privateList<E> results = null; // 结果 <FV1Wz
!|S(Ms
/** Yl
Zso2
* 结果总数 X_q\S g
*/ *&