Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 uO>$,s
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :Sk0?WU
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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 t=NPo+fm
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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 >,Zjlkh3
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分页支持类: kB_G L>fc
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java代码: $)vljM<<
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package com.javaeye.common.util; wo$9$~(
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import java.util.List; 4K[ E3aA
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publicclass PaginationSupport { Cy4@\X%W
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publicfinalstaticint PAGESIZE = 30; O9oYuC :q
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privateint pageSize = PAGESIZE; 6E{HNPMb>
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privateList items; X,:^})]
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privateint totalCount; D5Wo e&g,
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privateint[] indexes = newint[0]; &Vg+n0
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privateint startIndex = 0; $Lv,e\]
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public PaginationSupport(List items, int fQ=Yf ?b
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totalCount){ b%L8mX
setPageSize(PAGESIZE); TDs=VTd@Z
setTotalCount(totalCount); B/:q
setItems(items); !JzM<hyg3
setStartIndex(0); fchsn*R%-
} n@XI$>B
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public PaginationSupport(List items, int UX;?~X
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totalCount, int startIndex){ Xa=oryDt
setPageSize(PAGESIZE); tq H7M0Ry
setTotalCount(totalCount); __teh>MC
setItems(items); ^Wo/vm*]
setStartIndex(startIndex); [5e}A&
} sI7d?+
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public PaginationSupport(List items, int KPSFy<
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totalCount, int pageSize, int startIndex){ s]50Y-C
setPageSize(pageSize); -;20|US)u
setTotalCount(totalCount); ? [l[y$9
setItems(items); 6X~.J4
setStartIndex(startIndex); z85%2Apd
} juG?kL.
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publicList getItems(){ 9Bvi2
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return items; 4='Xhm
} t'|A0r$
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publicvoid setItems(List items){ m_zl*s*6
this.items = items; .T
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} =e](eA;
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publicint getPageSize(){
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return pageSize; O;z:?
} T$%r?p(s
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publicvoid setPageSize(int pageSize){ 3}(6z"r
this.pageSize = pageSize; 1)pwR3(^Fz
} ;>np2K<`
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publicint getTotalCount(){ /2l&D~d"
return totalCount; k\BJs@-
} EudX^L5U<d
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publicvoid setTotalCount(int totalCount){ (RVe,0y
if(totalCount > 0){ o}$uP5M8q
this.totalCount = totalCount; ^MIF+/bQ
int count = totalCount / N;4bEcWjp
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pageSize; kH~ z07:
if(totalCount % pageSize > 0) )UbPG`x8
count++; TwlX'iI_;
indexes = newint[count]; 7'Z-VO
for(int i = 0; i < count; i++){ YbtsJ
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indexes = pageSize * g xY6 M4
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} waI?X2
}else{ 86Hg?!<i.
this.totalCount = 0; .a2b&}/.d
} (
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} :B{Wf 2<z
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publicint[] getIndexes(){ |_."U9!Z^
return indexes; ?+av9;Kg
} ze2%#<
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publicvoid setIndexes(int[] indexes){ n2}(Pt.
this.indexes = indexes; >*s_)IH2
} m%m<-.'-
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publicint getStartIndex(){ kvcDa+#
return startIndex; Em)U`"j/9
} S&/,+x'c|
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publicvoid setStartIndex(int startIndex){ +7\$wc_1I@
if(totalCount <= 0) \ vn!SO7
this.startIndex = 0; \]C_ul'
elseif(startIndex >= totalCount) "uCO?hv0
this.startIndex = indexes #1*#3p9UL
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[indexes.length - 1]; ,ZGU\t
elseif(startIndex < 0) V=^B7a.;>
this.startIndex = 0; U\*]cw
else{ A0hKzj
this.startIndex = indexes 6$CwH!42F
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[startIndex / pageSize]; fg$#ZCi
} fi%)520
} &1/OwTI4J
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publicint getNextIndex(){ `%QXaKO-
int nextIndex = getStartIndex() + M~%P1@%
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pageSize; 88Nx/:#Y*
if(nextIndex >= totalCount) '8J!(+
return getStartIndex(); YRg"{[+#]k
else mtU{d^B
return nextIndex; {zX]41T
} Fn>KdoByN
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publicint getPreviousIndex(){ Ft
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int previousIndex = getStartIndex() - Zd5Jz+f
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pageSize; R2Es~T
if(previousIndex < 0) -pmb-#`M
return0; Gj_7wP$
else ^H"o=K8=
return previousIndex; &F-
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} QPX&P{!g
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} n6AA%? 5
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抽象业务类 Po)U!5Tm
java代码: ;0Z-
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/** tBGLEeL/.
* Created on 2005-7-12 `TPIc
*/ U\P4ts
package com.javaeye.common.business;
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import java.io.Serializable;
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import java.util.List; 486\a
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import org.hibernate.Criteria; ?(gha
import org.hibernate.HibernateException; T#qf&Q Z
import org.hibernate.Session; dM;\)jm
import org.hibernate.criterion.DetachedCriteria; oE+P=
import org.hibernate.criterion.Projections; xeFx!$3
import ee?
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org.springframework.orm.hibernate3.HibernateCallback; zb{79Os[B
import NfClR HpVc
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org.springframework.orm.hibernate3.support.HibernateDaoS ~6;I"0b5
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upport; D>y5&`
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import com.javaeye.common.util.PaginationSupport; 8r(awp
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public abstract class AbstractManager extends iHhdoY[]
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HibernateDaoSupport { P*!`AWn
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privateboolean cacheQueries = false; 4*}&nmW
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privateString queryCacheRegion; q'8*bu_
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publicvoid setCacheQueries(boolean 2"G9?)d9
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cacheQueries){ p? L%'
this.cacheQueries = cacheQueries; oYN"L
} _ \4#I(
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publicvoid setQueryCacheRegion(String )G)6D"5,+G
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queryCacheRegion){ q%x i>H.:{
this.queryCacheRegion = =Q<VU/
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queryCacheRegion; e#/&A5#Ya
} lC#wh2B6
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publicvoid save(finalObject entity){ {3
getHibernateTemplate().save(entity); O(I^:_eH
} !-`L1D_hy
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publicvoid persist(finalObject entity){ y^ skE{
getHibernateTemplate().save(entity); /C8 }5)
} zd5=W"Y;]
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publicvoid update(finalObject entity){ +r!NR?^m
getHibernateTemplate().update(entity); ]6M<c[H>
} I-^sJ@V;
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publicvoid delete(finalObject entity){ U^KWRqt
getHibernateTemplate().delete(entity); !!Ww#x~k$[
} ^gcB+
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publicObject load(finalClass entity, 48wt
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finalSerializable id){ ta{24{?M\
return getHibernateTemplate().load eOb--@~8
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(entity, id); v'?Smd1v
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} 9KX% O-'
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publicObject get(finalClass entity, L6CI9C;-b
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finalSerializable id){ !(q@sw(
return getHibernateTemplate().get KyrZ&E.`
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(entity, id); 9.(|ri
} ,+df=>$W
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publicList findAll(finalClass entity){ )ItABl[{
return getHibernateTemplate().find("from [ifw}(
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" + entity.getName()); )yyH_Ax2
} [lML^CYQ
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publicList findByNamedQuery(finalString LC]0c)v#
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namedQuery){ G%HG6
return getHibernateTemplate }~W/NP_F
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().findByNamedQuery(namedQuery); d_we?DZ|
} 5 <k)tF%
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publicList findByNamedQuery(finalString query, C')KZ|JIC
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finalObject parameter){ L|WrdT D;
return getHibernateTemplate GcN}I=4|
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().findByNamedQuery(query, parameter); w>*Jgc@A*
} YT?Lt!cl=
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publicList findByNamedQuery(finalString query, _yAY5TIv
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finalObject[] parameters){ MUbKlX
return getHibernateTemplate zlP{1z;nV
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().findByNamedQuery(query, parameters); gd
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} lZRO"[<
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publicList find(finalString query){ q`mxN!1[
return getHibernateTemplate().find X~&8^?
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(query); H_@6!R2
} DNZ,rL:h
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publicList find(finalString query, finalObject
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parameter){ {Y5@SIyE
return getHibernateTemplate().find B`)sc ~u
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(query, parameter); mC@v,"
} <xSh13<
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public PaginationSupport findPageByCriteria =c\(]xX
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria "7EK{6&jQ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7*{l\^ism;
} o5J6Xi0+
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public PaginationSupport findPageByCriteria tJu:N'=Dy
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(final DetachedCriteria detachedCriteria, finalint G9-ETj}
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startIndex){ o]tfvGvU*
return findPageByCriteria ,{G\-(\
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(detachedCriteria, PaginationSupport.PAGESIZE, ##''d||u
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startIndex); .lj5pmD
} Y [)mHs2
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public PaginationSupport findPageByCriteria h8O\sKn
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(final DetachedCriteria detachedCriteria, finalint {,uSDIOj$
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pageSize, +a*Ic8*
finalint startIndex){ -q9m@!L
return(PaginationSupport) 5cf?u3r!qJ
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getHibernateTemplate().execute(new HibernateCallback(){ >"1EN5W
publicObject doInHibernate T^]]z}k
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(Session session)throws HibernateException { (KN",u6F
Criteria criteria = jNx{*2._r
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detachedCriteria.getExecutableCriteria(session); VF11eZ"
int totalCount = 4Ia'Yr
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((Integer) criteria.setProjection(Projections.rowCount }l+_KA
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()).uniqueResult()).intValue(); Z1
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criteria.setProjection 075IW"p'
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(null); %CnVK1u!
List items = Ga9iPv
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criteria.setFirstResult(startIndex).setMaxResults KsTGae;ds
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(pageSize).list(); \C~6
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PaginationSupport ps = 72RTEGy
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new PaginationSupport(items, totalCount, pageSize, %JPr 7 }
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startIndex); rD$5]%Y
return ps; kuBtPZ
} IAkQR0fcN
}, true); 0TV16--
} TDfloDxA
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public List findAllByCriteria(final 9$U>St
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DetachedCriteria detachedCriteria){ 7hx^U90K
return(List) getHibernateTemplate jtfC3E,U
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().execute(new HibernateCallback(){ <,p$eQ)T%
publicObject doInHibernate #O~pf[[L
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(Session session)throws HibernateException { gA_oJW4_
Criteria criteria = -">Tvi4
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detachedCriteria.getExecutableCriteria(session); C$q-WoTM(
return criteria.list(); E$ 8-8[
} `}P9[HP
}, true); dk1q9Tx
} Y
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public int getCountByCriteria(final 3ONW u
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DetachedCriteria detachedCriteria){ ZTqt 4H
Integer count = (Integer) xzz@Wc^_
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getHibernateTemplate().execute(new HibernateCallback(){ $A74V[1^
publicObject doInHibernate ,1|=_M31
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(Session session)throws HibernateException { n&]J-^Tx
Criteria criteria = t:lDFv4s
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detachedCriteria.getExecutableCriteria(session); hC{2LLu;n
return E{-pkqx
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criteria.setProjection(Projections.rowCount zN9@.!?X2
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()).uniqueResult(); ~ cu+QR)
} c uAp,!
}, true); K4Nz I9@
return count.intValue(); H.n|zGQTB
} GRL42xp'*D
} { ~{D(k
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用户在web层构造查询条件detachedCriteria,和可选的 s#0m
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 biV|W@JM
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PaginationSupport的实例ps。 FDFVhcr
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ps.getItems()得到已分页好的结果集 xXV15%&
ps.getIndexes()得到分页索引的数组 b0%#=KMi
ps.getTotalCount()得到总结果数 Z^A( Q>{e
ps.getStartIndex()当前分页索引 }EfRYE$E
ps.getNextIndex()下一页索引 ou|3%&*"
ps.getPreviousIndex()上一页索引 b[n6L5P5m2
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =5pwNi_S
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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 Y'6P ~C;v
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一下代码重构了。 hoPh#? G
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我把原本我的做法也提供出来供大家讨论吧: JKXIxw>q
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首先,为了实现分页查询,我封装了一个Page类: eBECY(QMQ
java代码: g2r8J0v
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/*Created on 2005-4-14*/ \=W t{
package org.flyware.util.page; {2|sk9?W
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/** /KJWo0zo
* @author Joa Tc;BE
* eLN(NSPoS
*/ uTrGb:^
publicclass Page { rPW9lG
cz>`$Zz
/** imply if the page has previous page */ "Jyb?5
privateboolean hasPrePage; 7.^1I7O
t&bE/i_T
/** imply if the page has next page */ .|kp`-F51
privateboolean hasNextPage; =6w(9O
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id^
/** the number of every page */
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privateint everyPage;
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/** the total page number */ ORV'dr
privateint totalPage; q*>|EJR^Rw
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/** the number of current page */ xaSiG
privateint currentPage; E[_-s
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/** the begin index of the records by the current o648
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query */ @2$iFZq~
privateint beginIndex; U./1OZ&
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/** The default constructor */ .Wci@5:3
public Page(){ kObgoMT<[
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} QNm.8c$
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/** construct the page by everyPage 7\;gd4Ua1
* @param everyPage obIYC
* */ h@?BA<'S
public Page(int everyPage){ RE:$c!E!
this.everyPage = everyPage; Riz!HtyR
} &4l>_
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/** The whole constructor */ .l&<-l;UQ
public Page(boolean hasPrePage, boolean hasNextPage, </d&bS
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int everyPage, int totalPage, aib)ItNb
int currentPage, int beginIndex){ OK9D4
7X
this.hasPrePage = hasPrePage; B,dKpz;kFg
this.hasNextPage = hasNextPage; ODqWXw#
this.everyPage = everyPage; 6JL:p{RLi
this.totalPage = totalPage; qg@Wzs7c~
this.currentPage = currentPage; TBqJ.a
this.beginIndex = beginIndex; Mio~CJ"?
} 1G+?/w
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/** {YgB?kt5
* @return }h)[>I(
* Returns the beginIndex. bQM_rqjJGw
*/ |[lM2
publicint getBeginIndex(){ ddD $ 4+
return beginIndex; \=/^H
} Me*]Bh
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/** !23#Bz7
* @param beginIndex Y|iALrx
* The beginIndex to set. PUViTb
*/ ^Ru/7pw5
publicvoid setBeginIndex(int beginIndex){ FLekyJmw~
this.beginIndex = beginIndex; K:eP Il{JE
} 8.Ty
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/** A5ps|zidI
* @return &Qdd\h#
* Returns the currentPage. xem:#>&r
*/ bP 2IX
publicint getCurrentPage(){ "i1~YE
return currentPage; >m{)shBX
}
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/** Z*|qbu)
* @param currentPage ;2;Kq)j_=
* The currentPage to set. '
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*/ <4Jo1
publicvoid setCurrentPage(int currentPage){ 8BZDaiE"
this.currentPage = currentPage; 8V(#S:G35
} Q04iuhDO:
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/** GxGZxf*(
* @return ,Mwj`fgh
* Returns the everyPage. $u9y
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*/ <3>Ou(F
publicint getEveryPage(){
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return everyPage; `?VB)
} oY{r83h{
h&vq}
/** |f~p3KCfV
* @param everyPage 'I_\ELb_
* The everyPage to set. pr[[)[]/
*/ H{P"$zj`l
publicvoid setEveryPage(int everyPage){ &4yI]
this.everyPage = everyPage; |vnfY;
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} <c6C+OWT,
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/** ,g$N
* @return ET`;TfqM
* Returns the hasNextPage. X] /r'Tz
*/ s Hu~;)
publicboolean getHasNextPage(){ 4PEJ}BW
return hasNextPage; 7oDr`=q1]r
} e}e\*BL
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/** -)aBS3
* @param hasNextPage :r[`bqC;\*
* The hasNextPage to set. *~|xj,md
*/ QP?Z+P<
publicvoid setHasNextPage(boolean hasNextPage){ Dg@>d0FW
this.hasNextPage = hasNextPage; 3D
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} Px}#{fkS
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/** lV^sVN Z]
* @return UGPD5wX?
* Returns the hasPrePage. Tp`by
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*/ ('xu2 ;<
publicboolean getHasPrePage(){ 'wX'}3_/g
return hasPrePage; h2u>CXD
} rj*4ZA?
!\8j[QS!
/** )=X8kuB~
* @param hasPrePage ^m{kn8
* The hasPrePage to set. !+T+BFw.
*/ %?C{0(Z{
publicvoid setHasPrePage(boolean hasPrePage){ gRKmfJ*u
this.hasPrePage = hasPrePage; +MeEy{;
} 5HioxHL
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/** <vA^%D<\~
* @return Returns the totalPage. PZRpH
* 5Y)!q?#H
*/ fdzD6KZI
publicint getTotalPage(){ o;\0xuM@
return totalPage;
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} Srz.-,2 PF
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/** Q4Q*5>
* @param totalPage 'j!7
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* The totalPage to set. kN;l@>
*/ ^[8e|,U
publicvoid setTotalPage(int totalPage){ 9+SeG\Th
this.totalPage = totalPage; %"DEgIP
} ^&DHBx"J
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} `qSNS->
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4fZ$&)0&
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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 ~|pVz/s|G
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个PageUtil,负责对Page对象进行构造: z(3mhMJY
java代码: yGH'|`
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/*Created on 2005-4-14*/ =6q?XOM
package org.flyware.util.page; o'%F*>#v
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import org.apache.commons.logging.Log; $[[6N0}*:
import org.apache.commons.logging.LogFactory; or~o'
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/** VE6T&fz`
* @author Joa z(>{"t<C
* #v')iR"
*/ {`KgyCW:
publicclass PageUtil { pR&cdORsP
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privatestaticfinal Log logger = LogFactory.getLog ~7b'4\
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(PageUtil.class); C%"h1zWE:
o~gduNG#
/** rr*",a"}m
* Use the origin page to create a new page @| %t<{y^I
* @param page naXo <B
* @param totalRecords DhY9)>4M
* @return iX.=8~3
*/ (OYR, [*
publicstatic Page createPage(Page page, int 6k42>e*p
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totalRecords){ \h :Rw|
return createPage(page.getEveryPage(), Zo;@StN3}T
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page.getCurrentPage(), totalRecords); *WfOB2rU
} +yS"pOT
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/** bI@+Or
* the basic page utils not including exception ~VUNN[
PFG):i-?
handler Z,,Da|edH
* @param everyPage BYVp~!u
* @param currentPage }%y_LcL
* @param totalRecords xh@H@Q\
* @return page ?9v!UT
*/ y*\ M7}](
publicstatic Page createPage(int everyPage, int X&^t 8
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currentPage, int totalRecords){ )(\5Wk9(
everyPage = getEveryPage(everyPage); A,lcR:@w
currentPage = getCurrentPage(currentPage); =a?l@dI]
int beginIndex = getBeginIndex(everyPage, {.H}+ @0
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currentPage); j"_V+)SD
int totalPage = getTotalPage(everyPage, p."pI Bd
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totalRecords); T
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boolean hasNextPage = hasNextPage(currentPage, 15uVvp/
qp
totalPage); /I$g .f/#
boolean hasPrePage = hasPrePage(currentPage); F]z xx
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returnnew Page(hasPrePage, hasNextPage, 6O$OM
everyPage, totalPage, %I(N
currentPage,
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beginIndex); *u
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} 6peO9]Zy
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privatestaticint getEveryPage(int everyPage){ a%;$l_wVT:
return everyPage == 0 ? 10 : everyPage; *J8j_-i,R
} 2y
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eAu3,qoM
privatestaticint getCurrentPage(int currentPage){ isDBNXV:
return currentPage == 0 ? 1 : currentPage; 8\. #
} 0D|^S<z6
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privatestaticint getBeginIndex(int everyPage, int lx U}HM
}v0oFY$u`H
currentPage){ c(ZkK
return(currentPage - 1) * everyPage; (
y2%G=.j
} `"zX<
eO(VSjo'`
privatestaticint getTotalPage(int everyPage, int
@5acTYQ
9!_`HE+(XJ
totalRecords){ sA3 4`ZAa
int totalPage = 0; ' "~|L>F%G
jf*M}Q1jHE
if(totalRecords % everyPage == 0) zg)Z2?K|;u
totalPage = totalRecords / everyPage; t \DS}3pv
else V2i*PK
X
totalPage = totalRecords / everyPage + 1 ; 2B=yT8
[% |i
return totalPage; Cj_cu
} UR1U; k
7AV !v`
privatestaticboolean hasPrePage(int currentPage){ u{ JAC!
return currentPage == 1 ? false : true; s7(mNpo
} R\A5f\L9
iW-w?!>|m
privatestaticboolean hasNextPage(int currentPage, 2[r#y1ro
k
U*\Fa*E
int totalPage){ d=xU
f`^
return currentPage == totalPage || totalPage == O6Xu/X]
4}W*,&_
0 ? false : true; yGZb
} $khWu>b
oq^#mJL
s$&:F4=?
} :f 1*-y
IObGmc
QC \8Zy
dL |D
1 c3gHc7{t
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。 K> lA6i7?
%^2LTK(P
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 ^7Z)/c`"
\[B5j0vV,
做法如下: &P&M6v+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Zh{Pzyp
yJppPIW^
的信息,和一个结果集List: dE.R$SM
java代码: f lVQG@
p#qQGJe
#=OKY@z/
/*Created on 2005-6-13*/ :nCGqg
package com.adt.bo; xl5mI~n_~
+]Po!bN@@
import java.util.List; ht!o_0{~
a+uSCs[C
import org.flyware.util.page.Page; ",w@_}z:
['tGc{4
/** 7xMvf<1P
* @author Joa pzg|?U
*/ "n}J6
publicclass Result { )ra_`Qdcf
QO[!
private Page page; @ar%`+_
p2gdAJ
private List content; G7 UUx+ X
+x
3x
/** gLv+L]BnhH
* The default constructor gt}Atr6>_
*/ DA
"V)
public Result(){ <=7nTcO~
super(); eVf D&&@
} y]jx-wc3O
L[2qCxB'^
/** z[c8W@OJ
* The constructor using fields CqnHh@]nu
* {zcG%b WJ
* @param page Ep;uz5 ^8
* @param content l[T-Ak
*/ )4ek!G]Rb
public Result(Page page, List content){ J -z.
this.page = page; ,H7_eVLWR
this.content = content; qIZ+%ZOu
} pWRdI_
0vqH-)}
/** y$R8J:5f
* @return Returns the content. $vXY"-k
*/ ]vQa~}
publicList getContent(){ _R\FB|_
return content; arm_SyL0
} K]m#~J3d>
s=jmvvs_V}
/** zq</(5H
* @return Returns the page. ]"T157F
*/ fYP,V0P
public Page getPage(){ fF0K].
return page; 8`*5[ L~~/
} $Lstq_x+
eQ[akVMk
/** lu{
*]!
* @param content j-1V,V=
* The content to set. ~%*l>GkP*
*/ U%@PY9#
public void setContent(List content){ "> Qxb.Y}
this.content = content; PL=v,NB
} vb~%u;zrC@
\ZcI{t'a
/** )W\)kDh!
* @param page SdlO]y9E
* The page to set. O<s7VHj
*/ .\a+m
publicvoid setPage(Page page){ ]x
metv|7
this.page = page; Ms6;iW9
} pA .orx
} T/|!^qLF
\2/X$x<?X
_ooHB>sH
wetu.aMp
gaXo)o S
2. 编写业务逻辑接口,并实现它(UserManager, i`@cVYsL
Lmjd,t
UserManagerImpl) = cxO@Fu
java代码: U[pHT _U
2*D2jw
F4\:9ws
/*Created on 2005-7-15*/ R WY>`.su
package com.adt.service; Bdh*[S\u@E
-4QZ/ *
import net.sf.hibernate.HibernateException; )$^xbC#j`3
3/vtx9D
import org.flyware.util.page.Page; \/1~5mQ+
2tK~]0x
import com.adt.bo.Result; l^R:W#*+U
$CB&>?~
/** -J63'bb7oi
* @author Joa 'n7|fjX?Y
*/ e Fs5l
publicinterface UserManager { |5;,]lbt
s>G6/TTH6
public Result listUser(Page page)throws 65 zwi-
? /!Fv/
HibernateException; dwB#k$VIOw
"#wAGlH6>
} +DSbr5"VlB
)q'dX+4=eL
wrJQkven-
^kNVQJiZyG
=Jl\^u%H(x
java代码: [UkcG9
nycJZ}f:wP
\_.'/<aQ
/*Created on 2005-7-15*/ mL1ZSX
o!
package com.adt.service.impl; 1R-0b{w[
1W*Qc_5 v1
import java.util.List; ?:vg`m!*
wOL%otEf
import net.sf.hibernate.HibernateException; 53uptQ{
3SWDPy
import org.flyware.util.page.Page; z]g#2xD2
import org.flyware.util.page.PageUtil; Jy:@&c
n2*Ua/J-8
import com.adt.bo.Result; ,Z|O y|+'
import com.adt.dao.UserDAO; '(r?($s
import com.adt.exception.ObjectNotFoundException; %tkqWK:
import com.adt.service.UserManager; qX5]\nX&G
Pq~#SxA~
/** ("A45\5
* @author Joa {!(
htg;
*/ w:B&8I(n}w
publicclass UserManagerImpl implements UserManager { {C`M<2W]
suQ`a_zJ
private UserDAO userDAO; KUX6n(u
L'
_%zO
/** >}.~Y#Ge
* @param userDAO The userDAO to set. &z3_N
*/ (Ajhf}zJ
publicvoid setUserDAO(UserDAO userDAO){ 2pHR $GZ2
this.userDAO = userDAO; LL:N/1ysG
} 2O(k@M5E?
br0\O
/* (non-Javadoc) xz@*V>QT
* @see com.adt.service.UserManager#listUser ly!3~W
K&._fG
(org.flyware.util.page.Page) bg3kGt0
*/ c5f57Z
public Result listUser(Page page)throws hTAc}'^$
aEQrBs
HibernateException, ObjectNotFoundException { dG3?(}p+
int totalRecords = userDAO.getUserCount(); w2 (}pz:
if(totalRecords == 0) unYPvrd
throw new ObjectNotFoundException oVuIHb0w
U#Kw+slM
("userNotExist"); ,-d2wzhW
page = PageUtil.createPage(page, totalRecords); S%]4['Y
List users = userDAO.getUserByPage(page); *>iJ=H
returnnew Result(page, users); M2:3k
} l+(B~v
4cm~oZ
} !pa7]cZ
.}R'(gN\6
qYqd -R
9%k4Ic%P
T8LvdzS
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 kVWrZ>McK
+CEt:KQ
询,接下来编写UserDAO的代码: ^l(,'>Cn
3. UserDAO 和 UserDAOImpl: j}h%,
7
java代码: {>R933fap
,9:v2=C_
ctgH/SU
/*Created on 2005-7-15*/ t- //.
package com.adt.dao; 'bji2#z[
UT_t]m
import java.util.List; 8/"uS ;yP
Pmuk !V}f
import org.flyware.util.page.Page; ,^iT,MgNNf
99zMdo S
import net.sf.hibernate.HibernateException; ('_S1?y
;h~k B
/** +ZwTi!W
* @author Joa UA0R)BH'
*/ Dxr4B<
publicinterface UserDAO extends BaseDAO { q<g!bW%
1{xkAy0
publicList getUserByName(String name)throws odeO(zuU
_=5\ $6
HibernateException; ,E(M<n|.
wGz_IL.D
publicint getUserCount()throws HibernateException; w@N)Pu
mh_GYzd
publicList getUserByPage(Page page)throws \bSakh71
H/#WpRg
HibernateException; fK4O
N'[R:
]_y;Igaj
} Q|Pm8{8
Wu?[1L:x
h=cA]^:=
9Xh<vh8&
,(yaWd6
java代码: ]G~u8HPH!m
j1@PfKh
{>&M:_`k
/*Created on 2005-7-15*/ Im`R2_(]
package com.adt.dao.impl; ~r]$(V n
>&qaT*_g
import java.util.List; 3A b_Z
/P{'nI
import org.flyware.util.page.Page; 0pe*DbYP5
3t ]0
import net.sf.hibernate.HibernateException; SMm$4h R
import net.sf.hibernate.Query; 3V/|" R2s
y*sqnzgF
import com.adt.dao.UserDAO; OdJ=4 x>
DVbY
/** jAFJ?L(
* @author Joa 7mS_Cz+cB
*/ 0vz!)
public class UserDAOImpl extends BaseDAOHibernateImpl ubi6=
Gc!&I+kd
implements UserDAO { }Tk*?tYt
+Kg3qS"
/* (non-Javadoc) e]d\S]5
* @see com.adt.dao.UserDAO#getUserByName k*T&>$k}^
Fo|
rRI2
(java.lang.String) Bk4|ik}
*/ O6!:Qd
publicList getUserByName(String name)throws ~\+mo
}l@7t&T|
HibernateException { Q"{Q]IT
String querySentence = "FROM user in class V_Y2 @4
g>Kh? (
com.adt.po.User WHERE user.name=:name"; cNuBWLG
Query query = getSession().createQuery '~Gk{'Nx"
ZP7wS
(querySentence); `l}r&z(8
query.setParameter("name", name); K}Pi"Le@W
return query.list(); 6~(iLtd#
} ^F$iD (f
kv3V|
/* (non-Javadoc) &uv7`VT
* @see com.adt.dao.UserDAO#getUserCount() >:U{o!N`#_
*/ 6?jSe<4x
publicint getUserCount()throws HibernateException { W#[3a4%m
int count = 0; Fm.IRu<\`
String querySentence = "SELECT count(*) FROM Z|Xv_Xo|4
`lq[6[n
user in class com.adt.po.User"; ,HO@bCK
Query query = getSession().createQuery vn=0=(
@$d_JwI
(querySentence); c:z<8#A}
count = ((Integer)query.iterate().next a{8g9a4
8U&93$
()).intValue(); `wLa.Gzj
return count; J|I&{
} y <21~g=
EY
9N{
/* (non-Javadoc) ,1-#Z"~c
* @see com.adt.dao.UserDAO#getUserByPage SSI('6Z/
B6a
(org.flyware.util.page.Page) ,!g%`@u
*/ <)9E .h
publicList getUserByPage(Page page)throws <q#/z&F!
?f[U8S}
HibernateException { O0#9D'{
String querySentence = "FROM user in class ~f>km|Q{u
FiJU
*
com.adt.po.User"; (&Z`P
Query query = getSession().createQuery })@LvYK
MDKiwT@#
(querySentence); 6P*2Kg`
query.setFirstResult(page.getBeginIndex()) ^c]lEo
.setMaxResults(page.getEveryPage()); :>otlI<0t
return query.list(); q'awV5y
} E#cZM>
.9;wJ9Bw[
} .EQ1r7
9,
k%?A=h
eMC0
)B
_-g?6q
u9%)_Q!14
至此,一个完整的分页程序完成。前台的只需要调用 }7jg>3ng(
%phv <AW
userManager.listUser(page)即可得到一个Page对象和结果集对象 Nt'u;0
5hbQUF
,Q
的综合体,而传入的参数page对象则可以由前台传入,如果用 F45UO%/P
O(QJiS
webwork,甚至可以直接在配置文件中指定。 ^iq$zHbc0u
+'!vm6
下面给出一个webwork调用示例: x,SzZ)l-9
java代码: UN*XLHio
#r_&Q`!eU
Mw+8p}E
/*Created on 2005-6-17*/ *6e 5T
package com.adt.action.user; .)eX(2j\
^d2bl,1
import java.util.List; T&`H )o
*aF<#m v
import org.apache.commons.logging.Log; Lcyj,R
import org.apache.commons.logging.LogFactory; $VCWc#
import org.flyware.util.page.Page; $w$4RQk3n
7EAkY`Op
import com.adt.bo.Result; [8QE}TFic
import com.adt.service.UserService; e:
import com.opensymphony.xwork.Action; 4^O'K;$leD
MzsDDP+h
/** F$Q@UVA
* @author Joa u*$ 1e
*/ C}{$'#DV2
publicclass ListUser implementsAction{ :2fz4n0{/
M(2c{TT
privatestaticfinal Log logger = LogFactory.getLog ;tF7GjEp
fX HNm$"n
(ListUser.class); A[6$'IJ
3%W
R
private UserService userService; L>mv\D;o.
pPdOwK#
private Page page; {s=$.Kg
Rg6e7JVu
privateList users; 'nM)=
M/,jHG8v
/* &<P!o_+eb
* (non-Javadoc) xv{iWJcs
* Wh)QCp0|n
* @see com.opensymphony.xwork.Action#execute() X>#!s Lt
*/ QxmVImn"
publicString execute()throwsException{ FFNv'\)
Result result = userService.listUser(page); |h,aV(Q
page = result.getPage(); 04wmN
users = result.getContent(); y8KJoVPiM
return SUCCESS;
C9q`x2
} ^vmyiF
o|nj2 .
/** 5[|MO.CB$
* @return Returns the page. U9KnW]O%"
*/ ,&sBa{0
public Page getPage(){ 9*%Uoy:
return page; ;,y9
} zA![c l>$
@])qw_
/** QMzBx*g(
* @return Returns the users. 10JxfDceD
*/ +x!V;H(
publicList getUsers(){ u=I>DEe@c
return users; ]~z2s;J{/
} ) tGC&l+?/
o(.
PxcD
/** JeJc(e
* @param page 7K`A2
* The page to set. L44-: 3
*/ a<[@p
publicvoid setPage(Page page){ R4"g?
e
this.page = page; 1e;^MzB"
} -,~n|ceI
(d[)U<
/** ^z$-NSlI
* @param users MS6^= ["
* The users to set. {O6f1LuH
*/ oUm"qt_
publicvoid setUsers(List users){ WZ'3
this.users = users; $+sNjwv^F
} N"b>]Ab] ;
`?Wak=]g
/** NwmO[pt+
* @param userService gUCv#:
* The userService to set. ,c6ID|\
*/ oSt-w{!
publicvoid setUserService(UserService userService){ P'Jw: )k(
this.userService = userService; !9i,V{$c`"
} :<s)QD
} +EcN[-~
Od'!v &
?0+D1w
er}/~@JJ
1dOVH7
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, 4ow)vS(
:JSOj@s
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 m5sgcxt/
9q;\;-
么只需要: @7%nMTZ@&v
java代码: POc<
G^
X LPO_tD
"!gd)^<e
<?xml version="1.0"?> L&