Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 VWx]1\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;au*V5a%
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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 ,:)`+v<
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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 ZF6c{~D
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分页支持类: _ \D"E>oM
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java代码: ${I*nh>=
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package com.javaeye.common.util; 6cz/n8M g
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import java.util.List; <YB9Ac~}z
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publicclass PaginationSupport { "l7NWqfB
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publicfinalstaticint PAGESIZE = 30; Io n~
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privateint pageSize = PAGESIZE; X(@uw X$m
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privateList items; D`[Khs f
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privateint totalCount; DY\J[l<<
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privateint[] indexes = newint[0]; t~``md4
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privateint startIndex = 0; &c>?~-!W
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public PaginationSupport(List items, int tyh@^7
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totalCount){ :YP #
setPageSize(PAGESIZE); d\]Yk]r
setTotalCount(totalCount); ;Hmp f0$
setItems(items); L\%orLEmK
setStartIndex(0); 0.TaXbi
} @WMA }\Cc
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public PaginationSupport(List items, int "%qzj93>
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totalCount, int startIndex){ &@% $2O.3
setPageSize(PAGESIZE); Qm4o7x{q
setTotalCount(totalCount); A1"SLFY
setItems(items); x79Ha,
setStartIndex(startIndex); CyDV r
} <\ `$Jx#
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public PaginationSupport(List items, int A\fb<
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totalCount, int pageSize, int startIndex){ :Dt~e|
setPageSize(pageSize); -
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setTotalCount(totalCount); .,0b E
setItems(items); asHxL!
setStartIndex(startIndex); :,B7-kBw
} X]%itA
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publicList getItems(){ A A^{B
return items; 2ZcKK8X;7
} zK|i='XSf
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publicvoid setItems(List items){ MUnEuhXTr
this.items = items; [F!Y%Zp
} w[tmCn+
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publicint getPageSize(){ vS\Nd1~ ?
return pageSize; SAYLG
} +{<#(}
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publicvoid setPageSize(int pageSize){ ",6M)3{|c
this.pageSize = pageSize; br-]fE.be
} AN!s{7V3
:cB=SYcC%
publicint getTotalCount(){ oVFnlA
return totalCount; ;oZ)Wt
} %D$]VSP;
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publicvoid setTotalCount(int totalCount){ eET&pP3Rp
if(totalCount > 0){ vM:cWat
this.totalCount = totalCount; a=cvCf
int count = totalCount / Ar*^;/
jTO),
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pageSize; b 5yW_Ozdh
if(totalCount % pageSize > 0) hj'(*ND7z
count++; CI353-`
indexes = newint[count]; MZ+^-@X
for(int i = 0; i < count; i++){ 0}!\$"|D
indexes = pageSize * *Kdda}
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i; }\J2?Et{
} P3$Q&^?
}else{ ry9T U
this.totalCount = 0; >B]'fUt5a
} x
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} q$I:`&
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publicint[] getIndexes(){ !;?+>R)h
return indexes; %_ !bRo
} R2Zgx\VV'
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publicvoid setIndexes(int[] indexes){ S<'[%ihx
this.indexes = indexes; F~h7{@\
} .o) `m9/
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publicint getStartIndex(){ yw];P
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return startIndex; }zhGS!fO
} [w%
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publicvoid setStartIndex(int startIndex){ 8Z(Mvq]f&
if(totalCount <= 0) :q#Xq;Wp
this.startIndex = 0; :Nofp&
elseif(startIndex >= totalCount) phM>.y_
this.startIndex = indexes |*}4 m'c
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[indexes.length - 1]; L4!{h|
elseif(startIndex < 0) B95B|tU>.
this.startIndex = 0; tH-C8Qxy
else{ ,^uEYT}j
this.startIndex = indexes RzWXKBI\E]
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[startIndex / pageSize]; Ii G6<|d8H
} oYukLr
} )wT-8o
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publicint getNextIndex(){ @`gk|W3
int nextIndex = getStartIndex() + r-:Uz\gM
iof-7{+3_
pageSize; |`.([2
if(nextIndex >= totalCount) HDF|{
return getStartIndex(); l<A|d{" ]
else #{?qNl8F*J
return nextIndex; @3zg=?3
} !QvZ<5(
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publicint getPreviousIndex(){ gHo?[pS%y
int previousIndex = getStartIndex() - ;qm
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pageSize; 9jw\s P@
if(previousIndex < 0) V,cBk
return0; p,eTY[k?
else Ft&]7dT{W
return previousIndex; `\}v#2VJ
} *{L)dW+:
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} #w' kV#
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抽象业务类 NxsBX:XDn
java代码: CLUW!F
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/** oM>Z;QVRC:
* Created on 2005-7-12 )r
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*/ (jAg_$6
package com.javaeye.common.business; <$IM8Y5p+w
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import java.io.Serializable; h-`}L=
import java.util.List; ]?!mS[X
>&}%+r\
import org.hibernate.Criteria; lE4HM$p
import org.hibernate.HibernateException; _sTROd)Vh
import org.hibernate.Session; NU5.o$
import org.hibernate.criterion.DetachedCriteria; OG>}M$Ora
import org.hibernate.criterion.Projections; ,,q10iF
import toBHkiuD
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org.springframework.orm.hibernate3.HibernateCallback; 8ap%?
import 7_inJ$
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org.springframework.orm.hibernate3.support.HibernateDaoS -#N.X_F
nH[yJGZYSA
upport; pSdI/Vj'=
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import com.javaeye.common.util.PaginationSupport; ddJe=PUb
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public abstract class AbstractManager extends :%,:"
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HibernateDaoSupport { J;8IY=
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privateboolean cacheQueries = false; Y,^@P
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privateString queryCacheRegion; !xo{-@@wS
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publicvoid setCacheQueries(boolean rrik,qyv6
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cacheQueries){ B#Vz#y
this.cacheQueries = cacheQueries; r{L>
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} >I-RGW'A
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publicvoid setQueryCacheRegion(String jtW!"TOY
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queryCacheRegion){ wsI`fO^A8
this.queryCacheRegion = 5YeM%%-S
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queryCacheRegion;
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} gd`!tRcNY
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publicvoid save(finalObject entity){ +M\`#i\g>
getHibernateTemplate().save(entity); iJ1"at
} 3TeY%5iVt
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publicvoid persist(finalObject entity){ (MxQ+D\
getHibernateTemplate().save(entity); MOQ*]fV:
} v$?+MNks
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publicvoid update(finalObject entity){ 1WxK#c-)
getHibernateTemplate().update(entity); $P/~rZ@M@
} Vc\MV0lr
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publicvoid delete(finalObject entity){ W$hx,VEy`
getHibernateTemplate().delete(entity); 1\
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} Yg%I?
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publicObject load(finalClass entity, ;-~B)M_S`
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finalSerializable id){ 3no%E03p
return getHibernateTemplate().load x[~b2o
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(entity, id); gmw|H?]
} cQCSe,$ W
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publicObject get(finalClass entity, |"ls\ 7
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finalSerializable id){ %Nlt H/I
return getHibernateTemplate().get 0l )~i''
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(entity, id); 6F!+T=
} xpV|\2C
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publicList findAll(finalClass entity){ pjKWtY@=X
return getHibernateTemplate().find("from `VA"vwz
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" + entity.getName()); iVhJ t#_b
} ?+@n3]`0
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publicList findByNamedQuery(finalString ]!?;@$wx
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namedQuery){ 9-&Ttbb4)0
return getHibernateTemplate sJL&:!}V>
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().findByNamedQuery(namedQuery); EN<F# Y3E
} w'Y7IlC
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publicList findByNamedQuery(finalString query, +~m46eI
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finalObject parameter){ ?uzRhC_)!
return getHibernateTemplate sBj(Qd
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().findByNamedQuery(query, parameter); 'f!8DGix
} V,lOt4b
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publicList findByNamedQuery(finalString query, 7Wf/$vRab
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finalObject[] parameters){ \ub7`01
return getHibernateTemplate %
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().findByNamedQuery(query, parameters); k+# %DK
}
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publicList find(finalString query){ F~R;n_IJ
return getHibernateTemplate().find hgYZOwQ
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(query); sEp"D+f
} b[r8e
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publicList find(finalString query, finalObject DU0zez I9
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parameter){ "h{q#~s
return getHibernateTemplate().find kj#?whK6~
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(query, parameter); cM(:xv
} OcR$zlgs[v
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public PaginationSupport findPageByCriteria o5Dk:Bw
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(final DetachedCriteria detachedCriteria){ ~Z\8UsVN
return findPageByCriteria c,np2myd
sJB;3"~
(detachedCriteria, PaginationSupport.PAGESIZE, 0); :KQ~Cb
} Y071Y:
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public PaginationSupport findPageByCriteria u1J0$
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(final DetachedCriteria detachedCriteria, finalint .0zY}`
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startIndex){ pNG:0
return findPageByCriteria $t$ShT)
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(detachedCriteria, PaginationSupport.PAGESIZE, .[]r}[ lU
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startIndex); Z;ht
} Q- cFtu-w
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public PaginationSupport findPageByCriteria wL+s8#{
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(final DetachedCriteria detachedCriteria, finalint 9P1OP Xv*p
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pageSize, nHM~
finalint startIndex){ :(/~:^!
return(PaginationSupport) VQc_|z_s
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getHibernateTemplate().execute(new HibernateCallback(){ &PR5q7
publicObject doInHibernate rN<0
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(Session session)throws HibernateException { kKaE=H-x
Criteria criteria = Vh'P&W?[
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detachedCriteria.getExecutableCriteria(session); %|s; C
int totalCount = }n]Ng]KM`
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((Integer) criteria.setProjection(Projections.rowCount @:oXN]+
_
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()).uniqueResult()).intValue(); Xpr?Kgz
criteria.setProjection z6KCv(zvB
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(null); ,82S=N5V!
List items = A!od9W6
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criteria.setFirstResult(startIndex).setMaxResults /K+r?
]kf
rJ`!: f
(pageSize).list(); 3atBX5
PaginationSupport ps = { }:#G
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new PaginationSupport(items, totalCount, pageSize, !{ y@od@T
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startIndex); $.Qkb@}
return ps; ]&o$b ]
} JB%',J
}, true); h0(BO*cy
} fe\mL mK9
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public List findAllByCriteria(final Y4J3-wK5
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DetachedCriteria detachedCriteria){ dH;8mb|#'
return(List) getHibernateTemplate ~uj#4>3T
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().execute(new HibernateCallback(){ {kA0z2Fe
publicObject doInHibernate !44/sr'
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(Session session)throws HibernateException { S8kCp;
Criteria criteria = ]3D0R;
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detachedCriteria.getExecutableCriteria(session); AiwOc+R
return criteria.list(); tP:lP#9
} BOX{]EOj
}, true); T(#J_Y
} R}-(cc%5
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public int getCountByCriteria(final zG }@0
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DetachedCriteria detachedCriteria){ ;0Q4<F
Integer count = (Integer) DHyq^pJ
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getHibernateTemplate().execute(new HibernateCallback(){ *^\Ef4Lh
publicObject doInHibernate -z
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(Session session)throws HibernateException { TEP,Dq
Criteria criteria = ;dkYf24
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detachedCriteria.getExecutableCriteria(session); Fe# 1
return &DS/v)]
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criteria.setProjection(Projections.rowCount +G$4pt|=
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()).uniqueResult(); Ryl:a\
} "SNn^p59k
}, true); Wvq27YK'
return count.intValue(); o8 IL$:
} WO7z
} )!3V/`I
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用户在web层构造查询条件detachedCriteria,和可选的 ]vz%iv_
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 gIo@Pm
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PaginationSupport的实例ps。 ,L|%"K]yM
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ps.getItems()得到已分页好的结果集 EH-sZAv
ps.getIndexes()得到分页索引的数组 `jDTzhO~
ps.getTotalCount()得到总结果数 5^}\4.eXo
ps.getStartIndex()当前分页索引 9)D6Nm
ps.getNextIndex()下一页索引 O;+ maY^l
ps.getPreviousIndex()上一页索引 NyaQI<5D
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 i"1Mfz~e
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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 jkQ*D(;p
t^UxR@l<K|
一下代码重构了。 ud63f`W]4
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我把原本我的做法也提供出来供大家讨论吧: z$&{:\hj
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首先,为了实现分页查询,我封装了一个Page类: n|6Ic,:[
java代码: aR[JD2G
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/*Created on 2005-4-14*/ :>rkG?NfL
package org.flyware.util.page; $1SPy|y
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/** 3Lfqdqj
* @author Joa SDC4L <!
* R1s`z|?
*/ l.(v^3:X
publicclass Page { "0$a)4]
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/** imply if the page has previous page */
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privateboolean hasPrePage; biL s+\C
Z
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/** imply if the page has next page */ W1WYej"
privateboolean hasNextPage; #F:p-nOq
2kqu p)82e
/** the number of every page */ q'+)t7!
privateint everyPage; 7( #:GD
T*I{WW
/** the total page number */ ]q\b,)4
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privateint totalPage; <c*FCblv
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/** the number of current page */ n"$jG:AQJ
privateint currentPage; bAdn &
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/** the begin index of the records by the current bes<qy
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query */ oxr#7Ei0d
privateint beginIndex; yyR0]NzYUD
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/** The default constructor */ Lk|hQ
public Page(){ !zBhbmlKt
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} *$#W]bO
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/** construct the page by everyPage .Q<>-3\K
* @param everyPage "x%Htq@
* */ nz%DM<0$
public Page(int everyPage){ UJ%R
this.everyPage = everyPage; SP@ >vl+;
} pD(j'[
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/** The whole constructor */ FOb0uj=(v
public Page(boolean hasPrePage, boolean hasNextPage, c7 ?_46J
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int everyPage, int totalPage, ;i4Q|
int currentPage, int beginIndex){ S Q@y;|(
this.hasPrePage = hasPrePage; x;w6na
this.hasNextPage = hasNextPage; CJtcn_.F
this.everyPage = everyPage; .b_)%jd x
this.totalPage = totalPage; y@1+I~@
this.currentPage = currentPage; >d@&2F TO
this.beginIndex = beginIndex; uMUBh 80,L
} 9X[kEl
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/** r+' qd)
* @return w!#tTyk`
* Returns the beginIndex. 02Y]`CXj
*/ ~Cbc<[}
publicint getBeginIndex(){ AJt+p&I[J
return beginIndex; `K*Q5n
} Qd)q([
uOKCAqYa
/** zy?.u.4L
* @param beginIndex N%kt3vmQ_
* The beginIndex to set. $yN{-T"
*/ K'55O&2
publicvoid setBeginIndex(int beginIndex){ #:jHp44J
this.beginIndex = beginIndex; V4hiGO[
} Fiv3 {.
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/** {SOr#{1z*
* @return X1,I
* Returns the currentPage. GC<l#3+
*/ >~#yu&*D
publicint getCurrentPage(){ B`YTl~4
return currentPage; LU
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} #r$cyV!k
ks&*O!h
/** Ki4r<>\l{H
* @param currentPage F7A=GF'
* The currentPage to set. ZLc -RM
*/ %}[i'rT>
publicvoid setCurrentPage(int currentPage){ A mvEf
this.currentPage = currentPage; Jlri*q"hE
} 6wPaJbRtaM
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/** tW.9yII
* @return 26e]`]!SU
* Returns the everyPage. i=ea
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*/ {mm)ay|M
publicint getEveryPage(){ Bz^jw>1b
return everyPage; 5:\},n+VE
} 67VL@ ]
# Nk;4:[
/** *7:>EP
* @param everyPage Nc1"g1JR
* The everyPage to set. &@G:G(
*/ PZ2;v<
publicvoid setEveryPage(int everyPage){ E8!e:l
=Q
this.everyPage = everyPage; d.3E[AJa(
} eS{!)j_^
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/** "76]u)
* @return <W|3\p6
* Returns the hasNextPage. H6kR)~zhf
*/ 3e
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publicboolean getHasNextPage(){ +:8fC$vVfC
return hasNextPage; -mAUo;O
} k;2GEa]w
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/** -5
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* @param hasNextPage ccNd'2P
* The hasNextPage to set. |)nZ^Cc
*/ p
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publicvoid setHasNextPage(boolean hasNextPage){ 7OC#8,
this.hasNextPage = hasNextPage; W_||6LbZy
} a!ud{Dx
46$._h
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/** a<@1-j<
* @return ztnFhJ<a$
* Returns the hasPrePage. MPCBT!o4Z
*/ 2K<
8
publicboolean getHasPrePage(){ }d&_q7L@@6
return hasPrePage; VE#Wb7
} c(J!~7
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/** O|\J}rm'
* @param hasPrePage c$ao:nP)D
* The hasPrePage to set. dUsYZdQs
*/ $()5VMb
publicvoid setHasPrePage(boolean hasPrePage){ 9Kpa><
this.hasPrePage = hasPrePage; M2d$4-<
} yQU_>_!n
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/** mN~ci 0
* @return Returns the totalPage. PjZvQ\Z
* ?<V?wsp
*/ b$4"i XSQ
publicint getTotalPage(){ XnDUa3
return totalPage; 11TL~xFh
} ~kQA7;`j$
N2B|SO''
/** 'U1R\86M
* @param totalPage ADS9DiX/
* The totalPage to set. _/F7?^j
*/ Y?S!8-z
publicvoid setTotalPage(int totalPage){ %Qc La//
this.totalPage = totalPage; Hcl(3>Jn2
} K$>%e36Cc
5Ec6),+&
} {F3xJ[
prYs
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LISM ngQ.
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 JF # #
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个PageUtil,负责对Page对象进行构造: ,ek_R)&[o
java代码: D6%J\C13`
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/*Created on 2005-4-14*/ TX$r`~
package org.flyware.util.page; JM=JH
51`
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import org.apache.commons.logging.Log; MJOz.=CbhR
import org.apache.commons.logging.LogFactory; ;hYS6
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/** }M1`di4e
* @author Joa '3_]Gu-D
* |y&*MTfV4L
*/ Z8zmHc"IH
publicclass PageUtil { ]or>?{4g
cJN7bA{
privatestaticfinal Log logger = LogFactory.getLog XaCX!Lr,
{/"2Vk<H8
(PageUtil.class); -j%,Oo
&f"-d
/** {kp"nl$<
* Use the origin page to create a new page 9XPo3;
* @param page ~R_ztD+C(
* @param totalRecords lV`Q{bd+
* @return H(bs$C4F
*/ F5?m6`g?
publicstatic Page createPage(Page page, int p!>oo1&
vtw6FX_B
totalRecords){ =G]1LTI
return createPage(page.getEveryPage(), FB
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s8-<m,*
page.getCurrentPage(), totalRecords); _(Sa4Vb=Q6
} uxW~uEh
Z9MdD>uwi
/** %C$%!C
* the basic page utils not including exception kgnmGuka
?!9)q.bW
handler 3|WWo1
* @param everyPage !u_Y7i3^
* @param currentPage }lh I\q
* @param totalRecords k40* e\
* @return page (&}i`}v_
*/ qDv93
publicstatic Page createPage(int everyPage, int 9F4Dm*_<
<\Eh1[F
currentPage, int totalRecords){ 'ixwD^x
everyPage = getEveryPage(everyPage); {XNREjhm
currentPage = getCurrentPage(currentPage); hJn%mdx~w|
int beginIndex = getBeginIndex(everyPage, R<[qGt|L
:A1{ d?B
currentPage); Qy.w=80kf
int totalPage = getTotalPage(everyPage, "5-^l.CKH
V^JV4 `o
totalRecords); N
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boolean hasNextPage = hasNextPage(currentPage, S'A>2>
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totalPage); 1y-y6q
boolean hasPrePage = hasPrePage(currentPage); /4c\K-Z;
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returnnew Page(hasPrePage, hasNextPage, Fz1_w$^
everyPage, totalPage,
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currentPage, h!&prYx
{U!8|(
beginIndex); wT `a3Ymm
} Q7R~{5r>W
ZT,B(#m
privatestaticint getEveryPage(int everyPage){ vg
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return everyPage == 0 ? 10 : everyPage; j:k[90
} '`eO\huf
KMU4n-s"o
privatestaticint getCurrentPage(int currentPage){ \=uKHNP?#
return currentPage == 0 ? 1 : currentPage; "ul {d(K3
} ]3VI|f$$
<1FC%f/
privatestaticint getBeginIndex(int everyPage, int E0u~i59Z
D[^m{ 9_
currentPage){ 5!l0zLQPo
return(currentPage - 1) * everyPage; wS4.8iJ
} RT)d ]u
<z]cyXv/
privatestaticint getTotalPage(int everyPage, int J13>i7]L%
hJDi7P
totalRecords){ &$]vh
int totalPage = 0; 30XR
82P/
p$h4u_
if(totalRecords % everyPage == 0) |55N?=8
totalPage = totalRecords / everyPage; !OA]s%u
else }&n<uUD H
totalPage = totalRecords / everyPage + 1 ; BB~OqZIP
D&}3$ 7>
return totalPage; Uc_'(IyO
} Z7_m)@%;kk
"NgxkbDEbG
privatestaticboolean hasPrePage(int currentPage){ tcLnN:
return currentPage == 1 ? false : true; LXEfPLS
} &K/ya7
qjf[zF
privatestaticboolean hasNextPage(int currentPage, } w
5l
dZi(&s
int totalPage){ '[C.|)"
return currentPage == totalPage || totalPage == H2um|6>
7Garnd b
0 ? false : true; dgA-MQ5{
} JcbwDlUb
-TM0]{
Q(<)KZIK
} VJdIHsI
ZCB_
o(:[r@Z0z
"Qja1TQ
CAcS~ "
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。 "\}@gV#r$A
xER\ZpA:,
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 -[6z 1"*
*d"DA[(
做法如下: e pU:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ))&;}2{
m|=H#
的信息,和一个结果集List: 0KGY\,ae:;
java代码: (N&lHLy
,`gl&iB
1jc,
Y.mP
/*Created on 2005-6-13*/ 9G+V;0Q
package com.adt.bo; P@,nA41,j
\/1<E?Q
f
import java.util.List; Td G!&:>
Gm(b/qDDe
import org.flyware.util.page.Page; Kj<^zo%w
^}:#
/** 3'^k$;^
* @author Joa 6xZ=^;H
*/ M-[$L XR
publicclass Result { Zf'TJ`S
q-c=nkN3
private Page page; DwrO JIy
Y=?yhAw
private List content; hi0R.V&
L+CyQq
/** TZ2=O<Kj
* The default constructor Eh|]i;G%
*/ G.(mp<-
public Result(){ 6IWxPt~
super(); r=6v`)Qr
} /)dFK~
>2]JXLq
/** 'A:x/iv}^
* The constructor using fields %K>.lh@
*
F0:A]`|
* @param page 'k4E4OB
* @param content cOPB2\,
*/
"dI;
public Result(Page page, List content){ xia |+
this.page = page; ap{2$k ,
this.content = content; O9g{+e`
} :%sXO
FIbp"~
/** TpHfS]W-P
* @return Returns the content. s%2v3eb
*/ L3n_ 5|
publicList getContent(){ *&d<yJM`b
return content; (ZY@$''
} %/YcL6o(
j%y$_9a7
/** 6$ Gep
* @return Returns the page. 40|,*wi
*/ 1}tbH[
public Page getPage(){ Tp0bS
return page; 5cEcTJL[C
} Y_]De3:V0B
1!.(4gV
/** kiRa+w:
* @param content CYKr\DA
* The content to set. jiYmb8Q4D
*/ _>v<(7
public void setContent(List content){ fgBM_c&9T
this.content = content; x3u4v~ "-
} <D::9c j
n_B"-n
/** La@
+>
* @param page }sx_Yj
* The page to set. hAm`NJMSO
*/ I8QjKI (
publicvoid setPage(Page page){ l983vKr
this.page = page; %/>Y/!;
} 9JWa$iBH@
} Rcawc
Y
JXw^/Y$
~j-cS
J3
#Jna6
HmZ{L +"
2. 编写业务逻辑接口,并实现它(UserManager, uio@r^Xz
KL ?@@7
UserManagerImpl) :Dd$i_3=
java代码: +n7?S~R$
l27\diKPJ
TuW/N
L|
/*Created on 2005-7-15*/ 6:]*c[7
package com.adt.service; 06Gt&_Q
JKX_q&bUw
import net.sf.hibernate.HibernateException; w=}uwvn NX
Nr0
(E
import org.flyware.util.page.Page; 9{$'S4
HFq m6|
import com.adt.bo.Result; 4<x'ocKlD
/l{&iLz[
/** VOr 1
* @author Joa &EM\CjKv"
*/ <&!v1yR
publicinterface UserManager { 7Su#Je]
*A~
G_0B
public Result listUser(Page page)throws !sRngXCXk?
~l$3uN[g
HibernateException; IJJ%$%F/
MgC:b-&5_
} @&"Pci+-|
jM&r{^(
E( h<$w8s
TI !a )X
|TE}`?y[g
java代码: gh>>Ibf
1lsLJ4P
C_ \q?>
/*Created on 2005-7-15*/ 3&x-}y~sg
package com.adt.service.impl; af|5n><~A
]7Fs$y.
import java.util.List; NO]
3*
siTX_`0
import net.sf.hibernate.HibernateException; c,Euv>*`
vm'5s]kdh
import org.flyware.util.page.Page; @ w>zF/
import org.flyware.util.page.PageUtil; WsFk:h'r
tV9LD>3
import com.adt.bo.Result; ](B@5-^
import com.adt.dao.UserDAO; $O{duJU
import com.adt.exception.ObjectNotFoundException; s!9dQ.
import com.adt.service.UserManager; |8bq>01~
fgj^bcp-
/** '<R>E:5
* @author Joa {} Bf
*/ uHIiH@S
publicclass UserManagerImpl implements UserManager { KIeT!kmDl
5*\\J&H
private UserDAO userDAO; kSc{^-<R
^ZM0c>ev=l
/** 2S8P}$mM
* @param userDAO The userDAO to set. O,<IGO
*/ O'GG Ti]e
publicvoid setUserDAO(UserDAO userDAO){ vfB2XVc
this.userDAO = userDAO; {u[V{XIUh
} %Rh;=p`
-AYA~O(&
/* (non-Javadoc) !WkIi^T
* @see com.adt.service.UserManager#listUser 3@n>*7/E
&/A8-:m
(org.flyware.util.page.Page) 1G7b%yPA
*/ < pTTo
public Result listUser(Page page)throws 3jogD
E1&b#TE6O
HibernateException, ObjectNotFoundException { b.O9ITR
int totalRecords = userDAO.getUserCount(); J4=_w
if(totalRecords == 0) 81%8{yn!$"
throw new ObjectNotFoundException =V97;kq+v
dJ:MjQG`W
("userNotExist"); y[@\j9Hq
page = PageUtil.createPage(page, totalRecords); 93IFcmO.H@
List users = userDAO.getUserByPage(page); "7d-z<^n
returnnew Result(page, users); z^nvMTC
} NA$zd(
0lM{l?
} jxgj,h"}9`
GFk1/ F
NDO\B,7
K1?Gmue#I
-S%x
wJKM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +fKtG]$
)R_E|@"
询,接下来编写UserDAO的代码: K~RoUE<3[
3. UserDAO 和 UserDAOImpl: /?/#B `
java代码: B`$L'
+KEkmXZ
E^ hHH?w+
/*Created on 2005-7-15*/ k#}g,0@
package com.adt.dao; ?hYqcT[%
!}M,
import java.util.List; 2 }vg U$a
WqrgRpM{
import org.flyware.util.page.Page; MYe
HS
2eQdQwX
import net.sf.hibernate.HibernateException; ?y XAu0
ftk%EYT;
/** V2|3i}V"
* @author Joa 4*Z6}"
*/ _kFYBd
publicinterface UserDAO extends BaseDAO { l_/C65%.:
$!A:5jech
publicList getUserByName(String name)throws 5wC* ?>/
lo&#(L+2
HibernateException; W&"|}Pi/
.wrL3z_
publicint getUserCount()throws HibernateException; $\a5&1rl
T:asm1BC[
publicList getUserByPage(Page page)throws MVv1.6c7Y
{}>n{_
HibernateException; pN[0YmY#
IO.<q,pP!_
} /DS?}I.*]
Wx)K*9
4YU/uQm
_DPOyR2
PWgDFL?
java代码: 0m9ZQ
O
bzmr"/#D3
_'x8M
/*Created on 2005-7-15*/ ^b?2N/m@
package com.adt.dao.impl; 24\gbv<
[IM%b~j(^
import java.util.List; "L&k)J
g+zJ?
import org.flyware.util.page.Page; MN=
sIP,zk
(9fdljl],:
import net.sf.hibernate.HibernateException; a?cn9i)#
import net.sf.hibernate.Query; 5iFV;W
VFD%h
}
import com.adt.dao.UserDAO; KT*:F(4`
X}4}&
/** nw'-`*'rj
* @author Joa ~bA,GfSn0
*/ _.18z+
public class UserDAOImpl extends BaseDAOHibernateImpl iy5R5L2
w5~i^x
implements UserDAO { r;cV&T/?
t]_S
/* (non-Javadoc) 6a}r( yP
* @see com.adt.dao.UserDAO#getUserByName ,35&G"JK5
@y~P&HUN
(java.lang.String) Yig0/"
*/ P]<= ! F
publicList getUserByName(String name)throws Sg*0[a3z
0??Yr
HibernateException { 17UK1Jx,
String querySentence = "FROM user in class $. e)
%I4zQiJ%
com.adt.po.User WHERE user.name=:name"; GaNq2 G
Query query = getSession().createQuery !DjT<dxf
f_r0})
(querySentence); _ptP[SV^j
query.setParameter("name", name); u"VS* hSH
return query.list(); K!8zwb=fq
} ?p8Qx\%*
Ns~&sE:
/* (non-Javadoc) (RF>s.B<
* @see com.adt.dao.UserDAO#getUserCount() &,W$-[
*/ (7q^FtjA#
publicint getUserCount()throws HibernateException { ,I*X)(
int count = 0; +$beo2x6
String querySentence = "SELECT count(*) FROM I
,FqN}
M?6;|-HH
user in class com.adt.po.User"; s^|\9%WD
Query query = getSession().createQuery 99ASIC!
KjR4=9MD
(querySentence); whkJ pK(
count = ((Integer)query.iterate().next L=1~ f-
$-pbw@7
()).intValue(); mc@M ,2@D
return count; {K.rl%_|N
} iK}v`xq
H*U`
/* (non-Javadoc) z&'f/w8
* @see com.adt.dao.UserDAO#getUserByPage f~gSJ<t4
,Q2N[Jwd$
(org.flyware.util.page.Page) w6,*9(;$Pk
*/ 6&!l'[hU
publicList getUserByPage(Page page)throws (.^8^uc7X
-Ds|qzrN%
HibernateException { LF=c^9t
String querySentence = "FROM user in class wL
eHQ]
7!d$M{0"
com.adt.po.User"; Yw"P)Zp
Query query = getSession().createQuery el@XK}<dr
kO3`54
(querySentence); }$)&{d G
query.setFirstResult(page.getBeginIndex()) Gp1EJ2d8
.setMaxResults(page.getEveryPage()); m6so]xr
return query.list(); h(:<(o@<
} ,t~sV@ap
nP_=GI
} x0x $ 9
kEAhTh&g*
zA{8C];~
3q~Fl=|.o
@InJ_9E
至此,一个完整的分页程序完成。前台的只需要调用 KS! iL=i
O)5#Fcp(
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]gP8?s|
UH40~LxIma
的综合体,而传入的参数page对象则可以由前台传入,如果用 c^-YcGwa
{E~l>Z88
webwork,甚至可以直接在配置文件中指定。 syFI$rf
_
)fCMITq.|
下面给出一个webwork调用示例: <9 },M
java代码: F$ {4X /9n
SI_?~Pf3k
nVTM3Cz
/*Created on 2005-6-17*/ I@PJl
package com.adt.action.user; ,8`O7V{W
#:W%,$9\P
import java.util.List; A}4t9|/K6
C"No5r'K3
import org.apache.commons.logging.Log; +!$dO'0nt,
import org.apache.commons.logging.LogFactory; :@e\'~7sH
import org.flyware.util.page.Page; MgnE-6_c
w
a.f![
import com.adt.bo.Result; |uQ[W17^N
import com.adt.service.UserService; ^Jtl;Q
import com.opensymphony.xwork.Action; "`]'ZIx[R/
PN9^[X
/** Ut;'Gk
* @author Joa z@`@I
*/ U$09p;~$Ww
publicclass ListUser implementsAction{ kknhthJ
p,s&61]
privatestaticfinal Log logger = LogFactory.getLog |UZOAGiBg
|KaR
n;BM
(ListUser.class); Xoi9d1fO
[Pqn3I[
private UserService userService; -7L
!&0a<~Wi
private Page page; )8]3kQffJ=
kpT>G$s~gy
privateList users; ~9i qD
K051usm
/* ]j1
vbk
* (non-Javadoc) V
Qh/
* ,Z4^'1{D
* @see com.opensymphony.xwork.Action#execute() yI4DVu.
*/ !3?~#e{_
publicString execute()throwsException{ rBD2Si=
Result result = userService.listUser(page); cl2ze
page = result.getPage(); .r*#OUC
users = result.getContent(); >gGil|I
return SUCCESS; @:IL/o*
} |Ib.)
Y`=z.D{
/** 1!s!wQgS
* @return Returns the page. &$Ci}{{n#
*/ -PXoMZx%
public Page getPage(){ .SBc5KX
return page; jRwa0Px(
} mOSCkp{<e
mc~`
/** 8iOO1I?+
* @return Returns the users. \@:j
*/ U~hCn+0
publicList getUsers(){ pNSst_!>
return users; t@r#b67WJe
} ;6zPiaDQ
?AT(S
/** 8LeKwb
* @param page y*
rY~U#3
* The page to set. TL]bY'%
*/ Bf+^O)Ns^
publicvoid setPage(Page page){ YjL
t&D:IZ
this.page = page; W`5a:"Vg
} [Q=4P*G}X
m"q/,}DR
/** z2ds8-z
* @param users pbFYiu+
* The users to set. e-jw^
*/ CY5w$E
publicvoid setUsers(List users){ wU.'_SBfB
this.users = users; ` )]lUvR
} O68b zi]
)L|C'dJ<k`
/** 4^`PiRGt
* @param userService +{'lZa
* The userService to set. v/ eB,p
*/ Jtext%"eNg
publicvoid setUserService(UserService userService){ RpU Lm1b
this.userService = userService; 6G$/NW=L
} t+jIHo
} hO%Y{Gg
we
}#Ru*
<TL])@da
$>|?k$(x
(%Ng'~J\|
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, 1"M"h_4
y>%W;r)
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 nQ!N}5[z'
|iAEDZn
么只需要: -S`TEX
java代码: E}Ljo
*-{Omqw
B U'Ki \
<?xml version="1.0"?> &bn*p.=G
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork QaIi.*tic
>Sh0dFqeT
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;r%<2(
FF8WTuzB+
1.0.dtd"> hJ<:-u+yk}
R !jhwY$
<xwork> l'W3=,G[?
k:`a+LiZ
<package name="user" extends="webwork- 8u/3?Kc
LPb]mC6#
interceptors"> uF+);ig
m\l51}xz
<!-- The default interceptor stack name %C6|-?TAd
\f6lT3"VN
--> ,zc"udpKF
<default-interceptor-ref t`)
'LT
PnI)n=(\
name="myDefaultWebStack"/> zI1(F67d`
Z4=_k{*
<action name="listUser" N'I?fWN!;R
PQ6T|>
class="com.adt.action.user.ListUser"> 3&O% &
<param "sdcP8])d
<.;@ksCPW{
name="page.everyPage">10</param> vM5k4%D
<result :O5Tr03z
G[ ,,L
name="success">/user/user_list.jsp</result> ?Ozk^#H[
</action> Hf;RIl2F
5T7_[{
</package> WW)_Wh
5dbX%e_OP
</xwork> 6-D%)Z(
?SHc}iaU#
yjeqv-7
I|GV
:D
J11dqj
5hlJbWJa
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 kt;}]O2%R
?aP1
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。
Iz 1*4@
?psOj%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ]!n*V/g
R~U2/6V
]|H]9mys98
&z7N\n
Wh#os,U$
我写的一个用于分页的类,用了泛型了,hoho ,| $|kO/
40`9t Xn
java代码: l=Vowx.$2f
cP/F|uG5
MBnK&GS
package com.intokr.util; pE9aT5
L
Lr!L}y9T+
import java.util.List; s?4%<jz
de3yP,
/** J R8 Z6
* 用于分页的类<br> H[>klzh6
!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> %#[r_QQ^
* ;mCGh~?G
* @version 0.01 +OV%B .
* @author cheng DW'0j$;
*/ "~.8eKRQ
public class Paginator<E> { }Bv30V2-(
privateint count = 0; // 总记录数 ^EnNbFI
privateint p = 1; // 页编号 wFKuSd
privateint num = 20; // 每页的记录数 UXcH";*9b
privateList<E> results = null; // 结果 wz*)L
(pP
iKR8^sj7S
/** g_-?h&W
* 结果总数 H24ate?t,
*/ @g@fL %
publicint getCount(){ f(w#LuW<
return count; \i&vOH'
} 8u7K$Q
gPA>*;?E;@
publicvoid setCount(int count){ v@}1WGY
this.count = count; p*(U*8Q
} M ,.0[+
)'/nS$\E:
/** j\jL[hG_
* 本结果所在的页码,从1开始 s[vPH8qb
* vTe$77n
* @return Returns the pageNo. >*<6 zQf
*/ 8AC.2v?_
publicint getP(){ %_%f#S
return p; KoxGxHz^Y3
} {="Su{i}}
'p|Iwtjn>
/** oF 1W}DtA
* if(p<=0) p=1 @8 oDy$j
* gKm@B{rC
* @param p vUodp#s
*/ O9Jx%tolF%
publicvoid setP(int p){ ~%8Q75tn.
if(p <= 0) _k"&EW{ Ii
p = 1; qCxD{-9x{
this.p = p; % RBI\tj
} 2f}K#i8
)Yy#`t
/** ,_5YaX:<4
* 每页记录数量 ZmYSi$B
*/ {m*V/tX
publicint getNum(){ :!Y?j{sGU
return num; !?us[f=g%
} `K@df<}%*,
tehI!->l
/** F'Y2f6B
* if(num<1) num=1 `lV
*/ mV!
@oNCK
publicvoid setNum(int num){ ~T p8>bmSR
if(num < 1) f>"!-3
num = 1; :<WQ;q
this.num = num; I!soV0VU]
} b[&,%Sm+6
BC$;b>IUA
/** 08d_DCR
* 获得总页数 "`$'tk[
*/ 7/U<\(V!g
publicint getPageNum(){ #<PA-
y
return(count - 1) / num + 1; 35N/v G0
} 7KSGG1ts
zw%n!wc_\
/** #)h
~.D{
* 获得本页的开始编号,为 (p-1)*num+1 HN~v&,
*/ kUaGok?
publicint getStart(){ _ \y0 mc4
return(p - 1) * num + 1; !>Qc2&ZV
} vxilQp
L->f=
8L
/** 6E\\`FE4y
* @return Returns the results. _c(C;s3o
*/ h<^:Nn
publicList<E> getResults(){ U<,Kw6K
return results; ,Q /nS$
} ~&j`9jdOj
?3"D|
cS1
public void setResults(List<E> results){ ~b6<uRnM.
this.results = results; ,p/b$d1p
} Y+_5"LV
7N59B z
public String toString(){ dD.d?rnZq7
StringBuilder buff = new StringBuilder uZiY<(X
gt t$O
();
UA!Gr3
buff.append("{"); j~L1~@
buff.append("count:").append(count); %[\Ft
buff.append(",p:").append(p); !qw=I(
buff.append(",nump:").append(num); ~q_+;W.
buff.append(",results:").append &6^W%r
`d|bH;w
(results); :kiO
buff.append("}"); 64\5v?C
return buff.toString(); :@@A
} 1-NX>E5
dj'8x48H2W
} nwZr3r
)Y,?r[4{
iZq@W3GL
C