Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (&gCVf
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 HwGtLeB"
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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 :#L B}=HQ
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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 !uZ+r%
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分页支持类: q{@Wn]!k
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java代码: UkYQ<MNO
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package com.javaeye.common.util; "2h#inS
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import java.util.List; ZHBwoC#5}
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publicclass PaginationSupport {
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publicfinalstaticint PAGESIZE = 30; e,x@?L*
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privateint pageSize = PAGESIZE; Q,4F=b
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privateList items; mA."*)8VNg
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privateint totalCount; ::R^ w"
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privateint[] indexes = newint[0]; jn7}jWA
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privateint startIndex = 0; 646yeQ1
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public PaginationSupport(List items, int ufJFS+?
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totalCount){ CxRp$;rk
setPageSize(PAGESIZE); Q?>#sN,
setTotalCount(totalCount); wiVQMgi`
setItems(items); /X:lt^?%I
setStartIndex(0); Vy9n3W"FB1
} vW_A.iI"e
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public PaginationSupport(List items, int a_ P[J8j
! $iR:ji
totalCount, int startIndex){ Cb13 Qz
setPageSize(PAGESIZE); )_=&)a1U
setTotalCount(totalCount); oY]VP+b!
setItems(items); 7Y)wu$!7}
setStartIndex(startIndex); ,VZ&Gc
} kgI Wgk%
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public PaginationSupport(List items, int vBpg6
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totalCount, int pageSize, int startIndex){ `~RV
setPageSize(pageSize); wx!*fy4hL
setTotalCount(totalCount); V;6M[ic}
setItems(items); ~L1O\V
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setStartIndex(startIndex); <Hp"ZCN
} fH.W
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publicList getItems(){ AWi87q
return items; 1^;h:,e6
} rEf\|x=st:
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publicvoid setItems(List items){ 4Rm3'Ch
this.items = items; W>~%6K>p
} H>]z=w~
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publicint getPageSize(){ A)#sh)
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return pageSize; !$?@;}=
} KFhn}C3
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publicvoid setPageSize(int pageSize){ q!TbM"
this.pageSize = pageSize; =4D_-Q
} jysV%q 3
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publicint getTotalCount(){ -7$'* V9$
return totalCount; {q)B@#p
} JXAyF6
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publicvoid setTotalCount(int totalCount){ c-T
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if(totalCount > 0){
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this.totalCount = totalCount; >(rB[ZJ
int count = totalCount / ^;3rdBprm
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pageSize; ]aRD6F:L
if(totalCount % pageSize > 0) qWpC e*C
count++; &V3oW1*W
indexes = newint[count]; gdK/:%u3
for(int i = 0; i < count; i++){ $.1'Ym
indexes = pageSize * ZX;k*OrW
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i; }ELCnN
} :U q]~e
}else{ _e_%U<\4
this.totalCount = 0; w3N%J>4_E
} T/;hIX:R
} $te,\$&}
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publicint[] getIndexes(){ ,m?D\Pru
return indexes; b1u'ukDP\
} % 4"~O
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publicvoid setIndexes(int[] indexes){ `Cf
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this.indexes = indexes; Y/66`&,{
} \ Sby(l
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publicint getStartIndex(){ c.Y8CD.tqL
return startIndex; ;8T=uCi
} ~BZV:Es
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publicvoid setStartIndex(int startIndex){ bW^QH-t
if(totalCount <= 0) 3x0wk9lND
this.startIndex = 0; yTt (fn:;
elseif(startIndex >= totalCount) ->&VbR)
this.startIndex = indexes ~k0)+D}
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[indexes.length - 1]; S1`0d9ds#
elseif(startIndex < 0) E`n`#=xKR
this.startIndex = 0; J_|}Xd)~t6
else{ {\/nUbo[
this.startIndex = indexes ^6oqq[$
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[startIndex / pageSize]; .b`P!
} bDS1'Ce
} ^(JHRH~=h
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publicint getNextIndex(){ "EYjY->
int nextIndex = getStartIndex() + >Ro n+
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pageSize; |Du13i4].&
if(nextIndex >= totalCount) Qsxkw
return getStartIndex(); &[Zap6]
else h&M
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return nextIndex; w00\1'-Kz
} F` 5/9?;|
!# :$u=
publicint getPreviousIndex(){ RhNaYO
int previousIndex = getStartIndex() - +4g%?5'
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pageSize; d 4\E
if(previousIndex < 0) Pd "mb~
return0; d"6]?
else
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return previousIndex; N8YBu/
} j~S!!Z]
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} #K1BJ#KUt
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抽象业务类 "E|r 3cN
java代码: Ru^ ONw"
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/** L sDzV)
* Created on 2005-7-12 )g:,_ 1s)|
*/ >_aio4j}r
package com.javaeye.common.business; "]s|D@^4#b
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import java.io.Serializable; a!y,!EB+Qu
import java.util.List; /D$+b9FR<
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import org.hibernate.Criteria; 3).o"AN
import org.hibernate.HibernateException; :n4:@L<%H
import org.hibernate.Session; |] !o*7"4
import org.hibernate.criterion.DetachedCriteria; >@^yj+k
import org.hibernate.criterion.Projections; "-QRkif
import >6[ X }
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org.springframework.orm.hibernate3.HibernateCallback; n*m"L|:ff
import }K/}(zuy1Y
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org.springframework.orm.hibernate3.support.HibernateDaoS fAMD2C
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upport; rbK#a)7
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import com.javaeye.common.util.PaginationSupport; Cj !i)-
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public abstract class AbstractManager extends Wz-3?EQ
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HibernateDaoSupport { B221}t
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privateboolean cacheQueries = false; hX8gV~E=y
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privateString queryCacheRegion; fATA%eA8;
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publicvoid setCacheQueries(boolean H ZDaV&)@
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cacheQueries){ \)otu\3/
this.cacheQueries = cacheQueries; uRm _
} K=c=/`E
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publicvoid setQueryCacheRegion(String sWsG,v_
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queryCacheRegion){ A3MZxu=':3
this.queryCacheRegion = ii_|)udz
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queryCacheRegion; G9i)nWr
} $m:2&lU3
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publicvoid save(finalObject entity){ [+%d3+27
getHibernateTemplate().save(entity); {1Ju}=69
} 1 ;\]D9i
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publicvoid persist(finalObject entity){ KUp
getHibernateTemplate().save(entity); T/GgF&i3
} \)^,PA3
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publicvoid update(finalObject entity){ N)y^</Ya
getHibernateTemplate().update(entity); ~m?74^ i
} b(#"w[|
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publicvoid delete(finalObject entity){ <.r ]dCf
getHibernateTemplate().delete(entity); %tzN@
} s;B
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publicObject load(finalClass entity, [y|^P\D
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finalSerializable id){ p.rdSv(8'
return getHibernateTemplate().load mUrS&&fu8
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(entity, id); A6^p}_
} E!zd(
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publicObject get(finalClass entity, |rE!
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finalSerializable id){ Q7~'![(a
return getHibernateTemplate().get @<D'-mMt
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(entity, id); yhcNE8mkQ/
} c*x J=Gz6d
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publicList findAll(finalClass entity){ ^&+zA,aL,A
return getHibernateTemplate().find("from 7tpAZ<{
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" + entity.getName()); 3>-[B`dD(
} y|q@;*rGNa
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publicList findByNamedQuery(finalString (NH8AS<
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namedQuery){ ^M`>YOU2+
return getHibernateTemplate K1?Z5X(b
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().findByNamedQuery(namedQuery); LP^p~5Az
} VHXI@UT*
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publicList findByNamedQuery(finalString query, /=8O&1=D
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finalObject parameter){ ==%`e/~Y
return getHibernateTemplate .S~@BI(|<
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().findByNamedQuery(query, parameter); i\t753<Ys
} Ik`O.Q.}
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publicList findByNamedQuery(finalString query, 5;IT64&]
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finalObject[] parameters){ $Y8>_6%+T
return getHibernateTemplate /xl4ohL$a
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().findByNamedQuery(query, parameters); 9{_8cpm4
} b;S6'7Jf9
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publicList find(finalString query){ VZ\O9lD
return getHibernateTemplate().find ^oS$>6|
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(query); PT3>E5`N u
} =WIE>*3[
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publicList find(finalString query, finalObject J'oDOn.M
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parameter){ fv|]= e
return getHibernateTemplate().find QB!jLlg(
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(query, parameter); 'S =sj}X
} 1TKEm9j]u
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public PaginationSupport findPageByCriteria <f%ujrX
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(final DetachedCriteria detachedCriteria){ ?nQ_w0j
return findPageByCriteria ~j=xi P
+ c`AE
(detachedCriteria, PaginationSupport.PAGESIZE, 0); M2}np
} O`cdQu
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public PaginationSupport findPageByCriteria }VF#\q
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(final DetachedCriteria detachedCriteria, finalint q[-|ZA bbr
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startIndex){ N? M
return findPageByCriteria b`$yqi<[
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(detachedCriteria, PaginationSupport.PAGESIZE, d:A}CBTSY
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startIndex); NwguP
} KacR?Al
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public PaginationSupport findPageByCriteria 1j11|~
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(final DetachedCriteria detachedCriteria, finalint $H'8
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pageSize, C@1CanL@3
finalint startIndex){ Bp
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return(PaginationSupport) tE@FvZC'=
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getHibernateTemplate().execute(new HibernateCallback(){ 5UE409Gn'
publicObject doInHibernate <$%ql'=
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(Session session)throws HibernateException { :Zza)>l
Criteria criteria = UVrQV$g!
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detachedCriteria.getExecutableCriteria(session); Pg`JQC|
int totalCount = 9 CB\n
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((Integer) criteria.setProjection(Projections.rowCount '_V
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()).uniqueResult()).intValue(); tR1FO%nC
criteria.setProjection wxE?3%.j\
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(null); Wbe0ZnM]
List items = C}q>YRubZ
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criteria.setFirstResult(startIndex).setMaxResults Z^+rQ.%n"&
qe?Qeh(!X
(pageSize).list(); +Gow5-(
PaginationSupport ps = % #u.J
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new PaginationSupport(items, totalCount, pageSize, 8'_ 0g[s
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startIndex); Z0$] tS
return ps; Z0-ytODII
} &R,9+c
}, true); 1_uvoFLk
} tmO`|tn&
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public List findAllByCriteria(final ?Nf
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DetachedCriteria detachedCriteria){ {pWBwf>R C
return(List) getHibernateTemplate xST4}Mb^f
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().execute(new HibernateCallback(){ ~M5:=zKQ
publicObject doInHibernate }# Doy{T
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(Session session)throws HibernateException { <J&7]6Z
Criteria criteria = D^+?|Y@N
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detachedCriteria.getExecutableCriteria(session); z}+i=cAN
return criteria.list(); ]!Oue_-;
} Lu=O+{*8
}, true); je%l dY]/@
} UX2lPgKdLz
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public int getCountByCriteria(final y(5:}x&E
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DetachedCriteria detachedCriteria){ 'N\&<dT>
Integer count = (Integer) E)W@{?.o#
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getHibernateTemplate().execute(new HibernateCallback(){ 9 |{%i$
publicObject doInHibernate \K7t'20
Q =#I9-
(Session session)throws HibernateException { 9pLg+6O
Criteria criteria = ~jN'J+_$
eh(<m8I
detachedCriteria.getExecutableCriteria(session); sZg6@s=
return <uci9- eC
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criteria.setProjection(Projections.rowCount D//=m=
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()).uniqueResult(); &eQJfc\a
} O("Uq../3
}, true); .Q* 'r&n
return count.intValue(); gmP9j)V6
} 19t{|w<
} z)-c#F@%
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用户在web层构造查询条件detachedCriteria,和可选的 =:=/Gz1
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 d
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PaginationSupport的实例ps。 n lGHT
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ps.getItems()得到已分页好的结果集 T%IK/"N|+
ps.getIndexes()得到分页索引的数组 "& 25D
ps.getTotalCount()得到总结果数 2S~R !
ps.getStartIndex()当前分页索引 ZVih =Y-w
ps.getNextIndex()下一页索引 )OP){/
ps.getPreviousIndex()上一页索引 8e&p\%1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h6v07 7qG
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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 q7\Ovjs0
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一下代码重构了。 Yh<WA>=
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我把原本我的做法也提供出来供大家讨论吧: ;9a 6pz<
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首先,为了实现分页查询,我封装了一个Page类: %*}Y6tl '|
java代码: `yiC=$*[
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/*Created on 2005-4-14*/ 4hs)b
package org.flyware.util.page; B?bW1
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/** r!
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* @author Joa |nUl\WRd\
* %aRT>_6"
*/ }G
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publicclass Page { JRaq!/[(
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/** imply if the page has previous page */ nz]&a1"&
privateboolean hasPrePage; i)a%!1Ar
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/** imply if the page has next page */ d+eZub94U
privateboolean hasNextPage; }UwO<#
tc+WWDP#"
/** the number of every page */ I\O\,yPhhP
privateint everyPage; 3uWkc3
}<a^</s
/** the total page number */ Smw QET<H
privateint totalPage; h^UKT`9vt
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/** the number of current page */ <AH1i@4
privateint currentPage; +Vb8f["+-
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/** the begin index of the records by the current +0Q,vK#j^
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query */ \3f&7wU
privateint beginIndex; ]`g@UtD9`
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/** The default constructor */ dt@P>rel
public Page(){ 2Os1C}m
q? qC
} H,unpZ(
I#F!N6;
/** construct the page by everyPage ED>prE0
* @param everyPage tJViA`@x
* */ i:]*P
public Page(int everyPage){ /AY4M;}p
this.everyPage = everyPage; F,BOgWwP
} 'xY@ x-o
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/** The whole constructor */ w'MGA
public Page(boolean hasPrePage, boolean hasNextPage, V"\0Y0
*iBTI+"]
S-Y=-"
int everyPage, int totalPage, f5AjJYq1
int currentPage, int beginIndex){ ^zzP.
this.hasPrePage = hasPrePage;
afBE{
this.hasNextPage = hasNextPage; Ysq'2
this.everyPage = everyPage; }o4N<%/+
this.totalPage = totalPage; v{zMO:3
this.currentPage = currentPage; }/tf>?c
this.beginIndex = beginIndex; #'D"
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} 58\&/lYW
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/** TxjYrzC
* @return nRL. ppUI
* Returns the beginIndex. x+ncc_2n&D
*/ _.IxRk)T
publicint getBeginIndex(){ gI^oU4mq
return beginIndex; BS Iy+
} %,Sf1fUJ
3s\.cG?`r
/** L37 Y+C//
* @param beginIndex 0R{dNyh{
* The beginIndex to set. &,A64y
*/ ?Nf>]|K:Q
publicvoid setBeginIndex(int beginIndex){ C2LL|jp*
this.beginIndex = beginIndex; An;MVA
} 5pr"d@.
+/,icA}PI
/** @SZM82qU2z
* @return {^(ACS9mL
* Returns the currentPage. ?0?
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*/ aRG2@5
publicint getCurrentPage(){ L
pR''`2BT
return currentPage; p&+;w
} 5^']+5_vb
*.L81er5~
/** kt`nbm|aw
* @param currentPage ];.pK
* The currentPage to set. '!l1=cZD
*/ m'P1BLk
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; JJ;[,
} zi`b2h
rSXh;\MfB4
/** 'RRmIx2X
* @return -~?J+o+Pr"
* Returns the everyPage. l @^3Exwt
*/ )*4fzo
publicint getEveryPage(){ dJT]/g
return everyPage; %K(<$!
} pw7[y^[Qg
@u==x*{|
/** 'F>'(XWWQ
* @param everyPage
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* The everyPage to set. ml \4xp,
*/ G}&Sle]
publicvoid setEveryPage(int everyPage){ tOfg?)h{dc
this.everyPage = everyPage; TXe$<4"
} XsnF~)YW
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/** J[f;Xlh
* @return (`y*V;o4
* Returns the hasNextPage. bh^LIU
*/ ,-7R(iMd
publicboolean getHasNextPage(){ `PY>Hgb
return hasNextPage; [9Ss#~
} h/~n\0,J/
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/** w@N
* @param hasNextPage h;6lK$!c
* The hasNextPage to set. y|'SXM
*/ } CeCc0M
publicvoid setHasNextPage(boolean hasNextPage){ LX^u_Iu
this.hasNextPage = hasNextPage; G:zua`u[
} Me
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/** r*Yi1j/
* @return }Ho Qwy|&
* Returns the hasPrePage. >JiltF7H0
*/ sQMFpIrr
publicboolean getHasPrePage(){ ]Dw]p!@
return hasPrePage; 6/rFHY2q
} X7s
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/** &hRvol\J
* @param hasPrePage xO-+i\ ZV
* The hasPrePage to set. y~)1
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*/ aH^RoG}
publicvoid setHasPrePage(boolean hasPrePage){ &^W|iXi#
this.hasPrePage = hasPrePage; I1PuHf Qs
} xQUu|gtL4
!Q#{o^{Y~
/** lT(oL|{#P
* @return Returns the totalPage. ;3'.C~
* 8MSC.0
*/ trAkcYd
publicint getTotalPage(){ <:?r:fQX
return totalPage; OF\rgz
} L'u\w
2Lx3=[ik
/** aG^4BpIP
* @param totalPage mauI42
* The totalPage to set. k+ze74_"
*/ T<XA8h*
publicvoid setTotalPage(int totalPage){ ih7/}
this.totalPage = totalPage; \EVBwE,
} U\Z?taXB
qHxqQ'ks;
} y\a1iy
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2 $Tj84'X
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 #5f-`~^C{
M@5?ZZ4L
个PageUtil,负责对Page对象进行构造: ayiu,DXx
java代码: %mZ {4<7
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uvrB5=u
/*Created on 2005-4-14*/ t25,0<iW
package org.flyware.util.page; e d<n9R
]w.;4`l*
import org.apache.commons.logging.Log; 78/Zk}I]
import org.apache.commons.logging.LogFactory; 9]@A]p!
d+'p@!W_
/** ariLG [:X
* @author Joa nJo`B4'U
* qTqwPWW*
*/ rwI
publicclass PageUtil { 5F~'gLH/F-
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privatestaticfinal Log logger = LogFactory.getLog %HL*c=
E160A5BTx
(PageUtil.class); \Cii1\R=
}5hqDBK?
/** (2=Zm@Zpf
* Use the origin page to create a new page kO}AxeQ
* @param page +t?3T-@Ks
* @param totalRecords Xwhui4'w
* @return ( vca&wI!
*/ 9T1ZL5
publicstatic Page createPage(Page page, int u,UmrR
?#45wC
totalRecords){ 7Zh~lM
return createPage(page.getEveryPage(), |>#{[wko
O<,\^[x
page.getCurrentPage(), totalRecords); k3uit+ge}
} LbkF
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/** !7kG!)40
* the basic page utils not including exception (_"*NY0
T7#W0^tj
handler 07[_.i.l
* @param everyPage o}$EG
* @param currentPage 2* 2wY =
* @param totalRecords *"{lMZ+
* @return page C<P%CG&;
*/ q,+yqrt
publicstatic Page createPage(int everyPage, int hy`?E6=9+
;S>])5<
currentPage, int totalRecords){ (Kv#m
3~
everyPage = getEveryPage(everyPage); m8o(J\]
currentPage = getCurrentPage(currentPage); ]]*7\ :cb
int beginIndex = getBeginIndex(everyPage, D/Mi^5H)
sPR1?:0:
currentPage); MP>dW nl
int totalPage = getTotalPage(everyPage, `-p:vq`
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totalRecords); fe9LEM8j
boolean hasNextPage = hasNextPage(currentPage, [Ki0b^
-&-Ma,M?
totalPage); +>r/ 0b
boolean hasPrePage = hasPrePage(currentPage); o/+13C
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returnnew Page(hasPrePage, hasNextPage, c5u@pvSP
everyPage, totalPage, i ~{Ufi
currentPage, Ac<Phy-J
LL3#5AA"k|
beginIndex); "*Tb"
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} vuoQz\
{\:{[{qF
privatestaticint getEveryPage(int everyPage){ D>LZP!
return everyPage == 0 ? 10 : everyPage; 5.MGaU^Z$
} SgS~ {4Zx*
Mw;sLsu
privatestaticint getCurrentPage(int currentPage){ 2u5|8
return currentPage == 0 ? 1 : currentPage; HlH64w2^R
}
%*L:sTj(
G{6;>8h
privatestaticint getBeginIndex(int everyPage, int K5xX)oV
~1>.A(,=z
currentPage){ :R~MO&
return(currentPage - 1) * everyPage; k@z,Iq8
} Yj6*NZ*
njWL U!
privatestaticint getTotalPage(int everyPage, int 0Nnsjh
G1o3l~x
totalRecords){ lLF-{
int totalPage = 0; (aH'h1,G
9R7A8
if(totalRecords % everyPage == 0) z}MP)|aH:
totalPage = totalRecords / everyPage; /,g ,Ch<d
else r(RKwr:m
totalPage = totalRecords / everyPage + 1 ; 6I4oi@hZz
Bi
@2
return totalPage; @
<
Q|5
} n6BQk2l
Y\$ySvZ0
privatestaticboolean hasPrePage(int currentPage){ s=0BMPDgm
return currentPage == 1 ? false : true; XBp? w
} j'MO(ev
&3n~%$#N
privatestaticboolean hasNextPage(int currentPage, HBu[gh;b
LdL/399<
int totalPage){ Wwr;-Qa}g
return currentPage == totalPage || totalPage == w tiny,6
i:OK8Q{VI
0 ? false : true; a- |*?{o
} Y7*U:I+N
Aj+2;]M
V 7Ek-2M
} iqe%=%ZR
V4KMOYqm
V0P>YQq9s
cT!\{~
5Hw~2 ?a,
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。 F*3j.lI
p(/dBt[3k
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 'a\%L:`
.K p
做法如下: >8qQK r\"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @CZT
E: $P=%b
的信息,和一个结果集List: Lcg)UcB-#
java代码: -T[lx\}
[YUv7|\
F)'.g d
/*Created on 2005-6-13*/ 0a-0Y&lQm
package com.adt.bo; y"H*%]
/Z@tv.f
import java.util.List; UHTvCc
fngOeLVG
import org.flyware.util.page.Page; W8KDX_vGJ
4<lRPsvgc
/** Wb?8j M
* @author Joa b"vv>Q~U
*/ V;:j ZpG
publicclass Result { 98uV6b~g
-\
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private Page page; ;3B1_vo9
NqDHCI
private List content; 9.a3&*tV[
#]ypHVE
/** :n.f_v}6
* The default constructor j]aoR
*/ :uK?4
public Result(){ to=y#$_
super(); a*ushB
} {O7X`'[
%\H|B0
/** `m!j$,c.
* The constructor using fields _U
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* CkdP #}f
* @param page ^7 &5
z&o
* @param content Ipq"E
*/ uFPF!Ern
public Result(Page page, List content){ 8p@Piy{p
this.page = page; [g:$K5\64
this.content = content; jO1r)hw N>
} (tZrw5@
N#DYJ-~*
/** &'
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* @return Returns the content. e0T34x'
*/ :qIXY/
publicList getContent(){
SVB \
return content; ~,5gUl?Il
} 5[YDZ7g"~
fM^qQM[lG
/** PSZL2iGj9V
* @return Returns the page. NR5oIKP?
*/ qx4I_%
public Page getPage(){ IbP#_Vt
return page; |,!IZ-
th
} 8$;=Uf,x
]2\VweV
/** 79xx2
* @param content EodQ*{l
* The content to set. Xt@Z}B))pu
*/ cxr=k%~}J
public void setContent(List content){ INi]R^-
this.content = content; DIzH`|Y
} b+&%1C
|qmu_x\
/** gm[z[~X@
* @param page {yB&xj[z
* The page to set. aM:nOt" S1
*/ $l|qk z
publicvoid setPage(Page page){ HLZ;8/|48m
this.page = page; U~j
^I^
} 0QOBL'{7)
} W^]3XJP
'zGo?a
8@2OJ =`[
p~,]*y:XT
kAC&S!n
2. 编写业务逻辑接口,并实现它(UserManager, (r D_(%o
yGPS`S
UserManagerImpl) ^]a #7/]o
java代码: P:aJ#
.sj^{kGE
d
BJJZ^(
/*Created on 2005-7-15*/ U2wbv Xr5-
package com.adt.service; L"j
tf78
< !dqTJos
import net.sf.hibernate.HibernateException; yRfSJbzaf\
KjE+QUa
import org.flyware.util.page.Page; Y~(Md@!0S
FWHNj.r
import com.adt.bo.Result; cQ"~\
}C>{uXv
/** _oUHJ~&,
* @author Joa (Yis:%c\!
*/ qycI(5S,
publicinterface UserManager { dOoK Lry
nC}6B).el
public Result listUser(Page page)throws !gv`FE9y
X6mqi;+
HibernateException; qQsku;C?i
4@ML3d/
} frT]5?{
S&\L-@
T<w5vqFDu
v!ujj5-$I
uJ5Eka
java代码: m:WyuU<
,eZ1uBI?
QiLEL
/*Created on 2005-7-15*/ %d(^d
package com.adt.service.impl; eQD)$d_5
Y>E zTV
import java.util.List; w`il=ZAC
e*;c(3>(
import net.sf.hibernate.HibernateException; q"<ac qK
(Xq)p y9
import org.flyware.util.page.Page; )Ib<F7v
import org.flyware.util.page.PageUtil; *i- _6s
r;Gi+Ca5
import com.adt.bo.Result; 7qg{v9|,
import com.adt.dao.UserDAO; ]b%Hy
import com.adt.exception.ObjectNotFoundException; ?$6Y2
import com.adt.service.UserManager; q&/Yg,p\
NNE<L;u
/** V%YiAr>
* @author Joa 9lW;Nk*j:
*/ Yl#Rib
publicclass UserManagerImpl implements UserManager { j
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RQ'H$r.7g
private UserDAO userDAO; 'F_8j;
X(\fN[;
/** weE/TW\e
* @param userDAO The userDAO to set. <Gt2(;
*/ UF<uU-C"
publicvoid setUserDAO(UserDAO userDAO){ fe_yqIdk
this.userDAO = userDAO; $ n+w$CI)
} ;ml)l~~YU
LK, bO|
/* (non-Javadoc) Pp`*]Ib
* @see com.adt.service.UserManager#listUser bVL9vNK
3plzHz ,x
(org.flyware.util.page.Page) 'C
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*/ 8-_QFgY
public Result listUser(Page page)throws _&j}<K$-(
_`_%Y(Xat
HibernateException, ObjectNotFoundException { w -
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int totalRecords = userDAO.getUserCount(); 'eJ+JM<0%
if(totalRecords == 0) bD[!/'4eJ
throw new ObjectNotFoundException M5*{
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("userNotExist"); 7A\~)U@
page = PageUtil.createPage(page, totalRecords); #L{OV)a<
List users = userDAO.getUserByPage(page); 3'c0#h@VD
returnnew Result(page, users); N\#MwLm
} k7>|q"0C
e=Z,
Jg
} Sz^5b!
;zIP,PMM
spGB)k,^
oA =4=`
qd#sY.|1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 p"FW&Q=PN
<0QH<4
询,接下来编写UserDAO的代码: =ZDAeVz3w
3. UserDAO 和 UserDAOImpl: sm\f0P!rv
java代码: F^5?\
sp5eVAd
Tjl:|F8
/*Created on 2005-7-15*/ OnF3l Cmu
package com.adt.dao; IZ=Mlu
HE'2"t[a
import java.util.List; {iv<w8CU)
#ceaZn|@m
import org.flyware.util.page.Page; xZQg'IT
9$Xu,y
import net.sf.hibernate.HibernateException; 2Ri{bWi
/}PF\j9#4
/** 9(5OeH6o?
* @author Joa GHsilba
*/ wmTq` XH)
publicinterface UserDAO extends BaseDAO { {2+L@
e?Ho a$k
publicList getUserByName(String name)throws A%^w^f
XvE9b5}
HibernateException; QR
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/,X[k !
publicint getUserCount()throws HibernateException; *3&fqBg
Ty<L8+B|
publicList getUserByPage(Page page)throws AN24Sf'`
|6(ZD^w
HibernateException; Nof3F/2 N&
}t;(VynV)
} <6fv1d+v
* 0|IXGr
L}FOjrN
HS.^y
x
FP>)&3>_
java代码: .'rW.'Ft
S=nP[s
ecgtUb8K
/*Created on 2005-7-15*/ Cf:#(D
package com.adt.dao.impl; .%^]9/4
]miy/V }5
import java.util.List; S3@|Q\*r
TU GNq
import org.flyware.util.page.Page; hBFP1u/E'
|<Gl91
import net.sf.hibernate.HibernateException; ]ZoD'-,
import net.sf.hibernate.Query; `d[1`P1i[
*JaqTI,e
import com.adt.dao.UserDAO; Qhw^S*
.-IkL|M
/** }4{fQ`HT
* @author Joa l6~-8d+lfN
*/ b
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public class UserDAOImpl extends BaseDAOHibernateImpl 1I*7SkgKv
z9p05NFH
implements UserDAO { 3 HIz9F(
Rt{B(L.?<
/* (non-Javadoc) oh
KCdT~
* @see com.adt.dao.UserDAO#getUserByName &E40*
(C
jC3Vbm&ZZ
(java.lang.String) P{5-Mx!{&
*/ 6}(J6T46M[
publicList getUserByName(String name)throws p<&Xd}]"^W
@0eHS+
HibernateException { 4WN3=B
String querySentence = "FROM user in class dTL5-@
z OSs[[
com.adt.po.User WHERE user.name=:name"; rC7``#5
Query query = getSession().createQuery ]/!<PF
9XHz-+bQ
(querySentence); Mze;k3
query.setParameter("name", name); h@@nR(<i
return query.list(); :KKa4=5L
} 3 AHY|
|hO~X~P
/* (non-Javadoc) sT/c_^y
* @see com.adt.dao.UserDAO#getUserCount() u1~9{"P*
*/ %\kOLE2`
publicint getUserCount()throws HibernateException { &tZG
@
int count = 0; [Cb`{
String querySentence = "SELECT count(*) FROM NziZTU}
$Y9jrR'w
user in class com.adt.po.User"; -\y-qHgb/
Query query = getSession().createQuery 'Vr$MaO
o d7]tOK9
(querySentence); xESjM1A)
count = ((Integer)query.iterate().next _6k*'aT~FK
$%%os6y2v
()).intValue(); +e-,ST&w(
return count; e|rg;`AW
} WH$e2[+Y
AWjm~D-?
/* (non-Javadoc) oM)h#8bq
* @see com.adt.dao.UserDAO#getUserByPage w]_zp?\^
}
yg2uC(2
(org.flyware.util.page.Page) "GQl~
*/ 3-%Cw2ds
publicList getUserByPage(Page page)throws P1U*g!
Pe_!?:vF
HibernateException { HJC(\\~
String querySentence = "FROM user in class i,nm`Z>u
9~0^PzTA
com.adt.po.User"; ;ml
3
Query query = getSession().createQuery `T2$4 >!
j6,ZEm
(querySentence); IF +i3#$
query.setFirstResult(page.getBeginIndex()) 6ATtW+sN ]
.setMaxResults(page.getEveryPage()); Ox#Q2W@Uy
return query.list(); KT.?Xp:z
} D-U<u@A4
,=~z6[
} ai'4_
`$604+G
j.i#*tN//
BT_tOEL#
: 5U"XY x@
至此,一个完整的分页程序完成。前台的只需要调用 ;D.h65rr
GI7=xh
userManager.listUser(page)即可得到一个Page对象和结果集对象 aZk&`Jpz
y#<MVH
的综合体,而传入的参数page对象则可以由前台传入,如果用 H2r8,|XL
@-)tM.8~
webwork,甚至可以直接在配置文件中指定。 T'#!~GpB
T%F0B`
下面给出一个webwork调用示例: $ C0TD7=
java代码: =1oNZKBP
j+8TlVur
:+%Zh@u\
/*Created on 2005-6-17*/ >az;!7~cD
package com.adt.action.user; B(DrY1ztj
;XC@=RpX
import java.util.List; U{ ;l0 2S
e.o;eD}"
import org.apache.commons.logging.Log; *RR[H6B^]X
import org.apache.commons.logging.LogFactory; f&hwi:t
import org.flyware.util.page.Page; C*I(|.i@
#Y93y\
import com.adt.bo.Result; dp5f7>]:(
import com.adt.service.UserService; sLcFt1
import com.opensymphony.xwork.Action; R
4wr
+jqj6O@Tjr
/** jAND7&W
* @author Joa t=R6mjb
*/ 6S.~s6o,
publicclass ListUser implementsAction{ Hwm?#6\5
jko"MfJ
privatestaticfinal Log logger = LogFactory.getLog 2uk x (Z
7@PIM5h
(ListUser.class); [<wbbvXR
RiO="tX'
private UserService userService; gcJF`H/iNK
-@IL"U6
private Page page; [ut#:1h^
Ra3ukYG[
privateList users; !7U\J]
JeY'8B
/* ^*^/]vM
* (non-Javadoc) uO >x:*^8
* @("}]/O
V:
* @see com.opensymphony.xwork.Action#execute() !]S=z^"<
*/ -qe bQv
publicString execute()throwsException{ l
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Result result = userService.listUser(page); z}.D"
P+
page = result.getPage(); cX
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users = result.getContent(); 1Qh`6Ya f
return SUCCESS; Z0fJ9HW
} L|^o71t|
DI&MC9j(
/** ^ft]b2i
* @return Returns the page. l[/q%Ca'>
*/ fw{,bJ(U
public Page getPage(){ .h;Se
return page; >&H~nGP.
} t#<KxwhcN
hN(L@0)
/** vN{-?
* @return Returns the users. T 4|jz<iK]
*/ V+w u
publicList getUsers(){ hkW{88
return users; qSQ@p\O~
} PMKb ]y
o6?l/nJ
/** 2[dIOb4b
* @param page g]`bnZ7
* The page to set. $`vkw(;t)1
*/ y,<$X.>QO|
publicvoid setPage(Page page){ 9.0WKcwg
this.page = page; =p&sl;PsLw
} 4w{-'M.B
Yb=6C3l@
/** wk02[
* @param users E' %lxr
* The users to set. * Zd_
HJi
*/ _2jw,WKr
publicvoid setUsers(List users){ z };ZxN
this.users = users; kb|eQtH
} v3JPE])/
F$*3@Y
/** j;2<-{
* @param userService n6d^>s9J
* The userService to set. *\LyNL(
*/ Y&,rTa
publicvoid setUserService(UserService userService){ m{&w{3pQk
this.userService = userService; '; /84j-3F
} *?8RXer
} {(\(m/!Z
PZ34 *q
7Qh_8M
?mOg@) wx
#[ :w
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, M}!A]@
3cu9[~K
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 PV,"-Nv,
JIUtj7HQ
么只需要: ~tNY"{OV#
java代码:
A1Q
+0
IT1PPm
ek[kq[U9
<?xml version="1.0"?> Igjr~@#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Ky&KF0
uu>lDvR*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- (/fT]6(
)C}KR`"
1.0.dtd"> lcig7%
e}Q>\t45
<xwork> vOgLEN&]
>Zdi5')
5
<package name="user" extends="webwork- UE)fUTS
99KVtgPm
interceptors"> [EGx
l<2oklo5
<!-- The default interceptor stack name aFG3tuaKrQ
$WNG07]tU
--> m;h<"]<
<default-interceptor-ref |yAK@Hl'
9-G b"hr
name="myDefaultWebStack"/> aQmfrx
u&SZlkf6%
<action name="listUser" k2OM="Ei}
y#bK,}
class="com.adt.action.user.ListUser"> jvO3_Zt9
<param kr{)
C|$L6n>DR6
name="page.everyPage">10</param> /:Y9sz uW`
<result F;a3
l7Y8b`
name="success">/user/user_list.jsp</result> i>"dBJh]b
</action> v?%3~XoH
9>{t}Id
</package> <~O}6HQ#
c
`ud;lI
</xwork> ?{j@6,
N<"`ShCNM
%|jzEBz@
/=trj5h
1uC;$Aj6:
^5>du~d
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 "<*nZ~nE)
8;8YA1@w
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 {,F/KL^u
+',^((o
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `x4E;Wjv
|1i]L @&
|>@-grs
Q,n4i@E
`+^sW#ki
我写的一个用于分页的类,用了泛型了,hoho 4
iKR{P6
@% H8"A
java代码: 5&G
5eA
TC@bL<1
0T1ko,C!,e
package com.intokr.util; *) }
:l
bHJoEYY^
import java.util.List; m8u=u4z("
L^jaBl
/** Dh?vU~v(6
* 用于分页的类<br> W[GQ[h
* 可以用于传递查询的结果也可以用于传送查询的参数<br> _^b@>C>O
* +]_nbWL(%
* @version 0.01 u x#.:C|
* @author cheng [NZ-WU&&LP
*/ WzlS^bZ
public class Paginator<E> { -^Rb7 g-
privateint count = 0; // 总记录数 iz$FcA]
privateint p = 1; // 页编号 +
lP5XY{
privateint num = 20; // 每页的记录数 *0-v!\{
privateList<E> results = null; // 结果 [5!'ykZ
U81;7L8
/** 'X|v+?
* 结果总数 mHHzCKE ,
*/ {vLTeIxf.G
publicint getCount(){ @c0n2 Xcr
return count; -!i;7[N
} ^t`f1rGR
yV8-
publicvoid setCount(int count){ D>ojW|@}
this.count = count; D9,e3.?p
} K q/~T7Ru
Uld_X\;Q4
/** 9e-*JYF]C
* 本结果所在的页码,从1开始 v;Swo("
* ^g70AqUc
* @return Returns the pageNo. 8g.AT@ ,Q
*/ UBL(N r
publicint getP(){ IvFR <n
return p; //~POm
} 9jqO/_7R+
6aRGG+H
/** P$6W`^DZ
* if(p<=0) p=1 Mp^^!AP 9
* -g9^0V`G
* @param p mMV2h|W
*/ dFx2>6AZt
publicvoid setP(int p){ fV*}c`
if(p <= 0) Go-wAJ>
p = 1; Y+!Ouc!$
this.p = p; .4Iw=T_
} 2]2{&b u
*Ao2j;
/** /tG 5!l
* 每页记录数量 B%TXw#|
*/ P8"6"}B;T
publicint getNum(){ qbEKp HnB
return num; /3OC7!~;fM
} 7WgIhQ~
n?zbUA#
/** ? 7/W>
* if(num<1) num=1 \C!%IR
*/ G(:s-x ig6
publicvoid setNum(int num){ -l\~p4U
if(num < 1) g[m3IJzq
num = 1; -,FK{[h]ka
this.num = num; 6 #-6Bh)>4
} oSN8Xn*qr
8mk}nex
/**
T"n>h
* 获得总页数 TNyK@~#m
*/ f#'8"ff*1
publicint getPageNum(){ |sA4:Aq
return(count - 1) / num + 1; UCe,2v%
} \s.1R/TyD
rny@n^F
/** q1U&vZ3]c
* 获得本页的开始编号,为 (p-1)*num+1 i:V0fBR[>
*/ rn5"o8|
publicint getStart(){ : :F!
return(p - 1) * num + 1; 8$2l^
} kX@bv"i
K~`n}_:
/** jK\V|5k
* @return Returns the results. "}0)YRz%
*/ +R2^*
*<
publicList<E> getResults(){ a];BW)
return results; cSY2#u|v
} U(rr vNt:t
6.7`0v?,n
public void setResults(List<E> results){ f%bc64N(
this.results = results; ^;0~6uBEJr
} H @_eFlT t
4$0jz'
public String toString(){ A Oby*c
StringBuilder buff = new StringBuilder \?bwm&6+r
[ED!J~lg8
(); WpXODkQL
buff.append("{"); 66I|0_
buff.append("count:").append(count); i!CKA}",
buff.append(",p:").append(p); &_<VZS
buff.append(",nump:").append(num); OT-n\sL$
buff.append(",results:").append 2>!_B\%) H
#g@
(results); 4(` 2#
buff.append("}"); 9X
5*{f Y
return buff.toString(); a/`c ef
} skk-.9
6'RZ
} Z-N-9E
$w|o@ Ml)
:SpG&\+