Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 w$`u_P|@E:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &VxK
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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 )5TX3#=;(G
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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 nTsPX Tat
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分页支持类: &WdP=E"
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java代码: ! &V,+}>)
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package com.javaeye.common.util; ?hW(5]p|
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import java.util.List; Lya?b
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publicclass PaginationSupport { 5d|+ c<
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publicfinalstaticint PAGESIZE = 30; `~@}f"c`u
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privateint pageSize = PAGESIZE; qt%/0
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privateList items; UL" <V
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privateint totalCount; 1'5!")r
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privateint[] indexes = newint[0]; +7K]5p;!~
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privateint startIndex = 0; cr{dl\Na
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public PaginationSupport(List items, int 2aQ}|
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totalCount){ !" : arK
setPageSize(PAGESIZE); *c@]c~hY,
setTotalCount(totalCount); &J=x[{R
setItems(items); S*rc XG6Q^
setStartIndex(0); t*Wxvoxk
} gOk^("@
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public PaginationSupport(List items, int q5w)i
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totalCount, int startIndex){ q{.~=~
setPageSize(PAGESIZE); %;G!gJeE
setTotalCount(totalCount); 2K'}Vm+
setItems(items); ^[zF IO
setStartIndex(startIndex); l1RFn,Tzr
} {K2F(kz?T
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public PaginationSupport(List items, int Vs[!WJ
7
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totalCount, int pageSize, int startIndex){ JDC,]
setPageSize(pageSize); 5TdI
setTotalCount(totalCount); c>Ljv('bj
setItems(items); ~#[ ZuMO?
setStartIndex(startIndex); to 3i!b
} yM34G S=,J
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publicList getItems(){ @aGS~^Uh
return items; j!
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} wmPpE_{
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publicvoid setItems(List items){ k<S!|
this.items = items; @i:_JOl
} VAR/"
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publicint getPageSize(){ FdJC@Y-#uA
return pageSize; "i*Gi
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} k4 %> F
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publicvoid setPageSize(int pageSize){ RwwX;I"o%
this.pageSize = pageSize; :Zd# }P
} ^SRa!8z$W
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publicint getTotalCount(){ E0S[TEDa]
return totalCount; sw &sF
} l@YpgyqaL
#$%gs]
publicvoid setTotalCount(int totalCount){ 9/|i.2&
if(totalCount > 0){ I!Za2?
this.totalCount = totalCount; `P4qEsZE>`
int count = totalCount / VVje|T^{Z
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pageSize; |wj/lX7y
if(totalCount % pageSize > 0) egi?Qg
count++; 2jx+q
indexes = newint[count]; z95V 7E
for(int i = 0; i < count; i++){ OiY2l;68
indexes = pageSize * ArU>./)Q
cw <DM%p
i; \>/:@4oK
} @kwD$%*0
}else{ /ADxHw`k
this.totalCount = 0; h?YjG^'9
} Bv@m)$9\+3
} ^! ZjK-$A<
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publicint[] getIndexes(){ Ef `LBAfOO
return indexes; (\/HGxv
} 0XYO2k
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publicvoid setIndexes(int[] indexes){ -;`W"&`ss
this.indexes = indexes; fZ g*@RR
} Em"X5>;4
fp![Pbms.
publicint getStartIndex(){ 4!}fCP ty
return startIndex; wD,F=O
} ycAQPz}=I
};!c]/,
publicvoid setStartIndex(int startIndex){ c\b>4 &n
if(totalCount <= 0) xBG1up<z
this.startIndex = 0; !3&vgvr
elseif(startIndex >= totalCount) .CpF0
this.startIndex = indexes 6Rf5
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[indexes.length - 1]; anwn!Eqk"
elseif(startIndex < 0) !aEp88u
this.startIndex = 0; BmJ?VJ}Y
else{ 8say"Qz
this.startIndex = indexes H= y-Y_R
&4[iC/}
[startIndex / pageSize]; :ZIcWIV-
} -/qrEKQ0U?
} 3U`.:w`
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publicint getNextIndex(){ Mvh_>-i
int nextIndex = getStartIndex() + <FK><aA_i*
,i,=LGn
pageSize; Z7/dRc
if(nextIndex >= totalCount) o%5bg(
return getStartIndex(); .2P?1HpK
else i=a LC*@
return nextIndex; )pLq^j
} 1m)/_y~1
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publicint getPreviousIndex(){ $g};u[y
int previousIndex = getStartIndex() - %E\%nTV
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pageSize; I@ k8^
if(previousIndex < 0) t_rDXhM
return0; kI'A`
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else 9gg,Dy
return previousIndex; hI8C XG
} Q2NnpsA^6
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} Fc~w`~tv
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抽象业务类 36a~!
java代码: o
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/** e}[we:
* Created on 2005-7-12 }Xi#x*-D
*/ P{!:pxu[
package com.javaeye.common.business; 1>VS/H`
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import java.io.Serializable; 0s""%MhFI
import java.util.List; wPJRp]FA
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import org.hibernate.Criteria; EE6|9K>
import org.hibernate.HibernateException; 7$W;4!BN*
import org.hibernate.Session; XFTMT'9
import org.hibernate.criterion.DetachedCriteria; ('q vYQ
import org.hibernate.criterion.Projections; 4E\ntufo
import (iOCzZ6S
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org.springframework.orm.hibernate3.HibernateCallback; Cw&D}
import F ssEs!#
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org.springframework.orm.hibernate3.support.HibernateDaoS ,Kf8T9z`
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upport; ^;$a_$|
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import com.javaeye.common.util.PaginationSupport; Y\e]2
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public abstract class AbstractManager extends ~po%GoH(K
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HibernateDaoSupport { M:Y*Tb6w
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privateboolean cacheQueries = false; rgdQR^!l6
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privateString queryCacheRegion; @" 0tW:
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publicvoid setCacheQueries(boolean 2Uv3_i<
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cacheQueries){ RmWfV
this.cacheQueries = cacheQueries;
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} *e3L4 7"G
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publicvoid setQueryCacheRegion(String ,+/9K)X
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queryCacheRegion){ Q6.*"`
this.queryCacheRegion = `[@^m5?b-
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queryCacheRegion; ,.oa,sku
} o'^;tLs15
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publicvoid save(finalObject entity){ 6mBDd>`0
getHibernateTemplate().save(entity); nR o=J5tY
} X"k^89y$
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publicvoid persist(finalObject entity){ ?UZ$bz
getHibernateTemplate().save(entity); s`#ntset0
} 4\1wyN /}M
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publicvoid update(finalObject entity){ DhWWN>I
getHibernateTemplate().update(entity); &$m=^
} J&63Z
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publicvoid delete(finalObject entity){ x[PEn
getHibernateTemplate().delete(entity); q8?=*1g
} gHvW
e
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publicObject load(finalClass entity, x/%7%_+'
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finalSerializable id){ ]{|fYt_-
return getHibernateTemplate().load "u<jbD
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(entity, id); P?q
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} V;iL[
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publicObject get(finalClass entity, 0
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finalSerializable id){ ZI58XS+
return getHibernateTemplate().get Ql~#((K
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(entity, id); :3a&Pb*PL
} n2n00%Wu[
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publicList findAll(finalClass entity){ S)"##-~`T
return getHibernateTemplate().find("from YKP=0 j3,
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" + entity.getName()); ,VKQRmd
} 0 W~.WkD
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publicList findByNamedQuery(finalString 0rk u4T
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namedQuery){ ;JOD!|
return getHibernateTemplate "H5&3sF2
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().findByNamedQuery(namedQuery); |`w$|pm=
} cs K>iN
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publicList findByNamedQuery(finalString query, EkRdpiLB
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finalObject parameter){ [#7y[<.P
return getHibernateTemplate T$H2'tK|
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().findByNamedQuery(query, parameter); [zY!'cz?
} YO)')&
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publicList findByNamedQuery(finalString query, r~)VGdB+
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finalObject[] parameters){ n<{aPLQ
return getHibernateTemplate M} O[`Fx{W
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().findByNamedQuery(query, parameters); _kh>Z
} clHM8$
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publicList find(finalString query){ j,}4TDWa
return getHibernateTemplate().find h=hoV5d@
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(query); >[K0=nA
} ?^U c=
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publicList find(finalString query, finalObject e d_m +NM
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parameter){ B9wp*:.
return getHibernateTemplate().find HH7[tGF
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(query, parameter); ?;Un#6b
} o5>/}wIf
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public PaginationSupport findPageByCriteria 0X.TF
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(final DetachedCriteria detachedCriteria){ EVG"._I@
return findPageByCriteria j13riI3A
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6zuze0ud
} 9MT3T?IS
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public PaginationSupport findPageByCriteria 2@fa
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(final DetachedCriteria detachedCriteria, finalint ikr7DBLt
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startIndex){ Uh*@BmDA
return findPageByCriteria {f-XyF1`
)PwQ^||{
(detachedCriteria, PaginationSupport.PAGESIZE, J8J!#j.
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startIndex); PzLJ/QER
} YN/u9[=`
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public PaginationSupport findPageByCriteria q4)Ey
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(final DetachedCriteria detachedCriteria, finalint %w$mSG
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pageSize, E.9^&E}PG
finalint startIndex){ cg{Gc]'1#
return(PaginationSupport) @/LiR>,
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getHibernateTemplate().execute(new HibernateCallback(){ l/M[am
publicObject doInHibernate 5E`JD
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(Session session)throws HibernateException { .wD>Gs{sH[
Criteria criteria = !x8kB
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detachedCriteria.getExecutableCriteria(session); {gw[%[ZM
int totalCount = bH,M,xIL2
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((Integer) criteria.setProjection(Projections.rowCount _\UIc;3Gl
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()).uniqueResult()).intValue(); %P;[fJ
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criteria.setProjection BtzYA"
jccOsG9;_
(null); 6P^hN%0
List items = ^\T]r<rCY
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criteria.setFirstResult(startIndex).setMaxResults me:iQ.g
L ?Cjo4xS
(pageSize).list(); h"r!q[MNo
PaginationSupport ps = >9MS"t
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new PaginationSupport(items, totalCount, pageSize, (7~%B"
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startIndex); G1/Gq.<
return ps; Fo(y7$33*
} uRpBeH]Z"
}, true); S2Vx e@b)
} F)7j@h^
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public List findAllByCriteria(final ##GY<\",;
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DetachedCriteria detachedCriteria){ c})wD+1
return(List) getHibernateTemplate u-:MVEm
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().execute(new HibernateCallback(){ 3e *-\TP-
publicObject doInHibernate T0Q51Q
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(Session session)throws HibernateException { 1fR P1
Criteria criteria = `,P
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detachedCriteria.getExecutableCriteria(session); DN<M?u]
return criteria.list(); }jiK3?e
} *Dc@CmBr
}, true); %I0}4$
} wV>c" J
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public int getCountByCriteria(final (0}j]p'w
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DetachedCriteria detachedCriteria){ 0qR$J
Integer count = (Integer) D J_DonO]
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getHibernateTemplate().execute(new HibernateCallback(){ OpUA{P
publicObject doInHibernate $
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(Session session)throws HibernateException { {=iyK/Uf
Criteria criteria = uJ8x
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detachedCriteria.getExecutableCriteria(session); &F`L}#oL&
return 61>f(?s
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criteria.setProjection(Projections.rowCount O5OXw]
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()).uniqueResult(); WGMb8 /{$P
} /ao<A\KR
}, true); ZPvf-PqJl
return count.intValue(); {G%3*=?,j
} K:a3+k d
} $P;UoqG<&
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用户在web层构造查询条件detachedCriteria,和可选的 'e85s%ru
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -%i#j>
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PaginationSupport的实例ps。 C]Q>*=r
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ps.getItems()得到已分页好的结果集 Uuz?8/w}#
ps.getIndexes()得到分页索引的数组 -f 4>MG
ps.getTotalCount()得到总结果数 F+3!uWUK
ps.getStartIndex()当前分页索引 gwJ}]Tf
ps.getNextIndex()下一页索引 d EIa=e|
ps.getPreviousIndex()上一页索引 K-6p'|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 T\fudmj&
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 8F)=n \
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一下代码重构了。 ?uig04@3
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我把原本我的做法也提供出来供大家讨论吧: ET3,9+Gj
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首先,为了实现分页查询,我封装了一个Page类: /cYk+c
java代码: F@EZ;[
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/*Created on 2005-4-14*/ F "!`X#
package org.flyware.util.page; RPY6Wh|4
umryA{Ps
/** f}%sO
* @author Joa H(?e&Qkg
* H6{Rd+\Z
*/ QY=QQG
publicclass Page { ^(J-dK
Cc*|Zw
/** imply if the page has previous page */ .01TTK *
privateboolean hasPrePage; .T{U^0 )
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/** imply if the page has next page */ =/m}rcDN
privateboolean hasNextPage; PYaOH_X.
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/** the number of every page */ OoSa95#x
privateint everyPage; *5^ze+:
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/** the total page number */ Fos1WH?\
privateint totalPage; 1&} G+y
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/** the number of current page */ 'h k @>"
privateint currentPage; .C6gl]6y@
9 #:ue@)
/** the begin index of the records by the current 9a-]T=5Ee
S`4e@Z$
query */ nE4l0[_
privateint beginIndex; vRxL&8`&
4">84,-N
IG>>j}
/** The default constructor */ ^T=5zqRD
public Page(){ bnIf}ut-G
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} gl Li
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/** construct the page by everyPage } cRi
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* @param everyPage 7@3M]5:3g
* */ !SN6
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public Page(int everyPage){ m[{nm95QZ
this.everyPage = everyPage; %N!h38N2
} JW2W>6Dgv[
.ZM]%[4
/** The whole constructor */ U24V55ZnI
public Page(boolean hasPrePage, boolean hasNextPage, V.+DP
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int everyPage, int totalPage, cS+?s=d
int currentPage, int beginIndex){ v#w4{.8)
this.hasPrePage = hasPrePage; PVS\,
this.hasNextPage = hasNextPage; |I4D(#w.
this.everyPage = everyPage; v!iWzN
this.totalPage = totalPage; A-}PpH~.Z
this.currentPage = currentPage; A=y24m
this.beginIndex = beginIndex; *pmoLiuB>
} 9.^-us1
U. NeK{
/** MI?]8+l
* @return qEPf-O:lm
* Returns the beginIndex. A5`#Ot*3
*/ l[:^TfB
publicint getBeginIndex(){ jD$;q7fB
return beginIndex; 4c~*hMry
} 1V#B]x:
rAtai}Lx
/** w}fqs/)w
* @param beginIndex "~B~{ _<j
* The beginIndex to set. \z<ws&z3`$
*/ }Z<D^Z~w
publicvoid setBeginIndex(int beginIndex){ r@\,VD6J
this.beginIndex = beginIndex; g4?Q.'dZr
} mOABZ#+Fk
A632 :V
/** a>#d=.
* @return jqV)V> M.
* Returns the currentPage. ] `b<"
*/ qQ3]E][/
publicint getCurrentPage(){ g9RzzE!
return currentPage; ufHuI*
} ot&j HS'
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/** 9J't[(
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* @param currentPage qen44;\L
* The currentPage to set. WMt&8W5
*/ ~7F EY0 /
publicvoid setCurrentPage(int currentPage){ P*?d6v,r
this.currentPage = currentPage; T9&,v<f
} qJe&jLZa
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/** HPv&vdr3
* @return %`t]FV^#
* Returns the everyPage. *rujdQf
*/ i!/h3%=
publicint getEveryPage(){ I_R5\l}O+D
return everyPage; TZvBcNi
} &z{dr~
~)oWSo5ll
/** RBMMXJj
* @param everyPage -;W\f<q]
* The everyPage to set. G~Q*:m
*/ 3M`hn4)K
publicvoid setEveryPage(int everyPage){ uaZ"x&oZ#
this.everyPage = everyPage; :~qtvs;{
} Y,<WX
v
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/** |1\dCE03}
* @return +3~Gc<OO
* Returns the hasNextPage. giA~+m~fN
*/ Z`0r]V`Ys
publicboolean getHasNextPage(){ 3\+[38 _
return hasNextPage; VdjU2d
} ;'Z,[ a
Q9Xmb2LN
/** ]e#,\})Br
* @param hasNextPage 6w:g77SH)%
* The hasNextPage to set. -Lz1#S k]A
*/ Z]1z*dv
publicvoid setHasNextPage(boolean hasNextPage){ A1=$kzw{UH
this.hasNextPage = hasNextPage; [xp~@5r'
} !$ J)
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/** ps{&WT3a
* @return PEwW*4Xo
* Returns the hasPrePage. t6H2tP\AS
*/ ^|a&%wxA
publicboolean getHasPrePage(){ _z_3%N
return hasPrePage; s`$_
} z?IY3]v*z<
qU
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/** O
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* @param hasPrePage i &SBW0)
* The hasPrePage to set. JXZ:Wg
*/ Cx1Sh#9
publicvoid setHasPrePage(boolean hasPrePage){ %3@RZe
this.hasPrePage = hasPrePage; cE_Xo.:Y,
} :Z7"c`6L!~
x"h)"Y[c5
/** ~$TE
* @return Returns the totalPage. gw}7%U`T9
* zN729wK
*/ ^0BF2&Zx
publicint getTotalPage(){ jT wM<?
return totalPage; L;(3u'
} <|>:UGAR
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/** aS1P]&
* @param totalPage >x _:=%Wr+
* The totalPage to set. G3^n_]Jb
*/ .ON$vn7
publicvoid setTotalPage(int totalPage){ ;MdK3c
this.totalPage = totalPage; Ow&'sR'CX
} Y;I(6`,Y
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} w!GU~0~3[
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%]= 'Uv^x
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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 R~seUW7uv"
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个PageUtil,负责对Page对象进行构造: H&>>]DD
java代码: ;wYwiSVd
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#D*J5k>2
/*Created on 2005-4-14*/ f^yLwRUD
package org.flyware.util.page; YQ[&h
N6 }i>";_;
import org.apache.commons.logging.Log; kI1{>vYD
import org.apache.commons.logging.LogFactory;
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/** ^Ihdq89 t
* @author Joa @0@'6J04
* "=5vgg3
*/ PTV`=vtj
publicclass PageUtil { [2fiHE
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privatestaticfinal Log logger = LogFactory.getLog #lVl?F+~
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(PageUtil.class); @OL3&R
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/** ]C:If h~
* Use the origin page to create a new page 0R!}}*Ee>q
* @param page KL_}:O68
* @param totalRecords /n 3&e
* @return @snLE?g j
*/ x`|tT%q@l
publicstatic Page createPage(Page page, int ]e3}9.
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totalRecords){ 0 Ukl#6
return createPage(page.getEveryPage(), W&re;?Z{ke
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page.getCurrentPage(), totalRecords); X72X:"
} -H]f@|AOw
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/** @IKe<{w
* the basic page utils not including exception LkbvA
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handler N)I
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* @param everyPage PHL@1K{)
* @param currentPage xTawG?"D
* @param totalRecords M>z7H"jCu
* @return page aiX;D/t?
*/ r`"#c7)
publicstatic Page createPage(int everyPage, int S/:QVs
e ~,'|~
C5
currentPage, int totalRecords){ eJ\j{-
everyPage = getEveryPage(everyPage); &^D@(m7>{K
currentPage = getCurrentPage(currentPage); ~E|V{z%
int beginIndex = getBeginIndex(everyPage, G78j$
^/0
%_=R&m'n`
currentPage); U=#ylQ
int totalPage = getTotalPage(everyPage, Z1lF[d,f;
U$JIF/MO_
totalRecords); WsDe0F
boolean hasNextPage = hasNextPage(currentPage, >\x
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totalPage); < 3+&DV-<N
boolean hasPrePage = hasPrePage(currentPage); h}<ZZ
5Cyjq0+
returnnew Page(hasPrePage, hasNextPage, t4c#' y
everyPage, totalPage, imq(3?
currentPage, J#Ehx|
bvRGTOxO
beginIndex); >"{zrwNq
} YqCK#zT/
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privatestaticint getEveryPage(int everyPage){ +rO<'H:umJ
return everyPage == 0 ? 10 : everyPage; 4'[ V'c\
} uiEA=*axp
cZT.vA#
privatestaticint getCurrentPage(int currentPage){ l5nDt$Ex
return currentPage == 0 ? 1 : currentPage; 05LQh
} [)0 k}
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privatestaticint getBeginIndex(int everyPage, int wupD
2 3w{h d
currentPage){ cW^)$>A
return(currentPage - 1) * everyPage; i1Sc/
} 17 iq
JJ3JULL2
privatestaticint getTotalPage(int everyPage, int MFsy`aiS
A+E@OO w*~
totalRecords){ 5&Kn #
int totalPage = 0; ho$%7mc
GQBN-Qv
if(totalRecords % everyPage == 0) jz:c)C&/
totalPage = totalRecords / everyPage; ,T[
+omo
else 8J U~Q
totalPage = totalRecords / everyPage + 1 ; ?t P/VL
RYaofW
return totalPage; ]7
mSM
} ~,-O
=_6h{f&Q
privatestaticboolean hasPrePage(int currentPage){ rM.<Gi05Qe
return currentPage == 1 ? false : true; cHct|Z
u
} )Dpt<}}\
^{bEq\5&
privatestaticboolean hasNextPage(int currentPage, [
[CXMbD`*
o_m.MMEU
int totalPage){ g$LwXfg
return currentPage == totalPage || totalPage == &J M;jSz
}Cg~::,"
0 ? false : true; N0hU~| /
} )B4c;O4t
=nZd"t'p|
>g2.z>
} JAlsc]XtO9
Bz~h-
s\R?@
t+q`h3
uelTsn
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 PaJwM%s)L
P9wDTZ
:4
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 1=.kH[R
EBLoRW=8ld
做法如下: k@U`?7X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 S`KCVQ>V
nP31jm+A
的信息,和一个结果集List: 6<nO2 GW
java代码: zxdO3I
z(eAwmuli
fTgN2U
/*Created on 2005-6-13*/ tn1aH
+
package com.adt.bo; >FNt*tX<0
oFp&j@`k8j
import java.util.List; 4iW2hV@m
/d'u1FnA=
import org.flyware.util.page.Page; :[3\jLrc
4/|=0TC;
/** t57b)5{FM
* @author Joa +Z*%,m=N(
*/ ZeZwzH)BD
publicclass Result { 5yI D%
)I4t l/
private Page page; h6t>yC\
FoQk
private List content; rg~CF<
B"v=Fr[
/** LAeX e!y
* The default constructor T-TH.
R
*/ tS7u#YMh
public Result(){ :ux`*,zh
super(); !TFVBK
} 9iE66N>z
,+&j/0U
/** *gn*S3Is[j
* The constructor using fields Apn#o2
* ,R+u%bmn#
* @param page ~7
TzUb
* @param content Tx(R3B+u7
*/ ?H&p zY~H
public Result(Page page, List content){ vkK+
C~"
this.page = page; _c2#
this.content = content; (Wn'.|^%
} 5z_)
(EX
/** rxARJso
* @return Returns the content. v|GvN|_|
*/ sq_:U_tJ
publicList getContent(){
CvN~
return content; _*9Zp1r
} Gm.hBNgp
Z=|@76
/** &BgaFx**
* @return Returns the page. L*z;-,
*/ VsC]z,
oV
public Page getPage(){ DQ)SMqOotw
return page; yrjm0BM#
} ;%1^k/b6t
.<.qRq-
/** pqe**`z@y
* @param content TO.NCO\x
* The content to set. I9E@2[=!
*/ 0`W~2ai
public void setContent(List content){ ?,j:Y0l.L
this.content = content; B:4u2/!5
} [Z0e$
.\VjS^o&Z&
/**
51j
* @param page bbJa,}R
* The page to set. ( ;"ICk&
*/ ?vVkZsU
publicvoid setPage(Page page){ ,"'agg:St
this.page = page; 6]Jv3Re'(I
} "#7i-?=
} ;Y"J j
Ol? 2Qy.2)
.#n?^73
?]t8$^m,;
V/Q6v
YX
2. 编写业务逻辑接口,并实现它(UserManager, /a
q%l]hQ@
H)S3/%.|
UserManagerImpl) (/Ubw4unI
java代码: c:0$
Mw=
AKpux,@xB
a-3~HH
/*Created on 2005-7-15*/ 1$^{Uma
package com.adt.service; )"1D-Bc\Q
BjH(E'K[b
import net.sf.hibernate.HibernateException; I$Z"o9"
iJYr?3nw;
import org.flyware.util.page.Page; DirWe
,
?%`Ky/
import com.adt.bo.Result; alG}Aw#gS
68y.yX[
/** NlKnMgt~
* @author Joa 8]Pf:_e,+
*/ u&qdrKx
publicinterface UserManager { S2*:]pYf}
gs!{'=4wT
public Result listUser(Page page)throws iz'8P-]K>
{*|yU"
HibernateException; `mMD e
_])1P?.
} +|}~6`
K9*K4'#R
34oC285yc
,^+3AT
ss[8d%V
java代码: 9@h>_1RJz
C}!$'C|
S"Efp/-
/*Created on 2005-7-15*/ A.y$.(
package com.adt.service.impl; Y)uNzb6R
1D*eu
import java.util.List; [X-Q{c4
'aCnj8B
import net.sf.hibernate.HibernateException; %o?fE4o'
A1:Fe9q
import org.flyware.util.page.Page; I($u
L@$
import org.flyware.util.page.PageUtil; lFB Ka
,6
Qc3!FW<26
import com.adt.bo.Result; 0xPML}|V
import com.adt.dao.UserDAO; Db2G)63
import com.adt.exception.ObjectNotFoundException; =^{^KHzIl3
import com.adt.service.UserManager; _z}d yp"I
&;y(@e}D
/** 4gYP .h:,
* @author Joa I\[*vgjm3G
*/ vbSz&+52;
publicclass UserManagerImpl implements UserManager { >z(6ADq
fxc~5~$>
private UserDAO userDAO; <
*XC`Ii
|5O%@
/** wi9fYfuv3R
* @param userDAO The userDAO to set. ;B7>/q;g
*/ Y(&phv&
publicvoid setUserDAO(UserDAO userDAO){ p>MX}^6
this.userDAO = userDAO; !D
} 'dx4L }d
H\O|Y@uVr
/* (non-Javadoc) 1XSqgr"3
* @see com.adt.service.UserManager#listUser |C5i3?
!x,3k\M
(org.flyware.util.page.Page) AKS(WNGEp
*/ -5E<BmM
public Result listUser(Page page)throws FMR0?\jnT
E P<U:F
HibernateException, ObjectNotFoundException { :\.v\.wm
int totalRecords = userDAO.getUserCount(); \f+R!
if(totalRecords == 0) (Q\w4?ci
throw new ObjectNotFoundException .d.7D ]Yn
1z8.wdWJ}
("userNotExist"); M14pg0Q
page = PageUtil.createPage(page, totalRecords); a5&wS@)
;
List users = userDAO.getUserByPage(page); {B[i|(xQx
returnnew Result(page, users); Vv zd>yII
} /a]+xL
3 \kT#nr
} I{M2nQi
{8t;nsdm!
&jj\-;=~Ho
f(9w FT
&*0!${B
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 [TNYPA>{
[t ^|l?
询,接下来编写UserDAO的代码: `5>IvrzXrK
3. UserDAO 和 UserDAOImpl: Bw{W-&$o
java代码: &qo'ge8p
EkJo.'0@
V,2O`D%
/*Created on 2005-7-15*/ }}ogdq
package com.adt.dao; :pNZQX
>+8mq]8^
import java.util.List; Q>X ;7nt0
5Lue.U%a
import org.flyware.util.page.Page; !4
6^}3
b#$:XS
import net.sf.hibernate.HibernateException; 4$_8#wB1&
'o5[:=K
/** LxMOs Nv
* @author Joa gs9f2t
*/ GF
k?Qf{u
publicinterface UserDAO extends BaseDAO { gAR];(*
>.B+xn=
publicList getUserByName(String name)throws 6.ap^9AD
n+xM))
HibernateException; mv+.5X
ph69u #Og
publicint getUserCount()throws HibernateException; 71wyZJ
o2%"Luf<
publicList getUserByPage(Page page)throws uV;Z
sX@e1*YE_
HibernateException; dLjT^ 9
_I@dt6oF
} F.AO
B [y1RI|9
sz}Nal$AC
4u:{PN
SqEO
]~
java代码: c-gaK\u}j}
^B5Hjf9
QAX+oy
/*Created on 2005-7-15*/ 1)k))w 9
package com.adt.dao.impl; G|H\(3hHLZ
Y/{Z`}
import java.util.List; 6#dx%TC
.}j@(D
import org.flyware.util.page.Page; \QHM7C T
jQf1h|e
import net.sf.hibernate.HibernateException; \*_qP*vq@
import net.sf.hibernate.Query; sba0Q[IY
VeCpz[r
import com.adt.dao.UserDAO; heRQ|n.Dz)
&(wik#S
/** Av/|={i
* @author Joa .k[Ptx>
*/ ^QXUiXzl
public class UserDAOImpl extends BaseDAOHibernateImpl |Z!C`G[
?5Lom#^
implements UserDAO { vR:t4EJ`
q!NwfXJM
/* (non-Javadoc) qf
]ax!bK
* @see com.adt.dao.UserDAO#getUserByName t-/%|@?D
RCoz;|c`P
(java.lang.String) F[~qgS*;
*/ #U!J2240
publicList getUserByName(String name)throws ~lQ]PKJ"
]\Ez{MdAT
HibernateException { mz/KGZ5t
String querySentence = "FROM user in class R[o KhU
' Bdvqq
com.adt.po.User WHERE user.name=:name"; zYH6+!VBH#
Query query = getSession().createQuery UIzk-.<
_{T`ka
(querySentence); w6Ue5Ix,!
query.setParameter("name", name); e?F r/n
return query.list(); X/'B*y'=U
} ?jb7Oq#[
$YL}rM
/* (non-Javadoc) >Utn[']~
* @see com.adt.dao.UserDAO#getUserCount() ? p\'S
w:
*/ GAPZt4Z2
publicint getUserCount()throws HibernateException { mo<g'|0
int count = 0; hZ$* sf
String querySentence = "SELECT count(*) FROM l*pCG`@J#
US4X CJxB
user in class com.adt.po.User"; vChkSY([
Query query = getSession().createQuery #16)7
vE{QN<6T
(querySentence);
%lEPFp
count = ((Integer)query.iterate().next YIjBKh
c9DX
()).intValue(); 6V!yfps)
return count; E&]S No<
} :90DS_4
$g5pKk
/* (non-Javadoc) Rm6<"SLV
* @see com.adt.dao.UserDAO#getUserByPage "PnYa)?1
-3haLdRk6
(org.flyware.util.page.Page) 0]NjsOU=
*/ A9F&XF7{
publicList getUserByPage(Page page)throws &>sG xK
Jtc?p{
HibernateException { h]G}E9\l
String querySentence = "FROM user in class vFy/
R"K{@8b
com.adt.po.User"; W~R_-
]k@g
Query query = getSession().createQuery 2<YHo{0BLS
lD\lFN(:
(querySentence); #& Rx(
query.setFirstResult(page.getBeginIndex()) rHN>fySn7
.setMaxResults(page.getEveryPage()); %`%1W
MO
return query.list(); 7dN]OUdi
} 'X{7b
<
F;`es%8
} )p ,-TtV
hoeOdWIpf
i^="*t\i
, lT8gQ|u
;LthdY()n(
至此,一个完整的分页程序完成。前台的只需要调用 &`t-[5O\
"'s`?
userManager.listUser(page)即可得到一个Page对象和结果集对象 Mm|HA@W^
rcNM,!dZ
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$M^<z
'$l*FWOEal
webwork,甚至可以直接在配置文件中指定。 (w@|:0t^y[
@v@'8E Q
下面给出一个webwork调用示例: '}LH,H:%G
java代码: (w4#?_
m[]pIXc(
E70
/*Created on 2005-6-17*/
NAHQ:$
package com.adt.action.user; Xs*~[k'
Mx0c
#d.
import java.util.List; 7ug mZO}lL
@^#y23R U
import org.apache.commons.logging.Log; u.$.RkNMQ
import org.apache.commons.logging.LogFactory; B% BO
import org.flyware.util.page.Page; kRZ(
! X*L<)=nh
import com.adt.bo.Result; rDm>Rm=
import com.adt.service.UserService; cb|`)"<HN
import com.opensymphony.xwork.Action; &UQKZ.
Pbd#Fu;
/** $Iv*?S"2
* @author Joa j@2-^q:`
*/ ukvz#hdE
publicclass ListUser implementsAction{ j^986
g)xzy^2e
privatestaticfinal Log logger = LogFactory.getLog Y==# yNwM
SAly~(r?/
(ListUser.class); |M0 XLCNd_
goWD~'\
private UserService userService;
g`3g#h$
p;X[_h
private Page page; <N+l"Re#]
~"+[VE5
privateList users; RSzp-sKB
E8#y9q
/* j3sUZg|d
* (non-Javadoc) q>!T*BQ
* m <aMb
* @see com.opensymphony.xwork.Action#execute() &A=d7ASN=
*/ 9`-ofwr'|
publicString execute()throwsException{ ]^ZC^z;H
Result result = userService.listUser(page); 2|w(d
page = result.getPage(); D[:7B:i
users = result.getContent(); &!KJrQ
return SUCCESS; V>4 !fD=
} H*; J9{
*!'00fv
/** SS(jjpe&,
* @return Returns the page. 75I*&Wl
*/ Kxh)'aal
public Page getPage(){ ,Sghi&Ky
return page; F''4 j8
} z8vFQO\I"
P^VV8Z>\&
/** (J$JIPF
* @return Returns the users. $P4hNb
*/ YPGn8A
publicList getUsers(){ B RD>q4w
return users; r$G;^
} Eu1s
-}PD0Pzg;=
/** [ivJ&'vB
* @param page JFR,QUT
* The page to set. TS-m^Y'R
*/ |~#!e}L(
publicvoid setPage(Page page){ }5zH3MPQH
this.page = page; cf@:rHB}
} h#;fBQ]
\A keC 6[D
/**
E2!;W8M
* @param users }^)M)8zS
* The users to set. !\+SE"ml
*/ gHYYxhW$
publicvoid setUsers(List users){ B6OggJ9Iq
this.users = users; v\$XhOK
} tdZ: w
H)t8d_^|j
/** vA(3H/)-
* @param userService 9~Q.[ A
* The userService to set. k3^S^Bv\
*/ 7QQ1oPV
publicvoid setUserService(UserService userService){ ~`8`kk8
this.userService = userService; f<0-'fGJd
} CZ|Y o
} &eK8v]|"W
jO!!. w
y4P mL
?Za1
b
L{<E'#@F
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, is#?O5:2
Kax85)9u
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 %8hhk]m\b>
wU?2aXY
么只需要: RHVMlMX
java代码: W#-M|
F-UY~i8
jDy
<?xml version="1.0"?> .VTHZvyn
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork a8A8?:
!oM1
1.0//EN" "http://www.opensymphony.com/xwork/xwork- }3M\&}=8
&d9";V"E
1.0.dtd"> F0Rk[GM
WElB,a-RCp
<xwork> vIz~B2%x
J}%&;uv
<package name="user" extends="webwork- wQ4/eQ*
M6y:ze
interceptors"> "d%":F(
9b()ck-\F#
<!-- The default interceptor stack name 9dSKlB5J
+}X@{DB
--> 80axsU^H0
<default-interceptor-ref M0"xDvQ
pbloL3d.;+
name="myDefaultWebStack"/> 0'VwObq
fu\M2"e
<action name="listUser" /1o~x~g(b
L[##w?Xf.
class="com.adt.action.user.ListUser"> M^k~w{
<param +r4^oT[-
GZ*cV3Y`&
name="page.everyPage">10</param> ,%>/8*
<result UT]LF#.(
#Z (B4YO
name="success">/user/user_list.jsp</result> /,GDG=ra
</action> ze!7qeW
;]vE"M x$
</package> 5BTQJa
4K)P Yk
</xwork> CXvL`d"
~hYG%
0j_`7<,:
M(I 2M
g2w0#-
b@z/6y!
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 hPD2/M
dhsQfWg#}
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。 }3=]1jH6
),dXaP[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 R279=sO,J
d,+d8X
>g8Tl`P,iN
*%\z#Bje@
|BF4F5wC?
我写的一个用于分页的类,用了泛型了,hoho m~#98ZJ^
NR^z!+oSR
java代码: T+N%KRl
Z?CmD;W
w*\)]bTs
package com.intokr.util; ?IGT !'
y`7BR?l
import java.util.List; 4~DFtWbf
hSo\
/** JEs?Rm1^.
* 用于分页的类<br> b":cj:mxL
* 可以用于传递查询的结果也可以用于传送查询的参数<br> YM/GSSq
* Rb|\!
* @version 0.01 1+.(N:) +
* @author cheng "qR
qEpD%
*/ "4oY F:h
public class Paginator<E> { Ej8EQ%P
privateint count = 0; // 总记录数 >&Y8VLcK
privateint p = 1; // 页编号 (lTM^3
}
privateint num = 20; // 每页的记录数 7`|$uIM`
privateList<E> results = null; // 结果 $Rd74;edn
*|a_(bQ4@
/** -:AknQq
* 结果总数 *<"xF'C
*/ ^)D[ W(*
publicint getCount(){ _l{GHz
return count; .E"hsGH9h
} NuLQkf)
gGH<%nHW1
publicvoid setCount(int count){ 7b \Hbg Z
this.count = count; aXhgzI5]
} ]B5q v6
rpQB#
Pz
/** ,eF}`
* 本结果所在的页码,从1开始 PIsMx -i0
* bL ] *K$
* @return Returns the pageNo. qOqQt=ObU
*/ E+]gC
publicint getP(){ `N]!-=o
return p; u-f_,],p
} al(t-3`<
E[)`+:G]
/** Z Z\,iT
* if(p<=0) p=1 I+kDx=T!
* %q`_vtUT
* @param p {: T'2+OH>
*/ gH(,>}{^K
publicvoid setP(int p){ K8ecSs}}J
if(p <= 0) b'3w.%^
p = 1; 'Oyz/P(p
this.p = p; E#Smi507p
} 0x4p!5
$*\[I{Zau}
/** jyb/aov
* 每页记录数量 )F8G q,
*/ r**u=q%p
publicint getNum(){ 4S`2")V
return num; Fi14_{
} [x
kbzJ
#9F=+[L
/** j[.R|I|
* if(num<1) num=1 >MauuL,.j
*/ 4'cdV0]
publicvoid setNum(int num){ n?
e&I>1W
if(num < 1) C1:efa<wV
num = 1; U^-:qT;CX
this.num = num; 3<88j&9
} KnaQhZ
}*4 XwUM e
/** D'$ki[{,
* 获得总页数 vSb$gl5H
*/ !iN=py
publicint getPageNum(){ S zR7:U
return(count - 1) / num + 1; R^.E";/h
} k|(uIU* ]
F*_g3K!!
/** xc7Wk&{=
* 获得本页的开始编号,为 (p-1)*num+1 wR@&C\}9
*/ U p=J&^.
publicint getStart(){ bS=aFl#
return(p - 1) * num + 1;
] lE6:^V
} 0>}
FNRC
h:\WW;s[B
/** dO
=fbmK
* @return Returns the results. u [5*RTE
*/ TcPYDAa
publicList<E> getResults(){ 5V;BimI
return results; b_ +dNoB
} 9*pH[vH
3J%(2}{y
public void setResults(List<E> results){ 4E/Q+^?
this.results = results; xE`uFHuS}
} u(iEuF;7
+F=j1*'&
public String toString(){ `CP#S7W^
StringBuilder buff = new StringBuilder 9%55R >s$
FR"yGx#$
(); FH:^<^M
buff.append("{"); 1$2'N~`#U
buff.append("count:").append(count); dtD)VNkBZ
buff.append(",p:").append(p); e"Kg/*Ji1
buff.append(",nump:").append(num); `a2%U/U
buff.append(",results:").append SIQ 7oxS4
q$6fb)2I]e
(results); "Qj;pqR
buff.append("}"); r%QTUuRXC3
return buff.toString(); In<L?U?([D
} sH(@X<{p
kcGs2Y_*&
} )!M %clm.
\ <b-I
}i0(^"SoXZ