Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 bw<w
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Iv(Qa6(
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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 ZB[(Tv1
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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 6!B^xm.R @
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分页支持类: m*!f%}T
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java代码: k=7Gr;;l=p
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package com.javaeye.common.util; p08kZ
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import java.util.List; y-#
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publicclass PaginationSupport { =#(0)p$EC
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publicfinalstaticint PAGESIZE = 30; ole|J
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privateint pageSize = PAGESIZE;
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privateList items; -~][0PVL9
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privateint totalCount; j`R<90~/
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privateint[] indexes = newint[0]; i<m$#6<Z
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privateint startIndex = 0; |qlS6Aln
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public PaginationSupport(List items, int w,Z"W;|
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totalCount){ i_u
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setPageSize(PAGESIZE); w(/DTQc~d
setTotalCount(totalCount); -@2'I++"@
setItems(items); A)Qh
setStartIndex(0); Kej|1g1f
} Y}LLOj@L
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public PaginationSupport(List items, int ,;.B4
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totalCount, int startIndex){ {pDTy7!Hs
setPageSize(PAGESIZE); UP;Q= t
setTotalCount(totalCount); ivzAlwP
setItems(items); v**z$5x9
setStartIndex(startIndex); kG1;]1tT#
} [q-;/ed
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public PaginationSupport(List items, int *bA+]&dj\
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totalCount, int pageSize, int startIndex){ 9g
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setPageSize(pageSize); ?MC(}dF0
setTotalCount(totalCount); Xsd$*F@<
setItems(items); \+k, :8s/
setStartIndex(startIndex); ^/>Wr'w
} 4\N_ G
@
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publicList getItems(){ #JA}LA"l
return items; 5"JU?e59M
} F7{R~mS;
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publicvoid setItems(List items){ p jKt:R}
this.items = items; mG)8U{L
} M$Fth*q{GD
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publicint getPageSize(){ $!G` D=
return pageSize; ]@X{dc
} 47IY|Jdz
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publicvoid setPageSize(int pageSize){ m0A# 6=<
this.pageSize = pageSize; i&`!|X-=R
} 2sKG(^=Z
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publicint getTotalCount(){ :l+_ja&o
return totalCount; z% V* K
} DVI7]+=nV
}[ ].\G\G
publicvoid setTotalCount(int totalCount){ !?nu?
if(totalCount > 0){ ]cIu|bRO
this.totalCount = totalCount; }Y Q:6I
int count = totalCount / P,i"&9 8
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pageSize; JO2xT#V
if(totalCount % pageSize > 0) %>Bko,ET
count++; p8=|5.
indexes = newint[count]; u4YM^* S.
for(int i = 0; i < count; i++){ p*|ah%F6N
indexes = pageSize * 6xHi\L
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i; GR%{T'ZD`
} Q',m{;;
}else{ QY@u}&m%o
this.totalCount = 0; B7HQR{t
} nq'M?c#E
} xO7Yt
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publicint[] getIndexes(){ b3\B8:XFo|
return indexes; HT"gT2U+
} x=-0 zV
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publicvoid setIndexes(int[] indexes){ )lh8
k{
this.indexes = indexes; vZ@g@zB4o0
} G>%AZr{M
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publicint getStartIndex(){ ]#zZWg
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return startIndex; Vl<9=f7[
} Jx$iwu
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publicvoid setStartIndex(int startIndex){ _ h9o@
if(totalCount <= 0) h*Je35
this.startIndex = 0; \iru7'S
elseif(startIndex >= totalCount)
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this.startIndex = indexes zAs&%OjG
IU#x[P!
[indexes.length - 1]; Qz+sT6js-
elseif(startIndex < 0) #Qh>z%Mn^3
this.startIndex = 0; g9KTn4
else{ |]W2EV ,b
this.startIndex = indexes GK?4@<fY
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[startIndex / pageSize]; 8>N wCjN
} c?K~/bx.
} *C6 D3y
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publicint getNextIndex(){ uS<_4A;sD,
int nextIndex = getStartIndex() + XE rUS80
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pageSize; U
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if(nextIndex >= totalCount)
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return getStartIndex(); *(QH{!-$s
else <7)Fh*W@
return nextIndex; kl}Xmw{tJ
} WeMAe
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publicint getPreviousIndex(){ A\$
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int previousIndex = getStartIndex() - Dl C@fZD
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pageSize; s8<gK.atl
if(previousIndex < 0) W5pb;74|
return0; osHCg
else
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return previousIndex; 3l4NC03I&
} j9R6ta3\l
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} +?m0Q;%b
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抽象业务类 "Fnq>iR-
java代码: 'Ot,H_pE
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/** r"{<%e
* Created on 2005-7-12 QM<y`cZ8
*/ #8h;Bj
package com.javaeye.common.business; V416g |lBO
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import java.io.Serializable; kkCZNQ~I
import java.util.List; (Ddp|a"b
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import org.hibernate.Criteria; O4iC]5@
import org.hibernate.HibernateException; Q<(YP.k
import org.hibernate.Session; JXqr3Np1
import org.hibernate.criterion.DetachedCriteria; g);^NAA
import org.hibernate.criterion.Projections; \2C`<h$fN
import /t%u"dP"T~
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org.springframework.orm.hibernate3.HibernateCallback; 9~\kF5Q"
import ,e722wz
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org.springframework.orm.hibernate3.support.HibernateDaoS ]0V}D,V($
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upport; ,m3e?j@;r
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import com.javaeye.common.util.PaginationSupport; <Zb/
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public abstract class AbstractManager extends wK_]/Q-L
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HibernateDaoSupport { 2x]>l?
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privateboolean cacheQueries = false; !^oV #
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privateString queryCacheRegion; SLL3v,P(7
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publicvoid setCacheQueries(boolean &)d$t'7p
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cacheQueries){ _gj&$zP
this.cacheQueries = cacheQueries; z;tI D~Y
} K)tQ]P
}Db[ 4
publicvoid setQueryCacheRegion(String zE T^T5>:
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queryCacheRegion){ ?t&kb7
this.queryCacheRegion = ;ea]$9
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queryCacheRegion; a]17qMl
} z
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publicvoid save(finalObject entity){ ^ 2GHe<Y
getHibernateTemplate().save(entity); C&LBr|
} ~)LH='|h\}
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publicvoid persist(finalObject entity){ 9_s6l
getHibernateTemplate().save(entity); (
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} G'2#9<c*
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publicvoid update(finalObject entity){ l:0s2
getHibernateTemplate().update(entity); k(>h^
} ,[S+T.Cu
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publicvoid delete(finalObject entity){ 5Wyz=+?m|
getHibernateTemplate().delete(entity); ^'CPM6J
} WG*t::NN
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publicObject load(finalClass entity, fH`P[^N
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finalSerializable id){ ~\ ,w {
return getHibernateTemplate().load ](tx<3h
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(entity, id); bmN q[}
} |b-9b&
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publicObject get(finalClass entity, U~h'*nV&
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finalSerializable id){ S)QAXjH
return getHibernateTemplate().get 5w %_$x
.)}@J5P)
(entity, id); Fc~'TBf,,`
} rG#Z=*b%
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publicList findAll(finalClass entity){ f|^dD`
return getHibernateTemplate().find("from gu #-O?B
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" + entity.getName()); >fH=DOz$&
} ?9l [y
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publicList findByNamedQuery(finalString S3L~~X/=
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namedQuery){ KIR'$ 6pn~
return getHibernateTemplate u6`=x$&
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().findByNamedQuery(namedQuery); 'n<iU st
} 8ElKD{.BU8
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publicList findByNamedQuery(finalString query, [((;+B
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finalObject parameter){ )tCX
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return getHibernateTemplate ;<UW A.
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().findByNamedQuery(query, parameter); sAg Kg=)
} Vi4~`;|&b+
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publicList findByNamedQuery(finalString query, piU/&
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finalObject[] parameters){ ##Z_QB(;
return getHibernateTemplate 0IQ'3_
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().findByNamedQuery(query, parameters); F:6SPY
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} j5
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publicList find(finalString query){ DJP2IP
return getHibernateTemplate().find [`]4P&
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(query); ICAH G7 ,
} Cgz D$`~
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publicList find(finalString query, finalObject CRbdAqofV
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parameter){ gKOOHUCb
return getHibernateTemplate().find /m!Cc/Hv
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(query, parameter); hDV20&hq
} z&V+#Ws/
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public PaginationSupport findPageByCriteria &qS[%K )
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(final DetachedCriteria detachedCriteria){ \^#~@9
return findPageByCriteria a,78l@d(
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,t)x{I;C)
} !?^b[
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public PaginationSupport findPageByCriteria au,t%8AC
CR2_;x:0
(final DetachedCriteria detachedCriteria, finalint @y31NH(
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startIndex){ 7<H
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return findPageByCriteria &sF^Fgg{
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(detachedCriteria, PaginationSupport.PAGESIZE, nk3y"ne7
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startIndex); `Y?87f:SP
} Qv-@Zt!8
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public PaginationSupport findPageByCriteria ." $
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(final DetachedCriteria detachedCriteria, finalint d6i6hcQE
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pageSize, ~SSU`
finalint startIndex){ 1He{v#
return(PaginationSupport) /t-fjB{=G
;\MW$/[JCy
getHibernateTemplate().execute(new HibernateCallback(){ S(:l+JP
publicObject doInHibernate 2S' {!A
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(Session session)throws HibernateException { <'G~8tA%v
Criteria criteria = oq*N_mP0
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detachedCriteria.getExecutableCriteria(session); kF>o.uSV
int totalCount = 5{$LsL
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((Integer) criteria.setProjection(Projections.rowCount aTBR|US
f3|@|'
;
()).uniqueResult()).intValue(); 1wW)tNKIF
criteria.setProjection :R.&`4=X
$)H@|<K
(null); Q?AmOo-a
List items = Y
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criteria.setFirstResult(startIndex).setMaxResults ;+1RUv
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(pageSize).list(); KgN)JD>
PaginationSupport ps = 0j(M*
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new PaginationSupport(items, totalCount, pageSize, _ pO `
7 h y&-<
startIndex); .d/:30Y
return ps; b|zg<
} )etmE
}, true); JY!l!xH(6
} wv^rS^~
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public List findAllByCriteria(final G|8%qd
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DetachedCriteria detachedCriteria){ -CH`>
return(List) getHibernateTemplate ~ d^<_R
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().execute(new HibernateCallback(){ Q!,<@b)
publicObject doInHibernate c"!lwm3b
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(Session session)throws HibernateException { G;3~2^lB\
Criteria criteria = 3?E8\^N\n
. |*f!w}5
detachedCriteria.getExecutableCriteria(session); .}')f;jH5<
return criteria.list(); V0nn4dVO
} 80M;4nH^5
}, true); 4lKVY<
} CXtU"X
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public int getCountByCriteria(final drwgjLC+
G,= yc@uq
DetachedCriteria detachedCriteria){ TO,rxf
Integer count = (Integer) 9{j66
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getHibernateTemplate().execute(new HibernateCallback(){ \8OO)98'
publicObject doInHibernate PN+G:Qv
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(Session session)throws HibernateException { c^8o~K>w84
Criteria criteria = Fyyg`J
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detachedCriteria.getExecutableCriteria(session); 6B$q,"%S@
return vFrt|JC_{
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criteria.setProjection(Projections.rowCount 4(?G6y)
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()).uniqueResult(); `nR %Cav,U
} +5v}q.:+
}, true); !e#xx]v3
return count.intValue(); y'ja< 1I>
} !0/z>#b
} KRsAv^']
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用户在web层构造查询条件detachedCriteria,和可选的 7dh1W@\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 :&'{mJW*{t
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PaginationSupport的实例ps。 _baYn`tFw-
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ps.getItems()得到已分页好的结果集 ZeasYSo4P
ps.getIndexes()得到分页索引的数组 BH0!6Oq
ps.getTotalCount()得到总结果数 Oi:JiD=
ps.getStartIndex()当前分页索引 c)C 5KaiPG
ps.getNextIndex()下一页索引 z)F#u:t
ps.getPreviousIndex()上一页索引 D_|B2gdZY
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (0*v*kYdL+
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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 +h[e0J|v{
5S/>l_od$2
一下代码重构了。 "!&B4
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我把原本我的做法也提供出来供大家讨论吧: #0MK(Ut/
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首先,为了实现分页查询,我封装了一个Page类: Rlg#z4m
java代码: QJ4AL3
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/*Created on 2005-4-14*/ *8!w&ME+.
package org.flyware.util.page; IlHY%8F{
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/** k8&FDz
* @author Joa RebTg1vGu
* 7~.ZE
*/ J~J@ ]5/
publicclass Page { vj3isI4lU
R`He^
/** imply if the page has previous page */ ?vu|o'$T,
privateboolean hasPrePage; qyv"Wb6+
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/** imply if the page has next page */ Xu]h$%W
privateboolean hasNextPage; ="lI i$>O
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/** the number of every page */ 94z8B;+H]
privateint everyPage; AP@<r
"]<}Hy
/** the total page number */ F"BL#g66
privateint totalPage; 4Iq5+Q
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/** the number of current page */ 0ny{)Sd6um
privateint currentPage; [aNhP;<
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/** the begin index of the records by the current 7:kCb[ji"
.Cfp'u%\;
query */ hNVMz`r
privateint beginIndex; PSEWL6=]N
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/** The default constructor */ _FFv#R*4
public Page(){ =AzOnXW:S
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} tj#b_u z
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/** construct the page by everyPage dgY5ccP
* @param everyPage I9,8HtnA
* */ PHl4 vh#E!
public Page(int everyPage){ H` Lu"EK
this.everyPage = everyPage; Cn/q=
} 4L$};L
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/** The whole constructor */ pLJeajv)z
public Page(boolean hasPrePage, boolean hasNextPage, 43F^J%G
7H?!RYrx
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int everyPage, int totalPage, >E~~7Yal
int currentPage, int beginIndex){ ;Lqm#]C
this.hasPrePage = hasPrePage; |} 9GHjG
this.hasNextPage = hasNextPage; O E]~@eU
this.everyPage = everyPage; +ruj
this.totalPage = totalPage; r.Lx%LZ\^
this.currentPage = currentPage; $4:~*IQ
this.beginIndex = beginIndex; gvK"*aIj
} X)y*#U
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/** P1e5uJkd
* @return Mi;Tn;3er
* Returns the beginIndex. y
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*/ W >Kp\tD
publicint getBeginIndex(){ |:}L<9Sq
return beginIndex; BHIM'24bp
} ELD
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/** g] 7{5
* @param beginIndex 7UeE(=Hr5
* The beginIndex to set. __oY:d(~
*/ (:</R$I
publicvoid setBeginIndex(int beginIndex){ FF~on06!
this.beginIndex = beginIndex; $9LGdKZ_D
} .b!OZ
_RA{SO
/** W>aQ
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* @return HM(bR"E
* Returns the currentPage. nm{'HH-4
*/ L@d]R MNv
publicint getCurrentPage(){ E.zYi7YUKK
return currentPage; bv:0EdVr
} bn<I#ZH2
t(uB66(_F
/** \S|VkPv
* @param currentPage &Cx yP_
* The currentPage to set. 14@q $}sf
*/ .>AFf9P
publicvoid setCurrentPage(int currentPage){ 82^
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this.currentPage = currentPage; )n[`Z#
} 7>W+Uq
rS,*s'G
/** )Bm^aMVl3
* @return @vQ;>4 i.
* Returns the everyPage. P@! Q1pr
*/ ~]6Oz;~<3
publicint getEveryPage(){ ^G7n#
return everyPage; #V(Hk )
} {3F}Slb
g# 9*bF
/** ya*q; D
* @param everyPage #Kb)>gzT
* The everyPage to set. Bcd0
*/ |aOnV,}
publicvoid setEveryPage(int everyPage){ {8>_,z^P)
this.everyPage = everyPage; |+$j(YuH
} $+)x)1
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/** Tg{dIh.Q~O
* @return U(Hq4D
* Returns the hasNextPage. -V<=`e
*/ nHhD<a!
publicboolean getHasNextPage(){ (-G(^Tn
return hasNextPage; ek0;8Ds9
} e)
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/** D .oS8'
* @param hasNextPage [jtj~]&mO
* The hasNextPage to set. At^DY!3vx
*/ |Z^c#R
publicvoid setHasNextPage(boolean hasNextPage){ f'zFg["aZS
this.hasNextPage = hasNextPage; u_/OTy
} T$8$9D_u
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/** TF}4X;3Dsy
* @return KSpC%_LC
* Returns the hasPrePage. ekk&TTp#
*/ WY.\<$7
publicboolean getHasPrePage(){ dO4U9{+
return hasPrePage; S;AnpiBM8
} X-2S*L'
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/** (=&bo p
* @param hasPrePage +/_B/[e<>
* The hasPrePage to set. ;(iUY/ h[h
*/ 2O)Kn
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publicvoid setHasPrePage(boolean hasPrePage){ Uub%s`O
this.hasPrePage = hasPrePage; f6_|dvY3
} BQfAen]
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/** O t4+VbB6
* @return Returns the totalPage. qu~"C,
* T[$hYe8%^
*/ DSG +TA"
publicint getTotalPage(){ Ai_|)
return totalPage; +q,n}@y=
} [Jh))DIx
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/** uc (yos
* @param totalPage ]B.,7
* The totalPage to set. U@t?jTMBkO
*/ `q{'_\gVt(
publicvoid setTotalPage(int totalPage){ ^)P5(fJ
this.totalPage = totalPage; QO`Sn N}
} YHv,Z|.w
s1b\I6&:J
} r
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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 8 P y_Y>
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个PageUtil,负责对Page对象进行构造: Ty`=U>K|
java代码: Q_h+r!b
XK9*,WA9r
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/*Created on 2005-4-14*/ +q?0A^C>
package org.flyware.util.page; %1d6j<7
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import org.apache.commons.logging.Log; M]zNW{Xt
import org.apache.commons.logging.LogFactory; ;? QAPTz
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/** k.f:nv5JO
* @author Joa Ox1QP2t6Y
* ?BZ`mrH^
*/ FJH8O7
publicclass PageUtil { b6M)qt9R
y/*Tvb #TJ
privatestaticfinal Log logger = LogFactory.getLog y(BLin!O.
:v ~q
(PageUtil.class); i]WlMC6
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/** -.3k
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* Use the origin page to create a new page 1ORi]`
* @param page ,colGth54
* @param totalRecords MM$"6Jor
* @return ~a,'
*/ tce8*:rNH
publicstatic Page createPage(Page page, int tdK^X1
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totalRecords){ 9rc
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return createPage(page.getEveryPage(), dp W%LXM_
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page.getCurrentPage(), totalRecords); SytDo (_=W
} |W];v@b\y
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/** ee[NZz
* the basic page utils not including exception \`# 0,pLr
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handler k}qiIMdI
* @param everyPage =xP{f<`
* @param currentPage Qj[O$L0 $
* @param totalRecords =x]dP.
* @return page &h[}5
*/ HKw4}FC*
publicstatic Page createPage(int everyPage, int \,t<{p_Q
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currentPage, int totalRecords){ ^C
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everyPage = getEveryPage(everyPage); GQWTQIl]
currentPage = getCurrentPage(currentPage); IV*$U7~
int beginIndex = getBeginIndex(everyPage, )C6 7qY[P
3o^M%
currentPage); cNvcpv
int totalPage = getTotalPage(everyPage, )S?}huX
EOC"a}Cq-
totalRecords); LRs;>O
boolean hasNextPage = hasNextPage(currentPage, o)WSMV(&f
5(Oc"0''H
totalPage); y$NG ..S
boolean hasPrePage = hasPrePage(currentPage); !7?wd^C'f
~cwwB{
returnnew Page(hasPrePage, hasNextPage, W{aN S@1
everyPage, totalPage, 4/_|Qy
currentPage,
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5)6%D
beginIndex); Bk<P~-I
} v:;cTX=x`#
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z
privatestaticint getEveryPage(int everyPage){ rfpxE>_|G
return everyPage == 0 ? 10 : everyPage; < Ifnf6~
} d5hE!=
G> >_G<x
privatestaticint getCurrentPage(int currentPage){ g7i6Yj1
return currentPage == 0 ? 1 : currentPage; \$"Xr
} IrC=9%pd$R
Eq{TZV
privatestaticint getBeginIndex(int everyPage, int "-%H</
Q8i6kf!
currentPage){ U)8]pUI+/P
return(currentPage - 1) * everyPage; :_ox8xS4
} +6atbbe}
*E'K{?-K
privatestaticint getTotalPage(int everyPage, int ?f&I"\y
F)Lbr>H?I
totalRecords){ RUKSGj_NJ
int totalPage = 0; P+h&tXZn8
ZbUf|#GTB
if(totalRecords % everyPage == 0) w3D_ c~
totalPage = totalRecords / everyPage; Ip0q&i<6
else -f=hL7NW
totalPage = totalRecords / everyPage + 1 ; 2Fi*)\{
eHR<(8c'f
return totalPage; .EO1{2=
} >^&+,*tsS4
-yeT $P&|
privatestaticboolean hasPrePage(int currentPage){ \Z':hw
return currentPage == 1 ? false : true; Sqs`E[G*
} Z]<_a)>
/&yT2p
privatestaticboolean hasNextPage(int currentPage, C#>C59
^> fs
int totalPage){ O;2 u1p'iP
return currentPage == totalPage || totalPage == }^muAr
%L3]l
0 ? false : true; )Yml'?V"
} 'Nh^SbD+_|
D3PF(Wx
Bh?;\D'YC
} $$a"A(Y
}kpkHq"`f
a0R]hENC
7
<xxOY>y
\!r^6'A
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Y{KJk'xN5W
cO:x{~
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \IKr+wlN8
#^Y,,GA
做法如下: Ty=}A MMyE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v,;?+Ck
#_d%hr~d
的信息,和一个结果集List: s>5 Z
java代码: +-hmITJv
{F j`'0Xu;
rfjQx]3pB
/*Created on 2005-6-13*/ _bX)fnUu
package com.adt.bo; 7u zN/LAF
{-xnBx
import java.util.List; DxlX-
{#vo^& B
import org.flyware.util.page.Page; b7-a0zaN
b{&@Lm0Tn
/** hXCDlCO
* @author Joa '&9b*u";x(
*/ /SiQw7yp%
publicclass Result { L-XTIL$$
Nx99dr
private Page page; %^S1 fUwT
/=N`P &R#
private List content; J8jbtL O'
O%Mh
g\#B
/** WI%,m~
* The default constructor d^7<l_u~ !
*/ 0^+W"O
public Result(){ mU!c;O
super(); 99`xY$
} R$q:Ct
MStaP;|
/** kW"N~Xw)
* The constructor using fields ?g 3sv5\u
* /O9z-!Jz
* @param page Q]8r72uSk
* @param content di|l?l^l
*/ K$4Ky&89
public Result(Page page, List content){ 2n\EZ
this.page = page; 7*sB"_U2
this.content = content; 8qT/1b
} Y9ru~&/o$
}u
:sh >2
/** q N>j2~
* @return Returns the content. QgP
UP[
*/ .k}h'nE
publicList getContent(){ #soWX_>
return content; &a V`u?'e
} zJPzI{-w|
;e+ErN`a.~
/** ]\{EUx9
* @return Returns the page. ~MOIrF
*/ 0ZO!_3m$r
public Page getPage(){ I'JFt>]
return page; YtFtU;{
} >y5~:L
Up~#]X
/** .RdnJ&K*
* @param content kEi!q
* The content to set. d+8Sypv^4*
*/ [5H#ay
public void setContent(List content){ BPW2WSm@<
this.content = content; 5~v({R.
} yTv#T(of
v81<K*w`P
/** ?e0ljx;
* @param page />H9T[3=
* The page to set. @PutUYz
*/ G22u+ua
publicvoid setPage(Page page){ (m13
ong
this.page = page; i!(u4wTFF
} `$05+UU
} o!:
u{J$]%C
;tlvf?0!
m;'ebkq
_vm ~yKId
2. 编写业务逻辑接口,并实现它(UserManager, =nGgk}Z
:wtK'ld
UserManagerImpl) vr"O9L
w
java代码: +xp)la.
*|Tx4Qt
OQ&l/|{O0?
/*Created on 2005-7-15*/ 1N,</<"
package com.adt.service; ]V^ >aUlj
`p#tx.o
import net.sf.hibernate.HibernateException; ,N93 H3(
u^, eHO
import org.flyware.util.page.Page; T,r?% G{XE
k..AP<hH
import com.adt.bo.Result; evjj~xkte
GCZx-zD~>
/** WUrE1%u
* @author Joa lha)4d
*/ IK1'" S|
publicinterface UserManager { 2{|Z?3FJ^
AT%6K.
public Result listUser(Page page)throws 52ExRG S
xu\s2x$
HibernateException; z.lIlp2:
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} #zRHYZc'T|
j<'ftKk
$7" Y/9Y
xqs ,4bcbY
# ~Doz7~
java代码: ;6:9 EEd
=WT&unw}
_iu~vU)r
/*Created on 2005-7-15*/ (\ge7sE-oo
package com.adt.service.impl; tq}MzKI*
kMJ}sS
import java.util.List; j"K^zh
i-PK59VZ8f
import net.sf.hibernate.HibernateException; EQN)y27poW
eAmI~oku
import org.flyware.util.page.Page; nrHC;R.nE
import org.flyware.util.page.PageUtil; DkX^b:D*f
@R%*; )*F
import com.adt.bo.Result; G9NI`]k
import com.adt.dao.UserDAO; yts@cd`$
import com.adt.exception.ObjectNotFoundException; ?5FlbiT
import com.adt.service.UserManager; %N)B8A9kh
"4\k1H"_
/** "\i H/
* @author Joa /5)*epF+
*/ 9dq"x[
publicclass UserManagerImpl implements UserManager { *?BY+0
!NH(EWER
private UserDAO userDAO; <pfl>Uf
%cLS*=MO
/** ^R=`<jx
* @param userDAO The userDAO to set. H1f='k]SZ
*/ .<zKBv
publicvoid setUserDAO(UserDAO userDAO){ (P`=9+
this.userDAO = userDAO; Pr1qX5> =
} "]#Ij6ml
{;DAKWm@T
/* (non-Javadoc) ||JUP}eP
* @see com.adt.service.UserManager#listUser 4^uSW&`;/
w%.hALN5-C
(org.flyware.util.page.Page) ;+<IWDo
*/ D#UuIZ
public Result listUser(Page page)throws g]lEG>y1R
Bhxs(NO
HibernateException, ObjectNotFoundException { n74\{`8]o
int totalRecords = userDAO.getUserCount(); n9xP8<w8
if(totalRecords == 0) @>HTbs6W
throw new ObjectNotFoundException *mzi ?3
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("userNotExist"); U3X5tED
page = PageUtil.createPage(page, totalRecords); ]:OrGD"
List users = userDAO.getUserByPage(page); _;BwP
returnnew Result(page, users); -T,?'J0 2
} W}f)VC;D
z~#;[bER
} ^K;k4oK
M@R"-$Z
f^FFn32u
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 6N#hN)/
g}NO$?ndg
询,接下来编写UserDAO的代码: m<h%BDSzr{
3. UserDAO 和 UserDAOImpl: fZ$b8
java代码: +4s]#{mP
_K o#36.S
QWk3y"5n<
/*Created on 2005-7-15*/ rP:g`?*V
package com.adt.dao; :~otzI4%!
`gX|q3K\s
import java.util.List; inWLIXC,
)i~AXBt}
import org.flyware.util.page.Page; 17 Ugz?
5dePpF D5
import net.sf.hibernate.HibernateException; @@AL@.*
|NuMDVd+s
/** J#I RbO)
* @author Joa 9MMCWMV
*/ 'XK 'T\m
publicinterface UserDAO extends BaseDAO { #7]Jz.S
zmo2uUEd
publicList getUserByName(String name)throws Dh8ECy5k<*
ye(b 7CX
HibernateException; V4[-:k
Fl)nmwOc
publicint getUserCount()throws HibernateException; uuM1_nD[
-b!?9T?}
publicList getUserByPage(Page page)throws <WUgH6"
#w; "s*
HibernateException; 6 wN*d 5
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P
} ThV>gn5
k+"];
:q/s%`ob
?=7k<a~
{iyJHY
java代码: #x.v)S
+
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8=D,`wog
/*Created on 2005-7-15*/ G ]h
package com.adt.dao.impl; N8nt2r<h
>a975R*g
import java.util.List; Ar)EbGId
y{M7kYWtHV
import org.flyware.util.page.Page; Jj)J5S /
>~ *wPoW
import net.sf.hibernate.HibernateException; mX>N1zAz
import net.sf.hibernate.Query; ]\rQ{No
L]l/w
import com.adt.dao.UserDAO; mx)!] B"
3[Q7'\
/** )"?'~ 5A
* @author Joa %f CkR`:
*/ GJWGT`"
public class UserDAOImpl extends BaseDAOHibernateImpl w7`pbcY,
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implements UserDAO { 8pEA3py
GLIY!BU<C
/* (non-Javadoc) 5BA:^4zr?
* @see com.adt.dao.UserDAO#getUserByName F=Xb_Gd`
RR=WD -l
(java.lang.String) Y-8BL
*/ Rk5#5R n
publicList getUserByName(String name)throws )@9Eq|jMC
E-1u_7
HibernateException { >&\.{ aj
String querySentence = "FROM user in class ;o'>`=Y
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com.adt.po.User WHERE user.name=:name"; "'t f]s
Query query = getSession().createQuery k5>UAea_
R1SFMI
(querySentence); 0e&&k
query.setParameter("name", name); q0q-Coh>
return query.list(); +UWv }|
} aoz+T h3
r<kgYU`
/* (non-Javadoc) q~#>MB}".
* @see com.adt.dao.UserDAO#getUserCount() Wtaz@+
*/ 5mV!mn:H:
publicint getUserCount()throws HibernateException { Pm#/j;
int count = 0;
{Y/0BS2D
String querySentence = "SELECT count(*) FROM %h(%M'm?
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user in class com.adt.po.User"; YFu>`w^Y
Query query = getSession().createQuery .h4NG4FIF
3{.]!
(querySentence); dSKvs"
count = ((Integer)query.iterate().next /pkN=OBR
:LB*l5\
()).intValue(); CT_tJ
return count; n CwA8AG
} v Cej( ))
DZmVm['l
/* (non-Javadoc) G11KAq(
* @see com.adt.dao.UserDAO#getUserByPage gFuK/]gzI
#5h_{q4l
(org.flyware.util.page.Page) Kg~D~
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*/ ez9F!1
publicList getUserByPage(Page page)throws ;F-
mt( Y
prt(xr4@
HibernateException { @f"[*7Q`/
String querySentence = "FROM user in class t$,G%micj
\:F$7 *Ne
com.adt.po.User"; pRh9+1EM;
Query query = getSession().createQuery 4$, W\d
D^>d<LX
(querySentence); } D!tB
query.setFirstResult(page.getBeginIndex()) lvODhoT
.setMaxResults(page.getEveryPage()); 4".I*ij
return query.list(); ._>03, "
} 9W(&g)`
#b&tNZ4!_
} jmgkY)rb R
Fab]'#1q4
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,]ySBAO
R+ \%
至此,一个完整的分页程序完成。前台的只需要调用 )TVd4s(e
xMQ>,nZ
userManager.listUser(page)即可得到一个Page对象和结果集对象 >`&2]Wc)
QjXJo$I6
的综合体,而传入的参数page对象则可以由前台传入,如果用 xx1l Ecj
55ec23m
webwork,甚至可以直接在配置文件中指定。 y@$E5sz
w^zqYGxG)
下面给出一个webwork调用示例: LKI\(%ba#
java代码: o:cTc:l)
3QZm
*.
/"
p),*4@2<
/*Created on 2005-6-17*/ zd8A8]&-
package com.adt.action.user; {R63n
oL R/\Y(
import java.util.List; MYb^G\K
c\>I0HH;!
import org.apache.commons.logging.Log; 6W1+@
q
import org.apache.commons.logging.LogFactory; V&ETt.91Ft
import org.flyware.util.page.Page; X%<qHbKB,
( sl{Rgxe*
import com.adt.bo.Result; XRkUv>Yk
import com.adt.service.UserService; &0[L2x}7
import com.opensymphony.xwork.Action; ;*zLf 9i
1}c/l<d
/** RFS}!_t+|
* @author Joa ;u(*&vRqr^
*/
%X\A|V&
publicclass ListUser implementsAction{ s&o9LdL
Ebj0 {ZL
privatestaticfinal Log logger = LogFactory.getLog rxMo7px@}I
j+-`P5
(ListUser.class); 3t.!5L
05HCr"k
private UserService userService; PX^k;
Z R=[@Oi
private Page page; 9?hF<}1XH}
5CcX'*P
privateList users; (ot56`,k
>*O5Ry:4
/* W\Sc ak>
* (non-Javadoc) a""9%./B
* p`7d9MV^
* @see com.opensymphony.xwork.Action#execute() q[P> s{"
*/ g%]<sRl:-
publicString execute()throwsException{ l}-k>fug
Result result = userService.listUser(page); [cEGkz
page = result.getPage(); ,Js_d
users = result.getContent(); paN=I=:*M
return SUCCESS; S?i^ ~
} p(I^Y{sGI
6ZI7V!k
/** hmLI9TUe6
* @return Returns the page. nXfz@q
*/ 3I}AA.h'00
public Page getPage(){ 't8!.k
return page; yr>J^Et%_
} 4%qmwt*p
yRyRH%p)
/** AriV4 +
* @return Returns the users. V#b*:E.cA
*/ RYC%;h
publicList getUsers(){ /i@.Xg@:
return users; @(x]+*)
} =M@)qy
9%ct
/** q2*)e/}H
* @param page Qz{Vl>"
* The page to set. .uX(-8n ~
*/ !7#*Wdt+P
publicvoid setPage(Page page){ p*cyW l
this.page = page; r?0w5I
} &l{ctP%q
3#udzC
/** {#z47Rz
* @param users Jq>5:"jZ0
* The users to set. y}U'8*,
*/ 60>g{1]
publicvoid setUsers(List users){ 4TU\SP8sM
this.users = users; E:\#Ur2
} Z
*l&<q>#
u5U^}<}y}
/** <R2SV=]Sq#
* @param userService Ug gg!zA
* The userService to set. g;o5m}
*/ w[QC
publicvoid setUserService(UserService userService){ +['1~5
this.userService = userService; /!"sPtIh
} j9Z1=z
} |P9)*~\5
yMgS0
Y3)*MqZlF
DYZk1
vf?m6CMU!
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, brCL"g|}
ct(euPU
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 =7~;*Ts
q8e] {sT'!
么只需要: sFgsEKs
java代码: PP_ar{|7
#iD`Bg!VXc
j{ri]?p
<?xml version="1.0"?> U?:?NC=1{
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork J}@.f-W\j
gd]k3XN$f
1.0//EN" "http://www.opensymphony.com/xwork/xwork- e]:(.Wb- 9
`RE
K,^U
1.0.dtd"> &y3;`A7,
_*t75e$-
<xwork> j3
@Q
=|
r%
lx
<package name="user" extends="webwork- X4bZ4U*
V)oKsO
interceptors">
|gGD3H
VW] ,R1q
<!-- The default interceptor stack name &D7Mv5i0@
r8_MIGM'
--> 9J}^{AA
<default-interceptor-ref 9.Sv"=5gz
sg<c1
name="myDefaultWebStack"/> jq/ CXYv
Gx%f&H~Z^
<action name="listUser" HNX/#?3
kh"APxQ79
class="com.adt.action.user.ListUser"> t0ZaI E
<param GRgpy
=d
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name="page.everyPage">10</param> $j0<ef!
<result o<Rrr,
o~'UWU'#
name="success">/user/user_list.jsp</result> -wnBdL
</action> n*eqM2L
#4& <d.aw'
</package> 1(a+|
l]5!$N*
</xwork> :rN5HOg^9
~=Fp0l)#
+Jq~39
69``j{Z+
t)l^$j!h@
"A}2iI
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 iuoZk5O
9E
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。 v-}D>)M^W
kNUNh[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 9P-I)ZqL
Z+S1e~~
X0]5I0YP
X}]g;|~SN
-+ Mh('K
我写的一个用于分页的类,用了泛型了,hoho J<ZG&m362p
wB%;O `Oh
java代码: (!diPwcv
!u%XvxJwDb
M_#^zo
"x
package com.intokr.util; :>, m$XO
qoJ<e`h}
import java.util.List; sKL"JA
T
GuRJ
/** bqm%@*fZo
* 用于分页的类<br> Q+^ "v]V`d
* 可以用于传递查询的结果也可以用于传送查询的参数<br> >Te h ?P
* jRSY`MU}t+
* @version 0.01 {'q(a4
* @author cheng a^Lo;kHY
*/ 3rVWehCv
public class Paginator<E> { ~&Y%yN^
privateint count = 0; // 总记录数 "I^pb.3
privateint p = 1; // 页编号 9
IY1"j0O
privateint num = 20; // 每页的记录数 e4Jx%v?_P
privateList<E> results = null; // 结果 qM0Df0$?x
"P8cgj C
/** *d,Z?S/
* 结果总数 iea7*]vW
*/ MDOP2y`2i
publicint getCount(){ ?89_2W
return count; Iq:
G9M
} aX(Y
`g)|
WRfhxl
publicvoid setCount(int count){ )W$@phY(I
this.count = count; aA&}=lm
} >iFi~)i_4y
@N+6qO}
/** e:zuP.R
* 本结果所在的页码,从1开始 z)]Br1
* $ 2PpG|q
* @return Returns the pageNo. jL9to6 Hmr
*/ #H/suQZN"g
publicint getP(){ K._*
~-A
return p; j+QE~L
} zFeo8S
"gGv>]3
/** &{H LYxh
* if(p<=0) p=1 0N4+6k|
* |;(0]
* @param p Fd/.\s
*/ +C){&/=#
publicvoid setP(int p){ 3eJ"7sftW
if(p <= 0) <B3$ODGJp
p = 1; /yO|Q{C}M8
this.p = p; LKe~
} v* /}s :a
f%5 s8)
/** i4^1bd
* 每页记录数量 23~KzC
*/ 2C_/T8
publicint getNum(){ [ _wenlkm
return num; ,T\)%q
} a>XlkkX
;Vh5nO
/** 8^|lsB}x?
* if(num<1) num=1 a.!|A(zw
*/ j9]H~:g$d
publicvoid setNum(int num){ 0)T`&u3!
if(num < 1) DQRr(r~2Kj
num = 1; EoD[,:*
this.num = num; |B/A)(c
yV
} b Q6<R4
F F7
/** n%1I}?$fO
* 获得总页数 6Om)e=gU/
*/ ?ta(`+"
publicint getPageNum(){ pz]#/Ry?
return(count - 1) / num + 1; v<c@bDZ>
} A,'JmF$d
#Kd^t=k
/** 3'D<'S}[
* 获得本页的开始编号,为 (p-1)*num+1 $X%'je
*/ sGdlS&08(
publicint getStart(){ }"CX`
return(p - 1) * num + 1; R x>>0%e.
} NHjZ`=Js
pk,]yi,ZF
/** I"1H]@"=
* @return Returns the results. fXJbC+
*/ !?u{2D
publicList<E> getResults(){ quEP"
return results; C+=8?u<
} ~p0M|
R<GnPN:c
public void setResults(List<E> results){ 1>"[b8a/
this.results = results; 2y0J~P! I
} QFS5PZ
-lNq.pp3-$
public String toString(){ _R 6+bB$
StringBuilder buff = new StringBuilder {+V]saYP
;&N=t64"
(); #-*#? -
buff.append("{"); 5!pof\/a
buff.append("count:").append(count); l#;DO9
buff.append(",p:").append(p); tin5.N)"z
buff.append(",nump:").append(num); l9eCsVQ~V
buff.append(",results:").append ~dFdO7
g} /efE
(results); c{X:0man
buff.append("}"); 6?C|pO
return buff.toString(); SZhW)0
} I\DH
7ZsBYP8%
} %gb4(~E+N
xR`W9Z5
x&kM /z?/