Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [ne4lWaE<y
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f]5bAs
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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 >g93Bj*
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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 Aid{PGDk
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分页支持类: `iIYZ3i
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java代码: v1 oS f
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package com.javaeye.common.util; V%ykHo
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import java.util.List; [Bpgb57En
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publicclass PaginationSupport { )_.@M '?
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publicfinalstaticint PAGESIZE = 30; S~/iHXm
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privateint pageSize = PAGESIZE; x6,S#p
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privateList items; = "c
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privateint totalCount; _E'M(.B<
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privateint[] indexes = newint[0]; (: ZOoL
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privateint startIndex = 0; "t"dz'
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public PaginationSupport(List items, int sur2Mw(M"
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totalCount){ ,=6Eju#P
setPageSize(PAGESIZE); r*+9<8-ZX<
setTotalCount(totalCount); &% M^:WT
setItems(items); 0U`Ic_.
setStartIndex(0); Jz%&-e3
} B}P,sFghw
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public PaginationSupport(List items, int tinN$o
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totalCount, int startIndex){ gdCU1D\
setPageSize(PAGESIZE); <,rjU*"
setTotalCount(totalCount); {b/AOR
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setItems(items); Z"!C
setStartIndex(startIndex); y-sQ"HPN
} g4Hq<W"
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public PaginationSupport(List items, int &nz1[,
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totalCount, int pageSize, int startIndex){ m"x~Fjvd
setPageSize(pageSize); k9R1E/;
setTotalCount(totalCount); ' R=o,=
setItems(items); &I!2gf
setStartIndex(startIndex); NoYu"57\
} `+zr PpX
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publicList getItems(){ Xd|5{
return items; @KS:d\l}U
} ;WGY)=-gv
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publicvoid setItems(List items){ l0Pg`wH,
this.items = items; u:,B"!
} a~XNRAh
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publicint getPageSize(){ Nr(WbD[T
return pageSize; 8sbS7*#
} m,up37-{
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publicvoid setPageSize(int pageSize){ #4cuNX5m%
this.pageSize = pageSize; 1km=9[;w'
} %0u7pk
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publicint getTotalCount(){ !J2Lp
return totalCount; d[$1:V
} ^R<= }
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publicvoid setTotalCount(int totalCount){ 9Hc#[Ml
if(totalCount > 0){ k8*=1kl"
this.totalCount = totalCount; 8g0& (9<)
int count = totalCount / gJF;yW4
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pageSize; Nxt/R%(
if(totalCount % pageSize > 0) #x%O0
count++; {UPIdQ'g
indexes = newint[count]; HQUL?URt
for(int i = 0; i < count; i++){ 41C=O@9m
indexes = pageSize * KR522YW
;\&7smE[
i; T Z>z5YTv
} ^d2g"L
}else{ <XLATS8Y
this.totalCount = 0; |Xu7cCh$me
} dG)A-qbV
} 9td(MZ%i~N
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publicint[] getIndexes(){ f%|g7[
return indexes; GuS3O)6Sg
} BM3)`40[]
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publicvoid setIndexes(int[] indexes){ XM=`(e
o
this.indexes = indexes; 94lmsE
} W&p-Z"=)
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publicint getStartIndex(){ _@RW7iP>
return startIndex; cdGl[dQ/
} ]kKsGch
mV4} -
publicvoid setStartIndex(int startIndex){ Icr'l$PE
if(totalCount <= 0) X G^
this.startIndex = 0; h|-r t15
elseif(startIndex >= totalCount) $u"K1Q3
this.startIndex = indexes [Q$"+@jw
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[indexes.length - 1]; b<7.^
elseif(startIndex < 0) .[_&>@bmrP
this.startIndex = 0; 5GRN1Aov<
else{ nC*/?y*9
this.startIndex = indexes k~hL8ZT[
> voUh;L
[startIndex / pageSize]; 4^i*1&"
} zf S<X
} eVlI:yqppj
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publicint getNextIndex(){ x)GoxH~#
int nextIndex = getStartIndex() + #IXQ;2%E
\Lc]6?,R
pageSize; }0!\%7-Q
if(nextIndex >= totalCount) 8t7hN?,t
return getStartIndex(); 9GGBJTk-
else yT,UM^'
return nextIndex; N CsUC
} r%a$u%)oD
+X- k)9
publicint getPreviousIndex(){ ![V<vIy
int previousIndex = getStartIndex() - +0a',`yc
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pageSize; Ri3m438
if(previousIndex < 0) $Z,+aLmb
return0; mee-Qq:}
else ?O3G
return previousIndex; hFjW.~B
} @Ab<I
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} G.N3R
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抽象业务类 Op0
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java代码: \"*l:x-u
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/** aL`pvsnF
* Created on 2005-7-12 /bb4nM_E/
*/ bH.">IV
package com.javaeye.common.business; %NBD^gF
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import java.io.Serializable; msCAC*;,
import java.util.List; p\HXE4d'
m$ JQ[vgh
import org.hibernate.Criteria; y^XwJX-f
import org.hibernate.HibernateException; 6SmSu\lgV
import org.hibernate.Session; 0<)8
?ow
import org.hibernate.criterion.DetachedCriteria; 4VooU [Ka(
import org.hibernate.criterion.Projections; vS0P]AUo
import H;CGLis
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org.springframework.orm.hibernate3.HibernateCallback; HOw][}M_w
import (PNvv/A
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org.springframework.orm.hibernate3.support.HibernateDaoS Ff,M~zn
s)N1@RBR
upport; 7OZs~6(
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import com.javaeye.common.util.PaginationSupport; x?%vqg^r
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public abstract class AbstractManager extends <ya3|ycnS
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HibernateDaoSupport { >Kr,(8rA
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privateboolean cacheQueries = false; 87HVD Di
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privateString queryCacheRegion; a@7we=!
"[8](3\v
publicvoid setCacheQueries(boolean tSm|U<
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cacheQueries){ }:BF3cH> 0
this.cacheQueries = cacheQueries; IlE!
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} kxdLJ_
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publicvoid setQueryCacheRegion(String !~Z L
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queryCacheRegion){ _Y0o\0B
this.queryCacheRegion = ="u(o(j"
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queryCacheRegion; Sd)D-S
} jeW0;Cz
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publicvoid save(finalObject entity){ X{ Nif G
getHibernateTemplate().save(entity); A$
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} L*5&hPU
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publicvoid persist(finalObject entity){ u'N'<(\k
getHibernateTemplate().save(entity); B@F 1!8l
} L7KHs'c*
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publicvoid update(finalObject entity){ 3*;{C|]S
getHibernateTemplate().update(entity); weu'<C
} bT>^%
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publicvoid delete(finalObject entity){ K=~h1qV:
getHibernateTemplate().delete(entity); b\^.5SEw
} /fD)/x
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publicObject load(finalClass entity, 4];NX
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finalSerializable id){ p<![JeV
return getHibernateTemplate().load wRuJein#
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(entity, id); zX5p'8-
} d8x$NW-s
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publicObject get(finalClass entity, O<+C$J|
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finalSerializable id){ v5*SoUOF
return getHibernateTemplate().get 1.';:/~(
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(entity, id); Bg#NB
} VE GUhI/d
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publicList findAll(finalClass entity){ O|OPdD
return getHibernateTemplate().find("from 7lh%\
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" + entity.getName()); `j<'*v
zo
} ?5->F/f&
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publicList findByNamedQuery(finalString e0hT
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namedQuery){ 3rWqt
return getHibernateTemplate rL%xl,cn<
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().findByNamedQuery(namedQuery); [szwPNQ_
} CUYp(GU
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publicList findByNamedQuery(finalString query, ."H5.'
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finalObject parameter){ Gud!(5'
return getHibernateTemplate #4|?;C)u\
9,9( mbWJv
().findByNamedQuery(query, parameter); v=/V<3
} |g7E*1Ie
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publicList findByNamedQuery(finalString query, ^%_LA't'R
on(W^ocnD
finalObject[] parameters){ L
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return getHibernateTemplate kp0>8rkF
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().findByNamedQuery(query, parameters); +C+3DwN
} zL>nDnL 4
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publicList find(finalString query){ F 6SIhf.;
return getHibernateTemplate().find 'T.> oP0>
kDm=Cjxv
(query); z~X] v["d
} K7y}R%QF
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publicList find(finalString query, finalObject bb#w]!q
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parameter){ 6%5A&&O(b
return getHibernateTemplate().find NcPzmW{#;g
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(query, parameter); 6bU/IVP
} N-5lILuJJ
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public PaginationSupport findPageByCriteria v[~ U*#i
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(final DetachedCriteria detachedCriteria){ }]f)Fz
return findPageByCriteria .&L#%C
0tl
(detachedCriteria, PaginationSupport.PAGESIZE, 0); *ZY{^f
} 3<Cd>o.
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public PaginationSupport findPageByCriteria c[Y7tj%y
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(final DetachedCriteria detachedCriteria, finalint H p1cVs
; xs?^N|
startIndex){ |_2O:7qe
return findPageByCriteria `!rHH
c !5OK4+Z
(detachedCriteria, PaginationSupport.PAGESIZE, 0w\gxd~'
[.0R"|$sy+
startIndex); n RXf \*"3
} (3_2h4O
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public PaginationSupport findPageByCriteria BI}>"',
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(final DetachedCriteria detachedCriteria, finalint :yw0-]/DD
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pageSize, (?~F}u
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finalint startIndex){ cU*7E39
return(PaginationSupport) ogPxj KSI
Kr8p:$D};
getHibernateTemplate().execute(new HibernateCallback(){ %Uuhi&PA-l
publicObject doInHibernate =:#$_qR
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(Session session)throws HibernateException { CjIkRa@!x
Criteria criteria = Prr<:q
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detachedCriteria.getExecutableCriteria(session); Q%@l`V)Rs
int totalCount = 8 v&5)0u
0xH$!?{b
((Integer) criteria.setProjection(Projections.rowCount 5vY1 XZt{
&?x^I{j
()).uniqueResult()).intValue(); :y]l`Mo -
criteria.setProjection _{-GR -
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(null); =<FFFoF*C_
List items = )%)?M
*
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criteria.setFirstResult(startIndex).setMaxResults 0Wk}d(f
d~YDg{H
(pageSize).list(); O^
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PaginationSupport ps = `qX'9e3VP+
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new PaginationSupport(items, totalCount, pageSize, 2\m+
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startIndex); !a?o9<V
return ps; C[&Lh_F\
} W"z!sf5U
}, true); #{<Jm?sU
} 2,dGRf
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public List findAllByCriteria(final R1?g6. Mq
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DetachedCriteria detachedCriteria){ l HZf'P_Wx
return(List) getHibernateTemplate o#E
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().execute(new HibernateCallback(){ ?^k-)V
publicObject doInHibernate T w/CJg
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(Session session)throws HibernateException { U4M!RdG
Criteria criteria = zYF'XB]4
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detachedCriteria.getExecutableCriteria(session); E]"ePdZZ/
return criteria.list(); G+}|gG8
} X%39cXM C
}, true); Hn:%(Rg=aW
} XPb7gd"%W
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public int getCountByCriteria(final C9({7[k^%
hX~IZ((Hi8
DetachedCriteria detachedCriteria){ !t[X/iu
Integer count = (Integer) 1\_4# @')
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getHibernateTemplate().execute(new HibernateCallback(){ c1e7h l
publicObject doInHibernate U
= T[-(:H
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(Session session)throws HibernateException { t5[{ihv~:
Criteria criteria = hm?-QVRPV
>.~^(
detachedCriteria.getExecutableCriteria(session); Ujb||(W
return jG8ihi
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criteria.setProjection(Projections.rowCount |jc87(x<
_?`3zm4
()).uniqueResult(); (;cbgHo%}
} a\^DthZ!;|
}, true); Jg|/*Or
return count.intValue(); OfY>~d
} N',]WZ}
} yn4Xi@9Pri
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/ ijj;9EB
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用户在web层构造查询条件detachedCriteria,和可选的 sd.:PE <
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ow%s_yV]R
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PaginationSupport的实例ps。 "X"DTP1b
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ps.getItems()得到已分页好的结果集
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ps.getIndexes()得到分页索引的数组 u6cWLVt
ps.getTotalCount()得到总结果数 Cz m`5
ps.getStartIndex()当前分页索引 o^7}H{AE
ps.getNextIndex()下一页索引 ^vJ08gu_W
ps.getPreviousIndex()上一页索引 3v5]L3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 !f]F'h8
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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 JzCfs<D
z`m-Ca>6
一下代码重构了。 ATH0n>)
cfa#a!Y4
我把原本我的做法也提供出来供大家讨论吧: F(}d|z@@
;sCX_`t0E
首先,为了实现分页查询,我封装了一个Page类: 03AYW)"}M
java代码: yz,ak+wp
1&U'pp|T
x>p=1(L
/*Created on 2005-4-14*/ <fWho%eOK
package org.flyware.util.page; /Y%) Y
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/** .lTU[(qwu
* @author Joa +TA(crD
* q1`uS^3`
*/ %\%1EZQ%
publicclass Page { <iv9Mg}
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/** imply if the page has previous page */ =}u;>[3
privateboolean hasPrePage; Ui'~d(F
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/** imply if the page has next page */ pBh[F5
privateboolean hasNextPage; J6rXbui$
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/** the number of every page */ H[fD
>
privateint everyPage; zxTm`Dh;[
\d]&}`'4{f
/** the total page number */ 9F ).i
privateint totalPage; wW]|ElYR=
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/** the number of current page */ nakhepLN
privateint currentPage; uA*Op45
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/** the begin index of the records by the current R qOEQ*k
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query */ J rYpZ.Nh
privateint beginIndex; VBBqoyP
h
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/** The default constructor */ l?Bv9k.^?
public Page(){ 3eFD[c%mN
ir3iW*5k
} Jel%1'Dc^
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/** construct the page by everyPage m-7^$
* @param everyPage VS1gg4tCv
* */ z| i$eF;x3
public Page(int everyPage){ HC+(FymV
this.everyPage = everyPage; $BkdC'D
} 4VD'<`R[
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/** The whole constructor */ eNi.d;8F
public Page(boolean hasPrePage, boolean hasNextPage, %ktU 51o
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int everyPage, int totalPage, _av%`bb&z9
int currentPage, int beginIndex){ x]Q+M2g?
this.hasPrePage = hasPrePage; }us%G&A2u
this.hasNextPage = hasNextPage; _dIv{L!
this.everyPage = everyPage; _H<ur?G
this.totalPage = totalPage; -Y2h vC
this.currentPage = currentPage; 'R,1Jmx
this.beginIndex = beginIndex; Hg*6I%D[So
} xGPt5l<M&
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/** 3QM.X^ANH
* @return / QSK$ZDC
* Returns the beginIndex. 3[-L'!pOX3
*/ ?v8B;="#w
publicint getBeginIndex(){ VL7zU->
return beginIndex; aG`G$3 _wx
} ) l0=jb
j;J4]]R;o
/** 2Q-kD?PO,
* @param beginIndex `+k&]z$m
* The beginIndex to set. ZWh:&e(
*/ .'L@$]!G
publicvoid setBeginIndex(int beginIndex){ 6(<M.U_ft
this.beginIndex = beginIndex; b?h"a<7
} r6*0H/*
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/** D{PO!WzW
* @return u` R
* Returns the currentPage. xa5I{<<U
*/ D.)R8X
publicint getCurrentPage(){ ,hYUxh45
return currentPage; D9 ,~Fc
} d=Q0/sI&
[;h@q}
/** - "h
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* @param currentPage q}1AV7$Ai
* The currentPage to set. i*nNu-g
*/ \
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publicvoid setCurrentPage(int currentPage){ Y]^[|e8
this.currentPage = currentPage; M5[AA/@
} "72
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/** $NT{ssh
* @return NcB^qv
* Returns the everyPage. ){5$8
*/ Rb',"` 7
publicint getEveryPage(){ ceyZ4M
return everyPage; CP["N(fF
} bUU_NqUf*3
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fk;
/** .
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* @param everyPage jbMzcn~ehI
* The everyPage to set. pn{Nk1Pl
*/ Ym2![FC1
publicvoid setEveryPage(int everyPage){ 3'
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this.everyPage = everyPage; YDz:;Sp\
} sj0Hv d9
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/** s-3vp
* @return mst-:F[h
* Returns the hasNextPage. 2PAotD4+I
*/ C[|jJ9VE,
publicboolean getHasNextPage(){ 6psK2d0
return hasNextPage; }gGcYRT
} /2~qm/%Q
vsRn\Y
/** ~eA7:dZLb
* @param hasNextPage A@f`g[q
* The hasNextPage to set. 305()
*/ jaFBz&P/#
publicvoid setHasNextPage(boolean hasNextPage){ NcwZ_*sqj
this.hasNextPage = hasNextPage; W7_X=>l
} #L`@["
j2k,)MHu!x
/** QUH USDT
* @return <t.yn\G-w
* Returns the hasPrePage. m!tB;:6
*/ Go=MG:`
publicboolean getHasPrePage(){ 3l-8TR
return hasPrePage; <;=?~QK%-
} W(9-XlYKE
=M*31>"I0
/** E}b"
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* @param hasPrePage >
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* The hasPrePage to set. tF
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*/ mXAX%M U
publicvoid setHasPrePage(boolean hasPrePage){ ;Ze}i/l
this.hasPrePage = hasPrePage; VNp[J'a>VZ
} DrC4oxS 1
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/** Kn?>XXAc
* @return Returns the totalPage. oDrfzm|[Y
* !w(J]<
*/ ;mjk`6p
publicint getTotalPage(){ [K9l>O
return totalPage; p>Qzz`@e
} -V%"i,t
4`7N}$j#,
/** s%1 O}X$c
* @param totalPage qm{(.b^
* The totalPage to set. ^"(CZvq
*/ +>M^p2l*&
publicvoid setTotalPage(int totalPage){ |'aGj
this.totalPage = totalPage; ~*79rDs{
} g~rZ=
:54ik,l
} LkK%DY
HcavA{H
}i ^]uW*h
B8:G1r5G/
gp`$/ci
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 ~a^mLnY@
YNRpIhb
个PageUtil,负责对Page对象进行构造: f(6`5/C
java代码: /q^)thJ~
$BXZFC_1S
qRZv[T%*Q
/*Created on 2005-4-14*/ +vIpt{733
package org.flyware.util.page; wqk D
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}6)J
import org.apache.commons.logging.Log; @@-n/9>vs
import org.apache.commons.logging.LogFactory; jAie[5
- 0R5g3^*/
/** aY@]mMz\
* @author Joa EZ:pcnL{
* ?
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*/ %JF^@\E!|
publicclass PageUtil { p.A_,iE
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privatestaticfinal Log logger = LogFactory.getLog ,&e0~
w9<<|ZaU
(PageUtil.class); xQ+UZc
X ^8@T
/** ^~9fQJNs
* Use the origin page to create a new page BKvX,[R2
* @param page L-?
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* @param totalRecords zkt`7Pg;J
* @return v[{g"C
*/ }E0~'
publicstatic Page createPage(Page page, int *:gx1wd
t~]n"zgovz
totalRecords){ rofj&{w
return createPage(page.getEveryPage(), `u$
Rd
H=RzY-\a%
page.getCurrentPage(), totalRecords); X'Q?Mh
} ]Wr2I M
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/** %A64AJZ
* the basic page utils not including exception KSDz3qe
b+Sq[
handler `?E|frz[
* @param everyPage `?f6~$1
* @param currentPage +O"!*
* @param totalRecords Zgy~Y0Di
* @return page _N)/X|=~s
*/ tg-U x
publicstatic Page createPage(int everyPage, int C@d*t?
fIe';a
currentPage, int totalRecords){ '5V}Z3zJ/
everyPage = getEveryPage(everyPage); `yF6-F
currentPage = getCurrentPage(currentPage); .j^tFvN~L
int beginIndex = getBeginIndex(everyPage, iZY4+
X
(+uM |a
currentPage); PkX4 !
int totalPage = getTotalPage(everyPage, |ecK~+
0,~||H{
totalRecords); kb3>q($
boolean hasNextPage = hasNextPage(currentPage, +q n[F70}
Cm@rXA/
totalPage); 3r^Ls[ey
boolean hasPrePage = hasPrePage(currentPage); S!WG|75B
#O 2g]YH
returnnew Page(hasPrePage, hasNextPage, bpP-wA^Hd
everyPage, totalPage,
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currentPage, X})5XYvA*
^Gi9&fS,
beginIndex); 3PkVMX
} E$SYXe [,
2_T2?weD5
privatestaticint getEveryPage(int everyPage){ Ig&H0S
return everyPage == 0 ? 10 : everyPage; WbJ|]}hJ\
} Nm$Ba.Rg
5"sd
privatestaticint getCurrentPage(int currentPage){ +pUG6.j%
return currentPage == 0 ? 1 : currentPage; W4Z8U0co
} +MZsL7%
dCA| )
privatestaticint getBeginIndex(int everyPage, int 9K!kU6Gh
.`p,pt;
currentPage){ _E %!5u
return(currentPage - 1) * everyPage; 5PY4PT=G
} ;k?Z,M:
'Em3;`/C*+
privatestaticint getTotalPage(int everyPage, int 7N:3
uA-1VwW+N
totalRecords){ S)LvYOOB@
int totalPage = 0; nA*Udrcn
4y*"w*L
if(totalRecords % everyPage == 0) =/5^/vwgY
totalPage = totalRecords / everyPage; H 48YX(HI
else 5Ve`j,`=<
totalPage = totalRecords / everyPage + 1 ; hGU
m7
*kYJwO^
return totalPage; TWSqn'<E
} cMs8D
ygK@\JHn
privatestaticboolean hasPrePage(int currentPage){ 'p FK+j
return currentPage == 1 ? false : true; :+_uyp2V
} E] 6]c!2:
QM('bbN
privatestaticboolean hasNextPage(int currentPage, 1.0:
!;3hN$5
int totalPage){ Y`N w E
return currentPage == totalPage || totalPage == ?e{hidg
$E/N
0 ? false : true; h+rW%`B
} C5Vlqc;
d`gKF
V15/~
} ^(kmF UV,Z
w#v-h3XcF
?K\r-J!Y
ZH)Jq^^RI
^HhV?Iqg
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 n\ 'PNB
E3LEeXcLS
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 %W}YtDf\
hbdB67,
做法如下: Mfn^v:Q#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 T)MX]T
{S@gjMuN
的信息,和一个结果集List: 6E@TcN~,!
java代码: A$g'/QM
j/t)=c
S
awf]/
/*Created on 2005-6-13*/ :F8h}\a*
package com.adt.bo; \G0YLV~>P
dQn,0
import java.util.List; =AcK9?%5
}}qY,@eeX
import org.flyware.util.page.Page; |2E:]wT}qg
ToK=`0#LNK
/** +iqzj-e&e[
* @author Joa 1B#iJZ}
*/ `@xnpA]l
publicclass Result { f
AY(ro9Q(
^
Paf -/
private Page page; B&QEt[=s
$D='NzE/
private List content; *ESi~7;#
aX,6y1
/** KV 8Ok
* The default constructor w5 #;Lm
*/ %I=/
y
public Result(){ wRdN(`;v
super(); EK.n
$
} EfB.K}b^
!hFzIp
/** eZ]>;5
* The constructor using fields j[Jwa*GQP
* :HM~!7e
* @param page .6!cHL3ln
* @param content KVevvy)W
*/ 2]y Hxo/6
public Result(Page page, List content){ \[G"/]J
this.page = page; ;qO3m-(d
this.content = content; c|@OD3w2lM
} f?r{Q
AJ>$`=
/** ]VR79l
* @return Returns the content. #<y/m*Ota
*/ #_Zkke~{
publicList getContent(){ QFK'r\3pU
return content; p//mVH%
} 4p7j"d5
AC\y|X8-
/** o5['5?i} /
* @return Returns the page. ;eJ|)*
*/ &_q8F,I \<
public Page getPage(){ (}5};v
return page; mPF<2:)wv
} 4B9D
9mW
/** O2":)zU.
* @param content z6Fl$FFP
* The content to set. ZA&bp{}D
*/ mBEMwJ}O`
public void setContent(List content){ ]Exbuc
this.content = content; KjMwrMgC
} n<P&|RTZ
qm<-(Qc(W
/** R|k:8v{V=
* @param page P v=]7>e
* The page to set. f9OY>|a9
*/ Y[|9
+T
publicvoid setPage(Page page){ ahdwoB
this.page = page; +f$
{r7
} 1,:QrhC
} ,k1ns?i9KH
p-m\0tQ
iMv):1p>8
<00nu'Ex1v
]*U+nG
2. 编写业务逻辑接口,并实现它(UserManager, \?wKs
1h|qxYO
UserManagerImpl) Pc`)D:/}R
java代码: p(-EtxP
\irKM8]LJ
gil:SUW1r
/*Created on 2005-7-15*/ ecx_&J@D
package com.adt.service; /3.;sS]B
He$v'87]
import net.sf.hibernate.HibernateException; l*(L"]
BUdO:fr
import org.flyware.util.page.Page; }
@
[!%hE
AQtOTT$
import com.adt.bo.Result; KzX)6|g{"
i03=Af3
/** mq}UUk@
* @author Joa uP$i2Cy
*/ h+7U'+|%A
publicinterface UserManager { j >`FZKxp
G0kF[8Am
public Result listUser(Page page)throws G O"E>FyB
$2Awp@j
HibernateException; 8#R%jjr%T
G({5Lj gW
} QkWEVL@uM
w#_7,*6]
q Y!LzKM0
W4qnXD1n
^$mCF%e8H
java代码: JvEW0-B^l,
3UF^Ff<wo
EuA352x
/*Created on 2005-7-15*/ ?9 W2ax-4
package com.adt.service.impl; eoFG$X/PO
xnJ#}-.7
import java.util.List; z:N?T0b(
aO}p"-'
import net.sf.hibernate.HibernateException; mI\[L2x
>l=jJTJ;q
import org.flyware.util.page.Page; rLY I\
import org.flyware.util.page.PageUtil; h#Mx(q
C?MKbD=K
import com.adt.bo.Result; zlB[Eg^X
import com.adt.dao.UserDAO; v9!]/]U^
import com.adt.exception.ObjectNotFoundException; *>!-t
import com.adt.service.UserManager; 8Ht=B,7T
J*zQ8\f=}
/** IF@vl
* @author Joa 5!wjYQt3
*/ cmYzS6f,7
publicclass UserManagerImpl implements UserManager { TwF.UL@G%
[,;O$j}
private UserDAO userDAO; ONZ(0H{ 1$
~]Av$S
/** Bs|#7mA[
* @param userDAO The userDAO to set.
hhhxsGyv
*/ @$CPTv3e
publicvoid setUserDAO(UserDAO userDAO){ KZ1m2R}'
this.userDAO = userDAO; *v: .]_;
} 6ZwQ/~7H
8M,z#DF
/* (non-Javadoc) bSQj=|h1
* @see com.adt.service.UserManager#listUser DjiI*HLNR
ILiOEwHS7F
(org.flyware.util.page.Page) >)Bv>HM
*/ t?b@l<,s
public Result listUser(Page page)throws <[T{q
|*
$VP\Ac,!
HibernateException, ObjectNotFoundException { I)9,
int totalRecords = userDAO.getUserCount(); VV#'d
if(totalRecords == 0) #)i+'L8
throw new ObjectNotFoundException '
QjJ^3A
#s#BYbF
("userNotExist"); *5 \'$;Rg
page = PageUtil.createPage(page, totalRecords); B/mfm 7
List users = userDAO.getUserByPage(page); D(Q]ddUi'
returnnew Result(page, users); naA8RD5/
} sO!m,pK(
~Y;Z5e=
} _;/+8=
(]VY==t~
7VdxQ T
1. <g C
F7/%,vf
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 uJ fXe
]l3Y=Cl
询,接下来编写UserDAO的代码: T-iQ!D~
3. UserDAO 和 UserDAOImpl: meXwmO
java代码: 32y 9r z
><.*5q
cBU3Q<^
/*Created on 2005-7-15*/ ]r%fAmj
package com.adt.dao; 3qDbfO[
Ls3r( Tf
import java.util.List; &m]jYvRc
;?TM_%>
import org.flyware.util.page.Page; V&/Cb&~Uw
e~9g~k]s
import net.sf.hibernate.HibernateException; FF7?|V!Q
O%aHQL%Sz
/** h2= wC.
* @author Joa [@3.dd
*/ ]US!3R^
publicinterface UserDAO extends BaseDAO { AM#s2.@
:QHh;TIG=<
publicList getUserByName(String name)throws ,g3n/'rP%
!/!Fc'A
HibernateException; CL?=j| Ea
&Z9rQH81f>
publicint getUserCount()throws HibernateException; Po.by~|
e?
|4O<@
publicList getUserByPage(Page page)throws !CY*SGO
ttt4h
HibernateException; !9.\A:G
"5Z5x%3I
} G_WHW(8
W@%g_V}C*
o3NB3@uj<
_Kh8
<$h
mtw{7E
java代码: IJ:JH=8
V@EyU/VJ
-zzT:C
/*Created on 2005-7-15*/ 2E!Q5 l!j
package com.adt.dao.impl; nQg_1+
LY#V)f
import java.util.List; _?K,Jc8j.
d69dC*>
import org.flyware.util.page.Page; {h.j6
dYlVJ_0Zr
import net.sf.hibernate.HibernateException; dl`{:ZR S
import net.sf.hibernate.Query; 9A|9:OdG1
)t:8;;W@Ir
import com.adt.dao.UserDAO; 2r]o>X
:2XX~|
/** sv#b5,>9
* @author Joa s"2+H}u
*/ WY5HmNX3E
public class UserDAOImpl extends BaseDAOHibernateImpl i'1MZ%.
I=
cayR
implements UserDAO { PIoBK CJ
^V]IPGV
/* (non-Javadoc) -[h|*G.J
* @see com.adt.dao.UserDAO#getUserByName M=4b
TZ}y%iU:mB
(java.lang.String) m}>Q#IVZ
*/ A>RK3{7
publicList getUserByName(String name)throws ?V(+Cc
6!;D],,"#.
HibernateException { k\g:uIsv$
String querySentence = "FROM user in class hDBo
XIK
QR<<O
com.adt.po.User WHERE user.name=:name"; xX Dj4j,
Query query = getSession().createQuery [81q 0@
[F{P0({%?
(querySentence); OsRizcgdA
query.setParameter("name", name); UgZL<}
return query.list(); g'2;///
} F%O+w;J4
<,U$Y>
/* (non-Javadoc) mHH>qW{`
* @see com.adt.dao.UserDAO#getUserCount() .*J /F$
*/ PR,8c
publicint getUserCount()throws HibernateException { VtGZB3
int count = 0; `lt[Q>Z
String querySentence = "SELECT count(*) FROM : JSuC
kE[R9RS!
user in class com.adt.po.User"; WYkh'sv >
Query query = getSession().createQuery PY&mLux%
A!}Ps"Z
(querySentence); i|28:FJA
count = ((Integer)query.iterate().next 9kbczL^Y
6fCHd10!
()).intValue(); }'n]C| gZ
return count; 2R;#XmKS
} x,fL656t
WSGho(\
/* (non-Javadoc) 0Fsa&<{6?
* @see com.adt.dao.UserDAO#getUserByPage .S4%Q9l
GLMpWD`Wo
(org.flyware.util.page.Page) }KEr@h,N
*/ *u < ZQq
publicList getUserByPage(Page page)throws +/" \.wYv
,K|UUosS-#
HibernateException { 2zuQeFsK
String querySentence = "FROM user in class Yvu?M8aK!
,/!^ZS*
com.adt.po.User"; "z_},TCy
Query query = getSession().createQuery rFp>A`TJ
?0qP6'nWx
(querySentence); \m:('^\6o
query.setFirstResult(page.getBeginIndex()) ^uPg71r:
.setMaxResults(page.getEveryPage()); WF2t{<]^e
return query.list(); Dt iM}=:
} 0]^gT'
o%0To{MAF-
} oa`7ClzD
~@T`0W-Py
`}rk1rl6
K6|R ;r5e{
8NTE`l=>/
至此,一个完整的分页程序完成。前台的只需要调用 Qd>\{$N
/!`xqG#
userManager.listUser(page)即可得到一个Page对象和结果集对象 JY~CMR5#.O
s#(%u t
的综合体,而传入的参数page对象则可以由前台传入,如果用 H5o=nWQ6e
QV4FA&f&
webwork,甚至可以直接在配置文件中指定。 wzBw5nf\
py'xBi6}v
下面给出一个webwork调用示例: 'rA(+-.M;
java代码: 62K#rRS
bfy=
qVjMflVoay
/*Created on 2005-6-17*/ h
9}x6t,
package com.adt.action.user; Y%>u.HzL
Pw5[X5.DX
import java.util.List; &
x_
#zN]
Eh$1piJG
import org.apache.commons.logging.Log; BO%'/2eV
import org.apache.commons.logging.LogFactory; -=ZDfM
import org.flyware.util.page.Page; 0Q)YZ2
k|U2Mp
import com.adt.bo.Result; H6U5-
import com.adt.service.UserService; yhs:.h
import com.opensymphony.xwork.Action; OB*V4Yv
{<?8Y
/** .N`*jT
* @author Joa T)',}=
*/ 9Hd_sNUu\
publicclass ListUser implementsAction{ y*p02\)
IIAmx[ b
privatestaticfinal Log logger = LogFactory.getLog L|6I
Z[eWey_
(ListUser.class); 2(m#WK7>F
sz%_9;`dpL
private UserService userService; mkl^2V13~
cv7:5P
private Page page; fPPmUM^C9
T''<y S
privateList users; NB+/S ;`
m(0X_&&?z
/* uL^`uI#I
* (non-Javadoc) 7!\zo mx
* |=MhI5gsx
* @see com.opensymphony.xwork.Action#execute() vo%"(!
*/ 5L_`Fw\l
publicString execute()throwsException{ v G9>e&Be
Result result = userService.listUser(page); 7R# }AQ
page = result.getPage(); HxcL3Bh$~}
users = result.getContent(); M>}_2G]#F
return SUCCESS; Qkhor-f0
} +'nMy"j1
1aCpeD4|)
/** q'TIN{\.{
* @return Returns the page. &HtTh {
*/ o"_'cNAz
public Page getPage(){ W|y;Kxy
return page; 5pK
_-:?
} 0G0(g,3p
_uXb>V*8
/** ={+8jQqi1
* @return Returns the users. 9C0#K\
*/ 't5`Ni
publicList getUsers(){ i'4.w?O Z
return users; R<(xWH
} 4 Tw~4b
>[;=c0(
/** $*T?}r>
* @param page C,GZ
* The page to set. t,IOq[Vtk
*/ 8ZLHN',
publicvoid setPage(Page page){ xV
2C4K
this.page = page; 7D4tuXUq2
} NzTF2ve(
4d-(:
/** egURRC!
* @param users v"Ax'()
* The users to set. C/'w
*/ 44|tCB`
publicvoid setUsers(List users){
>]~|Nf/i
this.users = users; &I[` .:NJ
} zn7)>cQ905
bI8uw|c
/** ,isjiy
J
* @param userService S#$Kmm
|
* The userService to set.
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*/ /jGV[_Q=P
publicvoid setUserService(UserService userService){ >#k-
~|w
this.userService = userService; ^YropzHZ4E
}
o?m/
} h /^bRs`;
f-71`Pyb
PMV,*`"9"A
RtzSe$O
PP>6
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, LO>42o?/i
WmN(
(
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 2J8:_Ql3I
u+KZ. n/
么只需要: :dAd5v2f
java代码: q!?*M?Oz
a6^_iSk
2vX $:4
<?xml version="1.0"?> 8W?dWj
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >m..
oPM*VTMA
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 13`Mt1R
|K06H
?6X
1.0.dtd"> Zd-6_,r
2wHbhW[
<xwork> y& 1@d+Lf
nS*Y+Q^9a
<package name="user" extends="webwork- % hvK;B?Y|
Jk6}hUH,
interceptors"> \m
GY'0
T9H*]LxK
<!-- The default interceptor stack name L/V^ #$
});Rjg
--> 7-!n-
<default-interceptor-ref DQm%=ON7
e)g&q'O
name="myDefaultWebStack"/> VL$
T
$
VP1(C
<action name="listUser" hW<v5!,
@qq"X'3t
class="com.adt.action.user.ListUser"> uMS+,dXy
<param u0 tlf
gJ'pwSA
name="page.everyPage">10</param> eY5mwJ0K
<result mV$ebFco0
ABX%oZ7[|o
name="success">/user/user_list.jsp</result> J5I@*f)l
</action> yy7(')wKO
.t5.(0Xk[A
</package> HdJ g
%BP>,E/w
</xwork> k[;)/LfhS
<\u3p3"[4
IrqM_OjC
oDz|%N2s|
E)gD"^rex
Mzp<s<BX
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 7MLLx#U
aQtd6L+ J
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 @wI>0B
89g
a+#7
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 JfIXv
MK=oGzK
0lg$zi x(
:^v Q4/,
\7r0]& _
我写的一个用于分页的类,用了泛型了,hoho 1 _?8 OU
!m+Pd.4TaB
java代码: >|E]??v
5M0Q'"`F:
L(VFzPkY%
package com.intokr.util; zVq!M-e
f\]?,
import java.util.List; <gkE,e9
alaL/p{O
/** FklR!*oL,)
* 用于分页的类<br> xR/CP.dg
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ctZ,qg*N
* m9DFnk<D
* @version 0.01 }kqh[`:
* @author cheng 3ic /xy;}
*/ >8e)V
;
public class Paginator<E> { Mw/9DrE7/
privateint count = 0; // 总记录数 A'DFY {
privateint p = 1; // 页编号 I)Xf4FS@
privateint num = 20; // 每页的记录数 ]P0%S@]
privateList<E> results = null; // 结果 &v{#yzM
#1DEZ4]jjY
/** e0zP LU}
* 结果总数 Z8#nu
*/ 7~e,"^>T
publicint getCount(){ @M5+12FYt
return count; Lt't
} Jr2yn{s=S
^v'kEsE^*
publicvoid setCount(int count){ -G~]e6:zD
this.count = count; |Ns4^2
} wtTy(j,9
.h-mFcjy
/** d m8t~38
* 本结果所在的页码,从1开始 iBSM
\ n
* 3%kUj
* @return Returns the pageNo. 4>*=q*<V5E
*/ .|
4P
:r
publicint getP(){ 4v\HaOk
return p; 9Da{|FyrD
} gwoe1:F:J
*#T:
_
/** S hI1f
* if(p<=0) p=1 HAxLYun(3w
* mr\,"S-`
* @param p (p-q>@m
*/ Kjd3!%4mB
publicvoid setP(int p){ Qr$'Q7
if(p <= 0) e*7O!Z=O
p = 1; vB8$Qx\J
this.p = p; ,|A^ <R`
} IA2VesHb
\,Y
.5 ?
/**
8G:/f3B=
* 每页记录数量 msBoInhI
*/ nR{<xD^
publicint getNum(){ 6e-ME3!<l
return num; 41X`.
} qVC+q8
E>bkEm
/** 5whW>T
* if(num<1) num=1 r3'J{-kl
*/ v`A)GnNiN
publicvoid setNum(int num){ |OH*c3~r
if(num < 1) rmX*s}B
num = 1; Hd~g\
this.num = num; /mkT7,]
} Y)sB]!hx
)p\`H;7*V4
/** {A0jkU
* 获得总页数 YEu+kBlcQ
*/ os/h~,=
publicint getPageNum(){ fsL9d}
return(count - 1) / num + 1; @+b$43^
} f24W*#IX
9\Jc7[b
/** ]-\68b N
* 获得本页的开始编号,为 (p-1)*num+1 4z<c8
E8
*/ xMjhC;i{
publicint getStart(){ m!FuC=e
return(p - 1) * num + 1; RE>Q5#|c
} nwFBuP<LR
MQoA\
/** duG!QS:
* @return Returns the results. <P h50s4
*/ Wk%|%/:
publicList<E> getResults(){ I3Vu/&8f|
return results; Cqr{Nssu
} cq
I $9
aopPv&jY
public void setResults(List<E> results){ 5P!ZGbG
this.results = results; +e{ui +
} fd'kv
+``vnC
public String toString(){ rCPIz<
StringBuilder buff = new StringBuilder %'KRbY
Y_%:%J
(); )>ZT{eF
buff.append("{"); <XLae'R
buff.append("count:").append(count); $g>bp<9v4
buff.append(",p:").append(p); syX?O'xJ
buff.append(",nump:").append(num); r2RJb6
buff.append(",results:").append *:L"#20:R
Z<X=00,wg
(results); eK7A8\;e
buff.append("}"); y0xBNhev
return buff.toString(); >=N-P<%
} DT]4C!dh
RL`E}:V
} 8jz>^.-o
qyRN0ZB"A^
yj:@Fg-3g