Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z}|TW~J=
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 j]rXoV>
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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 9lKn%|=T
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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 W%TQYR
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分页支持类: q(,cYu
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java代码: _}D%iJg#
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package com.javaeye.common.util; F9-[%l
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import java.util.List; HN{z T&
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publicclass PaginationSupport { ^o YPyk`9
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publicfinalstaticint PAGESIZE = 30; ndw7v
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privateint pageSize = PAGESIZE; f-4.WW2FN
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privateList items; .jA\f:u#
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privateint totalCount; /be=u@KV
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privateint[] indexes = newint[0]; /t*YDWLg
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privateint startIndex = 0; _-O cc=Z
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public PaginationSupport(List items, int 3+ =I;nj
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totalCount){ vg)Z]F=t(
setPageSize(PAGESIZE); \:Za[6
setTotalCount(totalCount); h./P\eDc
setItems(items); Z.'syGuV
setStartIndex(0); =\Iu$2r`
} "k:=Y7Dx
zC=a3
public PaginationSupport(List items, int id ?"PD"%
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totalCount, int startIndex){ Ja|{1&J.
setPageSize(PAGESIZE); x r[Vp
setTotalCount(totalCount); w^HjZV
setItems(items); 5dl,co{q
setStartIndex(startIndex); "$| Zr
} $ J1f.YE
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public PaginationSupport(List items, int kccWoU,
8AL\ST51x"
totalCount, int pageSize, int startIndex){ 'c %S!$P
setPageSize(pageSize); mrM4RoO
setTotalCount(totalCount); dU_;2#3m
setItems(items); 2'|8Q\,:4Z
setStartIndex(startIndex);
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} N|K4{Frm
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publicList getItems(){ fThgK;Qy'U
return items; t
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} eGL<vX
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publicvoid setItems(List items){ QJGKQ2^ n
this.items = items; ?X9UTOx
} 86
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publicint getPageSize(){ [XR$F@o
return pageSize; fCw*$:O
} + ulagE|7
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publicvoid setPageSize(int pageSize){ N|usFqCNk^
this.pageSize = pageSize; -_N)E ))G
} I&VTW8jB
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publicint getTotalCount(){ `A@w7J'
return totalCount; "i^
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} EGVM)ur
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publicvoid setTotalCount(int totalCount){ :-T*gqj|
if(totalCount > 0){ E_T2z4lw
this.totalCount = totalCount; ;C.S3}
int count = totalCount / M@et6aud;K
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pageSize; .a'f|c6
if(totalCount % pageSize > 0) w_tJ7pz8T
count++; k[j90C5
indexes = newint[count]; ~`ny@WD9
for(int i = 0; i < count; i++){ p'_%aVm7
indexes = pageSize * qet>1<
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i; uVE.,)xz
} KngTc(^_D
}else{ mHc>"^R
this.totalCount = 0; SRIA*M.B}
} 4<dcB@v
} H,unpZ(
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publicint[] getIndexes(){ kR CQv-*
return indexes; dP?Ge}
} b?X.U}62_
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publicvoid setIndexes(int[] indexes){ pKiZ)3U
this.indexes = indexes; )Z 9E=%
} f5AjJYq1
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publicint getStartIndex(){ >{gPN"S"a
return startIndex; D"(L5jR8m@
} q;g>t5]a
ajR%c2G;
publicvoid setStartIndex(int startIndex){ ZYU=\
if(totalCount <= 0) 9vUO*D
this.startIndex = 0; fZ04!R
elseif(startIndex >= totalCount) (wIzat
this.startIndex = indexes VVH.2&`I
9{k97D/
[indexes.length - 1]; Vtc36-\1*
elseif(startIndex < 0) lO&3{dOYE
this.startIndex = 0; gVQjL+_W
else{ ;c~cet4
this.startIndex = indexes 'o|30LzYgQ
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[startIndex / pageSize]; 3bk|<7tl
} HEA#bd\
} Gj"7s8(/K|
kt`nbm|aw
publicint getNextIndex(){ ]f+ csB
int nextIndex = getStartIndex() + m'P1BLk
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pageSize; |
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if(nextIndex >= totalCount) _ZY)M
return getStartIndex(); u[nyW3MZ
else (WJ${OW
return nextIndex; pw7[y^[Qg
} ;"(foY"L
!Mi;*ZR
publicint getPreviousIndex(){ j'9"cE5_
int previousIndex = getStartIndex() - *OuStr \o
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pageSize; aW>6NDq(
if(previousIndex < 0) ^Z~;4il_F
return0; 8_T6_jL<
else nstUMr6
return previousIndex; 8\{^|y9-
} w@N
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} 035rPT7-2-
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抽象业务类 4:U?u
java代码: DGzw8|/(
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/** NH+(?TN
* Created on 2005-7-12 7)s^8+
*/ )_U<7"~0l
package com.javaeye.common.business; ;qrB\j"
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import java.io.Serializable; o7|eMe?<t
import java.util.List; ~8lwe*lNV
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import org.hibernate.Criteria; L'u\w
import org.hibernate.HibernateException; ;VWAf;U;B
import org.hibernate.Session; ;<leKcvhQ&
import org.hibernate.criterion.DetachedCriteria; Yb E-6|cz
import org.hibernate.criterion.Projections; /iX+ R@
import YCP) %}
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org.springframework.orm.hibernate3.HibernateCallback; gvLf|+m
import () j=5KDu
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org.springframework.orm.hibernate3.support.HibernateDaoS Y 'ow
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upport; eM+!Y>8Y
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import com.javaeye.common.util.PaginationSupport; ]w.;4`l*
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public abstract class AbstractManager extends ~J P=T
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HibernateDaoSupport { +(h\fm7*-
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privateboolean cacheQueries = false; ^Y'HaneoM
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privateString queryCacheRegion; _A=$oVe
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publicvoid setCacheQueries(boolean !1ED~3/X
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cacheQueries){ hC\6-
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this.cacheQueries = cacheQueries; '#&os`mQ
} @~%r5pz6
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publicvoid setQueryCacheRegion(String CY"/uSB
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queryCacheRegion){ f`;j:O
this.queryCacheRegion = 8@tPm$
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queryCacheRegion; bLwAXW2K+
} eN^qG
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publicvoid save(finalObject entity){ wbst8*$
getHibernateTemplate().save(entity); 7eiV{ tYF
} v+X)Qmzf~
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publicvoid persist(finalObject entity){ h"/<?3{
getHibernateTemplate().save(entity); Ipf=ZD
} zlEX+=3
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publicvoid update(finalObject entity){ d&+h}O
getHibernateTemplate().update(entity); LRNh@g4ei
} LL3#5AA"k|
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publicvoid delete(finalObject entity){ |563D#?cR
getHibernateTemplate().delete(entity); <kx&w(=
} zc;|fHW~O
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publicObject load(finalClass entity, 3G(miP6
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finalSerializable id){ l=v4Fa0^jF
return getHibernateTemplate().load PEc=\?
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(entity, id); R~S;sJ& c
} }n4V|f-
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publicObject get(finalClass entity, 9R7A8
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finalSerializable id){ U
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return getHibernateTemplate().get 5) pj]S!]-
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(entity, id); m>MB7,C;N
} i}B2R$Z3
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publicList findAll(finalClass entity){ ' <@3i[M
return getHibernateTemplate().find("from tF{D= ;G
p_${Nj
" + entity.getName()); ~wkj&yVT
} yrC7F`.
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publicList findByNamedQuery(finalString d~1gMz+)
cT!\{~
namedQuery){ Cd>WUw
return getHibernateTemplate
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MMx9(`t*.
().findByNamedQuery(namedQuery); VB,?Mo}R
} E: $P=%b
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publicList findByNamedQuery(finalString query, ^$'z!+QRM
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finalObject parameter){ f]\CD<g3|E
return getHibernateTemplate Na?!;1]_
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().findByNamedQuery(query, parameter); vJ-q*qM1
} [Z}9>~m
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publicList findByNamedQuery(finalString query, L_wk~z
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finalObject[] parameters){ ^]W<X"H+Z
return getHibernateTemplate L;'"A#Pa
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().findByNamedQuery(query, parameters); 3 G`aHTWk
} ?MgUY)X
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publicList find(finalString query){ Q=/</|
return getHibernateTemplate().find
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(query); }l],.J\BGX
} {:]9Q Tq
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publicList find(finalString query, finalObject dVi!Q@y+
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parameter){ p4-o/8rO
return getHibernateTemplate().find *U]V@;XF
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(query, parameter); (+FfB"3]
} t 0|!(3
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public PaginationSupport findPageByCriteria .tzG_
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(final DetachedCriteria detachedCriteria){ @]-jl}:]
return findPageByCriteria Qg[/%$x.
] 0B2#
d
(detachedCriteria, PaginationSupport.PAGESIZE, 0); pXtX jb
} i-6F:\;
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public PaginationSupport findPageByCriteria 8F&=a,ps[
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(final DetachedCriteria detachedCriteria, finalint aM:nOt" S1
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startIndex){ LkK~%tY
return findPageByCriteria W^]3XJP
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(detachedCriteria, PaginationSupport.PAGESIZE, kAC&S!n
k+8q{5>A<
startIndex); kMt 8/ E`
} }` ! =
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public PaginationSupport findPageByCriteria XAe%m^
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(final DetachedCriteria detachedCriteria, finalint Y~(Md@!0S
)_i
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pageSize, 371
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finalint startIndex){ \DD0s8
return(PaginationSupport) ,]cD
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getHibernateTemplate().execute(new HibernateCallback(){ [>1OJY.S}T
publicObject doInHibernate 70;Jl).\{
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(Session session)throws HibernateException { ,J{ei7TN
Criteria criteria = Bxfc}vC.
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detachedCriteria.getExecutableCriteria(session); ^,;z|f'%*
int totalCount = ,;Hu=;
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((Integer) criteria.setProjection(Projections.rowCount Y>E zTV
846$x$G4
()).uniqueResult()).intValue(); B{C??g8/
criteria.setProjection )Ib<F7v
TT4./R:
(null); WeQk<y
List items = Wr3mQU
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criteria.setFirstResult(startIndex).setMaxResults .Jrqm
0\@dYPa&C
(pageSize).list(); ~D5\O6mU-
PaginationSupport ps = o(r\E0I
l#H#+*F
new PaginationSupport(items, totalCount, pageSize, JoN\]JL\,
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startIndex); W'.s\e?gh
return ps; "E8zh|m o
} _&j}<K$-(
}, true); b r^_'1
} -Gw$#!
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public List findAllByCriteria(final u\LFlX0sO
MwR0@S}*
DetachedCriteria detachedCriteria){ j^;I3_P
return(List) getHibernateTemplate m"fNK$_d
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().execute(new HibernateCallback(){ spGB)k,^
publicObject doInHibernate ZP;j9T!
;3kj2}
(Session session)throws HibernateException { )~+ e`q
Criteria criteria = NDs!a
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detachedCriteria.getExecutableCriteria(session); VA9Gb9
return criteria.list(); 7G\\{
} L dm?JrU
}, true); {.De4]ANh
} |R56ho5C
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public int getCountByCriteria(final cFJ-Mkll
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DetachedCriteria detachedCriteria){ }yJ$SR]t
Integer count = (Integer) 3nu^l'WQ
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getHibernateTemplate().execute(new HibernateCallback(){ &3$z4df
publicObject doInHibernate _x?uU
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(Session session)throws HibernateException { qR8u$2}NY
Criteria criteria = /-qxS <?o
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detachedCriteria.getExecutableCriteria(session); ?@6/E<-Z$
return H.WE6
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criteria.setProjection(Projections.rowCount S3@|Q\*r
qKE:3g35
()).uniqueResult(); \igmv]G%
} .p=sBLp8
}, true); UH"#2< |b
return count.intValue(); l%`F&8K
} (&P9+Tl
} !Mu|mz=
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用户在web层构造查询条件detachedCriteria,和可选的 @0eHS+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0z[dlHi
2<][%> '
PaginationSupport的实例ps。 9XHz-+bQ
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ps.getItems()得到已分页好的结果集 a3VM'
ps.getIndexes()得到分页索引的数组 Z1h]
ps.getTotalCount()得到总结果数 sT/c_^y
ps.getStartIndex()当前分页索引 g1UGd
ps.getNextIndex()下一页索引 -PnyZ2'Z
ps.getPreviousIndex()上一页索引 ! {82D[5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 "iM~Hy
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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 M@(^AK{mU
QnI.zq
V
一下代码重构了。 Pa^A$fy\
k78Vh$AA6%
我把原本我的做法也提供出来供大家讨论吧: T?p`)
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首先,为了实现分页查询,我封装了一个Page类: Ln.ZVMZ;
java代码: Ox#Q2W@Uy
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/*Created on 2005-4-14*/ {&[9iIf
package org.flyware.util.page; E_1="&p
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{
/** aP&D9%5
* @author Joa o3Vn<Z$/Cl
* fRvAKz|rL
*/ ==H$zmK
publicclass Page { Vi]c%*k
7$k8%lI;>
/** imply if the page has previous page */ -.<k~71
privateboolean hasPrePage; D%7kBfCb
s-W[.r|
/** imply if the page has next page */ 46h@j>/K
privateboolean hasNextPage; )B!d,HKt;
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/** the number of every page */ w#
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privateint everyPage; 1P]de'-`j
r,N[ )@
/** the total page number */ t=R6mjb
privateint totalPage; l12$l<x&M
L fl-!1
/** the number of current page */ 7@PIM5h
privateint currentPage; Sg]
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/** the begin index of the records by the current \Xt)E[
q6wr=OWD
query */ N8!TZ~1$
privateint beginIndex; C2<CWPn<
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/** The default constructor */ i_F$&?)
public Page(){ }~o
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} (_9|w|(
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H`5
/** construct the page by everyPage q2_`v5t
* @param everyPage ~H[%vdR
* */ 4?/7
bc
public Page(int everyPage){ WA
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this.everyPage = everyPage; L8V3BH7B
} 1.R
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mjEs5XCC"
/** The whole constructor */ -{9Gagy2&
public Page(boolean hasPrePage, boolean hasNextPage, j[P8
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int everyPage, int totalPage, =J@`0H"
int currentPage, int beginIndex){ el'j&I
this.hasPrePage = hasPrePage; H/+{e,SW"
this.hasNextPage = hasNextPage; C=VIT*=
this.everyPage = everyPage; MB*u-N0v
this.totalPage = totalPage; w{'2q^>6*
this.currentPage = currentPage; 4&N$: j<
this.beginIndex = beginIndex; <{019Oa
} 2q%K)h
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/** `Lz1{#F2G
* @return O}gX{_|6
* Returns the beginIndex. yx0Q+Sm1:
*/ w3#`1T`N
publicint getBeginIndex(){ 7C5pAb:
return beginIndex; j??tmo
} pN$;!
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/** n(jjvLf
* @param beginIndex L#j|2H|
* The beginIndex to set. Lht[g9
*/ S\|^ULrH
publicvoid setBeginIndex(int beginIndex){ :^G%57NX
this.beginIndex = beginIndex; 0 [i+
} b5Q8pWZg,
l^,qO3ES
/** /p$=Cg[K
* @return
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* Returns the currentPage. n{=7 yK
*/ 6{7 3p@
publicint getCurrentPage(){ A7(M,4`6
return currentPage; NQ!<f\m4n
} p!GZCf,
M]B3vPA/v
/** M;qb7Mu
* @param currentPage !
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* The currentPage to set. 0l1.O2-
*/ O!];_q/
publicvoid setCurrentPage(int currentPage){ Bj&_IDs4
this.currentPage = currentPage; =43d%N
} N<"`ShCNM
K6(.KEW
/** \=8=wQv
* @return jIZ+d;1
* Returns the everyPage. F8 ?uQP8
*/ V{FE [v_
publicint getEveryPage(){ .ujj:>
return everyPage; /4H[4m]I
} Ivjw<XP6K
5&G
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/** vu ?3$
* @param everyPage X/wmKi
* The everyPage to set. &_YtY47
*/ yP%o0n/"x
publicvoid setEveryPage(int everyPage){ ;'hi9L
this.everyPage = everyPage; `11#J;[@G
} pEkOSG
0IpST
/** +Tp%5+E
* @return *0-v!\{
* Returns the hasNextPage. 'jN/~I
*/ vi<X3G6Xh
publicboolean getHasNextPage(){ 6I5o2i
return hasNextPage; r/^tzH's
} 1GUqT 9)
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/** %P(;8sS
* @param hasNextPage E;xMPK$
* The hasNextPage to set. &q"'_4
*/ }U(\~
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publicvoid setHasNextPage(boolean hasNextPage){ }}s8D>;G~
this.hasNextPage = hasNextPage; [pr 9 $Jr
} V8\$`NEP
rv`2*B
/** 8i[".9}G\
* @return )&XnM69~b
* Returns the hasPrePage. 8znj~7}#
*/ K q/~T7Ru
publicboolean getHasPrePage(){ #jhQBb4?,
return hasPrePage; jT{f<P0
} 8g.AT@ ,Q
{ip=iiW2
/** kSB3KR;~n
* @param hasPrePage 692Rw}/
* The hasPrePage to set. fVG$8tB
*/ &K+
publicvoid setHasPrePage(boolean hasPrePage){ uXjoGcW
this.hasPrePage = hasPrePage; yLjV[qP
} tF<^9stM
\>4v?\8o
/** Z+r%_|kZ
* @return Returns the totalPage. j p!
* V+peO
*/ YW'{|9KnI
publicint getTotalPage(){ 5?Uo&e
return totalPage; ||yXp2
} 3%_
4+zd
Hde]DK,d
/** W+8BQ-2
* @param totalPage ,2RC |h^O,
* The totalPage to set. *^X#Eb
*/ SAd97A:
publicvoid setTotalPage(int totalPage){ Jq=00fcT+
this.totalPage = totalPage; fEHh]%GT`
} m$7x#8gF
j|&{e91,?
} 6e-#XCR{
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|P^]@om
7vii9Am7
cSY2#u|v
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 -
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->#y(}
个PageUtil,负责对Page对象进行构造: )`B
-O::
java代码: CWE Ejl
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p
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/*Created on 2005-4-14*/ Ix*BI9E
package org.flyware.util.page; .tZjdNE(h
8W19#?7>B
import org.apache.commons.logging.Log; 4$0jz'
import org.apache.commons.logging.LogFactory; N90\]dFmy
?l6>6a7
/** 5u'TmLuKT
* @author Joa Q
mb[ e>
* c+@d'yR
*/ lAdOC5+JX
publicclass PageUtil { l84h%,
*Te4U5F
privatestaticfinal Log logger = LogFactory.getLog ?R|fS*e2EB
Z_iAn TT
(PageUtil.class); 4?9soc
xaGVu0q
/** j#*asGdp#J
* Use the origin page to create a new page 9F2w.(m
* @param page pieU|?fQ
* @param totalRecords :)KTZ
* @return Fy}MXe"f
*/ 7sQ]w
publicstatic Page createPage(Page page, int uB5h9&57
'_q: vjX
totalRecords){ o7_MMeQ4
return createPage(page.getEveryPage(), lH#@^i|G
xFsB?d
page.getCurrentPage(), totalRecords); !A'`uf4u
} |1dEs,z\
ka?IX9t\
/** pm'@2dT
* the basic page utils not including exception Bq$e|t)'
E3CiZ4=5
handler Gt\K Ln
* @param everyPage bR>o!(M'Z\
* @param currentPage 9B!im\]O
* @param totalRecords 3bg4# c
* @return page ,xtKPA
*/ b'Fx),
publicstatic Page createPage(int everyPage, int >gX0Ij#G
RE`J"&
currentPage, int totalRecords){ 877EKvsiC
everyPage = getEveryPage(everyPage); >D`fp
currentPage = getCurrentPage(currentPage); 0j
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int beginIndex = getBeginIndex(everyPage, Se^/VVm
jm#d7@~4
currentPage); t_dw}I
int totalPage = getTotalPage(everyPage, s0XRL1kWr
Vq .!(x
totalRecords); 1c<CEq:?e%
boolean hasNextPage = hasNextPage(currentPage, p0[,$$pM
"W_jdE6v
totalPage); gCk y(4
boolean hasPrePage = hasPrePage(currentPage); L#7)X5a__
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returnnew Page(hasPrePage, hasNextPage, Uf7F8JZmM
everyPage, totalPage, I |<+'G
currentPage, 6yu*a_
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@@
beginIndex); e~t}z_>F
} X5L(_0?F1
(2O} B.6
privatestaticint getEveryPage(int everyPage){ 6uCk0
B|
return everyPage == 0 ? 10 : everyPage; r7Q:l ?F2
} Z5*(W;;
aCUV[CPw
privatestaticint getCurrentPage(int currentPage){ T4H oSei
return currentPage == 0 ? 1 : currentPage; A5.'h<
} ld!6|~0U
^EuyvftZ
privatestaticint getBeginIndex(int everyPage, int ArmL,
(v'lb!j^#
currentPage){ 8JtI&aH-L
return(currentPage - 1) * everyPage; nIT ^'
} ziLr }/tg
CQ8o9A/
privatestaticint getTotalPage(int everyPage, int 1VjeP
*
A=qW]Im
totalRecords){ U3_yEvZ
int totalPage = 0; ?) ,xZ1"
y1\^v_.^
if(totalRecords % everyPage == 0) t0asW5f
totalPage = totalRecords / everyPage; (!>g8=`"
else [#Nx>RY
totalPage = totalRecords / everyPage + 1 ; Xg!|F[i
#nc@!+
return totalPage; 5cNzG4z
} e@2Vn? 5
.z-^Ga*
privatestaticboolean hasPrePage(int currentPage){ YAC zznN
return currentPage == 1 ? false : true; X,!OWz:[
} |Z7bd^
Q5Ghki
privatestaticboolean hasNextPage(int currentPage, DO- K
<k-@R!K~JC
int totalPage){ /<?X-IDz.{
return currentPage == totalPage || totalPage == MY<!\4/
?;KJ
(@Va
0 ? false : true; Etr8lm E
} h&k^l,
#`#aSqGmc
]g-qWSKU
} -< dMD_
n"d)
L%s4snE
!
^*;c#
#L4Kwy
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。 !,JT91
k89gJ5B$
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 agxSb^ 8tF
KlqJEtO_
做法如下: /qhm9~4e3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 I`$I0
*~<]|H5~
的信息,和一个结果集List: |3T|F3uEX
java代码: uuK]<h*
AGJ=de.
Oi%~8J>
/*Created on 2005-6-13*/ (zYSSf!I
package com.adt.bo; ie)1 h
R
EH&kcn
import java.util.List; Jgv>$u
bb:|1D
import org.flyware.util.page.Page; gZ >orZL'
#z^1)7
/** =#")G1A
* @author Joa FZ.z'3I
*/ ,N|R/Vk$+E
publicclass Result { RdVis|7o
f!8m
private Page page; E29gnYxu8
@?cXa: tX
private List content; H6CGc0NS+
?O>JtEz~lQ
/** $No>-^)
* The default constructor dVtLYx
*/ f{5|}PL
public Result(){ K2o0L5Lke
super(); ihY^~
} d8
Nh0!
I
3,e)Z
/** 6V6g{6W,/
* The constructor using fields rbZ6V :
* }xlmsOHuI
* @param page nC{rs+P
* @param content M "P
*/ RTA=|q
public Result(Page page, List content){ l3#dfW{
this.page = page; Fl3r!a!P,
this.content = content; '\E{qlI
} }'0Xz9/ l
glX2L~
/** YeVc,B'
* @return Returns the content. N\e@$1
*/ k3.p@8@:
publicList getContent(){ Qbpl$L
return content; ~dr1Qi#j?
} p#BvlS=D
;Hp' x_xQ
/** w:xKgng=L
* @return Returns the page. Y@S6m@.$
*/ v]SE?xF{U
public Page getPage(){ >MY.Fr#.m
return page; Cj9O[
} 'wnY>hN
Jl4XE%0
/** ftuQ"Ds
* @param content CF92AY
* The content to set. UKQ&TV}0
*/ v4~Xv5|w^F
public void setContent(List content){ 0F'UFn>{
this.content = content; >$52B9ie
} m$qC
8z]
NG!Q< !Y
/** Ck%(G22-
* @param page W&f Py%g
* The page to set. .p~;U|h"
*/ #LgoKiP!Y
publicvoid setPage(Page page){ :!!`!*!JH
this.page = page; N;pr:
} #R4KBXN
} &U)s%D8e;d
c7!`d.{90
G6VHl:e7z
IqKXFORiNI
A"VXs1>_^
2. 编写业务逻辑接口,并实现它(UserManager, L([ >yQZ
''Ec-b6Q-
UserManagerImpl) )'|W[Sh?
java代码: EZRZ)h
1)Bi>X
^WPV
/*Created on 2005-7-15*/ iPpJ`i#@+
package com.adt.service; H,` XCG
<yO9j
import net.sf.hibernate.HibernateException; wh+ibH}@!
"0)G|pZI
import org.flyware.util.page.Page; JjML!;
ZM`_P!G
import com.adt.bo.Result; c&(,
mLA$F4/K
/** nDw9
* @author Joa 1V?)zp
*/ $Ws2g*i
publicinterface UserManager { +@7R,8
RE$-{i
public Result listUser(Page page)throws U5
"v1"Ec
.6#2i <oPW
HibernateException; p:%E>K1<
2F7R,rr
} x^BBK'
"ZW*O{
3l[hkRFu`
J<@]7)|U
hJNA%
java代码: 5L#M7E
r :-WfDz.
8;3FTF
/*Created on 2005-7-15*/ pl&GFf
o
package com.adt.service.impl; Fj4:_(%nG
!!%F$qUd\
import java.util.List; ABGL9;.8
oGJI3Oh
import net.sf.hibernate.HibernateException; A???s,F_
z[OEgHI
import org.flyware.util.page.Page; W>Kn*Dy8~
import org.flyware.util.page.PageUtil; %SXqJW^:
~<LI p%5(
import com.adt.bo.Result; 0IuU4h5Fr
import com.adt.dao.UserDAO; N@S;{uK
import com.adt.exception.ObjectNotFoundException; k2;yl_7
import com.adt.service.UserManager; u}_q'=<\
_`58G#z
/** '#?hm-Ga
* @author Joa q 9^r2OO
*/ )DMbO"7
publicclass UserManagerImpl implements UserManager { 0c)19Ig
up6LO7drW/
private UserDAO userDAO; .&xc2sRZ
;$]R#1i44
/** UQy+&;#5
* @param userDAO The userDAO to set. u#QQCgrs
*/ S7R^%Wck/6
publicvoid setUserDAO(UserDAO userDAO){
8~7EWl
this.userDAO = userDAO; +H_Z!T.@
} 4" @yGXUb
y|ZJ-[qg
/* (non-Javadoc) WD]dt!V%
* @see com.adt.service.UserManager#listUser klKt^h-
p/:L;5F
(org.flyware.util.page.Page) (RF6K6~
*/ 0@KBQv"v
public Result listUser(Page page)throws hLF@'ln
X|as1Y$O+
HibernateException, ObjectNotFoundException { O<5bsKw'r
int totalRecords = userDAO.getUserCount(); P`0aU3pl
if(totalRecords == 0) <W1!n$V ]
throw new ObjectNotFoundException aOOY_S
E
LQ._?35r
("userNotExist"); e_e|t>nQ
page = PageUtil.createPage(page, totalRecords); KW)yTE<
List users = userDAO.getUserByPage(page); #t\Oq9}^
returnnew Result(page, users); 4V=dD<3m
} ,}<v:!
lVtgg?
} _\"?:~rUN
$W)FpN;CW/
r\yj$Gu>(
\J6T:jeS,
V%+KJ}S!Z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 i/->g:47P
G[jCmkK
询,接下来编写UserDAO的代码: yRAb
HG,c
3. UserDAO 和 UserDAOImpl: ~k&b3-A}
java代码: ,]+6kf 5
Z#0z #M`
St?vd+(>
/*Created on 2005-7-15*/ -y~JNDS1]
package com.adt.dao; ks!
G \<I
V'_^g7}l&
import java.util.List; PR Y)hb;1
]wP)!UZ
import org.flyware.util.page.Page; K[sfsWQ.
^LZU><{';
import net.sf.hibernate.HibernateException; _M7AQ5
pNDL:vMWP
/** )y8$-"D(it
* @author Joa #<)u%)`
*/ o rEo$e<
publicinterface UserDAO extends BaseDAO { >%xJ e'
G.9?ApG9
publicList getUserByName(String name)throws H4)){\
nU/v(lN
HibernateException; )@Ly{cw
xl
s_g/Q
publicint getUserCount()throws HibernateException; 8c#u"qF
b"p,~{
publicList getUserByPage(Page page)throws zK33.HY
T*z >A
HibernateException; '9-8_;
^oj)#(3C
} m"`&FA
^;N+"oq!y
>0{{loqq
R}BHRmSQ
Ig]Gg/1G
java代码: +oeO0
Hw_(Af?C
8LB+}N(8f
/*Created on 2005-7-15*/ z>hA1*Ti
package com.adt.dao.impl; ?%F*{3IP
&p0*:(j
import java.util.List; GYZzWN}U
!|hv49!H
import org.flyware.util.page.Page; Td}#o!4!
J6Cw1Pi
import net.sf.hibernate.HibernateException; Ydh]EO0'
import net.sf.hibernate.Query; -Y{P"!p0
h]&8hl_'m
import com.adt.dao.UserDAO; 6;k#|-GU&
l}># p'$
/** \5cAOBja
* @author Joa t=Tu-2,k
*/ =.f]OWehu.
public class UserDAOImpl extends BaseDAOHibernateImpl ul1#_xp
\|R P-8
implements UserDAO { Ns?y)
G>:
Pl9/1YhD/
/* (non-Javadoc) 1^TOTY
* @see com.adt.dao.UserDAO#getUserByName ojni+} >_
$d'GCzYvZ
(java.lang.String) lZ'-?xo
*/ F_$eu-y
publicList getUserByName(String name)throws fE8/tx](
x!"S`AM
HibernateException { l
2y_Nz-;
String querySentence = "FROM user in class 17
Hdj
615, P/
com.adt.po.User WHERE user.name=:name"; J*IC&jH:
Query query = getSession().createQuery be}^}w=
hlWTsi4N
(querySentence); `D6Bw=7
query.setParameter("name", name); L&H4fy!>
return query.list(); #XE`8$
} iqW
T<WY
epqX2`!V
/* (non-Javadoc) v,#*%Gn`%
* @see com.adt.dao.UserDAO#getUserCount() 21_>|EKp
*/ %}t.+z(S
publicint getUserCount()throws HibernateException { J39,x=8LL
int count = 0; t:X\`.W
String querySentence = "SELECT count(*) FROM Q&S\?cKe
PBc.}TSGj
user in class com.adt.po.User"; &_n~# Mex
Query query = getSession().createQuery ,{!~rSq-l
_1S^A0ft
(querySentence); $$_aHkI j
count = ((Integer)query.iterate().next F$T@OT6
$\h\,N$y
()).intValue(); {PZNJ 2~
return count; dP}=cZ~
}
*(5y;1KU
%9B r
/* (non-Javadoc) /2Q@M>
* @see com.adt.dao.UserDAO#getUserByPage ]"Z*Hq
z
JFf*v6:,
(org.flyware.util.page.Page) ASME~]]?
*/ :I*G tq
publicList getUserByPage(Page page)throws kW=g:m
mv_N ns
HibernateException { uSh!A
String querySentence = "FROM user in class hqOy*!8'@
frV* +
com.adt.po.User"; Wm! lWQu7
Query query = getSession().createQuery S3EM6 `q'
~$xLR/{y
(querySentence); |eH>55 b
query.setFirstResult(page.getBeginIndex()) M5DQ{d<r
.setMaxResults(page.getEveryPage()); ODa+s>a`^
return query.list(); )pELCk
} aD)XxXwozm
k=">2!O/
} CGmObN8~'F
r,F~Vwa}
5MUM{(C
pd2Lc
$O@
"f/91gIzm'
至此,一个完整的分页程序完成。前台的只需要调用 =[{YI2S
v[4A_WjT
userManager.listUser(page)即可得到一个Page对象和结果集对象 .u[hK
Z+%Uwj
的综合体,而传入的参数page对象则可以由前台传入,如果用 TTB1}j+V6
N0APX4j
webwork,甚至可以直接在配置文件中指定。 ukM11LD5x
7g@P$e]
下面给出一个webwork调用示例: W[B%,Km%]
java代码: bMWL^ *I
i"|="O0v5
kT|{5Kn&s
/*Created on 2005-6-17*/ %tx~CD
package com.adt.action.user; $x_6
.AOZ,
v,6
import java.util.List; 9nW/pv
xRum q
import org.apache.commons.logging.Log; XP#j9CF#.
import org.apache.commons.logging.LogFactory; `>M;f%s
import org.flyware.util.page.Page; rHhn)m
} Ej^M~Vv
import com.adt.bo.Result; r0
%WGMk2
import com.adt.service.UserService; y k=o
import com.opensymphony.xwork.Action; r8PXdNg
wk
@-O}W
/** `LD#fg*
* @author Joa B_;W!
*/ j#KL"B_A
publicclass ListUser implementsAction{ +<cvyg5U
yO@KjCv"
privatestaticfinal Log logger = LogFactory.getLog j9)WInYc:
9OIX5$,S;
(ListUser.class); ;^QG>OP$
3&*_5<t\X
private UserService userService; HK~uu5j
?$rSbw
private Page page; KIt:ytFx
h@nNm30i
privateList users; S@Rw+#QE
8<cD+Jtj
/* uc6;%=%+
* (non-Javadoc) AiUICf?{
* UclQo~3
* @see com.opensymphony.xwork.Action#execute() }(}+I}&~
*/ 8;'fWV?
U
publicString execute()throwsException{ uXx c2}
Result result = userService.listUser(page); ,,*i!%Adw
page = result.getPage(); "wk~[>
users = result.getContent(); ]<3$Sx_{y
return SUCCESS; 7"L`|O?8)
} ["'0vQ
PFP/Pe Ng;
/** RS`]>K3t
* @return Returns the page. aBV{Xr~#(
*/ CuE>=y-"I
public Page getPage(){ l.tNq$3pS
return page; {?-@`FR-
} D@[Mk"f
C^uH]WO
/** W/dl`UDY
* @return Returns the users. }m6zu'CV
*/ zB 6u%u WR
publicList getUsers(){ -Fcg}\9
return users; +8+@Az[e0
} 'jv[Gcss3L
YyR)2j1O
/** MPt:bf#
* @param page RfP>V/jy5
* The page to set.
x Bn+-V
*/ ,X Zo0!
publicvoid setPage(Page page){ u!in>]^
this.page = page; %vPs38Fks
} P19nF[A
yRQR@
/** aL\vQ(1zO
* @param users V=";vRS8
* The users to set. ["|' f
*/ #V4kT*2P)
publicvoid setUsers(List users){ K\5'pp1
this.users = users; lSw9e<jYO
} pDr%uL
_is<.&f6
/** nZ?BCO
* @param userService ^4@~\#$z
* The userService to set. >*ey 7g
*/ "bFt+N
publicvoid setUserService(UserService userService){ 5m,{?M`
this.userService = userService; ?haN ;n6'
} bH}6N>Fp
} -^=sxi,V
!a&@y#x
~.qzQ_O/
Q9X7-\n
$x&@!/&|pv
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, I(fq4$
g0 ec-
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 J{$+\
[u[`!L=
么只需要: 6
W/S?F~{
java代码: @vWC "W
%)[m bb
olPV"<;+pO
<?xml version="1.0"?> r(` ;CY]@
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ,<$6-3sC-
l,Un7]*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- '0g1v7Gx
qJ QE|VM&
1.0.dtd"> D$g|f[l
Ojj:YLlY>
<xwork> z)Xf6&
O@[c*3]e
<package name="user" extends="webwork- $3BCA)5:
d=%:rLm$
interceptors"> }IvJIr
j:D@X=|
<!-- The default interceptor stack name LO@.aJpp
0T 2h3,
--> I}/o`oc
<default-interceptor-ref G)\s{qk
8cn)ox|J[
name="myDefaultWebStack"/> `j*&F8}
)c=R)=N
<action name="listUser" 87%t=X
6GCwc1g
class="com.adt.action.user.ListUser"> F/9]{H
<param .#R\t 7m%
a,o)i8G9R<
name="page.everyPage">10</param> 5VIpA
<result 2UY0:ye
PT4Xr=z =
name="success">/user/user_list.jsp</result> MfUG@
</action> q[{q3-W
nt\6o?W
</package> FRI<A8
*leQd^47
</xwork> ]xQPSs_
"!<Kmh5
vPEL'mw/3#
P0U=lj/b
KquHc-fzqr
DG8]FhD^b
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 ,p\^n`A32
iRo UM.%
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。 F7J-@T<
8'J>@ uW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^_3idLE
B9|!8V
z<c^<hE:l
[P)'LY6F
e:{v.C0ez
我写的一个用于分页的类,用了泛型了,hoho XG
]yfux`
x{<WJ|'B
java代码: 2D`@$)KL
e8gJ }8Fj
YIb5jK`
package com.intokr.util; @uz&]~+`
T8>:@EL-k
import java.util.List; &H,5f#
QU16X
/** )hK5_]"lmj
* 用于分页的类<br> t3u"2B7oG
* 可以用于传递查询的结果也可以用于传送查询的参数<br> wxpD{P
* ~R-S$qizAC
* @version 0.01 (:2:_FL
* @author cheng EU]{S=T
*/ *MW)APw=
public class Paginator<E> { >x@]wsj
privateint count = 0; // 总记录数 Xtbuy/8"1
privateint p = 1; // 页编号 1i#uKKwE
privateint num = 20; // 每页的记录数 hXM8`iFW5
privateList<E> results = null; // 结果 eS fT+UL
s4P8PDhz
/** E4[
|=<
* 结果总数 _CAWD;P
*/ f!ehq\K1k
publicint getCount(){ xy46].x-
return count; ?XL [[vyr
} pl
Ii
<<@\K,=
publicvoid setCount(int count){ 5tHv'@
this.count = count; pSkP8'
?
} 85$MHod}[,
\c/jp5=}
/** i0 {pm q
* 本结果所在的页码,从1开始 \$^ z.
* u /JEQz1
* @return Returns the pageNo. m'Z233Nt"
*/ c.6u)"@$
publicint getP(){ w7p%6m
return p; 6:>4}WOP
} B<DvH"+$
>`n0{:.1za
/** ~cy/\/oO
* if(p<=0) p=1 'IP'g,o++
* ].]yqD4P
* @param p 'e02rqip{
*/ 0z&3jWWY@
publicvoid setP(int p){ (FbqKx'uq
if(p <= 0) :-.R*W
p = 1; S0/@y'q3en
this.p = p; wX8T;bo&
} f"xi7vJv!f
:y !e6
/** DF%\1C>
* 每页记录数量 !jMa%;/
*/ h|yv*1/|
publicint getNum(){ \E9Z
H3;
return num; =#^%; 6 6z
} mj[PKEdkB
~-GgVi*I
/** T=:O(R1*0
* if(num<1) num=1 V;L^q?v
!
*/ yJWgz`/L
publicvoid setNum(int num){ "^ydoRZ
if(num < 1) (
Z\OqG
num = 1; 24Z7;'
this.num = num; SWUHHl
} 'I($IM
A`Z!=og=
/** i]Lt8DiRq
* 获得总页数 zAC
*/ l^:m!SA_
publicint getPageNum(){ b(_PCVC
return(count - 1) / num + 1; TOn{o}Y B
} _2q4Aaza
S9<J\`FG
/** lu`\6
* 获得本页的开始编号,为 (p-1)*num+1 Ym(^ih
*/ $@FD01h.t3
publicint getStart(){ L^KGY<hp4
return(p - 1) * num + 1; chQt8Ar3
} @SDsd^N{2P
p H5IBIf'
/** zPe4WE|
* @return Returns the results. BXO(B'1)]
*/ jx!)N>
publicList<E> getResults(){ }$hxD9z
return results; k[6@\D-
} @%IZKYfc~
@4B+<,i
public void setResults(List<E> results){ Z=sy~6m+v
this.results = results; pL]C]HGv
} ?t'ZX~k
FviLlly6
public String toString(){ S]KcAz( fX
StringBuilder buff = new StringBuilder T [N:X0
gAhCNOp
(); =%znY`0b56
buff.append("{"); E8T4Nh_
buff.append("count:").append(count);
$Tfq9
buff.append(",p:").append(p); [z]@<99/
buff.append(",nump:").append(num); K7FuMB
buff.append(",results:").append Nv,[E+a2
5~<>h~yJ
(results); W,`u5gbT
buff.append("}"); ')5W
return buff.toString(); {:IOTy
} ,ZJI]Q=!
82&JYx
} zid?yuP
qBpv[m
9xB^dKM3