Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #+H3b!8=
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^HU>fkSk
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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 W=y9mW|p/
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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 !yvw5As %
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分页支持类: /IlO
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java代码: -Un"z6*
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package com.javaeye.common.util; 8_Z"@
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import java.util.List; i|0!yID0@
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publicclass PaginationSupport { b'I@TLE')
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publicfinalstaticint PAGESIZE = 30; 9rIv-&7'm
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privateint pageSize = PAGESIZE; _88X-~.
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privateList items; 8?rq{&$t
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privateint totalCount; l3+G ]C&<
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privateint[] indexes = newint[0]; b81cq,
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privateint startIndex = 0; ~i.rk#{?D
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public PaginationSupport(List items, int 0d$LUQ't
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totalCount){ nkz<t
setPageSize(PAGESIZE); 1d$wP$
setTotalCount(totalCount); GP x+]Jw8\
setItems(items); FxT]*mo
setStartIndex(0); &XW~l>!+
} TxH
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public PaginationSupport(List items, int 3NdO3-~)
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totalCount, int startIndex){ wv=U[:Y
setPageSize(PAGESIZE); .J=QWfqt
setTotalCount(totalCount); F0"("4h:
setItems(items); DHbS=Iih
setStartIndex(startIndex); c[;A$P=
8.
} 3#aLCpVla
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public PaginationSupport(List items, int 4hYK$!"r
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); C>F5=&
setTotalCount(totalCount); ~jzT;9:
setItems(items); _n4_;0
setStartIndex(startIndex); ;kZJnN"y
} =$ T[
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publicList getItems(){ 06`caG|]-M
return items; EpTc{
} 9!0-~,o
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publicvoid setItems(List items){ xgtx5tg
this.items = items; 69t6lB#;!
} AG#Mj(az!
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publicint getPageSize(){ ma/<#l^}
return pageSize; >.H}(!
} C0khG9,BL
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publicvoid setPageSize(int pageSize){ |oQhtk8.
this.pageSize = pageSize; 9JeT1\VvHY
} R*lq.7
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publicint getTotalCount(){ dp2FC
return totalCount; I]cZcx,<q
} MlLM
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gt=@v())
publicvoid setTotalCount(int totalCount){ #KuBEHr
if(totalCount > 0){ #iRd2Qj%
this.totalCount = totalCount; _bv9/# tR
int count = totalCount / #MviO!@
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T
pageSize; 0IHAoV60
if(totalCount % pageSize > 0) {$7vd
count++; vrh2}biCR
indexes = newint[count];
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for(int i = 0; i < count; i++){ |Qpd<L
indexes = pageSize * Gs4t6+Al
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} .eCUvX`$
}else{ D+w?
this.totalCount = 0; @Y ?p-&
} qZlL6
} q9\(<<f|
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publicint[] getIndexes(){ +S1h~@c:B
return indexes; 76u\#{5
} H1
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publicvoid setIndexes(int[] indexes){ w;kiH+&
this.indexes = indexes; hn$jI5*`
} E};1
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publicint getStartIndex(){ ;0Ih:YY6
return startIndex; 0OnqKgf
} A>)W6|m|
bkm:#K
publicvoid setStartIndex(int startIndex){ (m')dSZ
if(totalCount <= 0) R0nUS<b0
this.startIndex = 0; 3=0b
elseif(startIndex >= totalCount) ,fhwDqR
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this.startIndex = indexes y+7A?"s)
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[indexes.length - 1]; ;9)=~)
elseif(startIndex < 0) " "CNw-^t
this.startIndex = 0; >^v,,R8j
else{ T+:GYab/
this.startIndex = indexes jz I,B
("=B,%F_
[startIndex / pageSize]; 0{stIgB$
} ?zYR;r2'b)
} #BI6+rfv|
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publicint getNextIndex(){ +@do<2l]
int nextIndex = getStartIndex() + BbgKaC q
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pageSize; '=UsN_@
if(nextIndex >= totalCount) b^<7@tY
return getStartIndex(); l i%8X.
else )r
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return nextIndex; h3p~\%^
} yq` ,)
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publicint getPreviousIndex(){ 't475?bY
int previousIndex = getStartIndex() - ?u{D-by%&
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pageSize; raZ0B,;eFu
if(previousIndex < 0) &Z+.FTo
return0; 8]J lYe
else $-n_$jLY
return previousIndex; J^mm"2
} gv,%5r0YOw
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} fBPJ8VY
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抽象业务类 ^!K 8nW{*
java代码: &G7@lz@sK+
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/** 0"u=g)3
* Created on 2005-7-12 U> {CG+X
*/ ZRC7j?ui8`
package com.javaeye.common.business; XK
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import java.io.Serializable; A~'p~@L
import java.util.List; 0Pg@%>yb~
,.,Y{CP
import org.hibernate.Criteria; wKy4Ic+RV
import org.hibernate.HibernateException; \6,Z<.I
import org.hibernate.Session; w6'8L s
import org.hibernate.criterion.DetachedCriteria; kk/vgte-)e
import org.hibernate.criterion.Projections; BWsD~Ft
import |bjLmGb
'h{DjNSM
org.springframework.orm.hibernate3.HibernateCallback; #M8>)o c
import Y1 6pT
cP8@'l@!
org.springframework.orm.hibernate3.support.HibernateDaoS /S%!{;:
2$oGy
upport; tOw[
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import com.javaeye.common.util.PaginationSupport; 20mZ{_%
Q37zBC0
public abstract class AbstractManager extends w7_2JS
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HibernateDaoSupport { @#| R{5=+
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privateboolean cacheQueries = false;
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privateString queryCacheRegion; JT 5+d ,
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publicvoid setCacheQueries(boolean O}"fhMk
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cacheQueries){ AmT*{Fz8
this.cacheQueries = cacheQueries; ktK/s!bgY
} 1z=}`,?>
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publicvoid setQueryCacheRegion(String M.}QXta
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queryCacheRegion){ 7)au#K6
this.queryCacheRegion = .t9zF-jk
}@wXm
queryCacheRegion; [{9&KjI0K
} lpeo^Y}N
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publicvoid save(finalObject entity){ .Dg'MMBM
getHibernateTemplate().save(entity); T 9?!.o
} *gXm&/2*
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publicvoid persist(finalObject entity){ &0S/]E`_M
getHibernateTemplate().save(entity); @?"t&h
} 1Du9N[2'P
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publicvoid update(finalObject entity){ L\UM12
getHibernateTemplate().update(entity); Fgg4QF
} 5Ai$1'*p
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publicvoid delete(finalObject entity){ )d-{#
getHibernateTemplate().delete(entity); f^X\ N/
} .:#6dG\0z
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publicObject load(finalClass entity, [u2)kH$
},LW@Z}
finalSerializable id){ 7 }sj&
return getHibernateTemplate().load QabYkL5@
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(entity, id); &g<`i{_
} `+0)dTA(g$
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publicObject get(finalClass entity, :WBl0`kW]4
k)R>5?_
finalSerializable id){ VG`A* Vj
return getHibernateTemplate().get ; i><03
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(entity, id); ba
} >, }m=X8
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publicList findAll(finalClass entity){ [0G>=h@u
return getHibernateTemplate().find("from kY6))9 O
d.&~n`Rv!p
" + entity.getName()); D0&{iZ(
} LvNk:99:<
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publicList findByNamedQuery(finalString $0zH2W
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namedQuery){ Up$vBE8i]
return getHibernateTemplate f V.(v&
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().findByNamedQuery(namedQuery); 1dK^[;v>3
} ^OQ#N z
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publicList findByNamedQuery(finalString query, R%Yws2Le2
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finalObject parameter){ '4A8\&lQO
return getHibernateTemplate r(yb%p+
&7X0 ;<
().findByNamedQuery(query, parameter); -~h2^Oez
} 1q!6Sny@
[J+K4o8L<A
publicList findByNamedQuery(finalString query, 4>^ %_Xj[
@]HV:7<q
finalObject[] parameters){ ";e0-t6:
return getHibernateTemplate viBf".
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().findByNamedQuery(query, parameters); b`K~l'8
} 8L 9;VY^Y
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publicList find(finalString query){ p$@=N6)I.k
return getHibernateTemplate().find <96ih$5D1
q#PGcCtu
(query); y\@;s?QL
} zq]V6.]J
=k`(!r2"#
publicList find(finalString query, finalObject bah5 f
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parameter){ ~eL7=G@{
return getHibernateTemplate().find &^9>h/-XT
s$:]$&5
(query, parameter); Zk}e?Grc
} ( L RX
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public PaginationSupport findPageByCriteria a+mq=K
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(final DetachedCriteria detachedCriteria){ ^ I,1kl~i
return findPageByCriteria
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7!JoP?!
(detachedCriteria, PaginationSupport.PAGESIZE, 0); :N)7SYQT
} 3g2t{%
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public PaginationSupport findPageByCriteria K{>O.5
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(final DetachedCriteria detachedCriteria, finalint hY'"^?OP
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startIndex){ iJrscy-
return findPageByCriteria on&N=TN
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(detachedCriteria, PaginationSupport.PAGESIZE, ^#^u90I
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startIndex); =AcbX_[
} ;co{bk|rj
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public PaginationSupport findPageByCriteria ]P<&CEk
"v*RY "5#
(final DetachedCriteria detachedCriteria, finalint \wDOE(>
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pageSize, oS,<2Z
finalint startIndex){ [sNn^x
return(PaginationSupport) sCRBKCR?
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getHibernateTemplate().execute(new HibernateCallback(){ Y@.JW
publicObject doInHibernate W+K=M*^D;c
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(Session session)throws HibernateException { @fE^w^K7
Criteria criteria = 6gR=e+
bh7 1Zu
detachedCriteria.getExecutableCriteria(session); ^*{xTB57
int totalCount = U5H o? `<
o!\O)
((Integer) criteria.setProjection(Projections.rowCount E!Fy2h>[Z
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()).uniqueResult()).intValue(); %] #;
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criteria.setProjection Cq(Xa-
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(null); G0]n4"~+?
List items = +.lO8
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criteria.setFirstResult(startIndex).setMaxResults -O_UpjR;
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(pageSize).list(); |[{;*wtv
PaginationSupport ps = ;D^)^~7dh
l
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new PaginationSupport(items, totalCount, pageSize, 3mm`8!R
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startIndex); <hK$Cf_
return ps; q90S>c,
} TM^1{0;r5
}, true); n~)Y% xe[U
} )$]+R?v
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public List findAllByCriteria(final U/iAP W4U
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DetachedCriteria detachedCriteria){ M5x!84
return(List) getHibernateTemplate ?D\%ZXo
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().execute(new HibernateCallback(){ 3,F/i+@
publicObject doInHibernate {!/y@/NK2
O\D({>
(Session session)throws HibernateException { [y{ag{
Criteria criteria = C`jP8"-
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detachedCriteria.getExecutableCriteria(session); c'|MC[^A
return criteria.list(); 9e1 6 g
} xLD6A5n,[
}, true); v :HgpZo+
} `Eu(r]:W
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public int getCountByCriteria(final P5d@-l%}
{&<}*4D
DetachedCriteria detachedCriteria){ ,m"ztu-
Integer count = (Integer) @LE?XlhD
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getHibernateTemplate().execute(new HibernateCallback(){ r2](~&i2
publicObject doInHibernate jo |q,t
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(Session session)throws HibernateException { NSgHO`gU8
Criteria criteria = )4`Ml*7x
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detachedCriteria.getExecutableCriteria(session); /-hF<oNQ
return Xou#38&p>
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criteria.setProjection(Projections.rowCount nfJ8Rt
#PrV)en
()).uniqueResult(); j^ _I{
} a?Y1G3U'
}, true); d=#p w*w
return count.intValue(); ?V{k\1A
} x<Zhj3
} B![5+
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用户在web层构造查询条件detachedCriteria,和可选的 >Y/[zfI2
bg ,}J/
startIndex,调用业务bean的相应findByCriteria方法,返回一个 46zaxcY<!
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PaginationSupport的实例ps。 FR}H$R7#
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ps.getItems()得到已分页好的结果集 Ke ?uE
ps.getIndexes()得到分页索引的数组 ^c\ IZ5
ps.getTotalCount()得到总结果数 ya{>=
ps.getStartIndex()当前分页索引 }K>HS\e
ps.getNextIndex()下一页索引 @:7gHRJ!
ps.getPreviousIndex()上一页索引 B
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 lk +K+Ra/
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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 &'7"i~pC
}iSakq'
一下代码重构了。 g&4~nEp
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我把原本我的做法也提供出来供大家讨论吧: {F:v$ K
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首先,为了实现分页查询,我封装了一个Page类: 5FSv"=
java代码: B/=q_.1F>
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/*Created on 2005-4-14*/ q.MVF]
package org.flyware.util.page; AD@PNM
=YGP%}_.p{
/** }IN_5o((
* @author Joa (b%y$D
* jBv$^L
*/ *>'2$me=
publicclass Page { *kQCW#y0
atf%7}2
/** imply if the page has previous page */ ay(!H~q_U
privateboolean hasPrePage; $W$# CTM
!&`\ LJ=j
/** imply if the page has next page */ D4q>R;
privateboolean hasNextPage; (s"iC:D6U
@%<?GNS O
/** the number of every page */ u5Ny=Xm
privateint everyPage; M{xVkXc>
5}eQaW48
/** the total page number */ C,r`I/;
privateint totalPage; ufCqvv>'
lKEX"KQ!
/** the number of current page */ kwHqvO!G
privateint currentPage; _Dj<Eu_
tKZ&1E
/** the begin index of the records by the current Px?Ao0)Z,
<'[Ku;m
query */ *J_iXu|
privateint beginIndex; %X9b=%'+
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x pTDYF
/** The default constructor */ GVG!sMmnX
public Page(){ rKzlK 'U
x=5P+_
} /zG+]
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/** construct the page by everyPage S= -M3fP~
* @param everyPage ] *-;' *
* */ Xlv#=@;O]
public Page(int everyPage){ Ad;S=h8:
this.everyPage = everyPage; IyS"
} a*Ss -y
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/** The whole constructor */ UP;Q= t
public Page(boolean hasPrePage, boolean hasNextPage, wmo{YS3t|
\Mb(6~nC
Sty!atEWT
int everyPage, int totalPage, `l/:NF
int currentPage, int beginIndex){ ?j/kOD0
this.hasPrePage = hasPrePage; '@TI48 J+
this.hasNextPage = hasNextPage; qL|
5-(P
this.everyPage = everyPage; \+k, :8s/
this.totalPage = totalPage; EZ"bW
this.currentPage = currentPage; f.oP
this.beginIndex = beginIndex; 5vTv$2@
} gYatsFyL
[ -ISR7D
/** p jKt:R}
* @return y" ^yYO
* Returns the beginIndex. G#H9g PY
*/ 99e*]')A%
publicint getBeginIndex(){ bj@xqAGl
return beginIndex; qy_%~c87
} NZLXN
Ge~q3"
/** I%@e@Dm,h
* @param beginIndex XGfzEld2"
* The beginIndex to set. =<{h^-j;a
*/ }[ ].\G\G
publicvoid setBeginIndex(int beginIndex){ 4`nqAX~'f
this.beginIndex = beginIndex; v f`9*x F
} |q;Al
z{
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/** !@u&{"{`
* @return +W9]ED
* Returns the currentPage. :pwa{P
*/ P5xI
publicint getCurrentPage(){ {Eu'v$c!
return currentPage; {h#6z>p"u2
} S'o ]=&
Xo Y7/&&
/** Z_FNIM0f
* @param currentPage Ah-8"`E
* The currentPage to set. yRC3
.[
*/ 7JI:=yY!>:
publicvoid setCurrentPage(int currentPage){ b^ sb]bZW
this.currentPage = currentPage; "u;YI=+
} JSgpb?(
HT"gT2U+
/** =EW3&+Lt
* @return xuUx4,Z
* Returns the everyPage. IaLMWoh
*/ R:/ha(+
publicint getEveryPage(){ p<KIF>rf|
return everyPage; 3B{[%#vO
} dQ9
ah
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/** rJQ=9qn\
* @param everyPage H4:ZTl_$
* The everyPage to set. }c%
pH{HI
*/ ;/'|WLI9
publicvoid setEveryPage(int everyPage){ LkBZlh_
this.everyPage = everyPage; tPU-1by$
} o G_C?(7>
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/** (a.1M8v+Sg
* @return 5M:D?9E+
* Returns the hasNextPage. KE.Dt
*/ &[_ZXVva~
publicboolean getHasNextPage(){ 3qi_]*dD
return hasNextPage; #cU^U#;= r
} C>X|VP|C
J}TfRrf
/** 5G(E&>~
* @param hasNextPage _BS
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* The hasNextPage to set. m`6VKp{YD
*/ -(#-I$z
publicvoid setHasNextPage(boolean hasNextPage){ :#u}.G
this.hasNextPage = hasNextPage; ^.goO]
} 5~+XZA#2
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/** 7I}P*%(f
* @return "DQ'C%sL9
* Returns the hasPrePage. g97]Y1g
*/ T3N"CUk
publicboolean getHasPrePage(){ 8W+5)m.tp
return hasPrePage; ?j{C*|yHO
} kl}Xmw{tJ
E0 l_--
/** gR Nv-^
* @param hasPrePage >w|*ei:@S
* The hasPrePage to set. gfy19c 9
*/ 8=;k"
publicvoid setHasPrePage(boolean hasPrePage){ XOy2lJ/
this.hasPrePage = hasPrePage; TDNf)Mm
} osHCg
qlsQ|/'D
/** N|:'XwL
* @return Returns the totalPage. kV&9`c+
* #sB,1"
*/ UiQEJXwnz
publicint getTotalPage(){ jz'<
return totalPage; L":bI&V?:
} x_MJJ(q8g
0g=`DSC<(
/** \Kavw
* @param totalPage A??@AP[7M
* The totalPage to set. 3
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*/ @jy41eIo
publicvoid setTotalPage(int totalPage){ y\c"b-lQX
this.totalPage = totalPage; Dg>^A
} K'5'}Lb5k
p(JlvJjo
} kH948<fk3
M+P$/Wk
`>lzlEhKV
BiwieF4x
!>$4]FkV
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 O4iC]5@
CE%_A[a
个PageUtil,负责对Page对象进行构造: 1zxq^BI
java代码: HMGB>
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/*Created on 2005-4-14*/ 'gMfN
package org.flyware.util.page; 2 QTZwx
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import org.apache.commons.logging.Log; 9~\kF5Q"
import org.apache.commons.logging.LogFactory; G$M9=@Ug
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/** .)tSg
* @author Joa +IFw_3$
* eU@Cr7@,|
*/ t=
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publicclass PageUtil { L1{GL #qV
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privatestaticfinal Log logger = LogFactory.getLog 6IcNZ!j98
u{<"NR h
(PageUtil.class); 3VO2,PCZ
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/** `>C<}xO
* Use the origin page to create a new page YIRZ+H<Q
* @param page "SxLN
8.:
* @param totalRecords [Nm4sI11
* @return %r\n%$@_
*/ C4$:mJ>y
publicstatic Page createPage(Page page, int DOS0;^f
#6v27:XK
totalRecords){ {7hLsK[])
return createPage(page.getEveryPage(), H`hnEOyLp
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page.getCurrentPage(), totalRecords); 4*n#yVb/
} !|hoYU>@2L
>et-{(G
/** CqMhk
* the basic page utils not including exception zE T^T5>:
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handler c,MOv7{x_
* @param everyPage Fxs;Fp
* @param currentPage 6 gL=u-2
* @param totalRecords JCx
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* @return page 5zJj]A
*/ q%n6K
publicstatic Page createPage(int everyPage, int d_UN0YT<
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currentPage, int totalRecords){ ]B"'}%>ez
everyPage = getEveryPage(everyPage); $4kH3+WJ
currentPage = getCurrentPage(currentPage); 2"P99$"
int beginIndex = getBeginIndex(everyPage, LsEXM-
<#=N
m0S$
currentPage); u-Ddq~;|
int totalPage = getTotalPage(everyPage, (
9!k#
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totalRecords); ,j;m!V
boolean hasNextPage = hasNextPage(currentPage, 9O`
m,t
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totalPage); $E<Esf$
boolean hasPrePage = hasPrePage(currentPage); o+`6LKg;
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returnnew Page(hasPrePage, hasNextPage, O<PO^pi
everyPage, totalPage, El_wdbbT
currentPage, oVA?J%EK
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beginIndex); f0<hE2
} ~CB[9D=
P./V6i<:
privatestaticint getEveryPage(int everyPage){ #/"8F O%~p
return everyPage == 0 ? 10 : everyPage; K8n4oz#z
} 3&u_A?;
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privatestaticint getCurrentPage(int currentPage){ 7{e{9QbJ4
return currentPage == 0 ? 1 : currentPage; =9oPowq
} C{sLz9
)vmA^nU>
privatestaticint getBeginIndex(int everyPage, int yKYUsp
S)QAXjH
currentPage){ F(4?tX T
return(currentPage - 1) * everyPage; Vd".u'r
} \!(
&PkLp4mQ
privatestaticint getTotalPage(int everyPage, int Nx{$}
4h5g'!9-g
totalRecords){ M02uO`Y9
int totalPage = 0; 4h@Z/G!T3
P\8@g U!uk
if(totalRecords % everyPage == 0) j4?@(u9;j
totalPage = totalRecords / everyPage; u` oq(?|
else o]nw0q?
totalPage = totalRecords / everyPage + 1 ; 6KD `oUx
g{W;I_P^9
return totalPage; iXyO(w4D
} 0sI1GhVR
4}`
privatestaticboolean hasPrePage(int currentPage){ ??n*2s@t
return currentPage == 1 ? false : true; : ^ 8
} ? uYu`Ojzr
nz9DLAt
privatestaticboolean hasNextPage(int currentPage, :2njp%
qwIa?!8o
int totalPage){ t){"Tfc:
return currentPage == totalPage || totalPage == V9ssH87#
SIbDj[s
0 ? false : true; ;<UW A.
} p>_;^&>&
ix#epuN
Vi4~`;|&b+
} ]f]<4HD=i
B||;'
c/_+o;Bc
5 H#W[^s"
&$`yo`
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。 %0? M?Jf
(`? y2n)~W
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 rP!#RzL
`DT3x{}_S
做法如下: ',GS#~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %,hV[[ @.
9;?UvOI;
的信息,和一个结果集List: /r12h|
java代码: $9S(_xdI&
g;ZxvR)ZJk
*D'$"@w3
/*Created on 2005-6-13*/ C/(M"j M
package com.adt.bo; Q5%#^ZdsTd
Z}|(FRVk
import java.util.List; OgF+OS
Ela-,(Glk
import org.flyware.util.page.Page; SZJ$w-<z
%lg=YGLQB
/** O@?kT;B
* @author Joa hDV20&hq
*/ _z[#}d;k
publicclass Result { iD= p\
?BhMjsy.
private Page page; |Yq$sU
t%530EB3
private List content; M>M`baM1
lY*[tmz)
/** M)sZSH.<O
* The default constructor D1nq2GwS
*/ XJ2^MF2BU
public Result(){ V21njRS
super(); m^x6>9,
} 3_q3Bk
vP+@z-O
/** @y31NH(
* The constructor using fields
^Q&u0;OJ
* P,sjo u^
* @param page Bo5ZZY
* @param content BcD&sQ2F
*/ G|\^{5
public Result(Page page, List content){ ]0L&v7[
this.page = page; tl'n->G>v
this.content = content; Ew3ibXD
} D/h/Y) Y
Qv-@Zt!8
/** $ cu00K
* @return Returns the content. fr!Pj(Q1
*/ ':R,53tjl
publicList getContent(){ v`1,4,;,qs
return content; N?X~ w <
} t#!yrQ..'G
_{jjgQJ5
/** "[:iXRu
* @return Returns the page. YIR
R=qpn
*/ J~(Wf%jM~
public Page getPage(){ @|'5n
return page; @]bPVG?d
} :NJ(r(QG>
Ngg?@pG0y
/** j1 =`|
* @param content TY(bPq
* The content to set. wb Iq&>p
*/ h~wi6^{&Y
public void setContent(List content){ z#F.xVg'
this.content = content; Y?534l)j
} F ]O$(7*
-Z-IF#%
/** -l}IZY
* @param page 0kDK~iT
* The page to set. MQ)L:R`L
*/ {,OS-g
publicvoid setPage(Page page){ Cye$H9 2
this.page = page; k=GG>]<i
} bqQq=SO
} -)vEWn$3<
jgS%1/&
KgN)JD>
0j(M*
sl
34!dYr%
2. 编写业务逻辑接口,并实现它(UserManager, ^t7x84jhL
R}mn*h6
UserManagerImpl) Z/rTVAs@r
java代码: ) _ I,KEe
SE7W F18A
5<L_|d)0"
/*Created on 2005-7-15*/ P,=+W(s9}
package com.adt.service; lnGq :-
=uDgzdDyE
import net.sf.hibernate.HibernateException; .WQ<jZt>
:fk2]{KTL
import org.flyware.util.page.Page; U}SXJH&&E
oUQ07z\C
import com.adt.bo.Result; 4em;+ >D6
$;G{Pyp
/** 09o~9z0
* @author Joa Q
!qrNa6
*/ )6~1 ^tD
publicinterface UserManager { K\XyZ
V#ev-\k}@
public Result listUser(Page page)throws P'MY[&|mM'
6mH/ m&
HibernateException; ,@z4I0cTi\
oPc\<$
} )rLMIk
.lhn;*Yi
S]sk7
|+ge8uu?C
juBw5U<
java代码: G,= yc@uq
l8K5k:XCU3
$N2SfyX7
/*Created on 2005-7-15*/ FI8Oz,
package com.adt.service.impl; )Z+{|^`kJ
~](fFa{
import java.util.List; fQ>4MKLw=d
:T3/yd62N
import net.sf.hibernate.HibernateException; \RQ='/H*
c^8o~K>w84
import org.flyware.util.page.Page; 4;`Bj:.
import org.flyware.util.page.PageUtil; HmK*b Z
TgU**JN)
import com.adt.bo.Result; m\/(w_/?
import com.adt.dao.UserDAO; zq5'i!s !0
import com.adt.exception.ObjectNotFoundException; m"c :"I6
import com.adt.service.UserManager; @&1Wyp
4\.V
/** h?\2_s
* @author Joa (wRBd
*/ W&:[r/8wA
publicclass UserManagerImpl implements UserManager { #$vRJ#S}U
7:=5"ScV
private UserDAO userDAO; URcR
2WM\elnA
/** $3=:E36K
* @param userDAO The userDAO to set. .'[/|4H
*/ 8|twV35
publicvoid setUserDAO(UserDAO userDAO){ uQLlA&I"
this.userDAO = userDAO; 3HyhEVR-#~
} 5H,G-
>zY \Llv
/* (non-Javadoc) wN37zPnV~
* @see com.adt.service.UserManager#listUser WKA'=,`v
J3S&3+2G
(org.flyware.util.page.Page) T#:F]=
*/ Iy
{U'a!
public Result listUser(Page page)throws P2n2Qt2
Y ?]G}5
HibernateException, ObjectNotFoundException { 9Z\z96O-
int totalRecords = userDAO.getUserCount(); guN4-gGDr<
if(totalRecords == 0) PX".Km p.
throw new ObjectNotFoundException ^c9ThV.v
<2
("userNotExist"); ?SY<~i<K-
page = PageUtil.createPage(page, totalRecords); Wf02$c0#K
List users = userDAO.getUserByPage(page); AZFWuPJo
returnnew Result(page, users); pt:;9hA
} X=qS"O 1
SA6hbcYk
} &J"YsY
FN"rZWM
5!fSW2N
RagiV6c
i%(yk#=V
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ].DY"
yYAnwf
询,接下来编写UserDAO的代码: 4 9w=kzo
3. UserDAO 和 UserDAOImpl: UFZ"C,
java代码:
AvRcS]@=
sV0Z
l^ 4OC
/*Created on 2005-7-15*/ p?rK`$U+J
package com.adt.dao; c]Unbm^w
vrcE]5(:s
import java.util.List; I"!'AI-
y~#\#w{
import org.flyware.util.page.Page; ^/KfH&E
5 Rz/Ri\c=
import net.sf.hibernate.HibernateException; 9\51Z:>
9EgP9up{6!
/** uIP
iM8(
* @author Joa O.:I,D&]
*/ < tQc_
publicinterface UserDAO extends BaseDAO { EnscDtf(
WEa>)@
publicList getUserByName(String name)throws 4UCwT1
>_Uj?F:
HibernateException; u7k|7e=xk
J9@}DB
publicint getUserCount()throws HibernateException; eOrYa3hQ
yKDZ+3xK]
publicList getUserByPage(Page page)throws gg8c7d:Q
G*\sdBW!k
HibernateException; jKt-~:
&telCg:
} ltEF:{mLe#
R#0{Wg0O)
RWE~&w G}
##~!M(c
agY5Dg7
java代码: ="lI i$>O
PRpE$`WK
$r"A@69^RS
/*Created on 2005-7-15*/ XM!M%.0WS
package com.adt.dao.impl; 3i(J on/p
~L){O*Z
import java.util.List; F50JJZ
Yq0# #__
import org.flyware.util.page.Page; 4$i} Xk#3
"A7<XN<
import net.sf.hibernate.HibernateException; ;C_ >
import net.sf.hibernate.Query; [aNhP;<
l:z};
import com.adt.dao.UserDAO; h2&y<Eg >
('HxHOh2
/** ;.0LRWcJ
* @author Joa q2Rf@nt
*/ =~",/I?
public class UserDAOImpl extends BaseDAOHibernateImpl a>(~ C'(<
BvI 0v:
implements UserDAO { ~>w:;M=sV8
++k J\N{
/* (non-Javadoc) AY@k-4
* @see com.adt.dao.UserDAO#getUserByName 1)Eq&ASB
^?sSx!:bZ
(java.lang.String) gUb
"3g0
*/ KT=a(QL
publicList getUserByName(String name)throws u7 u~
~,G]glu8
HibernateException { f\=6I3z
String querySentence = "FROM user in class Re\o
v x9
zi_[V@Es/
com.adt.po.User WHERE user.name=:name"; hOn
Query query = getSession().createQuery 4L$};L
[U']kt
(querySentence); }
Ab_o#Zy
query.setParameter("name", name); .> ,Z kS
return query.list(); 8'%+G
} gQ,4xTX
]wR6bEm7
/* (non-Javadoc)
T"B8;|
* @see com.adt.dao.UserDAO#getUserCount() }Oh5Nm)
*/ }M="oN~w
publicint getUserCount()throws HibernateException { G
"c/a8
int count = 0; ME,duY/>Q
String querySentence = "SELECT count(*) FROM AD,@,|A
ZgK@Fl*k
user in class com.adt.po.User"; R1~7F{FW
Query query = getSession().createQuery T5V$wmB\W
g.=!3e&z%
(querySentence); eoJFh
count = ((Integer)query.iterate().next fW[_+r]
Mi;Tn;3er
()).intValue(); #-A5Z;TD.
return count; }Uq/kei^P
}
TiTYs
" _mmR
M
/* (non-Javadoc) 8db6(Q~P
* @see com.adt.dao.UserDAO#getUserByPage s?HsUD$b
EtPgzw[#c9
(org.flyware.util.page.Page) ,qYf#fU#7
*/ "hfw9Qm
publicList getUserByPage(Page page)throws pM,#wYL
&9k"9
HibernateException { ]KzJ u`O%G
String querySentence = "FROM user in class jw/wcP
S[ i$e
com.adt.po.User"; T<_+3kw
Query query = getSession().createQuery ,Qga|n8C
^1()W,B~w
(querySentence); >&g2 IvDS
query.setFirstResult(page.getBeginIndex()) i^~sn `o
.setMaxResults(page.getEveryPage()); La@\q[U{@
return query.list(); *-+C<2"
} +~@7"
|d
xMLrLXy
} I<IC-k"Y
IwOfZuS
|YJ$c@
0,+EV,
tvv[$b&
至此,一个完整的分页程序完成。前台的只需要调用 _3*: y/M_
wrhBH;3
userManager.listUser(page)即可得到一个Page对象和结果集对象 ik8|9m4/
c,+iU R<
的综合体,而传入的参数page对象则可以由前台传入,如果用 4,o
%e,z
oA5<[&~<
webwork,甚至可以直接在配置文件中指定。 ;B,nzx(L
N;e}dwh&
下面给出一个webwork调用示例: D<lQoO+
java代码: tuX =o
&IIJKn|_
VZAuUw+M
/*Created on 2005-6-17*/ x;<oaT$X
package com.adt.action.user; tj`tLYOZ@-
IY-(-
a8
import java.util.List; dw@TbJ
h2im
sjf
import org.apache.commons.logging.Log; gNG0k$nP
import org.apache.commons.logging.LogFactory; 7uWJ6Wk
import org.flyware.util.page.Page; "TEBByO'
g|_HcaW
import com.adt.bo.Result; nNkyOaK*4
import com.adt.service.UserService; i7Y
s_8A"9
import com.opensymphony.xwork.Action; j=`y
@~
`NYF?%
/** GGYX!=]~
* @author Joa 7O;BS}Lv=
*/ =ip~J<sw&
publicclass ListUser implementsAction{ jAD+:@
yaCd4KP
privatestaticfinal Log logger = LogFactory.getLog v4nvZ6
WsG"x>1n
(ListUser.class); 8#NIs@DJ
&<\4q
private UserService userService; 9Ba%=
~N)( ^ 4
private Page page; OqAh4qa,$
n23%[#,r
privateList users; }Rf}NWU)|
5i}CzA96
/* xMO[3D&D
* (non-Javadoc) SaX,^_GY
* ~*,Ddwr0a
* @see com.opensymphony.xwork.Action#execute() ]{q-Y<{"
*/ -N /8Ho
publicString execute()throwsException{ /h.:br?M#P
Result result = userService.listUser(page); duZ|mT8Q==
page = result.getPage(); D;16}D
users = result.getContent(); ^+.+IcH
return SUCCESS; j\i;'t}8g
} ^VM"!O;h{
>x|A7iWn{,
/** VuJfo9 `E
* @return Returns the page. 1Ovx$*
*/ tkm~KLWV&7
public Page getPage(){ B` t6H
return page; MX4 :e>dtd
} &V ^
\S|VkPv
/** )zk?yY6
* @return Returns the users. *Dd(+NI
*/ [FeJ8P>z
publicList getUsers(){ ArEH%e
return users; X$j|/))
} ZYl-p]\*y
Sh~ 8jEk
/** S+Yy
* @param page /:*R -VdF
* The page to set. W[jW;uk
*/ ?-(w][MT\
publicvoid setPage(Page page){ .5Z,SGBf
this.page = page; dcrJ,>i}
} i"r.>X'Z
WL]Wu.k
/** Kc-A-P &Ry
* @param users qw
Kh,[]
* The users to set. `0n 7Cyed
*/ ^,ZvKA"}+/
publicvoid setUsers(List users){ fxtYo,;$
this.users = users; #Kb)>gzT
} W~+!"^<n
lhIr]'?l
/** }{w_>!ee
* @param userService ^}Dv$\;6
* The userService to set. LzEE]i
*/ $+)x)1
publicvoid setUserService(UserService userService){ +"N<-
this.userService = userService; nfd?@34"A2
} wZ\e3H z
} }~Kyw7?
o}AqNw60v
dTU.XgX)1^
4o)\DB?!
zM9) .D
H
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, Jb)eC?6O
u=ds]XP@
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 Sj]T{3mi
ui#1 +p3G
么只需要: [jtj~]&mO
java代码: Ik@Q@ T"
6&xW9' 6b:
]=
QCCC
<?xml version="1.0"?> 5sV/N] !
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _
/28Cw
T$8$9D_u
1.0//EN" "http://www.opensymphony.com/xwork/xwork- o`y*yucHI
+D{*L0$D"
1.0.dtd"> M@LaD 5
WHD/s
<xwork> [0,q7d?"
#*;fQ&p
<package name="user" extends="webwork- ` $x#_-Hn
y8(?:#ZC
interceptors"> w$_'xX(
uK&wS#uY
<!-- The default interceptor stack name Xm:gD6;9
'm p{O
--> dW=D]
<default-interceptor-ref |{|r?3
Zn*CJNB
name="myDefaultWebStack"/> EA@$^e[
J'Mgj$T $
<action name="listUser" ^>R| R1&
.1? i'8TF
class="com.adt.action.user.ListUser"> H|Fqc=qp
<param YvP"W/5
jiB>.te
name="page.everyPage">10</param> qu~"C,
<result Go+,jT-
$^+KR]\q
name="success">/user/user_list.jsp</result> fOjt` ~ToI
</action> D(ntVR
,DUQto
</package> [Jh))DIx
`GN5QLg#}0
</xwork> MKhL^c-
CH_Dat>
>p#d;wK4_
IOES3
`q{'_\gVt(
SIBIh- L
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 -0J<R;cVs
BMsy}08dQ
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 nF
y7gA|
uM!r|X)8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Ue\oIi
k49n9EX
SVEA
lJQl$Wx^
@_:?N(%(
我写的一个用于分页的类,用了泛型了,hoho hE`%1j2(
8 P y_Y>
java代码: jE5
9h
~Wd8>a{w
nsw8[pk
package com.intokr.util; aZCZ/
8\t7}8f
import java.util.List; H.G^!0j;
\c^jaK5
/** $A0]v!P~i-
* 用于分页的类<br> |q b92|?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^>}[[:( 6/
* FHPZQC8
* @version 0.01 *E q7r>[
* @author cheng uC ;PP=z
*/ 8i$`oMv[y
public class Paginator<E> { b0CaoSWo
privateint count = 0; // 总记录数 0lq4
privateint p = 1; // 页编号 aZ0iwMK
privateint num = 20; // 每页的记录数 &XTd[_VW!
privateList<E> results = null; // 结果 FJH8O7
TZ_'nB~
/** iYs?B0*JWK
* 结果总数 %iFIY=W
*/ 4!W?z2ly~R
publicint getCount(){ MBrVh6z>
return count; |y=F (6Z
} BJ2W}R
l]=$<
publicvoid setCount(int count){ s|`)'
this.count = count; p%tg->#L
} `5jB|r/
kF~e3A7C
/** f3B8,>
* 本结果所在的页码,从1开始 AS^$1i:
* 1MFpuPJk
* @return Returns the pageNo. tdK^X1
*/ }ZGpd9D
publicint getP(){ A{T@O5ucj
return p; &!fcL Jd
} k$- q;VI
eTHh
/** X.5LB!I)
* if(p<=0) p=1 J~`%Nj5>
* UeeV+xU
* @param p [,X,2
*/ ()JDjzQT
publicvoid setP(int p){ hvZR4|k>
if(p <= 0) 7OHw/-j\
p = 1; l[{}ZKZ
this.p = p; u6d~d\
} IcA~f@
1<e%)? G
/** K0a
50@B]
* 每页记录数量 xGk4KcxKs
*/ h(up1(x
publicint getNum(){ DMW:%h{
return num; 'mR+W{r
} $o H,:x?}
C{^@. 8:
/** 1yc@q8
* if(num<1) num=1 zjE4v-H:l
*/ >1zzDd_
publicvoid setNum(int num){ )S?}huX
if(num < 1) qRLypm
num = 1; fdW={}~
this.num = num; `vBa.)u
} X.|0E87
;Nij*-U4~
/** y$NG ..S
* 获得总页数 63$m& ]x
*/ :E*U*#h/
publicint getPageNum(){ Dw,f~D$+ic
return(count - 1) / num + 1; O,#[m:Ejb
} OO>2oH
BT0hx!Ti
/** Ry3 f'gx
* 获得本页的开始编号,为 (p-1)*num+1 ;O>fy:$'
*/ &i RX-)^u
publicint getStart(){ s50ln&2
return(p - 1) * num + 1; net9KX4\
} rfpxE>_|G
`;@4f|N9
/** INpub5
* @return Returns the results. LcF3P
4
*/ ="K>yUfcFl
publicList<E> getResults(){ {Wo7=aR
return results; rg.if"o
} xM\ApN~W
L;`t%1
public void setResults(List<E> results){ cw{[B%vw
this.results = results; { VO4""m
} qI@_
nrBitu,
public String toString(){ ?C3cPt"
StringBuilder buff = new StringBuilder lsCh K
5;Xrf=
(); =oJiNM5_u
buff.append("{"); 9_{!nQC.g
buff.append("count:").append(count); FeLP!oS>
buff.append(",p:").append(p); ba13^;fm#
buff.append(",nump:").append(num); ^EOjq
buff.append(",results:").append Y2n*T
KXI,
63=m11Z4
(results); ) /'s&
D
buff.append("}"); *2F}e4v
return buff.toString(); P_U-R%f
} ~JpUO~i/
UEUTu}4y
} ZD(gYNi
.EO1{2=
9K!='u`