Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 fxcc<h4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =uHnRY
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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 %r\n%$@_
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Dim>
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。 #6v27:XK
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分页支持类: ;bzX%f?|G
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java代码: gV;H6"
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package com.javaeye.common.util; /6uT6G+(z}
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import java.util.List; /*FH:T<V
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publicclass PaginationSupport { Cwa^"r3P1
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publicfinalstaticint PAGESIZE = 30; hXIro
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privateint pageSize = PAGESIZE; |077Sf|
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privateList items; 'NjzgZ~]P
7,qYV}
privateint totalCount; :$;Fhf<5
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privateint[] indexes = newint[0]; 7w:ef0S
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privateint startIndex = 0; GYxM0~:$k
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public PaginationSupport(List items, int ]B"'}%>ez
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totalCount){ !)"%),>}o
setPageSize(PAGESIZE); RcG0 8p.)
setTotalCount(totalCount); -H^oXeN
setItems(items); mYN7kYR}<`
setStartIndex(0); <#=N
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} /@ !CKh`
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public PaginationSupport(List items, int E:sz$\Ht)
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totalCount, int startIndex){ "I?Am&>'
setPageSize(PAGESIZE); GcIDG`RX
setTotalCount(totalCount); \6n!3FLl
setItems(items); ZX!r1*c
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setStartIndex(startIndex); $n^MD_1!
} @bM2{Rh:
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public PaginationSupport(List items, int sIG7S"k>p
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totalCount, int pageSize, int startIndex){ b5$JfjI
setPageSize(pageSize); [ylsz?
setTotalCount(totalCount); nkxzk$
setItems(items); Hgeg@RP
Q
setStartIndex(startIndex); O RGD
} >z;[2n'
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publicList getItems(){ w\54j)rb
return items; P./V6i<:
} S=R7`a<.5
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publicvoid setItems(List items){ W>r#RXmh
this.items = items; ZUz ^!d
} Re:jVJgBz
6:GTD$Uz.
publicint getPageSize(){ 7{e{9QbJ4
return pageSize; 1c3TN#|)W
} HX'FYt/?t
N8qDdr9p?c
publicvoid setPageSize(int pageSize){ 8h3=b[
this.pageSize = pageSize; V@>r*7\F
} GRb*EeT
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publicint getTotalCount(){ S6}@I ,Q
return totalCount; ,fK3ZC
} Q9I
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publicvoid setTotalCount(int totalCount){ }I3gU
if(totalCount > 0){ G+B~Ix-
this.totalCount = totalCount; M02uO`Y9
int count = totalCount / a#mNE*Dg
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pageSize; ]\/tVn.'
if(totalCount % pageSize > 0) jV.g}F+1m
count++; ^~{$wVGa
indexes = newint[count]; a+hd(JX0~
for(int i = 0; i < count; i++){ o]nw0q?
indexes = pageSize * `cPywn@uGZ
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i; ?$f)&O
} uwRr LF
}else{ fLV"T_rk
this.totalCount = 0; %6AW7q
t
} 4}`
} R'kyrEO
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publicint[] getIndexes(){ d,8mY/S>w
return indexes; e[sK@jX6
} |F9z,cc"
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publicvoid setIndexes(int[] indexes){ :2njp%
this.indexes = indexes; e]jH+IR:>
} 4w#``UY)'
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publicint getStartIndex(){ XU+<?%u}z
return startIndex; vG \a1H
} SQeRSz8bK4
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publicvoid setStartIndex(int startIndex){ `ptj?6N-
if(totalCount <= 0) n@ w^V
this.startIndex = 0; sAg Kg=)
elseif(startIndex >= totalCount) P&Pj>!T5
this.startIndex = indexes mv5n4mav
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[indexes.length - 1]; V5p=
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elseif(startIndex < 0) :>p8zG
this.startIndex = 0; 3Tn)Z1o
else{ 5 H#W[^s"
this.startIndex = indexes \rVQQ|l
7'
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[startIndex / pageSize]; =)hVn
} p7:{^
} O?<&+(uMTT
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publicint getNextIndex(){ Oy 2+b1{
int nextIndex = getStartIndex() + j5
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+ >cBVx6
pageSize; )K'N(w
if(nextIndex >= totalCount) aZEn6*0B
return getStartIndex(); zG e'*Qei
else /r12h|
return nextIndex; v)2M1
} `vc
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publicint getPreviousIndex(){ S(\9T1DVe
int previousIndex = getStartIndex() - W>q HFoKa
z,{<Nm7&F
pageSize; Q5%#^ZdsTd
if(previousIndex < 0) wH~kTU2br
return0; 0\2\*I}?
else K\vSB~{[
return previousIndex; ['%69dPh
} xoOJauSX1
U%h);!<
} xQw7 :18wQ
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抽象业务类 z5W@`=D
java代码: c\% r38
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/** P>9aI/d9
* Created on 2005-7-12 h^j?01*Et
*/ 1^i Pji/
package com.javaeye.common.business; M>M`baM1
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import java.io.Serializable; %T7nO %p
import java.util.List; 5s{ABJ\@V
KFa_
import org.hibernate.Criteria; 1xv8gC:6
import org.hibernate.HibernateException; `GXkF:f=
import org.hibernate.Session; ?YeWH
WM
import org.hibernate.criterion.DetachedCriteria; IF]lHB
import org.hibernate.criterion.Projections; vP+@z-O
import 6i0A9SN
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org.springframework.orm.hibernate3.HibernateCallback; e)E$}4
import w,Ee>cV]a
^!q?vo\j|
org.springframework.orm.hibernate3.support.HibernateDaoS ;W>Y:NCrp
^( Rvk
upport; -R{V-
y1=NF
import com.javaeye.common.util.PaginationSupport; b,KcBQ.
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public abstract class AbstractManager extends 8BvonYt=8
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HibernateDaoSupport { u !!X6<
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privateboolean cacheQueries = false; wCk~CkC?
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privateString queryCacheRegion; f@co<iA
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publicvoid setCacheQueries(boolean gNG r!3*)w
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cacheQueries){ \p%3vRwS%p
this.cacheQueries = cacheQueries; sZ?mP;Q
} @,XSs
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publicvoid setQueryCacheRegion(String
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queryCacheRegion){ :$+-3_oLMQ
this.queryCacheRegion = @|'5n
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queryCacheRegion; t20PP4FWM
} ^*\XgX
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publicvoid save(finalObject entity){ fb da
getHibernateTemplate().save(entity); LSQz"Ll
l
} TY(bPq
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publicvoid persist(finalObject entity){ xJ2*LM-
getHibernateTemplate().save(entity); "`[!L z
} tTU=+*Io
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publicvoid update(finalObject entity){ GA`PY-Vs)
getHibernateTemplate().update(entity); e*j.
} ZtHm\VTS
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publicvoid delete(finalObject entity){ 1wW)tNKIF
getHibernateTemplate().delete(entity); /k"`7`!
} _20#2i&
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publicObject load(finalClass entity, w{k)XY40sW
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finalSerializable id){ Cye$H9 2
return getHibernateTemplate().load ={?vAb:
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(entity, id); OIl#DV.
} ;+1RUv
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publicObject get(finalClass entity, t*@z8<H
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finalSerializable id){ +y 87~]]
return getHibernateTemplate().get WL+]4Wiz
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(entity, id); w-@6|o,S
} 'Peni1_
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publicList findAll(finalClass entity){ g,:j/vR
return getHibernateTemplate().find("from _Jv
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" + entity.getName()); SE7W F18A
} ASPy
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publicList findByNamedQuery(finalString U:F/iXz
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namedQuery){ dz>;<&2Z
return getHibernateTemplate a}Sd W
PA w-6;
().findByNamedQuery(namedQuery); ,<DB&&EV8
} (z$r :p
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publicList findByNamedQuery(finalString query, ;6
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finalObject parameter){ 20rkKFk*
return getHibernateTemplate {G*A.$-d
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().findByNamedQuery(query, parameter); PCn Q_A-Q
} PM":Vd/
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publicList findByNamedQuery(finalString query, ;IK[Y{W/
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finalObject[] parameters){ [Pe#kzLX
return getHibernateTemplate $(Ugtimdv
qNyzU@
().findByNamedQuery(query, parameters); /WPv\L
} ;O 0+,
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publicList find(finalString query){ vILy>QS)
return getHibernateTemplate().find "!K'A7.^
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(query); 9x+<Ik
} qC!&x,}3
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publicList find(finalString query, finalObject $>U#
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parameter){ `IINq{Zk
return getHibernateTemplate().find FI8Oz,
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(query, parameter); [~D|peM3
} :`)~-`_
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public PaginationSupport findPageByCriteria PN+G:Qv
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(final DetachedCriteria detachedCriteria){ g/=K.
return findPageByCriteria t0:AScZY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); N?dvuB
} {5*|C-WWtG
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public PaginationSupport findPageByCriteria 0^'B3$>
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(final DetachedCriteria detachedCriteria, finalint R6 XuA(5
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startIndex){ Kt>X[o3m,
return findPageByCriteria ~#\i!I;RY}
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(detachedCriteria, PaginationSupport.PAGESIZE, ^0W(hA
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startIndex); &p<(_|Af
} BcA31%
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public PaginationSupport findPageByCriteria #$vRJ#S}U
xr(|*
(final DetachedCriteria detachedCriteria, finalint hM@\RPsY
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pageSize, 2Ha5yaTL
finalint startIndex){ iV.p5FD
return(PaginationSupport) .'[/|4H
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getHibernateTemplate().execute(new HibernateCallback(){ xa( m5P
publicObject doInHibernate {mE! Vf
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(Session session)throws HibernateException { O\;= V`z-
Criteria criteria = !/K8xD$
r^$~>!kZ|
detachedCriteria.getExecutableCriteria(session); ~c{:DM
int totalCount = c.H?4j7ga
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((Integer) criteria.setProjection(Projections.rowCount LE?u`i,e=+
!a1i Un9
()).uniqueResult()).intValue(); VS?@y/\In
criteria.setProjection `29TY&p+"
'!vc/Hw
(null); LU!1s@
List items = -'rj&x{Q)U
")s!L"x
criteria.setFirstResult(startIndex).setMaxResults d_}a`H
HW=xvA+
(pageSize).list(); "C%!8`K{a*
PaginationSupport ps = D1,O:+[;.
Kn+=lCk
new PaginationSupport(items, totalCount, pageSize, b`cYpcs
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startIndex); Mj0Cat=
return ps; d&:H&o)T!
} >Pe:I
}, true); ;kaHN;4?
} {7Cx#Ewd
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public List findAllByCriteria(final Q 882B1H
r
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DetachedCriteria detachedCriteria){ 0rMqWP
return(List) getHibernateTemplate .")b?#K
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().execute(new HibernateCallback(){ &yH#s
8^8
publicObject doInHibernate nYv#4*
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(Session session)throws HibernateException { i%(yk#=V
Criteria criteria = `rWB`q|i<
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detachedCriteria.getExecutableCriteria(session); 6i@ub%qq
return criteria.list(); 4 9w=kzo
} Oo%!>!Lt,
}, true); 3
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} AfWl6a?T8:
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public int getCountByCriteria(final #!!AbuhzK{
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DetachedCriteria detachedCriteria){ 4E"d /
Integer count = (Integer) ='/Z;3jt]x
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[
getHibernateTemplate().execute(new HibernateCallback(){ !Cj(A"uqY
publicObject doInHibernate }6~)bLzI}
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(Session session)throws HibernateException { zi!#\s^
Criteria criteria = t/:w1rw
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detachedCriteria.getExecutableCriteria(session); Rlg#z4m
return m^$5K's&
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criteria.setProjection(Projections.rowCount oW'POAr
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()).uniqueResult(); , p0KLU\-
} EnscDtf(
}, true); <*@~n- R$
return count.intValue(); $^vP<
} ;e;\q;GP
} NXgRNca
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用户在web层构造查询条件detachedCriteria,和可选的 1k>naf~O
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )*[
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PaginationSupport的实例ps。 d7~j^v)=^
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ps.getItems()得到已分页好的结果集 NiTJ}1 l
ps.getIndexes()得到分页索引的数组 )1_(>|@oi
ps.getTotalCount()得到总结果数 nUqy1(
ps.getStartIndex()当前分页索引 )Xno|$b5Eo
ps.getNextIndex()下一页索引 '0Zm#g
ps.getPreviousIndex()上一页索引 XV2=8#R
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*-z4 <LAa
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A7'b Nd6f9
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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 i`~~+6`J
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一下代码重构了。 Yq0# #__
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我把原本我的做法也提供出来供大家讨论吧: $I(}r3r
D Q 5W6W
首先,为了实现分页查询,我封装了一个Page类: <3Fz>}V32
java代码: l:z};
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/*Created on 2005-4-14*/ EW;1`x
package org.flyware.util.page; ;.0LRWcJ
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/** b Fn(w:1Q
* @author Joa PSEWL6=]N
*
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*/ w -dI<s
publicclass Page { [|z'"Gk{
W gZ@N
/** imply if the page has previous page */ ".M:`BoW4
privateboolean hasPrePage; lbofF==(
z`@z
/** imply if the page has next page */ 82.HH5Z{
privateboolean hasNextPage; OequU'j
)]}$
/** the number of every page */ t[ q3{-
privateint everyPage; . =R=cA7
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/** the total page number */ .pKN4
privateint totalPage; z"3H{ A
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/** the number of current page */ +WdL
privateint currentPage; r"[L0Cbb
fU`T\
/** the begin index of the records by the current /'"R Mq
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query */ /=-h:0{M
privateint beginIndex; 8'%+G
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/** The default constructor */ X_!$Pk7ma
public Page(){ _;VYFs
.Map
} K_FBy
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/** construct the page by everyPage O E]~@eU
* @param everyPage CL )%p"[x
* */ {~"Em'}J
public Page(int everyPage){ YiO3<}Uf
this.everyPage = everyPage; U#$:\fT
} xT/9kM&}L
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/** The whole constructor */ .:SfMr;G
public Page(boolean hasPrePage, boolean hasNextPage, pdy+h{]3
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G*=H;Upi
int everyPage, int totalPage, 4(;20(q]
int currentPage, int beginIndex){ Upu%.[7
this.hasPrePage = hasPrePage; /:^tc/5U]
this.hasNextPage = hasNextPage; h4h d<,
this.everyPage = everyPage; #W.bZ]&WA
this.totalPage = totalPage; |:}L<9Sq
this.currentPage = currentPage; 0x6@{0
this.beginIndex = beginIndex; }:"R-s
} ELD
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/** m9uUDq#GJ
* @return tPA"lBS !
* Returns the beginIndex. HN^w'I'bp
*/ :
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publicint getBeginIndex(){ @!Y.935/0
return beginIndex; ?!rU
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} z[%[bs2{
Aw5K3@Ltz
/** QZz&1n
* @param beginIndex nWd:>Ur
* The beginIndex to set. "NlRSc#
*/ $F<%Jl7_Z
publicvoid setBeginIndex(int beginIndex){ `yy%<&
this.beginIndex = beginIndex; <'VA=orD
} /^NJ)9IB
0;'j!`l9
/** ))$ CEh"X
* @return *?s/Ho &'
* Returns the currentPage. (1OW6xtfG
*/ ;k-g_{M
publicint getCurrentPage(){ 5BZ+b_A>VV
return currentPage; EwC5[bRjUp
} }`?7\\6
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/** tP -5
* @param currentPage % 1OC#&
* The currentPage to set. hwc:@'
*/ 6
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publicvoid setCurrentPage(int currentPage){ uF.Q " ,<
this.currentPage = currentPage; elNB7%Y/
} iz,]%<_PE
l A 0-?k
/** ^V_ku@DY
* @return |)~Ex 9%ev
* Returns the everyPage. wbn^R'
*/ [9'|7fdU
publicint getEveryPage(){ -Cg`x=G;z
return everyPage; @263)`9G
} !^n1
eUi> Mp
/** )j$b9ZBk
* @param everyPage p|xs|O6{
* The everyPage to set. wV7@D[8
*/ ':5Trx
publicvoid setEveryPage(int everyPage){ xn0s`I[
this.everyPage = everyPage; 't||F1X~J
} >|y>e{P
XL{{7%j
/** HCI'q\\
* @return yIn/Y 0No
* Returns the hasNextPage. 8ct+?-3g
*/ oFX"F0rx
publicboolean getHasNextPage(){ m4wPuW
return hasNextPage; Cb4d|yiS8
} @'6S[zU
b\<lNE!L
/** y 8Ei=[
* @param hasNextPage [1t\|v
* The hasNextPage to set. //ne']L
*/ ^Tb}]aHg
publicvoid setHasNextPage(boolean hasNextPage){ ^p{A!I!
this.hasNextPage = hasNextPage; =ip~J<sw&
} yBUZVqqDa
m~A[V,os
/** {o Q(<&Aw
* @return &<\4q
* Returns the hasPrePage. h0'8NvalQ
*/ (MF+/fi
publicboolean getHasPrePage(){ m70`{-O
return hasPrePage; s{x*~M$vt
} cij]&$;Q
5i}CzA96
/** cKvAR5|
* @param hasPrePage \;A50U|r
* The hasPrePage to set. # CP9^R S
*/ ~*,Ddwr0a
publicvoid setHasPrePage(boolean hasPrePage){ uD0(aqAZ
this.hasPrePage = hasPrePage; )&b}^1
} LS R_x$G+t
/h.:br?M#P
/** ~Hp#6+
* @return Returns the totalPage. A)O_es2
* M6o
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*/ ^+.+IcH
publicint getTotalPage(){ C}M0XW
return totalPage; hlSB7D"d
} (r#5O9|S
>x|A7iWn{,
/** r_!{!i3B
* @param totalPage LLXg
* The totalPage to set. Zpn*XG
*/ Y&1!Z*OL;
publicvoid setTotalPage(int totalPage){ yH0yO*RZ
this.totalPage = totalPage; vu
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} e{qp!N1!
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} 2fHIk57jP
!9ceCnwbNN
IL8'{<lM
{y+v-v/#
)zk?yY6
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 z<3}TD
:JTRRv
个PageUtil,负责对Page对象进行构造: L~?,6
java代码: 8S[<[CH
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/*Created on 2005-4-14*/ )n[`Z#
package org.flyware.util.page; ;Wfv+]n9
l"~h1xk~
import org.apache.commons.logging.Log; }QApeZd+q
import org.apache.commons.logging.LogFactory; !"o1ve`{
+Zty}fe
/** kG|>_5
* @author Joa )|59FOWg
* 5W:Gl?$S}
*/ ^=-*L
3f
publicclass PageUtil { k`iq<b
's7 SZ$(
privatestaticfinal Log logger = LogFactory.getLog M rH%hRV6R
qw
Kh,[]
(PageUtil.class); gOES2
4$2
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]2^
/** SzgY2+Qq
* Use the origin page to create a new page VfE^g\Ia
* @param page 7Dx .;
* @param totalRecords |RvpEy76
* @return $fj"*
*/ qI4R`P"
publicstatic Page createPage(Page page, int }{w_>!ee
+i q+
totalRecords){ :`Zl\!]E`o
return createPage(page.getEveryPage(), 2jrX
1VPN#Q!
page.getCurrentPage(), totalRecords); >FEQtD~F
} n)wpxR
#IL~0t
/** )n3biQL_
* the basic page utils not including exception 4%c7#AX[T
B9;,A;E};
handler 9cw4tqTm
* @param everyPage =Y=^]ayO/
* @param currentPage S*DBY~pZy
* @param totalRecords [<3Q$*Ew
* @return page [u9S+:7"
*/ B#Oc8`1Y
publicstatic Page createPage(int everyPage, int d@q t%r3;
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currentPage, int totalRecords){ /="D]K)%b8
everyPage = getEveryPage(everyPage); ^JF_;~C
currentPage = getCurrentPage(currentPage); fi-&[llg
int beginIndex = getBeginIndex(everyPage, 6&xW9' 6b:
XM5;AcD
currentPage); H?/cG_^y0
int totalPage = getTotalPage(everyPage, 7]HIE]#
_
/28Cw
totalRecords); K&"Pm9
boolean hasNextPage = hasNextPage(currentPage, );/5#b@<Y
RGPU~L
totalPage); e&a[k
boolean hasPrePage = hasPrePage(currentPage); >a anLLO
Spr:K,
returnnew Page(hasPrePage, hasNextPage, exrt|A]_[
everyPage, totalPage, )1tnZ=&
currentPage, 3K'o&>}L
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beginIndex); dO4U9{+
} c_8 mQ
;HLMU36q
privatestaticint getEveryPage(int everyPage){ ^2?O+ =,F
return everyPage == 0 ? 10 : everyPage; w\8rh\Mvh
} Y[8co<p
efAahH
privatestaticint getCurrentPage(int currentPage){ XtH_+W+O
return currentPage == 0 ? 1 : currentPage; +/_B/[e<>
} z&HN>7
Zn*CJNB
privatestaticint getBeginIndex(int everyPage, int ,aj+mlZd2
~PS2[5yo
currentPage){ Z=/L6Zb
return(currentPage - 1) * everyPage; |~"A:gf
} .1? i'8TF
: z,vJ~PW
privatestaticint getTotalPage(int everyPage, int Bc"}nSjH
<T2~xn
totalRecords){ R7;rBEt8
int totalPage = 0; ,;ruH^
BO\`m%8md
if(totalRecords % everyPage == 0) OaCj3d>
totalPage = totalRecords / everyPage; H/la'f#o%
else O
|I:[S},
totalPage = totalRecords / everyPage + 1 ; m&jt[
q
]R @:a/
return totalPage; (LvOsr~
} *p5T
X|n[9h:%
privatestaticboolean hasPrePage(int currentPage){ VFaK>gQ
return currentPage == 1 ? false : true; [@?.}!
} RO3e
)+{omQ7v
privatestaticboolean hasNextPage(int currentPage, ujp,D#xHP
L!Zxc~
int totalPage){ NVh>Q>B$_
return currentPage == totalPage || totalPage == 2,QApW_Y
kE(-vE9
0 ? false : true; QO`Sn N}
} K}*p(1$u
k-PRV8WO
PNxO\Rc
} O}iKPY8K
{aa,#B]i
JP% ;rAoJ
)*<d1$aM
g8qAJ4
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]=XL9MI
@_:?N(%(
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 v&/-&(+
zSvHv s
做法如下: i$<v*$.o
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 .$}zw|,q
C]cT*B^
的信息,和一个结果集List: aZCZ/
java代码: 5N</Z6f'o
n)7$xYuH
]be2jQx3
/*Created on 2005-6-13*/ \c^jaK5
package com.adt.bo; O
NzdCgY
kk./-G
import java.util.List; 3:gO7Uv
v@1Jhns
import org.flyware.util.page.Page; 7}7C0mV3
BCDf9]X
/** ]qG5Ne_
* @author Joa n~cm?"
*/ 8i$`oMv[y
publicclass Result { #:5g`Ch4,
~5qZs"ks
private Page page; E0%Y%PQ**{
jl%eO.
private List content; 1UWgOCc
EC\:uK
/** gK_[3FiKt
* The default constructor b6M)qt9R
*/ mztq7[&-
public Result(){ 3\~fe/z'I
super(); %lW:8ckL
} l{x#*~ga
BQmafpp`
/** .Eyk?"^
* The constructor using fields HSFf&|qqx
* gG> ^h1_o~
* @param page ?PtRb:RHt
* @param content -^yc yZ
*/ h/~BUg'
public Result(Page page, List content){ d'nuk#r
this.page = page; n&&U9sf?
this.content = content; 6? ly.h$
} #EK8Qe_
Mp}NUQHE
/** d(tf: @
* @return Returns the content. \5c -L_
*/ tdK^X1
publicList getContent(){ AsF`A"Cdw<
return content; 2G>
]W?>
} xJ5!`#=
k(Xv&Zn
/** 4^9_E&Fa
* @return Returns the page. yp'>+cLa
*/ A>@epCD
public Page getPage(){ 6u3(G j@
return page; >x0lSL0y
} 7}85o
J
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/** *%+buHe
* @param content f=Y9a$.:M
* The content to set. ;P#*R3
*/ \`# 0,pLr
public void setContent(List content){ HBGA
lZ
this.content = content; Upen/1 bA
} m3e49 bP
LZ: \V)5+
/** ZO$T/GE6%
* @param page %E_{L
* The page to set. @y&,e,3!
*/ X}^gmu<Vla
publicvoid setPage(Page page){ C^O^Jj5X%
this.page = page; K<(sqH
} 1<e%)? G
} >7Q7H#~w
6VE5C
g
,6pH *b$
qE=OQs9
$o H,:x?}
2. 编写业务逻辑接口,并实现它(UserManager, Ux]@prA q
^<+heX
UserManagerImpl) =LA@E&,j
java代码: )S?}huX
EOC"a}Cq-
y Dw!u[:
/*Created on 2005-7-15*/ L@GD$F=<0
package com.adt.service; VHNiTp
hKYPH?b%
import net.sf.hibernate.HibernateException; ;Bi{;>3
mr.DP~O:9p
import org.flyware.util.page.Page; ZeV)/g,w
*?Y6qalSy
import com.adt.bo.Result; yK3z3"1M?
4VgDN(n0@
/** t,nB`g?
* @author Joa Y.#+Yh[
*/ `;@4f|N9
publicinterface UserManager { e vuP4-[y
m"]ys#
public Result listUser(Page page)throws ,iUx'U
(7,Awf5D~
HibernateException; p60D{UzU
#CmBgxg+M
} |&vuK9q
CXZeL 1+
:_ox8xS4
3R {y68-S
W^f#xrq>
java代码: TVA1FD
O6]~5&8U.
W[s>TDc`v
/*Created on 2005-7-15*/ EM}z-@A>
package com.adt.service.impl; XT"c7]X
Gy%e%'
import java.util.List; 1O4"MeF
0
HmRl
import net.sf.hibernate.HibernateException; Q2Rj0E`
) /'s&
D
import org.flyware.util.page.Page; ^cm^JyS)
import org.flyware.util.page.PageUtil; ri
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g=Di2j{A
import com.adt.bo.Result; -f=hL7NW
import com.adt.dao.UserDAO; /jD'o>
import com.adt.exception.ObjectNotFoundException; KG$2u:n
import com.adt.service.UserManager; ig{5]wZ(
-s"lW 7N^
/** iXFaQ
* @author Joa 9K!='u`
*/ .2xkf@OP
publicclass UserManagerImpl implements UserManager {
2X_ef
5FxU=M1gF
private UserDAO userDAO; >.|gmo>b
@Rm/g#!h"
/** E3!twR*Aw
* @param userDAO The userDAO to set. iY-dM(_:]
*/ ,H*3_c&Q
publicvoid setUserDAO(UserDAO userDAO){ #ZA
YP
this.userDAO = userDAO; 30@ GFaab
} ^dqEOW
7_,gAE:kG
/* (non-Javadoc) .E&~]<
* @see com.adt.service.UserManager#listUser kns]P<g
SCij5il%
(org.flyware.util.page.Page) VzesqVx
*/ 5oS\uX|
public Result listUser(Page page)throws o6 /?WR 9
Cmj)CJ-
HibernateException, ObjectNotFoundException { q@:&^CS
int totalRecords = userDAO.getUserCount(); LxT ]-
if(totalRecords == 0) YVT^}7#
throw new ObjectNotFoundException DZue.or
}8HLyK,4
("userNotExist"); i7FEjjGtG
page = PageUtil.createPage(page, totalRecords); :z\STXq
List users = userDAO.getUserByPage(page); \+xsJbEV
returnnew Result(page, users); 4"sP= C
}
c'b,=SM
`c(@WK4
} rzu^br9X
;QYK {3R?
{/ta1&xyG
Z>l>@wN m
L6^h3*JyD
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 art{PV4-
]G:xT v8
询,接下来编写UserDAO的代码: r`2& o
3. UserDAO 和 UserDAOImpl: \
(,2^T'$J
java代码: H<
j+-u4b
t(Uoi~#[
#XsqTK_nk
/*Created on 2005-7-15*/ Q *he%@w
package com.adt.dao; y_6HQ:
wrbDbp1L
import java.util.List; (rJvE*
Gkl#s7'
import org.flyware.util.page.Page; Ot?rsr
fOVRtSls
import net.sf.hibernate.HibernateException; z?PF9QL1
B !XT:.+
/** }49?Z 3
* @author Joa uyj5}F+O
*/ ;c`B'
publicinterface UserDAO extends BaseDAO { `d8TA#|`
/y}
publicList getUserByName(String name)throws V+^\SiM
g=)@yZ3>v
HibernateException; ;bX{7j
.qZ<ROZ
publicint getUserCount()throws HibernateException; !>Xx</iD1
L|<Mtw
publicList getUserByPage(Page page)throws {'1,JwSmb
<6@Db$-
HibernateException; $Ix^Rm9c
KvQ9R!V
} du !.j
"jSn`
FB@G.f
yZ`\.GgC^&
(~jOtUyT
java代码: WI%,m~
`)'YU^s
L,i-T:Z~=
/*Created on 2005-7-15*/ }sFHb[I &
package com.adt.dao.impl; IoC,\$s,
OHU(?TBo
import java.util.List; >a<;)K^1
\?j(U8mB>
import org.flyware.util.page.Page; *d=pK*g
@c.pOX[]m,
import net.sf.hibernate.HibernateException; %lBFj/B
import net.sf.hibernate.Query; }{$@|6)R
HkrNt/]
import com.adt.dao.UserDAO; N67m=wRx
FX{Sb"
/** ?IK[]=!
* @author Joa ||hd(_W8
*/ aePk^?KbB
public class UserDAOImpl extends BaseDAOHibernateImpl *`kh}
!>M: G:K
implements UserDAO { d/MMPge3
){v nmJJ%
/* (non-Javadoc) -{dwLl_
* @see com.adt.dao.UserDAO#getUserByName 7*sB"_U2
Qi9SN00F.
(java.lang.String) RW'QU`N[Y
*/ zR%#Q_
publicList getUserByName(String name)throws , vWcWT
/wQDcz
HibernateException { {J[0UZ6
String querySentence = "FROM user in class k{; 2*6b0
V[~/sc )
com.adt.po.User WHERE user.name=:name"; Lr`yl$6
Query query = getSession().createQuery (uSfr]89'
S;Vj5
(querySentence); [ACa<U/
query.setParameter("name", name); um/iK}O
return query.list(); 8"+Kz
} L!\I>a5C0G
cG.4%Va@s_
/* (non-Javadoc) +BESO
* @see com.adt.dao.UserDAO#getUserCount() Lx.X#n.]T
*/ ~MOIrF
publicint getUserCount()throws HibernateException { 9BP-Iet
int count = 0; -{HA+ YL H
String querySentence = "SELECT count(*) FROM 4oJ0,u
tlj^0
user in class com.adt.po.User"; ,a}+Jj{
Query query = getSession().createQuery 9Z}-%Z[,)
D ,nF0p
(querySentence); &U:;jlST9
count = ((Integer)query.iterate().next d;K,2
W+e
()).intValue(); ikUG`F%W
return count; 8< R#}
} W_%Dg]l
6:H@=fEv
/* (non-Javadoc) %5'6^bT
* @see com.adt.dao.UserDAO#getUserByPage tks1*I$S<
X4gs{kx}|
(org.flyware.util.page.Page) +5voAx!
*/ hDCR>G
publicList getUserByPage(Page page)throws |Gz(q4
~OXPn9qPp
HibernateException { "~XAD(T6
String querySentence = "FROM user in class alyWp
ol-U%J
com.adt.po.User"; 3:s!0ty"
Query query = getSession().createQuery G22u+ua
'vBuQinn
(querySentence); o^mW`g8[
query.setFirstResult(page.getBeginIndex()) #>}cuC@
.setMaxResults(page.getEveryPage()); T)MKhK9\Ab
return query.list(); P9BShC5
} r3'0{Nn+
8K'3iw>z
} G@s
rQum(
`#R[x7bA1
W2'u]1bs
&=~Jw5WK
f-^JI*hj
至此,一个完整的分页程序完成。前台的只需要调用 _vm ~yKId
p[>!;qI
userManager.listUser(page)即可得到一个Page对象和结果集对象 }Ge$?ZFH
RGsgT ^
的综合体,而传入的参数page对象则可以由前台传入,如果用 a0~LZQ?
.r4*?>
webwork,甚至可以直接在配置文件中指定。 N:_.z~>%
=A{F&:+a]
下面给出一个webwork调用示例: )vn{?Ulj
java代码: ;ry~x:7L7
Pd)mLs Jg
3VaL%+T$,
/*Created on 2005-6-17*/ 3%P<F>6
J
package com.adt.action.user; {{qu:(_g
pC^d-Ii
import java.util.List; MaN6bM
3s;^p,9
Y
import org.apache.commons.logging.Log; *mby fu0q
import org.apache.commons.logging.LogFactory; ;?4EVZ#o
import org.flyware.util.page.Page; }Y:V&4DW
%g: 6QS|
import com.adt.bo.Result; FN\*x:g
import com.adt.service.UserService; Xh+;$2l.B
import com.opensymphony.xwork.Action; 1
8%+ Hy=
GCZx-zD~>
/** 9eBD)tnw
* @author Joa 3N257]
*/ Lcb5^e?'Q
publicclass ListUser implementsAction{ Y7BmW+
zcGmru|k
privatestaticfinal Log logger = LogFactory.getLog TophV}@B`
wDR/Vr"f
(ListUser.class); VkFMr8@|
cDS\=Bf
private UserService userService; 5/8=Do](
Y
\ Gx|
private Page page; 2)hfYLi
`3g5n:"g\
privateList users; }k;wSp[3
7cB/G:{
/* :er(YWF:
* (non-Javadoc) F%P"T%|
* $7" Y/9Y
* @see com.opensymphony.xwork.Action#execute() 0nbY~j$A=
*/ (@m/j2z
publicString execute()throwsException{ H-\Ym}BGu
Result result = userService.listUser(page); w p\-LO~
page = result.getPage(); Qp7h|<
users = result.getContent(); 1J([*)
return SUCCESS; =WT&unw}
} o%7-<\qS
Jr5dw=B gw
/** ;.'?(iEB
* @return Returns the page. ulE5lG0c
*/ X!_&%^L'
public Page getPage(){ FY<Q|Ov
return page; {7jl) x3l
} X$e*s\4
!0dQfj^_
/** =^1jVaAL
* @return Returns the users. |sd G<+
*/ NOg/rDs'{
publicList getUsers(){ aVCPaYe^
return users; yIhPB8QL
} s]]lB018O\
;4l8Qg
7
/** ?VlGTMaS+
* @param page ~UJ.A<>Fh
* The page to set. HjIIhl?UY
*/ ~m_{&,CA.
publicvoid setPage(Page page){ `;Ho<26
this.page = page; yts@cd`$
} R2v9gz;W
!(
>U3N
/** LaO8)lqR
* @param users a*-9n-U@[k
* The users to set. ( <YBvpt4>
*/ EsGf+-}|!0
publicvoid setUsers(List users){ L&c
&
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this.users = users; :.4O
Hp1
} T%%
0W J
9dq"x[
/** }4p)UX>aWT
* @param userService Li]bU
* The userService to set. b"WF]x|^
*/ b"uO BB
publicvoid setUserService(UserService userService){ ~P#mvQE)
this.userService = userService; 0N^+d,Xt.
} ltfKqY-
} <3!Al,!ej@
)by7[I0v
Tf~eH!~0
{.542}A
>ei~:z]R
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, aX`uF<c9
V:w%5'^3
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 ?TeozhUY
y{/7z}d
么只需要: 0KnL{Cj
java代码: M^[;{p2uZ
_tJt
eDRY
] L97k(:Ib
<?xml version="1.0"?> hH 5}%/vF
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork o`QNZN7/}
x(._?5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w+/`l*
Z/%FQ
1.0.dtd"> kV+^1@"
Wk\(jaL%
<xwork> GA[Ebzi
ydy TDn
<package name="user" extends="webwork- g]lEG>y1R
p;>A:i
interceptors"> u
[._RA
n74\{`8]o
<!-- The default interceptor stack name y QClq{A
JD#x+~pb,8
--> h <e
<default-interceptor-ref <mQXS87
db~^Gqv6k
name="myDefaultWebStack"/> 5>I-? Ki
JcWp14~e
<action name="listUser" 4d`YZNvZW/
qFD ZD)K
class="com.adt.action.user.ListUser"> _;BwP
<param 1(-!TJ{
pASX-rb
name="page.everyPage">10</param> 9a=Ll]=\
<result !\X9$4po@
x=t(#R m
name="success">/user/user_list.jsp</result> 3Do0?~n
</action> >x{("``D0y
)GkJ%o#H2
</package> S3\NB3@qC&
Ea&|kO|
</xwork> 5Jbwl$mZ
8cG?p
x="Wqcnj{
oT-gZedW(
m<h%BDSzr{
1(gs({
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 {4D`VfX_
=vbG'_[7
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。 053bM)qW
uZC=]Ieh
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 rP:g`?*V
:j]1wp+
_#u\ar)
f' ?/P~[
Q#\Nhc
我写的一个用于分页的类,用了泛型了,hoho d5$D[,`1
'OsZD?W{
java代码: 8M99cx*K
fOV_ >]u
lI<jYd
0fZ
package com.intokr.util; GGp.u@\r
uzBQK
import java.util.List; sp,-JZD
oX|T&"&
/** e9o\qEm
* 用于分页的类<br> xqt?z n
* 可以用于传递查询的结果也可以用于传送查询的参数<br> M7TLQqaF
* 2!{D~Gfl=
* @version 0.01 fB8, )&
* @author cheng #7]Jz.S
*/ ,U~A=bsa
public class Paginator<E> { BpZ~6WtBq
privateint count = 0; // 总记录数 lL}NiN-)t
privateint p = 1; // 页编号 'X;cgAq8(
privateint num = 20; // 每页的记录数 (`1io
privateList<E> results = null; // 结果 G-d7}Uz?
pey=zR!
/** h}
`v0E
* 结果总数 l=E86"m
*/ A7%d
publicint getCount(){ lU{)%4e`
return count; n 9B5D:.G
} fpR|+`k
PVI Oe}N
publicvoid setCount(int count){ 6KMO*v
this.count = count; ,<v0(
} wZ(1\
M(
fz(YP=@ZnP
/** #EH=tJgO|J
* 本结果所在的页码,从1开始 "`>6M&`U
* 0P$1=oK
* @return Returns the pageNo. 8A#,*@V[
*/ ~CNB3r5R
publicint getP(){ @G4Z
return p; 5#GMp
} kelBqJ-,p
`
,\b_SFg
/** ("8 Hku?
* if(p<=0) p=1 fx;rMGa
* )x6&Y
* @param p t7f(%/] H0
*/ > Vm}u`x
publicvoid setP(int p){ "wgPPop
if(p <= 0) ^&qK\m_A
p = 1; ,b*?7R
this.p = p; CD&a_-'z$K
} $94lF~
y\T$) XGV
/** Nx 42k|8
* 每页记录数量 g88k@<Y
*/ jZA1fV
publicint getNum(){ tm~9XFQ<
return num; 0>28o.
} Rw?w7?I
)]fsl_Yq
/** 3Bl|~K;-
* if(num<1) num=1 Z>g72I%X
*/ "V[j&B)P
publicvoid setNum(int num){ w!m4>w
if(num < 1) T8S&9BM7
num = 1; L1SX2F8
this.num = num; ?w:\0j5~
} k4']q
i]ZGq7YJ%
/** U1YqyG8
* 获得总页数 .RroO_H
*/ 7h\is
publicint getPageNum(){ f Fi=/}
return(count - 1) / num + 1; NfoHQU<n
} > "hP
Ti? "Hr<W
/** m6i ,xn
* 获得本页的开始编号,为 (p-1)*num+1 Qsbyy>o)
*/ QNbZ)
publicint getStart(){ nE]rPRU}[
return(p - 1) * num + 1; YuhfPa
} n*\o. :f
Ae2N"%Ej
/** .q2r!B
* @return Returns the results. S)EF&S(TC
*/ <V^o.4mOg>
publicList<E> getResults(){ HM% +Y47a
return results; U^_\V BAk
} 1K/HVj+'.
?8O5%IrJ
public void setResults(List<E> results){ g:!U,<C^a
this.results = results; (-S^L'v62v
} z};|.N}
ja9u?UbW
public String toString(){ ]!TE
StringBuilder buff = new StringBuilder bPTtA;u
dk7x<$h-h0
(); Uh.swBC n
buff.append("{");
:q/s%`ob
buff.append("count:").append(count); o33t~@ RX
buff.append(",p:").append(p); w[GEm,ZC
buff.append(",nump:").append(num); iQO4IT
buff.append(",results:").append "~VKUvDu
T={!/y+
(results); k~)CJ6}
buff.append("}"); !60U^\
return buff.toString(); ]Gi&:k
} &<><4MQ
M[qhy.
} _n:RA)4*
>a975R*g
\:@6(e Bh