Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Ad[-YT
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;-59#S&?tB
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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 o}BaZ|iZ2
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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 PM{kiz^
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分页支持类: wNn6".S
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java代码: s<:J(gD
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package com.javaeye.common.util; i9Qx{f88
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import java.util.List; AyddkjX
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publicclass PaginationSupport { mU;TB%#)
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publicfinalstaticint PAGESIZE = 30; dbw`E"g
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privateint pageSize = PAGESIZE; E$gcd#rT
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privateList items; Q!c*2hI
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privateint totalCount; I<DS07K
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privateint[] indexes = newint[0]; I%|W
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privateint startIndex = 0; HA| YLj?|g
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public PaginationSupport(List items, int YDP<
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totalCount){ vO 3fAB
setPageSize(PAGESIZE); 2|+**BxHD
setTotalCount(totalCount); e(cctC|l
setItems(items); p tMysYT'
setStartIndex(0); vtmvvv
} N]gdS]pP2{
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public PaginationSupport(List items, int ?_IRO|
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totalCount, int startIndex){ C]82Mt
setPageSize(PAGESIZE); Jjv,
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setTotalCount(totalCount); 9M<{@<]dm
setItems(items); d+$a5 [^9
setStartIndex(startIndex); bX8Bn0#a+
} b2hB'!m
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public PaginationSupport(List items, int V1M oW;&
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totalCount, int pageSize, int startIndex){ A#*0mJ8IK
setPageSize(pageSize); mV6\gR[h
setTotalCount(totalCount); ht` !@B
setItems(items); \xwE4K
setStartIndex(startIndex); +c?1\{M
} XDU&Z2A
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publicList getItems(){ 7Q2"]f,$CQ
return items; x,pzX(
} L"9,K8
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publicvoid setItems(List items){ qlO(z5Ak
this.items = items; Z8Qmj5'[
} Ry8@U9B6,t
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publicint getPageSize(){ y]yp8Bs+
return pageSize; s+l)Q
} d
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publicvoid setPageSize(int pageSize){ D3N\$ D
this.pageSize = pageSize; 6Dwj^e0
} _Uc le
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publicint getTotalCount(){
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return totalCount; Nw*
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} ND77(I$3s
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publicvoid setTotalCount(int totalCount){ X2v|O3>/N
if(totalCount > 0){ @#xh)"}
this.totalCount = totalCount; A46Xei:Ow
int count = totalCount / f
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pageSize; k%Jv%m}aB
if(totalCount % pageSize > 0) 4vQ]7`I.f
count++; sz9C':`W
indexes = newint[count]; Z7lv|m&
for(int i = 0; i < count; i++){ T_i]y4dg
indexes = pageSize * fo@2@
0
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i; '#L.w6<B
} \L Gj]mb1
}else{ V*U{q%p(
this.totalCount = 0; Ey4%N`H-^
}
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} x 8|sdZFxo
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publicint[] getIndexes(){ HG{r\jh
return indexes; W{B)c?G]
} ~ (I'm[
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publicvoid setIndexes(int[] indexes){ Hx5t![g2K!
this.indexes = indexes; ckG`^<
} 9)}Nx>K
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publicint getStartIndex(){ z)*7LI
return startIndex; >VIb|YA
} XR3=Y0YDf
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publicvoid setStartIndex(int startIndex){ kwF4I)6
if(totalCount <= 0) 1w*DU9f
this.startIndex = 0; U 51C /A
elseif(startIndex >= totalCount) Q4i@y6z
this.startIndex = indexes ;w--fqxVl
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[indexes.length - 1]; LX5, _`B
elseif(startIndex < 0) ]#x!mZ!
this.startIndex = 0; b+7!$
else{ Y=94<e[f"
this.startIndex = indexes n o).70K
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[startIndex / pageSize]; KElzYZl8
} 99)m d
} 3z5w}qN]M
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publicint getNextIndex(){ >..C^8 "
int nextIndex = getStartIndex() + m$6u K0
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pageSize; ) bRj'*
if(nextIndex >= totalCount) )4u6{-|A
return getStartIndex(); AT$eTZ]M
else Cp {
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return nextIndex; Ky(=O1Ufu
} ixJ%wnz
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publicint getPreviousIndex(){ 6'E3Q=}d
int previousIndex = getStartIndex() - Teo&V
(^,4{;YQ5
pageSize; u6tD5Y
if(previousIndex < 0) !5FZxmUup
return0; y{{7)G
else Tp-<!^o4
return previousIndex; KPW2e2{4@
} :70n% 3a
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} 5^:N]Mp"
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抽象业务类 5BWO7F0v"
java代码: vuP.V#
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/** k(As^'>
* Created on 2005-7-12 1"7Rs}l7
*/ e&*< "WN
package com.javaeye.common.business; =gG_ %]``R
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import java.io.Serializable; b3$aPwv
import java.util.List; [
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import org.hibernate.Criteria; ,AX7~;hpq
import org.hibernate.HibernateException; I" AgRa
import org.hibernate.Session; 7NG^I6WP-
import org.hibernate.criterion.DetachedCriteria; 6@N?`6Bt
import org.hibernate.criterion.Projections; pyvZ[R9
import /1s|FI$-L
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org.springframework.orm.hibernate3.HibernateCallback; ~D[5AXV`^
import ? dD<KCbP,
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org.springframework.orm.hibernate3.support.HibernateDaoS HZ>8@AVa\
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upport; +aa( YGL
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import com.javaeye.common.util.PaginationSupport; gtizgUS7
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public abstract class AbstractManager extends Y bX3_N&
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HibernateDaoSupport { +vR$%
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privateboolean cacheQueries = false; {i}z|'!
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privateString queryCacheRegion; \=kre+g
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publicvoid setCacheQueries(boolean +1`Zu$|
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cacheQueries){ o'9K8q\1
this.cacheQueries = cacheQueries; aN\psg
} yW3X<
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publicvoid setQueryCacheRegion(String XI>|"*-l
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queryCacheRegion){ Woo2hg-ti
this.queryCacheRegion = lz=DP:/&
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queryCacheRegion; z?a<&`W
} 0H|U9
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publicvoid save(finalObject entity){ lP9XqQ(
getHibernateTemplate().save(entity); iymOq9
} (
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publicvoid persist(finalObject entity){ ;THb6Jz/+
getHibernateTemplate().save(entity); B5-G.Z
} %&D,|Yl6
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publicvoid update(finalObject entity){ #1>DV@^F
getHibernateTemplate().update(entity); |sa{!tKJ
} Sk*-B@!S
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publicvoid delete(finalObject entity){ m-{t%[Y
getHibernateTemplate().delete(entity); c^N'g!on
} vY+{zGF
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publicObject load(finalClass entity, 35 Y#eU2]
}Pu|%\
finalSerializable id){ ]e*Zx;6oi
return getHibernateTemplate().load xjm|ewo
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(entity, id); 76Drhh(
} Xp(e/QB
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publicObject get(finalClass entity, M5mCG
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finalSerializable id){ H9c
return getHibernateTemplate().get w"-'
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(entity, id); *b{C`[
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} c5>'1 L
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publicList findAll(finalClass entity){ (6 jr}kP
return getHibernateTemplate().find("from <tT*.nM\
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" + entity.getName()); %]>LnbM>4
} P'4oI0Bw
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publicList findByNamedQuery(finalString w(lxq:>"
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namedQuery){ D$sG1*@s-
return getHibernateTemplate R~z@voM*<
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().findByNamedQuery(namedQuery); =xO q-M
} +y+-~;5iv
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publicList findByNamedQuery(finalString query, #MZ0Sd8]&
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finalObject parameter){ m?Gb5=qo
return getHibernateTemplate qO5.NIs
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vM)?^#
().findByNamedQuery(query, parameter); 8"C;I=]8
} <lk_]+ XJ3
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publicList findByNamedQuery(finalString query, $,vZX u|Qw
C*e)UPK`
finalObject[] parameters){ 7e,EI9?.
return getHibernateTemplate UX-l`ygl
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().findByNamedQuery(query, parameters); X@,xwsM%tb
} (t.pM P4
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publicList find(finalString query){ +C~,q{u
return getHibernateTemplate().find D`r^2(WW
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(query); AJRfl% 3
} LK8K=AA3P
`jR = X
publicList find(finalString query, finalObject oa:GGW4Q
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parameter){ {5+t\~q$
return getHibernateTemplate().find 'bP-pgc
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(query, parameter); q#v&&]N=
} {nH.
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public PaginationSupport findPageByCriteria YoD1\a|
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(final DetachedCriteria detachedCriteria){ YaTJKgi"0
return findPageByCriteria LC5NB{b\%>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); w <
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} P,Fs7
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public PaginationSupport findPageByCriteria 9:^SnHAa
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(final DetachedCriteria detachedCriteria, finalint |F36^
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startIndex){ 4/S% eZB
return findPageByCriteria wU_e/+0h
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(detachedCriteria, PaginationSupport.PAGESIZE, be `\ O
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startIndex); 4oLrCQZ\
} =iy%;>I`
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public PaginationSupport findPageByCriteria +Io^U
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(final DetachedCriteria detachedCriteria, finalint xW*L^97 ;
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pageSize, ZbJzf]y:6
finalint startIndex){ wmFI?
return(PaginationSupport) #5)E4"m
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getHibernateTemplate().execute(new HibernateCallback(){ z.{T`Pn
publicObject doInHibernate My AS'Ki
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I
(Session session)throws HibernateException { G S-@drZp_
Criteria criteria = vX})6O
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detachedCriteria.getExecutableCriteria(session); &eq>>
int totalCount = v\ggFrG]
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((Integer) criteria.setProjection(Projections.rowCount hKb-l`KO
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()).uniqueResult()).intValue(); 4w0 &f
criteria.setProjection vBCQ-l<Ub
w> `3{MTQ
(null); j{EN %
List items = uWR\#D'
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criteria.setFirstResult(startIndex).setMaxResults bLoAtI
agX-V{l.
(pageSize).list(); 6/B"H#rN
PaginationSupport ps = kpi)uGvGUA
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new PaginationSupport(items, totalCount, pageSize,
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startIndex); XRVE8v+
return ps; /02|b}{
} )r-t$ L
}, true); uiDK&@RS
} 9vT@ mqKu
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public List findAllByCriteria(final U/&!F
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DetachedCriteria detachedCriteria){ &AH@|$!E
return(List) getHibernateTemplate B*E:?4(<P
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().execute(new HibernateCallback(){ /g2( <
publicObject doInHibernate |XOD~Plo^
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(Session session)throws HibernateException { j?4k{?x
Criteria criteria = W!4(EdT*Cq
;
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detachedCriteria.getExecutableCriteria(session); .r+ u pY
return criteria.list(); !'(bwbd
} a5C% OI<
}, true); m&jh7)V
} Y~( #_K
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public int getCountByCriteria(final y
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vK)^;T ;
DetachedCriteria detachedCriteria){ DSad[>Uj],
Integer count = (Integer) W4Nbl
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getHibernateTemplate().execute(new HibernateCallback(){ #p}I 84Q
publicObject doInHibernate eAS~>|N#x
x9R_KLN:;
(Session session)throws HibernateException { F,EcqM'f
Criteria criteria = M~7 gUb|
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detachedCriteria.getExecutableCriteria(session); SU9qF73Y
return ENm\1
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criteria.setProjection(Projections.rowCount 'S\YNLqQ
|H 0+.f;
()).uniqueResult(); wMNtN3
} @V:4tG.<sw
}, true); VnW]-P*:
return count.intValue(); % \Nfj)9
} 2,?4'0Z@R
} 6
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用户在web层构造查询条件detachedCriteria,和可选的 5xL%HX[S
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #jn6DL@[{
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PaginationSupport的实例ps。 vQ"EI1=7Z
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ps.getItems()得到已分页好的结果集 `J \1t
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ps.getIndexes()得到分页索引的数组 Dz;^'
ps.getTotalCount()得到总结果数 K*jV=lG
ps.getStartIndex()当前分页索引
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ps.getNextIndex()下一页索引 pB;)Hii\
ps.getPreviousIndex()上一页索引 .dwb@$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #!0le:_
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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 T(%U$ea-S
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一下代码重构了。 $ KQ7S>T
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我把原本我的做法也提供出来供大家讨论吧: [4B.;MS(
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首先,为了实现分页查询,我封装了一个Page类: +O>1Ed
java代码: &niROM,;K
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/*Created on 2005-4-14*/ )$V}tr!
package org.flyware.util.page; \
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/** ) '"@L7U
* @author Joa WzYy<
* ]etLobV
*/ v`#T)5gl-
publicclass Page { z 3)pvX5
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/** imply if the page has previous page */ f@lRa>Z(Fm
privateboolean hasPrePage; u! `oKe;
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/** imply if the page has next page */ h3Kv0^{
privateboolean hasNextPage; r!+-"hS!
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/** the number of every page */ U WYLT-^x
privateint everyPage; u|h>z|4lJj
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/** the total page number */ d4<Ic#
privateint totalPage; uV?[eiezD0
q5J6d+
/** the number of current page */ ;B>2oq
privateint currentPage; | W:JI
wjYwQ= y5
/** the begin index of the records by the current 6?OH"!b2-}
H)aeSF5
query */ w.exLC
privateint beginIndex; v{9< ATi
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/** The default constructor */ ~$} `R=
public Page(){ :{<( )gfk
W_(
} CI$pPY<u1
_q`$W9M+k
/** construct the page by everyPage c!"&E\F
* @param everyPage Rg~ ~[6G>
* */ VKRj
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public Page(int everyPage){ &z;F'>"
this.everyPage = everyPage; h7mJXS)t|
} bJ8G5QU
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/** The whole constructor */ (m|w&oA/
public Page(boolean hasPrePage, boolean hasNextPage, bj^YB,iSM
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int everyPage, int totalPage, aV`4M VWOz
int currentPage, int beginIndex){ ]v96Q/a
this.hasPrePage = hasPrePage; @4dB$QF`&
this.hasNextPage = hasNextPage; odAeBQy
this.everyPage = everyPage; ]l.y/pRP5[
this.totalPage = totalPage; :=x-b3U
this.currentPage = currentPage; = BW>jD
this.beginIndex = beginIndex; }|>mR];
} g,/gApa
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/** >en,MT|
* @return fnV^&`BB
* Returns the beginIndex. {X$8yy2zC5
*/ 16=tHo8|
publicint getBeginIndex(){ t.B%7e
return beginIndex; +Mth+qg w
} \P% E1c#
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/** pcIJija:
* @param beginIndex bf]W_I]B
* The beginIndex to set. $r} )j~c
*/ M; *f(JY$
publicvoid setBeginIndex(int beginIndex){ +BcJHNIB
this.beginIndex = beginIndex; <wV?B9j
} ]F
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/** 'ms&ty*T
* @return Dlhb'*@
* Returns the currentPage. f%ude@E3
*/ 2VaQxctk
publicint getCurrentPage(){ ;QbMVY
return currentPage; h; 105$E1
} bp Q/#\Z
a&b75.-
/** z$OKn#%T
* @param currentPage _r0[ z
* The currentPage to set. o!6gl]U'y9
*/ @MMk=/WDw
publicvoid setCurrentPage(int currentPage){ dbF?#s~u
this.currentPage = currentPage; !C>}j* 4
} ]H8,}
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/** MzLnD D^
* @return W]cJP
* Returns the everyPage. lrg3n[y-l
*/ FWpcWmS`s
publicint getEveryPage(){ m":lKXpQ
return everyPage; o>lk+Q#L @
} wc##'u
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/** $w{!}U 2+-
* @param everyPage x#z}A&
* The everyPage to set. WO{V,<;
*/ hd*bPj;
publicvoid setEveryPage(int everyPage){ Cisv**9
this.everyPage = everyPage; 8$</HNu,
} Z%_"-ENT
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/** {,z$*nf
* @return 3dm lP2
* Returns the hasNextPage. ;`<uo$R
*/ \d~sU,L;]
publicboolean getHasNextPage(){ Hbz >D5$
return hasNextPage; ^gx`@^su
} /7Z5_q_
}S84^2J_
/** zFVNb
* @param hasNextPage lt 74`9,f
* The hasNextPage to set. ()L[l@m
*/ =?fxPT[1K
publicvoid setHasNextPage(boolean hasNextPage){ r9[{0y!4
this.hasNextPage = hasNextPage; #4uuT?!
} 7!.#:+rg5#
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/** LliOhr4
* @return 5P{PBd}glp
* Returns the hasPrePage. Y]
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*/ NYopt?Xg
publicboolean getHasPrePage(){ B?d^JWTZ
return hasPrePage; R:49Gn:F
} HmxA2 ~C
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/** V2-fJ!
* @param hasPrePage _?]E)i'RI
* The hasPrePage to set. w7d(|`
*/ r9:Cq
publicvoid setHasPrePage(boolean hasPrePage){ YCJc Dab
this.hasPrePage = hasPrePage; -P"9KnsO
} Bn>"lDf,
nff
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/** 78'HE(*
* @return Returns the totalPage. w@ 1g_dy
* U/2]ACGCN^
*/ *fs'%"w-
publicint getTotalPage(){ ""-#b^DQ
return totalPage; :oRR1k
} 8^bc4(H
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/** ~dkN`1$v
* @param totalPage t+C9QXY
* The totalPage to set. 72J@Dc
*/ Y`$dtg {
publicvoid setTotalPage(int totalPage){ Vgzw ['L}
this.totalPage = totalPage; p(B>
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} Qoa gy L
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} $$my,:nH
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 L< 3U)Gp
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个PageUtil,负责对Page对象进行构造: wNzALfS
java代码: tu.Tvtudzj
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/*Created on 2005-4-14*/ t^N
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package org.flyware.util.page; a>w@9
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b
import org.apache.commons.logging.Log; uL`6}0
import org.apache.commons.logging.LogFactory; >eF4YZ"
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/** ldEZ _g^
* @author Joa C?IvXPlV
* 8=XfwwWHy<
*/ gWlv;oq
publicclass PageUtil { NI(fJ%U
879x(JII
privatestaticfinal Log logger = LogFactory.getLog O0|**Km\+
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(PageUtil.class); oSGx7dj+
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/**
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* Use the origin page to create a new page W*D]?hXU;
* @param page ED9uKp<Wbv
* @param totalRecords rgth2y]
* @return Iud]*5W
*/ 9wR-0E
)
publicstatic Page createPage(Page page, int vkFfHzR$
Ww(($e!
totalRecords){ [=Qv?am
return createPage(page.getEveryPage(), v4X\LsOP
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page.getCurrentPage(), totalRecords); .QwwGm
} <Q-Y$
^\
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/** hYm$Sx(=
* the basic page utils not including exception sY @S
ohI>\
handler V1aWVLltj
* @param everyPage TDvUiJm
* @param currentPage 41\r7
BS
* @param totalRecords z^tws*u],5
* @return page #g)$m}tv?
*/ <:v2N/i
publicstatic Page createPage(int everyPage, int [A@K)A$f
8|:bis~wm
currentPage, int totalRecords){ K|"97{*|2
everyPage = getEveryPage(everyPage); UG)XA-ez
currentPage = getCurrentPage(currentPage); a[Q\8<
int beginIndex = getBeginIndex(everyPage, MjGeH>c
["5Z=4
currentPage); .=y-T=}
int totalPage = getTotalPage(everyPage, e1*<9&S
o6{[7jI
totalRecords); SZGeF;N
boolean hasNextPage = hasNextPage(currentPage, D{b*,F:&@)
0RaE!4)!;
totalPage); -,;r %7T
boolean hasPrePage = hasPrePage(currentPage);
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|nf FI
returnnew Page(hasPrePage, hasNextPage, T#L/HD
everyPage, totalPage, ze%kP#c6!
currentPage, +9 Uo<6}
9*AH&/EXth
beginIndex); y.KFz9Qv
} nEtG(^N
"rV-D1Dki
privatestaticint getEveryPage(int everyPage){ |
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return everyPage == 0 ? 10 : everyPage; b<]--\
} Q> Lh.U,{
zF+NS]XK
privatestaticint getCurrentPage(int currentPage){ Fpz)@0K;
return currentPage == 0 ? 1 : currentPage; zli@X Z#
} bnso+cA
W(5et5DN,
privatestaticint getBeginIndex(int everyPage, int }Mh@%2$
O<A$,<6 7
currentPage){ %/b3G*$W
return(currentPage - 1) * everyPage; -pWnO9q
} (e:@7W)L
7=$@bHEF#*
privatestaticint getTotalPage(int everyPage, int x1g0_&F
);8Nj
zX1
totalRecords){ OxGS{zs
int totalPage = 0; %'}zr>tx:
hJuR,NP
if(totalRecords % everyPage == 0) s~A#B)wB
totalPage = totalRecords / everyPage; `WjRb
else = F!_ivV
totalPage = totalRecords / everyPage + 1 ; xY3KKje
pS1f y]
return totalPage; F XpI-?#E<
} 'qhi8=*
\I!C`@0
privatestaticboolean hasPrePage(int currentPage){ [M:ag_rm+f
return currentPage == 1 ? false : true; d0@&2hO
} =}bDT2Nb
H9@24NFb
privatestaticboolean hasNextPage(int currentPage, C'6yt
X(sN+7DOV
int totalPage){ ~EYsUC#B_
return currentPage == totalPage || totalPage == yuTSzl25,/
br@GnjG
0 ? false : true; \O*8%
} XI4le=^EM
*]L(,_:"
)#^5$5
} -r.Qy(}p
.7h:/d
Y:
7Ya4>*B
Ya%-/u
S;!l"1[;
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。
: h"Bf@3
C}i1)
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 0QWc1L
~1_v;LhH5+
做法如下: b7]MpL
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0j=xWC
5Op|="W.
的信息,和一个结果集List: OKXELP
java代码: ?9Lp@k~TO
M_<? <>|
T#HW{3
/*Created on 2005-6-13*/ E%A] 8y7
package com.adt.bo; {S+ $C
:A~6Gk92A
import java.util.List; ,'7 X|z/_>
-y@#
^SrJ
import org.flyware.util.page.Page; TSgfIE|
<BUKTRq
/** j %3wD2 l
* @author Joa s{"}!y=]
*/ td}%reH
publicclass Result { !Vtj:2PQL
'Gr}<B$A3
private Page page; ?h7,q*rxk
X&s@S5=r]
private List content; dX720/R
u$vA9g4
/** 4[&L<D6h
* The default constructor m%=]
j<A
*/ vpnOc2 -
public Result(){ n86=1G:%
super(); ZQY]c
} W%6Y?pf)z
nIckI!U#D
/** W7\s=t\
* The constructor using fields L0sb[:'luz
* ^ UB*Q
* @param page ZxDh94w/
* @param content t08E
2sI
*/ u3[A~V|0=
public Result(Page page, List content){ )BJ Z{E*
this.page = page; =>y%Aj&4
this.content = content; ;5ANw"Dq
} s-S#qGZ
bhqV2y*'
/** {.,-lFb\
* @return Returns the content. x{o&nhuk[S
*/ vv F:
publicList getContent(){ d=*&=r0!C{
return content; O/N
Ed)H!
} u{Rgk:bn
.%\lYk]
/** <w9<G
* @return Returns the page. ZQ MK1
*/ p+ki1!Ed
public Page getPage(){ =IIB~h[TB
return page; F\)?Ntj)>@
} `A\|qH5`W
h#e((j3-2Z
/** }$5e!t_K
* @param content 4^OPzg6Z%p
* The content to set. bvR0?xnq
*/ {&I3qk2(
public void setContent(List content){ 8c1ma
this.content = content; Ig.9:v`
} o 9?#;B$
E
U#
M.
/** hFiJHV
* @param page lk(q>dv K
* The page to set. Z%_m<Nf8T
*/ $K'A_G^
publicvoid setPage(Page page){ V1d{E 0lM
this.page = page; %F.^cd"
} I<&(Dg|XQ
} [VL+X^
5GHW~q!Zo\
FN>ns,
usFhcU
2Nau]y]=
2. 编写业务逻辑接口,并实现它(UserManager, B]_NI=d
Gc1!')g!
UserManagerImpl) MODi:jsl
java代码: ;_ TP Jy
vIK+18v7
7)FI_uW
/*Created on 2005-7-15*/ Y/Dah*
package com.adt.service; v"~0 3-SX
Y6R+i0guz
import net.sf.hibernate.HibernateException; =Felo8+
iN]#XIQ%
import org.flyware.util.page.Page; b-Uy&+:X*d
IT5a/;J
import com.adt.bo.Result; =D}]|ie
(&=gM
/** w~lxWgaY7
* @author Joa aR@s.
ll
*/ o;^k"bo6
publicinterface UserManager { wq6.:8Or-]
;q;}2
public Result listUser(Page page)throws K7jz*|2
j56Dt_
HibernateException; `yXJaTbo
| GqKa
} 0DR:qw
(vXes.|+t
y(2FaTjM
;v=v4f'+
Gd:fh5u':
java代码: B}|(/a@*
kH9fK80
h p<NVST
/*Created on 2005-7-15*/ K[G=J
package com.adt.service.impl; ~V:@4P
Xv2u7T\
import java.util.List; Lfj]Y~*z
Ic,V,#my
import net.sf.hibernate.HibernateException; w<54mGMOLr
C EMe2~
import org.flyware.util.page.Page; YS|Ve*t(L=
import org.flyware.util.page.PageUtil; -$0w-M8'
z~ R: !O-
import com.adt.bo.Result; -sqoE*K[8
import com.adt.dao.UserDAO; UwQyAD]Ht
import com.adt.exception.ObjectNotFoundException; PRpW*#"EI
import com.adt.service.UserManager; "^3pP(8;~
Pm}
/** A"PmoV?lAm
* @author Joa _=s{,t
&u
*/ /E|Ac&Qk
publicclass UserManagerImpl implements UserManager { 7Ns1b(kU
_1sjsGp>
private UserDAO userDAO; /#]4lFk:h
x*}*0).
/** omEnIfQSO
* @param userDAO The userDAO to set. 5kju{2`GF
*/ 99]&Xj
publicvoid setUserDAO(UserDAO userDAO){ 9bVPMq7}i
this.userDAO = userDAO; U$+G9
} Jd0I!L
MRn;D|Q
/* (non-Javadoc) D3MRRv#
* @see com.adt.service.UserManager#listUser }0(.HMiGj
h,u?3}Knnb
(org.flyware.util.page.Page) 8G6[\P3fQ
*/ 2TxHY|4
public Result listUser(Page page)throws dEuts*@Q
#y4+O;{
HibernateException, ObjectNotFoundException { Ki_8g
int totalRecords = userDAO.getUserCount(); cf7UV6D g
if(totalRecords == 0) hCX_^%
throw new ObjectNotFoundException <`/22S"
fZ6"DJZ
("userNotExist"); 1p%75VW
page = PageUtil.createPage(page, totalRecords); Vr1yj
List users = userDAO.getUserByPage(page); zG0191f
returnnew Result(page, users); q8_8rp-@
} <JyF5
6_#:LFke
} =iEQE
`r$c53|<u
(uk-c~T!u
&qO#EEqG]
O 6}eV^y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 2&+Nr+P
aVXk8zuL
询,接下来编写UserDAO的代码: | @Mx?(
3. UserDAO 和 UserDAOImpl: K:3u/C`
java代码: btZ9JZvMx
)rce%j7
ztRe\(9bL
/*Created on 2005-7-15*/ ),u)#`.l
G
package com.adt.dao; ]@rt/ eX
:Q@qR((&o
import java.util.List; )>X
C_ R
r`8>@2sW1
import org.flyware.util.page.Page; /eI]!a
=bwuLno>
import net.sf.hibernate.HibernateException; =OUms@xcE
n( } zq
/** wP: w8O
* @author Joa rCTH 5"
*/ l)^sE)
publicinterface UserDAO extends BaseDAO { 'Rg6JW\
"Om4P|
publicList getUserByName(String name)throws \ O#6H5F
#F~^m
HibernateException; ~g_]Sskf7
&~SPDiu.t
publicint getUserCount()throws HibernateException; *;noZ9{"+
ee+*&CT)
publicList getUserByPage(Page page)throws <PayP3E
2VgDM6h
HibernateException; s,*kWy"jp
6L)]nE0^
} `7))[._
BnL [C:|
S.#IC
lV
k m(Mv
Fz 6&.f
java代码: W_sAk~uK/
|~y>R#u8pm
9AGf4tuy
/*Created on 2005-7-15*/ CI~P3"`]
package com.adt.dao.impl; ktu{I
L,<5l?u
import java.util.List; a0]n>C`~
ox2?d<dC6
import org.flyware.util.page.Page; (i"@{[IP
WN+D}z]
import net.sf.hibernate.HibernateException; sr*3uI-)L
import net.sf.hibernate.Query; yl#(jb[?1
5^}"Tn4I
import com.adt.dao.UserDAO; ycr\vn
t
T/$6ov+K
/** Z^ e?V7q
* @author Joa %v_w"2x;
*/ n>
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public class UserDAOImpl extends BaseDAOHibernateImpl wy1xZQ<5
X4D>
implements UserDAO { 8!T6N2O6d
-b7q)%V
/* (non-Javadoc) ;Az9p h
* @see com.adt.dao.UserDAO#getUserByName j1yW{
&QoV(%:]
(java.lang.String) # RG/B2
*/ )0Lno|l
publicList getUserByName(String name)throws ^Iz(V2
V\ 7O)g
HibernateException { C]xKdPQj%
String querySentence = "FROM user in class Y@+e)p{
*&m{)cTs
com.adt.po.User WHERE user.name=:name"; '|9fDzW"]
Query query = getSession().createQuery rerl-T<3
(q@DBb4
(querySentence); )G
a%Eg9
query.setParameter("name", name); _Kw<4$0<p
return query.list(); UZ`G S$D@
} +-VkRr#
%]zaX-2dm!
/* (non-Javadoc) wTL&m+xr
* @see com.adt.dao.UserDAO#getUserCount() ZE!dg^-L
*/ )Ycjx~
publicint getUserCount()throws HibernateException { Wd R ~
int count = 0; }aPx28:/
String querySentence = "SELECT count(*) FROM FBR]) h'Z
7LQLeQvB
user in class com.adt.po.User"; Do3g^RD#
Query query = getSession().createQuery ZP]l%6\.
<ah!!
(querySentence); BaLvlB
count = ((Integer)query.iterate().next RbY=OOQ
{NS6y \,
()).intValue(); 78iu<L+If
return count; ^hpdre"
} aQzu[N
}=+J&cR
/* (non-Javadoc) ?3x7_=4t@
* @see com.adt.dao.UserDAO#getUserByPage "-pQL )f
G<S(P@ss
(org.flyware.util.page.Page) RoG
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*/ c']3N
publicList getUserByPage(Page page)throws Oc51|[
Wj
W[dK{?RB
HibernateException { y(#Aze{yC
String querySentence = "FROM user in class <vP{U
g.&n
X/
com.adt.po.User"; %LH~Im=
Query query = getSession().createQuery Spnshv8
7B|ddi7Q>
(querySentence);
OMi_')J
query.setFirstResult(page.getBeginIndex()) (4hCT*
.setMaxResults(page.getEveryPage()); W!R}eLf@
return query.list(); ,<pk&54.@'
} ]
BJ]
~w&_l57
} 8:x{
Q*W`mFul
)YP"\E
jO|D #nC
C6$F.v
至此,一个完整的分页程序完成。前台的只需要调用 aCq ) hR
.ykCmznf*
userManager.listUser(page)即可得到一个Page对象和结果集对象 vS!%!-F
7_HJ|QB
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y5 BWg
N3_rqRd^
webwork,甚至可以直接在配置文件中指定。 ]dx6E6A,
OwdA6it^f
下面给出一个webwork调用示例: B.e3IM0
java代码: ({GN.pC(
3X0"</G6
cTU%=/gbc<
/*Created on 2005-6-17*/ 4\cJ}p}LZ{
package com.adt.action.user; ~HW}Wik
f.Uvf^T}2
import java.util.List; mHm"QBa!
q0Hor
import org.apache.commons.logging.Log; D*Cn!v$
import org.apache.commons.logging.LogFactory; XM9}ax
import org.flyware.util.page.Page; W[+=_B
|>/T*zk<
import com.adt.bo.Result; *Zj2*e{Z9U
import com.adt.service.UserService; Rl. YF+YH
import com.opensymphony.xwork.Action; *A2D}X3s
(1t b
/** Gu3# y"a>
* @author Joa &YSjwRr
*/ (?G?9M#7_
publicclass ListUser implementsAction{ *8ZaG]L
e^N6h3WF
privatestaticfinal Log logger = LogFactory.getLog cgQ4 JY/6
N8]DW_bsB
(ListUser.class); }mZsK>
F5hOKUjv
private UserService userService; NrHh(:
H pZD^h?L
private Page page; MJ=(rp=YU9
]M:=\h,t>
privateList users; Sk~( t
0Gq}x;8H&
/* 'b?Px}
* (non-Javadoc) h{J=Rq
* 8Pkw'.r
* @see com.opensymphony.xwork.Action#execute() $KmhG1*s
*/ #RJFJb/
publicString execute()throwsException{ cZ<@1I5QK
Result result = userService.listUser(page); D2060ze
page = result.getPage(); 9r5<A!1#L
users = result.getContent(); l8$7N=Y
return SUCCESS; bv%A;
} #QWG5
k*?Axk#
/** ?`,Rkg0fe
* @return Returns the page. y; .U-}e1
*/ ,KfBG<3
public Page getPage(){ dbmty|d
return page; Y&G]M
} \Q
CH.~]
`8.Oc;*zu
/** mYE 8]4
* @return Returns the users. U{)|z-n
*/ BEm~o#D
publicList getUsers(){ I^CKq?V?:
return users; 0~)_/yx?S
} +&U{>?.u
|JR;E$
/** }'"4q
* @param page #dd-rooQuD
* The page to set. Ykt{]#
*/ 5S;|U&f|
publicvoid setPage(Page page){ H.n+CR
this.page = page; }Q=@$YIesD
} {<p-/|Z52
zUe)f~4
/** 9b8kRz[ c
* @param users :~%
zX*
* The users to set. }"sZ)FE
*/ M)<4|x
publicvoid setUsers(List users){ Tej&1'G
this.users = users; ^2|G0d@.:
} 0cpI2
Nydhal00
/** &3o[^_Ti
* @param userService |x
Nd^
* The userService to set. 3
zF"GT
*/ '&|]tu:q
publicvoid setUserService(UserService userService){ P ]prrKZe,
this.userService = userService; f`[gRcZ-
} AXQG
} XW^Sw;[efZ
]Uy
cT3A
kY$vPHZpN
&ND8^lR=Y;
p5`d@y\hj
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, .Lvg
$d
bsn.HT"5
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 qMA K"%x
,rO>5$ w.
么只需要: d{gj8
java代码: ^EG@tB $<
*1>zE>nlP
HgY#O
r(
<?xml version="1.0"?> :kaHvf
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <21@jdu3n,
~kkwPs2V
1.0//EN" "http://www.opensymphony.com/xwork/xwork- J4xJGO
[xrM){ItW
1.0.dtd"> UP*\p79oO
nj@l5[
<xwork> +dt b~M
!OO{qw(*g
<package name="user" extends="webwork- }'FNGn.~#
C8J3^?7E
interceptors"> >`@c9
m
tR;? o,T
<!-- The default interceptor stack name s*XwU
b')Lj]%;k
--> =,UuQJ,l
<default-interceptor-ref l5}b.B^w
Rzolue 8
name="myDefaultWebStack"/> fuwv,[m
8:iu 8c$
<action name="listUser" N@z+h
T9N&Nh7 3
class="com.adt.action.user.ListUser"> Ao%;!(\I%
<param `2j \(N,
nCj_4,O
name="page.everyPage">10</param> 6*cY[R|q!
<result @eQo
w'Cn3b)`
name="success">/user/user_list.jsp</result> 5T,In+~Kd
</action> P/'9k0zs)
!JkH$~
</package> EK-Qa<[|
W/U_:^[-
</xwork> +Y:L4`
nhUL{ER
^J([w~&
uAWmg8
gEE6O%]g
CUS^j
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 @rTAbEk{U
@\!9dK-W
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 icX$<lD
6L2Si4OGjG
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |H,g}XWMU
nt"8kv
{O"?_6',
`wyX)6A|bt
49BLJ|:P?
我写的一个用于分页的类,用了泛型了,hoho /pa8>_, ~
^w+jPT-n
java代码: R]-$]koQO
.q>4? +
m^8KHa
package com.intokr.util; wR"4slY_%
4sVr]p`
import java.util.List; dwQ*OxFl
&.\|w
/** (,J`!Y hS
* 用于分页的类<br> aWLeyXsAu
* 可以用于传递查询的结果也可以用于传送查询的参数<br> BBub'
* Qe~2'Hw#9
* @version 0.01 Qoj}]jve
* @author cheng 8Jz/'
*/ a-`OE"
public class Paginator<E> { .45XS>=z#
privateint count = 0; // 总记录数 Wgh4DhAW
privateint p = 1; // 页编号 lZ3o3"
privateint num = 20; // 每页的记录数 <z>K{:+>
privateList<E> results = null; // 结果 .?TPoqs7Z
"dKYJ&$
/** $J~~.PUXQ
* 结果总数 +Oae3VFf;
*/ >gt_C'
publicint getCount(){ XZcT-w7
return count; m-SP #?3
} "hRY+{m
[N|/d#
publicvoid setCount(int count){ I82?sQ7
this.count = count; F4m Q#YlrS
} IZm_/
dh7PpuN{
/** !U,^+"l'GP
* 本结果所在的页码,从1开始 -jZP&8dPH
* /nK)esB1L
* @return Returns the pageNo. bw@DcT&,
*/ XsldbN^6
publicint getP(){ ~IHjj1s
return p; ^J8sR4p#
} ^6?NYHMr=
(1bz.N8z
/** `.# l_-U{
* if(p<=0) p=1 3^LSK7.:
* I5"ew=x#
* @param p M y:9
*/ CqXD z
publicvoid setP(int p){ -DO*,Eecv
if(p <= 0) w"CcWng1
p = 1; ~3{C&c
this.p = p; \ B~9Ue!
} zS Yh ?NB5
K>k MKd1
/** -R!qDA"
* 每页记录数量 o W)M&$oS
*/ n'/w(o$&
publicint getNum(){ $*| :A
return num; jafq(t
} VV(>e@Bc4
9o.WJ
/** (K$K;f$"r
* if(num<1) num=1 GHHErXT\a
*/ n9;+RhxA
publicvoid setNum(int num){ UarU.~Uqi
if(num < 1) ^n@.
num = 1; p}KZ#"Q
this.num = num; U*ZP>Vv
} t)o #!)|
(/&IBd-
/** JM{S49Lx
* 获得总页数 *G^n<p$"
*/ %Fc,$ =
publicint getPageNum(){ hFw\uETu
return(count - 1) / num + 1; ,jBd3GdlZ
} H_'i.t 'SS
YJw 9 d]
/** oZ1#.o{
* 获得本页的开始编号,为 (p-1)*num+1 ;lST@>
*/ 9.|+KIRb
publicint getStart(){ d"nz/$
return(p - 1) * num + 1; j.$#10*:
} D4yJ:ATO&
7N^9D
H{`
/** e~r%8.Wm
* @return Returns the results. 5_+vjV;5
*/ -OpI,qyS
publicList<E> getResults(){ 4#uWj?u
return results; PsDks3cG
} c=l
3Sz?
(Rvke!"B
public void setResults(List<E> results){ Wh%qvV6]
this.results = results; SGW2'
} {&G7 Xa
Q5e ,[1
public String toString(){ %t0Fx
StringBuilder buff = new StringBuilder R@``MC0
?;.j)
(); Lj"~6l`)
buff.append("{"); xm>RLx}9
buff.append("count:").append(count); DCb\=E
buff.append(",p:").append(p); ze
Qgg|;
buff.append(",nump:").append(num); c,KT1me
buff.append(",results:").append [ADr
_
9`\hG%F
(results); )2}{fFa%
buff.append("}"); Nt#zr]Fz
return buff.toString(); yy4QY%
} ?7@Y=7BS4
@EzSosmF
} vy#n7hdCc
wKhuUZj{
4KE"r F