Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 &>43l+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bv,_7UOG
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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 f@Mm{3&.
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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 ,y@`=
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分页支持类: os*QWSs
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java代码: 0p\R@{
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package com.javaeye.common.util;
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import java.util.List; 4SSq5Ve<
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publicclass PaginationSupport { d4<Ic#
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publicfinalstaticint PAGESIZE = 30; R06q~ >
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privateint pageSize = PAGESIZE; OO5k_J
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privateList items; 7RNf)nz
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privateint totalCount; %toxZ}OP
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privateint[] indexes = newint[0]; ?'uxYeX6
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privateint startIndex = 0;
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public PaginationSupport(List items, int :9!?${4R
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totalCount){ 6'd=% V
setPageSize(PAGESIZE); R4=n">>Q
setTotalCount(totalCount); i_T8Bfd:
setItems(items); "2:]9j
setStartIndex(0); VKRj
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} kK+<n8R2
/]4[b!OTJ
public PaginationSupport(List items, int aW$(lf2;
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totalCount, int startIndex){ NltEX14Af
setPageSize(PAGESIZE); U{n< n8
setTotalCount(totalCount); KA1Z{7UK%
setItems(items); =\H.C@r
setStartIndex(startIndex); :FOMRrf7.
} H@%Y!z@\
* bx%hX
public PaginationSupport(List items, int .lm^ +1}r
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totalCount, int pageSize, int startIndex){ biFy*+|
setPageSize(pageSize); F<y$Q0Z}
setTotalCount(totalCount); j2NnDz'
setItems(items); o =)hUr
setStartIndex(startIndex); I8
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} mf]1mG})
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publicList getItems(){ '#d`K.;_b.
return items; .r!:` 6
} WMfu5x7e4
/=co/}i
publicvoid setItems(List items){ 8d.5D&
this.items = items; Z!o&};_j
} \9*wo9cV
\A'MEd-
publicint getPageSize(){ X,d`-aKO\y
return pageSize; xFcJyjo^z
} S;[g0j
KMZ:$H
publicvoid setPageSize(int pageSize){ A9^t$Ii
this.pageSize = pageSize; bQc-ryC+.
} yZFm<_9>
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publicint getTotalCount(){ #xZ7%
return totalCount; 'ms&ty*T
} Dlhb'*@
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publicvoid setTotalCount(int totalCount){ 2VaQxctk
if(totalCount > 0){ =y.!Ny5A
this.totalCount = totalCount; y)N57#e
int count = totalCount / o#Q0J17i?
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pageSize; |~vo
if(totalCount % pageSize > 0) 1?s]nU
count++; Sgp$B:
indexes = newint[count]; ;A)w:"m
for(int i = 0; i < count; i++){ p<IMWe'tP
indexes = pageSize * Om`VQ?
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i; +$R4'{9q
} t.Hte/,k
}else{ {w*5uI%%e
this.totalCount = 0; #M$Gj>E%4
} /*=1hF
} gB1w,96J
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publicint[] getIndexes(){ ^6Y4=
return indexes; $w{!}U 2+-
} x#z}A&
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publicvoid setIndexes(int[] indexes){ }nNZp
this.indexes = indexes; Kp[ F@A#
} Ul#||B .c{
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publicint getStartIndex(){ b
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return startIndex; `BA wef
} K
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publicvoid setStartIndex(int startIndex){ T0L h"_X3
if(totalCount <= 0) JD1IL` ta;
this.startIndex = 0; 9AQMB1D*v4
elseif(startIndex >= totalCount) kc#<Gr&Z&
this.startIndex = indexes }!{9tc$<b
];X[x s
[indexes.length - 1]; F!m/n!YR
elseif(startIndex < 0) 0c*y~hUVZ
this.startIndex = 0; RzG7Xr=t
else{ Z9rmlVU6!
this.startIndex = indexes \%Wu`SlDp9
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[startIndex / pageSize]; R7YLI1ov
} (3kz(6S
} 3(D!]ku~m
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publicint getNextIndex(){ Y]
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int nextIndex = getStartIndex() + NYopt?Xg
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pageSize; R:49Gn:F
if(nextIndex >= totalCount) HmxA2 ~C
return getStartIndex(); $RA8U:Q!1e
else Nm;(M=
return nextIndex; Hrb67a%b
} LRNgpjE}
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publicint getPreviousIndex(){ *7MTq_K(An
int previousIndex = getStartIndex() - -58
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pageSize; xD[O8vQE
if(previousIndex < 0) ux-puG
return0; Kgev*xg
else 0< i]ph
return previousIndex; ^&gu{kP
} d&mSoPf
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} 9X<o8^V
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抽象业务类 tNsiokOm
java代码: 'F3cvpc`
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/** )*!"6d)^
* Created on 2005-7-12 P,.<3W"4i
*/ ? [~ "$
package com.javaeye.common.business; ?LE\pk
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import java.io.Serializable; b5r.N1ms
import java.util.List; %"#%/>U4
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import org.hibernate.Criteria; 6:Eu[PE~w
import org.hibernate.HibernateException; Aj| Gqw>
import org.hibernate.Session; e) Q{yO
import org.hibernate.criterion.DetachedCriteria; C*O648yz[
import org.hibernate.criterion.Projections; HR0t[*
import !YJfP@"e6r
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org.springframework.orm.hibernate3.HibernateCallback; 3]Jl\<0
import VXr'Z
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org.springframework.orm.hibernate3.support.HibernateDaoS =b\k$WQ_(
}6YD5?4
upport; !nX}\lw
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import com.javaeye.common.util.PaginationSupport; 'rWu}#Nb
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public abstract class AbstractManager extends ?9jl8r>
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HibernateDaoSupport { V4c$V]7
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privateboolean cacheQueries = false; )"Ef* /+
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privateString queryCacheRegion; mM*jdm(!
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publicvoid setCacheQueries(boolean R4xoc;b
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cacheQueries){ ED9uKp<Wbv
this.cacheQueries = cacheQueries; rgth2y]
} Iud]*5W
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publicvoid setQueryCacheRegion(String E:EXp7
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queryCacheRegion){ <>!Y[Xr^
this.queryCacheRegion = 8&q|*/2
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queryCacheRegion; F_KPhe$
} j2oHwt6"
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publicvoid save(finalObject entity){ m53XN
getHibernateTemplate().save(entity); HH_w!_f
} %O9kq
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publicvoid persist(finalObject entity){ CYIp 3D'k
getHibernateTemplate().save(entity); uU_0t;oR3
} l| /tKW
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publicvoid update(finalObject entity){ -68E]O
getHibernateTemplate().update(entity); xLUgbql-
} F%Te0l
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publicvoid delete(finalObject entity){ q]1HCWde
getHibernateTemplate().delete(entity); /jBjqE;_
} wI\
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publicObject load(finalClass entity, `O:ecPD4M
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finalSerializable id){ 2&L2G'
return getHibernateTemplate().load ~g&FeMo
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(entity, id); t:pgw[UJ
} os=Pr{
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publicObject get(finalClass entity, >Ln/ )j
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finalSerializable id){ [^iQE
return getHibernateTemplate().get >U.)?>G/dt
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(entity, id); Vl91I+Ev
} qu}`;\9@ld
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publicList findAll(finalClass entity){ + -[M 7J
return getHibernateTemplate().find("from $UgQ1Qc
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" + entity.getName()); RR*eq.;
} q7itznQSKc
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publicList findByNamedQuery(finalString Pfy2PpA
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namedQuery){ l4 @
return getHibernateTemplate :/F=j;o
}sbh|#
().findByNamedQuery(namedQuery); Eb9 eEa<W
} K^H{B& b8
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publicList findByNamedQuery(finalString query, _;o)MTw|'
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finalObject parameter){ QKj8~l(
return getHibernateTemplate b4l=Bg"
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().findByNamedQuery(query, parameter); D..dGh.MY
} '\vmm>
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publicList findByNamedQuery(finalString query, z_)`='&n
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finalObject[] parameters){ --(e(tvf
return getHibernateTemplate RnvPqNs
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().findByNamedQuery(query, parameters); pS1f y]
} z#$>f*b
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publicList find(finalString query){ r2KfZ>tWg"
return getHibernateTemplate().find 8T:?C~"
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(query); S4r-s;U-v/
} +<\)b(
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publicList find(finalString query, finalObject ~EYsUC#B_
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parameter){ br@GnjG
return getHibernateTemplate().find QD<GXPu?N
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(query, parameter); YQ\c0XG
} DEdJH4
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public PaginationSupport findPageByCriteria av}Giz
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(final DetachedCriteria detachedCriteria){ 15o<'4|=Lm
return findPageByCriteria v)^8e0vx
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); xWZ87
} .3yoDab
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public PaginationSupport findPageByCriteria 29W~<E8K-
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(final DetachedCriteria detachedCriteria, finalint ;y"=3-=vM"
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startIndex){ =Nyq1~
return findPageByCriteria M_<? <>|
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(detachedCriteria, PaginationSupport.PAGESIZE, ]c67zyX=%
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startIndex); ^)qOILn
} NuL.l__W
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public PaginationSupport findPageByCriteria Bl\/q83(
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(final DetachedCriteria detachedCriteria, finalint 7GY3_`
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pageSize, *B$$6'hi`
finalint startIndex){ 91|0{1
return(PaginationSupport) OA_WjTwDs
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getHibernateTemplate().execute(new HibernateCallback(){ Q+Sx5JUR~
publicObject doInHibernate vz\^Aa
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(Session session)throws HibernateException { BZ '63
Criteria criteria = 6k1;62Ntk
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detachedCriteria.getExecutableCriteria(session); 4#dS.UfI
int totalCount = (
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((Integer) criteria.setProjection(Projections.rowCount #i t)
!=-{$& {
()).uniqueResult()).intValue(); fz9
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criteria.setProjection vtm?x,h
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(null); nm8XHk]
List items = B7y^)/
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criteria.setFirstResult(startIndex).setMaxResults <WWn1k_
w=|"{-ijo
(pageSize).list(); aMLtZ7i>
PaginationSupport ps = Vr|sRvz
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new PaginationSupport(items, totalCount, pageSize, vXq2="+
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startIndex); :u
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return ps; _J N$zZ{
} !4?QR
}, true); h;+bHrKji
} acPX2B[jJ
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public List findAllByCriteria(final r+yl{
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DetachedCriteria detachedCriteria){ E1"H(m&6
return(List) getHibernateTemplate y)Y0SY1\j
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().execute(new HibernateCallback(){ =
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publicObject doInHibernate B%L dH
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(Session session)throws HibernateException { \DgWp:|
Criteria criteria = gq:2`W&5
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detachedCriteria.getExecutableCriteria(session); hFLLg|@
return criteria.list(); /:BM]K
} q]^Q?r<g::
}, true); V\2&?#GZ
} qs U ob
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public int getCountByCriteria(final <,X?+hr
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DetachedCriteria detachedCriteria){ oiKY2.yW
Integer count = (Integer) n[`KhRN
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getHibernateTemplate().execute(new HibernateCallback(){ %]KOxaf_z
publicObject doInHibernate gf]k@-)
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(Session session)throws HibernateException {
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Criteria criteria = '^6jRI,
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detachedCriteria.getExecutableCriteria(session); +{7/+Zz
return W["c3c
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criteria.setProjection(Projections.rowCount 7)FI_uW
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()).uniqueResult(); ~4}'R_
} 7hq$vI%0
}, true); xDtJ&6uFw
return count.intValue(); ej^pFo
} '|jN!y^2p
} v;_k*y[VV$
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用户在web层构造查询条件detachedCriteria,和可选的 'v42Q J"{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 =eB^(!M
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PaginationSupport的实例ps。 J;mvD^`g
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ps.getItems()得到已分页好的结果集 xBevf&tP
ps.getIndexes()得到分页索引的数组 /bBFPrW
ps.getTotalCount()得到总结果数 tAxS1<T4
ps.getStartIndex()当前分页索引 TM?RH{(r
ps.getNextIndex()下一页索引 F8T.}qI
ps.getPreviousIndex()上一页索引 4^>FN"Ve`B
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 V+y yy-/
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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 6.>l
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一下代码重构了。 q<2b,w==
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我把原本我的做法也提供出来供大家讨论吧: _go1gf7
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首先,为了实现分页查询,我封装了一个Page类: z}sBx9;
java代码: 8`4Z%;1
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/*Created on 2005-4-14*/ ex}6(;7)O
package org.flyware.util.page; ]|#%`p56
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/** O&(@Ka
* @author Joa sfuA
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* ]>%M%B
*/ XSDudL
publicclass Page { x8v2mnk
_w\A=6=q|
/** imply if the page has previous page */ a{deN9Qn
privateboolean hasPrePage; =4H"&Eu{
Hb:@]!r>
/** imply if the page has next page */ ns/L./z
privateboolean hasNextPage; {;0+N -U
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/** the number of every page */ N %K%0o-
privateint everyPage; ?--EIA8mfp
nsM :\t+
p
/** the total page number */ {WYHT6Z
privateint totalPage; z:+fiJB_
^<"^}Jh.M
/** the number of current page */ XFx p ^
privateint currentPage; re-;s
^vQ,t*Uj=
/** the begin index of the records by the current fkjo
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query */ 8F#z)>q~
privateint beginIndex; /GQN34RD
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/** The default constructor */ S7fX1y[
public Page(){ ]=EYju@
@UG%B7
} &qO#EEqG]
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/** construct the page by everyPage ^o@N.+`&<
* @param everyPage u#&ZD|
* */ HAtf/E]
public Page(int everyPage){ JPq2C\Ka
this.everyPage = everyPage; FO/[7ZH
} q(C <w
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/** The whole constructor */ o8A1cb4<T
public Page(boolean hasPrePage, boolean hasNextPage, D+u#!t[q
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int everyPage, int totalPage, Dno'-{-
int currentPage, int beginIndex){ `uN}mC!r]
this.hasPrePage = hasPrePage; #@cOyxUt
this.hasNextPage = hasNextPage; HL*Fs /W
this.everyPage = everyPage; $afE=
qC*
this.totalPage = totalPage; E/6@>.T?'
this.currentPage = currentPage; q]qKU`m!Q`
this.beginIndex = beginIndex; {|Pg]#Wi&
} \F
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/** |sIr}}
* @return f#mcWL1}
* Returns the beginIndex. u#c3T'E
*/ (>
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publicint getBeginIndex(){ MkCq$MA
return beginIndex; z|5Sy.H>
} s?g`ufF.t
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/** d>f.p"B.gj
* @param beginIndex 0kp#+&)+
* The beginIndex to set. Q-qM"8I
*/ P t)Ni
publicvoid setBeginIndex(int beginIndex){ A3#^R%2)W
this.beginIndex = beginIndex; bx5f\)
} 3r[}'ba\
H}[kit*9
/** :nPLQqXGQ
* @return r-,P
* Returns the currentPage. |~Op|gs
*/ 0';U3:=i,
publicint getCurrentPage(){ I5$@1+B
return currentPage; >n^| eAH
} ;Ww s;.~
F.%g_Xvk:
/** =%\y E0#
* @param currentPage !4blX'<w
* The currentPage to set. i3s,C;7[2
*/ uoIvFcb^
publicvoid setCurrentPage(int currentPage){ D_W,Jmet
this.currentPage = currentPage; o_K.
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} Z|h&Zd1z
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/** e9 `n@
* @return Uo7V)I;o
* Returns the everyPage. h ?Ni5
*/ 3,QsB<9Is
publicint getEveryPage(){ 9\aR{e,1
return everyPage; QS*!3?%
} O6[, K1,
xMb)4 cw}
/** FuKp`T-H
* @param everyPage 9~En;e
* The everyPage to set. !}TZmwf'
*/ jYv`kt
publicvoid setEveryPage(int everyPage){ 7a4b,-93
this.everyPage = everyPage; aIA9rn
} Eed5sm$H
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/** PZDj)x_%B&
* @return S5W*,?
* Returns the hasNextPage. /;[Zw8K7
*/ 7E-1
#4
publicboolean getHasNextPage(){ S\F;b{S1
return hasNextPage; )G
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} _Kw<4$0<p
B}(+\Q$I
/** [YsN c
* @param hasNextPage 2[ #7YWs
* The hasNextPage to set. CXZO
*/ |?tUUT!`t
publicvoid setHasNextPage(boolean hasNextPage){ 2GHmA_7P
this.hasNextPage = hasNextPage; '}Tf9L%
} POl[]ni=>
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/** "K7{y4
* @return 4]VoIUIuN
* Returns the hasPrePage. mo$`a6[h<
*/ |BO!q9633V
publicboolean getHasPrePage(){ RbY=OOQ
return hasPrePage; xw)$).yc
} ex-0@
bw@"MF{
/** [xTu29X.
* @param hasPrePage mihR
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* The hasPrePage to set. |#6B<'e'
*/ >A+0"5+_p
publicvoid setHasPrePage(boolean hasPrePage){ U|Du9_0
this.hasPrePage = hasPrePage; S:*.,zC
} AWY#t&
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/** [+q':T1W-
* @return Returns the totalPage. >AbgJ*X.
* @Yv.HhO9
*/ 7({"dW
publicint getTotalPage(){ ;{zgp
return totalPage; Spnshv8
} Nan@SuKY
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/** 7V^\fh5~
* @param totalPage E&}@P0^
* The totalPage to set. VS W:h
*/ UX?EOrfJ
publicvoid setTotalPage(int totalPage){ Jj_ t0"
this.totalPage = totalPage; O,&nCxB]
} H\zV/1~Y
.%.bIT
} ?8g*"&cn
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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 yc#0c[ZQu
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个PageUtil,负责对Page对象进行构造: X0h`g)Bbf
java代码: th$?#4SbR
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Z'vic#
/*Created on 2005-4-14*/ O> 5xFz'm
package org.flyware.util.page; PD-<D~7
tSP)'N<
import org.apache.commons.logging.Log; n#{z"G
import org.apache.commons.logging.LogFactory; 4\cJ}p}LZ{
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/** f.Uvf^T}2
* @author Joa mHm"QBa!
* &2~c,] 9C
*/ O?6ph4'
publicclass PageUtil { 8"f Z>XQ
b6@(UneVM
privatestaticfinal Log logger = LogFactory.getLog Zj(2$9IU
|;G9K`8
(PageUtil.class); rF/k$_bFt
#s 4v0auK
/** /$q9
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* Use the origin page to create a new page (}]ae*
* @param page :y>$N(.8f
* @param totalRecords d]89DdZk
* @return )_m#|U?Rex
*/ [>rX/a%c
publicstatic Page createPage(Page page, int x&n gCB@O
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totalRecords){ +"u6+[E
return createPage(page.getEveryPage(), aBBTcN%'
}mZsK>
page.getCurrentPage(), totalRecords); F5hOKUjv
} NrHh(:
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/** gc
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* the basic page utils not including exception _iJ8*v8A
jD`p;#~8
handler 9S.J%*F7
* @param everyPage ;tBc&LJ?
* @param currentPage Lrr1) h
* @param totalRecords {^Y0kvnd
* @return page *!~jHy8F
*/ O&]P
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publicstatic Page createPage(int everyPage, int #RJFJb/
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currentPage, int totalRecords){ ceW,A`J
everyPage = getEveryPage(everyPage); F2B9Q_>P
currentPage = getCurrentPage(currentPage); w7(jSPB
int beginIndex = getBeginIndex(everyPage, 1x"S^j
I6q]bQ="
currentPage); jm~qD
T,
int totalPage = getTotalPage(everyPage, S)$)AN<O
LW"p/`#<
totalRecords); )kBN]>&R
boolean hasNextPage = hasNextPage(currentPage, #o(c=
1 2Lc$\3P
totalPage); MPexc5_
boolean hasPrePage = hasPrePage(currentPage); m(CbMu
6 4fB$
returnnew Page(hasPrePage, hasNextPage, =;) M+"
everyPage, totalPage, w2o%{n\L
currentPage, <0P7NC:Ci
wDL dmrB
beginIndex); <9BM%
} jt*VD>ji
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privatestaticint getEveryPage(int everyPage){ J:N4F.o&K
return everyPage == 0 ? 10 : everyPage; 0~)_/yx?S
} +&U{>?.u
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privatestaticint getCurrentPage(int currentPage){ 2tEA8F~k
return currentPage == 0 ? 1 : currentPage; ^:(:P9h
} b<1k$0J6
nB8JdM2h{
privatestaticint getBeginIndex(int everyPage, int -F]0Py8(
FL,av>mV
currentPage){ 5bfd8C
return(currentPage - 1) * everyPage; uB`H9
} wva| TZ
5ree3 quh
privatestaticint getTotalPage(int everyPage, int T!iRg=<bz
cNd;qO0$
totalRecords){ 4X()D {uR
int totalPage = 0; %Ob#GA+
MPn
6sf9M
if(totalRecords % everyPage == 0) $69ef[b
totalPage = totalRecords / everyPage; |?kZfr&9q
else [pc6!qhDG&
totalPage = totalRecords / everyPage + 1 ; W@T_-pTCjK
ThvVLK
return totalPage; e%B;8)7
} ~&UfnO
tW=,o&C=
privatestaticboolean hasPrePage(int currentPage){ +Vf39}8
return currentPage == 1 ? false : true; _:0)uR LS
} aCwb[7N
0zL7$Q#c
privatestaticboolean hasNextPage(int currentPage, ",pN.<F9O
ql+tqgo
int totalPage){ +1R
qo
return currentPage == totalPage || totalPage == ;)SWUXa;{
LK?V`J5wY
0 ? false : true; x'uxSeH$
} M.[A%_|P
r
N.<S[
PXH"%vVF
} MV~-']2u
^EG@tB $<
7p!w(N?s
I1TzPe
=`
%iv|>r0
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。 _F"o0K!u
'u%;5;%2
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 <f')]
]t23qA@^2
做法如下: 2&k5X-Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~I_v {
_i-(`5
的信息,和一个结果集List: IIrXI8'}
java代码: Z6`oGFq
n*HRGJ
.QaHE`e{
/*Created on 2005-6-13*/ gk*Md+
package com.adt.bo; 6?CBa]QG
=LsW\.T6
import java.util.List; 9AbSt&#
M[Kk43;QY!
import org.flyware.util.page.Page; $;ssW"7~Qn
z;74(5?q
/** I|{A&G}|q
* @author Joa ZRjqjx
*/ 3=SN;cn
publicclass Result { D+y_&+&,t
fuwv,[m
private Page page; 8:iu 8c$
N@z+h
private List content; EJbFo682
,IODV`L
/** IO(Y_7
* The default constructor RyxEZ7dC<y
*/ ~MgU"P>
public Result(){ 0(
s
io\
super(); dV5a Ij
} 1e0O-aT#Q
=36e&z-#
/** 0UHX Li47Y
* The constructor using fields B;r o(R
* $?dAO}f3O)
* @param page 5:=ECtKi
* @param content sbZ^BFqp
*/ @_O,0d
g
public Result(Page page, List content){ XyS|7#o
this.page = page; _QhB0/C
this.content = content; xEA%UFB.!G
} ]{[8$|Mg
X1P_IB
/** (IrX\Y
* @return Returns the content. e>ZF? (a0
*/ h,D6MP
publicList getContent(){ E2PMcT{)_
return content; rQ4i %.
} 49BLJ|:P?
/pa8>_, ~
/** ^w+jPT-n
* @return Returns the page. R]-$]koQO
*/ .Fz5K&E=
public Page getPage(){ f
+#
return page; K }]0<\N
} zW@OSKq4
6Wos6_
/** \n@S.Y?P
* @param content K-xmLEu
* The content to set. e|L$e0
*/ X@ljZ
public void setContent(List content){ CQq'x+{F
this.content = content; =uYz4IDB
} 4-?'gN_
A5lP%&tu(
/** xTnd9'Pk`:
* @param page `f@VX
:aL}
* The page to set. l*+"0
*/ <Wn"_Ud=
publicvoid setPage(Page page){ F^],p|4f
this.page = page; CKAs3",
} rQncW~
} S+i .@N.^
pvz*(u
yrDWIU(8;6
-V'`;zE6
m-SP #?3
2. 编写业务逻辑接口,并实现它(UserManager, I92c!`{
=,aWO7Pz
UserManagerImpl) a?+Ni|+
java代码: !f(aWrw7e6
S;o U'KOY
IZm_/
/*Created on 2005-7-15*/ iw Hy!Vi-5
package com.adt.service; s$ONht
/12D >OK
import net.sf.hibernate.HibernateException; ^ExA
=jik33QV<
import org.flyware.util.page.Page; q4k)E
]~,V(K
import com.adt.bo.Result; L"i
B'=
dBV^Khf J
/** x 5u.D^
* @author Joa cx]O#b6B.
*/ ZKGS?z
publicinterface UserManager { Tl#Jf3XY}
XFeeNcqF
public Result listUser(Page page)throws M y:9
CS 7"mE`{
HibernateException; s*g yk
Dm@wTt8N(
} XUD/\MoV
ub"(,k P
s$Il;
3:$hC8
TA47lz q
java代码: 7'[C+/:
tQ7DdVdix
gTK5z.]
/*Created on 2005-7-15*/ hT&,5zaWdv
package com.adt.service.impl; {&Kq/sRz
5zlgmCGow
import java.util.List; (K$K;f$"r
GHHErXT\a
import net.sf.hibernate.HibernateException; \C3ir &
Fj9/@pe1
import org.flyware.util.page.Page; \/jr0):
import org.flyware.util.page.PageUtil; fhu-YYJt
qO
import com.adt.bo.Result; ]P TTI\n
import com.adt.dao.UserDAO; *G^n<p$"
import com.adt.exception.ObjectNotFoundException; ^4LkKYMS
import com.adt.service.UserManager; F|*{Ma
d{.cIv
/** a;Ic!:L
* @author Joa {~yj]+Im
*/ H/_R!G8\
publicclass UserManagerImpl implements UserManager { r}i<cyL
"C$z)
private UserDAO userDAO; 4C(v BKl
j.$#10*:
/** lz!F{mR
* @param userDAO The userDAO to set. O)MKEMuA
*/ ^R.#n[-r2
publicvoid setUserDAO(UserDAO userDAO){ 9&A-o
this.userDAO = userDAO; %zH NX4
}
6h
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'sJ=h0d_[V
/* (non-Javadoc) P>=~\v nN#
* @see com.adt.service.UserManager#listUser n4%|F'ma
y
D.S"
(org.flyware.util.page.Page) Q5e ,[1
*/ %t0Fx
public Result listUser(Page page)throws R@``MC0
buo_H@@p{s
HibernateException, ObjectNotFoundException { rt%.IQdY
int totalRecords = userDAO.getUserCount(); *b?C%a9
if(totalRecords == 0) :X[(ymWNE
throw new ObjectNotFoundException KQ3]'2q
FxSBxz<N-A
("userNotExist"); (Q !4\Gy
page = PageUtil.createPage(page, totalRecords); <@n/[ +3
List users = userDAO.getUserByPage(page); Q3#-q>;7
returnnew Result(page, users); lTPo2-j/eK
} 88}c+V+N!
o#{D;'
} KO(+%>^R
XM3N>OR.
@.fuR#
"G P!]3t
irCS}Dbw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 euM7>
$`
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询,接下来编写UserDAO的代码: lhTjG,U=
3. UserDAO 和 UserDAOImpl: )W'l^R4W
java代码: F\+wM*:U
H,qIHQW#
hGcq>Cvf
/*Created on 2005-7-15*/ #d%'BUde
package com.adt.dao; fGJPZe
k
oo`JHC
import java.util.List; SF 61rm
.ag4i;hS8
import org.flyware.util.page.Page; i 8I%}8
In|:6YDL&
import net.sf.hibernate.HibernateException; ~#iRh6^98
KzZ!
CB\
/** >2`)S{pBD
* @author Joa C>Qgd9
*/ ^.,pq?_
publicinterface UserDAO extends BaseDAO { ilQR@yp*
,#&lNQ'I
publicList getUserByName(String name)throws \`o+Le+%
o=?sM q1<
HibernateException; OA2<jrGB!
} ab@Nd$
publicint getUserCount()throws HibernateException; PygT_-3z{
$78fR8|r-
publicList getUserByPage(Page page)throws m/n_e g
!!_K|}QOE
HibernateException; A!s\; C
sM({u/
} 0\%/:2
A] pLq`
aT[Z#Zd, N
}pj>BK>
?"PUw3V3lB
java代码: `@ULG>
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ylz;
?hvPPEJf
/*Created on 2005-7-15*/ j$^3
package com.adt.dao.impl; EtJyI&7VK
i;c0X+[
import java.util.List; D61CO-E(D
y%k\=:m
import org.flyware.util.page.Page; = ^:TW%O
/ZZo`
import net.sf.hibernate.HibernateException; OBi9aFoQ
import net.sf.hibernate.Query; _)Q)tOW
(=0W[@k
import com.adt.dao.UserDAO; 2}>jq8Y47
^ruS
/** ~YOwg\w^
* @author Joa ;!&A
*/ B#AAG*Ai8
public class UserDAOImpl extends BaseDAOHibernateImpl |r 1\
rOw""mE
implements UserDAO { :y%%Vx~
(;P)oB"`C
/* (non-Javadoc) zx'G0Z9]
* @see com.adt.dao.UserDAO#getUserByName .MMFN}1O
64>E|w
(java.lang.String) jDIO,XuF
*/ [Rw0']i`4
publicList getUserByName(String name)throws Ek(.
["
:\L{S
HibernateException { VdQ}G!d
String querySentence = "FROM user in class +4f>njARIb
Bvzl*
&?
com.adt.po.User WHERE user.name=:name"; q$e2x=?
Query query = getSession().createQuery LU~U>
u _s
(querySentence); 6ND,4'6
query.setParameter("name", name); Zalgg/.
return query.list(); -}1S6dzr
} ;$l!mv7
XP
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/* (non-Javadoc) Q^/66"Z:Z
* @see com.adt.dao.UserDAO#getUserCount() T[B@7$Dp*
*/ aiGT!2
publicint getUserCount()throws HibernateException { w|gtb~oh
int count = 0; AJ[g~s't
String querySentence = "SELECT count(*) FROM ~"!F&
9+U%k(9
user in class com.adt.po.User"; RK#e7
Query query = getSession().createQuery GrjL9+|x
|;ycEB1
(querySentence); _H>ABo
count = ((Integer)query.iterate().next Q*Per;%J
@FIR9XJ
()).intValue(); Bx0^?>
return count; xz[a3In+
} Um]>B`."wK
&e@2zfl7
/* (non-Javadoc) bVSa}&*kM
* @see com.adt.dao.UserDAO#getUserByPage x0@J~
_0
(p26TN;*$5
(org.flyware.util.page.Page) +Tc<|-qQn
*/ OsPx-|f
S~
publicList getUserByPage(Page page)throws zI8Q "b
e5maZ(.;F
HibernateException { n
c:^)G
String querySentence = "FROM user in class 'W usEME
sh[Yu
com.adt.po.User"; 7g}4gX's
Query query = getSession().createQuery FYR%>Em
%5 0}oD@
(querySentence); P}N%**>`
query.setFirstResult(page.getBeginIndex()) a{^[<
.setMaxResults(page.getEveryPage()); >
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return query.list(); 9"1 0:\U
} eG9tn{
KL,=Z&.<=
} dN\Byl(6
P;bl+a'gu
4_3Jpz*
v>YdPQky
^%-$8sV
至此,一个完整的分页程序完成。前台的只需要调用 DhV($&*M
su/l'p'
userManager.listUser(page)即可得到一个Page对象和结果集对象 )Y}t~ Zfx
SLpB$puS
的综合体,而传入的参数page对象则可以由前台传入,如果用 $r *7)/
LOpnPH`
webwork,甚至可以直接在配置文件中指定。 qEPvV
&0SX*KyI
下面给出一个webwork调用示例: A#M#JI-Y
java代码: dX{|-;6vm
N~_GJw@
zvYkWaa_Qz
/*Created on 2005-6-17*/ xu(5U`K
package com.adt.action.user; A-1Wn^,>*
$UavM|
import java.util.List; 9KRHo%m
f305 yo
import org.apache.commons.logging.Log; u$$@Hw
import org.apache.commons.logging.LogFactory; evNo(U\C
import org.flyware.util.page.Page; 3Ba>a(E
v+f:VA
import com.adt.bo.Result; a'U7 t
import com.adt.service.UserService; I-oI,c%+
import com.opensymphony.xwork.Action; >(S4h}^I
uQazUFw
/** (f^WC,
* @author Joa 2s>dlz
*/ f9u ^/QVS&
publicclass ListUser implementsAction{ -v.\CtpHv
_}R?&yO
privatestaticfinal Log logger = LogFactory.getLog U*`7
(g
xCP3
(ListUser.class); I1yZ7QY
LvgNdVJDP|
private UserService userService; [>QV^2'Z
W&ya_iP~C
private Page page; !c[(#g
L&ySXc=
privateList users; >B/ jTn5=
5n!
V^ !
/* 3US}('
* (non-Javadoc) S%<RV6{aiM
* \.y|=Ql_u
* @see com.opensymphony.xwork.Action#execute() IJ2 ]2FI
*/ {%5k1,/(
publicString execute()throwsException{ jm0J)Z_"nr
Result result = userService.listUser(page); *#-X0}'s
page = result.getPage(); DKgwi'R
users = result.getContent(); BlUl5mP}>
return SUCCESS; m6tbN/EJZ
} By(:%=.
a5ZU"6Hi
/** {2G9>'
* @return Returns the page. Yh)yp?
*/ S/G6NBnbS
public Page getPage(){ 4zs1BiMG
return page; ,}2yxo;i
} H$TYp
0KO_bF#EB=
/** [T#5$J
* @return Returns the users. La9v97H:
*/ 8aZuI|z
publicList getUsers(){ *t J+!1
return users; __r]@hY
} |&B.YLx
\9;u.&$mNB
/** jjbBv~vs
* @param page <jE6ye(R
* The page to set. Ab`mID:
*/ P/snzm|@
publicvoid setPage(Page page){ ^N}zePy0
this.page = page; ?;@xAj
} s''?:
+
h1@|UxaE#
/** }[XzM/t
* @param users g\;AU2?p7
* The users to set. 3kFSu
*/ w^MU$ubx
publicvoid setUsers(List users){ }MAQhXI^O|
this.users = users; ufAp7m@ud
} B5h-JON]-
^(y=DJ7
/** wJ@8-H 8}
* @param userService q(<#7spz
* The userService to set. <ABN/nH
*/ RB<LZHZI
publicvoid setUserService(UserService userService){ | n5F_RL
this.userService = userService; )w];eF0c
} ''Fy]CwH(
} UH/) 4Wg
#R$d6N[H
k%-_z}:3V
TJFxo?
gC"
_h>S7-X
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, R r! PU
uU(G &:@
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 6OR5zXpk
S6-)N(3|
么只需要: s\QhCS
java代码: RK?b/9y
P\\4 w)C
2`>/y
<?xml version="1.0"?> hNBv|&D#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <![tn#_
nM:e<`r
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <"w;:Zs
V\^rs41$;
1.0.dtd"> /.<%y8v
D>M
a3g
<xwork> e^kccz2f
4DI.RK9
<package name="user" extends="webwork- RG/M-
<,p|3p3
interceptors"> *O-1zIlp
bOjvrg;Sz\
<!-- The default interceptor stack name Poy ]5:.
fP>_P#gZ
--> 0VC8'6S_k
<default-interceptor-ref .,zrr&Po
yoa"21E$
name="myDefaultWebStack"/> xLX<