Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :rj78_e9
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 m!2Dk#t
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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 x)?\g{JH
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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 +/X'QB$R
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。 ]S:@=9JB'
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分页支持类: [yyV`&
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java代码: VsmL#@E
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package com.javaeye.common.util; P$QjDu-
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import java.util.List; 0l##M06>
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publicclass PaginationSupport { *Q>:|F[vM
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publicfinalstaticint PAGESIZE = 30; 6+FON$8
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privateint pageSize = PAGESIZE; 9?:S:Sq
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privateList items; w*
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privateint totalCount; ZX0c_Mk=
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privateint[] indexes = newint[0]; 3dbf!
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privateint startIndex = 0; gfYB|VyWo
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public PaginationSupport(List items, int /'1y`j<
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totalCount){ IBqY$K+l
setPageSize(PAGESIZE); k$c
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setTotalCount(totalCount); gctaarB&
setItems(items); Cm4*sN.&)
setStartIndex(0); A1q^E(}O
} F[u%t34'
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public PaginationSupport(List items, int V9VP"kD
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totalCount, int startIndex){ *p3P\ H^5
setPageSize(PAGESIZE); 2{CSH_"Z7
setTotalCount(totalCount); 64lEB>VNm
setItems(items); W'jXIO
setStartIndex(startIndex); ETOc4hMO
} [!le 9aNg
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public PaginationSupport(List items, int sV<4^n7
wb[(_@eZ
totalCount, int pageSize, int startIndex){ k)s 7Ev*
setPageSize(pageSize); =5`@:!t7
setTotalCount(totalCount); /)1-^ju
setItems(items); dO[4}FZ$
setStartIndex(startIndex); gp)ds^
} `VsGa
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publicList getItems(){ S:YL<_oI|
return items; j 7URg>i0
} q?L(V+X
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publicvoid setItems(List items){ ?~.&Y
this.items = items; Elp!,(+&6
} BcLt95;.\
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publicint getPageSize(){ 'EV *-_k
return pageSize; 1%"`
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} _zh5KP[{
lc-|Q#$3$
publicvoid setPageSize(int pageSize){ ?6d4T
this.pageSize = pageSize; 9C;Y5E~'L
} ?vFh)U
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publicint getTotalCount(){ f'O vG@
return totalCount; n*~
} ef&@aB
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publicvoid setTotalCount(int totalCount){ h<;[P?z
if(totalCount > 0){ ap^=CEf
this.totalCount = totalCount; Q~JKKq
int count = totalCount / 6# ";W2
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%zM
pageSize; >UY_:cW4%m
if(totalCount % pageSize > 0) 9M]"%E!s
count++; |"qB2.[
indexes = newint[count]; ~C'nBV
for(int i = 0; i < count; i++){ FH8mK)
indexes = pageSize * `uVW<z{l
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i; cl{W]4*$
} k_<{j0z.
}else{ X3{1DY3@u
this.totalCount = 0; ~[TKVjyO
} *"FLkC4
} 2?iOB6
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publicint[] getIndexes(){ zL'IN)7MU
return indexes; $af}+:'
} -!,]Y10
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publicvoid setIndexes(int[] indexes){ Lzx$"R-
this.indexes = indexes; %8CT -mQ
} \t# 9zn>
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publicint getStartIndex(){ |.O!zRm
return startIndex; h#>L:Wf5E
} i i@1!o
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publicvoid setStartIndex(int startIndex){ *}ee"eHs
if(totalCount <= 0) z-G7Y#
this.startIndex = 0; 4c[)}8\
elseif(startIndex >= totalCount) 6BU0hV
this.startIndex = indexes mqk(UOK`
&17,]# 3
[indexes.length - 1]; t"/"Ge#a
elseif(startIndex < 0) Xm:=jQn
this.startIndex = 0; iWM7,=1+
else{ ~}-p5 q2
this.startIndex = indexes uuYH6bw*d
#r.` V!=
[startIndex / pageSize]; %;(|KrUN
} _~ZQ b
} U@J/
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publicint getNextIndex(){ }&T<wm!
int nextIndex = getStartIndex() + Of7) A
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pageSize; >'-w%H/
if(nextIndex >= totalCount) ix7
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return getStartIndex(); ]9&q'7*L
else YD46Z~$
return nextIndex; _8b]o~[Z+
} ?e y&Un"
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publicint getPreviousIndex(){ `x$}~rP&)!
int previousIndex = getStartIndex() - x)VIA]
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pageSize; +yb$[E*
if(previousIndex < 0) 8#]7`o
return0; )xvx6?Ah|
else ^UvK~5tBV
return previousIndex; 9MB\z"b?A
} 6+$d
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} vN,}aV2nq
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抽象业务类 p~q_0Pg%
java代码: R8[iXXjku
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/** ECS<l*i57&
* Created on 2005-7-12 ,/?%y\:J
*/ "T{~,'T
package com.javaeye.common.business; O:,2OMB}B`
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import java.io.Serializable; Ukx/jNyYv
import java.util.List; tC?Aso
1( ?CNW[
import org.hibernate.Criteria; /;<e.
import org.hibernate.HibernateException; VX!Y`y^a
import org.hibernate.Session; *]m kyAhi
import org.hibernate.criterion.DetachedCriteria; uZ/7t(fy
import org.hibernate.criterion.Projections; N{^>MRK=5
import l|vWeBs
+f\pk \Ith
org.springframework.orm.hibernate3.HibernateCallback; (I7&8$Zl
import A&|Wvb=
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org.springframework.orm.hibernate3.support.HibernateDaoS X40la_[.
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upport; ]@/^_f>D
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import com.javaeye.common.util.PaginationSupport; EtR@sJ<
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public abstract class AbstractManager extends Jcalf{W6
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HibernateDaoSupport { MdVCD^B
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privateboolean cacheQueries = false; !bZhj3.
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privateString queryCacheRegion; vLnq%@x
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publicvoid setCacheQueries(boolean m~Y'$3w
vZ[$H
cacheQueries){ ZVdsxo<
this.cacheQueries = cacheQueries; .7pGx*WH^Y
} Q{qj
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publicvoid setQueryCacheRegion(String -7-Fd_F8
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queryCacheRegion){
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this.queryCacheRegion = ?AV&@EX2C
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queryCacheRegion; <\1}@?NGC
} r^w\9a_
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publicvoid save(finalObject entity){ Gd30Be2gd
getHibernateTemplate().save(entity); ?418*tXd
} C.yY8?|
9UeVvH
publicvoid persist(finalObject entity){ +CnyK(V
getHibernateTemplate().save(entity); |D;_:x9
} 9N~8s6Ob
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publicvoid update(finalObject entity){ E8T"{
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getHibernateTemplate().update(entity); !j!Z%]7
} )(h&Q?
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publicvoid delete(finalObject entity){ Y!++CMzU
getHibernateTemplate().delete(entity); Y<p zy8z
} F5N>Uqr*oN
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publicObject load(finalClass entity, ?%cn'=>ZI
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finalSerializable id){ jIAW-hc]
return getHibernateTemplate().load ,}9f(`
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(entity, id); [;(]Jy
} tA`mD >[
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publicObject get(finalClass entity, Cz'xGW{
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finalSerializable id){ KWFyw>*)
return getHibernateTemplate().get ftYR,!&
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(entity, id); cT/3yf
} gB(9vhj$
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publicList findAll(finalClass entity){ {E!$ xY8
return getHibernateTemplate().find("from _:wZmZU}
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" + entity.getName()); zc6Ho
} !"g=&Uy&
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publicList findByNamedQuery(finalString i Td-n9
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namedQuery){ E^b
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return getHibernateTemplate Dz[566UD
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().findByNamedQuery(namedQuery);
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} >$2E1HW.
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publicList findByNamedQuery(finalString query, X3P&"}a
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finalObject parameter){ &g*klt'B
return getHibernateTemplate |.1qy,|!X
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().findByNamedQuery(query, parameter); 0(wf{5
} uVN.=
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publicList findByNamedQuery(finalString query, @q,)fBZq
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finalObject[] parameters){ @(Z( /P;:
return getHibernateTemplate M[A-1]'
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().findByNamedQuery(query, parameters); 3"5.eZSOW
} a*V9_Px$&
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publicList find(finalString query){ T}UT7W|
return getHibernateTemplate().find T'hml
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(query); CNut{4
} Was'A+GZ
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publicList find(finalString query, finalObject DYX-5~;!
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parameter){ iDZrK%fl
return getHibernateTemplate().find <lFdexH"T
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(query, parameter); 6A}eSG3
} !&W|myN^
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ $)Wb#B
return findPageByCriteria @\ }sb]
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); G=1m]>I8
} -)X{n?i
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public PaginationSupport findPageByCriteria NW)M?f+6
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(final DetachedCriteria detachedCriteria, finalint Yr+d1(
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startIndex){ q'.;W@m
return findPageByCriteria (]OFS;%
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(detachedCriteria, PaginationSupport.PAGESIZE, "MTWjW*6
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startIndex); .?f:Nb.O
} L7m`HVCt&
@YCv
public PaginationSupport findPageByCriteria zHV|-R
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(final DetachedCriteria detachedCriteria, finalint )U'yUUi
n? ]f@O R
pageSize, !Vb,zQ
finalint startIndex){ 3EmcYC
return(PaginationSupport) D{R/#vM jk
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getHibernateTemplate().execute(new HibernateCallback(){ A';n6ne%i
publicObject doInHibernate ZY)%U*jWU
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(Session session)throws HibernateException { i *B:El1
Criteria criteria = b{BaQ>.(`
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detachedCriteria.getExecutableCriteria(session); q@%h^9.
int totalCount = ]/_G-2.R
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((Integer) criteria.setProjection(Projections.rowCount M\dO({o
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()).uniqueResult()).intValue(); )
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criteria.setProjection QNb>rLj52
|#V(p^
(null); ge$LIsE8
List items = (`pNXQ0n
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criteria.setFirstResult(startIndex).setMaxResults *2=W5LaK.
) \4
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(pageSize).list(); QF.3c6O@
PaginationSupport ps = _W |R;Cz]
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new PaginationSupport(items, totalCount, pageSize, { V0>iN:~S
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startIndex); %9X{{_
return ps; s@s/'^`
} H UkerV
}, true); 2 h<U
} y@`~ 9$
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public List findAllByCriteria(final wLUF v(&C
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DetachedCriteria detachedCriteria){ tOM(U-7Z&
return(List) getHibernateTemplate 5>P7]?U.]
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().execute(new HibernateCallback(){ |!Fk2Je,
publicObject doInHibernate ]^ #`j
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(Session session)throws HibernateException { EE]=f=3
Criteria criteria = `NSy"6{Z
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detachedCriteria.getExecutableCriteria(session); ~:EW>Fq%i
return criteria.list(); +#s;yc#=2
} f ;wc{qy
}, true); xr.XU'
} YjLe(+WQ
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public int getCountByCriteria(final B+Z13;}B
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DetachedCriteria detachedCriteria){ 4\6:\
Integer count = (Integer) q^*6C[G B
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getHibernateTemplate().execute(new HibernateCallback(){ j o_
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publicObject doInHibernate <0 uOq
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(Session session)throws HibernateException { ax_YKJ5#P
Criteria criteria = ^=0$
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detachedCriteria.getExecutableCriteria(session); C(o.Cy6
return ru{f]|
],[)uTZc
criteria.setProjection(Projections.rowCount .45^=2NGmQ
+j[`,5oS
()).uniqueResult(); ErDL^M-`
} .oR3Q/|k]
}, true); [N:BM% FQ
return count.intValue(); ^PqMi:htc
} <GF @L
} #6W,6(#^#
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用户在web层构造查询条件detachedCriteria,和可选的 I60DUuF
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 :wipE]~4t
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PaginationSupport的实例ps。 }+0z,s~0.
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ps.getItems()得到已分页好的结果集 FP@qh
ps.getIndexes()得到分页索引的数组 DZs^ 2Zc
ps.getTotalCount()得到总结果数 i8~$o:&HT
ps.getStartIndex()当前分页索引 c!Dc8=nE0m
ps.getNextIndex()下一页索引 xU}M;4kH~
ps.getPreviousIndex()上一页索引 >SDpuG&>
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 B4yh3cf
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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 EGS%C%>l/o
XP?*=Z]
一下代码重构了。 </s,pe79B
maC>LBa2/
我把原本我的做法也提供出来供大家讨论吧: U<Jt50O
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首先,为了实现分页查询,我封装了一个Page类: \[#t<dD
java代码: SRL-Z&M
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/*Created on 2005-4-14*/ _k2w(ew?
package org.flyware.util.page; >85zQ
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/** S~3\3qt$
* @author Joa mqFq_UX/T
* s[AA7>]3
*/ 1R*=.i%W
publicclass Page { 6D/ '`
o8z)nOTO;
/** imply if the page has previous page */ q`Q}yE>9
privateboolean hasPrePage; EJm4xkYLj1
E4HU 'y~
/** imply if the page has next page */ v01#>,R
privateboolean hasNextPage; Q$a
YaL]>.;Z:"
/** the number of every page */ k+1gQru{d
privateint everyPage; P`"mM?u
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/** the total page number */ {1~T]5
privateint totalPage; AyVrk
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/** the number of current page */ HI!4
privateint currentPage; OW`STp!
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/** the begin index of the records by the current WY>Knp=
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query */ T~ k)uQ
privateint beginIndex; =u|~
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/** The default constructor */ i@zY9,b
public Page(){ V3.t;.@
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} IOEM[zhb$
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/** construct the page by everyPage `fS^
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* @param everyPage n&!+wcJ;Yt
* */ SSmHEy*r)
public Page(int everyPage){ {p/YCch,
this.everyPage = everyPage; ]vo_gKZ
} A3+6#?:;
$s gH'/>
/** The whole constructor */ ,rO[mNk9@
public Page(boolean hasPrePage, boolean hasNextPage, Z[ZDQ o1
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int everyPage, int totalPage, I>"Ci(N
int currentPage, int beginIndex){ A6p`ma $L
this.hasPrePage = hasPrePage; {-WTV"L5*2
this.hasNextPage = hasNextPage; lhPGE_\
this.everyPage = everyPage; P(ZQDTbM
:
this.totalPage = totalPage; $YM_G=k
this.currentPage = currentPage; TlRk*/PlJ
this.beginIndex = beginIndex; Kf.T\V4%
} <qeCso
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/** s<7XxQ
* @return 3-x%wD.
* Returns the beginIndex. w*~Tm >U
*/ OJ,m1{9$}
publicint getBeginIndex(){ 7z'ha?
return beginIndex; Ade}g'
} 5w<A;f
!7 _\P7M
/** }[n5n
* @param beginIndex IZNOWX|Z;
* The beginIndex to set. >D_F!_
*/ &drFQ|
publicvoid setBeginIndex(int beginIndex){ LWmB,
Zf/
this.beginIndex = beginIndex; A 's-'8m
} nSS=%,?
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/** f)6))
* @return J8Z0D:5
* Returns the currentPage. D>kD1B1
*/ (tCib 4
publicint getCurrentPage(){ hbfq]v*X
return currentPage; Zb(t3I>n
} xRxy|x[
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/** ISNcswN#
* @param currentPage ^v:Z o
* The currentPage to set. aj8Rb&
*/ E zT`,#b
publicvoid setCurrentPage(int currentPage){ Ly #_?\bn
this.currentPage = currentPage; AsxD}Nw[Z*
} o8S"&O
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/**
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* @return h9CIZU[Nh
* Returns the everyPage. +^ yq;z
*/ *'8Ln tZf
publicint getEveryPage(){ VmvQvQ/9R
return everyPage; 3V;gW%>
} t;O1IMF
I/uy>*
/** 8r:M*25
* @param everyPage HEY4$Lf(I
* The everyPage to set. |>1hu1
*/ ;YH[G;aJ
publicvoid setEveryPage(int everyPage){ A lwtmDa
this.everyPage = everyPage; ?F@%S3h.
} f8n
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{IM! Wb
/** kiUk4&1
* @return 9M-K]0S(
* Returns the hasNextPage. %oof}=MxCL
*/ mP^SS
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publicboolean getHasNextPage(){ 5Ec/(-F
return hasNextPage; 5<R%H{3j
} pv# 2]v
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/** gv.6h{Ut
* @param hasNextPage g8pO
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* The hasNextPage to set. ;JTt2qQKo
*/ M$S]}
publicvoid setHasNextPage(boolean hasNextPage){ kgW @RD|
this.hasNextPage = hasNextPage; !1Y&Y@ze
} b"CAKl
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?
/** bS^WhZy'(
* @return 7$uJ7`e
* Returns the hasPrePage. )K]pnH|
*/ =/9^,
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publicboolean getHasPrePage(){ q]c5MlJXF
return hasPrePage; k$"d^*R
} LN^f1/b*
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/** {"}V&X160o
* @param hasPrePage Sycw %k
* The hasPrePage to set. m $dV<
*/ hYg'2OG
publicvoid setHasPrePage(boolean hasPrePage){ kfrY1
this.hasPrePage = hasPrePage; elO<a]hX
} W>-B [5O&[
WxUxc75
/** %dttE)oH?
* @return Returns the totalPage. cxyM\@QB3
* eN>0wd5{L
*/ B$a-og(
publicint getTotalPage(){ 8OFj0S1r`
return totalPage; \:_3i\2p
} oy\B;aAK
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/** nHst/5dA
* @param totalPage < n?=|g
* The totalPage to set. cy3Td28,
*/ q31>uF
publicvoid setTotalPage(int totalPage){ SreYJT%
this.totalPage = totalPage; c$H+g,7xQ-
} p]gT&[iJ
`!4,jd
} Akk
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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 -4 Ux,9&
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个PageUtil,负责对Page对象进行构造: AHbZQulC
java代码: mOBACTY^
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/*Created on 2005-4-14*/ b>=_*nw9
package org.flyware.util.page; zF&=U`v
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import org.apache.commons.logging.Log; WlwY <)
import org.apache.commons.logging.LogFactory; 5W? PCOh\
>FF5x#^&c
/** Lxe^v/LsT
* @author Joa ;sOsT?)7$
* w4};q%OBj
*/ 1,t)3;o$
publicclass PageUtil { /bVZ::A&_
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privatestaticfinal Log logger = LogFactory.getLog J7$_VP
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(PageUtil.class); n=sXSxl
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/** a\5FAkI
* Use the origin page to create a new page b$JBL_U5Ch
* @param page #5ax^p2*~
* @param totalRecords p~jlx~1-]
* @return &X>7n~@0
*/ ]N)DS+V/
publicstatic Page createPage(Page page, int ERMa# L
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totalRecords){ \=2m7v#E
return createPage(page.getEveryPage(), \Sy7"a
0D&> Gyc*0
page.getCurrentPage(), totalRecords); fw-\|fP
} iLX_T]1
p<GR SJIk=
/** Qyh/ed/
* the basic page utils not including exception JAb6 zpP
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handler C"V%# K
* @param everyPage
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* @param currentPage ]`o!1( GA
* @param totalRecords GHc/Zc"iX
* @return page d j5hv~
*/ d5m`Bm-{
publicstatic Page createPage(int everyPage, int %j,iAUE<
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currentPage, int totalRecords){ 7'p8a<x
everyPage = getEveryPage(everyPage); 5]Da{Wmgs
currentPage = getCurrentPage(currentPage); .IrNa>J~
int beginIndex = getBeginIndex(everyPage, 4vZ4/#(x
N3A<:%s
currentPage); LEW hb!U
int totalPage = getTotalPage(everyPage, `#s#it'y
/Ft:ffR|R
totalRecords); |i%2%V#
boolean hasNextPage = hasNextPage(currentPage, :' #\
ii|?;
totalPage); s95F#>dr
boolean hasPrePage = hasPrePage(currentPage); m?CZQq,
4mYCSu14:`
returnnew Page(hasPrePage, hasNextPage, ?8V
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everyPage, totalPage, s|yVAt|=
currentPage, [a1jCo
(c\hy53dP
beginIndex); ':h
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} Rd&9E
kyYLP"oB=
privatestaticint getEveryPage(int everyPage){ +g *k*e>l
return everyPage == 0 ? 10 : everyPage; E9fxjI%1
} Gs0H@
%/9;ZV
privatestaticint getCurrentPage(int currentPage){ R`'1t3p0i
return currentPage == 0 ? 1 : currentPage; \}*k)$r
} fC-P.:F#I
@'FE2^~Jj
privatestaticint getBeginIndex(int everyPage, int $hrIO+
cWAtju?L;
currentPage){ {=:#S+^ER
return(currentPage - 1) * everyPage; fL*T3[d
} <E,%@
r|<DqTc6l
privatestaticint getTotalPage(int everyPage, int 3\$wdUFr
2B1xUj ]
totalRecords){ yJx?M
int totalPage = 0; 48D?'lW %
>7Jr^o#|_x
if(totalRecords % everyPage == 0) EM j;2!
totalPage = totalRecords / everyPage; c@(&[/q!
else qi[Z,&
totalPage = totalRecords / everyPage + 1 ; .i"W8~<e
Qt>>$3]!!
return totalPage;
=Ufr^naA
} Bn?V9TEoO
zU5Hb2a
privatestaticboolean hasPrePage(int currentPage){ u eb-2[=
return currentPage == 1 ? false : true; CON0E~"
} )Di \_/G
L5fuM]G`
privatestaticboolean hasNextPage(int currentPage, g(x9S'H3l
Of}|ib^t
int totalPage){ yx{3J
return currentPage == totalPage || totalPage == T)~9Wac
-~f511<
0 ? false : true; ]B\H~Kn
} 4$6T+i2E
is^pgKX
b-5y9 K
} zDOKShG
\6I+K"
%b2oiKSBx?
r{?TaiK
?
zDa=7 J
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。 ! ]`
#JAL7
VaONd0Z I
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 zy'D!db`Z
&}6KPA;
做法如下: ksR1kvTm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 }YhtUWz].
DPn=n9n2
的信息,和一个结果集List: ?DV5y|}pj
java代码: >ezi3Zx^
5II(mSg8
2;3f=$3
/*Created on 2005-6-13*/ =}!Mf'
package com.adt.bo; #uCB)n&.
o(kM9G|
import java.util.List; arK_oh0B
9O.Y OiW
import org.flyware.util.page.Page; TtD@'QXq
}R4c
/** cE'L% Z
* @author Joa y3u+_KY-
*/ sW#JjtK
publicclass Result { PCrU<J 7
1j-te-}"c
private Page page; `lDut1J5n
P(k(m<0
private List content; z&8un%Jt
UO Ug 4
/** K5t0L!6<+
* The default constructor !5@_j,lW(
*/ G_H?f\/
public Result(){ VhGs/5
super(); =DbY? Q<Q
} `/&SxQB<
Z;Rp+X
/** pv!oz2w1
* The constructor using fields [%A4]QzWh
* ?(6m VyIe
* @param page U:6W+p8
* @param content 5+Mdh`
*/ MTGiAFE
public Result(Page page, List content){ b,TiMf9},h
this.page = page; }ArpPU
:]
this.content = content; V
D?*h
} ~tFqb<n
1k%k`[VC
/** S"m cUU}}
* @return Returns the content. wd@aw /
*/ 8e~|.wOL
publicList getContent(){ g?v\!/~(u
return content; ?jQ](i&
} V! |qYM.
>kZ57,
/** qB]i6*
* @return Returns the page. /.Nov
*/ ,tH5e&=U01
public Page getPage(){ /2M.~3gQ
return page; rx"s!y{!-
} RR;AJ8wd
`i
+g{kE2M
/** ,B<l
* @param content nz1'? _5
* The content to set. )+")Sz3zx
*/ OYC_;CP
public void setContent(List content){ x]mxD|?f
this.content = content; ]j~"mFAP
} y)c5u%(
^I
mP`*X
/** pg+[y<B
* @param page wu9=N
^x
* The page to set. o'<^LYSnB
*/ *1Z5+uVT[
publicvoid setPage(Page page){ y7i %W4
this.page = page; FSuAjBl0-
} ZPN
roCK`
} i|)Su4Dw
6&Juv
JPM))4YDR
L(>=BK*
g @I6$Z
2. 编写业务逻辑接口,并实现它(UserManager, 1=7jz]t
H y"x
UserManagerImpl) ,fIe&zq
java代码: M~*u;vA/
~n')&u{
IL/Yc1
/*Created on 2005-7-15*/ -F"QEL#
package com.adt.service; D'l5Zd
YKbCdLQ
import net.sf.hibernate.HibernateException; j/T>2|dA&
8n BL\{'B[
import org.flyware.util.page.Page; Ioy
I]"96'|N
import com.adt.bo.Result; Xd E`d.
gG%V 9eOQ
/** Ch()P.n?
* @author Joa t%zpNd2lk
*/ /N>e&e[35\
publicinterface UserManager { 1T_QX9
K-<^$VWh
public Result listUser(Page page)throws BG^C9*ZuP
`dMqe\o%!
HibernateException; oBq 49u1
c H-@V<
} 5m=I*.qE
MC((M,3L
bb42v7?
b?4/#&z]
M}_i52
java代码: Kz<@x`0
8By,#T".
&Lt[WT$
/*Created on 2005-7-15*/ ultG36.x
package com.adt.service.impl; 5 )2:stT73
]W0EVf=,k
import java.util.List; cWGDee(
@ ''GPL@
import net.sf.hibernate.HibernateException; (\"k&O{
6ZgU"!|r
import org.flyware.util.page.Page; cr?7O;,
import org.flyware.util.page.PageUtil; =z?%;4'|
&bqT/H18
import com.adt.bo.Result; }7G8|54t
import com.adt.dao.UserDAO; rV({4cIe9R
import com.adt.exception.ObjectNotFoundException; f\;65k_jq
import com.adt.service.UserManager; f"7M^1)h2%
p_ Fy>j
/** ]Q
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* @author Joa /MB{Pmk$R
*/ }~h'FHCC+
publicclass UserManagerImpl implements UserManager { 6~#Ih)K
PN~@
private UserDAO userDAO; S.B<pjgt
}pkj:NT
/** 3ZTE<zRQ
* @param userDAO The userDAO to set.
%dErnc$
*/ Iu~\L0R427
publicvoid setUserDAO(UserDAO userDAO){ zL5d0_E9
this.userDAO = userDAO; 8,O33qwH
} %xlqF<
v{i7h|e
/* (non-Javadoc) =.|J!x
* @see com.adt.service.UserManager#listUser OI}
&m^IOo
d0hhMx6$
(org.flyware.util.page.Page) Y
$g$x<7
*/ 9p 4"r^
public Result listUser(Page page)throws Obw?_@X
Z3;!l
HibernateException, ObjectNotFoundException { C 8#@+ Q.
int totalRecords = userDAO.getUserCount(); ~9F ,%
if(totalRecords == 0) 4E8JT#&
throw new ObjectNotFoundException Xd:7"/:r
VN4yn| f/
("userNotExist"); Fg$3N5*
page = PageUtil.createPage(page, totalRecords); o!Ev;'D
List users = userDAO.getUserByPage(page); e&ANp0|W
returnnew Result(page, users); RUCPV[{b
} (F7_S*
+ SZYg[
} 5_0(D;Q
@
P@c.*}s
B:"THN^
DlMe5=n-u
#X:
'aj98
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 D3Jr3
%>
ULc`~]
询,接下来编写UserDAO的代码: x?x`oirh
3. UserDAO 和 UserDAOImpl: M >:]lpRK
java代码: x\?;=@AW
$(s\{(Wn
J" j.'.
/*Created on 2005-7-15*/ c8)/:xxl
package com.adt.dao; |vte=)%
&"_u}I&\
import java.util.List; ""O"
`<^VR[Mx
import org.flyware.util.page.Page; K.C>
a:J
0.r4f'vk
import net.sf.hibernate.HibernateException; #8{F9w<Rf
!>x|7
/** ~mV"i7VX
* @author Joa g#NZ ,~
*/ _a_xzv'
publicinterface UserDAO extends BaseDAO { YL
jHt\
H@X oqgI
publicList getUserByName(String name)throws %I!:ITa
<
`qRA]
HibernateException; UX`]k{Mz
?6Cz[5\
publicint getUserCount()throws HibernateException; rdJm{<
H-rWDN#
publicList getUserByPage(Page page)throws ^n#1<K[E
]!:oYAm
HibernateException; s/"&9F3
&m3.h!dq
} BE&B}LfvfO
Xqp|VbDca
JXiZB
8}
8T;IZ(s
n<Svwa}
java代码: wI M{pK
{vaaFs
,~ ?'Ef80
/*Created on 2005-7-15*/ Gx?+9CV
package com.adt.dao.impl; DPe]daF
^x*nq3^h\
import java.util.List; 6
y"-I!&
nU+tM~C%a
import org.flyware.util.page.Page; g}&hl"j
k.h`Cji@
import net.sf.hibernate.HibernateException; W-RqN!snJ8
import net.sf.hibernate.Query; C7T(+Wd!,
@J[6,$UVu
import com.adt.dao.UserDAO; I3u{zHVwI
]u-SL md
/** :&}odx!-!C
* @author Joa #LcrI
*/ DG(7|`(aY
public class UserDAOImpl extends BaseDAOHibernateImpl 0uVv<Q~
W#_/ak$uF*
implements UserDAO { nGZX7Fx5
J2GcBzRH
/* (non-Javadoc) )g|
BMmB
* @see com.adt.dao.UserDAO#getUserByName Q_*_?yf
L;_c|\%
(java.lang.String) dNY"]b
*/ .=9s1~]
publicList getUserByName(String name)throws <j}lp-
0?7XtC P<
HibernateException { t^=U*~
String querySentence = "FROM user in class mIZwAKo
P`$12<\O1
com.adt.po.User WHERE user.name=:name"; JL}\*
Query query = getSession().createQuery PDx)S7+w[
fLN! EDq
(querySentence); ,Y_{L|:w
query.setParameter("name", name); C>^D*C(
return query.list(); { PlK@#UN
} (%ew604X
TGT$ >/w >
/* (non-Javadoc) @mw "W{
* @see com.adt.dao.UserDAO#getUserCount() KYJ1}5n
*/ (lA.3 4.p
publicint getUserCount()throws HibernateException { VCNT4m
int count = 0; Mro4`GL
String querySentence = "SELECT count(*) FROM gLD`wfZR
{!ZyCi19
user in class com.adt.po.User"; ^jdL@#k00
Query query = getSession().createQuery |wxGpBau
~KjJ\b)R
(querySentence); ;:&?=d
count = ((Integer)query.iterate().next VBoMT:#
~ <0Z>qr
()).intValue(); :L?_Y/K
return count; FD7H@L5
} }pNX@C#De
R)Q4
/* (non-Javadoc) 9V1cdb~?"T
* @see com.adt.dao.UserDAO#getUserByPage P=AS>N^yaL
O[~x_xeW
(org.flyware.util.page.Page) S{F-ttS"
*/ 4Tzd; P6_
publicList getUserByPage(Page page)throws 3{raKM6F
xc
1A$EY
HibernateException { +,'T=Ic{
String querySentence = "FROM user in class @
$cUNvI
`cP <}^]
com.adt.po.User"; \L!uHAE2a
Query query = getSession().createQuery `&7RMa4=
r2*<\ax
(querySentence); )9"oL!2h
query.setFirstResult(page.getBeginIndex()) :LJ7ru2
.setMaxResults(page.getEveryPage()); :bM+&EP
return query.list(); `linG1mF
} PY\PUMF>
H!r &aP
} 2F_
R/{D
?v]-^X=&
l?N`{,1^
_v5t<_^N
>X}{BDMb.
至此,一个完整的分页程序完成。前台的只需要调用 u/^|XOy
g1m-+a
userManager.listUser(page)即可得到一个Page对象和结果集对象 @_'OyRd8
Go\VfLL w
的综合体,而传入的参数page对象则可以由前台传入,如果用
Ayx^Wp*s
*3{J#Q6fk3
webwork,甚至可以直接在配置文件中指定。 =fLL|
#mc!Wt10
下面给出一个webwork调用示例: %n$^-Vc&
java代码: kN9yO5h7
,krS-.
uK*|2U6t
/*Created on 2005-6-17*/ Dk)}|GJ()"
package com.adt.action.user; =WZ%H_oxi
6k0^ x Q
import java.util.List; % +Pl+`?E
vS;'}N
import org.apache.commons.logging.Log; VC&c)X
import org.apache.commons.logging.LogFactory; ^tAO_~4
import org.flyware.util.page.Page; tiQ;#p7%
Fxd{ Zk`
import com.adt.bo.Result; zok D:c
import com.adt.service.UserService; mMw;0/n
import com.opensymphony.xwork.Action; ma8wmQ9 JR
S)\8|ym6!
/** A=3HO\n5
* @author Joa a<Uqyilm
*/ 9w^zY;Y
publicclass ListUser implementsAction{ - V) R<
ija:H'j
privatestaticfinal Log logger = LogFactory.getLog s${_K* g6
=G>(~+EA
(ListUser.class); $3
8gs{+
4 rB8Nm1
private UserService userService; ]
pPz@@xx
/)#8)"`nT
private Page page; ziL^M"~2
_vYzF+
privateList users; <)#kq1b?
%]4-{%v
/* \ElX~$fS
* (non-Javadoc) O]=C#E{
* Y(i?M~3\t
* @see com.opensymphony.xwork.Action#execute() r'aY2n^O
*/ w+UV"\!G)Q
publicString execute()throwsException{ h8}8Lp(/'
Result result = userService.listUser(page); 3B9nP._
page = result.getPage(); YB!!/ SX4
users = result.getContent(); (!zM\sF
return SUCCESS; Z!\@%`0$
} (aKZ5>>cN
`F1dyf!p<
/** oh\,OW
* @return Returns the page. w=J4zkWk
*/ T%I&txl
public Page getPage(){ RsSXhPk?
return page; W"sr$K2m|
} I6dm@{/:>
|-kEGLH[*V
/** pCt}66k}
* @return Returns the users. #)74X%4(
*/ 'DAltr<
publicList getUsers(){ 9YC&&0 C@
return users; ki4f*Ej
} B=zMYi
Q=+8/b
/** @-6?i)
* @param page hZuYdV{'h
* The page to set. -V=arm\#z
*/ M\UWWb&%\
publicvoid setPage(Page page){ "{F;M{h$},
this.page = page; 'Z[d7P
} 9*p G?3*I
3%IWGmye4
/** z\}!RBOq
* @param users zqGYOm$r
* The users to set. |=3 *;}
*/ Fk$@Yy+}e
publicvoid setUsers(List users){ Y><(?
this.users = users; D@hmO]5c
} (!n-Age
<xF?~7
/** `pYE[y+
* @param userService i QqbzOY
* The userService to set. WEC-<fN|Y\
*/ k+\7B}7F
publicvoid setUserService(UserService userService){ q3\!$IM.
this.userService = userService; I7Zq}Pxa
} 6y@<?08Q
} iEhDaC[e(b
Yq;&F0paK
MVAc8d S
OK\]*r
M(S{1|,V
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, y h-9u
>4'21,q
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 r5)f82pQ
~7BX@?
么只需要: Qa?QbHc
java代码: vs*I7<
;U7t
)/TVJAJ
<?xml version="1.0"?> AIfk"2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork w:R]!e_6\9
V'yxqI?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- h.LSMU (O
B}5XRgq
1.0.dtd"> ,CW%JIM
L&HzN{K
<xwork> j&}B<f _6J
^V,@=QL3U
<package name="user" extends="webwork- q_58Lw
3mA/Nu_
interceptors"> Ib(,P3
!L$oAqW
<!-- The default interceptor stack name =0Y'f](2eW
<w11nB)
--> ~$ WQ"~z
<default-interceptor-ref |
VRq$^g
1
'%-y
name="myDefaultWebStack"/> _^3@PM>
KqY>4tb
<action name="listUser" |Kn^w4mN
Z{16S=0
class="com.adt.action.user.ListUser"> bl9E&B/
<param G[B*TM6$
Faw. GU
name="page.everyPage">10</param> :\T_'Shq
<result /K&