Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 kG*~|ma
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +ck}l2
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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 i}?>g -(
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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 /a o5FL
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分页支持类: Z/J y'$x
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java代码: T[A69O]v
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package com.javaeye.common.util; ?z
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import java.util.List; E4xa[iZ
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publicclass PaginationSupport { LreP4dRe
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publicfinalstaticint PAGESIZE = 30; lw5`p,`
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privateint pageSize = PAGESIZE; PFK
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privateList items; ;*&-C9b
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privateint totalCount; ete.!*=
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privateint[] indexes = newint[0]; Sa5G.^XI
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privateint startIndex = 0; `@s^(hc7i
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public PaginationSupport(List items, int 5/z/>D;
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totalCount){ {1
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setPageSize(PAGESIZE); 0qT%!ku&
setTotalCount(totalCount); ?G&ikxl
setItems(items); c[Zje7 @
setStartIndex(0); Z EO WO
} Om {'1
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public PaginationSupport(List items, int y* h<MQ
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totalCount, int startIndex){ {FTqu.
setPageSize(PAGESIZE); @xZR9Z8]L
setTotalCount(totalCount); WOf 4o
setItems(items); 4v|W-h"K
setStartIndex(startIndex); u>/ TE
} 61
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public PaginationSupport(List items, int BL58] P84
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totalCount, int pageSize, int startIndex){ $u6
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setPageSize(pageSize); H 7
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setTotalCount(totalCount); ~< x:q6
setItems(items); y18Y:)DkL
setStartIndex(startIndex); 6\S~P/PkE
} Pr,q*_Yy
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publicList getItems(){ /,Jqmm#s^
return items; 3DG_QVg^v
} .w,q0<}
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publicvoid setItems(List items){ 9Lfv^V0
this.items = items; 5nVt[Puw
} /vb`H>P
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publicint getPageSize(){ mlS$>O_aX
return pageSize; pFz`}?c0
} !$>R j
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publicvoid setPageSize(int pageSize){ eKqk= (
this.pageSize = pageSize; $xdy&
} eQvg7aO;
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publicint getTotalCount(){ [;sRV<
return totalCount; Y:)e(c"A
} -`TEVS?`l
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publicvoid setTotalCount(int totalCount){ W'u>#
if(totalCount > 0){ mUx+Y ]Ep
this.totalCount = totalCount; ps DetP
int count = totalCount / SOvF[,+
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pageSize; {P#|zp 4C{
if(totalCount % pageSize > 0) %BB%pC
count++; s=/v';5J2!
indexes = newint[count]; 6/dI6C!
for(int i = 0; i < count; i++){ QoH6
indexes = pageSize * PRE|+=w$
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i; %3''}Y5
} #@nezu2
}else{ LvYB7<zk>
this.totalCount = 0; _``=cc
} "i W"NFO
} t}tEvh
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publicint[] getIndexes(){ x`)&J
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return indexes; EI^C{$Y
} 3>VL}Ui}
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publicvoid setIndexes(int[] indexes){ *%@h(js
this.indexes = indexes; =+d?x56
} 2*#|Nj=^
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publicint getStartIndex(){ gEE\y{y
return startIndex; Qv/=&_6
} *<ewS8f*6
*$ %a:q1U
publicvoid setStartIndex(int startIndex){ UN<]N76!
if(totalCount <= 0) Gjo`
this.startIndex = 0; u!qP
elseif(startIndex >= totalCount) h>OfOx/{q9
this.startIndex = indexes 85xR2 <:
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[indexes.length - 1]; {%6`!WW[
elseif(startIndex < 0) Ck7uJI<x
this.startIndex = 0; pBA7,z"`mP
else{ I"7u2"@-8j
this.startIndex = indexes "C0Q(dr/n
b(O3@Q6[
[startIndex / pageSize]; y:qUn!3
} 7o5BXF
} V[vl!XM
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publicint getNextIndex(){ oIj#>1~c%
int nextIndex = getStartIndex() + N7R!C)!IL
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pageSize; i5,kd~%O
if(nextIndex >= totalCount) y>e.~5;
return getStartIndex(); _[ZO p ~
else 3HY9\'t6
return nextIndex; !5uGd`^I
} $43qME
l$bu%SZ
publicint getPreviousIndex(){ Z^MNf
int previousIndex = getStartIndex() - !^Y(^RS@
=h73s0]
pageSize; F;0}x;:>
if(previousIndex < 0) s>n)B^64W
return0; Ng>h"H
else dQR-H7U
return previousIndex; Qhcu>ra
} ?]Xpi3k
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} =xx]@
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抽象业务类 L"*/:$EJL.
java代码: mZ"4&U
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/** 0$fpIz
* Created on 2005-7-12 N `F~n%N
*/ 7 X'u6$i
package com.javaeye.common.business; XaPV94
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import java.io.Serializable; l u%}h7ng
import java.util.List; 9kS^Abtk
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import org.hibernate.Criteria; Cg?&wj<
import org.hibernate.HibernateException; t$#jL5
import org.hibernate.Session; RcU}}V
import org.hibernate.criterion.DetachedCriteria; ' x35=@
import org.hibernate.criterion.Projections; !s?nJ(p
import I(7NQ8Hx
Hm'=aff6A
org.springframework.orm.hibernate3.HibernateCallback; \WB<86+z
import !AfHk|
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org.springframework.orm.hibernate3.support.HibernateDaoS Opc
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upport; .j<]mUY
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import com.javaeye.common.util.PaginationSupport; 0Bi.6r
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public abstract class AbstractManager extends OL,TFLn4
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HibernateDaoSupport { |My4SoOF
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privateboolean cacheQueries = false; !SdSE^lz`
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privateString queryCacheRegion; e-#BDN(O
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publicvoid setCacheQueries(boolean E`de7
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cacheQueries){ =Bhe'.]QSx
this.cacheQueries = cacheQueries; fd<:_f]v
} qUGC"<W
};jN\x?&q
publicvoid setQueryCacheRegion(String (VEpVn3{
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queryCacheRegion){ ah0`KxO]
this.queryCacheRegion = #
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queryCacheRegion; /-+xQn]
} ]cZ!y
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publicvoid save(finalObject entity){ 5aZ2j26
getHibernateTemplate().save(entity); Xi,CV[L\
} ^c4@(]v'G
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publicvoid persist(finalObject entity){ BB*f4z$Y%
getHibernateTemplate().save(entity); ~8P!XAU56%
} 4;]hK!AXS
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publicvoid update(finalObject entity){ mmEYup(l0;
getHibernateTemplate().update(entity); Cdu4U}^H
} Za3]d+qm
Zrk4*/
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publicvoid delete(finalObject entity){ v}O30wE
getHibernateTemplate().delete(entity); 'o+L41
} ^l=!JP=M=
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publicObject load(finalClass entity, -$jEfi4I
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finalSerializable id){ fW3(&@
return getHibernateTemplate().load I]<_rN8~ o
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(entity, id); (#Gw1
} MLje4
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publicObject get(finalClass entity, rrqR}}l
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finalSerializable id){ dx&'fe*?
return getHibernateTemplate().get `YLD`(\
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(entity, id); f~y%%+{p
} ?:8ido#-
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publicList findAll(finalClass entity){ m)v"3ib
return getHibernateTemplate().find("from UA8GL D9
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" + entity.getName()); gL[yA?GoM
} !GLz)#SBl
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publicList findByNamedQuery(finalString +HeTtFo{M
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namedQuery){ Gh}LlX!w
return getHibernateTemplate Y*>#T
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().findByNamedQuery(namedQuery); bRJMYs
}
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publicList findByNamedQuery(finalString query, }Q?c"H!/
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finalObject parameter){ %?uc><&?e
return getHibernateTemplate ;WM"cJo9
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().findByNamedQuery(query, parameter); cU@SIJ)
} [}/LD3
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publicList findByNamedQuery(finalString query, UXugRk%d
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finalObject[] parameters){ ?ROqn6k&c
return getHibernateTemplate i;jw\ed
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().findByNamedQuery(query, parameters); 9:,\gw>F
} |e?64%l5P
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publicList find(finalString query){ g[Ib,la_a
return getHibernateTemplate().find ang~<
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(query); /X(t1 +
} 8X`tU<Ab
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publicList find(finalString query, finalObject e7(ucE
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parameter){ ? glSC$b
return getHibernateTemplate().find J(%0z:exs
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(query, parameter); m&\h4$[kql
} l>{R`BZ/
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public PaginationSupport findPageByCriteria {Jx4xpvPo
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(final DetachedCriteria detachedCriteria){ ("+}=*?OF3
return findPageByCriteria kc @[9eV
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q7$.LEioN
} @,u/w4
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public PaginationSupport findPageByCriteria /D^"X
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(final DetachedCriteria detachedCriteria, finalint 1_
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startIndex){ 9h%?QC
return findPageByCriteria (+u39NQV
a,+@|TJ,i
(detachedCriteria, PaginationSupport.PAGESIZE, r'uGWW"w
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startIndex); 0B&Y]*
} 1~ t{aLPz
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public PaginationSupport findPageByCriteria 7.@TK&
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(final DetachedCriteria detachedCriteria, finalint x{,q]u /
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pageSize, P=&o%K,:f
finalint startIndex){ J?}WQLVP'
return(PaginationSupport) 2@~M4YJf
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getHibernateTemplate().execute(new HibernateCallback(){ C,NxE5?h
publicObject doInHibernate q7Dw_<
o{EC&-
(Session session)throws HibernateException { iMFgmM|
Criteria criteria = OY5OJ*
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detachedCriteria.getExecutableCriteria(session); Ns0cgCrhX
int totalCount = )+"'oY$]}
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((Integer) criteria.setProjection(Projections.rowCount !x>%+&c>k
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()).uniqueResult()).intValue(); \uq/x^?yo
criteria.setProjection ~7t$MF.
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(null); 0}FOV`n
List items = ""h)LUrl
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criteria.setFirstResult(startIndex).setMaxResults "/6:6`J
=w5O&(
(pageSize).list(); U_$qi
PaginationSupport ps = @~"anqT`
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new PaginationSupport(items, totalCount, pageSize, .tmiQ.
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startIndex); 6uKMCQ=h
return ps; /c-r
} ^/=#UQ*k
}, true); b}wC|\s
} k({\/t3i
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public List findAllByCriteria(final {
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DetachedCriteria detachedCriteria){ G,<T/f
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return(List) getHibernateTemplate A'K%WW*'U
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().execute(new HibernateCallback(){ j.ldaLdG
publicObject doInHibernate kR@Yl Yo
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(Session session)throws HibernateException { o/
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Criteria criteria = |*X*n*oI
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detachedCriteria.getExecutableCriteria(session); zYv#:>C8
return criteria.list(); |Uk"
{
} q;D+ai
}, true); F@!Td(r2
} -;XKcS7Ue
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public int getCountByCriteria(final Hb(B?!M)
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DetachedCriteria detachedCriteria){
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Integer count = (Integer) 0hn-FH-XE
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getHibernateTemplate().execute(new HibernateCallback(){ qcJft'>F
publicObject doInHibernate 70Yjv1i
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(Session session)throws HibernateException { Lru-u:
Criteria criteria = h~,JdDV8l*
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detachedCriteria.getExecutableCriteria(session); X$b={]b
return OR Wm
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criteria.setProjection(Projections.rowCount SL&hJs4c'
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()).uniqueResult(); sz):oea@f@
} 7"*|2Xq
}, true); \mN[gT}LHm
return count.intValue(); G02m/8g3
} LFp]7Dq
} .LRxP#B
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用户在web层构造查询条件detachedCriteria,和可选的 *Sf-;U
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )g@S%Yu
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PaginationSupport的实例ps。 a!c[!
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ps.getItems()得到已分页好的结果集 1fL<&G
ps.getIndexes()得到分页索引的数组 tAFti+Qb
ps.getTotalCount()得到总结果数 &~f3 psA
ps.getStartIndex()当前分页索引 FM5e+$>@
ps.getNextIndex()下一页索引 ql&*6KZ"
ps.getPreviousIndex()上一页索引 i_LF`JhEQT
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 MuEy>dl
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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 tue/4Q#7
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一下代码重构了。 =FBpo2^QB;
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我把原本我的做法也提供出来供大家讨论吧: @gBE{)Fj
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首先,为了实现分页查询,我封装了一个Page类: z&3]%t
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java代码: 1(GHCxA8G
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/*Created on 2005-4-14*/ d2ENm%q*PX
package org.flyware.util.page; "n\%_'R\hH
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/** >^"BEG9i:
* @author Joa jUjr6b"
* PI?j_8
*/ ^!;=6}Y R
publicclass Page { bYh9sO/l
zy N (4
/** imply if the page has previous page */ EZ(^~k=I
privateboolean hasPrePage; }Ewo_P&`
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/** imply if the page has next page */ L$Z(+6m5
privateboolean hasNextPage; qMS}t3X
_b4fS'[
/** the number of every page */ ;
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privateint everyPage; jlKGXD)Q[
fjDpwb:x)
/** the total page number */ /k"hH\Pp
privateint totalPage; K{}4zuZ
L]2<&%N2
/** the number of current page */ R+$8w2#
privateint currentPage; GG'Sp53GE
7-9;PkGG.A
/** the begin index of the records by the current =!-5+I#e
~ |,e_
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query */ ,R-Y~+!
privateint beginIndex; t&814Uf&\
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/** The default constructor */ iIU(
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public Page(){ Gbd?%{Xc-
U?U(;nSR\A
} e.6Dl_
`h;}3r#R{
/** construct the page by everyPage n2;9geq+
* @param everyPage 6;uBZ&g
* */ Plz-7fy33
public Page(int everyPage){ qCJ=Z
this.everyPage = everyPage; ~Y/z=^
} o G_~3Kt
~B@}R
/** The whole constructor */ cq^sq1A:
public Page(boolean hasPrePage, boolean hasNextPage, wt7.oKbW
i1/}XV
12r` )
int everyPage, int totalPage, 4NVgOr:
int currentPage, int beginIndex){ &?$\Y,{
this.hasPrePage = hasPrePage; Cals?u#U=
this.hasNextPage = hasNextPage; B {i&~k
this.everyPage = everyPage; Tj,Nmb>Q7'
this.totalPage = totalPage; rqvU8T7A
this.currentPage = currentPage; 6dT|;koWbm
this.beginIndex = beginIndex; 2_olT_#
} :2q
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/** W:ixzpQ
* @return pa]
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* Returns the beginIndex. -v*x V;[
*/ \FI^Vk
publicint getBeginIndex(){ |z7dRDU}]
return beginIndex; c=t*I0-OVS
} 8D~Dd!~P
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/** w?ai,Pw
* @param beginIndex ~&[u]u[
* The beginIndex to set. V/UB9)i+
*/ ;2W2MZ!TF
publicvoid setBeginIndex(int beginIndex){ RUrymkHFB
this.beginIndex = beginIndex; $u,GVq~
} "=`~iXT{e
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/** w:tGPort
* @return DM/hcY$MW
* Returns the currentPage. Y<ElJ>A2I
*/ $PfV<Yj'B
publicint getCurrentPage(){ >DmRP7v
return currentPage; 7jZrU|:yu(
} )%|r>{
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/** bf^ly6ml
* @param currentPage uf0^E3H
* The currentPage to set. V9$-twhu
*/ .5k^f5a
publicvoid setCurrentPage(int currentPage){ M7H~;S\3IM
this.currentPage = currentPage; xucIjPi]
} .%hQJ{vf-^
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/** Hrv),Ce
* @return Y=WR6!{
* Returns the everyPage. gx&7 3f<J
*/ #y`k$20"
publicint getEveryPage(){ e6es0D[>5
return everyPage; - coy@S=.'
} ~g96o81V
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/** Gm*Uv6?H?
* @param everyPage ht$ WF
* The everyPage to set. D1~^\)*
*/ [b pwg&Oo
publicvoid setEveryPage(int everyPage){ pgfu+K7?w
this.everyPage = everyPage; "]9_Fv
} D99N#36PU
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/** 8I {56$
* @return H!^C 2
* Returns the hasNextPage. u>
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*/ [EcV\.
publicboolean getHasNextPage(){ 4}PeP^pj
return hasNextPage; K+t];(
} 0wYiu
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/** {C, #rj
* @param hasNextPage ^8U6"O6|X
* The hasNextPage to set. ma`w\8a
*/ A9.;>8!u
publicvoid setHasNextPage(boolean hasNextPage){ 92NC]_jw
this.hasNextPage = hasNextPage; -q|*M:R
} | )S{(#k
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/** >T$7{
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* @return 3# :EK
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* Returns the hasPrePage. <X9T-b"$h
*/ dR%q1Y&`
publicboolean getHasPrePage(){ o|BFvhg
return hasPrePage; w-8)YJ Y
} -{r!M(47
f>b!-|
/** 5]Z] j[8Y
* @param hasPrePage } pSt@3o,
* The hasPrePage to set. N)Qlkz$X
*/ se"um5N-
publicvoid setHasPrePage(boolean hasPrePage){ jBGG2[hV
this.hasPrePage = hasPrePage; nEuct4BcL}
} MgSp.<!
xQ_:]\EZ
/** S@;&U1@h
* @return Returns the totalPage. GZ}*r{
* Y#.6d
*/ G-Zr M
publicint getTotalPage(){ V=Ww>
return totalPage; +,:nm_kQU
} W=!F8g|Qz
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/** +KYxw^k}"7
* @param totalPage Udg&
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* The totalPage to set. /6 A:J]Q_
*/ 2M5*bNU_:
publicvoid setTotalPage(int totalPage){ ArLz;#AOn
this.totalPage = totalPage; yg.\^C
} K7y!s :rg!
qb
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} .) ?2)Fl
dW:w<{a!R
T;xHIg4
f45;fT>
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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 |q9,,i}!
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个PageUtil,负责对Page对象进行构造: I>(;bNgNE
java代码: P<TpG0~(
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/*Created on 2005-4-14*/ Q;d+]xj
package org.flyware.util.page; H,01o5J
j
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import org.apache.commons.logging.Log; ]wJ}-#Kx
import org.apache.commons.logging.LogFactory; ZJ)3GF}4
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/** )<m=YI
;<
* @author Joa ~t1O]aO(
* {IF}d*:
*/ V7Vbl?*n
publicclass PageUtil { d)pz
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privatestaticfinal Log logger = LogFactory.getLog
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(PageUtil.class); ..v@Q%
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/** 1 P(&GYc
* Use the origin page to create a new page FCUVP,"T
* @param page rQ9?N^&!%
* @param totalRecords }L{_xyi>#
* @return Y#Sd2h,^X
*/ .rD#1)O
publicstatic Page createPage(Page page, int |*/uN~[
-k|g04Q?
totalRecords){ wC4AVJJ^>
return createPage(page.getEveryPage(), `!5tH?bX
$cp16
page.getCurrentPage(), totalRecords); UeutFNp
} @1`W<WP
*FI5z[8,
/** /ynKKJx<Y
* the basic page utils not including exception >llwNT
&Sa_%:*D(
handler \.XT:B_
* @param everyPage "W3n
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* @param currentPage Lqz}&A
* @param totalRecords qcpG}o+&D
* @return page }R?v"6aBS
*/ lN*1zM<6;
publicstatic Page createPage(int everyPage, int \(3Qqbw
u(TgWp5WF
currentPage, int totalRecords){ 0%q{UW2
everyPage = getEveryPage(everyPage); ^=heen<S%
currentPage = getCurrentPage(currentPage); [<@A8Q5,y
int beginIndex = getBeginIndex(everyPage, 8\W3FvQ
6qmo
ZAg
currentPage); BIHHRCe:@n
int totalPage = getTotalPage(everyPage, \]~kyy
ePPp)=
totalRecords); 2\$WP-)%
boolean hasNextPage = hasNextPage(currentPage, P^uP$D
LRqw\fKk[
totalPage); -=v/p*v0o
boolean hasPrePage = hasPrePage(currentPage); g9grfN
"'&>g4F`o
returnnew Page(hasPrePage, hasNextPage, )\:lYI}Wpm
everyPage, totalPage, *cI6&;y
currentPage, !z"a_
m;$F@JJ
beginIndex);
k=d%.kg
} 6@ (k8<3
nEZ-h7lzl(
privatestaticint getEveryPage(int everyPage){ q:D0$YY0
return everyPage == 0 ? 10 : everyPage; Rd@n?qB
} )U/@J+{{
fjz2m
privatestaticint getCurrentPage(int currentPage){ m`1}O"<&i
return currentPage == 0 ? 1 : currentPage; r~Is,.zZ}
} <*~BG)b
H*:r>Lm=
privatestaticint getBeginIndex(int everyPage, int I1}{~@
S9F]!m^i
currentPage){ ?
A^3.`
return(currentPage - 1) * everyPage; :g]HB,78
} ;)bF#@Q
04T*\G^:=
privatestaticint getTotalPage(int everyPage, int C6;](rN)N
%+j]vP
totalRecords){ s].'@_~s
int totalPage = 0; F%ylR^H>
STF}~`b:3
if(totalRecords % everyPage == 0) V+"*A
totalPage = totalRecords / everyPage; GQ8Dj!8
else H(*=9
totalPage = totalRecords / everyPage + 1 ; Pc\4QvQ8
K:lT-*+S
return totalPage; sLpCWIy
} U
K]{ ]-
v#YS`];B
privatestaticboolean hasPrePage(int currentPage){ vSHIl"h
return currentPage == 1 ? false : true; "n2xn%t{
} zdpLAr
0o^#Fmuz
privatestaticboolean hasNextPage(int currentPage, WriJco<v
N6m*xxI{
int totalPage){ (
_F
return currentPage == totalPage || totalPage == lDX&v$
%q\P 'cK
0 ? false : true; ~%!U,)-
} GXvo't@N
f'?6D+Yw~
]mLTF',5
} H*
JC`:
X7B)jH%N
pmpn^ZR
sR0e&Y
qKb-aP-
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。 /j5-
"<;.
uZ39Vx
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 Y_ ;i
x#}eC'Q
做法如下: 1 0Tg> H
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 AB|VO4-?
p(b1I+!
的信息,和一个结果集List: =g>7|?6>=
java代码: D 5wR?O
2KNKdV3NK
HBf8!\0|/
/*Created on 2005-6-13*/ ]bU'G$Qm&s
package com.adt.bo; x)qHeS
i:N^:%
import java.util.List; %dWFg<< |
~9>[ U%D
import org.flyware.util.page.Page; ;g)Fhdy!
=A&*SE o5
/** 5]n<%bP\
* @author Joa !Pjg&19
*/ +Gwe%p Q
publicclass Result { CCvBE, ux
p(&o'{fb
private Page page; Y`_X@Q
{*r$m>HpM
private List content; <}'B-k9
VNEZBy"F
/** Ru\Lr=9
* The default constructor 3[O =2
*/ nm|m1Z+U
public Result(){ 3Os3=Ix
super(); O.8m%ZjD
} 4a50w:Jy]
YH+\rb_
/** gm\o>YclS
* The constructor using fields X\)KVn`
* Y>!W&Gtu
* @param page 6!D
* @param content oHFDg?Z`
*/ Z.OrHg1
public Result(Page page, List content){ .p*D[o2 9
this.page = page; I)/7M}t`
this.content = content; <|.! Px86
} vrO$8* sy
,(kXF:
/** {-]HYk
* @return Returns the content. ='||BxB
*/ A VG`r2T
publicList getContent(){ NX #d}M^V
return content; 8!`.%)- 4
} adPU)k_j:
Lj* =*V
/** !!X9mI|2|
* @return Returns the page. teNQUIe-
*/ I=Dk'M
public Page getPage(){ ymVd94L
return page; 4bjp*1 *]
} 7,VWvmWJex
bh6wI%8H
/** W%ZU& YBc
* @param content l*MUDT@M8\
* The content to set. v?=VZ~`O(
*/ P\0%nyOG(%
public void setContent(List content){ }Fe{s;
this.content = content; gbv[*R{<%
} h_"/@6
ij5=f0^4.
/** Im1qWe
* @param page BU{V,|10a
* The page to set.
]p.f*]
*/ 0$Db@
publicvoid setPage(Page page){ wyEgm:Vt
this.page = page; ;pK"N:|
} i4Cb&h^
} KKJ [
;9\0x
69[k
?')LM
vXZz=E
AH
3;gtuqwD$
2. 编写业务逻辑接口,并实现它(UserManager, K1nwv"
S.>9tV2Ca
UserManagerImpl) y+x>{!pw
java代码: 5i&V ~G
u;1NhD<n
n=MYv(Pp}
/*Created on 2005-7-15*/ jM<Ihmh|
package com.adt.service; 7B :aJfxM
L%Hm#eFx
import net.sf.hibernate.HibernateException; B\w`)c
DQQjx>CK
import org.flyware.util.page.Page; IKpx~
FeRuZww._J
import com.adt.bo.Result; 64s;6=
rqo<Xt`
/** $^ 3 f}IzA
* @author Joa v> PHn69PU
*/ e-t`\5b;
publicinterface UserManager { {<BK@U
>p:fWQ6
public Result listUser(Page page)throws h"S/D[
.H.v c_/
HibernateException; ^:j:;\;
<p
.[E]a2_
} g5\B- 3{
\H12~=p`B
en":
Lj,%pz J
@SB+u+mOS
java代码: r\`m[Q
ir?9{t/()
Ip-jqN J~
/*Created on 2005-7-15*/ }H.vH
package com.adt.service.impl; cv1L!Ce,
go5!zSs
import java.util.List; Jz b".A
>f/g:[
import net.sf.hibernate.HibernateException; t$|6}BX
yh<aFYdk
import org.flyware.util.page.Page; =,]M$M
import org.flyware.util.page.PageUtil; k]sT'}[n
~`.%n7
import com.adt.bo.Result; |XZf:}q5:
import com.adt.dao.UserDAO; u9(AT>HxT
import com.adt.exception.ObjectNotFoundException; C(hg"_W ou
import com.adt.service.UserManager; + k:?;ZG
?Fv(4g
/** Lo4t:H&
* @author Joa ks4
,2f,2
*/ n4,J#h/
publicclass UserManagerImpl implements UserManager { %9M49s
x$I>e
private UserDAO userDAO; MG>;|*$%
u>Hx#R<*%
/** X=~QE}x
* @param userDAO The userDAO to set. #n
r1- sf|
*/ M$9h)3(B
publicvoid setUserDAO(UserDAO userDAO){ y0]O 6.{
this.userDAO = userDAO; sqRuqUj+
} Vo[4\h#$
,Nh X%
/* (non-Javadoc) RPwSo.c4
* @see com.adt.service.UserManager#listUser Cv33?l-8%_
$_kU)<e3
(org.flyware.util.page.Page) 4+"SG@i`W
*/ $la,_Sr
public Result listUser(Page page)throws Y.J$f<[R
~~mQ
HibernateException, ObjectNotFoundException { (z{xd
int totalRecords = userDAO.getUserCount(); uyIA]OtyN
if(totalRecords == 0) , 88}5)b[
throw new ObjectNotFoundException s]UeDZ<a
P])O\<)J
("userNotExist"); K~R{q+
page = PageUtil.createPage(page, totalRecords); C/G[B?:h
List users = userDAO.getUserByPage(page); j/&7L@Y
returnnew Result(page, users); .rHO7c,P~
} ?*=Jq
7
pV3#fQ
} L\I/2aiE
~MF. M8
_nUuiB>
,*US) &x
Y!zlte|P
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m{|n.b
!v=ha%w{
询,接下来编写UserDAO的代码: NT 'Y h
3. UserDAO 和 UserDAOImpl: =1C9lKm
java代码: %VCHM GP=
t*#T~3p
J5wq}<8
/*Created on 2005-7-15*/ Zh*I0m
package com.adt.dao; w'C(? ?mH
FU zY&@Y
import java.util.List; =
4L.
e!#:h4I
import org.flyware.util.page.Page; wuCODz@~
t [f]
import net.sf.hibernate.HibernateException; ,
{^g}d8
%|Vq"MW,I
/** 1ARIZ;H
* @author Joa ^Ue>T8
*/ W;7cF8fu4
publicinterface UserDAO extends BaseDAO { a9%#
J^!
[/FIY!nC?
publicList getUserByName(String name)throws L-yC 'C
Flsf5 Tr0
HibernateException; zK v}J
}/|1"D
publicint getUserCount()throws HibernateException; t V</x0#
}I"^WCyH
publicList getUserByPage(Page page)throws 38F8(QU{
kq+L63fZ
HibernateException; NR" Xn7G
hz!.|U@,{<
} o/&Q^^Xj^~
G"]'`2.m
*=rl<?tX
@L0.Z1 ).
sqhM[u
k
java代码: }QK-@T@4<
o 0B`~7(
gO29:L[t
/*Created on 2005-7-15*/ /1YqDK0
package com.adt.dao.impl; N]3XDd|q
d}1R<Q;F
import java.util.List; tG'c79D\
!U@[lBW
import org.flyware.util.page.Page; K=V)"v5o3
)9s[-W,e
import net.sf.hibernate.HibernateException; CAk.2C/
import net.sf.hibernate.Query; +NQw^!0qy
yo5|~"yZY
import com.adt.dao.UserDAO; t2>Vj>U
BO^e.iB/
/** c8h
9
* @author Joa /) N[tv2
*/ }0:=)e
public class UserDAOImpl extends BaseDAOHibernateImpl !^w+<p
`3~w#?+=*
implements UserDAO { w;XX jT
ffd yDUzQ
/* (non-Javadoc) z'
@F@k6
* @see com.adt.dao.UserDAO#getUserByName ~e|~c<!z8@
|#k1a:
(java.lang.String) <Fi/!
*/ =4G9ev
4
publicList getUserByName(String name)throws Hc71 .rqS
krgsmDi7
HibernateException { _15r!RZ:1
String querySentence = "FROM user in class :2La,
1Ypru<.)W
com.adt.po.User WHERE user.name=:name"; rQU;?[y
Query query = getSession().createQuery WlU5`NJl]2
mAz':R[
(querySentence); }2}hH0R
query.setParameter("name", name); "[76>\'H
return query.list(); >k"/:g^t
} Zx@{nVoYe~
EI'(
/* (non-Javadoc) N/(&&\3
* @see com.adt.dao.UserDAO#getUserCount() OX!9T.j
*/ QM
O OJA
publicint getUserCount()throws HibernateException { M^a QH/=:"
int count = 0; Gt' %:9r
String querySentence = "SELECT count(*) FROM I_4'9
P'[w9'B
user in class com.adt.po.User"; u>}k+8~
Query query = getSession().createQuery mjfU[2
MbYAK-l.h
(querySentence); 6#v"+V
count = ((Integer)query.iterate().next ZhW>H
Y<l{DmrsA
()).intValue(); |iJ37QIM
return count; S7@.s`_{w
} G0^NkH,k
0GEK xV\F
/* (non-Javadoc) M '[.ay
* @see com.adt.dao.UserDAO#getUserByPage ,u/GA<'#M
CtS*"c,j
(org.flyware.util.page.Page) nI&Tr_"tm
*/ 72.ZE%Ue
publicList getUserByPage(Page page)throws Ygr1 S(=
[/xw5rO%
HibernateException { lj(}{O
String querySentence = "FROM user in class KnKV+:"
7Q2"]f,$CQ
com.adt.po.User"; \f.ceh;!
Query query = getSession().createQuery bmFnsqo
s#>Bwn&b)
(querySentence); j*xxOwf
query.setFirstResult(page.getBeginIndex()) {x
s{
.setMaxResults(page.getEveryPage()); ULj'DzlfH
return query.list(); J"# o #~
} &jr'vS[b
y]yp8Bs+
} x pT85D
#)z_TM07P
pPUKx=d
'Tj9btM*cL
&^92z:?
至此,一个完整的分页程序完成。前台的只需要调用 ZBi|BD
q<dZy? f
userManager.listUser(page)即可得到一个Page对象和结果集对象 x
xWnB
a2/!~X9F
的综合体,而传入的参数page对象则可以由前台传入,如果用 g^/
3+rud9T
webwork,甚至可以直接在配置文件中指定。 adRvAq]mA
]25 x X
下面给出一个webwork调用示例: blEs!/A`
java代码: {dTtYL$'"
@|sDb?J
[kaj8
/*Created on 2005-6-17*/ r$<[`L+6
package com.adt.action.user; 1 :<f[l
8SR ~{
import java.util.List; _gxI=EYi
_Gvn1"l
import org.apache.commons.logging.Log; 8K=sx@l
import org.apache.commons.logging.LogFactory; 1--_E,Su>
import org.flyware.util.page.Page; kO>F, M
.IXkdy
import com.adt.bo.Result; |]y]K%
import com.adt.service.UserService; v!JQ;OX
import com.opensymphony.xwork.Action; BxVo>r
0rP`BK|
/** b S[;d5
* @author Joa p'tB4V qT
*/ 5ELKL#(
publicclass ListUser implementsAction{ Zl^#U c"
bxLeQWr6
privatestaticfinal Log logger = LogFactory.getLog )2~Iqzc4
Ev+m+
(ListUser.class); ~H`~&?
3Uw}!>`%
private UserService userService; {a;my"ly
JI##l:,7r
private Page page; R-5EztmLae
XpFW(v
privateList users; ;n0VF77>O
h2<Y*j
/* JL.noV3q$
* (non-Javadoc) =wE1j
* Pv,Q*gh`
* @see com.opensymphony.xwork.Action#execute() LX5, _`B
*/ ]#x!mZ!
publicString execute()throwsException{ b+7!$
Result result = userService.listUser(page); Y=94<e[f"
page = result.getPage(); n o).70K
users = result.getContent(); M@%$9N)gd
return SUCCESS; KElzYZl8
} 99)m d
IWc?E
/** >,;,
6|S
* @return Returns the page. F-0 |&0
*/ /a@gE^TM
public Page getPage(){ jG~zpZh
return page; Y_S>S(0
} fR]%:'2k
BUhLAO
/** w=Cqv~
* @return Returns the users. >AFX}N#
*/ l.gt+e
publicList getUsers(){ EdgcdSb7
return users; %VZQX_
} TX/Ng+v S
fZ8at
/** z;fi
* @param page /8](M5X]f
* The page to set. 5BWO7F0v"
*/ vuP.V#
publicvoid setPage(Page page){ SI-G7e)3;>
this.page = page; H!uB&qY
} 'a1%`rzm
VkKq<`t<
/** LNm{}VJ%
* @param users U TT 7a"
* The users to set. q4Z9;^S
*/ c^Y&4=>T
publicvoid setUsers(List users){ wlvh DJ
this.users = users; e[`u:
} Qqju6} +
B-EVo&.
/** ;}/@ar7s3
* @param userService KNH.4A ,
* The userService to set. z^xrB$8
u
*/ cU`sA_f
publicvoid setUserService(UserService userService){ n+Bh-a V
this.userService = userService; fYv= yP~
} gt~hUwL
} _DlkTi5(w
4|PNsHXt
\*24NB
<0?h$hf4c
7J:zIC$u>
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, @#wBK3Ut^
Tno[LP,
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 1#o><
?
7soiy
A
么只需要: 9t `
java代码: Xn<~ln
#:C?:RMS
SiBhf3
<?xml version="1.0"?> =Tdh]0
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 5|I2
e7fA-,DV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- A$w0+&*=
$8kQM
1.0.dtd"> Mwm=r//
_9@D o6
<xwork> ?hW?w$C
7hQf
T76h
<package name="user" extends="webwork- f(Hh(
Lbo8>L(
interceptors"> Woo2hg-ti
lz=DP:/&
<!-- The default interceptor stack name &PfCY{_
z?a<&`W
--> 0H|U9
<default-interceptor-ref ve#*qz Y
=e<;B_~.
name="myDefaultWebStack"/> y1zNF$<q
W`$D*X0*o
<action name="listUser" |(mr&7O
-]!m4xvK
class="com.adt.action.user.ListUser"> v7;zce/~
<param H*SEzVb
rkp 1tv
name="page.everyPage">10</param> bC[TLsh7{2
<result %j
'_I\
>,ThIwRN
name="success">/user/user_list.jsp</result> jQrj3b.NC3
</action> .iDxq8l
5P?7xRA
</package> .*9+%FN
@PYCl
</xwork> T);eYC"@
v^Vr^!3
XET'XJWF%
8(.DI/
;B8#Nf
>lD*:#o
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 )kMA_\$,
FW?zJ
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。 QFg,pTj
m
6Xex.d
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !^o(?1
bp'qrcFuiL
(WW*yv.J
>g ):xi3qK
+Lq;0tRC
我写的一个用于分页的类,用了泛型了,hoho VxlK:*t`
994
java代码: ."N`X\
x2P}8Idg?A
3'
HtT
package com.intokr.util; {I/|7b>@r
rZ.,\ X_
import java.util.List; r*-e~
mp^;8??;
/** @uIY+_E40g
* 用于分页的类<br> lq4vX^S
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ZcTxE]Y
* ?dWfupO{
* @version 0.01
2r3]DrpJ
* @author cheng ] D(laqS;"
*/ %?o@YwBo^E
public class Paginator<E> { $_2S,3 }
privateint count = 0; // 总记录数 R@h@@lSf
privateint p = 1; // 页编号 IW48Sg
privateint num = 20; // 每页的记录数 'f+g`t?
privateList<E> results = null; // 结果 Z0f0tL&A<
MNy)= d&<P
/** >e]46K
* 结果总数 iQrTEp
*/ r_sZw@lqJ
publicint getCount(){ *O`76+iZ|_
return count; ?;\xeFy!
} (-lu#hJ`&r
os\"(*dix
publicvoid setCount(int count){ c0lVt)pr/
this.count = count; c|f)k:Q
} D$sG1*@s-
_}_lrg}U
/** ;$ot,mH?T
* 本结果所在的页码,从1开始 1wx&/#a
*
MX3ss,F
* @return Returns the pageNo. h6!o,qw"
*/ /eM_:H5
publicint getP(){ p1dqDgF*
return p; i(eLE"G+
} 9Y9pKTU
E8-8E2i,
/** @$5!
* if(p<=0) p=1 :+1S+w
* RETq S
* @param p C:$12{I?*
*/ QK+s}ny
publicvoid setP(int p){ MoKGnb
if(p <= 0) eRlJ
p = 1; n&?]GyQ
this.p = p; Z19d Ted33
} UOWOOdWSB
*{5L*\AZ
/** @ 2mJh^cj
* 每页记录数量 zTFfft<
*/ -0KQR{LI
publicint getNum(){ $Cr? }'a
return num; )~hsd+ 0t
} !Ua74C
Y(>]7
/** {.W$<y (j7
* if(num<1) num=1 e`1,jt'
*/ %cM2;a=2
publicvoid setNum(int num){ X@,xwsM%tb
if(num < 1) SE0"25\_G
num = 1; xg'FC/1LD
this.num = num; T=8>0D^v5
} ulnG|3A9
&Wj
%`T{
/** D`r^2(WW
* 获得总页数 O5PCR6U
*/ i!/V wGg
publicint getPageNum(){ C[j'0@~V:B
return(count - 1) / num + 1; T)o)%Yv
} `jR = X
URW#nm?
/** M5C}*c9
* 获得本页的开始编号,为 (p-1)*num+1 PVAs# ~
*/ {7`eR2#Wq
publicint getStart(){ buGYHZu
return(p - 1) * num + 1; RH,(8 .&>r
} urT!?*g,
`pp"htm
/** MKd{y~'
* @return Returns the results. 8-cB0F=j_
*/ a#X[V5|6Q
publicList<E> getResults(){ s[:e '#^
return results; -\;x>=#B
} e_6@oh2s-
U8?%Dq%i
public void setResults(List<E> results){ W,zlR5+Jk
this.results = results; EP#3+BsH
} OQ<|XdI$
$CaF"5}?Ke
public String toString(){ 6MfjB@
StringBuilder buff = new StringBuilder ;4nz'9+
.K(IRWuw
(); zosJ=$L
buff.append("{"); *Yk3y-
buff.append("count:").append(count); w{[OtGIi3
buff.append(",p:").append(p); pCSR^ua>
buff.append(",nump:").append(num); 7Rr(YoWa
buff.append(",results:").append C& 0iWY\a
/nEh,<Y)
(results); E Kks8
buff.append("}"); [wAI;=.
return buff.toString(); "}PaMR]
} TY"=8}X1
6xSdA;<+]
} `gq@LP"o
3_(fisvx
n!mtMPH$