Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 YT8q0BR]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `WH$rx!
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 c!\T0XtT
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 By6O@ .\V
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分页支持类: NB<8M!X/
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java代码: BC!) g+8
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package com.javaeye.common.util; <k8WnA ~Fl
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import java.util.List; SM)"vr_
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publicclass PaginationSupport { pmBN?<
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publicfinalstaticint PAGESIZE = 30; =_=%1rI~
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privateint pageSize = PAGESIZE; \2+ngq)
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privateList items; j.6!T'$|
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privateint totalCount; vKW!;U9~P
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privateint[] indexes = newint[0]; >k\p%{P
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privateint startIndex = 0; *2/qm:gB
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public PaginationSupport(List items, int *PlKl_nP6
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totalCount){ #QsJr_=
setPageSize(PAGESIZE); ~Qif-|[V
setTotalCount(totalCount); W2-l_{
setItems(items); eb}XooX
setStartIndex(0); ncadVheKt
} eXsp0!v
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public PaginationSupport(List items, int ,#BD/dF
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totalCount, int startIndex){ v B~VJKD
setPageSize(PAGESIZE); 1F>8#+B/W
setTotalCount(totalCount); >q?{'#i
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setItems(items); Ys_LGfK
setStartIndex(startIndex); ,)U%6=o#}
}
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public PaginationSupport(List items, int @$kzes\
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totalCount, int pageSize, int startIndex){ 416}# Mk
setPageSize(pageSize); }LS.bQKqi,
setTotalCount(totalCount); cV1E<CM
setItems(items); A`~?2LH,~F
setStartIndex(startIndex); J"h2"$v,
} s^6,"C
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publicList getItems(){ Y5ei:r|^
return items; e]>=;Zn
} L$"x*2[A
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publicvoid setItems(List items){ ^o>WCU =
this.items = items; hN0h'JJ[7
} T>*G1 -J#
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publicint getPageSize(){ SJc*Rl>
return pageSize; zV15d91GX
} OcpvY~"Pr
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publicvoid setPageSize(int pageSize){ t:oq't
this.pageSize = pageSize; Hr]
} n]3'N58
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publicint getTotalCount(){ I)jAdd
return totalCount; P!j*4t
} #68$'Rl"o1
o*d (;
publicvoid setTotalCount(int totalCount){ *j <#5=l
if(totalCount > 0){ XgUSJ*
this.totalCount = totalCount; ;InMgo,
int count = totalCount / ow`F 7
; %AgKgV
pageSize; h<'tQGC
if(totalCount % pageSize > 0) {@x-T
count++; MYxuQ |w
indexes = newint[count]; 8eh3K8tL#
for(int i = 0; i < count; i++){ Rm,>6bQx
indexes = pageSize * DBu8}2R
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i; m4~~ q[t
} e8_EB/)_Z
}else{ [*C~BM
this.totalCount = 0; |_s,]:
} &0ymAf5R
} fOsvOC
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publicint[] getIndexes(){
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return indexes; cj2^wmkB
} 8/P!i2o
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publicvoid setIndexes(int[] indexes){ wJgH15oB
this.indexes = indexes; ns/*WH&[x
} hSps9*y
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publicint getStartIndex(){ Y>2#9LA
return startIndex; 4`V&Yqwl
} DbR!s1ux
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publicvoid setStartIndex(int startIndex){ R:^jQ'1
if(totalCount <= 0) )*.rl
this.startIndex = 0; 8{&.[SC7
elseif(startIndex >= totalCount) /
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this.startIndex = indexes &u<%%b|
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[indexes.length - 1]; PCH$)F4^
elseif(startIndex < 0) (v0Q.Q@<
this.startIndex = 0; |1(L~g
else{ p~(STHDe#
this.startIndex = indexes (
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vMJ_n=Vf
[startIndex / pageSize]; AOqL&z
} {?cF2K#
} f&Sovuuh
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publicint getNextIndex(){ ']^]z".H
int nextIndex = getStartIndex() + 9m"EY@-
LS-_GslE7\
pageSize; /Ea&Zm
if(nextIndex >= totalCount) [*H h6
return getStartIndex(); SapVS*yx@
else J'I1NeK
return nextIndex; ]%G#x
} k$Ug;`v#
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publicint getPreviousIndex(){ Hr}\-$
int previousIndex = getStartIndex() - K'K/}q<
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pageSize; *iSE)[W
if(previousIndex < 0) 9`&sZ|"3
return0; m_;XhO
else W=n
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return previousIndex; bc& 5*?
} & TN.6Hm3
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} vXak5iq>X
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抽象业务类 K@"B^f0mU
java代码: 9S5C{~P4
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/** @,]$FBT"5
* Created on 2005-7-12 +}f}!h;
*/ zgxMDLH
package com.javaeye.common.business; P (fWJVF7
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import java.io.Serializable; N=@8~{V.
import java.util.List; }C
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import org.hibernate.Criteria; +a+DiD>./
import org.hibernate.HibernateException; !]8QOn7 =
import org.hibernate.Session; GCxmqoQ
import org.hibernate.criterion.DetachedCriteria; iW[%|ddk
import org.hibernate.criterion.Projections; &sJ6k/l
import 6ziBGU#.-
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org.springframework.orm.hibernate3.HibernateCallback; y@ c[S;
import `mS0]/AV/
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org.springframework.orm.hibernate3.support.HibernateDaoS a0`(*#P
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upport; ]-w.x]I
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import com.javaeye.common.util.PaginationSupport; V$ "]f6
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public abstract class AbstractManager extends 5^N`~
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HibernateDaoSupport { 6MQyr2c
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privateboolean cacheQueries = false; j__l'?s
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privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean 8y]{I^z}
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cacheQueries){ +"VXw2R_e
this.cacheQueries = cacheQueries; uAV-wc
} YcM0A~<
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publicvoid setQueryCacheRegion(String q)RTy|NJ^
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queryCacheRegion){ %eJE@$
this.queryCacheRegion = 8HDI]
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queryCacheRegion; cXt]55"
} 3Zm;:v4y
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publicvoid save(finalObject entity){ @KU^B_{i
getHibernateTemplate().save(entity); 5&}p'6*K
} JzkI!5c<j
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publicvoid persist(finalObject entity){ S\6.vw!'
getHibernateTemplate().save(entity); FivqyT7i
} (5)DQ1LaF
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publicvoid update(finalObject entity){ Gp1?drF6
getHibernateTemplate().update(entity); .QDeS|l
} bD V/$@p
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publicvoid delete(finalObject entity){ [9~6, ;6
getHibernateTemplate().delete(entity); :\|<7n
} @E?o~jO(e
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publicObject load(finalClass entity, W>E|Iv[o
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finalSerializable id){ #M[%JTTn
return getHibernateTemplate().load R(#ZaFuo[
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(entity, id); {0\9HI@
} ] U.*KkQ
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publicObject get(finalClass entity, ]=(PtzVa
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finalSerializable id){ MJy(B><
return getHibernateTemplate().get &>vfm9
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(entity, id); luCwP
} N$P\$
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publicList findAll(finalClass entity){ yjIA`5^
return getHibernateTemplate().find("from M)sAMfuUw
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" + entity.getName()); J{PNB{v
} rch Kr w
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publicList findByNamedQuery(finalString x]~&4fp
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namedQuery){ GyQvodqD
return getHibernateTemplate /q?gpy
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().findByNamedQuery(namedQuery); jXYjs8Iy
} *fQn!2}=(
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publicList findByNamedQuery(finalString query, NwNjB
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finalObject parameter){ ~SYW@o
return getHibernateTemplate h.5KzC
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().findByNamedQuery(query, parameter); Z~ u3{
} x,TnYqT^
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publicList findByNamedQuery(finalString query, /NQ
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finalObject[] parameters){ @oQ"FLF.
return getHibernateTemplate T
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().findByNamedQuery(query, parameters); -{NP3zy
} N, 4hh?
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publicList find(finalString query){ cue aOtD
return getHibernateTemplate().find Fmzkbt~oe
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(query); @]dv
} ,iXQ"):!OB
q I*7ToBJ
publicList find(finalString query, finalObject ]E#W[6'VtB
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parameter){ Uz%2{HB@{
return getHibernateTemplate().find :}-izd)/j
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(query, parameter); ;Swy5z0=ro
} eQ<Vky^SJ
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public PaginationSupport findPageByCriteria I?_WV_T&
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(final DetachedCriteria detachedCriteria){ okTqq=xd`
return findPageByCriteria RM>A9nv$\
,@\z{}~v
(detachedCriteria, PaginationSupport.PAGESIZE, 0); AYfL}X<Ig
} F12$BKDH
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public PaginationSupport findPageByCriteria Z:YgG.z"
gi$ 'x^]#
(final DetachedCriteria detachedCriteria, finalint v1=N?8Hz1
RSCQ`.
startIndex){ hp@F\9j
return findPageByCriteria WAJKP"
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(detachedCriteria, PaginationSupport.PAGESIZE, ^0?ww&X
$.4N@=s,?c
startIndex); *0'< DnGW
} (6&"(}Pai
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public PaginationSupport findPageByCriteria 2?:'p[z"]
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(final DetachedCriteria detachedCriteria, finalint FcyFE~>2
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pageSize, ,\N4tG1\
finalint startIndex){ 8+H 0
return(PaginationSupport) uZ'(fnZ$
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getHibernateTemplate().execute(new HibernateCallback(){ m[Mw2 F
publicObject doInHibernate T[MDjhv'
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(Session session)throws HibernateException { W
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Criteria criteria = N?O^"
4gZ)9ya
detachedCriteria.getExecutableCriteria(session); WJMmt XO
int totalCount = #/HZ[Vw
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f
((Integer) criteria.setProjection(Projections.rowCount }zqo<o
v#e*RI2}
()).uniqueResult()).intValue(); [I/ZzDMX
criteria.setProjection U2CC#,b!(
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(null); Y*IKPnPot2
List items = (-`PO]e48
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criteria.setFirstResult(startIndex).setMaxResults wN^^_
AQ,"):ofvT
(pageSize).list(); ./^8L(
PaginationSupport ps = |9X2AS Qu
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new PaginationSupport(items, totalCount, pageSize, 5rmQ:8_5
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startIndex); :#cJZ\YH
return ps; dI>cPqQ
} ;aD?BD__Z
}, true); WD! " $
} D1@yW}
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public List findAllByCriteria(final o-JB,^TE
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DetachedCriteria detachedCriteria){ 'K01"`#
return(List) getHibernateTemplate +ej5C:El_}
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().execute(new HibernateCallback(){ $4qM\3x0,
publicObject doInHibernate ]9c{qm}y
c
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(Session session)throws HibernateException { {Ppb ;
Criteria criteria = C6h[L
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detachedCriteria.getExecutableCriteria(session); 4wGBB{X
return criteria.list(); y&bZai8WlE
} )u4=k(
}, true); RCoDdtMo
} Y88N*axDW.
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public int getCountByCriteria(final 8&3&^!I
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[
DetachedCriteria detachedCriteria){ R&g&BF
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ ]w0Y5H "
publicObject doInHibernate K9yZG
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(Session session)throws HibernateException { S)W?W}*R\
Criteria criteria = U<>@)0~7g!
2|]
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detachedCriteria.getExecutableCriteria(session); :SWrx MT
return ^f-)gZ&
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criteria.setProjection(Projections.rowCount dLeos9M:
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()).uniqueResult(); 9a_UxF+6/
} UEt78eN
}, true); ;b. m X
return count.intValue(); r!w*y3
} %M/L/_d
} dw!Xt@,[g{
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用户在web层构造查询条件detachedCriteria,和可选的 nh80"Ny5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 g_k95k3V'
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PaginationSupport的实例ps。 %e)vl[:}
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ps.getItems()得到已分页好的结果集 "Mv^S'?>
ps.getIndexes()得到分页索引的数组 xj&~>&U){;
ps.getTotalCount()得到总结果数 r'_#rl
ps.getStartIndex()当前分页索引 2
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ps.getNextIndex()下一页索引 g
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ps.getPreviousIndex()上一页索引 k6GQH@y!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ZCb@!V}=
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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 AW9%E/{
&e#pL`N
一下代码重构了。 xaV3N[Zd
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我把原本我的做法也提供出来供大家讨论吧: 0}'/p N>
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首先,为了实现分页查询,我封装了一个Page类: xdY'i0fh
java代码: AXi4{Q,
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/*Created on 2005-4-14*/ IM[=]j.?
package org.flyware.util.page; a8%T*mk(
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/** */TO$ ^s
* @author Joa ;eO Ye3;c
* 3+:NX6Ewb*
*/ <Nc9F['
publicclass Page { #>BC|/P}
/BF7N3
/** imply if the page has previous page */ L=s8em]7l
privateboolean hasPrePage; N "eK9>
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/** imply if the page has next page */ -~lrv#5Q
privateboolean hasNextPage; 2!{_x8,n
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/** the number of every page */ o$*DFvk
privateint everyPage; 4xFAFK~lx
[`KQ\4u
/** the total page number */ 8-b~p
privateint totalPage; &qa16bz
wjOqCF"
/** the number of current page */ T).}~i;!
privateint currentPage; (.{. "
soKR*gJ,
/** the begin index of the records by the current Tilr%D(Q
pMp@W`i^6
query */ 3z8zZ1uzU
privateint beginIndex; k<"N^+GSz
:b#5cMUe
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/** The default constructor */ MUN:}S
public Page(){ SBw'z(U
jar?"o
} R/^;,.
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/** construct the page by everyPage g|!=@9[dv
* @param everyPage ~<osL
* */ h 'is#X 6:
public Page(int everyPage){ Me;Nn$'%
this.everyPage = everyPage; !A_KCM:Ym
} ];0:aSi#
a$6pA@7}
/** The whole constructor */ a1weTn*
public Page(boolean hasPrePage, boolean hasNextPage, 2Ju,P_<dt
OQT i$2
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int everyPage, int totalPage, |e3YTLsI
int currentPage, int beginIndex){ qv/chD`C
this.hasPrePage = hasPrePage; U(:t$SBKy
this.hasNextPage = hasNextPage; / pR,l5
this.everyPage = everyPage;
+!wkTrV
this.totalPage = totalPage; k_%maJkXp
this.currentPage = currentPage; yhyh\.
this.beginIndex = beginIndex; .fY$$aD$4
} Z?w=-
I,lzyxRP
/** @{8805Dp
* @return a3(f\MMxE
* Returns the beginIndex. nSU7,K`PM
*/ VU|Cct&)
publicint getBeginIndex(){ c-a;nAR
return beginIndex; jY\YSQ
} u+8?'ZT,
2?owXcbx
/** !E\J`K0_e
* @param beginIndex TC'^O0aZ_
* The beginIndex to set. H0mDs7
*/ ,u>K##X\
publicvoid setBeginIndex(int beginIndex){ 9'JkLgz;d+
this.beginIndex = beginIndex; 'MIM_m)H
} 7kidPAhY
,1e@Y~eZ
/** a^&3?3
* @return /?QBMI
* Returns the currentPage. 2c<phmiK
*/ <8/lHQ^\)
publicint getCurrentPage(){ 93#wU})
return currentPage; GpM_Qp
} &rxR"^x\
/d-7n|#E
/** pG:)u
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* @param currentPage u8@>ThPD
* The currentPage to set. ]qc2jut"
*/ tt>=Vt'
publicvoid setCurrentPage(int currentPage){ gs77")K&
this.currentPage = currentPage; U
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} x;R9Gc[5
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axSL
/** n-_-;TYH
* @return V|fs"HY
* Returns the everyPage. lq!l{[Xp
*/ u5FlT3hY.
publicint getEveryPage(){ >
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return everyPage; }c,}V
} [.7d<oY
X:"i4i[}{9
/** l` lk-nb
* @param everyPage ].w4$OJ?
* The everyPage to set. ]nn98y+
*/ A4x]Qh3OO
publicvoid setEveryPage(int everyPage){ QOGvC[*`<T
this.everyPage = everyPage; {L{o]Ii?g
} s%7t"-=&
F]O`3e=!
/** EH J.T~X
* @return Tv,[DI +
* Returns the hasNextPage. L\J;J%fz.
*/ jp%S3)
publicboolean getHasNextPage(){ .5_2zat0H
return hasNextPage; 8b&/k8i:
} Cv.C;H
N)X3XTY
/** Z"xvh81P
* @param hasNextPage `r6 ,+&
* The hasNextPage to set. WaRw05r
*/ i>`%TW:g
publicvoid setHasNextPage(boolean hasNextPage){ ^}=,g
this.hasNextPage = hasNextPage; ,?%Zc$\LW
} >1Ibc=}g
GR_-9}jQP
/** z43M]P<
* @return +{.WQA}z\
* Returns the hasPrePage. m+[Ux{$
*/ jvL[
JI,b
publicboolean getHasPrePage(){ )mT<MkP
return hasPrePage; )*J^K?!S
} oJz^|dW
1.GQau~
/** <iC(`J$D
* @param hasPrePage N=}A Z{$
* The hasPrePage to set. i[3'ec3
*/ zTSTEOP}%Y
publicvoid setHasPrePage(boolean hasPrePage){ IOmfF[
this.hasPrePage = hasPrePage; 904}Jh,
} 2HA:"v8
R&k<AZ
/** N~)_DjQP5
* @return Returns the totalPage. "<1{9
* yR{3!{r3(
*/ ;N0XFjdR
publicint getTotalPage(){ ^hM4j{|&M
return totalPage; kdeWip6Y
} q>+k@>bk@
VY4yS*y
/** ?N9uu4
* @param totalPage Z@!+v19^
* The totalPage to set. %dVZ0dl
*/ d\8l`Krs[_
publicvoid setTotalPage(int totalPage){ htF] W|z
this.totalPage = totalPage; <>rneHl8
} E ~<JC"]
Qp3_f8
} )Ql%r?(F+
2c*GuF9(0
3f{3NzN
&V/MmmT
8{sGNCvU
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 vl:KF7:#m
uKHxe~
个PageUtil,负责对Page对象进行构造: zK@@p+n_#.
java代码: yY q,*<G
h2d(?vOT
0 @oJFJrO
/*Created on 2005-4-14*/ $xN|5;+
package org.flyware.util.page; }5"u[Z.
X'iWJ8
import org.apache.commons.logging.Log; }BP;1y6-r
import org.apache.commons.logging.LogFactory; <)D$51 &0
Ysv"
6b}
/** }qD\0+`qi
* @author Joa N(yzk_~
* S)@j6(HC4
*/ A*BeR0(
publicclass PageUtil { sfl<qD+?
WH^%:4
privatestaticfinal Log logger = LogFactory.getLog TM%%O :3
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(PageUtil.class); Qo|\-y-#
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/** u>vL/nI
* Use the origin page to create a new page ;RlxD 4p
* @param page j#4kY R{
* @param totalRecords |2A:eI8 ^
* @return [Y `W
*/ $[ *w"iQ
publicstatic Page createPage(Page page, int 4 #Jg9o
YN5rml'-
totalRecords){ x]j W<A
return createPage(page.getEveryPage(), 2GG2jky{/
}^\oCR@
page.getCurrentPage(), totalRecords); 6ik$B
} v`T
c}c '
CAf6:^0
/** J<lW<:!3]
* the basic page utils not including exception M"L=L5OH-
CTmT@A{
handler ~"A0Rs=
* @param everyPage Q/Rqa5LI:
* @param currentPage :Hbv)tS\3w
* @param totalRecords Q,Eo mt
* @return page -yg7;ff
*/ t6t!t*jO
publicstatic Page createPage(int everyPage, int 3OB"#Ap8<
\OoWo
currentPage, int totalRecords){ .6J$,.Ig
everyPage = getEveryPage(everyPage); x?<FJ"8"k
currentPage = getCurrentPage(currentPage); [#iz/q~}
int beginIndex = getBeginIndex(everyPage, 0n'_{\yz
'5tCz9}Y
currentPage); \b>]8Un"
int totalPage = getTotalPage(everyPage, CvdN"k
$:^td/p J
totalRecords); bI`g|v
boolean hasNextPage = hasNextPage(currentPage, !5N.B|Nt
+w~oH =
totalPage); _e2=ado
boolean hasPrePage = hasPrePage(currentPage); }QmqoCAE~m
hqdDm
returnnew Page(hasPrePage, hasNextPage, E*lxVua
everyPage, totalPage, 1.>m@Slr>
currentPage, rZpXPI
1E$|~
beginIndex); *NQ/UXE
} R|Q?KCI&
p]"4#q\(
privatestaticint getEveryPage(int everyPage){ oL<St$1
return everyPage == 0 ? 10 : everyPage; yDh6KUK
} `0R./|bv\I
AOx[
privatestaticint getCurrentPage(int currentPage){ 6MI8zRX
return currentPage == 0 ? 1 : currentPage; @j/&m]6%-D
} }PpUAt~g
z?//rXuO
privatestaticint getBeginIndex(int everyPage, int `F6C-
BJ0?kX@
currentPage){ 4GM6)"#d
return(currentPage - 1) * everyPage; _vZOZKS+
} hv+zGID7
R}ecc
privatestaticint getTotalPage(int everyPage, int :@&/kyGH
Xm&L
BX
totalRecords){ c`Wa^(
int totalPage = 0; l;V173W=&
.|=\z9_7S8
if(totalRecords % everyPage == 0) \j.:3Xr
totalPage = totalRecords / everyPage; rLT!To
else ctV,Q3'Z
totalPage = totalRecords / everyPage + 1 ; jFb?b6b
9>$p
return totalPage; q'11^V!0
} ET >](l9
:H[6Lg\*
privatestaticboolean hasPrePage(int currentPage){ {: W$LWET
return currentPage == 1 ? false : true; ~;] d"'
} F5#YOck&,
8$|=P!7EO
privatestaticboolean hasNextPage(int currentPage, D#z:()VT(
tI{_y
int totalPage){ IM+o.@f-
return currentPage == totalPage || totalPage == y3ikWnx
A(N4N
0 ? false : true; 9C i-v/M]
} cS+>J@L
E!AE4B1bd
S@sO;-^+
} kNL\m[W8$
iyog`s c
RrgGEx
{BHO/q3
t0I{q0
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]9,;K;1<
b u"!jHPB
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 D
sWSGb
1i] ^{;]
做法如下: bJ;'`sw1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,?XCyHSgWW
i 3SHg\~Z
的信息,和一个结果集List: (4EI-e*6
java代码: 8JD,u
RX5dO%
[c06 N$:
/*Created on 2005-6-13*/ v9->nVc-
package com.adt.bo; rXU\
I`p;F!s
import java.util.List; C'X!\}f.b/
Z(!\%mn
import org.flyware.util.page.Page; &!
?eL
!v0LBe4
/** ofv)SCjd
* @author Joa 8&aq/4:q0
*/ vZoaT|3
G]
publicclass Result { -D$8
"w.3Q96r
private Page page; xZv#Es%#
YUIi;
private List content; VU d\QR-
I
2|Bg,e
/** {Dmjm{
* The default constructor 1y4
*/ Ez=Olbk
public Result(){ J9[r|`gJ(
super(); `^y7f
} xK\d4"
'X2POay1
/** u-5{U-^_
* The constructor using fields Q)[C?obd v
* <3hRyG@vB
* @param page N'`A?&2ru
* @param content ilx)*Y
*/ qeZ? 7#Gf
public Result(Page page, List content){ 5N&?KA-
this.page = page; \)?HJ
this.content = content; fsWTF<Y
} p"ZG%Ow5Q]
X(-4<B
/** 7s{GbU\
* @return Returns the content. e;}7G
*/ 1^(ad;BCy
publicList getContent(){ 5, 6"&vU,
return content; }d}Ke_Q0
} [^98fAlz6
xx%j.zDI]
/** ^qD$z=z-
* @return Returns the page. (c
&mCJN
*/ -:y,N
9^
public Page getPage(){ ByNn
return page; JHTSUq
} Vt&2z)Zz
Y^EcQzLw
/** wyO4Y
* @param content orMwAV
* The content to set. D!-g&HBTC
*/ )ea>%
public void setContent(List content){ [;),\\u,d
this.content = content; PKg@[<g43
} *]/zc1Q4M
%.-4!vj
/**
MC.)2B7
* @param page #-i>;Rt
* The page to set. B; h"lv
*/ ~^fZx5
publicvoid setPage(Page page){ pm0{R[:T7
this.page = page; (b-MMr
} ;dZZ;#k%
} .Una+Z
!1H# 6
W^LY'ypT
c"V"zg22
.p]RKS=(:
2. 编写业务逻辑接口,并实现它(UserManager, RF4vtQC=
']z{{UNUN
UserManagerImpl) {~"/Y@&]R
java代码: 4`]^@"{
!_D0vI;
VfC <WVYiZ
/*Created on 2005-7-15*/ H-*yh!
package com.adt.service; ]]9R mh=
<~'"<HwtK
import net.sf.hibernate.HibernateException; s.N/2F&*W
suiS&$-E
import org.flyware.util.page.Page; 1
A
!bE
Z=Y& B>:[
import com.adt.bo.Result; YPK(be_|I
u9GQU
/** m6&~HfwN
* @author Joa %wvdn
*/ u4F5h PO]
publicinterface UserManager { lC("y'
::
e~[/i\
public Result listUser(Page page)throws (X1e5j>Ru
#9}D4i.`}
HibernateException; |w1Bq
_j/<{vS y
} wb5baY9
AFDq}*2Qb
m=A(NKZ
K'Tm_"[u
](9Xvy
java代码: >WQMqQ^t@
z/WE,R
)=Z>#iH1
/*Created on 2005-7-15*/ YY((V@|K
package com.adt.service.impl; +N9X/QFKV
_jI,)sr4ic
import java.util.List; T/Gz94c
v/0QOp
import net.sf.hibernate.HibernateException; %C'?@,7C
?'Xj
g#}<
import org.flyware.util.page.Page; Vb4#,
import org.flyware.util.page.PageUtil; U;V7 u/{
)}]g]
g
import com.adt.bo.Result; X_ cV%#
import com.adt.dao.UserDAO; gsvuE
import com.adt.exception.ObjectNotFoundException; q J=~Y|(
import com.adt.service.UserManager; ?(y*nD[a
HU}7zK2
/** 1N^[.=
* @author Joa *,)Md[
*/ @ ZwvBH
publicclass UserManagerImpl implements UserManager { `PdQX.wN
*vN-Vb^2i)
private UserDAO userDAO; *{@Nq=fE
RtP2]O(F
/** ;|5F[
* @param userDAO The userDAO to set. 2c,9e`
*/ Eh;'S"{/?j
publicvoid setUserDAO(UserDAO userDAO){ Gg3,:A_ w
this.userDAO = userDAO; SSg8}m5)Q
} Co_A/
-M~:lK]n
/* (non-Javadoc) -.@r#d/
* @see com.adt.service.UserManager#listUser kr5">"7
y8Z_Itlf
(org.flyware.util.page.Page) qu6D 5t
*/ cAqLE\h
public Result listUser(Page page)throws Nw/ ku
E`0?
HibernateException, ObjectNotFoundException { | '8Nh
int totalRecords = userDAO.getUserCount(); ]z;I_-
if(totalRecords == 0) )?naN
throw new ObjectNotFoundException 4qbBc1,7y
]G=L=D^cK
("userNotExist"); kT66;Y[
page = PageUtil.createPage(page, totalRecords); V`d,qn)i
List users = userDAO.getUserByPage(page); gHEu/8E
returnnew Result(page, users); VUGmi]qd
} o.g V4%
m@F`!qY~Y\
} n)e
6>R;
d-ZJL6-
YQ)kRhFA
-1_)LO&H
]BZA:dd.G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 x7w4[QYw
6qpJUkd
询,接下来编写UserDAO的代码: t?&|8SId
3. UserDAO 和 UserDAOImpl:
6f>{"'
java代码: :T$|bc
2'\H\|
Zw9FJ/Zn@
/*Created on 2005-7-15*/ 1~`fVg
package com.adt.dao; Rz/gtEP
\<>ih)J@tt
import java.util.List; {.|CdqwY
^_W#+>&--
import org.flyware.util.page.Page; J#(LlCs?@c
({)+3]x
import net.sf.hibernate.HibernateException; (Q!}9K3
RnE4<Cy
/** jo@6?(
*4
* @author Joa : /N0!&7
*/ ,WYPU
publicinterface UserDAO extends BaseDAO { L,`LN>
5` ~JPt
publicList getUserByName(String name)throws 'ya{9EdlT
@%uUiP0
HibernateException; (OL4Ex' ]
Bahm]2
publicint getUserCount()throws HibernateException; ,V m
< rK
hEH?[>9
publicList getUserByPage(Page page)throws b3[!V{|
69NeQ$](
HibernateException; Y=I'czg
Tv=mgH=b
} n'LrQU
gPO}d
>T-u~i$s
-f^tE,-
b\!_cb~ "@
java代码: ie95rZp
o#Dk&
cH
"Gzz4D
/*Created on 2005-7-15*/ ZvX*t)VjTz
package com.adt.dao.impl; 8/cX]J
i9|Sa6vuI
import java.util.List; BwpqNQN
9;u@q%;!k
import org.flyware.util.page.Page; RSRS wkC
|SSSH
import net.sf.hibernate.HibernateException; V)k4:H
import net.sf.hibernate.Query; rXP,\ ]r+
lrE5^;/s1
import com.adt.dao.UserDAO; 3;9^
gz9j&W.
/** K@]4g49A/j
* @author Joa `/+>a8
*/ u
c)eil
public class UserDAOImpl extends BaseDAOHibernateImpl Gb6 'n$g
`$9x 1dx
implements UserDAO { i&fuSk EP
t{9GVLZ
/* (non-Javadoc) $%d*@'c
* @see com.adt.dao.UserDAO#getUserByName t=iIY`Md%
PFjL1=7I
(java.lang.String) 9.-S(ZO
*/ $a]`nLUa
publicList getUserByName(String name)throws !f[_+CD
6d}lw6L
HibernateException { Bsvr?|L\
String querySentence = "FROM user in class q3!bky\
#trK^(
com.adt.po.User WHERE user.name=:name"; Rhs/3O8k
Query query = getSession().createQuery
UI0VtR]
FW4<5~'
(querySentence); $s:aW^k
query.setParameter("name", name); p6V0`5@t
return query.list(); @":
^)87
} =dKtV.L
%tGO?JMkd
/* (non-Javadoc) r#a=@
* @see com.adt.dao.UserDAO#getUserCount() x 9fip-
*/
=:pJ
publicint getUserCount()throws HibernateException {
v!5 `|\
int count = 0; I\ob7X'Xu!
String querySentence = "SELECT count(*) FROM NXrlk
~$^XP.a.
user in class com.adt.po.User"; &h/Xku&0
Query query = getSession().createQuery DTL.Bsc-.
Z FL~;_r
(querySentence); q 2E_A
count = ((Integer)query.iterate().next wmLs/:~
sO@Tf\d
()).intValue(); Q;rX;p^W
return count; ~]2K^bh8&
} f-Z/tfC
}|=|s f
/* (non-Javadoc) b\2
ds,
* @see com.adt.dao.UserDAO#getUserByPage 5.GR1kl6
b>ySv
(org.flyware.util.page.Page) L!xi
*/ _t^&Ah*
publicList getUserByPage(Page page)throws ?Ir:g=RP*
|+9&rAg
HibernateException { i/Zd8+.n$
String querySentence = "FROM user in class (4nq>;$3
cvL;3jRo
com.adt.po.User"; 0g8NHkM:2a
Query query = getSession().createQuery %pCTN P
+ZP7{%
(querySentence); eHUOU>&P]
query.setFirstResult(page.getBeginIndex()) Mo|2}nf
.setMaxResults(page.getEveryPage()); Z%UP6%
return query.list(); m8[j #=h
} h<QY5=SF
9\(|
D#
} QMm%@zH
iy.\=Cs$N
J{G?-+`
F#E3q|Q"BS
{'H(g[k
至此,一个完整的分页程序完成。前台的只需要调用 y@yD5$/
aN3;`~{9
userManager.listUser(page)即可得到一个Page对象和结果集对象 HZZn'u
+=)+'q]S
的综合体,而传入的参数page对象则可以由前台传入,如果用 YS_;OFsd
"m>81-0
webwork,甚至可以直接在配置文件中指定。 *LY8D<:zs
1o>xEWt:0K
下面给出一个webwork调用示例: xT2PyI_:
java代码: tZo} ;|~'
G3v5KmT
(pM5B8U
/*Created on 2005-6-17*/ MMCac6;Aea
package com.adt.action.user; $3>k/*=
3a PCi>i!_
import java.util.List; v#*9rNEj0
wY|&qX,
import org.apache.commons.logging.Log; $z,lq#zzl
import org.apache.commons.logging.LogFactory; z=1 J{]
import org.flyware.util.page.Page; 5=%:CN!/@p
MMg"G6?
import com.adt.bo.Result; *y[i~{7:
import com.adt.service.UserService; ?"f\"N
import com.opensymphony.xwork.Action; *izPLM}+
K] ;`
/** QA?e2kd
* @author Joa WLGk
*/ T0BFit6
publicclass ListUser implementsAction{ SA_5..
7U68|\fI!
privatestaticfinal Log logger = LogFactory.getLog Q\>9PKK
eh_{-
(ListUser.class); 55xaZ#|
:*|%g
private UserService userService; {n9]ej^
y ,][
private Page page; w$I<WS{J:Z
E>|[@Z
privateList users; 1L722I@
! bbVa/
/* USF&; M3
* (non-Javadoc) d*3;6ZLy
* 1_JtD|Jy
* @see com.opensymphony.xwork.Action#execute() } :U'aa
*/ L=Cm0q 3v
publicString execute()throwsException{ y4* }E
Result result = userService.listUser(page); dXr=&@1
page = result.getPage(); =#)Zm?[;
users = result.getContent(); <P&~k\BuF{
return SUCCESS; E__^>=
} s5{N+O)~S
(p4|,\+
/** \uxDMKy
* @return Returns the page. b0W~*s [4
*/ lq0@)'D
public Page getPage(){ y\-f{I
return page; AQX~do\A
} tXj28sh$
-*q:B[d
/** _@U?;73"5
* @return Returns the users. :N!Fe7H,
*/ Y:|_M3&'o
publicList getUsers(){ {2u#Q7]|
return users; #1-y[w/
} 1J$sIY,Ou
a<AT;Tc
/** RmXC
^VQ
* @param page l :sZ
* The page to set. RU}
M&&
*/ :e9}k5kdk
publicvoid setPage(Page page){ -]8cw#y
0A
this.page = page; AhjK*nJF
} 1J8okBhZ
MQD%m ;[s
/** ;dXQB>Za
* @param users GLI 5AbQK
* The users to set. 5sbMp;ZM
*/ S`,(10Y
publicvoid setUsers(List users){ HJFt{tq2
this.users = users; 5nq0#0Oc
} 7:fC,2+
F$TNYZ
/** u\~dsD2)q
* @param userService om$x;L6
* The userService to set. A`E7V}~
*/ 88 fH!6b
publicvoid setUserService(UserService userService){ pJM~'tlHV
this.userService = userService; U`gQ7
} LKtug>Me
} .
J"g.Q
_g+^ jR4
;;z4EGr
>)g`;iO
|eD$eZ=m
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, xyGk\= S
;XFo:?
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 d\FBY&C7b
CA2 ,
么只需要: 0IHcyb
java代码: !Pnvqgp/
y,$kU1yH7
yya"*]*S
<?xml version="1.0"?> 0(A(Vb5J.T
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork S1 22.
I
XA`<*QC<
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ICSi<V[y1
w6C0]vh
1.0.dtd"> *b+ef
x5q5<-#
<xwork> 6?-vj2,
fVCpG~&t
<package name="user" extends="webwork- g~FA:R
&WW|! 6
interceptors"> ]Bo !v*12
|2mm@):
<!-- The default interceptor stack name JTu^p]os?
PprCz"
--> NP%Y\%;l6
<default-interceptor-ref _8$arjx=
#DMt<1#:
name="myDefaultWebStack"/> Y\!* c=@k
f?O?2g
<action name="listUser" zcCX;N
>;Er[Rywr
class="com.adt.action.user.ListUser"> #K1VPezN
<param 1#H=<iJ
2CX'J8Sy
name="page.everyPage">10</param> T_}9b
<result wfH#E2+pk
Bob K>db
name="success">/user/user_list.jsp</result> Y#3<w
</action> 8^26g3
N%Gb
</package> 2y6 e]D
{[V<mT2/
</xwork> Kj|l]'
XV"8R"u%Q
$RxS<_tj
@ i$jyc
Bi7QYi/
QKW;r
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 m22FOjk\
p8CDFLuV
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。 LF\4>(C2g
37Z@a!#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 tz#Fy?pe
&)4#0L4
BeAkG_uG
b}DxD1*nsI
9r,)Bw!RP
我写的一个用于分页的类,用了泛型了,hoho $j?zEz
'1|FqQ\.
java代码: X
wvH
?7Kl)p3
=+{SZh@
package com.intokr.util; XcfvmlBoD-
neN #Mo'A
import java.util.List;
Gw4~
]3B8D<p
/** Gt>*y.]
* 用于分页的类<br> ifyWhS++
* 可以用于传递查询的结果也可以用于传送查询的参数<br> l423+vo
* mUFg(;ya
* @version 0.01 wjLtLtK?
* @author cheng 8|FHr,
*/ s];jroW@u
public class Paginator<E> { |$AoI
privateint count = 0; // 总记录数 #9Src\V
privateint p = 1; // 页编号 vUtA@
privateint num = 20; // 每页的记录数 qX,TX
3
privateList<E> results = null; // 结果 ozF173iI
Yz6+
x]
/** >"}z
% #
* 结果总数 "n,?)
*/ IdP"]Sv{<
publicint getCount(){ Jat|n97$
return count; bq+Q$#F2X
} t|/{oAj
>M `ryM2=D
publicvoid setCount(int count){ xA?(n!{P
this.count = count; =\[}@Kh
} H_ecb;|mP
ak_&\'P
/** 25bLU?x5B
* 本结果所在的页码,从1开始 >St]MS
* ?+^vU5b1u
* @return Returns the pageNo. `dp]N0nz
*/ 8v|?g8e3
publicint getP(){ +;@p'af!9
return p; $0(~ID
} .=I:cniw\r
xna4W|-
/** Aw7oyC!
* if(p<=0) p=1 !:zWhu,
* 3Gr:.V9=
* @param p @d/Wa=K
*/ Ug2^cgL
publicvoid setP(int p){ .|Ee,Un
if(p <= 0) RWfC2$z
p = 1; 295U<
this.p = p; ysHmi{V~
} U/p|X)
j B.ZF7q
/** dc]D 8KX
* 每页记录数量 L5wrc4
*/ R=/^5DZ}
publicint getNum(){ ]&oQ6
return num; ` D9sEt_/
} ,.Sd)JB'
\R}`S`fIw`
/** v&#=1Zb
* if(num<1) num=1 }\-"L/D?+
*/ K4.GAGd
publicvoid setNum(int num){ $>Mqo
if(num < 1) ~WKcO&
num = 1; H.H$5(?O
this.num = num; D
on8xk
} 6Z:swgi6&
`8D)j>Yh~
/** 'K8emt$d+
* 获得总页数 _7k6hVQ
*/ K]bw1KK
publicint getPageNum(){ })Pq!u:3
return(count - 1) / num + 1; s{30#^1R
} |K7zN\
Wq
$@R[$/
/** l7p*::(9
* 获得本页的开始编号,为 (p-1)*num+1 '9w.~@7
*/ 4!3mS WNV
publicint getStart(){ Y*KHr`\C4
return(p - 1) * num + 1; `g~T #U\>d
} 4/Wqeq,E8
.&Q'aOg
/** ;OTd<
* @return Returns the results. L{i,.aE/nO
*/ >&`S$1 o
publicList<E> getResults(){ BY&+fKae
return results; jQ 'r};;
} .dr-I7&!
GK>. R<[
public void setResults(List<E> results){ `'gadCTb=
this.results = results; HK/T`p#
} ^rP`
.Z
<q dM
public String toString(){ 2y"|l
StringBuilder buff = new StringBuilder Vw P+tM
8rXQK|A
(); P%nN#Qm
buff.append("{"); DNu^4#r
buff.append("count:").append(count); #+<"`}]N
buff.append(",p:").append(p); jJ B+UF=
buff.append(",nump:").append(num); b-Q%cxJ
buff.append(",results:").append [*jvvkAp
>w}5\4j
(results); g`690
buff.append("}"); pod=|(c
return buff.toString(); ._$tNGI4
} V7pe|]%r
=D@+_7\?
} m&36$>r=
ZWVN(U
7[)IP:I>