Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 D/Py?<n-B
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /sdZf|Zl
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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 @jKB[S;JSn
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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 #j)"#1IE2W
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分页支持类: wv^n#
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java代码: k&17 (Tv$
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package com.javaeye.common.util; *NC@o*
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import java.util.List; 0e1-ZP CDj
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publicclass PaginationSupport { #\\|:`YV
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publicfinalstaticint PAGESIZE = 30; w1eFm:'
*q+X?3
privateint pageSize = PAGESIZE; G=|~SYz
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privateList items; LL==2KNUo
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privateint totalCount; 1x%B`d
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privateint[] indexes = newint[0]; bAwKmk9C
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privateint startIndex = 0; qw{`?1[+
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public PaginationSupport(List items, int B<0Kl.V
7VL|\^Y `q
totalCount){ E;[Uhh|78!
setPageSize(PAGESIZE); Qxk & J
setTotalCount(totalCount); A0:rn\$l3
setItems(items); B9Hib1<8
setStartIndex(0); N1B$z3E*
} 9zY6hh**
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public PaginationSupport(List items, int w 5?D]u
#'0Yzh]qc
totalCount, int startIndex){ 2_y]MXG+%
setPageSize(PAGESIZE); ambr}+}
setTotalCount(totalCount); A\#z<h[>
setItems(items); D~#%^a+Aq_
setStartIndex(startIndex); 57-Hx;
} 2TNK
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public PaginationSupport(List items, int _^NyLI%
zo8D"
totalCount, int pageSize, int startIndex){ Id&e'
setPageSize(pageSize); Fk^N7EJ:$
setTotalCount(totalCount); 0^sY>N"
setItems(items); o]RZd--c<
setStartIndex(startIndex); ^'a#FbMtt
} Gx6%Z$2n
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publicList getItems(){ Cs7ol-\)
return items; R TpNxr{[
} .7
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publicvoid setItems(List items){ YO$D-
this.items = items; <|jh3Hlp
} rM"27ud[`_
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publicint getPageSize(){ 6#!CBY^{
return pageSize; 5l
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} 6{Q-]LOc[.
V`1{*PrI@L
publicvoid setPageSize(int pageSize){ bXOKC
this.pageSize = pageSize; ^n(FO,8c
} FV/t
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publicint getTotalCount(){ >Vjn]V5y
return totalCount; kuD$]A
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} HFZ'xp|3dn
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publicvoid setTotalCount(int totalCount){ $_E.D>5^%7
if(totalCount > 0){ abQ.N
this.totalCount = totalCount; wW1VOj=6V"
int count = totalCount / l|?tqCT ^h
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pageSize; M7cD!s@'I
if(totalCount % pageSize > 0) c
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count++; ou <3}g
indexes = newint[count]; uBx\xeI
for(int i = 0; i < count; i++){
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indexes = pageSize * L)J1yw
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} J
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}else{ ;v@ G
this.totalCount = 0; ~3?-l/ $
} t.28IHJ
} hbH~Ya=+S
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publicint[] getIndexes(){ IDH~nMz
return indexes; >X$JeME3
} 7qB4_
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publicvoid setIndexes(int[] indexes){ KHML!f=mu
this.indexes = indexes; z/1$G"
} m7'<k1#"Y
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publicint getStartIndex(){ B@&sG
5ES
return startIndex; g8##Be
} "CJ~BJI%
@./h$]6
publicvoid setStartIndex(int startIndex){ 4=([v;fc
if(totalCount <= 0) 6e+'Y"v
this.startIndex = 0; <u!cdYo@
elseif(startIndex >= totalCount) U"k$qZ[
this.startIndex = indexes )y,^M3$?C
,IjZQ53q~
[indexes.length - 1]; $ZBYOA
elseif(startIndex < 0) VV$t*9w
this.startIndex = 0; <giBL L!
else{ gm-[x5O"
this.startIndex = indexes .xsfq*3e5
}L_YpG7
[startIndex / pageSize]; <=*f
} .HS6DOQ
} M/?,Qii
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publicint getNextIndex(){ e3p|g]
int nextIndex = getStartIndex() + ODxZO3
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pageSize; f jx`|MJ
if(nextIndex >= totalCount) I%3[aBz4
return getStartIndex(); j,k3]bP
else m-Eh0Zl>Z
return nextIndex; MUrPr
} Al-`}g+^
cV+?j}"*+
publicint getPreviousIndex(){ MET9rT
int previousIndex = getStartIndex() - oACAC+CP
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pageSize; R /+$ :
if(previousIndex < 0) $v0,)AL i
return0; /|0-O''
else QKG3>lU
return previousIndex; %k!CjW3
} KNVu[P)rv
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} <u64)8'
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抽象业务类 AFrJzh:V[
java代码: .IeO+RDQ
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/** _'=,c"
* Created on 2005-7-12 C96/
*/ IO%kXF.[
package com.javaeye.common.business; jeC=s~
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import java.io.Serializable; RzEzNV
import java.util.List; 5n@YNaoIb
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import org.hibernate.Criteria; `/8@Fj
import org.hibernate.HibernateException; q/i2o[f'n
import org.hibernate.Session; 6D;N.wDZ
import org.hibernate.criterion.DetachedCriteria; >US*7m }
import org.hibernate.criterion.Projections; #HUn~r
import xcB\Y:
DR#" 3
org.springframework.orm.hibernate3.HibernateCallback; hG1:E:}
import qN!oN*
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org.springframework.orm.hibernate3.support.HibernateDaoS 1!#N-^qk
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upport; &uq.k{<p\
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import com.javaeye.common.util.PaginationSupport; tB_le>rhl
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public abstract class AbstractManager extends /$~1e7W
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HibernateDaoSupport { (5yM%H8:
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privateboolean cacheQueries = false; ;+Jx,{)
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privateString queryCacheRegion; &o:5lxR{
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publicvoid setCacheQueries(boolean ;blL\|ch;
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cacheQueries){ ({uW-%
this.cacheQueries = cacheQueries; 8g#$Y2P
} _7c3=f83
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publicvoid setQueryCacheRegion(String iE%" Q? Q/
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queryCacheRegion){ {[y6qQm
this.queryCacheRegion = g4?2'G5m?
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queryCacheRegion; |XyX%5p*
} %>|FJ
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publicvoid save(finalObject entity){ 2#wnJdr6E
getHibernateTemplate().save(entity); c{q+h V=
} (.J/Ql0Y
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publicvoid persist(finalObject entity){ J
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getHibernateTemplate().save(entity); yV^Yp=f_
} eg[EFI.h
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publicvoid update(finalObject entity){ QkrQM&Im
getHibernateTemplate().update(entity); 8Pn
} ni;_Un~
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); 66=[6U9 *
} AL]gK)R
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publicObject load(finalClass entity, JPI%{@Qc^
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finalSerializable id){ ETDWG_H |
return getHibernateTemplate().load kWzp*<lWe
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(entity, id); u8f\)m
} |Ajd$+3
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publicObject get(finalClass entity, 9q;O`&
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finalSerializable id){ *i"9D:
return getHibernateTemplate().get z{XB_j6\=
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(entity, id); o "z()w~
} 91R#/i
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publicList findAll(finalClass entity){ vC]X>P5 Px
return getHibernateTemplate().find("from M9"Bx/
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" + entity.getName()); d)
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} wNa5qp
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publicList findByNamedQuery(finalString ?P9aXwc
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namedQuery){ 1RAkqw<E
return getHibernateTemplate H/a gt
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().findByNamedQuery(namedQuery); 6wlLE5
} '54\!yQ<{
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publicList findByNamedQuery(finalString query, #`Su3~T=S
& SXw=;B
finalObject parameter){ tZ]gVgZg
return getHibernateTemplate O-,
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().findByNamedQuery(query, parameter); :82T!
} <H-Nft>O
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publicList findByNamedQuery(finalString query, 3lF"nv
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finalObject[] parameters){ juEPUsE
return getHibernateTemplate n/9afIN
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().findByNamedQuery(query, parameters); Jv}
} _H$Lu4b)N
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publicList find(finalString query){ w =GMQ8
return getHibernateTemplate().find lY,^
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(query); N,Y)'s<
} $PJ==N
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publicList find(finalString query, finalObject < $zJi V
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parameter){ 5>}$]d/o
return getHibernateTemplate().find 8maWF.xq
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(query, parameter); JM7mQ'`Ud
} TpU\IQ
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public PaginationSupport findPageByCriteria ^s)`UZ<C=
;!<}oZp{
(final DetachedCriteria detachedCriteria){ ;21D ^e
return findPageByCriteria ?V6,>e_+
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); R"W}\0k
} `7/(sX.
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public PaginationSupport findPageByCriteria =:rg1wo"c
d:)#-x*h7
(final DetachedCriteria detachedCriteria, finalint f|{iW E2d
dlYpbw}W&<
startIndex){ fo ~uI(rk
return findPageByCriteria %]+R>+
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(detachedCriteria, PaginationSupport.PAGESIZE, J?O0ixU
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startIndex); R XCn;nM4
} d{YvdN9d
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public PaginationSupport findPageByCriteria HLWffO/
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(final DetachedCriteria detachedCriteria, finalint Z"8lW+r*
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pageSize, :a }](Wn
finalint startIndex){ ;wwc;wQ'
return(PaginationSupport) /p
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getHibernateTemplate().execute(new HibernateCallback(){ ) H,Xkex
publicObject doInHibernate ~nA k-toJ
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(Session session)throws HibernateException { re*}a)iL
Criteria criteria = s|\)Y*B`
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detachedCriteria.getExecutableCriteria(session); _,drOF|e
int totalCount = W %*#rcdq
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((Integer) criteria.setProjection(Projections.rowCount nXT`7
_ $a3lR
()).uniqueResult()).intValue(); +4 k=Y
criteria.setProjection 0GUJc}fgvN
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(null); t'U=K>7
List items = lE k@I"
av'm$I|O
criteria.setFirstResult(startIndex).setMaxResults :9hGL
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(pageSize).list(); ${T/b(NM
PaginationSupport ps = \OW:-
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new PaginationSupport(items, totalCount, pageSize, .I^4Fc}&4
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startIndex); 70qEqNoC
return ps; fOi
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} j!4{+&Laq
}, true); SW9
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} ^5X?WA,Z99
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public List findAllByCriteria(final u
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DetachedCriteria detachedCriteria){ <H^jbK
return(List) getHibernateTemplate 72;'8
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().execute(new HibernateCallback(){ w'TAM"D`
publicObject doInHibernate ~:Rbd9IB
) ^En
(Session session)throws HibernateException { $9YQ aN%
Criteria criteria = boojq{cvYA
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detachedCriteria.getExecutableCriteria(session); 5M>h[Q"R
return criteria.list(); {]\7
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} pN^g.
}, true); wh(_<VZ
} nL?P/ \
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public int getCountByCriteria(final |"}rdOV)
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DetachedCriteria detachedCriteria){ AGFA;X
Integer count = (Integer) $+80V{J#
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getHibernateTemplate().execute(new HibernateCallback(){ ,8384'
publicObject doInHibernate :aOR@])>o
! t!4CY
(Session session)throws HibernateException { i"V.$|,
Criteria criteria = 8-<F4^i_i
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detachedCriteria.getExecutableCriteria(session); ?;RY/[IX6
return &>AwG4HW#j
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criteria.setProjection(Projections.rowCount ug,AvHEnB
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()).uniqueResult(); ]0>
} N5K(yY_T
}, true); ;?{^LiD+F
return count.intValue(); +[
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} - ;gQy[U
} JLm3qIC
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用户在web层构造查询条件detachedCriteria,和可选的 F9LKO3Rh#u
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 yhgGvyD
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PaginationSupport的实例ps。 2D%2k
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ps.getItems()得到已分页好的结果集 x"Ll/E)\v]
ps.getIndexes()得到分页索引的数组 mW]dhY 3X
ps.getTotalCount()得到总结果数 8{0XqE~ix=
ps.getStartIndex()当前分页索引 /
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ps.getNextIndex()下一页索引 8\;, d
ps.getPreviousIndex()上一页索引 lrc%GU):
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #qVvh3#g
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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 #NyO'
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一下代码重构了。 bCP2_h3*
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我把原本我的做法也提供出来供大家讨论吧: {
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首先,为了实现分页查询,我封装了一个Page类: 78]*Jx>L
java代码: 9q0s
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/*Created on 2005-4-14*/ Ib{#dhV
package org.flyware.util.page; 3KqRw (BK
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/** cL .z{
* @author Joa EyR/
* gWjYS#D
*/ >4bw4
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publicclass Page { (soTkH:#
s8A"x`5(
/** imply if the page has previous page */ 851BOkRal4
privateboolean hasPrePage; (8~mf$ zx,
bkR~>F]FAu
/** imply if the page has next page */ 8=bn
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privateboolean hasNextPage; &b~X&{3,
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/** the number of every page */ pno}`Cer
privateint everyPage; DNDzK
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/** the total page number */ $C=XSuPNK
privateint totalPage; 1r4NP
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/** the number of current page */ '/D2d
privateint currentPage; e4_A`j'
o *U-.&
/** the begin index of the records by the current B]hRYU
/qKor;x
query */ <% mD#S
privateint beginIndex; Qd~7OH4Lp
vp&.
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/** The default constructor */ >8{{H"$;(
public Page(){ ^^k9Acd~p
X:f5t` ;
} |0p@'X1
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/** construct the page by everyPage nIlx?(=pu
* @param everyPage 6 ym$8^
* */ f"\klfrRI_
public Page(int everyPage){ e7n0=U0
this.everyPage = everyPage; }VWUcALJV
} (VkO[5j
4uE)*1
/** The whole constructor */ |gk4X%o6
public Page(boolean hasPrePage, boolean hasNextPage, uZf
6W<a
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int everyPage, int totalPage, ,. ht ~AE
int currentPage, int beginIndex){ Pdh`Gu1:3
this.hasPrePage = hasPrePage; #u"@q< )
this.hasNextPage = hasNextPage; 9%R"(X)
this.everyPage = everyPage; st.{AEv@
this.totalPage = totalPage; A3HNMz
this.currentPage = currentPage; "`S?q G
this.beginIndex = beginIndex; li{<F{7
} 04-@c
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/** f;+.j/ +
* @return lHliMBSc
* Returns the beginIndex. $6ucz'
*/ !z:j-gT3
publicint getBeginIndex(){ xe.f]a
return beginIndex; #5^OO ou|
} 03 iy[~Y2
+|<bb8%
/** 4QPHT#e qX
* @param beginIndex ]
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* The beginIndex to set. #;1RStb:zj
*/ ]A\qI>,
publicvoid setBeginIndex(int beginIndex){ _BgWy#
this.beginIndex = beginIndex; Mx# P
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} F}F{/
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/** 4__HH~j ?Q
* @return QiqRx
* Returns the currentPage. ;Hp78!#,
*/ -IDhK}C&T
publicint getCurrentPage(){ ZOppec1D
return currentPage; 7)> L#(N
} _ Fk^lDI-
q+;lxR5D
/** t82*rCIB{
* @param currentPage XCgC^c'
* The currentPage to set. y+7+({w<
*/ VsL*&Fk
publicvoid setCurrentPage(int currentPage){ ,#^2t_c/
this.currentPage = currentPage; RN&8dsreZp
} QD-Bt=S7l
}`2+`w%uZ
/** 8[
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* @return rc`I l{~k
* Returns the everyPage. iP9Dr<P
*/ hsK(09:J
publicint getEveryPage(){ R$it`0D4o
return everyPage; q}E'x/s2m
} ^g <Lu/5w
gxVJH'[V5
/** mEb`ET|
* @param everyPage _jVJkg)]
* The everyPage to set. M%!j\}2A
*/ daf-B-
publicvoid setEveryPage(int everyPage){ xi.QHKBZaH
this.everyPage = everyPage; q #8z%/~k
} UU#$Kt*frR
~ihi!u%~}
/** G he@m6|D
* @return ?]}=4
* Returns the hasNextPage. )%:
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*/ ((BdT:T\_
publicboolean getHasNextPage(){ n@oSLo`k,`
return hasNextPage; h`tf!M D]
} 0zjGL7
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/** X`]>J5
* @param hasNextPage
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* The hasNextPage to set. 'E\qqE[;
*/ +:J:S"G
publicvoid setHasNextPage(boolean hasNextPage){ H_l>L9/\
this.hasNextPage = hasNextPage; {#+'T 13sx
} "?Jf#
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/** $BOIa
* @return 7l'1
* Returns the hasPrePage. D6P/39}W
*/ ;tZ 8Sh)
publicboolean getHasPrePage(){ 7#g<fh
return hasPrePage; n+'s9
} Q0""wRq'
A&Q!W)=
/** b]WvKdq
* @param hasPrePage l-'\E6grdH
* The hasPrePage to set. Tz/[P:O3
*/ 1| xKb(_l
publicvoid setHasPrePage(boolean hasPrePage){ FJB
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this.hasPrePage = hasPrePage; &([Gc+"5E.
} >>>MTV f
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/** )Mw 3ZE92
* @return Returns the totalPage. k%LsjN.S
* NV3oJ0f&2
*/ 2\[
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publicint getTotalPage(){ e/IVZmUn^
return totalPage; wV{VV?h}
} Sr6?^>A@t
i]zTY\gw8M
/** 3>^S6h}o
* @param totalPage jTok1k
* The totalPage to set. /^[K
*/ A)f/ww)Q
publicvoid setTotalPage(int totalPage){ *18J$
this.totalPage = totalPage; S%w67sGl4n
} Q".p5(<
.@f)#2
} UeSPwY
2{)<Df@
S!~p/bB[+I
FHZQyO<|
l8N5}!N
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 O u{|o0
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个PageUtil,负责对Page对象进行构造: +D#.u^
java代码: ch0x*[N@
9QN(Wq@
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/*Created on 2005-4-14*/ <D(|}5qR
package org.flyware.util.page; LQa1p
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import org.apache.commons.logging.Log; a(+u"Kr
z
import org.apache.commons.logging.LogFactory; ; HjT
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/** <h1J+
* @author Joa [{rne2sA
*
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*/ LwEc*79
publicclass PageUtil { _1HEGX\
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privatestaticfinal Log logger = LogFactory.getLog l)91v"vJ
~DK=&hCd!
(PageUtil.class); LfG$?<}hR
Fk&A2C}$b
/** b]5S9^=LI
* Use the origin page to create a new page 2dBjc{
* @param page Ya,(J0l
* @param totalRecords [r=U-
* @return }{
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*/ M%FKg/
publicstatic Page createPage(Page page, int 3x~AaC.j
*Ja,3Qq
totalRecords){ 3})0p
return createPage(page.getEveryPage(), =?-
sazF&
"0l7%@z*)q
page.getCurrentPage(), totalRecords); u:O6MO9^
} qy~@cPT
v@E/?\k"
/** O(f&0h
!
* the basic page utils not including exception |m>n4-5QL
U})Z4>[bvt
handler ^Dhu8C(
* @param everyPage 7_ah1IEK
* @param currentPage DM@&=c
* @param totalRecords f@= lK?Pfh
* @return page 7u7 <"?v=
*/ Qz?r4kR
publicstatic Page createPage(int everyPage, int ;
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n`)wD~mk
currentPage, int totalRecords){ -}2e+DyAy
everyPage = getEveryPage(everyPage); #2*2xt
currentPage = getCurrentPage(currentPage); z@S39Xp==
int beginIndex = getBeginIndex(everyPage, A4uDuB;;ZQ
ZIrJ"*QO=
currentPage); j;b<oQH
int totalPage = getTotalPage(everyPage, ';bovh@*
pu*vFwZ
totalRecords); nob^
I5?
boolean hasNextPage = hasNextPage(currentPage, *!y.!v*
5U/1Z{
totalPage); r'ydjy
boolean hasPrePage = hasPrePage(currentPage); ]xIfgSq
35[8XD
returnnew Page(hasPrePage, hasNextPage, (^Kcyag4
everyPage, totalPage, t7p`A8&
currentPage, rpT{0>5
9v<Sng
beginIndex); cAE.I$T(
} e
r;3TG~
5CsJghTw
privatestaticint getEveryPage(int everyPage){ zz4A,XrD
return everyPage == 0 ? 10 : everyPage; =Gq
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} R]Q4+
d>Z{TFY
privatestaticint getCurrentPage(int currentPage){ q(yw,]h]{
return currentPage == 0 ? 1 : currentPage; \ns#l@B
} 1Bz'$u;
N|ut^X+|\
privatestaticint getBeginIndex(int everyPage, int ^Q?I8,4}
7^~pOFdH
currentPage){ h,V#V1>Hu
return(currentPage - 1) * everyPage; f9FsZD
} ?)cNe:KY
a]465FY
privatestaticint getTotalPage(int everyPage, int sS $- PX
C
snBC +`-
totalRecords){ |j
i}LWcD
int totalPage = 0; *s6MF{Ds
%Iv0<oU
if(totalRecords % everyPage == 0) (r^IW{IndX
totalPage = totalRecords / everyPage; WQ]~TGW
else )]%GNdU
totalPage = totalRecords / everyPage + 1 ; i%W,Y8\uf*
kl| KFdA;
return totalPage; h(I~HZ[K&T
} eP3)8QC
>=2nAv/(
privatestaticboolean hasPrePage(int currentPage){ _qmBPUx
return currentPage == 1 ? false : true; $+ZO{
(
} B\}E v&
~?6V-m{>#
privatestaticboolean hasNextPage(int currentPage, Uz H)fB
RN3w{^Ll
int totalPage){ i<1w*yu
return currentPage == totalPage || totalPage == tGd9Cs9D<
/Yx 1S'5
0 ? false : true; ;oULtQ
} eF}Q8]da
%I%F
!M
t_,iV9NrZ
} CQ"IL;y
f<WnPoV
&6MGPh7T
PKfxL}:"8
n`6 8<ybl5
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Sd^e!?bp
Cz?N[dhh
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 rQ*'2Zf'<
ss,t[`AV{
做法如下: 0} liK
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1w+&Y;d|
`-s+ zG
的信息,和一个结果集List: VrO$SmH
java代码: =t&B8+6
J`} /+WN 7
/ vje='[!
/*Created on 2005-6-13*/ GMgsM6.R
package com.adt.bo; 'iMI&?8u
)Ah
import java.util.List; WqY:XE+?\
<pYGcVB9V
import org.flyware.util.page.Page; ^lRXc.c z
^67P(h
/** A~nq4@uj
* @author Joa Xj+1]KRN
*/ ?*,N
?s(U
publicclass Result { $./JA)`
}%$9nq3
private Page page; kZ`60X%wE
$hn_4$
private List content; Lkk'y})/
+*)B;)P
/** %>xW_5;Z
* The default constructor _rs!6tp
*/ L V33vy
public Result(){ O%(:8nIgZ
super(); Gu*;z% b2
} X-oou'4<
79:x>i=
/** X@af[J[cQ
* The constructor using fields 09|d<
* kfm8F8sxl
* @param page R\0]\JEc
* @param content Ha)w*1&w"
*/ G*ym[
public Result(Page page, List content){ ?PyI#G
this.page = page; 4d0PW#97.
this.content = content; ttZ!P:H2
} }Ax$}#
,589/xTA@
/** ?$-OdABXHK
* @return Returns the content. 'OBAnE<.
*/ lP9a*>=a
publicList getContent(){ "-v9V7KCM
return content; _a15R/S
} #MGZje,I
us`hR!_
/**
@tDVW*!
* @return Returns the page. JO+ hD4L
*/ fB
public Page getPage(){ v8 6ls[lzu
return page; "-ZuH
} -k$rkKHZ(
sHQe0"Eo
/** En5I
* @param content hs<7(+a
* The content to set. ;\Wg>sq
*/ 8.Y6r
public void setContent(List content){ m&2<?a}l
this.content = content; KkAk(9Q/3
} Q$kSK+ q!
20% xD e
/** 8{Zgvqbb
* @param page %I6iXq#
* The page to set. J,{sRb%
*/ Rq4\~F?
publicvoid setPage(Page page){ *QjFrw3
this.page = page; '7xmj:.==
} O^U{I?gQ
} h"wXmAf4%
,a5I:V^\
*]x]U >EF
\:-; {
d['BtVJ
2. 编写业务逻辑接口,并实现它(UserManager, }4eSB
)W*S6}A
UserManagerImpl) GbStqR~^#
java代码: (MNbABZQ
J,+|
Fb
O]^E%;(]}i
/*Created on 2005-7-15*/ ^(UL$cQ>
package com.adt.service; K-p1v!IC
3(AgUq
import net.sf.hibernate.HibernateException; zbi[r
)ALf!E%{
import org.flyware.util.page.Page; 4V<s"
/o8h1L=
import com.adt.bo.Result; ]_F%{ 8|
s:;!QIC5jo
/** =<a`G3SY!
* @author Joa LA"`8
*/ 9Z
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publicinterface UserManager { (B,CL222x
=3/||b4c
public Result listUser(Page page)throws ~{U~9v^v(
ur*1I/v
HibernateException; ic?6p
3{]i| 1&j
} vxZz9+UbF
3Yg/-=U(
AP/5,M<
Tfs7SC8ta
XP6R$0yN
java代码: A*MlK"
]#R;%L
(j}"1
/*Created on 2005-7-15*/ e~nmIy
package com.adt.service.impl; #N@sJyIN
.T4"+FTzP
import java.util.List; -4;{QB?
;se-IDN
import net.sf.hibernate.HibernateException; . (Q;EF`_U
ihf5`mk/$
import org.flyware.util.page.Page; />K$_T/]
import org.flyware.util.page.PageUtil; IqcPml{\
c%Kv"Z%f
import com.adt.bo.Result; }c%QF
import com.adt.dao.UserDAO; jyLpe2 S
import com.adt.exception.ObjectNotFoundException; \W}?4kz
import com.adt.service.UserManager; Fgt/A#`fz
<iJ->$
/** b\dBt#mB!
* @author Joa @6}c\z@AxM
*/ YNHn# 98\
publicclass UserManagerImpl implements UserManager { 9'td}S
)uZ<?bkQ
private UserDAO userDAO; m:II<tv
@&mv4zz&W
/** $PHKI B(
* @param userDAO The userDAO to set. >L?/Ph %d
*/ YeYFPi#
publicvoid setUserDAO(UserDAO userDAO){ }oj$w?Ex
this.userDAO = userDAO; ^nFa'=
} 9V[|_
@H1pPr
/* (non-Javadoc) .nKyB'uV
* @see com.adt.service.UserManager#listUser I zM =?,`
G@
BrU q
(org.flyware.util.page.Page) DJ[U^dWRn
*/ KX[_eOL
public Result listUser(Page page)throws nPR_:_^
#B;` T[
HibernateException, ObjectNotFoundException { b ]1SuL
int totalRecords = userDAO.getUserCount(); OT{qb!eYI
if(totalRecords == 0) n"(n*Hf7b
throw new ObjectNotFoundException W>bhSKV%
zp,f}
("userNotExist"); c^Rz?2x
page = PageUtil.createPage(page, totalRecords); 'O
\YL(j_e
List users = userDAO.getUserByPage(page); ('OPW&fRG
returnnew Result(page, users); ^['% wA%
} k2,n:7
-gv@
.# N
} ]J5[ZVz
V-O 49
%4imlP
xJJlV P
Bwn9ZYu#r
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 EYcvD^!1g
xXp\U'Ad~~
询,接下来编写UserDAO的代码: $ 6Nm`[V
3. UserDAO 和 UserDAOImpl: hy3[MOD$G
java代码: /^P^K
lk1c2
$_@~t$
/*Created on 2005-7-15*/ Kg~<h B6
package com.adt.dao; !b7]n-1zs
E)09M%fe
import java.util.List; Y^2`)':
`0=0IPVd
import org.flyware.util.page.Page; p%]*I?
>O9j},X
import net.sf.hibernate.HibernateException; C!Y|k.`p
~ifq_Ag.
/** DSizr4R
* @author Joa \#m;L/D
*/ ^ Gq2"rDM
publicinterface UserDAO extends BaseDAO { 1AjsAi,7;2
w4:n(.;HK
publicList getUserByName(String name)throws 4)]g=-3
]BO{Q+?d2
HibernateException; G|4 vnIS
!jU<(eY
publicint getUserCount()throws HibernateException; 23_<u]V
dt',)i8D
publicList getUserByPage(Page page)throws H{\tQ->(2
2t<
dCw
HibernateException; "SNsOf
o~NeS|a
} MN$j{+ !Q
ga4 gH>4
l^uP?l"
mB"zyL-
l0U6eOx
java代码: _ZzN}!Mye
kZU8s'C
eG"iJ%I
/*Created on 2005-7-15*/ _-%ay
package com.adt.dao.impl; W ;P1T"*A
T9t9])
import java.util.List; HAf.LdnzS
Jtd@8fVi
import org.flyware.util.page.Page; Te[[xhTyw
[l-zU}u&v
import net.sf.hibernate.HibernateException; >u*woNw(XM
import net.sf.hibernate.Query; yx{Ac|<mR
JV36@DVQ
import com.adt.dao.UserDAO; \$?[>=<wB
Y@9L8XNP>
/** R>/M>*C
* @author Joa **_VNDK+
*/ c*RZbE9k
public class UserDAOImpl extends BaseDAOHibernateImpl #xW%RF
-fL|e/
implements UserDAO { iV'-j,-i
s.=)p"pTd
/* (non-Javadoc) z9w@-])
* @see com.adt.dao.UserDAO#getUserByName qE$.a[
.Z%7+[
(java.lang.String) kgr:85
*/ &0(2Z^Z>fw
publicList getUserByName(String name)throws h,FP,w;G
d2.n^Q"?3
HibernateException { _9!Ru!u~
String querySentence = "FROM user in class =!#DUfQf
JO :m:
M
com.adt.po.User WHERE user.name=:name"; mKe{y.
Query query = getSession().createQuery }^`{YD
JGj_{|=:
(querySentence); !PUhdW
query.setParameter("name", name); MYN1zYT6j
return query.list(); s3J T1TX
} $ZcmE<7k
KOi%zE%
/* (non-Javadoc) hp,T(D|
* @see com.adt.dao.UserDAO#getUserCount() X@~sIUXx9
*/ }ZVNDvGH
publicint getUserCount()throws HibernateException { Qbv)(&i#~
int count = 0; \R79^
String querySentence = "SELECT count(*) FROM )B}]0`z:P
`&pb`P<`
user in class com.adt.po.User"; Rx`0VQ
Query query = getSession().createQuery D"^ogY#LK
QRdb~f;<hj
(querySentence); +s[(CI.b
count = ((Integer)query.iterate().next t8?+yG;
K9w24Oka
()).intValue(); 3>L1}zyM]
return count; Ho\+xX
} lPFMNRt~8
TS
UN(_XGW
/* (non-Javadoc) A)`M*(~
* @see com.adt.dao.UserDAO#getUserByPage 8De
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TzK?bbgr!
(org.flyware.util.page.Page) NoKYHN^*w
*/ C{2UPG4 x
publicList getUserByPage(Page page)throws %+pXzw`B
!. 0W?6yo
HibernateException { ImF/RKI~ "
String querySentence = "FROM user in class ~)ByARao=
u"|.]r
com.adt.po.User"; Pv0+`>):
Query query = getSession().createQuery 7s.sbP~
\{UiGCK
(querySentence); ko,
u
query.setFirstResult(page.getBeginIndex()) /5=A#G
.setMaxResults(page.getEveryPage());
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return query.list(); Q7DkhKT
} Xt7uCs
eA+6-'qN
} tGf
5|>jz `
\}<nXn!
#v~5f;[AAs
Z>X-u eV
至此,一个完整的分页程序完成。前台的只需要调用 _Y~+ #Vc
SgY>$gP9S
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;XTP^W!6f
EL+}ab2S
的综合体,而传入的参数page对象则可以由前台传入,如果用 =XWi+')
bF}~9WEa
webwork,甚至可以直接在配置文件中指定。 2smLv1w@
xUeLX`73
下面给出一个webwork调用示例: \?GMtM,
java代码: M"V?fn'
'7E?|B0],
J@)6]d/,
/*Created on 2005-6-17*/ a"ht\v}1
package com.adt.action.user; dwmj*+
#nu?b?X'
import java.util.List; my*/MC^O
ikofJl]9
import org.apache.commons.logging.Log; g.,IQ4o
import org.apache.commons.logging.LogFactory; hx:x5L>
import org.flyware.util.page.Page; EmH2 Dbw
TYB^CVSZ
import com.adt.bo.Result; C$?dkmIt
import com.adt.service.UserService; 3|@Ske1%Y
import com.opensymphony.xwork.Action; >S!QvyM(V
hB|LW^@v
/** +='.uc_
* @author Joa ;zp0,[r
*/ Z,Q)\W<'-
publicclass ListUser implementsAction{ :.Np7[~{
N.3M~0M*
privatestaticfinal Log logger = LogFactory.getLog CRS/qso[Q'
oU{m\r
(ListUser.class); &%INfl>o7.
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private UserService userService; Y.=v!*p?}
#,$d!l @
private Page page; dx:],VB
0h$23.
privateList users; [['un\~r~
bl:.D~@
/* EAx@a%
* (non-Javadoc) 3;#v$F8R
* ?mrG^TV^+r
* @see com.opensymphony.xwork.Action#execute() }}K44<]u
*/ :3u>%
publicString execute()throwsException{ YB~}!F [(
Result result = userService.listUser(page); XG*Luc-v
page = result.getPage(); `2UzJ~
users = result.getContent(); lS9rgq<n
return SUCCESS; $I+QyKO9k
} YW0UIO
sy#CR4X
/** IU/dY`J1
* @return Returns the page. F}.<x5I-;h
*/ .J'}qkz~
public Page getPage(){ @)|62Dv /
return page; jj.i W@m
} ~[ isR|>
eDgRYa9\
/** 3<CCC+47
* @return Returns the users. MAQkk%6[g
*/ f9F@G&&Ugg
publicList getUsers(){ $9j\sZj&
return users; k*[["u^u]
} (n|PLi
VW$ Hzx_z
/** -]\UFR
* @param page 6ix8P;;}#
* The page to set. kW3V"twx
*/ .B+R+2uY3
publicvoid setPage(Page page){ n0:'h}^
this.page = page; D({%FQ"
} >A;Mf*E
nK)U.SZ
/** ~q5" '
* @param users |^[]Oy=
* The users to set. cLEBcTx
*/ 540-l Me
publicvoid setUsers(List users){ 9,sj,A1
this.users = users; ,|<2wn#q
} gu7mGHn-
{m.l{<H
/** z:{'IY
* @param userService 6-c3v
* The userService to set. I6,'o)l{_
*/ 0,1:l3iu1M
publicvoid setUserService(UserService userService){ /GD4GWv :
this.userService = userService; 0&mOu #l
} zxTcjC)y
} n,q+EZd
e
C?adCb
/7/d
u[P6
"l &=a1l
>RZ]t[)y
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, # -e
h,o/(GNnW
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 N}HQvlLkF9
?-1r$z
么只需要: A[`c2v-hF
java代码: ,K'>s<}
~w_4
nE
MB06=N
<?xml version="1.0"?> (99P9\[p
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork =
_X#JP79
l?2(c
1.0//EN" "http://www.opensymphony.com/xwork/xwork- (C>FM8$J
m7}PJ^*b
1.0.dtd"> 62GP1qH9
PLD6Ug
<xwork> bL
soKe
pESlBQ7{I
<package name="user" extends="webwork- &.J8O+
nm5zX,
interceptors"> _ZX"gHx
wTb7 xBI
<!-- The default interceptor stack name ^L#\z7
R1OC7q
--> A[)od
<default-interceptor-ref VtIPw&KHW
-;9pZ'r
name="myDefaultWebStack"/> Jf6uE?.
=.NZ{G
<action name="listUser" 9ZFvN*Zf'
3yg22y&l
class="com.adt.action.user.ListUser"> o (fZZ`6Y
<param B^g+_;
x}Qet4vV
name="page.everyPage">10</param> H^_]' ~.
<result F[m"eEX
JA0$Fz
name="success">/user/user_list.jsp</result> 0s )B~
</action> D>"U0*h
*AX)QKQ@
</package> pgT XyAP{
7
+A-S9P)
</xwork> \;AW/&Ea
@gzm4
BkfWZ O{7
8was/^9;
2B&Yw
SjgF&LD
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 8qwc]f$.w
k#"Pv"
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。 a,X=!oJ
h
$)thW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 cy)b/4h@
N!" ]e*q
Kp,}7%hDw!
mw}obblR
N,v4SIC@
我写的一个用于分页的类,用了泛型了,hoho
2{naSiaq
XvBEC_xWZ
java代码: }G
n2%
;:xOW$
il^SGH
package com.intokr.util; $s2Ty1
w`XwW#!}@$
import java.util.List; ,Ie~zZE&
wqDRFZ1*P
/** BcV;EEi
* 用于分页的类<br> !NuYx9L?L
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 4/D~H+k
* TnET1$@qr*
* @version 0.01 B.fLgQK0
* @author cheng lh`inAt)"
*/ 9R.IYnq
public class Paginator<E> { Zrfp4SlZZ
privateint count = 0; // 总记录数 ?QO)b9
privateint p = 1; // 页编号 #|^7{TN
privateint num = 20; // 每页的记录数 .K^'Q|?
privateList<E> results = null; // 结果 =DTn9}u
GEP YSp
/** )CS7>Vx
* 结果总数 Q6?+# }
*/ S8j;oJ2d
publicint getCount(){ 2^Gl;3
return count; M%4o0k]E,s
} nut;ohIh
@%J?[PG
publicvoid setCount(int count){ #FF5xe
this.count = count; l/OG79qq
} [ANit0-~
]OY6.m
/** jM
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* 本结果所在的页码,从1开始 j-$aa;
* sBp|Lo
* @return Returns the pageNo. `h5HA-ud
*/ Mr:*l`b_
publicint getP(){ 18w[T=7)
return p; 4,f[D9|:
} Q"8)'dL'
Sw#Ez-X
/** S|;a=K&hS
* if(p<=0) p=1 0<{/T*AU:
* {d(PH7R
* @param p 7=om /
*/ R#tz"T@
publicvoid setP(int p){ $Z10Zf=
if(p <= 0) 7|zt'.56[
p = 1; En6fmEn&;o
this.p = p; #f.@XIt'
} ni@D7:h
MS^,h>KI
/** w ;H
* 每页记录数量 : ` F>B
*/ CCq<y
publicint getNum(){ ~2@U85"o
return num; SfJ/(q
} UkNC|#l)
$$ _ uQf
/** e_]1e7t
* if(num<1) num=1 /G[y
24 Q
*/ Ms1\J2
publicvoid setNum(int num){ !::k\}DS
if(num < 1) z('93vsO
num = 1; 9][Mw[k>
this.num = num; uNXh"?
} AG}'
W
Z+t?ah00
/** N_pJE?
* 获得总页数 @{I55EQ]
*/ Cy6[p
publicint getPageNum(){ ::H jpM
return(count - 1) / num + 1; .e.vh:Sz
} jn}6yXB
" "a+Nc
/** ,eUMSg~P.7
* 获得本页的开始编号,为 (p-1)*num+1 ]v_xEH}T
*/ 73}k[e7e
publicint getStart(){ DA@
{ d-A
return(p - 1) * num + 1; _%zU^aE
} ,7%(Jj$
^
$Uewv
+
/** w4L\@y3
* @return Returns the results. Tg:NeAN7(
*/ )1x333.[c
publicList<E> getResults(){ H8\{GGg
return results; 3&' STPpW
} gX(QRQ
H50nR$$<*Y
public void setResults(List<E> results){ _4E+7+
this.results = results; N,[M8n,
}
vN4X%^:(
sL/Lw
WH
public String toString(){ aO<d`DTyJ
StringBuilder buff = new StringBuilder 7H>dv'
b/5~VY*T
(); :sA-$*&x
buff.append("{"); N@d4)
buff.append("count:").append(count); ` j Un
buff.append(",p:").append(p); _v$mGZpGY
buff.append(",nump:").append(num); T2(+HI2
buff.append(",results:").append I"
j7
uPo>?hpq+
(results); ,~4(td+R7
buff.append("}"); M]_vb,=1
return buff.toString(); "R30oA#m
} =G72`]#-
>=Rb:#UM
} s~63JDy"E
l{pF^?K
%vThbP#mR|