Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 F10TvJ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1!W'0LPM
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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 E RjMe'q4
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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!]Iqz"N
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分页支持类: Sf'uKSX1%
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java代码: *h
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package com.javaeye.common.util; PW+B&7{
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import java.util.List; >Xi/ p$$7u
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publicclass PaginationSupport { R!rj:f!>
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publicfinalstaticint PAGESIZE = 30; [Om,Q<
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privateint pageSize = PAGESIZE; @_0tq {
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privateList items; k
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privateint totalCount; vK`HgRQ(C
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privateint[] indexes = newint[0]; 5{#s<%b.
}9glr]=
privateint startIndex = 0; ([^#.x)hz
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public PaginationSupport(List items, int KuW>^mF(I
#c":y5:
totalCount){ @4MQ021(
setPageSize(PAGESIZE); |KVVPXtq%C
setTotalCount(totalCount); 3SI0etVr
setItems(items); Q*M(d\V s
setStartIndex(0); &n#yxv4
} oz]&=>$1I
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public PaginationSupport(List items, int 8vtembna4
:H&G}T(#
totalCount, int startIndex){ ^do6?e`?-
setPageSize(PAGESIZE); I>##iiKN
setTotalCount(totalCount); hgzNEx%^q
setItems(items); t\a|Gp W
setStartIndex(startIndex); fms(_Q:R?
} 0igB pHS
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public PaginationSupport(List items, int u~2]$ /U
||.Hv[
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totalCount, int pageSize, int startIndex){ .gzfaxi
setPageSize(pageSize); ^\kH^
setTotalCount(totalCount); 3Pgokj
setItems(items); ,,+4d :8$
setStartIndex(startIndex); (CgvI*O
} k#u)+e.'
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publicList getItems(){ nm& pn*1
return items; pPag@L
} yTh%[k
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publicvoid setItems(List items){ vC`SD]
this.items = items; }ijQ*ECdl
} `CC=?E
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publicint getPageSize(){ >iRkhA=Vg
return pageSize; .Od@i$E>&
} '\QJ{/JV
R[j'<gd.
publicvoid setPageSize(int pageSize){ I[A<e]uK
this.pageSize = pageSize; 9/8+R%
} a:P+HU:
@[FO;4w
publicint getTotalCount(){ s-6$C
return totalCount; :
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} Y, Lpv|
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publicvoid setTotalCount(int totalCount){ \|vo@E
if(totalCount > 0){ D|Tz{DRG
this.totalCount = totalCount; , MqoX-+
int count = totalCount / <bJ|WS|
@}^VA9ULK
pageSize; k{!9f=^
if(totalCount % pageSize > 0) a"}ndrc*
count++; pQZ`dS\
indexes = newint[count]; @(6P L^I
for(int i = 0; i < count; i++){ t0<RtIh9e
indexes = pageSize * P7X3>5<;q
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i; 'o=DGm2H
} 7<:o4\q?m
}else{ 0T@axQ[%
this.totalCount = 0; wk?i\vm
} Bvj
} n[;)(
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publicint[] getIndexes(){ VeEa17g&
return indexes; x*j
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} a$iDn_{
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publicvoid setIndexes(int[] indexes){ non5e)w3@
this.indexes = indexes; Z6So5r%wZ
} _iA oNT!
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publicint getStartIndex(){ wU/fGg*M2
return startIndex; wqjR-$c
} $PlMyLu7jc
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publicvoid setStartIndex(int startIndex){ S6JWsi4C:,
if(totalCount <= 0) 4"nYxL"<4
this.startIndex = 0; ',D%,N}J
elseif(startIndex >= totalCount) 0<<ATw$aQ
this.startIndex = indexes RP 6<#tq,
c[3x>f0
[indexes.length - 1]; $E8}||d
elseif(startIndex < 0) Htln <N
this.startIndex = 0; 6E9/z
else{ ZE~zs~z|
this.startIndex = indexes MX.?tN#F|H
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[startIndex / pageSize]; ^Xu4N"@
} ou<,c?nNM
} Ndgx@LTQQ
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publicint getNextIndex(){ TY'61xWi
int nextIndex = getStartIndex() + "^a"`?J
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pageSize;
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if(nextIndex >= totalCount) 9cU9'r# h
return getStartIndex(); J_-fs#[x
else {IaDZ/XS6
return nextIndex; bovAFdHW
} Id>4fF:o
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publicint getPreviousIndex(){ zNdkwj p+
int previousIndex = getStartIndex() - 4v3gpLH
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pageSize; gq/Za/!6
if(previousIndex < 0) 1?1Bz?EKF*
return0; 0\X<vrW
else -B&(&R
return previousIndex; %Ta"H3ZW
} ~(kqq#=s
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} w^$C\bCbh
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抽象业务类 TjYHoL5
java代码: 2A[hMbL
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/** kLZVTVSJt
* Created on 2005-7-12 6=;(~k&x9:
*/ EwA*
package com.javaeye.common.business; %Uz\P|6PO
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import java.io.Serializable; 'wG1un;t
import java.util.List; 'xGhMgR;
/UK]lP^w]!
import org.hibernate.Criteria; =\5WYC
import org.hibernate.HibernateException; )H{1Xjh-
import org.hibernate.Session; Y%;X7VxU*
import org.hibernate.criterion.DetachedCriteria; :TG;W,`.V
import org.hibernate.criterion.Projections; s(3HZ>qx;
import 10*Tk 8
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org.springframework.orm.hibernate3.HibernateCallback; }9fch9>Zr
import ,}gJY^X+
$["HC-n?.k
org.springframework.orm.hibernate3.support.HibernateDaoS 1p$(\
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upport; n9}BT^4 v
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import com.javaeye.common.util.PaginationSupport; R^o535pozc
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public abstract class AbstractManager extends BOw[*hM
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HibernateDaoSupport { ~1wt=Ln>
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privateboolean cacheQueries = false; fI<LxU_n:
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privateString queryCacheRegion; EOXkMr
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publicvoid setCacheQueries(boolean {/,(F^T>2
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cacheQueries){ ?%hd3zc+f
this.cacheQueries = cacheQueries; ~rdS#f&R2
} N'WTIM3W
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publicvoid setQueryCacheRegion(String f^B8!EY#:
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queryCacheRegion){ -6kX?sNl)X
this.queryCacheRegion = t,|Apl]
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queryCacheRegion; ?j.a>{
} I!*P' {lh
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publicvoid save(finalObject entity){ GEc-<`-
getHibernateTemplate().save(entity); /g{*px|
} QjY}$
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publicvoid persist(finalObject entity){ IeYNTk&<
getHibernateTemplate().save(entity); C`i#7zsH
} h@$SJe(hl
M> WWP3
publicvoid update(finalObject entity){ P ljPhAce
getHibernateTemplate().update(entity); pJ/]\>#5
} qP#LJPaS
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publicvoid delete(finalObject entity){ yO)xN=o^\
getHibernateTemplate().delete(entity); auK9wQ%\
} { im?tZ,
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publicObject load(finalClass entity, p]RQ-0
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finalSerializable id){ (yP1}?
return getHibernateTemplate().load #wIWh^^ Zy
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(entity, id); IN bV6jZL
} md+pS"8o;
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publicObject get(finalClass entity, +=E\sEe
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finalSerializable id){ Y
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return getHibernateTemplate().get 62R";# K
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(entity, id); N E9,kWI
} ny13+Q`^
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publicList findAll(finalClass entity){ ~#)hqU'
return getHibernateTemplate().find("from CHKhJ v3+4
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" + entity.getName()); VNWB$mM.2
} B=d<L^
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publicList findByNamedQuery(finalString {OPEW`F
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namedQuery){ %RV81H9B
return getHibernateTemplate % vUU
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().findByNamedQuery(namedQuery); h-ii-c?R@0
} J;_4
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publicList findByNamedQuery(finalString query, vGv<WEE
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finalObject parameter){ LMoZI0)x
return getHibernateTemplate F@Sk=l(
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().findByNamedQuery(query, parameter); 9k;,WU(K<
} sn:VM HrOT
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publicList findByNamedQuery(finalString query, 7/~=[#]*
|-V:#1wR.]
finalObject[] parameters){ 5oG~ Fc
return getHibernateTemplate Kc\8GkdB
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().findByNamedQuery(query, parameters); Cik1~5iF
} (/I6Wa
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publicList find(finalString query){ f9K7^qwkiz
return getHibernateTemplate().find E\/[hT
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(query); vgy.fP"@
} O;RBK&P
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publicList find(finalString query, finalObject ,1~zYL?
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parameter){ X?t;uZI^
return getHibernateTemplate().find /HRKw
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(query, parameter); 60%nQhb
} Q8`V0E\~
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public PaginationSupport findPageByCriteria 2p, U ^h
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(final DetachedCriteria detachedCriteria){ 4o}{3! m
return findPageByCriteria 9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &fB=&jc*j
} 3;L$&X2
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public PaginationSupport findPageByCriteria BO*)cLQ
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(final DetachedCriteria detachedCriteria, finalint V$hL\`e
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startIndex){ jz"
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return findPageByCriteria ({rcH.:
@H`jDaB9
(detachedCriteria, PaginationSupport.PAGESIZE, %"r9;^bj&<
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startIndex); L~PiDQr?r
} YT8q0BR]
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public PaginationSupport findPageByCriteria 5!A:xV]6]
w` +,
(final DetachedCriteria detachedCriteria, finalint H4`>B>\
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pageSize, >/\TG8t,f
finalint startIndex){ @}6<,;|DQ
return(PaginationSupport) <J%Z?3@T
cz IEkm
getHibernateTemplate().execute(new HibernateCallback(){ qZ!kVrmg&
publicObject doInHibernate (.=Y_g.
L@O>;zp;
(Session session)throws HibernateException { TXM/+sd
Criteria criteria = \h'7[vkr
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detachedCriteria.getExecutableCriteria(session); AQ$)JPs
int totalCount = T+T)~!{%
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((Integer) criteria.setProjection(Projections.rowCount mRAt5a#is
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()).uniqueResult()).intValue(); {wM<i
criteria.setProjection {f/]K GGk
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(null); e+!xy&u@u
List items = (L4llZ;q
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criteria.setFirstResult(startIndex).setMaxResults c[2ikI,n[
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(pageSize).list(); k(Xs&f
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PaginationSupport ps = K?,?.!ev
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new PaginationSupport(items, totalCount, pageSize, FWeUZI+
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startIndex); <LH6my
return ps; i?d545. u
} #QsJr_=
}, true); [L-wAk:Fb
} W2-l_{
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public List findAllByCriteria(final ncadVheKt
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DetachedCriteria detachedCriteria){ VTR4uT-
return(List) getHibernateTemplate A-B>VX
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().execute(new HibernateCallback(){ tkm@&e=e%
publicObject doInHibernate ?99r>01>
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(Session session)throws HibernateException { v B~VJKD
Criteria criteria = 13 L&f\b
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detachedCriteria.getExecutableCriteria(session); \kV|S=~@
return criteria.list(); ]O:u9If
} C8v
}, true); wvisu\V
} O0r vr$.
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public int getCountByCriteria(final fup?Mg-
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DetachedCriteria detachedCriteria){ V%;dTCq
Integer count = (Integer) P//nYPyzg
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getHibernateTemplate().execute(new HibernateCallback(){ yz,_\{}
publicObject doInHibernate pk'd&.
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(Session session)throws HibernateException { Y5ei:r|^
Criteria criteria = R-W.$-rF
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detachedCriteria.getExecutableCriteria(session); ~x4]p|)</
return @\gE{;a8
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criteria.setProjection(Projections.rowCount E0HE@pqr
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()).uniqueResult(); U7/
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} 0H%zkJ>Q
}, true); =Gj~:|;$
return count.intValue(); #D(=[F
} {C?$osrr
} N`,,sw
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用户在web层构造查询条件detachedCriteria,和可选的 |'o<w
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}9B},
startIndex,调用业务bean的相应findByCriteria方法,返回一个 >40B
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PaginationSupport的实例ps。 #Id.MLHxA_
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ps.getItems()得到已分页好的结果集 'e6W$?z
ps.getIndexes()得到分页索引的数组 2|k*rv}l
ps.getTotalCount()得到总结果数 B0c} 5V
ps.getStartIndex()当前分页索引 9X&Xs/B
ps.getNextIndex()下一页索引 ;WIL?[;w
ps.getPreviousIndex()上一页索引 }@'xEx
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 PF .sM(
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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 rL URP2~
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一下代码重构了。 0:G@a&Lr
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我把原本我的做法也提供出来供大家讨论吧: tYfhKJzGC
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首先,为了实现分页查询,我封装了一个Page类: -b@E@uAX/
java代码: +Z XGT
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/*Created on 2005-4-14*/ 8O{]ML
package org.flyware.util.page; M
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/** kt1f2cj
* @author Joa 0jv9N6IM
* V`69%35*@
*/ ]_BG"IR!..
publicclass Page {
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/** imply if the page has previous page */ hl~(&D1^
privateboolean hasPrePage; M
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/** imply if the page has next page */ 3:Co K#
privateboolean hasNextPage; ](_(1
v,>F0ofJ
/** the number of every page */ %o4d43uZ
privateint everyPage; s*k"-5
@YwaOc_%
/** the total page number */ SATZ!
privateint totalPage; V2/+SvB2
ciC4V^f
/** the number of current page */ d+T]EpQJ*
privateint currentPage; {OAy@6
+
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/** the begin index of the records by the current \((>i7C
1Y9Ye?~jd
query */ r.ajw&J2
privateint beginIndex; ?7&VT1
!y] Y'j
F$ h/k^
/** The default constructor */ 1}jE?{V*
public Page(){ W|e>
^ym{DSx
} Qg!*=<b
L#Y;a
5b
/** construct the page by everyPage {SJ7Yfs
* @param everyPage BkfBFUDQ
* */
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public Page(int everyPage){ )S;ps
this.everyPage = everyPage; dCTpO
} *Mc\7D
M3 u8NRd5|
/** The whole constructor */ ooSd6;'
public Page(boolean hasPrePage, boolean hasNextPage, 55b |zf
%ko 8P
iXRt9)MT{
int everyPage, int totalPage, ie5ijkxZ(
int currentPage, int beginIndex){ DG?\6Zh
this.hasPrePage = hasPrePage; )du{ZWr
this.hasNextPage = hasNextPage; qL.Y_,[[
this.everyPage = everyPage; ]#.&f]6l
this.totalPage = totalPage; !
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this.currentPage = currentPage; y03a\K5[KQ
this.beginIndex = beginIndex; ;_5
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} .G~5F- 8'
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/** 7=A9E]:
* @return RsfTUb)<
* Returns the beginIndex. \Pmk`^T
*/ >%dAqYi $
publicint getBeginIndex(){ RpP[ymMZJ
return beginIndex; M~F2cXW
} vXQmEIm
R6mJFE*6T9
/** , %O3^7i
* @param beginIndex 72vGfT2HtZ
* The beginIndex to set. Ytwv=;h-
*/ q.[[c
publicvoid setBeginIndex(int beginIndex){ .OS?^\
this.beginIndex = beginIndex; c.A/{a
} C,vc
aC?
@SG"t,5s
/** Nw&}qSN
* @return |Umfq:W`y_
* Returns the currentPage. Ny7=-]N4{"
*/ i=H>D
publicint getCurrentPage(){ Mv`L F
return currentPage; R&_\&:4f
} *Q120R
7"NJraQ6
/** fA0=Y,pzv
* @param currentPage xYVjUb(,X
* The currentPage to set. 7+hF;
*/ IBNQmVRrI
publicvoid setCurrentPage(int currentPage){ seU^IC<
this.currentPage = currentPage; n9fA!Wic
} gIM'bA<~
9`n)"r
/** f3>6:(
* @return [67E5rk-
* Returns the everyPage. -hFyqIJW
*/ 1
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publicint getEveryPage(){ ^zPEAXm
return everyPage; bd
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} B"Kce"!
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/** `CEj 4
* @param everyPage [gns8F#H\
* The everyPage to set. OC>_=i$'
*/ #!u51P1
publicvoid setEveryPage(int everyPage){ xm,`4WdG
this.everyPage = everyPage; u}LX,B-n(
} sqpOS!]
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/** i|]Va44
* @return hn\Q6f+
* Returns the hasNextPage. [aM'
*/ .i&ZT}v3
publicboolean getHasNextPage(){ }wOpPN[4
return hasNextPage; fxoi<!|iGY
} }B9~X
1.95 ^8
/** waWKpk1Wo
* @param hasNextPage ,WB_C\.#XN
* The hasNextPage to set. "`i:)E t
*/ H1%[\X?=
publicvoid setHasNextPage(boolean hasNextPage){ u|OzW}xb7j
this.hasNextPage = hasNextPage; ^L-w(r62<
} ^2C /!Y<
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/** 4]aiT8))
* @return pba8=Z
* Returns the hasPrePage. h#m:Y~GoF
*/ pgd8`$(Q
publicboolean getHasPrePage(){ <{cNgKd9
return hasPrePage; (e8G
(
} wLOQhviI^-
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/** 46K&$6eN
* @param hasPrePage QOV}5 0
* The hasPrePage to set. 45+%K@@x
*/ hH1lgc
publicvoid setHasPrePage(boolean hasPrePage){ 4g7ja
this.hasPrePage = hasPrePage; sCF40AoY&
} @1qdd~B}
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/** ',JrY)
* @return Returns the totalPage. jWXR__>.
* { eEC:[
*/ I%9bPQ
publicint getTotalPage(){ kYxl1nv
return totalPage; @q&|MMLt
} y7JZKtsFA
4O`6h)!NQ
/** ok `]:gf
* @param totalPage MCk^Tp!
* The totalPage to set. zb5N,!%r
*/ ,M)k7t:
publicvoid setTotalPage(int totalPage){ b4Cfd?'
this.totalPage = totalPage; L6:W'u^
} q]6_rY.
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} s) Cpi
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 xfq]9<
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个PageUtil,负责对Page对象进行构造: JbE?a[Eg?
java代码: Ag0]U
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/*Created on 2005-4-14*/ oQJtUP%
package org.flyware.util.page; x]j W<A
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import org.apache.commons.logging.Log; I7]8Y=xf
import org.apache.commons.logging.LogFactory; #GFr`o0$^
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/** CWKm(@"5
* @author Joa gjlx~.0d
* apn*,7ps65
*/ 7zj{wp!
publicclass PageUtil { |DwZ{(R"W
r.U`Kh]K
privatestaticfinal Log logger = LogFactory.getLog ?e?!3Bx;EM
kq-) ^,{y
(PageUtil.class); "<gOzXpa
* v#o
/** @2#lI
* Use the origin page to create a new page @ Nm@]q
* @param page F"mmLao
* @param totalRecords vP,n(reM
* @return !VzC&>'v^9
*/ J .<F"r>
publicstatic Page createPage(Page page, int fV~[;e;U.
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totalRecords){ 0*v2y*2V
return createPage(page.getEveryPage(), 2~2 O V
q.}CU.dp
page.getCurrentPage(), totalRecords); 19] E 5'AI
} (;,sc$H]
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/** }QmqoCAE~m
* the basic page utils not including exception Pzem{y7Ir
u1.BN>G
handler 1.>m@Slr>
* @param everyPage t#yuOUg
* @param currentPage A=>u
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* @param totalRecords "Y.y:Vv;
* @return page 2A!FDr~cdT
*/ phz&zlD
publicstatic Page createPage(int everyPage, int #LNED)Vg
d d;T-wa}
currentPage, int totalRecords){ TsZ@
everyPage = getEveryPage(everyPage); Q59W#e)
currentPage = getCurrentPage(currentPage); !_(Tqyg&
int beginIndex = getBeginIndex(everyPage, :gC#hmm^
`y0FY&y=
currentPage); FgO)DQm
int totalPage = getTotalPage(everyPage, M^I(OuRMeI
aQ~s`^D
totalRecords); %XTI-B/K
boolean hasNextPage = hasNextPage(currentPage, XfmwVjy
dqAw5[qMJ
totalPage); ']oQ]Yx0
boolean hasPrePage = hasPrePage(currentPage); S
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returnnew Page(hasPrePage, hasNextPage, <-0]i_4sK
everyPage, totalPage, mA} "a<0
currentPage, O
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ctV,Q3'Z
beginIndex); I2DpRMy
} B1Oq!k
=Runf
+}
privatestaticint getEveryPage(int everyPage){ z$Qbj
return everyPage == 0 ? 10 : everyPage; C.QO#b
} 8EEuv-aeo
Er[A X.3
privatestaticint getCurrentPage(int currentPage){ b>$S<td
return currentPage == 0 ? 1 : currentPage; 3mni>*q7d
} |Ds=)S"
K
,2)6s\]/b
privatestaticint getBeginIndex(int everyPage, int RGX=)
DeYV$W
B
currentPage){ P
}uOJVQ_
return(currentPage - 1) * everyPage; Cls%M5MH
} s<o7!!c
4`R(?
privatestaticint getTotalPage(int everyPage, int vcd\GN*4f
wdZ/Xp9]
totalRecords){ ]:\dPw`A
int totalPage = 0; 9k=3u;$v
3k?X-|O8AZ
if(totalRecords % everyPage == 0) Q5_o/wk
totalPage = totalRecords / everyPage; [trwBZ^D~
else K4);HJ|=
totalPage = totalRecords / everyPage + 1 ; snikn&
'P}0FktP`
return totalPage; ,v&(Y Od
} qjc4.,/
O| hpXkV
privatestaticboolean hasPrePage(int currentPage){ 4H<lm*!^
return currentPage == 1 ? false : true; OUXR
} 188*XCtjQ9
j8`BdKg
privatestaticboolean hasNextPage(int currentPage, ~3 bPIg7D
;({W#Wa
int totalPage){ 4a]P7fx-
return currentPage == totalPage || totalPage == b%5f&N
tnG# IU
*
0 ? false : true; yvYad
} O0y_Lm\
O8.5}>gDn.
,4oo=&
} ?K\axf>F
_ORvo{[:
VM,]X.
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}AH]
th
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。 1y4
Ez=Olbk
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 %|i`kYsy
:Zz
'1C
做法如下: zI<<Q2
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \;"=QmRD%:
iW /}#
的信息,和一个结果集List: }!C)}.L<
java代码: {,~3.5u
q%?in+l
FG*r'tC~r
/*Created on 2005-6-13*/ .h4 \Y A
package com.adt.bo; J
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NPe%F+X
import java.util.List; \)?HJ
fsWTF<Y
import org.flyware.util.page.Page; p"ZG%Ow5Q]
Fun^B;GA:
/** ';=O 0)u
* @author Joa %Q dn
*/ Ak"m 85B
publicclass Result { ;x@~A^<el
[ ~&/s:Vvo
private Page page; exUu7&*:
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private List content; b?QoS|<e?
d,n 'n
/** ]F'e
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* The default constructor FE|JHh$
*/ P! #[mio
public Result(){ OA"q[s
super(); &AbNWtCV+G
} W+ko q*P
J,y[[CdH`
/** l#Y,R 0
* The constructor using fields S2VA{9:m
* FSW_<%
* @param page Ks`J([(W&
* @param content {:$>t~=D
*/ 9H`XeQ.
public Result(Page page, List content){ R3&Iu=g
this.page = page; %.-4!vj
this.content = content; 65$+{s
} 4-H+vNG{%
JNXq.;:`Q
/** A1>OY^p3%
* @return Returns the content.
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*/ N.{H,oO `
publicList getContent(){ JL}_72gs
return content; c>:wd@w
} Mc_YPR:C
EGU
0)<
/** =BAW[%1b
* @return Returns the page. ex (.=X 1
*/ EF}\brD1
public Page getPage(){ [H^z-6x:0
return page; iYm-tsER;
} >T3-
3z9d!I^>k
/** ]e>w}L(gV
* @param content }1i`6`y1
* The content to set. ^{;oM^Q'
*/ O6a<`]F
public void setContent(List content){ < ?}-$
this.content = content; })8N5C+KU
} as4;:
zFws:_ i
/** cyv`B3}
* @param page {19PL8B~}
* The page to set. ju8q?Nyhs
*/ ujq=F
publicvoid setPage(Page page){ BBRR)
this.page = page; )E@.!Ut4o
} uHvp;]/0\
} A) %/[GD2
BsqP?/
#crQ1p) \
D] jzAx
FR4QUk
2. 编写业务逻辑接口,并实现它(UserManager, #TX/aKr:
tip+q d
UserManagerImpl) i6tf2oqO7
java代码: w/S%YW3*
kmsb hYM)
i,E{f
/*Created on 2005-7-15*/ O-~7b(Z
package com.adt.service; [.'|_l
QP^Cx=
import net.sf.hibernate.HibernateException;
bv9i*]
otl0JHt*+
import org.flyware.util.page.Page; LX7FaW
|\<`Ib4j
import com.adt.bo.Result; eJVjuG
}=UHbU.n~!
/** V>)OpvoT#
* @author Joa $@Rxrx_@M
*/ ^aMg/.j
publicinterface UserManager { djQH1^(IU
S)k*?dQ##R
public Result listUser(Page page)throws ?'#`
nx(!
oMD>Ywc-
HibernateException; nntuLuW
|`Ntv}
} Z!#!Gu*V
,p@y]
cr
ICoHI
k\YG^I
5C*Pd
Wpl
java代码: /k6MzFoid
P[#e/qnXu|
P*Uwg&Qz)
/*Created on 2005-7-15*/ Ic:(Gi- %
package com.adt.service.impl; Un(aW=PQ0
Eh;'S"{/?j
import java.util.List; Gg3,:A_ w
0r] t `{H
import net.sf.hibernate.HibernateException; <#y[gTJ<'>
'&R2 U_
import org.flyware.util.page.Page; [0[i5'K:
import org.flyware.util.page.PageUtil; A*R^n}sh
VimE@ Hz
import com.adt.bo.Result; 5 +YH.4R
import com.adt.dao.UserDAO; x{8xW0
import com.adt.exception.ObjectNotFoundException; Nw/ ku
import com.adt.service.UserManager; E`0?
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/** S6M}WR^,
* @author Joa #7$
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*/ A5RN5`}
publicclass UserManagerImpl implements UserManager { k&q;JyUi
ufZDF=$7
private UserDAO userDAO; 6NuD4Ga
D~fl JR
/** f:,DWw`B
* @param userDAO The userDAO to set. 8f4b&ah
*/ L>NL:68yN
publicvoid setUserDAO(UserDAO userDAO){ YnS#H"
this.userDAO = userDAO; Y%aCMP9j~9
} @|m/djN5x
FP`b>E qOH
/* (non-Javadoc) !bx;Ta.
* @see com.adt.service.UserManager#listUser kGS;sB
&|ex`nwc0
(org.flyware.util.page.Page) vY}g<*
*/ (k)v!O-
public Result listUser(Page page)throws a=1@*ID
*3FKt&v 0
HibernateException, ObjectNotFoundException { t%FwXaO#
int totalRecords = userDAO.getUserCount(); ^4hO
if(totalRecords == 0) beGa#JH,
throw new ObjectNotFoundException uc\Kg1{
P{jbl!UD7
("userNotExist"); [`[|l
page = PageUtil.createPage(page, totalRecords); v`x.)S1
List users = userDAO.getUserByPage(page); 1Z2HUzqh.
returnnew Result(page, users); RFc v^Xf
} 4Uo&d#o)C-
)
7@ `ut
} rJTa
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aCj&O:]=
vF+7V*<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 k FD;i
q`a'gJx#y
询,接下来编写UserDAO的代码: ]
vsz,
0
3. UserDAO 和 UserDAOImpl: @ioJ]$o7
java代码: MK~ 8}x 2K
j0aXyLNX
wo/\]5
/*Created on 2005-7-15*/ h"Q8b}$^)
package com.adt.dao; `25yE/
q!7ANib6O
import java.util.List; }C?'BRX
i)#dWFDTv
import org.flyware.util.page.Page; 2- h{N
#A/
import net.sf.hibernate.HibernateException; ((;!<5-`s
HM1Fz\Sf
/** j2[+ztG
* @author Joa LA5(sp@O
*/ &h)yro
publicinterface UserDAO extends BaseDAO { hWLA<wdb
f~R(D0@
publicList getUserByName(String name)throws _ <V)-Y
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3L'
HibernateException; |aS.a&vwR
B dfwa
publicint getUserCount()throws HibernateException; -@2iaQ(5a2
-d/
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publicList getUserByPage(Page page)throws : *#- %0
7xlkZF
HibernateException; L`TLgH&?R
)dw'BNz5hT
} )2o?#8J
4F:\-O
{}n^cq
Dml;#'IF3
^z*t%<@[Q
java代码: VCkq"f7cw
Bkc4TO
=y*IfG9b
/*Created on 2005-7-15*/ &r/Mi%
package com.adt.dao.impl; g:@#@1rB6
|wMN}bq|T
import java.util.List; F/{!tx
?l{nk5,?-Y
import org.flyware.util.page.Page; 2]*OQb#O6e
zC!t;*8a
import net.sf.hibernate.HibernateException; TIDO@NwF
import net.sf.hibernate.Query; ]%H`_8<gc
>+1duAC
import com.adt.dao.UserDAO; uGG t\.$]s
/,yd+wcW#
/** S%>]q
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* @author Joa bAqA1y3=
*/ j,eo2HaL
public class UserDAOImpl extends BaseDAOHibernateImpl 2/^3WY1U
b8UO,fY q
implements UserDAO { *i%d,w0+
C&%_a~
/* (non-Javadoc) tyFzSrfc
* @see com.adt.dao.UserDAO#getUserByName :5<UkN)R(
Bwxd&;E
(java.lang.String) vk^xT
*/ r,p%U!S<hV
publicList getUserByName(String name)throws lL3U8}vn
24eLB?H
HibernateException { Q197mN+0
String querySentence = "FROM user in class g) jYFfGfH
8lrpve
com.adt.po.User WHERE user.name=:name"; W|mo5qrLS2
Query query = getSession().createQuery 0GeTSFj
#\m<Sz5Gp#
(querySentence); f]CXu3w(J
query.setParameter("name", name); qX{+oy5
return query.list(); Dp9+HA9t
} 4tBYR9|
NBGH_6DROw
/* (non-Javadoc) ~9@UjQ^)F
* @see com.adt.dao.UserDAO#getUserCount() S,he6zS
*/ rx|pOz,:
publicint getUserCount()throws HibernateException { XSLFPTDEc
int count = 0; j\M?~=*w
String querySentence = "SELECT count(*) FROM ^1];S^nD
1yhDrpm
user in class com.adt.po.User"; s$j,9uRr
Query query = getSession().createQuery
&6VnySE?
K$=zi}J W
(querySentence); 8":Q)9;%
count = ((Integer)query.iterate().next FYQS)s
`ERz\`d~Y;
()).intValue(); S
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return count; @r1_U,0e
} kAUymds;O
BI@[\aRLQ
/* (non-Javadoc) ox.F%)eQ
* @see com.adt.dao.UserDAO#getUserByPage pQB."[n
Q~9^{sHZjP
(org.flyware.util.page.Page) Ny/MJ#Lq
*/ VIf.q)_k
publicList getUserByPage(Page page)throws t]G:L}AOl
JBZ@'8eqi]
HibernateException { I&5!=kR
String querySentence = "FROM user in class
]ZS
OM\}
8&dF
com.adt.po.User"; HGg@ _9tW
Query query = getSession().createQuery w0unS`\4
jebx40TA3
(querySentence); dPRra{
query.setFirstResult(page.getBeginIndex()) Vxt+]5X
.setMaxResults(page.getEveryPage()); Xch~
1K
return query.list(); )+Pus~w
} lp8v0e4
$ ocdI5
} GC'O[q+
qqU 64E
FpU>^'2]
dAj$1Ke
_o~nr]zx
至此,一个完整的分页程序完成。前台的只需要调用 gBD]}vo-
<OPArht
userManager.listUser(page)即可得到一个Page对象和结果集对象 Cgc\
ah
/qw.p#
的综合体,而传入的参数page对象则可以由前台传入,如果用 RD&PDXT4
=Fl^`*n
webwork,甚至可以直接在配置文件中指定。 u]@['7
5@W j>:w
下面给出一个webwork调用示例: }ad|g6i`
java代码: (7*}-Uy[C
v &+R^iLE
@KAI4LP
/*Created on 2005-6-17*/ 1BEHw?dLU
package com.adt.action.user; ~Cjn7
{(}By/_
import java.util.List; u#SWj,X
ehY5!D1Q
import org.apache.commons.logging.Log; t#"Grk8Mz&
import org.apache.commons.logging.LogFactory; ct}9i"H#1
import org.flyware.util.page.Page; E4xa[iZ
p()xz
import com.adt.bo.Result; Y
nZiTe@
import com.adt.service.UserService; `9.r`&T6K
import com.opensymphony.xwork.Action; PFK
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/** xkR0
* @author Joa v*yuE5{
*/ 8dyg1F
publicclass ListUser implementsAction{ S21,VpW\
f y8Uk;
privatestaticfinal Log logger = LogFactory.getLog */DO ex"y
#R
RRu2
(ListUser.class); 7t_^8I%[
Z EO WO
private UserService userService; 2GStN74X r
4xJQ!>6
private Page page; =mmWl9'mJ
\D&KC,i5f
privateList users; xn|(9#1o
BFW&2
/* t&Og $@
* (non-Javadoc) jlg(drTo
* 2dgd~
* @see com.opensymphony.xwork.Action#execute() D|#E9OQzs
*/ YT8F#t8
publicString execute()throwsException{ Pr,q*_Yy
Result result = userService.listUser(page); W+1^4::+
page = result.getPage(); R_xRp&5
users = result.getContent(); XBw)H
return SUCCESS; Vs{|xG7WD
} gKCX|cULY
Oz#{S:24M+
/** o,3a4nH;
* @return Returns the page. <_KIK
*/ {cw /!B
public Page getPage(){ $,fX:x
return page; eQvg7aO;
} ?@
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xA[mm
/** $]2vvr
* @return Returns the users. LB?u8>a' I
*/ , SnSW-P
publicList getUsers(){ *siFj
CN<
return users; u,Kly<0j
} Ok\7y-w^
>~+ELVB&
/** 0Z]!/AsC
* @param page TrR8?-
* The page to set. n>U5R_T
*/ z,%$+)K
publicvoid setPage(Page page){ yyy|Pw4:Z
this.page = page; )TM4R)r%)9
} .Rf_Cl
Tc3yS(aq
/** ;@E$}*3[>V
* @param users {3vNPQJ
* The users to set. 4#hSJ(~7S
*/ ?=fyc1
publicvoid setUsers(List users){ ! #2{hQRu
this.users = users; K8Y=S12Ti
} jsi!fx2Rm
,L'zRyP
/** vd4ytC
* @param userService ijx0gh`~
* The userService to set. Q6I:"2u1
*/ i&GH/y
publicvoid setUserService(UserService userService){ \v)+.m?n
this.userService = userService; A1zjPG&]
} G+\GaY[
} I`4*+a'q&
-_eLf#3
TT3|/zwn
SS.dY""89
hTi$.y!k
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, EG |A_m85
I"7u2"@-8j
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 l"]}Ts#
`$aZ0+
么只需要: V[vl!XM
java代码: 8StgsM
S\!ana])
-Wi` G
<?xml version="1.0"?> _[ZO p ~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _MX>#!l
j^rIH#V
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )
M BQuiL
l$bu%SZ
1.0.dtd"> >]5P
3\AQV
6MdiY1Lr!K
<xwork> _X"N1,0
?zHPJLv|Y
<package name="user" extends="webwork- :@A9](gI
@A^;jk
interceptors"> H-f X(9
m#Z#
.j_2
<!-- The default interceptor stack name !9P';p}2
ly3\e_z:G
--> PQ$%H>{
<default-interceptor-ref SPmq4
{
W{]L:
name="myDefaultWebStack"/> )*x6 FfTUd
*U=s\
<action name="listUser" k4y'b
q 2:6QM&
class="com.adt.action.user.ListUser"> &t:Gx<]
<param xw2[d+mB
+@k+2?]
FO
name="page.everyPage">10</param> ~d*(=G
<result +8Ymw:D7a
p\aaJ
name="success">/user/user_list.jsp</result> 6 EC*
</action> DG ;_Vg
oij}'|/Jc
</package> } .y
1;.
c?&X?<
</xwork> e 5*hE
b:]V`uF?
fbKkq.w
?8Z0Gqt74
NDlF0f
"PTZ%7YH}
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 X1-'COQS%&
kN4{13Qs*
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 v~V!ayn)wQ
``\i58K{e
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 v)t:|Q{I
<;m<8RjX
MWpQ^dL_
fc-iAj
KZ
;k)O.Ov
我写的一个用于分页的类,用了泛型了,hoho "h a L
6GSI"M6s
java代码: %9N7Ln|%
^N;.cY
<vh/4
package com.intokr.util; '~[d=fwH
QaS7z#/?.
import java.util.List; 2ZMb<b4H
6dN7_v)
/** ^O<&f D
* 用于分页的类<br> J^}V|#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !K}~/9Z=m
* `W:%mJd9
* @version 0.01 f'-i o<.
* @author cheng SmdjyK1~8
*/ 1V4s<m>#
public class Paginator<E> { &U
raUl
privateint count = 0; // 总记录数 =2zJ3&9
privateint p = 1; // 页编号 E.ly#2?
privateint num = 20; // 每页的记录数 ;":zkb{
privateList<E> results = null; // 结果 G!W[8UG
5eoska#y
/** gp^5#
* 结果总数 ];a=Pn-:}G
*/ ;WM"cJo9
publicint getCount(){ cc&axc7I
return count; v'qG26
} UXugRk%d
(m.ob+D
publicvoid setCount(int count){ *-q"3D`
this.count = count; >.'*)@vQi
} |e?64%l5P
g[Ib,la_a
/** s3O} 6
* 本结果所在的页码,从1开始 Q,AM<\S
* Bkq3-rX\
* @return Returns the pageNo. _7k6hVQ
*/ 8Ev,9
publicint getP(){ z}gfH|
return p; r/ G6O
} u` j9m@`
<*4'H
/** "c'K8,+?
* if(p<=0) p=1 uyfH;9L5$
* ophQdJM
* @param p v})-:
*/ 83|7#L
publicvoid setP(int p){ CSBk
if(p <= 0) doj$chy
p = 1; .&Q'aOg
this.p = p; kZfUwF:yN
} ?)2&LVrf
0>aAI3E
/** z4UJo!{S
* 每页记录数量 MU-T>S4
*/
=Eimbk
publicint getNum(){ <O]TM-h
return num; a-9Y U
} 4?vTuZ/
M
^Hplrwj}
/** g6wL\g{29
* if(num<1) num=1 {dk%j~w8
*/ BPH-g\q
publicvoid setNum(int num){ ZB|y
if(num < 1) "j<l=l!
num = 1; ~|>q)4is6a
this.num = num; MD62ObK!
} /3>5ex>PN
42If/N?
/** FkS$x'~2$
* 获得总页数 7:cmBkXm
*/ > 0kZ-M5
publicint getPageNum(){ Z}E.s@w
return(count - 1) / num + 1; l JR
} 6(FkcC$G
5VXI/Lw#
/** XLeQxp=
* 获得本页的开始编号,为 (p-1)*num+1 ^#Ruw?D
*/ OZ'=Xtbn
publicint getStart(){ 4)zHkN+
return(p - 1) * num + 1; , (Bo .(]
} )T_o!/\*|*
H fg2]N
/** ?f{--|V
* @return Returns the results. UUuB Rtau
*/
GW[g!66^
publicList<E> getResults(){ nB#m?hK
return results; <EHgPlQn
} j-% vLL/
m,TN%*U!
public void setResults(List<E> results){ <x^Ab#K"
this.results = results; (H/2{##
} W>*9T?
+li<y`aw0
public String toString(){ X/8CvY#n
StringBuilder buff = new StringBuilder f2abee
fC \Cx;q-
(); ^)| !nd
buff.append("{"); tE~OWjL
buff.append("count:").append(count); _(R1En1
buff.append(",p:").append(p); iFypKpHg~
buff.append(",nump:").append(num); [lmghI!
buff.append(",results:").append d5hYOhO[
D (>,#F
(results);
dkr[B'n
buff.append("}"); VN5UJ!$?J
return buff.toString(); AxsTB9/
} ^E)*i#."4
nNN~Z'bG
} e)#O-y
7jZE(|G-
mHiV};$