Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Jx_cf9{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 y6@0O%TDN
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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
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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 ,V'o4]H
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分页支持类: sJ\BF
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java代码: 7t3X)Ah
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package com.javaeye.common.util; ?M$.+V{a
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import java.util.List; Twh!X*uQ
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publicclass PaginationSupport { r}Ohkr
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publicfinalstaticint PAGESIZE = 30; gep;{G}
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privateint pageSize = PAGESIZE; du+y5dw
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privateList items; W"724fwu&
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privateint totalCount; t4{rb,
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privateint[] indexes = newint[0]; (VS5V31"
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privateint startIndex = 0; mCRt8rY;
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public PaginationSupport(List items, int so^lb?g
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totalCount){ WJ)z6m]
setPageSize(PAGESIZE); -\+s#kE:
setTotalCount(totalCount); CF&NFSti^
setItems(items); dL:-Y.?0M
setStartIndex(0); 85lCj-cs
} 9s_vL9u
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public PaginationSupport(List items, int =nz}XH%=
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totalCount, int startIndex){ g"Ljm7
setPageSize(PAGESIZE); +
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setTotalCount(totalCount); l|xZk4@_uE
setItems(items); _a_7,bk5
setStartIndex(startIndex); 0YaA `
} k $M]3}$U
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public PaginationSupport(List items, int n-5W*zk1
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); KN$}tCU
setTotalCount(totalCount); >oea{u
setItems(items); )S`jFQ1
setStartIndex(startIndex); yphS'AG
} ^L0d/,ik
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publicList getItems(){ X7[^s
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return items; f @8mS
} pa#d L!J
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publicvoid setItems(List items){ NxSu3e~PS
this.items = items; +U_=*"@|
} *+'x~a
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publicint getPageSize(){ Z:ni$7<.
return pageSize; 1[kMOp
} nYWvTvZ
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publicvoid setPageSize(int pageSize){ @vpf[j
this.pageSize = pageSize; HfcL%b%G8
} _C.BFE_p
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publicint getTotalCount(){ FSU ttg"
return totalCount; qs|mj}?
} rX*H)3F
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publicvoid setTotalCount(int totalCount){ *eIJwXE
if(totalCount > 0){ .R)PJc5^
this.totalCount = totalCount; x? ?pBhJH
int count = totalCount / ]DZE%
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pageSize; ktK_e
if(totalCount % pageSize > 0) p7);uF^O%
count++; ng:kA%!
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indexes = newint[count]; \2nUa
;
for(int i = 0; i < count; i++){ QF-LU
indexes = pageSize * u583_k%
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} SaC d0. h
}else{ 7uT:b!^f[
this.totalCount = 0; 76>7=#m0u'
} [v$0[IuY,
} a,3j,(3
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publicint[] getIndexes(){ T_X6Ulp
return indexes; 7Q7-vx
} :`E8Z:-R
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publicvoid setIndexes(int[] indexes){ kgy:Q'
this.indexes = indexes; 4VHqBQ4
} ;^La"m
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publicint getStartIndex(){ n"+[ :w4
return startIndex; d cLA1sN,
} k4,BNJt'Z
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publicvoid setStartIndex(int startIndex){ C|d\3S\(
if(totalCount <= 0) O@MGda9_;
this.startIndex = 0; /c"efnb!
elseif(startIndex >= totalCount) Ob}?zl@
this.startIndex = indexes !iH-#B-
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[indexes.length - 1]; PlF87j (
elseif(startIndex < 0) 8i|w(5m;
this.startIndex = 0; LUH"
else{ RG3l.jL
this.startIndex = indexes 3<k `+,'
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[startIndex / pageSize]; |fxA|/s[<
} RaWG w
} lrWV#`6!+
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publicint getNextIndex(){ ebS0qo[oLH
int nextIndex = getStartIndex() + QYa(N[~a
'; = f
pageSize; &ZghMq~
if(nextIndex >= totalCount) !lxTX
return getStartIndex(); \%/#x V
else o
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return nextIndex; *.~6S3}
} cC o`~7rE
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publicint getPreviousIndex(){ /CuXa%Ci^
int previousIndex = getStartIndex() - T<JwD[(
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pageSize; ymegr(9&K
if(previousIndex < 0) AZzuI*
return0; zG' "9kJx
else }Ow>dV?
return previousIndex; /&CmO>^e
} d)@<W1;
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} gzjR6uz
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抽象业务类 K=C!b?
java代码: o Y1';&BO9
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/** !(n4|Wd
* Created on 2005-7-12 V[}4L|ad
*/ Mva3+T
package com.javaeye.common.business; O(tX8P
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import java.io.Serializable; L KCb_9
import java.util.List; uch>AuF:
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import org.hibernate.Criteria; R)M_|ca
import org.hibernate.HibernateException; f6_];]yP
import org.hibernate.Session; /;7y{(o
import org.hibernate.criterion.DetachedCriteria; |J+(:{}~
import org.hibernate.criterion.Projections; !/^-;o7
import Sr&515
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org.springframework.orm.hibernate3.HibernateCallback; a-"k/P#
import "V>R9dO{"!
q}/WQ]p} <
org.springframework.orm.hibernate3.support.HibernateDaoS uKz,SqX
s:2|c]wQ#R
upport; t^xTFn
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import com.javaeye.common.util.PaginationSupport; 3I!?e!y3(
^ K7ic,{
public abstract class AbstractManager extends %.<H=!$
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HibernateDaoSupport { v~T7`
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privateboolean cacheQueries = false; p}|.ZkyN
@WQK>-=(3
privateString queryCacheRegion; Iq# ZhAk
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publicvoid setCacheQueries(boolean *\wp?s>-t
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cacheQueries){ '8fk+>M
this.cacheQueries = cacheQueries; $`8Ar,Xz`
} 7}GK%H-u
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publicvoid setQueryCacheRegion(String 6ns! ~g@
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queryCacheRegion){ Fi.aC;sx
this.queryCacheRegion = HxBm~Lcqy
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queryCacheRegion; &X|<@'933
} {TOmv
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publicvoid save(finalObject entity){ SFb{o<0 =
getHibernateTemplate().save(entity); rUlS'L;$"
} Cv>o.Bp|
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publicvoid persist(finalObject entity){ .fi/I
getHibernateTemplate().save(entity); 4<lQwV6=
} BaO1/zk
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publicvoid update(finalObject entity){ [L6w1b,
getHibernateTemplate().update(entity); kWlAY%
} /Y&02L%\3s
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publicvoid delete(finalObject entity){ cO\-
getHibernateTemplate().delete(entity); '`|AI:L
} FVB;\'/
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publicObject load(finalClass entity, 0l=+$&D
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finalSerializable id){ ?!=iu!J
return getHibernateTemplate().load }C
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(entity, id); 4g}FB+[u
} R#n%cXc|
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publicObject get(finalClass entity, Y7GF$}%UL
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finalSerializable id){ >tG+?Y'{
return getHibernateTemplate().get ?
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(entity, id); sBK <zR
} ]WUC:6x
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publicList findAll(finalClass entity){ *9 Q^5;y
return getHibernateTemplate().find("from [EY`am8[
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" + entity.getName()); <e)o1+[w
} a`E*\O'd
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publicList findByNamedQuery(finalString #5&jt@NS
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namedQuery){ kvGCbRC
return getHibernateTemplate {SZ % Xb o
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().findByNamedQuery(namedQuery); &[a Tw{2
} D-IR!js ]
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publicList findByNamedQuery(finalString query, :%JC^dV(
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finalObject parameter){ '
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return getHibernateTemplate dQgk.k
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().findByNamedQuery(query, parameter); p<`+sf}A:
} s$DrR
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publicList findByNamedQuery(finalString query, ?$z.K>S5
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finalObject[] parameters){ V (rr"K+
return getHibernateTemplate ~u&|G$1!0
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().findByNamedQuery(query, parameters); -$<O\5cAQ
} ~|Z'l%<Os
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publicList find(finalString query){ Y-~~,Yl~
return getHibernateTemplate().find G{x[uE2X&f
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(query); y69J%/c
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} ?@R")$
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publicList find(finalString query, finalObject DlyMJ#a
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parameter){ LS.r%:$mb
return getHibernateTemplate().find K(T\9J.
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(query, parameter); Ep ~wWQh
} 0{^H]Y
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public PaginationSupport findPageByCriteria Qbeeq6
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(final DetachedCriteria detachedCriteria){ "DSPPE&[c
return findPageByCriteria WxGSv#u
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Eff\Aq{
} F6S~$<
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint jN/C'\QL
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}
startIndex){ (A/0@f1#
return findPageByCriteria S<6k0b(,_3
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(detachedCriteria, PaginationSupport.PAGESIZE, noNm^hFL
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startIndex); (E($3t8
} :WXf.+IA
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public PaginationSupport findPageByCriteria tSv0" L
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(final DetachedCriteria detachedCriteria, finalint _$/
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pageSize, X QbNH~
finalint startIndex){ <%bw/
return(PaginationSupport) 3@5p"X
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getHibernateTemplate().execute(new HibernateCallback(){ Pg^h,2h
publicObject doInHibernate }X$l\pm
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(Session session)throws HibernateException { [@{0o+.]'H
Criteria criteria = <>4!XPo%J
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detachedCriteria.getExecutableCriteria(session); zp=!8Av
int totalCount = OM96`
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((Integer) criteria.setProjection(Projections.rowCount @R:#"
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()).uniqueResult()).intValue(); <fM>Yi5
criteria.setProjection E`p'L!z
\~"#ld(x7
(null); 6w#nkF
List items = x3p9GAd#
q#1X[A()
criteria.setFirstResult(startIndex).setMaxResults RR>G]#k
/jrY%C
(pageSize).list(); Etmo78e
PaginationSupport ps = %"7WXOv&z
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new PaginationSupport(items, totalCount, pageSize, w@N{@tG
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startIndex); L:U4N*
return ps; F+j O*F2h
} fuSq ={]
}, true); t.3\/
} 0 K3Hf^>m
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public List findAllByCriteria(final :|XCnK0
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DetachedCriteria detachedCriteria){ SWoEt1w
return(List) getHibernateTemplate bf98B4<
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().execute(new HibernateCallback(){ &d
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publicObject doInHibernate &|z544
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(Session session)throws HibernateException { +G!v!(Ob+
Criteria criteria = &,uC9$
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detachedCriteria.getExecutableCriteria(session); URw!7bTz
return criteria.list(); ZDlu1>Q
} PHkDb/HIx|
}, true); SL*DK.
} oYq,u@oM
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public int getCountByCriteria(final Qg>L,ZO
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DetachedCriteria detachedCriteria){ Rrz'(KSDw
Integer count = (Integer) U+!UL5k
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getHibernateTemplate().execute(new HibernateCallback(){ UT-ewXh
publicObject doInHibernate pYGYy'%A'
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(Session session)throws HibernateException { ~j}J<4&OvC
Criteria criteria = ]S]"`;Wh
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detachedCriteria.getExecutableCriteria(session); s*{mT6s+T
return }B*,mn2N
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criteria.setProjection(Projections.rowCount ftW{C1,U7
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()).uniqueResult(); M5rwoyn
} (+$ol'i
}, true); ;zm
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return count.intValue(); ):}Fu
} w&+\Wo;([b
} j/`Up
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用户在web层构造查询条件detachedCriteria,和可选的 iiehrK&T!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |?|K\UF(Y
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PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 )1BiEK`v
ps.getIndexes()得到分页索引的数组 >EeAPO4
ps.getTotalCount()得到总结果数 J{^n=X9M0J
ps.getStartIndex()当前分页索引 q1<Fg.-r
ps.getNextIndex()下一页索引 o>$|SU!a
ps.getPreviousIndex()上一页索引 8q{1E];:q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XzlIW&"uC
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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 t3Qm-J}wSB
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一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: sOjF?bCdO
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首先,为了实现分页查询,我封装了一个Page类: f^ywW[dF
java代码: /H.(d 4C
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/*Created on 2005-4-14*/ g8rp|MOH
package org.flyware.util.page; Kyyih|{
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/** K]%N-F>r
* @author Joa \kfcv
* $]Rl__;
*/ oMz/sL'u
publicclass Page { 5_PWGaQa
QId"Cl)3
/** imply if the page has previous page */ li1v 4
privateboolean hasPrePage; $:PF9pY(
nq),VPJi
/** imply if the page has next page */ pqkcf\
privateboolean hasNextPage; - a
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/** the number of every page */ )#)nBM2\
privateint everyPage; D l4d'&!
DxE^#=7iH;
/** the total page number */ XhQw+j~1.
privateint totalPage; bnAT,v{
2]?w~qjWm
/** the number of current page */ .vCY%0oE
privateint currentPage; =#
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L*kh?PS;
/** the begin index of the records by the current 1}i&HIr!b
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query */ Gr`MGQ,
privateint beginIndex; ?Ry%c6(}
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/** The default constructor */ j;1~=j])
public Page(){ ~E^yM=:h
ckH$E%j
} KK&<Vw|O\
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/** construct the page by everyPage *#9VC)Q
* @param everyPage %RCl+hOP.h
* */ ]+^;vc 1r
public Page(int everyPage){ s_S<gR
this.everyPage = everyPage; NqQM!B]
} xI/{)I1f
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/** The whole constructor */ { r<(t#
public Page(boolean hasPrePage, boolean hasNextPage, Q0
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int everyPage, int totalPage, ]7XkijNb
int currentPage, int beginIndex){ lpM>}0v
this.hasPrePage = hasPrePage; w^:V."}-$
this.hasNextPage = hasNextPage; oTplxF1
this.everyPage = everyPage; iBGSBSeL&
this.totalPage = totalPage; 3p?<iVE
this.currentPage = currentPage; =j'J
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this.beginIndex = beginIndex; r`&2-]
} h"RP>fZt
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/**
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* @return X/-
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* Returns the beginIndex. +d6Aw}*
*/ )vEHLp.
publicint getBeginIndex(){ I =tyQ`
return beginIndex; [*Aqy76Qa
} AHp830\
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/** RTPq8S"
* @param beginIndex q 2_N90u
* The beginIndex to set. %v`-uAy:
*/ h X>VVeIZ
publicvoid setBeginIndex(int beginIndex){ .b_0k<M!p
this.beginIndex = beginIndex; "2#-xOCO
} P/C+L[X=
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/** s{1Deek=
* @return @aqd'O
* Returns the currentPage. 4BduUH
*/ ) $l9xx[
publicint getCurrentPage(){ 7 BnenHD
return currentPage; $tt0D?$4
} m! '1$G
Z}'F"}QI
/** PcNfTB{
* @param currentPage #pDGaqeX
* The currentPage to set. c`$`0}
*/ +LI*!(T|lm
publicvoid setCurrentPage(int currentPage){ dm/\uE'l
this.currentPage = currentPage; w
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} NrI5uC7
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/** U Qi^udGFD
* @return syC"eH3{
* Returns the everyPage. QNa}M{5>h
*/ ].<sAmL^
publicint getEveryPage(){ 'wB Huq
return everyPage; Z$#ZYD
} fw:^Lyn9$
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/** JV?RgFy
* @param everyPage @aiLGwh
* The everyPage to set. {YKMQI^O/
*/ \9|]
publicvoid setEveryPage(int everyPage){ {Hp}F!X$
this.everyPage = everyPage; NBg>i7KQ
} -t~B@%
![P(B0Ct/
/** ~0^,L3M
* @return LA=>g/+i.X
* Returns the hasNextPage. |IcxegE
*/ ev: !,}]w
publicboolean getHasNextPage(){ dE}b8|</
return hasNextPage; DKVt8/vq
} n;k97>m${x
_E&vE5<-$
/** Er/5 ,
* @param hasNextPage 'MdE}
* The hasNextPage to set. 7 NB"oU^h%
*/ aWsKJo>j[#
publicvoid setHasNextPage(boolean hasNextPage){ o4[2`mT
this.hasNextPage = hasNextPage; 4gv XJK-
} H+#wj|,+\
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/** N;ecT@Ug
* @return ^<
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* Returns the hasPrePage. iUG/
*/ kz VI:
publicboolean getHasPrePage(){ hTtp-e`
return hasPrePage; hv:Z%D |S
} t`1]U4s&I
\IZ4( Z
/** !Ub?eJp
* @param hasPrePage -L 'K
* The hasPrePage to set. / ?[gB:s
*/ np\Q&
publicvoid setHasPrePage(boolean hasPrePage){ WJSHLy<a
this.hasPrePage = hasPrePage; 9MzkG87J
} ]xLb )Z
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/** q\HBAry
* @return Returns the totalPage. 0^lL,rC
* hYZ:" x
*/ Y&Lk4
publicint getTotalPage(){ "!/_h >
return totalPage; re7\nZ<\|
} =]xk-MY"|R
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/** K9M.+d4
* @param totalPage .@3u3i64'
* The totalPage to set. !BikF4Y1L&
*/ ?.A/E?Oc
publicvoid setTotalPage(int totalPage){ p;t!"I:`?
this.totalPage = totalPage; QRHm|f9_C
} qf=[*ZY
lg
} JHZo:Ad -&
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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 l(#Y8
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个PageUtil,负责对Page对象进行构造: }qdJ8K
java代码: >(ww6vk2
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/*Created on 2005-4-14*/ Jc?ssm\%
package org.flyware.util.page; nW%=k!''
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import org.apache.commons.logging.Log; EF=D}"E6pO
import org.apache.commons.logging.LogFactory; ~S>ba']
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/** *3
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* @author Joa a[cH@7W.#
* q<uLBaL_]r
*/ ye7&y4v+
publicclass PageUtil { ']Xx#U N
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privatestaticfinal Log logger = LogFactory.getLog K y2xWd8
wXGFq3`
(PageUtil.class); 1WN93SQ=
L Hz<=]?@
/** W}_}<rlF
* Use the origin page to create a new page HU+H0S~g
* @param page _rJSkZO
* @param totalRecords Z_~DTO2Qg
* @return FEmlC,%
*/ gj;G:;1m
publicstatic Page createPage(Page page, int uWj-tzu
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s)J[*w
totalRecords){ :Qp/3(g e
return createPage(page.getEveryPage(), :|Nbk58
F X2`p_
page.getCurrentPage(), totalRecords); Y1+lk^
} CHw_?#h
',j-n$Z^=
/** QaBXzf
* the basic page utils not including exception PQ1NQy8
:uDB3jN[
handler .T-p]9*p
* @param everyPage p&l:937
* @param currentPage .Awq(
* @param totalRecords becQ5w/~
* @return page "Oko|3
*/ oA@^N4PD
publicstatic Page createPage(int everyPage, int bLF0MVLM
HbDB?s<
currentPage, int totalRecords){ hzo,.hS's
everyPage = getEveryPage(everyPage); |YFlJ2w
currentPage = getCurrentPage(currentPage); l'\b(3JF
int beginIndex = getBeginIndex(everyPage, M?u)H&kEl
FCJ(D!
currentPage); |c/rHEZ
int totalPage = getTotalPage(everyPage, CnYX\^Ow
,jcp"-5#j
totalRecords); IpmREl$j
boolean hasNextPage = hasNextPage(currentPage, )yZE>>3-
QjU"|$
totalPage); }>U03aa!
boolean hasPrePage = hasPrePage(currentPage); "iGc'?/+
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returnnew Page(hasPrePage, hasNextPage, .&.CbE8K[
everyPage, totalPage, our5k
currentPage, O8o18m8UH
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beginIndex); 0O4mA&&!oK
} iNSJOS
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privatestaticint getEveryPage(int everyPage){ \0*LfVr;P
return everyPage == 0 ? 10 : everyPage; a$:N9&P
} c'R|Wyf
v4aGL<SO
privatestaticint getCurrentPage(int currentPage){ M6!brj\[|
return currentPage == 0 ? 1 : currentPage; 7^=jv~>wP
} ,u2<()`8D
p2^OQK
privatestaticint getBeginIndex(int everyPage, int B=|sLs`I
'WCTjTob/
currentPage){
GXVGU-br
return(currentPage - 1) * everyPage; >.4Sx~VH2
} kzXW<V9
R FiR)G ,
privatestaticint getTotalPage(int everyPage, int |-D.
N2J!7uoQ
totalRecords){ 2fB@zF
int totalPage = 0; S5TT
e?WR={
if(totalRecords % everyPage == 0) u*`GIRfWT
totalPage = totalRecords / everyPage; 9t1_"{'N1
else 74#@F{ w
totalPage = totalRecords / everyPage + 1 ; Lp=B? H
DYK|"@
return totalPage; ^XVa!s,d
} K?
k`U,
bmpB$@
privatestaticboolean hasPrePage(int currentPage){ K%B i8d
return currentPage == 1 ? false : true; iI0 'z=J
} rC16?RovQ@
l/LUwDI{
privatestaticboolean hasNextPage(int currentPage, ;@hP*7Lm
r1]^#&V;MC
int totalPage){ lc7]=,qyF
return currentPage == totalPage || totalPage == qa0Zgn5 q
H l@rS
0 ? false : true; b}*hodzF
} f *vziC<m
LBB[aF,Lr
bT}WJ2}
} [:qX3"B
z16++LKmM
m>_'f{&u
E?uv&evPK7
7Wu2gky3
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。 (%Rs&/vU~
<0m;|Ai'W
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 IYPLitT
/xzL!~g`6<
做法如下: Wwz{98,K
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 PdZSXP4;k
P.Bk-#}$
的信息,和一个结果集List: _?"J.i
java代码: 8ZDq
KQ1;
j3><J
AdNsY/ Y(
/*Created on 2005-6-13*/ 0% /M& N
package com.adt.bo; AXCJFqk;
gNeCnf#Xa
import java.util.List; ~nQb;Bdh%
:`K;0`C+
import org.flyware.util.page.Page; .z"[z^/uF
:lAR;[WFS
/** YAog;QL
* @author Joa 6FE[snw
*/ tdm /U
publicclass Result { VbjFQ@[l!
M<nn+vy`
private Page page; ~xCy(dL^}
~U|te _l
private List content; @WmB0cc_
a/ZfPl0Ns[
/** '};Xb|msU
* The default constructor g;pFT
*/
ulQE{c[
public Result(){ R+\5hI@ >i
super(); .o>QBYpTw/
} RwE]t$T/
-l",!sV
/** ;p/@tr9
* The constructor using fields 8c9_=8vw
* >\'yj|
U,
* @param page ~BC5no
* @param content 8HzEH-J
*/ aF:I]]TfK~
public Result(Page page, List content){ 1\McsX4
this.page = page; G9
!1Wzs
this.content = content; }7V/(K
} ;8@A7`^
,oCr6 ]
/** i<
ih :
* @return Returns the content. (.c?)_G,
*/ yVL~SH|
publicList getContent(){ [;(|^0
return content; `{ /tx!
} y&
)z\8
>g?,BK@
/** Q_dFZ
* @return Returns the page. P|\,kw>l
*/ Y4_i=}\*vf
public Page getPage(){ p7*\]HyE)
return page; O@[q./VV,
} Q~9:}_@
U+K_eEI0_I
/** Kl*##qw!
* @param content 9u9#&xx
* The content to set. "x{S3v4Rb5
*/ /4|qfF3
public void setContent(List content){ FUDMaI
this.content = content; G
-;Yua2\
} ]?kf;A@
' :Te#S
/** 'j.{o
* @param page Rk'Dd4"m,
* The page to set. P=h2Z,2
*/ pY2nv/
publicvoid setPage(Page page){ o5)U3U1|
this.page = page; eq"~by[Uq
} A >x{\
} )P$
IXA\
^xq%P2s0
0q/g:"|j
Hi?],5,/
.G^.kg ,
2. 编写业务逻辑接口,并实现它(UserManager, Cc=`:ED+
9 Hm!B )Y
UserManagerImpl) bC&_OU:
java代码: _+UD>u{
MPT[f
s?=J#WV1y
/*Created on 2005-7-15*/ ,3^N_>d$W
package com.adt.service; Tj>~#~
$N+azal+y
import net.sf.hibernate.HibernateException; >%7iL#3%
*bZV4}
import org.flyware.util.page.Page; %1#5
7-
N%`ikdaTd
import com.adt.bo.Result; D3I;5m`_
$
@^n3ZQ4
/** JK_sl>v.7
* @author Joa =Y89X6
*/ s,0,w--=
publicinterface UserManager { N^)L@6
_$1W:!f4
public Result listUser(Page page)throws ><$hFrR!
f~E'0f_
HibernateException; M'*
Y
&
K7+V
} qwnC{
9#1lxT4%
cP(/+
/9
gvz&ppcG
sB /*gO
java代码: Fm*O&6W\@A
s7=]!7QGS!
n2$*Z6.G
/*Created on 2005-7-15*/ NC0x!tJ#7
package com.adt.service.impl; J7S
a?@j`@]ZR~
import java.util.List; ]` 3;8,
:U?Kwv8 s
import net.sf.hibernate.HibernateException; MvObx'+
TC ^EyjD
import org.flyware.util.page.Page; W|~Ehg
import org.flyware.util.page.PageUtil; BjJ+~R
A`IE8@&Z'
import com.adt.bo.Result; >?I[dYzut
import com.adt.dao.UserDAO; =`g+3
O;<
import com.adt.exception.ObjectNotFoundException; n;4`IK|
import com.adt.service.UserManager; eja_+`cJ
z$;z&X$j
/** ~g)gXPjke
* @author Joa 'kPShZS$b
*/ M,:GMO:?a
publicclass UserManagerImpl implements UserManager { ?-J\~AXL
w,D(zk$
private UserDAO userDAO; ;Cm%<vW4!
7LKNEll
/** 'R?;T[s%
* @param userDAO The userDAO to set. +K]kGF
*/ &rk/ya[
publicvoid setUserDAO(UserDAO userDAO){ l3-;z)SgH
this.userDAO = userDAO; H7*/
} +ImPNwrY
f0}+8JW5h
/* (non-Javadoc) Fb
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* @see com.adt.service.UserManager#listUser ^#p Su
z1_\P) M
(org.flyware.util.page.Page) BY72 fy#e
*/ ?<
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public Result listUser(Page page)throws !bS:!Il9=
}JoCk{<31
HibernateException, ObjectNotFoundException { ~8RN
int totalRecords = userDAO.getUserCount(); (Z;-u+ }.
if(totalRecords == 0) &p`RKD
throw new ObjectNotFoundException 5
J61PuH
Sr/"'w;
("userNotExist"); QVm3(;&'
page = PageUtil.createPage(page, totalRecords); g#T8WX{(V
List users = userDAO.getUserByPage(page); Fz~-m# Ts
returnnew Result(page, users); 1\TXb!OtL
} 5L%A5C&|
A9!%H6
} ?,O{,2}
G(EiDo&
FhHcS>]:.
V)oUSHillH
98x]x:mgI_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 c 7E=1*C<
Z>{3t/`
询,接下来编写UserDAO的代码: 7ae8nZ3&
3. UserDAO 和 UserDAOImpl: t[XxLG*
java代码: ]]J2#mN:n
ehPrxIyC
eI/9uR%
/*Created on 2005-7-15*/ MyXgp>?~T
package com.adt.dao; S1.w^Ccy
49E<`f0
import java.util.List; wWQv]c%
SoI"a^fY
import org.flyware.util.page.Page; Kzfa4C
)#N)w5DU
import net.sf.hibernate.HibernateException; pZ}4'GnZI
RU|{'zC\v
/** }PTYNidlR
* @author Joa RHZ5f0b4L
*/ ri<E[8\
publicinterface UserDAO extends BaseDAO { 1D sgU6"
7loIX Qw
publicList getUserByName(String name)throws !'Q/9%g
|<t"O
HibernateException; pdX%TrM+[:
Pq ZMuUd
publicint getUserCount()throws HibernateException; Es/\/vF7]D
DJ2EV^D+P
publicList getUserByPage(Page page)throws iP6$;Y{ZA
?kqo~twJ
HibernateException; ,W;\6"Iwx'
wO;\,zU
} :,X,!0pWRp
&9g4/c-?$
k4FxdX
u[$ \
az7
t9685s
java代码: tIR"y:U+
( 6|S42
XbsEO>_Z'A
/*Created on 2005-7-15*/ {7LO|E}7
package com.adt.dao.impl; jO)UK.H#
&`[y] E'
import java.util.List; </3Shq
]([:"j
import org.flyware.util.page.Page; 4mq+{c0
2"*7HS
import net.sf.hibernate.HibernateException; K+5S7wFDZ
import net.sf.hibernate.Query; YKk?BQ"
c
%w
h
import com.adt.dao.UserDAO; /ldE (!^n
dq}60
/** fOs"\Y4
* @author Joa ?4GI19j
*/ X YO09#>&
public class UserDAOImpl extends BaseDAOHibernateImpl 'yu M=Pb
:_E
q(r
implements UserDAO { x2(!r3a
.>NhC"
/* (non-Javadoc) Yj99[
c#]
* @see com.adt.dao.UserDAO#getUserByName z;yb;),
!r]elX
(java.lang.String) &(UVS0=Dp,
*/ K<'L7>s3lA
publicList getUserByName(String name)throws |-GmW SK_
mZDL=p
HibernateException { yNMnByg3?
String querySentence = "FROM user in class *u^N_y
b0|q@!z>
com.adt.po.User WHERE user.name=:name"; i>#[*.|P
Query query = getSession().createQuery qfE>N?/
=LEKFXqM
(querySentence); !g{9]"Z1T
query.setParameter("name", name); -h+=^,
return query.list(); O)NEt
} VDq4n;p1
k$1ya7-@
/* (non-Javadoc) H. U wM
* @see com.adt.dao.UserDAO#getUserCount() W|XTa
*/ E#?*6/
publicint getUserCount()throws HibernateException { S(<r-bV<
int count = 0; %upnXRzw
String querySentence = "SELECT count(*) FROM EkS7j>:
q|,cMPS3
user in class com.adt.po.User"; HO%atE$>
Query query = getSession().createQuery pcwkO
mVFz[xI
(querySentence); $xqI3UaX
count = ((Integer)query.iterate().next <Hw)},_*
%"Tn=fZIF
()).intValue(); 'wB6-
return count; 7A'd55I4
} rV.04m,
JbN@AX:%
/* (non-Javadoc) ~"F83+RDe
* @see com.adt.dao.UserDAO#getUserByPage CMn&1
|d}f\a`
(org.flyware.util.page.Page) dXR70/
*/ .zxP,]"l
publicList getUserByPage(Page page)throws aVsA5t\zi
ip6$Z3[)
HibernateException { oo sbf#V
String querySentence = "FROM user in class _):V7Zv
Pl(+&k`}
com.adt.po.User"; n46A
Query query = getSession().createQuery [C 1o9c!
^M36=~j
(querySentence); 'ap<]mf2
query.setFirstResult(page.getBeginIndex()) rF C 6"_
.setMaxResults(page.getEveryPage()); O9y4.`a"
return query.list(); Vp{e1xpY
} Khd"
(`h$+p^-y
} *{/
ww9fT
vowU+Y
wBlfQ
w-N
{*WJ"9ujp]
Omy4Rkj8bh
至此,一个完整的分页程序完成。前台的只需要调用 b=[gK|fu
`;Qw/xl_N
userManager.listUser(page)即可得到一个Page对象和结果集对象 t<S]YA~N'
W'2T7ha Es
的综合体,而传入的参数page对象则可以由前台传入,如果用 za{z2#aJ
+76{S_CZ
webwork,甚至可以直接在配置文件中指定。 ds@X%L;_
g=w,*68vuy
下面给出一个webwork调用示例: A$*#n8,
java代码: O%RkU?ME
jSa9UD
TS0x8,'$q
/*Created on 2005-6-17*/ 0].x8{~o
package com.adt.action.user; (bEX"U-
1n}q6oa=
import java.util.List; c 32IO&W4
.Cv0Ze
import org.apache.commons.logging.Log; S;a'@5
import org.apache.commons.logging.LogFactory; K"~Tk`[0Q
import org.flyware.util.page.Page; h%'4V<V
J[E_n;d1
import com.adt.bo.Result; {z)&=v@
import com.adt.service.UserService; u{Jv6K,
import com.opensymphony.xwork.Action; cI}qMc
O^fg~g X
/** "-aak )7w
* @author Joa yKE[,"
*/ ,>" rcd
publicclass ListUser implementsAction{ CNwYQe-i
'u@_4wWp
privatestaticfinal Log logger = LogFactory.getLog 5Z2E))UU
~" \qX+
(ListUser.class); 08)X:@ w?
mmk]Doy?#
private UserService userService; [Xp{ztGE
HSq.0vYl6
private Page page; [$; \1P/
=%u\x=u|
privateList users; `J*~B
L<'8#J[_5
/* 97"dOi!Wh
* (non-Javadoc) =+um:*a.
* a*4"j2j v
* @see com.opensymphony.xwork.Action#execute() w)x`zVwO
*/ 3L2@C%
publicString execute()throwsException{ .Q'/e>0
Result result = userService.listUser(page); Wxjv=#3
page = result.getPage(); en\shc{R]`
users = result.getContent(); :00 #l]g0q
return SUCCESS; JTT"t@__
} C;m 7~R
mKWfRx*UdG
/** !3~VoNh,
* @return Returns the page. bu`8QQ"C
*/ Z4S0{:XY
public Page getPage(){ eIVCg-l}
return page; X8!=Xjl)
} @NBWNgBv
*2MM
/** g8+w?Zn}
* @return Returns the users. U3SF'r8
*/ ">b~k;M?
publicList getUsers(){ >FtW~J"X
return users; C N9lK29F)
} m9*Lo[EXO
\EH:FM}l,
/** 8?qEv,W
* @param page eF5?4??
* The page to set. RusC5\BUX
*/ sA18f2
publicvoid setPage(Page page){ tT7< V{i4
this.page = page; Zf~[4Eeb
} z`gdE0@;d3
QusEWq)}<
/** StUiL>9T#
* @param users k;V4%O
* The users to set. >`rK=?12<
*/ }qUNXE@
publicvoid setUsers(List users){ 6bL+q`3>
this.users = users; 7?6?`no~JJ
} )k5lA=(Yr+
/a7tg+:
/** ,e"A9ik#
* @param userService .y7&!a35
* The userService to set. w, 0tY=h6
*/ )"7hyW 5
publicvoid setUserService(UserService userService){ KZ
ezA4
this.userService = userService; VdpkE0
} GD1=Fb"&)
} K
GlO;Q~7
6T6 S9A*nT
hjiU{@q
oOk.Fq
B`Q.<Lqu
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, '8~cf
o l67x
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 1jZ:@M:
rI&GM
|
么只需要: rl)(4ad=
java代码: 9GnNL I{
riI0k{
Z<a6U 3
<?xml version="1.0"?> *[*E|by
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork p},6W,f
iKB8V<[\T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +Q, 0kv
LV:oNK(
1.0.dtd"> ^RkHdA
@aR! -}
<xwork> *AXu_^^
gF%lwq
<package name="user" extends="webwork- L1u
Auhw(b>}TW
interceptors"> w<_.T#
y(|6`
<!-- The default interceptor stack name Gy[;yLnX
$Aww5G5e
--> z602(mxGg
<default-interceptor-ref JH2?^h|{
cL*D_)?8
name="myDefaultWebStack"/> ssW+'GD
6w K=
<action name="listUser" -tT{h4
,=lMtW
class="com.adt.action.user.ListUser"> ^DHFP-G?e
<param L>{E8qv>w
[!{*)4$6
name="page.everyPage">10</param> 64}Oa+*s
<result M;W{A)0i1
9\*xK%T+
name="success">/user/user_list.jsp</result> CogLo&.
</action> =mCUuY#
j' -akXo<
</package> JnCY O^Qj
.LafP}%
</xwork> f+0dwlIlC$
iR4CY-
9>psQ0IRvr
MoA2Cp;8X
GFvZdP`s4
,
j,[4^
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 >H@
dgb
}M
f}gCEW
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。 I"3Qdi
?)Lktn9%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 TJ`E/=J!
hC}A%_S
WX
79V
/-4i"|
Z5Ao3O@
我写的一个用于分页的类,用了泛型了,hoho ;^:~xJFx|
N`y!Km
java代码: \~xsBPX+x
p<'mc|hGq
g=pz&cz;>\
package com.intokr.util; tjOfekU
8_f0P8R!y
import java.util.List; mT@UQCG
@Th.=
/** '2z o
* 用于分页的类<br> dk({J
* 可以用于传递查询的结果也可以用于传送查询的参数<br> t=S94^g
* <PW*vo9v
* @version 0.01 |x{:GWq
* @author cheng m&,d8Gss^
*/ 8,Yc1
public class Paginator<E> { F$ Us! NN
privateint count = 0; // 总记录数 cR$2`:e
privateint p = 1; // 页编号 BmUEo$w
privateint num = 20; // 每页的记录数 4cJ^L <
privateList<E> results = null; // 结果 7*^\mycv
sx8mba(
/** fJOU1%
* 结果总数 u 8U>R=M
*/ P%pB]d.qpi
publicint getCount(){ H` Q_gy5Z(
return count; +Qu~UK\
}
-N5r[*>
S=[K/Kf-
publicvoid setCount(int count){ A`#v-
this.count = count; /lttJJDU
} 8c+i+gp!
EPI mh
/** Sijwh1j*V
* 本结果所在的页码,从1开始 4,FkA_k
* %S>lPt
* @return Returns the pageNo. ]S,I}NP
*/ \I#lLP
publicint getP(){ UN|"D]>/
return p; ]ZO^@sH
} !i_5XcH
lhQ*;dMj%"
/** aChY5R
* if(p<=0) p=1 lqqY5l6j
* ReKnvF~
* @param p 8XX,(k_b
*/ K"Nq_Ddwd
publicvoid setP(int p){ :Iwe> ;}
if(p <= 0) aU4'_%Y@
p = 1; HtY\!_Ea
this.p = p; bvEk.~tC'
} *KxV;H8/
}E8 Y,;fTD
/** I$qL=
* 每页记录数量 a<!g*UVL0M
*/ F8b*Mt}p
publicint getNum(){ `mw@"
return num; W@"M/<r@/
} yuFuYo&[?v
?ZlwRjB\
/** P;hjr;
* if(num<1) num=1 3m7$$N|
*/ _sZ/tU@_-K
publicvoid setNum(int num){ F1Egcx/$V
if(num < 1) t47 f$gq
num = 1; 34JkB+#a
this.num = num; c)@M7UK[
} 4CX *
S)g5Tu)
/** L=Dx$#|
* 获得总页数 MrOW&7
*/ .&r]
?O
publicint getPageNum(){ n0Ze9W+<
return(count - 1) / num + 1; J9poqp@`MG
} HaB=nLAT
n{4&('NRFP
/** P[XE5puC
* 获得本页的开始编号,为 (p-1)*num+1 tm+}@CM^.
*/ !nuXK
publicint getStart(){
Q:_pW<^
return(p - 1) * num + 1; RG*Nw6A
} s%4)}w;z
.fo.mC@a
/** YqNhD6
* @return Returns the results. /8W}o/,s5
*/ dP)8T
publicList<E> getResults(){ pVbX#3
return results; h3@mN\=h'
} n=rPFpRLF
*%Gy-5hM
public void setResults(List<E> results){ fM
S-
this.results = results; 0pkU1t~9
} Mv4JF(,S
Qt>yRt
public String toString(){ 8VMq>-
StringBuilder buff = new StringBuilder .V/TVz!b
^o?.Rph|i]
(); ctt5t
buff.append("{"); ;C{2*0"H|
buff.append("count:").append(count); u=rY
buff.append(",p:").append(p); S'E6#
buff.append(",nump:").append(num); 3kYUO-qw
buff.append(",results:").append hC6$>tl
)%,bog(x
(results); x(mY$l,il
buff.append("}"); krz@1[w-j
return buff.toString(); hCr7%`
} }s{zy:1O
qx_+mCZ
} vj{h*~
Ap}:^k5{
p[Q