Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 lSBu,UQP
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }ssL;q
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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 pI}6AAs}Z
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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 vGD D
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分页支持类: 'v%v*Ujf[
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java代码: _p0G8
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package com.javaeye.common.util; p
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import java.util.List; #Wely~
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publicclass PaginationSupport { "(vm0@8><
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publicfinalstaticint PAGESIZE = 30; i:x<Vi
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privateint pageSize = PAGESIZE; B }
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privateList items; DVw 04ay%
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privateint totalCount; 4Vv$bbu+
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privateint[] indexes = newint[0]; g.COKA
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privateint startIndex = 0; iV.j!H7o
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public PaginationSupport(List items, int :F
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totalCount){ 1U8/.x|
setPageSize(PAGESIZE); >44,Dp]
setTotalCount(totalCount); 8WLBq-]G
setItems(items); 3W55m@w
setStartIndex(0); a+P^?N
} M`,`2I A
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public PaginationSupport(List items, int 077 wk
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totalCount, int startIndex){ 7t|011<
setPageSize(PAGESIZE); sEcg;LFp
setTotalCount(totalCount); pZ&?uo67_
setItems(items); Df=Xbf>jt9
setStartIndex(startIndex); HA3d9`
} ~jMfm~
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public PaginationSupport(List items, int u*8x.UE8C0
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totalCount, int pageSize, int startIndex){ m-HBoN
setPageSize(pageSize); 7X/KQ97
setTotalCount(totalCount); ZW`wA2R0
setItems(items); m&k l_f7
setStartIndex(startIndex); `tJ"wpCf6
} Wrs6t
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publicList getItems(){ H1hADn
return items; Z1R{'@Y0Z
} aa/_:V@$~
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publicvoid setItems(List items){ f<*-;
this.items = items; xGt>X77
} "T' QbK0
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publicint getPageSize(){ D[<~^R;*
return pageSize; epxbTJfc
} bs?&;R.5
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publicvoid setPageSize(int pageSize){ DQ%(X&k
this.pageSize = pageSize; 5@`dKFB5
} $Sc;
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publicint getTotalCount(){ `W'S'?$
return totalCount; m4RiF
} KfV&7yi
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publicvoid setTotalCount(int totalCount){ M6"a
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if(totalCount > 0){ {{ +8oRzY
this.totalCount = totalCount; #EIcP=1m4
int count = totalCount / \>c1Z5H>
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pageSize; iKA qM{(
if(totalCount % pageSize > 0) FUs57
V
count++; PQ(/1v
indexes = newint[count]; t^8|t(Lq
for(int i = 0; i < count; i++){ "hLmwz|a
indexes = pageSize * ~otV'= /my
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i; c[;=7-+
} o~ReeZ7)Zg
}else{ o3a%u(
this.totalCount = 0; a_k~z3wG
} -\V;Gw8mD
} Zxn>]Z_
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publicint[] getIndexes(){ j:xm>X'
return indexes; uF<\|y rFt
} YL9Tsw
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publicvoid setIndexes(int[] indexes){ vfOG(EkG.?
this.indexes = indexes; T,5(JP(h3
} NU.YL1
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publicint getStartIndex(){ z i3gE$7
return startIndex; Jp +h''t
} Ql?>,FZ
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publicvoid setStartIndex(int startIndex){ F{F SmUxzK
if(totalCount <= 0) JwcC9
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this.startIndex = 0; ky@DH(^>
elseif(startIndex >= totalCount) `a]feAl
this.startIndex = indexes CAbT9Wz&
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[indexes.length - 1]; $QJ,V~
elseif(startIndex < 0) 4\(|V
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this.startIndex = 0; \vp^[,SI
else{ dyuT-.2
this.startIndex = indexes 7*g'4p-
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[startIndex / pageSize]; okLheF
} >3)AO04=;
} d2tJ=.DI
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publicint getNextIndex(){ >on' y+
int nextIndex = getStartIndex() + q]OgT4ly
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pageSize; iS}~e{TP/
if(nextIndex >= totalCount) f^ 6da6Z
return getStartIndex(); );L +)UV
else Z~HLa
return nextIndex; 4/E>k <MA
} -k}&{v
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publicint getPreviousIndex(){ -|`E'b81
int previousIndex = getStartIndex() - f4&k48Ds
},vVc/
pageSize; Y$N D
if(previousIndex < 0)
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return0; F/0x`l
else #5mnSky+s
return previousIndex; A?Gk8
} S")*~)N@
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} 6Y/TqI[
6|ENDd[
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抽象业务类 G?v]|wdI
java代码: q{RT~,%
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/** -mqTlXM
* Created on 2005-7-12 CB>O%m[1
*/ 7A46?kfu
package com.javaeye.common.business; J)_IfbY
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import java.io.Serializable; MI*@^{G
import java.util.List; T.iVY5^<
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import org.hibernate.Criteria; mY/x|)MmM
import org.hibernate.HibernateException; #GA6vJ4^s
import org.hibernate.Session; Ar1X
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import org.hibernate.criterion.DetachedCriteria; XOd
import org.hibernate.criterion.Projections; ~{BR~\D
import s&Ml1A :
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org.springframework.orm.hibernate3.HibernateCallback; Ol1P
import +u'y!@VV
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org.springframework.orm.hibernate3.support.HibernateDaoS #;Z+X)
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upport; (S
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import com.javaeye.common.util.PaginationSupport; jGKas I`
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public abstract class AbstractManager extends ulxy 4] h
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HibernateDaoSupport { XyE%<]
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privateboolean cacheQueries = false; iV8O<en&i
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privateString queryCacheRegion; h6C:`0o
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publicvoid setCacheQueries(boolean -
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cacheQueries){ 7P7d[KP<
this.cacheQueries = cacheQueries; i 79;;9M
} 8WL*Pr1I
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publicvoid setQueryCacheRegion(String u4;#~##
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queryCacheRegion){ (S#nA:E
this.queryCacheRegion = [wR x)F"
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queryCacheRegion; d@,3P)?
} &P3ep[]j
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publicvoid save(finalObject entity){ Pg/$N5->
getHibernateTemplate().save(entity); zoI0oA
} 9Z;"9$+M
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publicvoid persist(finalObject entity){ Aq"<#:
getHibernateTemplate().save(entity); 30nR2mB
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} wf=M|
#}_
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publicvoid update(finalObject entity){ g7nqe~`{
getHibernateTemplate().update(entity); 6qzy eli
} 6I,4 6 XZ-
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publicvoid delete(finalObject entity){ #ZvDf5A
getHibernateTemplate().delete(entity); T*8rR"
} Uv"O'Z
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publicObject load(finalClass entity, W!
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finalSerializable id){ u+/1ryp
return getHibernateTemplate().load sFWH*kdP?
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(entity, id); t+`>zux5(T
} @2Ca]2,4
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publicObject get(finalClass entity, NY!"?Zko
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finalSerializable id){ [n{c, U
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return getHibernateTemplate().get A *_ |/o
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(entity, id); q'~F6$kv5
} h`:f
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publicList findAll(finalClass entity){ li
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return getHibernateTemplate().find("from p^ojhrr
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" + entity.getName()); }|!9aojr
} /~B\1
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publicList findByNamedQuery(finalString Fi!XaO
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namedQuery){ |g}~7*+i
return getHibernateTemplate #X?#v7i",D
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().findByNamedQuery(namedQuery); G'qGsKf\
} ;]+p>p-#
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publicList findByNamedQuery(finalString query, ??tNMr5{[
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finalObject parameter){ E A8>{}Z*
return getHibernateTemplate L-v-KO6
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().findByNamedQuery(query, parameter); Q!_@Am"h
} mfpL?N
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publicList findByNamedQuery(finalString query, pJpTOq\h
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finalObject[] parameters){ a="\?L5
return getHibernateTemplate 4RYvI!
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().findByNamedQuery(query, parameters); .*>pD/
} v)AadtZ0d
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publicList find(finalString query){ gcNpA?mC|u
return getHibernateTemplate().find >'GQB
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(query); -w#Hy>E
} ?c!W*`yP
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publicList find(finalString query, finalObject ahJu+y
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parameter){ |zaYIVE[
return getHibernateTemplate().find e//q`?ys
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(query, parameter); `aw5"ns^V
} YPY'[j(p`n
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public PaginationSupport findPageByCriteria ~^u#Q\KE"
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(final DetachedCriteria detachedCriteria){ x\m?* 5p
return findPageByCriteria r-+S^mOE]
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); a' pJg<
} S@'yuAe*G
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public PaginationSupport findPageByCriteria ~wdKO7fs
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(final DetachedCriteria detachedCriteria, finalint H#+?)<UQ
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startIndex){ %G%D[ i]
return findPageByCriteria $_P*Bk)
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(detachedCriteria, PaginationSupport.PAGESIZE, #g6*s+Gm
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startIndex); }N6r/
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} d^Jf(NE0Yo
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public PaginationSupport findPageByCriteria ,n&e,I
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(final DetachedCriteria detachedCriteria, finalint %bs~%6)
Z}
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pageSize, 0f<$S$~h
finalint startIndex){ ee=d*)
return(PaginationSupport) <&$:$_ah
mq(*4KFWJ2
getHibernateTemplate().execute(new HibernateCallback(){ ]ZjydQjo)
publicObject doInHibernate -'9sn/
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(Session session)throws HibernateException { IO4 8sV }
Criteria criteria = < x==T4n/
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detachedCriteria.getExecutableCriteria(session); Lb>UraUvL
int totalCount = $M(ZKS3,j
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((Integer) criteria.setProjection(Projections.rowCount FojsI<
#
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()).uniqueResult()).intValue(); v^;%Fz_Dr
criteria.setProjection ~e)`D nJ
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(null); {U,q!<@mq
List items = 5l&9BS&
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criteria.setFirstResult(startIndex).setMaxResults EZ.|6oug\
y_=},a
(pageSize).list(); 6tBh`nYB=
PaginationSupport ps = ^?5[M^
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new PaginationSupport(items, totalCount, pageSize, >**7ck
h xCt[G@
startIndex); H#LlxD)q
return ps; $ 4&
)
} U6pG
}, true); )ww#dJn
} abVz/R/o
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public List findAllByCriteria(final }4; \sY
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DetachedCriteria detachedCriteria){ o$=D`B
return(List) getHibernateTemplate iA^GA8dn
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().execute(new HibernateCallback(){ b\U p(]
publicObject doInHibernate f0^DsP
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(Session session)throws HibernateException { B tZycI
Criteria criteria = 8u401ddg
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detachedCriteria.getExecutableCriteria(session); qOV6Kh)
return criteria.list(); pErre2fS
} ,MtN_V-
}, true); {M5[gr%
} W+'|zhn
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public int getCountByCriteria(final \*5_gPj!d
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DetachedCriteria detachedCriteria){ j>5D4}*]f
Integer count = (Integer) %Tn0r|K
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getHibernateTemplate().execute(new HibernateCallback(){ )T=cd
publicObject doInHibernate ;34 m!\N5
vB :_|B
(Session session)throws HibernateException { ,DHiM-v
Criteria criteria = 4;*o}E
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detachedCriteria.getExecutableCriteria(session); Wa8?o~0"L
return @"6dq;"
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criteria.setProjection(Projections.rowCount o+H;ZGT5H
{ws:g![
()).uniqueResult(); "v"w ER?
} 483BrFV
}, true); \9*,[mvC
return count.intValue(); qw!_/Z3[
} 7,sslf2%K
} FE)L?
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用户在web层构造查询条件detachedCriteria,和可选的 `g;`yJX<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 3MR4yw5v
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PaginationSupport的实例ps。 _VeZlk7k
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ps.getItems()得到已分页好的结果集 Hw1<!Dyv
ps.getIndexes()得到分页索引的数组 f$lf(brQ:
ps.getTotalCount()得到总结果数 X676*;:!.
ps.getStartIndex()当前分页索引 -`mHb
ps.getNextIndex()下一页索引 8?lp:kM
ps.getPreviousIndex()上一页索引 UqaLTdYG
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 y%X{[F
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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 <bPn<QI
@
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一下代码重构了。 pZu2[
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我把原本我的做法也提供出来供大家讨论吧: ,qj
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首先,为了实现分页查询,我封装了一个Page类: ,FvBZ.4c3=
java代码: :
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/*Created on 2005-4-14*/ Mh04O@"
package org.flyware.util.page; &></l| hY
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/** Z7<N<
* @author Joa : QK )Ym
* qwlIz/j
*/ 7|A9
publicclass Page { FK
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/** imply if the page has previous page */ ]j.??'+rg
privateboolean hasPrePage; \0'7p-T6
zV(F9}^
/** imply if the page has next page */ /dU-$}>ZI
privateboolean hasNextPage; 69U[kW&
|2 2~.9S
/** the number of every page */
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privateint everyPage; A$K>:Tt>
(fc
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/** the total page number */ r-#23iT.~
privateint totalPage; f)xHSF"
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/** the number of current page */ l65-8
privateint currentPage; TI{W(2O *
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/** the begin index of the records by the current T{1Z(M+
i"}%ib*X
query */ %KxL{HY
privateint beginIndex; .".xNHR#
lW! U:
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/** The default constructor */ "(uEcS2<
public Page(){ &J~vXk:
!
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} ;dt&*]wA
_y Q*
/** construct the page by everyPage Pdc- 3
* @param everyPage @\,WJmW
* */ V j\1HQ
public Page(int everyPage){ .6Swc?
this.everyPage = everyPage; &8R %W"<K
} g{&a|NU^
H\tz"<*``
/** The whole constructor */ B_w;2ZuA
public Page(boolean hasPrePage, boolean hasNextPage, zi~_[l-
"Jw6.q+
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int everyPage, int totalPage, Dp
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int currentPage, int beginIndex){ _w+ix9Fr?
this.hasPrePage = hasPrePage; 2| u 'J
this.hasNextPage = hasNextPage; 9/OB!<*V|
this.everyPage = everyPage; r2A(GUz
this.totalPage = totalPage; m2[q*k]AtS
this.currentPage = currentPage; v~>^c1:
this.beginIndex = beginIndex; =F2e*?a3
} FL5u68
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/** e[fzy0
* @return )Yvf9dl
* Returns the beginIndex. $ig%YB
*/ .W{\wkn
publicint getBeginIndex(){ .d:sQ\k~=
return beginIndex; B mq7w,L.
} " &B/v"nj
WDr'w'
/** ^Z7])arA
* @param beginIndex ^7C?yC
* The beginIndex to set. 0Y#S2ty
*/ #87:Or1
publicvoid setBeginIndex(int beginIndex){ *S.R#4w
this.beginIndex = beginIndex; uX*H2"A
} <>,V>k|
T)Byws
/** [xT2c.2__J
* @return noiUi>G;:
* Returns the currentPage. 6 flc
*/ \HFeEEKH
publicint getCurrentPage(){ g+gHIb7{
return currentPage; (q+U5Ls6
} 0eY$K7
U
*V(TNLIh;
/** LGq}wxq
* @param currentPage EJ P##eGx
* The currentPage to set. olzP=08aaV
*/ HVzG }r(J
publicvoid setCurrentPage(int currentPage){ :&Xy#.un
this.currentPage = currentPage; CK1Xdyf_S
} 6y&d\_?Y
'|n-w\
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/** Hw8`/'M=%5
* @return cF_hU"
* Returns the everyPage. b'`8$;MII
*/ Gu Msw*{>
publicint getEveryPage(){ k WYjqv
return everyPage; ~JY<DW7
} zm rQ7(y
c #+JG
/** =BpX;n<
* @param everyPage kBd #=J
* The everyPage to set. WZaOw w
*/ uUb[Dqn
publicvoid setEveryPage(int everyPage){ v|~ yIywf
this.everyPage = everyPage; SEQ
bw](ss
} b`E'MX_ m
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/** \MM(w&
* @return 9|O#+_=+v
* Returns the hasNextPage. hRZ9[F[[
*/ 5S:#I5Wa
publicboolean getHasNextPage(){ a?%X9 +1A
return hasNextPage; GbG!vo
} HErTFY+vC
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/** %^}3:0G
* @param hasNextPage <N^2|*3
* The hasNextPage to set. ipfiarT~)
*/ \:C@L&3[
publicvoid setHasNextPage(boolean hasNextPage){ 6JBE=9d-Q
this.hasNextPage = hasNextPage; I0oM\~#
} Ro`Hm8o/
nb0V~W
/** qCOe,$\1/
* @return G@b|{!
* Returns the hasPrePage. bWAhK@epI
*/ knZee!FA7
publicboolean getHasPrePage(){ g&;:[&%T]
return hasPrePage; "Q]`~u':
} T:S+Pt~
g!5`R`7
/** x]6OE]]8L
* @param hasPrePage Zuod1;qIh
* The hasPrePage to set. 0 }jB/Z_T
*/ DWZ!B7Ts
publicvoid setHasPrePage(boolean hasPrePage){ q?'*T?|
this.hasPrePage = hasPrePage; !Y/$I?13Z
} !q!.OQ
1t/#ZT!X/
/** ::N'tcZ^2
* @return Returns the totalPage. "#^11 o8
* 4Y8/>uL
*/ A?'Tigi
publicint getTotalPage(){ `yJpDGh
return totalPage; PO5/j
} <m"Zk k
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/** "<x%kD
* @param totalPage ^0ZabR'
* The totalPage to set. r8rU+4\8<
*/ K1a$
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publicvoid setTotalPage(int totalPage){ 2ku\R7
this.totalPage = totalPage; gy/z;fB
} yU3fM?a
uqPagt<
} S1NM9xHJ
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4vcUHa|4
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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 _] veTAV
U=MFNp+
个PageUtil,负责对Page对象进行构造: N=lFf+
java代码: |]sh*<:?,
GZQy~Uk~
z/(^E8F
/*Created on 2005-4-14*/ E9t[Mb %0
package org.flyware.util.page; }N!I|<"/
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import org.apache.commons.logging.Log; x;2tmof=L
import org.apache.commons.logging.LogFactory; i/`N~r
.~qu,q7k~
/** Zoh[tO
* @author Joa k2o98bK&;
* Q.Tn"rE|
*/ I|]~f[xI
publicclass PageUtil { 0\84~t'[
+G*2f
V>
privatestaticfinal Log logger = LogFactory.getLog }stc]L{79
~]P_Yd-|
(PageUtil.class); =B_vQJF2
) *ocX)AE
/** .^0@^%Wi
* Use the origin page to create a new page Ew1>
m'
* @param page <m:8%]%M6
* @param totalRecords zts%oIgV
* @return HM ;9%rtO
*/ Svj%O(
publicstatic Page createPage(Page page, int @DG$
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totalRecords){ aaW(S K
return createPage(page.getEveryPage(), +c!v%uX
Ub!MyXd{q
page.getCurrentPage(), totalRecords); Bfwa1#%?
} ^%tmHDNL.
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/** v:kTZB
* the basic page utils not including exception ["VUSa
"HSAwe`5jU
handler A46z2
* @param everyPage [`^5Zb
* @param currentPage v {E~R
* @param totalRecords uQgv ;jsPz
* @return page Y8YNRyc=
*/ [A99e`
publicstatic Page createPage(int everyPage, int ib8@U}Vn1
7xidBVx
currentPage, int totalRecords){ q_K8vGm4e
everyPage = getEveryPage(everyPage); A]^RV{P
currentPage = getCurrentPage(currentPage); L5 ~wX
int beginIndex = getBeginIndex(everyPage, Kt5;GUV
QyN<o{\FD!
currentPage); <Uf?7
int totalPage = getTotalPage(everyPage, ^"N]i`dIF
kX!TOlk3
totalRecords); 60?/Z2w5
boolean hasNextPage = hasNextPage(currentPage, 2;N)>[3*J
*CG-F=
totalPage); W,'30:#Fr7
boolean hasPrePage = hasPrePage(currentPage); H|&[,&M>
w3oh8NRs_
returnnew Page(hasPrePage, hasNextPage, Ux5pw
everyPage, totalPage, f&x7g. I
currentPage, D/wX
8V$pdz| [
beginIndex); DY| s|:d
} ;^VLx)q
vqDd][ n
privatestaticint getEveryPage(int everyPage){ ";\na!MT
return everyPage == 0 ? 10 : everyPage; 5{?J5
} {z:aZ]QhKc
T;jy2|mLo
privatestaticint getCurrentPage(int currentPage){ <pzCpF<
return currentPage == 0 ? 1 : currentPage; /~RY{ c@#L
} HX\^ecZ#E
iOk^RDG+
privatestaticint getBeginIndex(int everyPage, int >;I$&
b7&5>Q/g
currentPage){ t@dv$W2
"
return(currentPage - 1) * everyPage; p2Yc:9r9+A
} t;g=@o9YA
<49Gsm&0
privatestaticint getTotalPage(int everyPage, int M}Sn$h_
{uVvo=3
totalRecords){ l!z)gto
int totalPage = 0; ~wtl\-cY
iK&s_}i:
if(totalRecords % everyPage == 0) "SGq$3D
totalPage = totalRecords / everyPage; Fo
K!JX*
else X.^S@3[
totalPage = totalRecords / everyPage + 1 ; i> }P V
i}d^a28
return totalPage; a'3|EWS
?
} K1i@.`na/$
V}c3}'_U]
privatestaticboolean hasPrePage(int currentPage){
d~#>.$Uu
return currentPage == 1 ? false : true; $J]VY;C!
} ,ru2C_LQ
PX7@3Y
privatestaticboolean hasNextPage(int currentPage, X)P;UVR0
[N]5)n
int totalPage){ S3Q^K.e?
return currentPage == totalPage || totalPage == `1;m:,9
!kAjne8]d
0 ? false : true; E8$k}I
} j0^%1
SvE3E$*
!$}:4}56F
} <UI^~Azc#
|]s/NNU
9eG{"0)
s.VtmAH
l-?B1gd,l
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。 ]mO$Tg&s~
X9ua&T2(l
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 aNd6#yU$
A5U//y![{
做法如下: S}QvG&c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \53(D7+
Ph{7S43
的信息,和一个结果集List: =v-qao7xCV
java代码: ."HDUo2D7
hn-+]Y:
*2nQZ^c.
/*Created on 2005-6-13*/ "}"hQ.kAz
package com.adt.bo; v2Lx4:dzi
l~_]k
import java.util.List; SQ$|s%)oB
z`)i"O]-K_
import org.flyware.util.page.Page; :
T` Ni
+OEheG8
/** 'MF|(`
* @author Joa ^tp6G
*/ (T&rvE
publicclass Result { hDPZj#(c
>"Tivc5
private Page page;
-L zx3"
tsGt,]O30
private List content; )(^L*
|r|<cc#
/** ,q[aV 6kO
* The default constructor \&[Jtv *
*/ c4\Nuy
public Result(){ abs\Ku9
super(); I%4)%
} nYA@t=t0
vIMLUL0
/** |->P|1
P
* The constructor using fields `Mg&s*
* 8:D|[u;iG
* @param page *?l-:bc]
* @param content $C&y-Hnar
*/ H]zi>;D
public Result(Page page, List content){ 6R`q{}.
this.page = page; DL*/hbG
this.content = content; S9cAw5E(yN
} )iKV"jsC
pv3SAO4
/** nu=yE$BN{
* @return Returns the content. Nj p?/r
*/ O1C|{
M
publicList getContent(){ *#{V^}
return content; \Uz7ar#,
} d3,%Z &
~tw#Q
/** (vO\h8
* @return Returns the page. @^O+ulLJ,]
*/ }KEL{VUX
public Page getPage(){ 2cnyq$4k
return page; j'\!p):H
} f*(W%#*|
Q/u2Q;j>
/** 0`=>/Wr39
* @param content &1ZqC;
* The content to set. /V>q(Q
*/ Xyz w.%4c
public void setContent(List content){ WUN|,P`b
this.content = content; \vKKq/f
} zw2qv'
L
lNd97Z
/** Tgf\f%,h
* @param page `l%)0)T
* The page to set. m|/q
o
*/ X npn{
publicvoid setPage(Page page){ OrG1Mfx&2%
this.page = page; w$`[C+L
} ],?$&
} 3RbPc8($Y
neLQ>WT
L
^KlW"2:
NKy Ksu
&/\Q 6$a
2. 编写业务逻辑接口,并实现它(UserManager, l-mt{2
1xf
Pe#
UserManagerImpl) )XFaVkQ}
java代码: I1Jhvyd?$
6Fe$'TP
`!um)4
/*Created on 2005-7-15*/ i 6DcLE
package com.adt.service; _ Vo35kA
g)L?C'BG
import net.sf.hibernate.HibernateException; ZcQ@%XY3~
*)8!~Hs
import org.flyware.util.page.Page; 4?u<i=i
uOv0ut\\G
import com.adt.bo.Result; :(?F(Q^
Y!1x,"O'H
/** =Z(_lLNmh
* @author Joa H1fKe=$1
*/ cYeC7l"
publicinterface UserManager { N -z
VfFXH,j
public Result listUser(Page page)throws 'v~%rhq3
xG7/[ jG
HibernateException; 5Z<y||=
0W6jF5T
} z, f
==ZL0 ][
^+MG"|)u~
%b1NlzB+
&BZjQK
java代码: UG,<\k&
\@eaSa
/=i+7^
/*Created on 2005-7-15*/ />13?o#
package com.adt.service.impl; 2 {I(A2
yh'P17N|q
import java.util.List; ` 0z8J*T]
d7U%Q8?wUR
import net.sf.hibernate.HibernateException; jqJ't)N
#Aver]eK
import org.flyware.util.page.Page; H[e=^JuD
import org.flyware.util.page.PageUtil; `^G?+p2E
>OotgJnhC
import com.adt.bo.Result; Z'cL"n\9R]
import com.adt.dao.UserDAO; K1oSoD8c
import com.adt.exception.ObjectNotFoundException; Qw@_.I
import com.adt.service.UserManager; `JZ`j7f
6|@\\\l
/** 1:j[p=Q&
* @author Joa VX+:C(m~
*/ b9L"?{
publicclass UserManagerImpl implements UserManager { 9l&4mt;+&<
C?h}n4\B^?
private UserDAO userDAO; aBblP8)8;K
7O]$2
/** 0Q)m>oL.
* @param userDAO The userDAO to set. ?]/"AWUX
*/ H\^zp5/
publicvoid setUserDAO(UserDAO userDAO){ ~/R bYvyA
this.userDAO = userDAO; ;W2Rl%z88
} C_rA'Hy
z:JQ3D7/we
/* (non-Javadoc) i9=*ls^Cx
* @see com.adt.service.UserManager#listUser @\}w8
T:|PSJc0
(org.flyware.util.page.Page) RK\$>KFE
*/ nN*:"F/^
public Result listUser(Page page)throws ?(2^lH~6h
QG8X{'
HibernateException, ObjectNotFoundException { *,y .%`o
int totalRecords = userDAO.getUserCount(); 7@u:F?c
if(totalRecords == 0) {IG5qi?/E)
throw new ObjectNotFoundException 1c19$KHu
abw7{%2
("userNotExist"); d#Xt2
page = PageUtil.createPage(page, totalRecords); (d?sFwOt\
List users = userDAO.getUserByPage(page); |<Rf^"T
returnnew Result(page, users); L; (J6p]h
} T*bBw
T~G~M/
} tEl_a~s*3?
a`E1rK'
=&-+{txs
iRsK;)<
'^ob3N/Y [
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Sft+Gb6
rzO5 3\
询,接下来编写UserDAO的代码: 6JUjT]S%
3. UserDAO 和 UserDAOImpl: W*jwf@
0
java代码: 4lsg%b6_%,
3?Tk[m1b
Dqg~g|(Q<
/*Created on 2005-7-15*/ Jd-u?
package com.adt.dao; V^D!\)#
P; DGs]PF
import java.util.List; 89+Q^79m
eUZvJTE
import org.flyware.util.page.Page; Z+M* z;
{<#~Ya-
import net.sf.hibernate.HibernateException; #57D10j
;'7gg]
/** ? 1
~C`I;
* @author Joa ` Clh;
*/ %DIZgPd\
publicinterface UserDAO extends BaseDAO { jFPD SR5
"inXHxqu/J
publicList getUserByName(String name)throws :+Okv$v4
k:sFI @g
HibernateException; {~a+dEz
k*$[V17
publicint getUserCount()throws HibernateException; qpZR-O
DD^iEhG
publicList getUserByPage(Page page)throws /j(3 ~%]o4
k*"FMJG_
HibernateException; O$,bNu/g
rJws#^]
} ? ht;ZP
P(Wr[lH\y
x2@W,?oPm
QsC6\Gt#
_7P#?:h
java代码: Y2 QX9RN
04}" n
)D>= \Me
/*Created on 2005-7-15*/ *wNO3tP't
package com.adt.dao.impl; Di>B:=
/+g)J0u
import java.util.List; Lcow2 SbH
C'oNGOEd
import org.flyware.util.page.Page; ,3p$Z
o@j)clf
import net.sf.hibernate.HibernateException; +L>?kr[i[
import net.sf.hibernate.Query; p*OpO&oodu
gkRbb
import com.adt.dao.UserDAO; J%SuiT$L&Y
qEy]Rc%
/** oJ`cefcWo
* @author Joa G}ccf%
*/ jc-$l
public class UserDAOImpl extends BaseDAOHibernateImpl 8AQ@?\Rc"2
vAH `tPi>
implements UserDAO { R\^XF8n6/
ml\2%07
/* (non-Javadoc) ,,o5hD0V9
* @see com.adt.dao.UserDAO#getUserByName MbJ|6g99
,bnrVa(I
(java.lang.String) m%[`NP (
*/ XJ{b_h#N
publicList getUserByName(String name)throws o'auCa,N
4 /Q4sE~<
HibernateException { ed:[^#Lj
String querySentence = "FROM user in class nQ}$jOU&
w$%1j+%&
com.adt.po.User WHERE user.name=:name"; Ks_B%d
Query query = getSession().createQuery +204.Yj?D
MF]EX
(querySentence); ^mZ eAW
query.setParameter("name", name); H(,D5y`k1
return query.list(); 8P[aX3T7G
} KVA~|j B
Wv4o:_}
/* (non-Javadoc) f'28s*n
* @see com.adt.dao.UserDAO#getUserCount()
SdM@7%UK
*/ 71(C@/J
publicint getUserCount()throws HibernateException { ro`2IE>
int count = 0; -lDAxp6p
String querySentence = "SELECT count(*) FROM uqFYa bU
bz4TbGg]
user in class com.adt.po.User"; K]s*rPT/,
Query query = getSession().createQuery ,"U_oa3
?D8+wj
(querySentence); 5*P+c(=
count = ((Integer)query.iterate().next yK"T5^o
M#a1ev
()).intValue(); 1xsIM'&
return count; s%xhT
} .|Y&,?k|Y
7w?V0pLwn8
/* (non-Javadoc) N`1W"Rx!
* @see com.adt.dao.UserDAO#getUserByPage yhzZ[vw7k
ey ; 94n:<
(org.flyware.util.page.Page) MeMSF8zSQ
*/ NPY\ >pf
publicList getUserByPage(Page page)throws f&ri=VJY\T
&w"1VOV<
HibernateException { lwj,8
String querySentence = "FROM user in class 0<'Q;'2* L
/ij)[WK@
com.adt.po.User"; ;.EW7`)Z
Query query = getSession().createQuery 6X`i*T$.
2T >K!jS
(querySentence); ~+OAAkJ9
query.setFirstResult(page.getBeginIndex()) DLBHZ?+!
.setMaxResults(page.getEveryPage()); >uR0Xs;V
return query.list(); b`yb{&
,?
} T2/lvvG
+2?=W1`
} waRK$/b
(
4_&+]S
k?7V#QW(
o{r<=X ysM
RW I7eC
至此,一个完整的分页程序完成。前台的只需要调用 #ssSs]zl
jS<(Oo
userManager.listUser(page)即可得到一个Page对象和结果集对象 %f'mW2
(]gd$BgD
的综合体,而传入的参数page对象则可以由前台传入,如果用 :+*q,lX8
1
|T{RY5
webwork,甚至可以直接在配置文件中指定。 jPc"qER!
{Z!x]}{M
下面给出一个webwork调用示例: pS6p}S=1]
java代码: TpIx!R9
e/s8?l
^]{m*bEkR
/*Created on 2005-6-17*/ 3 jR I@
package com.adt.action.user; K0xka[x=(
YggeKN
import java.util.List; &'KJh+jJ
4M,Q{G|e
import org.apache.commons.logging.Log; Z(c3GmY
import org.apache.commons.logging.LogFactory; -{O>'9'1A
import org.flyware.util.page.Page; MFzJ 8^.1R
b;k3B7<
import com.adt.bo.Result; R.'-jvO
import com.adt.service.UserService; h}$g}f%$+
import com.opensymphony.xwork.Action; lNRGlTD%
SR8)4:aKW
/** Q!*}^W
* @author Joa |S0nR<x-M
*/ 1~aP)q
publicclass ListUser implementsAction{ o4PJ9x5R!
~4^~w#R
privatestaticfinal Log logger = LogFactory.getLog %pG^8Q()
cM 5V%w
(ListUser.class); OAw- -rl
]o+5$L,5b
private UserService userService; G~mLc
8Z[YcLy"({
private Page page; `WRM7
$s.:H4:I
privateList users; j0`)m R}
K6d2}!5
/* tPqWe2
* (non-Javadoc) UYw=i4J'
* <reALC
* @see com.opensymphony.xwork.Action#execute() I 6-.;)McO
*/ v1O 1-aM
publicString execute()throwsException{ :}*
Result result = userService.listUser(page); sFbN)Cx
page = result.getPage(); <N'v-9=2jl
users = result.getContent(); V]Z!x.x"=y
return SUCCESS; D`NPU
} A29R5
dtx3;d<NsJ
/** X%rsa7H3J
* @return Returns the page. euiP<[|h=
*/ !fmbm4!a
public Page getPage(){ j/p1/sJ[y
return page; AC&)FY
} m xEniy
nr]:Y3KyxX
/** fvBL? x
* @return Returns the users. f"RS,]
*/ 4..M *U
publicList getUsers(){ [JVEKc ym
return users; E! GH$%:;
} J~.`
v8l3{qq
/** =JNCQu
* @param page Us2IeR
* The page to set. >r\q6f#J4
*/ `F`{s`E)
publicvoid setPage(Page page){ 8}K^o>J&K
this.page = page; CuT50N;tk
} 38#Zlcf
8_Nyy/K#F
/** !rsGCw!Pg
* @param users \k
6'[ln
* The users to set. H):(8/>(
*/ %WF]mF T_
publicvoid setUsers(List users){ IhjZ{oV/@
this.users = users; XY^]nm-{I
}
35%\"Y?
|i\%>Y,
/** +l hJ8&
* @param userService lG5KZ[/Or
* The userService to set. '\M]$`Et
*/ 5=_bK^Am
publicvoid setUserService(UserService userService){ Tx>V$+al
this.userService = userService; 8I[=iU7]l
} Ef$a&*)PH
} FDal;T
Ggk#>O G
`0, G'F
V}X>~ '%
H<9_BA?
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, H~
E<ek'~
%<0'xJ%%Q
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 [\3W_jR
J9-n3o
么只需要: X;]Ijha<*
java代码: \q@Co42n\
gA}?X
zfw=U
\
<?xml version="1.0"?> qV0GpVJZU?
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork }qT{" *SC
[vqf hpz
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;ObrBN,Fu
F0kdwN4;
1.0.dtd"> k+BY 3a
]P/i}R:
<xwork> #>M^BOR8
xzHb+1+p
<package name="user" extends="webwork- [/o BjiBA
8]mRX~
interceptors"> B$M4f7
6UI6E)g
<!-- The default interceptor stack name "5204I
-tIye{
--> iPdS>ee
<default-interceptor-ref lAR1gHhJ
Kr?<7vMT5
name="myDefaultWebStack"/> 6 2#@Y-5
L*OG2liJ
<action name="listUser" bFhZSk)
$zM \Jd
class="com.adt.action.user.ListUser"> (&SPMhs_|(
<param RzU9]e
:{
iK 5
name="page.everyPage">10</param> zZ,"HY=jN
<result .k$Yleg
6l:uQz9
name="success">/user/user_list.jsp</result> Dn)B19b
</action> B@v
(ZY
l9e=dV:pH
</package> 9k\M<jA
*cZ7?
</xwork> M@JW/~p'
nDcH;_<;9a
:k-@w5(
*R}p9;dpO
5=\^DeM@
H
KZO[>qC"R
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 eLLOE)x
;l^'g}dQ^
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。 4V c``Um
O`$\Plt|v
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 +koW3>
B}nT>Ub
&dPUd~&EL
Yxy!&hPLv:
9oIfSr,y
我写的一个用于分页的类,用了泛型了,hoho Sk:x.oOZ
5g.w"0MkY
java代码: qHgzgS7a
m#ig.z|A
Vju/+
package com.intokr.util; e,Z[Nox
zJ$U5r/u
import java.util.List; <,Pl31g^
4]FS
jVO
/** !Na@T]J
* 用于分页的类<br> 6v74mIRn'?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2I|lY>Z
* 97 ,Y q3
* @version 0.01 nBLb1T
* @author cheng =dwy 4
*/ "&{.g1i9
public class Paginator<E> { 6J_$dzw
privateint count = 0; // 总记录数 I2krxLPd
privateint p = 1; // 页编号 0dQ\Y]b
privateint num = 20; // 每页的记录数 Z?d][zGw
privateList<E> results = null; // 结果 c[T@lz(!
cltx(C>
/** qA[cF$CIl)
* 结果总数 <2fy(9y
*/ =**Q\Sl
publicint getCount(){ %%#bTyF
return count; <Ql2+ev6
} +z0s)HU>j
qu^~K.I"
publicvoid setCount(int count){ 0|i|z!N>
this.count = count; _T7XCXEk
} }346uF7C
GHo
mk##0E
/** u/NcX
* 本结果所在的页码,从1开始 B~M6l7^?
* G*,7pc
* @return Returns the pageNo. jtq^((Ux
*/ tv Zq):c
publicint getP(){ lon9oraF'
return p; ;Wa&Dg/5`
} Jl6lZd(Np
dt>9mF q
/** \.+:yV<$
* if(p<=0) p=1 TA8
* OOXP1L
* @param p -%Ce
*/ =diGuIB
publicvoid setP(int p){ rg=Ym.
if(p <= 0) K`j:F>b
p = 1; ,b5vnW\
this.p = p; 6'x3g2C/
} g3yZi7b5FU
Gm3`/!r
/** B#}EYY
* 每页记录数量 sl(go^
*/ yhI;FNSf
publicint getNum(){ ]rNxvFN*j
return num; lgD%
} ks
%arm&
r:Q=6j,
/** 3.g 4X?=zd
* if(num<1) num=1 $dWYu"2CD
*/ ~;YkR'q0_
publicvoid setNum(int num){ Pp_? z0M
if(num < 1) Ra6 }<o
num = 1; rZ)7(0BBs
this.num = num; )D)4=LJ
} {t.S_|IE
3xKgj5M
/** [0]J
2
* 获得总页数 'm"Ez'sS
*/ a#x@e?GvI
publicint getPageNum(){ $ER9u2
return(count - 1) / num + 1; F- M)6&T
} 'H4?V
B2KBJ4rI[1
/** FFe{=H,=
* 获得本页的开始编号,为 (p-1)*num+1 (_+ux1h6^
*/ R=$}uDFmW
publicint getStart(){ e.#,9
return(p - 1) * num + 1; HD1/1?y!@q
} ?Iij[CbU
ts("(zI1E
/** rz2,42H]
* @return Returns the results. ue4{h
*/ (
z F_<
publicList<E> getResults(){ %`\Qtsape
return results; yF_/.m I
} M'oZK
=vriraV"
public void setResults(List<E> results){ (H:A|Lw
this.results = results; ]2ycJ >w
} lz1cLl
m
hd[t&?{=
public String toString(){ J4z&J SY
StringBuilder buff = new StringBuilder ,^ dpn
Z!jJ93A"
(); _JA)""l%
buff.append("{"); <X5ge>.
buff.append("count:").append(count); "(kiMog-
buff.append(",p:").append(p); g:U
-kK!i
buff.append(",nump:").append(num); a40>_;}:x
buff.append(",results:").append 4cJ/XgX
(v:8p!QN
(results); Y%@;\
buff.append("}"); ~ahu{A4Bw
return buff.toString(); l|vT[X/g
} N=~DSsw
">S1,rhgS
} w\V<6_[vv.
7s2*VKr
0tPwhJ