Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 V[^+lR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?O.'_YS
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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 [{-5
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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 byN4?3F
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分页支持类: aFd87'^
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java代码: 6e4A|<
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package com.javaeye.common.util; U*cWNn:."
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import java.util.List; J"?jaa2~
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publicclass PaginationSupport { V\P
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;
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publicfinalstaticint PAGESIZE = 30; }c,:uN
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privateint pageSize = PAGESIZE; :IRQouTf:,
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privateList items; ]>oI3&6s
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privateint totalCount; G4{TJ,~
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privateint[] indexes = newint[0]; PmlQW!gfBi
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privateint startIndex = 0; B/gI~e0
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public PaginationSupport(List items, int a8cX{6
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totalCount){ Z/+H
setPageSize(PAGESIZE); 22gh,e2o
setTotalCount(totalCount); 6bd{3@
setItems(items); N7#,x9+E
setStartIndex(0); m4 :"c"
} IvJ5J&!
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public PaginationSupport(List items, int ~09k IO)
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totalCount, int startIndex){ g<s;uRA4O9
setPageSize(PAGESIZE); TykY> cl
setTotalCount(totalCount); KYC<*1k
setItems(items); U{PFeR,Uk
setStartIndex(startIndex); 9ve)+Lk
} R/ 3#(5
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public PaginationSupport(List items, int bw*D!mm,
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totalCount, int pageSize, int startIndex){ gM_MK8py
setPageSize(pageSize); :8l#jU`y
setTotalCount(totalCount); ]:Sb#=,!&!
setItems(items); g]m}@b6(h
setStartIndex(startIndex); Mk|*=#e;
} ?7Skk
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publicList getItems(){ I^!c1S
return items; ,N@N4<C]
} BBHoD:l
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publicvoid setItems(List items){ G ;
this.items = items; o{xA{ @<
} FcmL4^s.`
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publicint getPageSize(){ "xp>Vj
return pageSize; "= >8UR
} _2rxDd1#.
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publicvoid setPageSize(int pageSize){ #r;uM+
this.pageSize = pageSize; Rkh
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} $*vj7V_
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publicint getTotalCount(){ 0&2eiMKG?n
return totalCount; Q)ZbnR2Z8
} %lqrq<Xn
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publicvoid setTotalCount(int totalCount){ C:{&cIFrPe
if(totalCount > 0){ eZ;DNZK av
this.totalCount = totalCount; W=zp:6Z~
int count = totalCount / dY'>'1>P
9
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pageSize; S'(Hl}h!.
if(totalCount % pageSize > 0) @+(a{%~7y
count++; :AM_C^j~
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indexes = newint[count]; $S2kc$'F
for(int i = 0; i < count; i++){ *Fz#x{zt
indexes = pageSize * Ufv0Xj
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i; u%rB]a$/
} 7oFA5T _
}else{ 7,,#f&jP
this.totalCount = 0; ;%Rp=&J
} [eZ'h8
} q\T}jF\t
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publicint[] getIndexes(){ D[bPm:\0M
return indexes; iYb{qv_4
} ?PDrj/: *
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publicvoid setIndexes(int[] indexes){ "MU)8$d
this.indexes = indexes; .8/W_iC92
} /<it2=
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publicint getStartIndex(){ "7_qB8\
return startIndex; %a$Fsn
} 'QxPQcU
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publicvoid setStartIndex(int startIndex){ .9KW|(uW
if(totalCount <= 0) Nj|~3
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this.startIndex = 0; ]_&pIBp
elseif(startIndex >= totalCount) tqT-9sEXX.
this.startIndex = indexes bZi;jl
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[indexes.length - 1]; FaA7m
elseif(startIndex < 0) GN
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this.startIndex = 0; qwDoYyyu
else{ ]WZi +
this.startIndex = indexes .}DL%E`n
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[startIndex / pageSize]; Jej-b<HmQ
} q<!KtI4
} 2-.%WhE/
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publicint getNextIndex(){ wVY;)1?
int nextIndex = getStartIndex() + "U%jG`q
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pageSize; ~n`G>Oe3
if(nextIndex >= totalCount) \|q.M0
return getStartIndex(); W5a>6u=g,
else TM?7F2
return nextIndex; i"U<=~
} XIJ{qrDr
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publicint getPreviousIndex(){ `8N],X
int previousIndex = getStartIndex() - *'hvYl/?>
nO7#m~
pageSize; G?QU|<mj<
if(previousIndex < 0) VKXZA2<?'
return0; DsH`I%w{
else fE&wtw{gi
return previousIndex; 8GFA}_(^R
} ZeYkZzN
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} }^ G&n';J
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抽象业务类
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java代码: 'P5|[du+
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/** ^7&0Pm
* Created on 2005-7-12 M/^kita
*/ 2gb MUdpp
package com.javaeye.common.business; ~TEKxgU
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import java.io.Serializable; /]*#+;;%
import java.util.List; A`qb5LLJ)
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import org.hibernate.Criteria; $>mTPNF
import org.hibernate.HibernateException; 8GD!]t#
import org.hibernate.Session; ]VS$ ?wD
import org.hibernate.criterion.DetachedCriteria; =\l7k<
import org.hibernate.criterion.Projections; ;
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import Mb0cdK?hA
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org.springframework.orm.hibernate3.HibernateCallback; MOEB{~v`;
import 3U73_=>=&
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org.springframework.orm.hibernate3.support.HibernateDaoS =#c?g Wb56
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upport; WxFrqUz
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import com.javaeye.common.util.PaginationSupport; r`T(xJ!)
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public abstract class AbstractManager extends ,Cckp! 6
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HibernateDaoSupport { -O=a"G=
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privateboolean cacheQueries = false; h.W;Dmf6]
);.q:"
privateString queryCacheRegion; 'ehJr/0&g
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publicvoid setCacheQueries(boolean t"@:a
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cacheQueries){ r&|-6OQZZ
this.cacheQueries = cacheQueries; VIxt;yE
} cn4CK.?
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publicvoid setQueryCacheRegion(String 6T_Mk0Sf+
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queryCacheRegion){ F"-w
this.queryCacheRegion = @9QtK69
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queryCacheRegion; 6*,8 H&
} 3T3p[q4
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publicvoid save(finalObject entity){ ( |1 $zF+
getHibernateTemplate().save(entity); 5M{DJ/q
} fr0iEO_
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publicvoid persist(finalObject entity){ *eO@<j?
getHibernateTemplate().save(entity); M_2[Wypw
} e,}]K'!t
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publicvoid update(finalObject entity){ 1;l&ck-Gg/
getHibernateTemplate().update(entity); %8T:r S
} !t["pr\
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publicvoid delete(finalObject entity){ O]n"aAu@
getHibernateTemplate().delete(entity); qYW{$K
} }V3p <
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publicObject load(finalClass entity, *Bt`6u.>e,
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finalSerializable id){ +_?;%PKkuF
return getHibernateTemplate().load gno V>ON0
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(entity, id); +OF(CcA^
} zJ#e3o .
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publicObject get(finalClass entity, EO,;^RtB
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finalSerializable id){ 6$>m s6g%
return getHibernateTemplate().get N1KYV&'o
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(entity, id); <=V2~
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} 2k[i7Rl \c
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publicList findAll(finalClass entity){ *_$%Tv.]
return getHibernateTemplate().find("from w.cQ|_
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" + entity.getName()); :rb<mg[
} k3[
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publicList findByNamedQuery(finalString XQ<2(}]4
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namedQuery){ xyx.1o
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return getHibernateTemplate | zj$p~
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().findByNamedQuery(namedQuery); I<.3"F1}
} F]W'spF,
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publicList findByNamedQuery(finalString query, /40Z-'Bl=(
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finalObject parameter){ pN&Dpz^
return getHibernateTemplate xkOyj`IS
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().findByNamedQuery(query, parameter); zp4Jd"XBX
} {t[j>_MYw
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publicList findByNamedQuery(finalString query, @4h .?
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finalObject[] parameters){ `6!l!8
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return getHibernateTemplate ReP7c3D>p
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().findByNamedQuery(query, parameters); c\.4I4uy
} [dsH0 D&T
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publicList find(finalString query){ -zHJ#
return getHibernateTemplate().find PF@<>NO+W
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(query); l{aXX[E&1
} m$A|Sx&sG$
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publicList find(finalString query, finalObject 8;.WX
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parameter){ zp"sM
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return getHibernateTemplate().find kwK<?\D
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(query, parameter); Z KnEg2a
} cy?u
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public PaginationSupport findPageByCriteria M'HmVg4'
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(final DetachedCriteria detachedCriteria){ _i:yI-jA
return findPageByCriteria O~-#>a
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8@Xq ,J
} ve=oH;zf
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public PaginationSupport findPageByCriteria N(]6pG=
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(final DetachedCriteria detachedCriteria, finalint I8`@Srw8
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startIndex){ P$Xig
return findPageByCriteria k%/Z.4vQG
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(detachedCriteria, PaginationSupport.PAGESIZE, c&AA< 6pkv
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startIndex); )fpZrpLXE
} hPx=3L$
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public PaginationSupport findPageByCriteria sk$MJSE
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(final DetachedCriteria detachedCriteria, finalint WWc{]R^D
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pageSize, F%lP<4Vx
finalint startIndex){ %IW=[D6Tg
return(PaginationSupport) &voyEvX/S
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getHibernateTemplate().execute(new HibernateCallback(){ ; @-7'%(C
publicObject doInHibernate 2ME3= C
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(Session session)throws HibernateException { d>)*!l2,C
Criteria criteria = 9EK5#_L[=
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detachedCriteria.getExecutableCriteria(session); l^%Ez?-:s
int totalCount = /'u-Fr(Q+
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((Integer) criteria.setProjection(Projections.rowCount SI*O#K=w
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()).uniqueResult()).intValue(); {b"V7vn,
criteria.setProjection C\j|+s
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(null); ^|Of
List items = |(*ReQ?=
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criteria.setFirstResult(startIndex).setMaxResults - ~T LI&[
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(pageSize).list(); g599Lc&
PaginationSupport ps = vkOCyi?c
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new PaginationSupport(items, totalCount, pageSize, H@qA X
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startIndex); t`o-HWfS.
return ps; B5~S&HQ?B6
} 0ym>Hbax)
}, true); B4r4PSB>!
} .v9 #|d d+
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public List findAllByCriteria(final MVs@~=
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DetachedCriteria detachedCriteria){ PzWhB* iBR
return(List) getHibernateTemplate cclx$)X1X
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().execute(new HibernateCallback(){ %]h5\%@w
publicObject doInHibernate !<Ma9%uC{
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(Session session)throws HibernateException { uwXquOw
Criteria criteria = U
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detachedCriteria.getExecutableCriteria(session); A7 qyv0F
return criteria.list(); ']WS@MbJ
} uK6R+a
}, true); 7](,/MeGG
} B+#!%J_
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public int getCountByCriteria(final KbQ UA$gL=
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DetachedCriteria detachedCriteria){ C}<j8a?
Integer count = (Integer) g'ha7~w(p
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getHibernateTemplate().execute(new HibernateCallback(){ PTWP7A[
publicObject doInHibernate WUm83"
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(Session session)throws HibernateException { /bv1R5
Criteria criteria = Q0K2md_%x
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detachedCriteria.getExecutableCriteria(session); \
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return RZ-=UIf
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criteria.setProjection(Projections.rowCount l=ehoyER
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()).uniqueResult();
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} 18f!k
}, true); D1rXTI$$
return count.intValue(); ;gLHSHEA
} ecDni>W
} V9&7K65-1
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用户在web层构造查询条件detachedCriteria,和可选的 (KtuikJ32^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 n}/?nP\%
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PaginationSupport的实例ps。 'APtY;x^{
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ps.getItems()得到已分页好的结果集 :>4pH
ps.getIndexes()得到分页索引的数组 ]CHO5'%,$
ps.getTotalCount()得到总结果数 1BK!<}yI{
ps.getStartIndex()当前分页索引 GOrDDp
ps.getNextIndex()下一页索引 tj$&89
ps.getPreviousIndex()上一页索引 -< D7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HY-7{irR~
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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 H@ Yj
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一下代码重构了。 [rk*4b ^s
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我把原本我的做法也提供出来供大家讨论吧: p+M#hF5o
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首先,为了实现分页查询,我封装了一个Page类: cjK\(b3
java代码: [PG#5.jwQ
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/*Created on 2005-4-14*/ dpG l
package org.flyware.util.page; -KV)1kET
sNB*S{
/** vd<r}3i*
* @author Joa SB~HHx09
* )(bAi
*/ o]T-7Gs4p
publicclass Page { h0**[LDH
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/** imply if the page has previous page */ <"/b 5kc
privateboolean hasPrePage; oKyl2jg+,
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/** imply if the page has next page */ CCoT
privateboolean hasNextPage; HGycF|]2
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/** the number of every page */ rtM29~c>@
privateint everyPage; )M3}6^s]
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/** the total page number */ B
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privateint totalPage; T{WJf-pI
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/** the number of current page */ WAq)1gwN
privateint currentPage; !s^[|2D_U
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/** the begin index of the records by the current -Cn x!g}
up _Qv#`Q
query */ +"} #4
privateint beginIndex; ^*?mb)
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/** The default constructor */ \B/!}Tn;
public Page(){ UP<B>Y1a
\7V[G6'{
} Sb QM!Q
RnV#[bM{
/** construct the page by everyPage MZIZ"b
* @param everyPage #(pY~\
* */ K92nh/}y
public Page(int everyPage){ 6(pa2
this.everyPage = everyPage; 0*J},#ba$
} 1&Z#$iD
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/** The whole constructor */ fEJF3<UF&
public Page(boolean hasPrePage, boolean hasNextPage, y':JUwUN
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int everyPage, int totalPage, #'y4UN
int currentPage, int beginIndex){ JnE\z*NB
this.hasPrePage = hasPrePage; }[;{@Zn
this.hasNextPage = hasNextPage; R1cOUV,y[/
this.everyPage = everyPage; )L+>^cJI<
this.totalPage = totalPage; J;DTh ]z?:
this.currentPage = currentPage; bVxbQ$
this.beginIndex = beginIndex; !kW~s_gUb*
} ;$.^
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/** N({0" 7
* @return BbIg]E/G
* Returns the beginIndex. `;
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*/ "?AJ(>wP
publicint getBeginIndex(){ fphi['X
return beginIndex; /OD@Xl];K
} MV.&GUez{
SD_P=?
/** 4`Ib wg6"B
* @param beginIndex V=d~}PJ>
* The beginIndex to set. ~'#yH#o
*/ M
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publicvoid setBeginIndex(int beginIndex){ |=u
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this.beginIndex = beginIndex; 4e20\q_{
} 50`=[l`V
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/** Um~DA
* @return % `\}#
* Returns the currentPage. pqF!1
*/ P=<>H9p:o
publicint getCurrentPage(){ c BcZ@e;
return currentPage; 'O^<i`8U]
} *";O_ :C!
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/** ThiM6Hb
* @param currentPage U[O7}Nsb"
* The currentPage to set. o_C]O"
*/ (z.4er}o
publicvoid setCurrentPage(int currentPage){ eWGaGRem
this.currentPage = currentPage; ET0^_yk
} AfT;IG%Gt
) :VF^"
/** Y52TC@'
* @return {
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* Returns the everyPage. ZH)thd9^b
*/ Ba}<X;B }
publicint getEveryPage(){ gP2<L5&Z,
return everyPage; d3;Sy`.
} -|2k$W
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/** kInU,/R*
* @param everyPage kXN8hU}iq
* The everyPage to set. R ~? 9+
*/ yvCX
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publicvoid setEveryPage(int everyPage){ \AOHZ r
this.everyPage = everyPage; \R[f< K%
} ,1
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/** LEd@""h
* @return _ SJFuv/
* Returns the hasNextPage. G-[.BWQ
*/ Ex+E66bE
publicboolean getHasNextPage(){ 7-Mm+4O9
return hasNextPage; }B`T%(11=
} !B/5@P
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/** kYZj^tR
* @param hasNextPage HhB&vi
* The hasNextPage to set. "IJ 9vXI
*/ tjJi|
publicvoid setHasNextPage(boolean hasNextPage){ a v"dJm
this.hasNextPage = hasNextPage; lho0Xy
gn
} FT6~\9m(
}u+cS[#-
/** T4Io+b8$
* @return $u cmE
* Returns the hasPrePage. 7v
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*/ si1Szmx,
publicboolean getHasPrePage(){ PouWRGS_
return hasPrePage; 2gJkpf9JN
} (mgv:<c;BA
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/** XP(fWRT1
* @param hasPrePage \:jJ{bl^A
* The hasPrePage to set. `zOn(6B;U
*/ :Izdj*HL;A
publicvoid setHasPrePage(boolean hasPrePage){ GhR%f xe
this.hasPrePage = hasPrePage; AP9>_0=
} 1T
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/** 'MQJt2QU9{
* @return Returns the totalPage. *6wt+twH
* 5Ve
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*/ \# _w=gs<i
publicint getTotalPage(){ r*g<A2g%
return totalPage; |$D`*
} O4oI&i 7
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/** 4Un%p7Y~
* @param totalPage ;3&HZq6Z (
* The totalPage to set. Gj&`+!\
*/ S\0?~l"}
publicvoid setTotalPage(int totalPage){ :+Tvq,/"
this.totalPage = totalPage;
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} \<%?=C'w~
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} P;K <P
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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 zRFvWOxC\
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个PageUtil,负责对Page对象进行构造: CD pLV:
java代码:
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/*Created on 2005-4-14*/ Qq<+QL |
package org.flyware.util.page; eT@,QA(3
k? !'OHmBL
import org.apache.commons.logging.Log; s!?T$@a=
import org.apache.commons.logging.LogFactory; lr9s`>9
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/** PvW~EJ
* @author Joa cm`x;[e6l
* F!cRx%R
*/ Z`x*Igf8
publicclass PageUtil { :|N(:W>=$Y
%Wa. 2s
privatestaticfinal Log logger = LogFactory.getLog _$m1?DZ
=-;J2Qlg6
(PageUtil.class); L+Q.y~
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/** c52S2f7
* Use the origin page to create a new page :tT6V(-W
* @param page 3>%:%bP
* @param totalRecords mH9_HK.C
* @return A;7At!kK
*/ tjbI*Pw7(
publicstatic Page createPage(Page page, int Bn5$TiTcl
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totalRecords){ ,rWej;CzN
return createPage(page.getEveryPage(), 4_d'Uh&]
6.k>J{GG
page.getCurrentPage(), totalRecords); DwIX\9
} KVp3pUO
+t*Ks_V,*
/** G'(8/os{
* the basic page utils not including exception HBcL1wfS
~ ":}Rs
handler %Iv*u sXP
* @param everyPage ,o sM|!,
* @param currentPage DgKe!w$
* @param totalRecords 6Jd.Eg ~A7
* @return page 17+2`@vJgM
*/ \pVWYx
publicstatic Page createPage(int everyPage, int yc.9CTxx
W5R /
currentPage, int totalRecords){ a
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everyPage = getEveryPage(everyPage); L[O.]2
currentPage = getCurrentPage(currentPage); ^'Qe.DW[
int beginIndex = getBeginIndex(everyPage, v_I)eac z
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currentPage); S(Q=2Y
int totalPage = getTotalPage(everyPage, Qb?eA
st wxF?\NS
totalRecords); 1hW"#>f7
boolean hasNextPage = hasNextPage(currentPage, M7\yEi"*
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totalPage); l G $s(
boolean hasPrePage = hasPrePage(currentPage); #SqU>R
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returnnew Page(hasPrePage, hasNextPage, _
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everyPage, totalPage, ^e(*{K;8
currentPage, 5?XIp6%x
o>Q=V0?
beginIndex); OtZc;c
} i?B(I4a!G
r"&VG2c0K
privatestaticint getEveryPage(int everyPage){ % jSB9
return everyPage == 0 ? 10 : everyPage; UzT"Rb:e
} eKW^\
"RLv{D<)J,
privatestaticint getCurrentPage(int currentPage){ Yqb3g(0
return currentPage == 0 ? 1 : currentPage; rLp (}^
} ##BfI`FJ
>wf.C%
privatestaticint getBeginIndex(int everyPage, int k@>y<A{;D
@w73U;9\
currentPage){ G1G*TSf
return(currentPage - 1) * everyPage; FS7@6I2Ts
} oP_}C[
1)hO!%
privatestaticint getTotalPage(int everyPage, int tPaNhm[-q7
=_Ip0FfK!
totalRecords){ ayrCLv
int totalPage = 0; ;%!]C0?
$HP<C>^Z8
if(totalRecords % everyPage == 0) VRD:PVz
totalPage = totalRecords / everyPage; ]La~Bh6;m
else '|@?R |i0
totalPage = totalRecords / everyPage + 1 ; $$e"[g
lky5%H
return totalPage; ]4eIhj?
} Eh&-b6:
~zhP[qA})
privatestaticboolean hasPrePage(int currentPage){ 5aJd:36I
return currentPage == 1 ? false : true; % 9} ?*U
} AI#.G7'O
"I0F"nQ
privatestaticboolean hasNextPage(int currentPage, XU|>SOR@z
FgnPh%[u
int totalPage){ "-R19SpJKh
return currentPage == totalPage || totalPage == 0$=w8tP)
4~~G
i`XE
0 ? false : true; 1Uk Gjw1J
} D|D)782
>b2wFo/em
S(PU"}vZy
} 'w?}~D.y
,*CPG$L
<5o
oML]nP
F}c}I8Ao
/q5!p0fH*
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。 ;}}k*<
Z
GS+Z(,J>=
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 74fE%;F
QE+HL8c^s
做法如下: L~{3W
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 W]I+Rlv)U
Wgb L9'}B
的信息,和一个结果集List: @G^m+-
java代码: Hv-f :P O
GD0Q`gWNe
OE=.@Ry"
/*Created on 2005-6-13*/ hw2Sb,bY
package com.adt.bo; Zmz $
hr
:%>TM/E N
import java.util.List; d8.A8<wUr
+*Zjo&pc
import org.flyware.util.page.Page; 7f>~P_
ne
8rF.D
/**
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* @author Joa T&^b~T(y
*/ ).IK[5Q`
publicclass Result { T\w{&3ONm
8 `}I]
private Page page; tL]T_]z
P(aN6)D
private List content; >E9 k5
YK>?;U+|
/** }///k]_Sh
* The default constructor ){4 !
*/ zKfY0A R
public Result(){ RC!9@H5S#
super(); EIF"{,m
} 6cXZ3;a
s9,Z}]Th
/** ',]^Qu`a
* The constructor using fields p4vX3?&1W
* <Yn-sH
* @param page GDYFhH7H
* @param content 5xhYOwQBo
*/ R5=M{
public Result(Page page, List content){ i2E@5 v=|Y
this.page = page; v(;n|=O
this.content = content; `]F#j ]"
} Y2}m/7aF
7 )*q@
/** #|K5ma
* @return Returns the content. |O{kv}YZ
*/ xE-
_Fv9
publicList getContent(){ '?1g_C QsS
return content; $0*D7P^8
} <Aqo[']
e \.
/** B/I1<%Yk
* @return Returns the page. ZMGC@4^F
*/ gWfMUl
public Page getPage(){ pkc*toW
return page; g`dAj4B
} W1ql[DqE{
bMGXx>x
/** yH0vESgv
* @param content S]?I7_
* The content to set. gwDVWhq
*/ jD?*sd
public void setContent(List content){ dH)\zCt
this.content = content; |LirjC4
} <=%=,Yk
?%*p!m
/** :kvQ3E0
* @param page (w` j?c1
* The page to set. [I,s: mn
*/ DDe`Lb%%
publicvoid setPage(Page page){ _8e0vi!~2
this.page = page; GYtp%<<9;
} ]QJ7q}
} 84/#,X!=s
l:*.0Tj
-'T^gEd)c
C?g<P0h
>dnDN3x
2. 编写业务逻辑接口,并实现它(UserManager, uOPLJ?%
8aTo
TA7JA
UserManagerImpl) \f'=
java代码: kV4,45r
_|7bpt9
mXI'=Vo!S
/*Created on 2005-7-15*/ 6L3i
package com.adt.service; NXOcsdcZu
>aT~G!y
import net.sf.hibernate.HibernateException; JZ/T:Hsh4
*fI\|%K
import org.flyware.util.page.Page; n(
zzH
t@jke
import com.adt.bo.Result; q^6l`JJ
8|tnhA]~
/** uP.dCs9-
* @author Joa bycnh
*/ Zou;o9Ww
publicinterface UserManager { a~Yq0 d?`D
%v[KLMo'(
public Result listUser(Page page)throws ucFfxar"
=lL)g"xX
HibernateException; Tr,
zV
3[<D"0#},
}
pzb`M'Z?C
F!P,%JmI<
*hh iIiog+
ne%(`XY{Q]
0F 6~S
java代码: %rO)w?
rN'}IS@5
\{={{O
/*Created on 2005-7-15*/ fa!8+kfi
package com.adt.service.impl; >^D5D%"
FY
pspv?4
import java.util.List; V^_U=Ed@M
#lF 2qw
import net.sf.hibernate.HibernateException; G4uA&"OE
,;n[_f
import org.flyware.util.page.Page; lD$\t/8B
import org.flyware.util.page.PageUtil; 8d(l)[GZt
Dlz1"|SF
import com.adt.bo.Result; }j{Z
&(K
import com.adt.dao.UserDAO; gUme({h&|
import com.adt.exception.ObjectNotFoundException; oiQ:&$y
import com.adt.service.UserManager; sU/vXweky"
R#!Urhh
/** 7,Y+FZ
* @author Joa 7V&ly{</
*/ luJNdA:t&
publicclass UserManagerImpl implements UserManager { De<i
8/^=
GjbOc
private UserDAO userDAO; Kf`/ Gc!
[Xww`OUsh
/** L$ZsNs+
* @param userDAO The userDAO to set. PoD/i@
*/ &;U
F,
publicvoid setUserDAO(UserDAO userDAO){ p,14'HS%@
this.userDAO = userDAO; I7W?}bR*6
} v.c.5@%%o
*S'?u_Y7
/* (non-Javadoc) h$p}/A
* @see com.adt.service.UserManager#listUser oz7=1;r
Qjmo{'d
(org.flyware.util.page.Page) .x1.` Y
*/ tg7QX/KX
public Result listUser(Page page)throws 9/{ 8Y&
q siV
HibernateException, ObjectNotFoundException { z&z5EtFUTh
int totalRecords = userDAO.getUserCount(); ,r;E[k@
if(totalRecords == 0)
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throw new ObjectNotFoundException K4b2)8
g`4WisL1n
("userNotExist"); d w'P =8d
page = PageUtil.createPage(page, totalRecords); \_7'f
List users = userDAO.getUserByPage(page); '
?a d
returnnew Result(page, users); \vE-;,
} v!AfIcEV
Yn>FSq^Wp-
} u]P9ip"Z
$?On,U
y:k7eE"
\W|ymV_Ki
\/9 O5`u*V
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .Dy2O*`
o1H6E1$=
询,接下来编写UserDAO的代码: B/B`=%~5_^
3. UserDAO 和 UserDAOImpl: H%ScrJ#V
java代码: c_Iq!MH
&:~9'-O
B^.:dn
/*Created on 2005-7-15*/ .g_^! t
package com.adt.dao; 'l3 DP
#
S0N`V
import java.util.List; pL: r\Y:R
<3x:nH @
import org.flyware.util.page.Page; a..LbQQ
9{%/I
import net.sf.hibernate.HibernateException; [-^xw1:
=-avzuy#
/** WfQZ7e
* @author Joa oo1h"[
*/ QN#tj$x
publicinterface UserDAO extends BaseDAO { c/%GfB[w0
n{=Ot^
";
publicList getUserByName(String name)throws /< Dtu UM
?y,KN}s_
HibernateException; [_*?~
`:d\L
H
publicint getUserCount()throws HibernateException; A2.4#Qb'
fsWPU]\)
publicList getUserByPage(Page page)throws 4D6LP*
kJ)Z{hy
HibernateException; Ob]J!.
CDT;AdRw7
} #<es>~0!
me90|GOx+
I")mg~f
gCbS$Pw
sIRfC<
/P
java代码: )GOio+{H
=+H,}
Dy{lgT 0k
/*Created on 2005-7-15*/ :W$-b
package com.adt.dao.impl; -4obX
2` Ihrz6
import java.util.List; k|$?b7)"@
bpa'`sf
import org.flyware.util.page.Page; Lc(eY{CY
[{zfI`6
import net.sf.hibernate.HibernateException; BY@l:y4
import net.sf.hibernate.Query; bQdu= s[
Rpj{!Ia
import com.adt.dao.UserDAO; N9~'\O$'7
x#hSN|'"
/** [J55%N;#1
* @author Joa TV/ EC#48
*/ >uFFTik
public class UserDAOImpl extends BaseDAOHibernateImpl whFJ]
4ZkaH(a1
implements UserDAO { Xm<|m#
+]Ev
/* (non-Javadoc) DeI3(o7
* @see com.adt.dao.UserDAO#getUserByName t(}g;O-
7v}(R:*
(java.lang.String) BCX2C
*/ Nnfq!%
publicList getUserByName(String name)throws N(P2Lo{JF
[MF&x9Ss?%
HibernateException { GtKSA#oYZB
String querySentence = "FROM user in class RL*b47,
wM}AWmH
com.adt.po.User WHERE user.name=:name"; Kd*=-
Query query = getSession().createQuery nuw7pEW@?
t
>Rh
(querySentence); n*9nzx#q
query.setParameter("name", name); 2I7|hZ,
return query.list(); o3:BH@@
} q``/7
Hxn#vAc
/* (non-Javadoc) !t?5U_on
* @see com.adt.dao.UserDAO#getUserCount() |O;vWn'U2
*/ ~.z82m
publicint getUserCount()throws HibernateException { )"_&CYnd
int count = 0; fr}.#~{5Y
String querySentence = "SELECT count(*) FROM o
^ 08<
2s}G6'xE]P
user in class com.adt.po.User"; MjbgAH-
Query query = getSession().createQuery QY*F(S,\
M^G9t*I
(querySentence); 9U3 .=J
count = ((Integer)query.iterate().next <@c@`K
g!Ui|]BI9
()).intValue(); # hw;aQ
return count; |W}D_2
} 0 c]]
`#l1
/* (non-Javadoc) YD0j&@.
* @see com.adt.dao.UserDAO#getUserByPage m%c]+Our`
5x!rT&!G
(org.flyware.util.page.Page) ):fu]s"
*/ <v?2p{U%
publicList getUserByPage(Page page)throws y2 R\SL,
H|/"'t
OZ
HibernateException { VO /b&%
String querySentence = "FROM user in class +wZ|g6vMct
=&~ K;=:
com.adt.po.User"; n*caP9B
Query query = getSession().createQuery V(Cxd.u
6XnUs1O
(querySentence); o\fPZ`p-m~
query.setFirstResult(page.getBeginIndex()) RFq=`/>dG
.setMaxResults(page.getEveryPage()); X.ZG-TC
return query.list(); iO$ ?No
} [7 t
C8=r sh
} ->Fsmb+R
U&SSc@of
9t8ccr
A,c_ME+DVB
O`Htdnu
至此,一个完整的分页程序完成。前台的只需要调用 SZ:R~4 A
zoBp02j
userManager.listUser(page)即可得到一个Page对象和结果集对象 r4fd@<=g
]hRs -x
的综合体,而传入的参数page对象则可以由前台传入,如果用 JURg=r]LI
iF_u/#
webwork,甚至可以直接在配置文件中指定。 #c9MVQ_
b#n
下面给出一个webwork调用示例: 65tsJ"a<
java代码: >fD%lq;
-VP_Aw$
%VE FruM
/*Created on 2005-6-17*/ *2/6fhI[p
package com.adt.action.user; "B9zQ,[Q
Z7 ++c<|p
import java.util.List; b,47
EJ}
h7S;
4]
import org.apache.commons.logging.Log; 6U,:J'5gP
import org.apache.commons.logging.LogFactory; Q+'fTmT[,
import org.flyware.util.page.Page; !/1~
O#<S\66
import com.adt.bo.Result; y^ D3}ds
import com.adt.service.UserService; u,~+ho@
import com.opensymphony.xwork.Action; ^ '_Fd
[q^pMH#U"
/** !e~d,NIy
* @author Joa aHPx'R
*/ ob/HO(h3
publicclass ListUser implementsAction{ oWggh3eXk
D\E"v,Y\+O
privatestaticfinal Log logger = LogFactory.getLog ~/Y8wxg
.tsXQf
(ListUser.class); ~`5[Li:eP
Psm9hP :m
private UserService userService; |T-Ytuy8
AP9\]qZ(7
private Page page; m"o=R\C
qj^A
privateList users; cca]@Ox]
}IQ! [T5
/* [geT u
* (non-Javadoc) 0|{":i_s
* 1uzK(j8w
* @see com.opensymphony.xwork.Action#execute() )-1$y+s>
*/ T,B%iZ gCh
publicString execute()throwsException{ ) P|/<>z
Result result = userService.listUser(page); k"cKxzB
page = result.getPage(); G$~hAZ
users = result.getContent(); 3Q,p,
return SUCCESS; McN'J.Sxp
} Rli`]~!w
BJqb'Hjd
/** |r4&@)
* @return Returns the page. [mF=<G"
*/ {@Z*.G^
public Page getPage(){ $$R->
return page; 8:]5H}Hi
} lg@q}
]1
o
Y<vKs^
/** z] |Y
* @return Returns the users. qLB(Th\&'
*/ 'NnmLM(oh
publicList getUsers(){ T n,Ifo3
return users; 2XeN E[
} PG'I7)Bv
2 xi@5;!
/** W#^p%?8pR
* @param page ?MiMwVR
* The page to set. `$/M\aM%
*/ x
o72JJ
publicvoid setPage(Page page){ 3>z+3!I z
this.page = page; uW,rmd
} @!(V0 -
L.a~vk
1
/** ],wzZhA
* @param users O^R^Aw
* The users to set. <q|eG\01S
*/ XsMETl"Av4
publicvoid setUsers(List users){ =I+5sCF{g
this.users = users; RP wP4Z
} X<H+Z2d
~>}7+p
?;
/** Ll^9,G"Tt
* @param userService <a2Kc '
* The userService to set. PU\@^)$
*/ Ki3wqY
publicvoid setUserService(UserService userService){ eBW]hwhKzM
this.userService = userService; oXqx]@7
} jLBwPI_g
} o5NrDDH
E8We2T[^M
|U="B4
td2bL4
q -^Z=,<
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, }5"19
Go?
T9gQq
7(l
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 s06R~P4
yMf["AvG
么只需要: iHyA;'!Os
java代码: qV@H u/;
3.
g-V
j<i:rk|
<?xml version="1.0"?> VHU,G+ms
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork JZcW? Or
.eDI ZX
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &E!-~'|z
B 6,X)
1.0.dtd"> Q__1QUu
i)d'l<RA
<xwork> R<1[hH9"o
/?:]f
<package name="user" extends="webwork- p5=VGKp
eadY(-4|I-
interceptors"> 'gz@UE1
@nF#\
<!-- The default interceptor stack name _"[O=h:
fkr;
a`<W
--> <1E*wPm8
<default-interceptor-ref Gt?ckMB
mg4:N
name="myDefaultWebStack"/> zMN4cBL9m
skfFj&_T
<action name="listUser" )TgjaR9G
ZlYb8+rW
class="com.adt.action.user.ListUser"> 3)qtz_,H/g
<param <}Rr C#uiA
^VB_>|UN4
name="page.everyPage">10</param> -"3<Ll
<result N/mC,7Q
A*hc
w
name="success">/user/user_list.jsp</result> `]g}M,
</action> affig
!8>tT
</package> F!yejn
[
?gOZY\[ma
</xwork> .e%B'
Nv_"?er+y
<rF Y$
?x
2qUC@d<K
>=U n=Q%
B1a&'WX?
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 68jq1Y
Pv
{\f`s^;8{
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。 K3^N_^H
&`[Dl(W
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 c1p*}T
fmj-&6
]i@VIvYq
Flzl,3rW4
*a4nd_!
我写的一个用于分页的类,用了泛型了,hoho hSDuByoi
S[cVoV
java代码: c)fTI,.$
O
hcPlr
geu8$^
package com.intokr.util; z,B'I.)M
!B{N:?r
import java.util.List; CEos`
KBo/GBD]|
/** nr<&j#!L
* 用于分页的类<br> hUy\)GsT
* 可以用于传递查询的结果也可以用于传送查询的参数<br> G>0S(M)
* u9"1%
* @version 0.01 KCkA4`IeM
* @author cheng v-@xO&<
*/ CCZ]`*wJ
public class Paginator<E> { 9
&~Rj 9
privateint count = 0; // 总记录数 zy9# *gGq
privateint p = 1; // 页编号 ,kKMUshBi
privateint num = 20; // 每页的记录数 |JW-P`tL0
privateList<E> results = null; // 结果 JY tM1d
Pz1[ b$%
/** 0UvN ws
* 结果总数 (s`yMUC+
*/ M[R\URu8
publicint getCount(){ 7$7Y)&\5w
return count; [/ E_v gZ
} wDV%.Cc
T7=~l)I
publicvoid setCount(int count){ agFWye
this.count = count; D'Gmua]I
} yA+:\%y$
0g@
8x_3
/** c91rc>
* 本结果所在的页码,从1开始 5M2G ;o
* K?q1I<94
* @return Returns the pageNo. S5Q$dAL
*/ {uRnZ/m
publicint getP(){ YRYAQj/7
return p; cM;&$IjCt
} ^L(}c O
iS^IqS
/** /CAi%UH,F
* if(p<=0) p=1 S&@uY#_(*T
* xhIC["z5
* @param p FXPw 5
*/ $b/oiy!=|3
publicvoid setP(int p){ DM%4V|F"
if(p <= 0) PZRm.vC)k
p = 1; %<q l
this.p = p; gekW&tRie
} b"y][5VE
=M'y& iz-
/** $!<J_d*
* 每页记录数量 A({8p
*/ nJ`JF5tI
publicint getNum(){ &zr..i4O
return num; 8qfg=mu+%
} ZgL4$%
MeqW/!72$L
/** Fa$ pr`
* if(num<1) num=1 qsUlfv9L6
*/ 7
Znr2I
publicvoid setNum(int num){ \KmjA)(
if(num < 1) eGS1% [
num = 1; MH`H[2<\!,
this.num = num; 0SXWt? }
} hgCeU+ H
0.-2FHc9L
/** J}qk:xGL
* 获得总页数 c_]$UM[7L
*/ 95,y@~*]
publicint getPageNum(){ >`a)gky%~
return(count - 1) / num + 1; _W4i?Bde
} \$2E
Kv[,!P"Y
/** gg(^:`+
* 获得本页的开始编号,为 (p-1)*num+1 *BYSfcX6
*/ /s>ZT8vaAs
publicint getStart(){ sY=fS2b#)
return(p - 1) * num + 1; _'k?9eN`
} =~% B}T
7CzZHkTg
/** 0sq1SHI{
* @return Returns the results. 5rqjqfFa
*/ cjf}yn
publicList<E> getResults(){ :Xv3< rS<
return results; !Re/W
ykY
} ,>n 4
`A
z)'dDM D"
public void setResults(List<E> results){ hSc$Sa8
this.results = results; b<qv
/t)$
} ysfR@ sH7
w8*+l0
public String toString(){ 1%|+yu1
StringBuilder buff = new StringBuilder ^{["]!f#
Ep0L51Q
(); .9WJ/RKZ\D
buff.append("{"); UK2Y<\vD
buff.append("count:").append(count); x"~F=jT
buff.append(",p:").append(p); DNdwMSwp
buff.append(",nump:").append(num); C:g2E[#
buff.append(",results:").append P$Y<
g/s4
nJny9g
(results); HHD4#XcU
buff.append("}"); '+NmHu:q
return buff.toString(); v9Oyboh(y
} 4^VY
F8?&Ql/hdz
} dWE[*a\g
J4h7]
qt
`,4"[6S