Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 bi",DKU{l
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T2.[iD!A
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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 3Z me?o*bY
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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 liLhvcd
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分页支持类: 0WSZhzNyY
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java代码: g3{UP]Z71
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package com.javaeye.common.util; "8cI]~V
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import java.util.List; vlEW{B;)Z
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publicclass PaginationSupport { gJrWewEe
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publicfinalstaticint PAGESIZE = 30; W-&V:S{<
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privateint pageSize = PAGESIZE; p nI=
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privateList items; 0jjtx'F
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privateint totalCount; iI7ocyUv
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privateint[] indexes = newint[0]; 3/Z>W|w#w
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privateint startIndex = 0; t:vBVDkD
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public PaginationSupport(List items, int Qs59IZ
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totalCount){ vW vu&3tx
setPageSize(PAGESIZE); DU]KD%kl
setTotalCount(totalCount); qdv O>k3
setItems(items); H, :]S-T
setStartIndex(0); c>^(=52Q
} %Pt){9b
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public PaginationSupport(List items, int &TA{US3~
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totalCount, int startIndex){ -rm[.
setPageSize(PAGESIZE); bGgpPV
setTotalCount(totalCount); e3 :L]4t
setItems(items); o,*D8[
setStartIndex(startIndex); uZ-ZZE C
}
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public PaginationSupport(List items, int S5y.H
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totalCount, int pageSize, int startIndex){ fbOqxF"?we
setPageSize(pageSize); )=29Hm"
setTotalCount(totalCount); rZaO^}u]
setItems(items); Z
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setStartIndex(startIndex); fC*cqc~{@
} -,p=;t#(
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publicList getItems(){ 7>F{.\Z
return items; +>vKI8g*RH
} DR:$urU$
}AJoF41X
publicvoid setItems(List items){ hp9U
this.items = items; A!x &,<
} a6e{bAuq
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publicint getPageSize(){ Ihf :k_;
return pageSize; y*vSt^
} PMB4]p%o
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publicvoid setPageSize(int pageSize){ }shxEsq
this.pageSize = pageSize; VLkAsM5}%
} [{BY$"b#:
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publicint getTotalCount(){ L1/`/
return totalCount; Cg]),S
} Im/tU6ybV
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publicvoid setTotalCount(int totalCount){ er)I ".|
if(totalCount > 0){ Xzf,S;XV~
this.totalCount = totalCount; #m{*]mY@
int count = totalCount / <TRhn z
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pageSize; NBc^(F"
if(totalCount % pageSize > 0) '"\M`G
count++; k<^M >` $
indexes = newint[count]; # Q^".#
for(int i = 0; i < count; i++){ }a6t <m`V
indexes = pageSize * VoZ{ I{>|
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i; @q/g%-WNz
} Q[7 i
}else{ #[lhem] IC
this.totalCount = 0; Wa<<"x$
} i!?gga
} `9J9[!+!`
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publicint[] getIndexes(){ tZ9i/ =S
return indexes; $Xu3s~:S
} 1Qf}nWy
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publicvoid setIndexes(int[] indexes){ 67&
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this.indexes = indexes; &S*~EM.l8
}
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publicint getStartIndex(){ w#9KtW,tt
return startIndex; 6&eXQl
} :V)jm`)#+
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publicvoid setStartIndex(int startIndex){ ^}d]O(
if(totalCount <= 0) P6 OnE18n
this.startIndex = 0; JF 4A
elseif(startIndex >= totalCount) -Qn7+?P
this.startIndex = indexes ]19VEH
*n? 1C"l
[indexes.length - 1]; {G:y?q'z
elseif(startIndex < 0) &oS$<
this.startIndex = 0; _]>1(8_N
else{ YzI;)
this.startIndex = indexes D%YgS$p[M$
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[startIndex / pageSize]; G-Tmk7m
} |HAJDhM,l
} G:1'}RC :
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publicint getNextIndex(){ Iv6 q(c
int nextIndex = getStartIndex() + {q?&h'#y
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pageSize; Bvn3:+(47
if(nextIndex >= totalCount) neDXzMxF
return getStartIndex(); G:=hg6'
else 3`HK^((o
return nextIndex; WD[eoi
} my.EvN
u#E'k
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publicint getPreviousIndex(){ \WCQ>c?~
int previousIndex = getStartIndex() - v~P,OP("c
o|(5Sr&H
pageSize; %X{EupiFA
if(previousIndex < 0) @Iv;y*y
return0; fe?Z33V
else }~XWtWbd-
return previousIndex; 'jtC#:ePK
} Wp=3heCa6
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} QOF@DvQ
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抽象业务类 '-;[8:y.
java代码: Z',!LK!
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/** e`D}[G#
* Created on 2005-7-12 /~[Lr
*/ 1sQIfX#2f
package com.javaeye.common.business; ~7P)$[
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import java.io.Serializable; IU%|K~_n
import java.util.List; NI >%v
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import org.hibernate.Criteria; ,^#Jw`w^
import org.hibernate.HibernateException; y/lF1{}5
import org.hibernate.Session; S(Yd.Sp
import org.hibernate.criterion.DetachedCriteria; E
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import org.hibernate.criterion.Projections; u/zBz*zh
import l90mM'[
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6
org.springframework.orm.hibernate3.HibernateCallback; !_<6}:ZB
import %qP[+N&
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org.springframework.orm.hibernate3.support.HibernateDaoS P#,u9EIJ
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upport; kmI0V[Y
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import com.javaeye.common.util.PaginationSupport; yB*,)x0
@
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public abstract class AbstractManager extends `2s!%/
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HibernateDaoSupport { WNjwv/
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privateboolean cacheQueries = false; kSQ8kU_w+
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privateString queryCacheRegion; n_8[bkbi
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publicvoid setCacheQueries(boolean ~4S$+*'8
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cacheQueries){ b'H'QY
this.cacheQueries = cacheQueries; k*.]*]
} I2ek`t]
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publicvoid setQueryCacheRegion(String g,ZA\R~
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queryCacheRegion){ &1xCPKIr
this.queryCacheRegion = xvr5$x|h
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queryCacheRegion; |y\Km
} (!os&/",
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publicvoid save(finalObject entity){ [m
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getHibernateTemplate().save(entity); pm&THd
}
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publicvoid persist(finalObject entity){ '=\}dav!
getHibernateTemplate().save(entity); h~MV=7
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} Y Y:BwW:
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publicvoid update(finalObject entity){ JE?p'77C
getHibernateTemplate().update(entity); V|7YRa@
} j]a$RC#
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publicvoid delete(finalObject entity){ \INH[X#>
getHibernateTemplate().delete(entity); )*|/5wW1
} j=_rUc'Me
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publicObject load(finalClass entity, T5BZD
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finalSerializable id){ wucdXj{%
return getHibernateTemplate().load l.[pnL D
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(entity, id); +Q*`kg'
} !,WGd|oJ
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publicObject get(finalClass entity, 30Yis_l2h
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finalSerializable id){ g8),$:Uw
return getHibernateTemplate().get )^h6'h`
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(entity, id); ?Cq7_rq
} cw;wv+|k
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publicList findAll(finalClass entity){ #m+!<
return getHibernateTemplate().find("from l{3B}_,
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" + entity.getName()); uFd$*`jS
} q^@*{H
+Qs]8*^?;
publicList findByNamedQuery(finalString >%JPgr/
8
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namedQuery){ jXcJ/g(X3
return getHibernateTemplate )n/%P4l
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().findByNamedQuery(namedQuery);
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} 0MQ= Rt
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publicList findByNamedQuery(finalString query, z(PUoV:?
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finalObject parameter){ .{Y;6]9[
return getHibernateTemplate ]wQ!ZG?)
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().findByNamedQuery(query, parameter); [;E%o^/^
} ?5|;3N/zt
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publicList findByNamedQuery(finalString query, ,N/@=As9$
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finalObject[] parameters){ =O/Bte.
return getHibernateTemplate <QtZ6-;_f
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().findByNamedQuery(query, parameters); 8$Q`wRt(%
} ?M2(80
;#B(L=/
publicList find(finalString query){ I8*VM3
return getHibernateTemplate().find !Jg;%%E3:i
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(query); 4"@<bKx
} aCQtE,.
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publicList find(finalString query, finalObject _8K+iqMZG
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parameter){ a|ft l&uk
return getHibernateTemplate().find KaIKb=4L|
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(query, parameter); owVvbC2<b(
} H$6RDMU
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public PaginationSupport findPageByCriteria S"Al[{
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(final DetachedCriteria detachedCriteria){ 5Iu5N0cn
return findPageByCriteria bT,:eA
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &|SWy
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} ]A4=/6`g?b
=;Id["+
public PaginationSupport findPageByCriteria K2m>D=w
h!"2Ux3!x
(final DetachedCriteria detachedCriteria, finalint 8K8u|]i
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startIndex){ G1:}{a5i_
return findPageByCriteria EIi<g2pM(
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(detachedCriteria, PaginationSupport.PAGESIZE, ~cz}C("Z
!}*N';
startIndex); ,(jJOFf
} \u=d`}E
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public PaginationSupport findPageByCriteria 2Gyq40
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(final DetachedCriteria detachedCriteria, finalint %wD#[<BGn>
*MJm:
pageSize, v|?@k^Ms
finalint startIndex){ 'Kelq$dn#
return(PaginationSupport) HKN|pO3v
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getHibernateTemplate().execute(new HibernateCallback(){ dQX-s=XJ
publicObject doInHibernate , c.^"5
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(Session session)throws HibernateException {
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Criteria criteria = u#05`i:Z
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detachedCriteria.getExecutableCriteria(session); .j6udiv5
int totalCount = 2j\_svw'
OT#@\/>
((Integer) criteria.setProjection(Projections.rowCount KbJ6U75|f
o<g?*"TRh
()).uniqueResult()).intValue(); aRd~T6I
criteria.setProjection 6]4~]!
+cpb!YEAb
(null); 1nVQYqT_
List items = 2g(_Kdj*{
FT).$h~+4
criteria.setFirstResult(startIndex).setMaxResults iIfiv<(ChM
IPot][ N>
(pageSize).list(); +Z#=z,.^
PaginationSupport ps = K5>3
]&'!0'3`
new PaginationSupport(items, totalCount, pageSize, o.s'0xP]
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startIndex); ZbRRDXk!
return ps; )1 <0c@g=
} ;R$G.5h
}, true); A#>wbHjWF
} DJ ru|2
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public List findAllByCriteria(final +'H[4g`
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DetachedCriteria detachedCriteria){ ^}j~:EZb
return(List) getHibernateTemplate b1xE;0uR
Y;af|?U*6:
().execute(new HibernateCallback(){ KFM[caKeJO
publicObject doInHibernate bGh&@&dHr
hvt]VC]]
(Session session)throws HibernateException { tqZ91QpW
Criteria criteria = s/1r{;q
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detachedCriteria.getExecutableCriteria(session); _/[qBe
return criteria.list(); +|?a7qM
} &BVUK"}P
}, true); mR}8} K]L
} )L<.;`g4x
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public int getCountByCriteria(final Kq7r+A
R P{pEd
DetachedCriteria detachedCriteria){ Owp]>e
Integer count = (Integer) K#FD$,c~
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getHibernateTemplate().execute(new HibernateCallback(){ 1$Up7=Dr=
publicObject doInHibernate 6/!:vsa"3
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(Session session)throws HibernateException { O"9t,B>=i
Criteria criteria = zJ`u>:*$
,7nu;fOT[
detachedCriteria.getExecutableCriteria(session); 97c0bgI!+
return =B&|\2`{)
(o>N*?,}
criteria.setProjection(Projections.rowCount ~|u;z,\
@Y~gdK
()).uniqueResult(); Y XhZWo{B
} 'O%*:'5k
}, true); HoBx0N9\2
return count.intValue(); .M6. ]H
} GTs,?t16/
} tmGhJZ2j
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用户在web层构造查询条件detachedCriteria,和可选的 EXdX%T\
l4gH]!/@
startIndex,调用业务bean的相应findByCriteria方法,返回一个 q\tr&@4iC
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PaginationSupport的实例ps。 a-*sm~u
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ps.getItems()得到已分页好的结果集 \:'GAByy
ps.getIndexes()得到分页索引的数组 "t2T*'j{
ps.getTotalCount()得到总结果数 zkt~[-jm}
ps.getStartIndex()当前分页索引 CW`^fI9H
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 N\|B06X
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pIIp61=$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 WjBml'^RY
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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 Iq|h1ie
m+
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一下代码重构了。 Cq@7oi]W0
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我把原本我的做法也提供出来供大家讨论吧: H_g]q
ImQ-kz?b
首先,为了实现分页查询,我封装了一个Page类: 4#t'1tzu#
java代码: &"u(0q
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/*Created on 2005-4-14*/ !19T=p/:$
package org.flyware.util.page; U["<f`z4\
3 EAr=E]
/** JP!e'oWxi
* @author Joa ln<[CgV8
* /5%'q~
*/ 2k!uk6
publicclass Page { &[`24Db
}[%F
/** imply if the page has previous page */ %2RXrH2&H
privateboolean hasPrePage; QeY+imM
0ytAn+/"x
/** imply if the page has next page */ x~'_;>]r_
privateboolean hasNextPage; [\F:NLjiUy
4][VK/v+
/** the number of every page */ DN9x<%/-
privateint everyPage; !/`AM<`o
r
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/** the total page number */ '"Cqq{*
privateint totalPage; ks$5$,^T2o
<F`9;WX
/** the number of current page */ 02 FLe*zQ
privateint currentPage; 06NiH-0O
.}E<,T
/** the begin index of the records by the current 5hqXMs
ko.%@Y(=
query */ z:UkMn[
privateint beginIndex; 0gyvRM@ x[
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EAY+#>L*
/** The default constructor */ q2k}bb +
public Page(){ !}A`6z
~#EXb?#uS
} gISA13
SFzoRI=qG
/** construct the page by everyPage uUl ;}W
* @param everyPage c[1{>z{G
* */ jKP75jm
public Page(int everyPage){ .yzXw8~S
this.everyPage = everyPage; :wzbD,/M
} ?@A@;`0Y
@#"K6
/** The whole constructor */ ~+\A4BW
public Page(boolean hasPrePage, boolean hasNextPage, b5p;)#
}+ W5Snx
=M{&g
int everyPage, int totalPage, wQ-BY"cK\
int currentPage, int beginIndex){ KW0KXO06a
this.hasPrePage = hasPrePage; c5CxR#O
this.hasNextPage = hasNextPage; 7F~Jz*,B*W
this.everyPage = everyPage; b6 g9!
this.totalPage = totalPage; 9~,!+#
this.currentPage = currentPage; i(u zb<
this.beginIndex = beginIndex; a"+/fC`
} CE183l\
yl<=_Q
/** 9<Zm}PE32
* @return VQ~eg wJL
* Returns the beginIndex. 84(jg P
*/ 1_~'?'&^
publicint getBeginIndex(){ 7Aw <:
return beginIndex; J_
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} 8=\k<X{`
{YzpYc1
/** J(~xU0gd'
* @param beginIndex ^[HX#JJ~
* The beginIndex to set. |bRi bB
*/ ZZL%5{w_
publicvoid setBeginIndex(int beginIndex){ Y\H4.$V
this.beginIndex = beginIndex; Yv*i69"
} "|
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/** }Ny~.EV5^
* @return I1ibrn
* Returns the currentPage. yC}x6xG
*/ g2lv4Tiq-
publicint getCurrentPage(){ )P/~{Ci:T&
return currentPage; lr,i5n{6
} i;)r|L`V?
+c'I7bBr
/** Mf:x9#
* @param currentPage F fzY3r+
* The currentPage to set. wRWKem=
*/ |?fc]dl1]
publicvoid setCurrentPage(int currentPage){ "MT{t><
this.currentPage = currentPage; m<9W#
} ,g)9ZP.F
w68VOymD/
/** I>3G"[t
* @return RML'C:1
* Returns the everyPage. lce~6}
*/ *
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publicint getEveryPage(){ el0W0T
return everyPage; (7aE!r\Ab
} Bq:: 5,v
7"_gX
/** I'cM\^/h
* @param everyPage ,wra f#UdP
* The everyPage to set. 0xutG/-&N
*/ 64!V8&Ay
publicvoid setEveryPage(int everyPage){ !91<K{#A{
this.everyPage = everyPage; ]_)=xF19
} HPWjNwM
PJcz] <
/**
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* @return [TpW$E0H
* Returns the hasNextPage. #lm1"~`5
*/ 7W#9ki1
publicboolean getHasNextPage(){ w*N9p8hb]
return hasNextPage; ]| =#FFz
} v3jx2Z
UUql"$q
/** yIThzyS
* @param hasNextPage (au7wI{
* The hasNextPage to set. (aH_K07
*/ 7<ES&ls_
publicvoid setHasNextPage(boolean hasNextPage){ q}R"
this.hasNextPage = hasNextPage; |7T!rnr
} /9yA.W;
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/** ph1veD<ZZ
* @return \E<)B#
* Returns the hasPrePage. 0:Lm=9o
*/ iNs
publicboolean getHasPrePage(){ hAZ"M:f
return hasPrePage; I-q@@!=
} #P6;-d@a
{=d\t<p*n
/** 58My6(5y
* @param hasPrePage <BN)>NqM
* The hasPrePage to set. dTP$7nfe
*/ :XZ
publicvoid setHasPrePage(boolean hasPrePage){ .~
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this.hasPrePage = hasPrePage; p>p=nL K
} iyhB;s5Rgw
ffyKAZ{]po
/** Xl%&hM
* @return Returns the totalPage. VuW&CnZ
* (5N&bh`E
*/ R=M${u<t
publicint getTotalPage(){ yz2NB?)
return totalPage; g<{W\VOPm
} |3g:q
C31SXQ
/** [w)6OT
* @param totalPage 7<?v!vQ}-
* The totalPage to set. Hca)5$yL
*/ jKu"Vi|j>
publicvoid setTotalPage(int totalPage){ A|@d4+
this.totalPage = totalPage; 2S8/
lsB
} ;z7iUke0%
'bg%9}
} 9W7H",wR
GRj{*zs
gGdZ}9
S*CRVs
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ziy~~J
zn3i2MWS
个PageUtil,负责对Page对象进行构造: [w~1e)D
java代码: ?z60b=f8
^IM;D)X&:
I#f<YbzD
/*Created on 2005-4-14*/ \Jv6Igu
package org.flyware.util.page; PHD$E s
=N
n0)l
import org.apache.commons.logging.Log; _Oq (&I
import org.apache.commons.logging.LogFactory; g!%csf
c66Iy"
/** :/Nz' n
* @author Joa ou-5iH?
* D1lHq/
*/ !=0N38wA
publicclass PageUtil { x<=+RYz#^:
Xf9VW}`*8
privatestaticfinal Log logger = LogFactory.getLog 8c3X9;a
2Sb~tTGz79
(PageUtil.class); f5/ba9nI
q@u$I'`Bs
/** h_d!G+-]
* Use the origin page to create a new page ]]%CO$`T[
* @param page fi#o>tVyJ
* @param totalRecords 4(YKwY2_L
* @return poHDA=#
3
*/ '&T4ryq3"
publicstatic Page createPage(Page page, int lTdYPqMi
r"rID
RQ"
totalRecords){ Mp$ uEi
return createPage(page.getEveryPage(), $K8ZxH1z@
OH*[
page.getCurrentPage(), totalRecords); bU:"dqRm<
} ^#%$?w>wI
+V7*vlx-
/** 5'>(|7~%\
* the basic page utils not including exception f+$/gz
x_(B7ob
handler NCSb`SC:
* @param everyPage /tP"r}l
* @param currentPage !OWV* v2
* @param totalRecords 4y21v|(9
* @return page C`knFGb
*/ OBN]bvCJ
publicstatic Page createPage(int everyPage, int n2Ycq&O
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currentPage, int totalRecords){ Yq)
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everyPage = getEveryPage(everyPage); S)$ES6]9/
currentPage = getCurrentPage(currentPage); v=SC*
int beginIndex = getBeginIndex(everyPage, iQin|$F_O
wTIOCj
currentPage); /2?GRwU~P
int totalPage = getTotalPage(everyPage, w},k~5U^s
0V srAV0
totalRecords); l!q i:H<=1
boolean hasNextPage = hasNextPage(currentPage, >48zRi\N
8<?60sj
totalPage); S <|e/![@
boolean hasPrePage = hasPrePage(currentPage); Ql\{^s+
2lHJ&fck<
returnnew Page(hasPrePage, hasNextPage, ='OPU5(;O
everyPage, totalPage, a*S4rq@
currentPage, R[Kyq|UyVr
KH2a 2
beginIndex); ^i#q{@g
} cD2}EqZ 9
o $p*C
privatestaticint getEveryPage(int everyPage){ 0xC{Lf&
return everyPage == 0 ? 10 : everyPage; HK5\i@G+<
} P*R`3Y,
\\x``*
privatestaticint getCurrentPage(int currentPage){ +~02j1Jx
return currentPage == 0 ? 1 : currentPage; 01#a
} o& $Fc8bH
{Sd{|R_
privatestaticint getBeginIndex(int everyPage, int [Fr.ik
LYavth`@h
currentPage){ Eh0R0;l5>
return(currentPage - 1) * everyPage; *wyaBV?*K
} J0lTp /
=JNoC01D
privatestaticint getTotalPage(int everyPage, int qV^,muyoG
0 Co_,"
totalRecords){ WQ =C5^u
int totalPage = 0; _i6G)u&N
#$X_,P|D
if(totalRecords % everyPage == 0) |ay W _5}
totalPage = totalRecords / everyPage; HRje4=:
else I`E9]b(w
totalPage = totalRecords / everyPage + 1 ; >K;p+( <6
:%)l*[
return totalPage; SAc}5.
} m_Z%[@L
XrtB&h|C
privatestaticboolean hasPrePage(int currentPage){ }N*6xr*X+
return currentPage == 1 ? false : true; i@Q)`>4
} 4wMKl6mL
+'hcFZn(T
privatestaticboolean hasNextPage(int currentPage, p@NE^aMn
qS|bpC0x
int totalPage){ *#+XfOtF
return currentPage == totalPage || totalPage == |AuN5|obI
Nx;U]O6A
0 ? false : true; ?7/n s>}
} R.*KaCA
W<u63P
$
;~G
} P0DvZV8
I%b,
H`
*ukugg.
BRFA%FZ,
%{5mkO&,2
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。 FSIV\ u
Mfuw y
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 92bvmP*o4
9eH(FB
做法如下: 6|rqsk
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2zh?]if
H)G ^ Y1
的信息,和一个结果集List: ,cYU
java代码: ul>$vUbyf
G?8LYg!-
8@|+-)t
/*Created on 2005-6-13*/ [&j!g
package com.adt.bo; j#9p0[
ShxB!/s
import java.util.List; t+W+f
&M*&oi (
import org.flyware.util.page.Page; ~aNK)<Fznd
[l:3F<M
/** wH3FCfvm
* @author Joa /4<eI3Z
*/ |/Am\tk#13
publicclass Result { uw&GXOzew9
OTl\^!
private Page page; `BmAu[(e&
~}i&gd|(
private List content; \@8$tQCZ
2N9
BI-a
/** \3hhM}6)DM
* The default constructor Gc<J x|Q7
*/ 5<<e_n.2q
public Result(){ ^g$k4
super(); 5Q^
L"&0
} h3h2 KqM'
5tX|@Z:
z
/** ~Wm`SIV
* The constructor using fields l=`)yc.
* ;l[/<J
* @param page K@Twiw~rB
* @param content `f}}z5
*/ cH.T6u_%
public Result(Page page, List content){ |g}!
F-
this.page = page; zT6ng#
this.content = content; .1XZ9M
} Hz`rw\\Xq
B)Hs>Mh|W
/** ! %S9H2Lv
* @return Returns the content. p)(mF"\8=
*/ .[? E1we
publicList getContent(){ FZ6.<wN
return content; :=UiEDN@
} Psp3~Kg
)**k3u
t4
/** !Ui3}
* @return Returns the page. JR<#el
*/ ;<1O86!
public Page getPage(){ R|Z $aHQ
return page; E<1^i;F
} !:,d^L!bh
kZs
/** ?>N82#9Q
* @param content ?"$W=*P\o
* The content to set. 4d)w2t?H%
*/ L"rLalUw
public void setContent(List content){ 3Wrl_V
this.content = content; \7nlwFAO
} xAMj 16ZF
Oj:O-PtN2
/** `zAV#
* @param page %np b.C|+
* The page to set. y@ J\h8_
*/ 4xuL{z;\
publicvoid setPage(Page page){ !bFa\6]q
this.page = page; h6}oRz9=g
} B!K{y>|.
} c=<d99Cu!
C"PN3>x}j
hun
LV8z
a5{CkM&,(
#m1e_[
2. 编写业务逻辑接口,并实现它(UserManager, UB@>i3
6|r`
k75.
UserManagerImpl) :
FF:{&d
java代码: 'm# -)R!
j
wlmWO6
W1f]A#t<
/*Created on 2005-7-15*/ wb2N$Ew=
package com.adt.service; + ^{;o0kcx
M@UkXA}
import net.sf.hibernate.HibernateException; :Qh5ZO&G0
NDglse
import org.flyware.util.page.Page; CsS0(n(x
y4$UPLm
import com.adt.bo.Result; Z`v6DfK}
O66\s q
/** &ME[H
* @author Joa %?J\P@
*/ 2/RK
pl &
publicinterface UserManager { e<dFvMO
G'q7@d{'
public Result listUser(Page page)throws <~!7? ak
Pk T&zSQA
HibernateException; W%hdS<b
RX4O1Z0
} )/PvaL
Hq8<g$
zh2$U
dZ|M
TKvUBy
yc8FEn!)&
java代码: =\e}fyuK
2w)0>Y(_
}P#%aE&-
/*Created on 2005-7-15*/ Mcj4GjV6:"
package com.adt.service.impl; b[$%Wg
wxB?}
import java.util.List; {g@Wd2-J}
$]:I1I
import net.sf.hibernate.HibernateException; k$y(H;XA
[4]lAxrRF
import org.flyware.util.page.Page; d{0b*l%
import org.flyware.util.page.PageUtil; @riCR<fF
EShc1KPqc
import com.adt.bo.Result; ?t$sju(\
import com.adt.dao.UserDAO; X?z5IL;rt
import com.adt.exception.ObjectNotFoundException; zLc.4k
import com.adt.service.UserManager; 1GN>,Lb:o
LN
]ks)
/** +2O('}t
* @author Joa m <IPi <
*/ l<<0:~+q
publicclass UserManagerImpl implements UserManager { QbP
W_)N
w-FZ`OA`D
private UserDAO userDAO; 9*GwW&M%1_
AT}}RE@vq
/** 5Qd |R
* @param userDAO The userDAO to set. 5)'
_3r
*/ x=Qy{eIe
publicvoid setUserDAO(UserDAO userDAO){ f)H6 nl7r
this.userDAO = userDAO; ~mOGNf?f
} 8 Mp2MZ*p
gZuk(
/* (non-Javadoc) N(vzxx^
* @see com.adt.service.UserManager#listUser %/>\`d?
+"Ih'bb`j
(org.flyware.util.page.Page) bITOA
*/ #HWz.Wb
public Result listUser(Page page)throws 7Gnslp?[U
%eGxQDIXg
HibernateException, ObjectNotFoundException { 0{F"b'h
int totalRecords = userDAO.getUserCount(); `I ,A7b
if(totalRecords == 0)
O*d&H;;
throw new ObjectNotFoundException ~QFD ^SoK
C$){H"#
("userNotExist"); JaKR#Y$+~
page = PageUtil.createPage(page, totalRecords); bYQ h{q
List users = userDAO.getUserByPage(page); 0bQaXxt|p
returnnew Result(page, users); Vo+d3
} {S%)GvrT
yT`[9u,
} 0aQtJ0e16
kFgN^v^t
6[$kEKOY=
"h_]it};C
zwR@^ 5^6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Wv_5sPqLW
7J~6J.m
询,接下来编写UserDAO的代码: hE\,4c1
3. UserDAO 和 UserDAOImpl: %1gJOV
java代码: bW;0E%_
)&1yt4
x6%
leiED'
/*Created on 2005-7-15*/ >s1FTB-$W
package com.adt.dao; d8<Lk9H9R
bv;&oc:r
import java.util.List; 6#T?g7\pyR
RKdf1C
import org.flyware.util.page.Page; E"!9WF(2t5
?=jmyDXH!
import net.sf.hibernate.HibernateException; b5Rjn1@
GC66n1- X
/** \hdR&f5q
* @author Joa o m`r^3,
*/ P{)H7B>
publicinterface UserDAO extends BaseDAO { *U.$=4Az
Y:&1;`FBZ
publicList getUserByName(String name)throws K6KEdXM4
cCFSPT2fq[
HibernateException; k^Tu9}[W1
<]/`#Xgh
publicint getUserCount()throws HibernateException; m}:";>?#
2n?\tOm(V
publicList getUserByPage(Page page)throws &~pj)\_
vNLf)B
HibernateException; 8V_
]}W
fpM4q
} U(-9xp+
daWmF
>4ebvM
0|
'97)c7E
LnZ*,>1Z
java代码: /4#.qq0\{c
F){f{-@)
j:"+/5rV8
/*Created on 2005-7-15*/ }!0,(<EsV
package com.adt.dao.impl; nf,>l0,,'
yZHQql%J
O
import java.util.List; [A|W0
*0 i
import org.flyware.util.page.Page; 4v3y3
(Ew o
import net.sf.hibernate.HibernateException; f<xF+wE
import net.sf.hibernate.Query; *`ehI_v :
1KruGq~
import com.adt.dao.UserDAO; ?XsL4HIx
Z{chAg\
/** 0vS%m/Zi-
* @author Joa <%J dQ82?
*/ |?s%8c'w=
public class UserDAOImpl extends BaseDAOHibernateImpl *{Wh-bc
J4j?rLR3p
implements UserDAO { [Qy]henK
*Zt)J8C
/* (non-Javadoc) ;PaB5TT(
* @see com.adt.dao.UserDAO#getUserByName TmKO/N@}
BS*cG>T
(java.lang.String) #Vv*2Mc
*/ o1Mb HBb
publicList getUserByName(String name)throws ?Y
)Qy,
< t>N(e
HibernateException { uWx/V+w
String querySentence = "FROM user in class PHfGl
aC]~
com.adt.po.User WHERE user.name=:name"; ?P<&8eY
Query query = getSession().createQuery )prpG !
GK95=?f~8;
(querySentence); &BG^:4b
query.setParameter("name", name); RduA0@g0
return query.list(); (d^pYPr{
} ~S|Vd
CEYHD ?9k8
/* (non-Javadoc) m %ET!+
* @see com.adt.dao.UserDAO#getUserCount() &lBfW$PZjk
*/ |xQj2?_z*
publicint getUserCount()throws HibernateException { {aGQ[MH\9
int count = 0; BRoi`.b:
String querySentence = "SELECT count(*) FROM z9h`sY~
'QeqWn
user in class com.adt.po.User"; 5y=X?hF~)
Query query = getSession().createQuery iA^w2K
A6lf-8ncx
(querySentence); GaRL]w
count = ((Integer)query.iterate().next l#:=zu
{zbH.V[
()).intValue(); i`2Q;Az_P6
return count; 7X|&:V.s|
} kG?tgO?*
wH|\;M{0V1
/* (non-Javadoc)
H.Jcp|k[;
* @see com.adt.dao.UserDAO#getUserByPage y>~=o9J_u
SjlkKulMF
(org.flyware.util.page.Page) e6sL N
*/ Mk@ _uPm
publicList getUserByPage(Page page)throws CG=#rc]vz
eqeVz`
HibernateException { Nj#!L~^h,
String querySentence = "FROM user in class CFul_qZ/e
htM5Nm[g
com.adt.po.User"; bGK&W;Myk
Query query = getSession().createQuery T%P0M*
w$Dp m.0(
(querySentence);
V }8J&(\
query.setFirstResult(page.getBeginIndex()) >/e#Z
h
.setMaxResults(page.getEveryPage()); ]lz,?izMR
return query.list(); >:OOuf#
} YI%7#L7C
Oq+C<}eg
} V_+3@C
%3xH<$Gq5
v{JCEb&wN
M_9|YjwS
Kwh3SU=L}
至此,一个完整的分页程序完成。前台的只需要调用 (5km]`7z
aEZl ICpU7
userManager.listUser(page)即可得到一个Page对象和结果集对象 Aba6/
YXV![gw0
的综合体,而传入的参数page对象则可以由前台传入,如果用 K<|b>PI.s
kZz;l(?0
webwork,甚至可以直接在配置文件中指定。 i"JF~6c<
Lb2Bu >
下面给出一个webwork调用示例: NNe'5q9
java代码: z W+wtYV4
,0-
4RTEXoXs
/*Created on 2005-6-17*/ YnJ=&21
package com.adt.action.user; ? _HTOOa
!o*oT}6n
import java.util.List; j:<E=[Kl
i]Kq
import org.apache.commons.logging.Log; [W^6=7EO
import org.apache.commons.logging.LogFactory; )j6S<mn
import org.flyware.util.page.Page; 5fVdtJk7
?:U6MjlQ"{
import com.adt.bo.Result; CZ]+B8Pl(x
import com.adt.service.UserService; /3Se*"u
import com.opensymphony.xwork.Action; B"+Ygvxb
Nkv2?o>l
/** A\4Gq
* @author Joa $#KSvo{otI
*/ y99G 3t
publicclass ListUser implementsAction{ dZnq 96<:|
N.&)22<m9
privatestaticfinal Log logger = LogFactory.getLog uX.Aq@j
{Ziq~{W_
(ListUser.class); X^aujK^@
T( ;BEyc?
private UserService userService; Oh8;YE-%
:U r%.0
private Page page; H2k>E}`
k U3]
eh\I
privateList users; xss D2*l
apw8wL2
/* -O(.J'=8
* (non-Javadoc) DK4V/>@8
* xhimRi
* @see com.opensymphony.xwork.Action#execute() F'SOl*v(s5
*/ 61gZZM
publicString execute()throwsException{ V]vk9M2q[l
Result result = userService.listUser(page); `^_.E:f
page = result.getPage(); 4AP<mo
users = result.getContent(); :=~([oSNW"
return SUCCESS; r-'j#|^tz
} R \`,Q'3
{BKI8vy
/** :j9;P7&"?
* @return Returns the page. [=LQ,e$r7
*/ mg#+%v
public Page getPage(){ 2RM0ca_F
return page; 2OK%eVba
} @8/-^Rh*
u 4)i7
/** -.z~u/uL
* @return Returns the users. V$:v~*Y9
*/ (a)d7y.oo
publicList getUsers(){ kyY tL_SD
return users; RYvS,hf6z
} 4;&(
8c~b7F
\
/** r--"JO%2
* @param page \&W~nYXq"
* The page to set. RJd55+h
*/ [kC-g @
publicvoid setPage(Page page){ y;Dw%m
this.page = page; (?J&Ar0
} FQ O6w'
53l9s<bOQ
/** jUjQ{eT
* @param users B-eYWt8s
* The users to set. 5ue{&z
@T
*/ 81aY*\
publicvoid setUsers(List users){ ^Z}INUv]7
this.users = users; iL5+Uf)E3
} seq
S*^7
*K0CUir|
/** [QL)6Xr
* @param userService %} \@Wk~
* The userService to set. \UN7lDH
*/ c()F%e:n
publicvoid setUserService(UserService userService){ r0S"}<8O
this.userService = userService; \mv7"TM
} GS)l{bS#[O
} ~0worI?
gbKms;:
^*Rr x
'MsxZqW"~
<4(rY9
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, 30F&FTW
V-I_SvWv\
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 w"A'uFXLc
5N '
QG<jE
么只需要: T_I"Tsv
java代码: SDJAk&Z}R
>Wy@J]Y#
IURi90Ir
<?xml version="1.0"?> =DF7l<&km
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork t;E-9`N
L!/USh:IP
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Yo:>m*31
uZW1
:cx
1.0.dtd"> H\)on"
Ym0Xl(Se
<xwork> 6K*7%8Y/G
tQUp1i{j\
<package name="user" extends="webwork- G~YV6??
HH[?LKd<
interceptors"> yjN|PqtSV
>mh:OJH45
<!-- The default interceptor stack name T`f9jD
7eh}Je8
--> AA yzT*^
<default-interceptor-ref UyIjM;X
%.<w8ag
name="myDefaultWebStack"/> aA0aW=R
VJJw"4DJ
<action name="listUser" V^.~m;ETu]
~M43#E[oOF
class="com.adt.action.user.ListUser"> G|X1c}zAL
<param spn1Ji
I[&z#foN=w
name="page.everyPage">10</param> l<^#@S H
<result .F}ZP0THnZ
3Jk;+<
name="success">/user/user_list.jsp</result> U2+CL)al^
</action> QbpRSdxy`$
m", $M>
</package> DhkzVp_
d<: VoQM6M
</xwork> {v~&.|
8ae]tX5$
q6/ o.j
}%_x T
?u 9)
GJO[
t</Kel|D
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 /koNcpJ
!L-.bve!
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。 (q3(bH~T)
f{5)yZ`J*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 N.BD]_C
i>0I '~V
U3%!#E{
r"J1C
j}S
我写的一个用于分页的类,用了泛型了,hoho I@ }:} 8t
Uj6R?E{Jt
java代码: lXL\e(ow
.ay
K+6I
^|as]x!sv
package com.intokr.util; sStaTR{
$eRxCX?b2
import java.util.List; =^=9z'u"=
y&9v0&o
/** +<@7x16
* 用于分页的类<br> %E~4 Ur
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 3(6i6 vV
* q^Oq:l$s
* @version 0.01 N$?mula
* @author cheng 7P:0XML}
*/ Yq<D(F#qx
public class Paginator<E> { -twIF49
privateint count = 0; // 总记录数 GVn7#0x
privateint p = 1; // 页编号 ,GZ(>|
privateint num = 20; // 每页的记录数 yq\)8Fe
privateList<E> results = null; // 结果 ~"brfjd|
hSr#/d w&
/** p;BdzV>
* 结果总数 4$d|}ajH
*/ d/Fjs0pt
publicint getCount(){ `;5UlkVZ5
return count; :3{@LOil^
} Og"50 -
ObMsncn
publicvoid setCount(int count){ 1wqCoDgkp
this.count = count; fy9{W @E3p
} NzNAhlXj3
xg\M9&J
/** S
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* 本结果所在的页码,从1开始 h'w9=Pk~6y
* 8~\Fpz|Og
* @return Returns the pageNo. qs 52)$
*/ rm(<?w%'?
publicint getP(){ `H^Nc\P#
return p; DQH _@-q
} hG&RGN_<6+
2%1g%
/** {HvR24#
* if(p<=0) p=1 Af
^6
* bo\|mvB~
* @param p W&BwBp]K
*/ BAg*zYV7
publicvoid setP(int p){ FbWkT4t|
if(p <= 0) |PDuvv!.f
p = 1; hFj.d]S
this.p = p; VH+^G)^) W
} *Rr,ii
!0 *=z~
/** =EsKFt"
* 每页记录数量 u|BD%5+J
*/ aSXoYG0\
publicint getNum(){ w*#TS8
\
return num; A{mbL2AxwC
} R b\=\
tN";o\!}
/** 2,q^O3F
* if(num<1) num=1 qPH]DabpI
*/ f![x7D$
publicvoid setNum(int num){ f(?>z!n0
if(num < 1) z`>a,X
num = 1; 9!gmS?f
this.num = num; wToz{!n
} -md2Z0^ Kc
W q F(
/** g4RkkoZ>)
* 获得总页数 |3Oe2qb
*/ QVn!60[lj
publicint getPageNum(){ ~=Er=
0
return(count - 1) / num + 1; {B?%r[nW
} 06 K8|K
4#;rv$
{
/** T!(I\wz;Bo
* 获得本页的开始编号,为 (p-1)*num+1 vlp]!7v
*/ PIB|&I|p
publicint getStart(){ V |#B=W
return(p - 1) * num + 1; Qaq{UW
} ;=*b:y Y
)8st
/** NT= ?@uxD
* @return Returns the results. ^ylJ_lN&=1
*/ CH`4FR.-
publicList<E> getResults(){ B~u{LvTE
return results; ElqHZ$a?
} 3f
eI
OtY.s\m y
public void setResults(List<E> results){ }1z=
C<
this.results = results; <)?H98S
} 7{8!IcR #
2s?j5 Sd
public String toString(){ {nm#aA%,
StringBuilder buff = new StringBuilder aE1h0`OT
yY[[)
(); nHNMoA
buff.append("{"); Ny\iRU)fN
buff.append("count:").append(count); ItC*[
buff.append(",p:").append(p); SO]x^+[
buff.append(",nump:").append(num); jWUN~#p!
buff.append(",results:").append u?Iop/b
dm)V \?b
(results); a%Mbq;
buff.append("}"); K34ca-~
return buff.toString(); ;# {XNq<1
} [WY
NA-O
_
nS';48
} =
fuF]yL%
7s<v06Wo
f!xIMIl)+