Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (nP 6Xq
+ -e8MvP
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]7WBoC8
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 e@k`C{{C]o
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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 gcImk0NIY
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。 +3VDapfin
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分页支持类: p%304oP6
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java代码: :SxOQ(n
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package com.javaeye.common.util; e2#"o{+@
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import java.util.List; LS:3Dtq
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publicclass PaginationSupport { UA4Q9<>~
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publicfinalstaticint PAGESIZE = 30; ?p{xt$<p
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privateint pageSize = PAGESIZE; &fBLPF% 6
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privateList items; !O$ */7
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privateint totalCount; #8;|_RU
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privateint[] indexes = newint[0]; s{q)m@
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privateint startIndex = 0; *[*E|by
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public PaginationSupport(List items, int hq9b
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totalCount){ y:!MWZ
setPageSize(PAGESIZE); =YX/]g|9K
setTotalCount(totalCount); ]ABpOrg
setItems(items); ]Jj\**
setStartIndex(0); 9H*$3
} &fYx0JT
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public PaginationSupport(List items, int _>HXQ6Hw
UTQ$sg|7p
totalCount, int startIndex){ TX{DZ#
setPageSize(PAGESIZE); }~lF Rf
setTotalCount(totalCount); ]B>Y
+
setItems(items); b?-%Uzp<
setStartIndex(startIndex); 5YIiO7@4
} +MC>?rr_u
K5(?6hr;
public PaginationSupport(List items, int e,Xvt5
*iF>}yh e
totalCount, int pageSize, int startIndex){ W|=?-
setPageSize(pageSize); 7Z>u|L($m
setTotalCount(totalCount); ,=lMtW
setItems(items); ^DHFP-G?e
setStartIndex(startIndex); L>{E8qv>w
} p}.P^`~j
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publicList getItems(){ ?8Cxt|o>
return items; )rD] y2^<
} !@-j!Ub
!B?/6XRUx
publicvoid setItems(List items){ NFGC.<
this.items = items; P]2M
} 1?HUXN#,
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publicint getPageSize(){ } oJ+2OepN
return pageSize; ?mY )m
+
} zdn e2
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publicvoid setPageSize(int pageSize){ /s6':~4
this.pageSize = pageSize; </<_e0
} wd*i~A3+?
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publicint getTotalCount(){ oUZwZ_yKW
return totalCount; 7"=
} ,oDZ:";
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publicvoid setTotalCount(int totalCount){ }Evy fc#D
if(totalCount > 0){ fl~k')s
this.totalCount = totalCount; V~5vVY_HG&
int count = totalCount / #e&j]Q$Eh
/woa[7Xe
pageSize; +IVVsVp
if(totalCount % pageSize > 0) p<'mc|hGq
count++; Z!6\KV]
indexes = newint[count]; tjOfekU
for(int i = 0; i < count; i++){ 8_f0P8R!y
indexes = pageSize * mT@UQCG
pw:<a2.
i; yyk[oH-Q
} (|ga#%iI
}else{ PiI ):B>
this.totalCount = 0; }K;@$B6,@
} F=B>0Q5
} L3nHvKA]
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publicint[] getIndexes(){ xpFu$2T6P.
return indexes; e }/c`7M
} UuT>qWxQ8
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publicvoid setIndexes(int[] indexes){ 3Q[]lFJ}F
this.indexes = indexes; M O* m@
} s;}';#
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publicint getStartIndex(){ \ ;Hj,z\
return startIndex; >?M:oUVDU
} 60~{sk~E
6,_CL M
publicvoid setStartIndex(int startIndex){ ekI1j%fO
if(totalCount <= 0) ` ]WU=Ss
this.startIndex = 0; (0D0G-r:
elseif(startIndex >= totalCount) *|$s0ga C
this.startIndex = indexes F#4?@W
tK{`?NS
[indexes.length - 1]; zo@>~G3$9
elseif(startIndex < 0) AyNl,Xyc4
this.startIndex = 0; &[I#5bGk
else{ \EYhAx`2
this.startIndex = indexes ~,R_
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[startIndex / pageSize]; 3X0^xUA6
} * _C6.%{
} lqqY5l6j
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publicint getNextIndex(){ D8`,PXtV
int nextIndex = getStartIndex() + zfi{SO
l
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pageSize; ~ ;)@a
if(nextIndex >= totalCount) sPkT>q
return getStartIndex(); ,2H5CFX/
else OD>-^W t;%
return nextIndex; ; {I{X}b
} rVQ:7\=Z
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publicint getPreviousIndex(){ _}jj>+zA`
int previousIndex = getStartIndex() - W@"M/<r@/
yuFuYo&[?v
pageSize; ?ZlwRjB\
if(previousIndex < 0) mg'-]>$ $]
return0; 3zWY%(8t4?
else K+T`'J4
return previousIndex; LdWeI
} /;HytFP
w'M0Rd]
} aH"tSgi
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抽象业务类 F\-qXSA
java代码: ^N Et{]x
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/** X:8=jHkz
* Created on 2005-7-12 J_rCo4}
*/ UfcM2OmbK
package com.javaeye.common.business; * +A!12s@
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import java.io.Serializable; = \X<UA}
import java.util.List; oH6(Lq'q
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import org.hibernate.Criteria; lt,x(2
import org.hibernate.HibernateException; s)/i_Oe$\
import org.hibernate.Session; &lI.N~Ao
import org.hibernate.criterion.DetachedCriteria; n)`*{uv$
import org.hibernate.criterion.Projections; +/Y)s5@<
import zb9d{e
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org.springframework.orm.hibernate3.HibernateCallback; n=rPFpRLF
import *%Gy-5hM
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org.springframework.orm.hibernate3.support.HibernateDaoS )E6m}? H5
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upport; Mqw&%dz'_
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import com.javaeye.common.util.PaginationSupport; 9=3V}]^M
dhm;
public abstract class AbstractManager extends A
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HibernateDaoSupport { NSHlo*)}
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privateboolean cacheQueries = false; ) 3YE$,
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privateString queryCacheRegion; q%>L/KJ#
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publicvoid setCacheQueries(boolean 4,$x~m`N
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cacheQueries){ b.Y[:R_9&
this.cacheQueries = cacheQueries; =9pFb!KX
} ;PS[VdV
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publicvoid setQueryCacheRegion(String .6vQWt7@
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queryCacheRegion){ mGL%<4R,
this.queryCacheRegion = 00b
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queryCacheRegion; 9^
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} u{>5
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publicvoid save(finalObject entity){ ?]3`WJOj
getHibernateTemplate().save(entity); I"@5=m5
} fWKv3S1dT
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publicvoid persist(finalObject entity){ .`)ICX
getHibernateTemplate().save(entity); ||L qx#e=
} y\x!Be;6Z.
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publicvoid update(finalObject entity){ 5,?9#n\E,
getHibernateTemplate().update(entity); .4-;
} _|6{(
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publicvoid delete(finalObject entity){ )C|>M'g@v
getHibernateTemplate().delete(entity); evszfCH'J
} QKOo
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publicObject load(finalClass entity, lZ_i~;u4@v
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finalSerializable id){ 9 .%{M#j
return getHibernateTemplate().load X.T.^}=
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(entity, id); vZXyc*
} y@_4OkR@
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publicObject get(finalClass entity, i 3?zYaT
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finalSerializable id){ C@Wm+E~;8
return getHibernateTemplate().get Q>Q$BCD5
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(entity, id); .[O*bk
} T+2?u.{I
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publicList findAll(finalClass entity){ *5|\if\
return getHibernateTemplate().find("from #Va@4<4r
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" + entity.getName()); @+xkd(RfN
} WVwNjQ2PM
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publicList findByNamedQuery(finalString EW]gG@w]5r
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namedQuery){ Q) FL|
return getHibernateTemplate [#2= w
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().findByNamedQuery(namedQuery); /- kMzL
} gQ/zk3?k
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publicList findByNamedQuery(finalString query, fNB*o={r|
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finalObject parameter){ yl3iU:+V
return getHibernateTemplate t0?BU~f
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().findByNamedQuery(query, parameter); yY,.GzIjCj
} YjG0: 9
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publicList findByNamedQuery(finalString query, $9ON3>
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finalObject[] parameters){
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return getHibernateTemplate jkPXkysm
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().findByNamedQuery(query, parameters); q:nYUW o
} Vr5a:u'
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publicList find(finalString query){ 1>|p1YZ"
return getHibernateTemplate().find 8vaqj/
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(query); \ &_
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} >#>YoA@S
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publicList find(finalString query, finalObject :l*wf/&z
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parameter){ (>)Y0ki}
return getHibernateTemplate().find f Z \Ev%F
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(query, parameter); ];Z_S`JR
} N8mK^{
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public PaginationSupport findPageByCriteria I98wMV8
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(final DetachedCriteria detachedCriteria){ zHx?-Q&3
return findPageByCriteria Bpqq-_@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); S9xC> |<
} 1uD}V7_y"
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public PaginationSupport findPageByCriteria Uvz9x"0[u
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(final DetachedCriteria detachedCriteria, finalint FiFZM
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startIndex){ E2dSOZS:)%
return findPageByCriteria i&?~QQP`
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(detachedCriteria, PaginationSupport.PAGESIZE, &f!!UZMt)
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startIndex); ~%sDQt\S
} OGae]O<
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public PaginationSupport findPageByCriteria T>LtN
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(final DetachedCriteria detachedCriteria, finalint -|ee=BV
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pageSize, tU?lfU[7
finalint startIndex){ ,,,5pCi\
return(PaginationSupport) 3EzI~Zsx
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getHibernateTemplate().execute(new HibernateCallback(){ VoP(!.Ua>7
publicObject doInHibernate ,rTR
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(Session session)throws HibernateException { {qh`8
Criteria criteria = LfK <%(:
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detachedCriteria.getExecutableCriteria(session); tb_}w@:kU
int totalCount = 6%:'2;xM
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((Integer) criteria.setProjection(Projections.rowCount u/hD9g~H7K
AoTL)',
()).uniqueResult()).intValue(); O-: ~6A
criteria.setProjection /S|Pq!4<
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(null); eBBh/=Zc
List items = lYq
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g
criteria.setFirstResult(startIndex).setMaxResults BeplS
1L^\TC
(pageSize).list(); <hS >L1ZSr
PaginationSupport ps = qt3\*U7x
3
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new PaginationSupport(items, totalCount, pageSize, m~X:KwK4
\N;s@j W
startIndex); TrHBbyqk
return ps; PRf2@0ZV
} \d
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}, true); 4?d2#Xhs8
} G =lC[i
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public List findAllByCriteria(final (\SxG\`
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DetachedCriteria detachedCriteria){ |ukEnjI`u
return(List) getHibernateTemplate )8P<ZtEU
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().execute(new HibernateCallback(){ od-N7lp#
publicObject doInHibernate ~sk 4v:-
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(Session session)throws HibernateException { <tFq6|
Criteria criteria = A"w
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q
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detachedCriteria.getExecutableCriteria(session); Hh;7 hY\
return criteria.list(); CQ13fu+|6
} u,/PJg-(!
}, true); Q%KS$nP9
}
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public int getCountByCriteria(final :@kSDy+*Q
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DetachedCriteria detachedCriteria){ NlWIb2,
Integer count = (Integer) \}G/F!
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getHibernateTemplate().execute(new HibernateCallback(){ o3%Gc/6%
publicObject doInHibernate ^bS&[+9E
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(Session session)throws HibernateException { _%"/I96'
Criteria criteria = l$.C40v
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detachedCriteria.getExecutableCriteria(session); @YV-8;hO
return 7FfzMs[\e
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criteria.setProjection(Projections.rowCount =[vT=sHz7
Q- j+#NGc
()).uniqueResult(); -,}f6*
} +ZXk0sP_<
}, true); VxaJ[s3PQ&
return count.intValue(); kM@8RAxA
} 6(X(f;MEl
} oGXT,38*
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用户在web层构造查询条件detachedCriteria,和可选的 FRX'"gIR0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _f2(vWCW;J
Smg,1,=
PaginationSupport的实例ps。 q=g;TAXZl
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ps.getItems()得到已分页好的结果集 XG_lyx%:E
ps.getIndexes()得到分页索引的数组 sIg{a(1/
ps.getTotalCount()得到总结果数 bi[vs|
ps.getStartIndex()当前分页索引 JZ80 |-c
ps.getNextIndex()下一页索引 *G2p;n=2
ps.getPreviousIndex()上一页索引 &5c)qap;n
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zTm&m#){3A
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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 s#-`,jqD
57D /"
一下代码重构了。 %A:<rO85o
M~p=OM<
我把原本我的做法也提供出来供大家讨论吧: +-K-CXt
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首先,为了实现分页查询,我封装了一个Page类: oTT/;~ I
java代码: S'vrO}yU
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/*Created on 2005-4-14*/ 7s1FJm=Y/
package org.flyware.util.page; )t&j0`Yq
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/** R\
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* @author Joa ~ex1,J*}t
* E0Ig/
j
*/ {3@/@jO?
publicclass Page { Gpo(Zf?
$hn#T#J3
/** imply if the page has previous page */ 4*G#fW-
privateboolean hasPrePage; ebp18_a|
ixp(^>ZN
/** imply if the page has next page */ YN.rj-;^+
privateboolean hasNextPage; L+(5`Y
Vw<=& w #K
/** the number of every page */ 9<G-uF
privateint everyPage; &0+;E-_
k7'B5zVd
/** the total page number */ ;| )&aTdH
privateint totalPage; M')f,5i&$
rp{q.fy'U
/** the number of current page */ K!0vvP2H
privateint currentPage; I?EtU/AD
Pur~Rz\\
/** the begin index of the records by the current OZB(4{vnyC
)zf&`T
query */ h/mmV:v
privateint beginIndex; [;
( Y'q%$
`XE8[XY
/** The default constructor */ V80g+)|
public Page(){ :Bz*vH
~K&ko8
} iYEhrb
-}AAA*P
/** construct the page by everyPage U4w^eWzP
* @param everyPage wG ua"@IE
* */ 4w<U%57
public Page(int everyPage){ f]jAa?d T&
this.everyPage = everyPage; 6X$]d^)h{
} Oc}4`?oy<O
h2QoBGL5
/** The whole constructor */ @6~r7/WD
public Page(boolean hasPrePage, boolean hasNextPage, +Vl\lL
-
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Cd?aC
int everyPage, int totalPage, >WVos 4
int currentPage, int beginIndex){ 9o@5:.b<j
this.hasPrePage = hasPrePage; lc?9B
this.hasNextPage = hasNextPage; {U=Mfo?AH
this.everyPage = everyPage; b MZ-{<+i
this.totalPage = totalPage; >TK:&V
this.currentPage = currentPage; \Z{6j&;
this.beginIndex = beginIndex; \vjIw{
} iO4Yfj#?
z/dpnGX
/** (P%{Tab
* @return 7k.=_Tl
* Returns the beginIndex. @eU;oRVc{
*/ =]X_wA;%
publicint getBeginIndex(){ ]|KOc& y:I
return beginIndex; $ @QF<?i~
} ue"?n2
6q-X$
/** o
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* @param beginIndex 4! ]28[2B6
* The beginIndex to set. ixm-wZI
*/ }TI"j{(QJ
publicvoid setBeginIndex(int beginIndex){ 7:awUoV8f
this.beginIndex = beginIndex;
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%
} U$-Gc[=|
OHTJQ5%zL
/** JVy- Y
* @return ~\B1\ G
* Returns the currentPage. DyhW_PH2J
*/ Tk\?$n
publicint getCurrentPage(){ t@m!k+0
return currentPage; BC.~wNz6
} r{R879
n] {sBI3
/** sl?> X)}
* @param currentPage b9`vYnLk
* The currentPage to set. j
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*/ &m<:&h& b
publicvoid setCurrentPage(int currentPage){ di$\\ Ah
this.currentPage = currentPage; HG
kL6o=
} S<fSoU+RJ
36iDiT_
/** >d2U=Yk!
* @return hq+j8w}<-
* Returns the everyPage. Esx"nex
*/ ^k{b8-)W<
publicint getEveryPage(){ r Z)?uqa
return everyPage; \zOo[/-<
} ~gZ"8frl
($s%5|
/** noI>Fw<V
* @param everyPage 'y_<O |-
* The everyPage to set. s9^r[l@W0U
*/ Ix~_.&
publicvoid setEveryPage(int everyPage){ Lh`B5
this.everyPage = everyPage; \MhSIlM#
} ,,
S]_S
^phgNzD
/** qrdA4S
* @return my|]:(_0d
* Returns the hasNextPage. DD$YMM
*/ F{,<6/ayRz
publicboolean getHasNextPage(){ E^'f'\m
return hasNextPage; y(81| c#
} b~oQhU??"
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/** ^/c v8M=
* @param hasNextPage aUZh_<@
* The hasNextPage to set. Sr Vo0$5)
*/ =*2_B~`
publicvoid setHasNextPage(boolean hasNextPage){ +hiskV@ v
this.hasNextPage = hasNextPage; g_8A1lt
} zH)M,+P
vU(uu:U9
/** 5ub|r0&M
* @return o,(]w kF
* Returns the hasPrePage. cl,\N\
*/ +q<G%PwbV
publicboolean getHasPrePage(){ E]@$,)nC
return hasPrePage; )O}q{4,}
} ,76xa%k(U|
L'A9TW2
/** }Zuk}Og9+
* @param hasPrePage {~*^jS']5
* The hasPrePage to set. Ij w{g%
*/ VAD9mS^~
publicvoid setHasPrePage(boolean hasPrePage){ |!Ryl}Oi
this.hasPrePage = hasPrePage; Hs6?4cgj
} vIzREu|5
esh7*,7-z*
/** gPT<%F
* @return Returns the totalPage. 'DeI]IeP
* 'GyO
*/ qz_'v{uAj
publicint getTotalPage(){ _dQg5CmlG
return totalPage; sd
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} !v fbgK
THN//}d
/** [uLwr$N<%L
* @param totalPage NP#6'eH\
* The totalPage to set. Q%T[&A}3B
*/ #OMFv.
publicvoid setTotalPage(int totalPage){ F9}j iCom
this.totalPage = totalPage; `W=3_
} vw
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} 6,~Y(#
MrU0Jrk4+
VY1&YR}Y
,h<xL-
kN~:Bh$
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 d}:eLC
<6rc8jYz
个PageUtil,负责对Page对象进行构造: [aS<u`/g|
java代码: I5%#A/|z
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/*Created on 2005-4-14*/ zhdS6Gk+
package org.flyware.util.page; D\H;_k8
rWMG6+Scb
import org.apache.commons.logging.Log; % S vfY {
import org.apache.commons.logging.LogFactory; uyqu n@q
(&osR|/Tq
/** zBjtPtiiI8
* @author Joa 7{JIHY+
* >}7Ml
*/ 'qy
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publicclass PageUtil { t@vVE{`
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privatestaticfinal Log logger = LogFactory.getLog h<0&|s*a)
l^k/Y
]
(PageUtil.class); iwVsq_[]L
FL|\D
/** MW|*Z{6*
* Use the origin page to create a new page BB9+d"Sq
* @param page :3N&&]
* @param totalRecords p!Xn iY
* @return QWQJSz5
*/ umo<9Y
publicstatic Page createPage(Page page, int eYQPK?jo
*ufVZzP(
totalRecords){ [C^&iLX/F*
return createPage(page.getEveryPage(), ^ h?]$P
*,FU*zi
page.getCurrentPage(), totalRecords); wl.a|~-
} PP-U.
^&Vj m
/** FGey%:p9$
* the basic page utils not including exception <y2HzBC
+5i~}Q!
handler q@=3`yQ
* @param everyPage 7.y35y
* @param currentPage mDdL7I
* @param totalRecords LX8A@Yct
* @return page 259R5X<V
*/ +ktubJ@Qgj
publicstatic Page createPage(int everyPage, int IzI2w6a
)R^&u`k
currentPage, int totalRecords){ nh'TyUd!
everyPage = getEveryPage(everyPage); \=&F\EV
currentPage = getCurrentPage(currentPage); M/a40uK
int beginIndex = getBeginIndex(everyPage, 6* 6 |R93
%M5{-pJ|C
currentPage); aN?^vW<
int totalPage = getTotalPage(everyPage, ?RPVd8PUhN
=1r!'<"h
totalRecords); +4g H=6
boolean hasNextPage = hasNextPage(currentPage,
NIh?2w"\
S
Rb-eDk'
totalPage); 5q,ZH6\
{
boolean hasPrePage = hasPrePage(currentPage); s1>d)2lX
"&%Lhyt
returnnew Page(hasPrePage, hasNextPage, 7U1^=Y@t}
everyPage, totalPage, H8!)zZ
currentPage, Q+7+||RW
z]/!4+
beginIndex); .LI(2lP
} N8KH.P+
-{z<+(K!$
privatestaticint getEveryPage(int everyPage){ 92(P~Sdv
return everyPage == 0 ? 10 : everyPage; n@$("p
} 6PyW(i(bs
)#l&BV5
privatestaticint getCurrentPage(int currentPage){ Ay@/{RZz
return currentPage == 0 ? 1 : currentPage; @%"r69\
} lj /IN[U/
QAzwNXE+
privatestaticint getBeginIndex(int everyPage, int POI|#[-V
q:MSV{k
currentPage){ :|%1i>O
return(currentPage - 1) * everyPage; GS&I6
} -2B3 xIZJ
_$KEE|9
privatestaticint getTotalPage(int everyPage, int ,4HZ-|EOZ
puAjAvIax
totalRecords){ Oq*;GR(Q
int totalPage = 0; Oy_%U*
| Di7,$c
if(totalRecords % everyPage == 0) y>>)Yo&|
totalPage = totalRecords / everyPage; 7{lWg x
else : "^/?Sd
totalPage = totalRecords / everyPage + 1 ; B|K^:LUk9
Mx Dqp;
return totalPage; : G'a"%x
} xzXNcQ
zJ30ZY:
privatestaticboolean hasPrePage(int currentPage){ 4MrUo9L$s
return currentPage == 1 ? false : true; |Ae7wXOs
} m.68ctaa
4Opf[3]
privatestaticboolean hasNextPage(int currentPage, \0n<6^y
watTV\b
int totalPage){ BA8g[TA7K
return currentPage == totalPage || totalPage == 3b?8<*
ye-[l7
0 ? false : true; `ES+$ O>
} M#k$[w}=
xW|8-q
4\E1M[ 6
} u'T?e+=
4_-L1WH
/?NfU.+K
RiZ)#0
22/"0=2g
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 c_T+T/O
UPy 4ST
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 K'f^=bcI
'cqY-64CJZ
做法如下: SLz;5%CPV
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o@L2c3?c5
hkOFPt&
的信息,和一个结果集List: y3':x[d
java代码: _jb&=f8
^^g u
4Uhh]/
/*Created on 2005-6-13*/ h_Ssm{C\
package com.adt.bo; 2UG>(R:
mNlbiB
import java.util.List; TBZhL
3hVuC1;"
import org.flyware.util.page.Page; CfT(a!;Eox
0oe2X1.%
/** j;I(w [@P
* @author Joa fohZ&f|>
*/ DzIV5FG
publicclass Result { 1)3'Y2N*
Wuk!\<T{
private Page page; E`Br# "/Bl
.kTOG'K\e
private List content; ;ojJXH~$}
8)>4ZNXz
/** ;9<?~S
* The default constructor y;%\w-.\
*/ <'4 8mip
public Result(){ MDZPp;\)
super(); 6~l+wu<$
} -p"}K~lt:
NiMsAI@j
/** kQp*+ras
* The constructor using fields )NK#}c~5
* =y >CO:^G%
* @param page \Xe{vlo>h
* @param content r$<M*z5q(\
*/ G#~U\QlG-
public Result(Page page, List content){ yg4#,4---b
this.page = page; 1\)C;c,
this.content = content; C~WWuju'
} A-, hm=?
=b8u8*ua
/** B.!&z-)#
* @return Returns the content. h8 FV2"
*/ 1p$ *N
publicList getContent(){ /l+"aKW
2
return content; `.Zm}'
} lavy?tFer
$1FnjL5u
/** BC5R$W.e
* @return Returns the page. q VavP6I
*/ "YAnGGx)LZ
public Page getPage(){ &?TXsxf1Zh
return page; do9~#F
} "Th;YJu
m.<or?l'y>
/** j{johV+`8
* @param content %<r}V<OeR
* The content to set. F&lH5
*/ @NL37C
public void setContent(List content){ 1!yd(p=cL
this.content = content; xLms|jS
} Xpv<v[a
-zWNQp$
/** $$SJLV
* @param page C$$Zwgy
* The page to set. RR|X4h0.
*/ VrWQ] L
publicvoid setPage(Page page){ QpA$='
this.page = page; #R7hk5/8n}
} "Pu917_P
} ?]aVRmL
8hYl73#
?2R!n"m-d
76]Z~^Y
^=a:{["@!
2. 编写业务逻辑接口,并实现它(UserManager, A-d<[@d0
Z78i7k }
UserManagerImpl) Sy]W4%
java代码: wn|;Li
H/k]u)Gtv
Y]^*mc0fE
/*Created on 2005-7-15*/ eA{A3.f"Hz
package com.adt.service; 72/ bC
-8vGvI>
import net.sf.hibernate.HibernateException; Y;iI=U
]
_W'-B
import org.flyware.util.page.Page; B.KK@
CEBu[TT/9
import com.adt.bo.Result; ]1eZ<le`6
hTWZIW@
/** auqN8_+=
* @author Joa \t`Vq JLyu
*/ I8 [
*
publicinterface UserManager { DC8\v+K
!&cfX/y8
public Result listUser(Page page)throws [k75+#'
=M9R~J!
HibernateException; 0l/7JH_@V
?* r
} .tHjGx
`z.sWF|f!O
>DbG
)0|
2^"!p;WQ
kw} E0uY
java代码: j+S&5C/{
*M$mAy<
^hr# 1
/*Created on 2005-7-15*/ Ui-Y`
package com.adt.service.impl; 4=`1C-v?q
X$G:3uoN
import java.util.List; r\}?HS06
etUfdZ
import net.sf.hibernate.HibernateException; TXT<6(
ic3Szd^4
import org.flyware.util.page.Page; 2}bXX'Y
import org.flyware.util.page.PageUtil; w`r%_o-I
g/WDAO?d
import com.adt.bo.Result; ZoYllk
import com.adt.dao.UserDAO; w~+\Mf z
import com.adt.exception.ObjectNotFoundException; Jr%F#/
import com.adt.service.UserManager; 8N$Xq\Da+>
d>T8V(Bb
/** /;:4$2R(;
* @author Joa J_j4Zb% K
*/ >e(@!\ x
publicclass UserManagerImpl implements UserManager { 7]Hf3]e>/
LNrM`3%2-
private UserDAO userDAO; |`kkmq
;8f)p9vE
/** ("{vbs$;
* @param userDAO The userDAO to set. XD?]+
*/ s<Nw)Ynw
publicvoid setUserDAO(UserDAO userDAO){ N H:Bdl3
this.userDAO = userDAO; 8|$g"?CU
} 9~2iA,xs
@HnahD
/* (non-Javadoc) osmCwM4O
* @see com.adt.service.UserManager#listUser '66nqJb*
QFN 9j
(org.flyware.util.page.Page) M?;YpaSe+
*/ ;49sou
public Result listUser(Page page)throws m6H+4@Z-;(
#Ye0*`
HibernateException, ObjectNotFoundException { p&0 G
int totalRecords = userDAO.getUserCount(); .wTb/x
if(totalRecords == 0) ;Xqi;EA
throw new ObjectNotFoundException `Fe/=]<$
bD3 dT>(+
("userNotExist"); K6)IBV;
page = PageUtil.createPage(page, totalRecords); I>w|80%%
List users = userDAO.getUserByPage(page); 'vZy-qHrV
returnnew Result(page, users); 9eE
FX7
} ;PqC*iz
?5;wPDsK
} jsF5q~F
ME$J?3r
TEGg)\+D>
Im};wJ&
(lq%4h
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 j~=<O<P
Jk:ZO|'Z
询,接下来编写UserDAO的代码: ()$m9%x
3. UserDAO 和 UserDAOImpl: [9}<N2,9z
java代码: ,J<+Wxz
w@YPG{"j
3h%Nd&_9
/*Created on 2005-7-15*/ /QCg E~
package com.adt.dao; aI}htb{m`
FPZ@6
import java.util.List; @at*E%T[
"(~fl<;
import org.flyware.util.page.Page; OwgPgrV
!\$4A,
import net.sf.hibernate.HibernateException; EFu$>Z4
G9#3
|B-?
/** vXSA_"0t
* @author Joa QW_v\GHx
*/ 2#CN:b]+
publicinterface UserDAO extends BaseDAO { s0h0EpED
Sht3\cJ8
publicList getUserByName(String name)throws G=CP17&h6
m(5LXHJnv
HibernateException; MCIuP`sC|
sYSq >M
publicint getUserCount()throws HibernateException; gdh|X[d
Cv&>:k0V
publicList getUserByPage(Page page)throws 9KT85t1#
)(1tDQ`L>
HibernateException; /?|;f2tbV2
vS:=%@c>ta
} R!\._m?\h
kFT*So`'
Gg:W%
EpCNp FQT<
$bBUL C
java代码: CG J_k?h
sebuuL.l0<
j xq89x
/*Created on 2005-7-15*/ P8w56
package com.adt.dao.impl; jH;L7
8u"C7} N_
import java.util.List; x
#|t#N%
JuRWR0@`
import org.flyware.util.page.Page; An,TunX
.Rb1%1bdc
import net.sf.hibernate.HibernateException; N>g6KgX{K
import net.sf.hibernate.Query; ;qUd]c9oi
0&Iu+hv
import com.adt.dao.UserDAO; ~X'hRNFx~
X*bOE}
/** i\4d d)p-
* @author Joa :Fh _Ya0
*/ DIhV;[\
public class UserDAOImpl extends BaseDAOHibernateImpl QYAt)Ik9q
3L4v@
implements UserDAO { U9%^gC
>=1UhHFNI
/* (non-Javadoc) Q(Pc
* @see com.adt.dao.UserDAO#getUserByName mVK^gJ3
m
(kKUv
(java.lang.String) ?8<R)hJa<
*/ B7%m7GM
publicList getUserByName(String name)throws /CbM-jf
Cs,t:ajP
HibernateException { ,ob)6P^rw
String querySentence = "FROM user in class Q%V530
P;
m8gU8a"(
com.adt.po.User WHERE user.name=:name"; O"RIY3m
Query query = getSession().createQuery /$FpceB!W
"Gq%^^*
(querySentence); :&RpB^]
query.setParameter("name", name); I Vw'YtZ
return query.list(); wc}4:~
} <c
[X^8
k4"O}jQO
/* (non-Javadoc) FuFICF7+C
* @see com.adt.dao.UserDAO#getUserCount() w (ev=)7<
*/ @ "CP@^
publicint getUserCount()throws HibernateException { _Pl5?5eZj
int count = 0; M=EV^Tw-=
String querySentence = "SELECT count(*) FROM Of<Vr.m{R
A2`Xh#o
user in class com.adt.po.User"; <bywi2]z
Query query = getSession().createQuery -t125)6 I
99b"WH^3$y
(querySentence); Bv6~!p
count = ((Integer)query.iterate().next """eU,"
E1qf N>0Z
()).intValue(); ~(^?M
return count; VlxHZ
} edlsS}8^
UGA``;f
/* (non-Javadoc) i/,IG+4vI
* @see com.adt.dao.UserDAO#getUserByPage bHzH0v]:
cNl$
vP83z
(org.flyware.util.page.Page) x!?$y_t
*/ 0j' Xi_uM
publicList getUserByPage(Page page)throws E/>kvs%
5d)\Z0s
HibernateException {
`EVy
String querySentence = "FROM user in class l?x'R("{
L@G~9{U>
com.adt.po.User"; M,DwBEF?
Query query = getSession().createQuery 4z qO!nk
u#$sO;8s
(querySentence); "z{rC}
query.setFirstResult(page.getBeginIndex()) KU.F4I8}q
.setMaxResults(page.getEveryPage()); w?R#ly
return query.list(); aR%E"P-6l
} QY1|:(
"^VPe[lA
} (;++a9GK
^'hh?mL
}>'1Qg
E*}1_,q)
l9{.~]V
至此,一个完整的分页程序完成。前台的只需要调用 |v h{Kb@
;n/04z
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ve[&_(fP
6>Is-/hsy
的综合体,而传入的参数page对象则可以由前台传入,如果用 9aY}+hgb#
mGc i>)2
webwork,甚至可以直接在配置文件中指定。 f;,^
]mw
tE:6
下面给出一个webwork调用示例: "!PN +gB
java代码: m Wh
aByd,uSe)_
9Pdol!
/*Created on 2005-6-17*/ ;0O>$|kg
package com.adt.action.user; nSbcq>3
_Xfn
import java.util.List; h09fU5l
S&Sa~Oq<o
import org.apache.commons.logging.Log; 0JV|wd8j
import org.apache.commons.logging.LogFactory; ,4S6F HK
import org.flyware.util.page.Page; OZ Hfd7K4A
p</V_BIW
import com.adt.bo.Result; ;PWx#v+vwF
import com.adt.service.UserService; 1&utf0TX6q
import com.opensymphony.xwork.Action; OUtMel_
~s)
`y2Y
/** <USr$
* @author Joa p4wx&VLi
*/ Q;2n
publicclass ListUser implementsAction{ |@pn=wW
[^\HP]*Q{
privatestaticfinal Log logger = LogFactory.getLog _4X3g%nXl
I8
(ListUser.class); !u=A9i!
ac/<N%
private UserService userService; 4+B
OS ~
^ZDpG2(zk
private Page page; QlH,-]N$L
xdrs!GV:
privateList users; KqzQLu
T7ICXpe@
/* hixG/%aO
* (non-Javadoc) f9?f!k
* =(p]L
* @see com.opensymphony.xwork.Action#execute() ?0'db
*/ )L$)qfQ~x
publicString execute()throwsException{ >~rytg] f
Result result = userService.listUser(page); 80Z'1'u0
page = result.getPage(); rLI);!^-
users = result.getContent(); }+GIrEDId
return SUCCESS; n]v,cfn/=<
} I_iXu;UX
xC -&<s
/** _{y4N0
* @return Returns the page. "Rr650w[
*/ 'EkuCL
public Page getPage(){ >1NE6T
return page; :lp
V
} p!H'JNG
3mLtnRX[m
/** ]}>uvl^l
* @return Returns the users. {7LNQGiJ
*/ :Wd@Qy?;
publicList getUsers(){ rFG_CC2
return users; <g{d>j
} ;hJz'&UWQ
asKAHVT(
/** nlR7V.
* @param page NrWgaPO)i
* The page to set. #;F*rJ[XY
*/ )o_Pnq9_
publicvoid setPage(Page page){ 1'BC
R
this.page = page; `z?h=&N
} 6w4}4i
[F}_Ime
/** [IPXU9&Q
* @param users Ae_:Kc6
* The users to set. Xx
e07J~
*/
3 cF4xUIZ
publicvoid setUsers(List users){ !A&>Eeai
this.users = users; m"RSDM!
} !6l}s$1i|
P,={ C6*
/** ja+PVf
* @param userService ]r(s02
* The userService to set. aW;DfH
*/ L_Lhmtm}m
publicvoid setUserService(UserService userService){ @agxu-Y
this.userService = userService; KU*XRZu)
} 9;`E,w
} <@J0
770
HCZVvsG
G)3Q|Vc
Wr;9Mz&{
-5d^n\CDK
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, }^zsN`
tu5T^"BqO
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 0^>b=a
Ula
h!s
么只需要: W9/HM !
java代码: !]t5(g_
`xF^9;5mi
=.ReM_.
<?xml version="1.0"?> X}_Gk5q*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #-8%g{
pra0:oHN
1.0//EN" "http://www.opensymphony.com/xwork/xwork- o&:'MwU
{Xv0=P
1.0.dtd"> cE+Y#jB
IT:8k5(L5j
<xwork> r!y3VmJ'm
u{%dm5
<package name="user" extends="webwork- BY`vs+]XY
Fb\ E39
interceptors"> :'X:cL
(e_ l1O?
<!-- The default interceptor stack name ^!*nhs%
kB-]SD#
--> .0?A0D?sP
<default-interceptor-ref {B7${AE
K7=>o*p
name="myDefaultWebStack"/> ~+CEek
fRomP-S
<action name="listUser" bO+]1nZ.
<KBS ;t="1
class="com.adt.action.user.ListUser"> i 2l/y,UX
<param ;2[o>73F
\/F*JPhy
name="page.everyPage">10</param> XWag+K
<result L*(`ccU
e&-MP;kgW9
name="success">/user/user_list.jsp</result> Fuy"JmeR
</action> $nr=4'yZ
BI+x6S>d
</package> P`AW8Y6o
=2e{T J/
</xwork> ~'w]%rh!
fxknfgbg
Q)2i{\GPVn
=buarxk
#MUY!
#T++5G
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 K8RV=3MBLD
l-$5CO
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 U<I]_]
U88gJ[$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3@wio[
l4*vM
*=X61`0
1'f&
xq&r|el
我写的一个用于分页的类,用了泛型了,hoho rUh2[z8:
@K\hgaQ
java代码: W<>R;~)
W0XfU`
QzS=oiL
package com.intokr.util; mjKu\7F
$;Z0CG
import java.util.List; .~X&BY>qP
KW(^-:wmr
/** .S*VYt%K7
* 用于分页的类<br> <FfmDR
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0( q:K6zI}
* )3.=)?XW
* @version 0.01 |cgc^S/~H
* @author cheng {$Z
S
27
*/ Tly*i"[&
public class Paginator<E> { DO6
p v
privateint count = 0; // 总记录数 17#t 7Yk
privateint p = 1; // 页编号 VI]~uTV
privateint num = 20; // 每页的记录数 V-dyeb
privateList<E> results = null; // 结果
_6-N+FI
c!N#nt_<
/** 7n]ukqZ
* 结果总数 lofP$
*/ S/dj])g
publicint getCount(){ z&yVU<;
return count; Mh]4K"cs
} j937tn!Q
.f&Z+MQ
publicvoid setCount(int count){ 31cZ6[
this.count = count; 2=7:6Fw
}
)=AWgA
/sr.MT
/** yVWt%o/
* 本结果所在的页码,从1开始 cCs@[D#O1
* d)GR]^=r
* @return Returns the pageNo. 5E^P2Mlc
*/ (dwb{+HW
publicint getP(){ RQU-]qQ8BM
return p; E+cx8(
} 8>`8p0I$+
Oj
'^Ww m
/** $B`ETI9g-N
* if(p<=0) p=1 Vg}+w Nt5
* ;?C`Jagx
* @param p |lN=q44I
*/ L@.Trso
publicvoid setP(int p){ 1d OB|
if(p <= 0) d2fiPI7lg
p = 1; ;@qQ^!g2
this.p = p; f.0HIc
} @H}{?-XyA
5Gm8U"UR
/** jT`u!CwdT
* 每页记录数量 U/ax`_
*/ pnUL+UYeM
publicint getNum(){ PZj}]d `
return num; 5w5"rcV
} 0E9 lv"3o
,/Q`gRBh"
/** SgkW-#
* if(num<1) num=1 i
^,
$/
*/ 5?.!A
'zb
publicvoid setNum(int num){ P| ftEF
if(num < 1) 8S5Q{[ !
num = 1;
J^!wk9q
this.num = num; k ~4o`eA
} E {UhM q7
f|Nkk*9$
/** >M^:x-mib
* 获得总页数 XB a^
A
*/ *ZIX76y<!A
publicint getPageNum(){ %~P3t=r
return(count - 1) / num + 1; N{<5)L~Y
} !Wj`U$];
jOZ>^5}
/** E8 5TCS1
* 获得本页的开始编号,为 (p-1)*num+1 AoY!f'Z
*/ W6):IW(E
publicint getStart(){ rNICK2Ah
return(p - 1) * num + 1; 1Se2@WR'
} (:R5"|]@<x
Pm QeO*f+
/** 5sSAH
* @return Returns the results. _o&NbDH
*/ lT~WP)
publicList<E> getResults(){ k"E|E";B
return results; yv: Op\;R
} %S^:5#9
AC!yc(^<
public void setResults(List<E> results){ nI] zRduC
this.results = results; S5r.so
} [E/. r{S
eN`G2eE
public String toString(){ v1/Y0
StringBuilder buff = new StringBuilder /#SH`ZK
1GPBqF
(); `l %,4qR
buff.append("{"); {REGoe=W%
buff.append("count:").append(count); >h.HW
buff.append(",p:").append(p); rr>6;
buff.append(",nump:").append(num); K5z<n0X ~
buff.append(",results:").append OTNI@jQ)
@'y8* _
(results); Df$~=A}
buff.append("}"); s[VYd:}se
return buff.toString(); c4zGQoeH:
} olKM0K
)u0/s'
} 4UND;I&
[;UI8Stw
GNSh`Tm =#