Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ",@g
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (Q}ijwj
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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 J)&+y;.
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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 *iN]#)3>
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分页支持类: ! yUKNR
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java代码: m1Z8SM+
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package com.javaeye.common.util; QI{Y@xQ
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import java.util.List; 71ybZ 0
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publicclass PaginationSupport { 4T^WRS
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publicfinalstaticint PAGESIZE = 30; U,(+rMeY0
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privateint pageSize = PAGESIZE; 6 Izv&
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privateList items; hiM!htc;M
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privateint totalCount; daNIP1Qn
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privateint[] indexes = newint[0]; "Y0[rSz,UW
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privateint startIndex = 0; KO"iauW
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public PaginationSupport(List items, int o~>go_Y
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totalCount){ k3kqgR*
setPageSize(PAGESIZE); aE$p;I
setTotalCount(totalCount); a5&j=3)|
setItems(items); g>oLc6T
setStartIndex(0); =h!m/f^x
} oOz6Er[KO
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public PaginationSupport(List items, int 5q>u
}J
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totalCount, int startIndex){ Vs{sB*:
setPageSize(PAGESIZE); /q]@|5I
setTotalCount(totalCount); M 4?3l
setItems(items); V>SA3
setStartIndex(startIndex); |Ay#0uQ5Y
} }y/t~f+
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public PaginationSupport(List items, int y}`%I&]n
+w5?{J
totalCount, int pageSize, int startIndex){ gk`.8o
setPageSize(pageSize); s1q d/
setTotalCount(totalCount); S22 ;g
setItems(items); uI wyan-
setStartIndex(startIndex); lEs/_f3;A
} 3!x)LUWfWY
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publicList getItems(){ de=T7,G#
return items; LlqhZetS
} .&dcJh*O+
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publicvoid setItems(List items){ (*tJCz`Sj
this.items = items; &x #5-O'
} >?KyPp
KS_d5NvYl
publicint getPageSize(){ Q0-~&e_'
return pageSize; w6 .HvH-@?
} `rV,<
| <$O5b'
publicvoid setPageSize(int pageSize){ kA0^~
this.pageSize = pageSize; Lf9h;z>#
} ^g\%VIOD
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publicint getTotalCount(){ #>'0C6Xn
return totalCount; /-lmfpT
} 2F(j=uV+
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publicvoid setTotalCount(int totalCount){ *<1m
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if(totalCount > 0){ UHWunI S
this.totalCount = totalCount; d8 po`J#nb
int count = totalCount / ZW"J]"A
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pageSize; ?1sY S
if(totalCount % pageSize > 0) [R$4n-$
count++; fBmx +7
indexes = newint[count]; #s%$kYp 1
for(int i = 0; i < count; i++){ QWEK;kUa@
indexes = pageSize * :08UeEy
Iq *7F5B
i; *XuzTGa"
} 9Wn0YIc
}else{ VM`."un]
this.totalCount = 0;
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} KtE`L4tW6
} /~:ztv\$M"
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publicint[] getIndexes(){ BlCKJp{m$
return indexes; QPnc "!
}
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publicvoid setIndexes(int[] indexes){ (WC<X Kf
this.indexes = indexes; M-_)CR
} sr4K-|@
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publicint getStartIndex(){ y- YYDEl
return startIndex; H b.oKo$T
} bmLNR
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publicvoid setStartIndex(int startIndex){ 9z#IdY$a
if(totalCount <= 0) 0Sk{P>A
this.startIndex = 0; Sl1N V
elseif(startIndex >= totalCount) Lfor0-j
this.startIndex = indexes 4|qp&%9-
p%BO:%v
[indexes.length - 1]; #,sJd ^uI
elseif(startIndex < 0) EifYK
this.startIndex = 0; jp|wc,]!
else{ ^H'#*b0u
this.startIndex = indexes K^+B"
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[startIndex / pageSize]; (@ Bw@9
} 9Bn
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} 7">.{
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publicint getNextIndex(){ v-o/zud]]
int nextIndex = getStartIndex() + m(Oup=\%b}
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pageSize; +_<#8v
if(nextIndex >= totalCount) 4d O>L"
return getStartIndex(); u4Sa4o
else lWR
return nextIndex; v'uQ'CiH
} IKt9=Tx
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publicint getPreviousIndex(){ fN9hBC@
int previousIndex = getStartIndex() - ^U1;5+2G+~
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pageSize; |Z<adOg
if(previousIndex < 0) *+G K?Ga
return0; V}( "8L
else S9.jc@#.`
return previousIndex; 7W*OyH^
} (L\tp>
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} W\Gg!XsLk
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抽象业务类 0
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java代码: D^pAf/ek@i
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/** E'C[+iK6,
* Created on 2005-7-12 !j(R_wOq
*/ ~DSle 3
package com.javaeye.common.business; 2iUF%>
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import java.io.Serializable; !"wIb.j}0
import java.util.List; QRRZMdEGs[
up`6IWlLE
import org.hibernate.Criteria; *Hs5MXNu
import org.hibernate.HibernateException; Lczcz"t
import org.hibernate.Session; :r\<DVj
import org.hibernate.criterion.DetachedCriteria; Tb}b*d3
import org.hibernate.criterion.Projections; ALG +
import }"szL=s
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org.springframework.orm.hibernate3.HibernateCallback; |i|O9^*%
import $wBUu
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org.springframework.orm.hibernate3.support.HibernateDaoS ?HW*qD#k
m~}nM |m%
upport; }5A?WH_
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import com.javaeye.common.util.PaginationSupport; wBr0s*1I
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public abstract class AbstractManager extends Ay{4R
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HibernateDaoSupport { {P*RA'H3G
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privateboolean cacheQueries = false; a+Z/=YUR
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privateString queryCacheRegion; m$U2|5un&
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publicvoid setCacheQueries(boolean +UB. M
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cacheQueries){ S -im
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this.cacheQueries = cacheQueries; H:CwUFL
} \E n ^Vf
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publicvoid setQueryCacheRegion(String |d{4_o90
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queryCacheRegion){ 5YRa2#d
this.queryCacheRegion = M]oaWQu
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queryCacheRegion; &n['#7 <(!
} WXJ%bH
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publicvoid save(finalObject entity){ 1"i/*}M
getHibernateTemplate().save(entity); w'}b 8m(L
} fi1tF/`
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publicvoid persist(finalObject entity){ +"Ka #Z
getHibernateTemplate().save(entity); d}Q;CF3m:
} i7iL[+f]Q
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publicvoid update(finalObject entity){ O
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getHibernateTemplate().update(entity); <_h
} BeBa4s
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publicvoid delete(finalObject entity){ X'O3)Yg
getHibernateTemplate().delete(entity); Wq]^1g_
} M4`qi3I
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publicObject load(finalClass entity, >]FRHJo_
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finalSerializable id){ '};pu;GA7
return getHibernateTemplate().load 4v Ug:'DM
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(entity, id); l7\Bq+Q
} I_\j05
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publicObject get(finalClass entity, !?,rcgi
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finalSerializable id){ ca5Ir<mL
return getHibernateTemplate().get L2+~I<|>
}qxwNmx
(entity, id); 6V W&An[6r
} +hGr2%*0f
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publicList findAll(finalClass entity){ kyMWO*>|
return getHibernateTemplate().find("from \s<L2uRj
T=%,^
" + entity.getName()); 4 1q|R[js!
} r761vtC#
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publicList findByNamedQuery(finalString O,u$L
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namedQuery){ cJ=0zEv
return getHibernateTemplate x:4:G(
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().findByNamedQuery(namedQuery); 4YMX;W
} N
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publicList findByNamedQuery(finalString query, )CKPzNf
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finalObject parameter){ t[VA|1gG
return getHibernateTemplate 22$M6Qof]n
"&W80,O3
().findByNamedQuery(query, parameter); {W,&jC
} kIrb;bZ+l
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publicList findByNamedQuery(finalString query, },+ &y^
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finalObject[] parameters){ j"1#n? 0
return getHibernateTemplate DxoW,GW
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().findByNamedQuery(query, parameters); OlI|.~
} 4SlEc|'7@
j`7q7}
publicList find(finalString query){ Bq@_/*'*Y
return getHibernateTemplate().find bi~1d"j
}hRw{#*8
(query); ozB2L\D7
} 9vZ:oO
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publicList find(finalString query, finalObject F=EG#<@u
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parameter){ OXp(rJ*bK
return getHibernateTemplate().find #q?'<''d,
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(query, parameter); B63puX{u#
} 0 7b=Zhh
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public PaginationSupport findPageByCriteria P.aN4 9`=
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(final DetachedCriteria detachedCriteria){ RqB 8g
return findPageByCriteria *!NxtB!LC
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Dk%+|c
} }l"pxp1K
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public PaginationSupport findPageByCriteria }ff+RGxLIG
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(final DetachedCriteria detachedCriteria, finalint Nk2n&(~$
[] cF*en
startIndex){ _3%eIyk4T
return findPageByCriteria u'`eCrKT*
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(detachedCriteria, PaginationSupport.PAGESIZE, tzJ7wXRr
"rA-u)Te
startIndex); z|bAZKSRYx
} QlE]OAdB42
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public PaginationSupport findPageByCriteria Y#[xX2z9
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(final DetachedCriteria detachedCriteria, finalint };Pdn7;1G:
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pageSize, BD,J4xH;
finalint startIndex){ g>E.Snj}
return(PaginationSupport) k@Qd:I;;
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getHibernateTemplate().execute(new HibernateCallback(){ 4ibOVBG:*,
publicObject doInHibernate #?"^: ,Y
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(Session session)throws HibernateException { ,J(shc_F
Criteria criteria = ^|%u%UR
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detachedCriteria.getExecutableCriteria(session); 'C7$,H'
int totalCount = 70-nAv
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((Integer) criteria.setProjection(Projections.rowCount <c%
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()).uniqueResult()).intValue(); d k/f_m
criteria.setProjection F1*xY%Jv^M
^ 6b27_=
(null); +\-cf,WkI
List items = :'2h0
5R
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criteria.setFirstResult(startIndex).setMaxResults
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# Rhtaq9
(pageSize).list(); x7GYWK
9
PaginationSupport ps = ]w0_!Z&
[2{2w68D!
new PaginationSupport(items, totalCount, pageSize, Gv&%cq1
,n{R,]y\
startIndex); A01PEVd@A
return ps; lk*wM?Z
} `ztp u
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}, true); m<sCRWa-
} RiG]-K:
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public List findAllByCriteria(final tH=jaFJ
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DetachedCriteria detachedCriteria){ GC`/\~TM
return(List) getHibernateTemplate v,|jmv+:
[}I|tb>Pg
().execute(new HibernateCallback(){ 9zl-C*9vj
publicObject doInHibernate MbxJ3"@
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(Session session)throws HibernateException { _Un*x5u2O
Criteria criteria = ?f= ~Pn+
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detachedCriteria.getExecutableCriteria(session); 3tW}a`z9
return criteria.list(); ivg W[]
} 3aw-fuuIb
}, true); 9^7z"*@#
} 4k!>JQor
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public int getCountByCriteria(final &D91bT+L
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DetachedCriteria detachedCriteria){ ,zEPdhTX
Integer count = (Integer) T_[5 ZYy
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getHibernateTemplate().execute(new HibernateCallback(){ JmC2buO
publicObject doInHibernate (&-I-#i
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(Session session)throws HibernateException { D+u\ORj
Criteria criteria = t>P[Yld"
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detachedCriteria.getExecutableCriteria(session); [0D.+("EW
return >}B53.;.k
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criteria.setProjection(Projections.rowCount LJA
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5Y 7 %Z
()).uniqueResult(); H2'djZ
} $F1Am%
}, true); +7{8T{
return count.intValue(); oT|:gih5
} @~&|BvK% \
} `# :(F z
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用户在web层构造查询条件detachedCriteria,和可选的 Y4+iNdd
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7pN&fAtj/
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PaginationSupport的实例ps。 r`$P60,@C
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ps.getItems()得到已分页好的结果集 MO?
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ps.getIndexes()得到分页索引的数组 )Fw#]~Z
ps.getTotalCount()得到总结果数 y Ni3@f
ps.getStartIndex()当前分页索引 hY/qMK5
ps.getNextIndex()下一页索引 Kpkpr`:)]
ps.getPreviousIndex()上一页索引 "EVf1iQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 gH.$B'
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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 e0]#vqdO
JLjb'Bn
一下代码重构了。 (,tL(:c
Xy}>O*
我把原本我的做法也提供出来供大家讨论吧: {P3gMv;
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首先,为了实现分页查询,我封装了一个Page类: mz<X$2]?
java代码: Y-,S_59
:QF`Orb!^
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/*Created on 2005-4-14*/ ,."wxP2u
package org.flyware.util.page; RU~Pa+H
TEbIU8{Y
/** i6S["\h>
* @author Joa 1d$wP$
* QVah4wFL*.
*/ GP x+]Jw8\
publicclass Page { C`uL
4r
>|0I\{C
/** imply if the page has previous page */ 1ed^{Wa4$9
privateboolean hasPrePage; {suQ"iv
}rnu:7
/** imply if the page has next page */ og_ylCh:
privateboolean hasNextPage; BjHp3-A'
8bf@<VTO_
/** the number of every page */ E&Zt<pRf;2
privateint everyPage; fl40jo]
8@){\.M
/** the total page number */ a
p( PI?]X
privateint totalPage;
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/** the number of current page */ YDZB$?&a
privateint currentPage; c[;A$P=
8.
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/** the begin index of the records by the current sGh TP/
EWq
< B)
query */ wKoar
privateint beginIndex; 6B Hdc
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/** The default constructor */ 9?^0pR p
public Page(){ .krEfY&
F=PBEaX
} We*uZ?+
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/** construct the page by everyPage ^E)8Sb9t
* @param everyPage Galh _;=
* */ m|;gl|dTB
public Page(int everyPage){ m8eoD{
this.everyPage = everyPage; y3bL\d1
} +Y2D @K?)
~Q]/=HK
/** The whole constructor */ mE'HRv
public Page(boolean hasPrePage, boolean hasNextPage, H_ NoW
~S<}q6H.
9yu#G7
int everyPage, int totalPage, YRv}w3yQ
int currentPage, int beginIndex){ uZ+"-Ig
this.hasPrePage = hasPrePage; &i6JBZ#~,
this.hasNextPage = hasNextPage; c Y+n 6k5
this.everyPage = everyPage; NC YOY
this.totalPage = totalPage; vst;G-ys
this.currentPage = currentPage; e`+ej-o,
this.beginIndex = beginIndex; `Gx
5=Bm;
} |oQhtk8.
m 0Uu2Z4
/** p^Z|$aZZ
* @return [.$/o}
* Returns the beginIndex. p9!jM\(
*/ 32pPeYxB!-
publicint getBeginIndex(){ bx Wzm|
return beginIndex; K.Cx 9
} [#AI! -
7\H_9o0$
/** vg1E@rH|}
* @param beginIndex k4!p))ql
* The beginIndex to set. H`yUSB
IP
*/ T hVq5
publicvoid setBeginIndex(int beginIndex){ &V%faa1
this.beginIndex = beginIndex; sp_19u
} $O fZp<M
.&Sjazk0XO
/** 0IHAoV60
* @return \5a;_N[Ed
* Returns the currentPage. @y6^/'
*/ aU$8 0
publicint getCurrentPage(){ ~wcp&D
return currentPage; K_;?Sr=
} [<}W S}
.
zFY$^Oz"_
/** +x?8\
* @param currentPage };'~@%U]/
* The currentPage to set. .R#<Q
*/ 9)n3f^,Oj*
publicvoid setCurrentPage(int currentPage){ QVmJ_WT
this.currentPage = currentPage;
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} o*[[nK*fL
NFG~PZ`6R
/** YpG6p0
nd
* @return 67||wh.BU
* Returns the everyPage. umpa!q};
*/ n"vO?8Sx
publicint getEveryPage(){ 6aWNLJ@
return everyPage; V<U9Pj^?^
} q AsTiT6r
C?<[oQb#
/** f'tQLF[r<
* @param everyPage Z}IuR|=
* The everyPage to set. +O8}twt@
*/ <d[GGkY]=
publicvoid setEveryPage(int everyPage){ M=1~BZQ(Z
this.everyPage = everyPage; E};1
H
} 4KW_#d`t
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/** [t*-s1cq
* @return @# .a5
* Returns the hasNextPage. roIc1Ax:
*/ a,:Nlr3
publicboolean getHasNextPage(){ Sg(\+j=
return hasNextPage; _+Uf5,.5yU
} {>Qs+]
COxJ,v(
/** 6rlM\k@!
* @param hasNextPage b86c[2
* The hasNextPage to set. Ng*O/g`%L
*/ xo(>nFjo
publicvoid setHasNextPage(boolean hasNextPage){ WpkCFp
this.hasNextPage = hasNextPage; `0=j,54cx
} N*KM6j
" "CNw-^t
/** u~Y+YzCxV
* @return V9;IH<s:
* Returns the hasPrePage. Vp8!-[R
*/ j k])S~xl?
publicboolean getHasPrePage(){ ph3dm\U.
return hasPrePage; C2L=i3R
} JycC\s+%E
DRRy5+,I
/** }9Q<<a
* @param hasPrePage &hWYw+yH\
* The hasPrePage to set. , lBHA+@
*/ h0l_9uI
publicvoid setHasPrePage(boolean hasPrePage){ NRs%q}lX
this.hasPrePage = hasPrePage; R1/mzPG
} b\xse2#
b^<7@tY
/** J& D0,cuk
* @return Returns the totalPage. j^Ln\N]^
* iUS?xKN$~-
*/ F[X;A\
publicint getTotalPage(){ ALKzR433/
return totalPage; >6'brb
} jVSU]LU E
h~#.s*0.F
/** Hc\oR(L
* @param totalPage irn
}.e
* The totalPage to set. -)e(Qt#ewl
*/ %,udZyO3uR
publicvoid setTotalPage(int totalPage){ }jL4F$wC
this.totalPage = totalPage; ItG|{Bo
} n&E/{o(
X-SR0x
} ,(kaC.Em
J^mm"2
oho~?.F
WAVEwA`r
iv6bXV'N
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 t k+t3+
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个PageUtil,负责对Page对象进行构造: lR^W*w4y
java代码:
zzX9Q:
@Z@S;RWSU
#/WjKr n
/*Created on 2005-4-14*/ /$UWTq/C7
package org.flyware.util.page; l^v,X%{Iz
lH>6;sE
import org.apache.commons.logging.Log; 9YwS"~Q =w
import org.apache.commons.logging.LogFactory; =jvN8R*[
^;cJjl'=
/** Kxsj_^&|i
* @author Joa r6e!";w:U
* ZRC7j?ui8`
*/ 4Gsq)i17j
publicclass PageUtil { S{~j5tQv^q
lp5b&I_
privatestaticfinal Log logger = LogFactory.getLog ,fyqa
t=dZM}wj_\
(PageUtil.class); $# b
,.,Y{CP
/** V V Aw y6
* Use the origin page to create a new page 9<*<-x{A17
* @param page 2*0n#"
L
* @param totalRecords w%kaM=
* @return %&4\'lE
*/ Xgo`XsA
publicstatic Page createPage(Page page, int }Q{4G
C,5Erb/
totalRecords){ QtfLJ5vi
return createPage(page.getEveryPage(), pEiq;2{~Yn
2spK#0n.HV
page.getCurrentPage(), totalRecords); ,jMV
#H[
} g)iw.M2
zfUkHL6
/** xf8.PqVNo
* the basic page utils not including exception rB3b
Bzr}+J
handler
58/\
* @param everyPage .%mjE'
* @param currentPage i-&"1D[&
* @param totalRecords *q(HW
* @return page 2$oGy
*/ CIf""gL9
publicstatic Page createPage(int everyPage, int Xd9<`gu
W7
9.,#
currentPage, int totalRecords){ Bqb3[^;~
everyPage = getEveryPage(everyPage); M,N(be-
currentPage = getCurrentPage(currentPage); qAuq2pHA+d
int beginIndex = getBeginIndex(everyPage, v5`Odbc=w
%gXNWxv
currentPage); Y^uYc}
int totalPage = getTotalPage(everyPage, 8j!(*'J.
p9iCrqi
totalRecords); _ 4+=S)$
boolean hasNextPage = hasNextPage(currentPage, ] Oe[;<I
m{0u+obi&w
totalPage); JT 5+d ,
boolean hasPrePage = hasPrePage(currentPage); u5dyhx7
\EEU G^T
returnnew Page(hasPrePage, hasNextPage, vX}mwK8
everyPage, totalPage, |n.ydyu`
currentPage, |b)N;t
O;<YLS^|6
beginIndex); =|bW >y
} eR5+1b
nB86oQ/S
privatestaticint getEveryPage(int everyPage){ 1V1T1
return everyPage == 0 ? 10 : everyPage; !)'|Y5 o
} 69/qH_Y
$6\W8v
privatestaticint getCurrentPage(int currentPage){ vghn+P8
return currentPage == 0 ? 1 : currentPage; c9;oB|8|
} 7$I *ju_
.AZ+|?d
privatestaticint getBeginIndex(int everyPage, int cOEzS
FI(M 1iJ
currentPage){ U>_#,j
return(currentPage - 1) * everyPage; 9:6d,^X
} *gXm&/2*
7S9Q{
privatestaticint getTotalPage(int everyPage, int 9TW
+)K yG
totalRecords){ We*c_;@<
int totalPage = 0; X+XbIbUuL
nzORG
if(totalRecords % everyPage == 0) ecy41y'~:
totalPage = totalRecords / everyPage; MEn#MT/Cz
else _i{4 4zE
totalPage = totalRecords / everyPage + 1 ; VR0#"
H[8P]"*z*i
return totalPage; o M#S.f?
} ^7~w yAr
.:#6dG\0z
privatestaticboolean hasPrePage(int currentPage){ YJ^TO\4WM
return currentPage == 1 ? false : true; @Ao E>
} jj 9eFB
"t"&6\
privatestaticboolean hasNextPage(int currentPage, >zAI#N4
k|T0Bly3P
int totalPage){ kXbdR
return currentPage == totalPage || totalPage == !4G<&hvb
H=k*;'
0 ? false : true; v;@-bED(Qs
} `+0)dTA(g$
yLlAK,5P0o
+,$"%C
} mg^\"GC*8
#`H^8/!e
wh;E\^',n
in6iJ*E@'
L)ry!BuHI
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #FV(a ~
o<-+y\J8K
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 D`^9
u
K
?V&[U
做法如下: O(E-ox~q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sIJ37;ZA
;"/ "
的信息,和一个结果集List: [0G>=h@u
java代码: +2ih!$T;7>
I"=XM
/aB9pD+%
/*Created on 2005-6-13*/ O}3M+
package com.adt.bo; %7?v='s=
OAQ'/{~7
import java.util.List; ,FPgbs
+>5
"fs$Y
import org.flyware.util.page.Page; \l leO|m
D:HeP:.I
/** cNG6 A4
* @author Joa 1xo<V5
*/ =>CrZ23B"
publicclass Result { ^$y_~z3o#7
BE}qwP^
private Page page; lA<IcW
k|7XC@i]%
private List content; 'm=9&?0S
r8M/E
lbk
/** $*H>n!&
* The default constructor LHWh-h(s
*/ A4?_0:<
public Result(){ &~Q ?k
super(); JPk3T.qp
} LV 94i
Sk$XC
/** X3Vpxtb
* The constructor using fields n.y72-&v
* AsM""x1Ix
* @param page pz^"~0o5
* @param content F7 7[fp
*/ <_H0Q_/(
public Result(Page page, List content){ b`K~l'8
this.page = page; T+2I:W%
this.content = content; z@ A5t4+3
} 1W
HR;!u
? F fw'O
/** $/45*
* @return Returns the content. \o@b5z]e
*/ 9ffRY,1@
publicList getContent(){ nx,67u/Pb
return content; N_r*Ig
} ap9eQsC
3<msiCP
/** {R,rc!yF
* @return Returns the page. %2oLND}?z
*/ R< xxwjt
public Page getPage(){ |_~BV&g,N
return page; $zz=>BOk
} .?S#DS )
sa+:c{
/** 2#1FI0,Pa*
* @param content 6M$.gX
G.
* The content to set. lLtC9:
*/ ^O\tN\g;c
public void setContent(List content){ Ze Shn
this.content = content;
VV]{R'
} 4'9h^C&
sS(^7GARa
/** =GM!M@~,Ab
* @param page HA"dw2|
* The page to set. xYt{=
*/ JEBo!9
publicvoid setPage(Page page){ "Jnq~7]
this.page = page; ? *I9
} W.:kE|a.g
} %v~j10e
7X}_yMxc
o<l4}~a
N??<3j+Iu
T*h+"TmE
2. 编写业务逻辑接口,并实现它(UserManager, >cMU<'&
S^D ~A8u
UserManagerImpl) <)n
java代码: #^#)OQq]
|Be.r{l
-R7f/a8
/*Created on 2005-7-15*/ R?|_`@@A
package com.adt.service; N}FG%a
!FpMO`m
import net.sf.hibernate.HibernateException; 4
<]QMA0
Cv$TNkP*
import org.flyware.util.page.Page; cS ];?tqrA
4N` MY8',
import com.adt.bo.Result; #2HygS
aeBth{
/** 4VU5}"<
* @author Joa ~Nc]`95
*/ "hlIGJ?_=
publicinterface UserManager { oHi&Z$#!n
s^KxAw_IV
public Result listUser(Page page)throws |+`hSA
W+K=M*^D;c
HibernateException; &*)tqQeQf
BTd'bD~EA
} LK:|~UV?
6gR=e+
[[s k
Y?%6af+
@MB;Ez
v
java代码: >9u6@
5E!|-xD
^jmnE.8R
/*Created on 2005-7-15*/ /
V{w<
package com.adt.service.impl;
0U/:Tpyr
*iC
t4J
import java.util.List; B-&J]H
Cq(Xa-
import net.sf.hibernate.HibernateException; Y6D=tb
ryn)
import org.flyware.util.page.Page; hCxL4LrF
import org.flyware.util.page.PageUtil; Bgs~1E @8V
3.dUMJ$_
import com.adt.bo.Result; jZ{S{"j
import com.adt.dao.UserDAO; |[{;*wtv
import com.adt.exception.ObjectNotFoundException; 9C4l@jrF
import com.adt.service.UserManager; r
2
lP9I\Ge&
/** VhW;=y>}
* @author Joa /d{L]*v)]
*/ +qz)KtJS
publicclass UserManagerImpl implements UserManager { 9lD,aOb
l[fNftT-
private UserDAO userDAO; EhD|\WLx!
2Qy!Aa
/** yZ!Eu#81
* @param userDAO The userDAO to set. )$]+R?v
*/ } 1XLe
publicvoid setUserDAO(UserDAO userDAO){ j{;3+LCo*
this.userDAO = userDAO; >6kWmXK[
} 3x=F
_E30t( _.
/* (non-Javadoc) k]>k1Mi=
* @see com.adt.service.UserManager#listUser ;Q"F@v}18
(%P* rl
(org.flyware.util.page.Page) `r iv`+J{s
*/ @Op8^8$`
public Result listUser(Page page)throws l =_@<p
~.@fk}'R
HibernateException, ObjectNotFoundException { .nSupTyG
int totalRecords = userDAO.getUserCount(); Z956S$gS
if(totalRecords == 0) Qrt8O7&('
throw new ObjectNotFoundException 7K;dVB
/ P:Hfq
("userNotExist"); 0}^-, Q,
page = PageUtil.createPage(page, totalRecords); DS$ _"'g%i
List users = userDAO.getUserByPage(page); Fhsmpe~
returnnew Result(page, users);
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} |v1 K@
fN4pG*D
} eN-{
vXnpx}B
{tT`It
~NcJLU!au
NuooA
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 cdfll+
xBZ9|2Y s
询,接下来编写UserDAO的代码: kCC9U_dj,
3. UserDAO 和 UserDAOImpl: v|/3Mi9mz
java代码: xXx`a\i
h#n8mtt&i
;OPCBd r
/*Created on 2005-7-15*/ Z*TW;h0ZQ3
package com.adt.dao; _kx
EU@mrm?
import java.util.List; <zf+Ii1:,
y="SzPl
import org.flyware.util.page.Page; V%0.%/<#5
rgYuF,BT.
import net.sf.hibernate.HibernateException; $HXB !$d
0%qUTGj
/** (En\odbvt
* @author Joa ~r!5d@f.6
*/ -+9x 0-P
publicinterface UserDAO extends BaseDAO { wrO>#`Z
vW{cBy
publicList getUserByName(String name)throws tT8jC:oVa
.#:,j1L"53
HibernateException; L~oFW'
y{{EC#
publicint getUserCount()throws HibernateException; n>E*g|a
ft'iv
publicList getUserByPage(Page page)throws ,SyUr/D
!U#++Zig%
HibernateException; x7@WWFF>
r~}}o o4K
} )*A,L%
'<0q"juXE
q%k+x)
)a^Yor)o"
bSr 'ji
java代码: 6oP{P_Pxi
h3kHI?jMWG
(v`;ym
/*Created on 2005-7-15*/ #8z,'~\
package com.adt.dao.impl; w}Upa(dU
=_'cG:=)
import java.util.List; 7RP_
^Cr+
N-rmk
import org.flyware.util.page.Page; /SXz_e
qp W#!Vbx
import net.sf.hibernate.HibernateException; 2ZO'X9
import net.sf.hibernate.Query; j>o +}p?3I
bJ|?5
import com.adt.dao.UserDAO; =GQ^uVf1
y^AA#kk
/** '!-?
* @author Joa fl"y@;;#h
*/ 9 <KtI7
public class UserDAOImpl extends BaseDAOHibernateImpl x
ctU.)p
Idlu1g
implements UserDAO { |sFe:TX
|nEVOy>'
/* (non-Javadoc) s\W
* @see com.adt.dao.UserDAO#getUserByName M?B(<j1Ri
IMGqJc,7
(java.lang.String) ~B&*7Q7
*/ pIu H*4Vz
publicList getUserByName(String name)throws %;Z bQ9
j#e.rNG
HibernateException { #eC;3Kq#-
String querySentence = "FROM user in class ;:c%l.Y2
BZ?W>'B%$
com.adt.po.User WHERE user.name=:name"; e_=pspnZ
Query query = getSession().createQuery Z02s(y=k1
16QbB;
(querySentence); z`/.v&<>V
query.setParameter("name", name); #Q3PzDfj
return query.list(); RW7oL:$dt
} c[ony:6
=$8@JF'
/* (non-Javadoc) [S]!+YBK
* @see com.adt.dao.UserDAO#getUserCount() d=Do@)
m|
*/ cIr1"5POXK
publicint getUserCount()throws HibernateException { {(OIu]:
int count = 0; e5ru:#P.p
String querySentence = "SELECT count(*) FROM *>'2$me=
cHL]y0>
user in class com.adt.po.User"; hRr1#'&
Query query = getSession().createQuery Y_@"v#,
A$~xG(
(querySentence); =u8D!AxT
count = ((Integer)query.iterate().next fT3*>^Uv
v'Vt
.m&9&
()).intValue(); #\;>8
return count; 9>Uq$B
} (s"iC:D6U
C6d]tLE
/* (non-Javadoc) 'yd@GQM&
* @see com.adt.dao.UserDAO#getUserByPage 90T%T2K
Lq-33#n/
(org.flyware.util.page.Page) |:9Ir^
*/ 5}eQaW48
publicList getUserByPage(Page page)throws ,k~j6Z
um jhG6
HibernateException { y|.fR>5
String querySentence = "FROM user in class rAx"~l.=
Wu!t C
com.adt.po.User"; s^>lOQ=
Query query = getSession().createQuery N\q)LM !M
iS"8X#[]N
(querySentence); XY{:tR_al
query.setFirstResult(page.getBeginIndex()) VI24+h'J
.setMaxResults(page.getEveryPage()); )_8}53C
return query.list(); |=cCv_y
} zBt`L,^
:,kU#eZ$-
} Vf0fT?/K
\ CK(;J
JA)o@[lF
"#twY|wW
Cqgk
至此,一个完整的分页程序完成。前台的只需要调用 %f(S'<DhC
JzMZB"Z?
userManager.listUser(page)即可得到一个Page对象和结果集对象 pDq#8*q+v
#9`r XEz
的综合体,而传入的参数page对象则可以由前台传入,如果用 =4zNo3IvL+
vJRnBq+y
webwork,甚至可以直接在配置文件中指定。 W7L+8LU;
4TUtY:
下面给出一个webwork调用示例: ~o@\
n
java代码: :)p)=c8%
JoCA{Fa}
,;.B4
/*Created on 2005-6-17*/ EqnpMHF
package com.adt.action.user; {pDTy7!Hs
UP;Q= t
import java.util.List; wmo{YS3t|
5Lsm_"0
import org.apache.commons.logging.Log; lc[XFc
import org.apache.commons.logging.LogFactory; a}KK{Vqo`
import org.flyware.util.page.Page; `l/:NF
xQJIM.
import com.adt.bo.Result; VLsh=v
import com.adt.service.UserService; XDk'2ycv
import com.opensymphony.xwork.Action; qL|
5-(P
B6bOEPQ
/** H`m:X,6}
* @author Joa oYz!O]j;a
*/ tAqA^f*{
publicclass ListUser implementsAction{ ~BZXt7DE
j z~[5m}J
privatestaticfinal Log logger = LogFactory.getLog ;8P_av}C
o]Wz6L
(ListUser.class); (kIz
pI7Ssvi^
private UserService userService; X9fNGM1
TDlZ!$g(
private Page page; e?V,fzg
~G>jw"r
privateList users; TbLe6x
vv+D*e&<
/* *hVb5CS
* (non-Javadoc) BeK2;[5C
* Ge~q3"
* @see com.opensymphony.xwork.Action#execute() k-"<{V
*/ ]9jZndgC
publicString execute()throwsException{ __!m*!sd
Result result = userService.listUser(page); Y@Y`gF6F
page = result.getPage(); Ic'Q5kfM
users = result.getContent(); R]u
(l+`
return SUCCESS; lv4(4$T
} ]cIu|bRO
~,ynJ]_aJB
/** ./l|8o
* @return Returns the page. .APVjqG
*/ }A|))Ao|
public Page getPage(){ Wo{K}
return page; 0G5'Y;8
} x>%joKY[
E0QPE5_
/** Xo Y7/&&
* @return Returns the users. t5paYw-b
*/ vMhYpt?7\
publicList getUsers(){ :BZMnCfA
return users; R2w`Y5#`
} &5u BNpH
*g1L$FBG
/** dK.R[aQ
* @param page 6xarYh(
* The page to set. iJ)0Y~
*/ pI>*u ]x
publicvoid setPage(Page page){ %M9;I
this.page = page; 7 _g+^e-"
} x;j{}
%
==N` !+
/** 66Gx.tE
* @param users EKuSnlTXba
* The users to set. \~>e_;
*/ ExCM<$,
publicvoid setUsers(List users){ WL l_'2h
this.users = users; T~X41d\
} q#NR32byF
aG!
*WHt
/** Ky kSFB
* @param userService %c X"#+e
* The userService to set. >,"sHm}l%
*/ ,=|4:F9
publicvoid setUserService(UserService userService){ `
W4dx&
this.userService = userService; rjUBLY1(
} V^n0GJNo
} JrDHRIkgm
B3mS]
\D?:J3H*]
~*}$>@f{[X
WPo:^BD
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, =&7@<vBpy
=g~W%})
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 +tt9R_S
zAs&%OjG
么只需要: \9)#l#m
java代码: 9#k0_vDoW
A
WHU'
?x3Jv<G0*
<?xml version="1.0"?> :.uk$jx
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork J02^i5l
Es.nHN^]%K
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 1fFj:p./l_
LjaGyj>)
1.0.dtd"> UTCzHh1
,l HLH
<xwork> {)@D`{$
{.CMD9F[
<package name="user" extends="webwork- >A}0Ho
LA4<#KP
interceptors"> ;`(R7X
*3
iW;i!,
<!-- The default interceptor stack name 5~+XZA#2
cin2>3Z$
--> |g-b8+.=]
<default-interceptor-ref e1/sqXWo
n ~,tQV
name="myDefaultWebStack"/> ^Ga&}-
%=Tr^{i
<action name="listUser" ;..o7I
sJZ!sznn
class="com.adt.action.user.ListUser"> 8TWTbQ
<param NfzF.{nh
=o^|b ih
name="page.everyPage">10</param> WeMAe
w/d
<result R7?29?$7
|`O7nOM
name="success">/user/user_list.jsp</result> `rb>K
</action> 4(cJ^]wb ^
".U^ifF
</package> riCV&0"n
WE6\dhJ<
</xwork> }Ln@R~[
~/-eyxLTm
-rSIBc:$8
{fDTSr?/
vF4]ux&
|L::bx(
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 #X`8dnQZ
K84^Oq
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。 ^G|98yc!'
xT*d/Oa w
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 jz'<
g(hOg~S\E
'#\1uXM1U?
h<6UC%'ac
2/7_;_#vJ%
我写的一个用于分页的类,用了泛型了,hoho TgfrI
\Kavw
java代码: ^G1%6\We
Yu3zM79'k
~i~%~doa
package com.intokr.util; @jy41eIo
K#mOSY;}
import java.util.List; \7v)iG|#G&
QM<y`cZ8
/** .Y*f2A.v
* 用于分页的类<br> },@^0UH4c
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Ykqyk')wm
* ?1I GYyu!
* @version 0.01 3l1cyPv
* @author cheng jO~:<y3
=
*/ X~9j$3lUBR
public class Paginator<E> { =L-I-e97@
privateint count = 0; // 总记录数 F<&!b2)ML
privateint p = 1; // 页编号 LnsD
privateint num = 20; // 每页的记录数 Ao9R:|9
privateList<E> results = null; // 结果 DcD{*t?x
1zxq^BI
/** 0CExY9@Wq
* 结果总数 &1|?BZv
*/ FnFb[I@eu
publicint getCount(){ EbY,N:LK
return count; 'gMfN
} ]wVk+%e
YT#3n
publicvoid setCount(int count){ ]lO h&Cz[
this.count = count; /+]s.V.
} s
+s" MI
C.Uju`3
/** pB:$lS
* 本结果所在的页码,从1开始 Orn0Zpp<z
* ]T:;Vo
* @return Returns the pageNo. 'jg3
*/
q2aYEuu,
publicint getP(){ N)2f7j4C&
return p; Z.PBu|Kx
} *fMpZ+;[m
AyKMhac
/** NAC_pM&B
* if(p<=0) p=1 p=Q0!!_r
* TUK"nKSZ`.
* @param p G3i !PwW
*/ =+:{P?*}
publicvoid setP(int p){ :mppv8bh
if(p <= 0) -Z-f1.Dm5
p = 1; )u%je~Vw
this.p = p; ~&dyRtW4
} feM6K!fL`
ZP\M9Ja
/** bm~W
EX
* 每页记录数量 C4$:mJ>y
*/ Sl2iz?
publicint getNum(){
-fI`3#
return num; }L=/A7Nk>
} N"tFP9;K
BR`ygrfe
/**
df}r% i
* if(num<1) num=1 <W8t|jt
*/ 4*n#yVb/
publicvoid setNum(int num){ S[3iA~)Z-
if(num < 1) XN=67f$Hw
num = 1; ,_.I\EY[
this.num = num; I=)hWC/
} Cwa^"r3P1
/1=4"|q>h'
/** Rd
\.:u
* 获得总页数 c,MOv7{x_
*/ 7cP@jj
publicint getPageNum(){ <*ZJaBwWU~
return(count - 1) / num + 1; \W5O&G-C
} JCx
WWre
+j_;(Gw7
/** |y;}zQB-dH
* 获得本页的开始编号,为 (p-1)*num+1 )>
,wj
*/ d_UN0YT<
publicint getStart(){ B(a-k?
return(p - 1) * num + 1; v4,h&JLt
} !l?.5Pm])
$4kH3+WJ
/** -&x2&WE'
* @return Returns the results. GG064zPq7
*/ wcSyw2D
publicList<E> getResults(){ }0#U;_;D
return results; r`y ezbG
} u-Ddq~;|
hd\gH^wk
public void setResults(List<E> results){ *K!|@h{60
this.results = results; /n~\\9#3
} -C-?`R
)UgX3+@
public String toString(){ (s<Dd2&.H
StringBuilder buff = new StringBuilder ;7]u!Q
5,qj7HZF
(); _R'Fco
buff.append("{"); ZRxZume<f
buff.append("count:").append(count); }VS3L_
;}/
buff.append(",p:").append(p); oF9
-&
buff.append(",nump:").append(num); Va,<3z%O<
buff.append(",results:").append F^"_TV0va
WG*t::NN
(results); >^q7c8]~g
buff.append("}"); XZ&KR.C,
return buff.toString(); AqKz$
} fx=Awba
_It ,%<3
} ]V %.I_
D0k
8^
e0@6Pd