Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?*U:=|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 6E:5w9_=c
7, :l\t
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 c *Pt;m
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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 !Y]%U @4}
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分页支持类: J y0TV jA
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java代码: -<gQ>`(0
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package com.javaeye.common.util; vjXCArS
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import java.util.List; %J|xPp)
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publicclass PaginationSupport { q|R$A8)L.
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publicfinalstaticint PAGESIZE = 30; l`RFi)u~&
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privateint pageSize = PAGESIZE; o|c"W}W
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privateList items; AV["%$:
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privateint totalCount; =`BPGfCb
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privateint[] indexes = newint[0]; N!=Q]\ZD
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privateint startIndex = 0; WevXQ-eKm
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public PaginationSupport(List items, int vpqMKyy
d`4@aoM
totalCount){ X+k`UM~
setPageSize(PAGESIZE); vD4<G{
setTotalCount(totalCount); h}(GOYS)
setItems(items); AZjj71UE
setStartIndex(0); pNR69/wGi
} W/|C
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public PaginationSupport(List items, int {uMqd-Uu
(L6*#!Dt
totalCount, int startIndex){ _7 9 ?,U]
setPageSize(PAGESIZE); 'P?DZE
setTotalCount(totalCount); *;C8g{
setItems(items); s_ N]$3'[E
setStartIndex(startIndex); vxC,8Z
} `` mi9E
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public PaginationSupport(List items, int {^n\
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totalCount, int pageSize, int startIndex){ C]+T5W\"<B
setPageSize(pageSize); &OSyU4r
setTotalCount(totalCount); tqo!WuZAj
setItems(items); (">gLr
setStartIndex(startIndex); 13T0"}
} )z#M_[zC>
`L=$,7`
publicList getItems(){ .8%mi'0ud
return items; b,#E.%SLw
} <\cH9D`dE
6|D,`dk3U
publicvoid setItems(List items){ +tXOP|X
this.items = items; ly]n2RK
} #TX=%x6
H -,RzL/
publicint getPageSize(){ *AU"FI>V
return pageSize; {E~MqrX
} sR. ecs+
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publicvoid setPageSize(int pageSize){ txwTJScg
this.pageSize = pageSize; _8'F I_E3
} uvrfR?%QK
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publicint getTotalCount(){ jF\J+:5M
return totalCount; k+S 6)BQ7U
} SdfrLdi}Y
1+^L,-k!
publicvoid setTotalCount(int totalCount){ =R^V[zTn_
if(totalCount > 0){ {-]/r
this.totalCount = totalCount; o?J>mpC
int count = totalCount / fxQN
Ir*,fyl
pageSize; ;Db89Nc$
if(totalCount % pageSize > 0) P~0d'Oi
count++; w%1B_PyDg
indexes = newint[count]; 8P 3EQY-
for(int i = 0; i < count; i++){ 9 0[gXj
indexes = pageSize * OZ q/'*
B*owV%
i; %&"_=Lc
} Iy](?b
}else{ T]nZ3EZ
this.totalCount = 0; 1Ly?XNS
} qx"?')+
} $2^V#GWo
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publicint[] getIndexes(){ 'B"kUh%3$5
return indexes; C<6IiF[>%
} =ot`V; Q>
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publicvoid setIndexes(int[] indexes){ zk4yh%Cd_
this.indexes = indexes; I/GZ
} T"Wq:
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publicint getStartIndex(){ /s=TLPm
return startIndex; z1LATy
} .l*]W!L]
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publicvoid setStartIndex(int startIndex){ h2KXW}y"4
if(totalCount <= 0) mB#`{|1[
this.startIndex = 0; u9>.x
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elseif(startIndex >= totalCount) o"v>
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this.startIndex = indexes ?S0VtHQ
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[indexes.length - 1]; Gz!72H
elseif(startIndex < 0) jo<[|ZD
this.startIndex = 0; C
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else{ N`grr{*_
this.startIndex = indexes bs]ret$?(q
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[startIndex / pageSize]; DSy,#yA
} x-Z`^O
} m{x!uq
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publicint getNextIndex(){ 4%p5X8|\ih
int nextIndex = getStartIndex() + tB[(o%k
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pageSize; G+'MTC_
if(nextIndex >= totalCount) +&a2aEXF
return getStartIndex(); "`,PLC
else 3T Q#3h
return nextIndex; \Ul*Nsw
} '4FS.0*_
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publicint getPreviousIndex(){ rQ*'2Zf'<
int previousIndex = getStartIndex() - f;pR8
N!"GwH
pageSize; 5HL JkOV5
if(previousIndex < 0) 9|Jmj @9
return0; < W/-[ M
else nf/iZ &
return previousIndex; zG@9-s* L
} ~@BV
xHykU;p@
} tmK@Veb*a'
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5&2=;?EO
抽象业务类 dm.?-u;C
java代码: t wtGkkC
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uTP=kgYqJ
/** q'+XTal
* Created on 2005-7-12 SP
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*/ w:'$Uf8]
package com.javaeye.common.business; A[ /0on5r
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import java.io.Serializable;
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import java.util.List; cdzzS?$)
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import org.hibernate.Criteria; )V)4N[?GC
import org.hibernate.HibernateException; ?)4|WN|c_
import org.hibernate.Session; mN3%;$ND7
import org.hibernate.criterion.DetachedCriteria; >\}2("bv
import org.hibernate.criterion.Projections; JYm@Llf)$
import X-oou'4<
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org.springframework.orm.hibernate3.HibernateCallback; ,!%[CpM3
import 09|d<
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org.springframework.orm.hibernate3.support.HibernateDaoS a/_sL(F{
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upport; nm %ka4
7ou2SL}k
import com.javaeye.common.util.PaginationSupport; 7i334iQZ
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public abstract class AbstractManager extends Sr2c'T"
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HibernateDaoSupport { z56W5g2
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privateboolean cacheQueries = false; 2c8,H29
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privateString queryCacheRegion; `9S<E
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publicvoid setCacheQueries(boolean *|euC"5c
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cacheQueries){ 7:M%w'oR
this.cacheQueries = cacheQueries; (zJ
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} rU.ew~
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publicvoid setQueryCacheRegion(String H[]j6D
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queryCacheRegion){ 2R2Z6}
this.queryCacheRegion = u^ngD64
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queryCacheRegion; m&2<?a}l
} N1#*~/sXh
1|z>}
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publicvoid save(finalObject entity){ OWOj|jM
getHibernateTemplate().save(entity); er l_Gg
} A[oi?.D
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publicvoid persist(finalObject entity){ qMI%=@=
getHibernateTemplate().save(entity); ]lZ!en
} $ZQP f
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publicvoid update(finalObject entity){ _4%+TN6z
getHibernateTemplate().update(entity); @#8F5G#
} zpg*hlv
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publicvoid delete(finalObject entity){ [0MVsc=
getHibernateTemplate().delete(entity); /JR*X!&"
} _5.7HEw>/
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publicObject load(finalClass entity, hz\7Z+ $L_
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finalSerializable id){ x8zUGvtQ
return getHibernateTemplate().load z4{|?0=C
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(entity, id); q ,}W.
} q'c'rN^
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publicObject get(finalClass entity, QabF(}61
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finalSerializable id){ 6\b B#a
return getHibernateTemplate().get ;znIY&Z
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(entity, id); ~poy`h'
} #p=/P{*
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publicList findAll(finalClass entity){ @uT\.W:Q2
return getHibernateTemplate().find("from nuKjp Ap!
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" + entity.getName()); U.?,vw'aai
} WBTX~%*U
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publicList findByNamedQuery(finalString uF@Q8 7G
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namedQuery){ ic?6p
return getHibernateTemplate gZ/M0px
cq@8!Eu w]
().findByNamedQuery(namedQuery); (AXSQI~y
} mpXco *!_
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publicList findByNamedQuery(finalString query, pS*vwYA
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finalObject parameter){ H.wp{m{
return getHibernateTemplate 'iUfr@
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().findByNamedQuery(query, parameter); 'S@C,x%2,
} *9?-JBT&F
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publicList findByNamedQuery(finalString query, ~i6tcd
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finalObject[] parameters){ J<u,Y= -~
return getHibernateTemplate 0=L:8&m
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().findByNamedQuery(query, parameters); q9icj
} xr)kHJ:v
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publicList find(finalString query){ }T4"#'`
return getHibernateTemplate().find *sZOws<
f=g/_R2$xN
(query); ,MuLu,$/
} p24sWDf
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publicList find(finalString query, finalObject FU5vo
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parameter){ ]%ikr&78u
return getHibernateTemplate().find
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tezsoR!.ak
(query, parameter); 7PHvsd"]p
} VO#]IXaP
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ byyz\>yAVq
return findPageByCriteria `3/,-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); )?I1*(1{A
} :$dGcX}
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public PaginationSupport findPageByCriteria AX<TkS@wjb
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(final DetachedCriteria detachedCriteria, finalint n M,m#"AI
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startIndex){ T_y 'cvh
return findPageByCriteria =JX.*
MEB
9)e`mO*n
(detachedCriteria, PaginationSupport.PAGESIZE, ) m%ghpX
9k& lq$
startIndex); c^Rz?2x
} 'O
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public PaginationSupport findPageByCriteria vn6/H8
k2,n:7
(final DetachedCriteria detachedCriteria, finalint -gv@
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pageSize, +mMn1&
finalint startIndex){ 2JUX29rER
return(PaginationSupport) ;)u}`4~L
n|yl3v
getHibernateTemplate().execute(new HibernateCallback(){ y%v<Cp@R
publicObject doInHibernate :-Ho5DHg
@@'zMV%
(Session session)throws HibernateException { LV4x9?&
Criteria criteria = M5: f^
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detachedCriteria.getExecutableCriteria(session); q !EJs:AS
int totalCount = 7==Uz?}C
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((Integer) criteria.setProjection(Projections.rowCount 0$":W
"n7rbh3VW
()).uniqueResult()).intValue(); j K$4G.x
criteria.setProjection "z=A=~~<{
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(null); p%]*I?
List items = V`pTl3
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criteria.setFirstResult(startIndex).setMaxResults ryW1OV6?_0
8}{';k
(pageSize).list(); 7$8z}2
PaginationSupport ps = T9*\ITA
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new PaginationSupport(items, totalCount, pageSize, 9hmCvQgtf
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startIndex); #fk)Y1
return ps; cx_[Y
} {QM;%f
}, true); Q7N4@w;e
} OcQ_PE5\
})M$#%(
public List findAllByCriteria(final A AH-Dj|&l
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DetachedCriteria detachedCriteria){ )gmDxD
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return(List) getHibernateTemplate wTf0O@``6H
Mpk^e_9`<
().execute(new HibernateCallback(){ j<szQ%tJlI
publicObject doInHibernate ,b-wo
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(Session session)throws HibernateException { .sbU-_ij@U
Criteria criteria = xv$^%(Ujp
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detachedCriteria.getExecutableCriteria(session); %,K |v
return criteria.list(); Zv7@
} R`76Ae`R8
}, true); { )'D<:T
} a_waLH/
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public int getCountByCriteria(final ,h#!!j\j6
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DetachedCriteria detachedCriteria){ @Sq=#f/=
Integer count = (Integer) 9`4h"9dO
,*E%D _
getHibernateTemplate().execute(new HibernateCallback(){ D4
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publicObject doInHibernate smIZ:L%
}ebw1G
(Session session)throws HibernateException { a}i{b2B
Criteria criteria = Q,#M
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detachedCriteria.getExecutableCriteria(session); iV'-j,-i
return O<6/0ub&+h
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criteria.setProjection(Projections.rowCount AA>5h<NM
By3dRiM=,2
()).uniqueResult(); +FY-r[_~
} ua|qL! L+
}, true); _\@i&3hkx
return count.intValue(); }K<;ygcWE@
} 1G.+)*:3
} +
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用户在web层构造查询条件detachedCriteria,和可选的 JGj_{|=:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 MYN1zYT6j
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PaginationSupport的实例ps。 I=(O,*+PQ
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ps.getItems()得到已分页好的结果集 elKQge
ps.getIndexes()得到分页索引的数组 yA%[u.{
ps.getTotalCount()得到总结果数 }ZVNDvGH
ps.getStartIndex()当前分页索引 t&eD;lg :
ps.getNextIndex()下一页索引 ~Rv U+D
ps.getPreviousIndex()上一页索引 f1=8I_>=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ^+GN8LUs
A%Bz52yg
,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 //wmJ |
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一下代码重构了。 kY_UY~E
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我把原本我的做法也提供出来供大家讨论吧: @F3 d9t-
:"QRB#EC%
首先,为了实现分页查询,我封装了一个Page类: C{2UPG4 x
java代码: %+pXzw`B
P `2Rte6s
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/*Created on 2005-4-14*/ Q| xPm:
package org.flyware.util.page; rtzxMCSEU
b%)a5H(
/** >Zr/U!W*?
* @author Joa .pdgRjlSn
* As)-a5!
*/ P AKh v.7
publicclass Page { *S=v1 s/
x1Si&0T0P<
/** imply if the page has previous page */ F[ ? t"d
privateboolean hasPrePage; nZ%<2
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/** imply if the page has next page */ Y:byb68
privateboolean hasNextPage; 90ORx\Oeo
PMTyiwlm
/** the number of every page */ \}<nXn!
privateint everyPage; #[i({1`^L
QTLOP~^
/** the total page number */ ,>~92
privateint totalPage; T
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c^=,@#
/** the number of current page */ ^$T>3@rDB
privateint currentPage; EL+}ab2S
n=yFw\w'
/** the begin index of the records by the current +Uk/Zg
w^
\y0abxIHS
query */ F-ijGGL#
privateint beginIndex; )D#*Q~
)fC^h=Qp
4{J%`H`Q!
/** The default constructor */ A46y?"]/30
public Page(){ 2} T"|56
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} G,$jU9 f
k'S/nF A
/** construct the page by everyPage z}pdcQl#
* @param everyPage _$F I>
* */ 9cj:'KG)!
public Page(int everyPage){ K\;b3
this.everyPage = everyPage; p'_*>%4~
} scA&:y
>S!QvyM(V
/** The whole constructor */ fc&4e:Ve
public Page(boolean hasPrePage, boolean hasNextPage, XRaq\a`=:
#5'9T:8
)TP7gLv=b
int everyPage, int totalPage, M#2DI?S@
int currentPage, int beginIndex){ tTP"*Bb
this.hasPrePage = hasPrePage; }t]CDa_n
this.hasNextPage = hasNextPage; -,p(PK
this.everyPage = everyPage; d7l0;yR&+
this.totalPage = totalPage; eyUo67'7
this.currentPage = currentPage; pYVQ-r%QF
this.beginIndex = beginIndex; :,:r
} D[9eu>"'9M
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/** Nno*X9>~
* @return e>MC
3D`5
* Returns the beginIndex. *R8q)Q
*/ J6|5*|*^
publicint getBeginIndex(){ Li iQ;x
return beginIndex; :3u>%
} YB~}!F [(
*qGxQ?/
/** q]<cn2
* @param beginIndex W}nD#9tL
* The beginIndex to set. 7pmhH%Dn$
*/ )CEfG
publicvoid setBeginIndex(int beginIndex){ Qnph?t>
this.beginIndex = beginIndex; vA:1z$m
} :SziQQ
leX&py
/** b`fPP{mG
* @return GuNzrKDr
* Returns the currentPage. ti3T?_
*/ /J8y[aa
publicint getCurrentPage(){ -AJe\ J 2
return currentPage; jBarY g
} Z6A*9m
Tf<1Z{9
/** Y6&w0~?!
* @param currentPage J9zSBsp_
* The currentPage to set. @|idlIey
*/ Bc`jkO.q
publicvoid setCurrentPage(int currentPage){ tc.R(F96
this.currentPage = currentPage; w?Cqe
N
} 3g`uLA X>u
X@2[!%nm
/** lqTTTk
* @return B{PI&a9~s%
* Returns the everyPage. ,dLh`t<\
*/ nGZZCsf <
publicint getEveryPage(){ JUt
7
return everyPage; pPu E-EDk
} )xy1DA
=rMT1
/** x$tx!%,)/S
* @param everyPage 4RGEg;]S
* The everyPage to set.
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*/ PV<=wc^
publicvoid setEveryPage(int everyPage){ !ZJ"lm
this.everyPage = everyPage; ]v{f!r=}
} ,`ST Va-
/GD4GWv :
/** )
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* @return M{<cqxY
* Returns the hasNextPage. s`B]+
*/ ]d=SkOq
publicboolean getHasNextPage(){ ~ODm?k
return hasNextPage; sKVN*8ia
} 8D@H4O.
mtSOygd
/** 3(0k!o0"
* @param hasNextPage .$pW?C 3e
* The hasNextPage to set. MF)Xc\}0p
*/ a|Io)Qhr
publicvoid setHasNextPage(boolean hasNextPage){ ]r8t^bqe
this.hasNextPage = hasNextPage; ~8L*N>Y
} YBqu7&
A[`c2v-hF
/** ;jS2bc:8a
* @return #Mkwd5S|L
* Returns the hasPrePage. uu@Y]0-
*/ %{WZ
publicboolean getHasPrePage(){ M0zJGIT~b
return hasPrePage; ~47Bbom
} $<cio
X
yr?*{;
/** mN
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* @param hasPrePage J/X{
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* The hasPrePage to set. S<HR6Xw
*/ Z]kk.@P
publicvoid setHasPrePage(boolean hasPrePage){ qKNX^n;
this.hasPrePage = hasPrePage; ?0
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} ]wFKXZeK
8s(?zK\
/** E^B*:w3
* @return Returns the totalPage. 4gbi?UAmX
* mCOJ1}
*/ -;9pZ'r
publicint getTotalPage(){ AT Dm$ *
return totalPage; `2`Nu:r^
} x dDR/KS
:?W {vV
/** FdwT
* @param totalPage 'NCxVbyYD
* The totalPage to set. ]4~-
z3=y
*/ G%0G$3W"
publicvoid setTotalPage(int totalPage){ Xvu|ss
this.totalPage = totalPage; uis;S)+
} Xb +)@Y4h
i\hH .7G1
} Y8!T4dkn
[GKSQt{)
$T7hY$2Ql
j$r .&,m
]yu,YZ@7
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 'A@[a_
/LMb~Hy,
个PageUtil,负责对Page对象进行构造: 3&i8C,u]/O
java代码: Cw;&{jY
S~^0
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C {.{>M
/*Created on 2005-4-14*/ $tvGS6p>
package org.flyware.util.page; 2}`Q9?
2y;
|6`
import org.apache.commons.logging.Log; 8\c=Un
import org.apache.commons.logging.LogFactory; 1o)Vzv
BOqq=WY
/** ONQp-$
* @author Joa J]uYXsC
* +o&E)S}wP
*/ L8-
publicclass PageUtil { )Y':u_Lo
tV2SX7N
privatestaticfinal Log logger = LogFactory.getLog INwc@XB
~N+lI\K
(PageUtil.class); wqDRFZ1*P
Ycb<'M*jE
/** #sit8k`GR8
* Use the origin page to create a new page !fdni}f)
* @param page pJ7wd~wF*
* @param totalRecords js
)G
* @return X'N4a
*/ Gjuc"JR7
publicstatic Page createPage(Page page, int 8OC5L1
Y{y #us1
totalRecords){ YN4P
>d
return createPage(page.getEveryPage(), =DTn9}u
lv9Ss-c4
page.getCurrentPage(), totalRecords); z79L2lJn
} S8j;oJ2d
.FK'TG
/** j}8IT
* the basic page utils not including exception *|AnL}GJ
0O4'Ts ?
handler )>at]mH
* @param everyPage R7T"fN
* @param currentPage ;}IF'ANA
* @param totalRecords ]OY6.m
* @return page W#'c6Hq2c
*/ &:L8; m
publicstatic Page createPage(int everyPage, int >rlQY>5pH
_J&u{
currentPage, int totalRecords){ aq"E@fb
everyPage = getEveryPage(everyPage); `(aU_r=
currentPage = getCurrentPage(currentPage); !Dkz6B*
int beginIndex = getBeginIndex(everyPage, y<PPO6u7
93fKv
currentPage); ,: w~-
int totalPage = getTotalPage(everyPage, IC[SJVH;
c}vy9m$B_
totalRecords); .^#{rk
boolean hasNextPage = hasNextPage(currentPage, @&+h3dV.V
=pWpHbB.
totalPage); =B1t?("
boolean hasPrePage = hasPrePage(currentPage); ^w2n
)ACa0V>*p
returnnew Page(hasPrePage, hasNextPage, MS^,h>KI
everyPage, totalPage, w ;H
currentPage, SrK;b .
3D\.Sj%
beginIndex); <)Kjf/x
} g^)> -$=
2EE/xnwX
privatestaticint getEveryPage(int everyPage){ i40r}?-
return everyPage == 0 ? 10 : everyPage; toTAWT D
} f;u;hQxs
6z%3l7#7Yi
privatestaticint getCurrentPage(int currentPage){ 1sc #!^Oo
return currentPage == 0 ? 1 : currentPage; MBcOIy[&A
} b{sE#m%r
Kox~k?JK
privatestaticint getBeginIndex(int everyPage, int .NjdkHYR
a^[io1}-
currentPage){ (~Zg\(5#
return(currentPage - 1) * everyPage; UMhM8m!=o
} BqZLqGOKu
O-T/H-J`
privatestaticint getTotalPage(int everyPage, int jn}6yXB
" "a+Nc
totalRecords){ qwFn(pK[
int totalPage = 0; WtRy~5A2
4vqu(w8
L
if(totalRecords % everyPage == 0) Ur&: Rr
totalPage = totalRecords / everyPage; E=s`$ A
else 6\0GVM\
totalPage = totalRecords / everyPage + 1 ; ;k/0N~
dJ24J+9}]j
return totalPage; ) 0}o bPp
} &u=FLp5
%< j=&
privatestaticboolean hasPrePage(int currentPage){ G$@X>)2N8
return currentPage == 1 ? false : true; A5H[g`&
} a}>GQu*y
;'o>6I7Ph
privatestaticboolean hasNextPage(int currentPage, _l8oB)
f4tia.
int totalPage){ .{ x5(bi0S
return currentPage == totalPage || totalPage == #='#`5_5
Y(A?ib~K
0 ? false : true; nQ~q-=,L
} ,RT\&Ze5
{?L}qV
Q o=
} 'M'LJ.,"/
y4?>5{`W
*M`[YG19!e
rW6w1
X*Q7Yu
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 1gm{.*G
SfR!q4b=
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Ys3C'Gc
5rcno.~QO
做法如下: \@F{Q-
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 K
6G n
jS- QTG!=
的信息,和一个结果集List: ^|\?vA
java代码: hOC,Eo
tllg$CQ5
:-
5Mn3*
/*Created on 2005-6-13*/ }`g*pp*
package com.adt.bo; s3knh&'zb
9q5[W=|
import java.util.List; 4{Ak|
]E3g8?L
import org.flyware.util.page.Page; i)p__Is
#,9|Hr%
/** 50Jr(OeU<
* @author Joa 6x7=0}'
*/ nbRg<@
publicclass Result { *K 7L5.
Zu hT \l
private Page page; u,]yd*
Umd!j,
private List content; }v!6BU6<Q
axl?t|~I
/** eyG.XAP
* The default constructor g-s@m}[T
*/ M]{!Nx
public Result(){ t2gjhn^p
super(); WT)")0)[
} th<]L<BP/
W
| }Hl{}
/** t5qAH++axN
* The constructor using fields CG7LF
* {V&7JZl,/
* @param page -jy"?]ve.
* @param content IY:O? M
*/ !L_ SHlU
public Result(Page page, List content){ vOS0E^
this.page = page; ^`7t@G$ D
this.content = content; ?x0yiV~dL
} +NY4j-O
1L|(:m+
/** )-{~7@yqZ
* @return Returns the content. i<?4iwX%i*
*/ kA_3o)J
publicList getContent(){ MocH>^,
return content; 1`t?5|s>
} F~AS(sk
.g~@e_;):
/** {;E/l(HNI
* @return Returns the page. s*f.` A*)
*/ QFPx4F7(e
public Page getPage(){ \_E.%K
return page; {+:XVT_+
} u^9c`
Uz|]}t5V
/** qrc/Q;$
* @param content 4QNR_w
* The content to set. 3c3Z"JV
*/ mW-W7-JhO7
public void setContent(List content){ 8tMte!E
this.content = content;
I={{VQ
} -/%jeDKp
m-RY{DO+
/** gpWS_Dw9
* @param page o3qv945
* The page to set. ?m1$*j
*/ PNgMLQI6
publicvoid setPage(Page page){ E+zn\v
this.page = page; !@{[I:5
} &|'6-wD.
} Xb*_LZAU
lM*O+k
, ~xU>L^
(dF;Gcw+
)c/y07er
2. 编写业务逻辑接口,并实现它(UserManager, 9`xFZMd31A
z|*6fFE
UserManagerImpl) %k
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java代码: B5HdC%8/}
K)&XQ`&
-/c1qLdQ
/*Created on 2005-7-15*/ ZHlin#"
package com.adt.service; lO> 7`2x=F
5,BkwAr+6[
import net.sf.hibernate.HibernateException; -_DiD^UcXn
0DIM]PS
import org.flyware.util.page.Page; a=.db&;vY
j :Jdwf
import com.adt.bo.Result; FR^wDm$
#4 &N0IG
/** <S@mQJS!y
* @author Joa ' 5 qL
*/ `OReSg
2
publicinterface UserManager { G>S1Ld'MV
efkie}
public Result listUser(Page page)throws <VR&=YJ
w^E]N
HibernateException; Rn(F#tI
A|_%'8
} rI66frbj
:$Q]U2$mPS
Ox*T:5
FJ,\?ooGf
Doc'7P
java代码: zHc 4e
< Gy!i/
PSqtZN
/*Created on 2005-7-15*/ +6)kX4
package com.adt.service.impl; ySK Yqt z
%3#I:>si
import java.util.List; P}WhE
t2%@py*bU
import net.sf.hibernate.HibernateException; X.AWs=:-
VBsFT2XiL
import org.flyware.util.page.Page; lyH X#]
import org.flyware.util.page.PageUtil; m>-^K
OK2/k_jXN'
import com.adt.bo.Result; 9Bvn>+_K
import com.adt.dao.UserDAO; Z=Y_;dS9
import com.adt.exception.ObjectNotFoundException; a0/n13c?G
import com.adt.service.UserManager; t k/K0u
z'}= A
/** (VXx G/E3
* @author Joa I%Po/+|+
*/ )>X|o$2
publicclass UserManagerImpl implements UserManager { uZ`d&CEh
&0
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private UserDAO userDAO; )bCG]OM7<
07LL)v~
/** 73s3-DS,
* @param userDAO The userDAO to set.
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*/ Wh'_slDH+
publicvoid setUserDAO(UserDAO userDAO){ ;aK !eD$
this.userDAO = userDAO; x [{q&N!"`
} <&Y}j&(
HSr"M.k5
/* (non-Javadoc) 77&^$JpM
* @see com.adt.service.UserManager#listUser *CPB5s
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(org.flyware.util.page.Page) Yr"!&\[oz
*/ 9>[.=
public Result listUser(Page page)throws qp~4KukL
#SihedWi
HibernateException, ObjectNotFoundException { 0q>NE<L
int totalRecords = userDAO.getUserCount(); [,o5QH\Etq
if(totalRecords == 0) WP%{{zR$
throw new ObjectNotFoundException fBWJ%W
S `m-5
("userNotExist"); {sfmWVp
page = PageUtil.createPage(page, totalRecords); =4M.QA@lI!
List users = userDAO.getUserByPage(page); i^s`6:rNu
returnnew Result(page, users); x,w`OMQ}c
} '[=yfh
k}f<'g<H
} `3sy>GU?
.y;\puNq
_sf#J|kQ
we H@S
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 RP|>&I
'!yS72{$2
询,接下来编写UserDAO的代码: kuTq8p2E
3. UserDAO 和 UserDAOImpl: 9#EHXgz
java代码: "3Xv%U9@
LpiHoavv
aX[1H6&=7
/*Created on 2005-7-15*/ I4o=6ts
package com.adt.dao; 8=n9hLhqo
M ~ i+F0
import java.util.List; {#w A!>.
22al
import org.flyware.util.page.Page; MR?*GI's
~_l6dDJ
import net.sf.hibernate.HibernateException; d Y:|Ef|v(
n ,&/D
/** wZo.ynXT
* @author Joa #LN5&i;s
*/ H4}%;m%
publicinterface UserDAO extends BaseDAO { ]< s\V-y
*%OYAsc
publicList getUserByName(String name)throws m{bZRkt
I9[1U
HibernateException; d%#!nq{vd
F}6DB*
publicint getUserCount()throws HibernateException; XSm"I[.g
V9fGVDl;
publicList getUserByPage(Page page)throws H{\.g=01
tb:,Uf>E
HibernateException; @pF
fpHq?>
lC'{QUC
} |+Hp+9J
b)on A|
h&=O-5
}J ei$0x
w24{_ N
java代码: AW,v
[x2JFS#4
m,W) N9 M
/*Created on 2005-7-15*/ w(76H^e
package com.adt.dao.impl; j[J5y#
..t,LU@|
import java.util.List; B :.@Qi^
<Rcu%&;i
import org.flyware.util.page.Page; YCa@R!M*O
h>}ax\h
import net.sf.hibernate.HibernateException; Ds%9cp*6
import net.sf.hibernate.Query; w)+wj[6
E
[##`Um
import com.adt.dao.UserDAO; >5)<Uv$
k:b/Gq`
/** Y/.AUN
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* @author Joa {Ge+O<mD
*/ aWyUu/g<A`
public class UserDAOImpl extends BaseDAOHibernateImpl 96(R'^kNX
63W{U/*aao
implements UserDAO { Iz
DG&c
&&[zT/]P
/* (non-Javadoc) ojHhT\M`
* @see com.adt.dao.UserDAO#getUserByName K&=D-50%
>T<6fpXuk2
(java.lang.String) z{ptm7
*/ \)ip>{WG
publicList getUserByName(String name)throws +' %@!
Vclr)}5
HibernateException { QE|`&~sme
String querySentence = "FROM user in class g>so
R&*
w/ TKRCO3
com.adt.po.User WHERE user.name=:name"; i+g~ Uj}h
Query query = getSession().createQuery {m[s<A(
3KSpB;HX
(querySentence); -<_QF82
query.setParameter("name", name); S}[l*7
return query.list(); \V,c]I
} ; e@gO
iOX Z]Xj5
/* (non-Javadoc) axmsrjW#
* @see com.adt.dao.UserDAO#getUserCount() (S`6Q
*/ (
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publicint getUserCount()throws HibernateException { )l&D]3$6K
int count = 0; W{
fZ[z
String querySentence = "SELECT count(*) FROM c!It^*
iv*V#J>
user in class com.adt.po.User"; hq=,Z1J
Query query = getSession().createQuery kY"KD22a
*m9{V8Yi2
(querySentence); OOnX`
count = ((Integer)query.iterate().next H3, ut
t2-
^-g6
()).intValue(); LXj5R99S
return count; ciudRK63M
} %Tv^GP{}
*^]~RhjB
/* (non-Javadoc) y`yZR
_
* @see com.adt.dao.UserDAO#getUserByPage 3GF2eS$$P
/.Fj.6U5
(org.flyware.util.page.Page) T>A{qu
*/ C?4JXW
publicList getUserByPage(Page page)throws m#vL*]c}
E.`U`L
HibernateException { .7NNT18
String querySentence = "FROM user in class S=`+Ryc
20RXK1So
com.adt.po.User"; I6!5Yj]O"
Query query = getSession().createQuery 8~lIe:F-
>EsziRm
(querySentence); =&wmWy
query.setFirstResult(page.getBeginIndex()) d[ >`")2)
.setMaxResults(page.getEveryPage()); y&m0Lz53Z
return query.list(); @Ky> 9m{
} <*!i$(gn
^ KK_qC
} Ys+OB*8AE
N,dT3we
J5p"7bc
\c v?^AI
J7D}%
至此,一个完整的分页程序完成。前台的只需要调用 &3F}6W6A
IQ<MyB(
userManager.listUser(page)即可得到一个Page对象和结果集对象 9^"b*&>P
}?F`t[+
的综合体,而传入的参数page对象则可以由前台传入,如果用 %3q0(Xl
i,A#&YDl
webwork,甚至可以直接在配置文件中指定。 U[L9*=P;
%CwL:.|
下面给出一个webwork调用示例: 7|\@zQ h
java代码: 3f" %G\
j"^+oxH
n+@F`]Ke
/*Created on 2005-6-17*/ G+xt5n.%
package com.adt.action.user; <~TP#uAz
fkSO( C)
import java.util.List; 8dD2
D(p\0V
import org.apache.commons.logging.Log; `RU[8@ 2%
import org.apache.commons.logging.LogFactory; 9Zry]$0~R
import org.flyware.util.page.Page; YprHwL
D jk C
import com.adt.bo.Result; :j|IP)-f
import com.adt.service.UserService; |@ ,|F:h<M
import com.opensymphony.xwork.Action; dzK{
Z
DRqZ,[!+
/** MuoF FvAA
* @author Joa 7Dnp'*H
*/ RLlU"
sw+{
publicclass ListUser implementsAction{ k#[F`
L9pvG(R%
privatestaticfinal Log logger = LogFactory.getLog M/x >51<
y;mj^/SxK
(ListUser.class); f\'{3I29
!D!~^\
private UserService userService; (-]r~Ol^
x21dku<6K[
private Page page; gaA<}Tp,
QL6C,#6
privateList users; 1@u2im-O
{t};-q!v$j
/* H|cNH=
* (non-Javadoc) Dnc(l(
* + <,gB $j
* @see com.opensymphony.xwork.Action#execute() Ii7QJ:^
*/ 1c JF/"v
publicString execute()throwsException{ omWJJ|b~
Result result = userService.listUser(page); +T9:Udi
page = result.getPage(); ~|wbP6</:-
users = result.getContent(); TO%dw^{_`
return SUCCESS; .0R v(Y
} Y+K|1r
V]*b4nX7
/** eIl]oC7*
* @return Returns the page. qY\f'K}Q*
*/ Y>jiXl?&
public Page getPage(){ '`1CBU$
return page; 52upoU>}2
} ~=R SKyzt
8kP3+
/** m Sk5u 7
* @return Returns the users. Be+0NXLVy
*/ ?5kHa_^
publicList getUsers(){ RpLE
02U
return users; r-,e;o>9
} Zo>]rKeV
W2uOR{
'?
/** :$MG*/Q
* @param page
ccd8O{G.M
* The page to set. +l=r#JF
*/ R *F l8
publicvoid setPage(Page page){ Zw
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this.page = page; 02BuX]_0g
} {mB0rKVm
ePIiF_X
/** mDZ*E !B
* @param users ax
41N25
* The users to set. {nU=%w"\
*/ kA7mLrON
publicvoid setUsers(List users){ 'U'yC2BI n
this.users = users; HYmn:?H
} Le%ZV%,
Ali9pvE
/** u+{a8=
* @param userService }jill+]
* The userService to set. "fq{Y~F%`
*/ -(K9s!C!.
publicvoid setUserService(UserService userService){ S;]*) i,v
this.userService = userService; r_;9'#&'
} <id}<H
} 2k<;R':
}%D^8>S
<oz!H[!
z3uW)GQ.
}pJwj
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Y3O#Q)-j$
kY'T{Sm1^
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 awz;z?~
MTUn3;c/
么只需要: \(%Y%?dy
java代码: } CfqG?)
*YlV-C<}W"
FN[{s
<?xml version="1.0"?> EAeqLtFqs
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork o: ;"w"G
Q?X>E3=U
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 'MY/*k7:
tr7<]Hm:
1.0.dtd"> 3N_"rNKD
<\;#jF%V
<xwork> 'R_g">B.
r7',3V
<package name="user" extends="webwork- 6"}?.E$
Z>
r^SWL
interceptors"> K#"O
a
h
x.q+uU$^
<!-- The default interceptor stack name 6&/T@LQYrh
KIWe@e
--> 0tU.(
<default-interceptor-ref 8(* [Fe9
v,ju!I0.
name="myDefaultWebStack"/> .?l\g-;=
4R\Hpt
<action name="listUser" 1/"WD?a
AnT3M.>ek
class="com.adt.action.user.ListUser"> GI&h`X5,e
<param ^#sU*trr
6R^^ .tCs
name="page.everyPage">10</param> pxa(
<result SCz318n
r9dyA5oD
name="success">/user/user_list.jsp</result> /3{b%0Aa
</action> Ih"XV
"
W|%~h
</package> Q@HopiC
{E8~Z8tT
</xwork> ^(FdXGs[
0vw4?>Jf@
lg&t8FHa;
OE- gC2&Bm
&Udb9
5^x1cUB]
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 p }~qf
ruy}/7uf
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Pjc
Tx +
X93!bB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 FIsyiSY<j
BSVxN
a8UwhjFO
;-qO'V:;
;4pYK@9w_
我写的一个用于分页的类,用了泛型了,hoho 55fC~J<
y9Us n8
java代码: Kh_Lp$'0uM
#n8IZ3+
53n^3M,qK
package com.intokr.util; h3xAJ!
Bn &Ws
import java.util.List; W@I|Q -
Ob<{G"
/** mmk=97
* 用于分页的类<br> fd.^h*'mU
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "LlfOKG
* }|8_9Rx0*
* @version 0.01 Y<%@s}zc
* @author cheng LHo3
Niy.
*/ *(T:,PY
public class Paginator<E> { [UWdW
privateint count = 0; // 总记录数 m0a?LY
privateint p = 1; // 页编号 9~/J35
privateint num = 20; // 每页的记录数 =h5H~G5AT
privateList<E> results = null; // 结果 Su/6Q$0 t
abfW[J
/** yj.7'{mA
* 结果总数 =E#%'/ A;c
*/ Zm_UR*"
publicint getCount(){ c2'Lfgx4
return count; ^Dn D>h@q
} heC/\@B
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publicvoid setCount(int count){ gL*>[@RO
this.count = count; (G;lx
} ~ls[Sl@
.ufTQ?Fe
/** 1e{IC=
* 本结果所在的页码,从1开始
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* @v)p<r^M">
* @return Returns the pageNo. V8C:"UZ;
*/ b)qoh^
publicint getP(){ !W}9no
return p; xg;+<iW
} .yqM7U_
Z8@J`0x
/** 3yU.& k
* if(p<=0) p=1 Tz8PS k1[
* koZ*+VP=
* @param p CR"|^{G
*/ $!-c-0ub
publicvoid setP(int p){ Gi?/C&1T
if(p <= 0) 7WkB>cn
p = 1; }Mp:JPH&S4
this.p = p; Ybs\ES'?A
} C.Kh[V\Ut
^6MU
0Q2
/** 7XTkX"zKj
* 每页记录数量 i1NY9br
*/ 4U+xb>
publicint getNum(){ {GK;63`1
return num; '
V^6XI
} Vt %bI0#
~962i#&4
/** |,gc_G
* if(num<1) num=1 j,lT>/
*/ Zw5Ni Xj
publicvoid setNum(int num){ dJeNbVd
if(num < 1) `.~N4+SP
num = 1; !;Yg/'vD-
this.num = num; :cem,#(=
} hV8[@&Sx3
}Jy8.<Gd^
/** 4o
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* 获得总页数 e6R}0w~G
*/ dx5#\"KX=,
publicint getPageNum(){ y&q*maa[
return(count - 1) / num + 1; J%v=yBC2
} eL10Q(;P`
z&#SPH*
/** `w#Oih!6A|
* 获得本页的开始编号,为 (p-1)*num+1 I5 o)_nc
*/ VRWAm>u
publicint getStart(){ OE_XCZ!5P
return(p - 1) * num + 1; E4`N-3
} jSh5!6O
Vwg|K|
/** 1an^1!
* @return Returns the results. ,&]S(|2%>t
*/ ck ]Do!h
publicList<E> getResults(){ >Wm`v.-
return results; `18qbot
} T*8VDY7
FcR=v0),
public void setResults(List<E> results){ [w>$QR
this.results = results; B8.Pn
} 6}gls}[0{e
/ ;$#d}R
public String toString(){ *g:4e3Iy
StringBuilder buff = new StringBuilder !O+)sbd<
q
MfT>rH
(); `slL%j^"
buff.append("{"); ]e"=$2d$
buff.append("count:").append(count); 5L+>ewl
buff.append(",p:").append(p); N=4G=0 `ke
buff.append(",nump:").append(num); ^1S!F-H4\
buff.append(",results:").append V, Z|tB^
0[RL>;D:
(results); nF54tR[
buff.append("}"); j@W.&- _
return buff.toString(); ?Nup1!D
} N|8P)
u!!Y=!y*<
} 4^p5&5F
:By?O"LQ
+DW~BS3