Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?MM3LA! <
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 9M]"%E!s
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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 ~C'nBV
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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 #<Nvy9
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。 b:Kw_Q
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分页支持类: X3{1DY3@u
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java代码: *"FLkC4
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package com.javaeye.common.util; zL'IN)7MU
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import java.util.List; -!,]Y10
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publicclass PaginationSupport { PbUcbb17
@O}j:b
publicfinalstaticint PAGESIZE = 30; sLdUrD%
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privateint pageSize = PAGESIZE; Ln2C#Uf
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privateList items; Sn2Ds)Pfx3
qMES<UL>
privateint totalCount; k(z<Bm
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privateint[] indexes = newint[0]; A}bHfn|
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privateint startIndex = 0; 8='21@wrN
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public PaginationSupport(List items, int #A9_A%_.h
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totalCount){ M
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setPageSize(PAGESIZE); >Y-TwDaE
setTotalCount(totalCount); V/}>>4
setItems(items); ^[}0&_L
w
setStartIndex(0); 0j!ke1C&C
} 8V|jL?a~
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public PaginationSupport(List items, int R P:F<`DB|
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totalCount, int startIndex){ e=o{Zo?H=
setPageSize(PAGESIZE); mERrcY Y{
setTotalCount(totalCount); h2"|tTm,a
setItems(items); e9@fQ
setStartIndex(startIndex); j%Z{.>mJ
} !N8)C@=
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public PaginationSupport(List items, int M=[q+A
s i"`
totalCount, int pageSize, int startIndex){ 7s8<FyFsjd
setPageSize(pageSize); R #3Q$
setTotalCount(totalCount); .\~P -{Hd
setItems(items); w$lfR,
setStartIndex(startIndex); 4nII/cPG
} $wYuH9(
X!rQ@F3
publicList getItems(){ >}DjHLTW\
return items; #EmffVtY
} frmqBC VJ:
hG~]~ )
publicvoid setItems(List items){ {nPkb5xbW
this.items = items; 1%hM8:)i_
} VUy)4*
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publicint getPageSize(){ kyx SIQ^
return pageSize; 9VUm=Z#`
} |c
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publicvoid setPageSize(int pageSize){ &@W4^-9
this.pageSize = pageSize; 2&gVZ z
} Xh0wWU*
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publicint getTotalCount(){ g/l0}%
return totalCount; NT;x1
} O~#uQm
pcuMGo-#
publicvoid setTotalCount(int totalCount){ yF/< :
if(totalCount > 0){ *{.&R9#7U'
this.totalCount = totalCount; s0)qlm*
int count = totalCount / p&OJa$N$[
V+=*2?1
pageSize; =tS[&6/
if(totalCount % pageSize > 0) TDl!qp @
count++; !#c[~erNZ
indexes = newint[count]; yL;o{
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for(int i = 0; i < count; i++){ V5yxQb
indexes = pageSize * vfJ3idvo*w
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i; S< EB&P
} T6R7,Vt'v
}else{ EtR@sJ<
this.totalCount = 0; })zB".
} Jcalf{W6
} J-, H6u
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publicint[] getIndexes(){ m]0^
return indexes; !bZhj3.
} 2H?I'<NoC
Bbl)3$`,
publicvoid setIndexes(int[] indexes){ O^X[9vrW
this.indexes = indexes; m~Y'$3w
} vZ[$H
ZVdsxo<
publicint getStartIndex(){ .7pGx*WH^Y
return startIndex; Q{qj
} iHE0N6%q
-7-Fd_F8
publicvoid setStartIndex(int startIndex){ *xX(!t'
if(totalCount <= 0)
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this.startIndex = 0; ?AV&@EX2C
elseif(startIndex >= totalCount) ]cF1c90%
this.startIndex = indexes <\1}@?NGC
r^w\9a_
[indexes.length - 1]; 6(N.T+;]
elseif(startIndex < 0) Gd30Be2gd
this.startIndex = 0; #1QX!dK+
else{ C.yY8?|
this.startIndex = indexes 9UeVvH
+CnyK(V
[startIndex / pageSize]; |D;_:x9
} 9N~8s6Ob
} U^M@um M
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publicint getNextIndex(){ |5oKq'(b
int nextIndex = getStartIndex() + {yvb$ND|j{
Y!++CMzU
pageSize; Y<p zy8z
if(nextIndex >= totalCount) pu/m8
return getStartIndex(); F=oHl@
else [2GXAvXsT
return nextIndex; M1AZ}bc0]
} :DZLjC
@9OeC
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publicint getPreviousIndex(){ G 2%
int previousIndex = getStartIndex() - [;(]Jy
tA`mD >[
pageSize; *.kj]BoO
if(previousIndex < 0) >DDQ'W !
return0; !lR0w|
else KWFyw>*)
return previousIndex; ftYR,!&
} b@=zrhQ
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} V/aQ*V{
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抽象业务类 wrH7 pd
java代码: jZXVsd
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/** "DVt3E
* Created on 2005-7-12 25x cD1*
*/ n_<mPU
package com.javaeye.common.business; :fxWz%t
e{,!|LhpQ
import java.io.Serializable; yJnPD/i
import java.util.List; ]UK`?J=t2g
:&Qb>PH[
import org.hibernate.Criteria; 'n~fR]h}
import org.hibernate.HibernateException; sS
C?io
import org.hibernate.Session; OI~}e,[2z
import org.hibernate.criterion.DetachedCriteria; ]}BB/KQy^
import org.hibernate.criterion.Projections; CfQf7-
import fH-NU-"
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org.springframework.orm.hibernate3.HibernateCallback; HDyQzCG,
import 48wDf_<f5=
YV*b~6{d
org.springframework.orm.hibernate3.support.HibernateDaoS j._G7z/LJ
;5<P|:^
upport; 0r1g$mKb
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import com.javaeye.common.util.PaginationSupport; f.@Xjf
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public abstract class AbstractManager extends SEYG y+#K
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HibernateDaoSupport { ]} '^`
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privateboolean cacheQueries = false; mRCHrw?WG
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privateString queryCacheRegion; 1XG$ z@NN
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publicvoid setCacheQueries(boolean rxQ<4
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cacheQueries){ WS5A Y @(~
this.cacheQueries = cacheQueries; -<6v:Z
} ]K7`-p~T
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publicvoid setQueryCacheRegion(String !;i*\
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queryCacheRegion){ j5zFDh1(
this.queryCacheRegion = Z)NrhJC
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queryCacheRegion; 7k `_#
} dPHw3^J0j
<_t5:3HL
publicvoid save(finalObject entity){ U M@naU
getHibernateTemplate().save(entity); K${}r0
} zyDZ$Dhka
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publicvoid persist(finalObject entity){ SWT:frki`
getHibernateTemplate().save(entity); r]9 e^
} TaOOq}8c#
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publicvoid update(finalObject entity){ IK3qE!,&U
getHibernateTemplate().update(entity); @.k5MOn
} ^+M><jE9
lDC}HC
publicvoid delete(finalObject entity){ g&bwtEZ
getHibernateTemplate().delete(entity); |ixGY^3;
} y5_XHi@u~o
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publicObject load(finalClass entity, D{R/#vM jk
@m?{80;uQ
finalSerializable id){ ZY)%U*jWU
return getHibernateTemplate().load Pw= 3PvkL
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(entity, id); b{BaQ>.(`
} K}Na3}m
q@%h^9.
publicObject get(finalClass entity, ]/_G-2.R
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finalSerializable id){ M\dO({o
return getHibernateTemplate().get FOSbe]
)
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(entity, id); k Q~ %=pn
} |#V(p^
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publicList findAll(finalClass entity){ -?5$ PH
return getHibernateTemplate().find("from Q<yAT(w
*2=W5LaK.
" + entity.getName()); ) \4
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} QF.3c6O@
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publicList findByNamedQuery(finalString gH'_ymT=
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{ V0>iN:~S
namedQuery){ 7
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return getHibernateTemplate %9X{{_
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().findByNamedQuery(namedQuery); H UkerV
} 2 h<U
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publicList findByNamedQuery(finalString query, b_l3+'#ofM
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finalObject parameter){ U{}!y3[wK
return getHibernateTemplate Af9+HI
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Px#$uU
().findByNamedQuery(query, parameter); (f~gEKcB2u
} uB;_vC
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publicList findByNamedQuery(finalString query, -;>#3O-
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finalObject[] parameters){ um[!|g/
return getHibernateTemplate `L\)ahM
thptm
().findByNamedQuery(query, parameters); uY;R8CiD
} Fu%X
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publicList find(finalString query){ 5B{k\H;
return getHibernateTemplate().find l4 "\) ];
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(query); jTfi@5aPY
} g4wZvra6%)
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publicList find(finalString query, finalObject |1l&@#j!2
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parameter){ Mlj#b8
return getHibernateTemplate().find j o_
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(query, parameter); Qn.[{rw
} P"F{=\V1`<
jV^C19
public PaginationSupport findPageByCriteria Q]rqD83((
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(final DetachedCriteria detachedCriteria){ [(|v`qMv/g
return findPageByCriteria X>t3|h
9P.(^SD][z
(detachedCriteria, PaginationSupport.PAGESIZE, 0); RqLNp?V%
} 8QF2^*RZ7z
*QH[,F`I
public PaginationSupport findPageByCriteria 8bOT*^b$H
h$ Da&$uyI
(final DetachedCriteria detachedCriteria, finalint >zmzK{A=
v"RiPHLT
startIndex){ #) ]c0]p
return findPageByCriteria Uo6(|mm
DMd ,8W7a
(detachedCriteria, PaginationSupport.PAGESIZE, J?%}=_fsa
-=)-s m'
startIndex); q8sbn
} ,[`$JNc
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public PaginationSupport findPageByCriteria RtC'v";6
[M:S`{SbY
(final DetachedCriteria detachedCriteria, finalint :c7CiP
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pageSize, ntGq"
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finalint startIndex){ })[($$f/
return(PaginationSupport) ]1sNmi$T
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getHibernateTemplate().execute(new HibernateCallback(){ Q\9K2=4
publicObject doInHibernate c!Dc8=nE0m
xU}M;4kH~
(Session session)throws HibernateException { 73
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Criteria criteria = }Hy ~i
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detachedCriteria.getExecutableCriteria(session); VVuR+=.&
int totalCount = i8~r
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((Integer) criteria.setProjection(Projections.rowCount =_PvrB 2'
qC@Ar)T
()).uniqueResult()).intValue(); -$YJfQE6G
criteria.setProjection XmWlv{T+
S|K}k:v8
(null); A#DR9Eq
List items = %0XvJF)s
S LGW:
criteria.setFirstResult(startIndex).setMaxResults ?`AGF%zp
."mlSW"Wm
(pageSize).list(); ai;\@$ cq
PaginationSupport ps = 4:1)~z
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new PaginationSupport(items, totalCount, pageSize, jN/ j\x'
=;{^"#r\
startIndex); r{[OJc!
return ps; n &}s-`D
} s[AA7>]3
}, true); 1R*=.i%W
} sLns3&n2
o8z)nOTO;
public List findAllByCriteria(final q`Q}yE>9
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DetachedCriteria detachedCriteria){ \VN=Ef\E
return(List) getHibernateTemplate 7=k^M, a
2z\;Q8g){r
().execute(new HibernateCallback(){ p=gX!4,9<
publicObject doInHibernate Hwu4:^OL|
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(Session session)throws HibernateException { -BhTkoN)
Criteria criteria = s@!$='|
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detachedCriteria.getExecutableCriteria(session); U7H9/<&o
return criteria.list(); *YvRNHP
} yn~P{}68
}, true); j*zD0I]
} q;A;H)?g
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public int getCountByCriteria(final 'M/([|@
K+),?Q
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DetachedCriteria detachedCriteria){ lf$Ve
Integer count = (Integer) fKkjn4&W
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getHibernateTemplate().execute(new HibernateCallback(){ Ty+I8e]{
publicObject doInHibernate r:9gf?(&
*H2]H@QHN
(Session session)throws HibernateException { '*!L!VJ
Criteria criteria = IOEM[zhb$
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detachedCriteria.getExecutableCriteria(session); Cs1>bpY*R6
return =+oZtP-+o
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criteria.setProjection(Projections.rowCount S>f&6ZDNY(
W`L!N&fB
()).uniqueResult(); l\Xd.H" j,
} ycX{NDGs
}, true); ngyY
return count.intValue(); %l$W*.j|;
} 91d },Mq:
} 6 bO;&
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用户在web层构造查询条件detachedCriteria,和可选的 '^}+Fv<O
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <qeCso
{9'M0=
PaginationSupport的实例ps。 V#^yX%
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ps.getItems()得到已分页好的结果集 `9 [i79U
ps.getIndexes()得到分页索引的数组 'uC59X4l
ps.getTotalCount()得到总结果数 !O)qYmK]|
ps.getStartIndex()当前分页索引 >i~^TY-&
ps.getNextIndex()下一页索引 ~F[L4y!sL
ps.getPreviousIndex()上一页索引 ][:rLs
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j
_ ;fWBD:
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tXq)nfGe{
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ! OE*z $\
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 CqoG.1jJS
G{lcYP O
一下代码重构了。 N|dD!
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我把原本我的做法也提供出来供大家讨论吧: \:/Lc{*}MD
VKuAO$s$
首先,为了实现分页查询,我封装了一个Page类: xRxy|x[
java代码: Lj
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/*Created on 2005-4-14*/ aj8Rb&
package org.flyware.util.page; wNDbHR
C`K^L=8`{
/** jP=Hf=:$
* @author Joa qd6fU^)i
* J YmAn?o-
*/ GyC)EFd
publicclass Page { +5X DF
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/** imply if the page has previous page */ id,NONb\
privateboolean hasPrePage; Ge \["`;i
6/Y1 wu
/** imply if the page has next page */ p>kq+mP2bc
privateboolean hasNextPage; FFcB54ALTf
hIU(P Dl4
/** the number of every page */ Ix8$njp[
privateint everyPage; O4|2|sA
~`cwG`
'N
/** the total page number */ S!Jh2tsg`-
privateint totalPage; #R5U
@*O?6>
/** the number of current page */ yoS? s
privateint currentPage; K*vU5S
$8=@R'
/** the begin index of the records by the current 1FERmf? ?d
o0I9M?lP
query */ I:=dG[\h2
privateint beginIndex; 97`WMs
JUt7En;XE
Mi0sC24b|
/** The default constructor */ K-Mc6
public Page(){ aMwB>bt
i[nF.I5*f
} H lB]38
MXZ>"G
/** construct the page by everyPage uA~slS
Z
* @param everyPage B3
zk(RNZ
* */ :1aL
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public Page(int everyPage){ 7"2b H
this.everyPage = everyPage; ?M}S|dsmE
} l-)Bivoi
Q*ju
sm
/** The whole constructor */
9
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public Page(boolean hasPrePage, boolean hasNextPage, C"eXs#A
b{cU<;G)y.
0b-?q&*_
int everyPage, int totalPage, ;hDa@3|]34
int currentPage, int beginIndex){ GjT#%GBF
this.hasPrePage = hasPrePage; FN87^.^2S
this.hasNextPage = hasNextPage; MDO$m g
this.everyPage = everyPage; PuCc2'#
this.totalPage = totalPage; )&W**!(C
this.currentPage = currentPage; a.%LHb
this.beginIndex = beginIndex; fi%r<]@
} p{tK_ZBy]c
>fs2kha
/** #1/}3+=5B
* @return gNj7@bX~
* Returns the beginIndex. SNY (*
*/ $dg9z}D
publicint getBeginIndex(){ c:hK$C)T
return beginIndex; uO(w1Q"^
} B!S 167Op
)u} Q:`9
/** eph)=F$
* @param beginIndex Zq"7,z7
* The beginIndex to set. EU+cca|qS9
*/ "8<K'zeS8
publicvoid setBeginIndex(int beginIndex){ `DW2spd
this.beginIndex = beginIndex; hv)8K'u
} = !2NU
QwWW!8
/** &0
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* @return ~)X[(T{
* Returns the currentPage. %w}gzxN^
*/ wSXVyg{
publicint getCurrentPage(){ nb,2,H
return currentPage; 3MBN:dbQ
} |D#2GeBw1h
MQTdk*L_]
/** {7"0,2 Hb?
* @param currentPage t#wmAOW
* The currentPage to set. N$I03m
*/ 6d|q+]x_n
publicvoid setCurrentPage(int currentPage){ 5LW}h^N
this.currentPage = currentPage; ! fl4"
} dF@)M
IApT'QNM
/** >,5i60Q
* @return #/-_1H
* Returns the everyPage. `dkV_ O0
*/ [xlIG}e9
publicint getEveryPage(){ 1y"3
return everyPage; h0 |}TV^UJ
} @4GA^h
][@F
/** 5er@)p_
* @param everyPage bud&R4+
* The everyPage to set. x?,9_va]
*/ Lc2QXeo8
publicvoid setEveryPage(int everyPage){ FQsUm?ac:
this.everyPage = everyPage; vzo4g,Bj
} &Z^(y}jPr
9^ed-h
Bf
/** KG9t3<-`
* @return zc+@lJy
* Returns the hasNextPage. J%rP$O$
*/ XEH}4;C'{
publicboolean getHasNextPage(){ +Ic ~ f1zh
return hasNextPage; k5BXirB
} 3'I^lc
!u|Tu4G^
/** MmoR~~*
* @param hasNextPage PS>x,T
* The hasNextPage to set. yt0,^*t_
*/ ^>c8t_RG
publicvoid setHasNextPage(boolean hasNextPage){ @tT-JwU
this.hasNextPage = hasNextPage; hsNWqk qys
} J ++v@4Z
)0 Z! n
/** I*|P@0
* @return Wr~yK? : ]
* Returns the hasPrePage. A#@_V'a8
*/ Ub$n |xn
publicboolean getHasPrePage(){ ,J=P,](
return hasPrePage; hwnJE958L
} YlK7;yrq(
]7 GlO9
/** #@.-B,]
* @param hasPrePage !X^Ce)1K
* The hasPrePage to set. cNK)5-
U
*/ nhT(P`6
publicvoid setHasPrePage(boolean hasPrePage){ 9.OA, 6
this.hasPrePage = hasPrePage; ]/2T\w.<
} @r7:NU}
l&(l$@t
/** 3c'#6virz
* @return Returns the totalPage. 8;gXg
* 8F5|EpB9M
*/ 'xK.UI
publicint getTotalPage(){ Q(7ob}+jQ
return totalPage; @E9" Zv-$
} PO-"M)M
5p"BD'^:
/** B|=|.qp$)
* @param totalPage 0"WDH)7hJ
* The totalPage to set. 7
h=QW5
*/ #(;<-7M2
publicvoid setTotalPage(int totalPage){ v1G"3fy9
this.totalPage = totalPage; $9!D\N,}]C
} XVVD 0^ Q
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} |}&RXD
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j f~wBmd7
lTRl"`@S
jQs>`P-CM
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?,knit2x
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个PageUtil,负责对Page对象进行构造: }%!tT\8
java代码: ^V*-1r1
0?Q_@Y
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/*Created on 2005-4-14*/ _
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package org.flyware.util.page; `u'bRp
]c)_&{:V
import org.apache.commons.logging.Log; MHj,<|8Q
import org.apache.commons.logging.LogFactory; |pZUlQbb
m"2d$vro"
/** (K..k-o`.
* @author Joa E)N<lh
* 8AFczeg[[
*/ I s57F4[}
publicclass PageUtil { IND ]j72
i&Fiq&V)[
privatestaticfinal Log logger = LogFactory.getLog 9]'&RyH=#
{jKI^aC<[
(PageUtil.class); V\5 L?}
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/** =duks\)O
* Use the origin page to create a new page ,Ds.x@p
* @param page Z=S>0|`R
* @param totalRecords ;az5ZsvN
D
* @return xG2+(f#C1
*/ _D7 ]-3uC!
publicstatic Page createPage(Page page, int m#e3%150{
{D&9UZm
totalRecords){ UL@9W6
return createPage(page.getEveryPage(), s,]%dG!
v;1F[?@3Y
page.getCurrentPage(), totalRecords); kJ:F *34e=
} U/{6%
Qy
Zi\['2CG
/**
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* the basic page utils not including exception ?DV5y|}pj
LtgXShp_!
handler ,,L2(N
* @param everyPage
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* @param currentPage tB7}|jC
* @param totalRecords d(`AXyw
* @return page '])2k@o@
*/ c"tJld5F_
publicstatic Page createPage(int everyPage, int vdDludEv
sJx+8
-
currentPage, int totalRecords){ &[mZD,
everyPage = getEveryPage(everyPage); %qf V+^
currentPage = getCurrentPage(currentPage); ^L4Qbc(vJ
int beginIndex = getBeginIndex(everyPage, a,t``'c;
y@V_g'
currentPage); nz.{P@[Qk
int totalPage = getTotalPage(everyPage, 13'vH]S$M
$
<8~k^
totalRecords); OFkNl}D
boolean hasNextPage = hasNextPage(currentPage, YcX/{L[9o
-Y 9SngxM
totalPage); V%0I%\0Y
boolean hasPrePage = hasPrePage(currentPage); IeX^4rc(
G9P!_72
returnnew Page(hasPrePage, hasNextPage, '\#EIG
everyPage, totalPage, ,Tagj`@bHc
currentPage, oB1>x^
gR^>3n'
beginIndex); ~ (On|h
} LjFqZrH
Z#l%r0(o
privatestaticint getEveryPage(int everyPage){ T\s)le
return everyPage == 0 ? 10 : everyPage; E\8
} zhI#f0c
6M.;@t,Y
privatestaticint getCurrentPage(int currentPage){ YV4#%I!<
return currentPage == 0 ? 1 : currentPage; (6p]ZY
} SAV%4
qo6y %[
privatestaticint getBeginIndex(int everyPage, int zQ6p+R7D
0H_!Kg
currentPage){ v60^4K>
return(currentPage - 1) * everyPage; 9i5,2~
} rX7QbAB
s?Uh| BfB
privatestaticint getTotalPage(int everyPage, int r`S< A;
A=zPLq{Sb
totalRecords){ )2q~u%9n
int totalPage = 0; AdZ;j6#
s pLZ2]A
if(totalRecords % everyPage == 0) |WryBzZ>on
totalPage = totalRecords / everyPage; -~" :f8
else nR>r2wMk@
totalPage = totalRecords / everyPage + 1 ; H1"q
UM*jKi2]"
return totalPage; <AlZ]~Yct
} #3=P4FUz.
?Ucu#UO
privatestaticboolean hasPrePage(int currentPage){ HBE.F&C88
return currentPage == 1 ? false : true; AGP("U'u
} h_d +$W5
]'~vI/p
privatestaticboolean hasNextPage(int currentPage, c)md
$/1c= Y@
int totalPage){ f&,{XZ
return currentPage == totalPage || totalPage == 60=m
{4aWR><
0 ? false : true;
}}<Z,/O
} BElJB&I
DD9 ?V}Yx
nfW&1a
} Q^K "8 ;
]{~NO{0@Y
[[~w0G~1
g42)7
`cQo0{xK
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 F
09DV<j
Q zZ;Ob]'
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Z4$cyL'$P
[
=x s4=
做法如下: Rv,JU6>i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 I
V%VU
)Rat0$6
的信息,和一个结果集List: 8n BL\{'B[
java代码: mV73
\P6K
I]"96'|N
p,pR!qC>
/*Created on 2005-6-13*/ @4(k(
package com.adt.bo; gG%V 9eOQ
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import java.util.List; [OTJV pC
b*fgv9Kh'
import org.flyware.util.page.Page; [+*$\
/WV7gO&L1
/** >R{qESmP=
* @author Joa 1
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*/ f=!PllxL:
publicclass Result { y|&}.~U[
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private Page page; %B5r"=oO
'evj,zFhW
private List content; H+}"q$
@=]~\[e\
/** ~1m2#>
* The default constructor R8L_J6Kpa
*/ uJR%0 E7!
public Result(){ U`Jy!x2m
super(); .O*bILU
} )4?x5#
!}\4utHY
/** /<CSVJ_r
* The constructor using fields @\oz4^
* v]%WH~>
* @param page *?+V65~dW
* @param content Giq=*D+
*/ DcIvhB p
public Result(Page page, List content){ to8X=80-3
this.page = page; JxLf?ad.
this.content = content; 04%S+y.6&Y
} &|%6|u9
]`g<w#
/** L{l6Dd43q
* @return Returns the content. ~A<H9Bw
*/ xR"M*%{@0
publicList getContent(){ =Cv/Y%DN
return content; o]{uc,
} PN~@
qjJBcu_C'S
/** }pkj:NT
* @return Returns the page. 3ZTE<zRQ
*/
%dErnc$
public Page getPage(){ Iu~\L0R427
return page; zL5d0_E9
} 8,O33qwH
%xlqF<
/** v{i7h|e
* @param content =.|J!x
* The content to set. $rXh0g
*/ r[.>P$U
public void setContent(List content){ obK*rdg,
this.content = content; 9p 4"r^
} }
B396X
'^%~JyU
/** )CI1;
* @param page ~9F ,%
* The page to set. KtS)'jf
*/ d|Gl`BG
publicvoid setPage(Page page){ 5dx&Qu'}ZS
this.page = page; Fg$3N5*
} o!Ev;'D
} juAMAplf
dX8hpQ
#B'aU#$u
+ SZYg[
'B83m#HR#
2. 编写业务逻辑接口,并实现它(UserManager, q;5i4|
B:"THN^
UserManagerImpl) DlMe5=n-u
java代码: dk
QaM@
@4%L36k
ULc`~]
/*Created on 2005-7-15*/ J68j=`Y
package com.adt.service; I"AYWo?
Ub0/r$]DK
import net.sf.hibernate.HibernateException; D7]#Xk2
_$<Gyz*
import org.flyware.util.page.Page; U%7i=Z{^Ks
5`~mmAUk;`
import com.adt.bo.Result; 8$|8`;I(
""O"
/** )Fd
HV;K
* @author Joa rQ4*k'lA:
*/ 4fh^[\
publicinterface UserManager { 0s#vwK13
E'1+ Yq
public Result listUser(Page page)throws {)- .xG
[w
-{r+[
HibernateException; ka\OJ7u
s57N) 0kP
} sGY_{CZ:
k>}g\a,
rA0,`}8\
N-lGa@ j
6*9}4`
java代码: DfJ2PX}q
xy+QbDT
d{et8N
/*Created on 2005-7-15*/ q,<[hBri-
package com.adt.service.impl; O#nR>1h
_ 7oV<
import java.util.List; k<w(i
k1bi
)T907I|
import net.sf.hibernate.HibernateException; l=`L7| ^/d
@vgG1w
import org.flyware.util.page.Page; uBg 8h{>
import org.flyware.util.page.PageUtil; [MX;,%;;
^/wfXm
import com.adt.bo.Result; s)voII&
import com.adt.dao.UserDAO; aI
zv
import com.adt.exception.ObjectNotFoundException; j^`X~gE
import com.adt.service.UserManager; F}J-gZl
/9Q3iV$I]
/** nM=e]qH
* @author Joa Y**|N8e
*/ QH4wUU3X
publicclass UserManagerImpl implements UserManager { a\kb^D=T
HQ!Xj.y
private UserDAO userDAO; puSLqouTM
fQWIw
/** B;Nl~Y| \
* @param userDAO The userDAO to set. ^Yr0@pE
*/ TAL/a*7\
publicvoid setUserDAO(UserDAO userDAO){ vv6$>SU
this.userDAO = userDAO; [\)oo
} sKLX [l
#gQF'
/* (non-Javadoc) rh2LGuo4m
* @see com.adt.service.UserManager#listUser k'`m97B
hovGQHg
(org.flyware.util.page.Page) .F&9.#>
*/ 5OM?3M
public Result listUser(Page page)throws G@!z$
MgnM,95
HibernateException, ObjectNotFoundException { 2.}R
int totalRecords = userDAO.getUserCount(); sK$wN4k
if(totalRecords == 0) CR4rDh8z a
throw new ObjectNotFoundException ?tf&pgo
78n}rT%k1
("userNotExist"); 3HG;!D~m;
page = PageUtil.createPage(page, totalRecords); ;N+$2w
List users = userDAO.getUserByPage(page); dYFzye
returnnew Result(page, users); @$Qof1j'%
} mOll5O7VW
G"
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} (A k\Lm
,zcQS-e2
lw8"'0
m:tiY
[c>W
b yg0.+e0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Gtv,Izt
RR1A65B
询,接下来编写UserDAO的代码: J}spiVM
3. UserDAO 和 UserDAOImpl: <Pqv;WI|R
java代码: Pvo#pY^dXX
h>S[^
-,
7&}P{<}o^
/*Created on 2005-7-15*/ iY[+Ywh
package com.adt.dao; i;\s.wrzH
WiNT;v[
import java.util.List; PL0`d`TI
B,$l4m4
import org.flyware.util.page.Page; &znH!AQ0
HgBJf~q~U
import net.sf.hibernate.HibernateException; n[xkSF^)
)\/
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/** yT OyDm-
* @author Joa XR# ;{p+b
*/ a+41|)pt
publicinterface UserDAO extends BaseDAO { /%x7+Rl\-^
1ZJ4*b n
publicList getUserByName(String name)throws ]rd/;kg.S
4C_c\;d
HibernateException; huFz97?y(
9~AWn g
publicint getUserCount()throws HibernateException; /
YiQ\
_68BP)nz>.
publicList getUserByPage(Page page)throws iCG`3(xL
=?@Q-(bp
HibernateException; khd5 Cf[
'aJgLws*w
} Lrz3
`hh9"Ws%
XaI;2fMGI
tgFJZA
/4S;QEv
java代码: W+>wu%[L
8@K^|xeQ
q?{}3 dPC
/*Created on 2005-7-15*/ >X}{BDMb.
package com.adt.dao.impl; u/^|XOy
)-P!Ae_.v
import java.util.List; #5CI)4x0!
Go\VfLL w
import org.flyware.util.page.Page; d{+(Lpj^
vL_zvXA
import net.sf.hibernate.HibernateException; M.%shrJ/
import net.sf.hibernate.Query; ^t.W|teD
F%.xuL W
import com.adt.dao.UserDAO; {gF0Xm%
<dR,'
/** "Tbnxx]J
* @author Joa 9V!-ZG
*/ tn<6:@T
public class UserDAOImpl extends BaseDAOHibernateImpl M8W# io
j\)H
implements UserDAO { DQ!J!ltQ
3><u*0qe%I
/* (non-Javadoc) 9w~cvlv[
* @see com.adt.dao.UserDAO#getUserByName I=dGq;Jaz
?qHF}k|
(java.lang.String) e$l6gY
*/ LVtu*k
publicList getUserByName(String name)throws 9Ld9N;rWm#
<bmLy_":
HibernateException { hq_~^/v\
String querySentence = "FROM user in class )@7DsV/M
ija:H'j
com.adt.po.User WHERE user.name=:name"; s${_K* g6
Query query = getSession().createQuery =G>(~+EA
&~~s6
(querySentence); -e>|kPfv!
query.setParameter("name", name); Agy
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return query.list(); ziL^M"~2
} sOC&Q&eg
x'`"iZO.t
/* (non-Javadoc) 4,1oU|fz
* @see com.adt.dao.UserDAO#getUserCount() 1M5 -pZ[D
*/ Y(i?M~3\t
publicint getUserCount()throws HibernateException { r'aY2n^O
int count = 0; w+UV"\!G)Q
String querySentence = "SELECT count(*) FROM
IsYP0(L
3B9nP._
user in class com.adt.po.User"; YB!!/ SX4
Query query = getSession().createQuery (!zM\sF
Z!\@%`0$
(querySentence); (aKZ5>>cN
count = ((Integer)query.iterate().next `F1dyf!p<
oh\,OW
()).intValue(); -CBD|fo[h
return count; !oMt_k X
} uEd,rEB>
MV936
/* (non-Javadoc) I-:`cON=G
* @see com.adt.dao.UserDAO#getUserByPage Vewzo1G2
y4F^|kS) [
(org.flyware.util.page.Page) gg]~2f
*/ -J$g(sikt
publicList getUserByPage(Page page)throws 7kz-V.
960qvz!
HibernateException { ?SX_gYe9
String querySentence = "FROM user in class 1r4,XSk
981!2*
com.adt.po.User"; EF;,Gjh5p
Query query = getSession().createQuery 31XU7A
1D1b"o
(querySentence); N/{?7sG&
query.setFirstResult(page.getBeginIndex()) -<oZ)OfU
.setMaxResults(page.getEveryPage()); 7:o+iP4 6
return query.list(); _Y-$}KwY!
} rx:lKoOnB
]h@{6N'oNS
}
KOSyh<&
0|C[-ppr
7%CIt?Z%
`"Dy%&U
Ak=UtDN[
至此,一个完整的分页程序完成。前台的只需要调用
5-'vB
L>nO:`>h
userManager.listUser(page)即可得到一个Page对象和结果集对象 #v8Cy|I
60PYCqWc
的综合体,而传入的参数page对象则可以由前台传入,如果用 BX$hAQ(6Q
`Cj,HI_/*
webwork,甚至可以直接在配置文件中指定。 ryEvmWYu
wo(j}O-
下面给出一个webwork调用示例: Nmf#`+7gCI
java代码: <nA3Sd"QfV
AQ}l%
3wNN<R
/*Created on 2005-6-17*/ \Da~p9T&
package com.adt.action.user; SJ(9rhB5*.
{HuLuP0t
import java.util.List; @,vv\M0)p
MZ^Ch
import org.apache.commons.logging.Log; E& ]_U$
import org.apache.commons.logging.LogFactory; ^
wQcB
import org.flyware.util.page.Page; Q-Y@)Mf~?0
\UQ],+H
import com.adt.bo.Result; LW?2}`+
import com.adt.service.UserService; /nM*ljfB\
import com.opensymphony.xwork.Action; 4~WlP,,M
jr1Se9u D
/** b-b;7a\N
* @author Joa }}s)
+d
*/ +~:0Dxv W
publicclass ListUser implementsAction{ N7B}O*;
AzX(~Qc
privatestaticfinal Log logger = LogFactory.getLog `q1}6U/k
?M<|r11}
(ListUser.class); uN&M\(
=+Tsknq
private UserService userService; )`RZkCe
K!b>TICa:
private Page page; ]}_,U!`8
"0Y&~q[=
privateList users; "GB UQ}
+2(PcJR~
/* YD+QX@
* (non-Javadoc) d.1Q~&`
* g[<uwknf
* @see com.opensymphony.xwork.Action#execute() ke</x+\F
*/ faJ8zX
publicString execute()throwsException{ Z{16S=0
Result result = userService.listUser(page); bl9E&B/
page = result.getPage(); G[B*TM6$
users = result.getContent(); Faw. GU
return SUCCESS; Q
}8C
} nTQ (JDf
&`5 :GLV
/** "U{mMd!9L
* @return Returns the page. qZc)Sa.S
*/ Ot"(uW4$[
public Page getPage(){ dK7 ^
return page; 8Nv-/VQ/b
} ,dq`EsHg`M
{&b-}f"m
/** 7dx4~dF
* @return Returns the users. ],#ZPUn
*/ m&{rBz0
publicList getUsers(){ (BhL/A 4
return users; Ut=0~x.=<
} M,Po54u
xKisL=l6Y
/** <#!8?o&i
* @param page ,P1G?,y
* The page to set. kfIbgya
*/ &A#90xzF
publicvoid setPage(Page page){ :'TX"E!
this.page = page; @~Rk^/0
} ?##y`.+O
J]_)gb'1BR
/** K
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* @param users 0c{Gr 0[>
* The users to set. p@`4 Qz
*/ Z 'Zd[."s
publicvoid setUsers(List users){ !FO:^P
this.users = users; (jt*u (C&Y
} O/'f$ Zj36
Zr~"\llk
/** fG^7@Jw:G
* @param userService ~MD><w>
* The userService to set. lp3(&p<:
*/ @)8NI[=6O
publicvoid setUserService(UserService userService){ ROcY'-
this.userService = userService; VdYOm
} D DZTqsws
} qRWJ-T:!F
047*gn.b
(p'/p
0!)U *+j,
i,^>uf
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, LjX&',
N>h]mX6
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 Gf!t< =T
LH1BZ(5g
么只需要: +X{cN5Y K
java代码: d;IJ0xB+by
F12S(5Z0%
6i55J a
<?xml version="1.0"?> 4h[2C6
\+`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork WIhIEU7 /
_q2`m
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 3Bu D/bs
=2Pz$q*ub
1.0.dtd"> MX%|hIOpr
*s
1D\/H
<xwork> ,<IL*=a
pvK \fSr
<package name="user" extends="webwork- 1j_aH#Fz:
}C9VTJs|
interceptors"> F^J&g%ql
0fEZD$
<!-- The default interceptor stack name xow6@M,
dpl"}+
--> Vu^Q4Z
<default-interceptor-ref ajg7xF{l)
|rG8E;>
name="myDefaultWebStack"/> UzP@{?
:"h
Pg]'
<action name="listUser" m(Pz7U.Q
LD7? .
class="com.adt.action.user.ListUser"> w;g)Iy6x
<param O p!
<<~lV5
name="page.everyPage">10</param> ^*j[&:d
<result j58Dki->.
T(t
<Ay?c
name="success">/user/user_list.jsp</result> [0(
E>vm
</action> {3_F fsg`
j@!BOL~?
</package> c9>8IW
E0WrpGZ
</xwork> u k>q\j
T=iZ9w
7l4InR]
|~1rKzZwF
}Etd#">
aH~x7N6!
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 Z &ua,:5
T% jjs
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。 e%5'(V-y,
\ZmFH8=|f
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^Hy)<P
?kG#qt]Q5
&z1|
^loF#d=s
U[H+87zg
我写的一个用于分页的类,用了泛型了,hoho ~50y-
BdRE*9.0
java代码: _AsHw
o>QFdx
DT1i2!
package com.intokr.util; Gff[c%I
hA&j?{
import java.util.List; Oa3=+_C~$1
I*`=[nR
/** a`GN@
8
* 用于分页的类<br> 5r2ctde)Y
* 可以用于传递查询的结果也可以用于传送查询的参数<br> _tWfb}6;Zb
* )SlUQ7f>
* @version 0.01 8/kx 3
* @author cheng HT1dvC$COo
*/ LmT[N@>"
public class Paginator<E> { 8{U]ATx'(
privateint count = 0; // 总记录数 D+@/x{wX2
privateint p = 1; // 页编号 7o 83|s.Bm
privateint num = 20; // 每页的记录数 W6!4Qyn
privateList<E> results = null; // 结果 U- U V<}
2rE~V.)%
/** H8Z Z@@ qm
* 结果总数
!EyGJa[i
*/ 8M(|{~~3:
publicint getCount(){ is_dPc
return count; $
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} A(!ZZ9Wc
nP3;<*T P0
publicvoid setCount(int count){ /d]V{I~6
this.count = count; 0ga1Yr]
}
DFZ:.6p
Q,`2DHhK
/** olQ8s*
* 本结果所在的页码,从1开始 W>
-E.#!_
* 7.Kjg_N#Tr
* @return Returns the pageNo. e*'|iuDrY
*/ }i/2XmA )
publicint getP(){ ^|hRu{QW
return p; KTAe~y
} |
9\7xT
yADN_
/** (fI&("; t
* if(p<=0) p=1 #B.w7y5*
* Osvz 3UMY3
* @param p (^s_w03
*/ PU/Br;2A
publicvoid setP(int p){ "3KSmb
if(p <= 0) ^5'/ }iR2N
p = 1; R4rm>zisVX
this.p = p; O|7{%5h
} Ns(L1'9=
Vlxb<$5Nh
/** yPxG`w'
* 每页记录数量 bQ\ -6dOtv
*/ Cx3m\
\c
publicint getNum(){ YO!7D5rV #
return num; j[=_1~u}
} y:6'&`L
>a`zkl
/** :Kc0ak)<n
* if(num<1) num=1 ;h(;(
*/ .0*CT:1=0
publicvoid setNum(int num){ GPqB\bxb'
if(num < 1) ~RLx;
num = 1; ))+98iU1s
this.num = num; <[B[
} =rO>b{,hs
o:Os_NaD
/** {@F["YPxy
* 获得总页数 5`{;hFl
*/ rj f=qh5s
publicint getPageNum(){ BnnUUaE
return(count - 1) / num + 1; q?]@' ^:;
} )D-.7m.v]
_>)"+z^r
/** cZX&itVc:
* 获得本页的开始编号,为 (p-1)*num+1 bZlLivi
*/ 1S.e5{
publicint getStart(){ 2Q'XB
return(p - 1) * num + 1; 0gb]Kj x
} P)j9\ muc
z hm!sMlO
/** MfpWow-#{
* @return Returns the results. C.e|VzQa
*/ %LZM5Z^
publicList<E> getResults(){ Xgth|C}k
return results; iYQy#kO
} YU0HySP:
'<W,-i
public void setResults(List<E> results){ HF=C8ZtlL
this.results = results; 1*,~ 1!>
} EKS<s82hF&
~TK^aM
public String toString(){ l:Xf(TLa
StringBuilder buff = new StringBuilder <Ibr.L]
OVo
(); ~aR='\<