Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~|lIC !q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +l?; )
9`"DFFSMS
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 0mexF@
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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 S#8>ZwQ
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。 ~]WVG@-
0oU=RbC
分页支持类: 5PZN^\^
6^#uLp>
java代码: `cr(wdvI
[pgZbOIN37
] hE="z=n
package com.javaeye.common.util; @Bs0Avj.
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import java.util.List; otr>3a*'
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publicclass PaginationSupport { "tu*YNP\Q
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publicfinalstaticint PAGESIZE = 30; ]Kdet"+
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privateint pageSize = PAGESIZE; op7FZHs
UG2w 1xqHw
privateList items; vR>o}%`
z`$J_Cj Y
privateint totalCount; H4<Nnd\
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privateint[] indexes = newint[0]; ;sPzOS9
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privateint startIndex = 0; K: r\{#9
8`v$liH
public PaginationSupport(List items, int H?yE3w
bAF )Bli
totalCount){ Ec]|p6a3
setPageSize(PAGESIZE); o6}n8U}bk
setTotalCount(totalCount); ~}% ~oT
setItems(items); x5Zrz<Y$w
setStartIndex(0); hu5!ev2
} A^Cj1:,
2KI!af[I
public PaginationSupport(List items, int m)&znLA
SEF6B45}1
totalCount, int startIndex){ `UzVS>]l[+
setPageSize(PAGESIZE);
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setTotalCount(totalCount); 5bX6#5uP1
setItems(items); ii4B?E
setStartIndex(startIndex); Mkv|TyC
} X-JV'KE}^z
w1|Hy2D`0
public PaginationSupport(List items, int %_gho
|M5-5)
totalCount, int pageSize, int startIndex){ Mm=Mz
setPageSize(pageSize); j+^L~, S
setTotalCount(totalCount); )\ 0F7Z
setItems(items); c[cAUsk i
setStartIndex(startIndex); 6)*xU|fU
} $=aI"(3&
(P@Y36j>N
publicList getItems(){ or?%-)
return items; 85 ]SC$
} :tGYs8UK
g]$
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publicvoid setItems(List items){ <{ru|-9
this.items = items; >+9JD%]x]
} d"THt}
Q9>U1]\
publicint getPageSize(){ J7&DR^.Sw
return pageSize; V@ :20m
} +=3CL2{An
9$l>\.6
publicvoid setPageSize(int pageSize){ 6yIvaY$KR
this.pageSize = pageSize; n2ndjE$
} 0SV \{]2
[Ot,q/hBJ
publicint getTotalCount(){ 3]LN;s]ac
return totalCount; B)=~8wsI:Z
} ($!KzxF3
M##';x0
publicvoid setTotalCount(int totalCount){ e!x6bR9EZ
if(totalCount > 0){ uJow7-FD
this.totalCount = totalCount; sbsu(Sz+
int count = totalCount / V1bh|+o9
|V&G81sM
pageSize; 1dG06<!
if(totalCount % pageSize > 0) Ax<\jW<
count++; Z<z;L<tJ 9
indexes = newint[count]; VOgi7\
for(int i = 0; i < count; i++){ OtUrGQP
indexes = pageSize * eaZQ2
7'w0
i; Q/^A #l[
} _p}xZD\?,
}else{
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this.totalCount = 0; x:z0EYL
} WjMRH+
} Ewo~9
4{
1]OSWCEm*[
publicint[] getIndexes(){ e<\<,)9@/
return indexes; /Jlv"R1,
} eti`O
t/p $
publicvoid setIndexes(int[] indexes){ 1~5trsB+5
this.indexes = indexes; p2pAvlNoF
} JWHSnu!
r|R7-HI
publicint getStartIndex(){ ;#anZC;
return startIndex; 8L{u}|{
} h/ep`-YaH
D-ADv3E,
publicvoid setStartIndex(int startIndex){ I4e+$bU3
if(totalCount <= 0) ^^?q$1k6r*
this.startIndex = 0; l},NcPL`
elseif(startIndex >= totalCount) vK$^y^
this.startIndex = indexes 2VgP
j
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[indexes.length - 1]; (.X]F_*sc
elseif(startIndex < 0) ,E*R,'w
this.startIndex = 0; le
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else{ v%91k
this.startIndex = indexes Jh@_9/?
g1[&c+=U`P
[startIndex / pageSize]; 9K"JYJ
q2
} }STYG`
} l[Z)@bC1
$&{IKP)u
publicint getNextIndex(){ 80hme+e
int nextIndex = getStartIndex() + tL(B pL'
H%i>L?J2 /
pageSize; yI8tH!
if(nextIndex >= totalCount) LI
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return getStartIndex(); }DIF%}UK\
else =_d%=m
return nextIndex; ClUSrSp
} >mm'-P
hx!7w}[A
publicint getPreviousIndex(){ (4+1lOd
int previousIndex = getStartIndex() - I$jvXl=$
ijYvqZ_
pageSize; .ER 98
if(previousIndex < 0) M?@pN<|
return0; _m'ysCjA
else By((,QpB
return previousIndex; q-AN[_@
} $k0H9_
:`W|hE^
} zVaCXNcbo
L\ j:
wGLF%;rRe4
Dkw7]9Qm
抽象业务类 +=fKT,-*G!
java代码: i/qTFQst
_
tYe:z:7l?<
!]b@RUU
/** 'gTmH [be
* Created on 2005-7-12 NPJ.+ph
*/ (6qsKX
package com.javaeye.common.business; ;e{5)@h$
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import java.io.Serializable; 7_)|I?
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import java.util.List; ZF{~ih*^u
}T(z4P3
import org.hibernate.Criteria; G\~^&BAC
import org.hibernate.HibernateException; *xH\)|3,
import org.hibernate.Session; 8vD3=yK%^
import org.hibernate.criterion.DetachedCriteria; V2 `>
]/|
import org.hibernate.criterion.Projections; n9oR)&:o
import b|?;h21rG
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org.springframework.orm.hibernate3.HibernateCallback; w~@[r4W
import ycpE=fso'
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org.springframework.orm.hibernate3.support.HibernateDaoS Q,e*#oK3$
WZ~> BM
upport; fI:H8
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import com.javaeye.common.util.PaginationSupport; Ps>&"k$T
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public abstract class AbstractManager extends |*\C{b
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HibernateDaoSupport { 0HibY[_PbD
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privateboolean cacheQueries = false; u{C)qb5Pu
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privateString queryCacheRegion; bZ5n,KQA5
3%
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publicvoid setCacheQueries(boolean XB/'u39
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cacheQueries){ q=0 pQ1>
this.cacheQueries = cacheQueries; ,"G\f1
} m|4LbWz
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publicvoid setQueryCacheRegion(String eyB_l.U7
F(4yS2h(
queryCacheRegion){ rsxRk7s@
this.queryCacheRegion = 0m=(W^c
uiMIz?+
queryCacheRegion; =5s$qb?#
} Q[_Ni15
J/kH%_ >Ir
publicvoid save(finalObject entity){ w}k B6o]
getHibernateTemplate().save(entity); ?r3e*qJGn
} "c
Pz|~
14l; *
publicvoid persist(finalObject entity){ yT:!%\F9
getHibernateTemplate().save(entity); K51fC4'{
} RVF F6N^
R^tcr)(
publicvoid update(finalObject entity){ /hci\-8N~
getHibernateTemplate().update(entity); ?5~!i9pY
} s]x2DH+_
9d\N[[Vu]R
publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); 0yQe5i}
} g
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(02g#A`
publicObject load(finalClass entity, EfSMFPM
yN:>!SQ
finalSerializable id){ </ZHa:=7
return getHibernateTemplate().load 9dYOH)f
q/'MS[C
(entity, id); Au=kSSB
} yJ J8"s~i
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publicObject get(finalClass entity, A- 0m8<
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finalSerializable id){ /Ynt<S9"
return getHibernateTemplate().get UK:M:9
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(entity, id); eT\p-4b
} l ?/gWD^
vnZ/tF
publicList findAll(finalClass entity){ (`mOB6j
return getHibernateTemplate().find("from Pz
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7'UWRRsxUF
" + entity.getName()); sZm^&h;
} 4vGbG:x
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publicList findByNamedQuery(finalString qKs7WBRJy
2'dG7lLu4
namedQuery){ FB!z#Eim
return getHibernateTemplate va+m9R0
>fwlg-
().findByNamedQuery(namedQuery); /cY[at|p
} G>j"cj
+V89J!7
publicList findByNamedQuery(finalString query, n|Ma&qs
gTD%4V
finalObject parameter){ STRyW Ml
return getHibernateTemplate >I:9'"`
Esa6hU#
().findByNamedQuery(query, parameter); Tvrc%L(]
} P.1Qc)m4
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publicList findByNamedQuery(finalString query, T~|PU{
;]u1~
finalObject[] parameters){ ds')PIj
return getHibernateTemplate d-i&k(M
{4)5]62>u
().findByNamedQuery(query, parameters); :z124Zf
} |vT=Nnu
vT}pbOTh
publicList find(finalString query){ )w@y(;WJ
return getHibernateTemplate().find qIk
)'!Vk
y|LXDq4Wj
(query); 6d(b'S^
} 5Wl,J _<F
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publicList find(finalString query, finalObject KK .cDAR
s9kTuhoK
parameter){ `|NevpXY1
return getHibernateTemplate().find "mG!L$
z22N7W=7
(query, parameter); X)Ocn`|
} ~Gwas0eNa
`F@f?*s:
public PaginationSupport findPageByCriteria N~0$x,bR
GZ.?MnG
(final DetachedCriteria detachedCriteria){ $q.p$JQ:
return findPageByCriteria Q.uR<C6)v
ZS|Z98
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,Zr YJ<
} WVsKrFZT
uk1v7#p
public PaginationSupport findPageByCriteria "
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8Q)y%7{6
(final DetachedCriteria detachedCriteria, finalint #C'o'%!(
Q0_M-^~WT
startIndex){ !zF4 G,W
return findPageByCriteria UU-v;_oP
}v,W-gA
(detachedCriteria, PaginationSupport.PAGESIZE, yqC+P
WMRYT"J?N]
startIndex); 8UlB~fVg
} YD dLDE
JO]`LF]
public PaginationSupport findPageByCriteria ByC1I.B`
WJBW: 2=;
(final DetachedCriteria detachedCriteria, finalint J>/Ci\OB
OcLg3.:L
pageSize, upZYv~Sa
finalint startIndex){ / *Ou$
return(PaginationSupport) +q4W0
1\=pPys)
getHibernateTemplate().execute(new HibernateCallback(){ R20a(4m
publicObject doInHibernate `W
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@m }rQT
(Session session)throws HibernateException { 5IwX\
Criteria criteria = *yL|}
$Cut
detachedCriteria.getExecutableCriteria(session); ]5aux
>.n
int totalCount = hVROzGZk
}u38:(^`ai
((Integer) criteria.setProjection(Projections.rowCount X*43!\
/QM0.{Ypl
()).uniqueResult()).intValue(); 8Q#t\$RY
criteria.setProjection n">?LN-DC
bEEJV F0
(null); g%Th_= qy
List items = F%Ro98?{
_+0uju?o}
criteria.setFirstResult(startIndex).setMaxResults fbi H
".Tf<F
(pageSize).list(); "`y W]v
PaginationSupport ps =
m,xy4
,dGFX]P
new PaginationSupport(items, totalCount, pageSize, pQ 4
%]Api
|% la
startIndex); eYnLZ&H5O
return ps; }A)^XZ/
} +5N^TnBtBL
}, true); KzxW?Ji$S
} Hz8Jgp
rjhs?
public List findAllByCriteria(final 9F-ViDI.
Qu,)wfp~
DetachedCriteria detachedCriteria){ hqwz~Ky}
return(List) getHibernateTemplate 3ZT/>a>@
0e[ tKn(
().execute(new HibernateCallback(){ 5)/4)0
publicObject doInHibernate c"oQ/x
\=
)[
(Session session)throws HibernateException { (\[jf39e
Criteria criteria = Y9\]3Kno
GN}9$:
detachedCriteria.getExecutableCriteria(session); /It.>1~2@
return criteria.list(); FE^?U%:u@
} D0,oml
}, true); =rs=8Ty?S
} @k#z&@b
m
bB\~n
public int getCountByCriteria(final l7=$4As/hI
oj,Vi-T Z
DetachedCriteria detachedCriteria){ -wG[>Y
Integer count = (Integer) ^ mQ;CMV
4#'^\5
getHibernateTemplate().execute(new HibernateCallback(){ r!-L`GUm
publicObject doInHibernate Ugee?;]lu
^5^
zo~^o
(Session session)throws HibernateException { W! 5Blo
Criteria criteria = )%nt61P\W
1.ugXD
detachedCriteria.getExecutableCriteria(session); FW6E)df
return f%(e,KgW=
X(0:zb,#G*
criteria.setProjection(Projections.rowCount h}c6+@w&-
@$N*lrM2
()).uniqueResult(); o
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} ! X#3w-K
}, true); ijR*5#5h
return count.intValue(); &Pn%zfmMN
} Bm2}\KOI
} Kuzy&NI^w
&6~ncQWu
&].1[&M]
=Un 6|]
&<[]X@ bY
qjdahVY
用户在web层构造查询条件detachedCriteria,和可选的 &p(*i@Ms
qH}62DP3
startIndex,调用业务bean的相应findByCriteria方法,返回一个 R`<{W(J;r
$`+~QR!h
PaginationSupport的实例ps。 F".IB^}$
joSr,'x
ps.getItems()得到已分页好的结果集 7\|NYT4
ps.getIndexes()得到分页索引的数组 GoZJDE3
ps.getTotalCount()得到总结果数 JUUF^/J
ps.getStartIndex()当前分页索引 Qnu&GBM
ps.getNextIndex()下一页索引 c] :J/'vc
ps.getPreviousIndex()上一页索引 "S:NU.c?
LTlC}3c28f
RQ$o'U9A
SE7 (+r
d}6AHS[
rym\5
`)
L_CEY
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XxrO:$
NVM2\fs
,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 @'G ( k;
(B?xq1Q
一下代码重构了。 ?X5glDZ$
SieV%T0t1
我把原本我的做法也提供出来供大家讨论吧: 13NS*%~7[
pC?1gc1G
首先,为了实现分页查询,我封装了一个Page类: 2L{:H
java代码: ^.$r1/U
@kgpq
JOoLHZQ1v
/*Created on 2005-4-14*/ ;*$8iwBQ_
package org.flyware.util.page; ef1N#z%gt
crOtQ
/** <@;xV_`X+
* @author Joa d .lu
* ZkVvL4yIK
*/ -uY:2
publicclass Page { Z ysUz
)LS+M_
/** imply if the page has previous page */ 1k70>RQ&69
privateboolean hasPrePage; $>*/']>
N*4IxY'vX/
/** imply if the page has next page */ uq1(yyWp(
privateboolean hasNextPage; }A&Xxh!Fwo
J&0wl]w|O%
/** the number of every page */ Ga/\kO)x_
privateint everyPage; K=^_Ndz
AK\g-]8
/** the total page number */ _ZE$\5>-
privateint totalPage; E9+O\"e9
yl]Cm?8
/** the number of current page */ x_^OS"h-
privateint currentPage; 0 6v5/Xf
68G] a N3
/** the begin index of the records by the current 3@WI*PMc
LW8{a&
query */ MxvxY,~{0
privateint beginIndex; +sq,!6#G
>C d&K9H
]Pl6:FB8%@
/** The default constructor */ Fl|&eO,e
public Page(){ ?+JxQlVDt-
EO!cv,[a
} 9g,L1 W*
-,CndRKx
/** construct the page by everyPage {]^%?]e
* @param everyPage v lnUN
* */ $;j6*,H
public Page(int everyPage){ LYo7?rp
this.everyPage = everyPage; oDiv9jm
} lNp:2P
kQiW 5
/** The whole constructor */ V?=zuB?'
public Page(boolean hasPrePage, boolean hasNextPage, dCJR,},\f
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#K
c3 ]^f6)?
int everyPage, int totalPage, aRb:.\ \zc
int currentPage, int beginIndex){ vWfef~}~
this.hasPrePage = hasPrePage; 3<Y;mA=hw
this.hasNextPage = hasNextPage; YyBq+6nq5
this.everyPage = everyPage; u KdX4
this.totalPage = totalPage; T{J`t*Ym
this.currentPage = currentPage; )RKhEm%Vr2
this.beginIndex = beginIndex; 2o7C2)YT$
} )o(F*v
|N3CoB
/** g,]5&C T3v
* @return -VT?/=Y
s
* Returns the beginIndex. zpQ/E
*/ fi@+swfc
publicint getBeginIndex(){ *:\9T#h
return beginIndex; `pS)qx.a
} H
{Wpf9_
K
) x O_
/** G6ES]
* @param beginIndex p:n^c5
* The beginIndex to set. &ZFAUE,[
*/ /M
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publicvoid setBeginIndex(int beginIndex){ [
:(M<u`y>
this.beginIndex = beginIndex; F[giq1#
} D`@U[ `Sw
X{5 DPhB,
/** $GKm`I"
* @return e<wj5:M|
* Returns the currentPage. +s 0Bt '
*/ %l P
publicint getCurrentPage(){ @Sd:]h:f-
return currentPage; 4 sgwQ$m)
} `r bqYU0
6_
0w>
/** v-aq".XQ
* @param currentPage
2Ab#uPBn
* The currentPage to set. xa^HU~
*/ q`K-T_<
publicvoid setCurrentPage(int currentPage){ ?{Z0g+B1
this.currentPage = currentPage; I%WK*AORM
} 5"]2@@b4
+>%+r
/** )Ea_:C'
* @return Xr;noV-X
* Returns the everyPage. W3j|%
*/ l[0P*(I,
publicint getEveryPage(){ 6spk* 8e
return everyPage; 6M|%nBN$|
} c<x6_H6[8
HcUz2Rm5XP
/** K1WoIv<Ym
* @param everyPage uzA'D ~)P
* The everyPage to set. @z RB4d$
*/ 4}FfHgpQ
publicvoid setEveryPage(int everyPage){ 0PbIWy'
this.everyPage = everyPage; 0'}?3/u-
} E%:zE Q
p&M'DMj+
/** #a l^Uqd
* @return 6-YR'ikU
* Returns the hasNextPage. Vb#@o) z
*/ R?Q-@N>wE
publicboolean getHasNextPage(){ ?LFSR
return hasNextPage; G{Q'N04RA
} <LZvh8
mR@Xt#
/** o/
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* @param hasNextPage ZEJadR
* The hasNextPage to set. D/`E!6Fk=
*/ VMXXBa&
publicvoid setHasNextPage(boolean hasNextPage){ pa73`Ca]
this.hasNextPage = hasNextPage; 1uQf}
} H)+kN'J
m%\[1|N
/** JH;DVPX9z
* @return Q^Z}Y~.
* Returns the hasPrePage. [SvwJIJJ
*/ ]}l!L;
publicboolean getHasPrePage(){ .e+UgCwi
return hasPrePage; jU~%5R
} Oei2,3l,?
(%!R
/** m(P)oqwM
* @param hasPrePage c!T{|'?
* The hasPrePage to set. s~w+bwr
*/ L,/i%-J3c
publicvoid setHasPrePage(boolean hasPrePage){ #|i{#~gxM
this.hasPrePage = hasPrePage; #OTsD+2Za=
} o>tT!8rH
t1^96@m^
/** &Hxr3[+$
* @return Returns the totalPage. *p!dd?8
* m m`3-F|
*/ 0/]vmDr
publicint getTotalPage(){ [{*#cr f
return totalPage; QD~`UJe>
} YPEd
XU8}
U:e9Vq'N m
/** b2%[9)"I.
* @param totalPage h`j gF
* The totalPage to set. /XB1U[b
*/ 0^z$COCv
publicvoid setTotalPage(int totalPage){ uy{KV"%"^g
this.totalPage = totalPage; 1hG O*cq!
} BI]t}7
WG{/I/bJ_
} d`/{0 :F
9@B+$~:}7
2[hl^f^%,
OpE+e4~IF
T5;D0tM/
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 m`"s$\fah
KA#-X2U/
个PageUtil,负责对Page对象进行构造: Hkt'~L*
java代码: ]0le=Ee^%
+s}28U!
w%\;|y4+
/*Created on 2005-4-14*/ ZZ5yu* &
package org.flyware.util.page; 78-:hk
quYZD6IH
import org.apache.commons.logging.Log; tPHiz%
import org.apache.commons.logging.LogFactory; '*;rm*n
~s_$a8
/** ^B9wmxe
* @author Joa |93%,
* 'c D"ZVm1
*/ 8<xy*=%
publicclass PageUtil { ffVYlNQ7L
3R><AFMY?
privatestaticfinal Log logger = LogFactory.getLog (" %yV_R
~/%){t/uLY
(PageUtil.class); oH0\6:S
)%7A. UO)
/** enj2xye%Y
* Use the origin page to create a new page %9.KH
* @param page AF-.Nwp
* @param totalRecords RT>3\qhZ
* @return !@X#{
*/ o_n.,=/cZ
publicstatic Page createPage(Page page, int K3^2R-3:8
CmZ?uo+Y
totalRecords){ s>X;m.<
return createPage(page.getEveryPage(), 10&A3C(E
m.*+0NG
page.getCurrentPage(), totalRecords); Q~kwUZ
} u4'Lm+&O
uJ$,e5q
/** >Z%^|S9
* the basic page utils not including exception :xV&%Qa1
4
#N#[;M
handler /a_|oCeC}
* @param everyPage SccU@3.X~
* @param currentPage ?*;zS%93U9
* @param totalRecords 49m/UeNZ
* @return page GFidriC
*/ ov~m?Y]h
publicstatic Page createPage(int everyPage, int ~0NZx8qG
')+EW"
e
currentPage, int totalRecords){ #C`!yU6(
everyPage = getEveryPage(everyPage); n_<]9
currentPage = getCurrentPage(currentPage); ZU|nKt<GK
int beginIndex = getBeginIndex(everyPage, i=4bY[y
QQ9Q[c
currentPage); rSk $]E ]Z
int totalPage = getTotalPage(everyPage, JoYzC8/r
?cvv!2B]T
totalRecords); x1~`Z}LX0
boolean hasNextPage = hasNextPage(currentPage, b/EvcN8 }
)+G(4eIT
totalPage); Q7\Ax0
boolean hasPrePage = hasPrePage(currentPage); =bzTfki
\Mi< ROp5
returnnew Page(hasPrePage, hasNextPage, N?XN$hwdZ
everyPage, totalPage, ,]MX&]
currentPage, mR^D55k
bCF63(0
beginIndex); a
srkuAS
} 4$^=1ax
jc<3\ 7
privatestaticint getEveryPage(int everyPage){ weOMYJO;8
return everyPage == 0 ? 10 : everyPage; cg~FW2Q
} U
uysG\
?>_.~b~
privatestaticint getCurrentPage(int currentPage){ pV!(#45 ~W
return currentPage == 0 ? 1 : currentPage; '54@-}D
} f
{
ueI<
X%dOkHarB
privatestaticint getBeginIndex(int everyPage, int 4*3vZ6lhu
#/:[ho{JQ
currentPage){ wmIq{CXx,
return(currentPage - 1) * everyPage; + |,CIl+
} ,y.0Cb0
JnZxP> 2B
privatestaticint getTotalPage(int everyPage, int b6lL8KOu
sDiYm}W
totalRecords){ .UcS4JU
int totalPage = 0; y+PukHY
pd6d(
if(totalRecords % everyPage == 0) e:l 6;
totalPage = totalRecords / everyPage; R3~&|>7/T
else (F)zj<{f
totalPage = totalRecords / everyPage + 1 ; ivm.ng[
A9#2.5
return totalPage; t*x;{{jL#(
} [Y*UCFhI0
ubLLhf
privatestaticboolean hasPrePage(int currentPage){ .28*vkH%C=
return currentPage == 1 ? false : true; o8,K1ic5#
} k"Is.[I?^
0kkiS3T
privatestaticboolean hasNextPage(int currentPage, _D:/?=y;e
EW`3h9v~
int totalPage){ !|!V}O
return currentPage == totalPage || totalPage == $`
>C i=H(8vN
0 ? false : true; "$)2|
} 1a<,/N}}t
^2=zp.)
Gd"*mLd
} 4-m%[D
|W
3FdoADe{{
QZ6M,\
8_lD*bEt
^K"`k43{
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。 ]?r8^L yZ4
i8{jMe!Sa
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 5&>(|Y~I
82<L07fB
做法如下: ()?)Ybqss
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 pv T!6+
\|(;q+n?k
的信息,和一个结果集List: [bp"U*!9P
java代码: 1.!(#I3
k\lj<v<vD
\!PC:+uJ
/*Created on 2005-6-13*/ fZZ!kea[
package com.adt.bo; E'ZWSpP
~ce.&C7cR
import java.util.List; p|((r?{
LOA
90.D
import org.flyware.util.page.Page; gO5;hd[l
_:gV7>S?
/** J kA~Ol
* @author Joa +bSv-i -
*/ n33SWE(
publicclass Result { {ys_uS{c*
H)p{T@
private Page page; V>nY?
%~h'#S2X(
private List content; I;7{b\t
Q
Rpr#
,|
/** 'e&4#VLH^
* The default constructor FLWz7Rj
*/ :!/}*B
public Result(){ <Z&gAqj 2
super(); BoXCc"q[
} %*uqtw8
uJWX7UGuz
/** KDhHp^IXQ
* The constructor using fields =19]a
* "P|G^*"~2
* @param page 1#@'U90xf
* @param content }QI*Ns
*/ `A'*x]l
public Result(Page page, List content){ giTlXz3D9
this.page = page; ABSeX
this.content = content; A=])pYE1
} 8RK\B%UW
saZ;ixV
/** Y7p#K<y]9
* @return Returns the content. 0I
k@d'7
*/ s?2;u p*D
publicList getContent(){ VcP#/&B|
return content; 48DsRy
} k X-AC5]
k >MgrtJI
/** H!A^ MI
* @return Returns the page. jPd<h{js
*/ m/ukH{H1%
public Page getPage(){ \kRBJ1)|f
return page; ] *Hz'
} :Cuae?O,
t_N
`e(V
/** g(`6cY[}
* @param content i^>
RjR
* The content to set. *qqFIp^
*/ @s/ qOq?
public void setContent(List content){ h"'f~KM9a>
this.content = content; s.~SV"
} #4hP_Vhc
kju:/kY A
/** ,^[s4
=3X?
* @param page Qw^tzP8
* The page to set.
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*/ k.0C*3'
publicvoid setPage(Page page){ KIS.4nt#d"
this.page = page; ]uZH 0
} u-W=~EO5#
} $ D89|sy
eyM3W}[S$/
&>/nYvuq -
3S9~rLrn?
T;% SB&
2. 编写业务逻辑接口,并实现它(UserManager, "~
`-Jkm
fG{oi(T
UserManagerImpl) 07#!b~N
java代码: Hy6Np62
p[wjHfIq
3ty){#:
/*Created on 2005-7-15*/
y5#_@
package com.adt.service; w.3R1}R
\<8!b{F
import net.sf.hibernate.HibernateException; XC$~!
^T[#rNkeL
import org.flyware.util.page.Page; c1/x,1LnMf
uqn Z
import com.adt.bo.Result; 0eLK9u3<
^\I$tnY`
/** B^qB6:\t
* @author Joa M{H&5 9v
*/ -7`J(f.rYC
publicinterface UserManager { 4{R`
}lY-_y
public Result listUser(Page page)throws j Hzy1P{?
&qC>*X.
HibernateException; E%'DIs
yx-"YV}5
} ,>^~u
]]7T5'.
HfF$>Z'kM
|RmBa'.)z
cBA[D~s
java代码: Nt'5}
BO_^3Me*
rQqtejcfx
/*Created on 2005-7-15*/ 7[)(;-
package com.adt.service.impl; !9
F+uc5
9p.>L8
import java.util.List; f[RnL#*xJU
Xx^c?6YM
import net.sf.hibernate.HibernateException; S]N4o'K}q
AM[:Og S
import org.flyware.util.page.Page; Ef!F;D e)A
import org.flyware.util.page.PageUtil; ]'G7(Y\)f
d
!H)voX
import com.adt.bo.Result; }pA4#{)
import com.adt.dao.UserDAO; twn@~$
import com.adt.exception.ObjectNotFoundException; tFwlx3
import com.adt.service.UserManager; \
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ka*UyW}
/** yV. P.Q
* @author Joa . ~<+
*/ |?>h$'
publicclass UserManagerImpl implements UserManager { tu'M YY
l.BNe)1!22
private UserDAO userDAO; DH^^$)
8vo}
.JIl
/** erqB/ C
* @param userDAO The userDAO to set. UO wNcY
*/ |`nVr>QF&
publicvoid setUserDAO(UserDAO userDAO){ IFY!3^;zO
this.userDAO = userDAO; -&?-
} 4Q>F4v`
-%.V0=G(Z
/* (non-Javadoc) iH>djGhTh
* @see com.adt.service.UserManager#listUser U*@_T 3N
{ SfU!
(org.flyware.util.page.Page) `g=~u{0
*/ *pMA
V[^
public Result listUser(Page page)throws #5D+XB T
DkIFvsLK
HibernateException, ObjectNotFoundException { H[r0jREK
int totalRecords = userDAO.getUserCount(); lg1D>=(mY
if(totalRecords == 0) f"Iyo:Wt
throw new ObjectNotFoundException 2?j1~ ]DvZ
)B_h"5X4\y
("userNotExist"); zvD5i,I
page = PageUtil.createPage(page, totalRecords); f/yK|[g~
List users = userDAO.getUserByPage(page); >UMnItq(l
returnnew Result(page, users); )sHPIxHI
} %vXQ Sz
s,Swlo7D!
} c'2ra/?k
@jHio\/_
(R-Q9F+;
~'3% Qr
je-s%kNlJ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q1Ao65
l&B'.6XKs
询,接下来编写UserDAO的代码: U&R$(k0zS
3. UserDAO 和 UserDAOImpl: @XmkIm
java代码: 67x^{u7
jH1~Ve+q9
:X
f3wP=
/*Created on 2005-7-15*/ R.N*G]K5
package com.adt.dao; B}X#oA
e=jO_[
import java.util.List; 5MJ'/Fy(
"puz-W'n
import org.flyware.util.page.Page; R{_IrYk
mQd?Tyvn
import net.sf.hibernate.HibernateException; @ni~ij
_=5ZB_I
/** Kdm5O@tq
* @author Joa &u-Bu;G.e
*/ k 9rnT)YU
publicinterface UserDAO extends BaseDAO { $nn5;11@gY
G.8b\E~
publicList getUserByName(String name)throws qS
al~
)v~]lk,o
HibernateException; -e>)yM `i
Z"Oa5V6[A
publicint getUserCount()throws HibernateException; ?W_U{=anl
@g~sgE}#
publicList getUserByPage(Page page)throws aehMLl9cl
`'WLGQG
HibernateException; Kf#!IY][
s jm79/
} W+?[SnHL/
9DX3]Z\7X
G,*s9P]1
98^6{p
"'Uk0>d=_I
java代码: B:cOcd?p
Q%^bA,$&D
6l'y
/*Created on 2005-7-15*/ h>0<@UP
package com.adt.dao.impl; %<yM=1~>
M7,MxwZ0k
import java.util.List; u7WM6X
4sjr\9IDC
import org.flyware.util.page.Page;
+;;%Atgn
1o>R\g3
import net.sf.hibernate.HibernateException; 8[;oUVb5
import net.sf.hibernate.Query; (B<AK4G
KTt$Pt/.
import com.adt.dao.UserDAO; Xkom@F~]
:'~ gLW>j
/** "b4iOp&:=
* @author Joa (L%q/$
*/ yXg1N
N
public class UserDAOImpl extends BaseDAOHibernateImpl u^%')Ncp
/}_c7+//
implements UserDAO { :n9~H+!
7G/|e24
/* (non-Javadoc) Ws)X5C=A
* @see com.adt.dao.UserDAO#getUserByName tY'QQN||
pVS2dwBqE
(java.lang.String) }c ;um
*/ \/'n[3x
publicList getUserByName(String name)throws 5C1Rub)
K"j=_%{
HibernateException { 9dtGqXX
String querySentence = "FROM user in class :iB%JY Ad
@;D}=$x
com.adt.po.User WHERE user.name=:name"; :b*`hWnQ
Query query = getSession().createQuery Z[u,1l.T
K/v-P <g
(querySentence); Q0Qm0B5eY
query.setParameter("name", name); k<zGrq=8J
return query.list(); 2Q|*xd4B^
} UMQW#$~C{g
3}{5
X'
/* (non-Javadoc) 5'Jh2r
* @see com.adt.dao.UserDAO#getUserCount() N('DIi*or
*/ ,9wenr
publicint getUserCount()throws HibernateException { R(N(@KC
int count = 0; 7u5\#|yL
String querySentence = "SELECT count(*) FROM u%T$XG
%yM'
Z[-
user in class com.adt.po.User"; N 3p 7 0
Query query = getSession().createQuery ."Ix#\|x
g*?+~0"`Y
(querySentence); =GKYroNM
count = ((Integer)query.iterate().next GtJ*&=(
$1zeY6O
()).intValue(); 'O2#1SWe
return count; Q;ZHx.ye{
} \}QuNwc
0$Y 9>)O
/* (non-Javadoc) ([dL:Fb
* @see com.adt.dao.UserDAO#getUserByPage afiK!0col2
K6*UFO4}i
(org.flyware.util.page.Page) vq:OH
H
*/ i2a"J&,6O
publicList getUserByPage(Page page)throws 'ag6B(0Z
dIa(</ }
HibernateException { m4U+,|Fa
String querySentence = "FROM user in class WfT)CIKs
X#I`(iHY
com.adt.po.User"; m2q;^o:J
Query query = getSession().createQuery 'h6}cw+K
fMEv85@JL
(querySentence); :CST!+)o
query.setFirstResult(page.getBeginIndex()) C1B3VG
.setMaxResults(page.getEveryPage()); qvU$9cTY
return query.list();
G<-9U}~76
} >l< ~Z;
ElR&scXi__
} +<WRB\W
NU&^7[!yl
KR+BuL+L
4B8S e
Y:!/4GF
至此,一个完整的分页程序完成。前台的只需要调用 xCp+<|1
?~JxO/K
userManager.listUser(page)即可得到一个Page对象和结果集对象 MRg\FR2>1
T19rbL_
的综合体,而传入的参数page对象则可以由前台传入,如果用 u~- fK'/!|
QB3d7e)8>
webwork,甚至可以直接在配置文件中指定。 }d3N`TT
{_toh/8)r
下面给出一个webwork调用示例: eIUuq&(
java代码: i=X*
w^rb|mKo
a}qse5Fr
/*Created on 2005-6-17*/ M`+e'vdw
package com.adt.action.user; k CW!m
gUH'DS]{
import java.util.List; Hdbnb[e
UK~B[=b9
import org.apache.commons.logging.Log; 9p\Hx#^
import org.apache.commons.logging.LogFactory; .W@4vrp@
import org.flyware.util.page.Page; K[LVT]3 n
q"LJwV}W
import com.adt.bo.Result; y }&4HrT&
import com.adt.service.UserService; <% 7P
import com.opensymphony.xwork.Action; }y-;>i#m=g
|
2.e0Z]k
/** j`|^s}8t
* @author Joa Ld}(*-1i
*/ cbu nq"
publicclass ListUser implementsAction{ NM1cyZ
C*EhexK,}
privatestaticfinal Log logger = LogFactory.getLog 2 ]DCF
7Z`Mt9:Ht
(ListUser.class); N[bRp
%%+mWz a
private UserService userService; v(Bp1~PPZM
uH
ny ]
private Page page; !M]%8NTt2
:,%J6Zh?
privateList users; 3Zaq#uA
N0K>lL=
/* cbh#E)['
* (non-Javadoc) o,CA;_
* 6R-C0_'h
* @see com.opensymphony.xwork.Action#execute() uhTKCR~
*/ ~.W=
publicString execute()throwsException{ Wd^lt7(j
Result result = userService.listUser(page); OC?Zw@
page = result.getPage(); 18O@ 1M
users = result.getContent(); '"xL}8HX}
return SUCCESS; +24|_Lx0
} 3b|7[7}&
o%Uu.P
/** >
h,y\uV1
* @return Returns the page. )RA\kZ "
*/ 2Ft8dfdm`
public Page getPage(){ k(-Z@
return page; CQBT::
} $^vp'^uW>
`i t+D
/** 6^]`-4*W
* @return Returns the users. Mt[Bq6}ZD
*/ !cN?SGafZI
publicList getUsers(){ ;Na8_}
return users; nW$A^
} Z]x5!
:kME
/** Y)Znb;`?a
* @param page ){O1&|z-
* The page to set. HUU >hq9
*/ Kf05<J!
publicvoid setPage(Page page){ &*(n<5wt
this.page = page; 2I]]WBW#:
}
rV8(ia
#$rf-E5g-K
/** 00`bL
* @param users kZU"Xn
* The users to set. B^i mG
*/ r~Y>+ln.
publicvoid setUsers(List users){ *D=K{bUe'
this.users = users; U OR _M5
} !y>lOw})Q
yfSiByU
/** ,_.@l+BM.
* @param userService 6C:x6'5[
* The userService to set. kf+JM/
*/ JdaFY+f:
publicvoid setUserService(UserService userService){ ee&nU(pK
this.userService = userService; $xRo<,OV+
} zQL!(2
} F-$Z,Q]S
0M#N=%31
nmD1C_&
CDQJ bvx
X+`ddX
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, -@%t"8
U9<_6Bsd
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 _-@ZOhw&
n\Z^K
么只需要: ?)!Sm N/
java代码: F1 <489
I$aXnd6)
/J1S@-
<?xml version="1.0"?> 9M1a*frxZ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ((-aC`
-;+m%"k5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- H<V+d^qX\w
}x:\69$
1.0.dtd"> $!3gN%
/\TQc-k?2
<xwork> }7iUagN
4]"a;(
<package name="user" extends="webwork- ..??O^
#C"7
l6'a
interceptors"> fzLANya
,]f) ,;=
<!-- The default interceptor stack name ?@_v,,|
rumAo'T/%
--> >:.w7LQy/
<default-interceptor-ref rU;
g0'4e
*mf}bTiS
name="myDefaultWebStack"/> 5>'?:jY
hX0RET
<action name="listUser" G+ :bL S#:
2#'rk'X,K
class="com.adt.action.user.ListUser"> VKT@2HjNT`
<param V)2"l"Kt
@ L\-ZWq
name="page.everyPage">10</param> 5XzrS-I+X@
<result 'GrRuT<
?$<SCN=
name="success">/user/user_list.jsp</result> d-hbvLn
</action> XXXljh6
j'k8^*M6
</package> L5R `w&Up
;JAK[o8i
</xwork> i B%XBR
dj3|f{kg{
&K06}[J
kXigX-
b+W)2rFO
ah 4kA LO
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 W7%p^;ZQ$
zs4>/9O
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。 P`}$-#D F
Pg7>ce
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 e%pu.q\gK
{V.Wk
Z/xV\Ggx
MO[c0n%
/^d. &@*
我写的一个用于分页的类,用了泛型了,hoho y= 2=DU
5RW@_%C
java代码: s5Pq$<
b([:,T7
]F*|U`
package com.intokr.util; v,n);
S<V-ZV&_:U
import java.util.List; R_maNfS]Z
<[bQo&B2 E
/** JK[T]|G
* 用于分页的类<br> pV8[l) J
* 可以用于传递查询的结果也可以用于传送查询的参数<br> }(m1ql
* N"S3N)wgd
* @version 0.01 J(4g4?
* @author cheng t5%TS:u
*/ 9`&?hi49nK
public class Paginator<E> { Y^4q9?2G
privateint count = 0; // 总记录数 0%/,>IR>r
privateint p = 1; // 页编号 |4=ihB9+
privateint num = 20; // 每页的记录数 gRHtgR)T3
privateList<E> results = null; // 结果 n4Vwao/9x
64SW
/** H4W1\u
* 结果总数 Ih; aBS
*/ aUAcRW
publicint getCount(){ # ?_#!T|
return count; nQ|GqU\oA
} $Tfm/ =e
)W#T2Z>N1
publicvoid setCount(int count){ 18jJzYawh
this.count = count; S,XKW(5
} YDW|-HIF
jg?bf/$s
/**
%W(^6p!
* 本结果所在的页码,从1开始 nkTYWw
* (9E( Q*J5x
* @return Returns the pageNo. / HL_$g<
*/ nMkOUW:T!
publicint getP(){ {yTpRQN~
return p; ]{<saAmJC
} To pHE
^1R"7h
/** Vu=] O/ =P
* if(p<=0) p=1 aFyh,
* ,}KwP*:Z
* @param p |hc\jb
*/ l(#1mY5!q8
publicvoid setP(int p){ grc:Y
if(p <= 0) >}CEN
p = 1; M%3Wy"YQ,n
this.p = p; GKCM|Y
}
"3wv:BL
hzq5![/sV
/** ?HV }mS[t
* 每页记录数量 t-x[:i
*/ zOL;"/R
publicint getNum(){ ;uK";we
return num; *<7l!#
} s"q=2i
)J&|\m(e
/** a#$N% =j
* if(num<1) num=1 Yc|uD-y
*/ ]W;:|/,c
publicvoid setNum(int num){ zz&vfO31J
if(num < 1) UoHd -
num = 1; oXdel
Ju?
this.num = num; Zb"jB$58
} Xo\S9,s{
\X5 3|Y;=
/** ';Nu&D#Ph
* 获得总页数 _W}(!TKO
*/ ^zgacn
publicint getPageNum(){ ?,>5[Ha^?
return(count - 1) / num + 1; "T7>)fbu
} zSKKr?{
GB=bG%Tb
/** =HS4I.@c_5
* 获得本页的开始编号,为 (p-1)*num+1 [ZD[a6(94
*/ hXc}r6<B
publicint getStart(){ AX;c}0g
return(p - 1) * num + 1; e?P%wqB
} }3J=DCtS
eIJ[0c b}
/** eVx~n(m!}
* @return Returns the results. Y.NE^Vn0
*/ 6A?8tm/0
publicList<E> getResults(){ $it@>L8
return results; lov%V*tL
} x9&p!&*&IT
>azEed<B
public void setResults(List<E> results){ 6}#"qqnx
this.results = results; 8ljuc5,J
} l!:^6i
lm*g Gy1i
public String toString(){ 2T?TM! \Q
StringBuilder buff = new StringBuilder zqf[Z3
z&F5mp@
(); +?Ez}
BP
buff.append("{"); m8+:=0|$
buff.append("count:").append(count); 8SZK:VE@
buff.append(",p:").append(p); `;cz;"
buff.append(",nump:").append(num); :3O5ET'1
buff.append(",results:").append KUFz:&wK
G|*G9nQ
(results); n]iyFZ`9
buff.append("}"); bcn7,ht
return buff.toString(); ot }6D
} #q;z8 @
|z*>ixK
} 3ev -Iqz
+`Pmq}ey
#kci=2q_