Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 s}X2*o`,
zGA1
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Np+<)q2
,n^{!^JW
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
mM!Gomp
=5',obYN>c
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 :[,-wZiT~6
tVFl`Xr
。 lfK sqe"
3hGYNlQ^
分页支持类: <U$x')W
<Y9e n!3\
java代码: GK~uoz:^O
t#=W'HyW8
|!,;IoZ
package com.javaeye.common.util; 1F{c5
X8"4)IZ3
import java.util.List; Z`T]jm-3
=YOq0
publicclass PaginationSupport { ^e1@o\]
/&_$+Iun
publicfinalstaticint PAGESIZE = 30; MA6(VII
VMXccT9i!
privateint pageSize = PAGESIZE; b<n*wH
jH({Qc,97
privateList items; fX2sjfk
X0.k Q
privateint totalCount; F}wy7s2i
Kejp7okb
privateint[] indexes = newint[0]; wQEsq<
d)1 d0ES
privateint startIndex = 0; SFv'qDA
g1Ed:V]_
public PaginationSupport(List items, int -U.>K,M
9sJ=Nldq
totalCount){ TkBHlTa"=
setPageSize(PAGESIZE); gNUYHNzDM(
setTotalCount(totalCount); u%!/-&?wF
setItems(items); GRM6H|.
setStartIndex(0); nm Y_ )s
} nl5A{ s
#oW"3L{,
public PaginationSupport(List items, int 0Ta&o-e
E2K{9@i
totalCount, int startIndex){ X|y(B%:
setPageSize(PAGESIZE); vJ9I z
setTotalCount(totalCount); /W9(}Id6
setItems(items); \2)D
setStartIndex(startIndex); ;x%"o[[>
} <-;/,uu
,cE yV74
public PaginationSupport(List items, int `,QcOkvbC
VK286[[fv
totalCount, int pageSize, int startIndex){ @QteC@k
setPageSize(pageSize); 0v+-yEkw
setTotalCount(totalCount); 2,aH1Xbex
setItems(items); /s*.:cdH
setStartIndex(startIndex); e`n+U-)z
} _Z7`tUS-j
txE=AOY5
publicList getItems(){ t.y-b`v
return items; :^7>kJ5?
} z_93j3#
O,6Wdw3+-3
publicvoid setItems(List items){ MH=7(15R
this.items = items; ;NU-\<Q{
} `6$|d,m5
)Zf1%h~0r
publicint getPageSize(){ 5EU~T.4C<
return pageSize; 7UIf
} {Y-~7@
0FSN IPx
publicvoid setPageSize(int pageSize){ A]Bf&+V
this.pageSize = pageSize; Jvc:)I1NE7
} bTU[E
vAp<Muj(a
publicint getTotalCount(){ <qg4Rz\c]
return totalCount; J2<kOXXJ9
} ijsoY\V50
IjGPiC
publicvoid setTotalCount(int totalCount){ pHT]2e#
if(totalCount > 0){ H-vHcqFx3
this.totalCount = totalCount; 3xT9/8*
int count = totalCount / .G.WPVE
'2GnA ws^
pageSize; ^/_Yk.w
if(totalCount % pageSize > 0) /~MH]Gh
count++; o^XDG^35`
indexes = newint[count]; SQ_Je+X
for(int i = 0; i < count; i++){ KL9k9|!p
indexes = pageSize * fIl;qGz85
WQ{[q" O
i; wA\5-C7j
} v3#,Z!
}else{ W1 k]P.
this.totalCount = 0; )adV`V%=>
} `^52IkM)
} [Ur\^wS
Y{D%v
publicint[] getIndexes(){ g5
T
return indexes; 0z'GN#mT5
} S=(<m%f
ia7<AwV
publicvoid setIndexes(int[] indexes){ m8ts!6C
this.indexes = indexes; DmpT<SI+!
} s3HVX'
-8xf}v~u
publicint getStartIndex(){ |GtvgvO,
return startIndex; y{S8?$dU$:
} d2V X\
y(o)}m*0
publicvoid setStartIndex(int startIndex){ p}^5ru
if(totalCount <= 0) RFMPh<Ac
this.startIndex = 0; 3V<@Vkf5
elseif(startIndex >= totalCount) .4p3~r?=S
this.startIndex = indexes AH|gI2
s'h;a5Q1'Q
[indexes.length - 1]; =hkYQq`Q
elseif(startIndex < 0) '`3#FCg
this.startIndex = 0; |RFBhB/u
else{ odCt6Du
this.startIndex = indexes &W,jR|B
yEq7ueJ'
[startIndex / pageSize]; K#YQB3rX
} .^?zdW
} $P=C7;
R|C2O[r}
publicint getNextIndex(){ U}LW8886
int nextIndex = getStartIndex() + MF8-q'upyT
=j62tDS
pageSize; _p^"l2%D/
if(nextIndex >= totalCount) d=/0A\O
return getStartIndex(); J0?kEr
else |M7cB$y
return nextIndex; P(hGkY=(
} xSm;~')g
&3BoK/y3
publicint getPreviousIndex(){ Ttt'X<9
int previousIndex = getStartIndex() - uMJ\
/]_ t->
pageSize; q.c)>=!.
if(previousIndex < 0) Y !?'[t
return0; W6&vyOc
else _!nsEG
VV
return previousIndex; [ QiG0D_'=
} H"#ITL
yO q@w!xz
} wT4@X[5$
E5w;75,
9af.t
{'5"i?>s0>
抽象业务类 O`B,mgT(
java代码: <h/%jM>9/
`ePC$Ovn
0f^{Rp6
/** -QrC>3xZR
* Created on 2005-7-12 V)j[`,M:
*/ -L1785pB85
package com.javaeye.common.business; A*EOn1hN
Rff F:,b
import java.io.Serializable; wDJ`#"5p{
import java.util.List; v $Iw?y
''y.4dvX
import org.hibernate.Criteria; s/E|Z1pg3
import org.hibernate.HibernateException; Xw-[Sf]p
import org.hibernate.Session; Y{p$%
import org.hibernate.criterion.DetachedCriteria; q,vWu(.
import org.hibernate.criterion.Projections; uM-,}7f7
import or/gx 3
zx3gz7>k;
org.springframework.orm.hibernate3.HibernateCallback; qN $t_
import 0cd_l
2f#g
S6TNu+2w4
org.springframework.orm.hibernate3.support.HibernateDaoS x HRSzYn$
bGPE0}b
upport; l/&.H F
5*AXL.2ih
import com.javaeye.common.util.PaginationSupport; Zt `Tg7m
4:`D3
public abstract class AbstractManager extends hF%M!otcJ-
qt@L&v}~j
HibernateDaoSupport { JvpGxj
]~({;;3o-
privateboolean cacheQueries = false; O>~,RI!
<+`%=r)4
privateString queryCacheRegion; WsI`!ez;D
!@xO]Jwv
publicvoid setCacheQueries(boolean
Vy\Vpp
> |$]=e,Z
cacheQueries){ l<6u@,%s
this.cacheQueries = cacheQueries; @(3F4Z.i%.
} mdj%zJ8/
`o[l%I\Q
publicvoid setQueryCacheRegion(String Dac)`/
{.p.?
queryCacheRegion){ /jY
u-H+C
this.queryCacheRegion = Yj%]|E-
jD:
N)((
queryCacheRegion; %;PpwI
} Q7BbST+
{& o^p!
publicvoid save(finalObject entity){ t" .Ytz>
getHibernateTemplate().save(entity); BVQy@:K/
} X8nos
o
NtFYY
publicvoid persist(finalObject entity){ eqbN_$>
getHibernateTemplate().save(entity); #9vC]Gm
} Shm> r@C?
EBj^4=b[
publicvoid update(finalObject entity){ (WM3(US|
getHibernateTemplate().update(entity);
Dw-d`8*
} vgz`+Zj*S
!wAT`0<94F
publicvoid delete(finalObject entity){ |=?#Xbxz
getHibernateTemplate().delete(entity); NAbVH{*\U
} asT-=p_ 0.
oQ!M+sRmF
publicObject load(finalClass entity, :E:e ^$p
T$4{fhV
\
finalSerializable id){ zWHq4@K
return getHibernateTemplate().load (]|h6aI'}
JJ?{V:
(entity, id);
Ei;tfB
} Z_d"<k}I
Vwkvu&4
publicObject get(finalClass entity, /:{%X(8
J2UQq 7-y
finalSerializable id){ q7R]!zk
return getHibernateTemplate().get +$2{u_m,
S;|:ci<[=
(entity, id); /jbAf ]"F;
} \br!77
Ey6R/M)?:y
publicList findAll(finalClass entity){ p>6`jr
return getHibernateTemplate().find("from bO '\QtW9
V%Uj\cv
" + entity.getName()); ,_[x|8m
} l$42MRi/
"M I';6
publicList findByNamedQuery(finalString A1WUK=P
|V9[aa*c
namedQuery){ d*(aue=
return getHibernateTemplate $TQhr#C]
&!!*xv-z
().findByNamedQuery(namedQuery); LQ+/|_(.
} ?jx]%n fV
-YRIe<}E -
publicList findByNamedQuery(finalString query, F:{*4b
Up9{aX
finalObject parameter){ s#2t\}/
return getHibernateTemplate %fS9F^AK
7)66e
().findByNamedQuery(query, parameter); 0-2|(9
Kc
} ,:_c-d#
h$cm:uks
publicList findByNamedQuery(finalString query, R4?>C-;
7|rH9Bc{U
finalObject[] parameters){ tne_]+
return getHibernateTemplate sZ;|NAx)
h
><Sp*z_V
().findByNamedQuery(query, parameters); E$8JrL
} mxc)Wm<4
Q7%4 `_$!
publicList find(finalString query){ kfy!T rf
return getHibernateTemplate().find 6Q.S
~9X^3.nI
(query); @AyteHK
} \Mf>X\}
PEMkx"h +
publicList find(finalString query, finalObject 9 {4yC9Oz>
\kADh?phV
parameter){ sNf& "C!;
return getHibernateTemplate().find fXD+
KA3U W
(query, parameter); d}
>Po%r:
} bIQ,=EA1
x4_IUIgh
public PaginationSupport findPageByCriteria .)Tj}Im2p
q"2QNF'
(final DetachedCriteria detachedCriteria){ v.0qE}'
|
return findPageByCriteria MKK ^-T
g \mE
(detachedCriteria, PaginationSupport.PAGESIZE, 0); N0`9/lr|
} [Nyt0l "z
$d?+\r:I{,
public PaginationSupport findPageByCriteria 6].[z+
MP]<m7669*
(final DetachedCriteria detachedCriteria, finalint =BJLj0=N
%sa?/pjK
startIndex){ `Sod]bO
+U
return findPageByCriteria 4u{S?Ryy
Y&|Z*s+
+}
(detachedCriteria, PaginationSupport.PAGESIZE, 6FS%9.Ws
kY0HP a
startIndex); $|4@Zx4vf
} [W[{
4 Xu
bS_#3T
public PaginationSupport findPageByCriteria #3uv^m LGa
(vXr2Z<l
(final DetachedCriteria detachedCriteria, finalint Sp`l>BL
FO{=^I5YA
pageSize, 1 ZdB6U0
finalint startIndex){ %6K7uvTq
return(PaginationSupport) t)SZ2G1r
|IxHtg3>6{
getHibernateTemplate().execute(new HibernateCallback(){ OL'Ito
publicObject doInHibernate P.~UUS
| dQ>)_
(Session session)throws HibernateException { W4$o\yA]
Criteria criteria = (d9~z
'
jciX]g
detachedCriteria.getExecutableCriteria(session); MK<
y$B{}
int totalCount = ('J/Ww<
''17(%
((Integer) criteria.setProjection(Projections.rowCount 4pmeu:26
I&PJ[U#~a
()).uniqueResult()).intValue(); zzmC[,u}
criteria.setProjection c:Ua\$)u3,
"be\%W+<
(null);
"Ih3
List items = ':4cQ4Z
Y,]Lk<Hm3
criteria.setFirstResult(startIndex).setMaxResults CEfqFn3^
aq,1'~8XR
(pageSize).list(); r&=ulg
PaginationSupport ps = g)Z8WH$;H3
R'c*CLaiE
new PaginationSupport(items, totalCount, pageSize, j
cd<'\;
<,vIN,Kl8/
startIndex); G':3U
return ps; X'A`"}=_
} /<[0o]
}, true); v>X!/if<y
} 2mY!gVi
V 6}5^W
public List findAllByCriteria(final 6@]o,O
$q!A1Fgk0
DetachedCriteria detachedCriteria){ (Tx_`rO4VY
return(List) getHibernateTemplate 0aT:Gy;
q ` S
~w
().execute(new HibernateCallback(){ Y:*% [\R
publicObject doInHibernate ~ !uX"F8Xl
z']6C9m}
(Session session)throws HibernateException { aZZ0eH
Criteria criteria = ^sv|m"
&X4anH>O
detachedCriteria.getExecutableCriteria(session); b42%^E
return criteria.list(); ;@+|]I
} FgdnX2s J
}, true); ^}
{r@F
} *F$@!ByV
)x-b+SC
public int getCountByCriteria(final s,R:D).
T CT8OU|
DetachedCriteria detachedCriteria){ \((MoQ9Qk
Integer count = (Integer) =By@%ioIGG
n"iS[uj,
getHibernateTemplate().execute(new HibernateCallback(){ *%uz LW0
publicObject doInHibernate U~
X
E}wT5t;u
(Session session)throws HibernateException { a\sK{`|X*
Criteria criteria = DJGafX^
*QK)
1Y1W
detachedCriteria.getExecutableCriteria(session); r3V1l8MV
return 5(~Lr3v0
!~
o%KQt
criteria.setProjection(Projections.rowCount [$3+5K#
z|s(D<*w
()).uniqueResult(); @$slGY
} /gAT@Vx
}, true); ^f[6NYS?
return count.intValue(); 0E\#!L
} 7_~sa{1R.
} D:`Q\za
V
x#M!os0
(KI9j7
K6{wM
#1dVp!?3T
bvD}N<>3N
用户在web层构造查询条件detachedCriteria,和可选的 |JkfAnrN$I
%9YY \a {
startIndex,调用业务bean的相应findByCriteria方法,返回一个 "#)|WVa=BM
/xX7:U b
PaginationSupport的实例ps。 nbxY'`8F
81nD:]7
ps.getItems()得到已分页好的结果集 )\])?q61
ps.getIndexes()得到分页索引的数组 j_C"O,WS
ps.getTotalCount()得到总结果数 Nu qmp7C
ps.getStartIndex()当前分页索引 ?}`-?JB1
ps.getNextIndex()下一页索引 y\v#qFVOZ
ps.getPreviousIndex()上一页索引 ~\=D@G,9
NV5qF/<M
?j&hG|W9<z
<zCWLj3
6B]=\H
~d7t\S
2l?^\9&
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 iM!Ya!
b}TvQ+W]2
,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 h6k" D4o\
-1Tr!I:1
一下代码重构了。 -k + jMH
;gBR~W
我把原本我的做法也提供出来供大家讨论吧: &G2&OFAr]q
)>2L(~W
首先,为了实现分页查询,我封装了一个Page类: n1%2sV)>
java代码: /<_!Gz.@uG
WIU]>_$.
BP..p ^EPN
/*Created on 2005-4-14*/ zgY VB}
package org.flyware.util.page; x[mz`0
xVB
rwkk(
/** "U^m~N9k{
* @author Joa #E+ybwA
* \MEBQ
*/ et5lfj
publicclass Page { .I_atv
bci]"uzB
/** imply if the page has previous page */ <M\&zHv
privateboolean hasPrePage; he(K
UIDeMz
/** imply if the page has next page */ yH('Vl
privateboolean hasNextPage;
Gd A!8
WVD48}HF-
/** the number of every page */ yKhI&
privateint everyPage; U4*u|A
YE@yts
/** the total page number */ e-*@R#x8+
privateint totalPage; r 10VFaly
5Pf=Uj6D
/** the number of current page */ o2dO\$'
privateint currentPage; 7;+G)44
Hc\C0V<
/** the begin index of the records by the current R?u(aY)P
a/uo)']B
query */ %Bw:6Y4LZ
privateint beginIndex; xc*a(v0
q\@_L.tc[
=4` wYh
/** The default constructor */ umns*U%T;
public Page(){ `U|7sLR
zG$5g^J
} D\G.p |9=
/a*){JQ5j
/** construct the page by everyPage F. U@8lr
* @param everyPage $B8Vg `+
* */ !Ew
ff|v"
public Page(int everyPage){ p-IJ':W
this.everyPage = everyPage; XB7*S*"!
} 46]BRL2 G
Iuz_u2"C
/** The whole constructor */ ~*bfS}F8I
public Page(boolean hasPrePage, boolean hasNextPage, /[dMw
*SRz
p _[,P7
7tWC<#
int everyPage, int totalPage, W8 Ssv
int currentPage, int beginIndex){ ^vMlRt;
this.hasPrePage = hasPrePage; M6&=-
this.hasNextPage = hasNextPage; 0U~$u
this.everyPage = everyPage; +YZo-tE
this.totalPage = totalPage; sJKr%2nVV
this.currentPage = currentPage; V?dwTc
this.beginIndex = beginIndex; M~\dvJ$cH
} XA<h,ONE?
oi|N8a2R
/** y5F+~z}{
* @return KANR=G
* Returns the beginIndex. hlL$3.]
*/ FkrXM!mJ
publicint getBeginIndex(){ |l8=z*v<