Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 yn20*ix{
jLY$P<u?%P
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f)V6VNW.3
)T&r770
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 $" =3e]<
ka{!' ^
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Mhb~wDQl
k9NHdi7&2
。 <xrya_R?
s;[=B
分页支持类: X`-o0HG
L)S
V?FBx
java代码: f]C^{Uk#
- (q7"h
et(AO)uv6
package com.javaeye.common.util; OB^j
b8
MUCes3YJH
import java.util.List; L$"pk{'
a]6dhQ`
publicclass PaginationSupport { e?
|4O<@
!CY*SGO
publicfinalstaticint PAGESIZE = 30; W'Y(@
~zvZK]JoX
privateint pageSize = PAGESIZE; "5Z5x%3I
vIZFI
privateList items; W@%g_V}C*
o3NB3@uj<
privateint totalCount; `=Bv+
mtw{7E
privateint[] indexes = newint[0]; IJ:JH=8
EN,}[^Z
privateint startIndex = 0; -zzT:C
6(Ntt
public PaginationSupport(List items, int (.wR!l#!
\NKw,`/
totalCount){ =.):tGDp
setPageSize(PAGESIZE); }^b
setTotalCount(totalCount); RXu`DWN
setItems(items); Zw<<p|{)<
setStartIndex(0); ?+%bEZ`
} N|
P?!G-=
FF|M7/[~
public PaginationSupport(List items, int [o7Qr?RN
axK/YE7t
totalCount, int startIndex){ [9F
setPageSize(PAGESIZE); 6JRFYgI
setTotalCount(totalCount); ivt ~S
setItems(items); v_pFI8Cz)
setStartIndex(startIndex); ",Fvv
} Sogt?]HB$
vTWm_ed+^
public PaginationSupport(List items, int 8.7lc2aX
5aXE^.`
totalCount, int pageSize, int startIndex){ ~\<L74BB
setPageSize(pageSize); 6['o^>\}f
setTotalCount(totalCount); &]A0=h2{P*
setItems(items); MlW*Tugg
setStartIndex(startIndex); ]mC5Z6,1s
} >McEuoZx9
KYl!Iw67d
publicList getItems(){ [8Z
!dj
return items; Ht]O:io`
} 5v=e(Ph+
@Q&k6.{4Z
publicvoid setItems(List items){ !HP=Rgh
this.items = items; dVn_+1\L
} Q]$pg 5O
&;<'AF
publicint getPageSize(){ QHnC(b
return pageSize; j6L (U~%
} O.8k [Ht
1?Tj
publicvoid setPageSize(int pageSize){ 8]bLp
this.pageSize = pageSize; h2i1w^f
} #)iPvV'
{.e^1qE
publicint getTotalCount(){ XPnHi@x
return totalCount; 0JqvV
} ,"YTG*ky
JBLh4c3
publicvoid setTotalCount(int totalCount){ C5e;U
if(totalCount > 0){ 7*He 8G[W
this.totalCount = totalCount; =j{Kxnv
int count = totalCount / 3~Ap1_9
["<'fq;PJ
pageSize; #%V+- b(
if(totalCount % pageSize > 0) )HX(-"c
count++; Y.#fpG'
indexes = newint[count]; 10bv%ZX7
for(int i = 0; i < count; i++){ _c}# f\ +_
indexes = pageSize * E@AV?@<sc
J=HN~B1
i; 0F
2p4!@W
} >&^jKfY
}else{ @3S:W2k
this.totalCount = 0; SzfMQ@~
} p\.IP2+c
} QFgKEUNgl
1y,/|Y
publicint[] getIndexes(){ 3UUN@Tx
return indexes; >gz8,&
} [X>f;;h
POX{;[SV
publicvoid setIndexes(int[] indexes){ 4Tb"+Y}
this.indexes = indexes; wti
} >5D;uTy
u
ViG>gMG v
publicint getStartIndex(){ \p]B8hLW
return startIndex; #wZH.i#
} n9R0f9:*
8xkLfN|N=
publicvoid setStartIndex(int startIndex){ U*go}dt"5
if(totalCount <= 0) I~;H'7|e
this.startIndex = 0; -zI9E!24
elseif(startIndex >= totalCount) Ka<J*
k3
this.startIndex = indexes <Pi#-r.,
.1_kRy2*.
[indexes.length - 1]; \^jRMIM==
elseif(startIndex < 0) wyXQP+9G
this.startIndex = 0; @rF|WT
else{ :H+8E5
this.startIndex = indexes MIh\z7gW
z<.?8bd
[startIndex / pageSize]; )lq+Gv[%F
} q1m{G1W
n
} ^`Hb7A(
aK
3'u
publicint getNextIndex(){ #7/39zTK
int nextIndex = getStartIndex() + cH+ ~|3
hML-zZ
pageSize; q>5j (,6F
if(nextIndex >= totalCount) cS
Qb3}a\
return getStartIndex(); Fh|{ib
else yhs:.h
return nextIndex; OB*V4Yv
} {<?8Y
.N`*jT
publicint getPreviousIndex(){ T)',}=
int previousIndex = getStartIndex() - Ba**S8{/`
:\y' ?d- Q
pageSize; IIAmx[ b
if(previousIndex < 0) L|6I
return0;
T;V!>W37
else DgY
!)cS
return previousIndex; |"+Ufw^
} `3@?)xa
l,zhBnD
} h[Uo6`
<1
;pyw
y
*N"CV={No
n=|% H'U
抽象业务类 C7DwA/$D
java代码: <XN=v!2;
NCl@C$W9q
d`~~Ww1
/** S5d
* Created on 2005-7-12 UM<s#t`\3
*/ W+$G{XSr5C
package com.javaeye.common.business; ? Dn}
l@ (:Q!Sk
import java.io.Serializable; \-f/\P/ w
import java.util.List;
qI${7
JYv<QsD
import org.hibernate.Criteria; =itQ@``r
import org.hibernate.HibernateException; / :6|)AW.{
import org.hibernate.Session; ]hoq!:>M1
import org.hibernate.criterion.DetachedCriteria; e[0"x.gu
import org.hibernate.criterion.Projections; `csZ*$7
import ga(k2Q;y
<fV][W
org.springframework.orm.hibernate3.HibernateCallback; yc`*zLWh
import q6<P\CSHy<
+-,iC6kK
org.springframework.orm.hibernate3.support.HibernateDaoS Vjw u:M
euVj,m
upport; -3guuT3x\
iq[IZdza
import com.javaeye.common.util.PaginationSupport; xc\zRsY`
d325Cw?
public abstract class AbstractManager extends F\L!.B
D/GE-lq
HibernateDaoSupport { "Mhn?PTq
Z!7xRy
privateboolean cacheQueries = false; y%spI/(
L"n)fe$
privateString queryCacheRegion; 6U.|0mG[
v+8Ybq
publicvoid setCacheQueries(boolean K1Uq`T J
fc9@l a
cacheQueries){ P.QF9%
this.cacheQueries = cacheQueries; -V;BkE76
} Ak8Y?#"wz
\4^rb?B
publicvoid setQueryCacheRegion(String (<8}un
D W^Zuu/)
queryCacheRegion){ ,wXmJ)/WZ
this.queryCacheRegion = )*S:C
14jN0\
queryCacheRegion; G$%F`R[
} w6WPfy(/2
)%3T1
D/
publicvoid save(finalObject entity){ Pg{1' -
getHibernateTemplate().save(entity); .T3 m%n
} T ~(Sc'8
m}\QGtJ6
publicvoid persist(finalObject entity){ >#k-
~|w
getHibernateTemplate().save(entity); ^_<|~
} 4+s6cQ]S`
RAP-vVh/C
publicvoid update(finalObject entity){ CxZh^V8LP
getHibernateTemplate().update(entity); nosD1sS.K8
} B4wRwrVI>
[~ 2imS
publicvoid delete(finalObject entity){ nw0#gDI|
getHibernateTemplate().delete(entity); / of K7/
} 2J8:_Ql3I
: -d_
publicObject load(finalClass entity, :dAd5v2f
q!?*M?Oz
finalSerializable id){ W)/^*,
Q7
return getHibernateTemplate().load "Y=`w,~~
T'@+MA) ~
(entity, id); \7"|'fz
} qc5[e
lg~7[=%k#
publicObject get(finalClass entity, $|.8@
nj
^B%=P
finalSerializable id){ l-l7jq]R
return getHibernateTemplate().get X<P
<-e9
x|(pmqIH+
(entity, id); #mA(x@:*
} Jk6}hUH,
\m
GY'0
publicList findAll(finalClass entity){ $2L6:&.P,
return getHibernateTemplate().find("from 6CIzT.
});Rjg
" + entity.getName()); 7-!n-
} Np/\}J&IF
Zo yO[#
publicList findByNamedQuery(finalString -4&
i t:
NX.xEW@
namedQuery){ %&|
uT
return getHibernateTemplate X3X_=qzc
`+"(GaZ
().findByNamedQuery(namedQuery); \/o$io,kV
} $t(v `,
4]ni-u0*
publicList findByNamedQuery(finalString query, E<[
s+iX
a[(OeVQ5
finalObject parameter){ G~YZ(+V%~
return getHibernateTemplate dkZe.pv$j
>m,hna]RZ
().findByNamedQuery(query, parameter); e12QYoh
} ,_I
rE
I/MY4?(T
publicList findByNamedQuery(finalString query, IrqM_OjC
(^m]
7l
finalObject[] parameters){ 0f.jW O
return getHibernateTemplate #e|o"R;/`
2 HEU
().findByNamedQuery(query, parameters); "J 1A9|
} ?<TJ}("/
49$<:{ ~
publicList find(finalString query){ Y(.e e%;,
return getHibernateTemplate().find h@!p:]
N8{jvat
(query); 7GYf#} N
} cR/Nl pX
jTvcKm|q
publicList find(finalString query, finalObject Gl1XRNyC
*;Mi/^pzK
parameter){ o8 JOpD
return getHibernateTemplate().find <$0is:]
4a+gM._+O
(query, parameter); b-sN#'TDg
} dm4Q'u
` 3qf}=Z`
public PaginationSupport findPageByCriteria 2@<_,'
49~d6fH
(final DetachedCriteria detachedCriteria){ ~v.mbh
return findPageByCriteria G`Nw]_
Z_
"w'pIUQ3,
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,PTM'O@aU#
} *9^8NY]
ew~Z/ A
public PaginationSupport findPageByCriteria >v.fH6P,}
P1Hab2%+
(final DetachedCriteria detachedCriteria, finalint &v{#yzM
#1DEZ4]jjY
startIndex){ e0zP LU}
return findPageByCriteria Z8#nu
u
]e-IYH
(detachedCriteria, PaginationSupport.PAGESIZE, &Q883A
J
i/x |c!E
startIndex); )4L2&e`k)(
} ^ `y7JXI:
nF <K84
public PaginationSupport findPageByCriteria uL`#@nI
!C#oZU]P
(final DetachedCriteria detachedCriteria, finalint f+cb83}n]
]#)(D-i
pageSize, |Vx[
finalint startIndex){ +'<PW+U$
return(PaginationSupport) g"m'
C6;
Zv;nY7B
getHibernateTemplate().execute(new HibernateCallback(){ fp' '+R[
publicObject doInHibernate hCcI]#S&
/iU<\+ H
(Session session)throws HibernateException { TTz=*t+D
Criteria criteria = ]y_:+SHc
@7twe;07r
detachedCriteria.getExecutableCriteria(session); -tj#BEC[H(
int totalCount = `Nx@MPo
Z7a@$n3h
((Integer) criteria.setProjection(Projections.rowCount WNGX`V,d
WHdM P
()).uniqueResult()).intValue(); !9;m~T7.
criteria.setProjection ~)U50.CH
&Hb%Q! ^Kb
(null); "lh4Vg\7n
List items = lYG`)#T
NN*L3yx
criteria.setFirstResult(startIndex).setMaxResults o$*(N
<fvu)
f
(pageSize).list(); Nw*<e ]uD
PaginationSupport ps = W"c\/]aD
JbPkC*.
new PaginationSupport(items, totalCount, pageSize, dy&G~F28
,hn#DJ)
startIndex);
XIInI
return ps; 7;EDU
} qUJ"* )S
}, true); {rc3`<%
} Lh[0B.g<
.-Lrrk)R+
public List findAllByCriteria(final >v+1v
a
!VWWUTm?
DetachedCriteria detachedCriteria){ ip-X r|Bq
return(List) getHibernateTemplate |a{;<a
COh#/-`\1
().execute(new HibernateCallback(){ q\EYsN</;
publicObject doInHibernate 8^UF0>`'
jY=y<R_oK
(Session session)throws HibernateException { 9O;Sn +
Criteria criteria = L7rgkxI7k*
/wJ#-DZ
detachedCriteria.getExecutableCriteria(session); &=[!L0{
return criteria.list(); MQoA\
} duG!QS:
}, true); <P h50s4
} &-=~8
jIs>>
public int getCountByCriteria(final hxoajexU
pP| @Z{7d`
DetachedCriteria detachedCriteria){ oco,sxT
Integer count = (Integer) z!g$#hmL>
\s)MNs
getHibernateTemplate().execute(new HibernateCallback(){ pJHdY)Cz
publicObject doInHibernate 9JA@m
w"'
Pn`T
(Session session)throws HibernateException { 6>]_H(z7
Criteria criteria = V4,Gt]4
rfwJLl/
detachedCriteria.getExecutableCriteria(session); a|t~&\@
return
/a1uG]Mt
h#YO;m2wd
criteria.setProjection(Projections.rowCount RTmp$lV
!n-Sh<8
()).uniqueResult(); Q!l(2nva
} Y$JVxly
}, true); 8_%GH}{
return count.intValue(); +=($mcw#[
} "'v+*H 3
} s<YN*~
Lf9hOMHx
Ey=2zo^F
_&-d0'+
#}^waYAk)
:
@|Rj_S;
用户在web层构造查询条件detachedCriteria,和可选的 z*},N$2=
fpf]qQ
W~7
startIndex,调用业务bean的相应findByCriteria方法,返回一个 YiZk|K_
m9[ 7"I
PaginationSupport的实例ps。 nah?V"
?Y
,WyEwc]
ps.getItems()得到已分页好的结果集 p/Ul[7A4e
ps.getIndexes()得到分页索引的数组 _[6sr7H!
ps.getTotalCount()得到总结果数 3 yx[*'e$
ps.getStartIndex()当前分页索引 ljbAfd
ps.getNextIndex()下一页索引 1V2]@VQF
ps.getPreviousIndex()上一页索引 +R*DE5dz
dj0%?g>
%+'Ex]B
9nAP%MA`
NJBSVCb
irlFB#..
n-9xfn0U~#
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XM\\Imw
>w.;A%|N
,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|!{
}TTghE!
一下代码重构了。 <+*0{8?0
y(|#!m?@
我把原本我的做法也提供出来供大家讨论吧: 3q%z
zmhc\M?z
首先,为了实现分页查询,我封装了一个Page类: &{j!!LL
java代码: ?M:>2wl
eA&