Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4BYE1fUzd
Am0{8
'
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
'7Nr8D4L
Cb t{H}I3
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 ]M>9ULQ
N]EcEM #
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 d6{Gt"
f*{
YFg?*&
。 sxKf&p;
:AdDLpk3j
分页支持类: -~[9U,
/^{BUo
java代码: 7\zZpPDV
JCcZuwu[
9fnA
package com.javaeye.common.util; #o/H~Iv
5Z/GK2[HL
import java.util.List; hRI"y":zD
cq&*.
publicclass PaginationSupport { GDhE[of
anw}w!@U
publicfinalstaticint PAGESIZE = 30; #PDf,^
SKuIF*"!S
privateint pageSize = PAGESIZE; )0vU
k
_\PNr.D8
privateList items; o}Odw;
mME4 l
privateint totalCount; n~V4nj&_T
1(zsOeX
privateint[] indexes = newint[0]; FsB^CxVg
,t{,_uPJY
privateint startIndex = 0; )3YtIH_
OdWou|Gz
public PaginationSupport(List items, int xqXDxJlns
SVlua@]ChU
totalCount){ Ok7t@l$
setPageSize(PAGESIZE); Z@8vL
setTotalCount(totalCount); o@]So(9f
setItems(items); o*x*jn:hm
setStartIndex(0); p(xC*KWB
} XoLJ L]+?
6$a$K,dZ
public PaginationSupport(List items, int $WYbm}j
I$NhXZ)KT
totalCount, int startIndex){ a07@C
setPageSize(PAGESIZE); tkQH\5
setTotalCount(totalCount); =~Ynz7 /x
setItems(items); .@-9'<K?~
setStartIndex(startIndex); ML-)I&>tT
} |4mpohX
Cz4)Yz
public PaginationSupport(List items, int KfBTL!0#
_rV 5E
totalCount, int pageSize, int startIndex){ i&njqK!wS
setPageSize(pageSize); >-_d CNZ
setTotalCount(totalCount); id<:p*
setItems(items); IW8+_#d
setStartIndex(startIndex); 7"7rmZ
} cYx4~ V^
)%SkJ
publicList getItems(){ x:vu'A
return items; !3iGz_y
}
rhpPCt
zWpqJK
publicvoid setItems(List items){ e__@GBG
this.items = items; Ftw;Yz
} l$K,#P<)
AM"Nn
L"
publicint getPageSize(){ )&era` e[
return pageSize; Uie?9&3
} O20M[_S
e{;OSk`x
publicvoid setPageSize(int pageSize){ |9"p|6G?B
this.pageSize = pageSize; 7&`}~$>}>e
} +,:du*C
qQpnLV 4
publicint getTotalCount(){ (>mI'!4d
return totalCount; YY?a>j."a
} /&u<TJ4
N=:5eAza
publicvoid setTotalCount(int totalCount){ 0JgL2ayIVI
if(totalCount > 0){ `28};B>
this.totalCount = totalCount; %}86D[PF
int count = totalCount / M
:3u@06a
B!gGK|8
pageSize; $F.([?)k?
if(totalCount % pageSize > 0) ELh8ltLY
count++; -",=G\XZ
indexes = newint[count]; y%sroI('y
for(int i = 0; i < count; i++){ {k4CEt;
indexes = pageSize * r'CM
r1ws1 rr=
i; wU#F_De)R:
} 2L AYDaS
}else{ V`adWXu
this.totalCount = 0; h8\
T
} L=2y57&Y
} QDpEb=|S
as=m`DqOh
publicint[] getIndexes(){ ?[*0+h`en
return indexes; 9Rek4<5
} !-m&U4Ku6o
7&KT0a*
publicvoid setIndexes(int[] indexes){ '(f/~"9B
this.indexes = indexes; 2tROT][J%
} ZKg{0DY
aNyvNEV3C
publicint getStartIndex(){ ^xf<nNF:p
return startIndex; axHK_1N{
} )CX4kPj
C^QtSha
publicvoid setStartIndex(int startIndex){ ,!V]jP)
if(totalCount <= 0) K1V#cB
WO
this.startIndex = 0; Z/^ u
elseif(startIndex >= totalCount) &a/__c/l
this.startIndex = indexes USN8N (
r>jC_7
[indexes.length - 1]; tbnH,*
elseif(startIndex < 0) ~gz^Cdh
this.startIndex = 0; JFgoN,xn
else{ Bl9jkq
]
this.startIndex = indexes tBTTCwNT%
{pb>$G:gfx
[startIndex / pageSize]; /7!""{1\\
} @/r^%G
} 6t/`:OZC:
SI:U0gUc
publicint getNextIndex(){ 8Ld:"Y#
int nextIndex = getStartIndex() + D>Gt]s
!v]b(z`Y
pageSize; AmwWH7,g
if(nextIndex >= totalCount) 4tSv{B/}
return getStartIndex(); 7Cjd.0T=(
else JbB}y'c4}=
return nextIndex; 'qdPw%d
} 2,aPr:]
++L?+^h
publicint getPreviousIndex(){ g%u&Zkevx
int previousIndex = getStartIndex() - Le"oAA#[
syip; ;
pageSize; TO2c"7td
if(previousIndex < 0) v^ d]rSm
return0; Jc)^49Rf
else 9w9jpe#
return previousIndex; )otb>w5
} DO7W}WU
r_EcMIuk
} fw oQ'&
fQLt=Lrp
,@m@S^
A`{y9@h(
抽象业务类 EQqx+J&!
java代码: kY]W
Qu
iCP/P%
CE15pNss
/** VF&Z%O3n
* Created on 2005-7-12 ]pEV}@7
*/ ^\B:R,
package com.javaeye.common.business; a?yMHb{F
yT{8d.Rh
import java.io.Serializable; v#=`%]mL
import java.util.List; ~x{.jn
K^r)CCO
import org.hibernate.Criteria; E,n}HiAz7V
import org.hibernate.HibernateException; x\2?ym@
import org.hibernate.Session; $8l({:*q0
import org.hibernate.criterion.DetachedCriteria; Wlh~)
import org.hibernate.criterion.Projections; ~.%K/=wK @
import `V[!@b:
_=
#zc4U
org.springframework.orm.hibernate3.HibernateCallback; ;Ut+yuy
import $3D'4\X~?
K;7f?52
org.springframework.orm.hibernate3.support.HibernateDaoS o;b0m;~
H'
T
upport; W)(^m},*8D
xf%4, JQ
import com.javaeye.common.util.PaginationSupport; C0=9K@FCb
y}C`&nW[=
public abstract class AbstractManager extends J/7R\;q`~o
e&eW|E
HibernateDaoSupport { 7?OH,^
`RMI(zI3g.
privateboolean cacheQueries = false; m8623DB"
QZ
`tNq :/
privateString queryCacheRegion; 3Rm#-T s
d2X[(3
publicvoid setCacheQueries(boolean V8=Y@T,
C8a*Q"
cacheQueries){ D71;&G]0
this.cacheQueries = cacheQueries; ( *G\g=D
} M.h`&8
6)pH|d.FR
publicvoid setQueryCacheRegion(String T^Ab!O
lCW8<g^
queryCacheRegion){ ~}Z\:#U
this.queryCacheRegion = z9W`FBg
(BX83)
queryCacheRegion; ~f|Z%&l|
} "i:T+#i({O
jQU"Ved
publicvoid save(finalObject entity){ JcJmds
getHibernateTemplate().save(entity); <lr*ZSNY
} H7i$xWs
7\o!HMfK
publicvoid persist(finalObject entity){ H1!iP$1#V
getHibernateTemplate().save(entity); ch5s<x#CE
} >]'yK!a?
K}[>T(0E
publicvoid update(finalObject entity){ cYNJhGY
getHibernateTemplate().update(entity); ,?
E&V_5
} 9iN.3/T8
HG/p$L*
publicvoid delete(finalObject entity){ # N~,F@t
getHibernateTemplate().delete(entity); eMK+X \
} TG
n-7 88
ry};m_BY
publicObject load(finalClass entity, v+6@cC
=Nz0.:
finalSerializable id){ !gwjN_ZJ^
return getHibernateTemplate().load -#-p1^v}
4LI0SwD#^/
(entity, id); >k']T/%
} 66snC{gU
%/kyT%1
publicObject get(finalClass entity, G;gJNK"e
^"8G`B$r
finalSerializable id){ 9Qj2W
return getHibernateTemplate().get {#IPf0O
OEdJc\n_R
(entity, id); ujW1+Oj=~
} fpM#XFj
(_*
wt]"'
publicList findAll(finalClass entity){ A`O <6
return getHibernateTemplate().find("from ]43[6Im
'+<(;2Z
vL
" + entity.getName()); F?Ju??O
} \^*<
y-jL
89o)M5KQ
publicList findByNamedQuery(finalString ')+0nPV
O?bK%P]ay
namedQuery){ &O[s:
return getHibernateTemplate 7#;vG>]
_RMQy~&b
().findByNamedQuery(namedQuery); jdevat,&u
} j-]&'-h}#
ba@ax3
publicList findByNamedQuery(finalString query, x}fn'iUnm
OLq
0V3m
finalObject parameter){ yh;Y,;4
return getHibernateTemplate :ZdUx
~Pk0u{,4XQ
().findByNamedQuery(query, parameter); %R_{1GrL'c
} m$>iS@R
EruP
publicList findByNamedQuery(finalString query, 5IVksg
:lcea6iO
finalObject[] parameters){ E]^5I3=O
return getHibernateTemplate /I&wj^
F-n"^.7
().findByNamedQuery(query, parameters); ]pTvMom$6
} Hr;h4J
&UAe!{E0
publicList find(finalString query){ 5,+\`!g
return getHibernateTemplate().find )J/HkOj"V
ScnY3&rc
(query); toa-Wa{
} %@&a7JOL
jRkC/Lw
publicList find(finalString query, finalObject Mjpo1dw
@b!"joEy
parameter){ WoL9V"]
return getHibernateTemplate().find ']51jabm
#;9H@:N
(query, parameter); `ZHP1uQ<
} g+q@i{Yn
E|Bd>G
public PaginationSupport findPageByCriteria r$)$n&j
;##]G=%
(final DetachedCriteria detachedCriteria){ lXrD!1F
return findPageByCriteria g: %9jf
lHBI
(detachedCriteria, PaginationSupport.PAGESIZE, 0); O]u",J5
} fhp)S",
mAqDjRV1
public PaginationSupport findPageByCriteria sB}]yw
H;_yRUY9
(final DetachedCriteria detachedCriteria, finalint -@%%*YI>
hsce:TB
startIndex){ `LP!D
return findPageByCriteria X\GM/A
(;o*eFC F
(detachedCriteria, PaginationSupport.PAGESIZE, %j]STD.E
f|0lj
startIndex); )@QJ
} ='Oj4T
H;vZm[\0N-
public PaginationSupport findPageByCriteria QrjDF>
Rmh*TQu
(final DetachedCriteria detachedCriteria, finalint Vk<k +=7
[$:,-Q @
pageSize, vd~U@-C=R
finalint startIndex){ :=g.o;(/N
return(PaginationSupport) *c]KHipUIS
<,39_#H?F3
getHibernateTemplate().execute(new HibernateCallback(){ &W_th\%
publicObject doInHibernate 4be> `d5j
MZm'npRf
(Session session)throws HibernateException { ^KHLBSc:
Criteria criteria = -Q[g/%
6OUvrfC(H
detachedCriteria.getExecutableCriteria(session); mVf.sA8
int totalCount = mX_)b>iW
Y^lQX~I2{
((Integer) criteria.setProjection(Projections.rowCount swr"k6;G
2bQ/0?.).-
()).uniqueResult()).intValue(); ")\aJ8
criteria.setProjection eqzTQen8q
=t+ ('
(null);
)5l u.R%
List items = ~@M7&%]
?iSGH'[u
criteria.setFirstResult(startIndex).setMaxResults r%MyR8'k]
A!HK~yk~Q
(pageSize).list(); V:^H4WvL\W
PaginationSupport ps = 9`X&,S~e
u^Sv#K X
new PaginationSupport(items, totalCount, pageSize, }""p)Y&
XeUprN
startIndex); 8=H\?4)()Y
return ps; O k(47nC
} EZAm)5:]A
}, true); wa?+qiWnrl
} ZJXqCo7O
'C]jwxy
public List findAllByCriteria(final ?MZ:_'2p
K+ehr
DetachedCriteria detachedCriteria){ gRvJ.Q {h
return(List) getHibernateTemplate V9jFjc?
26nBBS,;
().execute(new HibernateCallback(){ *FPg#a+
publicObject doInHibernate I)[B9rbe
gduxA/aT
(Session session)throws HibernateException { |HgfV@Han
Criteria criteria = EVz9WY
p$OD*f_b
detachedCriteria.getExecutableCriteria(session); 9eSRCLhgD
return criteria.list(); /RF%1!M
K
} rgR?wXW]jE
}, true); elKx]%k*)
} g~R/3cm4
[t}):}~F|
public int getCountByCriteria(final 2]Fu
1
GVp
DetachedCriteria detachedCriteria){ hmzair3X
Integer count = (Integer) q!*MH/R
c,BAa*]K
getHibernateTemplate().execute(new HibernateCallback(){ '5WN,Vy8.
publicObject doInHibernate i+U51t<
z\$;'
(Session session)throws HibernateException { |0w~P
s
Criteria criteria = 59MR|Jt
Ar~{= X
detachedCriteria.getExecutableCriteria(session); \]a uSO
return \(9p&"Q-
3;D?|E]1
criteria.setProjection(Projections.rowCount 5`yPT>*#m>
}9}w8R~E
()).uniqueResult(); {d}26 $<$]
} f(.6|mPp
}, true); N l|^o{#
return count.intValue(); z|%Bh
} o}!&y?mp
} XPVV+.
g^n;IE$B
w%~qB5wF6
Zjt9vS)
;qG1r@o
V<W02\Hs
用户在web层构造查询条件detachedCriteria,和可选的 [J:zE&aj
ahoh9iJ
startIndex,调用业务bean的相应findByCriteria方法,返回一个 'Z$jBL
5:_~mlfi
PaginationSupport的实例ps。 g\j>qUjs%Q
V%o#AfMI_
ps.getItems()得到已分页好的结果集 u=l0f6W
ps.getIndexes()得到分页索引的数组 r'PE5xqF
ps.getTotalCount()得到总结果数 SNxz*`@4
ps.getStartIndex()当前分页索引 <tU
:U<ea]
ps.getNextIndex()下一页索引 C &FN#B
ps.getPreviousIndex()上一页索引 ZU^Q1}</5
/ (.'*biQ
!r2}59J
=_pmy>_z
.Wh6(LDY(
|WUA1g
dc)wu]
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 J;"nm3[.q
B~BUWWMfp
,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 sFD!7;
s|KfC>#
一下代码重构了。 D~7%};D[
y#nSk%"t"
我把原本我的做法也提供出来供大家讨论吧: w0\4Wa
L&rO6
首先,为了实现分页查询,我封装了一个Page类: -
Ra\^uz
java代码: 'bG1U`v=3
%!D_q~"H
&F9OZMK=
/*Created on 2005-4-14*/
{\F2*P
package org.flyware.util.page; V9gVn?O0
@eA %(C
/** AwA1&mh
* @author Joa )m)h/_
* JJ)y2
*/ K"G(?<>~4c
publicclass Page { f};!m=b
./2Z?,
/** imply if the page has previous page */ ]+FX$+H/A0
privateboolean hasPrePage; #fJwC7 4
KgL<}=S
/** imply if the page has next page */ +i2YX7Of
privateboolean hasNextPage; rR3m'[
pEJ#ad
/** the number of every page */ TIKEg10I
privateint everyPage; fWqv3nY^
}isCvb
/** the total page number */ 8x`Kl(
privateint totalPage; ]kzv8#
1+VY><=n
/** the number of current page */ ]gjr+GV
privateint currentPage; *c!;^Qy p&
aGdpecv
/** the begin index of the records by the current z^YeMe
_95- -\
query */ ;sm"\.jF
privateint beginIndex; q.U*X5
!4i,%Z&6
b*@&c9I;q
/** The default constructor */ 0@JilGk1u
public Page(){ q+r `e
(ej:_w1
} M
,Zm|3L
5~v(AB(x
/** construct the page by everyPage .ou!g&xu
* @param everyPage 8 /5sv
* */
#_?426Wfs
public Page(int everyPage){ EKV+?jj$
this.everyPage = everyPage; ^cfkP(Y3kx
} z(c@(UD-_
s@.`"TF.7
/** The whole constructor */ UZ[/aq
public Page(boolean hasPrePage, boolean hasNextPage, !5yRWMO9X~
dcV,_
~W]#9&yQ
int everyPage, int totalPage, ~R"]LbeY
int currentPage, int beginIndex){ :|*Gnu
this.hasPrePage = hasPrePage; /8 e2dw:
\
this.hasNextPage = hasNextPage; s
ZlJ/_g
this.everyPage = everyPage; OHx,*}N
this.totalPage = totalPage; /&S~+~]n
this.currentPage = currentPage; a!TBk=P
this.beginIndex = beginIndex; 8<E!rn-
} 4r68`<mn[
m~Kch~~]
/** hr)+Pk
* @return :w?:WH?2L
* Returns the beginIndex. i*mZi4URN
*/ >C*?17\
publicint getBeginIndex(){ _"R3N
return beginIndex; )x_W&