Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +Z{4OJK
7rhpIP2n
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T-5T`awf
h+$_:](PC
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 5<#H=A~(
<&+l;z
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Rw.
Uz&
:+R||qi
。 U9N}6a=
W)9KYI9u
分页支持类: ;^
/9sLW?#
RcHyePuF)R
java代码: 2?}(
}%jb/@~
n1cAI|ZE
package com.javaeye.common.util; + S%+Ku
m' aakq
import java.util.List; U2Ur N?T
eg,S(;VEt
publicclass PaginationSupport { Jl9T[QAJn1
f0^s*V+
publicfinalstaticint PAGESIZE = 30; zg5u
&[s^`e
privateint pageSize = PAGESIZE; J#X 7Ss
]XP[tLYY
privateList items; Az)P&*2:'`
MK"Yt<e(o
privateint totalCount; -m+2l`DLy
<4!w2vxG
privateint[] indexes = newint[0]; \?C(fpR
\
_i`=dx
privateint startIndex = 0; eFeeloH?e*
E? FPxs
public PaginationSupport(List items, int Dn6DkD!
^iI^)
totalCount){ :s$9#}hw,
setPageSize(PAGESIZE); %d?%^)
u,
setTotalCount(totalCount); Y&j6;2-Z
setItems(items); ;bA9(:?
setStartIndex(0); $h$+EE!
} p(U'Ydl~
@E==~ b
public PaginationSupport(List items, int 3s|tS2^4
-({\eL$n
totalCount, int startIndex){ 95H`-A
setPageSize(PAGESIZE); $OUa3!U_!
setTotalCount(totalCount); <&x_e-;b'
setItems(items); QOP*vH >J
setStartIndex(startIndex); tq*Q|9j7VG
} _@@S,(MA
n@%'Nbc>b
public PaginationSupport(List items, int 8l}|.Q#--
xApa+j6I
totalCount, int pageSize, int startIndex){ ae^xuM?7
setPageSize(pageSize); c{852R
setTotalCount(totalCount); Y8AU<M
setItems(items); %V+,#
setStartIndex(startIndex); Us%VBq
} /g8yc'{p
:]//{HF
publicList getItems(){ dIf Jr}ih
return items; vw(};)8
} s0`uSQ2X
IBuuZ.=j2h
publicvoid setItems(List items){ .*zQ\P
this.items = items; AG9U2x
} BShZ)t
A l` ;SWN
publicint getPageSize(){ B"EMir'
return pageSize; `n %~#TJ
} ~M\s!!t3
J*;t{M5
publicvoid setPageSize(int pageSize){ v |i(peA#
this.pageSize = pageSize; PNKmI
} 5q)Eed
{<]abO
publicint getTotalCount(){ :WxMv~e{U
return totalCount; KS|$_-7u
} /stED{j,
,{oANqP
publicvoid setTotalCount(int totalCount){ `#(4K4]1.
if(totalCount > 0){ l,/5$JGnk
this.totalCount = totalCount; JZ<O-G+
int count = totalCount / @vv`86bm
UtWoSFZ'o!
pageSize; !BY=HFT
if(totalCount % pageSize > 0) AX&1-U
count++; Z@h]dU5%a
indexes = newint[count]; My[L3KTTp
for(int i = 0; i < count; i++){ O-G@To3\
indexes = pageSize * iA < EJ
eR}d"F4W
i; RM`8P5i]sF
} O/<jt'
}else{ V]<dh|x
this.totalCount = 0; lS,Hr3Lz
} c'(]n]a%
} j[z\p~^
\Js9U|lY
publicint[] getIndexes(){ =X1$K_cN
return indexes; $DQ
-.WI
} #uH1!UQb
Y# lE
publicvoid setIndexes(int[] indexes){ #?-W.
this.indexes = indexes; #F9$"L1Hg
} *&U9npN
T0SD|'
publicint getStartIndex(){ Z$pR_dazU
return startIndex; /R,/hiKx\
} x##Iv|$
{:rU5 !n
publicvoid setStartIndex(int startIndex){ ())|x[>JS+
if(totalCount <= 0) oZ=e/\[K
this.startIndex = 0; G)putk@
elseif(startIndex >= totalCount) r&H>JCRZ<=
this.startIndex = indexes ^]v}AEcmW
%]
Bb;0G
[indexes.length - 1]; l >O]Cpt
elseif(startIndex < 0) "w A8J%:
this.startIndex = 0; Z>{8FzP.F
else{ cg$~.ytPK
this.startIndex = indexes C{'c_wX
!^N/n5eoz
[startIndex / pageSize]; !#X^nlc
} F6 UOo.L)I
} !",@,$
CZuxH
publicint getNextIndex(){ Ii
K&v<(]
int nextIndex = getStartIndex() + =DqGm]tA
2AlLcfAW
pageSize; cAL&>T
if(nextIndex >= totalCount) [oYe/<3
return getStartIndex(); \myj Y
else P EbB0GL
return nextIndex; KL|B| u
}
8!T^KMfz
kg-%:;y.
publicint getPreviousIndex(){ YZnrGkQ
int previousIndex = getStartIndex() - c#rbyx?5
7IvCMb&%R
pageSize; PffwNj/l
if(previousIndex < 0) K'71uW>
return0; L@+j8[3BX
else ^L[Z+7|
return previousIndex; -OziUM1qs
} fZGKVxo"
)pzXC
} &556 ;l
3$RII-}>
|6uEf/*DX
cJty4m-
抽象业务类 Y /wvn8~C
java代码: jRBx7|ON
Mr&]RTEE
gNO$WY^
/** ;Lu}>.t
* Created on 2005-7-12 9\"~ G)
*/ Mc\lzq8\ 1
package com.javaeye.common.business; EdU3k'z$
6Qo6T][
import java.io.Serializable; ,%:`Ll
t]$
import java.util.List; -Pvt+I>
{=(4
import org.hibernate.Criteria; q6,xsO,+
import org.hibernate.HibernateException; qItI):9U
import org.hibernate.Session; ,<[os
import org.hibernate.criterion.DetachedCriteria; a`{'u)@
import org.hibernate.criterion.Projections; ;1y\!f3#V~
import z,NHH):~
O_:Q#
org.springframework.orm.hibernate3.HibernateCallback; 3C[ ;2
import $iB(N ZV
q&wMp{
org.springframework.orm.hibernate3.support.HibernateDaoS `SU;TN0
AHLDURv
upport; !YoKKG~_0
"5e]-u'
import com.javaeye.common.util.PaginationSupport; YvU#)M_h
&iSQ2a!l8b
public abstract class AbstractManager extends Mu:H'$"'H
C=Zuy^
HibernateDaoSupport { >LNl8X:Cz*
FKzqJwT
privateboolean cacheQueries = false; T<ua0;7
y"]> Rr
privateString queryCacheRegion; .K0BK)axO
ZuE0'9
publicvoid setCacheQueries(boolean .3Ap+V8?
SnXLjJe
cacheQueries){ @e slF
this.cacheQueries = cacheQueries; I4)vJ0
} Obd!
<6`,)(dj
publicvoid setQueryCacheRegion(String ?@u
&3/&
!]`]67lC
queryCacheRegion){ Zdak))7
this.queryCacheRegion = d#W[<,
Ylf 6-FbF
queryCacheRegion; D~{)\;w^!
} \jfW$TtZm
jXdn4m/O
publicvoid save(finalObject entity){ E85 03
getHibernateTemplate().save(entity); l%)XPb2$J
} kxO$Uk&TX
:Rq D0>1
publicvoid persist(finalObject entity){ *[jaI-~S
getHibernateTemplate().save(entity); m]%cNxS
} |[V(u
=];FojC6I
publicvoid update(finalObject entity){ (Hsfrc
getHibernateTemplate().update(entity); .!`j3W]
} ^.4<#Qs
NfSe(rd
publicvoid delete(finalObject entity){
D?E5p.!A
getHibernateTemplate().delete(entity); Wl,yznT
} Xu
T|vh
a(
qw
publicObject load(finalClass entity, G%P]qi
1n,JynJ
finalSerializable id){ 6-^+btl)#
return getHibernateTemplate().load Oll\T GXP!
VOiphw`
(entity, id); Zw3|HV(so
} ;xRyONt
cEN^H
publicObject get(finalClass entity, Z]6D0b
oDRNM^gz
finalSerializable id){ }`eeIt I+
return getHibernateTemplate().get
1|`9Hp6
&Y,Rm78
(entity, id); Z# :Ww
} 1-,l|K
)Y:CV,`
publicList findAll(finalClass entity){ z6Hl+nq B
return getHibernateTemplate().find("from #a0 (Wh7
<k)rfv7
" + entity.getName()); "#OmmU<U
} abF_i#
lyT~>.?{
publicList findByNamedQuery(finalString 2{%BQq>C
3sL#_@+yz
namedQuery){ [~;9Mi.XL
return getHibernateTemplate h?SUDk:2^
-@QLE}~k[
().findByNamedQuery(namedQuery); ^WRr "3
}
[g/g(RL
H<q:+
publicList findByNamedQuery(finalString query, ,JjTzO
r"4:aKF>
finalObject parameter){ $V+ze*ra
return getHibernateTemplate T|=8jt,
E;X'.7[c
().findByNamedQuery(query, parameter); 1\3n
} 7+z%O3k'I
)i?wBxq'MA
publicList findByNamedQuery(finalString query, rzex"}/ly
?$gEX@5h
finalObject[] parameters){ Axcm~!uf
return getHibernateTemplate i\3`?d
;\H2U.
().findByNamedQuery(query, parameters); -W oZwqh
} 'Kq%tM26!
&^Xm4r%u_
publicList find(finalString query){ 4}0s^>R
return getHibernateTemplate().find a]Lr<i8#%
0)nU[CY
(query); )cvC9gt
} 3}sd%vCK
APF-*/K?
publicList find(finalString query, finalObject m!PN1$9V
@Pa ;h
parameter){ 5bAy@n
return getHibernateTemplate().find !W6]+
[#.QDe
(query, parameter); tIRw"sz
} BeVQ[
a~{mRh
public PaginationSupport findPageByCriteria r..Rh9v/=E
HWc=.Qq
(final DetachedCriteria detachedCriteria){ uYs+xX_
return findPageByCriteria *f,EDSN1@d
+DU}f;O8v
(detachedCriteria, PaginationSupport.PAGESIZE, 0); =T+<>/[
} jbG #__#_
BO1Mz=q
public PaginationSupport findPageByCriteria /6f$%:q
z7GLpTa
(final DetachedCriteria detachedCriteria, finalint DQE.;0ld
-m-~
startIndex){ gXF.e.uU
return findPageByCriteria P ^D\znvc
No h*1u*
(detachedCriteria, PaginationSupport.PAGESIZE, h<}4mo_$
^c/.D*J[I
startIndex); -ERDW Y
} JWEqy+,Fjw
HtXzMSGo7
public PaginationSupport findPageByCriteria $cYh X^YG.
:V >Z|?[*H
(final DetachedCriteria detachedCriteria, finalint Q.!D2RZc
6 s*#y[$
pageSize, =i `o+H
finalint startIndex){ oo/#]a
return(PaginationSupport) n}YRE`>D
r% qgLP{v
getHibernateTemplate().execute(new HibernateCallback(){ []'BrG)!
publicObject doInHibernate Xo'_|-N+
0(64}T)
(Session session)throws HibernateException { 3Hr ZN+D
Criteria criteria = tNq~M
]r|X[9
detachedCriteria.getExecutableCriteria(session); SkS
vu}
int totalCount = Id9hC<8$dq
teET nz_L
((Integer) criteria.setProjection(Projections.rowCount N 0`)WLW
7=}`"7i~
()).uniqueResult()).intValue(); Y68oBUd_E
criteria.setProjection g"F vD_
IY+P Yad
(null); +$P0&YaQ
List items = n)[{nkS6[
2 y,f
criteria.setFirstResult(startIndex).setMaxResults yv&&x.!.Z
Fd0R?d
(pageSize).list(); O$KLQ '0"n
PaginationSupport ps = t}]=5)9<
'(~+
\
new PaginationSupport(items, totalCount, pageSize, +1_NB;,e
"*<9)vQ6|
startIndex); LKTIwb>
return ps; }ob#LC,
} IL&Mf9m
}, true); *ewE{$UpK
} yX/ 9jk
jsjH.O
public List findAllByCriteria(final L_Ff*
e![n$/E3R
DetachedCriteria detachedCriteria){ 8|HuxE
return(List) getHibernateTemplate }H\wed]F/
M2{{B^*$6
().execute(new HibernateCallback(){ ]~GwZB'M
publicObject doInHibernate )} tI8
Il,2^54q
(Session session)throws HibernateException { h#B%'9r
Criteria criteria = ,A4v|]kq]
+ C aPF
detachedCriteria.getExecutableCriteria(session); 3Oy?_a$
return criteria.list(); ]*D=^kA0[
} IyOb0WiEj
}, true); 8.bdN]zn
} lEh; MJ
4Un (}P'
public int getCountByCriteria(final S&q@M
Mnc9l ^
DetachedCriteria detachedCriteria){ JN,4#,
Integer count = (Integer) ^cn%]X#.
+coVE^/w
getHibernateTemplate().execute(new HibernateCallback(){ .]JGCTB3
publicObject doInHibernate `$Z:j;F
C%vR!Az
(Session session)throws HibernateException { %
tT L
Criteria criteria = Q9Sh2qF^2
")}^\Om
detachedCriteria.getExecutableCriteria(session); xk7MMRb
return iz.J._&
;=fOyg
criteria.setProjection(Projections.rowCount Op0n.\>
p(=}Qqdr8
()).uniqueResult(); 5<^$9('
} C8W#$a
}, true); oc7&iL
return count.intValue();
aJdd2,e
} H,u {zU')
} %-1-y]R|
m:SG1m_6
VKqIFM1b
#ue WU
oR}cE
Sr
i&= I5$
用户在web层构造查询条件detachedCriteria,和可选的 Pqu]?X
> mk>VM
startIndex,调用业务bean的相应findByCriteria方法,返回一个 (E[c-1s
]Dec/Nnj
PaginationSupport的实例ps。 y(^t &tgjS
:7>oFz
ps.getItems()得到已分页好的结果集 42]hX9E
ps.getIndexes()得到分页索引的数组 T+1:[bqK
ps.getTotalCount()得到总结果数 xq$(=WPI
ps.getStartIndex()当前分页索引 `ECY:3"$KA
ps.getNextIndex()下一页索引 {%Cb0Zh
ps.getPreviousIndex()上一页索引 Vq-W|<7C=
<hkSbJF
Lz6b9W
B>C+qj@
=S+*=j A
Z(F['Zf
M~+}ss
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 xP/?E
VW&EdrR,S
,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 )cP&c=
JPO'1D)
一下代码重构了。 .Q!_.LX
EmG':K(
我把原本我的做法也提供出来供大家讨论吧: Zaime
,=>Ws:j
首先,为了实现分页查询,我封装了一个Page类: Z mVw5G
q
java代码: ` `mnk>/
K-,4eq!
X(Z~oGyg
/*Created on 2005-4-14*/ b'r</ncZ
package org.flyware.util.page; *yl?M<28
#z6[8B
/** G`D rY;
* @author Joa x%_VzqR`
* =
y@*vl
*/ aQ.QkMZ
publicclass Page { p>oC.[:4a
#ME!G/
/** imply if the page has previous page */ Fc&3tw"g
privateboolean hasPrePage; d?ru8
`D-P}hDm!
/** imply if the page has next page */ 2JdzeJb
privateboolean hasNextPage; S@Iza9\|@
A>\5fO
/** the number of every page */ 4t
5i9+h
privateint everyPage; |VX )S!
&u+l`F^Z
/** the total page number */ VdL*"i
privateint totalPage; ~ECIL7,
=e)t,YVm
/** the number of current page */ C]EkVcKFA
privateint currentPage; *c<6 Er>s
OI^??joQ
/** the begin index of the records by the current ^ YOCHXg
!),eEy
query */ v*";A
privateint beginIndex; ;NMv>1fI
!MXn&&e1
LUs)"ZAi|
/** The default constructor */ /9pN.E
public Page(){ =fRC$
O*7vmPy
} %g_)_ ~
8KyRD1 (-R
/** construct the page by everyPage TUBpRABH
* @param everyPage {=%,NwPs
* */ aP$it6Z
public Page(int everyPage){ nnOgmI7
this.everyPage = everyPage; 8TBv~Qu
} efr 9
Rtu"#XcBw+
/** The whole constructor */ n!-]f.=P
public Page(boolean hasPrePage, boolean hasNextPage, 6&
(b L<8b
dAWB.#
KS'n$
int everyPage, int totalPage, ;FGS(.mjlC
int currentPage, int beginIndex){ c>Tf@Aog>
this.hasPrePage = hasPrePage; UY6aD~tD0
this.hasNextPage = hasNextPage; 2U|"]tpM&
this.everyPage = everyPage; f\;w(_
this.totalPage = totalPage; Z=9<esx
this.currentPage = currentPage; nR]*RIp5
this.beginIndex = beginIndex; v<@3&bot
} F;bkV}^
GaCRo7
/** 7{Lp/z%r
* @return o:'@|(&