Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 p5rq>&"
+(Hp ".gU
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 jHT^I
as
!_+FuF"@
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 aW_Y
Edc3YSg%;
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 PfYeV/M|
CEkf0%YJ
。 bhDqRM
*>aVU'
分页支持类: a%m>v,
9`qw,X&AK_
java代码: PY4">~6\i
j."V>p8u$
(oCpQDab@
package com.javaeye.common.util; WUYU\J&q3
.0/"~5
import java.util.List; bly `mp8#
!}mM"|<
publicclass PaginationSupport { d+h~4'ebv
!RLXB$@`
publicfinalstaticint PAGESIZE = 30; DV?c%z`YO
StNA(+rT
privateint pageSize = PAGESIZE; 3^H-,b0^
6e,IjocsB
privateList items; :`BG/
s 64@<oU<"
privateint totalCount; .pxUO3g
0"\js:-$
privateint[] indexes = newint[0]; 5<KBMCn
rx#GrV*y
privateint startIndex = 0; C@XnV=J
IWddJb~hu
public PaginationSupport(List items, int 66WJ=?JV
'g<FL`iP
totalCount){ AKLFUk
setPageSize(PAGESIZE); Y!c7P,cZ+3
setTotalCount(totalCount); `}
'o2oZnG
setItems(items); %dd B$(
setStartIndex(0); 1,P2}mYv
} UBnHtsM
HN;f~EQT
public PaginationSupport(List items, int P|f h4b4
e9k$5ps
totalCount, int startIndex){ ?6\A$?
setPageSize(PAGESIZE); @v6{U?
setTotalCount(totalCount); {9F}2
SJ
setItems(items); PM:u~D$Jd
setStartIndex(startIndex); 0LHge7482
} 6h[fk.W_
:Ef$[_S>
public PaginationSupport(List items, int W-1Ub |8C
9-=kVmT&g
totalCount, int pageSize, int startIndex){ zLS?:yq
setPageSize(pageSize); h!Fh@%
setTotalCount(totalCount); U6nC
<3f
F
setItems(items); KAT^v bR
setStartIndex(startIndex); ll"6KI'X
} KAy uv
/T&+vzCF
publicList getItems(){ 4kNSF
return items; S6yLq|W0
} @, z4{B
q"g4fzCD
publicvoid setItems(List items){ .'1]2/ad
this.items = items; O~Dm|hP
} We"\nOP
l2!ztK1^
publicint getPageSize(){ !*k'3rKOW
return pageSize; `LTD|0;
} i~DLo3
Ao9=TC'v$'
publicvoid setPageSize(int pageSize){ Zqg
AgN@
this.pageSize = pageSize; bwjLMWEVq
} t/x]vCP,2D
b]Lp_t
publicint getTotalCount(){ :7qJ[k{g
return totalCount; >hotkMX `3
} }"^d<dvuz
~X) 1!Sr
publicvoid setTotalCount(int totalCount){ 6,p;8I
if(totalCount > 0){ /-ewCCzZV
this.totalCount = totalCount; Pz' Zn
int count = totalCount / F
n*+uk
g3'yqIjQL
pageSize; >ufN[ab
if(totalCount % pageSize > 0) GtqA@&5&
count++; c#[d7t8ONe
indexes = newint[count]; g.Kyfs4`
for(int i = 0; i < count; i++){ !xC IvKW
indexes = pageSize * c=:A/z{
_ba.oIc
i; 4':U rJ+
} N2EX`@_2
}else{ GmN~e*x>p
this.totalCount = 0; m&6I@S2
} BMbZ34^e
} W^9=z~-h
HO8x:2m
publicint[] getIndexes(){ kkV*#IZ
return indexes; Z9I
?j1K|!
} .|J-(J<>[.
vau#?U".}>
publicvoid setIndexes(int[] indexes){ 4g/Ly8
this.indexes = indexes; p@=B\A]
} ==W] 1@s
[iG4qI
publicint getStartIndex(){ URxy*)
return startIndex; {F$MZ2 E
} G c:oSvm
&G!2T!xx
publicvoid setStartIndex(int startIndex){ MB(l*ju0
if(totalCount <= 0) ! lm0zR
this.startIndex = 0; oIY@xuj
elseif(startIndex >= totalCount) ca!x{,Cvnj
this.startIndex = indexes naW!Mga
v0~*?m4
[indexes.length - 1]; @{^6_n+gT%
elseif(startIndex < 0) :e TzjW=
this.startIndex = 0; 'ul~f$
V
else{ (L8z<id<z
this.startIndex = indexes O(44Dy@2
JclG*/Wjg4
[startIndex / pageSize]; zlN<yZB^
} 9y&&6r<I
} #-FfyxQ8ai
VTJ,;p_UH
publicint getNextIndex(){ 9|LV
x3]
int nextIndex = getStartIndex() + 8#~x6\!b
Z<Ke/Xi
pageSize; gK"E4{y_@
if(nextIndex >= totalCount) JNgl
return getStartIndex(); rXg#_c5j
else %N-f9o8
return nextIndex; UkXf)
} km#Rh^
oSqkAAGz\
publicint getPreviousIndex(){ "':u#UdS
int previousIndex = getStartIndex() - C{Er%
O'<cEv'B*
pageSize; g_t1(g*s
if(previousIndex < 0) SAw. 6<Wy-
return0; l?LP:;S
else Lr`G. e
return previousIndex; El`f>o+EJ
} -_|U"C$
i\u m;\
} cv/
k'$UA$2d
`}9j vR5
h\qM5Qx+Q
抽象业务类 SPK%
' s
java代码:
)\r;|DN
d|(@#*{T]
-&\?Q_6
/** a8!/V@a
* Created on 2005-7-12 N=P+b%%:Z
*/ F`\7&'I
package com.javaeye.common.business; ZI'Mr:z4
A#B6]j)
import java.io.Serializable; 34\:1z+s M
import java.util.List; u|a+:r)*4
<[mvfw
import org.hibernate.Criteria; i=G.{.
import org.hibernate.HibernateException; $f^ \fa[
import org.hibernate.Session; 6S2v3
import org.hibernate.criterion.DetachedCriteria; v"dj%75O?e
import org.hibernate.criterion.Projections; ;\Vi~2!8
import /_MEb42&
cfEi]
org.springframework.orm.hibernate3.HibernateCallback; 2m/=0sb\{
import 'v*Y7zZ#K
.U:D uyT
org.springframework.orm.hibernate3.support.HibernateDaoS [J.-gN$X@
hhVyz{u
upport; m;"i4!
=9ISsI\Y6
import com.javaeye.common.util.PaginationSupport; D.\s mk
:{Crc
public abstract class AbstractManager extends fhZD[m#D
;0f?-W?1
HibernateDaoSupport { 'YcoF;&[C
gqf*;Z eU
privateboolean cacheQueries = false; (X"WEp^Q{I
Gf{FFIe(
privateString queryCacheRegion; g^EkRBU
^KK6 d
publicvoid setCacheQueries(boolean _jW}p-j
H,!3s<1
cacheQueries){ ?!J{Mrdn
this.cacheQueries = cacheQueries; m
pWmExQ
} K8UgP?c;0
elBmF#,j7
publicvoid setQueryCacheRegion(String _g(4-\
YQI&8~z
queryCacheRegion){ T]%:+_,
this.queryCacheRegion = phA^ kdW
$m;rOKVU
queryCacheRegion; KF[P
/cFI
} MH>CCT
>dW~o_u'QN
publicvoid save(finalObject entity){ i$A0_ZJKjZ
getHibernateTemplate().save(entity); 0V&6"pF_Y'
} ]`2=<n;=
62 biOea
publicvoid persist(finalObject entity){ u-a* fT
getHibernateTemplate().save(entity); ;(0E#hGN
} :/kz*X=<
c?NXX&
publicvoid update(finalObject entity){ zl W5$cC[
getHibernateTemplate().update(entity); -nQ :RHnd
} d|9B3I*I
Lit@ m2{\
publicvoid delete(finalObject entity){ V.RG=TVS
getHibernateTemplate().delete(entity); :Sx!jx>W
} av&4:O!
_[,oP s:+
publicObject load(finalClass entity, :-=,([TJ
]KS|r+
finalSerializable id){
=jX'FNv#
return getHibernateTemplate().load APgP*,
,rB"ag !
(entity, id); =?}
t7}#
} S[bFS7[
4&Uq\,nx
publicObject get(finalClass entity, ]Hp o[IF
e7<//~W7W
finalSerializable id){ )|88wa(M
return getHibernateTemplate().get U`D.cEMfH
Ri@`sc{n
(entity, id); KrhAObK
} cC.=,n
^ $M@yWX6
publicList findAll(finalClass entity){ asDq(J`sQ
return getHibernateTemplate().find("from GT[,[l
wL'tGAv
" + entity.getName()); ?qeBgkL(B^
} KKR@u(+"a
,r{[l D^
publicList findByNamedQuery(finalString Im;8Abf
}U=|{@%
namedQuery){ zDbjWd
return getHibernateTemplate 6t0!a@t
bqwQi>^Cw
().findByNamedQuery(namedQuery); HSk gS
} =_%i5]89P
EK^B=)q6:W
publicList findByNamedQuery(finalString query, j +j2_\
uaMf3HeYV
finalObject parameter){ =#N;ZG
return getHibernateTemplate c?qg
i"kS
jXEuK:exQ
().findByNamedQuery(query, parameter); sp4J%2b
} -e"~UDq`
yub|
publicList findByNamedQuery(finalString query, D|W^PR:@h
mC
P*v-
finalObject[] parameters){ $2uZdl8Rvj
return getHibernateTemplate
>:whNp
"HRoS#|\
().findByNamedQuery(query, parameters);
uqy b
} M{U {iS
J`U\3:b`SP
publicList find(finalString query){ X|'E yZ
return getHibernateTemplate().find |=C&JA
P@ewr}
(query); @add'>)
} Ju""i4
EP.nVvuL
publicList find(finalString query, finalObject `I(#.*
SF.4["$
parameter){ s)#8>s -
return getHibernateTemplate().find {{b&l!
RbUhLcG5
(query, parameter); C9-IJj
} _jV(Gv'
jtdhdA
public PaginationSupport findPageByCriteria N;cEf7+f
]UG+<V
,:
(final DetachedCriteria detachedCriteria){ p`//
*gl
return findPageByCriteria Byf5~OC
pyEi@L1p
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 2ZMYA=[!
} W=v4dy]B
f\sxx!kt
public PaginationSupport findPageByCriteria wYtL1D(
`=A*ei5
(final DetachedCriteria detachedCriteria, finalint c+l1#[Dnc
DPuz'e*
startIndex){ _qg)^M 6
return findPageByCriteria *={`
%
hLyD#XCFA
(detachedCriteria, PaginationSupport.PAGESIZE, 6Q<^,`/T
[AzQP!gi
startIndex); i{8T 8
} r<]Db&k
M)Iu'
public PaginationSupport findPageByCriteria aRBTuLa)fo
}`g:)gJ
(final DetachedCriteria detachedCriteria, finalint ?{s!.U[T@
xOCHP|?
pageSize, OhmKjY/}
finalint startIndex){ % AqUVt9}
return(PaginationSupport) "mbcZ5_
x{Y}1+Y4
getHibernateTemplate().execute(new HibernateCallback(){ s hbPy
publicObject doInHibernate Nz`4q%+
S<"M5e
(Session session)throws HibernateException { *I;,|Jj k
Criteria criteria = 6Z~u2&
Txkmt$h
detachedCriteria.getExecutableCriteria(session); ^,L vQW4
int totalCount = H"|xG;cf
82%~WQnS
((Integer) criteria.setProjection(Projections.rowCount #s JE{Tb
p[BF4h{E
()).uniqueResult()).intValue();
kt8P\/~*i
criteria.setProjection V[-4cu,Ph^
^06f\7A
(null); w9I7pIIl
List items = IYm~pXg^0
%{\|/#>:
criteria.setFirstResult(startIndex).setMaxResults k0IW,z%
1:<= zqh0
(pageSize).list(); 4`F(RweGx
PaginationSupport ps = ;D^%)v/i
?Xm!;sS0
new PaginationSupport(items, totalCount, pageSize, 8H4"mxO
Jx;"@
startIndex); o:ki IZ]
return ps; ~F8M_
} `IQ01FuP
}, true); -"qw5Y_oF?
}
7;dTQ.%n
y9d[-j
;w
public List findAllByCriteria(final mA|&K8H
y:Xs/RS
DetachedCriteria detachedCriteria){ L/1zG/@
return(List) getHibernateTemplate 5urM,1SQ@
wjk-$p
().execute(new HibernateCallback(){
'Eds0"3
publicObject doInHibernate {@Y|"qIN
h8;B +#f`
(Session session)throws HibernateException { 6~8A$:
Criteria criteria = 1{N73]-M:
Wx#((T
detachedCriteria.getExecutableCriteria(session); 70NQ9*AAy
return criteria.list(); ~[|&)}q
} Zw+VcZz3
}, true); ( lbF/F>v
} c"BFkw
m(QGP\Ya
public int getCountByCriteria(final :0,q>w
( zQ)EHRD
DetachedCriteria detachedCriteria){ [:gPp)f,
Integer count = (Integer) v3|-eWet^
;-p1z%
u
getHibernateTemplate().execute(new HibernateCallback(){ SH>L3@Za
publicObject doInHibernate Az4+([
nU]n]gd
(Session session)throws HibernateException { 9{{QdN8
Criteria criteria = 2N_8ahc
=}N&c4I[j
detachedCriteria.getExecutableCriteria(session); Gt4| ]
return K#bd b
$o
rN>M42
criteria.setProjection(Projections.rowCount ^'EeJN
,"?h_NbF
()).uniqueResult(); ?>b>LDpx?
} L><# I
}, true); WP, Ll\K)7
return count.intValue(); {awv=s
} .`Ey'T_
} ?sQOz[ig;
;,T3C:S?
tpe:]T/xh
*,$cW,LN
j^ L"l;m
MhMY"bx8
用户在web层构造查询条件detachedCriteria,和可选的 )cA#2mlS'1
Jy&O4g/'5
startIndex,调用业务bean的相应findByCriteria方法,返回一个 [{.e1s<EK
Q 6djfEN>
PaginationSupport的实例ps。 gL%%2 }$
zjVBMqdD
ps.getItems()得到已分页好的结果集 *Ag</g@ h
ps.getIndexes()得到分页索引的数组 AR9D;YfR~
ps.getTotalCount()得到总结果数 j)4:*R.Z]
ps.getStartIndex()当前分页索引 +_Nr a
ps.getNextIndex()下一页索引 ,ra!O=d~0
ps.getPreviousIndex()上一页索引 ~jdvxoX-
a12Q/K
m0xL'g6F
6*`KC)a
6&~8TH
qEvHrsw},
Rh!B4oB4
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 MfNxd
6w
.!uXhF'
,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(*yAe(
O;RsYs9
一下代码重构了。 +X[+SF)!
o&]b\dV
我把原本我的做法也提供出来供大家讨论吧: t']d_Vcza
L ]HtmI
首先,为了实现分页查询,我封装了一个Page类: ovv<7`
java代码: %LBa;M
S/YT
V
j#^EZ/
/*Created on 2005-4-14*/ O$QtZE61
package org.flyware.util.page; U5 X\RXy~
*1FDK{
/** Rf *we+
* @author Joa RTN?[`
* l1 (6*+
*/ 0vN <0
publicclass Page { zrt \]h+
o+UCu`7e
/** imply if the page has previous page */ +O`3eP`u
privateboolean hasPrePage; 7.7aHt0
~>C@n'\lv
/** imply if the page has next page */ hY$gzls4
privateboolean hasNextPage; L?~>eT
12
y=Eh
/** the number of every page */ Dq=&K,5;
privateint everyPage; }DH3_M!
}^|g|xl!
/** the total page number */ uTsxSkHb/
privateint totalPage; s"u6po.'
[
j'L*j
/** the number of current page */ HgH\2QL3&
privateint currentPage; 4n55{?Z
j\W"P_ dpd
/** the begin index of the records by the current e/+_tC$@p@
3khsGD@
query */ l&rS\TCkp
privateint beginIndex; pq8XCOllXx
;U7o)A;
9a\H+Y~
/** The default constructor */ b1rW0}A
public Page(){ tC;LA 4
O~3<P3W
} <sU?q<MC
BE,XiH;
/** construct the page by everyPage ?`9XFE~a!
* @param everyPage Y"Y%JJ.J
* */ W 7xh
public Page(int everyPage){ zNAID-5K;
this.everyPage = everyPage; h"~i&T
h
} NifD
pqjgt
jA<(#lm;
/** The whole constructor */ 3y&N}'R(F
public Page(boolean hasPrePage, boolean hasNextPage, M%(B6};J
UB%Zq1D|t
_=%F6}TE
int everyPage, int totalPage, 2o8:[3C5
int currentPage, int beginIndex){ OS$}ej\
this.hasPrePage = hasPrePage; 6I)[6R
this.hasNextPage = hasNextPage; 0tA~Y26
this.everyPage = everyPage; ?vA)F)MS
this.totalPage = totalPage; P
X9GiJN "
this.currentPage = currentPage; d|I_SI1
this.beginIndex = beginIndex; x9l l 0Ht
} TA2HAMx)
VO"/cG;]*
/** 6JrwPZB
* @return ALcin))+B
* Returns the beginIndex. ]~a;tF>Fw
*/ &%@e6..Ex
publicint getBeginIndex(){ rV{:'"=y-
return beginIndex; l=|>9,La
} }%8 :8_Ke
@=
E~`
/** E[$"~|7|$
* @param beginIndex @`Fv}RY{
* The beginIndex to set. '=s{9lxn^
*/ HgGwV;W
publicvoid setBeginIndex(int beginIndex){ *lZ;kW(}p
this.beginIndex = beginIndex; ^pB}eh.@U
} fL xGaOT
W4OL{p-\/
/** Uu_g_b:z
* @return 9Wu c1#
* Returns the currentPage. pyHU+B
*/ 3o_)x
publicint getCurrentPage(){ _\/KI
/
return currentPage; GGM|B}U p
} ppm=o4`s[
_sp,,gz
/** ;s*
* @param currentPage jF$bCbAUce
* The currentPage to set. z6IOVQ*r
*/ [Sr^CYP(
publicvoid setCurrentPage(int currentPage){ ?g{--'L
this.currentPage = currentPage; A&?8 rc
} eeVDU$*e=
/"+CH\)
E
/** 8ln{!,j;
* @return UC
e{V ]T
* Returns the everyPage. *|gY7Av*
*/ HbI'n,+
publicint getEveryPage(){ 7`s*
{
return everyPage; <wH"{G3?
} <USK6!-G
"U"phLX
/** x/fhlf}a}=
* @param everyPage gg0rkg
* The everyPage to set. -gQtw%
`x
*/ T}}T`Ce
publicvoid setEveryPage(int everyPage){ kk`K)PESi
this.everyPage = everyPage; ^l:~r2
} `w6*(t:T
(HEi;
/** 3 as~yF0
* @return opXxtYC@
* Returns the hasNextPage. d/8p?Km
*/ "|Ke/0rGB
publicboolean getHasNextPage(){ f};RtRo2
return hasNextPage; _2-fH
} *5QN:
f7lt|.p
/** =:M/hM)#
* @param hasNextPage QGCg~TV;
* The hasNextPage to set. *M? [Gro/
*/ \?D~&d,a=
publicvoid setHasNextPage(boolean hasNextPage){ oW5Ov
this.hasNextPage = hasNextPage; 70GwTK.{~
} =.`:jZG
|Q(3rcOrV"
/** pqCp>BO?O
* @return xA'RO-a}h
* Returns the hasPrePage. :'
=le*h
*/ ptc.JB6
publicboolean getHasPrePage(){ } =p e;l
return hasPrePage; n#l~B@
} Bq5-L}z
9bQD"%ha=d
/** {X\%7Zef+
* @param hasPrePage Zg*XbX
* The hasPrePage to set. a'%eyN
*/ en_W4\7^
publicvoid setHasPrePage(boolean hasPrePage){ ]+k]Gbty6
this.hasPrePage = hasPrePage; R?3N><oh*
} c
W1`[b
j].=,M<dxE
/** Gw$Y`]ipy
* @return Returns the totalPage. 4wkmgS
* mP ]a}[
*/ cq`!17"k
publicint getTotalPage(){ uv&4
A,h
return totalPage; c(kYCVc
} 8 7z]qE
b}3t8?wG&
/** "C.cU
* @param totalPage )Z*nm<=
* The totalPage to set. N;HG@B!m
*/ -kP$S qR~
publicvoid setTotalPage(int totalPage){ X:/7#fcG8
this.totalPage = totalPage; 1)H;}%[
} FvJkb!5*e_
cCuK?3V4K
} O@>ZYA%
&R))c|>OT&
/ M@[ 8
IkuE |
v@d]*TG
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 <^w4+5sT/
OJ1MV 7&
个PageUtil,负责对Page对象进行构造: 9'=ZxV
java代码: K]'t>:G@
Q-?6o
m@y<wk(
/*Created on 2005-4-14*/ ;lQ>>[*
package org.flyware.util.page; !{?<(6;t
+,_%9v?3
import org.apache.commons.logging.Log;
K,o&gY
import org.apache.commons.logging.LogFactory; KTE X]
V6bjVd9|Z
/** #=T^XHjQ
* @author Joa #0f6X,3
* c
'rn8Jo}
*/ z[qi~&7:v
publicclass PageUtil { O|nLIfT
eUKl(
privatestaticfinal Log logger = LogFactory.getLog 3>6rO4,
FOAXm4"
(PageUtil.class); 4$y P_3
Yy{(XBJ~%t
/** b(Yxsy{U
* Use the origin page to create a new page S"/-)_{
* @param page Os/?iGlD*E
* @param totalRecords n}dLfg*
* @return R:`)*=rL%
*/ +xuj ]J
publicstatic Page createPage(Page page, int A!v:W6yiz
=u`tlN5pOT
totalRecords){ wg4Ol*y'
return createPage(page.getEveryPage(), G+t=+T2m
T|2v1Vj
page.getCurrentPage(), totalRecords); FEi@MJJ\e
} "vfpG7CG
P7epBWqDP
/** L1kAAR
* the basic page utils not including exception T7^?j :kJ/
C;%1XFzM
handler B2Kh~Xd
* @param everyPage %R<xe.X
* @param currentPage A`* l+M^z
* @param totalRecords 2%/+r
* @return page WIN3*z7oW
*/ as(Zb*PdH
publicstatic Page createPage(int everyPage, int ><qA+/4]_
+q%b'!&Q
currentPage, int totalRecords){ .;)V;!
everyPage = getEveryPage(everyPage); IN,=v+A
currentPage = getCurrentPage(currentPage); 9w6 uoM
int beginIndex = getBeginIndex(everyPage, k#-%u,t
3a'#Z4Z-
currentPage); <rFh93
int totalPage = getTotalPage(everyPage, =z4J[8bb
(v&iXD5t
totalRecords); (3 Z;c_N
boolean hasNextPage = hasNextPage(currentPage, !xU[BCbfYV
7b7WQ 7u
totalPage); !8Y A1 o
boolean hasPrePage = hasPrePage(currentPage); >=86*U~
_K B%g_{
returnnew Page(hasPrePage, hasNextPage, VNs3.
everyPage, totalPage, AzVv-!Y
currentPage, =imJ0V~RW
-56gg^Pnr
beginIndex); y@r0"cvz9
} _Nh`-R%B)
iqFC~].)
privatestaticint getEveryPage(int everyPage){ KV! (
return everyPage == 0 ? 10 : everyPage; Q\}Ck+d`a
} =y=MljEX
n7|,b-
<
privatestaticint getCurrentPage(int currentPage){ VI-6t"l
return currentPage == 0 ? 1 : currentPage; dl(!{tZ#
} vSY
YetL
1--Ka& H
privatestaticint getBeginIndex(int everyPage, int _}cD_$D
J06D_'{
currentPage){ yG;@S8zC
return(currentPage - 1) * everyPage; TiR00#b
} . I."q
OlgM7Vrl
privatestaticint getTotalPage(int everyPage, int m;0ZV%c*j
h@TP=
totalRecords){ :sttGXQX
int totalPage = 0; q0b*#j
DPkH:X
if(totalRecords % everyPage == 0) ,b:~Vpb1I
totalPage = totalRecords / everyPage; 211V'|a_>
else f`iDF+h<6
totalPage = totalRecords / everyPage + 1 ; !JBj%| !
u'^kpr`y
return totalPage; MY^o0N
} ;0`IFtz
S|fb'
privatestaticboolean hasPrePage(int currentPage){ biS{.
return currentPage == 1 ? false : true; HBZ6 Pj
} dkeMiLm
Ko)f:=Qo
privatestaticboolean hasNextPage(int currentPage, mW~*GD~r
s~ou$!|
int totalPage){ 6
$`l
return currentPage == totalPage || totalPage == .@ZrmO
o]]
5vLA)Al3
0 ? false : true; HA[7)T N1E
} < FY%QB)h
[,{Nu EI
";/ogFi
} )i_:[ l6
fe8hgTP|
FNw]DJ]
z|t2;j[
8m?cvI
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 X3~`~J
B4 5#-V
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Ug384RzHN
%m|1LI(
做法如下: QMy1!:Z&!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 [7 NO !^
QKhGEW~G
的信息,和一个结果集List: /,~g"y.;,
java代码: h
lSav?V_
Z:^ S-h
2H`>Kj
/*Created on 2005-6-13*/ 3d,:,f|h
package com.adt.bo; #hk5z;J5
)1YX+',"
import java.util.List; 2 .\"Q
Y/?z8g'p
import org.flyware.util.page.Page; LXZI|K[}k
3`)ej`
/** G&t|aY-
* @author Joa 7#SfuZ0@
*/ qz.l
publicclass Result { U$S{j&?
}0f~hL24
private Page page; KUpj.[5qo
3w"_Onwk
private List content; L$rr:^J
RS@[ +! :t
/** g)!q4
-q
* The default constructor 2dK:VC4U
*/ u \<APn
public Result(){ k3KT':*
super(); sXNb
} -8R SE4)
uvw1 _j?
/** oX'@,(6)
* The constructor using fields gI"cZ h3}
* 4j'`,a=
* @param page fwlicbs '
* @param content ( uG;Q
*/ (;H% r &
public Result(Page page, List content){ $My~sN8
this.page = page; t*dq*(3"c
this.content = content; a 7=lZZ?
} !6z{~Z:
B@#vS=g
/** N1.fV -
* @return Returns the content. -F 9xPw
*/ h0HK~S#xBv
publicList getContent(){ ~|N,{GaL
return content; `U|zNizO
} 0cVxP)J+
mIPDF1=)
/** {B e9$$W,
* @return Returns the page. RKM5FXX
*/ 3(nnN[?N,5
public Page getPage(){ JT=ax/%Mo
return page; =-&h@mB;G
} TtH!5{$s
#sk~L21A
/** l;&kX6 w
* @param content Do5.
* The content to set. e,Y<$kPV
*/ .}uri1k"@k
public void setContent(List content){ Y9&na&vY?
this.content = content; x34GRe!!
} B|8|f(tsSa
/ {[p?7x>
/** q~Al[`K
* @param page FMhuCl2
* The page to set. =+I-9=
*/ <M}O&?N
8x
publicvoid setPage(Page page){ g/\cN(X
this.page = page; !H<%X~|,
} q*C-DiV
} SLUQFoz}
BjA$^ i|8
SXN]${
@1<VvW=
0\s&;@xKk
2. 编写业务逻辑接口,并实现它(UserManager, ^,)nuUy
bI_MF/r''
UserManagerImpl) @; I9e
java代码: #!%zf{(C+
Oamz>Hplu
,V^$Meh
/*Created on 2005-7-15*/ ^".6~{
package com.adt.service; A zp!;+
ULgp]IS
import net.sf.hibernate.HibernateException; [hk/Rp7{
%Pj}
import org.flyware.util.page.Page; ~*UY[!+4^=
7,8TMd1`M
import com.adt.bo.Result; 8?x:PkK
pYu6[
/** /L5:/Z
* @author Joa q_mxZM
->
*/ jzZ]+'t
publicinterface UserManager { 8OO[Le]1
U0srwt97S
public Result listUser(Page page)throws &\Lu}t7Ru
ZLPj1L
HibernateException; c@)?V>oe
&%8IBT
} }$r]\v
N93R(x)%
xU6dRjYhH9
TeO'E<@
K5\l
(BB
java代码: UO!} 0'
e$JCak=
zr_L
V_e
/*Created on 2005-7-15*/ &A`,hF8
package com.adt.service.impl; Y(2Z<d
Jf\`?g3#
import java.util.List; (0.JoeA`y
R*XZPzg%
import net.sf.hibernate.HibernateException; yF%e)6
Q<ia
import org.flyware.util.page.Page; E*fa&G~s )
import org.flyware.util.page.PageUtil; pjFj{
@Y>PtA&w*
import com.adt.bo.Result; 0vBQzM Q
import com.adt.dao.UserDAO; H*P+>j&
import com.adt.exception.ObjectNotFoundException; Zk>m!F>,p
import com.adt.service.UserManager; a/3'!} &e
t~nW&]E
/** %+;l|Z{Uf
* @author Joa `D$^SHfyz
*/ z"QXPIXPk
publicclass UserManagerImpl implements UserManager { yLK %lP
&0 "*.:J9
private UserDAO userDAO; &^uaoB0
H{Lt,#
/** f5l\3oL
* @param userDAO The userDAO to set. [p}~M-$V8Y
*/ e"XolM0IM
publicvoid setUserDAO(UserDAO userDAO){ Wm5[+z|2?9
this.userDAO = userDAO; QnS#"hc\a
} *M0O&" ~j
`P-d. M6Oa
/* (non-Javadoc) W1t_P&i
* @see com.adt.service.UserManager#listUser F:[[@~z
]` A*7
(org.flyware.util.page.Page) VM\\.L
*/ 0Zo><=
public Result listUser(Page page)throws *yo'Nqu
-yg;,nCg
HibernateException, ObjectNotFoundException { yOvV"x]
int totalRecords = userDAO.getUserCount(); DIWyv-
if(totalRecords == 0) ,j\uvi(Y
throw new ObjectNotFoundException v0tFU!Q%
dLwP7#r
("userNotExist"); 8*&73cp
page = PageUtil.createPage(page, totalRecords); BI<9xl]a
List users = userDAO.getUserByPage(page); F$kiSjh9aJ
returnnew Result(page, users); 8}4.x3uw
} =MD)F
PxvxZJf$@
} e^\#DDm
`w8cV?
x!pd50-
)1R[X!KQ7
Tyb'p9
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 riaL[4c
f~TkU\Rh
询,接下来编写UserDAO的代码: 2Ur&_c6P
3. UserDAO 和 UserDAOImpl: Aw4)=-LKO
java代码: x_?K6[G&}
/6yVbo"
b&1hj[`)
/*Created on 2005-7-15*/
U2vb&Qu/
package com.adt.dao; fb^R3wd$ff
nA.U'=`
import java.util.List; 4e;
le&
_%B,^0;C
import org.flyware.util.page.Page; 3DB= Xh
)hoVB
import net.sf.hibernate.HibernateException; W_Y56@7e
$vYy19z
/** a>,_o(]cW
* @author Joa /Dt:4{aTOC
*/ ui|6ih$+
publicinterface UserDAO extends BaseDAO { T?=]&9Y'
d7zZ~n
publicList getUserByName(String name)throws uk,9N
C#1'kQO
HibernateException; F{.g05^y
6cbV[!BL
publicint getUserCount()throws HibernateException; NiE`u m
_D8 zKp
publicList getUserByPage(Page page)throws ;pfN
FYefn3b
HibernateException; .'2I9P\!
x;~@T9.
} @KLX,1K
ncOl}\Q9
l
6aD3?8LN
rwh4/h^S
>qO l1]uF
java代码: f><V;D#
v@s"*E/PF7
Z.unCf3Q
/*Created on 2005-7-15*/ Jcs
/i
package com.adt.dao.impl; vQn hb%
E piF$n
import java.util.List; 'xaEG,P
YZnFU( j
import org.flyware.util.page.Page; -y?ve od#
)-}<}< oO
import net.sf.hibernate.HibernateException; T%Zfo7
import net.sf.hibernate.Query; 6Rq +=X
e},:QL0X
import com.adt.dao.UserDAO; xt`a":lr u
HL>l.IG?
/** EUH9R8)
* @author Joa w Bm4~~_
*/ Fy$C._C$
public class UserDAOImpl extends BaseDAOHibernateImpl n: {f\
<4 /q5*&
implements UserDAO { Ag2Q!cq
H/8u?OC
/* (non-Javadoc) > #9
a&O
* @see com.adt.dao.UserDAO#getUserByName d& v 7l
J<Ki;_=I
(java.lang.String) YWV)C?5x&
*/ d0zp89BEn
publicList getUserByName(String name)throws UX|3LpFX&I
t0P_$+w.>
HibernateException { Y( K`3?A
String querySentence = "FROM user in class 55y{9.n*
- JFW ,8=8
com.adt.po.User WHERE user.name=:name"; q9InO]s&~=
Query query = getSession().createQuery BZXee>3"
t 0p
(querySentence); QAY:H@Gt:
query.setParameter("name", name); +G7[(Wz(z
return query.list(); 7suT26C
} j-FMWEp
JPgFTr
/* (non-Javadoc) #E<~WpP
* @see com.adt.dao.UserDAO#getUserCount() Cgf4E{\U!
*/ R /_vJHI
publicint getUserCount()throws HibernateException { $!z .[GL
int count = 0; Ze[\y(K!
String querySentence = "SELECT count(*) FROM Jk{v(W#
4wa3$Pk
user in class com.adt.po.User"; .6bo
Query query = getSession().createQuery 0 EA3>$;
v"Ryg]^_
(querySentence); \]\GDpu[
count = ((Integer)query.iterate().next la$%%@0/
Bw[IW[(~!
()).intValue(); c5i7mx:.
return count; #X'su`+
} UKB/>:R
+9<:z\B|
/* (non-Javadoc) X"HVK+
* @see com.adt.dao.UserDAO#getUserByPage />>KCmc
RcO.1@2
(org.flyware.util.page.Page) [?2?7>D8
*/ u'Hh||La"
publicList getUserByPage(Page page)throws X~\O]
n 4H'FZ
HibernateException { =~)rT8+)
String querySentence = "FROM user in class -G=.3
bux
x&EMg!
com.adt.po.User"; QNXS.!\P
Query query = getSession().createQuery b!"FM/%
!)}z{,Jx
(querySentence);
X]GodqL\
query.setFirstResult(page.getBeginIndex()) 6W;`}'ap
.setMaxResults(page.getEveryPage()); X2Q35.AB
return query.list(); qpa}6JVQ+j
} ;~`/rh
V\
aouYPxA`
} wg:\$_Og
v9t'CMU
sULsU t#
Q(BZg{
6IJ;od.\b$
至此,一个完整的分页程序完成。前台的只需要调用 r.=.,R
cnG>EG
userManager.listUser(page)即可得到一个Page对象和结果集对象 Sm|TDH
Upg8t'%{op
的综合体,而传入的参数page对象则可以由前台传入,如果用 nmuU*oL
AOTtAV_e
webwork,甚至可以直接在配置文件中指定。 y4&x`|tv
m-cw5lW
下面给出一个webwork调用示例: moMNd(p
java代码: jpMMnEVj6P
7+6I~&x!Lz
7WmY:g#s
/*Created on 2005-6-17*/ <