Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 x&d<IU)5
l?;S>s*\?
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 nDvWOt
u[DV{o
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 n9^zAcUbAW
o%a$m9I
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 K0]Wb=v
M*N8p]3Cq
。 )UJMmw\
D[mYrWHpn
分页支持类: mqL+W
<#-ERQw
java代码: )j]RFt
g2I @j3
:>k\uW
package com.javaeye.common.util; Sy_M!`B
7vFqO;
import java.util.List; sMx\WTyz
"`k[4C
publicclass PaginationSupport { YS*t7
]nh)FMo
publicfinalstaticint PAGESIZE = 30; uRIr,U^
f8lww)^,v
privateint pageSize = PAGESIZE; e+mD$(h
809-p_)B
privateList items; K5$ y
!FO)||'[
privateint totalCount; P_gQ-pF.
!ktr|9Bl
privateint[] indexes = newint[0]; ~>n<b1}W
3]i1M%'i
privateint startIndex = 0; C6`8dn
RUEUn
public PaginationSupport(List items, int kL-+V)Kl
-Da_#_F
totalCount){ Sv ,_G'
setPageSize(PAGESIZE); e#wn;wo?
setTotalCount(totalCount); $f+9svq
setItems(items); bpzA '
g>
setStartIndex(0); x^"OH
} @;0Ep0[
-3fvO~
public PaginationSupport(List items, int = 4If7
[ ,dsVd
totalCount, int startIndex){ :MVD83?4
setPageSize(PAGESIZE); >Ry4Cc
setTotalCount(totalCount); OQq7|dZu
setItems(items); F2&KTK
setStartIndex(startIndex); eXYR/j<8
} L`\ILJz
6T-(GHzfHJ
public PaginationSupport(List items, int iAN#TCwLT7
~4M]SX1z
totalCount, int pageSize, int startIndex){ ,oCr6 ]
setPageSize(pageSize); i<
ih :
setTotalCount(totalCount); (.c?)_G,
setItems(items); 6Z$T&Ul{
setStartIndex(startIndex); W+S>/`N
} k`- L5#`
w*+rB p,f
publicList getItems(){ >g?,BK@
return items; u1uY*p
} K"pfp !Y
1#'wR3[+
publicvoid setItems(List items){ Xf0pQ]8\
this.items = items; 4&\m!s
} @*oi1_q
TzOf&cs/r
publicint getPageSize(){ tFGLqR%/
return pageSize; _]\mh,}
} ?$
3=m)s
b7$?'neH/.
publicvoid setPageSize(int pageSize){ CB~&!MdMr
this.pageSize = pageSize; Bpgl
U=Qr
} h41v}5!-
hi37p1t
publicint getTotalCount(){ cIgF]My*D@
return totalCount; 1G\ugLm
} yY1&hop
sB6UlX;b:
publicvoid setTotalCount(int totalCount){ .(sT?M`\J
if(totalCount > 0){ (i`DUF'#y
this.totalCount = totalCount; Eb.{M
int count = totalCount / MG~^>
I{E10;
pageSize; )b
=$!
if(totalCount % pageSize > 0) W?$
ImW
count++; f.,-KIiF
indexes = newint[count]; 9+L!
A
for(int i = 0; i < count; i++){ Q/< $ (Y
indexes = pageSize * )P$
IXA\
3}H94H)]a
i; !u^(<.xJ
} k8h$#@^
}else{ ? 0%lB=qQ
this.totalCount = 0; O6`@'N>6P
} *P_TG"^{W
} -X |G
<'/+E4m
publicint[] getIndexes(){ f[.]JC+,
return indexes; UZ<!(g.
} _uRgKoiy
c<e$6:|xM
publicvoid setIndexes(int[] indexes){ y"7?]#$9/
this.indexes = indexes; 6rRPqO
j
} jtZ@`io
?vZ&CB
publicint getStartIndex(){ oV*3Mec
return startIndex; X}^,g
} @]A4{
Tj.;\a|d
publicvoid setStartIndex(int startIndex){ BqR8%F
if(totalCount <= 0) a/?gp>M9
this.startIndex = 0; <uA|nYpp
elseif(startIndex >= totalCount) Z!#zr@'k
this.startIndex = indexes Q
i?
7Npz
{C{I
[indexes.length - 1]; 39u!j|VH
elseif(startIndex < 0) u tQ_!3u
this.startIndex = 0; gP<l
else{ QtRKmry{
this.startIndex = indexes TIS}'c'C
w{0UA6 +
[startIndex / pageSize]; =6? 3c\
} H*l8,*M}
} /9[nogP
|,.glL
publicint getNextIndex(){ {4#'`Eejj
int nextIndex = getStartIndex() + T9u/|OP
`/#6k>
pageSize; E9|i:
if(nextIndex >= totalCount) h8n J$jg
return getStartIndex(); Yh4e\]ql~N
else L!5%;!>.P
return nextIndex; vK|dP3
} *F&C`]
O10h(Wg
publicint getPreviousIndex(){ #.) qQ8*(
int previousIndex = getStartIndex() - iA=9Lel
Nn%{Ka
pageSize; Jln dypE
if(previousIndex < 0) +`\C_i-
return0; 8on2BC2
else p7|~x@q+
return previousIndex; :U?Kwv8 s
} OrHnz981K
lB,.TK
} M@
mCBcbN
KO:o GUR
h4ZrD:D0\
BjJ+~R
抽象业务类 cp[k[7XGD
java代码: _t3n<
I,.>tC
w${=]h*2
/** Cvq2UNz(R
* Created on 2005-7-12 "M2HiV
*/ AOeptv^k3}
package com.javaeye.common.business; 9QZ;F4 r
J}lBKP:-*
import java.io.Serializable; )x#^fN~ 7`
import java.util.List; ^cd+W?
4K:p
import org.hibernate.Criteria; d&t|Y:,8
import org.hibernate.HibernateException; }F**!%4d
import org.hibernate.Session; _aq3G9C_
import org.hibernate.criterion.DetachedCriteria; _v<EFal
import org.hibernate.criterion.Projections; +K]kGF
import -cEjB%Neo
)mJl-u[0+
org.springframework.orm.hibernate3.HibernateCallback;
4mUQVzV
import YG<?|AS/
}7k+tJ<
org.springframework.orm.hibernate3.support.HibernateDaoS Fn$EP:>
+.5 /4?
upport; |no '^
G[)QGZ}8b
import com.javaeye.common.util.PaginationSupport; HLa|ycB%
,M5J~Ga
public abstract class AbstractManager extends T+RfMEdr
;L++H5Kz6
HibernateDaoSupport { Kp8!^os
;E(%s=i
privateboolean cacheQueries = false; <SbW
QbN
h9RG?r1
privateString queryCacheRegion; vfm|?\
pzH N:9r
publicvoid setCacheQueries(boolean a";(C,:0
ma vc$!y
cacheQueries){ 4Rp2
this.cacheQueries = cacheQueries; [{-
Oy#T<
} }n oI2.-#
UC3?XoT\
publicvoid setQueryCacheRegion(String x-mRPH
u-yQP@^H
queryCacheRegion){ %jim] ]<S[
this.queryCacheRegion = #GY;.,
-#|J
queryCacheRegion; _6(QbY'JV`
} v|"Nx42
rx
CSs
publicvoid save(finalObject entity){ ) j_g*<
getHibernateTemplate().save(entity); NAlYfbp
} +t})tDPXw
a3sXl+$D@
publicvoid persist(finalObject entity){ a>G|t5w
getHibernateTemplate().save(entity); 6m|j "m
} Ft#d&
I
$-EbJ
publicvoid update(finalObject entity){ _T7tq
getHibernateTemplate().update(entity); wZ5+ H%x
} |#Z:v1]"
Ir }r98lz
publicvoid delete(finalObject entity){ ,?P @ :S<8
getHibernateTemplate().delete(entity); %70sS].@
} )E'iC
_p<s!
publicObject load(finalClass entity, ;3-5U&Axt
Re0ma%~LP
finalSerializable id){ *am.NH\
return getHibernateTemplate().load F$N"&<[c
Wf +j/RxTi
(entity, id); bO^#RVH
} ]4ya$%A
.'saUcVg:
publicObject get(finalClass entity, pZ}4'GnZI
RU|{'zC\v
finalSerializable id){ i"p)%q~ z
return getHibernateTemplate().get TLU^ad#9E
_p"nR
(entity, id); DP6 M4
} 8A~5@
b7^VWX%
publicList findAll(finalClass entity){ _pnJ/YE
return getHibernateTemplate().find("from 3.Oc8(N^}
g@BQ!}_#5
" + entity.getName()); ~q 0)+'
} =X'i^Q
JBo/<W#|
publicList findByNamedQuery(finalString rhGHR5
g
|[7xTD
namedQuery){ ,b%T[s7
return getHibernateTemplate llXyM */
T\55uQ
().findByNamedQuery(namedQuery); bwR24>8lP
} hz\Fq1
C:
@T5m
publicList findByNamedQuery(finalString query, WLma)L`L
9
,=7Uh#7
finalObject parameter){ Iww.Nd2
return getHibernateTemplate (p08jR
'5
AL74q[>
().findByNamedQuery(query, parameter); .H
{
} FIG3P))
Sp3?I2 o
publicList findByNamedQuery(finalString query, Av:5v3%
{{7%z4l
finalObject[] parameters){ %]S~PKx
return getHibernateTemplate 0!!b(X(
(vMC.y5
().findByNamedQuery(query, parameters); wg\*FfQn
} yJkERiJV
8.3888
publicList find(finalString query){ B#9rqC
return getHibernateTemplate().find Z[[o u?c
cLj@+?/
(query); (\}>+qS[
} ^|M\vO
.>NhC"
publicList find(finalString query, finalObject Yj99[
c#]
z;yb;),
parameter){ !r]elX
return getHibernateTemplate().find (=cR;\s<
xs_l+/cZ
(query, parameter); :SjTkfU
} UE33e(Q<
KLK
'_)|CT
public PaginationSupport findPageByCriteria #-?pY"N,
,y@`wq>O
(final DetachedCriteria detachedCriteria){ >Ng7q?h
return findPageByCriteria ^_BHgbS%;
JfS:K'
(detachedCriteria, PaginationSupport.PAGESIZE, 0); )y&}c7xW
} &"]Uh
d5mhk[p7\J
public PaginationSupport findPageByCriteria *F|j%]k~
*NzHY;e
(final DetachedCriteria detachedCriteria, finalint Z".mEF-b
!mLQdkTE
startIndex){ o7Ms]AblT
return findPageByCriteria [zmx
}GX[N\$N
(detachedCriteria, PaginationSupport.PAGESIZE, SA@MJ>Z
\lwYDPY:
startIndex); x-O9|%aRJ
} :a3 +f5
T7`9[
public PaginationSupport findPageByCriteria ov>Rvy
wN1%;~?7
(final DetachedCriteria detachedCriteria, finalint `vs=
CYs
Blv!%es
pageSize, Z
|wM
finalint startIndex){ SJ$N]<d
return(PaginationSupport) Mr'P0^^
/Ud<4j-
getHibernateTemplate().execute(new HibernateCallback(){ LnZzY0
publicObject doInHibernate qd\5S*Z1
HPJ\]HV(
(Session session)throws HibernateException { )vVt{g
Criteria criteria = Ln/6]CMl
l`D^)~o8
detachedCriteria.getExecutableCriteria(session); ."9t<<!
int totalCount = s6Ox!)&
<j" }EEb^
((Integer) criteria.setProjection(Projections.rowCount .R5[bXxe7
z*?-*6W
()).uniqueResult()).intValue(); $OOZ-+8
criteria.setProjection vpR^G`/
$t.i)wg +
(null); ^3B)i=
List items = &<8Q/m]5
H{Tt>k
criteria.setFirstResult(startIndex).setMaxResults |Y#KMi ~
:.KN;+tP
(pageSize).list(); MJJ]8:%
PaginationSupport ps = GQ<]Sd}[
?Ne@OMc
new PaginationSupport(items, totalCount, pageSize, =\CJsS.
9+<%74|,
startIndex); $B6CLWB
return ps; @pq#?
} *xm(K+j
}, true); O%RkU?ME
} jSa9UD
Uawf,57v<
public List findAllByCriteria(final 3k)W0]:|<
zO#{qF+~;
DetachedCriteria detachedCriteria){ v^;-w~?3
return(List) getHibernateTemplate a#H2H`%
UUb n7&
().execute(new HibernateCallback(){ [KrWL;[1<
publicObject doInHibernate #sl_
BC9
8vFt<k}G
(Session session)throws HibernateException { O:02LHE
Criteria criteria = =@%;6`AVcp
B&^WRM;7t
detachedCriteria.getExecutableCriteria(session); ke.{wh\0
return criteria.list(); VrL==aTYXs
} .XPcH(q
}, true); e.pm`%5bO
} 1 o<l;:
!:
e(-
public int getCountByCriteria(final c)H(w
4dy2m!
DetachedCriteria detachedCriteria){ a^yBtb~,P
Integer count = (Integer) lZT9 SDtS
h{zE;!+)D
getHibernateTemplate().execute(new HibernateCallback(){ @\-i3EhR
publicObject doInHibernate J6x#c`Y
yn&AMq
]o
(Session session)throws HibernateException { Z4YQ5O5
Criteria criteria = |,zcrOo]
hw[ jVx
detachedCriteria.getExecutableCriteria(session); +$]eA'Bh@
return TBq;#+1W
|n9~2R
criteria.setProjection(Projections.rowCount I5RV:e5b
9o-fI@9
()).uniqueResult(); !N5+.E0j
} R Wa4O#
}, true); ^/;W;C{4
return count.intValue(); HI}$Z=C
} BR8W8nRb
} $HjKELoJ<
?Y6MC:l<
|~'D8 g:Ak
J?/.|Y]e
O6rrv,+_L
>dH5n$Gb
用户在web层构造查询条件detachedCriteria,和可选的 <^:e)W
g=eYl_P6
startIndex,调用业务bean的相应findByCriteria方法,返回一个 L #'N
`c
3IS5
PaginationSupport的实例ps。 8o' a
EJqzh
i5
ps.getItems()得到已分页好的结果集 r()%s3$q
ps.getIndexes()得到分页索引的数组 |||uTfrJ
ps.getTotalCount()得到总结果数 uQy5t:!
ps.getStartIndex()当前分页索引 %9.]
bd|%F
ps.getNextIndex()下一页索引 KX*Hev'K
ps.getPreviousIndex()上一页索引 $`q8-+{
\Y'#}J"dh
e|wH5(V
ZLA&<]Ad"$
6;/>asf
ciKkazx.
\Ol3kx|
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]7WBoC8
?3:OPP`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 e@k`C{{C]o
/m,0H)w1
一下代码重构了。 _!FM^N}|
TmS;ybsG
我把原本我的做法也提供出来供大家讨论吧: aQax85
7 mulNq
首先,为了实现分页查询,我封装了一个Page类: qwAN=3@
java代码: wn*z*
x?Wt\<|h!
UN`F|~@v
/*Created on 2005-4-14*/ COS(pfC
package org.flyware.util.page; mT
N6-V
g*UI~rp
/** $@_7HE3
* @author Joa 4}{S8fGk%
* MFHPh8P
*/ UA4Q9<>~
publicclass Page { @Z$`c{V<
@_0g "Ul
/** imply if the page has previous page */ lD09(|`
privateboolean hasPrePage; D
.3Q0a6
C]aa^_Ldd-
/** imply if the page has next page */ 2A3;#v
privateboolean hasNextPage; \Cx)
~bq<
<YbOO{
/** the number of every page */ l ' ]d&
privateint everyPage; 9kPwUAw
oF/5mh__(K
/** the total page number */ 9%\<x
privateint totalPage; ]d"4G7mu`l
RL>Nl ow
/** the number of current page */ 5GK=R aV
privateint currentPage; }Gpw2
,x5`5mT3
/** the begin index of the records by the current sr\l z}JW
STgl{#
query */ Kb0OauW
privateint beginIndex; 6y)xMX
%hU8ycI*h
7BCCQsz<
/** The default constructor */ /'1UfjW>
public Page(){ TX{DZ#
}~lF Rf
} OVO0Emv
[KkLpZG
/** construct the page by everyPage jIMaPT
* @param everyPage {! RW*B
* */ s-r$%9o5
public Page(int everyPage){ Ah)OyO6
this.everyPage = everyPage; *iF>}yh e
} W|=?-
7Z>u|L($m
/** The whole constructor */ GCrh4rxgg
public Page(boolean hasPrePage, boolean hasNextPage, |0(Z)s,
L>{E8qv>w
[!{*)4$6
int everyPage, int totalPage, 64}Oa+*s
int currentPage, int beginIndex){ M;W{A)0i1
this.hasPrePage = hasPrePage; 9\*xK%T+
this.hasNextPage = hasNextPage; CogLo&.
this.everyPage = everyPage; =mCUuY#
this.totalPage = totalPage; j' -akXo<
this.currentPage = currentPage; y]=v+Q*+
this.beginIndex = beginIndex; ~az6n)
} (c(c MC'
?PWD[mQE\
/** Ze~ a+%Sb
* @return 9QJ=?bIC#
* Returns the beginIndex. >q
<,FY!A
*/ NTiJEzW}
publicint getBeginIndex(){ `Oys&]vb
return beginIndex; 1W-t})!a
} cWgiFv
9A\J*OU
/** VS^%PM#:/
* @param beginIndex ,*0>CBJvv
* The beginIndex to set. xk86?2b{)
*/ )8&Q.? T
publicvoid setBeginIndex(int beginIndex){ EA75
D&>I
this.beginIndex = beginIndex; _6qf>=qQ`"
} BW:&AP@B
5L|yF"TI#
/** AEK * w4
* @return [8Ub#<]]
* Returns the currentPage. uf`o\wqU
*/ ~/[cZY@
publicint getCurrentPage(){ po"M$4`9
return currentPage; >0+m
} 133lIX+(k
{i^ ?XdM
/** yVQqz
* @param currentPage `a:@[0r0U
* The currentPage to set. Y,WcHE
*/ x{ ~-YzWho
publicvoid setCurrentPage(int currentPage){ >;o^qi_$
this.currentPage = currentPage; *P:`{ZV7=W
} [x!T<jJ
,{itnKJC
/** DcoTa-~
* @return 3Q[]lFJ}F
* Returns the everyPage. M O* m@
*/ (Tn*;Xjq
publicint getEveryPage(){ :<ujk
return everyPage; 4_PMl6qo
} abD55YJY
wias]u|
/** VjYfnvE
* @param everyPage &Z=}H0y
q
* The everyPage to set. w[PW-m^`
*/ h'UWf"d
publicvoid setEveryPage(int everyPage){ E( 8!VY ^
this.everyPage = everyPage; FO3!tJ\L
} .IpwTke'
C_O7
/** Ca+d
?IS
* @return ,Q(n(m'
* Returns the hasNextPage. bLu6|YB
*/ JS&l
h
publicboolean getHasNextPage(){ .XLe\y
return hasNextPage; G7%Nwe~Y
} 0g]ABzTn
lDp5aT;DsM
/** ?xK9
* @param hasNextPage @Z@yI2#e
* The hasNextPage to set. 5[I> l
*/ jSVb5P
publicvoid setHasNextPage(boolean hasNextPage){ .d8) *
this.hasNextPage = hasNextPage; g IX"W;
} sdS<-!
%u4
,PRM(n -
/** Ow//#:
* @return X@x:
F|/P
* Returns the hasPrePage. pl fz)x3
*/ X~GZI*P
publicboolean getHasPrePage(){ &xH>U*c
return hasPrePage; f=~@e#U
} i-sE\m
j(nPWEyJM
/** ]}>GUXe)^
* @param hasPrePage <%pi*:E|
* The hasPrePage to set. jE2ziK
*/ J[LGa:``
publicvoid setHasPrePage(boolean hasPrePage){ axU!o /m>
this.hasPrePage = hasPrePage; aeSy,:
} J>hl&J
seAkOIc
/** (jY.S|%
* @return Returns the totalPage. + 6r@HK`,t
* (O&~*7D*
*/ XFK$p^qu
publicint getTotalPage(){ \iowAo$
return totalPage; woR((K] #G
} .s7/bF
,vg8iRa
/** 3w{i5gGn
* @param totalPage .fo.mC@a
* The totalPage to set. YqNhD6
*/ /8W}o/,s5
publicvoid setTotalPage(int totalPage){ dP)8T
this.totalPage = totalPage; pVbX#3
} h3@mN\=h'
%*}JDx#@
} T^A:pL1
/"iYEr%_
)E6m}? H5
MlRgdVX
Mqw&%dz'_
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 \8Blq5n-O*
9=3V}]^M
个PageUtil,负责对Page对象进行构造: "]MF =-v
java代码: ;=h^"et
HLk}E*.mC
NTAPx=!1*
/*Created on 2005-4-14*/ _Seiwk&
package org.flyware.util.page; P7u5Ykc*
<PV @JJ"
import org.apache.commons.logging.Log; 3%<ia$
import org.apache.commons.logging.LogFactory; BvX!n"QIb
+hXph
/** zT_{M
qY
* @author Joa -pqShDar|
* 'Iu$4xo`[
*/ xO?~@5
publicclass PageUtil { cE]tvL:g
#exE~@fy-
privatestaticfinal Log logger = LogFactory.getLog {_(;&\5
MIt\[EB
(PageUtil.class); ,dh*GJ{5
00b
)B g
/** :O//A6v
* Use the origin page to create a new page s/,St!A4!
* @param page /}M@
@W
* @param totalRecords f0wQn09
* @return uE5kL{Fv
*/ rxa8X wo8
publicstatic Page createPage(Page page, int _HGDqjL
MHxv@1)K|Y
totalRecords){ )QI]b4[
return createPage(page.getEveryPage(), ~=0zZTG
^lf;Lc
page.getCurrentPage(), totalRecords); N{Is2Ia
} 5,?9#n\E,
kv(N/G
/** ;AG5WPI
* the basic page utils not including exception CH9#<?l
7qzI]
handler [IV8
* @param everyPage Ns1u0$fg
* @param currentPage \f{C2d/6j
* @param totalRecords W*U\79H
* @return page AeUwih.
4
*/ `?Y/:4
publicstatic Page createPage(int everyPage, int O 6A:0yM4
2!" N9Adt
currentPage, int totalRecords){ >mt<`s
everyPage = getEveryPage(everyPage); eU{=x$o6S
currentPage = getCurrentPage(currentPage); MWhFNfS8=
int beginIndex = getBeginIndex(everyPage, IL>Gi`Y&
{SROg;vA
currentPage); vn,L),"=
int totalPage = getTotalPage(everyPage, +Do7rl
ze#LX4b I
totalRecords); <[a9"G7
boolean hasNextPage = hasNextPage(currentPage, &p4q# p7,
z),l&7
totalPage); ]
YQ*mvI]
boolean hasPrePage = hasPrePage(currentPage); :_H$*Q=1
Wb*d`hzQ}
returnnew Page(hasPrePage, hasNextPage, pQEHWq"Q
everyPage, totalPage, rcQ?E=V2O
currentPage, @+xkd(RfN
WVwNjQ2PM
beginIndex); 0c:CA>F
} -?e~S\JH
J@yy2AZnO
privatestaticint getEveryPage(int everyPage){ Q) FL|
return everyPage == 0 ? 10 : everyPage; g7d) YUc
} $> #PhOC
^QFjBQ-Hai
privatestaticint getCurrentPage(int currentPage){ t3bDi/m
return currentPage == 0 ? 1 : currentPage; YQYN.\
} BHFWig*{
7i/?+|
privatestaticint getBeginIndex(int everyPage, int V?5_J%
//6m2a
currentPage){ y4envjl0
return(currentPage - 1) * everyPage; r}vI#;&
} .g4bV5ma3
f#^%\K:YYR
privatestaticint getTotalPage(int everyPage, int M{z+=c&w
*M KVm)Iv
totalRecords){ YR[Ii?
int totalPage = 0; ,L_p"A
q+LjWZ+O
if(totalRecords % everyPage == 0) P7@qvg
totalPage = totalRecords / everyPage; E[_Z%zd^
else <pPI:D@G
totalPage = totalRecords / everyPage + 1 ; P^1rNB
Vwv O@G7A
return totalPage; :.sK:W("v
} 1S_KX.
lYy0
privatestaticboolean hasPrePage(int currentPage){ ]bS\*q0Zf(
return currentPage == 1 ? false : true; nC`=quM9
} }25{"R}K
%oN^1a'&)
privatestaticboolean hasNextPage(int currentPage, {OQ sGyR?
kv5D=0r
int totalPage){ $RF"m"
return currentPage == totalPage || totalPage == LY^BkH'
,
:kCt=4%
0 ? false : true; "w_(p|c m=
} TJO|{Lxm
u`
v8wN2[fC
} d5WE^H)E.
I#9K/[
=#>P!
qLPI^g,
} 10Dvt>+
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。 ,cbP yg
2poU\|H
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 + ^~n09
iAXx`>}m
做法如下: DpTQP u9
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 3HfT9
-98bX]8
的信息,和一个结果集List: Y3-15:-
java代码: a_Xh(d$
12k)Ek9
-pLb%f0?
/*Created on 2005-6-13*/ 9K%E+_7b
package com.adt.bo; 4V[+6EV
sb8SG_ c.
import java.util.List; Z i|'lHr
H)(Jjk-O
import org.flyware.util.page.Page; %Cm4a49FNi
L-=^GNh
/** LTJ|EXYA
* @author Joa l?#([(WM
*/ _s=[z$EN&
publicclass Result { iF`E>%#
'RG`DzuF
private Page page; 3 #jPQ[+
"h)+fAT|,
private List content; tb_}w@:kU
6%:'2;xM
/** %=NqxF>>
* The default constructor u/hD9g~H7K
*/ AoTL)',
public Result(){ O-: ~6A
super(); /S|Pq!4<
} W]reQ&<Z
eBBh/=Zc
/** 7]
~'8
* The constructor using fields B%r)~?6DM
* R':a,6O
* @param page )~!Gs/w6
* @param content 2"%d!"
*/ H,zRmK6A%
public Result(Page page, List content){ Bv/v4(G5g
this.page = page; znu?x|mV
this.content = content; mEE/Olh W
} jIuE1ve
k deJB-
/** "$m3xO
* @return Returns the content. {L.0jAwB
*/ HW{+THNj
publicList getContent(){ mT\]
return content; =(@J+Ou
} GKm)wOb(*S
*a\1*Jk
/** rsiG]o=8
* @return Returns the page. V_Y SYG9f
*/ !QC->
public Page getPage(){ N !H iQ
return page; 'm-s8]-W
} Vwl`A3Y
LoNz
1KJL
/** w'U;b
* @param content O^`Y>>a
* The content to set. $L;7SY?
*/ 5w{_WR6,
public void setContent(List content){ Jd)|==yD
this.content = content; Z=wLNm H
} 6B|IbQ^
t0hg!_$bq
/** "y5c)l(Rg
* @param page MbjH\XRB
* The page to set. x+^iEj`gk
*/ /S P^fB*y
publicvoid setPage(Page page){ B;_M52-B
this.page = page; .K:>`~<)
} G$`/86A )
} C;STJrew
`)K1[&
LVO`+:
-w^E~J0*L
wYNh0QlBH
2. 编写业务逻辑接口,并实现它(UserManager, Rz%+E0
'N'EC`R
UserManagerImpl) Z?1.Y7Npr
java代码: -YRF^72+
8]+hfB/
8+
Hho@=
/*Created on 2005-7-15*/ U%U%a,rA5s
package com.adt.service; dp-8,Seu
DTgF,c
import net.sf.hibernate.HibernateException; +=;F vb
>_tn7Z0L
import org.flyware.util.page.Page; B
ljZ&wZW
dt;R
import com.adt.bo.Result; H?^Poe(=(
,9
/** }J"}poB:
* @author Joa NcFHvK
*/ ]6FpUF#<D
publicinterface UserManager { bIwt#:v
P(qUx9
public Result listUser(Page page)throws JAc-5e4
9?@M Zh
HibernateException; -:>Mi5/ s
*7DQ#bD
} 0FHN
.gx*gX1<
1;g>?18@
BWz*!(
-bcm"(<T'
java代码: >*k3D&
yv]/A<gP+
@
L?7`VoE
/*Created on 2005-7-15*/ 7$}lkL
package com.adt.service.impl; EXoT$Wt{$
53@*GXzE
import java.util.List; |*jnJWH4:
~b\bpu
import net.sf.hibernate.HibernateException; ,Q2` N{f
.k Gg}
import org.flyware.util.page.Page; #!C/~"Y*`|
import org.flyware.util.page.PageUtil; M|7xI
FL"7u2rh,
import com.adt.bo.Result; "J3@Z,qW
import com.adt.dao.UserDAO; ;NBJ@E,
import com.adt.exception.ObjectNotFoundException; jQ(qaX&
import com.adt.service.UserManager; 2["bS++?
r1JKTuuo
/** ?neXs-'-p
* @author Joa *)H?d
*/ x>Q\j>^
publicclass UserManagerImpl implements UserManager { -05#/-Z=
dI{)^
private UserDAO userDAO; 9;sebqC?
@aWvN;v
/** W=%}~7*
* @param userDAO The userDAO to set. d1vC-n
N
*/ {!Jw+LPv$$
publicvoid setUserDAO(UserDAO userDAO){ ,o*x\jrGw
this.userDAO = userDAO; Z2j
M.[hq
} [*]&U6\j
?%{v1(
/* (non-Javadoc) j[
kg9z
* @see com.adt.service.UserManager#listUser pa4zSl
Rs8^ 27
(org.flyware.util.page.Page) Yfs60f
*/ t1wNOoRa
public Result listUser(Page page)throws %N=-i]+Id
oj;Rh!O
HibernateException, ObjectNotFoundException { QI.{M$,m~
int totalRecords = userDAO.getUserCount(); m\O<Yc keA
if(totalRecords == 0) 6;"jq92in*
throw new ObjectNotFoundException R>BnUIu
-5\hZ!!J2
("userNotExist"); ^fQ ]>/u
page = PageUtil.createPage(page, totalRecords); q`{crY30
List users = userDAO.getUserByPage(page); oGu-:X=`9
returnnew Result(page, users); iQ~;to;Y
} D/5 ah_;
.|G([O^H
} vB
hpD
~$Xz~#~
XcAx@CY9c
\U\ W Q
iLIH |P%
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 i<m 1^a#C'
ZQlja
询,接下来编写UserDAO的代码: ,Tvfn`;(
3. UserDAO 和 UserDAOImpl: Mxc0=I'a
java代码: [z'PdYQR/{
wi|'pKG
]N!8U_U3
/*Created on 2005-7-15*/ G0Eqo$W)S
package com.adt.dao; W]}y:_t4
9nu!|reS
import java.util.List; &Egw94l
\_bk+}WJ]s
import org.flyware.util.page.Page; ( d#E16y
PJ5~,4H-4
import net.sf.hibernate.HibernateException; vR[XbsNM
U(4>e!
/** [AstD9
* @author Joa =aX;-
*/ Bvk 8b
publicinterface UserDAO extends BaseDAO { s{#rCc)
P+tRxpz
publicList getUserByName(String name)throws Oi+9kk
e
e`27 ?
HibernateException; qb'4x){
Ka%u#};
publicint getUserCount()throws HibernateException; gY9HEfB
&FH