Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %1:c hvS
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >adV(V<
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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 HT`1E0G8)
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 0&fl#]oCE
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。 ^O%9yEo
J^3H7 ]
分页支持类: `EMi0hm&H
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java代码: ]re'LC!d
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package com.javaeye.common.util; q^bO*bv
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import java.util.List; H}b\`N[nr
&/ouW'oP
publicclass PaginationSupport { h{]#ag5`
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publicfinalstaticint PAGESIZE = 30; %%g-GyP
1
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privateint pageSize = PAGESIZE; LD55n%|0`H
[!?wyv3
privateList items; 68x}w
Ae
d5U; $q{o
privateint totalCount; 4#Eul
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privateint[] indexes = newint[0]; J_ V,XO
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privateint startIndex = 0; -i_En^Fi
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public PaginationSupport(List items, int Gc;B[/:
1!/-)1t
totalCount){ T"W9YpZ
setPageSize(PAGESIZE); fI11dE9&?[
setTotalCount(totalCount); jzrt7p*k}
setItems(items); 6q%ed
UED
setStartIndex(0); "T*I|
} 97x%w]kV
sx-F8:Qa
public PaginationSupport(List items, int BW71 s
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totalCount, int startIndex){ k!13=Gh
setPageSize(PAGESIZE); v*L
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setTotalCount(totalCount); $-w5o`e
setItems(items); #`j][F@N
setStartIndex(startIndex); ^/{4'\p
} L<)Z> @fR
Mdky^;qq3;
public PaginationSupport(List items, int CZfE
|T~
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totalCount, int pageSize, int startIndex){ IHVMHOq}'
setPageSize(pageSize); ]BfR.,,
setTotalCount(totalCount); .93S>U< _
setItems(items); 6!RikEAh
setStartIndex(startIndex); irmwc'n]
} 9}XT'+`y
ZvyjMLf
publicList getItems(){ ni0LQuBp
return items; xSOoIsL[
} ;/aB)JZ5=
>D3zV.R
publicvoid setItems(List items){ !5E9sk{)
this.items = items; CKN8z
} Zx9.p Fc"
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publicint getPageSize(){ @e={Wy+Vm(
return pageSize; b.,$# D{p
} xBt<Yt"
W60Q3
publicvoid setPageSize(int pageSize){ H-m`Dh5{
this.pageSize = pageSize; F_ _H(}d
} s79q5
B%y! aQep
publicint getTotalCount(){ 4UazD_`'
return totalCount; `:R-[>5P8
} ^^'[%ok
tNYJQ
publicvoid setTotalCount(int totalCount){ &R0OeRToUb
if(totalCount > 0){ ,?fN#gc :
this.totalCount = totalCount; j]#wrm
int count = totalCount / T[m ~6
=;g= GcVK
pageSize; <gR`)YF7
if(totalCount % pageSize > 0) Gk{W:866
count++; |O%:P}6c
indexes = newint[count]; ujow?$&
for(int i = 0; i < count; i++){ v'K
% %z
indexes = pageSize * wd"TM
M,ppCHy/$
i; }]tFz}E\
} $e>/?Ss
}else{ { _-wG3f|
this.totalCount = 0; 'G52<sF
} S ]vW&r3`
} KxGKA
8g-P_[>
publicint[] getIndexes(){ w<v1N
return indexes; l&vm[3
} $+0=GN
`!] R!T@C
publicvoid setIndexes(int[] indexes){ `:V}1ioX5
this.indexes = indexes; Q %+}
} e21E_exM0
,I/2.Q})[
publicint getStartIndex(){ &zO3qt6
return startIndex; oo;;y,`8py
} 2%`^(\y
mu 2
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) pCz@(:0
this.startIndex = 0; #4Dn@Gqh.Y
elseif(startIndex >= totalCount) vYYS.ve
this.startIndex = indexes FLVbkW-G.
pk;ff q@
[indexes.length - 1]; '2wXV;`
elseif(startIndex < 0) YCir Oge
this.startIndex = 0; hN Z4v/
else{ A*G
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this.startIndex = indexes 8f /T!5
JmnBq<&,0
[startIndex / pageSize]; A4~D#V
} YtV |e|aD
} sI^@A=.@
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publicint getNextIndex(){ Pd)K^;em
int nextIndex = getStartIndex() + <$RS*n
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pageSize; )j{WeG7L
if(nextIndex >= totalCount) HXD*zv@ *6
return getStartIndex(); 7p
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else w{_e"N
return nextIndex; V}vl2o
} N>uA|<b,
8O"x;3I9
publicint getPreviousIndex(){ uAW*5 `[
int previousIndex = getStartIndex() - n@G:e-m{A
@4G.(zW
pageSize; }9L 40)8
if(previousIndex < 0) c%q}"Y0oh
return0; ?&whE!
else |#DC.Ga!
return previousIndex; wQF&GGYR
} {{^Mr)]5K
IeRl6r%:
} W
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抽象业务类 o1fyNzq<
java代码: q#mFN/.(+
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/** {u(}ED#p
* Created on 2005-7-12 '<RB
*/ SX_kr^#
package com.javaeye.common.business; oiTMP`Y
M^|"be~{'
import java.io.Serializable; 4=?Ok":8
import java.util.List; _|^&eT-u
Z4wrXss~
import org.hibernate.Criteria; |1_$!
p
import org.hibernate.HibernateException; R`I8Ud4=
import org.hibernate.Session; +P>
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P&
import org.hibernate.criterion.DetachedCriteria; +WV_`Rx#
import org.hibernate.criterion.Projections; dVj'
import [#STR=_f
:=iM$_tp'
org.springframework.orm.hibernate3.HibernateCallback; h-?q6O/|
import \dp9@y[^
%#S "~)
org.springframework.orm.hibernate3.support.HibernateDaoS By51dk7
=u:6b} =
upport; T>%uRK$
NE=#5?6%g7
import com.javaeye.common.util.PaginationSupport; MrKU,-
v2Qc}o
public abstract class AbstractManager extends ])$."g
@MlU!oR&
HibernateDaoSupport { Mu_mm/U_
7{kpx$:_
privateboolean cacheQueries = false; H/^TXqQ8
:N+#4rtgUY
privateString queryCacheRegion; !Z+*",]_
Fl#VKU3h
publicvoid setCacheQueries(boolean _ RT"1"r
J1c&"Oh
cacheQueries){ RIVL 0Ig
this.cacheQueries = cacheQueries; #T$'.M
} ! 6p)t[s
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publicvoid setQueryCacheRegion(String mP5d!+[8
(4{@oM#H6
queryCacheRegion){ }VGI Y>v
this.queryCacheRegion = Jc"$p\ $-
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queryCacheRegion; $D,
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} jy__Y=1}
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publicvoid save(finalObject entity){ iRj x];:Vu
getHibernateTemplate().save(entity); ^7s6J{<
} TgQ|T57
\HP,LH[P:
publicvoid persist(finalObject entity){ 'Qs3
getHibernateTemplate().save(entity); -MHX1`P:Sn
} qK6
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X_tW#`
publicvoid update(finalObject entity){ IYM@(c@ld0
getHibernateTemplate().update(entity); ,QHx*~9
} )q]j?Z.
G|PIH#
publicvoid delete(finalObject entity){ Xv5Ev@T
getHibernateTemplate().delete(entity); 9h,yb4jPP
} 3]kAb`9[K2
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publicObject load(finalClass entity, t1RwB23
1O3<%T#LOZ
finalSerializable id){ *l?%
o{
return getHibernateTemplate().load K`_E>k
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(entity, id); "$:y03V
} |_xiG~
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publicObject get(finalClass entity, H;7H6fyZ
LWb}) #E
finalSerializable id){ fN*4(yw
return getHibernateTemplate().get VY&9kN
~tj7zI6
(entity, id); f s"V'E2a
} _8b>r1$
pYhI{
publicList findAll(finalClass entity){ ]MA)='~
return getHibernateTemplate().find("from DwrCysIK
~{7NTW
" + entity.getName()); ohtn^o;C}
} 36Z`.E>~L
cV!/
publicList findByNamedQuery(finalString J%[N-
.HyiPx3^
namedQuery){ {FmFu$z+[
return getHibernateTemplate +U/ "F|M
Pymh^i
().findByNamedQuery(namedQuery); nu9k{owB T
} ]aW.b_7<9
TtjSLkF
publicList findByNamedQuery(finalString query, YIk6:W{
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finalObject parameter){ gGdYh.K&e5
return getHibernateTemplate _C8LK.M#j
kuud0VWJ
().findByNamedQuery(query, parameter); :@ 8.t,|
} #<>E+r+
,H(vD,54g
publicList findByNamedQuery(finalString query, +~k,4
i@j ?<
finalObject[] parameters){ :Du{8rV
return getHibernateTemplate vHe.+XY
4_:e+ ql
().findByNamedQuery(query, parameters); W2(=m!:U
} )3\rp$]1
5.HztNL
publicList find(finalString query){ vCo}-b-j
return getHibernateTemplate().find 61wG:
0 S8{VZpy
(query); ';!UJWYl
} H.~+{jTr
,ZW.P`
publicList find(finalString query, finalObject ywtDz8!^u
oqo8{hrdHk
parameter){ Cu<ojN- $
return getHibernateTemplate().find ^n5QKHD
xT(.#9
(query, parameter); by ee-BU
} xW )8mv?4n
-;.fU44O[#
public PaginationSupport findPageByCriteria a2)*tbM9\
=n?@My?;
(final DetachedCriteria detachedCriteria){ m{Xf_rQ
w
return findPageByCriteria a'fb0fz
zMg^2{0L
(detachedCriteria, PaginationSupport.PAGESIZE, 0); yG_.|%e
} Y(mwJud|
T U6EE
public PaginationSupport findPageByCriteria -/*{^[
n9yv.p]
(final DetachedCriteria detachedCriteria, finalint ht!:e>z&4
@WUCv7U
startIndex){ 7En~~J3
return findPageByCriteria %j`]x
-aOz
TJa%zi
(detachedCriteria, PaginationSupport.PAGESIZE, nW[aPQ[R
%tjEVQa
startIndex); "lMWSCas
} R|yTUGY
[)KfRk?};2
public PaginationSupport findPageByCriteria N4FG_N
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(final DetachedCriteria detachedCriteria, finalint eVJL|uI|
[#V!XdQ,
pageSize, {GY$J<5=
finalint startIndex){ |1$X`|S
return(PaginationSupport) 'c]&{-w<i
z oXF"Nz
getHibernateTemplate().execute(new HibernateCallback(){ AS398L
publicObject doInHibernate Oms`i&}"}
={d\zjI$
(Session session)throws HibernateException { 6
>2!
kM7
Criteria criteria = IrK )N
ng\S%nA&J
detachedCriteria.getExecutableCriteria(session); Iu]P^8
int totalCount = ^B>6!
&'j77tqOk
((Integer) criteria.setProjection(Projections.rowCount WbF\=;$=7
4+Kc
()).uniqueResult()).intValue(); pgarGaeq
criteria.setProjection 9)`wd&!
g [K8G
(null); owB)+
List items = q9>w3
<
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criteria.setFirstResult(startIndex).setMaxResults :>u{BG;=79
?2agU
(pageSize).list(); IbC)F> Dq
PaginationSupport ps = auU{Iy
G#>nOB
new PaginationSupport(items, totalCount, pageSize, o@-cT`HP
+yk>jx
startIndex); mD:!"h/
return ps; USY^
[@o[f
} mv_-|N~
}, true); :/08}!_:
} (G
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]H*=Z:riu
public List findAllByCriteria(final 01b0;|
>jm9x1+C
DetachedCriteria detachedCriteria){ G}x^PJJt
return(List) getHibernateTemplate ~PHG5?X
NUseYU``
().execute(new HibernateCallback(){ ~EymD *
publicObject doInHibernate F~6[DqF\|
pbNVj~#6
(Session session)throws HibernateException { X|:O`b$G
Criteria criteria = i@6 kIC
:\Dm=Q\
detachedCriteria.getExecutableCriteria(session); &^"m6
return criteria.list(); o5d)v)Rx=
} @r<w|x}
}, true); )!Bv8&;e
} -Cl0!}P4I
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public int getCountByCriteria(final mi+I)b=
&F)lvtt|
DetachedCriteria detachedCriteria){ ]#;JPO#*
Integer count = (Integer) &7cy9Z~m
8V@3T/}
getHibernateTemplate().execute(new HibernateCallback(){ 3:r;(IaX
publicObject doInHibernate $Khc?v
j`bOJTBE
(Session session)throws HibernateException { 4r %NtXAa
Criteria criteria = 3j6$!89'
&( Z8G~h4
detachedCriteria.getExecutableCriteria(session); N9hBGa$
return My)/d]a
q~lmOT~E
criteria.setProjection(Projections.rowCount Q'Q^K
6<2 7}S
()).uniqueResult(); dS-l2 $n
} r'j*f"uAm
}, true); -YYQnN
return count.intValue(); >R6Me*VR
} [b`k\~N4r
} \ /o`CV{O
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用户在web层构造查询条件detachedCriteria,和可选的 1 #_R`(C{
Av{1~%hU
startIndex,调用业务bean的相应findByCriteria方法,返回一个 +Oo>V~
Rgg(rF=K6
PaginationSupport的实例ps。 &<4Jyhm:o
b}Jcj
ps.getItems()得到已分页好的结果集 ~G"5!,J
ps.getIndexes()得到分页索引的数组 |#"<{RS+w
ps.getTotalCount()得到总结果数 TRa|}JaI"
ps.getStartIndex()当前分页索引 -(dc1?COi
ps.getNextIndex()下一页索引 JPRl/P$
ps.getPreviousIndex()上一页索引 kd2+k4@#
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y<MXd,eE
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V|Smk;G
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A\YP}sG1
*1|&uE&_R
,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 THC34u]
;>bcI).
一下代码重构了。 e~oI0%xl^
R]H/Jv\'
我把原本我的做法也提供出来供大家讨论吧: ~0eJ6i
O1Vs!
首先,为了实现分页查询,我封装了一个Page类: mGb,oj7l
java代码: p{gJVP#l'Z
X)P9f N~7
sk6C/ '0:
/*Created on 2005-4-14*/ &c%;Lo
package org.flyware.util.page; >La!O~d
xj\!Sn2
/** )ERmSWq/u
* @author Joa 8tJB/Pw`S
* 0e-M 24,C
*/ 7b7@"Zw*
publicclass Page { yz.a Z
,6J]oX
/** imply if the page has previous page */ Wb4+U;C^!'
privateboolean hasPrePage; x%@n$4wk7
=wEU+R_#o
/** imply if the page has next page */ p,0J $L
privateboolean hasNextPage; xA/Ein0
F/}(FG<'>I
/** the number of every page */ h'%iY6!fA
privateint everyPage; -y]e`\+[
`3GYV|LeQ
/** the total page number */ 4Cm+xAXG
privateint totalPage; f_'#wc6
J%r$jpd'
/** the number of current page */
vf}.)
privateint currentPage; , !0-;H.Y
IHC
{2 ^
/** the begin index of the records by the current (m:ktd=x
1!/WC.0
query */ f i#p('8
privateint beginIndex; )a99@`L\P
n06T6oc
/N=;3yWF
/** The default constructor */ % XvJJ
public Page(){ A-S!Z2m\
wB%N}bi!
} >_esLsPWh]
4 s&9A/&pC
/** construct the page by everyPage 2d:IYCl4q
* @param everyPage `
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* */ iC(&U YL
public Page(int everyPage){ %0&c0vT
this.everyPage = everyPage; 1>)q5D
} ?xX9o
J) I|Xot
/** The whole constructor */ m0M;f+^
public Page(boolean hasPrePage, boolean hasNextPage, SobOUly5{
8r{:di*
]'q"Kw/10
int everyPage, int totalPage, E'KKR1t
int currentPage, int beginIndex){ QP?eKW9 :
this.hasPrePage = hasPrePage; D2N<a= #
this.hasNextPage = hasNextPage; mto=_|gn
this.everyPage = everyPage; ~Y)h[
this.totalPage = totalPage; N$I@]PL
this.currentPage = currentPage; P[L] S7FTr
this.beginIndex = beginIndex; r
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} xQKRUHDc
fg?4/]*T6
/** qi51'@
* @return myq:~^L
;
* Returns the beginIndex. Ul{{g$
*/ **KkPjAO?
publicint getBeginIndex(){ 7%`
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return beginIndex; ?yNg5z
} P;' xa^Y
X6Wj,a
/** T*3>LY+bb
* @param beginIndex q'9}Hz
* The beginIndex to set. DMXm$PU4V
*/ X}5}M+'~
publicvoid setBeginIndex(int beginIndex){ Gm1[PAj
this.beginIndex = beginIndex; 99/`23YL
} UB9n7L(@c
I UZ@n0/T
/** I&Dp~aEM]
* @return rEfo)jod
* Returns the currentPage. v<u`wnt
*/ iVdY\+N!<
publicint getCurrentPage(){ vj#Y /B
return currentPage; K3I|d;Y~X!
} N*$L#L$*
dd>
qy
/** V'Z Z4og
* @param currentPage Uja`{uc
* The currentPage to set. OF_g0Zu
*/ [+8in\T i
publicvoid setCurrentPage(int currentPage){ yKb+bm&5:'
this.currentPage = currentPage; =ICakh!TO
} d) i64"
Jv[c?6He
/** l2|[
* @return 'jr[
?WQ
* Returns the everyPage. SSH 1Ge5|
*/ PgMU|O7To
publicint getEveryPage(){ E|~)"=
return everyPage; 1RM@~I$0
} ze_q+Z
</B<=tc
/** At$[&%}
* @param everyPage |Ym3.hz
* The everyPage to set. #fQ}8UxU,
*/ z-g"`w:Lj
publicvoid setEveryPage(int everyPage){ P;7
Y9}
this.everyPage = everyPage; 8H7=vk+
} 1Ht&;V
s-lNpOi
/** 0~( f<:
* @return _GF{Duxh
* Returns the hasNextPage. mYRsM s
*/ wRsh@I<
publicboolean getHasNextPage(){ gi#g)9HG
return hasNextPage; 2b89th
} JC#M,j2
MIx,#]C&
/** X :wfmb
* @param hasNextPage 6t!PHA
* The hasNextPage to set. Nay&cOz
*/ =+
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publicvoid setHasNextPage(boolean hasNextPage){ 0CR~ vQf#r
this.hasNextPage = hasNextPage; ve&"x Nz<
} /_{B_2i/>
{,Z-GJ
/** 'fS&WVR?
* @return l)K8.(2
* Returns the hasPrePage. 0T7c =5z4W
*/ mK_2VZj&
publicboolean getHasPrePage(){ dK d"2+fH
return hasPrePage; 6i7+.#s
} mi'3ibCG
HY>zgf,0
/** %k=c9ll@:
* @param hasPrePage ,
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* The hasPrePage to set. +.pri
*/ oUNuM%g9Dy
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; 0qp Pz|h
} MfG8=H2#|
}BN!Xa
/** UB2Ft=
* @return Returns the totalPage. /{%p%Q[X
* t`Lh(`
*/ h,@tfd U^
publicint getTotalPage(){ Boj#r ,x
return totalPage; %n)H(QPW
} 1Rd2Xb
:D:Y-cG*n<
/** mbZn[D_zi
* @param totalPage }CGA)yK~3
* The totalPage to set. %@MO5#)NI
*/ PTP0 _|K
publicvoid setTotalPage(int totalPage){ !$pnE:K
this.totalPage = totalPage; 9(pF!}1%\
} j^6,V\;l
b"pN; v
} EV[ BB;eb
#7Jvk_r9Y
E++3GagdiD
0WQd#l
7Sl"q=>
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 q_86nvB<
zT+ "Z(oz,
个PageUtil,负责对Page对象进行构造: 7-("ppYX=
java代码: 63HtZ=hO7
99*QfC
[Wn6d:
/*Created on 2005-4-14*/ W(o#2;{ln
package org.flyware.util.page; 7bL48W<QD
D!rD-e
import org.apache.commons.logging.Log; (sp{.bU
import org.apache.commons.logging.LogFactory; Pf#DBW*
F5
7Kr5X
/** 3B5 `Y
* @author Joa U-pBat.$'C
* 4P=)u}{]^#
*/ g`I$U%a_2
publicclass PageUtil { ZsN3 MbY
6ANAoWg*
privatestaticfinal Log logger = LogFactory.getLog RU+F~K<
seiE2F[
(PageUtil.class); jwO7r0?\`G
[[uZCKi
/** ?P"j5
* Use the origin page to create a new page 5"z~BE7
* @param page :Fdk`aC
* @param totalRecords [E;~Y_l
* @return }*,z~y}V#
*/ ;"]?&ri
publicstatic Page createPage(Page page, int cB_3~=fV
,B$e'KQ
totalRecords){ So]O`RJv
return createPage(page.getEveryPage(), ALt^@|!d
/_i]bM7W
page.getCurrentPage(), totalRecords); 15ImwQ
} <5npVm
@!::_E+F]
/** Z4{~
* the basic page utils not including exception }0 =gP?.kE
r?}L^bK
handler qhOV>j,d
* @param everyPage QA#Jx
* @param currentPage w%eEj.MI|i
* @param totalRecords Rip[
* @return page w
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*/ `sM^m`yE
publicstatic Page createPage(int everyPage, int /,3:<I
~i=5NUE
currentPage, int totalRecords){ M3YC@(N% k
everyPage = getEveryPage(everyPage); yD(v_J*
currentPage = getCurrentPage(currentPage); e@L?jBj8m
int beginIndex = getBeginIndex(everyPage, p/Ri|FD6
uY:u[
currentPage); P|;=dX#-
int totalPage = getTotalPage(everyPage, jo ~p#l.'
/^b=| +Do
totalRecords); ]-g4Ct_V
boolean hasNextPage = hasNextPage(currentPage, o&kgRv[
kXW$[R
totalPage); 7r$'2">K(
boolean hasPrePage = hasPrePage(currentPage); )Q c>NF0
NXdT"O=P
returnnew Page(hasPrePage, hasNextPage, ux1SQ8C *
everyPage, totalPage, ThYHVJ[;
currentPage, =R0#WMf$@
"U
iv[8B
beginIndex); 7hl,dtn7
} S3&lkN5
z?Qt%1q
privatestaticint getEveryPage(int everyPage){ 99?:
9g
return everyPage == 0 ? 10 : everyPage; Q#sLIZ8=
} |v= */e
8% `Jf`
privatestaticint getCurrentPage(int currentPage){ H(ds
return currentPage == 0 ? 1 : currentPage; Ui05o7xg~p
} 7A4_b8
K)TMr"j\
privatestaticint getBeginIndex(int everyPage, int h}f l:J1C
^:,I #]
currentPage){ b[ .pD3
return(currentPage - 1) * everyPage; 2JLXDkZ
} j$}W%ibj
xQ@gh
( (
privatestaticint getTotalPage(int everyPage, int p$zj2W+sN
KU)~p"0[6]
totalRecords){ <wO8=bem
int totalPage = 0; IjnO2X
W,p?}KiO
T
if(totalRecords % everyPage == 0) ~{f[X3m^
totalPage = totalRecords / everyPage; )L%[(iI,x
else |-.r9;-b
totalPage = totalRecords / everyPage + 1 ; 9xIz[`)i.
l]KxUkA+
return totalPage; 1g bqHxWI
} 8@d,TjJDo
}pL#C
privatestaticboolean hasPrePage(int currentPage){ zua=E2
return currentPage == 1 ? false : true; .lIkJQ3d
} -KFozwr5/
$C~OV@I
privatestaticboolean hasNextPage(int currentPage, Q:sw*7"F
}
2P,Z 6L
int totalPage){ hF7#i_UN<
return currentPage == totalPage || totalPage == qo62!q
"[p-Iy1
0 ? false : true; w}
1~
} sU 5/c|&
vILq5iR
fKjUEMRK
} `w/`qG:dK
*:hHlH* t1
z 2Rg`1B
TE t+At`]
Zh,{e/j
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 FT+[[9i
QeZK&^W
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 (2fWJ% 7VG
FCMV1,
做法如下: UA]U_P$c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Aq:1
^YwTO/Q|
的信息,和一个结果集List: }[m,HA<j
java代码: yPhTCr5pK
1Xj>kE:
L!
DK2,
/*Created on 2005-6-13*/ 8s#2Zv
package com.adt.bo; qL?`l;+
380M&Guh
import java.util.List; G>yTv`-
.PJCBTe
import org.flyware.util.page.Page; (np60mX<
_6k ej#o8
/** HbXYinG%
* @author Joa vRn"0Mzl8
*/ a-<&(jV
publicclass Result { Mp`2[S@$
N);2 2-
private Page page; #2\
0#HN
(^4V]N&
private List content; W|e$@u9
s2rwFj8 |
/** :$J4T;/{
* The default constructor *8?0vkZZ2
*/ AV%t<fDG#
public Result(){ vv%
o+r-t
super(); z1R_a=7
} B(TE?[ #
;H;c Sn5uL
/** AYnk.H-v
* The constructor using fields [9U::
* M~jV"OF=
* @param page R%\K<#^\
* @param content yRF
%SWO
*/ :G\X
public Result(Page page, List content){ eNEMyv5{w4
this.page = page; ^;@Q3~DpP%
this.content = content; aUTXg60l*
} +i0j3.
^D.u
/** 2Sg^SZFH+o
* @return Returns the content. 4ZAnq{nR4
*/ MJDW-KL-
publicList getContent(){ b|KlWt'
return content; %{*A@jQsg
} X}@'FxIF
2YV*U_\L
/** f+xhS,iDR
* @return Returns the page. [')C]YQb=
*/ ^^FqN;
public Page getPage(){ (n+FEE<
return page; +IkL=/';#
} CqkY_z
zlhHSy K
/** "gCqb;^
* @param content (- QvlpZ
* The content to set. [42EqVR
*/ :)eU)r"s4
public void setContent(List content){ @?!&M c2
this.content = content; 8EBy5X}US
} u>y/<9]q8
pX LXkF?
/** Ht_7:5v&
* @param page #x|IEjoa
* The page to set. RAUD8Z
*/ D%%@+3a
publicvoid setPage(Page page){ &RL
j^A!
this.page = page; J7Y lmi
} !0DOj["
} H
b}(.`
?Zv>4+Y'
nKu)j3o`
aP}30E*Y
u`~,`z^{n
2. 编写业务逻辑接口,并实现它(UserManager, 3Q\k!$zq
xwjiNJ Gj
UserManagerImpl) uJ9
hU`h
java代码: ^EFVjGM
<#%kmYSL
55K(]%t
/*Created on 2005-7-15*/ 1}XESAX;0
package com.adt.service; tuIQiWHbM
$s`#&.>c-
import net.sf.hibernate.HibernateException; o)r%4YOL
>V|KS(}s
import org.flyware.util.page.Page; Wa!}$q+
[Zj6v a
import com.adt.bo.Result; @?CEi#-
,/Usyb,`
/** }]!?t~5*
* @author Joa <4,LTB]9-
*/ >yr1wVS
publicinterface UserManager { .0b4"0~T6
^6i,PRScS
public Result listUser(Page page)throws j~C-T%kYa
.\}nDT
HibernateException; qfS
]vc_N
7AuzGA0y
} I6lWB(H!u
* G0I2
,f)#&}x*2+
s^zX9IVnp
3#Qek2
java代码: =QJI_veUG`
>))K%\p
k#DMd9
/*Created on 2005-7-15*/ 8/BWe
;4
package com.adt.service.impl; ukwO%JAr
?CSv;:
import java.util.List; -4LckY=]1
Xn
#v!
import net.sf.hibernate.HibernateException; 9?.
NGL,j\(~7
import org.flyware.util.page.Page; y$`@QRW
import org.flyware.util.page.PageUtil; qi=v}bp&
)m<CmYr2
import com.adt.bo.Result; -APbN(Vi
import com.adt.dao.UserDAO; b<\aJb{2
import com.adt.exception.ObjectNotFoundException; nk.j7tu
import com.adt.service.UserManager; s~g0VNu Y
x03@} M1
/** QUKv :;
* @author Joa s_4y^w]aX
*/ &b9bb{y_$K
publicclass UserManagerImpl implements UserManager { Ux+UcBKm-
c$b~?Mx
private UserDAO userDAO; |}D5q| d@n
'@G=xYR
/** u`Abko<D
* @param userDAO The userDAO to set. O%*:fd,o-
*/ Ngw/H)<c
publicvoid setUserDAO(UserDAO userDAO){ Y^-D'2P]P
this.userDAO = userDAO; ]*TW%mY
} M+GtUE~"
0;Z] vl/|
/* (non-Javadoc) fX{Xw0
* @see com.adt.service.UserManager#listUser 6~tj"34_
fx*Q,}t
(org.flyware.util.page.Page) $*c!9Etl4
*/ ufvjW]
public Result listUser(Page page)throws DT[WO_=
wuKr9W9Xa
HibernateException, ObjectNotFoundException { a+,zXJQYq
int totalRecords = userDAO.getUserCount(); Wo7`gf_ (
if(totalRecords == 0) qx";G
throw new ObjectNotFoundException "9O8#i<Nr
1HBWOV7z.?
("userNotExist"); 4MPR
page = PageUtil.createPage(page, totalRecords); pIl[)%F
List users = userDAO.getUserByPage(page); I]6,hygs
returnnew Result(page, users); -7(,*1Tk
} X]c>clk,
0;tu}]jnN
} CS\8ej}y
0`$fs.4c
&x)n K
uxbLoE
_3zJ.%
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 f6`W(OiE
;"JgNad
询,接下来编写UserDAO的代码: n*r Xj{Kt
3. UserDAO 和 UserDAOImpl: 3v>w$6
java代码: P1dFoQz
y/;DA=
&/8B(0<
/*Created on 2005-7-15*/ E'^ny4gL
package com.adt.dao; TTD#ovo'
2)9XTY6$
import java.util.List; Wn&9R
j
(&Mv!6]
import org.flyware.util.page.Page; %|B$y;q^3
iHeu<3O
import net.sf.hibernate.HibernateException; A@jBn6
-q&7q
/** H^<?h6T
* @author Joa uoTc c|Kc
*/ GjyTM
publicinterface UserDAO extends BaseDAO { wowWq\euY
=\)76xC20
publicList getUserByName(String name)throws xtK}XEhG!
NL &![;
HibernateException; '#lc?Y(pJ2
eN0lJ ~
publicint getUserCount()throws HibernateException; A`1-c
2/ejU,S
publicList getUserByPage(Page page)throws 3{M0iNc1
Lw`}o` D
HibernateException; UaBNoD
\qJ cs'D
} HpS1(%d"
.J?RaH{i
|Elz{i-
c*",AZ>U
d?><+!a
java代码: ge#P(Itz
Sg1,9[pb
5")BCA
/*Created on 2005-7-15*/ c
6/lfgN
package com.adt.dao.impl; 99~ZZG
O^IS:\JX&
import java.util.List; 64D4*GQ
g_)i)V
import org.flyware.util.page.Page; !L)yI#i4C
orhzeOi\
import net.sf.hibernate.HibernateException; GK&R.R]
import net.sf.hibernate.Query; JC9OL.Ob
Vk%W4P"l
import com.adt.dao.UserDAO; Qm4cuV-0{
t![972.&
/** @'"7[k!y;
* @author Joa Tx(=4ALY
*/ <Ys7`e6eY
public class UserDAOImpl extends BaseDAOHibernateImpl \3whM6tK
._<gc;G
implements UserDAO { N|w;wF!3
8xHjdQr
/* (non-Javadoc) jR{t=da
* @see com.adt.dao.UserDAO#getUserByName q,]57s
sNJ?Z"5k1h
(java.lang.String) `!.c_%m2
*/ !%QbE[Kl>
publicList getUserByName(String name)throws f0g&=k{OD
Co`:D
HibernateException { w^/"j_p@
String querySentence = "FROM user in class )T@+"Pw8t
BA_l*h%=Cc
com.adt.po.User WHERE user.name=:name"; qGgdWDn`
Query query = getSession().createQuery ?{>5IjL)en
N~B'gJJDx
(querySentence); K555z+,'e
query.setParameter("name", name); B9oB5E
return query.list(); sJ|IW0Mr
} AmcBu"
0!`!I0
/* (non-Javadoc) CxVrnb[`q
* @see com.adt.dao.UserDAO#getUserCount() op|x~Thf
*/ bfA9aT
publicint getUserCount()throws HibernateException { Wl3fR[@3Q
int count = 0; M:w]g` LKl
String querySentence = "SELECT count(*) FROM VM"*@T
IO?6F@(
user in class com.adt.po.User"; ;\t(c
Query query = getSession().createQuery PSa"u5 O
}fz;La:b
(querySentence); \fL:Ie
count = ((Integer)query.iterate().next dH0wVI<z
I^S{V^Ty
()).intValue(); eXMl3Lxf
return count; D]d2opBLj
} #NWc<Dd
jI807g+
/* (non-Javadoc) |C;*GeyS;J
* @see com.adt.dao.UserDAO#getUserByPage Xr pnc7
^v@&
q
(org.flyware.util.page.Page) U`ELd:
*/ r$-]NYPi
publicList getUserByPage(Page page)throws (+0yZ7AZ
5[$jrG\!
HibernateException {
q=cH ^`<.
String querySentence = "FROM user in class -44''w?z
PiwI.c
com.adt.po.User"; R8R,!3 N
Query query = getSession().createQuery aD8r:S\
B!z5P"C(~
(querySentence); G7H'OB
&
query.setFirstResult(page.getBeginIndex()) *7 >K" j
.setMaxResults(page.getEveryPage()); $9O%,U@
return query.list(); /h73'"SpDy
} p*(]8pDC
wmG[*a_H
} <3c|S_|L*m
d/`Q,Vl
h^"OC$
*>p#/'_E
}z8HS<
#Q
至此,一个完整的分页程序完成。前台的只需要调用 mmrz:_
IEW[VU)
userManager.listUser(page)即可得到一个Page对象和结果集对象 Nb@zn0A(;
6)~J5Fb
的综合体,而传入的参数page对象则可以由前台传入,如果用 6@o *"4~Q
]pP [0S
webwork,甚至可以直接在配置文件中指定。 SV96eYT<
3F6=/
下面给出一个webwork调用示例: 4Fpu68y
java代码: |cUBS)[)X
ThSB\
" tUF,G(<
/*Created on 2005-6-17*/ fbK`A?5K
package com.adt.action.user; -Lbi eS%
_lj&}>l
import java.util.List; @fxDe[J:
Z>zW83a
import org.apache.commons.logging.Log; k3B-;%3I;
import org.apache.commons.logging.LogFactory; OJF41Z
import org.flyware.util.page.Page; c$HZvv
}hv" ku6!
import com.adt.bo.Result; Fxr$j\bm
import com.adt.service.UserService; -<tfbaA
import com.opensymphony.xwork.Action; @"=wn:O+
R59'KR2?
/** >'X[*:Cx
* @author Joa <ny)yK
*/ CsND:m
publicclass ListUser implementsAction{ <..|:0Q&~
I6E!$}
privatestaticfinal Log logger = LogFactory.getLog 12,,gwh
AH#eoKu
(ListUser.class); H(TY.
-O?}-6,_Z
private UserService userService; B:Xmc,|,
~Z#jIG<?g
private Page page; ?yq1\G)]
fmhqm"
privateList users; w_hGWpm
a5AD$bP
/* V=v7<I=]
* (non-Javadoc) _#8OHG.x
* V@"Y"}4n4
* @see com.opensymphony.xwork.Action#execute() &m>sGCZ
*/ \%FEQa0u
publicString execute()throwsException{ kr|u ||
Result result = userService.listUser(page); hvS4"%\
page = result.getPage(); eaxp(VX?oy
users = result.getContent(); 7:D@6<J?
return SUCCESS; eBmBD"$
} ~X`_g/5X
f/Lyc=-]
/** i.e1?Zk1
* @return Returns the page. VNmQ'EuV}2
*/ GuV.7&!x
public Page getPage(){ /*+P}__k
return page; \NEXtr`Th
} xSQ:#o=8G
]d}U68$T+
/** bk-veJR
* @return Returns the users. R*l#[D5A
*/ W]]@pbG"H\
publicList getUsers(){ $fhb-c3
return users; =peodj^
} xb2xl.2x!
vnNX)$f
/** ,-11w7y\
* @param page w&vZ$n-|
* The page to set. R|jt mI?
*/ U.fLuKt
publicvoid setPage(Page page){ ;
S(KJV
this.page = page; PJ-EQ6W
} $Z{ap
"~1{|lj|)
/** vn]e`O>y
* @param users 4=G)j+RCH
* The users to set. }de{-
*/ 9;\a|8O
publicvoid setUsers(List users){ =RA8^wI
this.users = users; "Je*70LG#
} |XDbf3^6
<|!?V"`3
/** JE a~avyJ
* @param userService V<:)bG4;d
* The userService to set. p;y\%i_
*/ CAbeb+O
publicvoid setUserService(UserService userService){ UJ/=RBfkJ
this.userService = userService; $
$=N'Q
} $QNII+o
} W~!uSrY
#nD]G#>e
L[D<e?j
Y"n$d0%
!`A]YcQ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, m0}1P]dc
`kRv+Qwfa
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 SHAC(3o/e
aqw;T\GI+~
么只需要: I+!?~]AUuq
java代码: .|VWYN
<o aVI?
8mmHefZ}2!
<?xml version="1.0"?> z#( `H6n:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fz[-pJ5[
38gHM9T
xh
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $`wo8A|)
J"$Y`;
1.0.dtd"> k"L?("~
>jBa
<xwork> ?a]1$>r
o6v'`p'
<package name="user" extends="webwork- O$K?2-
KE_GC ;bQ
interceptors"> t0"2Si
`J26Y"]P
<!-- The default interceptor stack name m%p;>:"R
?r%kif)
--> :&'[#%h8
<default-interceptor-ref Q+ogV vMq>
%8]~+#]p
name="myDefaultWebStack"/> 1UwpLd
{
ML)F ]]
<action name="listUser" DOa%|H'P
BMJsR0
class="com.adt.action.user.ListUser"> +FGw)>g8'm
<param Yo^9Y@WDW
.zQ'}H1.C
name="page.everyPage">10</param> #
VAL\Z
<result +ak<yV1=
p4sU:
name="success">/user/user_list.jsp</result> tDQo1,(oY
</action> +W}dO#
4*Y`Pn@
</package> z<~yns`Y.
6z3`*B
</xwork> Y2&hf6BE
FC&841F
F./$nwb
~]S%b3>
8HxtmFqG
47yzI-1H+
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 \*i[m&3;q
hI}rW^o^
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 tFrNnbmlQ
[qHtN.
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !IAd.<,
u[b0MNE~
FXO{i:Zo
JM> 4m)h#
rd
hM#?
我写的一个用于分页的类,用了泛型了,hoho _2p D
<HMmsw
java代码: &|#z" E^-
s&Lyg>>`
yT pvKCC
package com.intokr.util; _a&Mk
j"wbq-n,7
import java.util.List; r6:c<p [c
I?#B_ R#
/** VU ,tCTXz
* 用于分页的类<br> r]yI5 ;
* 可以用于传递查询的结果也可以用于传送查询的参数<br> }&