Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 8l0%:6XbI
/Ws@YP
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 d {a^
I2(5]85&]s
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 T+zZOI
|f&)@fUI
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 .R;HH_
UHF.R>Ry
。 &aldnJ
/pZLt)=P
分页支持类: gX5I`mm
dU\,>3tG
java代码: V6?ku6k
$%"i|KTsv:
1 e1$x@\\
package com.javaeye.common.util;
qm&}^S
gYfN?A*`_
import java.util.List; v_"p)4&'
8MGtJ'.
publicclass PaginationSupport { ~cVFCM
deHhl(U;
publicfinalstaticint PAGESIZE = 30; DTk)Y-eQ
\T'uFy9&a
privateint pageSize = PAGESIZE; 11}X2j~Ww
W~k"`g7uu
privateList items; o-Pa3L=
ge9j:S{
privateint totalCount; 9%j_"+<c
N&U=5c`Q'
privateint[] indexes = newint[0]; i)g=Lew
,5HQHo@
privateint startIndex = 0; }BS.OK?
%*lOzC
public PaginationSupport(List items, int Nt9M$?\P
A1zM$
wDU
totalCount){ 1w/1k6`0
setPageSize(PAGESIZE); }$s#H{T!
setTotalCount(totalCount); \dTX%<5D
setItems(items); lcHwKd
setStartIndex(0); rlmzbIuI9
} R<@s]xX_
M5s>;q)
public PaginationSupport(List items, int j|TcmZGO
I4:4)V?
totalCount, int startIndex){ {v+,U}
setPageSize(PAGESIZE); \:-#,( .V
setTotalCount(totalCount); mk8xNpk B
setItems(items); }&Un8Rg"h
setStartIndex(startIndex); G
<
Z)y#
} bO>q`%&
trcG^uV
public PaginationSupport(List items, int :#1{c^i%3
z$$ E7i
totalCount, int pageSize, int startIndex){ >Lx,<sE
setPageSize(pageSize); m.e+S,i
setTotalCount(totalCount); ]l7) F-v
setItems(items); kg?[
setStartIndex(startIndex); R7}=k)U?d@
} R)MWO5
%^f!= *
publicList getItems(){ [ Hw
return items; rXc-V},az8
} L|.q19b*
zgRZgVj
publicvoid setItems(List items){ =B<>H$
this.items = items; r:lv[/D
} iz!E1(z(
~=91Kxf
publicint getPageSize(){ A&X(\ c M
return pageSize; EjW3_ %
} sS(t
}$
&NZl_7PL
publicvoid setPageSize(int pageSize){ =(:{>tO_"
this.pageSize = pageSize; 0YK`wuZGS
} =NLsT.aa
gcDo o2RE
publicint getTotalCount(){ ms2y[b
return totalCount; a3D''Ra
} e f8_w6i
P,U$
X+
publicvoid setTotalCount(int totalCount){ ([SrIG> X
if(totalCount > 0){ \^a(B{
this.totalCount = totalCount; 07 [%RG
int count = totalCount / "}
=RPc%9
2u9O+]EP
pageSize; b5K6F:D22
if(totalCount % pageSize > 0) I,;@\
count++; )rcFBD{vM
indexes = newint[count]; \JmfQrBQ
for(int i = 0; i < count; i++){ )a"rj5~-
indexes = pageSize * .XDY1~w0
U$jw8I'.
i; w/_n$hX
} VQ wr8jXye
}else{ "!43,!<
this.totalCount = 0; \ldjWc<S
} nF$n[:
} z{XN1'/V
&c!d}pU}
publicint[] getIndexes(){ \1|]?ZQ\ K
return indexes; aK>5r^7S
} !kCMw%[
o zg%-
publicvoid setIndexes(int[] indexes){ ZslH2#
this.indexes = indexes; Axp#8
} b{Srd3
.x\fPjB
publicint getStartIndex(){ /){F0Zjjt
return startIndex; |^!#x Tj
} ?^y%UIzf
N6K%Wkz
publicvoid setStartIndex(int startIndex){ .G-F5`2I
if(totalCount <= 0) PL vz1}ts
this.startIndex = 0; FyD^\6/x
elseif(startIndex >= totalCount) /IQl
this.startIndex = indexes wkNf[>jX?
,K4*0!TXP
[indexes.length - 1]; Xc)V;1
elseif(startIndex < 0) %f??O|O3
this.startIndex = 0; h M{&if
else{ 9{&APxm
this.startIndex = indexes ttQX3rmF01
i>=d7'oR
[startIndex / pageSize]; dLA'cQId
} Qa*?iD
} _D{zB1d\0
@ qFE6!
publicint getNextIndex(){ K&1o!<|
int nextIndex = getStartIndex() + u=j|']hp#&
j5hM|\]
pageSize; Mou@G3
if(nextIndex >= totalCount) +Smt8O<N
return getStartIndex(); Q2^~^'Yk
else \1`L-lz
return nextIndex; e|Ip7`
} g;p]lVx=>
z3F ^OU
publicint getPreviousIndex(){ dFdll3bC
int previousIndex = getStartIndex() - }mGOEG|F2
X`xI~&t_
pageSize; MYVUOd,
if(previousIndex < 0) r]! <iw
return0; 7\ .Ax
else PT2b^PP
return previousIndex; [>`[1;a X
} #Bo/1G=
P<+y%g(({
} Znl&.,c)
@\~qXz{6J
44s
K2
]J=S\
抽象业务类 WW.\5kBl8
java代码: L,@OOBD
:V)W?~Z7B
?(8z O"
/** @(:ah
* Created on 2005-7-12 iEDZ\\,
*/ {?a9>g-BW
package com.javaeye.common.business; G5^gwG+
NW-l_]k
import java.io.Serializable; >v4k_JX
import java.util.List; {d|R67~V
.aRL'1xHl
import org.hibernate.Criteria; U3ygFW%
import org.hibernate.HibernateException; OL+!,Y
import org.hibernate.Session; Sr7+DCr
import org.hibernate.criterion.DetachedCriteria; !*46@sb:
import org.hibernate.criterion.Projections; >.R6\>N%
import 9JF*xXd>Q
id^U%4J
org.springframework.orm.hibernate3.HibernateCallback; |pIA9/~Z
import \L#BAB6z
uj.~/W1,!
org.springframework.orm.hibernate3.support.HibernateDaoS Kuh! b`9
]Ll<
upport; a
S-
rng
dEXHd@"H
import com.javaeye.common.util.PaginationSupport; Pn{yk`6E
!'14mN#A
public abstract class AbstractManager extends V/5hEo Dt
h]Zc&&+8{
HibernateDaoSupport { Y^dVNC3vd
Q*TxjE7K
privateboolean cacheQueries = false; m8rz
i:
oz}p]l7
privateString queryCacheRegion; uo1G
d}f| HOFq
publicvoid setCacheQueries(boolean ]{9oB-;,
`Tzqvnn
cacheQueries){ vOYcS$,^X%
this.cacheQueries = cacheQueries; .js4)$W^
} -;$+`<%
+n(H"I7cU
publicvoid setQueryCacheRegion(String ,2>:h"^
t\2myR3
queryCacheRegion){ }@'xEx
this.queryCacheRegion = PN:8H>
/p,D01Ws}(
queryCacheRegion; [5%/{W,~m
} hp(n;(OR
H+zn:j@~L
publicvoid save(finalObject entity){ 7YbI|~
getHibernateTemplate().save(entity); Q}jbk9gM5
} D<7S
P,D
;U<)$5
publicvoid persist(finalObject entity){ *f8,R"]-g
getHibernateTemplate().save(entity); 1at$_\{.(
} i7~oZ)w
yZ&By?.0
publicvoid update(finalObject entity){ F *;
+-e
getHibernateTemplate().update(entity); 1elx~5v1.=
} c: *wev
Tu_dkif'
publicvoid delete(finalObject entity){ hk ./G'E
getHibernateTemplate().delete(entity); #)R;6"
} ,WOF)
#py7emu
publicObject load(finalClass entity, d$r JW m5H
z@y*
jT
finalSerializable id){ Ao96[2U6
return getHibernateTemplate().load 6@2p@eYo
^
+{ ~
^y7
(entity, id); hl~(&D1^
} 1,PFz
F__>`Dol
publicObject get(finalClass entity, C>68$wd>
n 2#uH
finalSerializable id){ tzpGKhrk6
return getHibernateTemplate().get O8u"Y0$*w
>K\ 79<x|
(entity, id); d;#9xD'
} Wc3!aLNx
|[34<tIN
publicList findAll(finalClass entity){ C,PCU <q
return getHibernateTemplate().find("from GWE`'V
hQGZrZK#
" + entity.getName()); P>N\q
} ;JL@V}L,
aDZLabRu
publicList findByNamedQuery(finalString A#1y>k
y6*i/3
namedQuery){ =r0!-[XCa
return getHibernateTemplate 5!nZvv
@oRYQ|.R
().findByNamedQuery(namedQuery); ,A6*EJ\w
} z5'VsK:
WgPL4D9=
publicList findByNamedQuery(finalString query,
7/7A
Wq{' ZN
finalObject parameter){ 0[3b,
return getHibernateTemplate 1}jE?{V*
XVv7W5/q]
().findByNamedQuery(query, parameter); s?Q`#qD
} D"x~bs?V\
rW\~s TH
publicList findByNamedQuery(finalString query, !Rb7q{@>
iBUf1v
finalObject[] parameters){ =m/2)R{
return getHibernateTemplate e9B,
W)4xO>ck*3
().findByNamedQuery(query, parameters); Y" l!3^
} r kD4}jV
<K\F/`c
publicList find(finalString query){ +V'r>C:
return getHibernateTemplate().find +^69>L2V
1$Hf`h2
(query); pP/o2
} '\_)\`a|
}E1Eq
publicList find(finalString query, finalObject !< X_XA
?,8b-U#A1
parameter){ $\K(EBi#G
return getHibernateTemplate().find ^X;>?_Bk
eD(a
+El}
(query, parameter); T ]zjJwa
} g1{wxBFE
# xoFIH
public PaginationSupport findPageByCriteria (@#Lk"B
+es6c')
(final DetachedCriteria detachedCriteria){ ut,"[+J
return findPageByCriteria L%8"d6
plIx""a^h
(detachedCriteria, PaginationSupport.PAGESIZE, 0); P<(mH=K
} QA 9vH'
;yXnPAtJ
public PaginationSupport findPageByCriteria
<?7~,#AK
X'F$K!o*,:
(final DetachedCriteria detachedCriteria, finalint o{Ep/O`
uJ y@
startIndex){ $Yxy(7d7w
return findPageByCriteria )/pPY
5(|ud)v
(detachedCriteria, PaginationSupport.PAGESIZE, HWU{521
bbM
!<&F
startIndex); mT9\%5d3
} sI'HS+~pU
puyL(ohem
public PaginationSupport findPageByCriteria j w462h
>k#aB.6
(final DetachedCriteria detachedCriteria, finalint {2Ibd i
;5l|-&{@*
pageSize, [eN{Ft0x
finalint startIndex){ ,5?MRqCM
return(PaginationSupport) W!^=)Qs
w#$k$T)
getHibernateTemplate().execute(new HibernateCallback(){ J|q_&MX/
publicObject doInHibernate mNYz7N
_L72Ae(_
(Session session)throws HibernateException { xd.C&Dx5
Criteria criteria = ?(=B=a[
$g^;*>yr
detachedCriteria.getExecutableCriteria(session); &Os Ritj
int totalCount = 1GdgF?4
,'6GG+
((Integer) criteria.setProjection(Projections.rowCount TDGzXJf[
`ouzeu9}
()).uniqueResult()).intValue(); f*~fslY,o
criteria.setProjection pk4&-iu9
Jp#cFUa t
(null); `QF|>
N
List items = gD\}CxtG
DIAP2LR ?
criteria.setFirstResult(startIndex).setMaxResults <i6M bCB
19t*THgq
(pageSize).list(); 3Cl9,Z"&6$
PaginationSupport ps = Uf<vw3
8gxLL59
new PaginationSupport(items, totalCount, pageSize, q}i87a;m
y^rg%RV
startIndex); #*/h*GNMs
return ps; Z#O3s:`
} _JDr?Kg
}, true); PsnU5f)`
} C=cTj7Ub
~] 2R+
public List findAllByCriteria(final CQ[-Cp7
9R[','x
DetachedCriteria detachedCriteria){ $C/Gn~k 5
return(List) getHibernateTemplate y|se^dn
Hdx|k=-Q^
().execute(new HibernateCallback(){ '
^^K#f8
publicObject doInHibernate U*TN/6Qy.
s`YuH <8
(Session session)throws HibernateException { 6f!mk:\T.
Criteria criteria = "tARJW
L /> GYx
detachedCriteria.getExecutableCriteria(session); POXn6R!mM1
return criteria.list(); MvmP["%J4_
} ~B@o?8D]
}, true); R2`g?5v
} (^9M9+L[i
;I'/.gW;{
public int getCountByCriteria(final nL!@#{z
B vc=gW
DetachedCriteria detachedCriteria){ %5gJ6>@6Z
Integer count = (Integer) -pu\p-Z
CK</2 w+
getHibernateTemplate().execute(new HibernateCallback(){ 2A|6o*s"
publicObject doInHibernate yFo5 pKF.J
eHe /w9`$R
(Session session)throws HibernateException { `qz5rPyZ
Criteria criteria = .*blM1+6i/
*Rh .s!@4
detachedCriteria.getExecutableCriteria(session); !.$P`wKr
return xk8p,>/
dCTpO
criteria.setProjection(Projections.rowCount P0z{R[KBH
=[+&({
()).uniqueResult(); 5#\p>}[HG
} u_8 22Z
}, true); NGUGN~p
return count.intValue(); AHY)#|/)
} q?4uH;h:^G
} A5ID I<a
Uc0'XPo3I
MlE~gCD
h';v'"DoW`
e&4u^'+K
CD[=z)<z{
用户在web层构造查询条件detachedCriteria,和可选的 )du{ZWr
p9WskYpm
startIndex,调用业务bean的相应findByCriteria方法,返回一个 vh8Kd' y
]#.&f]6l
PaginationSupport的实例ps。 &X,)+b=
%iC63)(M
ps.getItems()得到已分页好的结果集 y03a\K5[KQ
ps.getIndexes()得到分页索引的数组 OZm[iH
ps.getTotalCount()得到总结果数 D.R
ps.getStartIndex()当前分页索引 .G~5F- 8'
ps.getNextIndex()下一页索引 'LLx$y.Ei[
ps.getPreviousIndex()上一页索引 #%"TU,[+
UO<claV
R7c)C8/~
c[lob{,
Ki6.'#%7
1>y=i+T/b
>%dAqYi $
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ibs"Iv34
no6]{qn=6
,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 jdf)bO(9#
wLe&y4
一下代码重构了。 L6=RD<~C
D D;+& fe
我把原本我的做法也提供出来供大家讨论吧: f+Li'?
`Kw8rG\]:
首先,为了实现分页查询,我封装了一个Page类: RmV/wY
java代码: kQl cT"R
=w$"wzc
%E7.$Gj%
/*Created on 2005-4-14*/ z2V8NUn
package org.flyware.util.page; rOr1H!
[W=S8>
/** *js$r+4
* @author Joa W?J[K;<
* S_VncTIO
*/ -f|^}j?
publicclass Page { B2qq C-hw?
.r%|RWs6W
/** imply if the page has previous page */ S&]<;N_B
privateboolean hasPrePage; |Umfq:W`y_
DB'KIw
/** imply if the page has next page */ x0$:"68PW
privateboolean hasNextPage; 6ilC#yyp
]J=)pDrk
/** the number of every page */ T4Gw\Z%
privateint everyPage; 4qXRDsbCf
'=G
Ce%A
/** the total page number */ `oRs-,d|<
privateint totalPage; 8yz((?LrDh
&|"I0|tJ
/** the number of current page */ '!h0![OH
privateint currentPage; h]DECd{
xjq7%R_,
/** the begin index of the records by the current rIfGmh%H
YGV#.
query */ m&~Dj#%(w
privateint beginIndex; @mRrA#E#{
aa%&&
#L=
eK8^e
/** The default constructor */ [d~bZS|(T(
public Page(){ (Cd{#j<
z "$d5XR
} !Fg4Au
"mK i$FV
/** construct the page by everyPage o``>sBZOq
* @param everyPage /A))"D
* */ rjQhU%zv
public Page(int everyPage){ +ls*//R
this.everyPage = everyPage; :tqm2t
} RHl=$Hm.%
v;}`?@G
/** The whole constructor */ [x p,&
public Page(boolean hasPrePage, boolean hasNextPage, !5SQN5K
5~%,u2
A1t~&?
int everyPage, int totalPage, p vQK6r
int currentPage, int beginIndex){ >g"M.gW
this.hasPrePage = hasPrePage; ME@6.*
this.hasNextPage = hasNextPage; h4.=sbzZ
this.everyPage = everyPage; ;zE5(3x
this.totalPage = totalPage; O:=|b]t
this.currentPage = currentPage; J1Ki2I=
this.beginIndex = beginIndex; S O:V|Tfj
} ^N2M/B|0
BS,5W]ervE
/** ,ibPSN5Ca
* @return ssyd8LC#
* Returns the beginIndex. 69j~?w)^
*/ &<|-> *v
publicint getBeginIndex(){ FJ(B]n[>
return beginIndex; oYh<k
} [+MX$y
Xz.Y-5)
/** "3i80R\w`F
* @param beginIndex _X2EBpZp
* The beginIndex to set. =6:L +V
*/ T<e7(=
publicvoid setBeginIndex(int beginIndex){ d:<H?~
this.beginIndex = beginIndex; 'tu@`7*
} /sT
^lf=
cI%"Ynq"3
/** Q6!v3P/h
* @return
^*xHy`
* Returns the currentPage. M |({
4C
*/ )dIfr
publicint getCurrentPage(){ g?[&0r1
return currentPage; Ph+X{|
} z(`
}:t
bA<AG*
/** \aVY>1`
* @param currentPage z'oiyXEE3
* The currentPage to set. d=Df.H+3
*/ jWK@NXMH
publicvoid setCurrentPage(int currentPage){ ?cs]#6^
this.currentPage = currentPage; +fd@K
} K%(XgXb(</
GKyG
#Fl
/** ZG@M%|>
* @return VwOG?5W/
* Returns the everyPage. puS&S
*
*/ m
UWkb
publicint getEveryPage(){ =0PRAc
return everyPage; w &|R5Q
} "o{)X@YN]
I& M36f
/** y3cf[Q
* @param everyPage )b&-3$?
* The everyPage to set. GT'7,+<?N
*/ Zv| p>q`R2
publicvoid setEveryPage(int everyPage){ 0939i_
this.everyPage = everyPage; a%T -Z.rd
} gM3]%L_
/$9BPjO{
/** %/y`<lJz(
* @return Z6^QB@moj
* Returns the hasNextPage.
gmRT1T
*/ .5Knb c
publicboolean getHasNextPage(){ )XP#W|;
return hasNextPage; -.{oqs$
} 4N~+G `
,'C30 A*p
/** ^}o7*
* @param hasNextPage I%9bPQ
* The hasNextPage to set. 3T|Y}
*/ Ts(t:^
publicvoid setHasNextPage(boolean hasNextPage){ j1puB
this.hasNextPage = hasNextPage; -Aa]aDAz68
} /Fe:h>6
e2k4[V
/** % Cu.u)/+
* @return WGh. ;-
* Returns the hasPrePage. wy{ \/?~c
*/ )d +hZ'
publicboolean getHasPrePage(){ U!c]_q
return hasPrePage; a#+>w5
} `l>93A
-=$% {
/** BrJ
o!@<
* @param hasPrePage J ;UBnCg
* The hasPrePage to set. q]6_rY.
*/ Q PFeBl
publicvoid setHasPrePage(boolean hasPrePage){ <t{?7_ 8
this.hasPrePage = hasPrePage; s) Cpi
} JBR[;
zM
'ySljo*It
/** ~n[b^b
* @return Returns the totalPage. =s'XR@
* &:V@2_6"
*/ -B1YZ/.rz"
publicint getTotalPage(){ co5y"yj_
return totalPage; B(j02<-
} 8F zHNG
~->Hlxze'K
/** _i3i HR?
* @param totalPage ,0!uem}1i
* The totalPage to set. l80bHp=
*/ 8p (!]^z
publicvoid setTotalPage(int totalPage){ fokwW}>B[f
this.totalPage = totalPage; fyI_
} D@8jGcz62
+w"_$Tj@;
} aSOU#Csx
J&M1t#UN
5kcJ
?ork^4 $s
cYGRy,'gH
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 F:%^&%\
M
h`CP
个PageUtil,负责对Page对象进行构造: k$C"xg2
java代码: Dp*:Q){>E
K7IyCcdB
Kb}MF9?:e
/*Created on 2005-4-14*/ K~c^*;F
package org.flyware.util.page; 6Wj@r!u
JE0?@PI$
import org.apache.commons.logging.Log; x6LjcRS|
import org.apache.commons.logging.LogFactory; KNy`Lj)VPY
Nd`HB=ShJ
/** R0%?:!
F
* @author Joa $`|5/,M%QN
* -#Np7/
*/ I(pb-oY3!I
publicclass PageUtil { jOs
H2^
BBcj=]"_
privatestaticfinal Log logger = LogFactory.getLog '/k^C9~m
r
Bg-VCJI<
(PageUtil.class); #c-b}.R
MDk*j,5V
/** +%P t_
* Use the origin page to create a new page Qh\YR\O
* @param page m$,,YKhh
* @param totalRecords Rab#7Q16Q8
* @return '9qn*H`'
*/ 2G?$X?
publicstatic Page createPage(Page page, int Vu}806kB
7Yuk
totalRecords){ )o{VmXe@@
return createPage(page.getEveryPage(), yVaU t_Zi
L?!$EPr
page.getCurrentPage(), totalRecords); *ksb?|<Ot
} &.zj5*J
Q:mZ" i5
/** =yo{[&Jz
* the basic page utils not including exception VBM/x|'
J{d(1gSZ
handler UR}kB&t
* @param everyPage i^WIr h3a
* @param currentPage lzEb5mg
* @param totalRecords >9=:sSQu
* @return page Qm<
gb+
*/ vv &BhIf3
publicstatic Page createPage(int everyPage, int iNQ0p:<k
&pM'$}T*
currentPage, int totalRecords){ >V(zJ
everyPage = getEveryPage(everyPage); NvQ%J+
currentPage = getCurrentPage(currentPage); H'EY)s Hi
int beginIndex = getBeginIndex(everyPage, -ui<E?v
QQFf5^
currentPage); u_LY\'n
int totalPage = getTotalPage(everyPage, 34ha26\np
,t1vb3
totalRecords); }p=g*Zo*C;
boolean hasNextPage = hasNextPage(currentPage, aVwH
bg}+\/78#
totalPage); "mOI!xf@a
boolean hasPrePage = hasPrePage(currentPage); # ORO&78
!2$ z *C2;
returnnew Page(hasPrePage, hasNextPage, dAL3. %
everyPage, totalPage, ]dG\j^e|
currentPage, H8f]}
`4V"s-T'
beginIndex); JB^Q\;$
} i.y=8GxY
G`F8!O(
privatestaticint getEveryPage(int everyPage){ <'+ %\
return everyPage == 0 ? 10 : everyPage; ]GX \|1L
} H-I{-Fm
|CIC$2u
privatestaticint getCurrentPage(int currentPage){ jJBnDxsA
return currentPage == 0 ? 1 : currentPage; #r<?v
} 8:thWGLN
.et ^4V3
privatestaticint getBeginIndex(int everyPage, int }"_j0ax
d"ZU y!a
currentPage){ 3F+Jdr'
return(currentPage - 1) * everyPage; BAV>o|-K
} C!&y
,O]l~)sr|
privatestaticint getTotalPage(int everyPage, int 4Po)xo
9S1)U$
totalRecords){ tHh HrMxO
int totalPage = 0; c#lPc>0xb
-.iNNM&a
if(totalRecords % everyPage == 0) |cDszoT
/
totalPage = totalRecords / everyPage; r&%.z*q
else he$XLTmr:
totalPage = totalRecords / everyPage + 1 ; V*RdDF7
}T.?c9l X
return totalPage; Qx)Jtb0`V
} fP[& a9l
!%PWig-
privatestaticboolean hasPrePage(int currentPage){ |c2xy
return currentPage == 1 ? false : true; <G~>~L.E
} $bsH$N#6T
{G3i0r
privatestaticboolean hasNextPage(int currentPage, rNlW7Y
y'}O)lO1
int totalPage){ T9syo/(
return currentPage == totalPage || totalPage == 3s*(uS(
W3rl^M=r
0 ? false : true;
eZL MP
} o''wCr%
iY0>lDFm.
aWy]9F&C:
} z;Q<F
2i7e#
?LaUed'
&:5\"b
xW_yLbE
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。 <rIz Z'D
^ qvZ XS
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 Uxu\u0*
E9}{1A
做法如下: 8VQ 24r
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 yx>_scv,T
ycAKK?O*
的信息,和一个结果集List: a9U_ug58
java代码: )92r{%N
o[1ylzk}+
8K"+,s(%R
/*Created on 2005-6-13*/ bKDA!R2
package com.adt.bo; ][;G=oCT
$`VFdAe
import java.util.List; 57,dw-|xi
a%vrt)Gx
import org.flyware.util.page.Page; nFRsc'VT
:5fAPK2r<
/** l2jF#<S@
* @author Joa k\`S
lb1
*/ :6{`~=
publicclass Result { )|bC^{kH!l
nV_8Ke
private Page page; c#/H:?q?a
V5`^Y=X(%
private List content; &M/>tEZ)
I+(/TP
/** %9v@0}5V
* The default constructor <Fz~7WVd
*/ Dw<k3zaW
public Result(){ +}xaQc:0|
super(); h"+ `13
} \]4v_!
*QGm//b
/** 1O/
g&u
* The constructor using fields t.Nb?/
* 2&!bfq![
* @param page %?Y[Bk3p
* @param content PU<PhuMd
*/ Z{6kWA3Kk
public Result(Page page, List content){ E#wS_[
this.page = page; gJ$K\[+
this.content = content; I@#;nyAj"
} Dnf*7)X
LOy0hN-$b
/** ZraT3
* @return Returns the content. rjx6Djo>
*/ a>O9pX
publicList getContent(){ J%lgR
return content; )\uO9PB[O
} *hLQ
{LHR!~d}5f
/** (~~w7L
s
* @return Returns the page. "es?=
*/ 4NN$( S-W
public Page getPage(){ 7nq3S
return page; <S75($
} ikD1N
[BBEEI=|r
/** *Lqg=9kzr
* @param content 7JJ/D4uT
* The content to set. wIB`%V
*/ "XgmuSQ!
public void setContent(List content){ b89a)k>^g
this.content = content; $j}OB6^I
} \%Ves@hG>
6z0@I*
/** Fs_]RfG
* @param page u c7Eq45
* The page to set. Z/;Xl~
*/ d[p;T\?"
publicvoid setPage(Page page){ L|-98]8>
this.page = page; Q6gt+FKU9
} 1923N]b
}
HB+|WW t>
EtbnE*S
b$%0.s
x<Vm5j
2d%}- nw
2. 编写业务逻辑接口,并实现它(UserManager, ;V^pL((5J
@fv}G>t
UserManagerImpl) ez]tAW
java代码: <JMcIV837
bV8g|l-4(
40E#JF#
/*Created on 2005-7-15*/ 3>E%e!D%
package com.adt.service; #U8rO;$
AfeCK1mC @
import net.sf.hibernate.HibernateException; n1
6 `y}
0Wa}<]:^
import org.flyware.util.page.Page; G,Z^g|6
!q"W{P
import com.adt.bo.Result; toN^0F?Qm
H~ZV*[A`
/** sGh(#A0Pt
* @author Joa 2(5ebe[
*/ qTZFPfyU
publicinterface UserManager { n
-(
su*Pk|6%
public Result listUser(Page page)throws m]i @ +C
kmzH'wktt
HibernateException; 6T 8!xyi-+
DCqY|4Qc
} .ERO|$fv
]Q]W5WDe:
f&v9Q97=
9zYVC[o
ctE\ q
java代码: uqz]J$
}D+}DPL{^
X7k.zlH7T
/*Created on 2005-7-15*/ iq(
)8nxi
package com.adt.service.impl; N?Lb
>pUtwIP
import java.util.List; BIuK @$
\%UkSO\nO3
import net.sf.hibernate.HibernateException; V#VN%{
7{&|;U
import org.flyware.util.page.Page; )K &(
import org.flyware.util.page.PageUtil; %HrAzM.QBF
df7wN#kO+
import com.adt.bo.Result; N F)~W#
import com.adt.dao.UserDAO; :y7c k/>
import com.adt.exception.ObjectNotFoundException; w$JvB5O
import com.adt.service.UserManager; Eke5Nb
3R+|5Uq8~
/** 2-Y<4'>
* @author Joa TB0
5?F
*/ 8M!:N(a
publicclass UserManagerImpl implements UserManager { (5]}5W*
<b,~:9*?
private UserDAO userDAO; pz"0J_xDM
bygx]RC[
/** <&C]sb
* @param userDAO The userDAO to set. pK0"%eA
*/ *6q5S4 r
publicvoid setUserDAO(UserDAO userDAO){ E>l~-PaZY
this.userDAO = userDAO; 9B;{]c
} oJN#C%r7
7uzkp&+:
/* (non-Javadoc) kc0E%odF.v
* @see com.adt.service.UserManager#listUser |i++0BU
6}r`/?"A1
(org.flyware.util.page.Page) 0_ 88V
*/ (o`{uj{!
public Result listUser(Page page)throws A~-b!Grf
2}8v(%s p
HibernateException, ObjectNotFoundException { |\pbir
int totalRecords = userDAO.getUserCount(); oq}'}`lw"
if(totalRecords == 0) !qG7V:6
throw new ObjectNotFoundException $|8!BOx8t
Jv^h\~*jH
("userNotExist"); .V,@k7U,V
page = PageUtil.createPage(page, totalRecords); 9T<x&
List users = userDAO.getUserByPage(page); EFz&N\2
returnnew Result(page, users); eA<0$Gs,h
} J{Q|mD=
~@}Bi@*
} eio4k-
B
{>7-0
rW$[DdFA5{
s0vDHkf8
\-g)T}g,I
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .mR8q+I6
<7~'; K
询,接下来编写UserDAO的代码: q<M2,YrbAI
3. UserDAO 和 UserDAOImpl: nrjE.+v
java代码: a|X a3E
ui?
&v@a5 L
/*Created on 2005-7-15*/ LGn:c;
package com.adt.dao; B6={&7U2
'dn]rV0(C
import java.util.List; !z>6Uf!{
2'w?\{}D
import org.flyware.util.page.Page; \.-bZ$
?32&]iM
oW
import net.sf.hibernate.HibernateException; +~p88;
m^zUmrj[
/** +L;e^#>d
* @author Joa {z{bY\
*/ A6thXs2
publicinterface UserDAO extends BaseDAO { A*\.NTM
5?x>9Ca
publicList getUserByName(String name)throws :;9F>?VN>0
r 8RoE`/T
HibernateException; ,>%}B3O:Y=
%$.3V#?
publicint getUserCount()throws HibernateException; )P
sY($ &
NPp;78O0[
publicList getUserByPage(Page page)throws 'd9INz.
%#kg#@z_`e
HibernateException; a!v1M2>
t7aefV&_,
} HMNLa*CL'
2fL;-\!y(
H*PSR
Y^wW2-,m
fumm<:<CLO
java代码: 50S&m+4d+
_z|65H
C&(N
I
/*Created on 2005-7-15*/ Yo6*C
package com.adt.dao.impl; ``hf=`We
gtppv6<Mj4
import java.util.List; D9H?:pmv?
asppRL||
import org.flyware.util.page.Page;
"y}--
W:pIPDx1=!
import net.sf.hibernate.HibernateException; V@g'#={r
import net.sf.hibernate.Query; )6Fok3u
uxr #QA
import com.adt.dao.UserDAO; _9F9W{'
o6.^*%kM'
/**
f*?]+rz
* @author Joa iP7(tnlW$
*/ rX2.i7i,
public class UserDAOImpl extends BaseDAOHibernateImpl (@fHl=! Za
!$gR{XH$]
implements UserDAO { )"7iJb<E
AP 2_MV4W
/* (non-Javadoc) Pd_U7&w,5
* @see com.adt.dao.UserDAO#getUserByName !Dn,^
at,XB.}Z]
(java.lang.String) 4O^xY
6m
*/ 8;JWK3Gv
publicList getUserByName(String name)throws '-Vt|O_Q
I 5^!y
HibernateException { I;wp':
String querySentence = "FROM user in class t.i 8
2Q
;DfY#-
com.adt.po.User WHERE user.name=:name"; _@
qjV~%Sy
Query query = getSession().createQuery 286jI7 T
vApIHI?-
(querySentence); G[uK -U
query.setParameter("name", name); (x;@%:3j$
return query.list(); <L8'! q}
} oqO(PU
@@Kp67Iv
/* (non-Javadoc) 8V`WO6*
* @see com.adt.dao.UserDAO#getUserCount() 6d<r= C=
*/ aC8} d
publicint getUserCount()throws HibernateException { vXrx{5gz
int count = 0; YYBDRR"
String querySentence = "SELECT count(*) FROM (c=6yV@
\ C+~m
user in class com.adt.po.User"; 1#< '&Lr
Query query = getSession().createQuery 7x|9n
?N *>*"
(querySentence); ?]_$Dcmx
count = ((Integer)query.iterate().next bN1|q|9
f@wquG'
()).intValue(); KQ!8ks]
return count; <KL,G};0pm
} BYL)nCc
/T0F"e)Ci
/* (non-Javadoc) 1Y\DJ@lh
* @see com.adt.dao.UserDAO#getUserByPage ) j#`r/
4DI8s4fi
(org.flyware.util.page.Page) 2*;~S44
*/ H)kwQRfu
publicList getUserByPage(Page page)throws 7rc0yB
o,\$ZxSlm
HibernateException { :+^lJ&{U
String querySentence = "FROM user in class *K8$eDNZ
hd%Fnykq
com.adt.po.User"; 'uSn}hm
Query query = getSession().createQuery NX*Q F+
UNu#(nP
(querySentence); dVtG/0
query.setFirstResult(page.getBeginIndex()) 6_GhO@lOG
.setMaxResults(page.getEveryPage()); *5C7d*'
return query.list(); g[' ^L+hd
} qZ}^;)a^
vxBgGl
} C!<Ou6}!b
XPXIg
)4 e.k$X^
_YhES-Ff
l` lk-nb
至此,一个完整的分页程序完成。前台的只需要调用 cJ=6r
:
q_[o"wq/
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]nn98y+
%D{6[8
的综合体,而传入的参数page对象则可以由前台传入,如果用 i
&nSh ]KK
]g3JZF-
webwork,甚至可以直接在配置文件中指定。 BO?%'\
zZPO&akB"
下面给出一个webwork调用示例: :1QI8%L'$i
java代码: =7=]{Cx[
Uiw2oi&_
5uGq%(24
/*Created on 2005-6-17*/ nfbR
P t
package com.adt.action.user; GY'%+\*tj
#jvtUS \
import java.util.List; L\J;J%fz.
`,<BCu
import org.apache.commons.logging.Log; hn
GZ=
import org.apache.commons.logging.LogFactory; ;WQve_\
import org.flyware.util.page.Page; Ua: sye
gD@){Ip
import com.adt.bo.Result; lgL%u K)
import com.adt.service.UserService; BA:VPTZq
import com.opensymphony.xwork.Action; N)X3XTY
Hk3sI-XkA
/** Woym/[i
* @author Joa I^-Sb=j?Z
*/ S&wMrQ
publicclass ListUser implementsAction{ WaRw05r
03X1d-
privatestaticfinal Log logger = LogFactory.getLog Jq-]7N%k/
7;(`MIFXs
(ListUser.class); ^}=,g
~Fcm[eoC
private UserService userService; !c
Hum
k(nW#*N_
private Page page; q6luUx,@m
l_d5oAh
privateList users; _
]ipajT
+SU8 +w
/* F v2-(
* (non-Javadoc) "%w u2%i
* +{.WQA}z\
* @see com.opensymphony.xwork.Action#execute() By!o3}~g
*/ cKI9#t_
publicString execute()throwsException{ 'rkdZ=x{
Result result = userService.listUser(page); zR:L!S
page = result.getPage(); F@KGj|
users = result.getContent(); &K#M*B,*p
return SUCCESS; ""G'rN_=Bi
} .uZ3odMlx
oJz^|dW
/** +mj y<~\
* @return Returns the page. $qnZl'O>
*/ QA`sx
public Page getPage(){ ;A'mB6?%H
return page; E{`fF8]K
} r),kDia
R&k<AZ
/** tS=(}2Q
* @return Returns the users. ;*Et[}3
*/ ea
'D td
publicList getUsers(){ /(*q}R3Kfo
return users; !l8PDjAE
} 0'C1YvF
*.t7G
/** q>+k@>bk@
* @param page VY4yS*y
* The page to set. uy$e?{Jf
*/ JK5gQ3C[
publicvoid setPage(Page page){ pl?`8@dI
this.page = page; VpDbHAg
} 9W2Vo [(
on`3&0,.
/** )3EY;
* @param users hz@bW2S.
* The users to set. W^l-Y%a/o
*/ Qp3_f8
publicvoid setUsers(List users){ `d}2O%P
this.users = users; oUU1+F-
} ^<2p~h0
\
p<"m[Dt]
/** &V/MmmT
* @param userService (O3nL.
* The userService to set. t'ql[
*/ UP,c |
publicvoid setUserService(UserService userService){ -[.[>&`/
this.userService = userService; H G^'I+Yn
} 1=V-V<
} ~Mxvq9vaD
T_4/C2
2J BR)P
0 kW,I
&%J08l6
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, X'iWJ8
S"H2 7
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
.?$gpM?i
4.t-i5
么只需要: FQ\h4` >B
java代码: zTU0HR3A
3[*}4}k9
H4+i.*T#
<?xml version="1.0"?> ep{FpB
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]h5tgi?_l
PEZ!n.'S
1.0//EN" "http://www.opensymphony.com/xwork/xwork- oOFVb5qoFU
fz
"Y CHe
1.0.dtd"> 61U09s%\0
pEA:L$&
<xwork> F:S}w
S?2>Er
<package name="user" extends="webwork- =T7.~W
Y.p;1"
interceptors"> LKDO2N
_H@DLhH|=
<!-- The default interceptor stack name GZIa4A
}O
p;
g^W
--> u>vL/nI
<default-interceptor-ref X^j fuA
Xsa].
name="myDefaultWebStack"/> 3!_XEN[
& 1f+,
<action name="listUser" dSHDWu&
G18b$z
class="com.adt.action.user.ListUser"> TB31-
()
<param La[V$+Y
ZbKg~jdF
name="page.everyPage">10</param> `Urhy#LC
<result FGzwhgy
0w7DsPdS
name="success">/user/user_list.jsp</result> ?}Y]|c^W
</action> q!@4~plz
pd$[8Rmj_
</package> _lq`a\7e
Tw<q,O
</xwork> 6_B]MN!(
x
kD6Iw
MF'JeM;H
6ik$B
'~ 47)fN
.T`%tJ-Em
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 <1TAw.
F8ulkcD
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。 ;$Jo+#
~&uHbTq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Dw"\/p:-3
7zj{wp!
&H+xzN
'Pbr
v
rPm x
我写的一个用于分页的类,用了泛型了,hoho uXiN~j &Be
?e?!3Bx;EM
java代码: t_1LL >R
/x *3}oI
3XNCAb2
package com.intokr.util; 7d\QB(~
* v#o
import java.util.List; rvM {M/4
nJ;.Td
/** m4Zk\,1m.|
* 用于分页的类<br> -nwypu
* 可以用于传递查询的结果也可以用于传送查询的参数<br> F"mmLao
* %"-5 <6d
* @version 0.01 %z$#6?OK^
* @author cheng !()Qm,1u
*/ 5mR 1@
public class Paginator<E> { J .<F"r>
privateint count = 0; // 总记录数 1\.pMHv/
privateint p = 1; // 页编号 ?V=CB,^
privateint num = 20; // 每页的记录数 !
dgNtI@
privateList<E> results = null; // 结果 1Z&(6cDY8M
W*Y/l~x}
/** glw+l'@
* 结果总数 Ho]su?
*/ ,]D,P
publicint getCount(){ 2Khv>#l
return count; =EsavN
} \{YU wKK/A
s#GLJl\E_P
publicvoid setCount(int count){ _e2=ado
this.count = count; 'N(R_q6MW
} G+m }MOQP7
GA.8@3
/** z(~_AN M4,
* 本结果所在的页码,从1开始 D6Wa.,r
* 2&5K.Ui%
* @return Returns the pageNo. H,NF;QPPC
*/ rT>wg1:
publicint getP(){ Alq(QDs
return p; @}ZVtrz
} 6dYMwMH
*NQ/UXE
/** V.2_i*
* if(p<=0) p=1 e}W)LPR!
* H"F29Pu2
* @param p mp3s-YfRc
*/ #LNED)Vg
publicvoid setP(int p){ e#q}F>/L
if(p <= 0) P2nu;I_&
p = 1; Yr|4Fl~U
this.p = p; !Z6{9sKR=]
} o !7va"
d"Y{UE
/** d d;T-wa}
* 每页记录数量 fB,_9K5i
*/ P'rb%W
publicint getNum(){ S]{oPc[7
return num; K>
e7pu
} >R=|Wo`Ri
wKHBAW[i]
/** fXB0j;A
* if(num<1) num=1 `F6C-
*/ p b,. r
publicvoid setNum(int num){ fc@A0Hf
if(num < 1) &m vSiyKX
num = 1; 048kPXm`
this.num = num; ch]29
} wyG;8I
:Tq~8!s
/** [/ZO q
* 获得总页数 :hA#m[
*/ E\$W_Lmr
publicint getPageNum(){ Q@H V- (A
return(count - 1) / num + 1; Y\tui+?J
} !&\INl-Z
tnIX:6
/** g=I})s:CTp
* 获得本页的开始编号,为 (p-1)*num+1 |cY`x(?yP
*/ GKCroyor
publicint getStart(){ 2"~8Z(0
return(p - 1) * num + 1; :Qq#Z
} {XHh8_^&
O
H7FkR
/** =w^M{W.w
* @return Returns the results. S[QrS7
*/ E)3NxmM#
publicList<E> getResults(){ )}ROLe
return results; (iGTACoF
} B?wq=DoG
2+O'9F_v
public void setResults(List<E> results){ Wez5N
this.results = results; Q=:|R3U/
} BORA(,
U;I9 bK8
public String toString(){ Aa]"
StringBuilder buff = new StringBuilder t:c.LFrF
-.3w^D"l
(); uVU)d1N
buff.append("{"); zn(PI3+]!
buff.append("count:").append(count); Ct|A:/z(
buff.append(",p:").append(p); A70d\i
buff.append(",nump:").append(num); 'H!XUtFs"
buff.append(",results:").append FgI3
l+0P
(results); ?hM64jI|
buff.append("}"); /Q )\ +
return buff.toString(); j~QwV='S
} Qei"'~1a
{ "E\Jcjl\
} RGX=)
c"xK`%e
UZ$/Ni