Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +j<WP
X2Ak
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Zb1GR5MB`k
PdO"e
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 qA7,txQ:
[IOI&`?D
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 y{mt *VA4
GW>F:<p
。 &qXobJRM
=H;n$ -P
分页支持类: QHO n?e
cN&Ebn
java代码: -rcEG!
E6~VHQa2?
q&@s/k
package com.javaeye.common.util; SzpUCr"
&{8:XJe*,%
import java.util.List; zy$jTqDH
$jh$nMx)!
publicclass PaginationSupport { RM_%u=jC
9)tb=
publicfinalstaticint PAGESIZE = 30; _\+]/rY9o
|k6+-
1~_
privateint pageSize = PAGESIZE; N/0aO^"V
:} =lE"2
privateList items; [ x{$f7CEh
SV t~pE+Y
privateint totalCount; 1<m`38'
L-?ty@-i
privateint[] indexes = newint[0]; x*z[(0g!
+C!GV.q[
privateint startIndex = 0; QYo04`Rl
WZ?>F
public PaginationSupport(List items, int }TMO>eB'
N@PwC(
totalCount){ K9xvog
setPageSize(PAGESIZE); #>aq'47j
setTotalCount(totalCount); 0a:oC(Ak
setItems(items); `:3nF'
setStartIndex(0); ?X|q
} {ax]t-ZwJ5
r*b+kSh
public PaginationSupport(List items, int Fvk=6$d2
%|H]T]s
totalCount, int startIndex){ O
MQ?*^eA
setPageSize(PAGESIZE); )=GPhC/sw
setTotalCount(totalCount); #^VZJ:2=|
setItems(items); @*vVc`;
setStartIndex(startIndex); zl8M<z1`1
} i=<;$+tW
cu>(;=
public PaginationSupport(List items, int }6a}8EyFP
)@DDs(q=i
totalCount, int pageSize, int startIndex){ =!SV;^-q
setPageSize(pageSize); 5;KJ0N*-
setTotalCount(totalCount); -51LF=(!L
setItems(items); 5T.U=_ag
setStartIndex(startIndex); P0>2}/;o
} -'qVnu
I;JV-jDM
publicList getItems(){ i;{lY1
return items; '/qy_7O
} *CXc{{
LGuZp?"
publicvoid setItems(List items){ MkMDI)Y|
this.items = items; $Z)u04;&@
} +r"}@8/\1
Szt2 "AR
publicint getPageSize(){ $$ *tK8#
return pageSize; u_NLgM7*
} KJyCfMH&:@
A{\?]]/
publicvoid setPageSize(int pageSize){ 9Zd\6F,
this.pageSize = pageSize; B0|W
} QBGm)h?=
_Vp"G)1Y
publicint getTotalCount(){ *y?6m,38V
return totalCount; 0^S$_L
} DcBAncsK
(y;
6H
publicvoid setTotalCount(int totalCount){ stK}K-=`
if(totalCount > 0){ 0'6ai=W
this.totalCount = totalCount; d`rZgY
int count = totalCount / MuMq%uDA"
j"6|$Ze8
pageSize; #b*4v&<
if(totalCount % pageSize > 0) jC[_uG
count++; Q(-&}cY
indexes = newint[count]; 8>WA5:]v
for(int i = 0; i < count; i++){ 5QK%BiDlr
indexes = pageSize * &o x
+pG+ xI
i; V/H+9+B7Im
} 2F*>&n&Db7
}else{ zx<PX
this.totalCount = 0; db,?b>,EE
} 8<}=f4vUj5
} AJ6l#j-
(" :Dz_
publicint[] getIndexes(){ `Gv\"|Gn
return indexes; uz+WVmb
} 2iM}YCV
O EaL2T
publicvoid setIndexes(int[] indexes){ #&)H&H}
this.indexes = indexes; pW.WJ`Rk
} octQ[QXo#
qvu1 u
GCc
publicint getStartIndex(){ mvH8hvD9
return startIndex; ?3K~4-!?/
} $\*Z
Mm*V;ADF
publicvoid setStartIndex(int startIndex){ OWrQKd
if(totalCount <= 0) 4G I3|{
this.startIndex = 0; F%a&|X
elseif(startIndex >= totalCount) D"aK;_W@h
this.startIndex = indexes eik_w(xPT
tnUfi8\ob
[indexes.length - 1]; wbF`wi?
elseif(startIndex < 0) er24}G8
this.startIndex = 0; !%M,x~H
else{ }0\SNpVN
this.startIndex = indexes xdbzpU
s"#N;
[startIndex / pageSize]; 4vi?9MPz
} bL* b>R[x
} Gr\jjf`
[;IE Z/ZX
publicint getNextIndex(){ L&s~j/pR
int nextIndex = getStartIndex() + AJ>E\DK0]
c-JXWNz
pageSize; mZB:j]T
if(nextIndex >= totalCount) \Y"S4<"R
return getStartIndex(); 0cKsGDm
else 2;T?ry7
return nextIndex; WqefH{PB
} +o4o!;E)
J'|[-D-a
publicint getPreviousIndex(){ 4|&/#Cz^Y
int previousIndex = getStartIndex() - Czw]5
:'%|LBc0
pageSize; |MKR&%Na
if(previousIndex < 0) kJ"rRsK
return0; 0~ nCT&V
else Z<>gx m<
return previousIndex; 7r?,wM
} Y>aVnixx<
1Q
FsT
} 1lIs
jBo g
IY6Ll6OK
X%s5D&gr
wN'S+4
抽象业务类 n:40T1:q
java代码: ,=C ipL9]
_+P*XY5
0
N7I:vJ
/** ~SBW`=aP}
* Created on 2005-7-12 9;XbyA]
*/ MVzj7~+
package com.javaeye.common.business; gYN;Fu-9Z
XGR63hXND
import java.io.Serializable; XM!oN^
import java.util.List; "Cxj_V@\
16eP7s
import org.hibernate.Criteria; }2 S!;swg+
import org.hibernate.HibernateException; -"ZNkC=
import org.hibernate.Session; En7+fQ
import org.hibernate.criterion.DetachedCriteria; )G/=3;!
import org.hibernate.criterion.Projections; ESoqmCJjb:
import i#YDdz
yxx_%9 X
org.springframework.orm.hibernate3.HibernateCallback; 4w%hvJ
import z)KoK`\mE"
(9( xJ)
org.springframework.orm.hibernate3.support.HibernateDaoS {(-923|,
i| cA)
upport; n1|]ji[c
+7OE,RoQ
import com.javaeye.common.util.PaginationSupport; W:n\,P
;Co"bP's
public abstract class AbstractManager extends Mfz(%F|<
<5KoK!H
HibernateDaoSupport {
VJK4C8]
b?0WA.[{
privateboolean cacheQueries = false; J6EzD\.Y)
hU(
privateString queryCacheRegion; \I i#R
$#e}9g.
publicvoid setCacheQueries(boolean \4$Nx/@Q}
?~.9:93
cacheQueries){ jS3@Z?x?*
this.cacheQueries = cacheQueries; o/
\o-kC}
} `::j\3B&Y-
Us "G X_
publicvoid setQueryCacheRegion(String #q34>}O< O
6T~+vT
queryCacheRegion){ Kg2@]J9m
this.queryCacheRegion = Vt zSM%=
xF) .S@
queryCacheRegion; *]q`:~u2
} oU3gy[wF;b
n @@tO#!\
publicvoid save(finalObject entity){ tZ=|1lM
getHibernateTemplate().save(entity); ^{yb4yQ
0
} )N{PWSPs
8z=o.\@
publicvoid persist(finalObject entity){ "e\73?P
getHibernateTemplate().save(entity); O+XQP!T
} HWoMzp5="3
< :eKXH2
publicvoid update(finalObject entity){ PTpCiiA@
getHibernateTemplate().update(entity); $aXYtHI
} .ZQXY%g
2mj>,kS?c
publicvoid delete(finalObject entity){ |OF3J,q
getHibernateTemplate().delete(entity); bU}!bol
} jj `0w@
T2W^4)
publicObject load(finalClass entity, -=rGN"(M
_
/s)It
finalSerializable id){ 25, [<Ao
return getHibernateTemplate().load ;ACeY
{Q K9pZB
(entity, id); k]& I(VQ"
} Obc,
N]c:8dOj
publicObject get(finalClass entity, h;K9}w
:1iXBG\
finalSerializable id){ <9=RLENmY"
return getHibernateTemplate().get .
VI
#
Jl"DMUy[kW
(entity, id); t@cBuV`9c
} /KvpJ4
\hzx?
publicList findAll(finalClass entity){ d9D*w/clMi
return getHibernateTemplate().find("from $[=`*m
JLyFkV/
" + entity.getName()); OK}8BY
} gJOswN;([
)[sSCt]
publicList findByNamedQuery(finalString #@5 jOi
CA"`7<,
namedQuery){ &E
k\
return getHibernateTemplate wAb_fU&*
GEb)nHQq
().findByNamedQuery(namedQuery); |("5 :m
} hW cM.
XnvaT(k7Y
publicList findByNamedQuery(finalString query, <* PjG}Z.
xi\uLu?i
finalObject parameter){ hi]\M)l&x
return getHibernateTemplate v#sx9$K T
^T@-yys
().findByNamedQuery(query, parameter); .fW`/BXE
} V|0UwS\n
VKrKA71Z~
publicList findByNamedQuery(finalString query, Z3T26Uk
7xT<|3 I
finalObject[] parameters){ R91u6r#
return getHibernateTemplate
D3 E!jQ1
t;ga>^NA"
().findByNamedQuery(query, parameters); s{j3F
} zwHTtE
p/s5[>N
publicList find(finalString query){ CV7.hF<
return getHibernateTemplate().find z!j`Qoh?V9
wA)R7%&
(query); XlNB9\"5
} aR;Q^YJ+a
?at~il$z'
publicList find(finalString query, finalObject {la^useg[
R?\8SdJ
parameter){ Un[#zh<4
return getHibernateTemplate().find 8c$IsvJg
&l|B>{4v
(query, parameter); 9zd)[4%=
} (C QgT3V
IPE(
public PaginationSupport findPageByCriteria 55N/[{[
a. 5`Q2
(final DetachedCriteria detachedCriteria){ 3vs2}IV'
return findPageByCriteria !*#=7^#
<$9AP
(detachedCriteria, PaginationSupport.PAGESIZE, 0); X!_OOfueP8
} Kd,m;S\
n#]G!7
public PaginationSupport findPageByCriteria -)<Nd:A
%BHq2~J
(final DetachedCriteria detachedCriteria, finalint h;unbz
p-/x Md
startIndex){ pV-.r-P
return findPageByCriteria qC|re!K
$S cjEG:6
(detachedCriteria, PaginationSupport.PAGESIZE, d ly 0874
Ip1QmP
startIndex); ;[zx'e?!
} ;NPb
%r,2ZLZ
public PaginationSupport findPageByCriteria *'t`;m~
}&naP
(final DetachedCriteria detachedCriteria, finalint KJkcmF}Q
&
='uAw
pageSize, Ia"bP` L
finalint startIndex){ :3Jh f$
return(PaginationSupport) I5"=b}V5
Rx<pV_|H,
getHibernateTemplate().execute(new HibernateCallback(){ XKK*RVs#
publicObject doInHibernate <(t<gS #
F^~#D, \
(Session session)throws HibernateException { E|Lh$9XONA
Criteria criteria = n*xNMw1x"T
bU,&|K/
detachedCriteria.getExecutableCriteria(session); BPOWo8TqD^
int totalCount = ) D`_V.,W
BZ T%+s;u9
((Integer) criteria.setProjection(Projections.rowCount &boBu^,94
q.X-2jjpx:
()).uniqueResult()).intValue(); Zj^H3h
criteria.setProjection Ek.j@79
RGKJO_*J2
(null); 5LK>n-
List items = ]-`{kX
\%VoX`B
criteria.setFirstResult(startIndex).setMaxResults 5m3sjcp_
8ksDXf`.
(pageSize).list(); \ d;Ow8%d/
PaginationSupport ps = LMDa68 s
8+ W^t I
new PaginationSupport(items, totalCount, pageSize, )G|UB8]
Mt:(w;Y
startIndex); `'QPe42
return ps; u@3w$"Pv1
} ZtT`_G&
}, true); pL-$Np] V
} ={oO9.9
i
xyjl[G
public List findAllByCriteria(final 1FX-#Y`e
`jkn*:m
DetachedCriteria detachedCriteria){ mnia>;
0H
return(List) getHibernateTemplate J{ Vl2P?@
#75;%a8
().execute(new HibernateCallback(){ Mf63 59
publicObject doInHibernate tpctz~ .
*dl@)~i
(Session session)throws HibernateException { WQ]pg
"
Criteria criteria = ] ge-b\
`F@yZ4L3S
detachedCriteria.getExecutableCriteria(session); \3/9lE|gh
return criteria.list(); Pg36'aTe%j
} /P%:u0fX,
}, true); >JMKEHl.q
} S'e2~-p0F
Ui.F<,E
public int getCountByCriteria(final aU! UY(
@mazwr{B
DetachedCriteria detachedCriteria){ -wt2ydzos
Integer count = (Integer) V]2z5u_q
kShniN
getHibernateTemplate().execute(new HibernateCallback(){ ^pP
14y*go
publicObject doInHibernate gs3}rW
A.FI] K@
(Session session)throws HibernateException { 73.b9mF
Criteria criteria = m~K]|]iqQ
zl[JnVF\6
detachedCriteria.getExecutableCriteria(session); {mQJ6
G'ny
return #@fypCc
gr=`_k4~1
criteria.setProjection(Projections.rowCount >seB["C
BSY#xe V
()).uniqueResult(); SOL=3hfb^
} ~83P09\T%
}, true); 1DP)6{x
return count.intValue(); yN.D(ZwF:
} ik*_,51Zj
} ,L;vN6~
;<A/e
Vmc)or*#
ZJ(!jc$"*%
aBnbu
vp
ccSS au5N
用户在web层构造查询条件detachedCriteria,和可选的 $\
'\@3o
G;;~xfE'
startIndex,调用业务bean的相应findByCriteria方法,返回一个 96avgyc
luT8>9X^:a
PaginationSupport的实例ps。 86g+c
LayU)TIt
ps.getItems()得到已分页好的结果集 8g NEL+
ps.getIndexes()得到分页索引的数组 nmGHJb,$
ps.getTotalCount()得到总结果数 a5M>1&j/eC
ps.getStartIndex()当前分页索引 <GN?J.B
ps.getNextIndex()下一页索引 De_</1Au!2
ps.getPreviousIndex()上一页索引 as4NvZ@+r
%-Z~f~<?
w$4Lu"N:
O|~'-^
xJhbGK
`,Gk1~Wv
[
UJj*n
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8.':pY'8"
C.-a:oQ[
,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 o{p_s0IX;S
3XtGi<u
一下代码重构了。 @UJmbD{
^@2Vh*k
我把原本我的做法也提供出来供大家讨论吧: vNbA/sM
mtHz6+
首先,为了实现分页查询,我封装了一个Page类: $@)d9u
cd
java代码: HV.7IyBA^
X;:xGZ-oY
3)a29uc:U
/*Created on 2005-4-14*/ ltR^IiA}
package org.flyware.util.page; <4,?lZ
FF/R_xnx
/** uw!|G>
* @author Joa lv*uXg.k^
* 8)8oR&(f
*/ N~jQ!y
publicclass Page { 5nAF =Bj
[)~@NN
/** imply if the page has previous page */ 1.uQ(>n
privateboolean hasPrePage; su;S)yZb
a7G2C oM8
/** imply if the page has next page */ di2=P)3
privateboolean hasNextPage; /g''-yT7#
ASw|sw
/** the number of every page */ ':]a.yA\1
privateint everyPage; N-E`go
RfG$Px '
/** the total page number */ +hgCk87%#
privateint totalPage; <v k$eB8EC
Ai18]QD-
/** the number of current page */ u$8MVP
privateint currentPage; Cl!jK^AbG
{1|7N
GQ
/** the begin index of the records by the current ZF(=^.gc
V JL;+
query */ W2h[NimU
privateint beginIndex; l$_rA~Mo
z&,sm5Lb
T
l(uqY?9
/** The default constructor */ |9]K:A
public Page(){
Tpx,41(k
#9VY[<
} #/<Y!qV&
4 GW[GT
/** construct the page by everyPage g}QTZT8
* @param everyPage I>Fh*2
* */ a&Du5(r;!
public Page(int everyPage){ XF$]KAL0
this.everyPage = everyPage; Tk&9Klo
} %nf=[f
s,H(m8#>
/** The whole constructor */ C)p<M H<
public Page(boolean hasPrePage, boolean hasNextPage, %5?-g[
&W//
Ox
)f
iGVb.=)
int everyPage, int totalPage, #-j!
;?
int currentPage, int beginIndex){ B-'BJ|*4I
this.hasPrePage = hasPrePage; _4B iF?1
this.hasNextPage = hasNextPage; n@[</E(
this.everyPage = everyPage; .BDRD~kB
this.totalPage = totalPage; TJS1,3<
this.currentPage = currentPage; kTc5KHJ7
this.beginIndex = beginIndex; F{~r7y;0
} @ ]wem
ULmdt
/** {0WIDD
* @return 4Xk;Qd
* Returns the beginIndex. F6]!?@
*/ oHd0
<TO
publicint getBeginIndex(){ +gCy@_2;
return beginIndex; P Xn>x8z
} 1'm`SRX#e
{<4?o?
1g
/** 6@;L$QYY-V
* @param beginIndex _|wY[YJ[
* The beginIndex to set. x~Ly$A2p
*/ 4eL54).1O
publicvoid setBeginIndex(int beginIndex){ 1"B9Z6jf
this.beginIndex = beginIndex; @ZR4%A"X4
} UH&1c8y}
,xe@G)a
/** %aE7id>v6
* @return (`.qG
&6p
* Returns the currentPage. G:C6`uiy`
*/ 8kM0
publicint getCurrentPage(){ <ZC^H
return currentPage; '#
IuY
} ! vVjZ
p2DNbY\]
/** as|c`4r\O
* @param currentPage Y1aF._Z
* The currentPage to set. `=$jc4@J
*/ Z6([/n
publicvoid setCurrentPage(int currentPage){ wp*&&0O!
this.currentPage = currentPage; 9iddanQA
} +\[![r^P
V -4*nV
/** pMZf!&tM
* @return $F`<&o
* Returns the everyPage. )bXx9,VL
*/ akc"}+-oX
publicint getEveryPage(){ h)l&K%4;
return everyPage; 1o~U+s_r
} YEPG[W<kg
|U$de2LF
/** ecqz@*d&
* @param everyPage HZ<f(
* The everyPage to set. ~muIi#4
*/ g6/N\[b%
publicvoid setEveryPage(int everyPage){ vWi.[]
this.everyPage = everyPage; Z0 IxYEp
} vV\F^
-,fa{ yt-
/** a.dxgW[
* @return $ X=D9h
* Returns the hasNextPage. ctUF/[_w;
*/ g=g.GpFt
publicboolean getHasNextPage(){ +V+*7s%fL
return hasNextPage; r~G]2*3
} h[ZN >T
A;WwS?fyQ
/** [T[9*6Kt
* @param hasNextPage p1VahjRE-
* The hasNextPage to set. 1s}NQ3
*/ CX ]\Q-y
publicvoid setHasNextPage(boolean hasNextPage){
2HK
this.hasNextPage = hasNextPage; kGuk
-P
} $sL|'ZMbS
q>|[JJ*6_N
/** ZH$sMh<xg
* @return #C,f/PXfaB
* Returns the hasPrePage. @U
/3iDB\
*/ 3+8"
publicboolean getHasPrePage(){ ,+f0cv4
return hasPrePage; m~j\?mb{+
} ~Riu*<
01{r^ZT`RH
/** R|)2Dg
* @param hasPrePage |N=@E,33
* The hasPrePage to set. [
4Y
`O
*/ `k}l$ih`X
publicvoid setHasPrePage(boolean hasPrePage){ ,8xP8T~Kmv
this.hasPrePage = hasPrePage;
kF+ }.x%
} BvZ^^IUb
<`p75B
/** APtselC
* @return Returns the totalPage. 7tfivIj)e
* ueE?"Hk
*/ 4/`h@]8P
publicint getTotalPage(){ Y7:Y{7E7
return totalPage; 9"HmHy&:E
} \Ul.K!b7
>\?z37:T
/** g",w kO|
* @param totalPage SA(U D
* The totalPage to set. i#]aV]IT
*/ 1t\b a1x
publicvoid setTotalPage(int totalPage){ Z4HA94
this.totalPage = totalPage; D-o7yc"K
} b,rH&+2H
2i7i\?<.
} $['7vcB^
Tn@UX(^,
}ED
nLou
Yt/SnF
,\S pjE
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 0 .FHdJ<
1~R$$P11[9
个PageUtil,负责对Page对象进行构造: W3jXZ>
java代码: ie$`pyj!x
G+hF
[b44'
c>R`jb@$N
/*Created on 2005-4-14*/ 4{*tn"y
package org.flyware.util.page; "^9[OgE:
mZbWRqP[|_
import org.apache.commons.logging.Log; cZDxsd]
import org.apache.commons.logging.LogFactory; $c@w$2
j Ne(w<',P
/** wUK7um
* @author Joa o9m
* "+n4 c'
*/ _}I(U?Q-C
publicclass PageUtil { H:q )^$s
jF38kj3O7
privatestaticfinal Log logger = LogFactory.getLog FpdDIa
]3O
4\o
(PageUtil.class); Wa[x`:cT?u
VDByj "%
/** atLV`U&t
* Use the origin page to create a new page uq !;
* @param page <$i"zb
* @param totalRecords cS D._"P
* @return ocIt@#20K
*/ #cj\~T.,,
publicstatic Page createPage(Page page, int i<4>\nc
pKt-R07*
totalRecords){ )YzH k ;(
return createPage(page.getEveryPage(), XMN?;Hj>
6o=qJ`m[?
page.getCurrentPage(), totalRecords); xH_A@hf;
} Lh8bQH
=zeFK_S!
/** ]UX`=+{
* the basic page utils not including exception 5q|+p?C
5:Yck<
handler c Ndw9?Z
* @param everyPage .7
(DxN
* @param currentPage V&Xi> X8
* @param totalRecords y4xT:G/M
* @return page E /fw?7eQ
*/ 4GG1E. z}
publicstatic Page createPage(int everyPage, int SXRdNPXFO
<91t`&aWW
currentPage, int totalRecords){ 1Yc%0L(
everyPage = getEveryPage(everyPage); H+4=|mkQ
currentPage = getCurrentPage(currentPage); {8^Gs^c
c
int beginIndex = getBeginIndex(everyPage, `6a]|7|f
lpl8h4d
currentPage); v!NB~"LQ
int totalPage = getTotalPage(everyPage, uP{;*E3?
X}oj_zsy;^
totalRecords); rQ9*J
boolean hasNextPage = hasNextPage(currentPage, )!'n&UxPo$
)\{'fF
totalPage); IK*oFo{C=K
boolean hasPrePage = hasPrePage(currentPage); Y%<`;wK=^
\*f;!{P{
returnnew Page(hasPrePage, hasNextPage, az0cS*@
everyPage, totalPage, Vh"MKJ'R^
currentPage, <,jAk4
<Ctyht0c.
beginIndex); ,f}h}
} H4M{_2DO
NH'1rt(w
privatestaticint getEveryPage(int everyPage){ Eo%UuSi
return everyPage == 0 ? 10 : everyPage; +yzcx3<
} Tr}R`6d$
MKU7fFN.
privatestaticint getCurrentPage(int currentPage){ u-m %=2
return currentPage == 0 ? 1 : currentPage; Q`H#
fS~
} '5'3_vM
No:^hY:F8
privatestaticint getBeginIndex(int everyPage, int 3c c1EQ9
f?,-j>[.=f
currentPage){ y L*LJ
return(currentPage - 1) * everyPage; \r)%R5_CQ
} {IJ-4>
C&=x3Cz
privatestaticint getTotalPage(int everyPage, int BjM+0[HC
}o-|8P:Y
totalRecords){ `vudS?
int totalPage = 0; ; ;<J
x.
t,RyeS/
if(totalRecords % everyPage == 0) sz'p3
totalPage = totalRecords / everyPage; |<sf:#YzY&
else cp$.,V
totalPage = totalRecords / everyPage + 1 ; :@.C4oq
:~yzDk\I"-
return totalPage; CE)*qFs
} :`D'jF^S
QQ@9_[N
privatestaticboolean hasPrePage(int currentPage){ *5e<\{!
return currentPage == 1 ? false : true; }04Dg'
} S|HY+Z6n'
Ba<ngG
!
privatestaticboolean hasNextPage(int currentPage, SU/G)&Mi
Q~phGD3!~
int totalPage){ ]bIt@GB
return currentPage == totalPage || totalPage == brntE:
UmJUt|
0 ? false : true; Zp`~}LV{
} V|TA:&:7
bZiyapM
QV0M/k<'
} @|Dm E!)
pjACFVMFX
zt?h^zf}
0A.PD rM:
2xDQ:=ec
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 J==}QEhQ{
?FN9rhAC
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 j~epbl)pC
B22b&0
做法如下: [ a@B
=E
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ' PELf
P8
>)LAjwhBp
的信息,和一个结果集List: u*hH}
java代码: >rKhlUD
zhX;6= X2
7{-@}j`
/*Created on 2005-6-13*/ W,Ty=:qm*
package com.adt.bo; _
\l
HI
K5{{:NR$
import java.util.List; QP:9%f>=
.:8[wI_f
import org.flyware.util.page.Page; mH)OB?+lq
hcyn
/** }wfI4?}j}
* @author Joa ^p,3)$
*/ 2 l(Dee Y
publicclass Result { ? ~,JY
gwiR/(1
private Page page; Tv\HAK<N
~
7}]
private List content; /_q#ah
M|k&TTV
/**
vO]J]][
* The default constructor '*4iqPR;
*/ ,ijW(95{k
public Result(){ )A"jVQjI%w
super(); PK+ x6]x
} &U&Zo@ot"x
uN9e:;
/** ailG./I+
* The constructor using fields +#~O'r]%GG
* j{)~QD ?
* @param page jB!W2~Z
* @param content Y''6NGf
*/ eQ<xp A
public Result(Page page, List content){ OF8WDo`
this.page = page; 12lEs3
this.content = content; 4:U0f;Fs
} dKm`14f]@G
Jn*Nao_)
/** 9:-T@u
* @return Returns the content. 0R|K0XH#$
*/ Rboof`pVt
publicList getContent(){ $T),DUYO
return content; p.C1 nh
} #EG?9T
1i3V!!r
/** &hI>L
* @return Returns the page. 333u]
*/
%}h`+L
public Page getPage(){
4{Udz!
return page; 9 #Y2`pT
} zmb@*/fK
p![&8i@ym
/** J)*8|E9P
* @param content s`c?:
* The content to set. j=W@P-
*/ Vv7PCaq
public void setContent(List content){ Xhse~=qA
this.content = content; P>wZ~Hjk
} #h N.=~
2:'lZQ
/** BC({ EE~R)
* @param page DWrbp
* The page to set. g/#~N~&
*/ YBvd
q1
publicvoid setPage(Page page){ o@3B(j;J`
this.page = page; /UHp [yod
} vLDi ;
} )b92yP{
EeB3 }
$)*xC!@6X
TEWAZVE*
Pbe7SRdr^
2. 编写业务逻辑接口,并实现它(UserManager, <tuS,.
Dx3 %KS
UserManagerImpl) {y6C0A*
java代码: 5
`=KyHi:b
H)5QqZ8
F\LsI;G
/*Created on 2005-7-15*/ TatMf;?h&
package com.adt.service; KO&:06V{
l.oBcg[
import net.sf.hibernate.HibernateException; 7/"@yVBW
6m[9b*s7
import org.flyware.util.page.Page; oLS7`+b$
a#y{pT2 b
import com.adt.bo.Result; dB3N%pB^
%S`ik!K"I
/** ~ziexZ=N
* @author Joa E>}q2
*/ S+ebO/$>
publicinterface UserManager { b_vTGl1_6
4SR(->@
public Result listUser(Page page)throws g1@wf
bS rZ{l
HibernateException; k[9A,N^lZB
x=Mm6}/
} s;1e0n
z0Xa_w=
m*oc)x7'
rzu
s
tpYa?ZCM
java代码: eYEc^nC,c)
Hk u=pr3Gn
4RQ5(YTTuR
/*Created on 2005-7-15*/ /{X_
.fv<v
package com.adt.service.impl; ]:et~pfW
k1fRj_@WPT
import java.util.List; w>vH8f
:JlDi>B
import net.sf.hibernate.HibernateException; D|Si)_
Iz
4j3oT)+8
import org.flyware.util.page.Page; x=,8[W#XT
import org.flyware.util.page.PageUtil; GN%(9N'W
_7@z_i_c
import com.adt.bo.Result; ^i`*Wm@!
import com.adt.dao.UserDAO; l>7r2;
import com.adt.exception.ObjectNotFoundException; J]fS({(\I
import com.adt.service.UserManager; |zpx)8Q
?@UAL.y
/** GMm'of#
* @author Joa A5XR3$5P
*/ r1Z<:}ZwK
publicclass UserManagerImpl implements UserManager { r)b<{u=]
{?i)K X^
private UserDAO userDAO; a)S7}0|R
C) .2gQ
G
/** ce' TYkPM
* @param userDAO The userDAO to set. Km*<Kfcz
*/ lIh[|]
publicvoid setUserDAO(UserDAO userDAO){ ]yLhJ_^
this.userDAO = userDAO; 9=$!gC)
} bk3Unreh
kG^dqqn6
/* (non-Javadoc) 'msmXX@q
* @see com.adt.service.UserManager#listUser >IY,be6>P
yr{B5z,
(org.flyware.util.page.Page) 2OalAY6RS
*/ J#7y<
s
public Result listUser(Page page)throws @!\K>G >9[
]a/'6GbR
HibernateException, ObjectNotFoundException { GZ8:e3ri
int totalRecords = userDAO.getUserCount(); I7mG/
if(totalRecords == 0) <zfKC
throw new ObjectNotFoundException F_ljx
(M`|'o!
("userNotExist"); *IZf^-=Q
page = PageUtil.createPage(page, totalRecords); HarFE4V
List users = userDAO.getUserByPage(page); R0<< f]
returnnew Result(page, users); U:|H9+5
} J&6:d
Gzm$OHbn
} s;{K!L@
ez*jjm
M !{'ED
jTSOnF}C~+
l2&hBacT
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Uix{"
qI2'u %
询,接下来编写UserDAO的代码: "l,UOv c
3. UserDAO 和 UserDAOImpl: }.{}A(^YR
java代码: 9;KJr[FQV
j|K.i/
&U&%ka<*
/*Created on 2005-7-15*/ Coa -8j*R7
package com.adt.dao; @J vZ[T/
&1Fply7(Ay
import java.util.List; ZnXejpj)D
hz)9"B\S
import org.flyware.util.page.Page; f\K#>u*
Q
\0AiCMX[
import net.sf.hibernate.HibernateException; n`L,]dco
h0VzIuV
/** nGrVw&
* @author Joa ;nB2o-%
*/ 3s(Ia^
publicinterface UserDAO extends BaseDAO { ("Dv>&w9
ZBc|438[
publicList getUserByName(String name)throws 8D~x\!(p\
]k+m=OR{/
HibernateException; _;e\:7<m
Q$=*aUU%G
publicint getUserCount()throws HibernateException; }<[Db}?9
O9]\Q@M.
publicList getUserByPage(Page page)throws LSkk;)'2K
yFM>T\@
HibernateException; i_U}{|j
dZ2`{@AYY
} 9P"iuU
Oif,|:
Vxh.<b6&'
:oa9#c`L
Y<LNQ]8\G
java代码: N z~"vi(t
AcC8)xRpk4
/f3m)pT
/*Created on 2005-7-15*/ #`/QOTnm2c
package com.adt.dao.impl; @ {}rG8
3jPB#%F
import java.util.List; X?dfcS*!n
|}S1o0v{(a
import org.flyware.util.page.Page; R^8B3-aA`
^
KH>1!
import net.sf.hibernate.HibernateException; crn k|o
import net.sf.hibernate.Query; CLK^ gZ
[7\>"v6
import com.adt.dao.UserDAO; e4.&aIC[
}uQ${]&D
/** ,w`~K:b.
* @author Joa CC8k&u,
*/ aRwnRii
public class UserDAOImpl extends BaseDAOHibernateImpl {Y_Nj`#BT
(9GbG"
implements UserDAO { h>3H7n.
Hed$ytMaGz
/* (non-Javadoc) ;<-7*}Dj
* @see com.adt.dao.UserDAO#getUserByName rn" pKUd
\P?A7vuhLs
(java.lang.String) K]"Kf{bx
*/ Tf-CEHWD
publicList getUserByName(String name)throws uec|S\~M
}lfn0 %(@
HibernateException { ~A >oO-0K
String querySentence = "FROM user in class )H+kB<n
dAxp ,):&J
com.adt.po.User WHERE user.name=:name"; XxOn3i
Query query = getSession().createQuery %f!iHo+Z
7~vqf3ON4J
(querySentence); ] !Zty[
query.setParameter("name", name); f\}22}/
return query.list(); )%mAZk-*;^
} 3{3/: 7
`clB43i
/* (non-Javadoc) .~`Y)PON
* @see com.adt.dao.UserDAO#getUserCount() pP\h6b+B
*/ knSuzq%*
publicint getUserCount()throws HibernateException { =kFuJ
x)f
int count = 0; _T]>/}}p
String querySentence = "SELECT count(*) FROM V/bH^@,sA
~`Sle
xK|}
user in class com.adt.po.User"; [ud|dwP"
Query query = getSession().createQuery .,mPdVof
(hf zM+2
(querySentence); ']?=[`#NL
count = ((Integer)query.iterate().next Y6VQ:glDT-
J
Jy{@[m
()).intValue(); p\S8oHWe
return count; r~oSP^e'
} ct0v$ct>f
f z%tA39m
/* (non-Javadoc) KXe
ka
* @see com.adt.dao.UserDAO#getUserByPage ( V4G<-jG
O5-;I,)H
(org.flyware.util.page.Page) x!?Z*v@I
*/ M 9"-WIG@h
publicList getUserByPage(Page page)throws 2Xgx*'t\
H#+xKYrp
HibernateException { <SQ(~xYi
String querySentence = "FROM user in class QS\
x{<e/
}m_t$aaUc1
com.adt.po.User"; @^CG[:|
Query query = getSession().createQuery {!=2<-Aq
;3UvkN
(querySentence); uaxB -PZ
query.setFirstResult(page.getBeginIndex()) :qnokrGzB
.setMaxResults(page.getEveryPage()); 1nB@zBQu-
return query.list(); sqG`"O4W
} xF8 :^'
DHzkRCM
} 7;xKy'B\
q\H7&w
JZ K7uB,X
xG%*PNM0q
F+*Q <a4
至此,一个完整的分页程序完成。前台的只需要调用 %6 ]\^
1Z:R,\+L
userManager.listUser(page)即可得到一个Page对象和结果集对象 +/q0Y`v
yW>R RE;
的综合体,而传入的参数page对象则可以由前台传入,如果用 J3&Sj{ o
.)`-Hkxa
webwork,甚至可以直接在配置文件中指定。 F< |c4
*?N<S$m
下面给出一个webwork调用示例: <E}N=J'uJ
java代码: }+DDJ6Jzs
C1 {ZW~"YI
xid:" y=_&
/*Created on 2005-6-17*/ \7
Mq $d
package com.adt.action.user; <gcmsiB|
o)!m$Q~v
import java.util.List; #=x+
[d+
& rQD `E/
import org.apache.commons.logging.Log;
UTX](:TC
import org.apache.commons.logging.LogFactory; wlVvxX3%
import org.flyware.util.page.Page; BWEv1' v
.. UoyBV
import com.adt.bo.Result; <[9?Rj@
import com.adt.service.UserService; (nz}J)T&
import com.opensymphony.xwork.Action; :c<*%*e
SG`)PW?
/** ~04[KG
* @author Joa )*
3bkKVB
*/ ,s? dAy5
publicclass ListUser implementsAction{ Ff)@L-Y\K
ITc`]K
privatestaticfinal Log logger = LogFactory.getLog 8[HZ@@
NL-_#N$
(ListUser.class); R&!]Rl9hf
+-P<CCvWz
private UserService userService; -fPT}v
pK"&QPv
private Page page; D1ZC&B_}-
/.v_N%*-v
privateList users; X<FOn7qf
%,;gP.dh7
/* %/%gMRXG2
* (non-Javadoc) ^S=cNSpC
* ~oFh>9u
* @see com.opensymphony.xwork.Action#execute() eP?~-#
*/ %`oHemSy
publicString execute()throwsException{ 0BDoBR
Result result = userService.listUser(page); cz>mhD
page = result.getPage(); xp=Zd\5W$
users = result.getContent(); -3 ]|[
return SUCCESS; 9m~t
j_
} w&C1=v -h
#%WCL'6B
/** [D hEh@
* @return Returns the page. mR,O0O}&
*/ ]|y}\7Aa
public Page getPage(){ k-vA#
return page; B{99gwMe]
} 6Ty3e|do
-xTKdm
D
/** CPGL!:
* @return Returns the users. Z+,CL/
*/ gi 5XP]z
publicList getUsers(){ g@(4ujOT
return users; ZR6&AiL(Bj
} %HVD^. V
&L'6KEahR
/** VH<e))5C
* @param page nUqL\(UuY
* The page to set. ]7l{g9?ZtV
*/ (QKsB3X
publicvoid setPage(Page page){ SlN" (nq
this.page = page; ,@479ZvvR3
} T,Fm"U6[(
`OBl:e
/** g+3Hwtl
* @param users |C4o zl=O?
* The users to set. Fq4lXlSB
*/ [brkx3h
publicvoid setUsers(List users){ UT~4Cfb
this.users = users; `xGT_0&ck
} @Rf^P(
tbS#^Y
/** nAvs~J
* @param userService Cg7)S[zl
* The userService to set. c~37+^B:
*/ B/rzh? b
publicvoid setUserService(UserService userService){ N:7.:Yw
this.userService = userService; [lZ=s[n.
} S,VyUe4P4
} YLE/w @*
IOS^|2:,
G-ZhGbAI7
N-xnenci
eZA6D\
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, m'c#uU
d#4 Wj0x
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 L@+Z)# V
moe/cO5a9
么只需要: VH[l\I(h
java代码: ys/vI/e\
=CE HRny
JC/d:.
<?xml version="1.0"?> i!tc
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork y{?Kao7Ij
N?zV*ngBS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- @??u})^EL
Z|}H^0~7S
1.0.dtd"> $8=(I2&TW
my]P_mE
<xwork> hj+p`e S
q{[1fE"[K4
<package name="user" extends="webwork- wzg i
@i
K` 2i
interceptors"> ps"9;4P
Vl-D<M+ih
<!-- The default interceptor stack name ;tm3B2
zWJKYF qK
--> ZrA
Um
<default-interceptor-ref 8z?$t-D O
mcCB7<.
e
name="myDefaultWebStack"/> w gmWo8
yX`J7O{=
<action name="listUser" eXc[3ceUr
4I
z.fAw
class="com.adt.action.user.ListUser"> f^~2^p
1te
<param 3|jn,?K)N
s
*K:IgJ/
name="page.everyPage">10</param> MV9r5 |3-
<result t6j-?c('
` 4OMZMq
name="success">/user/user_list.jsp</result> p0
</action> \;iG{}(
KLON;
</package> Z`|> tbOfZ
2UQN*_
</xwork> ,=yOek}
O0->sR
"--/v. Cs
d4Ixuux<3
S io1Q0
ykJ+%gla
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 zI(xSX@
g^qz&;R]
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。 .iN-4"_j1
vs*>onCf
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 r}Ltv?4
nMLU-C!t
Sb^a dd0dT
{npOlV
\MF3CK@/
我写的一个用于分页的类,用了泛型了,hoho JATS6-Lz`
.V7Y2!4TE
java代码: <1TlW
~q<
!,I7 ?O
ZBPd(;"x+
package com.intokr.util; LAj}kW~
jQO*oq}
import java.util.List; '9f6ZAnYpQ
7sCR!0
/** E*Pz <
* 用于分页的类<br> | pF5`dX
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 7k.d|<mRv
* ]6jHIk|
* @version 0.01 /j`i/Ha1
* @author cheng Og_2k
~
*/ f34_?F<h
public class Paginator<E> { 6s> sj7
privateint count = 0; // 总记录数 ~ W2:NQ>i
privateint p = 1; // 页编号 9yO{JgKA
privateint num = 20; // 每页的记录数 qn5yD!1
privateList<E> results = null; // 结果 `\Uc4lRS
Iq^~
/** c(QG4.)m
* 结果总数 ?ykVf O'
*/ #(m`2Z`H
publicint getCount(){ [lmHXf@1C
return count; PWADbu{+
} ^vYVl{$bT
3WQRN_
publicvoid setCount(int count){ w:~nw;.T
this.count = count; 6 Xzk;p
} xC=
y^-
1
Y{+zg9L*
/** 7qCJ]%)b6
* 本结果所在的页码,从1开始 !#}v:~[A
* AsTMY02|
* @return Returns the pageNo. aeN}hG
*/ 9:bh3@r/
publicint getP(){ nF|#@O`1
return p; #j(q/
T{x
} tI/mE[W
x.j Yip
/** K0d-MC
* if(p<=0) p=1 9^6|ta0;0
* GN"M:L^k`
* @param p 6ON
*/ Z"teZ0H
publicvoid setP(int p){ o[5=S,'
if(p <= 0) ;t.SiA
p = 1; L7~+x^kw
this.p = p; !=8L.^5c
} V+4k!
}qgqb
/** d
A_S"Zc
* 每页记录数量 eO|^Lu]+
*/ jhjW*F<u
publicint getNum(){ ]# tGT0
return num; $Uv<LVd(
} ]be0I)
gJ)h9e*m^
/** 4~]8N@Bii
* if(num<1) num=1 $@+p~ )r(l
*/ >Hd~Ca>
publicvoid setNum(int num){ |r)>bY7
if(num < 1) #+2:d?t
num = 1; [[Jv)?jm
this.num = num; UUdu;3E=5
} $sd3h\P&R
];d5X
/** i_oro"%yL
* 获得总页数 ;-Y]X(z>
*/ lOowMlf@2
publicint getPageNum(){ W TXD4}
return(count - 1) / num + 1; ZNL;8sI?>
} *@$($<pY&
#z-iL!?
/** r{Qs9
* 获得本页的开始编号,为 (p-1)*num+1 } kh/mq
*/ +O.&64(
publicint getStart(){ S*2L4Uj`|
return(p - 1) * num + 1; 9TbS>o
} :FKYYH\
thlpj*|
/** teQaHe#
* @return Returns the results. ~P"!DaAf
*/ B BApL{
publicList<E> getResults(){ hy!'Q>[`
return results; =
C$@DNEc
} ,oB k>
110>p
public void setResults(List<E> results){ ~vjr;a(B
this.results = results; .yFg$|y G
} aOAwezfYR
5CRc]Q#@
public String toString(){ fY,@2VxyfA
StringBuilder buff = new StringBuilder Xn
ZX *Y]"
7(+OsE
(); e GqvnNv
buff.append("{"); }]n>A
buff.append("count:").append(count); -Fok%iQ'5
buff.append(",p:").append(p); ,
$D&WH
buff.append(",nump:").append(num); BRSgB-Rr7
buff.append(",results:").append :#Ex3H7
Nw3I
(results); 3 -_U-:2"
buff.append("}"); H8o%H=I%
return buff.toString(); ,XBV }y
} Nak'g/uP>
<De3mZb
} +qSr=Y:+
*k@0:a(>
&)"7am(S`