Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +lcbi
Ie#Bkw'*
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 G<J?"oQbRT
p6Gy,C.
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 J<h$
wM
rw JIx|(
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 mNTzUoZF'@
$G@5qxcV
。 N5
6g+,w%)
ul >3B4
分页支持类: }9OC,Y8?D
n 0L^e
java代码: WP'!*[z
'_FsvHQ
E]-/Zbvdv
package com.javaeye.common.util; jm/`iXnMf
[hv~o~q
import java.util.List; "]Xc`3SM
h3
}OX{k
publicclass PaginationSupport { VjZ|$k
4vB<fPN
publicfinalstaticint PAGESIZE = 30; Eo]xNn/g
( ^Nz9{
privateint pageSize = PAGESIZE; VuZuS6~#J
y766;
X:J
privateList items; S;#'M![8
uz
jU2
privateint totalCount; 'I6i,+D/q
s9DYi~/,
privateint[] indexes = newint[0]; j'"J%e]
$B5aje}i
privateint startIndex = 0; }00BllJ
; )@~
public PaginationSupport(List items, int I:1C8*/
.|i.Cq8
totalCount){ [5Mr@f4I
setPageSize(PAGESIZE); Q sCheHP
setTotalCount(totalCount); ^o&. fQ*
setItems(items); x7<K<k;s
setStartIndex(0); K`fuf=
} 60?%<oJ oH
'!~)?C<
public PaginationSupport(List items, int i5@z< \
'3^'B03
totalCount, int startIndex){ |#R7wnE[k~
setPageSize(PAGESIZE); ^>v+(
z5R
setTotalCount(totalCount); 1f=gYzuO)
setItems(items); pG;U2wE
setStartIndex(startIndex); w@w(-F!%l
} 7a<DKB
4zFW-yy
public PaginationSupport(List items, int e^1Twz3z
,/|T-Ka
totalCount, int pageSize, int startIndex){ A#YrWW
setPageSize(pageSize); Vp@?^imL
setTotalCount(totalCount); A_q3KB!$=+
setItems(items); 1\I}2;
setStartIndex(startIndex); oj+hQ+>
} NyNXP_8
NU2;X (z[
publicList getItems(){ tf`^v6m%]
return items; L$M9w
} ?hy&
*VxgARIL
publicvoid setItems(List items){ /jJw0 5;L
this.items = items; M[,@{u/
} fVpMx4&F
:,6\"y-
publicint getPageSize(){ uJ v-4H
return pageSize; a<bwzX|.
} \z(gqkc 6
*u;Iw{.{
publicvoid setPageSize(int pageSize){ VRB;$
this.pageSize = pageSize; pIqeXY
} Q*~]h;6\{d
ye5&)d"fa(
publicint getTotalCount(){ ^^D0^k!R
return totalCount; 7WZ+T"O{I
} Qq|57X)P*
Lt>IX")
publicvoid setTotalCount(int totalCount){ 2g! +<YZ~
if(totalCount > 0){ aAUvlb
this.totalCount = totalCount; DEZveQr=
int count = totalCount / QhJiB%M
>pe.oxY
pageSize; o!A+&{
if(totalCount % pageSize > 0) cSV aI
count++; SO0PF|{\r
indexes = newint[count]; #S"nF@
for(int i = 0; i < count; i++){ 7zG_(83)K
indexes = pageSize * Uz]|N6`
#KZBsa@p
i; 11;MN
} dvUic-w<j
}else{ ~b8]H|<'Y
this.totalCount = 0; *0=j?~&
} ?&1!vz
} KPUV@eQ,
qlPT Ll
publicint[] getIndexes(){ Z(CkZll
return indexes; nAdf=D'P
} Mb*?5R6;
7-fb.V9
publicvoid setIndexes(int[] indexes){ z~s PXGb
this.indexes = indexes; 2<}%kQ`
} *\F~[
C$`tbq
publicint getStartIndex(){ "3Y0`&:D
return startIndex; QoT;WM Z
} x7 ,5
}Jj}%XxKs
publicvoid setStartIndex(int startIndex){ @f3E`8
if(totalCount <= 0) 63IM]J
this.startIndex = 0; R.<g3"Lm>
elseif(startIndex >= totalCount) .8JTe0
this.startIndex = indexes Ml-6OvQ7g
DZtsy!xA
[indexes.length - 1]; H0vfUF53l
elseif(startIndex < 0) \:LW(&[!
this.startIndex = 0; )zDCu`
else{ Nu)NqFG,
this.startIndex = indexes dioGAai'
mj7#&r,1l
[startIndex / pageSize]; 19%imf
} E|shs=I
} *.w9c
j8:\%|
publicint getNextIndex(){ 44j*KsBf
int nextIndex = getStartIndex() + <t!W5q
b^vQpiz
pageSize; {Ou1KDy#)
if(nextIndex >= totalCount) ~WF\
return getStartIndex(); Y"$xX8o
else @d1Q"9}B
return nextIndex; WcbiqxK7-
} !ULn7\@
l,aay-E
publicint getPreviousIndex(){ R`-S/C
int previousIndex = getStartIndex() - $M:*T.3
gf\oC> N
pageSize;
|-~Y#]
if(previousIndex < 0) _Y m2/3!
return0; )%fH(ns(
else 0#gK6o!
return previousIndex; ;5( UzQU
} lPAQ3t!,
_+3::j~;m
} cPQiUU~W@
$3kH~3{]
ba9?(+i$h
*/S_Icf
抽象业务类 wVtwx0|1
java代码: lH~[f
d2L&Z_}
uCB=u[]y4
/** ql~J8G9
* Created on 2005-7-12 b%c9oR's^
*/ f*
wx<
package com.javaeye.common.business; :[d9tm
u)Whr@m
import java.io.Serializable; _,*r_D61S
import java.util.List; jSaU?ac
uhq8
import org.hibernate.Criteria; M )(DZ}
import org.hibernate.HibernateException; h;'~,xA
import org.hibernate.Session; 0<*<$U
import org.hibernate.criterion.DetachedCriteria; tX~w{|k
import org.hibernate.criterion.Projections; V|R,!UND
import b7ZSPXV
-D:b*D
org.springframework.orm.hibernate3.HibernateCallback; pQQH)`J|t
import JlJ a
#
#lO Mm9
org.springframework.orm.hibernate3.support.HibernateDaoS >8[Z.fX
zKK9r~ M
upport;
Wa~=bH
^=*;X;7
import com.javaeye.common.util.PaginationSupport; l}P=/#</T
s,_m{ to
public abstract class AbstractManager extends 8xMX
wdoR%b{M
HibernateDaoSupport { f?)-}\[IR{
c[s4EUG
privateboolean cacheQueries = false; G KeU%x
A?0Nm{O;3v
privateString queryCacheRegion; -ze J#B)C
CNx8]
_2
publicvoid setCacheQueries(boolean Kf-JcBsrT
c4z R*
cacheQueries){ .eC1qWZJpd
this.cacheQueries = cacheQueries; YHl;flv
} [KQ6Ta.
. 'yCw#f
publicvoid setQueryCacheRegion(String IUct
OB}Ib]
queryCacheRegion){ o<!?7g{
this.queryCacheRegion = -%4,@
x`
.tr!(O],h
queryCacheRegion; <\S:'g"(
} lUMdrt0@z
CTA3*Gn
publicvoid save(finalObject entity){ uvS)8-o&F
getHibernateTemplate().save(entity); e8b:)"R
} a-J.B.A$Z/
>`D:-huNeE
publicvoid persist(finalObject entity){ |vzl. ^"-
getHibernateTemplate().save(entity); L{Vqh0QD&
} Jfl!#UAD|n
rQ snhv
publicvoid update(finalObject entity){ f`66h M[
getHibernateTemplate().update(entity); .5{ab\_af
} 9-m=*|p
,"79P/C
publicvoid delete(finalObject entity){ h!9ei6
getHibernateTemplate().delete(entity); _GPl gp:
} 5Jnlz@P9
f6"Z'{j
publicObject load(finalClass entity, }SCM I4\
q-d:TMkc
finalSerializable id){ Fv`,3aNB
return getHibernateTemplate().load LjHVJSC
UJ6v(:z<
(entity, id); ?!/kZM_ts
} &PtJ$0%q
~4cC/"q$X
publicObject get(finalClass entity, S:ztXhif>
+X]vl=0
finalSerializable id){ K\c#ig
return getHibernateTemplate().get iO;
7t@]-
8DaL,bi*.
(entity, id); aC)!T
} x]ot 2
^pk7"l4Xm
publicList findAll(finalClass entity){ ,
++ `=o
return getHibernateTemplate().find("from j"Pv0tehw
uY'HT|@:{
" + entity.getName()); y:l\$pGC%
} Pk)1WK7E
jWfa;&Ra
publicList findByNamedQuery(finalString
J5jvouR
,s;UfF
namedQuery){ E-g_".agO
return getHibernateTemplate JqiP>4Uwm^
VyGJ=[ ]
().findByNamedQuery(namedQuery); }RqK84K
} 8)I^ t81
5/Uy{Xt
publicList findByNamedQuery(finalString query, /&94 eC
IPo?:1x]s
finalObject parameter){ b;UJ 88
return getHibernateTemplate AYx{U?0p
VP]% Hni]
().findByNamedQuery(query, parameter); HyWCMK6b
} u;c?d!E
um0N)&iY
publicList findByNamedQuery(finalString query, |$b}L7_
c!9nnTap
finalObject[] parameters){ +srGN5!
return getHibernateTemplate o"#\
>
JaGtsi9%.
().findByNamedQuery(query, parameters); vRO
_Q?
} n.(FQx.F
%bfQ$a:
publicList find(finalString query){ E^eVvP4uC@
return getHibernateTemplate().find Dm<A
^u8
kPLxEwl
(query); E~oOKQ5W
} p.?rey<%
emN*l]N
publicList find(finalString query, finalObject JFk
lUgg
[HZv8HU|
parameter){ L/G6Fjg^
return getHibernateTemplate().find }U"&8%PZr
N//KPh
(query, parameter); %8~NqS|=
} YcpoL@ab
jtc]>]6i
public PaginationSupport findPageByCriteria I9hK }D
hZ
(final DetachedCriteria detachedCriteria){ D!IY&H,wo
return findPageByCriteria wDe& 1(T^
~FG]wNgS
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ut7zVp<"
} W|63Ir67
YteO6A;
public PaginationSupport findPageByCriteria Z}Ft:7
%Y*Ndt 4
(final DetachedCriteria detachedCriteria, finalint &FN.:_E
-C?ZB}`
startIndex){ ( 0_2sfS
return findPageByCriteria xYpd: Sm
*YuF0Yt
(detachedCriteria, PaginationSupport.PAGESIZE, l]l'4@1
.5ha}=z
startIndex); q'Tf,a
} vT,AMja
6gu!bu`~
public PaginationSupport findPageByCriteria lp%pbx43s
);&:9[b_
(final DetachedCriteria detachedCriteria, finalint Vb]=B~ ^`
mSl.mi(JiZ
pageSize, [j/9neaye
finalint startIndex){ Q:d]imw!O
return(PaginationSupport) ,M
^<CJ
p]2128kqx
getHibernateTemplate().execute(new HibernateCallback(){ ]Ntmy;Q
publicObject doInHibernate jLHkOk5{:
)W
_v:?A9
(Session session)throws HibernateException { ^ Q ?
Criteria criteria = nazZ*lC
PmEsN&YP]
detachedCriteria.getExecutableCriteria(session); <FkFs{(t
int totalCount = N]=q|D
gu.}M:u
((Integer) criteria.setProjection(Projections.rowCount $1L>)S
!Pfr,a
()).uniqueResult()).intValue(); x@;m8z0
criteria.setProjection wIaony
,G?WAOy,
(null); i#Bf"W{F
List items = r1{@Ucw2
~H<6gN<j(.
criteria.setFirstResult(startIndex).setMaxResults Gk&)08
#rQ2gx4
(pageSize).list(); !")tU+:
PaginationSupport ps = l'E*=Rn
:vQrOn18p
new PaginationSupport(items, totalCount, pageSize, Q6!zZ))~
,~@X{7U
startIndex); A>;bHf@
return ps; k1Y ?
} #:U%mHT(_
}, true); Y0dEH^I
} Y>dzR)~3[
'9Xu
p
public List findAllByCriteria(final XZ]uUP
@&3EJ1
DetachedCriteria detachedCriteria){ SaAFz&WRl
return(List) getHibernateTemplate }9# r0Vja
_Gi4A
().execute(new HibernateCallback(){ *:LK8U
publicObject doInHibernate DIfaVo/"
U!?_W=?
(Session session)throws HibernateException { ;dtA4:IRZ4
Criteria criteria = p\tm:QWD;
*-=(Q`3
detachedCriteria.getExecutableCriteria(session); (Ag16
return criteria.list(); D4lG[qb
} 17[3/m8a
}, true);
Rn(ec
} M2>Vj/
b"uu
public int getCountByCriteria(final .B]MpmpK
HU8900k+
DetachedCriteria detachedCriteria){ v6M6>&RR|
Integer count = (Integer) nn:.nU|I
Ng2@z<>.
getHibernateTemplate().execute(new HibernateCallback(){ ll<Xz((o
publicObject doInHibernate k"T}2 7
Sw8]EH6
(Session session)throws HibernateException { j_!F*yul
Criteria criteria = +>Qq(Y
RXpw!
detachedCriteria.getExecutableCriteria(session); ^& tZ
return vv3*
j&I
J6s`'gFns
criteria.setProjection(Projections.rowCount QT<
}]
0
EyD=q! ZVZ
()).uniqueResult(); X<`
} +,TRfP
Fb
}, true); pMx*F@&nU
return count.intValue(); |+FubYf?$
} G C),N\@Q
} 1#V_Z^OL
hYT0l$Ng
<
Mn ;
/yDz/>ID\
\}u
Y'F
zU kgG61
用户在web层构造查询条件detachedCriteria,和可选的 BOb">6C
g|DF[
startIndex,调用业务bean的相应findByCriteria方法,返回一个 xaq-.IQAM$
Z58X5"
PaginationSupport的实例ps。 1b `1{%
k2omJ$?v
ps.getItems()得到已分页好的结果集 V%7WUq
ps.getIndexes()得到分页索引的数组 M)J5;^["
ps.getTotalCount()得到总结果数 EnKR%Ctw
ps.getStartIndex()当前分页索引 1y4|{7bb
ps.getNextIndex()下一页索引 :}L[sl\R
ps.getPreviousIndex()上一页索引 'Vzp2
o8V5w!+#
9N#_(uwt
9|^2",V
X:f UI4
!1jBC.G1
v+W&9>
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 vjbASFF0=
,8S/t+H
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 d\&U*=
n$MO4s8)
一下代码重构了。 KB3Htw%W[+
e/KDw
我把原本我的做法也提供出来供大家讨论吧: rT=rrvV3g
0#7>o^2
首先,为了实现分页查询,我封装了一个Page类: 1*P~!2h
java代码: [SjqOTon{
Q,,e+exbb5
B?eCe}*f;B
/*Created on 2005-4-14*/ L\6M^r
>
package org.flyware.util.page; @+&LYy72
R~TTL
/** 5N#aXG^9
* @author Joa JinUV6cr
* bbDZ#DK"
*/ >2Y=*K,:
publicclass Page { !4ocZmj\
6iry6wcHm
/** imply if the page has previous page */ z 4e7PW|
privateboolean hasPrePage; u4*BX&
f%A;`4`q
/** imply if the page has next page */ :tc@2/>!O
privateboolean hasNextPage; vOH4#
vSGH[nyCY
/** the number of every page */ ~T"Rw2vb
privateint everyPage; %HhBt5w
^Y?k0z
/** the total page number */ /m!BY}4W
privateint totalPage; ^L,K& Jd
+i6GHBn~J
/** the number of current page */ v1#otrf
privateint currentPage; WSPI|#Xr%
3#n_?-
/** the begin index of the records by the current [DYQ"A=)d
m=1N>cq
'
query */ !K#qe Y}
privateint beginIndex; K$z2YJ%
Ml`:UrU
f'F?MINJP
/** The default constructor */ ImA @}:
public Page(){ ^23~ZHu
RV1coC.g4x
} zWnX*2>b
YByLoM*
/** construct the page by everyPage 0RzEY!9g+
* @param everyPage ~\r*
* */ 1Te%F+7
public Page(int everyPage){ MnmVl"(/
this.everyPage = everyPage; "BAK !N$9
} [=C6U_vU
g/4[N{Xf
/** The whole constructor */ 2bz2KB5>
public Page(boolean hasPrePage, boolean hasNextPage, ??5Q)Erm1
}YQX~="
REQ\>UO_
int everyPage, int totalPage, HH`'*$]7
int currentPage, int beginIndex){ 9p85Pv [M=
this.hasPrePage = hasPrePage; ]IaMp788
this.hasNextPage = hasNextPage; SV4E0c>
this.everyPage = everyPage; .C%<P"=J4h
this.totalPage = totalPage; eb"VE%+Hu
this.currentPage = currentPage; &{5,:%PXw
this.beginIndex = beginIndex; EZgwF=lO
} ]U?^hZ_
H;is/
/** =<C:d
* @return `K"L /I9
* Returns the beginIndex. oE@a'*.\
*/ Brw@g8w-X
publicint getBeginIndex(){ SZ7:u895E
return beginIndex; BX/8O<s0
} 2B1q*`6R
yNBQGSH
/** alJ)^OSIe
* @param beginIndex m~BAyk^jo3
* The beginIndex to set. y
G~?MEh{
*/ z9f-.72"X
publicvoid setBeginIndex(int beginIndex){ E*&vy
this.beginIndex = beginIndex; B^=-Z8
} {L971W_L
@)F )S7
/** 3ZuZ/=
* @return >dXGee>'M
* Returns the currentPage. :9afg
*/ umBICC]CU
publicint getCurrentPage(){ yZ7&b&2nLn
return currentPage; HdI8f!X'TG
} [|wZ77\
u2I*-K
/** n6=By|jRh
* @param currentPage Z3e| UAif
* The currentPage to set. wSL}`C gU
*/ `cn#B
BV
publicvoid setCurrentPage(int currentPage){ .8g)av+
this.currentPage = currentPage; y8Ir@qp5
} m,28u3@r
;1W6G=m
/** j3oV+zZ49
* @return }v;V=%N+v
* Returns the everyPage. h8j.(
*/ yF:1( 4
publicint getEveryPage(){ ;a!S!%.h
return everyPage; T"Y+m-<%
} TprTWod2]t
@u+]aI!`-
/** OO\+J
* @param everyPage ;}WeTA_-[
* The everyPage to set. ]EbM9Fo-U
*/ uC vj!
publicvoid setEveryPage(int everyPage){ Jrf=@m\dk
this.everyPage = everyPage; %Xd[(Q)
} + 480 l}
&E F!OBR
/** ssA`I<p #
* @return uc{Ihw
* Returns the hasNextPage. Q} JOU
*/ (Rh,,
publicboolean getHasNextPage(){ hag$GX'2k
return hasNextPage; P5V}#;v
} "{+QW
c]<5zyl"j1
/** Es`Px_k
* @param hasNextPage 2qNt,;DQ
* The hasNextPage to set. qo~O|~
*/ octL"t8w
publicvoid setHasNextPage(boolean hasNextPage){ s^TZXCyF o
this.hasNextPage = hasNextPage; X`/k)N>l
} 3%|&I:tI
CW K7wZM
/** (m}'4et~L
* @return S?LQu
* Returns the hasPrePage. gg/-k;@ Rf
*/ uMv,zO5
publicboolean getHasPrePage(){ cZ*@$%_
return hasPrePage; Hio0HL-
} E=Bf1/c\
zI uJ-8T"
/** Zl!kJ:0
* @param hasPrePage ~=LE0. 3[
* The hasPrePage to set. DfD&)tsMQ
*/ >6-`}G+|
publicvoid setHasPrePage(boolean hasPrePage){ UDFDJm$
this.hasPrePage = hasPrePage; Qel9G($=
} LOYk9m
gVuFHHeUz
/** e%M;?0j
* @return Returns the totalPage.
K5 z<3+
* ue"~9JK.
*/ ]/6z;
~3U
publicint getTotalPage(){ @
q3k%$4
return totalPage; 8Fh)eha9f
} 372rbY
RB\uK
1+
/** /nsX]V6i
* @param totalPage T!{w~'=F
* The totalPage to set. T>Z<]s
*/ 8,%^
M9zBP
publicvoid setTotalPage(int totalPage){ wlvgg
this.totalPage = totalPage; Izc\V9+
} kTB0b*V
l'qg8
} j (d~aqW
Zi
i
}.(B}/$u
o|:b;\)b
*^4"5X@
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 3hH<T.@)
_VN?#J)o
个PageUtil,负责对Page对象进行构造: w&#]-|$
java代码: O bS3
M
"S]TP$O D
6gE7e|+
/*Created on 2005-4-14*/ e !Y~Qy
package org.flyware.util.page; AT3Mlz~7#
X_h}J=33Q
import org.apache.commons.logging.Log; LL!Dx%JZ
import org.apache.commons.logging.LogFactory; Kc-W&?~y#1
~
7s!VR
/** <'*LRd$1
* @author Joa \8cx6 G'
* ?`ZUR&
20
*/ CTa57R
publicclass PageUtil { 4HlQ&2O%#
S\=Nn7"
privatestaticfinal Log logger = LogFactory.getLog ?a5! H*,
0h_|t-9j
(PageUtil.class); 3pKQ$\u
H{wl% G
/** 7:1Lol-V
* Use the origin page to create a new page :I#V.
* @param page 5]0<9a
* @param totalRecords } Kgy
* @return '=pU^Oz<}
*/ ,J@
publicstatic Page createPage(Page page, int !|(NgzDP/
{wKB;?fUvk
totalRecords){ g-
gV2$I
return createPage(page.getEveryPage(), z}
#JK?u
4pvMd
page.getCurrentPage(), totalRecords); 7[)E>XRE
} Z T%5T}i
!Uo4,g6r+
/** @VEb{ w[H
* the basic page utils not including exception 2^7`mES
z{QqY.Gu{G
handler =s6 opL)
* @param everyPage Bzf^ivT3L
* @param currentPage ]-#DB^EQ
* @param totalRecords _[BP0\dPW
* @return page ;$4\e)AB
*/ ;xTpE2 -~
publicstatic Page createPage(int everyPage, int {JLtE{
%|oym.-I6
currentPage, int totalRecords){ {.Jlbi9!
everyPage = getEveryPage(everyPage); d=/F}yP~?s
currentPage = getCurrentPage(currentPage); %cn<ych
G
int beginIndex = getBeginIndex(everyPage, ;^L(^Hx
-9?]IIVb
currentPage); n$R)>nY
int totalPage = getTotalPage(everyPage, .%-8 t{dt
%]i15;{X
totalRecords); BgT*icd8d
boolean hasNextPage = hasNextPage(currentPage, #'}*dy/
6y<EgYzdE
totalPage); kJR`:J3DJ
boolean hasPrePage = hasPrePage(currentPage); (9)Q ' 'S
zH
r_!~
returnnew Page(hasPrePage, hasNextPage, <_+X 88
everyPage, totalPage,
='jT~\
currentPage, cMIEtK`
E{(;@PzE
beginIndex); *
y,v}-
} *qq+jsA6wH
y();tsWqc
privatestaticint getEveryPage(int everyPage){ t{>q|0
return everyPage == 0 ? 10 : everyPage; b.938#3,
} vDvFL<`vmD
MQ2_`pi
privatestaticint getCurrentPage(int currentPage){ j<$2hiI/?&
return currentPage == 0 ? 1 : currentPage; EQ_aa@M7
} ssL\g`xe
\)e'`29;
privatestaticint getBeginIndex(int everyPage, int w-jVC^C]
AXB7oV,xt
currentPage){ CC`JZ.SO
return(currentPage - 1) * everyPage; I1J-)R+
} I^]nqK
H?w6C):]
privatestaticint getTotalPage(int everyPage, int dN6?c'iN?2
i#O SC5ZI
totalRecords){ VEH>]-0K
int totalPage = 0; ^J{:x
EM_d8o)`B
if(totalRecords % everyPage == 0) E-FUlOG&
totalPage = totalRecords / everyPage; #9s,#
}
else TqQ[_RKg2
totalPage = totalRecords / everyPage + 1 ; +T+#q@
JGZBL{8
return totalPage; "M0z(NkH
} Ul# r
:'ptuY
privatestaticboolean hasPrePage(int currentPage){ jWgX_//!
return currentPage == 1 ? false : true; A}w/OA97RO
} 3c%caK
8CE = 4
privatestaticboolean hasNextPage(int currentPage, $Kd>:f=A
3U}%2ARo_
int totalPage){ wM{s|Ay
return currentPage == totalPage || totalPage == 8,|k ao:
d_CT$
0 ? false : true; T4F/w|Q
} z!\*Y
=e
62u4-}JzF
k{0o9,
} d5 -qZ{W
}a/Cro.~4
0"#HJA44
1*7@BP5
?cZlN!
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。 2zpr~cB=
8k79&|
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 W3RT{\
QL* IiFR
做法如下: R-Sym8c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 cCX*D_kCB
^@]3R QB
的信息,和一个结果集List: .^.z2
e
java代码: 7z-[f'EIUI
}7X%'Bg=M
K^[?O{x^B
/*Created on 2005-6-13*/ Pz^544\~ou
package com.adt.bo; %)wjR/o
v,t:+
!8
import java.util.List; W!<U85-#S
r*Xuj=
import org.flyware.util.page.Page; SX*RP;vHy
KSL`W2}
/** pJ{Y
lS{
* @author Joa svSVG:48
*/ /<3UQLMa
publicclass Result { &wX]_:?
cZ06Kx..
private Page page; e# bn#
##{taR8
private List content; w>YDNOk
\Cj B1]I
/** YzWz|
* The default constructor W%J\qA
*/ t^L]/$q
public Result(){ *`U~?q}
super(); e;jdqF~v!
} a9 G8q>h]O
ww/Uzv
/** {8aTV}Ha2
* The constructor using fields }M+7T\J!
* Y0>y8UV
* @param page 626r^c=
* @param content .u:GjL'$
*/ 26nx`w?j(
public Result(Page page, List content){ ceV}WN19l
this.page = page; 7L??ae
this.content = content; Vc2`b3"Br
} L$-T,Kze
RZ7@cQY
/** l\mPHA23
* @return Returns the content. ise-O1'
*/ kl`W\t F
publicList getContent(){ pFXEu=$3
return content; w@b)g
} /\Ef%@
Qd-A.{[h
/** Zh,71Umz
* @return Returns the page. +H.`MZ=
*/ xmG<]WF>E
public Page getPage(){ .h[:xYm
return page; [~
fraK,)
} RpK@?[4s
:svqE+2
/** *fdTpXa
* @param content gSgr6TH0
* The content to set. yr6V3],Tp
*/ Tk>#G{Wb-
public void setContent(List content){ (ZGbhMK
this.content = content; g\U-VZ6;p
} )7d&NE_
S 5U;#H
/** pJ=#zsE0
* @param page GeqPRah
* The page to set. >7FHo-H/T
*/ C+]I@Go'Tk
publicvoid setPage(Page page){ =vPj%oLp'a
this.page = page; ;
KA~Z5x;
} z{6Z
11|
} Zc yc*{DS
H.;Q+A,8^
*I+Q~4
>sF)BoLc
5tnlrqC
2. 编写业务逻辑接口,并实现它(UserManager, No$3"4wk
9^x> 3Bo
UserManagerImpl) <$YlH@;)`a
java代码: "|NI]Kv
YQ}o?Q$z
H+#FSdy#
/*Created on 2005-7-15*/ -4K5-|>O
package com.adt.service; t:S+%u U
~~.}ah/_d
import net.sf.hibernate.HibernateException; ]iWRo'
E$e5^G9
import org.flyware.util.page.Page; NHt\
U9l'
7^Uv7<pw
import com.adt.bo.Result; V+\Wb[zDJ
3%6?g*
/** 0]L"H<W
* @author Joa k+/6$pI
*/ m~|40)
publicinterface UserManager { "MsIjSu
/1 dT+>
public Result listUser(Page page)throws ~Ei<Z`3}7"
YUb_y^B^
HibernateException; F@t3!bj9
!Cs_F&l"j
} #mT"gs
V9vTsmo(
Wqnc{oq|$
VTM/hJmwJ
n<,BmVQ
java代码: ~o(
1 zZlC#V
e.> P8C<&
/*Created on 2005-7-15*/ e.C)jv6qr
package com.adt.service.impl; =l6mL+C
!i50QA|(G
import java.util.List; Gt1U!dP
u,
ff>/1
import net.sf.hibernate.HibernateException; pmM9,6P4@
| Iib|HQ)
import org.flyware.util.page.Page; ;gkM{={`p
import org.flyware.util.page.PageUtil; [
3Gf2_
b
6p|q_e
import com.adt.bo.Result;
Hz~zu{;{J
import com.adt.dao.UserDAO; do%&m]#;
import com.adt.exception.ObjectNotFoundException; !VJoM,b8
import com.adt.service.UserManager; {=WgzP
+0&/g&a\R
/** PsYpxNr
* @author Joa 8y L Y
*/ |=w@H]r
publicclass UserManagerImpl implements UserManager { >%G1"d?j
&&+H+{_Q
private UserDAO userDAO; XUYtEf
A<{{iBEI`
/** r"
y.KD^
* @param userDAO The userDAO to set.
}pYqWTG
*/ t!XwW$@
publicvoid setUserDAO(UserDAO userDAO){ Q?vlfZR`8
this.userDAO = userDAO; *p U x8yB
} JI}'dU>*U:
Nc`L;CP
/* (non-Javadoc) gJXaPJA{
* @see com.adt.service.UserManager#listUser WE?5ehEme
yAt^;
(org.flyware.util.page.Page) kj_c%T
]/
*/ 3u=g6W2 F
public Result listUser(Page page)throws ?
t|[?
a9gLg
&
HibernateException, ObjectNotFoundException { (HVGlw'`
int totalRecords = userDAO.getUserCount(); [WmM6UEVS
if(totalRecords == 0) ~Y;*u]^
throw new ObjectNotFoundException $i&zex{\
t_^4`dW`
("userNotExist"); HfVZ~PP
page = PageUtil.createPage(page, totalRecords); Hka2
List users = userDAO.getUserByPage(page); AH^/V}9H
returnnew Result(page, users); A"]YM'.
} p{_" bB
Y4-t7UlS;
} Ac@VGT:9
3BI1fXT4=j
7! Nsm
R&&4y 7
HN"Z]/5j
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 h{Y",7]!
By|4m
询,接下来编写UserDAO的代码: s;e\ pt
3. UserDAO 和 UserDAOImpl: aN?zmkPpov
java代码: 7#XzrT]
7.Op<
)7F/O3Tq
/*Created on 2005-7-15*/ %J(:ADu]
package com.adt.dao; e6*8K@LHB
=cI(d ,
import java.util.List; 0J9x9j`&j
vXs"Dst
import org.flyware.util.page.Page; 79gT+~z
uRvP hkqm
import net.sf.hibernate.HibernateException; o!Zb0/AP)
)nkY_'BV
/** u`W2+S
* @author Joa K-v#.e4
*/ B\~}3!j
publicinterface UserDAO extends BaseDAO { -@'FW*b
oA
1yIp
publicList getUserByName(String name)throws /^ts9:
E GU2fA7x
HibernateException; A.SvA Yn
6K^#?Bn;
publicint getUserCount()throws HibernateException; |yCMt:Hk
M`_0C38
publicList getUserByPage(Page page)throws Jy)/%p~
C|bET
HibernateException; _BufO7`.
&C}*w2]0S
} U^PgG|0N
&ZO0r ^
hN_]6,<\
=;L|gtH"
$xsd~L&
java代码: wYea\^co
}f ?y*
H
).O)p9
/*Created on 2005-7-15*/ _`X:jj>
package com.adt.dao.impl; tQVVhXQ7
]Ljf?tk
import java.util.List; kh<2BOV
h[ ZN+M
import org.flyware.util.page.Page; Py<}S-:
u8^lB7!e/
import net.sf.hibernate.HibernateException; 6Wn1{v0
import net.sf.hibernate.Query; +@UV?"d
9r9NxKuAO
import com.adt.dao.UserDAO; 7zMr:JmV
S:}7q2:
/** , gHDx
* @author Joa [g,}gyeS(
*/ Ri'n
public class UserDAOImpl extends BaseDAOHibernateImpl C~[,z.FvO
SuznN
L=/$
implements UserDAO { g`^x@rj`E
"b[5]Y{
U
/* (non-Javadoc) IID5c"
oR
* @see com.adt.dao.UserDAO#getUserByName e)ZUO_Q$
u-TUuP
(java.lang.String) p<2,=*2
*/ Q?T]MUY(L
publicList getUserByName(String name)throws >p/`;Kq@
.543N<w
HibernateException { zX~MC?,W1
String querySentence = "FROM user in class u>$t'
WHI`/FM
com.adt.po.User WHERE user.name=:name"; g>sSS8RO
Query query = getSession().createQuery ':W[ A
OB7hlW
(querySentence);
5uf a
query.setParameter("name", name); 8Y3I0S
return query.list(); h~26WLf.
} eFAnFJ][L
7.T?#;'3
/* (non-Javadoc) 9kojLqCT
* @see com.adt.dao.UserDAO#getUserCount() KG@8RtHsQ
*/ ]?)TdJ`
publicint getUserCount()throws HibernateException { [Yyk0Qv|4
int count = 0; OTp]Xe/
String querySentence = "SELECT count(*) FROM q =Il|Nb>
nie% eC&U
user in class com.adt.po.User"; $|@ r!/W
Query query = getSession().createQuery OH"XrCX7n
a>)f=uS
(querySentence); Q^I\cAIB
count = ((Integer)query.iterate().next P&q7|ST%N
?8 {"x8W;
()).intValue(); {|\.i
return count; }i2V.tVB-
} ]HdCt 3X
7Qsgys#/=
/* (non-Javadoc) iCyfOh
* @see com.adt.dao.UserDAO#getUserByPage 875od
p#[.{
(org.flyware.util.page.Page) -![|}pX
*/ dTtSUA|V7"
publicList getUserByPage(Page page)throws 80;(Gt@<"
v
LZoa-w:
HibernateException { vFsLY
String querySentence = "FROM user in class @P"p+
c"Sq~X
com.adt.po.User"; Bj~+WwD)QR
Query query = getSession().createQuery 'RRE|L,
y?:.;%!E
(querySentence); \;-|-8Q
query.setFirstResult(page.getBeginIndex()) 9/7u*>:
.setMaxResults(page.getEveryPage()); ?rIx/>C9
return query.list(); g*"P:n71
} wf$s*|z
G9:l'\
} * 4Izy14e
l+R+&b^
?
qA]w9x
EZj9wd"u
_[y/Y\{I
至此,一个完整的分页程序完成。前台的只需要调用 ~,~eoW7
Q|L~=9
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;\l,5EG
63A.@mL
的综合体,而传入的参数page对象则可以由前台传入,如果用 j)GtEP<n#
YF:L)0H'O
webwork,甚至可以直接在配置文件中指定。 J")#I91
)Beiu*
下面给出一个webwork调用示例: iyp=lLk
java代码: ``Un&-Ms
S+2(f> Z
J'2X&2
/*Created on 2005-6-17*/ t_suF$
package com.adt.action.user; ujucZ9}yd
+'@Dz9:>
import java.util.List; $j?1g#
2"S}bfrX
import org.apache.commons.logging.Log; Z:7fV5b(
import org.apache.commons.logging.LogFactory; nQ L@hc
import org.flyware.util.page.Page; W,-g=6,
$2el&I
import com.adt.bo.Result; D1mfm.9_r^
import com.adt.service.UserService; =kqt
import com.opensymphony.xwork.Action; \B
7tX
i2^>vYCsl
/** 8h4'(yGQQW
* @author Joa jb;hcraR
*/ C{bgkzr
publicclass ListUser implementsAction{ e NafpK
Jdp3nzM^^@
privatestaticfinal Log logger = LogFactory.getLog HX{`VahE
~| 6[j<ziL
(ListUser.class); F.v{-8GV
T${Q.zHY[!
private UserService userService; 9!DQ~k%
=iD3Yt
private Page page; 14'45
7(
2{'r
privateList users; :$9tF>
P}G+4Sk
/* ~BkCp pI
* (non-Javadoc) ^Js9 s8?$
* % -e 82J1
* @see com.opensymphony.xwork.Action#execute() 5-xX8-ElYz
*/ L`EBfz\n
publicString execute()throwsException{ KFkoS0M5|
Result result = userService.listUser(page); 9,'ncw$/C
page = result.getPage(); V}NbuvDB@
users = result.getContent(); }<y7bqA
return SUCCESS; +|>kCtZH%
} 5j-YM
.Twk {p
/** xLZG:^(I
* @return Returns the page. `P;s8~
*/ 3K/MvNI>
public Page getPage(){ a,#j =
return page; JOim3(5?s
} h@WhNk7"xa
\qK&q
/** X<; f
* @return Returns the users. h_IDO%
*/ X=8{$:
publicList getUsers(){ p >t#@Eu|
return users; 7y@Pa&^8
} u4%Pca9(=
c+nq] xOs'
/** 3+fp2
* @param page 4G>H
* The page to set. t; {F%9j{
*/ N;j)k;
publicvoid setPage(Page page){ Gvqxi|
this.page = page; K$_0`>[
} #@~+HC=
r|PB*`
/** <r`2)[7N
* @param users /&+tf*
* The users to set. 6N
S201o
*/ xzZ38xIhV
publicvoid setUsers(List users){ /j|G(vt5
this.users = users; b4ONh%
} in- HUG
xZwLlY
/** vucxt }Ti
* @param userService +sUFv)!4
* The userService to set. pF Rg?-
*/ 4'A!; ]:
publicvoid setUserService(UserService userService){ DOJ N2{IP
this.userService = userService; 9!}8UALD
} TS9|a{j3!
} Rt!FPoN,y
usCt#eZK
.1Al<OLL
8Sh54H
|O9O )o
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, b@f$nS
B
?Yk.$90
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 OAkZKG|
5r8<7g:>C
么只需要: <Fc;_GG
java代码:
QPg8;O
HxK80mJ
% <*g!y `
<?xml version="1.0"?> lXiKY@R#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork *b/`Ya4
oxkoA
1.0//EN" "http://www.opensymphony.com/xwork/xwork- iIa'2+
.=;3d~.]
1.0.dtd"> =&2Lb
D
(mj7oB
<xwork> M
.JoHH
W$OG(m!W>
<package name="user" extends="webwork- s<_)$}
87P>IO
interceptors"> *HO}~A%Lx
ps%q9}J
<!-- The default interceptor stack name M)N?qRD
C/kW0V7
--> 0#&5.Gr)
<default-interceptor-ref PCM-i{6/
t&CJ%XP
name="myDefaultWebStack"/> ,:H\E|XeBw
.#Z%1U%P.
<action name="listUser" ReI/]#Us
r1LViK
class="com.adt.action.user.ListUser"> aL%AQB,
<param "a1n_>#Fb
Z2='o_c
name="page.everyPage">10</param> ac.Ms (D
<result RUT,Y4 b
k"]dK,,
name="success">/user/user_list.jsp</result> \\7ZWp\fN
</action> }36QsH8
xAe~]k_D
</package> >U*T0FL7
[4C:r!
</xwork> TGe;HZ
yA(K=?sq
okv 1K
[tA;l+Q\&
[P7N{l=I
R Yl>
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ";Rtiiu
)5U[o0td
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 D]~MC
W.0L:3<"
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 H&
Ca`B
FE!lok
S"$m]
'07P&g-
!M]\I &
我写的一个用于分页的类,用了泛型了,hoho $3uKw!z
i?e`:}T
java代码: %\r!7@Q
oK%K}{`
?Ovqp-sw
package com.intokr.util; ]U7KLUY>:
yK2^Y]Ku?
import java.util.List; /E5 5Pec
~Oq +IA~9
/** `8>Py~
* 用于分页的类<br> B7<Kc
* 可以用于传递查询的结果也可以用于传送查询的参数<br> QtqfG{
* z7Eg5rm|QZ
* @version 0.01 adi[-L#
* @author cheng 1YJC{bO
*/ 1`9xIm*9w
public class Paginator<E> { BQ2wnGc
privateint count = 0; // 总记录数 \Z/)Y;|mi0
privateint p = 1; // 页编号 UNi`P9D]3
privateint num = 20; // 每页的记录数 JA_BKA
privateList<E> results = null; // 结果 -yg?V2
Io|Aj
/** j$Je6zq0x
* 结果总数 R
&4Z*?S
*/ yxq}QSb \3
publicint getCount(){ mA@Me7m}
return count; <P;}unq.kw
} U(;&(W"M
(%:>T Q(
publicvoid setCount(int count){ NwR}yb6
this.count = count; \VFHHi:I
} 0%
#<c p
Q;J`Q wkH
/** TSsKfexQ
* 本结果所在的页码,从1开始 :BGA.
* u}|%@=xn
* @return Returns the pageNo. Q9&kJ%Mo
*/ @hImk`&[N
publicint getP(){ ?kz+R'
return p; lM[XS4/TRa
} )
(Tom9^
F[!ckes<bB
/** |fY/i]
Ax
* if(p<=0) p=1 v^7LctcVm
* ZB[Qs
* @param p OLj\-w^
*/ ,*@AX>
publicvoid setP(int p){ D*Q.G8(
if(p <= 0) P0-Fc@&Y
p = 1; l@hjP1o
this.p = p; 0G2g4DSKD
} =_8Tp~j
Wi}FY }f
/** pBC<u
* 每页记录数量 35*\_9/#
*/ 9ElCg"
publicint getNum(){ oiX"Lz{
return num; S-nlr@w8
} qJ_1*!!91
Ij'NC C
/** -n? g~(/P
* if(num<1) num=1 p=QYc)3F
*/ 3?s ?XAh
publicvoid setNum(int num){ -)y%~Zn
if(num < 1) ^5 t
num = 1; d'9:$!oz
this.num = num; oAZh~~tp
} Q^Bt1C
k 2%S`/:
/** qUF1XJZ}z
* 获得总页数 \BI/G
*/ 1[;@AE2Y
publicint getPageNum(){ 8 )\M:s~7&
return(count - 1) / num + 1; '7im
} I}Xg&-L
XDD<oo
/** fH8!YQG8$
* 获得本页的开始编号,为 (p-1)*num+1 ~-F?Mc
*/ !
qJI'+_
publicint getStart(){ cub<G!K
return(p - 1) * num + 1; n`;R pr&
} $'[q4 wo<
r5/R5Ga^
/** ]9S`[c$
* @return Returns the results. <V_7|)'/A
*/ []&(D_e"
publicList<E> getResults(){ Z# Lx_*p]Q
return results; hQgN9S5P
} q3'o|pp
[B?z1z8l
public void setResults(List<E> results){ xNN@ 1P[*
this.results = results; }G1&]Wt_
} I*1S/o_xI
CM~MoV[k7e
public String toString(){ -'C!"\%
StringBuilder buff = new StringBuilder a]VGUW-
vg8O]
YF
(); U 0ZB^`
buff.append("{"); }BN\/;<A
buff.append("count:").append(count); >v0 :qN7|
buff.append(",p:").append(p); )XVh&'(r
buff.append(",nump:").append(num); cINHH !v
buff.append(",results:").append ~/`X*n&
&P n]
(results); Gidkt;lj
buff.append("}"); [{PqV):p
return buff.toString(); }#aKFcvg
} ]R Mb,hJ
H,>#|F
} 2;N@aZX
U4_"aT>My
0MpS4tW0=