Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Dkyw3*LCn%
:k/Z|
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 s2kom)
:ceT8-PBRx
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 Va-.
GNX`~%3KYc
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 -qs
R,H
L "[>tY
。 >HRL@~~Z
0
zn }l6OS
分页支持类: Qz4n%|
{oVoN>gp
java代码: @Wl2E.)K;
=N^j:t
^&!iq K2o
package com.javaeye.common.util; /cC4K\M
t2Y2v2 J
import java.util.List; I&Z+FL&@f
OhW o
publicclass PaginationSupport { L|y9T{s
XGcl9FaO}
publicfinalstaticint PAGESIZE = 30; Mh@RO|F
LXq0hI
privateint pageSize = PAGESIZE; S4C4_*~Vd
=u<jxV9
privateList items; q]rqFP0C
e13' dCG
privateint totalCount; S%IhpTSe6
VlFhfOR6t
privateint[] indexes = newint[0]; p/ au.mc
Mh"vH0\Lj
privateint startIndex = 0; #!7b3 >}
Aq,&p,m03
public PaginationSupport(List items, int I~T~!^}U
*5z"Xy3J
totalCount){ K06x7W
setPageSize(PAGESIZE); fl+dL#]
setTotalCount(totalCount); 9R3YUW}s
setItems(items); 2*pNIc
setStartIndex(0); *}RV)0mif
} COFCa&m9c
b~Un=-@5a
public PaginationSupport(List items, int qk_YFR?R
['_W<
totalCount, int startIndex){ #4Ltw,b^
setPageSize(PAGESIZE);
H$!sK
setTotalCount(totalCount); /L;
c -^
setItems(items); V2o1~R~
setStartIndex(startIndex); 58[.]f~0
} zOn%\
%'&_Po\
public PaginationSupport(List items, int Gq =i-I
\:Z8"~G
totalCount, int pageSize, int startIndex){ owe6ge7m
setPageSize(pageSize); Q60'5Wt
setTotalCount(totalCount); Q7pjF`wu
setItems(items); d37|o3oC
setStartIndex(startIndex); r68d\N`.
} %mNd9 ]<
XLj|y#h
publicList getItems(){ 4;)aGN{e
return items; Psw<9[
} NxrfRhaU3
2|JtRE+
publicvoid setItems(List items){ OR<%h/ \f
this.items = items; .9$
7
+
} D[Kq`
0}wmBSl
publicint getPageSize(){ 4|/=]w
return pageSize; qK,PuD7i"
} Ry`Y +
6fV;V:1{
publicvoid setPageSize(int pageSize){ ^+u/Lw&
this.pageSize = pageSize; UhbGU G
} ,Wlw#1fP
1+9}Xnxb
publicint getTotalCount(){ ,niQs+'<
return totalCount; S&{#sl#e
} AI9#\$aGV
@%gth@8
publicvoid setTotalCount(int totalCount){ k[8{N
if(totalCount > 0){ C7_nA:Rc
this.totalCount = totalCount; |`Q2K9'4bL
int count = totalCount / O>/&-Wk=
W3y9>]{x^
pageSize; nRh.;G
if(totalCount % pageSize > 0) q4]Qvf>
count++; sG:tyvln
indexes = newint[count]; A ^X 1
for(int i = 0; i < count; i++){ H'x)[2
indexes = pageSize * Q)93+1]
W3]?>sLE*
i; 6GsB*hW
} kA{eT
}else{ E=RX^ 3+}
this.totalCount = 0; gi
JjE
} j7
\y1$w
} f!13Ob<8r
P*3PDa@
publicint[] getIndexes(){ f;]C8/ W
return indexes; 2'7)D}p
} :0vKt 6>Sp
_&K>fy3t&
publicvoid setIndexes(int[] indexes){ !H4C5wDu
this.indexes = indexes; !f)^z9QX8
} r@ v&~pL
;C~:C^Q\H
publicint getStartIndex(){ UUDZ
return startIndex; 1aS66TS3
} KpfQ=~'
"q3W&@
publicvoid setStartIndex(int startIndex){ @9\L|O'~?
if(totalCount <= 0) #s0Wx47~
this.startIndex = 0; cOb,Md
elseif(startIndex >= totalCount) `c /mmS
this.startIndex = indexes fB`7f
$[
o>@9[F,h+
[indexes.length - 1]; _7N^<'B
elseif(startIndex < 0) A ?ij
this.startIndex = 0; B;^YHWJ6i
else{ Mo0pN\A}h
this.startIndex = indexes Z
lR2
<gjA(xT5
[startIndex / pageSize]; VD+y4t'^
} 4j}uVGi{e
} +dJLT}I8M
i~uoK7o|G
publicint getNextIndex(){ H\<^p",`
int nextIndex = getStartIndex() + -"/l)1ox,
n--w-1
pageSize; iU "{8K,
if(nextIndex >= totalCount) T )"Uq
return getStartIndex(); TUM7(-,9
else <BhNmEo)2
return nextIndex; +JPHQx'W
} |>jlmaV
S|/Za".Gr
publicint getPreviousIndex(){ nYts[f9e
int previousIndex = getStartIndex() - TY]-L1$
*S] K@g
pageSize; ?/FCq6o
if(previousIndex < 0) .Uh|V-
return0; /r Z`e'}
else Uq:CM6q\
return previousIndex; 95b65f
} SZL('x,"^
mFW/xZwR,5
} ?b3({P
6/l{e)rX2o
w6@8cNXK
N^xk.O_TO
抽象业务类 AlhPT (
java代码: } DQ KfS
P=
nu&$;
v>E3|w%
/** v 8NoD_
* Created on 2005-7-12 CK#SD|~:
*/ 7$|L%Sk
package com.javaeye.common.business; W
B7gY\Y&M
[FN4 _
import java.io.Serializable; ;ep@
)Y
import java.util.List;
:JfT&YYi"
Nk@a g)
import org.hibernate.Criteria; _p,1m[&M
import org.hibernate.HibernateException; Oj0,Urs7
import org.hibernate.Session; m1,yf*U
import org.hibernate.criterion.DetachedCriteria; Olltu"u
import org.hibernate.criterion.Projections; jb0LMl}/A
import bYB:Fe=2
~-K<gT/
org.springframework.orm.hibernate3.HibernateCallback; /4bHN:I]M
import z<z\)
kbKGGn4u
org.springframework.orm.hibernate3.support.HibernateDaoS @&}~r
{+^qm8n
upport; m5KAKpCR,
O
cJ(i#Q~<
import com.javaeye.common.util.PaginationSupport; oC >l|?h,
pjrzoMF
public abstract class AbstractManager extends 4j VFzO%.
X2S:"0?7
HibernateDaoSupport { bbAJ5EqL
v]e6CZwo
privateboolean cacheQueries = false; ns`njx}C
<OA[u-ph%S
privateString queryCacheRegion; e'L$g-;>4b
sB'Z9
publicvoid setCacheQueries(boolean &#DKB#.2
6Cz%i6)
cacheQueries){ 3,$G?auW
this.cacheQueries = cacheQueries;
Z
Vj
} BIeeu@p
(5R_q.Wu
publicvoid setQueryCacheRegion(String z2DjYTm[~
_1U7@v:<@
queryCacheRegion){ ebmU~6v k
this.queryCacheRegion = xYl ScM_~
ED=P
6u
queryCacheRegion; HqKI|^
} {Tl |>\[P
f<}>*xH/k
publicvoid save(finalObject entity){ !K5D:x
getHibernateTemplate().save(entity); i\94e{uty[
} &I=F4 z
m*
JbZT
publicvoid persist(finalObject entity){ -na oM
getHibernateTemplate().save(entity); 'Nn>W5#))
} PAHkF&
d>r_a9 .u
publicvoid update(finalObject entity){ #Y;tobB
getHibernateTemplate().update(entity); ?VP07
dQTe
} H;=++Dh
RY9h^q*
publicvoid delete(finalObject entity){ N9jSiRJ
getHibernateTemplate().delete(entity); aK4ZH}XHE"
} ``9`Xq
=BNS3W6
publicObject load(finalClass entity, [7*$Sd
4E~!$Ustx
finalSerializable id){ 04wO9L;
return getHibernateTemplate().load BkcA_a:W
|*[#Iii'
(entity, id); xXn2M*g
} P
K9BowlW
Ki{]5Rz
publicObject get(finalClass entity, 'H.,S_v1x
$9m>(b/;n
finalSerializable id){ ^s[OvJb
return getHibernateTemplate().get .GH#`j
V-.Nc#
(entity, id); D8,V'n>L
} d-BUdIz
OZed+t=
publicList findAll(finalClass entity){
[Adkj
return getHibernateTemplate().find("from QH.zsqf(
T3#KuiwU9
" + entity.getName()); "{Jq6):mp
} ZXL
)mvD2]fK
publicList findByNamedQuery(finalString Tyk\l>S
]<B@g($
namedQuery){ * M,'F^E2
return getHibernateTemplate 2,.;Mdl
e~iPN.'1
().findByNamedQuery(namedQuery); PShluhY
} _8eN^oc%
ZclZD{%8J
publicList findByNamedQuery(finalString query, )/_T`cN
XEvDtDR
finalObject parameter){ 0 CFON2I
return getHibernateTemplate syR
+;
#:st>V_h
().findByNamedQuery(query, parameter); /UAcN1K!B
} dB%q`7O
xY,W[?3CY
publicList findByNamedQuery(finalString query, x;L.j7lzA;
'hn=X7
finalObject[] parameters){ @+ee0
CLT
return getHibernateTemplate NiPa-yRh
z=/xv},
().findByNamedQuery(query, parameters); QYj 8c]8f
} !1<?ddH6
j\9v1O!T
publicList find(finalString query){ ="Sa>-do,
return getHibernateTemplate().find P6
& _q
&hri4p/
(query); uBXl ltU
} pk5W!K
M);@XcS
publicList find(finalString query, finalObject U6M3,"?
k~+(X|!5w
parameter){ }'.k
return getHibernateTemplate().find pcl'!8&7
dX8N7{"[
(query, parameter); ]pi8%.d
} r|W2I,P
1deNrmp%
public PaginationSupport findPageByCriteria ?}D|]i34
1y)|m63&
(final DetachedCriteria detachedCriteria){ >nA6w$
return findPageByCriteria @+(TM5Ub
Dd:;8Xo
(detachedCriteria, PaginationSupport.PAGESIZE, 0); SC6cFyp2
} FsdxLMwk1
*'&mcEpg
public PaginationSupport findPageByCriteria Rz_fNlA
JDA :)[;
(final DetachedCriteria detachedCriteria, finalint
Y o$NE
L
dyTB@
startIndex){ RCvf@[y4
return findPageByCriteria /y~ "n4CK~
)QO"1#zg@c
(detachedCriteria, PaginationSupport.PAGESIZE, a&*fk ?o
43p0k&;-7
startIndex); f3u^:6U~
} *'q6#\#.
PIxd'B*MF
public PaginationSupport findPageByCriteria A,4|UA?-
{vL4:K
(final DetachedCriteria detachedCriteria, finalint Ka$YKY,
[EX@I
=?
pageSize, DL:wiQ
finalint startIndex){ B- `,h pp
return(PaginationSupport) +dIO+(&g
0s#`H
getHibernateTemplate().execute(new HibernateCallback(){ P$=BmBq18`
publicObject doInHibernate y:>'1"2`
@! gJOy
(Session session)throws HibernateException { >,V~-Tp
Criteria criteria = K4V\Jj1l
| ]DJz
detachedCriteria.getExecutableCriteria(session); ^3B&E^R
int totalCount = 1dg y-$H~
~VqDh*0
((Integer) criteria.setProjection(Projections.rowCount wx,yx3c (
t"]+}]O
()).uniqueResult()).intValue(); t|ih{0
criteria.setProjection _ 3l ci
|*w}bT(PfR
(null); `?H yDny
List items = @},25"x)
p[zKc2 TPk
criteria.setFirstResult(startIndex).setMaxResults vA r
fsgk
=d{B.BP(
(pageSize).list(); 9
Z5!3
PaginationSupport ps = !Xzne_V<
JQtBt2
new PaginationSupport(items, totalCount, pageSize, tf5h/:
s$,gM,|cK
startIndex); #J,?oe=<4
return ps; N5SePA\ ,?
} *C*'J7
}, true); jM'kY|<g;
} &H`A S6
>)&]Ss5J
public List findAllByCriteria(final TI9]v(
Hlr[x
DetachedCriteria detachedCriteria){ Id/-u[-yo
return(List) getHibernateTemplate s?irT;=
ky^p\dMh
().execute(new HibernateCallback(){ =@%Ukrd@
publicObject doInHibernate #Oeb3U
k[`9RGT
(Session session)throws HibernateException { W8$ky[2R
Criteria criteria = k\qF> =
)M!6y%b67
detachedCriteria.getExecutableCriteria(session); :U}.
return criteria.list(); TBGN',,
} _=wu>h&7
}, true); [vJLj>@
} I)B+h8l72<
K>tubLYh
public int getCountByCriteria(final "\x<Zg;
#'@pL0dj
DetachedCriteria detachedCriteria){ 8{t^< j$n
Integer count = (Integer) zree}VqD;5
fnwhkL#8
getHibernateTemplate().execute(new HibernateCallback(){ ~q.a<B`,t
publicObject doInHibernate 9uNkd2#
kma)DW
(Session session)throws HibernateException { /5l"rni
Criteria criteria = GbLuXU
|A'y|/)#Z
detachedCriteria.getExecutableCriteria(session); ~ryB*eZH
return j`'9;7h M6
w6RB|^
criteria.setProjection(Projections.rowCount /.{q2]
Z/r =4
()).uniqueResult(); .]0u#fz0y
} nkp,
}, true); iE~][_%U
return count.intValue(); jc4#k+sb
}
MYD`P2F
} wc%Wy|d
h2b,(
biBo?k;4
7<T1#~w4L
Q=,6W:j
$y0[AB|V
用户在web层构造查询条件detachedCriteria,和可选的 k"kGQk4
%|tDb
startIndex,调用业务bean的相应findByCriteria方法,返回一个 _{]\} =@
eVXlQO
PaginationSupport的实例ps。 ?>p(*
9ff6Apill
ps.getItems()得到已分页好的结果集 ;77#$H8)
ps.getIndexes()得到分页索引的数组 -&Cb^$.-x
ps.getTotalCount()得到总结果数 ","O8'$OC
ps.getStartIndex()当前分页索引 :?2@qWaL
ps.getNextIndex()下一页索引 Cj,Yy
ps.getPreviousIndex()上一页索引 d'oh-dj %^
p-6Y5$Y
\-]zXKl2k
l8XgzaW
p>g5WebBN
4P406,T]r
6ka,
FjJ\
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4dEfXrMf
{CO]wqEj
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 -kGwbV}
k3HPY}-
一下代码重构了。 pQ_EJX)
/tG0"1{
我把原本我的做法也提供出来供大家讨论吧: R">-h;#
nOH x^(
首先,为了实现分页查询,我封装了一个Page类: !iys\ AV
java代码: y.xyr"-Q
QgR3kc^7/
)g()b"Z
#>
/*Created on 2005-4-14*/ SH009@l_8
package org.flyware.util.page; F&Bh\C)]
r+0<A.''a
/** Z}8khNCYr
* @author Joa y:m
;_U,%c
* z(8:7 G
*/ &}:]uC
publicclass Page { ;*H@E(g
D?Mj<||
/** imply if the page has previous page */ hR g?H
privateboolean hasPrePage; /:+f5\"-b
fLtN-w6t
/** imply if the page has next page */
vj_[LFE
privateboolean hasNextPage; s U|\? pJ
M_OvIU(E
/** the number of every page */ cbton<r~
privateint everyPage; !Qqi%
eTeZ^G
/** the total page number */ ef Moi 'v
privateint totalPage; l\HLlwYO
**D3.-0u&
/** the number of current page */ 7gk}f%,3P
privateint currentPage; ;v*J:Mn/=
(}#8$ )
/** the begin index of the records by the current S`\03(zDA
I1a>w=x!+
query */ XK";-7TZt
privateint beginIndex; x$:P;#
-->~<o
g5YDRL!Wh
/** The default constructor */ #80[q3
public Page(){ -lb,0
5}+&Em":
} yMd<<:Ap
o#^(mGj_.
/** construct the page by everyPage 9tMaOm
* @param everyPage ^%qe&Pe2
* */ :pp@x*uNP
public Page(int everyPage){ Fuz'!
this.everyPage = everyPage; + n)_\@aQ
} !jySID?q
ZNKopA(=|%
/** The whole constructor */ r*r3QsO
public Page(boolean hasPrePage, boolean hasNextPage,
js$L<^7
_, ki/7{
xsO
"H8
int everyPage, int totalPage, FJ/c(K
int currentPage, int beginIndex){ -PG81F&K
this.hasPrePage = hasPrePage; ^D%hKIT
this.hasNextPage = hasNextPage; &tJ!cTA.-
this.everyPage = everyPage; ;!C~_{/t
this.totalPage = totalPage; *3Vic
this.currentPage = currentPage; #B^A"?*S
this.beginIndex = beginIndex; "KiTjl`M,
} fHLt{ !O
xpU7ZY
/** l9P=1TL
* @return p9(|p Z
* Returns the beginIndex. R ^ln-H;
*/ \Zgc
[F
publicint getBeginIndex(){ %$*WdK#
return beginIndex; }3TTtd7
} rP7[{'%r
P&=H<^yd
/**
# h/#h\
* @param beginIndex %aB
RL6
* The beginIndex to set. jY +u OH
*/ .,9e~6}
publicvoid setBeginIndex(int beginIndex){ YjR`}rdwo
this.beginIndex = beginIndex; {tDH !sX
} \Qgc7ev
;k=&ZV
/** yU{Q`6u T
* @return <NYf !bx
* Returns the currentPage. 0DB8[#i%:
*/ (>R
publicint getCurrentPage(){ h3`\L4b
return currentPage; l} =@9A@
} v\3
\n3[u
,8`CsY^1
/** ;S5J"1)O~
* @param currentPage MV?#g-5
* The currentPage to set. SqosJ}K
*/ %S$+3q%F
publicvoid setCurrentPage(int currentPage){ I;g>r8N-Bu
this.currentPage = currentPage; DmA~Vj!a^y
} N+9W2n
?s-Z3{k
/** 5{Oq* |
* @return wR%F>[6.{
* Returns the everyPage. DCheG7lo{
*/ s$wIL//=
publicint getEveryPage(){ }HKt{k&$
return everyPage; Mjj5~by:
} Pl\r|gS;
QUO'{;,
/** Yf?hl
* @param everyPage 51Q m2,P1^
* The everyPage to set. Q|7$SS6$
*/ ?lPyapA]
publicvoid setEveryPage(int everyPage){ 8JFvz(SK>
this.everyPage = everyPage; 4/?@ %
} ecsQshR
Re<@.d
/** |6O7_U#q
* @return k5@PZFV
* Returns the hasNextPage. h0oe'Xov
*/ b9Mp@I7Q-
publicboolean getHasNextPage(){ r^v1_u,1I
return hasNextPage; oO4hBM([
} :?P>))vT%
[q!/YL3%
/** Gpf9uj%
* @param hasNextPage {~"fq.h!M
* The hasNextPage to set. Q`m9I
*/ xa[)fk$6
publicvoid setHasNextPage(boolean hasNextPage){ _C54l
this.hasNextPage = hasNextPage; !Pc&Sg
} Wi+}qO
F^Y%Q(Dd7w
/** @QO^3%b8
* @return eD,'M
* Returns the hasPrePage. o6/"IIso3
*/ <5]ufv
publicboolean getHasPrePage(){ gjL+8Rk
return hasPrePage; 0CpE,gg
} wec_=EqK0
rX}FhBl5
/** vs%d}]v
* @param hasPrePage %}}?Y`/W)
* The hasPrePage to set. x+8%4]u`
*/ p~3 (nk<+
publicvoid setHasPrePage(boolean hasPrePage){ C7=N`s}
this.hasPrePage = hasPrePage;
qHl>d*IZ
} r]=Z :
=oT4!OUf
/** &hcD/*_Z
* @return Returns the totalPage. ;Qi0j<dXd
* <
UD90}
*/ re)7h$f}
publicint getTotalPage(){ E"zC6iYZ;
return totalPage; QJF_ "
} "DC L
Z
JI[{n~bhGD
/** D%*Ryg
* @param totalPage p|>m 2(|
* The totalPage to set. !Bv.@~
*/ HJ_8 `( '
publicvoid setTotalPage(int totalPage){ ~5>k_\G8
this.totalPage = totalPage; ]NyN@9u@(
} -)Hc^'.
6&;h+;h
} &)izh) FA
RpwDOG
<<PXh&wu0
L0;XzZS
#Q"04'g
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 D]twid~OS
g=$nNQ
\6=
个PageUtil,负责对Page对象进行构造: u&Yd+');
java代码: *Ksk1T+>
kjF4c6v
*RmD%[f
/*Created on 2005-4-14*/ R0urt
package org.flyware.util.page; CT/>x3o
fRjp(m
import org.apache.commons.logging.Log; AO,^v+$
import org.apache.commons.logging.LogFactory; v ty:@?3\
.cz7jD
/** wUfm)Q#
* @author Joa B9wQ;[gQB
* @D$ogU,#
*/ ?_d3|]N
publicclass PageUtil { hd W7Qck "
6a704l%#hb
privatestaticfinal Log logger = LogFactory.getLog E
BSjU8
nG%<n
(PageUtil.class); Z>[n~{-,p
0|kH0c,T-
/** 8p#V4liE
* Use the origin page to create a new page E.,
* @param page BP@V:z
* @param totalRecords 0jt@|3
* @return dKY#Tl]
*/ ?e\u_3-9
publicstatic Page createPage(Page page, int ]:}7-;$V
iD<}r?Z
totalRecords){ %@8#+#@J0
return createPage(page.getEveryPage(), C@g/{?\
q|
UO]V
page.getCurrentPage(), totalRecords); ]*D~>q"#\
} 3G'cDemc
oA8A
@,-L
/** h!`KX2~
* the basic page utils not including exception yQ!keGj
N|%X/UjZ2.
handler `7oYXk
* @param everyPage /m4Y87
* @param currentPage l{Et:W%|
* @param totalRecords +F~B"a
* @return page :kC*<f\
*/ !+DhH2;)F
publicstatic Page createPage(int everyPage, int o(C;;C(*{
LfJMSscfv
currentPage, int totalRecords){ S0ReT*I
everyPage = getEveryPage(everyPage); OVE?;x>n/1
currentPage = getCurrentPage(currentPage); |xT'+~u
int beginIndex = getBeginIndex(everyPage, ?7"v~d]>
w,j;XPp
currentPage); ,hZ?]P&
int totalPage = getTotalPage(everyPage, y(O~=S+<
wScr:o+K>L
totalRecords); wEw;],ur
boolean hasNextPage = hasNextPage(currentPage, yH9&HFDp
-XnOj2
totalPage); 4?]s%2U6
boolean hasPrePage = hasPrePage(currentPage); -wVuM.n(Z
eh8lPTKil
returnnew Page(hasPrePage, hasNextPage, Lj/
everyPage, totalPage, (C.aQ)|T
currentPage, Fzt7@VNxc
$-.*8*9
beginIndex); 4ves|pLET
}
e'p"gX
&_-3>8gU
privatestaticint getEveryPage(int everyPage){ Sbeq%Iwm.
return everyPage == 0 ? 10 : everyPage; CdMV(
} Zy|u5J
f ~bgZ
privatestaticint getCurrentPage(int currentPage){ P0RtS1A
return currentPage == 0 ? 1 : currentPage; >Bu_NoM
} wxN&k$`a
S4rm K&
privatestaticint getBeginIndex(int everyPage, int DQ&\k'"\
R+2~%|{d
currentPage){ ],{M``]q
return(currentPage - 1) * everyPage; 24sQon
} WXG0Z
s#(7D3Pr#
privatestaticint getTotalPage(int everyPage, int L* ScSxw
p.H`lbVY
totalRecords){ IJC]Al,df
int totalPage = 0; o6:@j#b
%-BwK
if(totalRecords % everyPage == 0) aimf,(+
totalPage = totalRecords / everyPage; CAmIwAx6;
else ff=RKKnN
totalPage = totalRecords / everyPage + 1 ; k5*Z@a
A|GsbRuy
return totalPage; ,c
0]r;u!
} 5bd4]1gj
HZjuL.Tj
privatestaticboolean hasPrePage(int currentPage){ `R!2N4|;
return currentPage == 1 ? false : true; FEX67A8/;
} ;9q$eK%d
/O`R9+;
privatestaticboolean hasNextPage(int currentPage, @Fzw_qr
M
Wys$#pJ
int totalPage){ #4!f/dWJp
return currentPage == totalPage || totalPage == l<'}`
$`R=Q
0 ? false : true; U[:=7UABU?
} +{}p(9w@
%Aa_Bumf*:
)6eFYt%c
} K92M9=>
@, AB2D
rv<qze;?|
Kzy9i/bL
tK
`A_hC
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 R]RLy#j
SR`A]EC(V
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 6q7jI
)l
s@Loax6@B
做法如下: /iJsa&W}
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 vl?fCO
54/ZGaonz
的信息,和一个结果集List: j^eMi
java代码: kBY#=e).
|tz{Es<`B
_X@ Q`d
/*Created on 2005-6-13*/ :9(w~bB9$
package com.adt.bo; _@VKWU$$
&B++ "f
import java.util.List; db}lN
&vIj(e9Y
import org.flyware.util.page.Page; >5zD0!bA
"{d[V(lE"
/** [4@@b"H
* @author Joa 8ZJ6~~h
*/ Z=<D`
publicclass Result { K6@ %@v
FI)0.p
private Page page; !!mGsgnW
F5M{`:/
private List content; yVJ)JhV
%o`Cp64`Q
/** #qJ6iA6{
* The default constructor 6Q&i=!fQ
*/ &4)PW\ioY
public Result(){ 0UGAc]!/RZ
super(); 238z'I+$G/
} VTi;y{
@&9<)1F
/** 84s:cO
* The constructor using fields 2P{! n#"
* \lyHQ-gWhc
* @param page = N:5#A
* @param content . TNJuuO
*/ Zc*#LsQh.`
public Result(Page page, List content){ E~8J<gE
this.page = page; $N|Spp0
this.content = content; Jq+@%#G
} @[n%q.|VB
EJJ&`,q
/** B*^QTJ
* @return Returns the content. L:jv%;DM
*/ F$9+WS`c
publicList getContent(){ 2%MS$Fto
return content; |Z$)t%'
} qSaCl6[Do
tMo=q7ig
/** APU~y5vG (
* @return Returns the page. pvRa
*/ s&DAO r!i
public Page getPage(){ dQ#oY|a
return page; H{_6e6`e.
} lg
1r]
u:,B&}j
/** :%U
lNk
* @param content 0.1?hb|p5T
* The content to set. 6*I=%
H|
*/ t3!~=U
public void setContent(List content){ nzU0=w}V
this.content = content; 59?$9}ob
} HLh]*tQG
lvUWs
/** ESe$6)P
* @param page KnK\X>:
* The page to set. C4|79UG>s
*/ j"&Oa&SH
publicvoid setPage(Page page){ 8{Vt8>4
this.page = page; 9v7}[`^
} 3p'(E\VJ
} AQc9@3T~Bi
:r&4/sN}<
V<d`.9*}
'jKCAU5/0;
|;YDRI
2. 编写业务逻辑接口,并实现它(UserManager, +V#dJ[,8;.
/ 6DW+!
UserManagerImpl) %y)LBSxf
java代码: n5*m x7
ZPHatC
y"zZ9HQM
/*Created on 2005-7-15*/ G52z5-=v
package com.adt.service; ]YB,K)WQ
X\BdN Hr
import net.sf.hibernate.HibernateException; % "ZC9uq?
6{ pg^K
import org.flyware.util.page.Page; jYW-}2L
2JHV*/Q
import com.adt.bo.Result; a3:1`c/~\
D5!I{hp"
/** |(9l_e|
* @author Joa Q*/jQC
*/ 5"Y:^_8
publicinterface UserManager { `QT9W-0e^
o7yvXrpG(U
public Result listUser(Page page)throws ~VPE9D@
P_M!h~
HibernateException; Lvn+EM
N$cAX^~
} q)tNH/
S#\Cyn2(t
:A,7D(H|
I&5cUj{GX-
SFRYX,0m
java代码: kX:8sbZ##4
,go$6
f5.Be%
/*Created on 2005-7-15*/ Vv>hr+e
package com.adt.service.impl; *(nu0
Bo/i =/7%
import java.util.List; 8ya|eJ]/L
?lIh&C8]X
import net.sf.hibernate.HibernateException; 1xsB@D
4& 9V
import org.flyware.util.page.Page; EL9JM}%0v
import org.flyware.util.page.PageUtil; TZ PUVOtL_
B)Dsen
import com.adt.bo.Result; (KT+7j0^
import com.adt.dao.UserDAO; =5g|7grQ:`
import com.adt.exception.ObjectNotFoundException; tU>4?`)E
import com.adt.service.UserManager;
=#vU$~a
N gOc2I
/** Vc
"+|^
* @author Joa - 4S4I
*/ zHvW@A'F
publicclass UserManagerImpl implements UserManager { 7*47mJyc
}kk[lvhJ
private UserDAO userDAO; N!13QI
H
`W4Is~VVv
/** m>'#664q1
* @param userDAO The userDAO to set. V_T~5%9Fy
*/ oh >0}Gc8
publicvoid setUserDAO(UserDAO userDAO){ *BQy$dfE
this.userDAO = userDAO; Aj@t*3
} _;G|3>5u
IHe?/oUL"b
/* (non-Javadoc) *GM.2``e
* @see com.adt.service.UserManager#listUser \B8[UZA.&
|f+fG=a67V
(org.flyware.util.page.Page) =M34
HPG
*/ Qh4Z{c@
public Result listUser(Page page)throws ^+9i~PjL
'tq4-11xB
HibernateException, ObjectNotFoundException { AXpyia7nU
int totalRecords = userDAO.getUserCount(); P? LpI`f
if(totalRecords == 0) .OD{^Kq2
throw new ObjectNotFoundException 4% 2MY\
dxF)) Z
("userNotExist"); 6Xt c3
page = PageUtil.createPage(page, totalRecords); $`Aps7A
List users = userDAO.getUserByPage(page); 2QV|NQSl
returnnew Result(page, users); / U"3LX
} !Bb^M3iA
ngH_p>
} S{qsq\X
r1|;V~a$~
6 kAXE\T
s!/Q>A
s C?-L
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \v([,tiW%
/@K1"/fqH
询,接下来编写UserDAO的代码: o,=dm@j
3. UserDAO 和 UserDAOImpl: I>spJ5ls
java代码: )dI `yf
e}W|wJ):j@
MrpT5|t
/*Created on 2005-7-15*/ 76EMS?e
package com.adt.dao; x5W.
3*
!a9/8U_>XF
import java.util.List; >66v+
>/DlxYG?
import org.flyware.util.page.Page; IVSd,AR7yY
YW^sf,zQ
import net.sf.hibernate.HibernateException; %ZJ;>a#
~.8p8\H
/** 1Ozy;;\-9
* @author Joa LT)G"U~
*/ ]08
~"p
publicinterface UserDAO extends BaseDAO {
:O{
ZZ
|ea}+N
publicList getUserByName(String name)throws Cb;49;q
*`bAu *
HibernateException; zgA/B{DaC;
bJ9K!6s??`
publicint getUserCount()throws HibernateException; 3 3b 3v\N
O4Hc"v
publicList getUserByPage(Page page)throws NEX{vZkgw
#Ue_
HibernateException; ]jwF[D
UU]a).rz
} w:o,mzuXK
vrvOPLiQ
f;%\4TH?
DsF<P@O6
ffS]%qa
java代码: R3@$ao
!;;WS~no3
0^&-j.9
/*Created on 2005-7-15*/ L:RMZp*bK
package com.adt.dao.impl; G,h=5y9_J
^`oyf{w@
import java.util.List; .wz.Jr`{
nn6&`$(Q~
import org.flyware.util.page.Page; Cw&U*H
Tjza3M
import net.sf.hibernate.HibernateException; >TZyax<:
import net.sf.hibernate.Query; = $awUy
g:CMIe4
import com.adt.dao.UserDAO; RS[>7-9
m8<l2O=m
/** Kq2,J&Ca3
* @author Joa ^%k[YJtB=i
*/ KcNh3CR
public class UserDAOImpl extends BaseDAOHibernateImpl U<mFwJ C]
k\wI^D
implements UserDAO { e`Vb.E)
uO;_T/^u
/* (non-Javadoc) T_*R^Ukb5
* @see com.adt.dao.UserDAO#getUserByName $oU40HA)W]
OMVK\_oXo
(java.lang.String) UFY_.N~
*/ 7Q3a0`Iq
publicList getUserByName(String name)throws Fb9!x/$tGV
7! "OF
HibernateException { !`?*zf
String querySentence = "FROM user in class 6l-V%3-
*T{P^q.s~[
com.adt.po.User WHERE user.name=:name"; o$+"{3svw?
Query query = getSession().createQuery x*2' I
!/Wp0E'A
(querySentence); 6Cd% @Q2cr
query.setParameter("name", name); %>Y86>mVz
return query.list(); ]S#m
o
} h#!u"'JW
~]&,v|g&
/* (non-Javadoc) l
d4#jV ei
* @see com.adt.dao.UserDAO#getUserCount() -<Zs7(
*/ S 8$kxQg
publicint getUserCount()throws HibernateException { p?,:
int count = 0; R#UcwX}o
String querySentence = "SELECT count(*) FROM fd}
Ul
|T@\-8Ok
user in class com.adt.po.User"; (:2,Rr1"
Query query = getSession().createQuery 1JXa/f+
Q]d3a+dK
(querySentence); J}UG{RttI
count = ((Integer)query.iterate().next _@Le MNv
{(,[
()).intValue(); JD}"_,-
return count; l.Qv9Ll|b
} %d/Pc4gfc
pk0Cx
/* (non-Javadoc) HKZD*E((
* @see com.adt.dao.UserDAO#getUserByPage 7$&3(#!N
N?mTAF'M
(org.flyware.util.page.Page) o<r|YRzQl
*/ kxp, ZP
publicList getUserByPage(Page page)throws g1s\6%g
b;XUv4~V
HibernateException { *.]M1
String querySentence = "FROM user in class b7_uT`<
>uN)O-
com.adt.po.User"; rG*Zp7{
Query query = getSession().createQuery Y}pCBw
mgxoM|n6
(querySentence); ufekhj
query.setFirstResult(page.getBeginIndex()) 7jL3mI;n%;
.setMaxResults(page.getEveryPage()); DlWnz-
return query.list(); ]d|:&h
} bEJz>oyW"
xbv
} M{ mdh\
QXcSDJ
Gcseq
"/&_B
|*+f N8
至此,一个完整的分页程序完成。前台的只需要调用 2HemPth
,@1.&!F4it
userManager.listUser(page)即可得到一个Page对象和结果集对象 X <<hb
D<
h+r?
的综合体,而传入的参数page对象则可以由前台传入,如果用 hS}d vZa
}I1SC7gY
webwork,甚至可以直接在配置文件中指定。 }Ra'`;D$
1k
*gbXb
下面给出一个webwork调用示例: Uz`K#Bz
java代码: N BUSr}8|
_*I@ J/
Gw5j6
/*Created on 2005-6-17*/ _*SA_.0
package com.adt.action.user; Gw/imXL
m.}Yn,
import java.util.List; 5g{F-
:bhpYEUMx
import org.apache.commons.logging.Log; ^K#PcPF-j
import org.apache.commons.logging.LogFactory; t'@qb~sf
import org.flyware.util.page.Page; !u0qF!/W
lo%:$2*'p
import com.adt.bo.Result; nK"XyZ&
import com.adt.service.UserService; 5zqlK-$
import com.opensymphony.xwork.Action; X(Wd
vIi#M0@N
/** ]}~[2k.
* @author Joa H~IN<3ko
*/ 2$g3ABfV
publicclass ListUser implementsAction{ cnUYhxE+s
4\.1phe$a
privatestaticfinal Log logger = LogFactory.getLog
YtzB/q8I
/"Bm1
(ListUser.class); K9#=@}!3L
5f:Mb|.?
private UserService userService; 8KQ]3Z9p
y3]7^+k
private Page page; u7oHqo`
X_}2xo|T
privateList users; I?l%RdGW
uK:?6>H
/* =lzRx%tm
* (non-Javadoc)
f:_\S
* TfD]`v`]
* @see com.opensymphony.xwork.Action#execute() B} %B4&Ij
*/
$rAHtr
publicString execute()throwsException{ XF`,mV4
Result result = userService.listUser(page); 7g}lg8M
page = result.getPage(); '8Q:}{
users = result.getContent(); 1kG{z;9
return SUCCESS; |hp_<F9.
} 'Y
ZYRFWXM
FY^[?lj
/** dU7+rc2,CU
* @return Returns the page. (QPfrR=J4
*/ BrdHTk= Vy
public Page getPage(){ Ye '=F
return page; .#M'
} #bqc}h9
l Ikh4T6i
/** kjo,?$r
%
* @return Returns the users. _%M5
T
*/ 7fVlA "x
publicList getUsers(){ hP=^JH
return users; 6^vMJ82U
} JF%eC}[d
7r`A6 \
!
/** D;pfogK @
* @param page gy
Jx>i
* The page to set. 5AvbKT
*/ YceX)
publicvoid setPage(Page page){ :N \j@yJK
this.page = page; U#I8Rd I,
} p7UdZOi2
`aj;FrF
/** 7X
h'VOljB
* @param users Op&i6V}<s
* The users to set. h&$7^P
*/ td:GZ %
publicvoid setUsers(List users){ }tvLe3O
this.users = users; l\PDou@5
} j4ARGkK5B
qUH02"z@9
/** bbDl?m&bq
* @param userService GOT@
* The userService to set. (v11;k dJB
*/ z|w@eQ",
publicvoid setUserService(UserService userService){ p;[">["
this.userService = userService; xWw Qm'I2}
} Hm>M}MF3
} Z/#&c
v99gI%TA'
P}] xz Vy
HN/ %(y
v"y0D
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 0b)^#+
FT*OF 3
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ,_STt)
{XT3M{`rWL
么只需要: &n_aMZ;
java代码: -^C't_Q o
6TN!63{Cz
^BDM'
<?xml version="1.0"?> a
J%&Y5L
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork %?GLMf7)
g"Eg=CU
1.0//EN" "http://www.opensymphony.com/xwork/xwork- -dCM
eC
3 34UMH__
1.0.dtd"> ~]}V"O%,
0q|.]:][Eo
<xwork> Fap@cW3?8
:xn/9y+s
<package name="user" extends="webwork- S7{L-"D=y
~FnB!Mh}?
interceptors"> ^
:%"Z&
-Wp69DP6q
<!-- The default interceptor stack name K4]42#
Rgb1B3gu
--> wA@y B"
<default-interceptor-ref H3$~S '
"A_,Ga
name="myDefaultWebStack"/> ]2^tV.^S^
e,Ih7-=Er,
<action name="listUser" + 9vd(c
c6IFt4)g
class="com.adt.action.user.ListUser"> h5+qP"n!?q
<param !1i(6 ?~#4
9}~WwmC|x
name="page.everyPage">10</param> @x9DV{j)V
<result }(x|
']nB_x7
name="success">/user/user_list.jsp</result> ``%uq)G=D
</action> W<J".2D
aBo8?VV]8
</package> ]_cBd)3P}
YeN /J.R
</xwork> Ix+===6
Y^zL}@
G k'j<a
<SiD m-=E
SfKm]Z>Hp
d>ltL`xn
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 %9|}H [x
p&B
c<+3e
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。 jft%\sY
e-$U .cx
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %+PWcCmn
J.
]~J|K
:K%{?y
P3w]PG@
2C9wOO
我写的一个用于分页的类,用了泛型了,hoho tBDaFB
q#fj?`k
java代码: ]dZ8]I<$C
$"P9I-\m
x/nlIoT
package com.intokr.util; ,vfi]_PK
U) tqo_
import java.util.List; g+5{&YD
zzf;3S?
/** Y{].%xM5
* 用于分页的类<br> {`Ekv/XWa
* 可以用于传递查询的结果也可以用于传送查询的参数<br> yY,O=yOjq
* ("2ukHc
* @version 0.01 H*#L~!]
* @author cheng @"M%ZnFu
*/ :HSqa9>wa
public class Paginator<E> { BMw_F)hTO
privateint count = 0; // 总记录数 sE*A,z?
privateint p = 1; // 页编号 ENlqoj1
privateint num = 20; // 每页的记录数 X#l]%IrW!
privateList<E> results = null; // 结果 T6s~f$G
8no_xFA
/** 1WGcv O)<
* 结果总数 kcy?;b;z
*/ &^ECQ
publicint getCount(){ X[L6Av
return count; ISHNeO8
} |ITSd%`3_
5):2;h k
publicvoid setCount(int count){ l_ycYD$ZA
this.count = count; O34'c_ fZ
} AJ'YkSg
R[eQ}7;+
/** l3Vw?f
* 本结果所在的页码,从1开始 8 *@knkJ
* s1,kTde
* @return Returns the pageNo. zWiMl.[
*/ fo63H'7
publicint getP(){ =^.f)
return p; nSH
A,c
} [al, UO
#"}Z'|X*
/** s:
c
* if(p<=0) p=1 >|<8QomD
* 9>qc 1z
* @param p */gm! :Ym
*/ DAs&4Y`
publicvoid setP(int p){ 2ql7*g?Uq@
if(p <= 0) +PC<#
p = 1; 4:$?u}9[:[
this.p = p; :3qA7D }
} &1hJ?uM01
$y!k)"k
/** NB]T~_?]*
* 每页记录数量 ^%X,Rml<e
*/ RX",Zt$q
publicint getNum(){ \~H;Wt5
return num; 3VJoH4E!6
} i2or/(u`
]?P9M<0PM
/** x)6yWr[ri%
* if(num<1) num=1 te?R(&
*/ @kR/=EfS
publicvoid setNum(int num){ M[5zn
if(num < 1) <y${Pkrj
num = 1; ien >Ou
this.num = num; @:$zReS2
} |CME:;{T
*&X.
/** #4h_(Y
* 获得总页数 !:Lb^C;/
*/ 1x+YgL5
publicint getPageNum(){ uMm/$#E
return(count - 1) / num + 1; \A`pF'50
} (>m3WI$d
-a`EL]NX
/** /p~Wk4'
* 获得本页的开始编号,为 (p-1)*num+1 8" Z!: =A
*/
jKV,i?
publicint getStart(){ [3`T/Wm
return(p - 1) * num + 1; ]a|3"DP5
} V}732?Jy
G!~[+B
/** <wwcPe}
* @return Returns the results. 3 wVN:g7
*/ %
R~9qO
publicList<E> getResults(){ jREj]V>
return results; 9NwA5TP9_
} ZVotIQ/Q'
v#/Uq?us
public void setResults(List<E> results){ 9WQC\/w
this.results = results; E?|"?R,,,
} 5#JGNxO
DKL< "#.7
public String toString(){ J&~nD(&TY
StringBuilder buff = new StringBuilder eWO^n>Y
|Ia3b VW
(); _%Ay\4H^\
buff.append("{"); kvh}{@|-
buff.append("count:").append(count); ^.Y"<oZSS
buff.append(",p:").append(p); >LxYP7M
buff.append(",nump:").append(num); jqHg'Fq
buff.append(",results:").append X#mm
Z;P
Z(AI]wk3<
(results); 11}fPWK
buff.append("}"); .?b2Bd!MC
return buff.toString(); .fxI)
} CQfrAk4mu
-ecP@,
} 6L~@jg~0A[
\RZFq<6>
\ief [