Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]GS bjHsO
km(Po}
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Wqnc{oq|$
Sz~OX6L
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 PnTu
+q4O D$}
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 [^)g%|W
OI*H,Z"
。
G*m0\
dr(*T
分页支持类: m 5.Zu.
v19-./H^
j
java代码: ]'cs.
gR**@t=;j
=l6mL+C
package com.javaeye.common.util; #E?4E1bnB
%>yL1BeA4
import java.util.List; >?b!QU*a
#WuBL_nZ~
publicclass PaginationSupport { u,
ff>/1
s7<AfaJPF
publicfinalstaticint PAGESIZE = 30; #spCtZE
| Iib|HQ)
privateint pageSize = PAGESIZE; ^~dWU>
]d]]'Hk
privateList items; dM5-;
Q8NX)R
privateint totalCount; e(sk[guvX
4Ig;3 ^%71
privateint[] indexes = newint[0]; 7/H)Az@i45
uH]OEz\H'
privateint startIndex = 0; _w{Qtj~s|
!VJoM,b8
public PaginationSupport(List items, int pRqx`5 }
ixFi{_
totalCount){ .8R@2c`}Cs
setPageSize(PAGESIZE); m*pJBZxd
setTotalCount(totalCount); NUZl`fu1Z4
setItems(items); 6<]lW
setStartIndex(0);
2iOV/=+
} M+>u/fldV
3Ul*QN{6
public PaginationSupport(List items, int S!UaH>Rh
3<!7>]A
totalCount, int startIndex){ n]9$:aLZ
setPageSize(PAGESIZE); ]'}L 1r
setTotalCount(totalCount); )UR7i8]!0
setItems(items); QY/w
setStartIndex(startIndex); E.TAbD&5(
} ,2q-D&)\Z
&HW9Jn
public PaginationSupport(List items, int O?2DQY?jT
tc! #wd+u
totalCount, int pageSize, int startIndex){ uYN`:b8
setPageSize(pageSize); WLT"ji0w2
setTotalCount(totalCount); *VcJ= b
2Y
setItems(items); *p U x8yB
setStartIndex(startIndex); ~ a:
} vQCy\Gi
Pal=F0-Q\
publicList getItems(){ &pRREu:[4L
return items; %Zi} MPx
} $I=~S[p
WE?5ehEme
publicvoid setItems(List items){ ]/Pn
EU[
this.items = items; fex@,I&
} f8~_E
W4S,6(
publicint getPageSize(){ <YY 14p
return pageSize; >Ry01G]_/h
} $mI Loy
B,
!zo{tI19
publicvoid setPageSize(int pageSize){ ! mHO$bQ"
this.pageSize = pageSize; CrLrw T
} 5+'<R8{:,
GJrG~T
publicint getTotalCount(){ :>
'+"M2r
return totalCount; ;I}fBZ3
} b9krOe*j
dH!*!r>
publicvoid setTotalCount(int totalCount){ 6Oq7#3]
if(totalCount > 0){ UNYqft4
this.totalCount = totalCount; "sTRS*
int count = totalCount / mt
.sucT
@]j1:PN-
pageSize; lN@o2QX
if(totalCount % pageSize > 0) ^c|/*u
count++; iTwm3V
P
indexes = newint[count]; ;pAK_>
for(int i = 0; i < count; i++){ GOPfXtkC
indexes = pageSize * ;p//QJB9
LoV<:|GTI
i; jp,4h4C^)
} K0~rN.C!0
}else{ jd:6:Fm
this.totalCount = 0; R&&4y 7
} A^g(k5M*
} Nb\4 /;#
F5<Hm_\:
publicint[] getIndexes(){ V0@=^Bls
return indexes; LV Ge]lD
} }#fbbtd
]M=&+c>H~
publicvoid setIndexes(int[] indexes){ aN?zmkPpov
this.indexes = indexes; /:
"1Z]@
} <)9y{J}s:
)`:UP~)H
publicint getStartIndex(){ ]Ze1s02(
return startIndex; \e*]Ls#jS
} 0kh6@y3
M%HU4pTW#o
publicvoid setStartIndex(int startIndex){ I9Xuok!0>=
if(totalCount <= 0) ye&;(30Oq
this.startIndex = 0; nlP;nl W
elseif(startIndex >= totalCount) ~ljXzD93Z
this.startIndex = indexes 0J9x9j`&j
P:c w|Q
[indexes.length - 1]; M3\AY30L
elseif(startIndex < 0) 54T`OE
=
this.startIndex = 0; /m1\ iM\
else{ uRvP hkqm
this.startIndex = indexes ';CNGv -
0mE 0 j
[startIndex / pageSize]; @gblW*Zhk
} 4(+PD&_J
} %b$>qW\*&
Et$2Y-L.
publicint getNextIndex(){ ^8WRqQdx
int nextIndex = getStartIndex() + t.<i:#rj>l
4?kcv59
pageSize; ^#pEPVkY
if(nextIndex >= totalCount) Wr
4,YQM
return getStartIndex(); XFl6M~ c
else }bxs]?OW>
return nextIndex; c 9Mz]1@f
} {: /}NpA$
Txu/{M,
publicint getPreviousIndex(){ 6K^#?Bn;
int previousIndex = getStartIndex() - Dt@SqX:~Ee
Nn6%9PX_)
pageSize; kiEa<-]
if(previousIndex < 0) w)f#V s
return0; :#Wd~~d
else )=+|i3]U
return previousIndex; 5pX6t
} i-1op> Y
&C}*w2]0S
} =_CzH(=f#
-).C
)0`C@um
hN_]6,<\
抽象业务类 X|dlt{Gf
java代码: &oNAv-m^GD
Rq -ZL{LR7
pglVR </
/** E.h*g8bXe
* Created on 2005-7-12 0GwR~Z}Z
*/ 6tZI["\
package com.javaeye.common.business; CIWO7bS
!
nx{
X
import java.io.Serializable; 0GL M(JmK
import java.util.List; ~%oR[B7=|
Eci\a]
import org.hibernate.Criteria; @7}W=HB
import org.hibernate.HibernateException; >P(.:_^p
import org.hibernate.Session; Uo49*Mr
import org.hibernate.criterion.DetachedCriteria; h[ ZN+M
import org.hibernate.criterion.Projections; Py<}S-:
import gGYKEq{j(
+`4A$#$+y
org.springframework.orm.hibernate3.HibernateCallback; lE;!TQj:X
import bA 2pbjg=
@ Qe0! (_=
org.springframework.orm.hibernate3.support.HibernateDaoS btB%[]
9c],<;{'
upport; 637:
oT_`O
ZSw.U:ep$s
import com.javaeye.common.util.PaginationSupport; 'u658Tj
Om&Dw|xG8
public abstract class AbstractManager extends /Oono6j
vO=fP_
HibernateDaoSupport { cQ|NJ_F{1
4-w{BZuS
privateboolean cacheQueries = false; ZCw]m#lS
e20-h3h+
privateString queryCacheRegion; $G>. \t
]:;&1h3'7
publicvoid setCacheQueries(boolean buC{r,
$b\P|#A
cacheQueries){ x-c"%Z|
this.cacheQueries = cacheQueries; bt *k.=p
} =1!
'QUc
_F{C\}
publicvoid setQueryCacheRegion(String ~&O%N
reVgqYp{{-
queryCacheRegion){ }JfjX'
this.queryCacheRegion = ?2a $*(
/reX{Y
queryCacheRegion; u2I Cl
} BUFv|z+H
Efe 7gE'
publicvoid save(finalObject entity){ & kIFcd@
getHibernateTemplate().save(entity); iLT}oKF2N;
} 9mgIUjz
^Cmyx3O^
publicvoid persist(finalObject entity){ 9Flb|G%
getHibernateTemplate().save(entity); H]s.=.Ki
}
)jj0^f1!j
J,G
lIv.A
publicvoid update(finalObject entity){ 8t`?#8D}
getHibernateTemplate().update(entity); 0x7'^Z>-oe
} $kgVa^
NA*#~
publicvoid delete(finalObject entity){ V]&\fk-{
getHibernateTemplate().delete(entity); R]dg_Da
} ^aQ"E9
l:%GH
publicObject load(finalClass entity, 0YzpZW"+
fM}#ON>Z
finalSerializable id){ =;k|*Ny
return getHibernateTemplate().load neh(<>
"b[5]Y{
U
(entity, id); l,
wp4Ll
} !wNO8;(
l2d{ 73h
publicObject get(finalClass entity, ToQ"Iy?
u-TUuP
finalSerializable id){ iE{&*.q_}>
return getHibernateTemplate().get ,Q,^3*HX9}
Q?T]MUY(L
(entity, id);
OSJ$d
} U.TA^S]`g
Al'3?
publicList findAll(finalClass entity){ ZuIefMiG~+
return getHibernateTemplate().find("from ^{{ qV
O f#:
" + entity.getName()); X8|EHb<
} %SI'BJ
4YHY7J
publicList findByNamedQuery(finalString K^$=dLp
':W[ A
namedQuery){ tDo"K3
return getHibernateTemplate fnY.ao1-s[
+#By*;BJ
().findByNamedQuery(namedQuery); vy/-wP|1
} h~26WLf.
N7_"H>O$0U
publicList findByNamedQuery(finalString query, S$3JMFA
:KN-F86i
finalObject parameter){
7.T?#;'3
return getHibernateTemplate C?Ucu]cW
nm+s{
().findByNamedQuery(query, parameter); G`zm@QL
} .2pK.$.
Ah<+y\C
publicList findByNamedQuery(finalString query, Tr|JYLwF
FqifriLN
finalObject[] parameters){ i?gSC<a
return getHibernateTemplate q =Il|Nb>
H[UlY?&+
().findByNamedQuery(query, parameters); 2Hdu:"j
} ]d`VT)~vje
!+ njS
publicList find(finalString query){ DJ%PWlK5
return getHibernateTemplate().find |' .
uocGbi:V';
(query); kl,3IKHa
} W`&hp6Jq
L(o15
publicList find(finalString query, finalObject 6,uX,X5
?8 {"x8W;
parameter){ m3ff;,
return getHibernateTemplate().find 4sM.C9W
4~=l}H>&
(query, parameter); 0ksa
} ?}7p"3j'z
-F92 -jBM4
public PaginationSupport findPageByCriteria ;wVwX6:ZKr
T Ge_G_'o
(final DetachedCriteria detachedCriteria){ SzRmF1<
return findPageByCriteria ? q&T$8zc4
GF
WA>5n'
(detachedCriteria, PaginationSupport.PAGESIZE, 0); p#[.{
} {PmZ9
<1%$Vq
public PaginationSupport findPageByCriteria tu?MY p;
MPk5^ua:
(final DetachedCriteria detachedCriteria, finalint rs.M]8a2{&
8V(pugJ
startIndex){ XlJZhc
return findPageByCriteria \?N2=jsu$
- YV>j
(detachedCriteria, PaginationSupport.PAGESIZE, @P"p+
G\?YK.Y>
startIndex); `lPfb[b
} ipILG4
kW (Bkuc)
public PaginationSupport findPageByCriteria j7c3(*Pl
wPl%20t
(final DetachedCriteria detachedCriteria, finalint go"Hf_
2"5v[,$1H
pageSize, d[35d J7F
finalint startIndex){ _2nx^E(pd
return(PaginationSupport) ;$tSb ~K+
sC ;+F*0g
getHibernateTemplate().execute(new HibernateCallback(){ ?s _5&j7
publicObject doInHibernate ASfaX:ke
wf$s*|z
(Session session)throws HibernateException { Dxxm="FQZ
Criteria criteria = '{`$#@a.
$kKjgQS(
detachedCriteria.getExecutableCriteria(session); T^v}mWCZ
int totalCount = >*n0n!vF
1QJL .
((Integer) criteria.setProjection(Projections.rowCount gO^gxJ'0t
=ruao'A
()).uniqueResult()).intValue(); _y>~
yZx
criteria.setProjection /=, nGk>
"vslZ`RU
(null); ~nPtlrQa#*
List items = %#}Z y
{_Gs*<.
criteria.setFirstResult(startIndex).setMaxResults B]$GSEB
<|\Lm20G]
(pageSize).list(); L:8q8i
PaginationSupport ps = IMfqiH)
)/EO&F
new PaginationSupport(items, totalCount, pageSize, 'ah[(F<*@e
\G3rX9xG
startIndex); X|8c>_}
return ps; m9A!D
} Bw{I;rW{2
}, true); -GgA&dh
} YDFyX){
(khL-F
public List findAllByCriteria(final F:l%O#V
uH-)y,2&
DetachedCriteria detachedCriteria){ BCcjK6'
return(List) getHibernateTemplate 3Hm/(C
7`YEH2
().execute(new HibernateCallback(){ lPJ\-/>$z
publicObject doInHibernate l$'wD hN*
EyLu O-5
(Session session)throws HibernateException { V/;B3t~f
Criteria criteria = .%OR3"9@
QVE6We
detachedCriteria.getExecutableCriteria(session); nQ L@hc
return criteria.list(); S[T8T|_
} Qdp)cT
}, true); IkXx# )
} s!e3|pGS
M:6"H%h,W
public int getCountByCriteria(final I0RvnMw
KK%M~Y+tU'
DetachedCriteria detachedCriteria){ TBrPf-Xr
Integer count = (Integer) Fr$5RAyg
2wgg7[tGi
getHibernateTemplate().execute(new HibernateCallback(){ V#}kwON
publicObject doInHibernate 6Kb1~jY
jb;hcraR
(Session session)throws HibernateException { r(2uu
Criteria criteria = Lu0x
(/
F*K_+
?m
detachedCriteria.getExecutableCriteria(session); _\HQvH
return 'XBFv9&
7`hP?a=
criteria.setProjection(Projections.rowCount =6#Eh=7N
IyPnp&_
()).uniqueResult(); 2,P^n4~A?w
} L z1ME(
}, true); I,'k>@w{s
return count.intValue(); Q?/o%`N
} UEVG0qF
} 63~
E#Dt4
9?3&?i2-
<V6VMYXY4
wsVV$I[2
@{pLk4E
:$9tF>
用户在web层构造查询条件detachedCriteria,和可选的 2Q"K8=s
.@Dxp]/B}
startIndex,调用业务bean的相应findByCriteria方法,返回一个 0k(a VkZ I
19KQlMO.G
PaginationSupport的实例ps。 9]wN Bd
m7>JJX3=<
ps.getItems()得到已分页好的结果集 [\b0Lem
ps.getIndexes()得到分页索引的数组 8&Y^""#e)
ps.getTotalCount()得到总结果数 M+9 gL3W
ps.getStartIndex()当前分页索引 mS~kJy_-
ps.getNextIndex()下一页索引 /_#q@r4ZQ
ps.getPreviousIndex()上一页索引 6qd\)q6T&x
QZ%`/\(!8_
qXjxNrK
Nm>A'bLM
W1FI mlXS
e01epVR;
!o[7wKrXb
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 d6sye^P
ZEO,]$Yi7
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ^Zy%fv,
^B2
-)
一下代码重构了。 klR|6u]%
fLm*1S|%\
我把原本我的做法也提供出来供大家讨论吧: |WdPE@P
3J438M.ka
首先,为了实现分页查询,我封装了一个Page类: yD6[\'%
java代码: gy9U2Wgf|
_1L![-ac
}:*]aL<7_
/*Created on 2005-4-14*/ x*&|0n.D
package org.flyware.util.page; Ziu]'#
nSAdCJ;4
/** wtV#l4
* @author Joa [o5Hl^
* A4<Uu~
*/ m&?r%x
publicclass Page { A1?2*W
;H.^i|_/
/** imply if the page has previous page */ ZH)="qx[
privateboolean hasPrePage; &&RimoIeo
0f>5(ek
/** imply if the page has next page */ }HePZ{PLM
privateboolean hasNextPage; +|89>}w4
KX7>^Bt&k
/** the number of every page */ 6,9>g0y'NG
privateint everyPage; ;<2G
4G>H
/** the total page number */ U,- 39mr
privateint totalPage; h"lv7;B$
Ev(>z-{F
/** the number of current page */ 'B0{_RaTb
privateint currentPage; Gvqxi|
TNh1hhJ$b
/** the begin index of the records by the current #PQB(=299P
BC<^a )D=
query */ V2|aN<Sx<
privateint beginIndex; [ $n_6
!|S43i&p
VsE9H]v
/** The default constructor */ sCb=5uI
public Page(){ =k0_eX0
~-J]W-n
} >R!jB]5
1sdLDw_)p
/** construct the page by everyPage
|CZ@te)>
* @param everyPage r_6ZO&
* */ Mz~D#6=
public Page(int everyPage){ 6U,O*WJ%e
this.everyPage = everyPage; dl@%`E48w
} ouFYvtF g
l
+OFw)8od
/** The whole constructor */ u=7J/!H7^
public Page(boolean hasPrePage, boolean hasNextPage, 7.#F,Ue_0T
R1GEh&U{
4X
|(5q?
int everyPage, int totalPage, os={PQRD
int currentPage, int beginIndex){ g($DdKc|g
this.hasPrePage = hasPrePage; }$Tl ?BRpU
this.hasNextPage = hasNextPage; W_8wed:b
this.everyPage = everyPage; :G2k5xD/E
this.totalPage = totalPage; 'd$P`Vw:
this.currentPage = currentPage; PFne+T!2F
this.beginIndex = beginIndex; 5BKt1%Pg
} iJ3e1w$
c+$*$|t=v`
/** C$D-Pt"+
* @return ?9\EN|O^
* Returns the beginIndex. tL)t" i
*/ 2Kyl/C,
publicint getBeginIndex(){ m?fy^>1
return beginIndex; ZR?yDgL
}
)PuFuf(wz
?>rW>U6:P
/** sN2p76KN
* @param beginIndex &NK,VB;
* The beginIndex to set. S4Ww5G?.
*/ &*G#H~\
publicvoid setBeginIndex(int beginIndex){ W=vP]x
>J
this.beginIndex = beginIndex; IrhA+)pdse
}
QPg8;O
fNt`?pWH
/** {~sDYRX
* @return ~SF<,-Kg
* Returns the currentPage. I3mGo
*/ lXiKY@R#
publicint getCurrentPage(){ P5nO78
return currentPage; N@1+O,o
} z>Hgkp8D"
1Y@Aixx
/** Qqvihd
* @param currentPage W!&'pg
* The currentPage to set. f@DYN!Z_m
*/ 48qV>Gwf
publicvoid setCurrentPage(int currentPage){ &c:Ad%
z
this.currentPage = currentPage; #( jw!d&
} sy"^?th}b
u\{ g(li-I
/** =L:4i\4
* @return 2h1C9n%j9
* Returns the everyPage. aV?@s4
*/ +hT:2TXn
publicint getEveryPage(){ )oPLl|=h
return everyPage; ruzspS
} 3?7\T#=
M)N?qRD
/** }\#Rot>Y
* @param everyPage TDNQu_E
* The everyPage to set. n3Z5t
*/ 5b[jRj6
publicvoid setEveryPage(int everyPage){ ]0)|7TV*
this.everyPage = everyPage; O8u j`G 9
} -}=%/|\FG
,:H\E|XeBw
/** m~u5kbHOi=
* @return O#k6' LN?
* Returns the hasNextPage. S=nzw-(I
*/ @zz1hU
publicboolean getHasNextPage(){ r1LViK
return hasNextPage; fhp<oe>D
} qI<mjB{3`
#=f?0UTA
/** >wBJy4:
* @param hasNextPage V=V:SlS9|
* The hasNextPage to set. M&Uj^K1
*/ ;YX4:OBqr
publicvoid setHasNextPage(boolean hasNextPage){ V<@ o<R
this.hasNextPage = hasNextPage; k"]dK,,
} *c*0PdV
_D_LgH;}
/** (+3Wgl+]/
* @return xAe~]k_D
* Returns the hasPrePage. SNE#0L'}
*/ : b~6i%b
publicboolean getHasPrePage(){ U1RpLkibQ
return hasPrePage; [uls8
"^/j
} u1PaHgi$
&c%g
/** g(J&m<I
* @param hasPrePage ,@3$X=),E
* The hasPrePage to set. rJ{O(n]j
*/ ,JN8f]a^"g
publicvoid setHasPrePage(boolean hasPrePage){ yi%-7[*]=
this.hasPrePage = hasPrePage; R Yl>
} tAte)/0C
lh D,\3/O
/** 9Fm"ei
* @return Returns the totalPage. e9[|!/./5
* 5qoSEI-m
*/ +H#U~p$
publicint getTotalPage(){ F>[,zN
return totalPage; ;Uu(zhbj
} me ks
RcF
{0^&SI"5`E
/** GF%314Xu
* @param totalPage I{:(z3
* The totalPage to set. .j>hI="b
*/ /&{$ pM|?
publicvoid setTotalPage(int totalPage){ m"jV}@agX
this.totalPage = totalPage; i?e`:}T
} $Gv9m
/BV03B
} c#]q^L\x
<_Q:'cx'
hq/k*;
MxcFvo*LCp
5N*Ux4M
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 7=OQ8IM!
H4!+q:<
个PageUtil,负责对Page对象进行构造: /E5 5Pec
java代码: ~\3kx]^10
Z(_ZAB%+D
*`Yv.=cd
/*Created on 2005-4-14*/ ;cz|ss=
package org.flyware.util.page; Ox'/`Mppw
>P $;79<
import org.apache.commons.logging.Log; /<8N\_wh
import org.apache.commons.logging.LogFactory; `zt_7MD
Vy,^)]
/** ;~u{56
* @author Joa pBP.x#|
* (%o2jroQ#
*/ 0`A~HH}
publicclass PageUtil { X2i}vjkY
BQ2wnGc
privatestaticfinal Log logger = LogFactory.getLog BC;:
,b;{emX h
(PageUtil.class); { e5/+W
tP%{P"g3^
/** -cm$[,b6
* Use the origin page to create a new page g{9+O7q
* @param page -,{-bi
* @param totalRecords j>/ ,$H
* @return U Gpu\TB
*/ x5WW--YR+
publicstatic Page createPage(Page page, int 4[-*~C|W5
p6XtTx
totalRecords){ fb:j%1WF
return createPage(page.getEveryPage(), /q$,'^.A
(?! ,p^
page.getCurrentPage(), totalRecords); "a/ Q%.P
} u@%r
~ Yngkt
/** I1>N4R-j
* the basic page utils not including exception ^T,Gu-2>
H'UR8%
handler T,OwM\`.X{
* @param everyPage Uyr3dN%*r
* @param currentPage fiN3xP]V
* @param totalRecords d/e|'MPX
* @return page LJTQaItdqJ
*/ d{de6 `
publicstatic Page createPage(int everyPage, int I]y.8~xs
AkT<2H|4
currentPage, int totalRecords){ }Lw>I94e
everyPage = getEveryPage(everyPage); 5rV((
currentPage = getCurrentPage(currentPage); l?)ZJ3]a
int beginIndex = getBeginIndex(everyPage, H7kPM[
A?T<",bO
currentPage); ?kz+R'
int totalPage = getTotalPage(everyPage, ^p/Ob'!
!!nuAQ"E[
totalRecords); h<\_XJJ
boolean hasNextPage = hasNextPage(currentPage, H<G4O02i_
3TZ*RPmFRm
totalPage); kY&h~Q
boolean hasPrePage = hasPrePage(currentPage); k%op>
&
v^7LctcVm
returnnew Page(hasPrePage, hasNextPage, EK$Kee}~
everyPage, totalPage, vHE^"l5 v
currentPage, Mf#83<&K
UYtuED
beginIndex); aRJ>6Q}
} ?P7]u>H
xlR2|4|8
privatestaticint getEveryPage(int everyPage){ 35x 0T/8
return everyPage == 0 ? 10 : everyPage; hwDbs[:
} UP{j5gR:_
Y}D onF
privatestaticint getCurrentPage(int currentPage){ =0'q!}._!
return currentPage == 0 ? 1 : currentPage; ]k8/#@19
} irZFV
Wi}FY }f
privatestaticint getBeginIndex(int everyPage, int 9cv]y#
TV}}dw
currentPage){ h`}3h<
8
return(currentPage - 1) * everyPage; 5')8r';,
} 9ElCg"
uGl| pJ\y=
privatestaticint getTotalPage(int everyPage, int @E53JKYhY
P~FUS%39"o
totalRecords){ 1Fi86
int totalPage = 0; qJ_1*!!91
Sm2>'C
if(totalRecords % everyPage == 0) 8Z2.`(3c[
totalPage = totalRecords / everyPage; JkA|Qdj~Mr
else $Vv}XMxw
totalPage = totalRecords / everyPage + 1 ; p=QYc)3F
:b,^J&~/)1
return totalPage; N|2y"5
} Y3ZK%OyPR
J%]D%2vnk`
privatestaticboolean hasPrePage(int currentPage){ S|GWcSg
return currentPage == 1 ? false : true; '?yCq$&
} Ab1/.~^
FCc=e{
privatestaticboolean hasNextPage(int currentPage, e|r0zw S
ARfRsPxr
int totalPage){ k 2%S`/:
return currentPage == totalPage || totalPage == G 8Y+w
,A5) <}
0 ? false : true; <39!G7ny
} lKEa)KF[
Y#01o&f0n
k,Zm GllQ]
} bO/*2oau
,goBq3[%?
W:QwHZ2O
C+MSVc
XDD<oo
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。 wp.TfKxw
!1uzX
Kb
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 [[)_BmS5r
!
qJI'+_
做法如下: C6&( c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 YTU.$t;Ez
ER{3,0U
的信息,和一个结果集List: $'[q4 wo<
java代码: \`xkp[C
y02u?wJ
XvSIWs
/*Created on 2005-6-13*/ }+Vv0jX|V
package com.adt.bo; 8Vt4HD 08
qSO*$1i
import java.util.List; 5QWNZJ&}d
,dd WBwMK
import org.flyware.util.page.Page; Pcu|k/tk
lz~J"$b
/** s([Wn)I
* @author Joa <2P7utdZ
*/ )8{6+{5lu
publicclass Result { xNN@ 1P[*
P?3{z="LzJ
private Page page; ]i8c\UV \
wh~sZ
private List content; uf@U:V
27#8dV?
/** h#3m4<w(9
* The default constructor MPRO
!45Z
*/ 3^G96]E
public Result(){ mT_GrIl[
super(); CJqc\I~
} dA#{Cn;
F1A1@{8bN
/** `%E9xcD%
* The constructor using fields ~r`Wr`]_ z
* G+Dpma ]
* @param page X_70]^XL
* @param content mPmB6q%)]
*/ \].J-^=
public Result(Page page, List content){ WSI
Xj5R
this.page = page; (Imp
$
this.content = content; IM-`<~(I#
} =wA5P@
Rk<%r k
/** P&t;WPZ
* @return Returns the content. DcFCKji
*/ i@$-0%,
publicList getContent(){ *e<_; Kr?
return content; _F8T\f|
} LC'2q*:'
Gm&2R4 )EP
/** U4_"aT>My
* @return Returns the page. gGKKs&n7
*/ : z~!p~
public Page getPage(){ w6EI{
return page; 3%M.U)|+
} NdQ%:OKC
~Ob8i 1S>
/** :k1$g+(lP
* @param content Z! YpklZ?~
* The content to set. 4
10:%WGc
*/ ULvVD6RQ47
public void setContent(List content){ #O</\|aH)i
this.content = content; !s-/0ugZ
} w<d*#$[,*
&`PbO
/** j+1KNH
* @param page >}F? <JB
* The page to set. L<@&nx
*/ $'$>UFR
publicvoid setPage(Page page){ R|t;p!T
this.page = page; Bz]J=g7
} $GF&x>]]
} HIPL!ss]
kGD|c=K}
MYTS3(
`D)S-7BR
+(AwSh !
2. 编写业务逻辑接口,并实现它(UserManager, R ]=SWE}U
MhH);fn
UserManagerImpl) Z1]"[U[;
java代码: q)Je.6$#X
\UtS>4w\
l%bq2,-%
/*Created on 2005-7-15*/ fNEz
package com.adt.service; |E|T%i^}./
/'Bdq?!B&
import net.sf.hibernate.HibernateException; /\~W$.c
M,L@k
import org.flyware.util.page.Page; +UaO<L
dP3VJ3+
%
import com.adt.bo.Result; t~~r-V":
kGj]i@(PA4
/** o*)@oU
* @author Joa g*r/u;
*/ QX/]gX
publicinterface UserManager { 3YRBI|XO
;@'0T4Z&l
public Result listUser(Page page)throws P6E1^$e
/'NUZ9
HibernateException; sbjtL,
`]LODgk~
} feg`(R2
dp< auA
| /#'S&!U
2?H@$-x>
T Xl\hL\+
java代码: j@V$Mbv
\#_@qHAG
UNY@w=]<
/*Created on 2005-7-15*/ 1G_xP^H!
package com.adt.service.impl; a}GAB@YI
Vd[2u
import java.util.List; KPg[-d
\
>(zunL
import net.sf.hibernate.HibernateException; FP@A;/c
6DO0zNTY
import org.flyware.util.page.Page; }9FD/
import org.flyware.util.page.PageUtil; o5V`'[c
g`
kZT} h
import com.adt.bo.Result; gx#J%k,f
import com.adt.dao.UserDAO; :X|AW?*
import com.adt.exception.ObjectNotFoundException; AYYRxhv_,
import com.adt.service.UserManager; eAU"fu6d
ev*c4^z:s
/** g)nXo:)&