Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;W7 hc!
|Du,UY/
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 wVgi+P
?. zu2
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 bK3B3r#$
9t{|_G
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 0jR){G9+
T>#TDMU#Fm
。 Y 3o^Euou
+w "XNl
分页支持类: {]&R8?%
2Sge
java代码: pO"m~ mpA
1^aykrnQ>
;"1/#CY773
package com.javaeye.common.util; ^DBD63N"
L~*u4
import java.util.List; !xkj30O(G
'sj9[o@]
publicclass PaginationSupport { sf Dg/ a
3PsxOb+
publicfinalstaticint PAGESIZE = 30; R=`U 4Ml;
\).Nag +
privateint pageSize = PAGESIZE; za,6du6
fC_zX}3
privateList items; }%eDEM
}dy9IH
privateint totalCount; A?e,U,
"?$L'!bM@
privateint[] indexes = newint[0]; 6|QTS|!
P,(9cyS{
privateint startIndex = 0; ,#
]+HS^B
$zdd=.!KiK
public PaginationSupport(List items, int X*0k>j
4Mk8Cpz
totalCount){ Y|mW.
setPageSize(PAGESIZE); MzcB3pi
setTotalCount(totalCount); x'@W=P 7
setItems(items); g{e/X~
setStartIndex(0); 21U&Ww
} 5)w4)K-%
Zw+=ng.q?
public PaginationSupport(List items, int 8pqs?L@W
^D>fis
totalCount, int startIndex){ ]* 0(-@
setPageSize(PAGESIZE); '?5S"??
setTotalCount(totalCount); +6
ho)YL
setItems(items); 2zhn`m
setStartIndex(startIndex); \fTTkpM
} j(sLK
&
W;qP=DK2
public PaginationSupport(List items, int C?/r;
GSP?X$E
totalCount, int pageSize, int startIndex){ CA/ -Gb
setPageSize(pageSize); SgiDh dE
setTotalCount(totalCount); 2SYKe$e
setItems(items); Hj2<ZL
setStartIndex(startIndex); Hoj8okP
} vTdUuj3N
]
@ufV
publicList getItems(){ >
V8sm/M
return items; 0 <g{ V
} 4h;4!I|
n,CD
publicvoid setItems(List items){ DY8(g=TI|1
this.items = items; Yr=8!iR$
} GLCAiSMz[
sZKEUSFD #
publicint getPageSize(){ RB[/q:
return pageSize; _C20 +PMO
} ul$,q05nb
6(Vhtr2(*
publicvoid setPageSize(int pageSize){ J smB^
this.pageSize = pageSize; ~T%Ui#Gc
} e9 *lixh
E:)Cp
publicint getTotalCount(){ :5jexz."M
return totalCount; #BsW
} P].eAAXnP
}-74 f
publicvoid setTotalCount(int totalCount){ aZ6'|S;
if(totalCount > 0){ <6/= y1QC)
this.totalCount = totalCount; 0'`S,
int count = totalCount / Ps3~{zH`
.%IslLZ
pageSize; g8RPHjvZ
if(totalCount % pageSize > 0) eeW`JG-E
count++; Kk=LXmL2
indexes = newint[count]; J:AMnUOcDi
for(int i = 0; i < count; i++){ @MOCug4
indexes = pageSize * xz8G}Ku
FIS "Z(
i; {rDq_^
} JGis" e
}else{ f0DK>L
this.totalCount = 0; 0elxA8Z~e
} wx*1*KZ
} 6Hk="$6K
8eN7VT eb
publicint[] getIndexes(){ FAw1o
return indexes; <: :VCA %
} $Asr`Q1i
m'bi\1Q
publicvoid setIndexes(int[] indexes){ Wo!;K|~P
this.indexes = indexes; R&*@@F-dx
} {n&Uf{
dxCPV6 XI
publicint getStartIndex(){ 45<y{8
return startIndex;
DkdL#sV
} Ys3uPs
35_)3R)
publicvoid setStartIndex(int startIndex){ e>AXXUEf
if(totalCount <= 0) DZk1ZLz
this.startIndex = 0; f@d9Hqr+l;
elseif(startIndex >= totalCount) m(_9<bc>
this.startIndex = indexes Us=eq "eu
Vm,,uF
[indexes.length - 1]; I3(d<+M
elseif(startIndex < 0) "(f`U.
this.startIndex = 0;
oL-2qtv
else{ psUE!~9,
this.startIndex = indexes nZ
E )_
%j5ywr:
[startIndex / pageSize]; to>
} o2naVxetE
} C?o6(p"b
(` c
G
publicint getNextIndex(){ |##GIIv;i
int nextIndex = getStartIndex() + <cj{Qk
d:rGyA]
pageSize; U\vY/6;JI
if(nextIndex >= totalCount) 4TZ cc|B5
return getStartIndex(); J#
EP%
else :c=.D;,
return nextIndex; cbYK5fj"T
} (s&&>M]r_
?JXa~.dA
publicint getPreviousIndex(){ UQPU"F7.
int previousIndex = getStartIndex() - 5jZiJw(
E ]f)Os$
pageSize; D(\$i.,b2
if(previousIndex < 0) Bm /YgQi
return0; r,;\/^ u*
else ^B]@Lr E^
return previousIndex; ;dZMa]X0
} [Y/:@t"2y
+>tUz D
} Ll}yJ#3,
+}JM&bfK
,Eu?JH&}u
e|lD:_1i
抽象业务类 v~=\H
java代码: v("wKHWTI@
d5!!Ut
J^
G
/** Apfnx7Fv
* Created on 2005-7-12 ;Gd~YGW^#
*/ MbA\pG'T
package com.javaeye.common.business; 4 b,N8
2?DRLF]
import java.io.Serializable; {_>em*V b
import java.util.List; 5o0Ch
kbI/4IRW
import org.hibernate.Criteria; Ed-M7#wY
import org.hibernate.HibernateException; ,={t8lN
import org.hibernate.Session; {' 5qv@3
import org.hibernate.criterion.DetachedCriteria; m;,xmEp
import org.hibernate.criterion.Projections; 7wVH8^|
import ^4pto$#@O:
rx!=q8=0R
org.springframework.orm.hibernate3.HibernateCallback; n7! H:{L
import FHg0E++?
WNy3@+@GZ
org.springframework.orm.hibernate3.support.HibernateDaoS 46No%cSiG
A)NkT`<)
upport; 2`bdrRD0
(K<9hL+X
import com.javaeye.common.util.PaginationSupport; l"pN90B4
C+N k"l9
public abstract class AbstractManager extends Qa4MZj;$K
EgM*d)X
HibernateDaoSupport { JL^2l$up
]?LB?:6
privateboolean cacheQueries = false; zP) ~a
~
'Vxg}
privateString queryCacheRegion; C9~~O~7x
#Dy?GB08
publicvoid setCacheQueries(boolean X#p Wyo~
TqAPAHg
cacheQueries){ BmBz}:xMez
this.cacheQueries = cacheQueries;
%X1x4t]
} z`3( ,V
l67Jl"v
publicvoid setQueryCacheRegion(String diT=x52
q|(W-h+
queryCacheRegion){ (<c7<_-H
this.queryCacheRegion = =|U@
TzG]WsY_
queryCacheRegion; o
l ({AYB
} sen=0SB/
zI;0&
publicvoid save(finalObject entity){ WF2-$`x
getHibernateTemplate().save(entity); ~r*P]*51x
} dcfe_EuT
nsuX*C7
publicvoid persist(finalObject entity){ xge7r3i
getHibernateTemplate().save(entity); #JW+~FU`
} 9pSUIl9|j
3iX?~
publicvoid update(finalObject entity){ |U'I/A
getHibernateTemplate().update(entity); svhI3"r
} kxB.,'
q_fam,9
publicvoid delete(finalObject entity){ iCQ>@P]nE
getHibernateTemplate().delete(entity); 5Fw - d
} CNrIIsJ
[]pN$]+c
publicObject load(finalClass entity, Yl^mAS[w&
Z;DCI-Wg
finalSerializable id){ dJk9@u
return getHibernateTemplate().load 4=<*Vd`p
i@P}{
(entity, id); jLVl4h&
} S?0$? w?
oF&l-DHp
publicObject get(finalClass entity, }"s;\?a
#ToK$8
finalSerializable id){ lS5ny
return getHibernateTemplate().get b^CNVdo'
L"(4R^]
(entity, id); H`QQG!
} D-p.kA3MJ
}
p:%[
publicList findAll(finalClass entity){ 6"
B%)0
return getHibernateTemplate().find("from 5<YzalNf
V9%aBkf8w
" + entity.getName()); \IM4Z|NN"
} GZ #aj|
['qnn|
publicList findByNamedQuery(finalString :$r ^_
L"+$Wc[|
namedQuery){ 2f:^S/.A
return getHibernateTemplate evuZY X@
$)~
().findByNamedQuery(namedQuery); ef"?|sn
} I/J7rkf
sy5 Fn~\R
publicList findByNamedQuery(finalString query, bZwnaM4"F
~l E _L1-c
finalObject parameter){ z? ]G3$i(
return getHibernateTemplate -0uV z)
2@j";+
().findByNamedQuery(query, parameter); #s5N[uK^m
} rRFAD{5)
oYM3Rgxf9Q
publicList findByNamedQuery(finalString query, hVpCB,
va)%et0!
finalObject[] parameters){ n~IVNB*
return getHibernateTemplate L V{Q,DrP
>]D4Q<TY
().findByNamedQuery(query, parameters); @* ust>7
} UK[v6".^h
J5M+FwZq
publicList find(finalString query){ [1G^/K"
return getHibernateTemplate().find >!6JKL~=
gXFWxT8S
(query); cI0 ]}S
} vb{i
r#i?j}F}
publicList find(finalString query, finalObject :;]Oc
P\2M[Gu(Q
parameter){ Rd*[%)
return getHibernateTemplate().find oA-:zz>wL
~p1EF;4 #
(query, parameter); X@2-*so<
} J;Rv ~<7
S::=85[>z
public PaginationSupport findPageByCriteria \E1U@6a
32)tJ|m
(final DetachedCriteria detachedCriteria){ QCOo
return findPageByCriteria .^(/n9|o-
+C]&2zc.
(detachedCriteria, PaginationSupport.PAGESIZE, 0); j{++6<tr
} 256LH Y|6
y2L#:[8
public PaginationSupport findPageByCriteria }ut]\]b
F"+o@9]
(final DetachedCriteria detachedCriteria, finalint m` AK~O2
D=f7NVc >Q
startIndex){ {}~: &.D
return findPageByCriteria YvL?j
/7c~nBU
(detachedCriteria, PaginationSupport.PAGESIZE, $rB3m~c|
)eeN1G`rDE
startIndex); ]jMKC8uz
} tl yJmdl
T.e.{yO
public PaginationSupport findPageByCriteria [IZM.r`Z
x[_=#8~.1x
(final DetachedCriteria detachedCriteria, finalint 8,T4lb<<
v5}X+'
pageSize, h!@,8y[B
finalint startIndex){ zt24qTKL
return(PaginationSupport) >pyj]y^3
Njc%_&r
getHibernateTemplate().execute(new HibernateCallback(){ dhPKHrS
publicObject doInHibernate XUMX*
w&h2y4
(Session session)throws HibernateException { ed 59B)?l
Criteria criteria = Q[n\R@
Rg&-0b
detachedCriteria.getExecutableCriteria(session); 'fV%Z
int totalCount = Pz_Oe,{.I
}CL"S_>1
((Integer) criteria.setProjection(Projections.rowCount <~U4*
W[bmzvJ_X
()).uniqueResult()).intValue(); K]oM8H1
criteria.setProjection ^y.nDs%ZT7
C2U~=q>>
(null); rt-\g1x
List items = &$FvWFRh#
nv0@xnbz
criteria.setFirstResult(startIndex).setMaxResults #EO1`9f48x
e9pOisZ;8
(pageSize).list(); G`h+l<
PaginationSupport ps = 'vV$]/wBF
jF ^5}5U
new PaginationSupport(items, totalCount, pageSize, }alj[)
<~emx'F|
startIndex); }3 m0AQ;K
return ps; I`RBj `IF
} vE, 37
}, true); \kIMDg3}
} GV|9H]_,I
shC;hR&;
public List findAllByCriteria(final :t$aN|>y
ihe(F7\U
DetachedCriteria detachedCriteria){ 8kL4~(hY
return(List) getHibernateTemplate R,2=&+ e
%y[1H5)3<
().execute(new HibernateCallback(){ O>y'Nqz
publicObject doInHibernate 7Ey#u4Q
j`*N,*ha
(Session session)throws HibernateException { 8ovM\9qT
Criteria criteria = XE3aXK'R
{QaNAR=)
detachedCriteria.getExecutableCriteria(session); 'm=*u
SJK
return criteria.list(); 8OhDjWVJ
} 7k%T<;V
}, true); 5ABhj* 7
} [dX`K`k
z2c5m
public int getCountByCriteria(final M(q'%XL^
e&q?}Ho
DetachedCriteria detachedCriteria){ l]!9$
Integer count = (Integer) '(+<UpG_Q}
Tpp &
getHibernateTemplate().execute(new HibernateCallback(){ ?^#lWx q
publicObject doInHibernate /?-7Fg+,
6R UrF
(Session session)throws HibernateException { 34|a\b}
Criteria criteria = Gi6T["
Xk mQBV"
detachedCriteria.getExecutableCriteria(session); H jNxqaljt
return Btt]R
Yd
cK&{
criteria.setProjection(Projections.rowCount er.L7
a l9.}
()).uniqueResult(); \(UKdv
} {U!St@
}, true); Z{NC9
return count.intValue(); VObrlOkp
} XEM'}+d
} S]3Ev#>
`\|ssC8u
ov#7hxe
qk(P>q8[
g+8hp@a
nxm$}!Df
用户在web层构造查询条件detachedCriteria,和可选的 ,.IEDF<&
(WlIwKP
startIndex,调用业务bean的相应findByCriteria方法,返回一个 .S\&L-{
xFv;1Q
PaginationSupport的实例ps。 JOnyrks
4JIYbb-a'
ps.getItems()得到已分页好的结果集 th5g\h%j*
ps.getIndexes()得到分页索引的数组 ^t"iX9
ps.getTotalCount()得到总结果数 ra '
ps.getStartIndex()当前分页索引 %i0?UpA
ps.getNextIndex()下一页索引 ;(6g\'m
ps.getPreviousIndex()上一页索引 Rs& @4_D
xgsjm))
^D67y%
BfTcI)
/nx'Z0&+X
:7N3N
L *[K>iW
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 wRNroQ
=dP{ Gh
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 c>bq%}
2LY=DL7
一下代码重构了。 !{^\1QK
O OFVnu
我把原本我的做法也提供出来供大家讨论吧: 9X<OJT;3J
xom<P+M!|
首先,为了实现分页查询,我封装了一个Page类: {1J&xoV"
java代码: a)-FGP^
bucR">_p
7Ob*Yv=[
/*Created on 2005-4-14*/ u8zbYd3
package org.flyware.util.page; \6|/RFT
,FQdtNMap
/** 0IM8
* @author Joa "R
#k~R
* woH)0v
*/ w[Gh+L30=5
publicclass Page { 72oWhX=M%
s0UFym8
/** imply if the page has previous page */ qd@&59zSh
privateboolean hasPrePage; )4Q?aMm
|w}w.%
/** imply if the page has next page */ 6`01EIk
privateboolean hasNextPage; hm$X]H`uMX
^{@!['
/** the number of every page */ U$&hZ_A
privateint everyPage; iGXI6`F"
`xS{0P{uj
/** the total page number */ t-%Q`V=[
privateint totalPage; $9
p!Y}
&(rWw Oo6
/** the number of current page */ ri~<~oB2:
privateint currentPage; 1r[@(c0
)QKf7 [:
/** the begin index of the records by the current {C*\O)Gep
-#`c5y}P
query */ "7%:sty
privateint beginIndex; omZO+=8Q
-PB[-CX
[^H"FA[
/** The default constructor */ v"u^M-_
public Page(){ ][PzgzG
~o3Hdd_#}N
} C}g9'jY
XdgUqQb}
/** construct the page by everyPage Hq &"+1F
* @param everyPage D6D1S/:ij'
* */ Z~G my7h(
public Page(int everyPage){ PnT)LqEF
this.everyPage = everyPage; 6Q|k7*,B
} $*[{J+t_
dBCbL.!
/** The whole constructor */ |BMV.Zi
public Page(boolean hasPrePage, boolean hasNextPage, Rxpn~QQ
K2_Qu't0$
mumXUX
int everyPage, int totalPage, ]pA(K?Lbg
int currentPage, int beginIndex){ \79X{mcd
this.hasPrePage = hasPrePage; *2"6fX[
this.hasNextPage = hasNextPage; rk2xKm^w
this.everyPage = everyPage; }|)R
this.totalPage = totalPage; 2 mjV~
this.currentPage = currentPage; lB8il2&
this.beginIndex = beginIndex; 5,"l0nrk
} wVs.Vcwr
>r5P3G1
/** `\>.h
* @return +y+"Fyl
* Returns the beginIndex. xk~IN%\
*/ z1OFcqm
publicint getBeginIndex(){ EfLO5$?rm
return beginIndex; td2/9|Q
} w-B^
[<
R
/** u?ek|%Ok
* @param beginIndex I&c ~8Dw
* The beginIndex to set. )-rW&"{U
*/ H14Ic.&
publicvoid setBeginIndex(int beginIndex){ U09.Y
this.beginIndex = beginIndex; ;|%dY{L-
} gB,G.QM*6
S&nxok`e^
/** ewNz%_2
* @return :!&;p
* Returns the currentPage. qMBR *f
*/ l|`9:H
publicint getCurrentPage(){ zZ-wG
return currentPage; -a Gcf]6
} f},oj4P\
^he=)rBb?
/** Yx'res4e
* @param currentPage ?C0l~:j7D
* The currentPage to set. dGfVZDsr]
*/ gxPx&Z6jF
publicvoid setCurrentPage(int currentPage){ O^>jdl!TZ
this.currentPage = currentPage; UCrh/b Tm
} 3CjL\pIC
FUK3)lT
/** WnFG{S{s
* @return !33#. @[
* Returns the everyPage. gCd`pi
8
*/ `[#x_<\t
publicint getEveryPage(){ :m=m}3/:
return everyPage; OIHz I2{
} u]^N&2UW
[mxTa\
/** /76 1o\Q
* @param everyPage Rr(* aC2P
* The everyPage to set. +!-~yf#RE
*/ h~U02"$
publicvoid setEveryPage(int everyPage){ ylf[/='0K
this.everyPage = everyPage; Sgb*tE)T
} U7mozHS,:9
PHg48Y"Nd
/** et,GrL)l
* @return jg
2qGC
* Returns the hasNextPage. ^ OJyN,A
*/ t-u|U(n
publicboolean getHasNextPage(){ =bh*[,-
return hasNextPage; NY$uq+Z>
} "i.r@<)S
nm$Dd~mxW1
/** d&cU*
* @param hasNextPage SQsSa1
* The hasNextPage to set. %,@vWmn
*/ x)rlyjFM
publicvoid setHasNextPage(boolean hasNextPage){ ? Q@kg
this.hasNextPage = hasNextPage; ~cAZB9Fa
} ub0zJTFJ#
k@>\LR/v
/** ){s*n=KIO
* @return vqslirC
* Returns the hasPrePage. <O?y-$~
*/ ;cQW sTfT
publicboolean getHasPrePage(){ _,Fny_u=;
return hasPrePage; _fFU#k:MU
} 1PaUI#X"2F
A\rt6/
/** <HWS:'1
* @param hasPrePage @4~=CV%j
* The hasPrePage to set. Dq\ Jz~
*/ J`M&{UP
publicvoid setHasPrePage(boolean hasPrePage){ |XYEn7^r
this.hasPrePage = hasPrePage; eC
DIwB28
} 8GPIZh'0h
\2[<XG(^
/** zHWSE7!
* @return Returns the totalPage. ?B@;QjhjiJ
* mN`YuR~
*/ P47V:E%
publicint getTotalPage(){ 'PZ|:9FX!
return totalPage; 9DQ)cy
} TjWE_Bq]g
2 gq$C"
/** GJi~y
* @param totalPage 05Fz@31~
* The totalPage to set. 148V2H)
*/ ?[TfpAtQ`
publicvoid setTotalPage(int totalPage){ dCYCHHHF
this.totalPage = totalPage; 9 A,Z|q/z5
} dBsX*}C
h[KvhbD3
} uy _wp^
cxeghy:;U
3:/'t{ ^B
xVB;s.'!
{3a&1'a0g
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 ,y`CRlr:
h<<>3 A
个PageUtil,负责对Page对象进行构造: @K223?c8l
java代码: %A1@&xrbl
R;whW:Tx
))D:8l@
/*Created on 2005-4-14*/ .D,p@4
package org.flyware.util.page; g]@(E
z2gk[zY&
import org.apache.commons.logging.Log; Zv]x'3J#Y
import org.apache.commons.logging.LogFactory; <>xJn{f0c
-Lu)'+
/** %m,6}yt
* @author Joa Kr'f- {
* c'6g*%2k
*/ 'XQ`g CF=
publicclass PageUtil { <oKGD50#
l}^3fQXI
privatestaticfinal Log logger = LogFactory.getLog DDT_kK;
xp'_%n~K@
(PageUtil.class); }UJv[
UEs7''6RM
/** %t=kdc0=_
* Use the origin page to create a new page +i ?S
* @param page +=Jir1SLV
* @param totalRecords >%p{38
* @return !1T\cS#1%
*/ MfO:m[s
publicstatic Page createPage(Page page, int 7`vEe'qz
CQ7{1,?2
totalRecords){ G2 ]H6G$M
return createPage(page.getEveryPage(), !J1rRPV
_cTh#t ^
page.getCurrentPage(), totalRecords); 'oNO-)p\#!
} DBLk!~IF
*,C(\!b
!?
/** 7 J^rv9i4
* the basic page utils not including exception mvW%
w&$d* E
handler rt3qdk5U
* @param everyPage #
?1Sm/5k`
* @param currentPage [P zv4+
* @param totalRecords }<@j'Ok}.
* @return page 2n><RZ/9
*/ =@Dwlze
publicstatic Page createPage(int everyPage, int I4;A8I
3K&4i'}V
currentPage, int totalRecords){ 84HUBud76Y
everyPage = getEveryPage(everyPage); 0`.^MC?
currentPage = getCurrentPage(currentPage); ^m#-9- `
int beginIndex = getBeginIndex(everyPage, R_]{2~J+
iUMY!eqp
currentPage); g
6]epp[8
int totalPage = getTotalPage(everyPage, eAUcv`[#p
/-zXM;h
totalRecords); hc
(e$##
boolean hasNextPage = hasNextPage(currentPage, nMDxH$O
rWys'uc
totalPage); &uP~rEJl+
boolean hasPrePage = hasPrePage(currentPage); o)6p A^+
U~{du;\
returnnew Page(hasPrePage, hasNextPage, nKR{ug>I)
everyPage, totalPage, ?oZR.D|SZ
currentPage, qbrp P(.
WPZ?*Sx
beginIndex); (npj_s!.C)
} 5tJ,7Y'
*vgl*k?)
privatestaticint getEveryPage(int everyPage){ R(.}C)q3
return everyPage == 0 ? 10 : everyPage; +[\eFj|=
} ,h|q i[7
f~E*Zz`;
privatestaticint getCurrentPage(int currentPage){ Vc^HVyAx@n
return currentPage == 0 ? 1 : currentPage; $VAx:Y|
} jR=s#Xz
>56>*BHD
privatestaticint getBeginIndex(int everyPage, int x@mL $
&aM7T_h8
currentPage){ GdB.4s^
return(currentPage - 1) * everyPage; _'4A|-9
} NmK8<9`u
01!s"wjf
privatestaticint getTotalPage(int everyPage, int V)Z70J<'
d]9U^iy
totalRecords){ Bwr3jV?S
int totalPage = 0; Z\[N!Zt|
C]^H&
if(totalRecords % everyPage == 0) Li*eGlId
totalPage = totalRecords / everyPage; bo.(zAz
else HM>lg`S
totalPage = totalRecords / everyPage + 1 ; u66XN^
'=][J_
return totalPage; j4=(H:c~E
} yH][(o=2
AM=z`0so
privatestaticboolean hasPrePage(int currentPage){ kq\)MQ"/X
return currentPage == 1 ? false : true; .CP&bJP%
} zMIT}$L
Zmbfq8K
privatestaticboolean hasNextPage(int currentPage, dr4Z5mw"E
I ZQHu h
int totalPage){ l
& Dxg
return currentPage == totalPage || totalPage == t|t#vcB
6c0>gUQx-
0 ? false : true; /0\
mx4u
} G0E121`h
#plY\0E@
~>9_(L
} q2HYiH^L
4k./(f2+
&.TTJsKG h
U%0Ty|$Y
gGfoO[B
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。 8Sz})UZ
Spt?>sm
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 s3Cc;#
JTi!Xu5Jq
做法如下: 5zON}"EC
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 8p[)MiC5W^
r1RG TEkD
的信息,和一个结果集List: 1CLL%\V
java代码: 5nbEf9&
)O:0]=#))
26CS6(sn
/*Created on 2005-6-13*/ 6(PM'@i
package com.adt.bo; 0'nikLaKy
E7-@&=]v
import java.util.List;
Ov<NsNX]
OR[{PU=X
import org.flyware.util.page.Page; !!Z?[rj
z3?o|A }/W
/** @k&qb!Qah
* @author Joa GfC5z n>
*/ 6'xsG?{JY
publicclass Result { j65<8svl
I%urz!CNE*
private Page page; U*.0XNKp{
}-~l!
private List content; J90v!p-
YJ$1N!rG
/** m,fAeln
* The default constructor $.]l!cmi%Q
*/ 6;b~Ht
public Result(){ +^;JS3p@\
super(); ,@5I:X!rR
} \TU3rk&X
I}R0q
/** J4Dry<
* The constructor using fields Y3Q9=u*5
* R:B^
* @param page qe5feky
* @param content J=/5}u_gw
*/ *2jK#9"MP
public Result(Page page, List content){ r&FDEBh
this.page = page; Yw0[[N<SW
this.content = content; Ewg:HX7<(
} R##~*>#
mc4i@<_?
/** ;J7F J3n
* @return Returns the content. o=`C<}
*/ jlxpt)0i
publicList getContent(){ 2#k5+?-c61
return content; AlJ} >u
} *?MGMhE
fDLG>rXPT
/** =FD;~
* @return Returns the page. Ha)ANAD
*/ :,)lm.}]t
public Page getPage(){ <F04GO\
return page; "jw<V,,
} T1H"\+
J`2"KzR0w"
/** )m. 4i =X
* @param content 7B?c{
* The content to set. u(G*\<z-
*/ V*~Zs'L'E
public void setContent(List content){ =JmT:enV
this.content = content; f7}*X|_Y
} Dl}$pN
O+ICol
/** cv`~y'?D
* @param page c%qv9
* The page to set. C`q@X(_
*/ ,cqF3
publicvoid setPage(Page page){ Q$fmD
this.page = page; A@Dw<.&_I
} sq'Pyz[[
} YID4w7|
VH:]@x//{
Od|$Y+@6
#^]n0!
mml
z&h
2. 编写业务逻辑接口,并实现它(UserManager, P67o{EdK
5scEc,JCi
UserManagerImpl) AoyX\iqQ
java代码: M>/Zbnq
aCL!]4K84$
jq!tT%o*B
/*Created on 2005-7-15*/ 4
uQT5
package com.adt.service; K^R,Iu/M
@$z<i `4
import net.sf.hibernate.HibernateException; e>AE8T
{`w;39$+
import org.flyware.util.page.Page; R=KQ
vI@%Fg+D
import com.adt.bo.Result; wiBVuj#
Ot`VR&}
/** qcT'nZ:
* @author Joa ,#8e_3Z$
*/ n..g~$k
publicinterface UserManager { ^urDoB:
Q1z;/A$Al
public Result listUser(Page page)throws C$5[X7'
%!1Q P[}K
HibernateException; _l1NKk
`ta7Gc/:UY
} *Aa?yg:=
fYW6b[lI
%D[0nt|X
5>TK^1
:
l\n@cQR
java代码: kTvd+TP4
9 '2_
t N2Md}@e
/*Created on 2005-7-15*/ !e?.6% %
package com.adt.service.impl; R,Vd.-5M
c?@T1h4
import java.util.List; p*P)KP
&/Q0
import net.sf.hibernate.HibernateException; _H/8_[xk
?)#5X_V-q
import org.flyware.util.page.Page; "V}[':fen
import org.flyware.util.page.PageUtil; >&U,co$>
H8On<C=
import com.adt.bo.Result; Z@$8I{}G
import com.adt.dao.UserDAO; l(#)WWr+
import com.adt.exception.ObjectNotFoundException; `F>O; >i''
import com.adt.service.UserManager; fX|Y;S-@+
>_LDMs[-p
/** T'b_W,m~,u
* @author Joa =*LS%WI
*/ %x}
O1yV
publicclass UserManagerImpl implements UserManager { $O5UyKI
)<Hd T
private UserDAO userDAO; s
S7c!
vZBc!AW
/** [r[=W!
* @param userDAO The userDAO to set. -bU oCF0
*/ 9*(aUz9j
publicvoid setUserDAO(UserDAO userDAO){ |*0<M(YXN
this.userDAO = userDAO; xagBORg+Bd
} Dmu/RD5X:
*~x/=.}
/* (non-Javadoc) 0/oyf]HR
* @see com.adt.service.UserManager#listUser Ny%(VI5:
c=`wg$2:5
(org.flyware.util.page.Page)
l
c '=mA
*/ @Rw!'T
public Result listUser(Page page)throws v@d
:EA\)@^$R
HibernateException, ObjectNotFoundException { TU
1I} ,
int totalRecords = userDAO.getUserCount(); lgtC |kM=
if(totalRecords == 0) ~((w?Yy"v
throw new ObjectNotFoundException J":,Vd!*-
=%BZ9,l
("userNotExist"); \R;`zuv
page = PageUtil.createPage(page, totalRecords); qhz]Wm P
List users = userDAO.getUserByPage(page); (#E.`e1#6
returnnew Result(page, users); ok4@N @
} RSfzRnhmr
^!by3Elqqk
} {7/0< NG
+@/"%9w
|UxG $M(
`WH"%V:"Q
.8G@%p{,
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,5*eX
ksN+?E4w
询,接下来编写UserDAO的代码: }I2@%tt?
3. UserDAO 和 UserDAOImpl: WpRc)g:
java代码: PuZf/um
6<ZkJ:=
o$Z6zm xO
/*Created on 2005-7-15*/ b^$|Nz;
package com.adt.dao; Os1>kwC
n0e1k.A
import java.util.List; ]h5Yg/sms
YS%h^>I^
import org.flyware.util.page.Page; GJqJlgHe
\0f{S40
import net.sf.hibernate.HibernateException; W0]gLw9*
5qP:/*+
/** qDfd. gL
* @author Joa %GS(:]{n
*/ #: [<iSk
publicinterface UserDAO extends BaseDAO { Ch3jxgQY
9
o&`5
publicList getUserByName(String name)throws rq/I` :
fL=~NC"
HibernateException; -B$2\ZE
jyZWVL:_
publicint getUserCount()throws HibernateException; eXf22;Lz
b8LLr;oQw
publicList getUserByPage(Page page)throws y`XU~B)J1
wLOB}ZMT
HibernateException; :HwA 5Z#
[+DW >Et
} <U\B!fO'
gY8>6'~mS
@("a.;1#o
p$3sME$L
_ "VkGG
java代码: SF<c0bR9
%Va!\#
`.Qi?* ^
/*Created on 2005-7-15*/ &?yZv{
package com.adt.dao.impl; VQS~\:1
I\$X/t +dH
import java.util.List; cbT7CG
Tap.5jHL
import org.flyware.util.page.Page; #a8B/-
VN\W]jT
import net.sf.hibernate.HibernateException; (j3xAA
import net.sf.hibernate.Query; YS *9t
Q{
-3=#u_
import com.adt.dao.UserDAO; !74S
W|g4z7Pb
/** 7M<'/s
* @author Joa bKN@j'M
*/ <yH4HY
public class UserDAOImpl extends BaseDAOHibernateImpl J.xPv)1'
*=I}Qh(1
implements UserDAO { #/<&*Pu5t
U5.LDv;
/* (non-Javadoc) <y NM%P<Oy
* @see com.adt.dao.UserDAO#getUserByName V13N}]
70Wgg ty
(java.lang.String) ?1K#dC52#
*/ vbC\?\_
publicList getUserByName(String name)throws #nPQ!NB/
K#=*9S
HibernateException { EH!
q=&d
String querySentence = "FROM user in class < F.hZGss7
a+Kj1ix
com.adt.po.User WHERE user.name=:name"; N%*5 T[.
Query query = getSession().createQuery j+uLV{~g6
P<a)25be/
(querySentence); 9E"vN
query.setParameter("name", name); O%5
r[
return query.list(); &N\jG373
} qfMo7e@6*
E4~<V=2l
/* (non-Javadoc) l^pA2yh|
* @see com.adt.dao.UserDAO#getUserCount() li}1S
*/ h1B16)
publicint getUserCount()throws HibernateException { `</ff+Q6
int count = 0; <#u=[_H
String querySentence = "SELECT count(*) FROM 9vGu0Um
to DG7XN}
user in class com.adt.po.User"; zU
gE~
Query query = getSession().createQuery |n,<1QY
iA' lon
(querySentence); 8L:ji,"
count = ((Integer)query.iterate().next -v]Sr33L
6'!4jh
()).intValue(); V`XNDNJ:
return count; {^7Hgg
} 5BlR1*
?7.7`1m!v
/* (non-Javadoc) eQp4|rf
* @see com.adt.dao.UserDAO#getUserByPage KmA;HiH%J
$+Z)
(org.flyware.util.page.Page) 0c<.iM
*/ d\R,Q
publicList getUserByPage(Page page)throws .ZVUd84B
\%f q
HibernateException { ~&7MkkftM
String querySentence = "FROM user in class 06c>$1-?
OHb[qX\
com.adt.po.User"; +RYls|f
Query query = getSession().createQuery '":lB]hS
g" .are'7
(querySentence); o4K ~
query.setFirstResult(page.getBeginIndex()) ]<cK";
.setMaxResults(page.getEveryPage()); w1OI4C)~
return query.list(); O$&mFL[`
} ,}ECF>
&3J_^210
} uao0_swW5
7 /VK##z
b`~p.c%(
w&o&jAb-M
7!EBH(,z
至此,一个完整的分页程序完成。前台的只需要调用 ~M7y*'oY
=F]FP5V
userManager.listUser(page)即可得到一个Page对象和结果集对象 +wN^c#~7
;>?rP88t
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}JrE,|
*KV0%)}sbL
webwork,甚至可以直接在配置文件中指定。 #xQr<p$L6
iS
WU'K
下面给出一个webwork调用示例: R3;Tk^5A
java代码: b\$}>O
Rv$[)`&T
&U5{Hm9Ynr
/*Created on 2005-6-17*/ _m
gHJ 0v'
package com.adt.action.user; %.^_Ps0
!'&n-Q
import java.util.List; WaVtfg$!
|
r&k48@
import org.apache.commons.logging.Log; T`\x,`
^
import org.apache.commons.logging.LogFactory; t>urc
import org.flyware.util.page.Page; :U3kW8;UMP
qln3 k`
import com.adt.bo.Result; |"/8XA
import com.adt.service.UserService; %_RQx2
import com.opensymphony.xwork.Action; D#il*
C)@y5. G;
/** a!<8\vzg
* @author Joa si`A:14R
*/ 52 fA/sx
publicclass ListUser implementsAction{ ES.fOdx
ZniB]k1
privatestaticfinal Log logger = LogFactory.getLog
-QM:
q
JORGj0v
(ListUser.class); aB{vFTD5
)z73-M V"
private UserService userService; j53*E
)d
h_:C+)13`x
private Page page; vq^f}id
5_I->-<
privateList users; ;#xmQi'`
4'`{H@]tb
/* \N!AXD
* (non-Javadoc) '=nQ$/!q
* % NA9{<I
* @see com.opensymphony.xwork.Action#execute() fPn>v)lN{
*/ #sPHdz'3M
publicString execute()throwsException{ 9`I _Et
Result result = userService.listUser(page); KxYwJ
page = result.getPage(); w+#C-&z
users = result.getContent(); a(kg/s
return SUCCESS; @SJL\{_
} tiB_a}5IB
)}D'<^=#T
/** _aFl_\3>
* @return Returns the page. rz wF~-m +
*/ Oiz ,w7LRh
public Page getPage(){ hxVKV?Fl
return page; s%C)t6`9
} B_nVP
Hv
sob
/** DnCP
aM4%
* @return Returns the users. 8+a4>8[M
*/ s \;" X
publicList getUsers(){ E^ P,*s
return users; q|o}+Vr
} DoJ\ q+
J&[@}$N
/** HJXT9;w
* @param page !UG
7Uer
* The page to set. 4
N H
*/ A+SE91m
publicvoid setPage(Page page){
ZHU5SXu
this.page = page; [ oL.+
} h U`wVy
*)ardZV${
/** R< ,`[* Z
* @param users Pz>s6 [ob
* The users to set. @&%'4j&+
*/ 2z6yn?'&L
publicvoid setUsers(List users){ <3xyjX'NE
this.users = users; x_|UPF
} 4}_j`d/8|
uw[<5
/** P3cR l']
* @param userService _LMM,!f
* The userService to set. LR.Hh
*/ TH; R
publicvoid setUserService(UserService userService){ & -{DfNK c
this.userService = userService; ]h>_\9qO
} L\)ZC
} ud xZ0
?nofUD.
?WF/|/
LJk@Vy <?
S4^vpY
DeN
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, mL{B!Q
#w,Dwy
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 7ePqmB<.
0vEoGgY0*:
么只需要: vy0X_DPCr
java代码: p<TpK )
?]Pmxp
H}
CN#+U,NZV
<?xml version="1.0"?> lsNrAA%m
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork {;N,t]>8M
]l1\? I
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;i
Fz?d3;
!lf|7
1.0.dtd"> fBRo_CU8!
yRSTk2N@
<xwork> biSz?DJ>
D2](da:]8)
<package name="user" extends="webwork- N}pw74=1
g#F?!i-[F
interceptors"> 2"Ecd
p[hZ@f(z
<!-- The default interceptor stack name b%<9Sn
&