Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9|`@czw
SMFW]I2T/
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &1{k^>oz
l1[IXw?
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 ("6W.i>
Y<+4>Eh
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 yd~fC:_ ]
t;]egk
。 bM-Rj1#Lo
:I('xVNPz
分页支持类: 12a #]E
(`u!/
java代码: B`aAvD`7
}}_uN-m
*PEuaRDN
package com.javaeye.common.util; o0L#39`'g
A] 9JbNV
import java.util.List; :c t+.#
j1<1D@UO
publicclass PaginationSupport { {p
0'Lc<3n
B>ZPn6?y
publicfinalstaticint PAGESIZE = 30; A&F4;>dms
q@9i3*q;
privateint pageSize = PAGESIZE; mmL~`i/
;Y^RF?un
privateList items; 81cmG`G7
p'qH [<s
privateint totalCount; xW =$j|
@45 H8|:k
privateint[] indexes = newint[0]; BT3O_X`u
^mpB\D)q
privateint startIndex = 0; CE,Om^
oDUMoX%4s
public PaginationSupport(List items, int \T9UbkR
\<B6>
totalCount){ WZ&@
J B
setPageSize(PAGESIZE); L@r.R_*H?s
setTotalCount(totalCount); sV[Z|$&Z
setItems(items); Xb*_LZAU
setStartIndex(0); h\d($Ki
} M[u3]dN
4d
G-
public PaginationSupport(List items, int =bWq 3aP)P
_KVB~loT
totalCount, int startIndex){ !^fR8Tp9
setPageSize(PAGESIZE); 3gy;$}Lq T
setTotalCount(totalCount); N RSse"
setItems(items); \STvBI?
setStartIndex(startIndex); Qu FCc1Q
} X.l"f'`l
~q(C j"7
public PaginationSupport(List items, int xm5FQ) T
0t?<6-3`/
totalCount, int pageSize, int startIndex){ ~#_$?_/(
setPageSize(pageSize); lMez!qx,=
setTotalCount(totalCount); N>%KV8>{L
setItems(items); T1HiHvJ
setStartIndex(startIndex); Xl6ZV,1=n7
} 0DIM]PS
IQ=|Kj9h
publicList getItems(){ ,7jiHF
return items; *.%)rm
} /%9p9$kFot
P=[x!}.I
publicvoid setItems(List items){ ;n{j,HB
this.items = items; <S@mQJS!y
} -!G#")<
S aet";pf`
publicint getPageSize(){ D.R|HqZ
return pageSize; 1vK(^u[
} lkWeQ)V
gc7:Rb^E5t
publicvoid setPageSize(int pageSize){ Rn(F#tI
this.pageSize = pageSize;
"rDzrz
} W#7-%oT
=tRe3o0(
publicint getTotalCount(){ -sH.yAvC6
return totalCount; k,iV$,[TF
} Ox*T:5
-_*XhD
publicvoid setTotalCount(int totalCount){ B
m@oB2x)
if(totalCount > 0){ TgE.=` "7
this.totalCount = totalCount; f9XO9N,hE:
int count = totalCount / :G=1$gb
b;`#Sea
pageSize; VE"0VB.
if(totalCount % pageSize > 0) &R FM
d=
count++; oy2dA
indexes = newint[count]; $4*E\G8
for(int i = 0; i < count; i++){ C+]q
indexes = pageSize * x*"pDI0k)
OjlB0
i; K^&
]xFW
} .'{6u;8
}else{ ID).*@(I"
this.totalCount = 0; _KhEwd
} +JAfHQm-
} VBsFT2XiL
iLd"tn'
publicint[] getIndexes(){ f+aS2k(e>
return indexes; QRZTT qG
} 9Glfi@.
Ysc|kxLb
publicvoid setIndexes(int[] indexes){ VDu
.L8
this.indexes = indexes; aU]O$Pg{
} Z=Y_;dS9
\%?8jQ'tX
publicint getStartIndex(){ t"bPKFRy9E
return startIndex; lp0T\
%
} ]7R&m)16
nK%/tdq
publicvoid setStartIndex(int startIndex){ I%Po/+|+
if(totalCount <= 0) b}?@syy8
this.startIndex = 0; Gp3nR<+
elseif(startIndex >= totalCount) `ToRkk&&>{
this.startIndex = indexes k1Mxsd
Gg pQ]rw
[indexes.length - 1]; #b"5L2D`y'
elseif(startIndex < 0) qqt.nrQ^
this.startIndex = 0; 0jJ28.kOp
else{ zTBi{KrZ
this.startIndex = indexes wI]R+.
k E#_Pc
[startIndex / pageSize]; L[D/#0qp
} ;$tv8%_L[
} q~'
K9
Jyz$&jqyr'
publicint getNextIndex(){ EBDC '^
int nextIndex = getStartIndex() + 5IE+M
uM#U!
pageSize; J,0WQQnb
if(nextIndex >= totalCount) q%kj[ZOY$]
return getStartIndex(); 7MuK/q.
else o|^?IQ7bpf
return nextIndex; 3VRZM@i
}
Eagmafu
B-ri}PA
publicint getPreviousIndex(){
G_, t\
int previousIndex = getStartIndex() - E_![`9i
Va/@#=,q]
pageSize; K,C$J
I
if(previousIndex < 0) M\?uDC9
return0; b6WC@j`*T
else 6|9g4@Hy
return previousIndex; ?<yq 2`\4O
} peTO-x^a-
cxP9n8CuT
} v1X&p\[d
r@ T-Hi
C@UJOB
S `m-5
抽象业务类 JX\T
{\m#
java代码: ;*g*DIR
H6PXx
!AD0-fZ
/** TA@tRGP>
* Created on 2005-7-12 ) (?UA$"
*/ H ?=pWB
package com.javaeye.common.business; '[=yfh
X4P}aC
import java.io.Serializable; ll<9f)
import java.util.List; z7t'6Fy9'
;oY(I7
import org.hibernate.Criteria; s7UhC.>'@
import org.hibernate.HibernateException; JJ
N(M*;
import org.hibernate.Session; BudWbZ5>Ep
import org.hibernate.criterion.DetachedCriteria; we H@S
import org.hibernate.criterion.Projections; A}#]g>L
import mSw?2ba
An8%7xa7
org.springframework.orm.hibernate3.HibernateCallback; =ve*g&
import \\2k}TsB
{sna)v$;
org.springframework.orm.hibernate3.support.HibernateDaoS y[^k*,=
9
]4 K1%ZV
upport; .n)!ZN
az\<sWb#
import com.javaeye.common.util.PaginationSupport; S-M)MCL
=mi:<q
public abstract class AbstractManager extends aX[1H6&=7
x'=3&vc4
HibernateDaoSupport { P+;CE|J`X
#A|D\IhF
privateboolean cacheQueries = false; L)R[)$2(g
^ =/?<C4
privateString queryCacheRegion; dxkRk#mf:
e$ XY\{
publicvoid setCacheQueries(boolean 22al
;Oi[:Ck
cacheQueries){ Hn#GS9d_?
this.cacheQueries = cacheQueries; "J8;4p
} ;Txv-lfS
u6iU[5
publicvoid setQueryCacheRegion(String 56bud3CVs
nI` f_sp
queryCacheRegion){ wZo.ynXT
this.queryCacheRegion = ~<2 IIR$H
5M<'A=
queryCacheRegion; ^8';8+$
} $IxU6=ajn
!y
qa?\v9
publicvoid save(finalObject entity){ mX<Fuu}E*Z
getHibernateTemplate().save(entity); AK@`'$
} m{bZRkt
n2xLgK=
publicvoid persist(finalObject entity){ Ss#@=:"P
getHibernateTemplate().save(entity); |P,zGy
} (
K6~Tj
`x{.z=xC
publicvoid update(finalObject entity){ Sc4obcw%
getHibernateTemplate().update(entity); N"Qg\PS_
} tT@w%Sz57N
MG7 ?N #
publicvoid delete(finalObject entity){ ~|y^\U@
getHibernateTemplate().delete(entity); }pl]9
} T}L^CU0
Ci7P%]9
publicObject load(finalClass entity, 5|<yfk8*J
eKZ@FEZ
finalSerializable id){ C%}]"0Q1
return getHibernateTemplate().load &dhcKO<4
k#axt
Sc
(entity, id); Snc;p
} 93W
.N~PHyXZR
publicObject get(finalClass entity, y*VQ]aJ
KA 5~">l
finalSerializable id){ AW,v
return getHibernateTemplate().get v`#j
,:#,}w_HyO
(entity, id); qj~flw1:
} mF[o*N*
(O)\#%,@R
publicList findAll(finalClass entity){ w/b>awI
return getHibernateTemplate().find("from z-EwXE
0>,.c2),
" + entity.getName()); g>2aIun_Q
}
0dgP
hpbwZ
publicList findByNamedQuery(finalString (C8 U
doP$N3Zm
namedQuery){ s?QVX~S"
return getHibernateTemplate \#4m@
?M *7@t@
().findByNamedQuery(namedQuery); gM4P j[W
} yfmp$GO:
IDy_L;'`*
publicList findByNamedQuery(finalString query, >5)<Uv$
D(y+1^>
finalObject parameter){
f~w>v
return getHibernateTemplate wP[xmO-%
j$3rJA%rN
().findByNamedQuery(query, parameter); %KGq*|GUu
} yJ!OsD
c |>=S)|
publicList findByNamedQuery(finalString query, 21r==
H$
T vrk^!
finalObject[] parameters){ (GCG/8s
return getHibernateTemplate K(<$.
8zhBA9Y#~
().findByNamedQuery(query, parameters); y }\r#"Z`
} rRB~=J"
\HAJ\9*w)
publicList find(finalString query){ sX+`wc
return getHibernateTemplate().find T4mv%zzS
q@(1Yivk
(query); z{ptm7
} 7;&(}
y|$R`P
publicList find(finalString query, finalObject *)u?~r(F
"\e:h|
.G
parameter){ $}t=RW
return getHibernateTemplate().find sLb8*fak
3sH\1)Zz
(query, parameter); g>so
R&*
} 9YB2e84j
!; IJ
public PaginationSupport findPageByCriteria 9A~>`.y
QV7,G9
(final DetachedCriteria detachedCriteria){ geksjVwPH
return findPageByCriteria ^YGTh0$W
Yc^%zxub
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?hnx/z+uT
} !O|ql6^;
3gAR4
public PaginationSupport findPageByCriteria xq}-m!nX
\[yr=X
(final DetachedCriteria detachedCriteria, finalint pz{'1\_+9
)zU:
startIndex){ ]*qU+&
return findPageByCriteria 8".2)W4*
LheFQ A
(detachedCriteria, PaginationSupport.PAGESIZE, $.pTB(tO
?WQNIX4
startIndex); $B\ H
} I,b9t\(6
6B0#4Qrv
public PaginationSupport findPageByCriteria Ga v"C{G
H$!+A
(final DetachedCriteria detachedCriteria, finalint nZfs=@w:y
U@'F%nHw
pageSize, owvS/"@
finalint startIndex){ fAGctRGH
return(PaginationSupport) yub{8 f;v
v5_7r%Hiw
getHibernateTemplate().execute(new HibernateCallback(){ "+)K |9T#
publicObject doInHibernate OOnX`
CK0l9#g
(Session session)throws HibernateException { 3X;{vO\a1
Criteria criteria = 8'A72*dhX
>H>gH2qp
detachedCriteria.getExecutableCriteria(session); [ $pmPr2
int totalCount = j(iuz^I
~:4~2d|
((Integer) criteria.setProjection(Projections.rowCount =. *98
`1Zhq+s
()).uniqueResult()).intValue(); B:<
]Hl$
criteria.setProjection y`yZR
_
kbYeV_OwM
(null); Bq@zaMv
List items = iib
LvcuZZ`1a
criteria.setFirstResult(startIndex).setMaxResults P ZxFZvE
]ab#q=
(pageSize).list(); XM/vDdR
PaginationSupport ps = Tkw;pb
lT'9u,6
new PaginationSupport(items, totalCount, pageSize, |Y},V_@d
1svi8wh
startIndex); \=;uu_v$
return ps; Ye5jB2Z
} wG1l+^p
}, true); Ts9ktPlm
} z
x@$RS+]
"7,FXTaer
public List findAllByCriteria(final ~>Kq<]3~
nPN?kO=]
DetachedCriteria detachedCriteria){ JN4fPGbV
return(List) getHibernateTemplate Ya#h'+}
paW@\1Q
().execute(new HibernateCallback(){ :=Kx/E:1
publicObject doInHibernate O/Rhf[7v*
KL [ek
(Session session)throws HibernateException { 5|I55CTx
Criteria criteria = G_ >G'2
.&1C:>
detachedCriteria.getExecutableCriteria(session); c)}2K0
return criteria.list(); #aar9
} AVl~{k|
}, true); M6rc!K
} Qd
&"BEs
9MY7a=5E~
public int getCountByCriteria(final L?5f+@0.
\(
)#e
DetachedCriteria detachedCriteria){ [8XLK 4e
Integer count = (Integer) ?kTWpXx"=
HN6}R|IH
getHibernateTemplate().execute(new HibernateCallback(){ El-
? %
publicObject doInHibernate e5?PkFV^a1
a.@qGsIH
(Session session)throws HibernateException { :7g=b%;
Criteria criteria = T6#CK
WC,+Cn e
detachedCriteria.getExecutableCriteria(session); `.%JjsD<
return !ABiy6d
rJJ[X4$
criteria.setProjection(Projections.rowCount vUA0FoOp
Sv'y e
()).uniqueResult(); l"(6]Z 4
} e`K)_>^n#
}, true); l@JSK;
return count.intValue(); lFSe?X^
} p|+B3
} dRi5hC$
B@y(.
<7_KeOLJ
::5E 8919
e@#kRklV&
%JZZ%xc
用户在web层构造查询条件detachedCriteria,和可选的 L<V3KS2y
+7V{ABfGl
startIndex,调用业务bean的相应findByCriteria方法,返回一个 zYY$D.
*sw7niw
PaginationSupport的实例ps。 O#a6+W"U
(X[CsaXt
ps.getItems()得到已分页好的结果集 N K]B?
ps.getIndexes()得到分页索引的数组 V 9wI\0
ps.getTotalCount()得到总结果数 m#vL*]c}
ps.getStartIndex()当前分页索引 w
Y
ps.getNextIndex()下一页索引 SqA
J-_~
ps.getPreviousIndex()上一页索引 A{ eL l
+rXF{@
l
E
Y<8B3y
sP@X g;]
b5G}3)'w
6K`c/)
`d]IX^;
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 cO2& VC
!4"^`ors$
,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 4+;$7"fJ
:O<bA&:d
一下代码重构了。 x%+{VStA
d[ >`")2)
我把原本我的做法也提供出来供大家讨论吧: g*UMG>
;<
jbLhHwD
首先,为了实现分页查询,我封装了一个Page类: Yap?^&GV
java代码: }@1q@xU
I){\0vb@
A-
YBQPE
/*Created on 2005-4-14*/ &,\=3'
package org.flyware.util.page; V
r(J+1@
N,dT3we
/** M 3 '$[
* @author Joa '_\;jFAM
* $''?HjB}T
*/ 2&'|Eqk
publicclass Page { D4Al3fe
`;|5
/** imply if the page has previous page */ ^9OUzTF
privateboolean hasPrePage; >_dx_<75&
"xmP6=1
/** imply if the page has next page */ M->*{D@a
privateboolean hasNextPage; VV4Gjc
%3q0(Xl
/** the number of every page */ /MMd`VrC2
privateint everyPage; Migd(uw'
u's`*T@.
/** the total page number */ kE8>dmH23
privateint totalPage; Wz4&7KYY
zya5Jb:Sg
/** the number of current page */ =gfI!w
privateint currentPage; ?"#%SKm
QxuhGA
/** the begin index of the records by the current n+@F`]Ke
n\Fp[9+Z\
query */ &AVpLf:?
privateint beginIndex; {t"+
3zy'
wbDM5%
FLg*R/
/** The default constructor */ )#|<w9uec
public Page(){ f<=Fsl
;*ix~taL%
} '7wd$rl
\!IMaB]
/** construct the page by everyPage 2sNK
* @param everyPage LMi:%i%\
* */ >Rvx[`|O!m
public Page(int everyPage){ g4`Kp;}&'
this.everyPage = everyPage; |(moWY=
} IK,|5] *Ar
:j|IP)-f
/** The whole constructor */ gqXS~K9t
public Page(boolean hasPrePage, boolean hasNextPage, 2!&&|Mh}
j'[m:/
nJ4@I7Sk;
int everyPage, int totalPage, gBT2)2]
int currentPage, int beginIndex){ 7 n]65].t
this.hasPrePage = hasPrePage; I;5R2" 3
this.hasNextPage = hasNextPage; 8[r9HC
this.everyPage = everyPage; )jWOP,|
this.totalPage = totalPage; [7(-T?_
this.currentPage = currentPage; O }9KJU
this.beginIndex = beginIndex; }$MN|s
} 3nT
Z)L }
\s3]_1F;t
/** +*\X]06
* @return JN^&S
* Returns the beginIndex. SN4Q))dAU
*/ `%+ mO88o
publicint getBeginIndex(){ xq6cKtSv
return beginIndex; ,+`61J3W
} (-]r~Ol^
-a*K$rnB
/** [I4ege>
* @param beginIndex 1/p*tZP8i
* The beginIndex to set. {G <kA(Lm
*/ QL6C,#6
publicvoid setBeginIndex(int beginIndex){ Kp+CH7I*
this.beginIndex = beginIndex; f.24:Dw,
} ~GE$myUT\p
=@TQ>Qw%b
/** o=FE5"t
* @return ,-x!$VqS
* Returns the currentPage. OD']:
*/ tXJUvish
publicint getCurrentPage(){ 2[0JO.K
4
return currentPage; ARcv;H 5
} w9
w%&{j
u77E! z4Uz
/** vI$t+m:
* @param currentPage >~`C-K#
* The currentPage to set. !`!| Zw
*/ _gKe%J&
publicvoid setCurrentPage(int currentPage){ PtqJ*Z
this.currentPage = currentPage; @EE."T9
} -hC,e/+
r`c_e)STO
/** >0p$(>N]
* @return b64
@s2]
* Returns the everyPage. $gBd <N9|c
*/ jx Jv.
publicint getEveryPage(){ }|%eCVB
return everyPage; ?g!V!VS2
} e#/E~r&
&rkEK4
/** D&HV6#
* @param everyPage hzk6rYg1
* The everyPage to set. p4p@^@<>X
*/ ~b{Gz6u>
publicvoid setEveryPage(int everyPage){ ;[RZ0Uy=
this.everyPage = everyPage; nx0K$Ptq
} E^U0f/5
m
sB69R:U;
/** 8w({\=
* @return ;gC|
* Returns the hasNextPage. fwzb!"!.@
*/ AkOO)0
publicboolean getHasNextPage(){ \.mI
return hasNextPage; <AJ97MLcc
} tGB@$UmfU
HHqwq.zIy
/** AyMd:5;
* @param hasNextPage ko5V9Drc
* The hasNextPage to set. []s^
*/ l }XU59
publicvoid setHasNextPage(boolean hasNextPage){ Z$J#|
this.hasNextPage = hasNextPage; dL|+d:v
} 0a"igq9t
!n^OM?.4
/** ?WE
* @return m|OO,gR
* Returns the hasPrePage. h$L"8#
*/ q&:=<+2"
publicboolean getHasPrePage(){ .xBu-?6s6
return hasPrePage; a1Qv@p^._b
} xeGb?DPu
\c^45<G2qA
/** y^o@"IYu3
* @param hasPrePage v9T_&
* The hasPrePage to set. v@# b}N0n
*/ 3]?#he
publicvoid setHasPrePage(boolean hasPrePage){ %Qk/_ R1
this.hasPrePage = hasPrePage; LkQX?2>]
} O9:U8$*
_#vrb;.+
/** Xy%p "b<
* @return Returns the totalPage. imiR/V>N
* 7 I>G{
*/ epgPT'^
publicint getTotalPage(){ sUPz/Z.h
return totalPage; @?"h
!fyu
} KN-avu_Ix
mS0udHod
/** }`+B=h-dW
* @param totalPage ``E/m<r:$
* The totalPage to set. h,"4SSL
*/
^eoLAL
publicvoid setTotalPage(int totalPage){ tnLAJ+-M
this.totalPage = totalPage; F`9]=T0
} $/nY5[
0?>dCu\
} yv)ux:P&+
d:yqj:
~Ch+5A;
[LRLJ_~g5
@gG<le6
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 ES40?o*]x
w|Nz_3tI
个PageUtil,负责对Page对象进行构造: IT$25ZF
java代码: \}]!)}G
2<}NB?f`N
n9s iX
/*Created on 2005-4-14*/ $ [yFsA6
package org.flyware.util.page; j!3 Gz
Uo2GK3nT
import org.apache.commons.logging.Log; ^%`wJ.c
import org.apache.commons.logging.LogFactory; |2KAo!PI
2YDM9`5xs\
/** U)3DQ6T99
* @author Joa fNrgdfo
* NssELMtF!g
*/ tr7<]Hm:
publicclass PageUtil { i E CrI3s
~/*MY
privatestaticfinal Log logger = LogFactory.getLog g(4xC7xK6
gJM`[x`T
(PageUtil.class); (T2m"Yi:
hqRw^2F
/** B,{K*-7)MX
* Use the origin page to create a new page MR}Agu#LG
* @param page ciMzf$+G$
* @param totalRecords K#"O
a
h
* @return &~W:xg(jN
*/ zk( U8C+
publicstatic Page createPage(Page page, int 2,*M|+W~
:^(>YAyHj^
totalRecords){ Qf@
return createPage(page.getEveryPage(), xNbPsoK
yiO.z
page.getCurrentPage(), totalRecords); F8apH{&t
} 50={%R
2p"WTd
/** p/h
Rk<K6
* the basic page utils not including exception 4R\Hpt
\eFR(gO+
handler ,TFIG^Dvq
* @param everyPage #t+d iR
* @param currentPage f%*/cpA)
* @param totalRecords 8]LD]h)B"
* @return page q`r**N+zn
*/ l'eyq}&
publicstatic Page createPage(int everyPage, int 6R^^ .tCs
RU\/j%^
currentPage, int totalRecords){ =AuR:Tx
everyPage = getEveryPage(everyPage); k1!@^A
currentPage = getCurrentPage(currentPage); cb}[S:&|
int beginIndex = getBeginIndex(everyPage, uS^Ipxe\
yeMB0Z*r
currentPage); ZMq6/G*fD
int totalPage = getTotalPage(everyPage, Gh}*q|Lz
ukUGvK
totalRecords); mWvl38
boolean hasNextPage = hasNextPage(currentPage, Q 7?#=N?
JeE;V![
totalPage); d N$Tf
boolean hasPrePage = hasPrePage(currentPage); E@b(1@
15sp|$&`
returnnew Page(hasPrePage, hasNextPage, /~<@ *-'
everyPage, totalPage, |)*fRL,
currentPage, q*9!,!e
aca=yDs2
beginIndex); &Udb9
} a0#J9O_
(I./ Uu%
privatestaticint getEveryPage(int everyPage){ }1upi=+aE
return everyPage == 0 ? 10 : everyPage; 1aTB%F
} :*KHx|Q
_FWBUZ;N
privatestaticint getCurrentPage(int currentPage){ U-3i
return currentPage == 0 ? 1 : currentPage;
w.TuoWo>
} =z
/dcC$r
@!1x7%]G
privatestaticint getBeginIndex(int everyPage, int BSVxN
BT"XT5@
currentPage){ PAM}*'
return(currentPage - 1) * everyPage; ^RI?ybDd
} u`RI;KF~F
tw9f%p
privatestaticint getTotalPage(int everyPage, int l~$+,U&XNe
IqoR7ajA
totalRecords){ y9Us n8
int totalPage = 0; sc,vj'r
)'+8}T]xQ
if(totalRecords % everyPage == 0) WA&!;Zq
totalPage = totalRecords / everyPage; #NryLE!/
else bXNk%W[n
totalPage = totalRecords / everyPage + 1 ; {Sj9%2'M)
H|HYo\@F#
return totalPage; av|g}xnj
} ?snp8W-WB
\}|o1Xh2
privatestaticboolean hasPrePage(int currentPage){ Sxh]R+Xb
return currentPage == 1 ? false : true; Iepsz
} jJPGrkr
4.5|2\[
privatestaticboolean hasNextPage(int currentPage, gK'1ZLdZ2
OD!& .%
int totalPage){
c$yk s
return currentPage == totalPage || totalPage == CTZ8Da^
O*FUTZd( J
0 ? false : true; 7x%R:^*4
} LHo3
Niy.
g0["^P1tV
d\gJ$ ~^K
} m3/O.DY%0
[UWdW
M# %a(Y3K)
z)r=+ -
E;R n`oxk
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。 /~$WUAh
abfW[J
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 /Y2}a<3&0
U ^5Kz-5.
做法如下: _ =VqrK7T
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 vkEiOFU!u
sW'2+|3"
的信息,和一个结果集List: +Z!)^j
java代码: .Z
`av n
x#xFh0CA
:Ra,Eu
/*Created on 2005-6-13*/ Xx0hc 8qd
package com.adt.bo; U"^kH|
,N]H dR
import java.util.List; \=ux atw
(G;lx
import org.flyware.util.page.Page; U`NjPZe5^
'9
[vDG~
/** %1xb,g KO
* @author Joa zv\kPfGDK
*/ OX?\<),
publicclass Result { n%.7h3
TU,s*D&e
private Page page; m!tbkZHQn0
m4hg'<<V
private List content; 7>))D'l57
b)qoh^
/** Ch|jtVeuyJ
* The default constructor f$Fhf?'
*/ R5-@
public Result(){ P"IPcT%Ob%
super(); %u5L!W&
} CFMo)"
RbP6F*f
/** '}Z~JYa0
* The constructor using fields Q/(K$6]j
* lvBx\e;7P
* @param page koZ*+VP=
* @param content jD<{t
*/ uXJ;A *
public Result(Page page, List content){ vZaZc}AyL
this.page = page; U4C 9<h&
this.content = content; 2a`o
&S
} L\xk:j1[
Ez
fN&8E
/** vyK7I%T'R
* @return Returns the content. (3Two}
*/ .*Ct bGw
publicList getContent(){ $j5K8Ad
return content; emqZztccZ
} 6z#acE1)M
t4zkt!`B
/** 9=8iy
w
* @return Returns the page. vgH3<pDiU6
*/ mGJKvJF
public Page getPage(){ 6;\I))"[
return page; (a.z9nqGA
} w[zjerH3
=hC,@R>;
/** 93("oBd[s(
* @param content [65`$x-
* The content to set. ~962i#&4
*/ ao1(]64X"
public void setContent(List content){ 8*#R]9
this.content = content; "55skmD.P
} RI
5yF
k;AD`7(=
/** Sq/
qu-%X
* @param page =jOv] /
* The page to set. c[wla<dO*
*/ aeFe!`F
publicvoid setPage(Page page){ 6}[I2F_^
this.page = page; A+ZK4]xb
} la0BiLzb]
} ([T>.s
"d#Y}@*~o
lT(WD}OS
V@e?#iz
&C,'x4c"
2. 编写业务逻辑接口,并实现它(UserManager, 7~^GA.92
oTU!R ,
UserManagerImpl) jnK WZ/R
java代码: y&q*maa[
Fq~yL!#!
m ZtCL
/*Created on 2005-7-15*/ #%iDT6
package com.adt.service; =9'RM>
9YIM'q>`v
import net.sf.hibernate.HibernateException; :~e>Ob[,"
R]c+?4J
import org.flyware.util.page.Page; I5 o)_nc
TJ_$vI
import com.adt.bo.Result; &=Ar
Z&Pg"a?\
/** bH7X'%r
* @author Joa jVv0ST*z
*/ ieDk ;
publicinterface UserManager { m[?E
|oH,
public Result listUser(Page page)throws #%a;"w
jaTh^L
HibernateException; 3oGt3F{gZ
'y;EhOwj,
} sT 3^hY7
-BrMp%C
_E &A{HkJ
8n#HFJ~
PWaw]*dFmy
java代码: A -H&
.b3Qfxc>
nrL9
E'F'
/*Created on 2005-7-15*/ /\ y?Y
package com.adt.service.impl; 3KRd
b3&zjjQ
import java.util.List; Y>|B;Kj0(
l4 D+Y
import net.sf.hibernate.HibernateException; ?{P"O!I{
@TLS<~
import org.flyware.util.page.Page; QwNly4
import org.flyware.util.page.PageUtil; !O+)sbd<
"cE7
5
import com.adt.bo.Result; dsb `xw
import com.adt.dao.UserDAO; ^=BTz9QM
import com.adt.exception.ObjectNotFoundException; 63q^ $I
import com.adt.service.UserManager; .Xfq^'I[
f/
?_
/** 9_q#W'/X
* @author Joa (Mo*^pVr
*/ KSbKEA
publicclass UserManagerImpl implements UserManager { y6ECdVF
7,U=Qe;
private UserDAO userDAO; prC;L*~8
%q/62f7?
/** V/%>4GYnC
* @param userDAO The userDAO to set. oibsh(J3
*/ oI0M%/aM
publicvoid setUserDAO(UserDAO userDAO){ [>+4^&
this.userDAO = userDAO; (7mAt3n
k
} (|[2J3ZET
@oNH@a
j%
/* (non-Javadoc) *? 5*m+
* @see com.adt.service.UserManager#listUser ;X8yFq
EY^1Y3D w0
(org.flyware.util.page.Page) opY@RJ]
*/ gFeO}otm
public Result listUser(Page page)throws +DW~BS3
j-4VB_N@
HibernateException, ObjectNotFoundException { AYt%`Y.!
int totalRecords = userDAO.getUserCount(); 3C?f(J}
if(totalRecords == 0) xHUsFms
throw new ObjectNotFoundException `n#H5Oyn
Pj#<K%Bz
("userNotExist"); Gy9$wH@8
page = PageUtil.createPage(page, totalRecords); ]mo-rhDsM
List users = userDAO.getUserByPage(page); eK6hS_E
returnnew Result(page, users); Fz3fwLawI
} 6%'.A]"
8UW^"4
} V@B__`y7
-|J"s$yO4
HKU~UTRnZ
nim*/LC[:
3p39`"~
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @KWb+?_H{<
H35S#+KX
询,接下来编写UserDAO的代码: J}htu
3. UserDAO 和 UserDAOImpl: 3/aMJR:o
java代码: x*![fK
B( ]M&
i'a?kSy
/*Created on 2005-7-15*/ .\[`B.Q
package com.adt.dao; xAqb\|$^
YNLV9.P6
import java.util.List; un)4eo!7
%j:]^vqFA
import org.flyware.util.page.Page; I3=%h
ge,H-8'Z
import net.sf.hibernate.HibernateException; O,J>/
E.r>7`E
/** /,89p&h
* @author Joa 1%EBd%`#
*/ #D<C )Q
publicinterface UserDAO extends BaseDAO { bP8Sj16q
O;z,qo X
publicList getUserByName(String name)throws V[{6e
CpA|4'#
HibernateException; qS403+Su1=
dq7x3v^"ZG
publicint getUserCount()throws HibernateException; bHPYp5UwN
CUO+9X-<8
publicList getUserByPage(Page page)throws ~c8?>oN(
@E^~$-J5j
HibernateException; ~;QvWS
3[\iQ*d }B
} J{l1nHQZSu
)hd@S9Z.Y
VCu{&Sh*
e&simX;W
*v;!-F&8>
java代码: c]$i\i#
qHsUP;7
k>F'ypm
/*Created on 2005-7-15*/ bBu,#Mc
package com.adt.dao.impl; us;YV<)d
y)F;zW<+
import java.util.List; _wC3kAO
?Eg(Gu.J
import org.flyware.util.page.Page; Q~814P8]
FqkDKTS\&
import net.sf.hibernate.HibernateException; `sUZuWL_
import net.sf.hibernate.Query; wHsYF`
3Vsc 9B"w
import com.adt.dao.UserDAO; #hW;Ju73
sSOOXdnGG
/** !$DIc
* @author Joa r>dwDBE
*/ _9faBrzd
public class UserDAOImpl extends BaseDAOHibernateImpl f_wvZ&
a#^B2
implements UserDAO { sJ#4(r`
/|r^W\DV&x
/* (non-Javadoc) =7-9[ {
* @see com.adt.dao.UserDAO#getUserByName e8y;.D[2
~hZ"2$(0
(java.lang.String) d{rQzia"mV
*/ Wc,_RN-
publicList getUserByName(String name)throws *7*lE"$p
y#>,+a#5
HibernateException { nnCGg+l
String querySentence = "FROM user in class ~1cnE:x;V
$@sEn4h
com.adt.po.User WHERE user.name=:name"; R#xCkl -
Query query = getSession().createQuery UQ8M~x5$3%
`kOD[*
(querySentence); y]2qd35u_A
query.setParameter("name", name); D5$wTI
return query.list(); Q<z_/j9
} ,%n\=
#?5 (o
/* (non-Javadoc) U3 */v4/
* @see com.adt.dao.UserDAO#getUserCount() @*}D$}aR'V
*/ -c(F 1l
publicint getUserCount()throws HibernateException { 0FGe=$vD
int count = 0; Uh.oErHQD
String querySentence = "SELECT count(*) FROM y@ ML/9X8q
hD\rtW
user in class com.adt.po.User"; 2GFLnz
Query query = getSession().createQuery pM x
|B.0TdF
(querySentence); _= +V/=
count = ((Integer)query.iterate().next ,pqGX3
`%CtWJ(e
()).intValue(); J+[_Wd
return count; "nZ*{uv
} wyp|qIS;
)u3 Zm
/* (non-Javadoc) .9R
[*<
* @see com.adt.dao.UserDAO#getUserByPage .nG#co"r}3
SPN5dE.@
(org.flyware.util.page.Page) "vXxv'0\f
*/ Tg!i%v(-t
publicList getUserByPage(Page page)throws W"):-Wq
!O-T0O
HibernateException { I'PeN0T
f
String querySentence = "FROM user in class F_Z- 8>P
;} und*q
com.adt.po.User"; kdCUORMK
Query query = getSession().createQuery kspTp>~
=jSb'Vu|
(querySentence); ;w:M`#2
query.setFirstResult(page.getBeginIndex()) Sczc5FG
.setMaxResults(page.getEveryPage()); JXCCTUO
return query.list(); ~3WM5 fv
} "[vu6 `m?
cU0s
p
} W.z;B<
gfsI6/Y
}-ftyl7
HOw-]JSP2
W- i&sUgy
至此,一个完整的分页程序完成。前台的只需要调用 k9$K}
cU ?0(z7
userManager.listUser(page)即可得到一个Page对象和结果集对象 f>aEkh6u9
)\sc83L
的综合体,而传入的参数page对象则可以由前台传入,如果用 b|cyjDMAA
hc~s"Atck
webwork,甚至可以直接在配置文件中指定。 >2~+.WePu
"
Om[~-31
下面给出一个webwork调用示例: .%.9n\b
java代码: KC(xb5x
Y
m<{<s T
(rkyW z
/*Created on 2005-6-17*/ ^\\Tx*#i
package com.adt.action.user; b'J'F;zh>
=0^Ruh
import java.util.List; dYSr4pb
]?3un!o3o
import org.apache.commons.logging.Log; Ul2R'"FB
import org.apache.commons.logging.LogFactory; AFc$%\s4
import org.flyware.util.page.Page; >y.%xK
QFg sq{
import com.adt.bo.Result; f@8>HCI
import com.adt.service.UserService; v3}L`dyh3
import com.opensymphony.xwork.Action; g0>,%b
{Z3dF)>
/** G2t;DN(
* @author Joa .mDM[e@'
*/ SG-'R1
J
publicclass ListUser implementsAction{ Sp7ld7c
!PrwH;
privatestaticfinal Log logger = LogFactory.getLog j7sKsbb
XK|R8rhg8`
(ListUser.class); _^el\
k$H%.l;E
private UserService userService; 2 Yp7
0{dz5gUde
private Page page; qw@puw@D
(q{Ck#+
privateList users; _<a7CCg
X@k`3X
/* |tv"B@`
* (non-Javadoc) \e!vj.PU
* 3 n'V\Hvz
* @see com.opensymphony.xwork.Action#execute() "I=\[l8t
*/ ([-|}
publicString execute()throwsException{ aYuD>rD
Result result = userService.listUser(page); C8vOE`U,J
page = result.getPage(); K'X2dG*
users = result.getContent(); ,y+$cM(
return SUCCESS; 5aln>1x>hn
} 0
;b[QRmy
<Q?a=4
/** ;9~6_@,@o
* @return Returns the page. E2cB U{x
*/ 9lGOWRxR)
public Page getPage(){ %{/%mJoX
return page; &}?$i7x5
} c)A{p
^|/](
/** Ee@4 %/v
* @return Returns the users. v.:3"<ur}
*/ ;=<-5;rI
publicList getUsers(){ $<^u^q37u
return users; "TUe%o
} Wm);C~Le
es>W$QKlo
/** [Z~ 2
* @param page +V{7")px6
* The page to set. oyNSh8c7c
*/ B Ce|is0
publicvoid setPage(Page page){ x7vctjM|
this.page = page;
BWrv%7
} OvUI@,Ef
I
j$lDJS
/** IBQ@{QB
* @param users qwK2WE%T
* The users to set. + J{0 E
*/ u{FDdR9<
publicvoid setUsers(List users){ (`6T&>(4
this.users = users; hUD7_arKF
} f{"8g"[[)(
!^v5-xO?rP
/** ovwQ2TuK
* @param userService zOV=9"~{
* The userService to set. m85WA
#
`
*/ Iw<j T|y)
publicvoid setUserService(UserService userService){ 6m VuyI
this.userService = userService; =7m}yDs6$
} M@3"<[g
} kN%MP6? J
eL4NB$Fb
25NTIzI@@
r}0\}~'?c
Y!WG)u5
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, nOQa_G]Gz
3SSm5{197
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 ?KITC;\\
>7roe []-|
么只需要: Wd0[%`dq
java代码:
*]h`KxuO
u7xDau(c
/'Pd`Nxl.
<?xml version="1.0"?> i 9g>9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 9}c8Xt^&