Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :xtXQza"-
N5a*7EJv+
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bbrXgQ`s+w
c-B
cA
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 ^$b Y,CE
-r-k_6QP
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 zT!drq: x
W[Ls|<Q
。 {phNds%
&*+'>UEe5
分页支持类: 0g+'/+Ho 4
q@[QjGj@
java代码: Y;?{|
_lamn}(x0
V5UF3'3;}
package com.javaeye.common.util; ["h5!vj
9I&xfvD,
import java.util.List; nih0t^m'
19w*!FGX
publicclass PaginationSupport { 7Zlw^'q$:L
wK?vPS
publicfinalstaticint PAGESIZE = 30; Tj:B!>>
,yiX# ;j
privateint pageSize = PAGESIZE; Mu+0<>
~ _/(t'9
privateList items; Qk:Y2mL
8fl`r~bqZ
privateint totalCount; ZrsBm_Rx
/;oX)]W
privateint[] indexes = newint[0]; "N`[r iq{
kqFP)!37
privateint startIndex = 0; '<"s \,
@7IIM{
public PaginationSupport(List items, int `@`CG[-9
3kybLOG
totalCount){ )h7<?@wv&
setPageSize(PAGESIZE); e )d`pQ6
setTotalCount(totalCount); <g$~1fa
setItems(items);
!2ZF(@C/
setStartIndex(0); ;U-jO &
} %nf6%@s
1`=nWy='
public PaginationSupport(List items, int k$blEa4
sB7#
~pA
totalCount, int startIndex){ Zy`m!]G]80
setPageSize(PAGESIZE); .%xn&3
setTotalCount(totalCount); 9Z4nAc
setItems(items); x(1:s|Uyp{
setStartIndex(startIndex); ~E17L]ete
} 3LOdj T
J
e"|efE
public PaginationSupport(List items, int KVclhT<F
y3@H/U{
totalCount, int pageSize, int startIndex){ ;ub;lh 3
setPageSize(pageSize); V<GHpFi0
setTotalCount(totalCount); X
$jWo@
setItems(items); ZOh`(})hy
setStartIndex(startIndex); QIG$z?
} EJMM9(DQ7
0XE4<U
publicList getItems(){ eA2@Nkw~)
return items; ofm#'7P 0
} -|$@-fY;
bCRV\myd`
publicvoid setItems(List items){ ,E S0NA
this.items = items; C5o#i*|
} >qnko9 V
wW>A_{Y
publicint getPageSize(){ M:Pc,
return pageSize; xF!,IKlBBp
} LSL/ZvSP
akp-zn&je
publicvoid setPageSize(int pageSize){ =$'6(aDH
this.pageSize = pageSize; f6hnTbJ
} I|qo+u)
h4fJvOk|!
publicint getTotalCount(){ p`olCp'
return totalCount; lXW%FH6c+
} u^^[Q2LDU}
BC^ :=
publicvoid setTotalCount(int totalCount){ M\uiq38
if(totalCount > 0){ 3lrT3a3vV
this.totalCount = totalCount; 11Q1AN
int count = totalCount / Ag-(5:
8\&X2[oAD
pageSize; XO.jl" xu
if(totalCount % pageSize > 0) slCx w$
count++; } Y12
indexes = newint[count]; n(1l}TJy
for(int i = 0; i < count; i++){ -*1d!
indexes = pageSize * f,U.7E
;17E(tl
i; _>&X\`D
} Yl
Zso2
}else{ ` Fa~
this.totalCount = 0; kMIcK4.MH
} ,0M_Bk"
} V(H1q`ao9
)}Hpi<5N
publicint[] getIndexes(){ B-*+r`@Bd
return indexes; Vh|*p&
} ^UP`%egR
*7uH-u"5d
publicvoid setIndexes(int[] indexes){ ZF!h<h&,
this.indexes = indexes; p_RsU`[
} l!D}3jD
>FeX<L
publicint getStartIndex(){ Cjn#00
return startIndex; h79}qU
} Ouk^O}W6
q}3`|'3
publicvoid setStartIndex(int startIndex){ rDdoOb]B
if(totalCount <= 0) x[
SDl(<@;
this.startIndex = 0; 7`*h2 mgY
elseif(startIndex >= totalCount) )8a~L8oN
this.startIndex = indexes =Qy<GeY
\j$&DCv
[indexes.length - 1]; G<L;4nA)
elseif(startIndex < 0) yuh *
this.startIndex = 0; ik)|{%!K]H
else{ X]ipI$'+C
this.startIndex = indexes /:cd\A}
ju8>:y8
[startIndex / pageSize]; 1KU!
tL
} Cwv9 a^
} l0|5t)jF-
\[;0KV_
publicint getNextIndex(){ 5?f ^Rz
int nextIndex = getStartIndex() + Akq2 d;
Z%gh3
pageSize; /!0={G
if(nextIndex >= totalCount) =>m<GvQz
return getStartIndex(); /T"+KU*
else pIc#L>{E
return nextIndex; z0d.J1VW
} 34f?6K1c
*IB4[6
publicint getPreviousIndex(){ pE`})/?\*
int previousIndex = getStartIndex() - D,k6$`
f[]dfLS"W
pageSize; H%[eV8
if(previousIndex < 0) C"y(5U)d
return0; dn&s*
else #NQMy:JHD)
return previousIndex; .j ?W>F
} !Z1@}`V&;
0j^Kgx
} B`EJb71^Xy
{B~QQMEow
9=s<Ld
ko!)s
抽象业务类 R!HXhQ
java代码: W~)}xy
y#`tgJ:
v_yw@
/** m&d|t>3<
* Created on 2005-7-12 @="Pn5<]C
*/ F/]2G^-
package com.javaeye.common.business;
\__i
kpuz]a7pK
import java.io.Serializable; 1s\Wtw:
import java.util.List; zOJ%}
)7hqJa-V
import org.hibernate.Criteria; Xu{1".\
import org.hibernate.HibernateException; ."g`3tVK
import org.hibernate.Session; &w\{TZ{
import org.hibernate.criterion.DetachedCriteria; .7J#_*NV
import org.hibernate.criterion.Projections; RTYvS5G
import <3nMx^
)Om*@;r(
org.springframework.orm.hibernate3.HibernateCallback; Ao 'l"-
import P1!qbFDv8
)705V|v
org.springframework.orm.hibernate3.support.HibernateDaoS Zj(AJ* r
VG5i{1
0
upport; 7P} W
*
9i:L&dN
import com.javaeye.common.util.PaginationSupport; 5=-Q4d
yNPVOp*
public abstract class AbstractManager extends IW5,7.
e1yt9@k,
HibernateDaoSupport { e[1hz_v
hDDn,uzpd
privateboolean cacheQueries = false; *;W+>W
I{|O "8
privateString queryCacheRegion; U4'#T%*
6bg
;q(*7
publicvoid setCacheQueries(boolean .'6gZKXY
7g^]:3f!
cacheQueries){ XPc^Tq
this.cacheQueries = cacheQueries; [NTzcSN.
} &$+AXzn
}{Pp]*I<A
publicvoid setQueryCacheRegion(String ./Xz}<($8
ROI7eU
queryCacheRegion){ ijv(9mR
this.queryCacheRegion = iqsCB%;5
g _9C*
queryCacheRegion; v&\Q8!r_
} w7L{_aom
b!t0w{^w
publicvoid save(finalObject entity){ kdiM5l70
getHibernateTemplate().save(entity); f_OQ./`
} \doUTr R
G[ PtkPSJ
publicvoid persist(finalObject entity){ #\{l"-
getHibernateTemplate().save(entity); E_rI?t^
} 4>
K42m
=jN.1}
publicvoid update(finalObject entity){ b=C*W,Q_#
getHibernateTemplate().update(entity); zpn9,,~u
} ,>a&"V^k
fgTg7 m
publicvoid delete(finalObject entity){ ^e,.
getHibernateTemplate().delete(entity); RNk\.}m
} k t#fMd$
u[;\y|75
publicObject load(finalClass entity, Q-oktRK
xK[ou'
finalSerializable id){ Oi.C(@^(
return getHibernateTemplate().load tAd%#:K
,L2ZinU:
(entity, id); l\H=m3Bg
} ~7w"nIs<c
,_ H:J.ik
publicObject get(finalClass entity, mthA4sz
n&4N[Qlv,
finalSerializable id){ C}j"Qi`
return getHibernateTemplate().get ZDJ`qJ8V
Vr)S{k-Q
(entity, id); =ZznFVJ`={
} dES"@?!^
&J]K3w1p
publicList findAll(finalClass entity){ Pbn*_/H
return getHibernateTemplate().find("from "]*&oQCI
lN)C2 2
" + entity.getName()); z|J_b"u4
} HVCe;eI
eb\K "ec"
publicList findByNamedQuery(finalString tKuwpT1Qc
"S]0
namedQuery){ 9<?M8_
return getHibernateTemplate 4"(Bu/24
EWhK0Vej=
().findByNamedQuery(namedQuery); 9rX&uP)j^#
} $99n&t$Y
`{h*/Q
publicList findByNamedQuery(finalString query, D/gw .XYL
.hb:s,0mP
finalObject parameter){ 5V~oIL
return getHibernateTemplate C
82omL
xIW3={b 3
().findByNamedQuery(query, parameter); wU36sCo
} Vm(y7}Aq{
Ml{,
publicList findByNamedQuery(finalString query, p`dU2gV
2 a)xTA#
finalObject[] parameters){ FX&~\kmV'j
return getHibernateTemplate 6Pnjmw.HV
1-uxC^u?|#
().findByNamedQuery(query, parameters); :S83vE81WK
} Ta0|+IYk<
4Z=_,#h4.
publicList find(finalString query){ >2)OiQ`zg
return getHibernateTemplate().find #Vt%@*
i
Jt<_zn_FG
(query); NNR`!Pty
} qr^3R&z!}
xt*
3'v
publicList find(finalString query, finalObject nHAS(
{]!mrAjD
parameter){ f}ji?p
return getHibernateTemplate().find {lDd.Fn
2]jn '4
(query, parameter); pj{`';
:g
} XEp{VC@=
wssRA?9<
public PaginationSupport findPageByCriteria n)-$e4u2
{6|G@""O
(final DetachedCriteria detachedCriteria){ On:il$MU
return findPageByCriteria u%KTNa0
'F3f+YD
(detachedCriteria, PaginationSupport.PAGESIZE, 0); D/xbF`
} TER=*"!
ZF8 yw(z
public PaginationSupport findPageByCriteria 7IH@oMvE
(N6i4
g6
(final DetachedCriteria detachedCriteria, finalint kZ
.gO
sf
qL|8
startIndex){ \ a<h/4#|
return findPageByCriteria k,6f
/4V#C-
(detachedCriteria, PaginationSupport.PAGESIZE, "Yv_B3p
.V/Rfq
startIndex);
.GXBc
} =[{i{x|Qz
Gr'
CtO
public PaginationSupport findPageByCriteria 1CD+B=pQG
34O
`@j0-3
(final DetachedCriteria detachedCriteria, finalint 4r#= *
85$m[+md
pageSize, 8I?Wt
W
finalint startIndex){ bdrg(d6
return(PaginationSupport) S~bOUdV
Z
.t-4o<7 3
getHibernateTemplate().execute(new HibernateCallback(){ VBGuC c/
publicObject doInHibernate 9';JXf$
G@\1E+Ip
(Session session)throws HibernateException { &j`} vg
Criteria criteria = ".V$~n(
k68T`Ub\W6
detachedCriteria.getExecutableCriteria(session); sN*N&XG
int totalCount = ;(/ZO%h
W~;`WR;.
((Integer) criteria.setProjection(Projections.rowCount Lc,Pom
) 1f~ dR88
()).uniqueResult()).intValue(); Q#X8u-~
criteria.setProjection K~{$oD7!
AaOuL,l
(null); `/XY>T}-
List items = QB uMJm
Ad8n<zt|
criteria.setFirstResult(startIndex).setMaxResults ^7U
G$A
;>yxNGV`
(pageSize).list(); &*,#5.
PaginationSupport ps =
hoUD;3
.-c4wm}
new PaginationSupport(items, totalCount, pageSize, =E4LRKn
7
:x fPx
startIndex); "Mn6U-
return ps; /QWvW=F2<
} C*_C;6.~Y
}, true); 5E;qM|Ns
} w^|*m/h|@u
VcO0sa f`
public List findAllByCriteria(final Gbr=+AT
,t?B+$E
DetachedCriteria detachedCriteria){ |(E
FY\
return(List) getHibernateTemplate rC% *$g $
O)*+="Rg
().execute(new HibernateCallback(){ O!#g<`r{K
publicObject doInHibernate uAJx.>$b
T{.pM4Hd
(Session session)throws HibernateException { ?m}s4a
Criteria criteria = 3>AMII
4y?n
[/M/
detachedCriteria.getExecutableCriteria(session); u(>^3PJ+
return criteria.list(); p!7FpxZY
} !qh]6%l
}, true); ,{u
yG:
} '(f* 2eE:
A@[o;H}XP
public int getCountByCriteria(final @ $ ;q;
hHGoP0/o
DetachedCriteria detachedCriteria){ >}8j+t&T
Integer count = (Integer) Lv;^My
}<v@01
getHibernateTemplate().execute(new HibernateCallback(){ 5y[Oj^
publicObject doInHibernate i Dp)FQ$
D9=KXo^
(Session session)throws HibernateException { eK?MKe
Criteria criteria = t7Iv?5]N
HZC"nb}r4
detachedCriteria.getExecutableCriteria(session); |!3DPA(_
return N=5a54!/
w!-gJmX>
criteria.setProjection(Projections.rowCount Z,
Yb&b
8B
K(4?gC
()).uniqueResult(); qFCOUl
} %9F([K
}, true); wx=
$2N6
return count.intValue(); ?}tFN_X"
} *=/ { HvJ
} Cazocq5
@sW24J1q+
x_N'TjS^{
(l~AV9!m:
RUnSC OdX
#uG%j
用户在web层构造查询条件detachedCriteria,和可选的 Eex~xiiV
mI-]/:
startIndex,调用业务bean的相应findByCriteria方法,返回一个 {M4gF8(M
UT~4x|b:O
PaginationSupport的实例ps。 [I,Z2G,Jb
OUPUixz2Z
ps.getItems()得到已分页好的结果集 {l1.2!
ps.getIndexes()得到分页索引的数组 ifMRryN4
ps.getTotalCount()得到总结果数 2>xF){`
ps.getStartIndex()当前分页索引 np"\19^
ps.getNextIndex()下一页索引 X;
\+<LE
ps.getPreviousIndex()上一页索引 &ZlVWK~v
=vCY?I$P
u"cV%(#
*e TqVG.
{0Yf]FQb-a
y*jp79G
jjB~G^n
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h,u,^ r
PB\(=
,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 B[Ku\A6&
)1J R#
一下代码重构了。 n`B:;2X,
Ct <udO
我把原本我的做法也提供出来供大家讨论吧: Pe_W;q.
z;,u}u}aI
首先,为了实现分页查询,我封装了一个Page类: ul6]!Iy
java代码: v!-/&}W)1
36&e.3/#
F4-$~v@
/*Created on 2005-4-14*/ +aCv&sg
package org.flyware.util.page; w>s,"2&5J
.GPT!lDc
/** YNyk1cE
* @author Joa j?3wvw6T
* T"}5}6rSG
*/ XSwl Tg
publicclass Page { ?|\ER#z
[\98$BN
/** imply if the page has previous page */ E!)xj.aS$
privateboolean hasPrePage; (&Kk7<#`
5FPM`hLT
/** imply if the page has next page */ &v/dj@
privateboolean hasNextPage; 4<w.8rR:A
JQ_sUYh~3
/** the number of every page */ +;(c:@>@,
privateint everyPage; twHVv
,h m\
/** the total page number */ YlJ@XpKM
privateint totalPage; `iFmrC<
<y('hI'
/** the number of current page */ Wq D4YGN
privateint currentPage; 2G& a{
9rA0lqr]5
/** the begin index of the records by the current '5#^i:
hohfE3rd
query */ 7FP*oN?
privateint beginIndex; 2. NN8PPD"
DZ3wCLQtK
V# }!-Xj
/** The default constructor */ }1L4"}L.
public Page(){ *k7+/bU~~
+5g_KS
} a_^\=&?'
xC?6v'
/** construct the page by everyPage ]Grek<
* @param everyPage :".ARCg
* */ ]`!>6/[
public Page(int everyPage){ ,a{P4Bq
this.everyPage = everyPage; ;IvY^(YS@;
} 7JD' )
?8H8O %Z8
/** The whole constructor */ G/y5H;<9M
public Page(boolean hasPrePage, boolean hasNextPage, ]!W=^!
A_"w^E{P
U|H=Y"pL
int everyPage, int totalPage, 6##_%PO<m
int currentPage, int beginIndex){ ;0]aq0_#(
this.hasPrePage = hasPrePage; xk9%F?)
this.hasNextPage = hasNextPage; IEL%!RFG
this.everyPage = everyPage; */5d>04
this.totalPage = totalPage;
7~G9'P<
this.currentPage = currentPage; .Bl\Z
this.beginIndex = beginIndex; XFVE>/H
} KC*e/J
v|)4ocFK
/** 1W
c=5!
* @return n K1Slg#U
* Returns the beginIndex. >mbHy<<
*/ 9d0@wq.
publicint getBeginIndex(){ =g7x'
kN
return beginIndex; ;Zcswt8]u
} ih-#5M@
gMi0FO'
/** ]\-A;}\e
* @param beginIndex ch*8B(:
* The beginIndex to set. &@X<zWg
*/ { T/[cu<
publicvoid setBeginIndex(int beginIndex){ T=
8 0,
this.beginIndex = beginIndex; \i>?q
} Fk&c=V;SU
W<h)HhyG
/** k&M;,e3v6
* @return {r,.!;mHu
* Returns the currentPage. ]? c
B:}
*/ (fH#I tf
publicint getCurrentPage(){ [~+wk9P
return currentPage; 2"v6
>b%
} >>4qJ%bL
+)AG*
/** aL\PGdgO
* @param currentPage C!O0xhs
* The currentPage to set. ^x ]r`b
*/ (q/e1L-S
publicvoid setCurrentPage(int currentPage){ i'<[DjMDlm
this.currentPage = currentPage; 9Z$"K- G
} F@D`N0Pte
\{_q.;}
/** RT4x\&q
* @return d"1]4.c
* Returns the everyPage. V5@:#BIs
*/ `GBW%X/
publicint getEveryPage(){ +uF>2b6'
return everyPage; Gm&Za,4%4
} df8k7D;~e
l ~"^7H?4e
/** @-07F,'W,
* @param everyPage @(w@e\Bq
* The everyPage to set. o+iiSTJEe
*/ 7DogM".}~Q
publicvoid setEveryPage(int everyPage){ ~Y[r`]X`"m
this.everyPage = everyPage; Df-DRi
} /obfw^
a@K%06A;'
/** fCd&D
* @return @Rze|
T.
* Returns the hasNextPage. ;J( 8
L
*/ Rxt^v+ ,$
publicboolean getHasNextPage(){ 88O8wJN
return hasNextPage; ]"As1"
} r.=K~A
R{`(c/%8
/** 6?gW-1mY
* @param hasNextPage q4h]o^ +
* The hasNextPage to set. x3=A:}t8
*/ FW;?s+Uyx
publicvoid setHasNextPage(boolean hasNextPage){ 'T;P;:!\
this.hasNextPage = hasNextPage; {_"<1C
} Wx%H%FeK
kOrZv,qFG[
/** _#E0g'3
* @return {GT*ZU*
* Returns the hasPrePage. bn&TF3b
*/ bTNgjc
publicboolean getHasPrePage(){ (62"8iD6
return hasPrePage; w>&aEv/f
} / y40(l?
\[i1JG
/** `,*3[
* @param hasPrePage [ZwjOi:)
* The hasPrePage to set. lN
4oW3QT
*/ tmYz R%i
publicvoid setHasPrePage(boolean hasPrePage){ y3Qsv
this.hasPrePage = hasPrePage; ha<[bu e
} #pow ub
e;q!6%
/** J7$5s
* @return Returns the totalPage. ,5p(T_V/
* mfn,Gjt3O
*/ %)8}X>xq
publicint getTotalPage(){ {%5eMyF#
return totalPage; ?3`UbN:
} :K,i\
T@B/xAq5!
/** /N10
* @param totalPage x_Y!5yg
E
* The totalPage to set. H [\o RId
*/ oG?Xk%7&\
publicvoid setTotalPage(int totalPage){ _Kf% \xg
this.totalPage = totalPage; 3AtGy'NTp
} <?.&^|kS
rl;~pO5R9
} yjX9oxhtL
K&]G3W%V
Hyl%mJ
.p3,O6y2(F
3BJ0S.TF
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Xza(k
(*'f+R`$
个PageUtil,负责对Page对象进行构造: &-6Gc;f8
java代码: 2 c{34:
9ULQrq$?
S!CC
}3zw
/*Created on 2005-4-14*/ WIxy}3_to
package org.flyware.util.page; qS$Ox?Bw#u
(NU
NHxi5B
import org.apache.commons.logging.Log; V! A~K
import org.apache.commons.logging.LogFactory; prF%.(G2)
&i6mW8l
/** $szqy?i0?
* @author Joa 5r|,CQ7o
* ~rKrpb]ow
*/ I; |B.j
publicclass PageUtil { s Y Qk
%/.b~|,-
privatestaticfinal Log logger = LogFactory.getLog lT?v^\(H
x~~|.C,
(PageUtil.class); wKxtre(v
dn+KH+v
/** s} ;{ZAtE
* Use the origin page to create a new page ?Ep [M:,q
* @param page K=k"a
* @param totalRecords n
M*%o-
* @return }2.`N%[
*/ /nNN,hz
publicstatic Page createPage(Page page, int J=I:CD%
Y"aJur=`
totalRecords){ Vn}0}Jz
return createPage(page.getEveryPage(),
?P`K7
AjMh,@
page.getCurrentPage(), totalRecords); oW*16>IN9l
} 0R'?~`aTt
!)0;&e5
/** d.d/<
* the basic page utils not including exception vJ[^K
6ojo :-%Vf
handler ?M9=yA
* @param everyPage ChPmX+.i_
* @param currentPage v MH
* @param totalRecords :q%M_
* @return page #rfiD%c
*/ UECK:61Me
publicstatic Page createPage(int everyPage, int f+,qNvBY/
[!#L6&:a8
currentPage, int totalRecords){ w-MCZwCr)
everyPage = getEveryPage(everyPage); q"8ea/
currentPage = getCurrentPage(currentPage); K=h9Ce
int beginIndex = getBeginIndex(everyPage, /]Md~=yNp
h2]P]@nW;W
currentPage); xj;H&swo
int totalPage = getTotalPage(everyPage, ~IBP|)WA-
qiBVGH
totalRecords); :>f )g
boolean hasNextPage = hasNextPage(currentPage, @,7GaK\
Ai?*s%8v
totalPage); ,Uqs1#r
boolean hasPrePage = hasPrePage(currentPage); joAv{Tc
f+)L#>Gl?
returnnew Page(hasPrePage, hasNextPage, C1n>M}b
everyPage, totalPage, 04P}-L,
currentPage, ,j_i?Ff
!``,gExH
beginIndex); u^I|T.w<r6
} j-}O0~Jz
<^jQo<kU
privatestaticint getEveryPage(int everyPage){ '4Bm;&6M
return everyPage == 0 ? 10 : everyPage; EUX\^c]n
} O;jrCB
aSQ#k;T[
privatestaticint getCurrentPage(int currentPage){ FGmb<z 2p
return currentPage == 0 ? 1 : currentPage; Z0", !6nS
} R.1.)P[
,<P
vovg_
privatestaticint getBeginIndex(int everyPage, int 4p;`C
:J&oX
<nF^
currentPage){ Ka
V8[|Gn,
return(currentPage - 1) * everyPage; #f]SK[nR
} s-Tv8goNV
Moza".fiN
privatestaticint getTotalPage(int everyPage, int H40p86@M
XK@E;Rv
totalRecords){ HBXOjr<,{
int totalPage = 0; D'DfJwA
v$wIm, j
if(totalRecords % everyPage == 0) ;'@9[N9
totalPage = totalRecords / everyPage; 0=1T.4+=
else m&,(Jla
totalPage = totalRecords / everyPage + 1 ; `d`T*_
^Y \"}D
return totalPage; d^
8ZeC#
} u `6:5k
!z3jTv
privatestaticboolean hasPrePage(int currentPage){ Cnh \%OW
return currentPage == 1 ? false : true; X5$ Iyis
} xY(*.T9K
6?Ji7F
privatestaticboolean hasNextPage(int currentPage, @K!T,U
Aw.qK9I
int totalPage){ 0 /U{p,r6`
return currentPage == totalPage || totalPage == o3P${Rq
h3
}OX{k
0 ? false : true; ?%[@Qb=2
} '7@zGk##(
Lnl=.z`jK
T:yE(OBf
} Eo]xNn/g
v PG},m~-
4>e&f&y~
c<Tf
2]vZE
7ZWgf"1j
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。 y766;
X:J
lq;Pch
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 8'io$6d=
v`Oc,
做法如下: c,+:i1IAy
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'I6i,+D/q
M%P:n/j
的信息,和一个结果集List: )1`0PJoHE
java代码: aj{Y\
3L
m~0/&RA
$B5aje}i
/*Created on 2005-6-13*/ tFOhL9T
package com.adt.bo; w+u3*/Zf
-X2Buz8
import java.util.List; |t#)~Oo
I:1C8*/
import org.flyware.util.page.Page; U8n V[
M-Y_ Wb3
/** !wh8'X*
* @author Joa =MDysb&:
*/ ],Do6
@M-
publicclass Result { P{lB50
sWnLEw
private Page page; G3AesTT|
v;D~Pa
private List content; YO}<Ytx
/!XVHkX[
/** LBDjIpR6
* The default constructor ')<hON44EX
*/
_
*Pf
public Result(){ +Q"4Migbe@
super(); VQOezQs\
} >@
.
&Hs!:43E-<
/** 3{sVVq5Y
* The constructor using fields T'Dv.h
* [2M'PT3
* @param page T%*D~=fQ'
* @param content ]2qo+yB
*/ uiR8,H9*M
public Result(Page page, List content){ DT&@^$?
this.page = page; LsU9 .
this.content = content; bdE[;+58
} ZyFjFHe+
z 1X` o
/** <*cikXS
* @return Returns the content. RPL:-
*/ P.9>z7l{
publicList getContent(){ lA8`l>I
return content; ]Gq !`O1
} :P0mx
-r]W
/** _L=h0H l
* @return Returns the page. oE]QF.n#
*/ AFE~
v\Gz
public Page getPage(){ d<P\&!R(
return page; hv>\gBe i
} _u QOHwn
8&b,qQ~
/** O)r4?<Q
* @param content WOL:IZX%
* The content to set. L$M9w
*/ cTT L1SW
public void setContent(List content){ v0.#Sl-
this.content = content; BR;D@R``}
} t'k$&l}+
3AN/
H
/** XUuN )i
* @param page $*=<Yw4
* The page to set. bY~pc\V:`w
*/ 'E""amIJ
publicvoid setPage(Page page){ oe-\ozJ0
this.page = page; L)
T (<
} Qh\60f>0
}
H6/$d
[S!/E4>['
q^<?]8
.U]-j\
^Xh^xL2cn
2. 编写业务逻辑接口,并实现它(UserManager, -PR N:'T
v mk2{f,g
UserManagerImpl)
r3UUlR/Do
java代码: ln
dx"prW
^^D0^k!R
F0@gSurg)
/*Created on 2005-7-15*/ k\?Ii<m
package com.adt.service; &0JI!bR(
k@W1-D?
import net.sf.hibernate.HibernateException; U&p${IcEm
O6^]=/wd
import org.flyware.util.page.Page; : eVq#3}
A6(/;+n
import com.adt.bo.Result; ,Ko!$29[
H"WprHe
/** hkQ"OsU
* @author Joa &^Q/,H~S
*/ c\AfaK^KF
publicinterface UserManager { ;u)I\3`*!
$*fMR,~t&
public Result listUser(Page page)throws |@4' <4t
7hPY_W
y
HibernateException; zy
}$i?
v`1M[
} 1p=]hC
xU`p|(SS-
H9e<v4c
2[02,FG
\bw2u!
java代码: #AQV(;r7@
8bld3p"^
~b8]H|<'Y
/*Created on 2005-7-15*/ P/_['7
package com.adt.service.impl; j&qub_j"xX
}*]-jWt1J\
import java.util.List; gRcQt :
(SAs-
import net.sf.hibernate.HibernateException; [d]9Oa4
{R`[kt
import org.flyware.util.page.Page; P~X2^bw
import org.flyware.util.page.PageUtil; Z(CkZll
}0Ed]
import com.adt.bo.Result; e$rZ5X
import com.adt.dao.UserDAO; b d!Y\OD
import com.adt.exception.ObjectNotFoundException; },-H"Qs
import com.adt.service.UserManager; Pe3o;mx
X=&KayD
/** hp|YE'uYT
* @author Joa I%KYtv~`
*/ e+fN6v5pU
publicclass UserManagerImpl implements UserManager { NK
H@+,+V
ysY*k` 5
private UserDAO userDAO; /N.U/MPL_
5`p.#
/** uoh7Sz5!^
* @param userDAO The userDAO to set. ]:J$w]\
*/ AFwdJte9e
publicvoid setUserDAO(UserDAO userDAO){ +mT_QsLEv
this.userDAO = userDAO; |+D!=
:x
} KoT%Mfu
FfT`;j
/* (non-Javadoc) Wmv#:U
* @see com.adt.service.UserManager#listUser SXP]%{@R/
am6L8N
(org.flyware.util.page.Page) iDqoa\
*/ _6vWF
public Result listUser(Page page)throws dG ?*y
]3Sp W{=^(
HibernateException, ObjectNotFoundException { 7WzxA=*#
int totalRecords = userDAO.getUserCount(); )zDCu`
if(totalRecords == 0) &wDs6xq
throw new ObjectNotFoundException o-B$J?
X|]AT9W
("userNotExist"); >Cq<@$I2EB
page = PageUtil.createPage(page, totalRecords); mj7#&r,1l
List users = userDAO.getUserByPage(page); 5*u+q2\F
returnnew Result(page, users); =>~:<X.,
} E|shs=I
8P\Zo8}v
} W ]8QM1$
j8:\%|
Dk5 1z@
kvu)y`
M x"\5i
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5146kp|1
mgU<htMr1
询,接下来编写UserDAO的代码: 5L}/&^E#p
3. UserDAO 和 UserDAOImpl: W=+ Y|R!
java代码: m+z&Q
@d1Q"9}B
+k R4E23:
/*Created on 2005-7-15*/ qwAT>4
package com.adt.dao; &m;*<}X
Bdpy:'fJn
import java.util.List; l,aay-E
V0 a3<6@4
import org.flyware.util.page.Page; w7&A0M
k$:|-_(w
import net.sf.hibernate.HibernateException; t4-[Z$n5
TIg3`Fon
/** B^}yo65I
* @author Joa {R{=+2K!|k
*/ _Y m2/3!
publicinterface UserDAO extends BaseDAO { v4 E}D
6Q5^>\Y
publicList getUserByName(String name)throws +:/%3}`
:7;@ZEe
HibernateException; H3oFORh
"_?nN"A7
publicint getUserCount()throws HibernateException; VuZr:-K/
%E;'ln4h&,
publicList getUserByPage(Page page)throws Qn2&nD%zi
buHJB*?9
HibernateException; Q22 GIr
Q\0'lQJdy
} E' uZA
*/S_Icf
Ab;.5O$y
NvX[zqNP_R
E _|<jy$`
java代码: )D%~`,#pQ
@IZnFHN
:.`2^
/*Created on 2005-7-15*/ u9p$YJ
package com.adt.dao.impl; j![\& z
ql~J8G9
import java.util.List; %J-GKpo/S
e&>2
n
import org.flyware.util.page.Page; F_P~x(X
3o/[t
import net.sf.hibernate.HibernateException; :[d9tm
import net.sf.hibernate.Query; b|(:[nB
|JsZJ9W+J
import com.adt.dao.UserDAO; Y}KNKO;
`kSZX:=};
/** `XDl_E+>l
* @author Joa RT8 ?7xFc
*/ G^@5H/)
public class UserDAOImpl extends BaseDAOHibernateImpl M )(DZ}
Z4bNV?OH
implements UserDAO { LFV%&y|L
05 ^h"
/* (non-Javadoc) /BL4<T f
* @see com.adt.dao.UserDAO#getUserByName tX~w{|k
cm+P]8o%{
(java.lang.String) i"=\d
*/ 1=v*O.XW`
publicList getUserByName(String name)throws =-Ck4e *T
62NsJ<#>
HibernateException { PQE=D0
String querySentence = "FROM user in class DVeE1Q
A]3k4DLYS
com.adt.po.User WHERE user.name=:name"; \GU<43J2uo
Query query = getSession().createQuery b\5F ]r
!bP@n
(querySentence);
{K!)Ss
query.setParameter("name", name); TkF[x%o
return query.list(); bW:!5"_{H
} )LCHy^'
MWh6]gGs
/* (non-Javadoc) W}ofAkF
* @see com.adt.dao.UserDAO#getUserCount() -tU'yKhn
*/ ?&uu[y
publicint getUserCount()throws HibernateException { =i3n42M#
int count = 0; !ubD/KE
String querySentence = "SELECT count(*) FROM lmhLM. 2
2 ? 4!K.
user in class com.adt.po.User"; :~SyL !
Query query = getSession().createQuery J9 I:Q<;
_(zG?]y0P
(querySentence); G KeU%x
count = ((Integer)query.iterate().next 2>59q$|
-ze J#B)C
()).intValue(); R^e'}+Z
return count; CU~PT.
} IvNT6]6 P
iJ|uvPCE
/* (non-Javadoc) K|s,ru
* @see com.adt.dao.UserDAO#getUserByPage Y\hBd$lQ~
6E}qL8'5x
(org.flyware.util.page.Page) .c cp
*/ V G~Vs@c(
publicList getUserByPage(Page page)throws :MDKC /mC
@KUWxFak
HibernateException { = WJNWt>
String querySentence = "FROM user in class EBmt9S
nT)vNWT=
com.adt.po.User"; 8JUwf
Query query = getSession().createQuery 4`=mu}Y2
`qwBn=
(querySentence); +W+|%qM,\
query.setFirstResult(page.getBeginIndex()) {Hk}Kow
.setMaxResults(page.getEveryPage()); <\S:'g"(
return query.list();
W!(LF7_!
} "^iYLQOC
&Hnz8Or!
} FE;x8(;W8
uvS)8-o&F
E<*xx#p
S`]k>'
l
"J3x_~,[4m
至此,一个完整的分页程序完成。前台的只需要调用 ,v}k{( 16{
J|rq*XD}q
userManager.listUser(page)即可得到一个Page对象和结果集对象 -|9=P\U8S
\lNN Msd&
的综合体,而传入的参数page对象则可以由前台传入,如果用 v(%*b,^
-H-~;EzU
webwork,甚至可以直接在配置文件中指定。 rU(+T0t?I
0Y5_PTWb+Y
下面给出一个webwork调用示例: Uoix
java代码: BfiD9ka-z
~7Ux@Sx;
yEQs:v6L~
/*Created on 2005-6-17*/ 9-m=*|p
package com.adt.action.user; ^LzF@{ G
_h1mF<\ X^
import java.util.List; 7 Fsay+a
@9|hMo
import org.apache.commons.logging.Log; PeEj&4k
import org.apache.commons.logging.LogFactory; U,1-A=Og{o
import org.flyware.util.page.Page; ={Qi0Pvt
|
VDV<g5h
import com.adt.bo.Result; IO:G1;[/2L
import com.adt.service.UserService; Y\'}a+:@Ph
import com.opensymphony.xwork.Action; +x}<IS8
?|Zx!z ($
/** X#;bh78&-
* @author Joa Ilm^G}GB
*/ Rbv;?'O$L
publicclass ListUser implementsAction{ "-V"=t'
?!/kZM_ts
privatestaticfinal Log logger = LogFactory.getLog %vi83%$'4
BING{ew
(ListUser.class); El"Q'(:/U
zT-_5uZQ
private UserService userService; KJZ4AWH`
ENY+^7
private Page page; BTrn0
,UE83j8D^
privateList users; P=G3:eX
uWE^hz"
/* lks!w/yCF
* (non-Javadoc) 8, >P
* d m%8K6|
* @see com.opensymphony.xwork.Action#execute() ;i:d+!3XwC
*/ QkC(uS
publicString execute()throwsException{ q'MZ R'<@
Result result = userService.listUser(page); ;gr9/Vl
page = result.getPage(); IIx#2r
users = result.getContent(); uY'HT|@:{
return SUCCESS; 7. ;3e@s
} y"wShAR
-z(+/ /K:#
/** )w%!{hn
* @return Returns the page. R*r#E{!V;
*/ S|+o-[e8O
public Page getPage(){ 8}| (0mC
return page; r]36zX v
} jrh43
\$*
v|2T%y_
u
/** UFuX@Lu0
* @return Returns the users. $iz|\m
*/ 4+ Z]3oIRE
publicList getUsers(){ 5/Uy{Xt
return users; 0{ R=9wcc
} '2^Q1{ :\
6)Lk-D
/** :9 ^*
^T
* @param page kMd.h[X~
* The page to set. k$^`{6l
*/ `PH{syz
publicvoid setPage(Page page){ VW4r{&rS
this.page = page; B^9j@3Ux
} czd~8WgOa
u;c?d!E
/** h'F=YF$o
* @param users {/:x5l8
* The users to set. Z?QC!bWb
*/ +K4}Dmg
publicvoid setUsers(List users){ #;nYg?d=
this.users = users; [cp+i^f
} J/*`7Pd
n?Nt6U
/** 92KRb;c
* @param userService }`~+]9<
* The userService to set. |
%Vh`HT
*/ XOS[No~
publicvoid setUserService(UserService userService){ kZ3ThIk%
this.userService = userService; ,nm*q#R,0
} [q #\D
} C~iL3Cb
Dm<A
^u8
n6a`;0f[R
kW&TJP+5*
[IhYh<i
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Ek]'km!
)+ 2hl
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Jg|XH
L)
d-dEQKI?;
么只需要: N<injx
java代码: R*2E/8Ia
\P`hq^;
>\3V a
<?xml version="1.0"?> &KRX[2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Npy:!
6 ~w@PRy
1.0//EN" "http://www.opensymphony.com/xwork/xwork- N//KPh
<GaS36ZW
1.0.dtd"> y_lU=(%Jd
r<^HmpUJ
<xwork> E=!\z%4
.OY`Z)SS%
<package name="user" extends="webwork- @6T/Tdz
g7W"
interceptors"> |8tilOqI
I&W=Q[m
<!-- The default interceptor stack name hx]?&zT@
N[
Og43Y
--> A2jUmK.&
<default-interceptor-ref q5)O%l !
fmDCP kj
name="myDefaultWebStack"/> PxDh7{
]3.;PWa:
<action name="listUser" x+@rg];m
N5b!.B x-w
class="com.adt.action.user.ListUser"> HCC#j9UN6
<param @r/nF5
oEZdd#*;
name="page.everyPage">10</param> %M|hA#04vZ
<result }Ud*TOo `
_>X+ZlpU:
name="success">/user/user_list.jsp</result> ( 0_2sfS
</action> YglmX"fLf
<B6H. P =
</package> dVT$ VQg
@QP z#-
</xwork> M:B=\&.O
338k?nHxv
n8ZZ#}Nhg
l)l^[2
_.Uh)-yR
%aVq+kC h
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 x-&@wMqkc
'kO!^6=4M
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。 lp%pbx43s
ZeaA%y67U
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Vb]=B~ ^`
={@6{-tl
;,:`1UI
+*/Zu`kzX
z/@slT
我写的一个用于分页的类,用了泛型了,hoho Od,qbU4O
fSvM(3Y<Qh
java代码: _5Ct]vy
R)s:rJQ=p
,S]7 'UP
package com.intokr.util; jLHkOk5{:
S k\K4
import java.util.List; Ls+2Zbh
Tqn@P
/** 5f K_Aq{
* 用于分页的类<br> nazZ*lC
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Gm^U;u}=f
* EaY?aAuS:
* @version 0.01 kzUIZ/+ZL,
* @author cheng ^'{Fh"5
*/ ]Wlco
public class Paginator<E> { p}pjfG
privateint count = 0; // 总记录数 eF-."1
privateint p = 1; // 页编号 !9VY|&fHe
privateint num = 20; // 每页的记录数 -3Z,EaG^
privateList<E> results = null; // 结果 O23k:=Av
q Y?j#fzi
/** O^duZ*b
* 结果总数 e)?
.r9pA;
*/ =|y9UlsD
publicint getCount(){ j[J-f@F \Y
return count; E,x+JeKV
} wc^tgE
h( u8&MHx
publicvoid setCount(int count){
B Qxs~
this.count = count; ag;pN*z
} tGE$z]1c@
9`X\6s
/** hT&Y#fh
* 本结果所在的页码,从1开始 >rmqBDKaQ
* ZdWm:(nkU
* @return Returns the pageNo. ~t~k2^)|"
*/ Q1I6$8:7
publicint getP(){ W/bQd)Jvk
return p; Ee%%d
} Q6!zZ))~
sfugY(m
/** z3m85F%dR
* if(p<=0) p=1 WUXx;9 >
* o&)8o5
* @param p k1Y ?
*/ }I6veagK
publicvoid setP(int p){
goOCu
if(p <= 0) dhf!o0'1M
p = 1; u5b|#&-mX
this.p = p; BLf>_bUk
} DGn;m\B
;~ $'2f~U
/** tOd&!HYL
* 每页记录数量 -4IE]'##
*/ +RM SA^
publicint getNum(){ i0kak`x0
return num; }t=!(GOb}
} }9# r0Vja
pis`$_kmwV
/** 1N#|
}ad
* if(num<1) num=1
}Gm>`cw-
*/ S8wLmd>
publicvoid setNum(int num){ IT7wT+
if(num < 1) J~zUp(>K
num = 1; */^q{PsN
this.num = num; ;dtA4:IRZ4
} %XoiVlT@:
{{D)YldtA
/** *-=(Q`3
* 获得总页数 mt+Oi70
*/ 7yH"l9Z
publicint getPageNum(){ }1c|gQ
return(count - 1) / num + 1; PI:4m%[
} e L^|v
)D5"ap]fX
/** $m{:C;UH
* 获得本页的开始编号,为 (p-1)*num+1 vzs)[AD
*/ 8f)?{AX0
publicint getStart(){ Fg5kX
return(p - 1) * num + 1; 0$)>D==
} *ebSq)
{JO
/** 7cT~oV !G_
* @return Returns the results. p{Yv3dNl
*/ FaQe_;
publicList<E> getResults(){ L~rBAIdD
return results; vrhT<+q
} JPc+rfF
$%CF8\0
public void setResults(List<E> results){ sV{,S>s
this.results = results; Sw8]EH6
} +mmSfuO&\
3G)#5Lf<
public String toString(){ 7uS~MW
StringBuilder buff = new StringBuilder 0w\zLU
7Oa#c<2]
(); Pg0x/X{t
buff.append("{"); mzaWST]
buff.append("count:").append(count); vv3*
j&I
buff.append(",p:").append(p); 0d"[l@UU0
buff.append(",nump:").append(num); 7$vYo
_
buff.append(",results:").append \FbvHr,
?qLFaFt/
(results); Yq0| J
buff.append("}"); *8yAG]z
return buff.toString(); jk; clwyz/
} +,TRfP
Fb
@uqd.Q
} ?wiCQ6*$
|+FubYf?$
~q@|l3?$