Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _Iy)p{y
.vmCKZ
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Zu#^a|PE*
vKoQ!7g
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 ?a+J4Zr3
[EPRBK`=
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 M&Q&be84
uAYDX<Ja9
。 s;<]gaonB_
Q%'4jn?H
分页支持类: F'<XB~&o
7zQGuGo(
java代码: l66 QgPA
4t*VI<=<[
w'i+WEU>l
package com.javaeye.common.util; BThrv$D}
#m7evb5eg*
import java.util.List; t:.X=/02
U>n.+/ss
publicclass PaginationSupport { p&XuNk
,UVd+rY}
publicfinalstaticint PAGESIZE = 30; Rwj
3o
@(/$;I,
privateint pageSize = PAGESIZE; Ei,dO;&
=*(_sW6;
privateList items; Xhyc2DKa_
6a]Qg99\
privateint totalCount; Nsy>qa7
,uO?f1
privateint[] indexes = newint[0]; Ey&A\
gvjy'Rm
privateint startIndex = 0; >0N$R|B&
L!5="s[}
public PaginationSupport(List items, int S2I{?y&K
jxw8jo06:
totalCount){ *W}nw$tnBX
setPageSize(PAGESIZE); JDpW7OrDc
setTotalCount(totalCount); F%ukT6xp
setItems(items); slA~k;K:_
setStartIndex(0); !9zs>T&9a\
} 0}_1ZU
sZa>+
public PaginationSupport(List items, int r_^]5C\
coXm*X>z
totalCount, int startIndex){ A8nf"mRD:
setPageSize(PAGESIZE); k~Y_%#_
setTotalCount(totalCount); /ubGa6N
setItems(items); 0ZAtBq.s
setStartIndex(startIndex); \o?
} 0oyZlv*
O,&p"K&Z
public PaginationSupport(List items, int %[?{H} y
Q`h@-6N
totalCount, int pageSize, int startIndex){ :$^sI"hO
setPageSize(pageSize); d$D3iv^hyx
setTotalCount(totalCount); yrMakT =
setItems(items); nzi)4"3O
setStartIndex(startIndex); :=`N2D
} =5p?4/4 J
<~5$<L4
publicList getItems(){ fJ-8$w\uL
return items; t2-bw6U
} xtS0D^
nza^<DlS
publicvoid setItems(List items){ SP|Dz,o
this.items = items; V+y:!t`
} }?d
l.=eq
1z8AK"8
publicint getPageSize(){ 0j-;4>p
return pageSize; 4mWT"T-8
} q'[yYPDX5x
K@=_&A!
publicvoid setPageSize(int pageSize){ -QydUr/(o
this.pageSize = pageSize; 5~omZ,qe
} J$Ba*`~!!
4[LzjC
publicint getTotalCount(){ L_YY,
return totalCount; 'q*/P&x5
} Dmk~t="Y
~gbq^
publicvoid setTotalCount(int totalCount){ pdR&2fp
if(totalCount > 0){ #kEa&Se
this.totalCount = totalCount; X?] 1/6rV
int count = totalCount / 8:UV; 5@
<7~+ehu
pageSize; 2fJ2o[v
if(totalCount % pageSize > 0) SJI+$L\'
count++; D)LqkfJ}z^
indexes = newint[count]; kKSn^qL*
for(int i = 0; i < count; i++){ $Xo_C_:B
indexes = pageSize * \CE8S+Z%
.SSj=q4?
i; FBK6{rLMc
} !TuMrA*
}else{ `Df)wNN1
this.totalCount = 0; ~%:23mIk
} DadlCEZv
} ZTSNM)f
\c$!C8z
publicint[] getIndexes(){ 8|p*T&Cn&
return indexes; a?9Ka!O4s
} >&N8Du*[
M&O .7B1}
publicvoid setIndexes(int[] indexes){ w6l8RNRe
this.indexes = indexes; -J*jW
N!
} (%EhkTb
Mi"dFx^Md
publicint getStartIndex(){ E MKv)5MH
return startIndex; du4Q^-repC
} [L@ vC>G
H23-%+*J
publicvoid setStartIndex(int startIndex){ -^LEGKN
if(totalCount <= 0) H<YS2Ed
this.startIndex = 0; O>`DR0
elseif(startIndex >= totalCount) 8CKI9
this.startIndex = indexes lGr(GHn
Doy7prKI8
[indexes.length - 1]; Obu>xK(
elseif(startIndex < 0) 0dgp<
this.startIndex = 0; m48m5>
else{ 5*pCb,z>q
this.startIndex = indexes J$D#)w!$j
QR($KW(
[startIndex / pageSize]; /A;!g5Y
} `!\`yI$!%w
} BI-xo}KI
@{!c [{x,T
publicint getNextIndex(){ 0X3kVm<
int nextIndex = getStartIndex() + [MKL>\U
m [FH>
pageSize; Cuq=>J
if(nextIndex >= totalCount) ?F9:rUyN
return getStartIndex(); r9uuVxBD
else !bG%@{W T
return nextIndex; />zE$)'M
} a:tCdnK/
(r?41?5K
publicint getPreviousIndex(){ LHb(T`.=
int previousIndex = getStartIndex() - ^H1B62_
8D U|j-I8
pageSize; EsU-Ckb_2:
if(previousIndex < 0) 0x\bDWZ_
return0; gUB%6v G\I
else wh@;$s"B
return previousIndex; Ul@yXtj
} Jiljf2h
+Q3i&"QB.
} /=}w%-;/;
L}1|R*b
c_li.]P
\ueo^p]_?
抽象业务类 pAo5c4y!4
java代码: c} GH|i
W"_")V=QBz
V3NQij(
/** #,1Kum
bG3
* Created on 2005-7-12 $ Aw"?&d"
*/ 2WRa@;Tj
package com.javaeye.common.business; Oozt&* F
YULI
y-W
import java.io.Serializable; CD'.bFO^+T
import java.util.List; *eAsA(;
Yp1;5Bbp
import org.hibernate.Criteria; e:E:"elr]
import org.hibernate.HibernateException; sF$$S/b
import org.hibernate.Session; 25RFi24>D
import org.hibernate.criterion.DetachedCriteria; 1o. O]>
import org.hibernate.criterion.Projections; oZkjg3
import YzqUOMAt"V
I65W^b4y
org.springframework.orm.hibernate3.HibernateCallback; gUs.D_*
import 0?KY9
T\VKNEBo
org.springframework.orm.hibernate3.support.HibernateDaoS xG JX~)
GRK+/1C
upport; #MbkU])
RG9YA&1ce
import com.javaeye.common.util.PaginationSupport; ykv,>nSXLL
k[0Gz
public abstract class AbstractManager extends |^^'GZ%a
_H9.AI
HibernateDaoSupport { \YE(E04w57
B 3Y,|*
privateboolean cacheQueries = false; ?32gug\i'}
iX]Vkx
privateString queryCacheRegion; A~_*vcz
"&s9;_9
publicvoid setCacheQueries(boolean nCZ&FNi{O~
5G"DgG*<
cacheQueries){ u:Fa1 !4JR
this.cacheQueries = cacheQueries; E)l0`83~^
} iYi3x_A`
wJs#rkW
publicvoid setQueryCacheRegion(String 7{%_6b"
kQ5mIJ9(
queryCacheRegion){ LD]a!eY
this.queryCacheRegion = slC
38
tONX<rA|]
queryCacheRegion; n.&z^&$w\)
} K}e%E&|>
&eL02:[
publicvoid save(finalObject entity){ $9!2c /
getHibernateTemplate().save(entity); +ML4.$lc^
} }w{6Ua
[&e|:1
publicvoid persist(finalObject entity){ >?/Pl"{b
getHibernateTemplate().save(entity); cn62:p]5
} m5c?A+@fZ
%~eIx=s
publicvoid update(finalObject entity){ TUw+A6u:p
getHibernateTemplate().update(entity); {O ]^8#v^
} AI{Tw>hZ
;m<22@,E&
publicvoid delete(finalObject entity){ d<{>&
getHibernateTemplate().delete(entity); {t<E*5N]a
} ~:`5Y"Av:
EDQKb TaPt
publicObject load(finalClass entity, !6Sr*a*5
;L1Q"Hxh
finalSerializable id){ 37OU
return getHibernateTemplate().load }H^h~E
dwd5P7
(entity, id); <$6r1y*G
} {kCCpU
a_jw4"Sb
publicObject get(finalClass entity, |\/`YRg>
gEghDO_G
finalSerializable id){ 00jW s@K
return getHibernateTemplate().get Q&j-a;L
z TYHwx
(entity, id); +ZFw3KEkz
} #m
x4pf{
}q<p;4<\F
publicList findAll(finalClass entity){ muh[wo
return getHibernateTemplate().find("from =<yMB d\
~s3X&!#
" + entity.getName()); -|K^!G
}
Iw)}YZmn
=geopktpf
publicList findByNamedQuery(finalString H(L.k;B
?4k/V6n@y
namedQuery){ .|\}]O`
return getHibernateTemplate cQg:yoF
4= 7#=F1
().findByNamedQuery(namedQuery); _C`&(?}
} z$64Ep#
+D7>$&BD
publicList findByNamedQuery(finalString query, x*H,eY3
* {avx
finalObject parameter){ 8
5 L<
return getHibernateTemplate GkwdBy+
/!7
().findByNamedQuery(query, parameter); bsuGZ
} z):LF<
e}f#dR+(
publicList findByNamedQuery(finalString query, voX4A
pl
O0Z!*Hy
finalObject[] parameters){ ^/6LVB *
return getHibernateTemplate 1zNh&
"
vIq>QXb;d
().findByNamedQuery(query, parameters); '80mhrEutG
} wh Hp}r
%#go9H(K
publicList find(finalString query){ _HMQx_e0YM
return getHibernateTemplate().find k)j6rU
={'3j
(query); -!@]z2uU
} p!oO}gE
0P_=Oy"l-
publicList find(finalString query, finalObject /penB[1i
NL^;C3u
parameter){ kAV4V;ydh
return getHibernateTemplate().find 53X i)
u~O9"-m !V
(query, parameter); ;AH8/M B9
} .-Z=Aa>
ZVX1@p
public PaginationSupport findPageByCriteria B4
k5IS
*A&A V||q
(final DetachedCriteria detachedCriteria){ PF+ F^;C
return findPageByCriteria wI5(`_l{G
ahh&h1q7|
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3<XP/c";
} wZUZ"Y}9
$.Ia;YBf
public PaginationSupport findPageByCriteria QLm#7ms*y
O*SJx.
(final DetachedCriteria detachedCriteria, finalint FOyANN'
wC>}9OM
startIndex){ 7v']wA r]
return findPageByCriteria Wq2Bo*[*
~|Nj+A
(detachedCriteria, PaginationSupport.PAGESIZE, 2%?Kc]JY9
$x~U&a
startIndex); gB_gjn\
} w,T-vf
g+j\wvx0
public PaginationSupport findPageByCriteria
S4S}go*G[
8l>7=~Egp
(final DetachedCriteria detachedCriteria, finalint q _INGCJ
~0@uR
pageSize, $x/VO\Z{-
finalint startIndex){ A3Xfu$[u
return(PaginationSupport) <B
Vx%
:R'={0Jg
getHibernateTemplate().execute(new HibernateCallback(){ u<U8LR=)V5
publicObject doInHibernate Mdw"^x$7
~hxW3e
(Session session)throws HibernateException { YB+My~fw{l
Criteria criteria = 2!)|B
;y
g#iRkz%l)&
detachedCriteria.getExecutableCriteria(session); +Pc2`,pw|
int totalCount = ,. HS )<B
|jI|},I
((Integer) criteria.setProjection(Projections.rowCount gJH^f3
79z/(T+
()).uniqueResult()).intValue(); t`-
[
criteria.setProjection 'WNq/z"X
tjLG$M1z`
(null); !ra,HkU'
List items = J[{ R:l\
*DgRF/S
criteria.setFirstResult(startIndex).setMaxResults A I v
OwN~-).%-
(pageSize).list(); P6 7*-Ki
PaginationSupport ps = (j(hr'f
wii.0~p
new PaginationSupport(items, totalCount, pageSize, YJ!jdE}
Yc:>Yzj(z
startIndex); 7 \AoMk}
return ps; m;J'y2h =$
} yRivf.wH
}, true); ok1w4#%,
} _G$21=
J1R5_b
public List findAllByCriteria(final 2"QcjFW%
*`40B6dEr
DetachedCriteria detachedCriteria){ nGM;|6x"8|
return(List) getHibernateTemplate ^v&"{2
q%/\
().execute(new HibernateCallback(){ 8]i7wq#=
publicObject doInHibernate v*kX?J#]5
g;7W%v5wqk
(Session session)throws HibernateException { U
UhlKV|5
Criteria criteria = D/ tCB-+
G|I}x/X"Q7
detachedCriteria.getExecutableCriteria(session); BZa`:ah~x
return criteria.list(); pwvmb\
} ,z01*Yx
}, true); x21XzGLY|}
} ~J0r%P
*^iSP(dg
public int getCountByCriteria(final Xb~i?T;f
OYfRtfE
DetachedCriteria detachedCriteria){ ,*sKr)9)
Integer count = (Integer) b"2_EnE}1
Jim5Ul
getHibernateTemplate().execute(new HibernateCallback(){ \('WS[$2
publicObject doInHibernate ?^ R"a##
/&E]qc*-p
(Session session)throws HibernateException { Uuktq)NU
Criteria criteria = I%jlM0ZUI"
ub2B!6f a
detachedCriteria.getExecutableCriteria(session); JkEITuTth
return sD9OV6^{?K
g^{a;=
criteria.setProjection(Projections.rowCount )m
Ii.
,va2:V
()).uniqueResult(); ~uG/F?= Q:
} q#F+^)DD [
}, true); hT%
>)71
return count.intValue(); ~wu\j][2
} QJ%N80
} _U
o3_us
[M#(su0fv
)=!|^M
g)}q3-<AK>
P\h1%a/D
oz%{D@CF
用户在web层构造查询条件detachedCriteria,和可选的 vCn~-Q
%Q=rm!Syv
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ]l"9B'XR
CropHB/t
PaginationSupport的实例ps。 ^[6#Kw&E
(ylZ[M&B:
ps.getItems()得到已分页好的结果集 iM$iZ;Tp
ps.getIndexes()得到分页索引的数组 y"iK)SH
ps.getTotalCount()得到总结果数 94?/Rhs5
ps.getStartIndex()当前分页索引 h(i_'P?
ps.getNextIndex()下一页索引 -,ojZFyRi
ps.getPreviousIndex()上一页索引 {rzQ[_)EC
x=N0H
TpYdIt9#>
6%V#_]
6A4{6B
[xXV5 JU
A~;.9{6J[t
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 )>N=B 2P
lI3d
_cU
,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 p::`1
@vO~'Xxq!
一下代码重构了。
QrLXAK\5
pS8`OBenA
我把原本我的做法也提供出来供大家讨论吧: ;,Os3
"2:#bXM-
首先,为了实现分页查询,我封装了一个Page类: q8&^E.K
java代码: 1i#U&
M8VsU*aU
/px`FuJI(
/*Created on 2005-4-14*/ wsj5;(f+
package org.flyware.util.page; Yez
aW#^@||B
/** ]sqp^tQ`e
* @author Joa LAGg(:3f3
* b~?3HY:t~K
*/ ,w,)n^
publicclass Page { +$R%Vbd
_@Y17L.
/** imply if the page has previous page */ &D` $YUl@
privateboolean hasPrePage; ]_hXg*?
s5ILl wr
/** imply if the page has next page */ F~3 &@TWi
privateboolean hasNextPage; d3 p;[;`
n*hRlL
/** the number of every page */ MNX-D0`g
privateint everyPage; _:Ov-HIR
0Hr)h{!F"
/** the total page number */ $oIGlKc:L
privateint totalPage; iJk/fvi
!6_tdZ
/** the number of current page */ *jl_,0g]
privateint currentPage; T_qh_L3
u73/#!(1=H
/** the begin index of the records by the current V6b)
Yt;@@xe&
query */ Ifj%" RI
privateint beginIndex; !<^`Sx/+
|RI77b:pX
7T?7KS
/** The default constructor */ P#2;1ki>
public Page(){ X6oY-4O
=@k3*#\
} 6K5KkEp
_LLE~nUK"/
/** construct the page by everyPage yF1^/y!@
* @param everyPage e0<L^|S
* */ leEzfbb{'.
public Page(int everyPage){ tUs{/Je
this.everyPage = everyPage; 0.!Q4bhD
} 5O"wPsl
uzL IllVX*
/** The whole constructor */ W97
&[([
public Page(boolean hasPrePage, boolean hasNextPage, r<.*:]L
=_d-MJy~6
}q~xr3#
int everyPage, int totalPage, MP`WU} 2
int currentPage, int beginIndex){ _ 3>|1RB
this.hasPrePage = hasPrePage; dUpOg{I.x
this.hasNextPage = hasNextPage; B'D4]EB
this.everyPage = everyPage; \8SHX
this.totalPage = totalPage; 4?e7s.9N
this.currentPage = currentPage; d?(eL(W
this.beginIndex = beginIndex; l7GLN1#m
} ^i~'aq
(9D,Ukw
/** 3yIC@>&y(8
* @return 2n5{H fpY
* Returns the beginIndex. :6Sb3w5h
*/ a<{+
JU5
publicint getBeginIndex(){ kx3]A"]>'
return beginIndex; ctL,Mqr\Z
} ;AgXl%Q
\J^|H@;(@
/** y8\4TjS1
* @param beginIndex V~qlg1h
* The beginIndex to set. cx(b5Z
*/ 0)3*E)g{
publicvoid setBeginIndex(int beginIndex){ -\=kd {*B
this.beginIndex = beginIndex; mH09*
Z
} $kk!NAW
W=
\gPCo
/** y'pX/5R0
* @return #oD*H:%*
* Returns the currentPage. 8fs::}0
*/ %+Khj@aX
publicint getCurrentPage(){ 4U1"F 7'
return currentPage; `F1 ( v
} ;u: }rA)
SwPc<Z?P
/** D*#r
V
P
* @param currentPage '5"`H>[
* The currentPage to set. })}-K7v1+
*/ WD5ulm?91|
publicvoid setCurrentPage(int currentPage){ T Jp0^&Q
this.currentPage = currentPage; :j0r~*z-
} nxh9'"th
~WG#Zci-
/** p![CH
* @return Y+I`XeY
* Returns the everyPage. +Udlt)H
*/ L`{EXn[
publicint getEveryPage(){ &O.S ;b*+
return everyPage; y|@=j~}Zq
} k"2xyzt*
s*DDO67\W
/** Zcn,_b7
* @param everyPage oXkxd3
* The everyPage to set. *n%J#[e(
*/ P9D'L{yS/x
publicvoid setEveryPage(int everyPage){ Wc)f:]7
this.everyPage = everyPage; tJ9i{TS
} r-a/vx#
slKL(-D{
/** [bvI T]Z
* @return =j1rw
* Returns the hasNextPage. i3} ^j?jA2
*/ ]gQ4qu5
publicboolean getHasNextPage(){ 5:H9B
return hasNextPage; *xOrt)D=
} Y-WYQ{
Q[k7taoy
/** ~IKPi==@,
* @param hasNextPage ,&IBj6%Y
* The hasNextPage to set. nP >*0Fq
*/ >K9uwUi|b]
publicvoid setHasNextPage(boolean hasNextPage){ A@0%7xm
this.hasNextPage = hasNextPage; ^KJIT3J(#
} Gm.n@U p
ryq95<lF
/** w(9.{zF|vQ
* @return eOQUy+
* Returns the hasPrePage. kEE8cW3
*/ \}e1\MiZ
publicboolean getHasPrePage(){ dEp?jJP$;
return hasPrePage; }X3SjNd q
} $Q|t^(
QpPJ99B|
/** p|M 8ww
* @param hasPrePage b!ZXQn3X<
* The hasPrePage to set. aMFUJrXo
*/ ~sQN\]5VW
publicvoid setHasPrePage(boolean hasPrePage){ ;?i(WV}ee
this.hasPrePage = hasPrePage; YQ_3[[xT
} cFoDR
mq?5|`
/** RYaf{i`
* @return Returns the totalPage. 8 JUUK(&Z
* V(Ps6jR"BS
*/ :sBg+MS
publicint getTotalPage(){ & ;+u.X
return totalPage; hb"t8_--c
} gC#PqK~
'Z+~G
/** z2&SZ.mk
* @param totalPage +?~'K&@
* The totalPage to set. u4=j!Zb8}
*/ por[p\ M.
publicvoid setTotalPage(int totalPage){ ]iuM2]
this.totalPage = totalPage; xaWm wsym
} M ,8r{[2
D!~-53f@
} x(z[S$6Y\
~3.1.
'A
` =!&9o
z$E+xZ
pI
|;
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 [BHf>
Mrp'wF
D
个PageUtil,负责对Page对象进行构造: 8Z!+1b
java代码: 9
I> 3p4]
@#}9?>UV
s!09Pxc
/*Created on 2005-4-14*/ pAYH"Q6~)I
package org.flyware.util.page; dvk?A$
oQ 5g0(J~
import org.apache.commons.logging.Log; iZQwo3"8r
import org.apache.commons.logging.LogFactory; ](vshgp2
n< [np;\
/** %,GY&hTw
* @author Joa SU9#Y|I
* 5DfAL;o!
*/ <$n%h/2%
publicclass PageUtil { WJZW5
Xt
sD.bBz
privatestaticfinal Log logger = LogFactory.getLog I -i)D
})Rmu."\
(PageUtil.class); I;L$Nf{v
bh?Vufd%)
/** uYS?# g
* Use the origin page to create a new page \@Gyl_6^
* @param page 0i9y-32-
* @param totalRecords jNV2o
* @return 'z2}qJJ)
*/ 0yXUVKq3
publicstatic Page createPage(Page page, int Zbxd,|<|
7Rj!vj/
totalRecords){ ,*r"cmz
return createPage(page.getEveryPage(), tq?lF$mM:
BSG_),AH
page.getCurrentPage(), totalRecords); FZnkQ
} O: sjf?z
KGkzE
/** kqSCKY1
* the basic page utils not including exception {!xPq%
&~U8S^os
handler *~M=2Fj;i
* @param everyPage <FMW%4
* @param currentPage &TSt/b/+W
* @param totalRecords *8U+2zgfC
* @return page b/ 'fC%o,
*/ +M
(\R?@gr
publicstatic Page createPage(int everyPage, int Fm{Ri=X<:
<dDGV>n4;
currentPage, int totalRecords){ cg<10KT
everyPage = getEveryPage(everyPage); o)cd!,h
currentPage = getCurrentPage(currentPage); ji`N1e,l
int beginIndex = getBeginIndex(everyPage, g||{Qmr=1
SMk{159q&
currentPage); U}6'_ PRQ
int totalPage = getTotalPage(everyPage, /9|1eSUa
)dG7$,g
totalRecords); '+Dn~8Y+9
boolean hasNextPage = hasNextPage(currentPage, FJv=5L
&7T0nB/)
totalPage); $.cNY+ k
boolean hasPrePage = hasPrePage(currentPage); t</rvAH E
`Qv7aY
returnnew Page(hasPrePage, hasNextPage, O qY8\>f-
everyPage, totalPage, oKz|hks[6
currentPage, Uq~{=hMX
|h*H;@$
beginIndex); 57)S"
} s7SW4ff1
4kNf4l9Y
privatestaticint getEveryPage(int everyPage){ BkJV{>?_+
return everyPage == 0 ? 10 : everyPage; HLAWx/c,j"
} CY0|.x
$B*E k>EK
privatestaticint getCurrentPage(int currentPage){ Dz]&|5'N
return currentPage == 0 ? 1 : currentPage; "}Ch2K
} A(W%G|+
<dD}4c+/t
privatestaticint getBeginIndex(int everyPage, int ]o_Z3xXUa
;)5d
wq
currentPage){ hv}rA,Yd
return(currentPage - 1) * everyPage; #wNksh/J^
} n%3rv?m7
2JYyvJ>
privatestaticint getTotalPage(int everyPage, int /Bid:@R
. 3=WE@M
totalRecords){ f3|ttUX
int totalPage = 0; L"1UUOKy
m7^aa@^m
if(totalRecords % everyPage == 0) gf2l19aP
totalPage = totalRecords / everyPage; @YMef`T:
else G7pj.rQ
totalPage = totalRecords / everyPage + 1 ; 8}\VlH]
4!d&Zc>C4
return totalPage; Q{UR3U'Q
} Zb8Ty~.\P
F5wCl2I
privatestaticboolean hasPrePage(int currentPage){ #c'yAa
return currentPage == 1 ? false : true; F5gL-\6
} ?7@B$OlU
j =r`[Bm
privatestaticboolean hasNextPage(int currentPage, c#$B;?
05LVfgJ'q
int totalPage){ Cv>|>Ob#
return currentPage == totalPage || totalPage == XN5EZ#
8*H-</ =
0 ? false : true; vmvk
} m7zen530
=2\k
Jv3
nY'0*:'u
} 1<fS&)^W
Tw)nFr8oF]
`Ff3H$_*
KIC5U50J
d `>M-:dF
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。 UQaLhKv:
36*"oD=@
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 8t!(!<iF0
#gMMhB=
做法如下: '~VKH}b
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %UI.E=`n
Lz2wOB1Zc+
的信息,和一个结果集List: *j?tcxq
java代码: a57Y9.H`o
xM8}Xo
';hU&D;s
/*Created on 2005-6-13*/ lt|\$Iy(
package com.adt.bo; |o6
h:g
XpdDIKMmE
import java.util.List; #25Z,UU
-/ ;y*mP
import org.flyware.util.page.Page; zu5'Ex`gQa
h
+.8Rl
/** ^&zwO7cS
* @author Joa ,G!M?@Q
*/ 6b~Zv$5^Y-
publicclass Result { ]{{A/ j\
N#Y%+1
private Page page; h=.|!u
FAfk;<#'n+
private List content; ^ ~:f02[D
gD3s,<>o
/** Gi~p-OS,
* The default constructor S(.AE@U
*/ iE=Yh
public Result(){ =<e|<EwSZ
super(); i6?,2\K
} %%`Nq&'
#:s*)(Qn
/** [4"1TyW
* The constructor using fields [mn@/qf
* l~;H~h!h/
* @param page ];Z)=y,vM
* @param content <gF=$u|}3[
*/ _T&?H
public Result(Page page, List content){ J0*hJ-/u
this.page = page; R
5-q{
this.content = content; <k<K"{
} KtchKpv
=dx!R ,Bw
/** (MY#;v\AYE
* @return Returns the content. n1m[7s.[&
*/ F B9PIsFS
publicList getContent(){ ns[v.YDL
return content; {a\O7$A\F
} 5ppOG_
'MRvH
lCM
/** $}_N379&
* @return Returns the page. HS XS%v/Y
*/ f]`#BE)V
public Page getPage(){ n0F.Um
return page; FRd!UqMXY
} PElC0qCn[
<cNXe4(
/** WSi`)@.XO
* @param content 'bJ!~ML&
* The content to set. _*7h1[,{f
*/ rl4B(NZi}
public void setContent(List content){ reR ><p
this.content = content; C,~wmS )@
} fft FNHP
JQ=i{ 9iJ
/** _x&;Fa%
* @param page gD10C,{
* The page to set. {a^A-Xh[u
*/ %KHO}gad1
publicvoid setPage(Page page){ 8@]*X,umc
this.page = page; W^npzgDCo
} n|2`y?
} Z>gxECi
`bT!_ Ru
'kb5pl~U
mbB,j~;^6H
g\S@@0T{0
2. 编写业务逻辑接口,并实现它(UserManager, (DJLq
:Rv?>I j
UserManagerImpl) r8g4NsRVtv
java代码: ;iR( Ir
tvXoF;Yq
I$/*Pt];
/*Created on 2005-7-15*/ ^]l^q'?>:
package com.adt.service; PPk\W7G
<~;; iM6
import net.sf.hibernate.HibernateException; :f%FM&b
DX GClH
import org.flyware.util.page.Page; VN[C%C
59mNb:<
import com.adt.bo.Result; K~ ,|~
ZycV?ob8}
/** s3qWTdM
* @author Joa nfpkWyI u{
*/ `q|&;wP.
publicinterface UserManager { mAMi-9
N`XJA-DE
public Result listUser(Page page)throws 56gpAc
U"$Q$ OFs
HibernateException; Ck;O59A"&-
7?Q@Hj(:NT
} o#3?")>|
y_EkW
f
uw!
JwCv(1$GM
M2HO!btf
java代码: ALvj)I`Al
bj23S&
\Zc$X^}vN
/*Created on 2005-7-15*/ Q|QVm,m
package com.adt.service.impl; ?#;
oqH<
^2f'I iE
import java.util.List; 7jvy]5y8&~
8 2qf7`
import net.sf.hibernate.HibernateException; HDQhXw!!hc
T'\B17
:*
import org.flyware.util.page.Page; !OWPwBm;
import org.flyware.util.page.PageUtil; 'F%4[3a$\n
Z|;<:RKWY
import com.adt.bo.Result; _svEPHU
import com.adt.dao.UserDAO; !Ic;;<
import com.adt.exception.ObjectNotFoundException; 4;"^1 $
import com.adt.service.UserManager; r_C|gfIP
0\v98g<[+
/** 3sG7G:4
* @author Joa
aEUC
*/ Fe
3*pUt
publicclass UserManagerImpl implements UserManager { }L
Q9db1
/2}o:vLj
private UserDAO userDAO; Q#C;4)e
_y#omEx
/** 5`qt82Qm
* @param userDAO The userDAO to set. [Du@go1C
*/ Y[%1?CREP
publicvoid setUserDAO(UserDAO userDAO){ HScj
this.userDAO = userDAO; *Q2;bmIc
} C!Cg.^;
9~+A<X]Hd
/* (non-Javadoc) eduaG,+k7p
* @see com.adt.service.UserManager#listUser \#4??@+Xf
z_%G{H+:l
(org.flyware.util.page.Page) we'<Y
*/ Z(Da?6#1
public Result listUser(Page page)throws +pYrA qmO-
F) w.q
HibernateException, ObjectNotFoundException { <p@c%e,_
int totalRecords = userDAO.getUserCount(); yXU-@~
if(totalRecords == 0) y,qP$5xiq
throw new ObjectNotFoundException fR_
jYP1
_&S?uz m
("userNotExist"); ;>^oe:@
page = PageUtil.createPage(page, totalRecords); iku8T*&uc
List users = userDAO.getUserByPage(page); B$~oZ'4v
returnnew Result(page, users); whb|N2
} DLMG<4Cd~
{FzL@!||
} %bI(
|8I #`
(Wkli:Lq
Zgp]s+%E
Y"
9 o
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rkhQoYZ[
dz/'
m7
询,接下来编写UserDAO的代码: @|Z:7n6S
3. UserDAO 和 UserDAOImpl: :xw2\:5~0
java代码: Ov3W;jD
9k\`3SE
=! v.VF\;
/*Created on 2005-7-15*/ ;t47cUm6j
package com.adt.dao; jvx9b([<sG
J6x\_]1:*
import java.util.List; 216+ tX5Z
M=[ /v/M=
import org.flyware.util.page.Page; 4 -)'a} O
T1zft#1~
import net.sf.hibernate.HibernateException; ,4y'(DA
N;,?k.vU
/** 97:1L4w.(
* @author Joa * d6[kY
*/ wUzQ`h2
publicinterface UserDAO extends BaseDAO { "%~\kJ(G
v +-f
pl&
publicList getUserByName(String name)throws U$a Eby.
SsA;T5:6
HibernateException; G yZYP\'S+
x_1JQDE
publicint getUserCount()throws HibernateException; }*Qd]\fy
tq=1C=h
publicList getUserByPage(Page page)throws "sLdkd}dj
<4jQbY;
HibernateException; y7SOz'd
:0o
$qz2
} Z4FyuWc3
b ABx'E
{9TWPB/>
"cjZ6^Hum
Mr'}IX5
java代码: M ,V+bt
HE&,?vioy
#QJ
mAA
/*Created on 2005-7-15*/ N/)mw/?i
package com.adt.dao.impl; pTq,"}J!+
U
-~%-gFC
import java.util.List; GypZ!)1
8xhXS1
import org.flyware.util.page.Page; GZT}aMMSJ
}C>Q
import net.sf.hibernate.HibernateException; 1"46OCu{
import net.sf.hibernate.Query; 9dA(f~
.lu:S;JSnS
import com.adt.dao.UserDAO; Rde_I`Ru
>4TJH
lB}8
/** FzmCS@yA
* @author Joa k*|dX.C:
*/ 2rHw5Wn]~
public class UserDAOImpl extends BaseDAOHibernateImpl Wu)ATs}
Sp)KtMV
implements UserDAO { SCeZt [
#oMbE<//"
/* (non-Javadoc) /R#-mY
* @see com.adt.dao.UserDAO#getUserByName }yqRz6=YB
J#*Uf>5NY
(java.lang.String) lEi,duS)
*/ oTtmn,
T
publicList getUserByName(String name)throws vl$! To9R"
Wm:3_C +j
HibernateException { Pb?H cg
String querySentence = "FROM user in class mm$D1=h{|
>`*iM
com.adt.po.User WHERE user.name=:name"; ^vm[`M
Query query = getSession().createQuery cJA0$)JP&
x( w <U1
(querySentence); O%9Cq}*
query.setParameter("name", name); 'R*gSqx~
return query.list(); /Nq!^=
} T(+F6d=1
322W"qduTZ
/* (non-Javadoc) yb/<
7
* @see com.adt.dao.UserDAO#getUserCount() x6HebIR+
*/ nzy =0Ox[
publicint getUserCount()throws HibernateException { uZZ[`PA(
int count = 0; uuj"Er31
String querySentence = "SELECT count(*) FROM 3DK^S2\zBm
o!mfd}nG
user in class com.adt.po.User"; d;S:<]l'
Query query = getSession().createQuery ->wY|7
;]fpdu{
(querySentence); hgj#VY$B
count = ((Integer)query.iterate().next j>&n5?
[2w3c4K
()).intValue(); y- k?_$M
return count; 7^sU/3z
} WAY<X:|We
&ukNzV}VW
/* (non-Javadoc) GQqw(2Ub}
* @see com.adt.dao.UserDAO#getUserByPage !N$4.slr<p
=D5@PHpv(
(org.flyware.util.page.Page) p@i U}SUaE
*/ qNHS 1
publicList getUserByPage(Page page)throws w GZ(bKyO
=\4w" /Y
HibernateException { 7 g ]]>
String querySentence = "FROM user in class ulfpop*2
.u7d
com.adt.po.User"; S
!c/"~X+
Query query = getSession().createQuery d!8q+FI
]+0-$t7Y
(querySentence); m?<8 ':
query.setFirstResult(page.getBeginIndex()) R
$'}Z
.setMaxResults(page.getEveryPage()); 3FPy"[[
return query.list(); &Wd,l$P<O
} 2?t(%uf]
e::5|6x
} hPr
#!#V!^ o
d\;M F
dMGu9k~u
N["c*=x
至此,一个完整的分页程序完成。前台的只需要调用 ZfT%EPoZ:
-Qnnzp$]
userManager.listUser(page)即可得到一个Page对象和结果集对象 nWFp$tJ/R
mMN oR]
的综合体,而传入的参数page对象则可以由前台传入,如果用 lNsPwyCoj
EfDo%H^!j
webwork,甚至可以直接在配置文件中指定。 ?;)(O2p
_Fl]zs<
下面给出一个webwork调用示例: pE `Q4:<A
java代码: 6$PfX.Fh
OD\x1,E)I
CyG @
/*Created on 2005-6-17*/ w** .8]A"N
package com.adt.action.user; >qtB27jV
FGwz5@|E
import java.util.List; DP^{T/G
)\mklM9Z
import org.apache.commons.logging.Log; a]X6) 6
import org.apache.commons.logging.LogFactory; eBU\&