Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 7'NwJ,$6\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @EE."T9
9qS"uj
据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 uKgZ$-'
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 T~h5B(J;
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。 ;3_l@dP"
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分页支持类: 52upoU>}2
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java代码: s=?g \oR
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package com.javaeye.common.util; <b/~.$a'
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import java.util.List; Kx_h1{
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publicclass PaginationSupport { ;S xFp
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publicfinalstaticint PAGESIZE = 30; yV)la@c
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privateint pageSize = PAGESIZE; ?5kHa_^
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privateList items; pm{|?R
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privateint totalCount; ~
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privateint[] indexes = newint[0]; pLv$\MiZ
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privateint startIndex = 0; 9n}p;3{f
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public PaginationSupport(List items, int [pVamE
/c):}PJ^#7
totalCount){ 4Jx"A\5*G
setPageSize(PAGESIZE); PqM1aoyX
setTotalCount(totalCount); )}9rwZ
setItems(items); !%dN<%Ah
setStartIndex(0); |d6T/Uxo
} :_M;E"9R
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public PaginationSupport(List items, int a~8[<F omj
wgd /(8d
totalCount, int startIndex){ Nan[<
setPageSize(PAGESIZE); MQin"\
setTotalCount(totalCount); {nU=%w"\
setItems(items); {}:ToIp
setStartIndex(startIndex); $['Bv
} <T[E=#
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public PaginationSupport(List items, int NWxUn.Gy9
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totalCount, int pageSize, int startIndex){ |>z3E z
setPageSize(pageSize); G9JAcO1
setTotalCount(totalCount); (rg;IXAq%
setItems(items); KD^N)&k^Kp
setStartIndex(startIndex); ZoArQ(YFy
} h;3cd0
&HSq(te
publicList getItems(){ ~)(\6^&=|
return items; -\#0]F:-
} /r_~:3F
^U]UqX`
publicvoid setItems(List items){ SM@QUAXO
this.items = items; t|m=J`a{q;
} q{+_
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10H)^p%3+
publicint getPageSize(){ <oz!H[!
return pageSize; zRPeNdX
} vB+ '
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publicvoid setPageSize(int pageSize){ fw[y+Bi&
?
this.pageSize = pageSize; Qyy.IPTP
} =Fdg/X1
]5%/3P,/
publicint getTotalCount(){ }-
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return totalCount; In[Cr/&/Y
} E\C9|1)
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publicvoid setTotalCount(int totalCount){ 0>zbCubPH
if(totalCount > 0){ VsA'de!V4[
this.totalCount = totalCount; WVLHfkN
int count = totalCount / 1IVuSp`{FU
tY
<Z'xA?
pageSize; VcoOeAKL
if(totalCount % pageSize > 0) *_ ?dVhxf
count++; 0:b2(^]bg
indexes = newint[count]; *&f$K1p
for(int i = 0; i < count; i++){ `Qqk<o
indexes = pageSize * i E CrI3s
~/*MY
i; `UBYp p
} gJM`[x`T
}else{ Y/7 $1k
this.totalCount = 0; H@l}WihW
} !fj(tPq
} yBI'djL~>
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publicint[] getIndexes(){ 7k8 pZ
return indexes; JY6
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} XU"~h64]
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publicvoid setIndexes(int[] indexes){ R+CM`4CD
this.indexes = indexes; O|w J)
} KIWe@e
%dY<=x#b
publicint getStartIndex(){ xNbPsoK
return startIndex; yiO.z
} F8apH{&t
NQ6sGL
publicvoid setStartIndex(int startIndex){ NC38fiH_N
if(totalCount <= 0) 7.`fJf?
this.startIndex = 0; db6mfxi
elseif(startIndex >= totalCount) 1/"WD?a
this.startIndex = indexes rdJR 2
s-v
[indexes.length - 1]; &?(?vDFfZ
elseif(startIndex < 0) +>PX&F
this.startIndex = 0; 6:~v4W!k
else{ )P+7PhE{J
this.startIndex = indexes AA7C$;Z15~
pa#IJ
[startIndex / pageSize]; s;A@*Y;v
} )6aAB|
} uS^Ipxe\
ow]053:i
publicint getNextIndex(){ ZMq6/G*fD
int nextIndex = getStartIndex() + s)pbS}L
Sm5H_m!
pageSize; ' MxrQ;|S
if(nextIndex >= totalCount) vuYSVI2=H
return getStartIndex(); O6OP =K!t:
else F|!){=
return nextIndex; 1@-Ns
} <%"b9T`'
hq #?kN
publicint getPreviousIndex(){ \o^2y.q:>
int previousIndex = getStartIndex() - j*vYBGD
#Q
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pageSize; sQ\8>[]
if(previousIndex < 0) 9B9(8PVG
return0; 5^x1cUB]
else Z+=@<i''
return previousIndex; 5@BBoeG
} {lc\,F* $
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} <Sr
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@!1x7%]G
抽象业务类 pS7w' H
java代码: 1 |jt"Hz
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/** VF ys.=
* Created on 2005-7-12 ~5oPpTAe
*/ sjV!5Z
package com.javaeye.common.business; \vO,Ee~#W
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import java.io.Serializable; @8I4[TE
import java.util.List; ;N?]eM}yf
p|p l
import org.hibernate.Criteria; Ug<#en
import org.hibernate.HibernateException; H|HYo\@F#
import org.hibernate.Session; av|g}xnj
import org.hibernate.criterion.DetachedCriteria; ?snp8W-WB
import org.hibernate.criterion.Projections; 4v{o
import Sxh]R+Xb
Iepsz
org.springframework.orm.hibernate3.HibernateCallback; jJPGrkr
import 4.5|2\[
gK'1ZLdZ2
org.springframework.orm.hibernate3.support.HibernateDaoS OD!& .%
<d$x.in
upport; XcUwr
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import com.javaeye.common.util.PaginationSupport; 7x%R:^*4
LHo3
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public abstract class AbstractManager extends g0["^P1tV
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HibernateDaoSupport { B e0ND2oo
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privateboolean cacheQueries = false; 9j6QX~,
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privateString queryCacheRegion; |}di&y@-JI
MjC_ ( cs
publicvoid setCacheQueries(boolean F}/S:(6LF2
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cacheQueries){ /~$WUAh
this.cacheQueries = cacheQueries; abfW[J
} /Y2}a<3&0
U ^5Kz-5.
publicvoid setQueryCacheRegion(String _ =VqrK7T
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queryCacheRegion){ LoN< oj5
this.queryCacheRegion = T~##,qQ
;"~
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queryCacheRegion; x#xFh0CA
} :Ra,Eu
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publicvoid save(finalObject entity){ U"^kH|
getHibernateTemplate().save(entity); ,N]H dR
} \=ux atw
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publicvoid persist(finalObject entity){ =k^Y?.
getHibernateTemplate().save(entity); po2!
} %D%8^Zd_
a C\MJ9
publicvoid update(finalObject entity){ OX?\<),
getHibernateTemplate().update(entity); ij( B,Y
} TU,s*D&e
@v)p<r^M">
publicvoid delete(finalObject entity){ :2rZcoNb.
getHibernateTemplate().delete(entity); 8"8t-E#?
} oldA#sA$
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publicObject load(finalClass entity, &-Gqdnc
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finalSerializable id){ SBfT20z[
return getHibernateTemplate().load yDegcAn?
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(entity, id); AicBSqUke
} 3yU.& k
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publicObject get(finalClass entity, ~O
oidKT
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finalSerializable id){ (
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return getHibernateTemplate().get g4=pnK8
/-_h1.!
(entity, id); !h23cj+V
} IYS)7`{]
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publicList findAll(finalClass entity){ }J:U=HJ
return getHibernateTemplate().find("from :~tAUy":_*
#FCnA
" + entity.getName()); Ybs\ES'?A
} %7IugHH9y
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publicList findByNamedQuery(finalString t\k$};qJ
@ hiCI.?X
namedQuery){ /'l{E
return getHibernateTemplate `(ue63AZ
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().findByNamedQuery(namedQuery); "$+Jnc!!
} lm-dW'7&
P3x= 8_#
publicList findByNamedQuery(finalString query, '
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Q
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finalObject parameter){
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return getHibernateTemplate 59Xi3KY
s
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().findByNamedQuery(query, parameter); 8D3OOab
} mS$j?>m
=[cS0Sy
publicList findByNamedQuery(finalString query, [q)8N
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finalObject[] parameters){ v&Yi
return getHibernateTemplate Ai=se2
Pq;U&,
().findByNamedQuery(query, parameters); )wam8k5
} &:9cAIe]H
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publicList find(finalString query){ ;c-(ObSm
return getHibernateTemplate().find K6v6ynp/
Wuc S:8#|
(query); ZM!CaR
} 9kN}c<o
jnK WZ/R
publicList find(finalString query, finalObject ~:kZgUP_f
42{Ew8
parameter){ m ZtCL
return getHibernateTemplate().find #%iDT6
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(query, parameter); : UGZ+
} Bu<M\w?7Y
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public PaginationSupport findPageByCriteria [R(`W#W
591>rh)
(final DetachedCriteria detachedCriteria){ +7D|4
return findPageByCriteria 0=@?ob7
bv]`!g:
C
(detachedCriteria, PaginationSupport.PAGESIZE, 0); LSa,1{
} p4.wh|n
Se:.4<
public PaginationSupport findPageByCriteria 2,$8icM
Cc+t}"^
(final DetachedCriteria detachedCriteria, finalint l2zFKCGF(
@Owb?(6?
startIndex){ cs,N <|
return findPageByCriteria 8ndYV>{f
BZ94NOOdw
(detachedCriteria, PaginationSupport.PAGESIZE, fxgPhnaC>
4ni<E*
startIndex); #C~+JL
} c]x1HvPE
jSD#X3qp
public PaginationSupport findPageByCriteria aktU$Wbwl
[-65PC4aN
(final DetachedCriteria detachedCriteria, finalint iV5yJF{ZH
s:>VaGC
pageSize, ~("5yG
finalint startIndex){ YIn',]p:
return(PaginationSupport) ;(f)&Yom
X[*<NN
getHibernateTemplate().execute(new HibernateCallback(){ 0Is,*Srr
publicObject doInHibernate a]JYDq`,3
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(Session session)throws HibernateException { [pC$+NX
Criteria criteria = 3c#BKHNC
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detachedCriteria.getExecutableCriteria(session); ypbe!Y<i]
int totalCount = ''q@>
"9ZID-~]
((Integer) criteria.setProjection(Projections.rowCount N=4G=0 `ke
rXmn7;B}g
()).uniqueResult()).intValue(); *]ly0nP
criteria.setProjection y?[ v=j*U
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v
(null); F3N?Nk/
List items = 4,bv)Im+ `
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criteria.setFirstResult(startIndex).setMaxResults 1Ce@*XBU
yQ_B)b
(pageSize).list(); r54&XE]O
PaginationSupport ps = !POl;%\
Buf/@B7+\
new PaginationSupport(items, totalCount, pageSize, RY]#<9>M
`>7;!
startIndex); chcbd
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return ps; 14Xqn8uOW
} dT`D:)*:
}, true); 6CV*
Z\b
} |jQ:~2U|
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public List findAllByCriteria(final 3AHlSX
5m*iE*+
DetachedCriteria detachedCriteria){ WQ~;;.v#
return(List) getHibernateTemplate sd ,J3
:=}US}H$
().execute(new HibernateCallback(){ mPOGidxix
publicObject doInHibernate K{x\4
w,.+IV$Kk
(Session session)throws HibernateException { wF
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Criteria criteria = q-
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detachedCriteria.getExecutableCriteria(session); jlkmLcpf
return criteria.list(); G<At_YS
} yWg@v+
}, true); T_s_p
} 1{r3#MVL
whmdcVh.
public int getCountByCriteria(final S/}2; \Xm
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DetachedCriteria detachedCriteria){ GQ t8p[!
Integer count = (Integer) gD,1 06%
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getHibernateTemplate().execute(new HibernateCallback(){ >z/#_z@LV
publicObject doInHibernate r;B8i!gD
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(Session session)throws HibernateException { TlXI|3Ip
Criteria criteria = B:dB,3,`(
D2<fw#
detachedCriteria.getExecutableCriteria(session); ^"VJd[Hn
return W}3.E "K
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criteria.setProjection(Projections.rowCount "w^!/
#D<C )Q
()).uniqueResult(); bP8Sj16q
} O;z,qo X
}, true); ~rlB'8j(
return count.intValue(); CpA|4'#
} qS403+Su1=
} dq7x3v^"ZG
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@E^~$-J5j
~;QvWS
用户在web层构造查询条件detachedCriteria,和可选的 z8jk[5z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2>|dF~"
L;
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PaginationSupport的实例ps。 u}>#Eb
*v;!-F&8>
ps.getItems()得到已分页好的结果集 c]$i\i#
ps.getIndexes()得到分页索引的数组 qHsUP;7
ps.getTotalCount()得到总结果数 k>F'ypm
ps.getStartIndex()当前分页索引 ?5U2D%t
ps.getNextIndex()下一页索引 ~Fe${2
ps.getPreviousIndex()上一页索引 )i~cr2Hk
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d_AK`wR
yW+yg{Gg:
P7J>+cm
$"`- ^
hhSy0
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XUM!Qv
VcAue!MN
,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 uXI_M)
X'wE7=29M
一下代码重构了。 3t`P@nL0;
V_>\9m
我把原本我的做法也提供出来供大家讨论吧: ji1viv
YsG%6&zEq
首先,为了实现分页查询,我封装了一个Page类: sC27FVwo
java代码: -|kA)M[
TK5K_V*7
j;%-fvd;
/*Created on 2005-4-14*/ oE<`VY|
package org.flyware.util.page; Wc,_RN-
IN4=YrM^
/** s4G|_==
* @author Joa A:>01ZJ5S+
* cmBB[pk\
*/ ^:K3vC[h;c
publicclass Page { un shH <
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.>'
/** imply if the page has previous page */ ?;KKw*
privateboolean hasPrePage; lwHzj&/ ~
+)k b(
/** imply if the page has next page */ ^:6{2 2C{
privateboolean hasNextPage; ~oI1zNz/
6^%UU
o%
/** the number of every page */ LL] zT H0
privateint everyPage; -c(F 1l
0FGe=$vD
/** the total page number */ l-K9LTd
privateint totalPage; 1lq(PGX)
SLO%7%>p
/** the number of current page */ I{
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privateint currentPage; ^sa#8^,K
JQ}$Aqk
/** the begin index of the records by the current anIAM
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query */ W;_nK4$%'
privateint beginIndex; i\1TOP|h
>fe-d#!{
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/** The default constructor */ e:DkGy`-s
public Page(){ &L#UGp$,
.zS?9MP
} 8*8Zc/{
pF&(7u
/** construct the page by everyPage kspTp>~
* @param everyPage =jSb'Vu|
* */ A~Y^VEn
public Page(int everyPage){ W)9K`hM6
this.everyPage = everyPage; d_4T}%q
} Vm%1> '&
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/** The whole constructor */ ${+ @gJ+S
public Page(boolean hasPrePage, boolean hasNextPage, ElS 9?Q+
r~N"ere26
)A!>=2M`
int everyPage, int totalPage, (EK"V';
int currentPage, int beginIndex){ OC1I&",Ai|
this.hasPrePage = hasPrePage; }-ftyl7
this.hasNextPage = hasNextPage; KiI!frm1
this.everyPage = everyPage; O?U'!o=
this.totalPage = totalPage; XID<(HBA"!
this.currentPage = currentPage; |3F02
this.beginIndex = beginIndex; N5* u]j
} +u!0rLb
XS`M-{f`
/** s >e=?W
* @return Wi[ ~fI8^!
* Returns the beginIndex. "J+3w
*/ 20vXSYa~
publicint getBeginIndex(){ g) p,5BADm
return beginIndex; SxdE?uCUS
} (ohq0Y
lrnyk(M}Q.
/** *F
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* @param beginIndex KC(xb5x
Y
* The beginIndex to set. NLS%S q
*/ /3eKN
publicvoid setBeginIndex(int beginIndex){ 8CnRi
this.beginIndex = beginIndex; an4GSL
} s4 6}s{6
=:D aS`~V
/** -QOw8vm
* @return H,+I2tEs
* Returns the currentPage. H2Z1TIh
*/ ]?3un!o3o
publicint getCurrentPage(){ zXv3:uRp.
return currentPage; e_s&L,ze
} ?47@o1
Vnx,5E&
/** ?"zY"*>4
* @param currentPage RQ'exc2x0
* The currentPage to set. V6t,BJjS
*/ `kbSu}
publicvoid setCurrentPage(int currentPage){ 6T+FH;h
this.currentPage = currentPage; jov:]Bic
} }| J79s2M
{Z3dF)>
/** m>4ahue$
* @return q6_u@:3u
* Returns the everyPage. JL\w_v
*/ 5m?8yT}
publicint getEveryPage(){ xqC+0{]y
return everyPage; vw>2(K=e1
} p!sWYui
`!Ds6
/** CamE'
* @param everyPage 1QmH{jM
* The everyPage to set. T.Ryy"%F
*/ U>V&-kxtV
publicvoid setEveryPage(int everyPage){ >=UF-xk;
this.everyPage = everyPage; w=LP"bqlI
} ##@$|6
COTp
/** 8<.C3m
6h
* @return F;gx%[$GX
* Returns the hasNextPage. JNkwEZhHyg
*/ T/^Hz4uA7
publicboolean getHasNextPage(){ Jrg2/ee,*
return hasNextPage; )dY=0"4Z
} w"SoeU
YyTSyP4
/** e=4+$d
* @param hasNextPage _Qh
z3'I1
* The hasNextPage to set. ?T>'j mmV=
*/ z;A>9vQ_J
publicvoid setHasNextPage(boolean hasNextPage){ Vs%|pIV
this.hasNextPage = hasNextPage; h~(G$':^
} krsYog(^z
6U[4%(
/** 0PU8#2pR
* @return ([-|}
* Returns the hasPrePage. Z^]|o<.<I
*/ DyeQJ7p
publicboolean getHasPrePage(){ @J5Jpt*IE
return hasPrePage; ;]gP@ h/
} oqLfesV~
-RS7h
/** OCZ[D{i9@
* @param hasPrePage x9x E&
* The hasPrePage to set. 87:!C5e}
*/ 5B&;uY
publicvoid setHasPrePage(boolean hasPrePage){ C?i >.t
this.hasPrePage = hasPrePage; O!Oumw,$
} :um|nRwy9
&^}6
9
/** |1ST=O7.LH
* @return Returns the totalPage. G:pEE:W[
* U$
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*/ '@jXbN
publicint getTotalPage(){ +hE(Ra#
return totalPage; hSFn8mpXT
} ax{ ;:fW
Y$Q|J4z
/** y`$Q\}fS
* @param totalPage 6ezS {Q
* The totalPage to set. Tszp3,]f
*/ 34wkzu
publicvoid setTotalPage(int totalPage){ {dL?rQ>5L
this.totalPage = totalPage; 94 e):
jS
} ;x:rZV/
;=<-5;rI
} [@Q_(LQ-U
-
/(s#D
/v/C<]
H"C[&r
{}QB|IH`
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 -S$1Yn
>m#e:[N
个PageUtil,负责对Page对象进行构造: }';D]c
java代码: m=:4`_0Q
e|&6$A>4]
`5~ +,/Ys
/*Created on 2005-4-14*/ $2M#qkik-
package org.flyware.util.page; [74F6Qp
H(Q.a=&4!p
import org.apache.commons.logging.Log; 7<jZ`qdq_
import org.apache.commons.logging.LogFactory; Pfm_@'8
- !>}_AH
/** OvUI@,Ef
* @author Joa 'yV?*a
* b8%C*r7
*/ ^)?d6nI
publicclass PageUtil { #7ov#_2Jd
63.wL0~
privatestaticfinal Log logger = LogFactory.getLog c\ia6[3sX
Pl<;[cB
(PageUtil.class); u{FDdR9<
E[O<S B
I
/** n @?4b8"
* Use the origin page to create a new page C=s1R;"H
* @param page !A>z(eIsv`
* @param totalRecords f]G>(V=i
* @return !^v5-xO?rP
*/ \=0Vuz
publicstatic Page createPage(Page page, int <`jLY)sw
&f7fK|}
totalRecords){ V\})3i8
return createPage(page.getEveryPage(), 0]D{Va
bJYda)
page.getCurrentPage(), totalRecords); iSFuT7;%
} NCt~9xS.
we]>(|
/** T |"`8mG
* the basic page utils not including exception +g\;bLT
,ECAan/@
handler ()|3
* @param everyPage !L\'Mk/=A
* @param currentPage 2cnj@E:5l
* @param totalRecords |4SW[>WT:
* @return page Lx+`<<_dJ
*/ >BiRk%x
publicstatic Page createPage(int everyPage, int "n- pl
;) pl{_
currentPage, int totalRecords){ ~$aTM_4
everyPage = getEveryPage(everyPage); 3IyZunFT
currentPage = getCurrentPage(currentPage); Pz~q%J
int beginIndex = getBeginIndex(everyPage, J|j;g!fK
jXcNAl
currentPage); B?(4f2yE
int totalPage = getTotalPage(everyPage, 6v47 QW|'
O-GxUHwWr
totalRecords); %Y',|+Arx
boolean hasNextPage = hasNextPage(currentPage, \graMu}-
5H.Db
totalPage); %x2b0L\g
boolean hasPrePage = hasPrePage(currentPage); T\3 [F%?
sc xLB;
returnnew Page(hasPrePage, hasNextPage, @l>Xnqx)
everyPage, totalPage, 8R/
*6S=&
currentPage, TA)LPBG
k^*$^;z
beginIndex); )Qr6/c8}
} euZ(}+N&
(+MC<J/i
privatestaticint getEveryPage(int everyPage){ f)Y
return everyPage == 0 ? 10 : everyPage; iG-N
} BED@?:U# h
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privatestaticint getCurrentPage(int currentPage){ Bcaw~WD
return currentPage == 0 ? 1 : currentPage; bF6gBM@*
} S:Xs'0K_
JD&U}dJ
privatestaticint getBeginIndex(int everyPage, int #:
hVF/
)0|):g
currentPage){ pTET%)3
return(currentPage - 1) * everyPage; [$:@X V(
} qy9i9$8
9.-47|-9C
privatestaticint getTotalPage(int everyPage, int oc;VIK)g]c
H ja^edLj
totalRecords){ ay[ZsQC
int totalPage = 0; cHEz{'1m
!3x*k;0
if(totalRecords % everyPage == 0) ewQe/Fq
totalPage = totalRecords / everyPage; 3kw}CaZ6
else xMsGs
totalPage = totalRecords / everyPage + 1 ; )Pa*+ew7
=c]a
{|W?
return totalPage; H5p5S\g-)
} \\s?B K
Bm<^rhJ9
privatestaticboolean hasPrePage(int currentPage){ 9l l|JeNi
return currentPage == 1 ? false : true; ?Ccw4]YO,=
} bX&e_Pd
T/Q==Q{W:
privatestaticboolean hasNextPage(int currentPage, "G kI5!
NDW8~lkL
int totalPage){ Lupy:4AD
return currentPage == totalPage || totalPage == :B^mV{~
`vX4!@Tw
0 ? false : true; z"qv
} w`-$-4i
j!CU
qZ?{-Vw
} TK %<a/
%^U"Spv;
"uS7PplyO
oVEAlBm^v
<4$YO-:E
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。 X#7}c5^Y
PvuAg(?
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 H9:%6sds
oB}K[3uB:t
做法如下: wO!%
q[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 i :EO(`
d}VALjXHX!
的信息,和一个结果集List: 8.-S$^hj~6
java代码: BDp:9yau
ex=)H%_|
QA! #s\
/*Created on 2005-6-13*/ !c."
package com.adt.bo; H.9yT\f.
&|NZ8:*+#
import java.util.List; 3FuCW
_y"a2M
import org.flyware.util.page.Page; ik1XGFy?
?4MSgu
/** HoV{U zm
* @author Joa ysl8LK
*/ d["x=
[f
publicclass Result { 3Cd<p[%3#,
[xWEf#', !
private Page page; mDlCt_h
W0U`Kt&~a
private List content; /t$*W\PL@
niQ+EAD
/** pOX$4$VR<
* The default constructor eL_^: -
*/ Jxf}b}^T
public Result(){ "B~WcC
super(); _Ws#UL+Nq
} 4 *H(sq
tr5'dX4]
/** K:uQ#W.&
* The constructor using fields f%L:<4
* %kJh6J
* @param page nZ541o@t9
* @param content xl|ghjn
*/ $\0TD7p
public Result(Page page, List content){ L%k67>
this.page = page; 98h :X %
this.content = content; VZt;P%1;h
} \u{Jf'g
|$Qp0vOA}
/** ,RR;VKj
* @return Returns the content. Oe/73|
>U
*/ xSx&79Ez<*
publicList getContent(){ k"5`: qL
return content; \ hrBq^I
} I7A7X*
Kq8(d`g}
/** sC!1B6:
* @return Returns the page. >,kL p|gA
*/ >G<4Ro"
public Page getPage(){ f_~}X#._
return page; =obt"K%n
} PIgGXNo
3,%nkW
/** vwm|I7/w
* @param content y9=t;qH@|
* The content to set. 8?A@/
*/ o@Scz!"g
public void setContent(List content){ U.Pa7tn
this.content = content; YGfA qI
y
} gHp'3SnS
>c}:
/** q|R+x7x
* @param page YomwjKyuP
* The page to set. ~wa%fM
*/ f%vHx,
publicvoid setPage(Page page){ &qNP?>C!=
this.page = page; 0W;q!H[G
} j~Xj
} +[>yO _}
9)#gtDM%J
Ewa[Y=+tx
( P
v!nm
&"
2. 编写业务逻辑接口,并实现它(UserManager, !&'# a
k,a,h^{}j
UserManagerImpl) Lr K9F^c
java代码: yBr$ 0$
j@%K*Gb`
5wT',U"+
/*Created on 2005-7-15*/ 3s3a>
package com.adt.service; 58M'r{8_
I[tAT[ <
import net.sf.hibernate.HibernateException; qPp1:a"
Tbe_xs^
import org.flyware.util.page.Page; 7yo|ie@S
1-4
import com.adt.bo.Result; Q,OkO?uY
[6Uud iw
/** QWU5-p9e8
* @author Joa _K
4eD.
*/ '=KuJ0`nE9
publicinterface UserManager { Wpiv1GZ%c8
HR/k{"8W4Q
public Result listUser(Page page)throws L#@l(8.
, LCH2r
HibernateException; j4.Qvj >:4
$I?=.:<+
} gn-=##fT:i
I@8+k&nXS
[{hL F9yPx
6^7)GCq [
=YS!soO
java代码: ]hCWe0F
9nP*N`
daaga}]d
/*Created on 2005-7-15*/ >qSO,$
package com.adt.service.impl; z'5;f;
^4n2
-DvG
import java.util.List; .F{}~K]
{ Hktu|
import net.sf.hibernate.HibernateException; 7AZ5%o
6Y0/i,d*
import org.flyware.util.page.Page; ?7rmwy\
import org.flyware.util.page.PageUtil; {jj]K.&
~EM#Hc,
import com.adt.bo.Result; =Bcux8wA#6
import com.adt.dao.UserDAO; jldcvW
import com.adt.exception.ObjectNotFoundException; yb@X*PW/z
import com.adt.service.UserManager; SL?%/$2g=O
h$#4ebp
/** (.jO:#eE%
* @author Joa ?^e*UJNM
*/ e
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publicclass UserManagerImpl implements UserManager { ;XD>$t@
IqR[&T)lj
private UserDAO userDAO; RW|UQY#
<8F->k1"3
/** 2dp*>F0L
* @param userDAO The userDAO to set.
jgZX~D
*/ I1eb31<
publicvoid setUserDAO(UserDAO userDAO){ hr/xpQW
this.userDAO = userDAO; -y7l?N5F>
} ex;Yn{4
s+OvS9et_
/* (non-Javadoc) NKIk d
* @see com.adt.service.UserManager#listUser $G^H7|PzdC
\rw'QAi8r
(org.flyware.util.page.Page) cG~_EX$
*/ UcKWa>:Fi
public Result listUser(Page page)throws rm7*l<v6
'tq\<y
HibernateException, ObjectNotFoundException { H4K(SGx
int totalRecords = userDAO.getUserCount(); m \R@.jkZ
if(totalRecords == 0) (o6A?37i
throw new ObjectNotFoundException K4K3<Pg
Q@3ld6y
("userNotExist"); AOvH&9**
page = PageUtil.createPage(page, totalRecords); Z.cG`Km*
List users = userDAO.getUserByPage(page); g*"J10hyP
returnnew Result(page, users); y$;zTH_6j
} 3V8j>&
]8q%bsl+
} {4V:[*3
&L[8Mju6
qZyt>SAx
y7}~T!UyfF
2_ZHJ,r
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 V.E.~<7D\
>E2WZHzd2
询,接下来编写UserDAO的代码: Hsux>+Q
3. UserDAO 和 UserDAOImpl:
t`&s
java代码: .n^O)|Z
`gA5P %
`qYc#_ELv
/*Created on 2005-7-15*/ CM@"lV_
package com.adt.dao; SbQ{ >
ni 02N3R
import java.util.List; lzQ&)7`
f R{WS:Pv
import org.flyware.util.page.Page; #q^>qX
y
~k:>Xo[|O
import net.sf.hibernate.HibernateException; =-a?oH-
y+~Aw"J}
/** .,iw2:
* @author Joa l*V72!Mv
*/ CsQ}P)
publicinterface UserDAO extends BaseDAO { _#\5]D~""
z;@S_0M,Z
publicList getUserByName(String name)throws @?($j)9}
X~/9Vd g
HibernateException; YRT}fd>R&
sjVl/t`l
publicint getUserCount()throws HibernateException; 07HX5 Hd
=,}!Ns{k
publicList getUserByPage(Page page)throws zfT'!kb,(
qkyX*_}
HibernateException; EZNB`gO
8)Bn?6.
} T J"{nB
:[$i~V
*TMM:w|1
`:^)"#z)
H"Em|LX^
java代码: :fMM-?s]
W0C$*oe!_i
tI(t%~>^
/*Created on 2005-7-15*/ ^dp[Z,[1z
package com.adt.dao.impl; Ni;{\"Gt
nqw*oLFQ
import java.util.List; Zq6ebj
S3[oA&
import org.flyware.util.page.Page; L:]; [xa%
hF?\K^tF
import net.sf.hibernate.HibernateException; v(WL 3[y;
import net.sf.hibernate.Query; u>-uRz<)t
rBL_]\$7}
import com.adt.dao.UserDAO; )7 BNzj"~
i\c^h;wX
/** ]`+"o[
* @author Joa ?2
O-EiWjZ
*/ J5r
L7
public class UserDAOImpl extends BaseDAOHibernateImpl #on fac- 3
/)HEx&SQmZ
implements UserDAO { ^SES')x
vN[m5)aT
/* (non-Javadoc) @x\gk5
* @see com.adt.dao.UserDAO#getUserByName (4/`@;[
b9!J}hto,
(java.lang.String) #p^pvdvh3
*/ U*#E aL
publicList getUserByName(String name)throws A 5\"e^>
os0"haOI9h
HibernateException { 'G
By^hj?
String querySentence = "FROM user in class k1
txY
m+JGe5fR<
com.adt.po.User WHERE user.name=:name"; :y)&kJpleP
Query query = getSession().createQuery tLGwF3e$A
75cr!+
(querySentence); 4iB)oR
query.setParameter("name", name); 3_['[}
return query.list(); a>e
1jM[
} )fcpE,g'
[;\<
2 =H
/* (non-Javadoc) r4qV}-E
* @see com.adt.dao.UserDAO#getUserCount() ^*T{-U'
*/ ZJ'H y5?
publicint getUserCount()throws HibernateException { \~m%4kzG8J
int count = 0; LHGK!zI
String querySentence = "SELECT count(*) FROM zK]%qv]
+vY`?k`
user in class com.adt.po.User"; jYssz4)tp
Query query = getSession().createQuery I2!&=" 7@
pPqbD}p
(querySentence); hB1 iSm
count = ((Integer)query.iterate().next 5nlyb,"^g
j-\^
}K.&
()).intValue(); +=F);;!
return count; +/ d8d
} 2tTV5,(1
yvnrZ&x:
/* (non-Javadoc) hQrsZv:Q
* @see com.adt.dao.UserDAO#getUserByPage (3HgI
K0bmU(Xxp
(org.flyware.util.page.Page) ~V)VGGOL$v
*/ ;bu;t#
publicList getUserByPage(Page page)throws '48|f`8$
eh#
(}v
HibernateException { i7E7%~S
String querySentence = "FROM user in class i}12mjF
rs)aEmvC
com.adt.po.User"; e(5Px!B
Query query = getSession().createQuery ^C#bW<T
'g,
x}6
(querySentence); ]$%4;o4O
query.setFirstResult(page.getBeginIndex()) E8V\J
.setMaxResults(page.getEveryPage()); -|UX}t*
return query.list(); }E]&13>r
} o".O#^3H%
~]s"PV:|
} s~'C'B?
l3
Bc
g
G\+MT(&5
[1X5r<(W5
]uXsl0'`V
至此,一个完整的分页程序完成。前台的只需要调用 Ho*RLVI0U
n/|`Dz.
userManager.listUser(page)即可得到一个Page对象和结果集对象 =Qq^=3@h
N`:bvr
的综合体,而传入的参数page对象则可以由前台传入,如果用 `9NnL.w!
I ywx1ac
webwork,甚至可以直接在配置文件中指定。 GOgT(.5
]t0S_UH$
下面给出一个webwork调用示例: J:!Gf^/)
java代码: X Ow^"=Oa[
MPw7!G(qj
zb*4Nsda:
/*Created on 2005-6-17*/ FO3*[O
package com.adt.action.user; n ]g,)m
^qy-el
import java.util.List; _A~gqOe
E^ti!4{<
import org.apache.commons.logging.Log; SQ.Wj?W)
import org.apache.commons.logging.LogFactory; Dy'l]vN$
import org.flyware.util.page.Page; qt;Tfuo
t|,Ex 7
import com.adt.bo.Result; e;Z`&
import com.adt.service.UserService; q.Mck9R7
import com.opensymphony.xwork.Action; !S}Au Mw
K8we*
/** soCHwiE
* @author Joa =5#Jsn?U
*/ ~&jCz4M
publicclass ListUser implementsAction{
=)>q.R9
3`!KndY1
privatestaticfinal Log logger = LogFactory.getLog r\D8_S_
:cz]8~i\
(ListUser.class); c3BL2>c
NGzqiu"J
private UserService userService; {iteC
!~kzxY
private Page page; $S ("-3
=f|a?j,f~
privateList users; <;"=ah7A
''YjeX
/* (!=aRC.-
* (non-Javadoc) -JQg{A
* tS@/Bq('B
* @see com.opensymphony.xwork.Action#execute() D'+8]B
*/ W.<<azi
publicString execute()throwsException{ _QCI<|A
Result result = userService.listUser(page); K Hc +
page = result.getPage(); e4LNnJU\|
users = result.getContent(); QQcj"s
return SUCCESS; Ji=iq=S7
} r $2
AXI:h"so
/** {<n)zLy
* @return Returns the page. N/=3Bs0y-
*/ 1r4/McB
public Page getPage(){ =hlu,
B y
return page; bS6Yi)p
} s]>%_(5
1\kehCt
/** &9{BuBO[
* @return Returns the users. EC/R|\d?Un
*/ \]El%j4
publicList getUsers(){ iHB)wC`u
return users; DVH><3FF
} v,B\+q/
_Y=yR2O
/** >S]')O$c
* @param page ;{20Heuz
* The page to set. zBfBYhS-
*/ [t'"4
publicvoid setPage(Page page){ \:7EKzQ
this.page = page; //|Vj | =
} e:<>
Yq+
`Mg
"!n`
/** '~0&m]N
* @param users ] fB{
* The users to set. GAKJc\o
*/ <rs]@J'p
publicvoid setUsers(List users){ 470Pig>I8
this.users = users; DAi[3`C
} t1S~~FLE
Qt 2hb
/** {'(8<n57
* @param userService 8),Y|4
* The userService to set. TH &B9
*/ g~b'}^J
publicvoid setUserService(UserService userService){ %#~Wk|8} Q
this.userService = userService; 7&1: ]{_
} EK_^#b
} sP%.o7&n
>rubMGb
P9vROzXK
[G*mQ@G9
;U&VPIX$
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, rv:O|wZ
"5K:"m
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 bv "S(
DP_ \%(A
么只需要: jYv
!}
java代码: vCM'nkXY
1YxI q565
/_\4(vvf
<?xml version="1.0"?> /Y:Zqk3
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork HFOp4
^Tx1y[hw$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Z/x~:u_
5]E5 V@C
1.0.dtd"> ?$Pj[O^hl
~m7+^c@,
<xwork> vNIQc "\-
q`hg@uwA{`
<package name="user" extends="webwork- wlJ1,)n^2
#A!0KN;GC2
interceptors"> cf9y0
RiklwR#~r/
<!-- The default interceptor stack name \N30SG?o
DNPK1e3a{
--> <3KrhhH
<default-interceptor-ref K9R[
oB]b
bu-
RU(%
name="myDefaultWebStack"/> .@'Vz;&mQ
m\yO/9{h1
<action name="listUser" J7ln6 Y
k>"I!&#g
class="com.adt.action.user.ListUser"> gQ~4udla.
<param aH_&=/-Tz
Dp8(L ]6
name="page.everyPage">10</param> S(pfd2^
<result jo;n~>3P
/Q-!><riD
name="success">/user/user_list.jsp</result> /+u*9ZR&1
</action> 9YKEME+:
^^m%[$nw&r
</package> SzgVvmM}
f[w$3
</xwork> y4') !e
IWkBq]Y
})B)-8
^:BRbp37i
DWI!\lK
lk80)sTZ
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 hY!G>d{J
MEu-lM7v
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 7j+.H/2
t%)L8%Jr
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 vzL>ZBeZ
IX}l)t[:(
Xp'KQ1w)
{R K#W~h
rTH@PDk>)
我写的一个用于分页的类,用了泛型了,hoho UxW~yk
7?Fl [FW$
java代码: ;.Kzc3yz}
v [x`I;
*M{1RMc
package com.intokr.util; hRP0Djc
,#crtX
import java.util.List; A)xI.Q6
.+y#7-#6
/** q9OIw1xQr*
* 用于分页的类<br> k@w&$M{tPF
* 可以用于传递查询的结果也可以用于传送查询的参数<br> E^g6,Y:i9
* #\}hN~@F
* @version 0.01 X_h+\
7N>
* @author cheng er53?z7zP.
*/ t/3veDh@
public class Paginator<E> { "783F:mPh
privateint count = 0; // 总记录数 C oaqi`v4T
privateint p = 1; // 页编号 <,m}TTq
privateint num = 20; // 每页的记录数 f:TW<
privateList<E> results = null; // 结果 o` e~1
}Eav@3h6
/** P5N"7/PfW
* 结果总数 DT*/2TH*l
*/ *
08LW|:,
publicint getCount(){ 5+U~ZW0|+
return count; I0Vm^\8
} :7R\"@V4
E( TY%wO
publicvoid setCount(int count){ b`^$2RM&
this.count = count; +G?3j ,a\
} )T>a|.
3}"VUS0wh
/** <Sz9: hg-
* 本结果所在的页码,从1开始 U9JqZ!
* m_pK'jc
* @return Returns the pageNo. @FQ@*XD
*/ ;>PV]0bOm>
publicint getP(){ zIQ\_>
return p; (F
@IUbnl
} 8}U/fQ~
^0r@",
/** e@6}?q;
* if(p<=0) p=1 &P\T{d2"
* I} j!
!
* @param p S`NH6?/uH
*/ ~sM334sQ
publicvoid setP(int p){ zNBG;\W
if(p <= 0) QPBf++|
p = 1; +'[iyHBJ
this.p = p; 3mx7[Q
} blLX ncyD
cM55
vVd
/** er 97&5
* 每页记录数量 b7\nCRY
*/ 3c6<JW
publicint getNum(){ @.%ll n
return num; WhkE&7Gk
} +jHL==W&
nF7Ozxm#
/** ^f4qs
* if(num<1) num=1 ]+J]}C]\d
*/ ?A]:`l_"
publicvoid setNum(int num){ 6CCM7
if(num < 1) r1,RloyZS
num = 1; ,#s}nJ4
this.num = num; ](^xA`
} ]E,
=s;7T!7!
/** $[IuEdc/
* 获得总页数 `>K;S!z
*/ T;I a;<mfE
publicint getPageNum(){ 3xeW!~
return(count - 1) / num + 1; zV%U4P)Dao
} p`Ax)L\f
`2GHB@S"k
/** 2 &R-zG
* 获得本页的开始编号,为 (p-1)*num+1 ;hRo}
+\l
*/ [IiwpC
publicint getStart(){ SC'fT!
return(p - 1) * num + 1; 1;SWfKU?.
} c\n\gQ:LQ
`2{x8A
/** [03Aej
* @return Returns the results. `^RpT]S
*/ D (yRI
publicList<E> getResults(){ S?;&vs9j
return results; 9^ )=N=wV
} #p0vrQ;5f
I:[3x2H
public void setResults(List<E> results){ zxXm9zrLo
this.results = results; "`16-g97
} ]>&au8
{5:y,=Y
public String toString(){ Qb/qUUQO;0
StringBuilder buff = new StringBuilder FhW\23OC
5v8_ji#l[
(); vWwp'q
buff.append("{"); e;!si>N
buff.append("count:").append(count); g;vG6!;E\
buff.append(",p:").append(p); jeC3}BL}
buff.append(",nump:").append(num); DjtUX>e
buff.append(",results:").append `}"*i_0-5'
;ZB[g78%R%
(results); UZ v^3_,qz
buff.append("}"); nCJ)=P.d
return buff.toString(); G,%R`Xns
} A@+pvC&
.XTBy/(0
} ?~hC.5
JuS#p5E #
BG/M3