Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 tShyG!b
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 zM+eb| >cr
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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 p"ElO,\
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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 *CS2ndp
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分页支持类: nr>Os@\BU
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java代码: u>-pgu
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package com.javaeye.common.util; hH])0C
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import java.util.List; d&apu{
d ub%fs
publicclass PaginationSupport { [44C`x[8M+
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publicfinalstaticint PAGESIZE = 30; =}^J6+TVL
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privateint pageSize = PAGESIZE; [zMnlO
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privateList items; K]s*rPT/,
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privateint totalCount; ?D8+wj
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privateint[] indexes = newint[0]; 3rh@|fg)E
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privateint startIndex = 0; " _{o}8L
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public PaginationSupport(List items, int x!RpRq9
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totalCount){ 2?./S)x)
setPageSize(PAGESIZE); || 0n%"h>i
setTotalCount(totalCount); <yw(7
setItems(items); K|^'`FpPO
setStartIndex(0); /@qnEP%
} 6Qh@lro;y
U,e'vS{
public PaginationSupport(List items, int _dk/SWb)
iB0#Z_
totalCount, int startIndex){ M*n@djL$\~
setPageSize(PAGESIZE); _&xi})E^O]
setTotalCount(totalCount); lU&[){
setItems(items); KYN{Dh]-}
setStartIndex(startIndex); I`-N]sf^
} @&fAR2
?Q#yf8
public PaginationSupport(List items, int Q-7C'|
B;=-h(E}vJ
totalCount, int pageSize, int startIndex){ zC<k4[ .
setPageSize(pageSize); Lw_s'QNWR
setTotalCount(totalCount); !gbPxfH:6
setItems(items); qOM" ?av
setStartIndex(startIndex); *s1^s;LR
} oTLA&dy@
.m/$ku{/J
publicList getItems(){ `j)S7KN
return items; L$rMfeS
} ]R?{9H|jwE
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publicvoid setItems(List items){ (]gd$BgD
this.items = items; :+*q,lX8
} TVs#,
3I):W9$Qp
publicint getPageSize(){ T_3JAH e
return pageSize;
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} & cV$`L
, tb\^
publicvoid setPageSize(int pageSize){ DITo.PU
this.pageSize = pageSize; Ae[Na:G+
} {2,vxGi
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publicint getTotalCount(){ *JT,]7>
return totalCount; tkjQSz
} &Ay[mZQ 7
97 eEqI$#
publicvoid setTotalCount(int totalCount){ 7xU6Ll+p
if(totalCount > 0){ 43m@4Yb
this.totalCount = totalCount; 6#gS`X23Y
int count = totalCount / d.Im{-S
aTL u7C\-e
pageSize; ~dz,eB
if(totalCount % pageSize > 0) 2uZ4$_
count++; '^10sf`"
indexes = newint[count]; YDxEWK<
for(int i = 0; i < count; i++){ 1r?hRJ:'
indexes = pageSize * 0+dc
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i; d":GsI?3
} U_[<,JE
}else{ "kS!rJ[
this.totalCount = 0; T0TgV
} ($or@lfs
} Vl\8*!OL%
M%(^GdI#Vf
publicint[] getIndexes(){ #Ex NiFZ
return indexes; xP+`scv*m#
} *l{GD1ZDk
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publicvoid setIndexes(int[] indexes){ 2&o
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this.indexes = indexes; I 6-.;)McO
} v1O 1-aM
:}*
publicint getStartIndex(){ sFbN)Cx
return startIndex; <N'v-9=2jl
} V]Z!x.x"=y
``:+*4e9
publicvoid setStartIndex(int startIndex){ kWMz;{I5*w
if(totalCount <= 0) 7U647G(Sg
this.startIndex = 0; `p'682x I
elseif(startIndex >= totalCount) +S6(Fvp
this.startIndex = indexes ;lP/hG;`
? dh
[indexes.length - 1]; ;k|U2ajFJ
elseif(startIndex < 0) D8 BmC
this.startIndex = 0; {3`cSm6c
else{ RIdh],-
this.startIndex = indexes +=M N_
N> jQe
[startIndex / pageSize]; C116c"
} j@u]( nf
} vN9R.R
%5$)w;p.$'
publicint getNextIndex(){ mJNw<T4!/
int nextIndex = getStartIndex() + E^4}l2m_
O;lGh1.
pageSize; WRov7
if(nextIndex >= totalCount) [jEZ5]%
return getStartIndex(); iu.v8I;<
else B?
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return nextIndex; 9T#${NK
} K;Fs5|gFU
lW|`8ykp
publicint getPreviousIndex(){ W+Q^u7K
int previousIndex = getStartIndex() - SxI-pH'
Q].p/-[(
pageSize; (Cb;=:3G
if(previousIndex < 0) \"pp-str
return0; /Os6i&;
else A9_}RJ9
return previousIndex; !9t,#?!
} WCD)yTg:ES
dt|| nF
} .]w=+~h
[9^lAhX
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抽象业务类 '\M]$`Et
java代码: 8+@j %l j
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/** Marx=cNj
* Created on 2005-7-12 < Dt/JA(p
*/ U'aJCM
package com.javaeye.common.business; 19b@QgfWpb
es^@C9qt
import java.io.Serializable; QpD-%gN
import java.util.List; HA74s':FN
3O*^[$vM
import org.hibernate.Criteria; &u2H^ j
import org.hibernate.HibernateException; C2{*m{
D
import org.hibernate.Session; fSVb.MZa7
import org.hibernate.criterion.DetachedCriteria; ykYef
import org.hibernate.criterion.Projections; m+Kl
import zfw=U
\
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org.springframework.orm.hibernate3.HibernateCallback; :cvT/xhO
import ON9L+"vqv0
!oa/\p
org.springframework.orm.hibernate3.support.HibernateDaoS Tq?7-_MLC$
5=#2@qp
upport; uaE,F^p
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import com.javaeye.common.util.PaginationSupport; hdeI/4 B
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public abstract class AbstractManager extends 9ZNzC
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HibernateDaoSupport { ~)pso7^:
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privateboolean cacheQueries = false; V|G*9^Y
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privateString queryCacheRegion; 22'Ra[
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publicvoid setCacheQueries(boolean xXlx}C
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cacheQueries){ U(gYx@
this.cacheQueries = cacheQueries; (mplo|>
} ~O~iP8T
:{
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publicvoid setQueryCacheRegion(String zZ,"HY=jN
++n_$Qug
queryCacheRegion){ 0avtfQ +f
this.queryCacheRegion = w75Ro6y
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queryCacheRegion; IrUoAQ2xpG
} V?)YQB
aJ@lT&.
publicvoid save(finalObject entity){ fr'DV/T
getHibernateTemplate().save(entity); rJh$>V+ '
} d_!}9
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publicvoid persist(finalObject entity){ ;d<O/y,:4
getHibernateTemplate().save(entity); 5=\^DeM@
H
} KZO[>qC"R
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publicvoid update(finalObject entity){ Fi/`3A@68
getHibernateTemplate().update(entity); :}2T of2
} hBaF^AWW
znDpg{U(
publicvoid delete(finalObject entity){ Jd~M q9(
getHibernateTemplate().delete(entity); h^v#?3.@
} Ii#+JY0k
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publicObject load(finalClass entity, u{7->[=
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finalSerializable id){ * =*\w\
te
return getHibernateTemplate().load L1WvX6
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(entity, id); U&43/;<,
} X"vDFE`?
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publicObject get(finalClass entity, 3,EtyJ3[Bh
4]FS
jVO
finalSerializable id){ !Na@T]J
return getHibernateTemplate().get el\xMe^SY
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(entity, id); /E3~z0
} 'y5H%I!
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publicList findAll(finalClass entity){ '
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return getHibernateTemplate().find("from }u8g7Nj
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" + entity.getName()); -p%cw0*Y]C
} }u1h6rd `
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publicList findByNamedQuery(finalString \%B7M]P
8)MWC:
namedQuery){ !@*= b1
return getHibernateTemplate unNN&m#@
=**Q\Sl
().findByNamedQuery(namedQuery); %%#bTyF
} ;.<HpDfG_
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publicList findByNamedQuery(finalString query, uH(M@7"6_!
|Qb@.
finalObject parameter){ ,B /b>i
return getHibernateTemplate 8Q"1I7U
Q,Y^9g"B`~
().findByNamedQuery(query, parameter); E^A!k=>
} .|Yn[?(
+~*e B
publicList findByNamedQuery(finalString query, 17`-eDd
?*[35XUd
finalObject[] parameters){ wCV~9JTJ!
return getHibernateTemplate u?rX:KkS
bvHQ #:}H
().findByNamedQuery(query, parameters); bR1Q77<G\
} 7F_N{avr
Z$r7Hi
publicList find(finalString query){ ur7S
K(#
return getHibernateTemplate().find <:&{ c-f/
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(query); R,BINp
} h(GSM'v
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publicList find(finalString query, finalObject IxG7eX!
)/Gi-::
parameter){ g_!xD;0
return getHibernateTemplate().find sl(go^
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(query, parameter); ]rNxvFN*j
} xn@oNKD0
g>#}(u!PH
public PaginationSupport findPageByCriteria
|
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th<>%e}5c
(final DetachedCriteria detachedCriteria){ Oqt{ uTI~
return findPageByCriteria d(@ ov^e-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); f*IvaY
} _ysakn
!qHB?]
public PaginationSupport findPageByCriteria yjq|8.L[
G
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(final DetachedCriteria detachedCriteria, finalint D #7q3s
P2 qC[1hYH
startIndex){ *cCj*Zr]
return findPageByCriteria [wnaF|h
]=]MJ3_7
(detachedCriteria, PaginationSupport.PAGESIZE, ykH@kv Qt
9'e<{mlM
startIndex);
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} ):nC%0V
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public PaginationSupport findPageByCriteria R3LIN-g(
:zvAlt'q=
(final DetachedCriteria detachedCriteria, finalint ^<uQ9p^B
V]"pM]>3X
pageSize, Z}Q/u^Z
finalint startIndex){ a;nYR5f
return(PaginationSupport) WTjmU=<\
vS[\j
getHibernateTemplate().execute(new HibernateCallback(){ ;Bw3@c
publicObject doInHibernate ^R)]_
2$VSH&
(Session session)throws HibernateException { feeHXKD|
Criteria criteria = 1'iQlnMO@
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detachedCriteria.getExecutableCriteria(session); }RY Pr
int totalCount = -}( o+!nl
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((Integer) criteria.setProjection(Projections.rowCount "3|OB, <;:
-j:yE Z4Oy
()).uniqueResult()).intValue(); GU 9p'E
criteria.setProjection .2_xTt
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(null); :S7[<SwL
List items = 57]La^#
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criteria.setFirstResult(startIndex).setMaxResults p,uM)LD
h?}S|>9
(pageSize).list(); T&bB8tQk
PaginationSupport ps = a<>cbP
l<ZHS'-;8
new PaginationSupport(items, totalCount, pageSize, 2R^Eea
2+pXtP@O
startIndex); w>}n1Nc$G
return ps; ) ]<^*b>
} hJw]hVYa
}, true); &OEBAtc/
} ~?)y'?
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public List findAllByCriteria(final v6E5#pse8
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DetachedCriteria detachedCriteria){ \q24E3zS&
return(List) getHibernateTemplate tK'9%yA\
qSD3]Dv"
().execute(new HibernateCallback(){ 8DbP$Wwi
publicObject doInHibernate o]&P0 b
'WBhW5@
(Session session)throws HibernateException { a1[J>
Criteria criteria = `0w!&
=4U$9jo!;
detachedCriteria.getExecutableCriteria(session); ,JTyOBB<I
return criteria.list(); <1:I[b
} {i3=N{5b
}, true); ] \!,yiVeU
} `Hv"^o
i }Zz[b
public int getCountByCriteria(final !YlEXaS
x") Bmw$
DetachedCriteria detachedCriteria){ : t75iB=
Integer count = (Integer) aD6!x3c/
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getHibernateTemplate().execute(new HibernateCallback(){ cS@p`A7Tpo
publicObject doInHibernate -Ekf T_
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(Session session)throws HibernateException { </SO#g^r<
Criteria criteria = f.E{s*z>
*YX:e@Fm.a
detachedCriteria.getExecutableCriteria(session); 322-'S3<
return w vI
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F&3 :]1
criteria.setProjection(Projections.rowCount -~H
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ymnK `/J!Q
()).uniqueResult(); m`Z.xIA7;
} ycvgF6Me<
}, true); BGOS(
return count.intValue(); pL> Yx>
} MU:v& sk
} hgwS_L
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用户在web层构造查询条件detachedCriteria,和可选的 IF<T{/MA
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Ys?0hd<cn
A8AeM`
PaginationSupport的实例ps。 1-.i^Hal
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ps.getItems()得到已分页好的结果集 /#L4ec-'
ps.getIndexes()得到分页索引的数组 - ku8n%u
ps.getTotalCount()得到总结果数 yZNg[KH
ps.getStartIndex()当前分页索引 o"A?Aq
ps.getNextIndex()下一页索引 Fta=yH}
ps.getPreviousIndex()上一页索引 o>m*e7l,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 tn(6T^u
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,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 e"p){)*$
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一下代码重构了。 t~qAA\p}o
89P7iSV#*
我把原本我的做法也提供出来供大家讨论吧: 0U#m7j
9o]!D,u8=5
首先,为了实现分页查询,我封装了一个Page类: =vDDfPR
java代码: `}a-prT<f
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/*Created on 2005-4-14*/ 77]lpmC
package org.flyware.util.page; tZ*>S]qD
lACS^(
/** kn`O3cW/
* @author Joa r $ YEq5
* )2u_[Jc=
*/ UjyrmQf
publicclass Page { 9PaV*S(\TR
, 0?_?
GO
/** imply if the page has previous page */ ^$rqyWZYp
privateboolean hasPrePage; 5CH8;sMK
bZj5qjl`x
/** imply if the page has next page */ !QME!c>*$
privateboolean hasNextPage; GNW.n(a
'c
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/** the number of every page */ zqRps8=
privateint everyPage; ^
7)H;$
Z]Cd> u
/** the total page number */ IL?"g{w
privateint totalPage; *fLVzYpo
bcAk$tA2
/** the number of current page */ KsqS{VVCh
privateint currentPage; ;D%H}+Z
a,n#E!zT?w
/** the begin index of the records by the current 4]xD-sc
?-<>he
query */ $2Bll 5!]
privateint beginIndex; v9#F\ F/
RS2uk7MB
bY~V?yNgKM
/** The default constructor */ Iy5)SZ'
public Page(){ \"Qa)1|
uOh
} LF+E5{=:R
a?X@ D<.;
/** construct the page by everyPage v[jg|s&6"
* @param everyPage 3wPUP+)c7
* */ >3I|5kZ6
public Page(int everyPage){ ^t`0ul]c
this.everyPage = everyPage; y6H`FFqK
} Oz<#s{Z
:1v.Jk
/** The whole constructor */ Qr-,J_
public Page(boolean hasPrePage, boolean hasNextPage, crgVedx~}
UH((d*HX4
{GGP8
int everyPage, int totalPage, Y+0GJuBf
int currentPage, int beginIndex){ hANe$10=H
this.hasPrePage = hasPrePage; vVjk9_Ul
this.hasNextPage = hasNextPage; }yd!UU
this.everyPage = everyPage; 1`~.!yd8(
this.totalPage = totalPage; J M;WCV%NM
this.currentPage = currentPage; F^?DnZs
this.beginIndex = beginIndex; $Xs`'>,"
} YmHu8H_Q
o,/w E
/** z0&Y_Up+5
* @return ,y}~rYsP%
* Returns the beginIndex. Z
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*/ ,Z8)DC=
publicint getBeginIndex(){ \]3[Xw-$
return beginIndex; O]oH}#5b
} N]F}Z#h
ku#WQL
/** M5N#xgR
* @param beginIndex m@",Zr`f=
* The beginIndex to set. HzsQ`M4cA
*/ gIKQip<
publicvoid setBeginIndex(int beginIndex){ 3MDs?qx>s
this.beginIndex = beginIndex; HI[Pf%${
} WfYG#!}x
ss`Sl$
/** vb9C
* @return k=O
* Returns the currentPage. 7}pg7EF3z
*/ FJn.V1
publicint getCurrentPage(){ nW
oh(a
return currentPage; O-3a U!L
} :4r*Jju<V
AP ]`'C
/** P#[?Kfi
* @param currentPage >.uIp4@(
* The currentPage to set. wVc^l
*/ y<c7RK]
publicvoid setCurrentPage(int currentPage){ 9|m:2["|?
this.currentPage = currentPage; jVqpokWH
} COHook(:
/-+hMYe
/** 7j88^59
* @return thE9fr/
* Returns the everyPage. d)d0,fi?-
*/ v[)8 1uY
publicint getEveryPage(){ TYCjVxfu$
return everyPage; Q(x/&]7=V
} 0g#x QzE
Y+5aT(6O
/** bGxHzzU}
* @param everyPage D&qJ@PR
* The everyPage to set. oqzWL~
*/ I__a}|T%
publicvoid setEveryPage(int everyPage){ M
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this.everyPage = everyPage; PZI6{KOis
} m>*~tP
}i^$
li@
/** `Q[NrOqe"
* @return +zEyCx=8H
* Returns the hasNextPage. hS&.-5v
*/ 2UxmKp[
publicboolean getHasNextPage(){ #5iy^?N"w
return hasNextPage; [GcW*v
} yet~
yD@1H(yM
/** 69`*u<{PC
* @param hasNextPage )"7z'ar
* The hasNextPage to set. d\25
*/ #7KR`H
publicvoid setHasNextPage(boolean hasNextPage){ tYhcoV
this.hasNextPage = hasNextPage; g{f7} gTG
} !7p&n3dz
QlS_{XV
/** s'bTP(wl9
* @return ,5AEtoF
* Returns the hasPrePage. GInw7
*/ ZZi|0dG4;
publicboolean getHasPrePage(){ EK&0Cn3z
return hasPrePage; )JJF}m=
} vin3
i&k
Eu%E2A|`I
/** L\V`ou
* @param hasPrePage E()%IC/R
* The hasPrePage to set. Ys|SacWC
*/ M+b?qw
publicvoid setHasPrePage(boolean hasPrePage){ OL_jU2,fv
this.hasPrePage = hasPrePage; y>)c?9X
} cIcu=U
Ul}<@d9: B
/** 6;wKL?snO
* @return Returns the totalPage. T\bpeky~
* 2'-84
*/ |sEuhP\A3
publicint getTotalPage(){ F!p;]B
return totalPage; cDK)zD
} Vhr 6bu]
UcH#J &r
/** N(2M
w:}
* @param totalPage ]&dPY[~,/i
* The totalPage to set. ;>S|?M4GZ
*/ Q7i(M >|O
publicvoid setTotalPage(int totalPage){ be$']}cP
this.totalPage = totalPage; 9A/bA|$
} 9%bErMHL
*LuRo
} 4C;y2`C
9,JWi{lIv
Et0)6^-v
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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 ) .KMZ]
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个PageUtil,负责对Page对象进行构造: /)kx`G_
java代码: ).A9>^6?{
@th94tk,
:8HVq*itS
/*Created on 2005-4-14*/ [rL 8L6,!
package org.flyware.util.page; D@:'*Z(
_pDfPLlY&
import org.apache.commons.logging.Log; dCo3 VF"u
import org.apache.commons.logging.LogFactory; U3`?Z`i(
Eggu-i(rD
/** Pn6~66a6
* @author Joa %(W8WLz}
* L
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*/ B*w]yL(
publicclass PageUtil { ),[@NK&=
`xx3JQv[
privatestaticfinal Log logger = LogFactory.getLog &]shBvzl^
Y=g]\%-PB
(PageUtil.class); h=JW^\?\]
>5?:iaq
z
/** 7[UD;&\k
* Use the origin page to create a new page \ 9iiS(e
* @param page gNc;P[
* @param totalRecords gS@<sO$d>
* @return y.6/x?Qc
*/ Z0<s
-eN:
publicstatic Page createPage(Page page, int w=a$]`
.U44p*I
totalRecords){ S#r|?GYua
return createPage(page.getEveryPage(), x 4sIZe+
0L1sF'ZN
page.getCurrentPage(), totalRecords); +l.LwA
} cc:$$_'L
<(B|g&A
/** #Sx
* the basic page utils not including exception WiZTE(NM`
.l5-i@=W
handler . UH'U\M
* @param everyPage Nu\<Xr8
* @param currentPage "tK|/R+
* @param totalRecords %>6ilGQ+
* @return page e-[PuJ
*/ SynRi/BRmw
publicstatic Page createPage(int everyPage, int ?u/UV,";y
{?2|rv)
currentPage, int totalRecords){ 'W>y v
everyPage = getEveryPage(everyPage); <RZqs
currentPage = getCurrentPage(currentPage); #f HnM+
int beginIndex = getBeginIndex(everyPage, +8x_f0<
DvB{N`COd
currentPage); '$EyVu!
int totalPage = getTotalPage(everyPage, XgM&0lVT
G%AO%II
totalRecords); EWgJ"WTF
boolean hasNextPage = hasNextPage(currentPage, 8lGM>(:o
,<)D3K<
totalPage); ZoSyc--Bv
boolean hasPrePage = hasPrePage(currentPage); pek=!nZ
4d}=g]P
returnnew Page(hasPrePage, hasNextPage, /fQ}Ls\
everyPage, totalPage, ".waCt6
currentPage, +^&i(7a[?
R5%CK_
beginIndex); [#RFdn<
} 5E1`qof
",J&UTUh
privatestaticint getEveryPage(int everyPage){ `b] wyP
return everyPage == 0 ? 10 : everyPage; &R?to>xr\
} 6H5o/)Q~
au/LoO#6Ro
privatestaticint getCurrentPage(int currentPage){ VJT /9O)Z|
return currentPage == 0 ? 1 : currentPage; Y_n3O@,
} -aS@y.z
QB!_z4UJ_;
privatestaticint getBeginIndex(int everyPage, int 3\
,t_6}
c5b}q@nH
currentPage){ ,\c V,$
return(currentPage - 1) * everyPage; i$Kx@,O8t
} CCol>:8{P
/3K)$Er
privatestaticint getTotalPage(int everyPage, int 19c_=$mV
&qWB\m
totalRecords){ -gS9I^
int totalPage = 0; *hJWuMfY,
#ojuSS3
if(totalRecords % everyPage == 0) 2f@Cy+W'[
totalPage = totalRecords / everyPage; NN1}P'6Ha
else m-ibS:
totalPage = totalRecords / everyPage + 1 ; UZrEFpi
O(!;7v}
return totalPage; h6^|f%\w*i
} sgGA0af
-,T!/E
privatestaticboolean hasPrePage(int currentPage){ V,0$mBYa
return currentPage == 1 ? false : true; Wf"GA i
} OKK Ko`RN
sQkijo.
privatestaticboolean hasNextPage(int currentPage, s-+-?$K
"~._G5i.
int totalPage){ {i?G:K
return currentPage == totalPage || totalPage == ge.>#1f}
KK2YT/K$SG
0 ? false : true; !4=_l6kg~+
} ^v'0\(H?P
yiI
oqvP
{wj%WSQj/y
} L6fbR-&Lt
/|i*'6*
A%HIfSzQBS
$p4e8j[EJ
G9LWnyQt
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。 6kLy!QS
/j}Tv.'d
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 *AQ3RA 8
: [328X2
做法如下: @6tczU}ak
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;-@: }/
6SH0
y
的信息,和一个结果集List: *jWh4F,
java代码: f$kbb6juL
n8=Dzv0
8IQ}%|lN
/*Created on 2005-6-13*/ :i& 9}\|,
package com.adt.bo; 4K~=l%l
n7K%lj-.P
import java.util.List; 0F%8d@Y2
d=%NFCIV
import org.flyware.util.page.Page; ncOgSj7e
zPqJeYK
/** }F!Uu
KR
* @author Joa 2w8cJadT'p
*/ ej&.tNvq
publicclass Result { ,52 IR[I<T
`y^\c#k
private Page page; amC)t8L?
Ao}<a1f
private List content; dVj2x-R)
Nr `R3(X
/** LO)!Fj4|
* The default constructor Ui
(nMEon
*/ Fj~suZ`
public Result(){ D6Aa5&rO+
super(); =<p=?16
x
} BO7HJF)a
c1s&
/** 2&n6:"u|
* The constructor using fields f7\X3v2W}3
* O!f37n-TB
* @param page 4c 8{AZ
* @param content l1'v`!
*/ k)*apc\W
public Result(Page page, List content){ =Q<7[
this.page = page; +
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this.content = content; {R(CGrI
} mHW%:a\L
Gt*K:KT=L
/** 0Atha>w^o~
* @return Returns the content. gveJ1P
*/ E] /2u3p
publicList getContent(){ .x,y[/[[)
return content; OzrIiahz/
} u%z'.#r; a
BQ Vro;#Jc
/** XF)N_}X^
* @return Returns the page. 6d;}mhH
*/ Bt}90#
public Page getPage(){ cpP}NJb0;%
return page; ~ E6e~
} y.D+M$f
N WF h<
/** =KOi#;1
* @param content v/rBjUc+X
* The content to set. dt"/4wCO
*/ lqmQQ*Z
public void setContent(List content){ 2{~`q
this.content = content; >\<eR]12
} Y`]P&y
'#3FEo
/** Y=G`~2Pr=
* @param page )M+po-6$1
* The page to set. {!wW,3|Pu
*/ 7AT8QC`u
publicvoid setPage(Page page){ VED~v#.c
this.page = page; *`u|1}h|
} iw/~t
} oJQS&3;/r
/"D,gn1S*
cb]X27uww
YFJaf"?8g
57{T
p:|
2. 编写业务逻辑接口,并实现它(UserManager, d%qi~koN_
k6ry"W3
UserManagerImpl) YAT@xZs-
java代码: n5UUoBv
EniV-Uj\D
H i8V=+
/*Created on 2005-7-15*/ sGhw23
package com.adt.service; &-Ch>:[
J(d+EjC
import net.sf.hibernate.HibernateException; 9MZ)-
hDB(y4/
import org.flyware.util.page.Page; >JE+g[$@
LJPJENtFIs
import com.adt.bo.Result; }g-w[w 7p
eo4z!@pRN
/** zNt//,={
* @author Joa lAi5sN)|$
*/ [HWVS
publicinterface UserManager { |X:`o;Uma
uXFI7vV6P
public Result listUser(Page page)throws .W~XX
K
|=o -
HibernateException; iE"]S )
;y\/7E
} &2XH.$Q
mm+V*L{x
5)XUT`;'){
ynM~&]fk#k
&t<gK
D
java代码: JYw?
_"Ym]y28li
DKfpap}8u
/*Created on 2005-7-15*/ VNT?
package com.adt.service.impl; uoE+:,P
])F+ C/Px1
import java.util.List; B7'#8heDh
$}tF66d
import net.sf.hibernate.HibernateException; oH0g>E;
jnOnV1I"
import org.flyware.util.page.Page; q1u$Sm
import org.flyware.util.page.PageUtil; GNv{Ij<
w%qnH e9
import com.adt.bo.Result; {f`Y\_r$@
import com.adt.dao.UserDAO; @, fvWNI
import com.adt.exception.ObjectNotFoundException; Za!KM
import com.adt.service.UserManager; `mteU"{bx
3>7{Q_5
/** z4BU}`;b3t
* @author Joa MnFrQC
*/ 0M;El2
P$
publicclass UserManagerImpl implements UserManager { hR|xUp
\\:%++}J
private UserDAO userDAO; SS%Bde&<{
]N]Fb3
/** c]x-mj =
* @param userDAO The userDAO to set. "1Hn?4nz5
*/ kJuG haO
publicvoid setUserDAO(UserDAO userDAO){ dpq(=s`s
this.userDAO = userDAO; wg)Bx#>\L:
} B/a`5&G]
)C?H m^#
/* (non-Javadoc) a+lNXlh=
* @see com.adt.service.UserManager#listUser %$zak@3%'
|%5Aku0`s
(org.flyware.util.page.Page) iYT?6Y|+
*/ )tJaw#Mih
public Result listUser(Page page)throws !Ltx2CB2]
)=}qAVO8
HibernateException, ObjectNotFoundException { ',`Qx{tQ)
int totalRecords = userDAO.getUserCount(); aE)1LP
if(totalRecords == 0) `)8~/G%
throw new ObjectNotFoundException _GxC|d
f9#srIx+
("userNotExist"); {'+{ASpO!
page = PageUtil.createPage(page, totalRecords); `+< ^Svou
List users = userDAO.getUserByPage(page); >2>/
q?
returnnew Result(page, users); HN`qMGW^
} q%d'pF
?m~1b_@A{
} P^F3,'N
0/DO"pnL@
Ng;?hT w
~Sb)i f
g#74c'+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 [7PC\
fWA#n
询,接下来编写UserDAO的代码: 1SS1P0Ur
3. UserDAO 和 UserDAOImpl: WxYEu+_
java代码: Y J,"@n_
^`lD w
Ig!0A}f
/*Created on 2005-7-15*/ EMe1!)
package com.adt.dao; t=}]4&Yp
rZ(#t{]=!
import java.util.List; u*%mUh
L9e<hRZ$
import org.flyware.util.page.Page; 3HuocwWbz
Jf=V<
import net.sf.hibernate.HibernateException; u8JH~b
|)>+&
xk
/** %pxJ2 7Q
* @author Joa rlh:|#GTJ
*/ iTdamu`L
publicinterface UserDAO extends BaseDAO { 2>X yrG
mgH~GKf^
publicList getUserByName(String name)throws {9 |*au(K
;|XX^
HibernateException; MXl_{8
fCNQUK{Gs5
publicint getUserCount()throws HibernateException; khR[8j..
RrBG=V
publicList getUserByPage(Page page)throws 4=^Ha%l
k*2khh-
HibernateException; I:DAn!N-A*
q,7W,<-
} cX1?4e8
pFMjfWD,C
5V(#nz
dKEy6C"@
<f:(nGj
java代码: -J6`
V[%IU'{:
6`'g ${U
/*Created on 2005-7-15*/ yph@H!@
package com.adt.dao.impl; aJ=)5%$6kc
`Mg3P_}=
import java.util.List; qF(i1#
8q]"CFpa
import org.flyware.util.page.Page; +<@1)qZ(E
rkWy3X{%2<
import net.sf.hibernate.HibernateException; 7]?y
_%kT
import net.sf.hibernate.Query; <f}:YDY'
dEMv9"`*!
import com.adt.dao.UserDAO; ~~&Bp_9QXN
$D65&R
/** bYQ@!
* @author Joa w#a`k9y
*/ jdVj
FCl^#
public class UserDAOImpl extends BaseDAOHibernateImpl 1Z_w2D*
1jKj'7/K
implements UserDAO { wpN [0^M-0
zobFUFx
/* (non-Javadoc) P}Mu|AEG
* @see com.adt.dao.UserDAO#getUserByName a(fiW%eFb
Vr&
GsT
(java.lang.String) >mvE[iXRG?
*/ .%J<zqk-
publicList getUserByName(String name)throws gGCr~.5
P5G0fq7
HibernateException { DsxNg
String querySentence = "FROM user in class |*ZM{$
.#tA .%
com.adt.po.User WHERE user.name=:name"; !a V:T&6
Query query = getSession().createQuery N@Ap|`Ei
T:%0i8p
(querySentence); D` cy.},L
query.setParameter("name", name); {%('|(57
return query.list(); 8f~*T
} !W&|kvT^
U74L:&yLI
/* (non-Javadoc) 9_svtO ]P
* @see com.adt.dao.UserDAO#getUserCount() @S~n^v,)
*/ F&7Z(
publicint getUserCount()throws HibernateException { vnbY^ASdw
int count = 0; t6e6v=.Pg
String querySentence = "SELECT count(*) FROM Y/m-EL
)iIsnM
user in class com.adt.po.User"; t vW0 W
Query query = getSession().createQuery $u,A/7\s
B&KIM{j\
(querySentence); BUi,+NdIk
count = ((Integer)query.iterate().next Cv>~%<
h0 %M+g
()).intValue(); #NMQN*J>D
return count; }YC=q
} w0yzC0yBk
`;R$Ji=>
/* (non-Javadoc) I%[Tosud<
* @see com.adt.dao.UserDAO#getUserByPage K4|fmgcy.
ebL0cK?
(org.flyware.util.page.Page) 75P!`9bE
*/ &,Rye Q
publicList getUserByPage(Page page)throws 7?_gm>]a
k&K'FaM!
HibernateException { K",Xe>
String querySentence = "FROM user in class v'`qn
rOUQg_y
com.adt.po.User"; h;(mb2[R
Query query = getSession().createQuery F!I9)PSj
(?T{^Hg
(querySentence); 3-;<G
query.setFirstResult(page.getBeginIndex()) SFP?ND+7
.setMaxResults(page.getEveryPage()); *fy aAv
return query.list(); $i3`cX)g
} bFA
lC
y~t
e!C
} "f3mi[
(yT&&_zY4
h{~GzrL*
g[ @Q iy
D7thLqA
至此,一个完整的分页程序完成。前台的只需要调用 ei]Q<vT6
8ce'G"
b
userManager.listUser(page)即可得到一个Page对象和结果集对象 ^{8CShUCv
X`E}2|q'
的综合体,而传入的参数page对象则可以由前台传入,如果用 {~\:4
r|bGn#^
webwork,甚至可以直接在配置文件中指定。 Ka)aBU9
1csbuR?
下面给出一个webwork调用示例: o {q8An)
java代码: H-m).^
JNvgUb'U
n0':6*oGW
/*Created on 2005-6-17*/ :IsJE6r
package com.adt.action.user; YD~(l-?"
eXLdb-
import java.util.List; 7D8 pb0`;J
fo9V&NE
import org.apache.commons.logging.Log; hJ4 A5m.
import org.apache.commons.logging.LogFactory; u!VrMH
import org.flyware.util.page.Page; `B3YP1
^#w9!I{4.
import com.adt.bo.Result; 9(a*0H
import com.adt.service.UserService; PI*Z>VE?
import com.opensymphony.xwork.Action; MpJ3*$Dr
E%f!SD
/** G"
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* @author Joa *li5/=UC5*
*/
hJ8B&u(
publicclass ListUser implementsAction{ .b2%n;_>.
'Ze&
LQ
privatestaticfinal Log logger = LogFactory.getLog ~dsx|G?p
[H`5mY@
(ListUser.class); ${t$:0R,h
]jmZ5h#[
private UserService userService; _Mh..#)`[
=k!F`H`/%'
private Page page; 2:[G4
Sc]h^B^7
privateList users; @Js@\)P79
FT gt$I
/* )Z:maz
* (non-Javadoc) OtT*)8*c
* Zc9S[ivq
* @see com.opensymphony.xwork.Action#execute() eQ#"-i
*/ LXc;`]
publicString execute()throwsException{ _ UF'Cf+Y
Result result = userService.listUser(page); EiA_9%<
page = result.getPage(); ar`}+2Qh0
users = result.getContent(); 2m&?t_W
return SUCCESS; /w*HxtwFmD
} eX^ F^(
M!PK3
/** t |:XSJ9
* @return Returns the page. Fow{-cs_p
*/ ef:Zi_o
public Page getPage(){ !-B|x0fs
return page; }OgZZ8-_M
} ab_EH}j1\q
vb\R~%@T,
/** {\k:?w4
* @return Returns the users. R
<u\
-
*/ Xpmi(~n
publicList getUsers(){ 4?x$O{D5?{
return users; &y2DI"Ff
} x Sv@K5"8!
MWn[]'TpH
/** l_&T)Ei
* @param page ?d)eri8,
* The page to set. YQ}IE[J}v
*/ c/G^}d%
publicvoid setPage(Page page){ +|O&k
this.page = page; ? ,!C0t s
} qd
[Z\B
X5P1wxk'
/** RJOyPZ]
* @param users P76QHBbl
* The users to set. k8ymOx
*/ wpJfP_H
publicvoid setUsers(List users){ wOl]N2<
this.users = users; iM{aRFL
} h{VGhkU9f
pW2-RHGJY
/** !ma'*X
* @param userService ]~m2#g%
* The userService to set. Ktf lbI!
*/ Ni61o?]Nj
publicvoid setUserService(UserService userService){ mk?F+gh
this.userService = userService; EnjSio0
} </h}2x
} z
Q11dLjs
.\AbE*lZ#
&qeMYYY
;c>IM]
4p/d>DTiM
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, 4ko(bW#jL
=a./HCF
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 7Dx<Sr!
C5'#0}6i
么只需要: ;jT@eBJ
java代码: Vg?
1&8>
;kF+V*
GMoE,L
<?xml version="1.0"?> Nc[u?-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K(p6P3Z
%>k$'UWzK
1.0//EN" "http://www.opensymphony.com/xwork/xwork- kT4Tb%7KM
;PX>] r5U0
1.0.dtd"> lhx]r}@'MC
>[gNQJ6
<xwork> gLPgh%B4
s4{ >7`N2
<package name="user" extends="webwork- Ba]^0Y
u
[5Pin>]z
interceptors"> 2t"&>1
."JtR
<!-- The default interceptor stack name co%-d
6"Rw&3D?
--> +d,Z_ 6F
<default-interceptor-ref si3@R?WR6*
=G%L:m*
name="myDefaultWebStack"/> XVkCYh4,
Q"sszz
<action name="listUser" 4BAG GD2
RL3G7 ;X
class="com.adt.action.user.ListUser"> >-Q=o,cl%3
<param A"~4|`W
{Zy)p%j8
name="page.everyPage">10</param> IH~[/qNk
<result <ULydBom
'z3I*[!
name="success">/user/user_list.jsp</result> ^N:bT;;$nZ
</action> Q !G^CG
E >lW'
</package> d;O4)8>
=-|,v*
</xwork> O4fl$egQU
%.VFj7J
5]yby"Z?}
whvvc2
eUE(vn#
'?MT"G
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 C{8(ew
z1 P=P%F
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 rRzc"W}K+
Ov PTgiI!N
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 "s5[w+,R
@fG'X
rWB/#m
Dk`(Wgk2
fjm(C#^-
我写的一个用于分页的类,用了泛型了,hoho s+OXT4>+
jQrw^6C
java代码: p;<brwN
YPNG9^Y
IG=# 2 /$
package com.intokr.util; |#?:KvU97E
#J09Eka;J
import java.util.List; -{rUE +
D>efr8Qd@
/** s'JbG&T[J
* 用于分页的类<br> Vmf!0-
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ]ovb!X_
* hO] vy>i;
* @version 0.01 H$={i$*,Y
* @author cheng M"Q{lR
*/ 7S]<?>*
public class Paginator<E> { 1'"TO5
privateint count = 0; // 总记录数 _[t:Vme}v
privateint p = 1; // 页编号 7@uhw">mX
privateint num = 20; // 每页的记录数 ?,0 a#lG
privateList<E> results = null; // 结果 *$yU|,
's_[#a;Vp
/** qaZQ1<e
* 结果总数 p]erk
*/ ]
g]^^
publicint getCount(){ {f:%+h
return count; Ny2. C?2
} pW4$$2S?9
/U5!]7&gB
publicvoid setCount(int count){ >#~>!cv6D
this.count = count; YwnYTt
} oZwu`~h Y
hWD%_"yhd
/** "9bd;Tt:
* 本结果所在的页码,从1开始 vkE a[7
* ]<Kkq!
* @return Returns the pageNo. "';K$&,[
*/ GLtd6; V
publicint getP(){ SA[wFc
return p; iw\yVd^]:k
} ^M6R l0
%v)O!HC}
/** h 1REL^!c
* if(p<=0) p=1 OH/!Ky\@
* 6Mh"{N7
* @param p Zb}U 4
*/ r"xs?P&/$
publicvoid setP(int p){ f6k=ew
if(p <= 0) S}/5W
p = 1; !M@jW[s
this.p = p; PB(I3R9
} $QB/n63
Ev>P|kV&A
/** @
q:S]YB
* 每页记录数量 &5d~ODO
*/ ;(r,;S_`0
publicint getNum(){ 6%L#FSI
return num; !j%MN{#a
} 51-@4E2:l:
Fv$oXg/
/** :e rfs}I
* if(num<1) num=1 V
0z`p"
*/ r@u8QhD
publicvoid setNum(int num){ K;j0cxl
if(num < 1) 45A|KaVpg
num = 1; gJBw6'Z
this.num = num; <\`qRz0/
} F_ -}GN%
fR>"d<;T
/** Q4ZKgcC
* 获得总页数 @id!F<+%oD
*/ H;{IOBo
publicint getPageNum(){ ]8f$&gw&A
return(count - 1) / num + 1; -BcnJK0
} {R8)DK
sZPyEIXie
/** 9%Qlg4~<s
* 获得本页的开始编号,为 (p-1)*num+1 08G${@D+X0
*/ U(/8dCyyY
publicint getStart(){ V@o#" gZ
return(p - 1) * num + 1; TpcJ1*t
} oLIgj,k{*
2@,rIve
/** EslHml#
* @return Returns the results. N"8'=wB
*/ Y^tUcBm\
publicList<E> getResults(){ =z!/:M
return results; unc8WXW
} L<k(stx~
46U*70
public void setResults(List<E> results){ RQYD#4|
this.results = results; o1R:1!"2
} QjOY1Xze
sB8v:
public String toString(){ MO@XbPZB
StringBuilder buff = new StringBuilder bT15jNa
>|aVGY
(); KAg-M#
buff.append("{"); 9AJ"C7
buff.append("count:").append(count); _N:GZLG
buff.append(",p:").append(p); UM2yv6:/
buff.append(",nump:").append(num); =[,EFkU?B
buff.append(",results:").append MdhD "Q
Q zp!)i
(results); kMZo7 y
buff.append("}"); I%l2_hs0V
return buff.toString(); k)R~o
b
} SP"t2LTP
*Hz]<b?
} fd$nAE
@MP ;/o+
9[R+m3V/`