Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 je2_.^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mOn_#2=KF
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j
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 DyGls8<\!
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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 (A6~mi r!
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。 [{BY$"b#:
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分页支持类: g]2L[4
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java代码: wL
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package com.javaeye.common.util; D5?8`U
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n%J=!z3
import java.util.List; BrwC9:
@&O4a2+
publicclass PaginationSupport { HRDpFMA/~
p.=9[`
publicfinalstaticint PAGESIZE = 30; wLXJ?iy3
}A24;'}
privateint pageSize = PAGESIZE; M]/aW
# Q^".#
privateList items; }a6t <m`V
bP9ly9FH
privateint totalCount; @3O)#r}\
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privateint[] indexes = newint[0]; SXOAa<u5
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privateint startIndex = 0; D@*<O=_D(
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public PaginationSupport(List items, int 71c[`h*0{
7D#y
totalCount){ iT4*~(p 3
setPageSize(PAGESIZE); bhpku=ov
setTotalCount(totalCount); ] [MtG
setItems(items); L#UR>Z#9
setStartIndex(0); +ZOiL[rS
} uD&B{c+a
X&qx4DL
public PaginationSupport(List items, int lZcNio
UPfO;Z`hJ
totalCount, int startIndex){ s.}K?)mH
setPageSize(PAGESIZE); 2(xC|
setTotalCount(totalCount); E
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setItems(items); 8I#ir4z#<
setStartIndex(startIndex); P#~B@d
} Vi8A4
@ivd|*?k0
public PaginationSupport(List items, int L9D`hefz
d7X&3L%Oq
totalCount, int pageSize, int startIndex){ FI$:R
setPageSize(pageSize); 'RK"/ZhqE
setTotalCount(totalCount); PX
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setItems(items); Fr8GGN~/
setStartIndex(startIndex); RU:Rt'
} e /JQ #A
%x$U(I}
publicList getItems(){ y~
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return items; `um,S
} ^hC'\09=c
MePD:;mm^
publicvoid setItems(List items){ $>XeC}"x68
this.items = items; 37/n"\4
} `@h|+`h
+tqErh?Al
publicint getPageSize(){ aKbmj
return pageSize; %T{]l;5
} }Q/onBt
WVbrbs4
publicvoid setPageSize(int pageSize){ fSuykbZ
this.pageSize = pageSize; hi0HEm\
} 8vY-bm,e
G21o@38e
publicint getTotalCount(){ yp.K-
return totalCount; `Z?wj@H1`
} smQ^(S^
2@D`^]]
publicvoid setTotalCount(int totalCount){ &r5q,l&@n
if(totalCount > 0){ 5yy:JTAH5
this.totalCount = totalCount; `C+<!)2
int count = totalCount / ;Ba%aaHl
LwH#|8F
pageSize; 86r5!@WN
if(totalCount % pageSize > 0) KQdIG9O+6
count++; <$(B [T
indexes = newint[count]; $7S"4rou
for(int i = 0; i < count; i++){ k"(]V
indexes = pageSize * 0M_oFx
xAQtX=FoX+
i; C9n%!()>
} .V?:&_}_I6
}else{ &_ekA44E
this.totalCount = 0; |^pev2g
} ]k0
jmE
} |"3<\$[
7;"0:eX
publicint[] getIndexes(){ 11[lc2
return indexes; :gh[BeqQ)
} ?{{w[U6NE
_IYaMo.n
publicvoid setIndexes(int[] indexes){ %BqaVOKJ"f
this.indexes = indexes; y>^^.
} IHl q27O
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publicint getStartIndex(){ 5'~_d@M
return startIndex; _kj]vbG^;
} "s*-dZO
:d36oiHKu
publicvoid setStartIndex(int startIndex){ 7 F^d-
if(totalCount <= 0) }h5i Tc
this.startIndex = 0; )+E[M!34
elseif(startIndex >= totalCount) >qjV{M
this.startIndex = indexes }]?Si6_ZZ
1 DWoL}Z
[indexes.length - 1]; La26"C"X
elseif(startIndex < 0) P3$eomX'
this.startIndex = 0; <B"sp r&1
else{ kI{DxuTad
this.startIndex = indexes 4q$~3C[
`@]s[1?f
[startIndex / pageSize]; c7Z4u|G
} Zp_(vOc
} d2
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RU )35oEV|
publicint getNextIndex(){ Y?VbgOM)
int nextIndex = getStartIndex() + {f!/:bM
ie}OZM
pageSize; 5,RUPaE
if(nextIndex >= totalCount) R?2sbK4Cz
return getStartIndex(); OZ,kz2SF#
else p5Q]/DhG
return nextIndex; f^WTsh]
}
--$o$EP`
v<qh;2
publicint getPreviousIndex(){ '=\}dav!
int previousIndex = getStartIndex() - I$n=>s
d"$8-_K
pageSize; "n-'?W!
if(previousIndex < 0)
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return0; Kz4S6N c
else L+%"ew
return previousIndex; )
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} N+-Tp&:wY
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} 1SQATUV
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j
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l^B.iB
抽象业务类 I$Nh|eM
java代码: o_b[ *
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/** "cH RGJG#
* Created on 2005-7-12 TBhM^\z
*/ "q4tvcK.
package com.javaeye.common.business; bdUPo+
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import java.io.Serializable; )^h6'h`
import java.util.List; cH]tZ$E`
dn6B43w
import org.hibernate.Criteria; ntiS7g e1
import org.hibernate.HibernateException; T X`X5j
import org.hibernate.Session; xS18t="
import org.hibernate.criterion.DetachedCriteria; l{3B}_,
import org.hibernate.criterion.Projections; t<%0eu|
import 8OfQ :
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org.springframework.orm.hibernate3.HibernateCallback; yoi4w 7:
import LHAlXo;
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org.springframework.orm.hibernate3.support.HibernateDaoS ?I.9?cQXZ
x^f<G
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upport; QaX.Av
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import com.javaeye.common.util.PaginationSupport; 5:Qz
#F*|@
public abstract class AbstractManager extends o3ZN0j69|
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HibernateDaoSupport { Vs>Pv$kW
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privateboolean cacheQueries = false; v1h(_NLI!
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privateString queryCacheRegion; ?5|;3N/zt
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publicvoid setCacheQueries(boolean ,N/@=As9$
FR(W.5[
cacheQueries){ =O/Bte.
this.cacheQueries = cacheQueries; <QtZ6-;_f
}
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publicvoid setQueryCacheRegion(String 8$Q`wRt(%
:-&|QVH
queryCacheRegion){ -"(*'hD
this.queryCacheRegion = .@dC]$2=
61\u{@o$
queryCacheRegion; wI#8|,]"z
} 7AG|'s['=
,RP-)j"Wff
publicvoid save(finalObject entity){ l,wlxh$}(
getHibernateTemplate().save(entity); tz1@s nes
} >hKsj{=R7
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publicvoid persist(finalObject entity){ mDD.D3RS
getHibernateTemplate().save(entity); fV:15!S[
} tobE3Od4
LvG.ocCG
publicvoid update(finalObject entity){ F[qXIL)
getHibernateTemplate().update(entity); t2&kGf"
} -K"'F`;W
}v1wpv/b(
publicvoid delete(finalObject entity){ iT@`dEZ.
getHibernateTemplate().delete(entity); >WLPE6E
} |1tKQ0jg
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publicObject load(finalClass entity, Z\$HgG
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finalSerializable id){ f^%3zWp|-
return getHibernateTemplate().load .soCU8i3
}A9#3Y|F
(entity, id); Xj?Wvt
} Z[vx0[av&
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publicObject get(finalClass entity, S :HOlJze
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finalSerializable id){ {1GJ,['qL
return getHibernateTemplate().get ;qx#]Z0 <
8&QST!JGSX
(entity, id); vz^ ] g
} R!VfTAv
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5:
publicList findAll(finalClass entity){
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return getHibernateTemplate().find("from 37bMe@W
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" + entity.getName()); *4O=4F)x
} dQX-s=XJ
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publicList findByNamedQuery(finalString _h%Jf{nu
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namedQuery){ u#05`i:Z
return getHibernateTemplate whI{?NP
.j6udiv5
().findByNamedQuery(namedQuery); $C16}^
} OT#@\/>
m l`xLZN>L
publicList findByNamedQuery(finalString query, E4#{&sRT
,f03TBD}
finalObject parameter){ OM'iJB6=
return getHibernateTemplate 8jK=A2pTa
b[%@3 }E
().findByNamedQuery(query, parameter); ZlV
} $`pf!b2Z
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publicList findByNamedQuery(finalString query, x07 =
}2
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finalObject[] parameters){ [o^$WL?c
return getHibernateTemplate oRfb4+H&
Z'o0::k
().findByNamedQuery(query, parameters); 31n"w;
} /08FV|tX)
2:LUB)&i
publicList find(finalString query){ %$BRQ-O
return getHibernateTemplate().find 7uBx
x;ik
(query); K'OG-fn;
} g&RpE41x
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publicList find(finalString query, finalObject l;$F[/3a
pj'gTQ),0
parameter){ <O
jK $KV
return getHibernateTemplate().find N=mvr&arP
f/\!=sa:
(query, parameter); q4BXrEOw
} &+9 ;
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public PaginationSupport findPageByCriteria xvGYd,dlK
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(final DetachedCriteria detachedCriteria){ 88Pt"[{1
return findPageByCriteria hV3]1E21"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); g4W$MI
} k-$Acv(
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public PaginationSupport findPageByCriteria d`\SX(C
U$:^^Zt`B
(final DetachedCriteria detachedCriteria, finalint 01Jav~WR
>N3X/8KL%
startIndex){ $G=^cNB|JB
return findPageByCriteria C&O8fNB_
AArLNXzVW
(detachedCriteria, PaginationSupport.PAGESIZE, l&& i`
LP3#f{U
startIndex); >^8O :.
} a-5UG#o
at>_EiS
public PaginationSupport findPageByCriteria T*p7[}#
$.,PteYK
(final DetachedCriteria detachedCriteria, finalint j;$f[@0o
>iyNZ]."\
pageSize, ``xm##K
finalint startIndex){ YB*)&@yx
return(PaginationSupport) 5{H)r
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getHibernateTemplate().execute(new HibernateCallback(){ +:A `e+\
publicObject doInHibernate 6Dd>ex!-A
<XL%*
(Session session)throws HibernateException { 6 `6I<OJ\
Criteria criteria = pbzt8 P[
{\Pk;M{Y&
detachedCriteria.getExecutableCriteria(session); Zf M]A)
int totalCount = e.\>GwM
2d[tcn$;h]
((Integer) criteria.setProjection(Projections.rowCount w+m7jn!$
%
:G78.
()).uniqueResult()).intValue(); ?M90K)&g{
criteria.setProjection +kI}O*s
6>?qBWW
(null); (4Db%Iw
List items = za>%hZf\
nS#F*)
criteria.setFirstResult(startIndex).setMaxResults oy[s])Tg
M:O*_>KF
(pageSize).list(); ]W3u~T*
PaginationSupport ps = HSud$(w
/{R
^J#
new PaginationSupport(items, totalCount, pageSize, DzC`yWstP
q~>!_q]FE
startIndex); .J.}}"+U
return ps; :7@[=n
} 8hV]t'/;
}, true); hn .(pI1
} *gmc6xY
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public List findAllByCriteria(final X&Oo[Z
u`EK^\R
DetachedCriteria detachedCriteria){ o.$48h(
return(List) getHibernateTemplate .p{lzI9
h`Jc%6o
().execute(new HibernateCallback(){ <mX5VGY9^
publicObject doInHibernate J
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Eq@sU?j
(Session session)throws HibernateException { hGFi|9/-u
Criteria criteria = <\*)YKjn/@
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detachedCriteria.getExecutableCriteria(session); W3l[a^1d
return criteria.list(); s=$xnc}mf
} $%U}k=-
}, true); hl[<o<`Q
} }51QUFhL0
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public int getCountByCriteria(final \,v^v]|
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DetachedCriteria detachedCriteria){ zGe =l;
Integer count = (Integer) Sh;`<Ggi~
%X\J%Fj
getHibernateTemplate().execute(new HibernateCallback(){ QM!UMqdj
publicObject doInHibernate hgZvti
wgDAb#Zuk
(Session session)throws HibernateException { WLWfe-
Criteria criteria = lf\"6VIsR
\;%D;3Au
detachedCriteria.getExecutableCriteria(session); =ZHN]PP
return yI=nu53BV
T7YJC,^m
criteria.setProjection(Projections.rowCount :Gz$(!j1.'
h-.^*=]R6
()).uniqueResult(); -/3h&g
} lBn<\Y!^
}, true); !B[Y?b:
return count.intValue(); e_Zs4\^ef
} <S_0=U
} [YQtX_;w
oCwep^P(v
;E}&{w/My
x~l"'qsK
e?\Od}Hbw
0"-H34M<D
用户在web层构造查询条件detachedCriteria,和可选的 D _\HX9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 AU*]D@H
daY0;,>
PaginationSupport的实例ps。 M|y!,/'
G>Bgw>#_
ps.getItems()得到已分页好的结果集 B'Nvl#
ps.getIndexes()得到分页索引的数组 FpttH?^
ps.getTotalCount()得到总结果数 6
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ps.getStartIndex()当前分页索引 h*4wi.-
ps.getNextIndex()下一页索引 "%
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ps.getPreviousIndex()上一页索引 ;8F6a:\v
<)cmI .J3
,:.8s>+i
c5CxR#O
7F~Jz*,B*W
vr>J$(F
WOYZ
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 |/-# N
AED
9vDE
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 D9(4%^HxV1
9(&$Gwi
一下代码重构了。 48gpXcc@|
z:n
JN%Qb
我把原本我的做法也提供出来供大家讨论吧: EZ Q!~
q9(O=7O]-
首先,为了实现分页查询,我封装了一个Page类: PVKq&Q?
java代码: 8=\k<X{`
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J(~xU0gd'
/*Created on 2005-4-14*/ ^[HX#JJ~
package org.flyware.util.page; |bRi bB
ZZL%5{w_
/** Y\H4.$V
* @author Joa 3,+UsB%
* 8BIPEY -I?
*/ Xp^>SSt:4
publicclass Page { B]D51R\}VE
>03JQe_#*L
/** imply if the page has previous page */ [xs`Pi
privateboolean hasPrePage; jaTCRn3|<
7")&njQ/x
/** imply if the page has next page */ H]lD*3b
privateboolean hasNextPage; a
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7
dG_E]&
/** the number of every page */ F,5}3$
privateint everyPage; yErvgf
'bef3P9`
/** the total page number */ .|ZnU]~T
privateint totalPage; v^IMN3^W
(+\K
/** the number of current page */ 4_eFc$^
privateint currentPage; =2wy;@f
x(zW<J5X"
/** the begin index of the records by the current 3'Z+PPd!
(i'wa6[E8
query */ J0Y-e39 `
privateint beginIndex; d#- <=6
%ye4FwkRy
:n?}G0y
/** The default constructor */ 6? (8KsaN
public Page(){ dZbG#4oO
)ULxB'Dm
} %hzNkyD)Y
?@_,_gTQ
/** construct the page by everyPage s&OwVQ<M
* @param everyPage rNHV
* */ |B*`%7{+
public Page(int everyPage){ CV,[x[L#{
this.everyPage = everyPage; qoD
M!~
} j[1^#kE
u`X}AKC
/** The whole constructor */ U#_rcu
public Page(boolean hasPrePage, boolean hasNextPage, -Kf'02
+%RXV~
`!T6#6h
int everyPage, int totalPage, 785Y*.p
int currentPage, int beginIndex){ )6zwprH!
this.hasPrePage = hasPrePage; HaamLu
this.hasNextPage = hasNextPage; 65A>p:OO
this.everyPage = everyPage; e.g$|C^$m
this.totalPage = totalPage; (3G]-
this.currentPage = currentPage; P(r}<SM
this.beginIndex = beginIndex; 80M4~'3
} KK*"s^L
>7V&pH'
/** M*c`@\
* @return sXSZ#@u,WN
* Returns the beginIndex. 1z(y>`ZBq
*/ >&9Iy"
publicint getBeginIndex(){ @{n2R3)k
B
return beginIndex; kR-5RaW
} BPKeG0F7
U`"nX)$
/** 86@@j*c(@k
* @param beginIndex )Nq$~aAm
* The beginIndex to set. yyHr. C
*/ 5B(r[Ni
b
publicvoid setBeginIndex(int beginIndex){ J`3pXc$.
this.beginIndex = beginIndex; 1k>*
} 71w$i
4
\h"QgHzp
/** Z5{M_^
* @return \*w*Q(&3
* Returns the currentPage. e~weYGK
*/ {/ _.]Vh
publicint getCurrentPage(){ $NWI_F4
return currentPage; r).S/
} Fx0<!_tY-
[OsW
/** >b/0i$8
* @param currentPage 2S8/
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* The currentPage to set. c>3W1"
*/ GRj{*zs
publicvoid setCurrentPage(int currentPage){ gGdZ}9
this.currentPage = currentPage; S*CRVs
} Kc\0-3 Z
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/** zn3i2MWS
* @return [w~1e)D
* Returns the everyPage. ?z60b=f8
*/ ^IM;D)X&:
publicint getEveryPage(){ I#f<YbzD
return everyPage; \Jv6Igu
} PHD$E s
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/** _Oq (&I
* @param everyPage g!%csf
* The everyPage to set. c66Iy"
*/ :/Nz' n
publicvoid setEveryPage(int everyPage){ ou-5iH?
this.everyPage = everyPage; GYv2^IB:
} !=0N38wA
x<=+RYz#^:
/** Xf9VW}`*8
* @return 8c3X9;a
* Returns the hasNextPage. 2Sb~tTGz79
*/ GI7CZ
publicboolean getHasNextPage(){ A HKS
[ N
return hasNextPage; B69 NL
} ]]%CO$`T[
fi#o>tVyJ
/** 4(YKwY2_L
* @param hasNextPage poHDA=#
3
* The hasNextPage to set. #,
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*/ D9c8#k9Y.
publicvoid setHasNextPage(boolean hasNextPage){ ">voi$Kzey
this.hasNextPage = hasNextPage; oc-7gz)
} hgKs[ySo,3
JCaT^KLz
/** "Rs^0iT7>
* @return K=Fcy#,f
* Returns the hasPrePage. !Nl"y'B|
*/ v?h#Ym3e<
publicboolean getHasPrePage(){ &2#x(v
return hasPrePage; K22W=B)Ln
} )kgy L,9
~&4,w9b)j
/** F=^vu7rf
* @param hasPrePage zYSXG-k
* The hasPrePage to set. haa[ob6T
*/ Vv=d*
publicvoid setHasPrePage(boolean hasPrePage){ ?~S\^4]
this.hasPrePage = hasPrePage; h.~S^uKi*
} F K={%
>&U]j*'4
/** kS?!"zk>
* @return Returns the totalPage. Pd^ilRB
* -\>Bphu,y
*/ ";",r^vr\
publicint getTotalPage(){ Fz)z&WT
return totalPage; ~"}-cl,
}
{v]A`u)
c+|,2e
0T
/** %qfEFhRC
* @param totalPage >48zRi\N
* The totalPage to set. R0\E?9P
*/ Yw+_( 2
9=
publicvoid setTotalPage(int totalPage){ {n%F^ky+7
this.totalPage = totalPage; Ql\{^s+
} t91v%L
Z10#6v
} pU`Q[HOs
v D}y%}
}L@!TWR-Qu
W/{HZ< :.
+l&ZN\@0X
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 WZ"x\K-;
r#3_F=xL5
个PageUtil,负责对Page对象进行构造: m]Z&
.,bA
java代码: ,n~H]66n
A*~zdZ p
&gcKv1a\
/*Created on 2005-4-14*/ i6(y Bn
package org.flyware.util.page; zj`!ZY?fv
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import org.apache.commons.logging.Log; )>$xbo")k
import org.apache.commons.logging.LogFactory; C8@SuJ
;9 XM
s)
/** i~.L{K
* @author Joa /[t]m,p$yq
* =QOtag1;
*/ oXV
publicclass PageUtil { eH=lX9
3MiNJi#=2
privatestaticfinal Log logger = LogFactory.getLog f#/v^Ql*
^B>
4:+^
(PageUtil.class); fkyj&M/
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/** j$A~3O<e"
* Use the origin page to create a new page =R?NOWrDY
* @param page 4 K{4=uU
* @param totalRecords *)U=ZO6S
* @return SG;]Vr
*/ Nm:nSqc
publicstatic Page createPage(Page page, int xAQ=oF
+
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totalRecords){ *w59BO&M4
return createPage(page.getEveryPage(), 0b~5i-zM/
Y*B}^!k6
page.getCurrentPage(), totalRecords); {Qg"1+hhM
} E,u@,= j
L5of(gQ5]
/** EM;]dLh
* the basic page utils not including exception u0#q)L8
z';p275
handler r^VH [c@c
* @param everyPage hf8=r5j=
* @param currentPage eB<R@a|?S
* @param totalRecords /) MzF6
* @return page =MRg
*/ W !2(Ph*
publicstatic Page createPage(int everyPage, int 9] Uvy|
Bj;Fy9[yb
currentPage, int totalRecords){ AnfJyltS
everyPage = getEveryPage(everyPage); $^y6>@~
currentPage = getCurrentPage(currentPage); Fla,#uB
int beginIndex = getBeginIndex(everyPage, %#yCp2
O:q 0-
currentPage); = %\;7
int totalPage = getTotalPage(everyPage,
o-_0
>QU1_'1r
totalRecords); 5L"{J5R}
boolean hasNextPage = hasNextPage(currentPage, g(>;Z@Y
2W~,,$
G
totalPage); /
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boolean hasPrePage = hasPrePage(currentPage); ;Pnz4Y4|eU
\NDSpT<Z
returnnew Page(hasPrePage, hasNextPage, 7y&Fb
everyPage, totalPage, |\*7J!Liv
currentPage, RN]4 Is:
tb/bEy^
beginIndex); 8AOJ'~$
} OTl\^!
$e_A( |
privatestaticint getEveryPage(int everyPage){ (SfP3
return everyPage == 0 ? 10 : everyPage; 12~zS
} wtndXhVC4>
8h78Zb&[
privatestaticint getCurrentPage(int currentPage){ ^EN_C<V;"d
return currentPage == 0 ? 1 : currentPage; %XMrSlSOp
} `
Cdk
b5
CY?]o4IV
privatestaticint getBeginIndex(int everyPage, int [kMXr'TyPX
c1'OIK C
currentPage){ <:W]u T
return(currentPage - 1) * everyPage; WhMr'l/e
} \RnGKQ"4
-:Nowb
privatestaticint getTotalPage(int everyPage, int iKu[j)F
hT>h
totalRecords){ 5-0
int totalPage = 0; Ge8&_7
/Tv=BXL-
if(totalRecords % everyPage == 0) uB>NwCL;
totalPage = totalRecords / everyPage; P)XkqOGpT9
else C=t:0.:PJ
totalPage = totalRecords / everyPage + 1 ; -P]J:7*0?\
xV:.)Dq9
return totalPage; G9<pYt{:
} tY C`?HT
- (VV
privatestaticboolean hasPrePage(int currentPage){ `Yn^ -W
return currentPage == 1 ? false : true; vHZw{'5y
} K8$Hg:Ky-/
@sO*O4os>
privatestaticboolean hasNextPage(int currentPage, KwlN
]0GOSh
int totalPage){ aEW
Z*y
return currentPage == totalPage || totalPage == 2[}^ zTtA
9TjAEeU
0 ? false : true; :+|b7fF
} &,4^LFZW
h6c8hp.
7]_UZ)u
} Sd2R$r
+*WE<4"!6
HWxk>F0
Ka1
F7b
C0[Rf.*
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 HU-4k/I~
;_R;P;<
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 jJg9M'@2!
sZ{Kl\1@
做法如下: 0NK]u~T<
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g+hz>^Wg
z%Ywjfn'
的信息,和一个结果集List: pv+FPB
java代码: J*F-tRuEw
S
U~vS
c|x:]W'ij
/*Created on 2005-6-13*/ _-H uO/
package com.adt.bo; BA' ($D>
[aU#"k)M
import java.util.List; 8XD9fB^
Z'6
o$Xv
import org.flyware.util.page.Page; >|KfO>
JAj<*TB.%
/** aSi:(w
* @author Joa xojy[c#
*/ 7=N=J<]pl
publicclass Result { ^QTl (L
ICo_O]
Ke
private Page page; ={ c=8G8T
XL_X0(AKf
private List content; "5BgajrB
9aD6mp
/** ZalG/PFy
* The default constructor .Ej `!
*/ }r3,
fH
public Result(){ ?d%+85
super(); KYD,eVQ
} L;I.6<K.
E,JDO d}
/** )fP,F(
* The constructor using fields 8X][TJG$
* V=I au_
* @param page B 9KY$^J
* @param content 5F+5J)h
*/ q]=.Aik
public Result(Page page, List content){ )5_GJm&R9
this.page = page; t*5d'aE`/
this.content = content; Na=9ju
} VG*BAFs
-v8Jn#f
/** (P~Jzp9u
* @return Returns the content. Gy.<gyK9
*/ k{Vc5F
publicList getContent(){ `0uKJFg
return content; z{bMW^F
} hi"[R@UG
{6^c3R[
/** qEX2K^y'4"
* @return Returns the page. m>k
j @^SQ
*/ l %=yT6
public Page getPage(){ Y}7'OM
return page; LN
]ks)
} ag]b]K
e]!Vxn3
/** %h=)>5-T
* @param content kXzm
* The content to set. g2L
*/
B]ul~FX
public void setContent(List content){ H"WkZX
this.content = content; fc._*y#AS
} #`RYKQwB
=xQ7:TB
/** fs&J%ku\
* @param page A9qCaq{
* The page to set. ,w; ~R4x
*/ VQU [5C
publicvoid setPage(Page page){ C6,GgDH`
this.page = page; p18-yt;
1
} D-9zg\\'`
} ?aEBS
'Y(#Yxc
gP/[=:
%E?:9. :NJ
yA?>v'K
2. 编写业务逻辑接口,并实现它(UserManager, ~QFD ^SoK
`J[(Dx'y=t
UserManagerImpl) bYQ h{q
java代码: V.)y7B
@;qC% +^
{S%)GvrT
/*Created on 2005-7-15*/ yT`[9u,
package com.adt.service; /%po@Pm#I
Wy@Z)z?
import net.sf.hibernate.HibernateException; bxyEn'vNvQ
tPP nW
import org.flyware.util.page.Page; $_k'!/5
t>7t4>X
import com.adt.bo.Result; "Ol;0>$
g-E!*K
/** }oYR.UH
* @author Joa N[^%|
*/ 9Re605xQ6
publicinterface UserManager { u><ax
6?Q&>V26Y
public Result listUser(Page page)throws FH)bE#4
RKdf1C
HibernateException; E"!9WF(2t5
?=jmyDXH!
} b5Rjn1@
$Rv}L' L
\hdR&f5q
o m`r^3,
P{)H7B>
java代码: *U.$=4Az
Y:&1;`FBZ
K6KEdXM4
/*Created on 2005-7-15*/ cCFSPT2fq[
package com.adt.service.impl; k^Tu9}[W1
<]/`#Xgh
import java.util.List; m}:";>?#
2n?\tOm(V
import net.sf.hibernate.HibernateException; &~pj)\_
IE$x2==)
import org.flyware.util.page.Page; 8V_
]}W
import org.flyware.util.page.PageUtil; fpM4q
U(-9xp+
import com.adt.bo.Result; daWmF
import com.adt.dao.UserDAO; |~8\{IcZ
import com.adt.exception.ObjectNotFoundException; '97)c7E
import com.adt.service.UserManager; LnZ*,>1Z
/4#.qq0\{c
/** F){f{-@)
* @author Joa j:"+/5rV8
*/ }!0,(<EsV
publicclass UserManagerImpl implements UserManager { nf,>l0,,'
yZHQql%J
O
private UserDAO userDAO; m(y?3}h
c[!e*n!y
/** 4v3y3
* @param userDAO The userDAO to set. (Ew o
*/ {5.,gb @6
publicvoid setUserDAO(UserDAO userDAO){ *`ehI_v :
this.userDAO = userDAO; V J){@
} &|%z!x6 f
d`StBXG!
/* (non-Javadoc) R"5/
* @see com.adt.service.UserManager#listUser ~ Cks)mJs
Z@
h<xo*r
(org.flyware.util.page.Page) ?@|1>epgd
*/ Qo DWR5*^D
public Result listUser(Page page)throws ^*A/92!yF
174H@
HibernateException, ObjectNotFoundException { fB1JU1
int totalRecords = userDAO.getUserCount(); miuJ!Kr'
if(totalRecords == 0) :KgLjhj|)
throw new ObjectNotFoundException AbZ:AJ(
X^_,`H@
("userNotExist"); 1k2Ck
page = PageUtil.createPage(page, totalRecords); bsM`C]h&
List users = userDAO.getUserByPage(page); Br]VCp
returnnew Result(page, users); X_HR$il
} hz Vpv,|G
:eQ@I+
} 3, ,Z
$7TYix8=
uP|AP
Vt
n$*ML
&BG^:4b
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ~#I1!y~`
~W5fJd0
询,接下来编写UserDAO的代码: IAnY+=^
3. UserDAO 和 UserDAOImpl: )K@ 20Q+0K
java代码: gD=s~DgN)
bT[Q:#GL
m
oFK/5cJ
/*Created on 2005-7-15*/ 5PKv@Mk
package com.adt.dao; =_%:9FnQ0
wIxLr{
import java.util.List; K_]LK
rM [Ps=5
import org.flyware.util.page.Page; *Ei~2O}
|YZ`CN<
import net.sf.hibernate.HibernateException; QV{Nq=%]
<FS/'[P
/** l:+tl/
* @author Joa .
Nog.
*/ d#ld*\|
publicinterface UserDAO extends BaseDAO { 8k_,Hni
y>~=o9J_u
publicList getUserByName(String name)throws SjlkKulMF
e6sL N
HibernateException; Mk@ _uPm
CG=#rc]vz
publicint getUserCount()throws HibernateException; ><\mt
]P(Eo|)m
publicList getUserByPage(Page page)throws 4LBjqv,P
vm8QKPy
HibernateException; >GT0x
hH"3Y}U@
} lG\lu'<C
J4`08,
5uDQ*nJ|
*>_:E6)
O(&EnNm[2
java代码: EHzU`('?[
zXcSE"
F{l,Tl"Jw
/*Created on 2005-7-15*/ ~p'/Z@Atu
package com.adt.dao.impl; 'QCvN b6
~JC``&6E=}
import java.util.List; yaR|d3ef?4
ik&loM_
import org.flyware.util.page.Page; ,Oxdqx u7
@Z3b^G[
import net.sf.hibernate.HibernateException; 6K`frt
import net.sf.hibernate.Query; "ajZ&{Z
7t@jj%F
import com.adt.dao.UserDAO; mXhr: e
E8%O+x}
/** _$cQAH0 E
* @author Joa ,j&o H$mW
*/ #7Qn\C2
public class UserDAOImpl extends BaseDAOHibernateImpl ]t(g7lc}U
/&kZ)XOi
implements UserDAO { (6 0,0|s
B Am{Gb
/* (non-Javadoc) !o*oT}6n
* @see com.adt.dao.UserDAO#getUserByName j:<E=[Kl
i]Kq
(java.lang.String) 1ed#nB%
*/ j1/J9F'
publicList getUserByName(String name)throws F!fxA#
HO' ELiZ_q
HibernateException { :dLS+cTC
String querySentence = "FROM user in class m{b(^K9}
uO"@YX/
com.adt.po.User WHERE user.name=:name"; i}HF
Query query = getSession().createQuery ?\c*DNM'
.@B\&U7
(querySentence); u;=("S{"0
query.setParameter("name", name); <#`<Ys3b*!
return query.list(); PicO3m
} UK_2i(I"e
6GJ?rE E/
/* (non-Javadoc) z#,?*v
* @see com.adt.dao.UserDAO#getUserCount() yGS._;#R
*/ T( ;BEyc?
publicint getUserCount()throws HibernateException { Oh8;YE-%
int count = 0; :U r%.0
String querySentence = "SELECT count(*) FROM (%I`EAR
s[xdID^3.
user in class com.adt.po.User"; Bb-x1{t
Query query = getSession().createQuery ,{E'k+
Xc
Pn
(querySentence); k)S7SbQ
count = ((Integer)query.iterate().next !3HMGzt
{{2ZWK 6|
()).intValue(); A`OU}'v?L
return count; Dhef|E<
} #}k^g:l1
*RuUf
/* (non-Javadoc) :=~([oSNW"
* @see com.adt.dao.UserDAO#getUserByPage r-'j#|^tz
{BKI8vy
(org.flyware.util.page.Page) :UScbPG
*/ >
]6Eb`v
publicList getUserByPage(Page page)throws JNMZn/
2OK%eVba
HibernateException { @8/-^Rh*
String querySentence = "FROM user in class 0|4XV{\qT$
66z1_lA
com.adt.po.User"; %PkJ7-/b|^
Query query = getSession().createQuery Rjh/M`|
t%8*$"~X
(querySentence); N'[^n,\(:
query.setFirstResult(page.getBeginIndex()) V$:v~*Y9
.setMaxResults(page.getEveryPage()); DoImWNLo
return query.list(); L#NPt4Sz+
} YpNTq_S1,
IClnh1=
} ri\r%x
{},GxrQm
E-!`6
6oJ~Jdn'
ZEApE+m
至此,一个完整的分页程序完成。前台的只需要调用 ?[VS0IBS
>TtkG|/U-T
userManager.listUser(page)即可得到一个Page对象和结果集对象 wt)tLMEv
m\jp$
的综合体,而传入的参数page对象则可以由前台传入,如果用 meIY00
L{\B9b2
webwork,甚至可以直接在配置文件中指定。 $=H\#e)]Ug
(<3'LhFII
下面给出一个webwork调用示例: e#16,a-}o
java代码: ~BZ A_w"`1
m3,]j\
}hl#
e[$
/*Created on 2005-6-17*/ !@*Ac$J>$
package com.adt.action.user; ]LP&v3
QF\NHV
import java.util.List; rGq~e|.O3
KeXQ'.x5O
import org.apache.commons.logging.Log; 0!!pNK%(
import org.apache.commons.logging.LogFactory; )8e_<^M
import org.flyware.util.page.Page; 8 Z#)Xb4
SJ+.i
u/
import com.adt.bo.Result; Fdvex$r&
import com.adt.service.UserService;
BH%eu 7`t
import com.opensymphony.xwork.Action; B23R9.FK
lm@<i4%$F
/** ^#"!uCq]gM
* @author Joa oOJN?97!k
*/ E#_}y}7JY
publicclass ListUser implementsAction{ zFv>'1$
2&5"m;<
privatestaticfinal Log logger = LogFactory.getLog "-^TA_XfI
L! Q&?xP
(ListUser.class); ZRcY; ?
}vcC4 =t/
private UserService userService; KZ<zsHX8H
+]*?J1Y8Z
private Page page; rEZa%)XJ
HM--`RJ
privateList users; $7PFos%@
a"hlPJlG
/* WO_cT26Y
* (non-Javadoc) &a-:ZA@
* 6)DYQ^4y
* @see com.opensymphony.xwork.Action#execute() c< \:lhl
*/ I_eYTy-a`1
publicString execute()throwsException{ b/ur!2yr
Result result = userService.listUser(page); Ku&0bXP
page = result.getPage(); 6C) G
users = result.getContent(); .cle^P
return SUCCESS; )LH nDx
} 3!ulBiMh
eK3J9;X
/** !XgkK k
* @return Returns the page. hv7!x=?8
*/ cH"M8gP#
public Page getPage(){ spn1Ji
return page; :9K5zD
} *gZ4Ub|O
o),i2
/** .$S`J2Y
* @return Returns the users. 0nA17^W
*/ hC5ivJ
publicList getUsers(){ P1H`NOC
return users; 1>l{c
} IXX^C}\,
H}JH339
/** Gl}=Q7
* @param page B||^sRMX
* The page to set.
:S?'6lOc(
*/ y]M/oH
publicvoid setPage(Page page){ E
jBEZL|_
this.page = page; mKWA-h+f
} g8}/Ln*W'
qFf'RgUtP
/** TZPWMCN4
* @param users v@"xEf1n[
* The users to set. 3]<$;[Q
*/ $5cLhi"`
publicvoid setUsers(List users){ Wc03Sv&FZ
this.users = users; 0>Ecm#
} <;SMczR
Alh%Z\
/** 3vmLftZE}
* @param userService $ShL^g@
* The userService to set. JTl
37j
*/ ,Ea.ts>
publicvoid setUserService(UserService userService){
0qZ{:}`3
this.userService = userService; t'0r4&\
} U}7$:hO"dX
} ma?569Z8~0
I+8m1*
QTK\"
>RE&>T^8
<k}>eGn
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, D
OPOzh
t`H^!
b
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 '_@=9 \<
5K{(V^88F
么只需要: (/Z~0hA[Q
java代码: g8!!:fdu
QBY7ZT05Gt
d*8 c,x
<?xml version="1.0"?> kn`KU.J.
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork H>-,1/IY
x\;`x$3t
1.0//EN" "http://www.opensymphony.com/xwork/xwork- d<(1^Rto
@wZ`;J %
1.0.dtd"> \f0I:%-
duV|'ntr
<xwork> ~>xn9vb=
7Dom[f
<package name="user" extends="webwork- C6CX{IA]
@QVAsNW:O
interceptors"> IS]0 3_uQ
>Mrz$
z{x
<!-- The default interceptor stack name m'oVqA&
Joq9.%7Q
--> 09%q/-$
<default-interceptor-ref dg/7?gV
(!DH'2I[
name="myDefaultWebStack"/> -:cS}I
fC]+C(*d
<action name="listUser" 6DR@$fpt
_(J- MCY\
class="com.adt.action.user.ListUser"> Pw
hs`YGMF
<param R 5bt~U
G-bG}9vc]
name="page.everyPage">10</param> ?2_u/x
<result 7:{4'Wr@6|
{3`#? q^o'
name="success">/user/user_list.jsp</result> U7tT
</action> w&`gx6?-na
q;tsA"l
</package> (fm\kV
xgsD<3
</xwork> bq<QUw=]q&
"p2 $R*ie
v#YO3nD
1}KNzMHk9
(3c,;koRR
_Vj O
[hx
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 :[|`&_D9J
^?&Jq_oU
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。 :]=Y1*L\)
)|uPCZdLZ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qJ#?=ITE
zu^?9k
?ti7iBz?
/M v\~vg$1
cJj0`@0f
我写的一个用于分页的类,用了泛型了,hoho 7+#^:;19`
</:f-J%U/
java代码: RyIr_:&-~
h_*=_ 2|}
N;Hrc6nin^
package com.intokr.util; @ g~kp
b(;"p-^
import java.util.List; $axaI$bE
REQ2pfk0
/** Ml+.\'r
* 用于分页的类<br> .y+>-[j?B
* 可以用于传递查询的结果也可以用于传送查询的参数<br> MvL%*("4b
* Q:>;d-D|1
* @version 0.01 zP
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* @author cheng JWlH(-U4|
*/ Ud`V"X
public class Paginator<E> { :4]&R9J>o
privateint count = 0; // 总记录数 g^}X3NUn
privateint p = 1; // 页编号 *z` {$hc
privateint num = 20; // 每页的记录数 .Z'CqBr[:
privateList<E> results = null; // 结果 6"-LGK:
-NiFO
/** A{y3yH`#h
* 结果总数 3vQ?vS|2
*/ hY-;Wfg
publicint getCount(){ |KplbU0iC
return count; TjgX' j
} cS4e}\q,
ogip#$A}3
publicvoid setCount(int count){ 08yTTt76t
this.count = count; j)'V_@
} IC92lPM }
_Dwn@{[(8
/** _+z@Qn?#6h
* 本结果所在的页码,从1开始 $J=9$.4"
* =
fuF]yL%
* @return Returns the pageNo. 7s<v06Wo
*/ f!xIMIl)+
publicint getP(){ 1PjSa4
return p; Ibd7[A\
} W{1=O)w
Fl(+c0|kT
/** W\N-~9UA
* if(p<=0) p=1 b0riiF
* Xb)XV$0
* @param p 84e)huAs
*/ ,XI,B\eNk
publicvoid setP(int p){ K&D
-1u
if(p <= 0) \P&'4y~PL
p = 1; EG7ki0
this.p = p; y 9/27yWB
} k-b_
<Tbo|
q<,?:g$k
/** Fr/8q:m&
* 每页记录数量 IDdhBdQ
*/ EOVHTDkKf
publicint getNum(){ YPf&y"E&H
return num; %D gU
} XH1so1h
eZI&d;i
/** }P-9\*hlm
* if(num<1) num=1 ,Y &Q,
*/ JQQD~J1)E
publicvoid setNum(int num){ qGl+KI
if(num < 1) vb5tyY0c
num = 1; `r+e!o
this.num = num; v|t^th,
} O`OntYwa>
u2 -%~Rlo
/** r,[vXxMy(;
* 获得总页数 '`/1?,=
*/ dH&N<
publicint getPageNum(){ ?!Rlp/
return(count - 1) / num + 1; k{y@&QNj
} .;/@k%>
5W 5\*L
/** ^0~?3t5
* 获得本页的开始编号,为 (p-1)*num+1 Zhz.8W
*/ 7! <cU
publicint getStart(){ Z-Bw?_e_K
return(p - 1) * num + 1; [AE]0cO@
} L7q%u.nB1
1i2jYDB"
/** jW?.>(
* @return Returns the results. t#6gjfIi
*/ N''9Bt+:
publicList<E> getResults(){ -;Cl0O%
return results; k+JDbJ@
} DE."XSni
M!!W>A@T[g
public void setResults(List<E> results){ y5|`B(
this.results = results; WvUe44&^$
} NrNbNFfo
.CQ
IN] iD
public String toString(){ 0qw,R4YK
StringBuilder buff = new StringBuilder N}>`Xm5'
/G G QO$'
(); Ur?a%]
buff.append("{"); VAsaJ`vcb
buff.append("count:").append(count); Y;xVB"
(
buff.append(",p:").append(p); $N+a4
buff.append(",nump:").append(num); Le|Ho^h,Y
buff.append(",results:").append .QRQvtd.
ran
Q_\
(results); l)a]V]oQ
buff.append("}"); $MB56]W8
return buff.toString(); t9Pu:B6
} ?J%$;"q
i/-Xpj]Zf
} 0)yvyQ5
nd'zO#"m?
Vyu 0OiGcR