Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `T&jPA9eY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 '{b1!nC;
DN] v_u+}
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 ~bK9R0|<
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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 9jir*UI
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。 EHf\L
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分页支持类: s>n(`?@L
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java代码: \wvg,j=
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package com.javaeye.common.util; \;X+X,M
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import java.util.List; ?Bi*1V<R
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publicclass PaginationSupport { f .
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publicfinalstaticint PAGESIZE = 30; eGL1
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privateint pageSize = PAGESIZE; b\7iY&.C|
W i.5Y{
privateList items; !U%T&?E l
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privateint totalCount; R"v 3!P
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privateint[] indexes = newint[0]; 1 T<+d5[C
da!P0x9p
privateint startIndex = 0; OHrY(I6
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public PaginationSupport(List items, int iSLGwTdLn
C G\tQbum
totalCount){ =<@2#E)
setPageSize(PAGESIZE); YUU-D(
setTotalCount(totalCount); ?tdd3ai>
setItems(items); #65^w=Sp}
setStartIndex(0); _n8GWBi
} EI~"L$?
+ECDD'^!
public PaginationSupport(List items, int %q;jVj[
R:-JkV>e:
totalCount, int startIndex){ 85:NFa@J
setPageSize(PAGESIZE); ,fDEz9-,
setTotalCount(totalCount); 8M,9kXq{L
setItems(items); `N//A}9
setStartIndex(startIndex); 'nQVj
} moj]j`P5a
WF&[HKOy/
public PaginationSupport(List items, int d,vNem-Z*L
54;J8XT7
totalCount, int pageSize, int startIndex){ hRI"y":zD
setPageSize(pageSize); ,21 np
setTotalCount(totalCount); LTV{{Z+
setItems(items); anw}w!@U
setStartIndex(startIndex); {CG_P,FO
} $mmup|;(
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publicList getItems(){ S d/?&
return items; <}U'V}g
} "vCM}F
+;g{$da5
publicvoid setItems(List items){ QVF]Ci_=
this.items = items; _zt19%Wg
} EV#MQM
RCTQhTy=
publicint getPageSize(){ jV#ahNq;
return pageSize; zf4Ec-)
} (Rk_-9_E.
\\BCcr\l
publicvoid setPageSize(int pageSize){ {e|*01hE
this.pageSize = pageSize; ONNpiK-
} $@d9<83=
ihh4pD27g
publicint getTotalCount(){ mNf8kwr
return totalCount; }pk#!N
} ^JI o?R
E ca\fkj
publicvoid setTotalCount(int totalCount){ 2 oa#0`{
if(totalCount > 0){ E^GHVt/.
this.totalCount = totalCount; /vY_Y3k#
int count = totalCount / a9n^WOJ6
48|s$K ^
pageSize; /&u<TJ4
if(totalCount % pageSize > 0) i{!T&8
count++; "dR|[a<#g
indexes = newint[count]; KZ!3j_pKy
for(int i = 0; i < count; i++){ K.G$]H
indexes = pageSize * Xi?b]Z
< B_Vc:Q
i; Qr1e@ =B
} S$f6a'
}else{ V`adWXu
this.totalCount = 0; \MxoZ
} st"{M\.p
} ^:9$@+a
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publicint[] getIndexes(){ V{|}}b?w?
return indexes; KXV[OF&J
} <Sz52Suh>
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publicvoid setIndexes(int[] indexes){ 0-LpqX
this.indexes = indexes; Q'k\8'x
} >5R<;#8
J 5h+s-'
publicint getStartIndex(){ +(uYwdcN
return startIndex; :'aAZegQY
} .(J?a"
{pb>$G:gfx
publicvoid setStartIndex(int startIndex){ 0l;<5
if(totalCount <= 0) H
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this.startIndex = 0; JT
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elseif(startIndex >= totalCount) A:<;M@q!
this.startIndex = indexes 9WJz~SP+vR
=)O,`.M.Y
[indexes.length - 1]; yL;M"L
elseif(startIndex < 0) Le"oAA#[
this.startIndex = 0; $+}+zZX5
else{ 8 6f2'o+
this.startIndex = indexes Tz2-Bp]h
qS&%!
[startIndex / pageSize]; $D31Q[p=+
} 1 nvTce
} nUq<TJ
p;?*}xa
publicint getNextIndex(){ S osj$9E
int nextIndex = getStartIndex() + h;5LgAY|v
^\B:R,
pageSize; 50dGBF
if(nextIndex >= totalCount) ?^:h\C^a"
return getStartIndex(); GRy-+#,b"
else iut`7
return nextIndex; /v095H@
} "^I
mb,
RFh"&0[
publicint getPreviousIndex(){ +!f=jg06
int previousIndex = getStartIndex() - &h*S
y
k%[3Q>5iM
pageSize; Y-ux7F{=z
if(previousIndex < 0) DoC(Z)o
return0; _md=Q$9!m
else 569}Xbc/
return previousIndex; 0iCPi)B
} Hn,:`mj4-6
6)pH|d.FR
} 2!N8rHRt
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抽象业务类 jQU"Ved
java代码: ~-a'v!
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/** HG/p$L*
* Created on 2005-7-12 f[gqT
yiP
*/ doHF|<s
package com.javaeye.common.business; v+6@cC
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import java.io.Serializable; h5
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import java.util.List; DjMf,wX-{
\EoX8b}$b0
import org.hibernate.Criteria; ^EVc 95|Z
import org.hibernate.HibernateException; ]j>i.5
import org.hibernate.Session; 59(U `X
import org.hibernate.criterion.DetachedCriteria; 9ykM3
import org.hibernate.criterion.Projections; Z?i /r5F
import '+<(;2Z
vL
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org.springframework.orm.hibernate3.HibernateCallback; Kr L>FI
import O?bK%P]ay
,]R8(bD)
org.springframework.orm.hibernate3.support.HibernateDaoS b7C
e%Br
K|W^l\Lt
upport; bM;`s5d
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import com.javaeye.common.util.PaginationSupport; JU0]Wq <^[
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public abstract class AbstractManager extends \d.F82
/I&wj^
HibernateDaoSupport { x:K?\<
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privateboolean cacheQueries = false; lp&!lb`
#;9H@:N
privateString queryCacheRegion; g+q@i{Yn
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publicvoid setCacheQueries(boolean Qqs"?Z,P
lpQP"%q
cacheQueries){ aP~gaSx
this.cacheQueries = cacheQueries; 74vmt<Q
} $,1dQeE
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publicvoid setQueryCacheRegion(String :jNYP{Br
g%J./F=@3
queryCacheRegion){ D\L!F6taS
this.queryCacheRegion = , j980/
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queryCacheRegion; F+=urc>w
} #0y<a:}R
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publicvoid save(finalObject entity){ 2PC5^Ni/9@
getHibernateTemplate().save(entity); ?A=b6Um
} i&ts YnP2
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publicvoid persist(finalObject entity){ g,lY ut
getHibernateTemplate().save(entity); XSD%t8<LO
} N)OCSeh
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publicvoid update(finalObject entity){ R8sck)k'}
getHibernateTemplate().update(entity); {Bs+G/?o/
} *re 44
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publicvoid delete(finalObject entity){ $4j^1U`~)K
getHibernateTemplate().delete(entity); v4<j
} 8]*Q79
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publicObject load(finalClass entity, |'w^ n
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finalSerializable id){ qzdaN5
return getHibernateTemplate().load Cg6;I.K
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(entity, id); +{>.Sk'$
} !A-;NGxE
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publicObject get(finalClass entity, 0VG=?dq
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finalSerializable id){ pI^=B-7
return getHibernateTemplate().get 02M7gBS
q!*MH/R
(entity, id); 4!'1/3cY
} )+B=z}:Nfz
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publicList findAll(finalClass entity){ s>J3\PC
return getHibernateTemplate().find("from .CmL7
5
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" + entity.getName()); ^Ezcy?
} <j"O%y.
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publicList findByNamedQuery(finalString TQ~&Y)".
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namedQuery){ =#'+"+lQ }
return getHibernateTemplate 8>v7v&Bh|
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().findByNamedQuery(namedQuery); |+mOH#Aty
} 'Aet{A=9
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publicList findByNamedQuery(finalString query, B{4"$Mi
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finalObject parameter){ jqqaw
return getHibernateTemplate 0O^r.&{j>
(V^QQ !:
().findByNamedQuery(query, parameter); @|]iSD&T
#
} S#hu2\9D,
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publicList findByNamedQuery(finalString query, k$?&]! <o
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finalObject[] parameters){ y,1S&k
return getHibernateTemplate D~7%};D[
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().findByNamedQuery(query, parameters); Do(PdF6A
} M Yu?&}%^
;7)OSGR
publicList find(finalString query){ yh4jRe?f
return getHibernateTemplate().find @!,D%]8"
AwA1&mh
(query); @gY'YA8m
} A>[hC{
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publicList find(finalString query, finalObject 37,L**Dgs
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parameter){ S/KVN(Z
return getHibernateTemplate().find hw7~i
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(query, parameter); 6j?FRs
} (cu'
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public PaginationSupport findPageByCriteria b"`ru~]
p3{x <AO/
(final DetachedCriteria detachedCriteria){ {/th`#o4b
return findPageByCriteria rwasH,+
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7AS.)Q#=x
} "m
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public PaginationSupport findPageByCriteria o",f(v&u%
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(final DetachedCriteria detachedCriteria, finalint ~% D^Ga7
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startIndex){ !hwzKm=%N
return findPageByCriteria c,+L +
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(detachedCriteria, PaginationSupport.PAGESIZE, \7OJN
~&<
V[BY/<z)A
startIndex); 6M
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} .rt8]%
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public PaginationSupport findPageByCriteria Z%, \+tRe
]
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(final DetachedCriteria detachedCriteria, finalint b#?ai3E
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pageSize, +0oyt?
finalint startIndex){ se^NQ=
return(PaginationSupport) 4?P%M"\Iv
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getHibernateTemplate().execute(new HibernateCallback(){ k;"R y8[k
publicObject doInHibernate kR`6s
Z`SWZ<
(Session session)throws HibernateException { F]URf&U
Criteria criteria = 2XETQ; 9
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detachedCriteria.getExecutableCriteria(session); m11"i=S"
int totalCount = xdFP$Y~ogy
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((Integer) criteria.setProjection(Projections.rowCount Z>>gXh<e[
Ti9:'I
()).uniqueResult()).intValue(); fY)4]= L
criteria.setProjection >Rl0%!
P ],)
(null); hB2s$QS
List items = Q%X:5G?
'NG^HLD/
criteria.setFirstResult(startIndex).setMaxResults 6\)8mK
jFJW3az@z
(pageSize).list(); xy-$v
PaginationSupport ps = wM2)KM}$
(d5vH)+A
new PaginationSupport(items, totalCount, pageSize, Z,N7nMJf
@Le ^- v4
startIndex); [+:mt</HN
return ps; ]sm0E@ 1
} ^cPo{xf
}, true); BW;=i.
} +aXk^+~j
YP
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public List findAllByCriteria(final t`Y1.]@U
NXWIE4T>*^
DetachedCriteria detachedCriteria){ f/IRO33
return(List) getHibernateTemplate 6>LQGO
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().execute(new HibernateCallback(){ &Gy'AUz-
publicObject doInHibernate vBCZ/F[
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(Session session)throws HibernateException { k?|zIu
Criteria criteria = )l[7;ZIw$
l;][Q]Z@V
detachedCriteria.getExecutableCriteria(session); qhn&;{{
return criteria.list(); qu#@F\gX
} F|n$0vQ*
}, true); [V #&sAe
} v&CO#vK5.
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public int getCountByCriteria(final 43orR !.Z
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DetachedCriteria detachedCriteria){ 6!Tf'#TV~!
Integer count = (Integer) ?+} E
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getHibernateTemplate().execute(new HibernateCallback(){ zx]M/=7,V#
publicObject doInHibernate te)g',#lT
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(Session session)throws HibernateException { Q&U= jX
Criteria criteria = x+)hL
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n
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detachedCriteria.getExecutableCriteria(session); -"JE-n
return n4d(`
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criteria.setProjection(Projections.rowCount <&m
r{:la56Xd
()).uniqueResult(); :#!F 7u
} XkfUPbU
}, true); o _,$`nEJ
return count.intValue(); zm^p7&ak$
} eEds-&_
} 'w$we6f
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用户在web层构造查询条件detachedCriteria,和可选的 ,4I6Rw B.
D
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <qj@waKw4
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PaginationSupport的实例ps。 Z"8cGN'
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ps.getItems()得到已分页好的结果集 HE.Dl7{
ps.getIndexes()得到分页索引的数组 24k}~"We
ps.getTotalCount()得到总结果数 e/~<\
ps.getStartIndex()当前分页索引 \nt'I;f
ps.getNextIndex()下一页索引 )n61IqrW
ps.getPreviousIndex()上一页索引 :EAfD(D{)
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V
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s0'U[]
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 C/#/F#C
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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 rMx_ <tX X
xpo}YF'5
一下代码重构了。 KWkT
9[H
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我把原本我的做法也提供出来供大家讨论吧: [IW7]Fv<F
U;Wmx
首先,为了实现分页查询,我封装了一个Page类: TMs\#
java代码: r F-yD1
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/*Created on 2005-4-14*/ *]k"H`JoFC
package org.flyware.util.page; 2^+"GCo
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/** tt91)^GdYa
* @author Joa 6ns_4,
e
* Ku# _
*/ Sy~Mh]{E
publicclass Page { my0->W%L
)FCqYCfk
/** imply if the page has previous page */
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privateboolean hasPrePage; /otgFQ_
1+#8} z:
/** imply if the page has next page */ 8hY)r~!b'
privateboolean hasNextPage; YEj U3^@
gA*zFhGVS7
/** the number of every page */ E{B<}n|}&
privateint everyPage; ' ga2C\)
C,rZ}-
/** the total page number */ YWdvL3Bgk,
privateint totalPage; +cN2 KP
2;tp>,G9d
/** the number of current page */ <k1gc,*
privateint currentPage; Wov_jVdN\
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/** the begin index of the records by the current l+,rc*-j0
IU}`5+:m
query */ vYkoh/(/u
privateint beginIndex; 04TV./uA
}"v"^5
j7zQ&ANF
/** The default constructor */ ,\b5M`<c
public Page(){ ho. a93
1+Oo Qs
} B'yrXa|P
e$Ej7_.#;
/** construct the page by everyPage L\5n!(,0
* @param everyPage l0f6L xfz
* */ Mtlj I6
public Page(int everyPage){ li?Gb1
this.everyPage = everyPage; S6uBk"V!
} 4T"P#)z
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/** The whole constructor */ @NZ?D0"
public Page(boolean hasPrePage, boolean hasNextPage, Cb<\
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int everyPage, int totalPage, LdL< 5Q[
int currentPage, int beginIndex){ sE% n=Ww
this.hasPrePage = hasPrePage; a[!':-R`s
this.hasNextPage = hasNextPage; rBaK$Ut
this.everyPage = everyPage; v?}/WKe+0
this.totalPage = totalPage; LYT0 XB)A
this.currentPage = currentPage; 0>vm&W<?)
this.beginIndex = beginIndex; ),86Y:^4
} iIg_S13
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/** 4&tY5m>
* @return Xo
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* Returns the beginIndex. fYpy5vc-dm
*/ umc!KOkL
publicint getBeginIndex(){ HG3jmI+u>
return beginIndex; v+Hu=RZE
} 0=~Ji_5mB
F$.M2*9
/** NWFZ:h@v
* @param beginIndex Mb-C DPT
* The beginIndex to set. 9K)2OX;$w
*/ f"/NY6
publicvoid setBeginIndex(int beginIndex){ Da.v yp
this.beginIndex = beginIndex; wEk9(|
} kIQMIL0+
dP )YPy_`
/** /Z-|E
* @return yQ\c<z^e
* Returns the currentPage. k9a-\UIMet
*/ +3VY0J
publicint getCurrentPage(){ 5<9}{X+@o
return currentPage; J-=&B5"O>
} wqJH
PM,I?lJ ,
/** "@.hz@>
* @param currentPage !s5 _JO
* The currentPage to set. .#CTL|x
*/ I~EJctOG
publicvoid setCurrentPage(int currentPage){ k |M
this.currentPage = currentPage; *r=6bpi
} r-=#C1eY&
&!_>J0
/** ge*f<#|0U-
* @return H&l/o
* Returns the everyPage. c.r]w
*/ / F9BbG{
publicint getEveryPage(){ 3(jI
return everyPage; ]v$VZ'
} |}=xA%)
R FWJ ZN"
/** w_PnEJa9
* @param everyPage /GqW1tcO
* The everyPage to set. ??)IPRv?yF
*/ 0.qnbDw_
publicvoid setEveryPage(int everyPage){ ]9F$/M#
this.everyPage = everyPage; 22(7rUkI
} ?31#:Mg6g+
a/^ojn
/** &( aw
* @return 67?O}~jbG
* Returns the hasNextPage. }I`"$2
*/ LB$#]
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publicboolean getHasNextPage(){ )lwxFP;
return hasNextPage; I82GZL
} f:bUM/Ud
Z^wogIAV
/** +XMKRt
* @param hasNextPage usc"m huQ
* The hasNextPage to set. ,%6!8vX
*/ %OE
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publicvoid setHasNextPage(boolean hasNextPage){ 3qggdi
this.hasNextPage = hasNextPage; Qa>t$`o`
} yGj'0c::
Pg4go10|
/** NpI "XQ
* @return ld
* Returns the hasPrePage. E &G]R!
*/ Bc&Y[u-n
publicboolean getHasPrePage(){ #l 7(WG
return hasPrePage; XN|[8+#U<@
} >W>3w
(_IP z)F
/** 0Sx$6:-~
* @param hasPrePage ;2N:
=Rv
* The hasPrePage to set. GBSuTu8
*/ *{<460`!q
publicvoid setHasPrePage(boolean hasPrePage){ nOTe 3?i>
this.hasPrePage = hasPrePage; 0(qtn9;=2
} 5LaF'>1yY
,B 2p\
/** Q{=DLm`
* @return Returns the totalPage. lq}m0}9<
* ~`yO@f;D
*/ Bi-x
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publicint getTotalPage(){ !:2_y'hA
return totalPage; ,,8'29yEq
} <5O:jd
bUU\bc
/** hm,H3pN
* @param totalPage TdeHs{|
* The totalPage to set. I+eKuWB
*/ dt5`UBvUg
publicvoid setTotalPage(int totalPage){ -[}Ah NYK
this.totalPage = totalPage; .k!<Oqa
} `|p8zV
s{uSU1lQn
} R!>l7p/|H)
W4#E&8g%
E>c*A40=.n
=xjtPmZ5X
9}T(m(WQVu
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 `3^%ft~l
(j&7`9<5
个PageUtil,负责对Page对象进行构造: m`&6[[)6~
java代码: ,l#f6H7p
)1/J5DI @8
[{PmU~RMYf
/*Created on 2005-4-14*/ >p29|TFbV
package org.flyware.util.page; 0zpA<"S
{!*dk
V
import org.apache.commons.logging.Log; 9w<k1j
import org.apache.commons.logging.LogFactory; o4H'
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/** eB_ M *+^
* @author Joa %'MR;hQsd8
* YR"IPyj
*/ b6^#{))"
publicclass PageUtil { r)gtx!bx
@4wN-T+1
privatestaticfinal Log logger = LogFactory.getLog ,-V7~gM%}
2NF#mWZ(s
(PageUtil.class); `aL4YH-v
8Yw V"+Fu/
/** /mQ9}E4X
* Use the origin page to create a new page e0g>.P@6
* @param page :@,UPc-+
* @param totalRecords S~ZRqL7ZO
* @return nm`}Z'&)
*/ y^:6D(SR
publicstatic Page createPage(Page page, int L{u1_
&!?qSi~V
totalRecords){ wV"C ,*V
return createPage(page.getEveryPage(), `cqZ;(^
(*G'~gSX
page.getCurrentPage(), totalRecords); H8$";T(I
} @l?2",
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/** sx][X itR+
* the basic page utils not including exception U/:x<Y$ tj
K@@Jt
handler 7J$Yd976
* @param everyPage 'p4b8:X
* @param currentPage C72btS
* @param totalRecords y:dwx *Q9I
* @return page (=w ff5U
*/ 7.(vog"I)
publicstatic Page createPage(int everyPage, int b*o,re)Dj
)q'~<QxI\
currentPage, int totalRecords){ l(?Yx
everyPage = getEveryPage(everyPage); 3bMUsyJ 2
currentPage = getCurrentPage(currentPage); ,E8~^\HV
int beginIndex = getBeginIndex(everyPage, %M;{+90p>t
ATf{;S}
currentPage); Gq^#.o]
int totalPage = getTotalPage(everyPage, ot.R Gpg%
+ywd(Tuzm
totalRecords); Y\ G^W8
boolean hasNextPage = hasNextPage(currentPage, \ /6m
!Mk:rO-L
totalPage); 7x:j4
boolean hasPrePage = hasPrePage(currentPage); IP+1 :M
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returnnew Page(hasPrePage, hasNextPage, >zWVM1\\j
everyPage, totalPage, _\2^s&iJh
currentPage, .
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!;YQQ<D
beginIndex); rCO:39L-
} 4C_-MJI
4 4kb
privatestaticint getEveryPage(int everyPage){ 7c Gq.U
return everyPage == 0 ? 10 : everyPage; ld*RL:G
} ^,KN@
wuTCdBu6hU
privatestaticint getCurrentPage(int currentPage){ rKys:is
return currentPage == 0 ? 1 : currentPage; 5-pz/%,
} `?L-{VtM3*
c~UYs\
privatestaticint getBeginIndex(int everyPage, int 84*Fal~Som
kV Z5>D$
currentPage){ _A.?:'-
return(currentPage - 1) * everyPage; weiqt
*,8
} l7r!fAV-f
tEl4 !vA
privatestaticint getTotalPage(int everyPage, int <WGl4#(k
L%.GKANM
totalRecords){ VNbq]L(g
int totalPage = 0; ?y{C"w!
HSOdqjR*
if(totalRecords % everyPage == 0) Th%1eLQ
totalPage = totalRecords / everyPage; {q:o}<-L+
else [y T4n.f
totalPage = totalRecords / everyPage + 1 ; .SdEhW15)
9c=_p'G3Fw
return totalPage; VBssn]w
} [@= [<
_r
$0Y&r]'
privatestaticboolean hasPrePage(int currentPage){ 2eu`X2IBcT
return currentPage == 1 ? false : true; K,}"v ;||
} 0\jOg
va8V{q@t'
privatestaticboolean hasNextPage(int currentPage, r Q'tab.,]
q$`:/ ehw
int totalPage){ ~&~%q u
return currentPage == totalPage || totalPage == `R^g[0 w'
WL}6YSC
0 ? false : true; #~.i\|VL
} 7-ba-[t#A
K.R2)o`
jl2nRo
} c`X'Q)c&K
n a2"Sy=Yi
&u"*vG (U[
[NvEXTd
J6 [x(T
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。 {7eKv+30
:<&}/r
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 dtM@iDljj
uU.9*B=H9
做法如下: 9$Mi/eLG2N
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~~zw[#'
<\^X,,WtO
的信息,和一个结果集List: e^Xij Id.
java代码: 31>k3IP&
-t6d`p;dR
k #*|-?
/*Created on 2005-6-13*/ pN0c'COy^
package com.adt.bo; @?B=8VHR
[k'Ph33c
import java.util.List; I9F[b#'Pn
FYcMvY
import org.flyware.util.page.Page; 6@XutciK
xk|$Oa
/** z{#F9'\&
* @author Joa U*&ZQw
*/ !W%HAlUAG[
publicclass Result { ^2kWD8c*
l IFt/
private Page page; OaCL'!
rIb[gm)Rk
private List content; uCu,'F,6Y
P/I{q s
/** .v" lY2:N
* The default constructor +rT(
*/ "}OFwes
public Result(){ Oq[E\8Wn
super(); s3+O=5
} ,K9UT#h
l#~FeD
/** @^` <iTK&p
* The constructor using fields !GIsmqVY
* kQ#eWk J,
* @param page i`>X5Da5
* @param content li%-9Jd
*/ 4]B3C\
v
public Result(Page page, List content){ uf;q/Wr
this.page = page; +uLo~GdbE
this.content = content; pt4xUu{
} okcl-q
@qC:% |>
/** %7d"()L
* @return Returns the content. _#gsR"FZ$
*/ -Y[-t;
publicList getContent(){ mN eW|3a
return content; 2T3DV])Q
} g\-3c=X
+zD'r5
/** lBn*G&(P
* @return Returns the page. bvgD;:Aj
*/ 'i(p@m<'
public Page getPage(){ # 0!IUSa
return page; u W|x)g11a
} YW{V4yW
{T.Vu]L80
/** h(8;7}K
* @param content -{*V)J_Co
* The content to set. VjqdKQeVq
*/ gk z#kiGF
public void setContent(List content){ u}1vn} F{
this.content = content; .O#lab`:2
} Mak9qaWqF>
>Y'yM4e*
/** GF!{SO4
* @param page #P-HV
* The page to set. W[>Tq T63
*/ sOxdq"E
publicvoid setPage(Page page){ j_yFH#^W:
this.page = page; <PN;D#2bh
} QiweM?-
} E
E|zY%
G
r|@CZq
Gr@{p"./z
_A|\.(t
C5 5n
2. 编写业务逻辑接口,并实现它(UserManager, ,A!e"=HF
5SL>q`t.bd
UserManagerImpl) &8AS=v
java代码: ba9<(0`
O|&TL9:
:J`!'{r
/*Created on 2005-7-15*/ r)5\3j[P
package com.adt.service; g**%J Xo
9H}iX0O
import net.sf.hibernate.HibernateException; `O=;E`ep
9T,QWk
import org.flyware.util.page.Page; ;vc lAsJ
8*#][wC2
import com.adt.bo.Result; 3d'ikkXK
.&Pe7`.BE
/** /^33 e+j
* @author Joa uP=_-ZUW
*/ N"x\YHp
publicinterface UserManager { +Q!xEfpO;
lZA>L,
\d
public Result listUser(Page page)throws mYjiiql~
txfwLqx
HibernateException; YeExjC
Xf_tj:eO~
} %c&Ah
PDq}Tq
ul=a\;3x#|
h,'mN\6t
KpbZnW}g
java代码: FP'u)eU&3
VVQ74b
@2~O^5[>
/*Created on 2005-7-15*/ t2-nCRXEP
package com.adt.service.impl; $|cp;~ 1
[%iUg\'7d
import java.util.List; _/]:=_bf_z
k|$"TFXx;
import net.sf.hibernate.HibernateException; zsMw5C
>.O*gv/_
import org.flyware.util.page.Page; b ?2X>QJ
import org.flyware.util.page.PageUtil; $XQ;~i
61+pryW%g
import com.adt.bo.Result; ny
import com.adt.dao.UserDAO; 'e<HP Ni)
import com.adt.exception.ObjectNotFoundException; & GzhcW~
import com.adt.service.UserManager; o3i,B),K
6h:?u4
/** V^Mf4!A(y
* @author Joa FU(}=5n
*/ A"BtVy[[9
publicclass UserManagerImpl implements UserManager { .e FOfV)
0x]OF8=J
private UserDAO userDAO; {+/
.5
]w_
/** FD
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* @param userDAO The userDAO to set. l6S19Kv
*/ a* W_fxb
publicvoid setUserDAO(UserDAO userDAO){ '!+P{
this.userDAO = userDAO;
rTP5-4
} co$Hi9JE
h+B'_`(
/* (non-Javadoc) cXOje"5i
* @see com.adt.service.UserManager#listUser G. -h=DT]
+3/k/W
(org.flyware.util.page.Page) 9zoT6QP4
*/ -'O Q-5
public Result listUser(Page page)throws j[m_qohd7
(c(-E|u.
HibernateException, ObjectNotFoundException {
JVUZ}#O
int totalRecords = userDAO.getUserCount(); RV0>-@/x
if(totalRecords == 0)
}@rg5$W
throw new ObjectNotFoundException 7d|*postv
,YP1$gj
("userNotExist"); '!j #X_;
page = PageUtil.createPage(page, totalRecords); 2~G,Ia
List users = userDAO.getUserByPage(page); d]O_E4X*
returnnew Result(page, users); u(V
} &Q-[;
@9}),hl`
} TIcd
_>TW
(R4PD
1A7 %0/K-]
Fb<n0[m
~q0I7M
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 pY+.SuM
Zdv.PGn
询,接下来编写UserDAO的代码: `ir&]jh.A
3. UserDAO 和 UserDAOImpl: -Z:]<;qU
java代码: CCbkxHMf|!
Zi 2o
5x*5|8
/*Created on 2005-7-15*/ Wmz q
package com.adt.dao; vOos*&
u~$WH, P3
import java.util.List; %v5)s(Yu
5h_<R!jA
import org.flyware.util.page.Page; ;;ER"N
*ZGX-+{
import net.sf.hibernate.HibernateException; VK @$JwdL
kP7a:(P_g
/** nqZA|-}
* @author Joa ~R :<Bw
*/ q>^hoW2$C
publicinterface UserDAO extends BaseDAO { 1*Sr5N[=
54<6Dy f
publicList getUserByName(String name)throws oS~}TR:}
q^Z~IZ8IT
HibernateException; K1:a]aU?Iu
%0vTA_W
publicint getUserCount()throws HibernateException; |r5e{
y)6,0K {k
publicList getUserByPage(Page page)throws ?3`q+[:
}ppVR$7]0
HibernateException; kGpV;F==*
RXBb:f
} rFhW^fP/
=g@R%NDNV
4py(R-8\
?8Et[tFg
jRofG'
java代码: #e*X0;m
\3r3{X
_<`
[!G)$<
/*Created on 2005-7-15*/ C*7!dW6
package com.adt.dao.impl; !(Q l)C
-PM)EGSk{
import java.util.List; R8tF/dx>7
qh-[L
import org.flyware.util.page.Page; VMx%1^/(
~wTX>qV
import net.sf.hibernate.HibernateException; Sr&T[ex,.
import net.sf.hibernate.Query; s|Zx(.EP
.!i0_Rv5x
import com.adt.dao.UserDAO; yLW/ -%I#u
]c}=5m/
/** " \:ced
* @author Joa PRD_!VOW
*/ +vz`go
public class UserDAOImpl extends BaseDAOHibernateImpl X/Y#U\
H>.B99vp
implements UserDAO { ]M3#3Ha"
`@|w>8bMz{
/* (non-Javadoc) Tw//!rpG
* @see com.adt.dao.UserDAO#getUserByName ~s#e,Kav"
&3Tx@XhO
(java.lang.String) k(vPg,X>m
*/ o'Pu'y
publicList getUserByName(String name)throws Jf)3< ~G
H0a-(
HibernateException { 4\p-TPM
String querySentence = "FROM user in class 2J<&rKCF
}E; F)=E
com.adt.po.User WHERE user.name=:name"; nLy#|C
Query query = getSession().createQuery ,)h)5o(?
Q2/.6O8
(querySentence); `5'2Hg+
query.setParameter("name", name); 1zjaR4Tf
return query.list(); KFDS q"j
} g_w&"=.jBq
i-W
/* (non-Javadoc) EvE,Dm?h
* @see com.adt.dao.UserDAO#getUserCount() aqMc6N`z
*/ r7 VXeoX
publicint getUserCount()throws HibernateException { S &JJIFftO
int count = 0; iePf ]O*
String querySentence = "SELECT count(*) FROM XoR>H4xh
~O;y?]U
user in class com.adt.po.User"; uLN[*D
Query query = getSession().createQuery j'GtgT
4:mCXP,x
(querySentence); E=u/tpj
count = ((Integer)query.iterate().next 7zDiHac
4_LQ?U>$
()).intValue(); S#8>ZwQ
return count; A+
0,i
} ],lV}Mlg*
N[Sb#w`[/
/* (non-Javadoc) IfV
3fJ7
* @see com.adt.dao.UserDAO#getUserByPage s_eOcm
ZA\/{Fw
(org.flyware.util.page.Page) EO)%UrWnC
*/ jm3G?Vnq
publicList getUserByPage(Page page)throws 2~c~{ jl\
NY.k.
HibernateException { #S5`Pd!I
String querySentence = "FROM user in class TJy4<rb
A0xC,V~z
com.adt.po.User"; Zk?
=
Query query = getSession().createQuery Ec]|p6a3
wW`}VKu
(querySentence); Vhg1/EgUr
query.setFirstResult(page.getBeginIndex()) Q\kub_I{@
.setMaxResults(page.getEveryPage()); ]hTb@.
return query.list(); YaY8 `M{
} =%qEf
G&9#*<F$c
} -_8*41
K7`YJp`i
E9 Y\X
gPEqjj
4]XI"-M^D
至此,一个完整的分页程序完成。前台的只需要调用 7#2j>G{?]v
j9y3hQ+q
userManager.listUser(page)即可得到一个Page对象和结果集对象 85 ]SC$
'Ud|Ex@A9
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~OFvu}]
'Bq ZOZw
webwork,甚至可以直接在配置文件中指定。 5EeDHsvV9
\2X$C#8E
下面给出一个webwork调用示例: 4$"DbaC
java代码: cFZCf8:zB
I6w~H?ul@*
8{I"q[GZ
/*Created on 2005-6-17*/ FGanxv@15
package com.adt.action.user; B~gV'(9g
t[C1z
import java.util.List; h)x_zZ%>o
[*Ju3
import org.apache.commons.logging.Log; _p}xZD\?,
import org.apache.commons.logging.LogFactory; TZB+lj1
import org.flyware.util.page.Page; <'m6^]:
Of7+/UV
import com.adt.bo.Result; 4A.Q21s
import com.adt.service.UserService; ;e s^R?z
import com.opensymphony.xwork.Action; OkH\^
G$JFuz)|
/** >1|g5
* @author Joa ;4~U,+Av
*/ .YcN S%
publicclass ListUser implementsAction{ FLr;`3
9%DT0.D}$j
privatestaticfinal Log logger = LogFactory.getLog Y& {|Sw7?
]qktj=p
(ListUser.class); Wk7WK` >i
Fvl`2W94;
private UserService userService; }STYG`
v.g"{us
private Page page; "^rNr_
2C
"=!'
privateList users; F:T GsV#
Faac]5u:*
/* +"!aM?o
* (non-Javadoc) !{%G0(Dv
* P:!)9/.2
* @see com.opensymphony.xwork.Action#execute() i$Z#9M9
*/ (xT*LF+
publicString execute()throwsException{ AXW!]=?X
Result result = userService.listUser(page); $k0H9_
page = result.getPage(); cf;Ht^M\
users = result.getContent(); GESXc$E8
return SUCCESS; La,QB3K/
} 2CLB1
kW-81
/** ?J&)W,~
* @return Returns the page. ^eh/HnJs
*/ AU{:;%.g
public Page getPage(){ K0fv( !r{
return page; v'ay.oVzw
} zhsx&
Spj9H ?m
/** P_Uutn~
* @return Returns the users. ($d4:Ww
*/ %e=!nRc
publicList getUsers(){ &3DK^|Lq
return users; d-$_|G+
} u{C)qb5Pu
*\ECf.7jz
/** VifmZ;S@Y
* @param page /lH'hcXcX
* The page to set. YoSQN/Z
*/ (F&YdWe:
publicvoid setPage(Page page){ GU6qIz|
this.page = page; p\D >z("
} F(4yS2h(
{;n0/
/** u,9q<&,
* @param users LDQ
e^
* The users to set. W~dE
*/ yT:!%\F9
publicvoid setUsers(List users){ yazZw}};
this.users = users; vLn> 4SK
} e,Zv]Cym
9d\N[[Vu]R
/** %b<%w
* @param userService ` d`&R.'
* The userService to set. EfSMFPM
*/ ^
f{qJ[,
publicvoid setUserService(UserService userService){ }x0Z(
`
this.userService = userService; @ ;J|xkJ
} X_?%A54z?
} m+T2vi
*k6$
RKk"
L>:FGNf^H
#pa\2d|
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, Y6;@ /[_
Ar5JP_M`E
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 H%T3Pc
8Mb$+^zU
么只需要: .~,^u
java代码: 8;.` {'r
h7RD`k:mF
SyB-iQn
<?xml version="1.0"?> b,vL8*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork c#x7N9;"!
[Ekgft&
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]>*I) H)
#VR`?n?,
1.0.dtd"> skSNzF7'
5W5pRd>Q
<xwork> cuNq9y;[
!g/_w
<package name="user" extends="webwork- MHn&;
A]
6d(b'S^
interceptors"> 4Xr"d@2(
t5A[o7BS
<!-- The default interceptor stack name *fOIq88
z22N7W=7
--> ;pCG9
<default-interceptor-ref +E `063
^
M8k
name="myDefaultWebStack"/> {AtfK>D
81cv:|"
<action name="listUser" Q!M sy<v
)/
n29]
class="com.adt.action.user.ListUser"> W *|OOa'
<param xQZMCd
0n7HkDo
name="page.everyPage">10</param> }$w4SpR
<result ~c9vdK
dcM+ylB
name="success">/user/user_list.jsp</result> e(4bx5<*
</action> 4bFv"b
upZYv~Sa
</package> Py}!C@e
~4}*Dhsh
</xwork> ~x9 W{B]
lS>=y#i3Xv
OME!W w
xu0;a
Y!Usce
%kaTQ"PB
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 q^Q|.&_k /
tP/GDC;
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。 qT&S
qYQUr8{
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 WXRHG)nvL
E5v|SFD
pQ 4
%]Api
(e>RNn\
*8pe<:A#p
我写的一个用于分页的类,用了泛型了,hoho 'Hcd&3a
ZA 99vO
java代码: &h_d|8
^F;Z%5P=
tF{{cd
package com.intokr.util; WW,r9D:/
B'P,?`
import java.util.List; /zDSlj<c
LRfFn^FPM
/** f@,hO5h(_|
* 用于分页的类<br> 1+.y,}F6b
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^ mQ;CMV
* =1uj1.h
* @version 0.01 }lrfO_
* @author cheng g&5pfrC [
*/ 1.ugXD
public class Paginator<E> { tZ*f~yW
privateint count = 0; // 总记录数 ?45K%;.9Q
privateint p = 1; // 页编号 b ?=
privateint num = 20; // 每页的记录数 '/]fZ|
privateList<E> results = null; // 结果 B 7x"ef
@EH4N%fH
/** Is#v6:#^
* 结果总数 iNaC ZC
*/ &].1[&M]
publicint getCount(){ XEe+&VQmY
return count; LRLhS<9
} B'[3kJ '
?\/dfK:!
publicvoid setCount(int count){ NnSI)*%'
this.count = count; /Va&k4
} VS@rM<K{
]#Z$jq{,
/** |Jx2"0:M
* 本结果所在的页码,从1开始 =kZwB*7
* 1.cUolnr
* @return Returns the pageNo. J*W;{Vty
*/ ~{]m8a/ `6
publicint getP(){ k)4lX|}Vm
return p; bNPjefBF
} 2
3XAkpzp$
tg%WVy2
/** &@.=)4Y
* if(p<=0) p=1 Ee?K|_\${
* }od7YL
* @param p V,*0<7h
*/ '-1jWw:8
publicvoid setP(int p){ aDJjVD
if(p <= 0) =S7C(;=4
p = 1; &>^Ympr
this.p = p; "%@=?X8
} i?s&\3--Y
o dQ&0d
/** H_nOE(i<z
* 每页记录数量 CIs1*:Q9
*/ +^3L~?
publicint getNum(){ z@S8H6jM)S
return num; kjYO0!C
} d'@H@
p]IhQnj2
/** 4lo}-@j
* if(num<1) num=1 #z54/T
*/ 5'L}LT8p@
publicvoid setNum(int num){ VDI S`E
if(num < 1) 0$dNrq
num = 1; VlXy&oZ
this.num = num; U~`^Y8UF
} ]KPg=@Q/
)k<~}wvQ0
/** aNf3 R; *
* 获得总页数 YyBq+6nq5
*/ MM)/B>c Qt
publicint getPageNum(){ 4Fc1'
return(count - 1) / num + 1; 9%'HB\A
} |N3CoB
gJfL$S'w
/** S{|)9EKw
* 获得本页的开始编号,为 (p-1)*num+1 OM C|.[
*/ -Ce4px?3
publicint getStart(){ &ZFAUE,[
return(p - 1) * num + 1; AS-t][m#
} 0'2{[xF
z:,!yU c
/** ?'_7#0R_0
* @return Returns the results. k EDZqUD
*/ <Q~7a
hF
publicList<E> getResults(){ t#{>y1[29
return results; Kt7x'5
} P`v~L;f
="eum7
public void setResults(List<E> results){ \} Szb2
this.results = results; h>Pg:*N,(
} ;|%JvptwW%
8-l Y6M\R\
public String toString(){ 6242qb
StringBuilder buff = new StringBuilder uk/+
i`=
6)YNjh.{*
(); /Day5\Q#
buff.append("{"); "x^bl+_"
buff.append("count:").append(count); 6-YR'ikU
buff.append(",p:").append(p); T+"y8#:
buff.append(",nump:").append(num); bj^m<}
buff.append(",results:").append 9m9=O&C~-<
ZEJadR
(results); 8dB~09Z7
buff.append("}"); QYGxr+D
return buff.toString(); PFw"ICs
} }w8AnaC
dG$0d_Pq
} MF(~!SOIG
/Q_\h+`
FI5C&d5d