Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ^Jtl;Q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 W"O-L
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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 yM17H\ =
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 `(T!>QVW+g
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。 YAMfP8S
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分页支持类: P' FKk<
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java代码: FG _,
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package com.javaeye.common.util; g
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import java.util.List; %(NN*o9"q
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publicclass PaginationSupport { UFk!dK+
pg5&=
publicfinalstaticint PAGESIZE = 30; O'Am
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privateint pageSize = PAGESIZE; KT%{G8Y@M
KE#$+,?
privateList items; QB9A-U<J
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privateint totalCount; |P~q/Wff
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privateint[] indexes = newint[0]; EFv4=OWB
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privateint startIndex = 0; L,%Z9
f:FpyCo=9
public PaginationSupport(List items, int 64b<0;~
ze$Y=<S
totalCount){ e9}8RHy1$
setPageSize(PAGESIZE); W%H]Uyt
setTotalCount(totalCount); iGQ n/Xdo
setItems(items); BWohMT
setStartIndex(0); {)uU6z
{'
} @oA0{&G{
,aYU$~o#
public PaginationSupport(List items, int 0ZT 0
6,3}/hgWJ$
totalCount, int startIndex){ ^K/G 5
setPageSize(PAGESIZE); ofl'G] /$+
setTotalCount(totalCount); <YSg~T
setItems(items); ,.q8Xf
setStartIndex(startIndex); [Q=4P*G}X
} m"q/,}DR
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public PaginationSupport(List items, int CCn/ udp@
lf;~5/%wMG
totalCount, int pageSize, int startIndex){ b<8q 92F
setPageSize(pageSize); >07shNX
setTotalCount(totalCount); CBIT`k.+
setItems(items); 9G+y.^/6
setStartIndex(startIndex); z=[l.Af_
} Slo9#26
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publicList getItems(){ 4^`PiRGt
return items; +{'lZa
} v/ eB,p
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publicvoid setItems(List items){ RpU Lm1b
this.items = items; 5W|u5AIw
} DYkC'+TEX
^b:Xo"q#H
publicint getPageSize(){ we
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return pageSize;
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} _J` |<}?t;
>
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publicvoid setPageSize(int pageSize){ #*+;B93)
this.pageSize = pageSize; gfxoJihE
} ]u~Os<
W.z$a.<(rF
publicint getTotalCount(){ fHLFeSfH
return totalCount; aQxe)
} A}gYcc85Z
AVU7WU{
publicvoid setTotalCount(int totalCount){ $m{{,&}k
if(totalCount > 0){ OX`?<@6
this.totalCount = totalCount; FzA{UO
int count = totalCount / bd.j,4^
Ls lM$
pageSize; .fbYB,0w
if(totalCount % pageSize > 0) l'W3=,G[?
count++; k:`a+LiZ
indexes = newint[count]; 8u/3?Kc
for(int i = 0; i < count; i++){ ]X/O IfdWe
indexes = pageSize * m\l51}xz
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i; 7xz#D4[
} H&w(]PDh
}else{ mf+K{y,L
this.totalCount = 0; +}&pVe\t
} t;h+Cf4
} m=#aHF
?`za-+<r<
publicint[] getIndexes(){ ZDW,7b%U
return indexes; )hePN4edj
} }<E sS
[5x+aW%ql
publicvoid setIndexes(int[] indexes){ ="/R5fp
this.indexes = indexes; P0a>+^:%
} "r:H5) !
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publicint getStartIndex(){ MacL3f
return startIndex; [O.LUR;
} MoZU(j
e|S+G6 :O2
publicvoid setStartIndex(int startIndex){ ": mCZUt
if(totalCount <= 0) ]kyle3#-~
this.startIndex = 0; pHq{S;R2G
elseif(startIndex >= totalCount) YhEiN. ~
this.startIndex = indexes =c
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>ly&+3S
[indexes.length - 1]; !a.3OpQ
elseif(startIndex < 0) W ]a7&S
this.startIndex = 0; FRb&@(;
else{ mMel,iK=
this.startIndex = indexes $_4oN(WSz
jI@bTS o
[startIndex / pageSize]; U/}AiCdj@
} Pc/.*kOT
} cP/F|uG5
MBnK&GS
publicint getNextIndex(){ [GcA.ABz
int nextIndex = getStartIndex() + de3yP,
3(oZZz
pageSize; ~nLkn#Z
if(nextIndex >= totalCount) T2c_vY
return getStartIndex(); KfJ c
else -MVNXAKnZ
return nextIndex; >FK)p
} p{\qSPK
yHa:?u6
publicint getPreviousIndex(){ wz*)L
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int previousIndex = getStartIndex() - iKR8^sj7S
+z~!#j4Q
pageSize; X3&SL~&>g
if(previousIndex < 0) fRca"v V
return0; O c^6u
else %fexuy4
return previousIndex; wN/*|?`Z
} ~ wJ3AqNC?
d()zW7}W
} =R"Eb1
S)Ub/`f{s
b |o`Q7Hj
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抽象业务类 %zIl_/s
java代码: &r5&6p
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/** SNopAACf1
* Created on 2005-7-12
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*/ wfU&{7yt
package com.javaeye.common.business; /ej/&x15
A*-]J=:E {
import java.io.Serializable; ILu0J`;}
import java.util.List; @8 oDy$j
{GG~E54&B
import org.hibernate.Criteria; 0C"PC:h5
import org.hibernate.HibernateException; 2Be ?5+
import org.hibernate.Session; <IHFD^3|j
import org.hibernate.criterion.DetachedCriteria; i+qLc6|S=2
import org.hibernate.criterion.Projections; GDNh?R
import <MWXew7b
~|0F?~eR7
org.springframework.orm.hibernate3.HibernateCallback; T9U2j-lA?
import E9Qd>o
D:RBq\8
org.springframework.orm.hibernate3.support.HibernateDaoS u+I r:k
/w}B07.
upport; !?us[f=g%
oZ\qT0*eb
import com.javaeye.common.util.PaginationSupport; kL2Zr
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public abstract class AbstractManager extends Jfixm=.6
}
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HibernateDaoSupport { \h'E5LO
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privateboolean cacheQueries = false; :DJ7d
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privateString queryCacheRegion; + 8K1]'t$
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publicvoid setCacheQueries(boolean I[cV"BDa
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cacheQueries){ iz%A0Z+`bg
this.cacheQueries = cacheQueries; Vm,f3~
} 3Q!J9t5dc
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publicvoid setQueryCacheRegion(String t}c}@i_c
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queryCacheRegion){ 7S~9E2N
this.queryCacheRegion = skC|io-Zv
;([tf;
queryCacheRegion; _:fO)gs|1
} D-b2E6o6
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publicvoid save(finalObject entity){ hB GGs
getHibernateTemplate().save(entity); *n|0\V<
} tci%=3,)
HC;I0&v>
publicvoid persist(finalObject entity){ kT }'"
getHibernateTemplate().save(entity); jhEg#Q$
} Jq+$_Uqd
h<^:Nn
publicvoid update(finalObject entity){ afP&+ 5t@O
getHibernateTemplate().update(entity); zcD_}t_K
} D@4&@>
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publicvoid delete(finalObject entity){ kvgs $
getHibernateTemplate().delete(entity); Y+_5"LV
} 7N59B z
dD.d?rnZq7
publicObject load(finalClass entity, 1J{z}yPHc
U)I `:J+A
finalSerializable id){ C +?@iMh
return getHibernateTemplate().load D8D!1 6_
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(entity, id); T
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} 3}#XA+Z
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publicObject get(finalClass entity, ;iC'{S
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finalSerializable id){ (P>eWw\0
return getHibernateTemplate().get o"ah\"#el
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(entity, id); #G ,
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} Pdm6u73
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publicList findAll(finalClass entity){ `2(R}zUHN
return getHibernateTemplate().find("from D"] [&m
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" + entity.getName()); ZAM+4#@
} +S5_J&~
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publicList findByNamedQuery(finalString ]20"la5
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namedQuery){ !{ESeBSCG
return getHibernateTemplate gy,TT<1)
Ualq>J5-m-
().findByNamedQuery(namedQuery); _hyxKrm'
6
} aEqI51I
n40MP5RxY
publicList findByNamedQuery(finalString query, k]/6/s\
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finalObject parameter){ <sCq
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return getHibernateTemplate !E:Vn *k;
,fG_'3wb
().findByNamedQuery(query, parameter); 4bFVyv
} v.2Vg
nM.?Q}yO~
publicList findByNamedQuery(finalString query, }B
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;7n*PBUJJ
finalObject[] parameters){ O"^a.`27
return getHibernateTemplate 'GzhZ`E6
6[|<
().findByNamedQuery(query, parameters); vwH7/+
} @oc%4~zl
NDa|.,
publicList find(finalString query){ 8~Hs3\Hp
return getHibernateTemplate().find Y7V&zF{
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(query); ^\kHEM|5v
} 4Z~Dxo
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publicList find(finalString query, finalObject U8$dG)PhA
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parameter){ iN4'jD^oP
return getHibernateTemplate().find ecZOX$'5
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(query, parameter);
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} dlzamoS@AR
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public PaginationSupport findPageByCriteria Hh;6B!zb+
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(final DetachedCriteria detachedCriteria){ _%Ld
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return findPageByCriteria J9=0?^v-:B
JIKxY$GS
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ZpctsCz]
} jL%}y1m?
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public PaginationSupport findPageByCriteria (4f9wrK
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(final DetachedCriteria detachedCriteria, finalint 7-IeJ6,D
|<
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startIndex){ "jc)N46
return findPageByCriteria LbbQ3$@WD
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(detachedCriteria, PaginationSupport.PAGESIZE, Dj.+5f'
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startIndex); []3}(8yxGb
} v!h-h&p O7
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public PaginationSupport findPageByCriteria |B$\3,
4^ 6L ])y
(final DetachedCriteria detachedCriteria, finalint KmOa^vY1.T
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pageSize, 'R'a/ZR`B7
finalint startIndex){ 9:w,@Phe
return(PaginationSupport) TC{Qu;`H+U
g2<S4
getHibernateTemplate().execute(new HibernateCallback(){ 3(*s|V"
publicObject doInHibernate X3O$Sd(D
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(Session session)throws HibernateException { $[CA#AXE
Criteria criteria = 5@%-=87S
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detachedCriteria.getExecutableCriteria(session); j:KQIwc
int totalCount = gK\7^95
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((Integer) criteria.setProjection(Projections.rowCount S)|b%mVwR
=T4w:
()).uniqueResult()).intValue(); s;WCz
criteria.setProjection ucP MT0k
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(null); (+ anTA=
List items = :Rj,'uH+h)
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criteria.setFirstResult(startIndex).setMaxResults aBi:S3 qk
.{Oq)^!ot
(pageSize).list(); 4H)"d
PaginationSupport ps = _N';`wjDY
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new PaginationSupport(items, totalCount, pageSize, t+J6P)=
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startIndex); rXPx*/C
return ps; VVl-cU
} P$Ru NF
}, true); ZUW>{'[K
} #'h CohL
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public List findAllByCriteria(final yLOLv6g~e
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DetachedCriteria detachedCriteria){ Kp8T;&<Iay
return(List) getHibernateTemplate s2=X>,kz?
S9oGf
().execute(new HibernateCallback(){ ]X|G+[Ujv
publicObject doInHibernate "]Td^Nxi
H H3
(Session session)throws HibernateException { >{Z=cv/6o
Criteria criteria = ZhaOH5{9
j!7Uj]
detachedCriteria.getExecutableCriteria(session); ;}'<`(f&nX
return criteria.list(); w/6@R 4)p
} hAyPaS #
}, true); lIP<`6=4
} IuW10}"9
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public int getCountByCriteria(final L]<4{8H.
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DetachedCriteria detachedCriteria){ {hR2NUm
Integer count = (Integer) lXKZNCL
#K w\r50
getHibernateTemplate().execute(new HibernateCallback(){ V7_??L%Ct`
publicObject doInHibernate <5~>.DuE
r^^C9"
(Session session)throws HibernateException { 1Di&vpn0u
Criteria criteria = uK5x[m
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detachedCriteria.getExecutableCriteria(session); F|Q#KwN
return .9Fm>e+!C
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criteria.setProjection(Projections.rowCount c iX2G
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()).uniqueResult(); 1hi j4m$b
} a"aV&t
}, true); l:f
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return count.intValue(); A,qG*lv
} Y&:i^k
} 5K{h)* *5
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>.\E'e5^C
pASVnXJZ
用户在web层构造查询条件detachedCriteria,和可选的 n\Ixv
S
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [=+/
^&HYnwk
PaginationSupport的实例ps。 (Ln h> '2
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ps.getItems()得到已分页好的结果集 .vMi<U;
ps.getIndexes()得到分页索引的数组 {8RGW0Y
ps.getTotalCount()得到总结果数 GNOC5 E$I
ps.getStartIndex()当前分页索引 O]lfs>>x
ps.getNextIndex()下一页索引 <@u6*]
ps.getPreviousIndex()上一页索引 >k|[U[@
mM.&c5U
9G~P)Z!0
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:^a$ve3(Jq
hgGcUpJy?
mGvP9E"&
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4>* `26
Vk-_H)*r
,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 $ 1U%E
@4$E.q<0
一下代码重构了。 +$5^+C\6A
_wCSL.
我把原本我的做法也提供出来供大家讨论吧: e$=|-Jz
J?'!8,RX
首先,为了实现分页查询,我封装了一个Page类: X)m2{@v D
java代码: cDg27xOUi
46~ug5gV
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/*Created on 2005-4-14*/
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package org.flyware.util.page; Gj 3/&'k6
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/** *OiHrI9y
* @author Joa 9"S3A EI
* '! (`?
*/ k
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publicclass Page { g 7X>i:
|:z%7J3wP
/** imply if the page has previous page */ Yo:&\a K[
privateboolean hasPrePage; tPsU7bFk
7|rT*-Ia
/** imply if the page has next page */ 1o%Hn"uG
privateboolean hasNextPage;
t2iFd?
=%LS9e^7D
/** the number of every page */ Gj=il-Po
privateint everyPage; Ry C7
bxs@_fH
/** the total page number */ STe;Sr&p
privateint totalPage; AI2CfH#:C
V 6F,X`7
/** the number of current page */ TL>e[PBO
privateint currentPage; M3%<kk-_
'mF}+v^
/** the begin index of the records by the current F <(Y
y+a&swd2(U
query */ B_>
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privateint beginIndex; \Z8!iruN
\B)<<[ $
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/** The default constructor */ iYnt:C
public Page(){ x>cu<,e$d\
k4v[2y`
} %:lQ ~yn
V6Y!0,w!a
/** construct the page by everyPage bGZy0.
* @param everyPage d9s"y?8
* */ _
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public Page(int everyPage){ tBrVg<]t
this.everyPage = everyPage; F~EriO
} k.%F!sK
m`Z4#_s2
/** The whole constructor */ R-ci?7d t3
public Page(boolean hasPrePage, boolean hasNextPage, /-T%yuU
lI9 3{!+>
5s;#C/ZZ
int everyPage, int totalPage, y}A-o_u@cD
int currentPage, int beginIndex){ Liofv4![
this.hasPrePage = hasPrePage; 945psG@|
this.hasNextPage = hasNextPage; i>;G4
this.everyPage = everyPage; #ed]zI9O
this.totalPage = totalPage; 9E5B.qlw$l
this.currentPage = currentPage; FE`J.aw^X
this.beginIndex = beginIndex; XZhhr1-<a
} %Xn)$Ti~<
N}\i!YUD
/** NJ.kT uk
* @return <T['J]k%
* Returns the beginIndex. q07>FW R
*/ ;RXv%ML
publicint getBeginIndex(){ ]Sh&8 #
return beginIndex; ][3 "xP
} ctf'/IZ5
!|D,cs
/**
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* @param beginIndex |$Td-M^)
* The beginIndex to set. CXa$QSu >
*/ ~/t#J
publicvoid setBeginIndex(int beginIndex){ 6 `'^$wKs
this.beginIndex = beginIndex; 61wiXX"N
} }+z}vb
fYwumx`J
/** pcE.
* @return gbvBgOp
* Returns the currentPage. t^q/'9Ai&J
*/ l1@:&j3h
publicint getCurrentPage(){ "YivjHa7H
return currentPage; K.z@Vx.
} %lujme
BzDS
/** T6tJwSS4:
* @param currentPage bcQ$S;U)
* The currentPage to set. U9Sp$$L
*/ {2!.3<#
publicvoid setCurrentPage(int currentPage){ (q)W<GYP
this.currentPage = currentPage; @ ~PL|Pp_
} Ba"Z^(:
t ,0~5>5
/** g%K3ah
v
* @return JWLQ9UX
* Returns the everyPage. lm$T`:c
*/ wDn5|F}i&
publicint getEveryPage(){ "F=O
return everyPage; _]B'C
} 'E9\V\bi
Q WOd&=:
/** G*ecM`Bl
* @param everyPage =T[kGg8`
* The everyPage to set.
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*/ @hk~8y]rz
publicvoid setEveryPage(int everyPage){ 6b@:La
this.everyPage = everyPage; !y6
D+<k*]
} Rt+s\MC^r
<=WQs2
/** q?`bu:yS
* @return 0 ~VniF^
* Returns the hasNextPage. dH8H<K~
*/ ^27r-0|l^
publicboolean getHasNextPage(){ m/<7FU8
return hasNextPage; `Dj-(~x
} @X|Cu bJ
y:xZ(RgfF
/** Iu=iC.50}
* @param hasNextPage <J\z6+,4E
* The hasNextPage to set. pbJs3uIR
*/ <Dl7|M
publicvoid setHasNextPage(boolean hasNextPage){ nT:ZSJWM
this.hasNextPage = hasNextPage; `C,47 9~J
} #5F\zeo@F?
$cnIsyKWY
/** 23zB@aE_?1
* @return k<m{Wp;-
* Returns the hasPrePage. ~h -0rE
*/ c'[l%4U8[
publicboolean getHasPrePage(){ 5MT$n4zKu
return hasPrePage; q45Hmz
} h60*=+vdJ
S_WYU&8
/** Mc9% s$MT
* @param hasPrePage c{zQX0
* The hasPrePage to set. >a[)F
*/ >osY?9
publicvoid setHasPrePage(boolean hasPrePage){ +[ !K
this.hasPrePage = hasPrePage; LyH{{+V
} u[})|x*N
2ACN5lyUS
/** L'.7V ~b{
* @return Returns the totalPage. I6~.sTl
* Iell`;
*/ K%O%#Kk
publicint getTotalPage(){ A?=g!( wB
return totalPage; Ng2qu!F7
} kU0e;r1 N
nKT\ /}d
/** l@%MS\{
* @param totalPage
a?_N8|k[
* The totalPage to set. 6|L<?
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*/ >2TDYB|;
publicvoid setTotalPage(int totalPage){ ^ 14U]<
this.totalPage = totalPage; ;~3CuN8
} 9ELLJ@oNC
82{Lx7pI
} ,dP-sD;<
xx_]e4
8i;EpAwB
E)7vuWOO
R_`i=>Z-
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 oSq4g{xvMH
)l~:Puvh
个PageUtil,负责对Page对象进行构造: "8>T
java代码: kZfa8wL]P
A}W)La\
!RN(/ &%y
/*Created on 2005-4-14*/ ]yy10Pk[!
package org.flyware.util.page; INZsDM 9
A\X?Aq-^'
import org.apache.commons.logging.Log; :XqqhG
import org.apache.commons.logging.LogFactory; W1fEUVj
@@M
2s(
/** 2r4owB?
* @author Joa h\k@7wgu
* c 2t<WRG
*/ @9Rgg9r
publicclass PageUtil { R7pdwKD
`fYICp
privatestaticfinal Log logger = LogFactory.getLog ?RNm8,M
&NM.}f
(PageUtil.class); DryN}EMOKD
MEf`&<t
/** M{w[hV
* Use the origin page to create a new page `lygJI?H+{
* @param page a\;Vly;
* @param totalRecords GgwO>[T
* @return Sc#B-4m
*/ kK\G+{z?
publicstatic Page createPage(Page page, int N8S!&*m
9.)*z-f$
totalRecords){ Z]OXitt7
return createPage(page.getEveryPage(), LX;w~fRr.
5n{J}0C
page.getCurrentPage(), totalRecords); 3D|Y4OM
} BWRAz*V
:Yeo*v9
/** RvrZtg5
* the basic page utils not including exception HtY0=r
)lh48Ag0t;
handler iYJ: P
* @param everyPage Vz_ac
vfk^
* @param currentPage b|jdYJbol&
* @param totalRecords qRi;[`
* @return page jd ]$U_U(
*/ J'{69<`Dl
publicstatic Page createPage(int everyPage, int |[qq
$
@/jLN
currentPage, int totalRecords){ nIc:<w]
everyPage = getEveryPage(everyPage); X)6}<A
currentPage = getCurrentPage(currentPage); '9d<vWg
int beginIndex = getBeginIndex(everyPage, }(tuBJ9
nwSujD
currentPage); $$'a
int totalPage = getTotalPage(everyPage, nz_=]PHO&
TNun)0p
totalRecords); +pMa-{
boolean hasNextPage = hasNextPage(currentPage, Zfwhg4G~
k+qxx5{
totalPage); F9h'.{@d
boolean hasPrePage = hasPrePage(currentPage); J5Pi"U$FkY
1V?)T
returnnew Page(hasPrePage, hasNextPage, q+<<Ku(20
everyPage, totalPage, n/]w!
currentPage, y-C=_v_X
*S _[8L"
beginIndex); }MU}-6
} B:5N Ia
{p.D E
privatestaticint getEveryPage(int everyPage){ 3QM; K^$
return everyPage == 0 ? 10 : everyPage; w2 %u;D%
} fyHFfPEE
}enS'Fpf`
privatestaticint getCurrentPage(int currentPage){ R;yi58Be
return currentPage == 0 ? 1 : currentPage; d OG]Yjc
} pX 4:WV
,EsPm'`?A/
privatestaticint getBeginIndex(int everyPage, int b{+7sl
M( euwy
currentPage){ HgVPyo
return(currentPage - 1) * everyPage; 4DLp+6zP
} VKGH+j[
HV0! G-h
privatestaticint getTotalPage(int everyPage, int &>%R)?SZh
nrFuhW\r
totalRecords){ vH[G#A~4
int totalPage = 0; s}1S6*Cr
[B0]%!hFw
if(totalRecords % everyPage == 0) mE>v (JY
totalPage = totalRecords / everyPage; >{/As][
else cpY'::5.%
totalPage = totalRecords / everyPage + 1 ; 0XgJCvMcB
+O]jklS4H
return totalPage; UYw_k\
} *HC[LM
3P}^Wu
privatestaticboolean hasPrePage(int currentPage){ N*mm[F2+F
return currentPage == 1 ? false : true; O4c[,Uq8~
} 85{2TXQ^%=
Nd;)V
privatestaticboolean hasNextPage(int currentPage, lhk=yVG3
E\$7tXQK6
int totalPage){ ox|K2A
return currentPage == totalPage || totalPage == `S)*(s?T
=P}BAJ
0 ? false : true; n PAl8
} ?@@BIg-
EdC^L`::
Jm#mC
} }Cs.Hm0P
r}>q*yx:
b '9L}q2m
9e aqq
n "J+?~9
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。 %@q/OVnM
3QZ~t#,7ij
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 Q$`u=-h|
7>@g)%",
做法如下: u*h+c8|zI
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 U??T>
$ap6Vxjr
的信息,和一个结果集List: P&g.%8b~84
java代码: 0b3z(x!O
?7eD<|
;$FpxurX
/*Created on 2005-6-13*/ ?|$IZ9
package com.adt.bo; USDqh437
n[f<]4<
import java.util.List; {y\5 9
+`(,1L1
import org.flyware.util.page.Page; e/J|wM9Ak
/4xp?Lo:
/** 6@X j
* @author Joa CS\ E]f
*/ f8AgTw,K8
publicclass Result { VNggDKS~K
_?m%i]~o
private Page page; naaww
]A.tauSW
private List content; 3[ T<pAZ
15)y]N={^
/** }$wWX}@
* The default constructor [m+):q^
*/ N5%Cwl6i
public Result(){ ?E2$
super(); p2)563#RS
} I}!ErV
}iBFo\vU
/** 0^G5 zQlj
* The constructor using fields JsY|Fv
* VKtZyhK"h
* @param page O&vE 5%x
* @param content &40# _>W7
*/ 65g"$:0
public Result(Page page, List content){ &X`zk
this.page = page; 1{0 L~
this.content = content; !$1'q~sO
} mR|;}u;d
fvH4<c5x
/** NAnccB D!{
* @return Returns the content. @5tW*:s
*/ L3s1a -K
publicList getContent(){ UifuRmn
return content; O% }EpIP_
} %jc"s\
O
S%
/** n5e1ky*9w
* @return Returns the page. -rXo}I,VI
*/ ]@G$L,3
public Page getPage(){ 6{8dv9tK
return page; kE`V@F
} =e j'5m($3
K'tckJ#%
/** ^U@-Dp,k+
* @param content = 3("gScUj
* The content to set. NBaXfWh
*/ Ak=|wY{
public void setContent(List content){ yG~7Xo5
this.content = content; 6:$+"@ps
} ?K9zTas@
u
^}R]:n
/** .R! /?eN
* @param page L32 [IL|
* The page to set. g71|t7Q
*/ miv)R
publicvoid setPage(Page page){ WJJwhr
this.page = page; r@v_hc
} =T3O; i
} 2J0N]`|)
UL<*z!y
`k.Nphx~%
! {c"C
ckCb)r_
2. 编写业务逻辑接口,并实现它(UserManager, sY*iRq
.Km6
(U
UserManagerImpl) tIJ?caX5=
java代码: c*:H6(u
+GDT@,/
aH(B}wh{
/*Created on 2005-7-15*/ i<>zN^zn
package com.adt.service; U|!L{+F
C;BC@OE
import net.sf.hibernate.HibernateException; $EUlh^
[L4s.l_#
import org.flyware.util.page.Page; |WMP_sGn
g2t'u4>
import com.adt.bo.Result; hDAxX=FM
V3] Z~@
/** U)B^R
* @author Joa a-(OAzQ_
*/ HAOl&\)7"_
publicinterface UserManager { v==]v2-
2S#|[wq(
public Result listUser(Page page)throws $u-yw1FT
F `cuV
HibernateException; G;k#06
6B .x=
} [flx/E
;wF 0s
Q
xg)Wb#
J~,Ny_L
*~H\#N|x
java代码: p#DJow
,4`=gKn
IJz=SV
/*Created on 2005-7-15*/ }_[Bp
package com.adt.service.impl; [l%6wIP&{
//W7$DYEG
import java.util.List; 1GA$nFBVC
F9\T<
import net.sf.hibernate.HibernateException; m.0:R
,rZp(moj
import org.flyware.util.page.Page; "T+oXK\B
import org.flyware.util.page.PageUtil; )~CnDk}^R
jXCSD@?]K
import com.adt.bo.Result; {=)g?!zC
import com.adt.dao.UserDAO; :,]*~Nl
import com.adt.exception.ObjectNotFoundException; t=B>t S.hO
import com.adt.service.UserManager; }63Qh}_Y
QW[
gDc
/** U`w `Cr
* @author Joa 6^vseVx
*/ Yj-JB
publicclass UserManagerImpl implements UserManager { 5:W5@e{
`N.^+Mvx-
private UserDAO userDAO; I C?bqC+
$-Wn|w+h<a
/** (|kcSnF0
* @param userDAO The userDAO to set. ~n<U8cm O
*/ ~EJ+<[/
publicvoid setUserDAO(UserDAO userDAO){ We51s^(
this.userDAO = userDAO; qS.TVNZ
} 34e>R?J
E!_mXjlPc
/* (non-Javadoc) +T|M U
* @see com.adt.service.UserManager#listUser >3\($<YDZM
vC1D}=Fp
(org.flyware.util.page.Page) pY T^Ug
*/ C 7e
public Result listUser(Page page)throws |:jka
Rx\.x? &
HibernateException, ObjectNotFoundException { 7%x
3o#&
int totalRecords = userDAO.getUserCount(); ecg>_%.>
if(totalRecords == 0) k.MAX8
throw new ObjectNotFoundException MfJ8+3@K
~8#Ku,vEy
("userNotExist"); \f6@B:?y
page = PageUtil.createPage(page, totalRecords); _${//`ia=
List users = userDAO.getUserByPage(page); 6Uik>e7?
returnnew Result(page, users); 9f/RD?(1O
} H,Ik&{@j
%DqPRl.Gu
} n>|7 k3
k_$9cVA
JxlU=7cF
`~ ,
[->uDbt zL
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ZBX,4kxK7
A3jT;D9Y%
询,接下来编写UserDAO的代码: Y%"6
3. UserDAO 和 UserDAOImpl: <R%]9#re
java代码: Gs7#W:e7
wy)I6`v
V/; / &
/*Created on 2005-7-15*/ nGvWlx
package com.adt.dao; n@"h^-
/ZcqKC
import java.util.List; GLIe8T*ht
`tZ-8f
import org.flyware.util.page.Page; Ln2dD> {2
ag~4m5n*~
import net.sf.hibernate.HibernateException; L(Ffa(i
M:* ^k
/** 1`;,_>8
* @author Joa xbeVqP
*/ K/OE;;<IA
publicinterface UserDAO extends BaseDAO { FSp57W$
I,pI2
publicList getUserByName(String name)throws 8&0+Az"{O
[l9iWs'M
HibernateException; |x[zzx#
>-
:vqfWK6mv
publicint getUserCount()throws HibernateException; a/(IvOy#6
No1*~EQ
publicList getUserByPage(Page page)throws P<1ZpL
4kZ9]5#.
HibernateException; GdxMHnn=
2d`:lk%\
} !oDX+hd,%>
6N^sUc0s
_Coh11
8LH"j(H
+/L "A
java代码: jw^Pt~@
/61P`1y(J
DV,rh83.ip
/*Created on 2005-7-15*/ }E}b/ulg1
package com.adt.dao.impl; "gR W91
T
vXio /m
import java.util.List; D m|_;iO,
;g0p`wV
import org.flyware.util.page.Page; c|s*(WljY
"HuV'
import net.sf.hibernate.HibernateException; 0^27grU>
import net.sf.hibernate.Query; JpFfO<uO
cP4K9:k
import com.adt.dao.UserDAO; PhS`,I^Z
cvf@B_iN9
/** #..-!>lY
* @author Joa d]v4`nc
*/ ZW]Q|vPh4U
public class UserDAOImpl extends BaseDAOHibernateImpl I^5T9}>Q
LOD'iiH6
implements UserDAO { f-V8/
V
ifQ@
/* (non-Javadoc) BZXP%{njS
* @see com.adt.dao.UserDAO#getUserByName P&ig.Og*
m]1=o7
(java.lang.String) :uAW
*/ Qo4+=^(
publicList getUserByName(String name)throws :?Xd&u0){
=ZsM[wd
HibernateException { N@M(Iw
String querySentence = "FROM user in class /ry#q%?
a:PS}_.
com.adt.po.User WHERE user.name=:name"; x4PH-f-7
Query query = getSession().createQuery KPGX/l
0/8rYBV
(querySentence); iK*2 Z$`lw
query.setParameter("name", name); He)<S?X-6
return query.list(); Y *
#'Gh,
} Xwg|fr+p
58H [sM4>
/* (non-Javadoc) #?xhfSgr
* @see com.adt.dao.UserDAO#getUserCount()
;;zKHS
*/
uC3o@qGW<
publicint getUserCount()throws HibernateException { 6]i"lqb
int count = 0; C043h?x
String querySentence = "SELECT count(*) FROM >IW0YIQy,
Lm kv.XF
user in class com.adt.po.User"; {emO=@CP
Query query = getSession().createQuery q16RPqfT
XE_|H1&j
(querySentence); |kvom 4 T
count = ((Integer)query.iterate().next G?LPj*=$?
u,:GJU
()).intValue(); v535LwFW
return count; f>)k<-<yj
} Azx4+`!-
0`=#1u8
/* (non-Javadoc) $oO9N^6yF
* @see com.adt.dao.UserDAO#getUserByPage 6i/x"vl>
=J0X{Ovn4z
(org.flyware.util.page.Page) `A@{})+
*/ .6%-Il
publicList getUserByPage(Page page)throws 4@PH5z
Egv (n@1
HibernateException { +#gJ[Cc
String querySentence = "FROM user in class 5;+OpB
^Bw2y&nN
com.adt.po.User"; \|Pp%U [
Query query = getSession().createQuery #C1u~db
/dpEL9K
(querySentence); k%V#{t.
query.setFirstResult(page.getBeginIndex()) _tZT
.setMaxResults(page.getEveryPage()); x^kV;^ I
return query.list(); +Zu*9&Cx
} $LLkYOwI
c&.>SR')
} w66iLQ\@
DVxW2J
<rc? EV
OD!b*Iy|
NF <|3|
至此,一个完整的分页程序完成。前台的只需要调用 K1 M s
w-l:* EV8
userManager.listUser(page)即可得到一个Page对象和结果集对象 ec/1Z8}p
/t`s.!k
的综合体,而传入的参数page对象则可以由前台传入,如果用 g+oSbC
~=~|@K
webwork,甚至可以直接在配置文件中指定。 A+*M<W
y@"6Dt|
下面给出一个webwork调用示例: nZe2bai
java代码: p9k'.H^:_
~G.'pyW
5q<AMg
/*Created on 2005-6-17*/ %EA|2O.D
package com.adt.action.user; >[;+QVr;
6('2.^8
import java.util.List; coq7La[
F)'kN2
import org.apache.commons.logging.Log; iIFM 5CT
import org.apache.commons.logging.LogFactory; Q@gmtAp
import org.flyware.util.page.Page; Tg|0!0qD]F
7M*&^P\}es
import com.adt.bo.Result; pEf1[ zq
import com.adt.service.UserService; ]cvP !
import com.opensymphony.xwork.Action; WPT0=Hqp7
v7x%V%K
/** k@MAi*
* @author Joa C&Rv$<qc
*/ z+IBy+
publicclass ListUser implementsAction{ {%W'Zx
y/57 >.3
privatestaticfinal Log logger = LogFactory.getLog I;xrw?=\L
H&`0I$8m
(ListUser.class); LUSBRr8
yO\.dp
private UserService userService; yClX!OL
zvjp]yTx"
private Page page; ~>vv9-_
<4r3ZV;'
privateList users; o9I=zAGjy
SVKjhZK
/* ,gAa9
* (non-Javadoc) -JgN$Sf
* `5da
* @see com.opensymphony.xwork.Action#execute() 8NCu;s
*/ cQM_kV??!
publicString execute()throwsException{ (R^X3
Result result = userService.listUser(page); (lPiv+'n
page = result.getPage(); .d
mUh-
users = result.getContent(); t!^ j0 q
return SUCCESS; ;1x(~pD*o
} cV8Bl="gqe
zsM3
[2E*
/** g"b{M
* @return Returns the page. $W} YXLFj?
*/ r xlKoa
public Page getPage(){ 3i\<#{
return page; mO#62e4C
} ,%Go.3i[
^:hI bF4G
/** `IC2}IiF
* @return Returns the users. .|?UqZ(,
*/ `2
6t+Tb
publicList getUsers(){ /7[U J'
return users; T~D2rt\
} rl/]Ym4j
I
\Luw*:
/** A!GQ4.~%
* @param page ^uCZO
* The page to set. f3;.+hJ])
*/ q0sdL86
publicvoid setPage(Page page){ q0t}
this.page = page; h85kQ^%
} ,#V}qSKUS
&=>|? m8
/**
b
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* @param users zm~sq_=^
* The users to set. F-TDS<[S?
*/ 'nQQqx%v
publicvoid setUsers(List users){ fUKi@*^ZUa
this.users = users; Rlwewxmr
} ;${_eab]
!,Uzt1K:
/** `z1E]{A
* @param userService YQ$Wif:@(n
* The userService to set. U32&"&";c
*/ &P:2`\'
publicvoid setUserService(UserService userService){ =6O<1<[y
this.userService = userService; ZNUSHxA
} Y'U]!c9
} -qs
R,H
=yCz!vc
aH'=k?Of;
h8
!(WO!
o |"iW" +
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, CFW#+U#U
[AN= G!r
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 phP%
S2PPwCU
么只需要: 'z$!9ufY,
java代码: bH`r=@.:cu
XY)I ~6$Y
Y+Cqc.JBQ
<?xml version="1.0"?> J`'wprSBb
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork shuoEeoo
B!AJ*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- La8 D%N
fqm-?vy}
1.0.dtd"> i~ITRi@
EHH+)mlo
<xwork> '9tV-whw
Lgrpy
<package name="user" extends="webwork- r 3FUddF'
@$R^-_m
interceptors"> jn._4TQ*}
U}c05GiQw
<!-- The default interceptor stack name 9D{p^hd
zOn%\
--> /|WBk}
<default-interceptor-ref Xu%8Q?]
z+{Q(8'b]
name="myDefaultWebStack"/> XGSgx
4YyVh.x
<action name="listUser" 3Bbd2[<W
UI_u:a9Q/
class="com.adt.action.user.ListUser"> .mvpFdn
<param 8fC5O
6g 5Lf) yG
name="page.everyPage">10</param> 4=C7V,a
<result !~-@p?kW/
4%>2>5
name="success">/user/user_list.jsp</result> v
O@7o
</action> KOit7+Q
b>'y[P!
</package> _qjkiKm?1F
n}3fItSJ
</xwork> y1t,i.
[
bq"dKN`
>slGicZ0
IP+.L]S
*DuP~8
(3QG
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 ';KZ.D
!Nx'4N`&l
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。 I`S?2i2H
N'=b8J-fF
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 R:,
|xz
t$(<9
QRz5eGpW
eK =v<X
JB9s#`
我写的一个用于分页的类,用了泛型了,hoho x]pZcx9
`c'R42SA
java代码: Qt"i
9k3RC}dEr
gi
JjE
package com.intokr.util; j7
\y1$w
>L,Pw1Y0W[
import java.util.List; VdF<#(X+
25/M2u?
/** ?;ovh nY)
* 用于分页的类<br> 4rH:`494
* 可以用于传递查询的结果也可以用于传送查询的参数<br> iE* Y@E5x0
* B<!WAw+
* @version 0.01 M:R|hR{=*
* @author cheng e<duDW$X
*/ r%vO^8FQ
public class Paginator<E> { qqr]S^WW
privateint count = 0; // 总记录数 gF~#M1!!
privateint p = 1; // 页编号 vhL/L?NB$
privateint num = 20; // 每页的记录数 7qEc9S@
privateList<E> results = null; // 结果 !xz{X ?
*s6(1S
/** K yDPD'
* 结果总数 #KwK``XC4
*/ #jT=;G7f2
publicint getCount(){ 3R`eddenF
return count; D |9ItxYu
} aJSBG|IC
ebIRXUF}>
publicvoid setCount(int count){ QRlrcauM
this.count = count; v|GDPq
} 7"s8G7
0%;y'd**Ck
/** lvk
r2Meu<
* 本结果所在的页码,从1开始 0`
UrB:
* TmUN@h
* @return Returns the pageNo. MRa
|<yK
*/ <XH,kI(%
publicint getP(){ <a)L5<#
return p; q*d@5
} OuwEO
>NAg*1
/** /4Jm]"
* if(p<=0) p=1 N2\{h(*u
* }o2e&.$4d
* @param p H@V+Q}
*/ T56%3i
publicvoid setP(int p){ G*W54[
if(p <= 0) 9s`j@B0N57
p = 1; `xie/
this.p = p; } .'\IR
} ?/FCq6o
g<jgR*TE`
/** O`D,> =[
* 每页记录数量 ]n^TN
r7
*/ T5? eb"
publicint getNum(){ k C=h[<'
return num; be+tAp`
} D5jZ;z}
o 12wp
/** aT20FEZ;
* if(num<1) num=1 l@<yC-Xd
*/ +WB';D
publicvoid setNum(int num){ Y^9b>H\2
if(num < 1) \Zmn!Gg
num = 1; }e4#Mx
this.num = num; DY?;Z98P?
} Q4QF_um
YLFM3IaP
/** [FN4 _
* 获得总页数 ;ep@
)Y
*/ wH0Ks5
publicint getPageNum(){ 6}^6+@LG
return(count - 1) / num + 1; uH=^ILN.
} ;SVAar4r
!1fAW!8
/** }8)iFP&"
* 获得本页的开始编号,为 (p-1)*num+1 +nm?+F
*/ ^>tqg^
publicint getStart(){ Xi"<'E3_
return(p - 1) * num + 1; z<z\)
} kbKGGn4u
$C`YVv%?0
/** Fa^I 1fk
* @return Returns the results. O YayTKxN
*/ _0
$W;8X
publicList<E> getResults(){ Ry4`Q$=:
return results; tk~<tqMq
} PYJ8\XZ1_N
U7le> d;L
public void setResults(List<E> results){ >TB Rp,;r
this.results = results; m8C
scCZ}
} ^:64(7
_MST8
public String toString(){ PR;A 0
StringBuilder buff = new StringBuilder )]P%=
Z
Vj
(); BIeeu@p
buff.append("{"); (5R_q.Wu
buff.append("count:").append(count); z2DjYTm[~
buff.append(",p:").append(p); _1U7@v:<@
buff.append(",nump:").append(num); ebmU~6v k
buff.append(",results:").append E!}~j
rIo)'L$uU
(results); {*Tnl-m~
buff.append("}"); C|H/x\?zRv
return buff.toString(); *7:HO{P>Y
} j/*4Wj[
Q=T/hb
} wTK>U`o
{((|IvP`
aFtL_#
U