Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 W?R6ZAn
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ,t?B+$E
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 \BTODZ:h
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 I<mV+ex
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分页支持类: '(f* 2eE:
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java代码: QUc= &5 %
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package com.javaeye.common.util; ^e _hLX\SW
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import java.util.List; qZtzO2Mt
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publicclass PaginationSupport { QvlObEhcS
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publicfinalstaticint PAGESIZE = 30; *SDs;kg
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privateint pageSize = PAGESIZE; Q:G4Z9Kt
+US!YU
privateList items; 3tIVXtUCUk
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privateint totalCount; _?m(V=z>
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privateint[] indexes = newint[0]; S]e|"n~@
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privateint startIndex = 0; "Y
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public PaginationSupport(List items, int GX!G>
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totalCount){ NqazpB*
setPageSize(PAGESIZE); *e TqVG.
setTotalCount(totalCount); N]Yd9tn{
setItems(items); #C74z$
setStartIndex(0); m<T%Rb4?@
} UJAv`yjG
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public PaginationSupport(List items, int Fx_z 6a
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totalCount, int startIndex){ p?%y82E
setPageSize(PAGESIZE); lHY+}v0
setTotalCount(totalCount); K,;E5
setItems(items); pSH=%u>
setStartIndex(startIndex); ;s = l52
} .GPT!lDc
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public PaginationSupport(List items, int E1aHKjLQ
r4b 6 c
totalCount, int pageSize, int startIndex){ T9E+\D
setPageSize(pageSize); (&Kk7<#`
setTotalCount(totalCount); bivuqKA
setItems(items); %ufN8w!p
setStartIndex(startIndex); #>("CAB02T
} %8 B}Cb&2c
ojm @t
publicList getItems(){ Fh&G;aEq
return items; \j}ZB<.>
} vFzRg5lH
`!3SF|x&
publicvoid setItems(List items){ $ZhFh{DQ.
this.items = items; >W=,j)MA
} S:#lH?<_
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publicint getPageSize(){ hlvK5Z
return pageSize; x}wG:K
} P-9)38`5
wv>^0\o
publicvoid setPageSize(int pageSize){ Gt8M&S-;
this.pageSize = pageSize; pGP7nw_g
} 8rAg\H3E
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publicint getTotalCount(){ P[G)sA_"
return totalCount; %OL$57Ia
} [NjXO`5#]
T8?Ghbn
publicvoid setTotalCount(int totalCount){ */5d>04
if(totalCount > 0){ 58}U^IW
this.totalCount = totalCount; :;%2BSgFU
int count = totalCount / y1jCg%'H
H*?t^
pageSize; >mbHy<<
if(totalCount % pageSize > 0) XAD- 'i
count++; nSDMOyj+
indexes = newint[count]; k>Is:P
for(int i = 0; i < count; i++){ $8)+XmsCr
indexes = pageSize * >4x(e\B
;>%r9pz ~
i; 9!ngy*\x
} \Gef \
}else{ k&M;,e3v6
this.totalCount = 0; h]5(].
} ;}I:\P
} WMDl=6
@Z_x.Y6
publicint[] getIndexes(){ aL\PGdgO
return indexes; 7(1|xYCx$
} etQCzYIhn
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publicvoid setIndexes(int[] indexes){ ~Py`P'+
this.indexes = indexes; IV~>I-rd
} R3f89
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publicint getStartIndex(){ $j%'{)gK
return startIndex; -u+vJ6EY
} 8L=HW G!1
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publicvoid setStartIndex(int startIndex){ @(w@e\Bq
if(totalCount <= 0) 1/B>XkCJ
this.startIndex = 0; n-2]M05O
elseif(startIndex >= totalCount) -vo})lO
this.startIndex = indexes oi7@s0@
4d4ZT?V[
[indexes.length - 1]; 5:[0z5Hww
elseif(startIndex < 0) -a}Dp~j
this.startIndex = 0; ZL&qp04}
else{ 20h}
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this.startIndex = indexes h%na>G
x3=A:}t8
[startIndex / pageSize]; /|m2WxK)
} _IHV7*u{;
} [o#oak{U
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publicint getNextIndex(){ un"Gozmt5
int nextIndex = getStartIndex() + i$"F{|Z0
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pageSize; PCee<W_%YE
if(nextIndex >= totalCount) |*eZD-f
return getStartIndex(); .[KrlfI
else 6dr%;Wp
return nextIndex; V*;(kEqj
} s-!ArB,
:as$4|
publicint getPreviousIndex(){ ~8Fk(E_
int previousIndex = getStartIndex() - |Pax =oJ\M
vkV0On
pageSize; ?3`UbN:
if(previousIndex < 0) 'W^YM@
return0; OX0%C.K)hZ
else dh iuI|?@
return previousIndex; :gibfk]C
} 9wUkh}s
SYJD?&C;
} YQvD|x
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抽象业务类 &-6Gc;f8
java代码: `wEb<H
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/** xwq
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* Created on 2005-7-12 nPl?K:(
*/ =z69e%.
package com.javaeye.common.business; BhGu!Y6f
&)ChQZA
import java.io.Serializable; D2eckLT
import java.util.List; s Y Qk
Qbn"=n2
import org.hibernate.Criteria; $k%2J9O
import org.hibernate.HibernateException; 'G4ICtHQ
import org.hibernate.Session; \'D0'\:vz
import org.hibernate.criterion.DetachedCriteria; *Kgks 4
import org.hibernate.criterion.Projections; HyZqUbHa
import WX?IYQ+
G 4X|Bka
org.springframework.orm.hibernate3.HibernateCallback; S`0(*A[W*
import -;m0R
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org.springframework.orm.hibernate3.support.HibernateDaoS zP8lN(LA
'Aq{UGN
upport; Yujiqi]J;
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import com.javaeye.common.util.PaginationSupport; IY\5@PVZ
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public abstract class AbstractManager extends ]MitOkX
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HibernateDaoSupport { X51:
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privateboolean cacheQueries = false; h2]P]@nW;W
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privateString queryCacheRegion; k2tF}
}@q`%uzi
publicvoid setCacheQueries(boolean G@X% +$I
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cacheQueries){ R"t,xM
this.cacheQueries = cacheQueries; ~-Qw.EdC
} ,m|h<faZL
{]@= ijjf
publicvoid setQueryCacheRegion(String /{n-Y/jp
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queryCacheRegion){ q{LF>Wi
this.queryCacheRegion = LCKV>3+_#
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queryCacheRegion; 4p;`C
} -zeG1gr3
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publicvoid save(finalObject entity){ p]+Pkxz]'
getHibernateTemplate().save(entity); []1C$.5DD
} `l[c_%Bm
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publicvoid persist(finalObject entity){ qqY"*uJ'
getHibernateTemplate().save(entity); N5
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} ul >3B4
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publicvoid update(finalObject entity){ K?1W!fY
getHibernateTemplate().update(entity); WP'!*[z
} xY(*.T9K
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publicvoid delete(finalObject entity){ =-n}[Y}A
getHibernateTemplate().delete(entity); JjTegQN
} 0 /U{p,r6`
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publicObject load(finalClass entity, I1M%J@ Cz
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finalSerializable id){ W[e$>yK
return getHibernateTemplate().load . 3T3EX|G
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(entity, id); +',S]Edx
} X\qNG]
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publicObject get(finalClass entity, k,+0u/I
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finalSerializable id){ yl+gL?IES
return getHibernateTemplate().get R$[vm6T?
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(entity, id); w%jII{@,
} ; )@~
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publicList findAll(finalClass entity){ VTY 5]|;
return getHibernateTemplate().find("from kJT)r6
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" + entity.getName()); Cjlk
} ;+hH
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publicList findByNamedQuery(finalString M&9+6e'-F
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namedQuery){ PIS2Ed]
return getHibernateTemplate F0Yd@Lk$_
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().findByNamedQuery(namedQuery); 3{sVVq5Y
} ^>v+(
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publicList findByNamedQuery(finalString query, pG;U2wE
w@w(-F!%l
finalObject parameter){ 7a<DKB
return getHibernateTemplate 4zFW-yy
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().findByNamedQuery(query, parameter); ,/|T-Ka
} A#YrWW
UH"%N)[
publicList findByNamedQuery(finalString query, iSs:oH3l
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finalObject[] parameters){ AFE~
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return getHibernateTemplate T</F
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' %o#q6O
().findByNamedQuery(query, parameters); <x>Mo
} ds[|
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publicList find(finalString query){ > /caXvS
return getHibernateTemplate().find }b.%Im<3R
j/?kL{B
(query); -m~#Bq
} ; kI134i=
L)
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publicList find(finalString query, finalObject St*h>V6
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parameter){ \(2sW^fY
return getHibernateTemplate().find 2`=7_v
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(query, parameter); "S?z@i(K^
} {F.[&/A
w ;^ra<*<+
public PaginationSupport findPageByCriteria t;\Y{`
<h *4Q
(final DetachedCriteria detachedCriteria){ gc$l^`+M
return findPageByCriteria @|YH|/RF
P@c5pc#|
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 9p(.A$
} %n9aaoD
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public PaginationSupport findPageByCriteria tK\~A,=
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(final DetachedCriteria detachedCriteria, finalint Lw>N rY(Y
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startIndex){ B^^#D0<
return findPageByCriteria {3aua:q
HN|%9{VeB
(detachedCriteria, PaginationSupport.PAGESIZE, )\$|X}uny&
<7jW_R@
startIndex); -nV9:opD
} P/_['7
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public PaginationSupport findPageByCriteria 1iF1GkLEq
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(final DetachedCriteria detachedCriteria, finalint /mzlH
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fn
pageSize, f) L
finalint startIndex){ b d!Y\OD
return(PaginationSupport) 'TB2:W3
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getHibernateTemplate().execute(new HibernateCallback(){ }k.Z~1y
publicObject doInHibernate j1T#yt
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(Session session)throws HibernateException { ' S/gmn
Criteria criteria = IJcsmNWm
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detachedCriteria.getExecutableCriteria(session); 4^o^F-k'
int totalCount = @f3E`8
|+D!=
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((Integer) criteria.setProjection(Projections.rowCount O?#7N[7
FGq[\B
()).uniqueResult()).intValue(); 5\VWC I
criteria.setProjection "E4a=YH_
S{T >}'y
(null); ~*];pV]A[
List items = )zDCu`
NC6&x=!3
criteria.setFirstResult(startIndex).setMaxResults O5BYD=7
1 [Bk%G@D&
(pageSize).list(); \1M4Dl5!
PaginationSupport ps = gL/9/b4
wi{3/
new PaginationSupport(items, totalCount, pageSize, Dk5 1z@
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startIndex); M x"\5i
return ps; {(Es(Sb}c
} }3WxZv]I}
}, true); 7D_=
} b4Ekqas
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public List findAllByCriteria(final +D*Z_Yh6
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DetachedCriteria detachedCriteria){ ]7c=PC
return(List) getHibernateTemplate -M#Wt`6A
+R75v )
().execute(new HibernateCallback(){ !C.4<?*|
publicObject doInHibernate {R{=+2K!|k
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(Session session)throws HibernateException { 9H1rO8k
Criteria criteria = gbD KE{
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detachedCriteria.getExecutableCriteria(session); gI|~|-'
return criteria.list(); %E;'ln4h&,
} 9%obq/Lb
}, true); Q22 GIr
} ba9?(+i$h
;}p
public int getCountByCriteria(final XQw9~$
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DetachedCriteria detachedCriteria){ G=bCNn<
Integer count = (Integer) bpa?C
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getHibernateTemplate().execute(new HibernateCallback(){ 1Ai^cf:S
publicObject doInHibernate >y+B
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(Session session)throws HibernateException { + LJ73
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Criteria criteria = |JsZJ9W+J
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detachedCriteria.getExecutableCriteria(session); )=(kBWM
return l;E(I_
i)
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criteria.setProjection(Projections.rowCount AQ^u
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()).uniqueResult(); tX~w{|k
} (**oRwr%
}, true); uHNCS zH(
return count.intValue(); 62NsJ<#>
} pTuS*MYz
} 2B`JGFcdcB
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43 :X,\~)
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用户在web层构造查询条件detachedCriteria,和可选的 A":T1s
/zox$p$?h
startIndex,调用业务bean的相应findByCriteria方法,返回一个 5`_SN74o
dgP3@`YS
PaginationSupport的实例ps。 J9 I:Q<;
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ps.getItems()得到已分页好的结果集 {\\Tgs
ps.getIndexes()得到分页索引的数组 #s9aI_
ps.getTotalCount()得到总结果数 x|29L7i
ps.getStartIndex()当前分页索引 bN=P*hdf
ps.getNextIndex()下一页索引 7x8
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ps.getPreviousIndex()上一页索引 K|s,ru
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 m)D|l1AtF
@[v~y"tE}
,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 H%lVl8oQ
W!(LF7_!
一下代码重构了。 q75s#[<ap
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我把原本我的做法也提供出来供大家讨论吧: Wn}'bqp
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首先,为了实现分页查询,我封装了一个Page类: ,v}k{( 16{
java代码: ?Ss!e$jf
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#
/*Created on 2005-4-14*/ 6-ils3&
package org.flyware.util.page; S0W||#Pr
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/** .5{ab\_af
* @author Joa 9-m=*|p
* W=4FFl[
*/ 1m0c|ckb
publicclass Page { @9|hMo
5Jnlz@P9
/** imply if the page has previous page */ 11;zNjD|
privateboolean hasPrePage; UkGCyGyZ[
q-d:TMkc
/** imply if the page has next page */ %e} Saf
privateboolean hasNextPage; `~q <N
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/** the number of every page */ C+&l<
fM&
privateint everyPage; 1[-tD0{H
El"Q'(:/U
/** the total page number */ n'6jou
privateint totalPage; b5n'=doR/I
cj5+NM"
/** the number of current page */ ,~W|]/b<q
privateint currentPage; ^sWT:BDh
Pg7Yp2)Oli
/** the begin index of the records by the current u\nh[1)a)
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query */ "g8M0[7e3
privateint beginIndex; '1/i"yoW
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/** The default constructor */ jWfa;&Ra
public Page(){ P7/X|M z
|P}y,pNQ
} m`r(p"
$* Kvc$D
/** construct the page by everyPage =odFmF
* @param everyPage 0:d_Yv,D
* */ uu687|Pm
public Page(int everyPage){ x-3\Ls[I
this.everyPage = everyPage; !g2+w$YVa
} #Mw8^FST
i~J'% a<Qp
/** The whole constructor */ f&
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public Page(boolean hasPrePage, boolean hasNextPage, ~&bq0(
cExS7~*
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int everyPage, int totalPage, |Xy6PN8
int currentPage, int beginIndex){ 0lR5<^B
this.hasPrePage = hasPrePage; J7p),[>I<
this.hasNextPage = hasNextPage; @;RXLq/8
this.everyPage = everyPage; c0u^zH<
this.totalPage = totalPage; }`~+]9<
this.currentPage = currentPage; wAW5
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this.beginIndex = beginIndex; =C.$
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} <UQbt N-B\
N?"]
/** n6a`;0f[R
* @return /I0%Z+`=
* Returns the beginIndex. Y0-n\|
*/ BF{Y"8u$
publicint getBeginIndex(){ s-T\r"d=j
return beginIndex; e**qF=HCw
} omBoo5e
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/** c\ l kD-\
* @param beginIndex WI-1)1t
* The beginIndex to set. y_lU=(%Jd
*/ SI-Ops~e
publicvoid setBeginIndex(int beginIndex){ OpYY{f
this.beginIndex = beginIndex; 9mTJ|sN:e
} 7O-x<P;
hx]?&zT@
/** @2 fg~2M1
* @return *CI#+P
* Returns the currentPage. ;@|n @ax
*/
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publicint getCurrentPage(){ N5b!.B x-w
return currentPage; W v+?TEP
}
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ckE-",G
/** Qn)a/w-
* @param currentPage YglmX"fLf
* The currentPage to set. Gu\q%'I
*/ l]l'4@1
publicvoid setCurrentPage(int currentPage){ .5ha}=z
this.currentPage = currentPage; q'Tf,a
} N64dO[op
i6Emhji
/** 8NAON5.!
* @return sN01rtB(UT
* Returns the everyPage. Vb]=B~ ^`
*/ l?n\i]'
publicint getEveryPage(){ [j/9neaye
return everyPage; UhQj
Qaa~
} ,M
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_5Ct]vy
/** K:#I
* @param everyPage _TQj~W<
* The everyPage to set. )W
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*/ h^(*Tv-!
publicvoid setEveryPage(int everyPage){ nazZ*lC
this.everyPage = everyPage; PmEsN&YP]
} <FkFs{(t
N]=q|D
/** C7ScS"~
* @return !9VY|&fHe
* Returns the hasNextPage. o~y;j75{.*
*/ YHygo#4=8
publicboolean getHasNextPage(){ uGK.\PB$
return hasNextPage; !@*7e:l
} E,x+JeKV
q\4Xs$APq
/** u.m[u)HQ
* @param hasNextPage oDA XiY$u
* The hasNextPage to set. H;k~oIsk
*/ LxSpctiNx
publicvoid setHasNextPage(boolean hasNextPage){ x,pjpx
this.hasNextPage = hasNextPage; fW1CFRHH
} J$w<$5UY
\aUC(K~o\;
/** _FU_Ubkr
* @return |a`Sc%
* Returns the hasPrePage. umH40rX+
*/
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publicboolean getHasPrePage(){ Em
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return hasPrePage; GdxnpE
} X Dm[Gc>(~
a;qryUyG
/** ND#Yenye
* @param hasPrePage n&qg;TT
* The hasPrePage to set. s %``H`
*/ 1N#|
}ad
publicvoid setHasPrePage(boolean hasPrePage){ G+"t/?/
this.hasPrePage = hasPrePage; g<;q.ZylT
} :tB1D@Cb6
{14fA)`%
/** {{D)YldtA
* @return Returns the totalPage. H.|#c^I
* y@: h4u"3
*/ 17[3/m8a
publicint getTotalPage(){
Rn(ec
return totalPage; M2>Vj/
} b"uu
.B]MpmpK
/** {JO
* @param totalPage ;!mzyb*
* The totalPage to set. FaQe_;
*/ HJLG=mU
publicvoid setTotalPage(int totalPage){ JPc+rfF
this.totalPage = totalPage; *yt=_Q
} Bs_s&a>
;4^Rx
} 9~5uaP$S
7Oa#c<2]
g1/[eoZzk
n.`($yR_
Vod\a5c
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 Pw7]r<Q
,.83m%i
个PageUtil,负责对Page对象进行构造: hk(ZM#Bh
java代码: x=hiQ>BIO0
8>2.UrC
0[NZ>7wqMZ
/*Created on 2005-4-14*/ 3LJ+v5T~
package org.flyware.util.page; */)c?)"
G~^r)fm_
import org.apache.commons.logging.Log; @; zl
import org.apache.commons.logging.LogFactory; \Xt7`I<
6y%qVx#!
/** L3u&/Tn2
* @author Joa 2\A$6N;_
* B4c]}r+
*/ q1$N>;&
publicclass PageUtil { t9k zw*U9
c@!_/0
privatestaticfinal Log logger = LogFactory.getLog 0U(@=7V
(Du@ S
(PageUtil.class); F 5bj=mI
u<7/0;D#+
/** knu,"<
* Use the origin page to create a new page 9-VNp;V
* @param page 'NXN& {
* @param totalRecords }WC[$Y_@
* @return b$d;Qx
*/ 7{e
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publicstatic Page createPage(Page page, int ExY] Sdx
zsEc(
totalRecords){ |B?m,U$A!
return createPage(page.getEveryPage(), Thp[+KP>
. oF
&Ff/[
page.getCurrentPage(), totalRecords); j78i#}e
} /wQy17g
O@T9x$
/** :;RMo2Tl
* the basic page utils not including exception #`qx<y*S
4M=]wR;
handler &&5aM
* @param everyPage |PvPAPy)uu
* @param currentPage !P2ro~0/
* @param totalRecords 4qb/daE:Z
* @return page L4@K~8j7
*/ J|W<;
publicstatic Page createPage(int everyPage, int }kw#7m54
9@SC}AF.
currentPage, int totalRecords){ WA<v9#m
everyPage = getEveryPage(everyPage); QGMV}y
currentPage = getCurrentPage(currentPage); ~dyTVJ$
int beginIndex = getBeginIndex(everyPage, b<tNk]7
h/QXPdV
currentPage); ^rB8? kt
int totalPage = getTotalPage(everyPage, Z\(q@3 C
{X!r8i
totalRecords); $f$SNx)),
boolean hasNextPage = hasNextPage(currentPage, z{%<<pZ
J@/kIrx
totalPage); E'f{i:O"~
boolean hasPrePage = hasPrePage(currentPage); WJ]T\DI
=ke2;}X
returnnew Page(hasPrePage, hasNextPage, U"~>jZKk
everyPage, totalPage, [CTnXb
currentPage, M:=J^0
H-!,yte
beginIndex); ]"pVj6O
} 1>.Ev,X+e
4V"E8rUL(
privatestaticint getEveryPage(int everyPage){ {Ea
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j
return everyPage == 0 ? 10 : everyPage; ,=uD^n:
} _kC-dEGf!y
nd`1m[7MNu
privatestaticint getCurrentPage(int currentPage){ L@rcK!s,lD
return currentPage == 0 ? 1 : currentPage; }t!Gey
} fQ7V/x!
Q*GN`07@?d
privatestaticint getBeginIndex(int everyPage, int x
o;QCOH
5f rX
currentPage){ B4ZBq%Z_
return(currentPage - 1) * everyPage; M.JA.I@XC
} .w:DFk^E]b
V_)-#=J
privatestaticint getTotalPage(int everyPage, int 1Te%F+7
MnmVl"(/
totalRecords){ "BAK !N$9
int totalPage = 0; "mo?*
a$Sk
_OYasJUMG
if(totalRecords % everyPage == 0) ?C]vS_jAh
totalPage = totalRecords / everyPage; 6]i-E>p3R
else OUE(I3_
totalPage = totalRecords / everyPage + 1 ; R-
X5K-
A]*}HZ,
return totalPage; @?ebuj5{e
} ~"gA,e-)
p;a,#IJu
privatestaticboolean hasPrePage(int currentPage){ *9
{PEx
return currentPage == 1 ? false : true; n>z9K')
} UJUEYG
4>YR{
privatestaticboolean hasNextPage(int currentPage, j\yjc/m
qyb?49I
int totalPage){ yHYsZ,GE
return currentPage == totalPage || totalPage == /|w6:;$;mn
/*~EO{o
0 ? false : true; hXw]K"
} kb%;=t2
Xc++b|k
NCXRevE
} 3=#<X-);
O *C;Vqt
h#I>M`|
Xxj-
6i
[>3./YH`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]2A^1Del
d2FswF$C
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 UsG~row:!
+bxYGD
做法如下: =>S]q71
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D_ 2:k'4
2y\E[j A
的信息,和一个结果集List: j a[Et/r
java代码: u~N?NW Q
Yu/ID!`Z
^S<Y>Nm]
/*Created on 2005-6-13*/ NSMyliM1Y
package com.adt.bo; @)+AaC#-
},?kk1vIT{
import java.util.List; uh_RGM&
,oe <
import org.flyware.util.page.Page; 3d8L6GJ
Eh`7X=Z7E
/** ?PxP% $hS
* @author Joa cU (D{~
*/ L<S9
publicclass Result { OdbEq?3S/?
P;y45b
private Page page; UXz<)RvB
T~?Ff|qFC
private List content; e
,'_xV
^#-l
q)
/** ~D+bh~
* The default constructor `RT>}_j
*/ YDsb3X<0'
public Result(){ mUC)gA/
super(); ^0)g/`H^>
} YMyfL8bO
KkyVSoD\
/** B
IEO,W|
* The constructor using fields pad*oPH,
* +^ac'Y)A
* @param page NYUL:Tp
* @param content "Y.tht H
*/ 2W(s(-hD
public Result(Page page, List content){ SR
hiQ
this.page = page; c]-<vkpV
this.content = content; 6wRd<]C
} #MkTkm&r
0o4XUW
/** Wb_J(!da
* @return Returns the content. wm@@$
*/ `hm-.@f,9
publicList getContent(){ rKc9b<Ir
return content; sdrfsrNvB-
} {?0lBfB"
>uB?rGcM
/** K3m/(jdO
* @return Returns the page. @bLy,Xr&
*/ xa*hi87L*
public Page getPage(){ I,DS@SK
return page; ^CH=O|8j
} <dNOd0e
T Z@]:e:"b
/** z6P$pqyF
* @param content zI uJ-8T"
* The content to set. Zl!kJ:0
*/ ~=LE0. 3[
public void setContent(List content){ On?v|10r'
this.content = content; >6-`}G+|
} 5;WH:XM
$wa{~'
/** YP<ms
* @param page a-tmq]]E
* The page to set. +=h:Vb8
*/ Ne!lH@ql
publicvoid setPage(Page page){ ,qwuLBW
this.page = page; yPp9\[+^j
} ~8+ Zs
} `}\
"Aw c
J)>c9w
r;2^#6/Z
,p a {qne
~ Iuf}D;
2. 编写业务逻辑接口,并实现它(UserManager, r5/0u(\LB
kZ:ZtE
UserManagerImpl) qR{=pR
java代码: HiFUv>,u
P+sW[:
J;e2&gB
/*Created on 2005-7-15*/ >U>(`r*
package com.adt.service; !qg`/y9
Zi
i
import net.sf.hibernate.HibernateException; l)\! .X
JbbzV>
import org.flyware.util.page.Page; q`-N7 ,$T
3hH<T.@)
import com.adt.bo.Result; _H%c;z+
]6`%
/** J@'wf8Ub
* @author Joa aXYY:;
*/ /6*42[r
publicinterface UserManager { R n[cW5Y<
\\qZl)P_
public Result listUser(Page page)throws ND;#7/$>
{tZ.v@
HibernateException; ki!0^t:9
[q-h|m
} <'*LRd$1
Gd=RyoJl
2ilQXy
Hn"RH1Zy
r19
pZAc
java代码: IJ"q~r$
`^&OF uee
T5h
H
/*Created on 2005-7-15*/ T8g$uFo
package com.adt.service.impl; K%oG,-wdg
L4HI0Mx
import java.util.List; ZE}}W_
~>|ziHx
import net.sf.hibernate.HibernateException; i/4>2y9/F4
:o3N;*o>)0
import org.flyware.util.page.Page; y)@wjH{6
import org.flyware.util.page.PageUtil; L8B!u9%
MTn{d
import com.adt.bo.Result; sgFEK[w.y
import com.adt.dao.UserDAO; 7<R E_/]
import com.adt.exception.ObjectNotFoundException; Zy/_
E@C}u
import com.adt.service.UserManager; 4Nsp<Kn>
e^voW"?%
/** U K!(G
* @author Joa })%{AfDRF
*/ Zh~'9 JH
publicclass UserManagerImpl implements UserManager { mfr|:i
z b3tIRH
private UserDAO userDAO; ?J0y|
B+`g>h
/** $&c*'3
* @param userDAO The userDAO to set. z$sT !QL~
*/ E1
2uZ$X
publicvoid setUserDAO(UserDAO userDAO){ ~n_HP_Kf?
this.userDAO = userDAO; wCBplaojJ
} nw<uyaU-t
0y\Z9+G:
/* (non-Javadoc) /;$[E
* @see com.adt.service.UserManager#listUser @6.vKCSE
DEgXQ[
(org.flyware.util.page.Page) AbM'3Mkz
*/ <P<z N~i9j
public Result listUser(Page page)throws fz_r7?
ueNS='+m
HibernateException, ObjectNotFoundException { gX@aG9
int totalRecords = userDAO.getUserCount(); lB4WKn=?Kl
if(totalRecords == 0) Z\sDUJ
throw new ObjectNotFoundException BA.uw_^4
WIGi51yC.x
("userNotExist"); E qiY\/S
page = PageUtil.createPage(page, totalRecords); /bmN\I
List users = userDAO.getUserByPage(page); 5)40/cBe
returnnew Result(page, users); k5)om;.w
} n6v6K1
Hn:Crl y#
} q3`u1S7Z7
dh\P4
`D9$v(Ztr
V]^$S"Tv
eS!/(#T
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q2>gU#
B5QFK
询,接下来编写UserDAO的代码: \2z>?i)
3. UserDAO 和 UserDAOImpl: qQa}wcU'9p
java代码: -\MG}5?!
$[|mGae
"N#Y gSr
/*Created on 2005-7-15*/ 2 E=L8<
package com.adt.dao; +C)~bb*
Gw` L"
import java.util.List; '%;m?t%q
.\mj4*?/
import org.flyware.util.page.Page; 2<6UwF
!u hT
import net.sf.hibernate.HibernateException; OrW
JGZBL{8
/** V[V[~;Py
* @author Joa ^rz_f{c]-
*/ $VR{q6[0S?
publicinterface UserDAO extends BaseDAO { IGgL7^MF
s#MPX3itK
publicList getUserByName(String name)throws kGJC\{N5N
x~sBzTa
HibernateException; dWW.Y*339
` %}RNC
publicint getUserCount()throws HibernateException; (?];VG
BLFdHB.$T
publicList getUserByPage(Page page)throws ,)io5nZF
g{LP7D;6
HibernateException; R!1p^~/
#;S*V"
} 4z)]@:`}z
cb bFw
<Z$J<]I
[B3RfCV{
(%9$! v{3
java代码: |?9HU~B
('~LMu_
[ hsds\
/*Created on 2005-7-15*/ $Q0n
package com.adt.dao.impl; f
mGc^d|=
!9x}
import java.util.List; h];I{crh
JI5Dy>u:
import org.flyware.util.page.Page; n !(F, b
\NC3'G:Ii
import net.sf.hibernate.HibernateException; Ca\6vR
import net.sf.hibernate.Query; V.Mry`9-
>d6| ^h'0
import com.adt.dao.UserDAO; Pz^544\~ou
.V*^|UXbHi
/** Dh*n!7lD`
* @author Joa _f{{( 7
*/ PW4q~rc=:
public class UserDAOImpl extends BaseDAOHibernateImpl @pxcpXCy
Js;h%
implements UserDAO { v>56~AJ
W>LR\]Ti@
/* (non-Javadoc) E'8;10s
* @see com.adt.dao.UserDAO#getUserByName 7o4\oRGV
;G!q Y
(java.lang.String) Wjc'*QCPl
*/ -YE^zzh
publicList getUserByName(String name)throws s @C}P
r/1(]#kOX
HibernateException { |g~ZfnP_%
String querySentence = "FROM user in class Y$zSQ_k;U
@8
6f
com.adt.po.User WHERE user.name=:name"; t^L]/$q
Query query = getSession().createQuery *`U~?q}
;nGa.= "L
(querySentence); BuwY3F\-O
query.setParameter("name", name); ry!!9Z>9n
return query.list(); [!z,lY>
} 8-i#8'/x
he4(hX^
/* (non-Javadoc) nrb Ok4Dz
* @see com.adt.dao.UserDAO#getUserCount() % `3jL7|
*/ :-'qC8C
publicint getUserCount()throws HibernateException { kP"9&R`E
int count = 0; Q;u pau
String querySentence = "SELECT count(*) FROM MJvp6n
nR~(0G,H
user in class com.adt.po.User"; ]tD]Wx%
Query query = getSession().createQuery $?Wb}DU7_L
Uv.)?YeGh
(querySentence); ]oxZ77ciL
count = ((Integer)query.iterate().next &vJH$R
2|L&DF:G
()).intValue(); w@b)g
return count; uS-|wYE
} Z7#+pPt!
~V-XEQA
/* (non-Javadoc) P%6~&woF
* @see com.adt.dao.UserDAO#getUserByPage <N)oS-m>
G#CXs:1pd+
(org.flyware.util.page.Page) q@&6#B
*/ d@^ZSy>L2
publicList getUserByPage(Page page)throws G"6 !{4g
+:f"Y0
HibernateException { ,>M[@4`,U
String querySentence = "FROM user in class S:Hl/:iV
"zc l|@
com.adt.po.User"; @oNXZRg6
Query query = getSession().createQuery %RVZD#zr
-12U4h<e
(querySentence); >Q/Dk7 #
query.setFirstResult(page.getBeginIndex()) /mHqurB
.setMaxResults(page.getEveryPage()); #QPjkR|\
return query.list(); O8o3O
6[Y
} u y+pP!<
~dSr5LUD
} : +u]S2u{
92c HwWZ!
FlQGgVN
[m -bV$-d
=v\.h=~~
至此,一个完整的分页程序完成。前台的只需要调用 ,_P-$lB
9$Y=orpWxr
userManager.listUser(page)即可得到一个Page对象和结果集对象 7,MR*TO,
jylD6IT
的综合体,而传入的参数page对象则可以由前台传入,如果用 +_`7G^U?%
D=$)n_F
webwork,甚至可以直接在配置文件中指定。 1cDF!X]
teP<!RKNb
下面给出一个webwork调用示例: Kq!3wb;
java代码: I'Hf{Erw
:]"V-1#}
Pfh mo $
/*Created on 2005-6-17*/ 3R/bz0 V>
package com.adt.action.user; Smh,zCc>s
5(2;|I,T
import java.util.List; 3^ClAE"8
>l m&iF3y
import org.apache.commons.logging.Log; eE Kf|I
import org.apache.commons.logging.LogFactory; k+/6$pI
import org.flyware.util.page.Page; m~|40)
]|@^1we
import com.adt.bo.Result; 54,er$$V
import com.adt.service.UserService; \wZe] G%S
import com.opensymphony.xwork.Action; 5G#n"}T
@WhHUd4s
/** ,6/V"kqIP
* @author Joa sA~]$A;DM!
*/ `^vE9nW7
publicclass ListUser implementsAction{ V#HuIgf-
x;S @bY
privatestaticfinal Log logger = LogFactory.getLog cL ]1f
aXVFc5C\
(ListUser.class); 0Gk<l{o?^
NbobliC=
private UserService userService; GdwVtqbX
Xvv6~
private Page page; _!6jR5&r,
I]575\bA
privateList users; '91/md5
?[AD=rUC
/* b}f~il
* (non-Javadoc) ^~dWU>
* ZNoDFf*h
* @see com.opensymphony.xwork.Action#execute() 8}[).d160
*/ 4Ig;3 ^%71
publicString execute()throwsException{ g-A-kqo9
Result result = userService.listUser(page); IPk4
;,
page = result.getPage(); ok[i<zl;'
users = result.getContent(); uZ5p#M_
return SUCCESS; D-c4EV
} i. "v4D
. vV|hSc
/** \G[$:nS
* @return Returns the page. \zkg
*/ 2HdC |$_+
public Page getPage(){ )UR7i8]!0
return page;
DrR@n~
} \<' ?8ri#
KwS@D9bok
/** L_T5nD^D
* @return Returns the users. +rd+0 `}C
*/ xEI%D|)<
publicList getUsers(){ +whDU2 "
return users; ,prf;|e?
} WcAkCH!L
w>gYx(8b
/** T[gv0|+
* @param page 3S{/>1Y
* The page to set. [WmM6UEVS
*/ wT@og|M
publicvoid setPage(Page page){ $i&zex{\
this.page = page; t_^4`dW`
} HfVZ~PP
Hka2
/** (>Em^(&
* @param users A"]YM'.
* The users to set. p{_" bB
*/ Y4-t7UlS;
publicvoid setUsers(List users){ Ac@VGT:9
this.users = users; 7dWS
} 7! Nsm
R&&4y 7
/** (=0.in Z
* @param userService 8tL~FiHb"
* The userService to set. LV Ge]lD
*/ ]gOy(\B
publicvoid setUserService(UserService userService){ 1Mzmg[L8
this.userService = userService; =bOW~0Z1
} W1~0_;
} :;}P*T*PU
?`s8 pPc4
ye&;(30Oq
}vuO$j
fhiM U8(&
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, ?,mmYW6TjB
?s01@f#
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 Cdn J&N{
/v{I
么只需要: js(pC@<q5
java代码: t Q)qCk07
D*jM1w_`
04ui`-c(
<?xml version="1.0"?> (.:e,l{U%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork p K*TE5]
I7onX,U+
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 7Q 3 k7
?<!|
1.0.dtd"> wk^B"+Uhy
kiEa<-]
<xwork> O-wzz
O.? JmE
<package name="user" extends="webwork- f*Hr^b}`8
YK_7ip.a[
interceptors"> dysS9a,
-).C
<!-- The default interceptor stack name '1[Ft03
OUnA;_
--> Z,gk|M3.
<default-interceptor-ref j 7B!h|
0GwR~Z}Z
name="myDefaultWebStack"/>
a?1Wq
}MySaL>
<action name="listUser" l1I#QB@5n
5P bW[
class="com.adt.action.user.ListUser"> Uo49*Mr
<param C!gZN9-
&{:-]g\
name="page.everyPage">10</param> e-;}366}
<result T{"(\X$
+@UV?"d
name="success">/user/user_list.jsp</result> ?dTD\)%A
</action> rv;3~'V
~*7]r`6\@
</package> 'u658Tj
y_,bu^+*
</xwork> *8q.YuZ
4-w{BZuS
qs6aB0ln
{
w_e9W bi
gw(z1L5
n
{g6%(X\r.r
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 2oW"'43X
N`i/mP
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。 -Za/p@gM
)u">it+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 INf&4!&h
@HW*09TG
|ZBw<f
:&Nbw
P>L +t`'
我写的一个用于分页的类,用了泛型了,hoho E7hhew
eyaNs{TV
java代码: ^.tg 7%dJ
=41xkAMnk
X]=t>
package com.intokr.util; <i[HbgUlO.
^aQ"E9
import java.util.List; Cw%{G'O
$(
)>g>%
/** Bx!-"e
* 用于分页的类<br> -di o5a
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !wNO8;(
* 67TwPvh
* @version 0.01 BVm0{*-[|
* @author cheng _ |p8M!
*/ BY*Q_Et
public class Paginator<E> { h![#;>(
privateint count = 0; // 总记录数 +"(jjxJm
privateint p = 1; // 页编号 CARzO7b\w
privateint num = 20; // 每页的记录数 u>$t'
privateList<E> results = null; // 结果
xPgBV~
/=h` L,
/** DJir { \F
* 结果总数 ;=@0'xPEa-
*/ }Lv;!
publicint getCount(){ 8Y3I0S
return count; SaCh
7 ^
} 1}37Q&2
R3!t$5HG
publicvoid setCount(int count){ C?Ucu]cW
this.count = count; 2oU_2P
} G`zm@QL
kLY^!
/** j9,P/K$:w
* 本结果所在的页码,从1开始 Tr|JYLwF
* .o8t+X'G
* @return Returns the pageNo. @KA4N`
*/ H[UlY?&+
publicint getP(){ ^&)|sP
return p; *dF>_F
} DN/YHSYK
*J{+1Ev~$p
/** W`&hp6Jq
* if(p<=0) p=1 ,PZ ge
* qVPeB,kIz
* @param p {^'HL
*/ iOdpM{~*
publicvoid setP(int p){ kR9-8I{J
if(p <= 0) 7Qsgys#/=
p = 1; iCyfOh
this.p = p; v@Ox:wl>
} 3~\[7I/
aoTP[Bp
/** v3qA":(w+(
* 每页记录数量 I0a<%;JJW
*/ XlJZhc
publicint getNum(){ <,(,jU)j
return num; MfQ!6zE
} wAd9
fzA9'i`
/** "\=U)CJ
* if(num<1) num=1 z] Ue|%K
*/ qFNes)_r
publicvoid setNum(int num){ j=J/x:w_e
if(num < 1) d| {r5[&
num = 1; !a<ng&H^U
this.num = num; E P+J
N
} m6djeOl
j5ve2LiFV%
/** p$>l7?h
* 获得总页数 gO^gxJ'0t
*/ N?>vd*
publicint getPageNum(){ 8*fv'
return(count - 1) / num + 1; ~nPtlrQa#*
} +{UcspqM
e$pV%5=
/** mQ=#nk$~g
* 获得本页的开始编号,为 (p-1)*num+1 {V-v-f
*/ c=+!>Z&i$G
publicint getStart(){ 4H-'Dr=G
return(p - 1) * num + 1; "T"h)L<
} Ow077v?
l (%1jC8
/** ]cN1c}
* @return Returns the results. 6DWgl$[[
*/ T n}s*<=V
publicList<E> getResults(){ yOg+iFTr
return results; 69 o7EA
} EyLu O-5
So
5N5,u@=
public void setResults(List<E> results){ /OJ`c`>Q:
this.results = results; 6i*sm.SDw
} XGMiW0j0B
FkRo
_?
public String toString(){ y|q3Wa
StringBuilder buff = new StringBuilder
EU/8=JA1
X~i<g?]
(); (@}!0[[^
buff.append("{"); vA.MRu#
buff.append("count:").append(count); O,A{3DAe0
buff.append(",p:").append(p); v]c6R-U
buff.append(",nump:").append(num); S/I /-Bp~
buff.append(",results:").append :Xd<74Nu
*
+wW(#[
(results); C{XmVc.
buff.append("}"); Zoc0!84<z
return buff.toString(); jMDY(mwt
} 0,8okAH
wg]LVW}
} 9
5RBO4w%w
)@'}\_a3[]
'oC)
NpnH