Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~IhAO}1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4o>y9
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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 #W\}v(Ke
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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 Okq,p=D6
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分页支持类: +!lDAkW0
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java代码: m*^)#
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package com.javaeye.common.util; =D<0&M9C
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import java.util.List; Ft5A(P >
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publicclass PaginationSupport { *)m:u :
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publicfinalstaticint PAGESIZE = 30; Dka,v
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privateint pageSize = PAGESIZE; ^'3c%&Zf3
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privateList items; *g5bdQ:Av~
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privateint totalCount; OG$n C
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privateint[] indexes = newint[0]; e5_Hmuk|
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privateint startIndex = 0; w>W #cTt
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public PaginationSupport(List items, int Zue3Z{31T
zx@!8Z
totalCount){ <Gpji5f2
setPageSize(PAGESIZE); $dfc@Fn^x
setTotalCount(totalCount); }M4dze
setItems(items); s|C[{n<_
setStartIndex(0); O_QDjxj^rZ
} ,gV#x7IW
uFr12ZFgK
public PaginationSupport(List items, int 0/HFLz'
Q,?_;,I}
totalCount, int startIndex){ /@:X0}L
setPageSize(PAGESIZE); ^ ` LqNG
setTotalCount(totalCount); P2n8H Fi
setItems(items); 7FH(C`uKi
setStartIndex(startIndex); _k:8ib2TQ
} !}Xoqamm
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public PaginationSupport(List items, int 0zW*JJxV
-YNpHd/;,
totalCount, int pageSize, int startIndex){ 4DL;Y
setPageSize(pageSize); )>@S8v,(
setTotalCount(totalCount); ]_C"A
setItems(items); ]zx%"SUM
setStartIndex(startIndex); h@RpS8!Bi
} ^ITF*
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publicList getItems(){ rHKO13WF
return items; d(IJ-qJN
} bi8_5I[
qU26i"GHp
publicvoid setItems(List items){ v_KO xV:<`
this.items = items; e!6yxL*[@[
} ebA95v`Vms
=$OGHc
publicint getPageSize(){ suE K;Bk9
return pageSize; bM?gAY]mB8
} 7O1MC 8{
'$FF/|{
publicvoid setPageSize(int pageSize){ oAO{4xP
this.pageSize = pageSize; XG|N$~N+ 2
} (d4btcg
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publicint getTotalCount(){ [8T{=+k
return totalCount; Y`~B> J
} ]I|(/+}M
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publicvoid setTotalCount(int totalCount){ sVx}(J
if(totalCount > 0){ "_/ih1z]
this.totalCount = totalCount; HH*y$
int count = totalCount / fd[N]I3
dWz?`B{'
pageSize; [}szM^
if(totalCount % pageSize > 0) :
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count++; s)Y1%#
indexes = newint[count]; Vh~hfj"
for(int i = 0; i < count; i++){ Snk+ZQ-
indexes = pageSize * $w(RJ/
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i; ((ebSu2-?$
} ?^VPO%
}else{ ZR1U&<0c@
this.totalCount = 0; FKO2UY#&7
} `D ;*.zrA
} pGD@R=8
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publicint[] getIndexes(){ VAiJL
return indexes; M5{#!d}^D
} "pkdZ
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publicvoid setIndexes(int[] indexes){ ]g-%7g|
this.indexes = indexes; {+9RJmZg
} Y
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publicint getStartIndex(){ z}E_wg
return startIndex; y#'hOSR2
} )$] lf }
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publicvoid setStartIndex(int startIndex){ i#-v4g
if(totalCount <= 0) l cl|o3yQ
this.startIndex = 0; hDxq9EF
elseif(startIndex >= totalCount) #Hrzk!&9
this.startIndex = indexes L/"MRQ"
HAjl[c
[indexes.length - 1]; W6<oy
elseif(startIndex < 0) F! !HwI
this.startIndex = 0; >!Yuef
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else{ xr'1CP
this.startIndex = indexes +vkmS
l!*_[r
[startIndex / pageSize]; +gd5&
} Ef] Hpjvp
} 3en9TB
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publicint getNextIndex(){ :|;@FkQ
int nextIndex = getStartIndex() + [v~,|N>w
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pageSize; Y(Oh7VwY*P
if(nextIndex >= totalCount) lp}S'^ y
return getStartIndex(); ujV{AF`JfB
else N,TV?Q5l7
return nextIndex; R!dC20IMvH
} ,4'gj0
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publicint getPreviousIndex(){ c`<2&ke
int previousIndex = getStartIndex() - 3y)\dln
PCl5,]B}
pageSize; ~xd?y*gk;
if(previousIndex < 0) O|H:
return0; &vrQ *jX
else r,;ca6>5H
return previousIndex; DMUirA;
} ^Wld6:L{I
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} uo`R
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抽象业务类 g, d_
java代码: 2iNLm6"
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/** E`TZ:W]r,
* Created on 2005-7-12 ?W'z5'|
*/ `O6#-<>
package com.javaeye.common.business; ]c>@RXY'
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import java.io.Serializable; D;YfQQr
import java.util.List; ?I?G+(bq
pX%:XpC!h
import org.hibernate.Criteria; tz):$1X_
import org.hibernate.HibernateException; $0[T<]{/?
import org.hibernate.Session; 7i($/mNl
import org.hibernate.criterion.DetachedCriteria; ZN8j})lE
import org.hibernate.criterion.Projections; # `=Zc7gf
import =2&\<Q_Fi
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org.springframework.orm.hibernate3.HibernateCallback; AQZ<,TE0,
import bqbG+g
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org.springframework.orm.hibernate3.support.HibernateDaoS PIH\*2\/
7.29'
upport; 7wj2-BWa
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import com.javaeye.common.util.PaginationSupport; $5pCfW8>
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public abstract class AbstractManager extends ebze_:
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HibernateDaoSupport { ( 1z"=NCp
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privateboolean cacheQueries = false; hJM&rM7
cb_C2+%8NA
privateString queryCacheRegion; CtY-Gs
b d 1^
publicvoid setCacheQueries(boolean
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*5Zow 3
cacheQueries){ hwGK),?"+
this.cacheQueries = cacheQueries; n~629 &
} d.+*o
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publicvoid setQueryCacheRegion(String :-{"9cgFR
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queryCacheRegion){ %gmx47
this.queryCacheRegion = Bj7*2}
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queryCacheRegion; y11^q*}
} 1]If<
<
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publicvoid save(finalObject entity){ Xy(QK2|
getHibernateTemplate().save(entity); c=u+X`
Q
} 4$R!)
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publicvoid persist(finalObject entity){ |*?N#0s5h
getHibernateTemplate().save(entity); c';~bYZ
} Fu.aV876\f
&6\&McmkX
publicvoid update(finalObject entity){ `sm Cfh}j6
getHibernateTemplate().update(entity); ]\yB,
} I<QUvs%e
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publicvoid delete(finalObject entity){ Q+1ot,R
getHibernateTemplate().delete(entity); 8fqabR
} p&Qb&nWk<
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publicObject load(finalClass entity, |it*w\+M
>Cr"q*
finalSerializable id){ +c_AAMe
return getHibernateTemplate().load s{dm,|?Jl,
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(entity, id); IGTO|sT"
} zh) &6'S\
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publicObject get(finalClass entity, "c[> >t
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finalSerializable id){ b=Nsz$[
return getHibernateTemplate().get ^x&x|ckR!
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(entity, id); u[qy1M0
} x[t?hl=:
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publicList findAll(finalClass entity){ Gxd/t#;
return getHibernateTemplate().find("from `&NFl'l1C
XI`_PQco
" + entity.getName()); Kvg=7o
} !po,Z&
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publicList findByNamedQuery(finalString q-t%spkl
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namedQuery){ vE9"1M
return getHibernateTemplate b#I,Z+0ry
'\{ OQH
().findByNamedQuery(namedQuery); 6Y [&1c8
} s>;"bzzq
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publicList findByNamedQuery(finalString query, il>+jVr
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finalObject parameter){ |6NvByc,
return getHibernateTemplate :vi %7
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().findByNamedQuery(query, parameter); L^e*_q2d:>
} 05ZYOs }
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publicList findByNamedQuery(finalString query, 87[o^) 8
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finalObject[] parameters){ 3R/6/+S-
return getHibernateTemplate ~^.,Ftkb@7
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().findByNamedQuery(query, parameters); @dQr^'h
} Yy
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publicList find(finalString query){ hak#Iz0[C
return getHibernateTemplate().find Db2#QQ
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(query); IO#)r[JZ
} {$ N\@q@v~
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publicList find(finalString query, finalObject (a!E3y5,
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parameter){ r;f\^hVy
return getHibernateTemplate().find HV`u#hZ7C
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(query, parameter); G%gdI3h1Z
} 0D:uM$
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public PaginationSupport findPageByCriteria aJm5`az)
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(final DetachedCriteria detachedCriteria){ &[\zs&[@y
return findPageByCriteria R(Vd[EGY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); yq3"VFh3d
} ?_pd#W=!
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public PaginationSupport findPageByCriteria jM*wm~4>@
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(final DetachedCriteria detachedCriteria, finalint .f!'>_
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startIndex){ ^?%ThPo_
return findPageByCriteria EHe-wC
fR.raI4et
(detachedCriteria, PaginationSupport.PAGESIZE, PmId #2f
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startIndex); D622:Y886
} Zo-Au
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public PaginationSupport findPageByCriteria \i~5H]?d
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(final DetachedCriteria detachedCriteria, finalint E3Z>R=s
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pageSize, KJ?/]oLr0
finalint startIndex){ TuMZHB7h;
return(PaginationSupport) \l6mXIn=>
~$a%& ]\
getHibernateTemplate().execute(new HibernateCallback(){ ^1}ffE(3>
publicObject doInHibernate +&AU&2As
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(Session session)throws HibernateException { x2i`$iNhmP
Criteria criteria = Fo"'[`
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detachedCriteria.getExecutableCriteria(session); jP@t!=
int totalCount = iEFS>kL8e
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((Integer) criteria.setProjection(Projections.rowCount jM@@N.
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()).uniqueResult()).intValue(); 43J8PMY
criteria.setProjection }=3W(1cu-
HSl$ U0
(null); ]*S_fme
List items = ,/L_9wV-\
1 _W5@)
criteria.setFirstResult(startIndex).setMaxResults N_!Zn"J
of<>M4/g4y
(pageSize).list(); K3UG6S\B
PaginationSupport ps = Q!%CU8!`&
I(WND/&
new PaginationSupport(items, totalCount, pageSize, \t&6$"n(B6
!as<UH"\
startIndex); sEfGf.
return ps; xcIZ'V
} ^?[^o\/@R
}, true); Z42v@?R.!W
} EZiGi[t7
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public List findAllByCriteria(final : [vp.vw}/
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DetachedCriteria detachedCriteria){ [dL?N
return(List) getHibernateTemplate b_Ky@kp
oB Bdk@
().execute(new HibernateCallback(){ J=]w$e ?.P
publicObject doInHibernate Zr2QeLQC(
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(Session session)throws HibernateException { 0\}j[-`pF
Criteria criteria = Y=rW.yK8
Js#c9l{{
detachedCriteria.getExecutableCriteria(session); zZh`go02E
return criteria.list(); M!6bf
} z8"=W,2
}, true); |V~P6o(/
} kAk,:a;P
GrQAho
public int getCountByCriteria(final NtOR/*
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DetachedCriteria detachedCriteria){ "AVj]jR
Integer count = (Integer) k~?}z.g(
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getHibernateTemplate().execute(new HibernateCallback(){ ?R{?Qv
publicObject doInHibernate (U dDp"/
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(Session session)throws HibernateException { !`#9#T|
Criteria criteria = WE~3(rs#X#
qP<,"9!I
detachedCriteria.getExecutableCriteria(session); \M532_w
return UZX)1?U
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criteria.setProjection(Projections.rowCount 8"*$e
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()).uniqueResult(); |~CnELF)
} YL=k&QG
}, true); gS|xicq!
return count.intValue(); +m7x>ie)
} 6$dm-BI
} $xZk{ rK
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用户在web层构造查询条件detachedCriteria,和可选的 x)yf!Dv5$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 &lS0"`J=
tx1jBh:e=
PaginationSupport的实例ps。 X5/{Mx`8Oz
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ps.getItems()得到已分页好的结果集 O`0$pn
ps.getIndexes()得到分页索引的数组 I~qiF%?d
ps.getTotalCount()得到总结果数 4K;j:ZJ"x
ps.getStartIndex()当前分页索引 ry]7$MQyV
ps.getNextIndex()下一页索引 v#+w<gRq
ps.getPreviousIndex()上一页索引 Y-c~"#
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omA*XXUx=8
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 `U3
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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 CzEn_ZMb
Mqtp}<*@-
一下代码重构了。 +r!h* 4
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我把原本我的做法也提供出来供大家讨论吧: fDqXM;a"
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首先,为了实现分页查询,我封装了一个Page类: $B?7u@>,
java代码: (}}8DB
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/*Created on 2005-4-14*/ ck~xj0
package org.flyware.util.page; g&vEc1LNo
bX(*f>G'
/** wqOhJYc
* @author Joa ,;-*q}U
* L K~,
*/ Qd4T?5 vG
publicclass Page { ncdr/(`
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/** imply if the page has previous page */ ,h._iO)I^
privateboolean hasPrePage; p,8Z{mLn
bN&da
[K
/** imply if the page has next page */ VT7NWTJ,
privateboolean hasNextPage; "'#Hh&Us
&Kp+8D*
/** the number of every page */ U}0/V
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privateint everyPage; DS2$ w9!
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/** the total page number */ @#tSx
privateint totalPage; 9.=#4OH/
8W>l(w9M
/** the number of current page */ dSZ#,Ea"
privateint currentPage; //@=Q!MW
m6cW
/** the begin index of the records by the current [AzN&yACE
fNJ;{
query */ ;LE
@Ezx
privateint beginIndex; fdG.=7`
6I#DlAU@v
$IT9@}*{
/** The default constructor */ wcf_5T
public Page(){ ACYn87tq
rfi`Bp
} FO=1P7
m_ m@>}ud
/** construct the page by everyPage OP}p;(
* @param everyPage \AzcW;03g[
* */ AyO|9!F@A
public Page(int everyPage){ BD-=y
this.everyPage = everyPage; K:@=W1
} I}IW!K
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^
/** The whole constructor */ QZox3LM1&.
public Page(boolean hasPrePage, boolean hasNextPage, [9_ (+E[}
Gnt!!1_8L
+:%FJCOT
int everyPage, int totalPage, K>6k@okO
int currentPage, int beginIndex){ s*~o%emw
this.hasPrePage = hasPrePage; DZ.trtK
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; Sg>0P*K@
this.totalPage = totalPage; !y~b;>887
this.currentPage = currentPage; j]"xck
this.beginIndex = beginIndex; !@Lc/'w
} 9nS!
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;
/** xN8JrZE&
* @return SqF.DB~
* Returns the beginIndex. !gHWYWu)!
*/ :[f`HY&
publicint getBeginIndex(){ QS*cd|7J;
return beginIndex; X",0VO
} f94jMzH9z
wP0+Xv,
/** c@7hLUaE2
* @param beginIndex O
f @#VZ
* The beginIndex to set. So.P @CCd
*/ mS}x2&
publicvoid setBeginIndex(int beginIndex){ `j}d=zZ
this.beginIndex = beginIndex; b|o!&9Yyr
} TeCpT2!5j
!gfhEzY
/** _C,@eu"9V
* @return f\U&M,L\'
* Returns the currentPage. @[lc0_b
*/ oImgj4C2L
publicint getCurrentPage(){ AWXpA1(
return currentPage; ?lN8~Ze
} M2Fj)w2
'#PqI)P
/** wKS-O%?
* @param currentPage jZT :-w
* The currentPage to set. &MZy;Sq
*/ lN>C#e<]
publicvoid setCurrentPage(int currentPage){ `Uj?PcS_
this.currentPage = currentPage; D8AIVK]
} `{lAhZ5
Guw|00w,Q$
/** OrEuQ-,i@
* @return k5;Vl0Ho
* Returns the everyPage. KI@
*/ xf"5<PTW</
publicint getEveryPage(){ aC~n:0v
return everyPage; *8.@aX3
} ]_: TrH
kefv=n*]l
/** N^(lUba
* @param everyPage "=\_++
* The everyPage to set. 6eYf2sZ;J
*/ =l2Dm
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; 0O,T=z[+>
} s7nX\:Bw:
9me}&Fdr
/** 1~5q:X
* @return -jtC>_/
* Returns the hasNextPage. 14n="-9
*/ -N8cjr4l
publicboolean getHasNextPage(){ dEd ]U49u
return hasNextPage; B5,QJ W*
} k)usUP'
koEX4q
/** UcLNMn|
* @param hasNextPage Ig Vo%)n
* The hasNextPage to set. }pE~85h4M
*/ zP(=,)d
publicvoid setHasNextPage(boolean hasNextPage){ vV6Lp
this.hasNextPage = hasNextPage;
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} (21 W6
tdnXPxn[
/** 2iPmCG
* @return O(D5A?tv!
* Returns the hasPrePage. mk%"G =w
*/ S`@6c$y k
publicboolean getHasPrePage(){ H8-D'q>R
return hasPrePage; *M&VqG4P9w
} 3_\{[_W
2@3.xG
/** }x?H ~QQT
* @param hasPrePage 1KYbL8c
* The hasPrePage to set. 8S1P&+iKs
*/ RHx+HBZ
publicvoid setHasPrePage(boolean hasPrePage){ )0U3w#,JQ
this.hasPrePage = hasPrePage; !<=%;+
} EN-H4F
..q63dr
/** v= *Bb3dt
* @return Returns the totalPage. 5&<d2EG6l'
* 3cCK"kr
*/ @UpC{M--Wr
publicint getTotalPage(){ hk@`N;dn
return totalPage; B]|6`UfB
} vNz;#Je
,zN3? /7
/** pdi=6<?bd
* @param totalPage 6/[Z178m
* The totalPage to set. ^5;vx
*/ T1(j l)
publicvoid setTotalPage(int totalPage){ &8]#RQy{f
this.totalPage = totalPage; UEEBWz H
} 7bonOt
Y
ke}Y2sB
} ,ykPQzO
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uS,p|}Q&
bvipbf[m<
nxyjL)!)0
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 /i{tS`[F2a
~IlF*Zz#}6
个PageUtil,负责对Page对象进行构造:
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java代码: >,>;)B@J
aJ6#=G61l
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/*Created on 2005-4-14*/ kUn2RZ6$#
package org.flyware.util.page; llHc=&y#
.Na&I)udX.
import org.apache.commons.logging.Log; }iua]
4|
import org.apache.commons.logging.LogFactory; 9u?)vR[@e
}z%OnP
/** =de<WoKnu2
* @author Joa +z:CZ(fb
* b|sc'eP#?
*/ @PPR$4
publicclass PageUtil { a{]g+tGH
]~ !XiCqu
privatestaticfinal Log logger = LogFactory.getLog *?_qE
cc|CC
Zl
(PageUtil.class); *.m{jgi1X
r"{Is?yKe
/** 6kt]`H`cfJ
* Use the origin page to create a new page ,4H;P/xsb
* @param page i1qS ns
* @param totalRecords Jo{zy
* @return ~~C6)N~1
*/ 0).fBBNG
publicstatic Page createPage(Page page, int T!l
mO? Q
[3j$ 4rP
totalRecords){ L w>-7)
return createPage(page.getEveryPage(), F8{ldzh
6IEUJ-M Z
page.getCurrentPage(), totalRecords); eM?rc55|
} ta&Q4v&-
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/** e7@li<3>d
* the basic page utils not including exception %{R_^Y8t
|x &Z~y
handler XVQL.A7
* @param everyPage [AXsnpa/C
* @param currentPage |EF>Y9
* @param totalRecords b/}'Vf[
* @return page a(8>n
Z,V
*/ $brKl8P
publicstatic Page createPage(int everyPage, int ;#3ekl{-g
\s=QiPK
currentPage, int totalRecords){ Bu7A{DRf
everyPage = getEveryPage(everyPage); X_D6eYF
currentPage = getCurrentPage(currentPage); >9-Dd)<
int beginIndex = getBeginIndex(everyPage, 0jBKCu
MWBXs75I
currentPage); 9c#lLKrzG
int totalPage = getTotalPage(everyPage, RK?jtb=&A
xN6?yr
totalRecords); It%T7
X#
boolean hasNextPage = hasNextPage(currentPage, $ "Afy)Ir
fO*)LPen.z
totalPage); "
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boolean hasPrePage = hasPrePage(currentPage); hIR@^\?
qh%i5Mu
returnnew Page(hasPrePage, hasNextPage, oG!6}5
everyPage, totalPage, "?$L'!bM@
currentPage, 6|QTS|!
/sy-;JDnsu
beginIndex); csYy7uzi
} r+o_t2_b*
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privatestaticint getEveryPage(int everyPage){ 4Mk8Cpz
return everyPage == 0 ? 10 : everyPage; f,|QAj=a
} MzcB3pi
x'@W=P 7
privatestaticint getCurrentPage(int currentPage){ ^>-+@+(
r
return currentPage == 0 ? 1 : currentPage; qtO1hZ
} 9*' &5F=
w{3ycR
privatestaticint getBeginIndex(int everyPage, int >GgE,h
bn $)f6%
currentPage){ ,ohmc\*J
return(currentPage - 1) * everyPage; 9+}cE**=d
} ]* 0(-@
19'5Re&
privatestaticint getTotalPage(int everyPage, int _0K.Fk*(!
f6Ml[!aU
totalRecords){ X1Qr_o-BR
int totalPage = 0; ThtMRB)9
6_WmCtvF
if(totalRecords % everyPage == 0) Z%#^xCz;w>
totalPage = totalRecords / everyPage; |7y6
pz
else {t&*>ma6)
totalPage = totalRecords / everyPage + 1 ; d [r-k 2
J<rlz5':
return totalPage; :i.t)ES
}
m;c3Z-
Wj&nUp{
privatestaticboolean hasPrePage(int currentPage){ $|k%@Q>
return currentPage == 1 ? false : true; l_6e I
} xpAok]
^CUSlnB\(
privatestaticboolean hasNextPage(int currentPage, )#a7'Ba
}B`Ku5 M
int totalPage){ WVOoHH
return currentPage == totalPage || totalPage == P7Xg{L&@.
"v5ElYG
0 ? false : true; rS4%$p"
} (Ux[[
[,rn3C A
i0\)%H:z
} ?IILt=)<
iUTU*El>
tU{\ev$x
8fh4%#,C%
5Dd:r{{ Q
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 s"WBw'_<<
zZ:xEc
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 w-ALCh8o
Fwb5u!_,
做法如下: aZ6'|S;
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D*QYKW=)
KU]ok '
的信息,和一个结果集List: Ps3~{zH`
java代码: .%IslLZ
g8RPHjvZ
h,t:]
/*Created on 2005-6-13*/ ;g+]klR!
package com.adt.bo; CcY7$D
NO2(vE
import java.util.List; 6T_K9
6Cv.5Vhx
import org.flyware.util.page.Page; P6.!3%y
T cJ$[
/** tb,9a!?
* @author Joa Plfdr~$
*/ B$?^wo
publicclass Result { 9,scH65x
_w>uI57U
private Page page;
]ENK8bW
{~_Y _-
private List content; Bd&`Xfebj
WI&lj<*
/** gw+eM,Yp
* The default constructor &iBNO,v
*/ CW p#^1F
public Result(){ 1'Rmg\(
super(); W:vr@e6
} FY4 T(4#
F?BS717qS%
/** cDIBDC
* The constructor using fields 6e.[,-eU
* f@d9Hqr+l;
* @param page yQ%"U^.m
* @param content nxfoWy
*/ ~8{sA5y
public Result(Page page, List content){ O m9jtWk
this.page = page; _{)9b24(
this.content = content; s$ z2 c
} T<yb#ak
KmmQ ,e%
/** 4x=(Zw_X
* @return Returns the content. ~KPv7WfG
*/ 4-^[%&>}
publicList getContent(){ C?o6(p"b
return content; )+EN$*H
} |>+uw|LtZ
Oaa"T8t
/** (%'9CfPx
* @return Returns the page. .Y\EE;8%
*/
qybxXK:
public Page getPage(){
^2C>L}
return page; /iG7MC\`
} p!DP`Ouc3\
4TZ cc|B5
/** J#
EP%
* @param content 5FOqv=6S
* The content to set. jDX>izg;V
*/ -[heV| $;
public void setContent(List content){ {v,)G)obWw
this.content = content; -c+]Wm"\
} i=#F)AD^5#
9]7u_
/** h/m6)m.D
* @param page 5k$vlC#[H
* The page to set. WU)Ss`s \
*/ gKi{Y1
publicvoid setPage(Page page){ N'?u1P4G
this.page = page; bK*~ol
} ^RNOcM|
} S|AjL
Ng#
kO_5|6
Ll}yJ#3,
K 1W].(-@4
KY.ZT2k
2. 编写业务逻辑接口,并实现它(UserManager, 76@qHTh}
H=~9CJ+tc
UserManagerImpl) f~ U.a.Fb
java代码: >5ChcefH
,;jGJr
8ObeiVXf)
/*Created on 2005-7-15*/ f^b K=#
package com.adt.service; ^sClz*%?
N$#\Xdo
import net.sf.hibernate.HibernateException; iqPBsIW
'*T]fND4
import org.flyware.util.page.Page; #*^+F?o,(
5-vo0:hk
import com.adt.bo.Result; "pvH0"Q*
%l!xkCKA
/** OZ(dpV9.S
* @author Joa xDjV`E]
*/ T?wzwGp-[
publicinterface UserManager { |"Z{I3Umg
qLK?%?.N<
public Result listUser(Page page)throws Jp~zX
lu
X.V[0$.;
HibernateException; cUk*C
\?lz&<
} qTmD'2
,hRN\Kt)p
$>q@SJ1q
1cC1*c0Z
c0rk<V%5+
java代码: m9":{JI.w
Im?LIgt$
#b)e4vwCq
/*Created on 2005-7-15*/ 7~UR!T9
package com.adt.service.impl; KoBW}x9Jp
DuF"*R~et
import java.util.List; {hdPhL
dh -,E
import net.sf.hibernate.HibernateException; d)ahF[82
qJv[MBjk3B
import org.flyware.util.page.Page; r'4:)~]s
import org.flyware.util.page.PageUtil; eJ@~o{,?>
yVJ%+d:6
import com.adt.bo.Result; zT9JBMNE:
import com.adt.dao.UserDAO; j*R,m1e8
import com.adt.exception.ObjectNotFoundException; K8[DZ)rO;Z
import com.adt.service.UserManager;
%X1x4t]
z`3( ,V
/** l67Jl"v
* @author Joa B[o`k]]
*/ kOrl\_!z3
publicclass UserManagerImpl implements UserManager { ^ c%N/V
\
T.:+3:8|F
private UserDAO userDAO; B80aw>M
$l[Rh1z`;+
/** ftbpqp'
* @param userDAO The userDAO to set. 01@t~v3!Z
*/ 7hw .B'7
publicvoid setUserDAO(UserDAO userDAO){ 04@cLDX8uB
this.userDAO = userDAO; =xN= #
} -:Rp'SJ
EL{vFP
/* (non-Javadoc) Dr#c)P~Wd
* @see com.adt.service.UserManager#listUser
8Ogv9
K_&MoyJJ9f
(org.flyware.util.page.Page) 9S7A!AKE
*/ 3Ofc\
public Result listUser(Page page)throws qUJ
aeQ
w=7L3AW
HibernateException, ObjectNotFoundException { E-2eOT
int totalRecords = userDAO.getUserCount(); Y]g?2N=E
if(totalRecords == 0) aUopNmN
throw new ObjectNotFoundException vqdX^m^PY
I PCGt{B~
("userNotExist"); 47>>4_Hz
page = PageUtil.createPage(page, totalRecords); DXR:1w[^
List users = userDAO.getUserByPage(page); R9o- `Wz
returnnew Result(page, users); ,<Kx{+ [h
} i@P}{
j? i#L}.I
} S?0$? w?
oF&l-DHp
,. EBOUW^
DBH#)4do@
k;^
:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 uE5X~
e":G*2a
询,接下来编写UserDAO的代码: vGd1w%J-
3. UserDAO 和 UserDAOImpl: PAF8Wlg
java代码: 9$*s8}|
7<\C?`q"
"&+3#D
>
/*Created on 2005-7-15*/ 5FeFN)
package com.adt.dao; @'2m$a
t*S."
q
import java.util.List; hGTV;eU
*C|
import org.flyware.util.page.Page; :l\V'=%9'@
:l u5Uu~
import net.sf.hibernate.HibernateException; O6s.<`\
iJh!KEy~A5
/** Sm{>rR
* @author Joa -G |a*^
*/ 9J-b6,
publicinterface UserDAO extends BaseDAO { %VNlXHO.
#
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publicList getUserByName(String name)throws QO;4}rq
KW3+luI6
HibernateException; Ri*3ySyb
2[yBD-":
publicint getUserCount()throws HibernateException; N:5[,O<m_
|UUdz_i!:
publicList getUserByPage(Page page)throws r?$?;%|C
w}cY6O,1
HibernateException; Q;/a F`
L V{Q,DrP
} >]D4Q<TY
UK[v6".^h
ts~{w;c
[1G^/K"
>!6JKL~=
java代码: gXFWxT8S
cI0 ]}S
d9^E.8p$
/*Created on 2005-7-15*/ r#i?j}F}
package com.adt.dao.impl; \_6OC Vil
,El!fgL
import java.util.List;
#;KsJb)N.
$14:(<
import org.flyware.util.page.Page; vG41C k1
u,.3
import net.sf.hibernate.HibernateException; _"a=8a06G
import net.sf.hibernate.Query; pJIv+
},$0&/>ft
import com.adt.dao.UserDAO; g{k1&|
]3{0J
/** ,T,:-E
* @author Joa si4-3eC
*/ <[ Xw)/#
public class UserDAOImpl extends BaseDAOHibernateImpl A#wEuX=[
I3b"|%
implements UserDAO { [I*!
lbt
xl9aV\W
/* (non-Javadoc) K,ej%Vtz
* @see com.adt.dao.UserDAO#getUserByName 8T[
6J{|C
YNdrWBf)
(java.lang.String) uzOYVN$t
*/ Aj>[z8!,
publicList getUserByName(String name)throws }GwVKAjP
Ka!I`Yf
HibernateException { W~n.Xeu{C
String querySentence = "FROM user in class )$GIN/i
p
zw8 T
com.adt.po.User WHERE user.name=:name"; c7uG9
Query query = getSession().createQuery ~"x5U{K48S
<!d"E@%v@
(querySentence); "8f?h%t
query.setParameter("name", name); j V3)2C}
return query.list(); h!@,8y[B
} E$s/]wnr[
kh$_!BT
/* (non-Javadoc)
g\fhp{gWB
* @see com.adt.dao.UserDAO#getUserCount() ;!>Wz9
*/ R{YzH56M
publicint getUserCount()throws HibernateException { a
dfR!&J
int count = 0; 8TV;Rtl
String querySentence = "SELECT count(*) FROM ;Y9=!.Ak0y
ff?t[GS
user in class com.adt.po.User"; :Sg&0Wj+#j
Query query = getSession().createQuery .>g1$rj
,$*IzL~
(querySentence); )EM7,xMz
count = ((Integer)query.iterate().next eP1nUy=T
5/><$06rq
()).intValue(); ^?"\?M1
return count; bp<^R
} l(W[_ D
\`.F\Z
/* (non-Javadoc) E8\XNG)V4
* @see com.adt.dao.UserDAO#getUserByPage -[7O7'
,V]
]:eR
(org.flyware.util.page.Page) )>\}~s
*/ ,*id'=S
publicList getUserByPage(Page page)throws F'8T;J7
Lz9#A.
HibernateException { 9 ;t]Hp_+K
String querySentence = "FROM user in class M6|I6M<
5E\#%K[
com.adt.po.User"; FVsj;
Query query = getSession().createQuery 83~ i:+;
pcS+o
(querySentence); @ T;L$x
query.setFirstResult(page.getBeginIndex()) FwAKP>6 *
.setMaxResults(page.getEveryPage()); \BV
0zKd
return query.list(); D0G-5}s`
} eitu!=u
CBT>"sYE1
} |f( ~@Q:
|k 2" _
CJknJn3m&
I+
l% Sn#\
^>&k]T`
至此,一个完整的分页程序完成。前台的只需要调用 `g''rfk}
9<Eg}Ic
userManager.listUser(page)即可得到一个Page对象和结果集对象 4Cb9%Q0
_, AzJ^
的综合体,而传入的参数page对象则可以由前台传入,如果用 E|EgB33S
* A|-KKo\
webwork,甚至可以直接在配置文件中指定。 W`rNBfG>
#G]! %
下面给出一个webwork调用示例: FyL_xu\e
java代码: yoe}$f4
imL_lw^?
b;mSQ4+
/*Created on 2005-6-17*/ mg:!4O$K
package com.adt.action.user; iTo k[uJ}
`s#Hq\C
import java.util.List; m`?MV\^
A~(l{g
import org.apache.commons.logging.Log; 2(!fg4#+
import org.apache.commons.logging.LogFactory; KU9Z"9#
import org.flyware.util.page.Page; #Doq P:
SjEAuRDvUz
import com.adt.bo.Result; |+IZS/W"
import com.adt.service.UserService; ,1{Ep`
import com.opensymphony.xwork.Action; hqSJ(gs{
!/{+WHxIr|
/** h~Q)Uy5N(D
* @author Joa >-<8N-@"n
*/ R>@uY(>dJ
publicclass ListUser implementsAction{ Vn=qV3OE]
Q/>L_S
privatestaticfinal Log logger = LogFactory.getLog 2GmpCy`L"
mY!iu(R1
(ListUser.class); ?dZt[vAMn
NF$\^WvYSP
private UserService userService; N[|Nxm0z/C
nxm$}!Df
private Page page; ,.IEDF<&
qa >Ay|92e
privateList users; [&S}dQ"
7cg*|E@
/* -ZOBAG*
* (non-Javadoc) d^ ZMS~\*
* H&}ipaDO
* @see com.opensymphony.xwork.Action#execute() ^t"iX9
*/ #<7O08:
publicString execute()throwsException{ S*)1|~pRvQ
Result result = userService.listUser(page); n}-3o]ku
page = result.getPage(); Ok-.}q>\Mv
users = result.getContent(); ;(6g\'m
return SUCCESS; >cmE
t
} 9?T{}| ?
^D67y%
/** 5x2Ay=s
* @return Returns the page. ~q +[<xR\
*/ *v%rMU7,
public Page getPage(){ h( QYxI,|
return page; 3 *S{;p
} uZKP"Oy
?ne_m:J[
/** v0*N)eqDGd
* @return Returns the users. %!Q`e79g8
*/ N@o?b
publicList getUsers(){ xh@-g|+g
return users; eBN)g^
} g\oSG)
3#kitmV
/** g\A
y`.s
* @param page YMpf+kN
* The page to set. \6|/RFT
*/ w*j$uW6{
publicvoid setPage(Page page){ >ndJNinV
this.page = page; '8FC<=+p[
} }S_oH9A
}_.:+H!@
/** mZk0@C&:6
* @param users 1m<RwI3s
* The users to set. qUF'{K
*/ 4R+.N
publicvoid setUsers(List users){ v*hRz;
this.users = users; .]4W!])9
} RWq{Ff}Hk
/G{_7cb
/** Jwn AW}=
* @param userService 3M*Bwt;F_
* The userService to set. }w-wSkl1
*/ 4_M>OD/"
publicvoid setUserService(UserService userService){ /BKe+]dS*
this.userService = userService; !v#xb3"/
} fg%&N2/(.B
} _,h@:Xij
VU|dV\>
&7?R+ZGo
DsD zkwJE
z;u>
Yz+3
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 0CvsvUN@
z T%U!jqI
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 yTM{|D]$(
F-Z%6O,2
么只需要: ?^HfNp9
java代码: OIb
)8gGv
Aez2*g3
<?xml version="1.0"?> :q3+AtF
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork %6j)=IOts
Q<tu) Qo
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4NEq$t$Jn
Z*{]
,
1.0.dtd"> 3ucP(Ex@tg
CCijf]+
<xwork> 6w3R'\9
nHFrG
=o,
<package name="user" extends="webwork- "LhUxnll
.o{0+fC#
interceptors"> 1tzV8(7
pI`?(5iK6|
<!-- The default interceptor stack name ~.Ik#At
G*
%t'jX9
--> wl=61Mb
<default-interceptor-ref tEd.'D8 s
sf}Dh
name="myDefaultWebStack"/> k4J8O3E
igf)Hb;5
<action name="listUser" Ha>*?`?yI
gv15t'y9
class="com.adt.action.user.ListUser"> UK#&lim
<param 1xyU
W3W'oo
name="page.everyPage">10</param> }`VDD?M
<result <c[U#KrvJ
wHjLd$ +o
name="success">/user/user_list.jsp</result> v'2[[u{7*
</action> 4\t1mocCSN
W~T}@T:EN
</package> #PvB/3
Q3W#`6jpF
</xwork> aAvsb$
4wzlJ19E(
Qq-"Cg@-/
SD\=
m/W
[t\B6XxT
}n,Zl>T9
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 Myat{OF
dth&?/MERL
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。 5@Bu99`
]36sZ
*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qr\!*\9
I<b?vR 'F
VvbFp
MWk:sBCqr
;#G oGb4AM
我写的一个用于分页的类,用了泛型了,hoho jd`},X /
tL
SN`6[:
java代码: xZ5M/YSyG
wle@vCmr
3q[WHwmm
package com.intokr.util; W|k0R4K]]
~%u|[$
import java.util.List; $S*4r&8ZD
Z!xVgM{
/** |xr%6 [Ff
* 用于分页的类<br> v;#=e$%}MO
* 可以用于传递查询的结果也可以用于传送查询的参数<br> {@}?k s5
* .Jb$l$5'w
* @version 0.01 .V9e=yW!*
* @author cheng zboF
1v`
*/ DQ.v+C,
public class Paginator<E> { /(I*,.d
privateint count = 0; // 总记录数 8qi+IGRg
privateint p = 1; // 页编号 x Ha=3n
privateint num = 20; // 每页的记录数 !%<^K.wG
privateList<E> results = null; // 结果 kU5.iK'
4Q=ftY<
/** 3Rg}+[b
* 结果总数 fyz
nuUl
*/ egR9AEJvz
publicint getCount(){ O[17";P
return count; s}&bJ"!Z
} RIM`omM
"yziXT@V
publicvoid setCount(int count){ d&cU*
this.count = count; SQsSa1
} M/D)".;
sGDV]~E
/** j;yf8Nf
* 本结果所在的页码,从1开始 &MR/6"/s
* z9
u$~
* @return Returns the pageNo. D;GD<zC]
*/ qVjWV$j
publicint getP(){ 5lKJll^2:
return p; %ugHhS!
} MJ<Jb ,D1
=6FUNvP#8
/** z><5R|Gf
* if(p<=0) p=1 o{v&.z
*
+1C3`0(
* @param p Ph&urxH@
*/ P27%xV-n>
publicvoid setP(int p){ T[k4lM
if(p <= 0) `"yxdlXA
p = 1; y #f
QPR
this.p = p; :_<_[Y]1
} ukgAI<O%
pi( -A
/** D8{D[fJ;
* 每页记录数量 zxb/
*/ i[C~5}%
publicint getNum(){ ;:S&F
return num; e[u?_h
} {",MCu_V
2 gq$C"
/** {s?M*_{|
* if(num<1) num=1 ivO/;)=t
*/ hjZ}C+=O
publicvoid setNum(int num){ 9CGNn+~YI
if(num < 1) C#rc@r,F
num = 1; JE5
this.num = num; ;^
wd_
} RhI;;Y#@
psh^MX)Q
/** yZ]:y-1
* 获得总页数 4 PLk
*/ ,:Jus
publicint getPageNum(){ %\O#&=$E
return(count - 1) / num + 1; $aCd/&
} 3H\w2V
3FSqd<t;D
/** g3n'aD@'x
* 获得本页的开始编号,为 (p-1)*num+1 iq#b#PYA
*/ Y&H}xn
publicint getStart(){ 2N#$X'8
return(p - 1) * num + 1; <%}QDO8\i
} h/eR
!"Yj|Nu6
/** |!|^ v
* @return Returns the results. ! hd</_#
*/ |LG4=j.l
publicList<E> getResults(){ k;PAh>8
return results; 2A`A\19t
} ^Jp&H\gI.
ha@L94Lq
public void setResults(List<E> results){ @tohNO>
this.results = results; "|Fy+'5}
} <oKGD50#
l}^3fQXI
public String toString(){ Kemw^48ts
StringBuilder buff = new StringBuilder GY3 Wj
;rI@*An
(); nZ1zJpBmI
buff.append("{"); 5la>a}+!!h
buff.append("count:").append(count); .JX EK
buff.append(",p:").append(p); +=Jir1SLV
buff.append(",nump:").append(num); ,&PE6hn
buff.append(",results:").append VLsxdwHgb
C,V%B
(results); 7`vEe'qz
buff.append("}"); O-]mebTvw
return buff.toString(); qs\2Z@;
} 9Gy
_cTh#t ^
} 5wB =>
T#%/s?_>.
-\ZcOXpMx=