Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 F+@5C:<?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 v'e[GB0
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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 X,LD
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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 7e<c$t#H
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分页支持类: x:QgjK
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java代码: mQY_`&Jq
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package com.javaeye.common.util; kcQ'$<Mz<
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import java.util.List; %?m$`9yU
HQB(*
publicclass PaginationSupport { {Lm~r+
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publicfinalstaticint PAGESIZE = 30; ?.YOI.U^
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privateint pageSize = PAGESIZE; :hM/f
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privateList items; /RMPS.
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{
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privateint totalCount; !tp1:'KG
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privateint[] indexes = newint[0]; $H-!j%hV
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privateint startIndex = 0; AhNq/?Q Q~
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public PaginationSupport(List items, int ak;*W
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totalCount){ 4)("v-p
setPageSize(PAGESIZE); !=N"vD*
setTotalCount(totalCount); fXc m|U,ho
setItems(items); d20gf:@BM
setStartIndex(0); Yboiwy,n
} PP!SK2u"L
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public PaginationSupport(List items, int !U5Wr+83
}oNhl^JC
totalCount, int startIndex){ [h,Q Bz
setPageSize(PAGESIZE); 0D&t!$Ibf
setTotalCount(totalCount); DS)RX.k_#
setItems(items); a|?4)
setStartIndex(startIndex); VhNz8)
} Iyyh!MVF
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public PaginationSupport(List items, int lgb?)=
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totalCount, int pageSize, int startIndex){ (x3.poSt
setPageSize(pageSize); .<Zy|1
4
setTotalCount(totalCount); c.j$9=XLBG
setItems(items); ,JEFGI{
setStartIndex(startIndex); D)d~3`=#
} beu\cV3
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publicList getItems(){ HTyLJe
return items; B~_d^`
} +mp@b942*
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publicvoid setItems(List items){ X0n~-m"m
this.items = items; QI3Nc8t_2
} 1[yq0^\]M[
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publicint getPageSize(){ $t6e2=7
return pageSize; ^/U|2'$'>E
} 8f3vjK'
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publicvoid setPageSize(int pageSize){ Zib)P &
this.pageSize = pageSize; kJ Mf
} Ba/Yl
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publicint getTotalCount(){ [!U?}1YQ
return totalCount; .;*s`t
} l@ap]R
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publicvoid setTotalCount(int totalCount){ .3MIcj=p
if(totalCount > 0){ ,Y>Bex_v
this.totalCount = totalCount; <0PT"ij
int count = totalCount / ,.qMEMm
r9ww.PpNk#
pageSize; f?'JAC*
if(totalCount % pageSize > 0) k+DR]icv
count++; 'FS?a
indexes = newint[count]; :M6+p'`j
for(int i = 0; i < count; i++){ 1)[]x9]^q'
indexes = pageSize * j<)9dEM'
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i; sn?]n~z
} _`pD`7:aI^
}else{ H[='~%D
this.totalCount = 0; [mPjP%{=@
} @!8ZPiW<
} d:i;z9b@to
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publicint[] getIndexes(){ #Z<a
return indexes; 6KOlY>m]
} 1"e)5xI
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publicvoid setIndexes(int[] indexes){ -P]sRl3O;
this.indexes = indexes; &JtV'@>v
} ^tCd L@$AS
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publicint getStartIndex(){ *>+,(1Fz
return startIndex; E_bO9nRHV
} C|?o*fQ
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publicvoid setStartIndex(int startIndex){ C(K; zo*S(
if(totalCount <= 0) m]cHF.:5
this.startIndex = 0; W[}s o6
elseif(startIndex >= totalCount) &CG*)bE
this.startIndex = indexes vVgg0Y2
s$a09x
[indexes.length - 1]; iIP8`!
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elseif(startIndex < 0) *<u2:=_s
this.startIndex = 0; Qr$;AZ G
else{ "^1L'4'S
this.startIndex = indexes Y}vr>\
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[startIndex / pageSize]; uSR~@Lj ~
} NoJ`6MB
} 5T:i9h
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publicint getNextIndex(){ XZ5 /=z
int nextIndex = getStartIndex() + IEcf
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pageSize; e~"fn*"
if(nextIndex >= totalCount) E=#0I]v[
return getStartIndex(); "1-}A(X
else |#*'H*W
return nextIndex; o#hjvg
} H~E(JLcU
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publicint getPreviousIndex(){ nw6+.pOy
int previousIndex = getStartIndex() - 5A4&+rdU
51QRM32Y
pageSize; A|@_}h"WG
if(previousIndex < 0) d` [HT``
return0; gy;+_'.j
else :Pv*,qHE
return previousIndex; +d%L\^?F
} oy;K_9\
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} Dxk+P!!K
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抽象业务类 WsDM{1c
java代码: 1NcCy!+
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/** 8dlw-Q'S
* Created on 2005-7-12 @e'5E^
*/ RAp=s
package com.javaeye.common.business; L=8+_0
?Q72 ;/$
import java.io.Serializable; Q3y;$ "
import java.util.List; 3S&U!
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import org.hibernate.Criteria; TET`b7G
import org.hibernate.HibernateException; _Um d
import org.hibernate.Session; w`DW(hXJ
import org.hibernate.criterion.DetachedCriteria; bUY>st'
import org.hibernate.criterion.Projections; LE%7DW(
import _H^^y$+1
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org.springframework.orm.hibernate3.HibernateCallback; -D^}S"'
import Kb^>-[Yx
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org.springframework.orm.hibernate3.support.HibernateDaoS ZlojbL@|4
EutP\K_Y
upport; RO3oP1@B
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import com.javaeye.common.util.PaginationSupport; C-?!S
:#lIx%l
public abstract class AbstractManager extends q}FVzahv
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HibernateDaoSupport { 1lpwZ"
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privateboolean cacheQueries = false; [JaS??ig
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privateString queryCacheRegion; qSejLh6
/N-_FMl?
publicvoid setCacheQueries(boolean v<9&B94z
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cacheQueries){ 1LY8Ma]E
this.cacheQueries = cacheQueries; nJbbzQ,e
} (S ^8UV
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publicvoid setQueryCacheRegion(String wI5Yn
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queryCacheRegion){ H- p;6C<
this.queryCacheRegion = K)_WL]RJ.4
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queryCacheRegion; ,2]X}&{i
} O$ HBO
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publicvoid save(finalObject entity){ 2:LHy[{5
getHibernateTemplate().save(entity); _qWliw:0#
} Gc$gJnQio
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); D\ H/
}
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publicvoid update(finalObject entity){ "Y=+Ls(3o(
getHibernateTemplate().update(entity); >5
b/or
} BtY%r7^o
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publicvoid delete(finalObject entity){ wJlX4cT4YV
getHibernateTemplate().delete(entity); pN&c(=If
} m~'? /!!
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publicObject load(finalClass entity, :L
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sFDG)
finalSerializable id){ CD0VfA>Z
return getHibernateTemplate().load )RsM!}
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(entity, id); jn.C|9/mj
} @d&/?^dp6
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publicObject get(finalClass entity, z* <y5
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finalSerializable id){ X#w%>al
return getHibernateTemplate().get :h,`8 Di
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(entity, id); A%\tiZe
} mNYl@+:psj
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publicList findAll(finalClass entity){ _#_
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return getHibernateTemplate().find("from O3o: qly!
u? fTL2~
" + entity.getName()); #?B%Ja%
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} N:"C+a(
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publicList findByNamedQuery(finalString UMN*]_'+;b
,1/}^f6
namedQuery){ [4J6iF
return getHibernateTemplate H@uE>
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().findByNamedQuery(namedQuery); 3I 0eW%,
} *V k ^f+5
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publicList findByNamedQuery(finalString query, tD$lNh^
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finalObject parameter){ N]YtLa,t
return getHibernateTemplate J g$xO@.
_;RVe"tR#
().findByNamedQuery(query, parameter); kWj
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} ,572n[-q
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publicList findByNamedQuery(finalString query, D,ly#Nn
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finalObject[] parameters){ W0cgI9=9
return getHibernateTemplate %}>dqUyQ
+[. Yy
().findByNamedQuery(query, parameters); x6'^4y])
} ?nKF6f
/\Q*MLwD
publicList find(finalString query){ =wq;@' U
return getHibernateTemplate().find B
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(query); qO`qJ/
} vs&8wbS)
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publicList find(finalString query, finalObject 8n?kZY$,
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parameter){ 7 boJ*
return getHibernateTemplate().find 3,aN8F1;C
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(query, parameter); I]}>|
} o'%eI
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public PaginationSupport findPageByCriteria 1q.(69M
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria BC\S/5~k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /2NSZO
} '7Ig.K&
uL?vG6% ^1
public PaginationSupport findPageByCriteria 7]22"mc
W$?e<@
(final DetachedCriteria detachedCriteria, finalint $GF]/;\m
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startIndex){ _`a&9i
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return findPageByCriteria VS/;aG$&y
PK rek
(detachedCriteria, PaginationSupport.PAGESIZE, $R^lo$(
(xyS7q]m
startIndex); 8TZENRzx-|
} Lu>H`B7Q"
=7ydk"xM*
public PaginationSupport findPageByCriteria 0-2"FdeQU
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(final DetachedCriteria detachedCriteria, finalint B/eaqJ
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pageSize, :mv`\
finalint startIndex){ 8V5a%2eV
return(PaginationSupport) ;6DnId2Zh
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getHibernateTemplate().execute(new HibernateCallback(){ cBEHH4U
publicObject doInHibernate t;#Gmo
NW.XA! =E)
(Session session)throws HibernateException {
CB*/ =Y
Criteria criteria = [N|xzMe
{0's~U+@
detachedCriteria.getExecutableCriteria(session); {K7YTLWY
int totalCount = C}CKnkMMD
_ 6:ww/
((Integer) criteria.setProjection(Projections.rowCount %cW;}Y[?P
J4yt N3
()).uniqueResult()).intValue(); 3q &k
criteria.setProjection %<}=xJf>1
m)f|:MM
(null); ?y-s20Kd
List items = A0#Y, 1
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criteria.setFirstResult(startIndex).setMaxResults mtw9AoO
g"y?nF.&F
(pageSize).list(); n,KA&)/s
PaginationSupport ps = aR:<<IF\
LV.&>@*
new PaginationSupport(items, totalCount, pageSize, D@vMAW
#@_1fE
startIndex); N8+P
return ps; ,k*F`.[
} 4MX7=!E
}, true); o'qm82*
=
} vR]mSX3)?
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e
public List findAllByCriteria(final GNghB(
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DetachedCriteria detachedCriteria){ #%cR%Z
return(List) getHibernateTemplate jzrt7p*k}
'TX M{RGw
().execute(new HibernateCallback(){ .xpmp6-
publicObject doInHibernate EUwQIA2c8N
r'd/qnd
(Session session)throws HibernateException { }[,3yfiX
Criteria criteria = R`Qpd3
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detachedCriteria.getExecutableCriteria(session); c)3O/`
return criteria.list(); ]_2yiKv&
} t:9
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}, true); },6*Y*?{
} k!13=Gh
fq Y1ggL
public int getCountByCriteria(final 3'@&c?Fye
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DetachedCriteria detachedCriteria){ @"8~Y|L93
Integer count = (Integer) 8_iHVc;<
t F/nah
getHibernateTemplate().execute(new HibernateCallback(){ #>q[oie1e
publicObject doInHibernate W uf/LKj
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(Session session)throws HibernateException { BkT-m'I?
Criteria criteria = (C~dkR?
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detachedCriteria.getExecutableCriteria(session); b"P&+c
return a4u ^f5)@
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criteria.setProjection(Projections.rowCount #PH#2/[
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()).uniqueResult(); T?e9eYwS
} b_ JWnh
}, true); I{<;;;a
return count.intValue(); <_f`$z
} vXf:~G]
} xOM_R2Md
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用户在web层构造查询条件detachedCriteria,和可选的 #Gp
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Zsk?QS FE
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PaginationSupport的实例ps。 /h-6CR
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tGqQJT#mr7
ps.getItems()得到已分页好的结果集 54wM8'+
ps.getIndexes()得到分页索引的数组 4ac1m,Jlt
ps.getTotalCount()得到总结果数 FpC~1Nau
ps.getStartIndex()当前分页索引 k -]xSKG
ps.getNextIndex()下一页索引 zf7rF}
ps.getPreviousIndex()上一页索引 y&3TQ]f\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 dh?S[|='
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 `rq<jtf+
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一下代码重构了。 &*ZC0V3
@LHtt/&
我把原本我的做法也提供出来供大家讨论吧: #!Ze\fOC
?KCxrzf
首先,为了实现分页查询,我封装了一个Page类: Hz5;Ruw'
java代码: sM0c#YK?
Kv1vx*>
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/*Created on 2005-4-14*/ o6/Rx#A
package org.flyware.util.page; w. vY(s
,0FwBK
/** =E;
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* @author Joa CHg]U l
* Z3Gm
*/ ,NDxFy;d
publicclass Page { +&?'KZ+Z_v
l&$*}yCK
/** imply if the page has previous page */ H}(=?}+
privateboolean hasPrePage; `TAcZl=8
6l<1A$BQ
/** imply if the page has next page */ I=K[SY,]9
privateboolean hasNextPage; 4%%B0[Wo_O
Xv8fPP(
/** the number of every page */ uH0#rgKt
privateint everyPage; i@Vs4E[b
U* 4{"
/** the total page number */ &1oaZY w
privateint totalPage; >]^>gUmq
Io09W ^
/** the number of current page */ 98jD"*W5
privateint currentPage; .r(^h/IF
G~O" / WM
/** the begin index of the records by the current 2[XltjO
0&f\7z
query */ BZ2nDW*%
privateint beginIndex; }]tFz}E\
l~4_s/
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/** The default constructor */ G^ K*+
public Page(){ AmgWj/>
>@z d\}@W
} j,Pwket
.Dc28F~t
/** construct the page by everyPage !W0P`i<
* @param everyPage !+5C{Hs2
* */ 4Fh&V{`W
public Page(int everyPage){ `3]Rg0g&Xe
this.everyPage = everyPage; dG"K/|
} $R8>u#K!
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/** The whole constructor */ /cM 5
public Page(boolean hasPrePage, boolean hasNextPage, ^zKt{a
U2VV[e)Z!
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int everyPage, int totalPage, omNpE_
int currentPage, int beginIndex){ vuAQm}A4'g
this.hasPrePage = hasPrePage; q"P5,:W
this.hasNextPage = hasNextPage; _s2m-jm7
this.everyPage = everyPage; {(_B
this.totalPage = totalPage; H\ {E%7^h-
this.currentPage = currentPage; ~:2&/MOP?
this.beginIndex = beginIndex; C{DlcZ<
} 9e0C3+)CY
.@fK;/OuC
/** Nvi Fq
* @return kboizJp
* Returns the beginIndex. <>SR 4
*/ Zlr{L]c
publicint getBeginIndex(){ Sb'N];
return beginIndex; <'yf|N!9G
} "[#@;{@Gt
Cc@=?
/** ]d[Rf$>vu0
* @param beginIndex #4Dn@Gqh.Y
* The beginIndex to set. |if~i;VKL
*/ w:ORmR.p
publicvoid setBeginIndex(int beginIndex){ KuIBYaK,
g
this.beginIndex = beginIndex; <j{0!J@:
} XulaPq
lb-S0plw
/** y{@P1{
* @return )!'Fa_$ e
* Returns the currentPage. ,:Rft
*/ w906aV*s
publicint getCurrentPage(){ tZdwy> ;
return currentPage; /#:Rd^
} Lhl$w'r
cxAViWsf
/** TP{>O%b
* @param currentPage S`ax*`
* The currentPage to set. 'bZMh9|
*/ YgO aZqN
publicvoid setCurrentPage(int currentPage){ *?EO n -
this.currentPage = currentPage; fG X1y
} \Oi5=,
1M7\:te*
/** x>U1t!'
* @return EC^Ev|PB\u
* Returns the everyPage. b24NL'jm
*/ .jvSAV5B
publicint getEveryPage(){ 3'?h;`v\Lo
return everyPage; om XBnzT
} )j{WeG7L
6T R8D\
/** 83{x"G3>
* @param everyPage 'LJ %.DJ
* The everyPage to set. IyrZez
*/ +io;K]C
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; V}vl2o
} k7:GS,7
+^/Nil
/** R88(dEK
* @return ,maAw}=
* Returns the hasNextPage. "[%;B0J
*/
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publicboolean getHasNextPage(){ u5u0*c
return hasNextPage; B, QC-Tn
} A8_\2'b
kS@9c _3S
/** I>A^5nk
* @param hasNextPage `f\5p+!<7R
* The hasNextPage to set. =XZF.ur
*/ R=][>\7]}
publicvoid setHasNextPage(boolean hasNextPage){ Qh)|FQ[s$r
this.hasNextPage = hasNextPage; g`%ED0aR
} Zp/qs
z(]
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/** O!#L#u53
* @return \SYPu,ZT
* Returns the hasPrePage. <7vI h0
*/ ",MK'\E
publicboolean getHasPrePage(){ aX>4Tw
return hasPrePage; xTa4.ZXg
} "o\6k"_c>
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/** Gk{
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* @param hasPrePage wc<2Uc
* The hasPrePage to set. t-v^-#
*/ LV}UBao5n
publicvoid setHasPrePage(boolean hasPrePage){ OhSt6&+
this.hasPrePage = hasPrePage; |% M{kA-
} sYAG,r>h
bqZ?uvc3
/** O4 +SD
* @return Returns the totalPage. Ff)~clIK '
* H3
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*/ C$N4
publicint getTotalPage(){ [oQ`HX1g
return totalPage; V\iIvBpWg
} q;1VF;<"vH
oiTMP`Y
/** )z?&"I
* @param totalPage 902!M65[rG
* The totalPage to set. +Op%,,Db
*/ >)AE|j`
publicvoid setTotalPage(int totalPage){ vSyi}5D
this.totalPage = totalPage; NPB ,q& Th
} 8I5 VrT
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p
} wu&|~@_s@
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 c~^]jqid]
aIzp\$NWVK
个PageUtil,负责对Page对象进行构造: Xa? 6#
java代码: )+jK0E1
g9FVb7In_
Ov~S2?E8
/*Created on 2005-4-14*/ Rk437vQD,
package org.flyware.util.page; 2;Y@3d:z
yZj}EBa
import org.apache.commons.logging.Log; ;qT!fuN;
import org.apache.commons.logging.LogFactory; (!XYH@Mz<w
.J<qfQ
/** w]o:c(x@
* @author Joa ^| FVc48{
* s60:0 >
*/ NE=#5?6%g7
publicclass PageUtil { r2E>sHw
6*(h9!_T1
privatestaticfinal Log logger = LogFactory.getLog vUo.BA#;.b
v2Qc}o
(PageUtil.class); a.Rp#}f
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/** `aO@N(
* Use the origin page to create a new page RF,=bOr19
* @param page "a0u-}/D
* @param totalRecords ~kSnXJv
* @return V(''p{
*/ ig.6[5a\
publicstatic Page createPage(Page page, int .^)C:XiW
+AgkPMy
totalRecords){ !"Oj$c
-
return createPage(page.getEveryPage(), ^?K?\
2d>d(^
page.getCurrentPage(), totalRecords); :YRzI(4J
} !5E%W[
XW&8T"q7
/** Q[ 9rA
* the basic page utils not including exception ,/w852|ub
g'}`FvADi
handler u]]5p[|S
* @param everyPage [)J49
* @param currentPage Vlp*'2VO
* @param totalRecords L?D~~Jb
* @return page XTi0,e]5{u
*/ $3]E8t
publicstatic Page createPage(int everyPage, int "zeJ4f
sjkKaid
currentPage, int totalRecords){ 02# b:
everyPage = getEveryPage(everyPage); FB=
currentPage = getCurrentPage(currentPage); 3"^)bGe
int beginIndex = getBeginIndex(everyPage, `!Ge"JB6
LDi ezi
currentPage); *OGXu07 !
int totalPage = getTotalPage(everyPage, Gwrx)Mq
;@7#w
totalRecords); p^zEfLTU
boolean hasNextPage = hasNextPage(currentPage, %<ptkZK#
^7s6J{<
totalPage); %)6:eIS
boolean hasPrePage = hasPrePage(currentPage); zfr (dQ
?%za:{
returnnew Page(hasPrePage, hasNextPage, Qq FfR#
everyPage, totalPage, xV n]m9i
currentPage, Cs1%g
Nz>E#.++
beginIndex); a`@<Z sR
} jB/q1vFO
X_tW#`
privatestaticint getEveryPage(int everyPage){ o+)LcoPu
return everyPage == 0 ? 10 : everyPage; kq1M<lk
} |q!2i
N5w]2xz!
privatestaticint getCurrentPage(int currentPage){ R/Dy05nloe
return currentPage == 0 ? 1 : currentPage; (g)lv)4P
} 7AtXG^lK
#Zavdkw=d
privatestaticint getBeginIndex(int everyPage, int /4-eoTxy
ZAo)_za&mH
currentPage){ Y%?!AmER
return(currentPage - 1) * everyPage; $ Pb[c%'
} s!o<Pd yJK
X $9D0;L
privatestaticint getTotalPage(int everyPage, int E~Up\f
aIt
0;D
totalRecords){ "za*$DU
int totalPage = 0; k0e|8g X
K`_E>k
if(totalRecords % everyPage == 0) e2h k
totalPage = totalRecords / everyPage; C#?d=x
else b1>$sPJ+
totalPage = totalRecords / everyPage + 1 ; c;~Llj
P
C O%O<_C
return totalPage; 9
K /
} %wjU^Urya
Jn:GA@[I
privatestaticboolean hasPrePage(int currentPage){ a+a%}76N
return currentPage == 1 ? false : true; >A'!T'"~
} : .w'gU_
]kplb0`
privatestaticboolean hasNextPage(int currentPage, (27F
VY&9kN
int totalPage){ $evuPm8G
return currentPage == totalPage || totalPage == tSXjp
O*n%2Mam
0 ? false : true; @n;YF5
} 1d@^,7MF-
ah6F^Kpl{
>'1Q"$;
} +!V%Q
(zLIv9$
]'ApOp
CD<u@l,1
2,e|,N"zN
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。 |xgCV@
k;:u| s8NS
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 36Z`.E>~L
(b2^d
做法如下: pu)9"Ad[ G
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 l<K.!z<-:8
h}%M
的信息,和一个结果集List: "KTnX#<0
java代码: {FmFu$z+[
c%3
@J+z
53&xTcv}x
/*Created on 2005-6-13*/ zUgkY`]:BJ
package com.adt.bo; G-i_s6Wu
Xiedg y
import java.util.List; n_Hnk4
]aW.b_7<9
import org.flyware.util.page.Page; [MXXY
w*ktx{
/** &fy8,}
* @author Joa NizJq*V>
*/ .-26 N6S
publicclass Result { dSOn\+
S+xGHi)
private Page page; ?
A#z~;X@
<@j
private List content; BHE =Zo
np>!lF:
/** dvWlx]'
* The default constructor __n"DLW
*/ (X7yNIPfA
public Result(){ HY| SLk/E
super(); [[DFEvOEh
} 3@ukkO)
`V_/Cz_}D
/** :3*oAh8|
* The constructor using fields !skWe~/
* ]~M{@h!<
* @param page 257;@;
* @param content m1;
<T@
*/ k 5r*?Os
public Result(Page page, List content){ b2f2WY |z>
this.page = page; VM|)\?Q
this.content = content; Fl>j5[kLZ
} ,F9wc<V8
qq%_ksQ
/** ^[z\KmUqt
* @return Returns the content. r$eL-jQmn
*/ |w]i$`3'I
publicList getContent(){ XBt0Ez
return content; 5h^qtK
} (9_e>2_
F%$Ws>l
/** 00wH#_fm
* @return Returns the page. uOUw8
*/ 2}\sj'0&
public Page getPage(){ ZS>/ 5
return page; n?fC_dy
} I%*Zj,>
I}0-
/** I,?LZ_pK
* @param content ][qA@3^Tw
* The content to set. Ip\g^ia
*/ |-Klh
public void setContent(List content){ l>P~M50D?{
this.content = content; { 3P!b|V>
} 9JeGjkG,
*<5lx[:4/x
/** iZ;jn8
* @param page sh3}0u+
* The page to set. Ec/+ 9H6g
*/ 'N/%SRk
publicvoid setPage(Page page){ JkEQ@x
this.page = page; 8>+eGz|
} dM.Ow!j
} $4)guG)
@,$HqJ
ky"7 ^
m{Xf_rQ
w
5d;K.O
2. 编写业务逻辑接口,并实现它(UserManager, d-&dA_?
52Ffle8
UserManagerImpl) $}o,7xAn
java代码: yG_.|%e
?&^l8gE
~i {)J
/*Created on 2005-7-15*/ &G,v*5N8$K
package com.adt.service; L7'n<$F
Jq@LZ2^
import net.sf.hibernate.HibernateException; .qP
zd(<T7
2a}_|#*
import org.flyware.util.page.Page; @WUCv7U
~z"->.u
import com.adt.bo.Result; x6P^IkL:
2!`Z3>Oa
/** $S=OmdgR
* @author Joa 8[XNFFUZs
*/ TQfY%GKg(
publicinterface UserManager { p{u}t!`!d
E_*T0&P.P
public Result listUser(Page page)throws ,
>6X_XJQ
}trMQ
HibernateException; ld0WZj
}Q*ec/^{f
} sbb{VV`I
FpYoCyD}
I!%@|[ Ow
&$
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n6dg
java代码: a#@opUn-
|LhuZ_;1xo
$x<-PN
/*Created on 2005-7-15*/ {GY$J<5=
package com.adt.service.impl; RAa1KOxZX
-#hl&^u$
import java.util.List; ttxOP
hTqJDP"&F
import net.sf.hibernate.HibernateException; +%^xz
1m
EkPSG&6RZ
import org.flyware.util.page.Page; Xp@OIn
import org.flyware.util.page.PageUtil; .-
o,_eg1f
p_5+L@%Gb
import com.adt.bo.Result; ={d\zjI$
import com.adt.dao.UserDAO; tp0*W
_<4
import com.adt.exception.ObjectNotFoundException; =Ih_[$1dw
import com.adt.service.UserManager; oWT0WS
Z%{2/mQ
/** ' 1IH^<b
* @author Joa :DP{YL|x
*/ QX/`s3N
publicclass UserManagerImpl implements UserManager { Y"U&3e,
L.(k8eX
private UserDAO userDAO; Z$gY}Bz
qz):YHxT]n
/** q2Dg~et
* @param userDAO The userDAO to set. /_HL&|N_5
*/ pgarGaeq
publicvoid setUserDAO(UserDAO userDAO){ LPClE5
this.userDAO = userDAO; QUO?q+
}
ekXHfA!i%
:2+:(^l
/* (non-Javadoc) a$-ax[:\sm
* @see com.adt.service.UserManager#listUser _t7A'`Dh]
SJmri]4K
(org.flyware.util.page.Page) 23m+"4t
*/ }r[BME
public Result listUser(Page page)throws W*#/@/5
jLU)S)
HibernateException, ObjectNotFoundException { xFh}%mwpt[
int totalRecords = userDAO.getUserCount(); a7R7Ks|q
if(totalRecords == 0) [&&4lKC}u
throw new ObjectNotFoundException auU{Iy
:JmNy<
("userNotExist"); <7+.5iB3
page = PageUtil.createPage(page, totalRecords); ewR0e.g
List users = userDAO.getUserByPage(page); bL<cgtz7)
returnnew Result(page, users); sP#5l @
} *HUqW}_r
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} USY^
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`3Y+:!q
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7(-<x@ e
`K.yE0^i
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 o>h>#!e
G5Nub9_*X
询,接下来编写UserDAO的代码: _;9)^})$
3. UserDAO 和 UserDAOImpl: z'o+3zq^
java代码: O@VmV>m
Ki2_Nh>tM
j
yE+?4w;
/*Created on 2005-7-15*/ |b'AWI81D
package com.adt.dao; 8dNJZoV
TOs|f8ay
import java.util.List; b?l\QMvi
G4~J+5m k
import org.flyware.util.page.Page; GOjri
o<;"+ @v
import net.sf.hibernate.HibernateException; U-d&q>_@A
aE}u5L$#
/** {Ffr l(*
* @author Joa `O F\f
*/ YR>x h2< 9
publicinterface UserDAO extends BaseDAO { fQ@["b
o5d)v)Rx=
publicList getUserByName(String name)throws wS*UXF&f
bk|>a=o3
HibernateException; I[/u5V_b'
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publicint getUserCount()throws HibernateException; W# $rC<Jh]
asb")NfIm
publicList getUserByPage(Page page)throws "Y6f.rB
V_:/#G]jeG
HibernateException; &F)lvtt|
L=>N#QR7
} *Co+UJjT
o_S8fHqjt
b^1!_1c
&j$k58mX
o{/D:B
java代码: %%#zO
Z
5E]I
%NuS!v>
/*Created on 2005-7-15*/ MZ.Jkf(
package com.adt.dao.impl; A-kI_&g\Og
y~w$>7U.
import java.util.List; %~@}wHMB
z\a#"2(G.
import org.flyware.util.page.Page; YRl2e`&jt
Xv6s,< #\
import net.sf.hibernate.HibernateException; 5_PD?lg
import net.sf.hibernate.Query; KpWQ;3D2
g]S.u8K8m
import com.adt.dao.UserDAO; DY%E&Vd:h
Q[ IaA"
/** *ZRQ4i[+
* @author Joa ~*RNJ
*/ h
c"n?
public class UserDAOImpl extends BaseDAOHibernateImpl 3OTSLF/
#'8E%4
implements UserDAO { \;~>AL*
-LF^u;s8&S
/* (non-Javadoc) Tg[+K+ b
* @see com.adt.dao.UserDAO#getUserByName k;]&`c^5
0@>3fR
(java.lang.String) 9d
v+u6)
*/ z5?xmffB
publicList getUserByName(String name)throws U_+>4zdm
XWk^$ "
HibernateException { Xln'~5~)
String querySentence = "FROM user in class \ /o`CV{O
ie5"
com.adt.po.User WHERE user.name=:name"; (%".=x-
Query query = getSession().createQuery ?>e-6*.
lUDzfJ}3
(querySentence); 0h* AtZv_
query.setParameter("name", name); <~]s+"oVc
return query.list(); 3]T2Zp&;
} SOd(& >
hD"Tjd` P
/* (non-Javadoc) 1 #_R`(C{
* @see com.adt.dao.UserDAO#getUserCount() /.vB /{2
*/ N[Fz6,ZG _
publicint getUserCount()throws HibernateException { 3ILEc:<0J
int count = 0; ZT!DTb
B
String querySentence = "SELECT count(*) FROM +Oo>V~
x.!%'{+{
user in class com.adt.po.User"; `6'fX[j5
Query query = getSession().createQuery ^;M!u8 [
e4t'3So
(querySentence); b}Jcj
count = ((Integer)query.iterate().next r@ ]{`qA
A+AqlM+$i
()).intValue(); 94Are<
return count; U:p<pTnMR
} TRa|}JaI"
B#8!8
/* (non-Javadoc) qWdL|8
* @see com.adt.dao.UserDAO#getUserByPage [W`
_`
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(org.flyware.util.page.Page) /S%{`F=
*/ C"K(-/
publicList getUserByPage(Page page)throws v#F.FK
XK>B mq/]
HibernateException { 4~DoqT
String querySentence = "FROM user in class N|wI=To
%kUIIHV}
com.adt.po.User"; //xxSk
Query query = getSession().createQuery |?g k%g
(wkeo{lx
(querySentence); dG\dGSZ\h
query.setFirstResult(page.getBeginIndex()) BTqY_9
.setMaxResults(page.getEveryPage()); yi
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return query.list(); aVEg%8
} ;BsyN[bF
w!7Hl9BW
} 2+50ezsId
!A qSG-
cE'MSB
pwr,rAJ}$j
v="i0lL_
至此,一个完整的分页程序完成。前台的只需要调用 Zgd|
J T7
|4UW.dGHPo
userManager.listUser(page)即可得到一个Page对象和结果集对象 C0J/FFBQ ^
p{gJVP#l'Z
的综合体,而传入的参数page对象则可以由前台传入,如果用 U*b1yxt
.}C
pX
webwork,甚至可以直接在配置文件中指定。 U,\3 !D0jt
Q#i[Y?$L
下面给出一个webwork调用示例: DHQavHqbZ
java代码: edD1 9A
bkTk:-L5:
[7oU =
/*Created on 2005-6-17*/ ]hRCB=G
package com.adt.action.user; qXcHf6
Jsde+G,N
import java.util.List; R1)v;^B|)
:+06M@
import org.apache.commons.logging.Log; [f 4Nq \i
import org.apache.commons.logging.LogFactory; `ZhDoLpH<
import org.flyware.util.page.Page; 7b7@"Zw*
8Th{(J_
import com.adt.bo.Result; 5o- WA1
import com.adt.service.UserService; 7,X5]U&A<x
import com.opensymphony.xwork.Action; s|FfBG
bLuAe
EA
/** WKek^TW4HE
* @author Joa u 6A!Sw
*/ j\@Ht~G
publicclass ListUser implementsAction{ k/srT<
_P,3~ ;
privatestaticfinal Log logger = LogFactory.getLog xA/Ein0
j
S~Wcu
(ListUser.class); }&!fT\4
-k(bM:
private UserService userService; GI']&{
v"-@'qN'
private Page page; <a_ytSoG1
I54`}Npp
privateList users; iW oe
Vh=10Et
/* cc37(=oKL
* (non-Javadoc) {-a8^IK,
* ,%Sf,h?"^
* @see com.opensymphony.xwork.Action#execute()
vf}.)
*/ =r=?N\7I
publicString execute()throwsException{ ?y"=jn
Result result = userService.listUser(page); ;l4epN
page = result.getPage(); rs`"Kz`(
users = result.getContent(); (m:ktd=x
return SUCCESS; B bP&-c
} pQ2'0u5w5
U}hQVpP#
/** N#C,q&;
* @return Returns the page. pT ]: TRPS
*/ t:$^iUrx
public Page getPage(){ Ct@O S227x
return page; Lgr(j60s
} ;fiH=_{us
9IfeaoZZ4q
/** |
6/ # H*
* @return Returns the users. 4 s&9A/&pC
*/ $OGTHJA
publicList getUsers(){ $<DcbJW
return users; m6wrG`-di
}
{@E(p4W
S~GL_#a
/** >tGl7Ov
* @param page &-R(u}m-F
* The page to set. mqrV:3}
*/
7j,u&%om
publicvoid setPage(Page page){ 7^bde<0
this.page = page; J) I|Xot
} u"hv
_ml
X7."hGu@
/** i`st'\I
* @param users Z~[EZgIg
* The users to set. lJ>OuSd
*/ e]5
n4"]D)
publicvoid setUsers(List users){ 25R6>CXsi
this.users = users; %Bxp
!Bj
} J!+)v
'cgB$:T}.,
/** T#OrsJdu
* @param userService <4Ev3z*;Z
* The userService to set. `514HgR
*/ OK8|w]-A
publicvoid setUserService(UserService userService){ 2WF7^$^:
this.userService = userService; o W<Z8s;p
} ^E]Xq]vd"
} e<Bwduy
og$%`o:{
x9Oo.[
hAi`2GP.
CO5>Q o
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, -5X*y4#
a]]>(Txc
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 myq:~^L
;
=CqZ $
么只需要: e09('SON(
java代码: $_5a1Lq1
D^-6=@<3KD
[Z-S0
<?xml version="1.0"?> a@?2T,$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork L!qXt(`
q{RH/. l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $C.;GU EQ
@hV F}ybp
1.0.dtd"> GeydVT-
g#}a?kTM@
<xwork> T*3>LY+bb
#Y>os3]
<package name="user" extends="webwork- I7C*P~32{n
N"k
IQe*}1
interceptors"> IN!,|)8s
%p d-{KR
<!-- The default interceptor stack name @a]O(S>Ub
t^')ST
--> !Zi_4 .(4
<default-interceptor-ref Z]^Ooy[pb
UB9n7L(@c
name="myDefaultWebStack"/> Ms61FmA4
ZvVrbj&
<action name="listUser" {vf4l4J(
^1 U<,<
class="com.adt.action.user.ListUser"> OL0W'C9oA
<param ibj3i7G?
]-+%]'
name="page.everyPage">10</param> Ho!dtEs
<result "I}]]?y
+=o?&
name="success">/user/user_list.jsp</result> -1z<,IN+
</action> )}|b6{{<
vw5f|Q92
</package> l =`?Im
GYJ
lX
</xwork> &ZR} Z7E*=
V'Z Z4og
V;-$k@$b.
9\J6G8b>|I
@o/126(k
*=
;M',nx
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 _X/`7!f
7FBaN7l
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 r0'6\MS13
:GBM`f@
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 m]"13E0*x
}j\_XaB
Tj3xK%K_r3
a 9H^e<g
;jZfVRl
我写的一个用于分页的类,用了泛型了,hoho E(p*B8d
:d{-"RAG"
java代码: !M*$pQi}
XI/LVP,.
kaG@T,pH(
package com.intokr.util; c8<qn+=%?
=_)yV0
import java.util.List; \LbBK ~l-I
.KeZZLH
/** i"Z
* 用于分页的类<br> z7$,m#tw
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Hsl0|jy(/
* r&0IhE
* @version 0.01 O*dtVX
* @author cheng I|eYeJ3
*/ Yb?L:,a(I
public class Paginator<E> { zho$g9*
privateint count = 0; // 总记录数 ,)beK*Iw
privateint p = 1; // 页编号 8?z7!k]
privateint num = 20; // 每页的记录数 Eb.k:8?Tn
privateList<E> results = null; // 结果 @;1Ym\zc
D\CjR6DE
/** u+_6V
* 结果总数 6aq=h`Y
*/ [,?5}'we
publicint getCount(){ *^=zQ~
return count; E,wOWs*
} ,2MLYW,
?#]wxH,
publicvoid setCount(int count){ hwj:$mR
this.count = count; [PP&}.k4"
} vOV$H le
NG\g_^.M
/** -qNun3
* 本结果所在的页码,从1开始 fnZ?YzLI
* 2Q81#i'Cm
* @return Returns the pageNo. %}/ |/=
*/ tmVGJ+gz
publicint getP(){ v3I-i|L<)
return p; P g.j]
} Yk @/+PE
6t!PHA
/** Nay&cOz
* if(p<=0) p=1 t,,W{M|E(
* 6U(MHxY
* @param p vp2s)W8W
*/ , SB5"
publicvoid setP(int p){ =,w(D~ps
if(p <= 0) EZb_8<DH
p = 1; efUa[XO
this.p = p; {,Z-GJ
} @{LD_>R
$z
\H*
/** )8@|+'q
* 每页记录数量 O+ghw1/
*/ <4%cKW0
publicint getNum(){ .d;|iwl
return num; }P*x/z~
} kC8M2 |L
tcD DX'S
/** 6i7+.#s
* if(num<1) num=1 dh0n B
*/ ,C;%AS/
publicvoid setNum(int num){ W<tw],M-#
if(num < 1) u?%FD~l:uU
num = 1; /+JHnedK
this.num = num; a,`f`;\7N%
} W:S?_JM
zkb[u"
/** 'MK"*W8QRM
* 获得总页数 ?&_u$Nn
*/ sp8P[W1a
publicint getPageNum(){ rF\L}& Sw
return(count - 1) / num + 1; S!6 ? b5
} 9?38/2kX4
:c}"a(|
/** e754g(|>b
* 获得本页的开始编号,为 (p-1)*num+1 O]VHX![Y$
*/
.u3Z*+
publicint getStart(){ peD7X:K\s
return(p - 1) * num + 1; ^SvGSxi
} /Dj-@7.C/
-J]j=
/** G;he:Bf
* @return Returns the results. h,@tfd U^
*/ 5lrjM^E|
publicList<E> getResults(){ H63?Erh>a
return results; F1GFn|OA
} p:?h)'bA<
./i5VBP5
public void setResults(List<E> results){ `NB6Of*/
this.results = results; w0&|8y
} Y{D?&x%yq
_h^er+d!_
public String toString(){ ';zS0Yk
StringBuilder buff = new StringBuilder # ~(lY}
%@MO5#)NI
(); Lu5lpeSQ
buff.append("{"); *|({(aZ
buff.append("count:").append(count); }F4%5go
buff.append(",p:").append(p); ;|r<mT/,
buff.append(",nump:").append(num); =HHtLW.|,
buff.append(",results:").append k, >*.Yoh
(MzThGJK_
(results); EV[ BB;eb
buff.append("}"); %v)+]Ds{
return buff.toString(); {&uN q^Ch
} ap wA
F#KUu3;B
} WGA"e
Nz;f| 2h
L2>
)HG