Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2Lekckgv
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UUf1T@-
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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 D2:a
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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 Cn;H@!8<s
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分页支持类: E'S;4B5?
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java代码: liw 9:@+V
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package com.javaeye.common.util; /Np"J
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import java.util.List; 8^/Ek<Qb|
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publicclass PaginationSupport { 6a]f&={E
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publicfinalstaticint PAGESIZE = 30; K'5sn|)
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privateint pageSize = PAGESIZE; v#%>uLl
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privateList items; AzO3 (1:
Na 9l#
privateint totalCount; FHNuMdFn
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0
privateint[] indexes = newint[0]; M |Q
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privateint startIndex = 0; v8[ek@
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public PaginationSupport(List items, int %Di7u- x
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totalCount){ _h=<_Z
setPageSize(PAGESIZE); AV[P QI
setTotalCount(totalCount); JIbzh?$aD
setItems(items); XJlDiBs9=Q
setStartIndex(0); b8{h[YJL2
} b!5tFX;J
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public PaginationSupport(List items, int {`Fx~w;i
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totalCount, int startIndex){ *VC4s`<
setPageSize(PAGESIZE); 4`!
setTotalCount(totalCount); ]i,Mq
setItems(items); 9HNh*Gc=
setStartIndex(startIndex); 1|~#028
} 5lHN8k=mm2
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public PaginationSupport(List items, int H&yFSz}6a
\|pK Z6*s
totalCount, int pageSize, int startIndex){ wO_pcNYZ8
setPageSize(pageSize); A.$VM#
setTotalCount(totalCount); 1_j<%1{sZ
setItems(items); Tu=eQS|'
setStartIndex(startIndex); @[>+Dzn[6
} x)#<.DX
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publicList getItems(){ ttbQergS
return items; M~z(a3@[V
} }lC64;yo
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publicvoid setItems(List items){ Y6f+__O
this.items = items; APQQ:'>N4~
} wwK~H
#}t1
publicint getPageSize(){ X$uz=)
return pageSize; N1+4bR
} r>Qyc
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publicvoid setPageSize(int pageSize){ gB{]yA"('
this.pageSize = pageSize; ^Z-.[Y
} xu"94y+
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publicint getTotalCount(){ Wp7@
return totalCount; {?
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} D,GPn%Wqi
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publicvoid setTotalCount(int totalCount){ #.MIW*==
if(totalCount > 0){ TRySl5jx@
this.totalCount = totalCount; :_fjml/
int count = totalCount / p;n3`aVh
zO).<xIq+
pageSize; n $O.>
if(totalCount % pageSize > 0) mV**9-"
count++; -n=$[-w
indexes = newint[count]; "u Of~e"
for(int i = 0; i < count; i++){ c>u>Pi;Z
indexes = pageSize * eHR&N.2
<i:*p1#Bm
i; Y @XkqvX
} B{OW}D$P#
}else{ V`R)#G>IH%
this.totalCount = 0; "5o;z@(
} RFZU}.*K$
} Pghva*&
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publicint[] getIndexes(){ 9*-pden
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return indexes; M\\e e3Ih
} +
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publicvoid setIndexes(int[] indexes){ eN<>#:`
this.indexes = indexes; 7,W]zKH
} ^(dGO)/
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publicint getStartIndex(){ &AQg'|
return startIndex; qEK4I}Q-=
} /`4v"f0V
>YJ8u{Z{o
publicvoid setStartIndex(int startIndex){ teq^xTUF[
if(totalCount <= 0) u|m[(-`
this.startIndex = 0; o;M.Rt\A
elseif(startIndex >= totalCount) ]=?X*,'
this.startIndex = indexes PS_3Oq)
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[indexes.length - 1]; l5ZADK4
elseif(startIndex < 0) 097Fvt=#
this.startIndex = 0; "4Lg8qm
else{ JAGi""3HG
this.startIndex = indexes
^MWEfPt
[ 5CS}FB
[startIndex / pageSize]; :"OZc7
~
} _KSfP7VU
} A6?qIy
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publicint getNextIndex(){ njy~
int nextIndex = getStartIndex() + };|!Lhl+
*<`7|BH 3
pageSize; TRs[ ~K)n
if(nextIndex >= totalCount) y'J:?!S,Yu
return getStartIndex(); (xk.NZnF
else `DgaO-Dg3
return nextIndex; 1&X}1
} u#a%(
ysSjc
publicint getPreviousIndex(){ 38V $ <w
int previousIndex = getStartIndex() - fbh6Ls/
olD@W
UB
pageSize; vh9kwJyT
if(previousIndex < 0) b{~fVil$y
return0; Gt^|+[gD
else Wphe%Of
return previousIndex; ewb*?In
} 7.wR"1p#
wFK:Dp_^
} MuDFdbtR
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抽象业务类 y;,=ajrF
java代码: Zw;$(="
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/** ~/^y.SsWM
* Created on 2005-7-12 /[\6oa
*/ <u6c2!I{
package com.javaeye.common.business; MZCL:#
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import java.io.Serializable; ?60>'Xjj
import java.util.List; ,bB( 24LD
fp.!VOy
import org.hibernate.Criteria; tP}Xhn`
import org.hibernate.HibernateException; Xtuhc dzu[
import org.hibernate.Session; Hnfvo*6d.e
import org.hibernate.criterion.DetachedCriteria; I#i?**
import org.hibernate.criterion.Projections; e%PCe9
import *hv=~A
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org.springframework.orm.hibernate3.HibernateCallback; r/UYC"K3
import R'S c
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org.springframework.orm.hibernate3.support.HibernateDaoS Cr'
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upport; jK3giT
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import com.javaeye.common.util.PaginationSupport; |?\gEY-Se
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public abstract class AbstractManager extends 9k+N3vA
v57N^DR{
HibernateDaoSupport { mZ`1JO9
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privateboolean cacheQueries = false; gb.f%rlZ`
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privateString queryCacheRegion; TFBYY{Y
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publicvoid setCacheQueries(boolean hmc\|IF`
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cacheQueries){ R
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this.cacheQueries = cacheQueries; }BA9Ka#%
} /uK)rG
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publicvoid setQueryCacheRegion(String KjO-0VMN3
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queryCacheRegion){ *6NO-T; -
this.queryCacheRegion = '
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queryCacheRegion; v2IEJ
} 5iP8D<;o5
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publicvoid save(finalObject entity){ lo"j )Zt
getHibernateTemplate().save(entity); uQ{=o]sy
} \|v `l{
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publicvoid persist(finalObject entity){ Xwn3+tSIa
getHibernateTemplate().save(entity); !A~d[</]m
} F;pTXt}?5
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publicvoid update(finalObject entity){ U$A/bEhw
getHibernateTemplate().update(entity); x:p}w[WM
} +H41]W6
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publicvoid delete(finalObject entity){ ,oBlJvm
getHibernateTemplate().delete(entity); $"/UK3|d
} DLU[<!C
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publicObject load(finalClass entity, 5(423"(y
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finalSerializable id){ Tj Mb>w9
return getHibernateTemplate().load DG3[^B
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(entity, id); _8al
} +-U@0&Y3M
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publicObject get(finalClass entity, a|U}Ammr
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finalSerializable id){ ]y.Rg{iv
return getHibernateTemplate().get wjL|Z8
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(entity, id); 4 ^4d9?c
} yDzdE;
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publicList findAll(finalClass entity){ tL1P<1j_
return getHibernateTemplate().find("from vuXS/ d
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" + entity.getName()); p7s@%scp
} >o#ERNf
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publicList findByNamedQuery(finalString ~xw5\Y^
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namedQuery){ 4b]_
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return getHibernateTemplate #hpIyy%n
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().findByNamedQuery(namedQuery); |P>|D+I0
} U{"f.Z:Ydo
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publicList findByNamedQuery(finalString query, )9MrdVNv
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finalObject parameter){ Mxo6fn6-46
return getHibernateTemplate h!v/s=8c
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().findByNamedQuery(query, parameter); r?\|f:M3
} B=r0?%DX"1
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publicList findByNamedQuery(finalString query, lw s(/a*c
{$0&R$v3
finalObject[] parameters){ sllzno2bU
return getHibernateTemplate ]dq5hkjpU
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().findByNamedQuery(query, parameters); @^'$r&M
} wDMjk2YN
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publicList find(finalString query){ #\LZ;&T'N
return getHibernateTemplate().find "NKf0F
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(query); x)3~il5
} j AQU~Ol_
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publicList find(finalString query, finalObject 7u::5 W-q
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parameter){ G,=F<TnI'
return getHibernateTemplate().find Hng!'
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(query, parameter); U-eI\Lu
} @ ICbKg:
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public PaginationSupport findPageByCriteria Fom>'g*
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(final DetachedCriteria detachedCriteria){ I(n }<)eF
return findPageByCriteria p-,Iio+
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); mL$f[
} v77fQ0w3
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public PaginationSupport findPageByCriteria 'l|R5
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(final DetachedCriteria detachedCriteria, finalint -TTs.O8P|<
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startIndex){ r1;e 0\?`
return findPageByCriteria Yy hny[fa9
0cFn{q'u
(detachedCriteria, PaginationSupport.PAGESIZE, ETO$9}x[
@(>XOj?+
startIndex); > ws!5q
} @cIgxp
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public PaginationSupport findPageByCriteria O |WbFf
pv&^D,H,
(final DetachedCriteria detachedCriteria, finalint _f|/*.
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pageSize, Z(;AyTXA
finalint startIndex){ ;Xu22fKh
return(PaginationSupport) P6YQK+
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getHibernateTemplate().execute(new HibernateCallback(){ \(fq8AL?
publicObject doInHibernate Xu#:Fe}:
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(Session session)throws HibernateException { Xm|ib%no
Criteria criteria = n P1GW6Pu
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detachedCriteria.getExecutableCriteria(session); Y@%`ZPJ
int totalCount = iP#=:HZu;
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((Integer) criteria.setProjection(Projections.rowCount W#{la`#Bu
h/K@IAd
()).uniqueResult()).intValue(); +c) TDH
criteria.setProjection #9:2s$O[x
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(null); =EpJZt
List items = 0hwj\{"
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criteria.setFirstResult(startIndex).setMaxResults +s~.A_7)
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(pageSize).list(); f4"4ZVcr
PaginationSupport ps = pj;
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new PaginationSupport(items, totalCount, pageSize, k ZxW"2
k>5 O`Y:
startIndex); rwgsXS8W6
return ps; ,Sg33N?
} YeyGN
}, true); mmP U
} L/i(KF{
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public List findAllByCriteria(final D:JS)+]
/:p8I6;
DetachedCriteria detachedCriteria){ wkBL=a
return(List) getHibernateTemplate 3?`"
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().execute(new HibernateCallback(){ wz=z?AZW
publicObject doInHibernate P1V1as
;#/0b{XFj
(Session session)throws HibernateException { V LdB_r3lQ
Criteria criteria = IzUo0D*@
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detachedCriteria.getExecutableCriteria(session); *aRX \TnN
return criteria.list(); <
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} d#>y }H9
}, true); *7RvHHf
} CT*,<l-D
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public int getCountByCriteria(final <kbyZXV@K
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DetachedCriteria detachedCriteria){ }l;Lxb2`
Integer count = (Integer) ~pz FZ7n4
}ZzLs/v%X
getHibernateTemplate().execute(new HibernateCallback(){ u|fXP)>.
publicObject doInHibernate u
#~;&D*q
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(Session session)throws HibernateException { RH[+1z8
Criteria criteria = JE;+T[I
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detachedCriteria.getExecutableCriteria(session); H l<$a"K7\
return 4!%F\c46
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criteria.setProjection(Projections.rowCount zwr\:Hu4
DWm SC}{.
()).uniqueResult(); n:4uA`Vg
} >]?H`>4(
}, true); |W7rr1]~S
return count.intValue(); _0(7GE13p
}
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} -JV~[-,
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用户在web层构造查询条件detachedCriteria,和可选的 FxRXPt
FK
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |d}MxS`^
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PaginationSupport的实例ps。 bx}fj#J]En
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ps.getItems()得到已分页好的结果集 <Kt3PyF
ps.getIndexes()得到分页索引的数组 >M;u*Go`QO
ps.getTotalCount()得到总结果数 \x+3f
ps.getStartIndex()当前分页索引 tju|UhP3
ps.getNextIndex()下一页索引 &`!^Zq vG
ps.getPreviousIndex()上一页索引 aGoE,5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 n$["z
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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 jirbUl
glUo7^ay7
一下代码重构了。 23ze/;6%A
f3tv3>p
我把原本我的做法也提供出来供大家讨论吧: *fc-gAj
c&'JmKV>&
首先,为了实现分页查询,我封装了一个Page类: %fjuG
java代码: z#Nl@NO&
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/*Created on 2005-4-14*/ `-UJ /{
package org.flyware.util.page; 5#2F1NX
jC, FG'P
/** G|u3UhyB
* @author Joa BNucc']
* xWX*tJ4
*/ eon!CE0
publicclass Page { b ,^*mx=
;<wS+4,
/** imply if the page has previous page */ <7sIm^N
privateboolean hasPrePage; K_BPZ5w
^TFs;|..
/** imply if the page has next page */ d- E4~)Qy
privateboolean hasNextPage; 9NpD!A&64<
F%/h*
/** the number of every page */ m7qqY
privateint everyPage; }5 9U}@xC
lmCZ8 j(FF
/** the total page number */ Bl;KOR
privateint totalPage; C+V*
Fh3
t+TYb#Tc
/** the number of current page */ `\Unpp\I
privateint currentPage; s8gU7pT49
0b|zk <
/** the begin index of the records by the current >G"X J<IO
pchBvly+0
query */ s(2GFc
privateint beginIndex; H-5<S@8
%_M2N.n
wts:65~
/** The default constructor */ +cB&Mi5
public Page(){ ^ 4hO8
k#JQxLy#
} j 6)Y
bKbp?-]
/** construct the page by everyPage 2#5,MP~r
* @param everyPage nCxAQ|P?
* */ "$^0%-
public Page(int everyPage){ }
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this.everyPage = everyPage; ?.bnIwQe
} <,1fkq>,
C;rG]t^%
/** The whole constructor */ KFWJ}pNq
public Page(boolean hasPrePage, boolean hasNextPage,
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{Gi h&N
GA3sRFZdQ
int everyPage, int totalPage, =U-r*sGLN
int currentPage, int beginIndex){ )Hw:E71h2
this.hasPrePage = hasPrePage; UWXm?v2j
this.hasNextPage = hasNextPage; 7"v$- W y
this.everyPage = everyPage; -w6
"?
this.totalPage = totalPage; mDMt5(.
this.currentPage = currentPage; h{iEZ#
this.beginIndex = beginIndex; g /+oZU
} WE!vSZ3R
'c`jyn
/** (?&=T.*^
* @return ;h/pnmhP
* Returns the beginIndex. 0tz:Wd*<
*/ K%g;NW
publicint getBeginIndex(){ nKh&-E
return beginIndex; }At{'8*n
} fnu"*5bE
DPDe>3Mi[
/** lPP,`
* @param beginIndex WQePSU
* The beginIndex to set. }iN2KeLAF
*/ /.Jb0h[W1
publicvoid setBeginIndex(int beginIndex){ *,WP,-0
this.beginIndex = beginIndex; dE=Ue#1U@5
} )ZR+lX}
%@J1]E;
/** "5|Lz) =
* @return #Z!b G?="
* Returns the currentPage. M:SO2Czz
*/ vA% ^`5
publicint getCurrentPage(){ \F6LZZ2Lv
return currentPage; c|~6Ie
} e 9$C#D>D
%Z]'!X
/** d5 j_6X
* @param currentPage h#}YKWL
* The currentPage to set. arZ@3]X%a
*/ qoU3"8
publicvoid setCurrentPage(int currentPage){ $&P?l=UG
this.currentPage = currentPage; rP=sG;d
} 773/#c
{bNXedZ\
/** JWO=!^
* @return $.mQ7XDA9
* Returns the everyPage. ]o/|na*
*/ <fO4{k*&
publicint getEveryPage(){ o>D
return everyPage; '` CspY
}
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t!;/Z6\Pb
/** RMYP"
* @param everyPage -e@!
* The everyPage to set. $ChK]v
6C
*/ GUB`|is^
publicvoid setEveryPage(int everyPage){ bha?eN
this.everyPage = everyPage; f^<6`Aeq
} vwGeD|Fb5
hsLzj\)6
/** L;t)c
* @return sKaE-sbJY
* Returns the hasNextPage. b3$k9dmxV+
*/ jFG0`n}I
publicboolean getHasNextPage(){ t,%iL
return hasNextPage; SS.jL)
} Y}R}-+bD/
xyHejE}
/** |Rzy8j*
* @param hasNextPage vP-M,4c
* The hasNextPage to set. 2(YPz|~W
*/ t2{~bzq1X
publicvoid setHasNextPage(boolean hasNextPage){ /uqu32;o
this.hasNextPage = hasNextPage; i, n D5@#
} ]rBM5~
VDEv>u4
/** } /^C|iS7
* @return j8 ,n7!G
* Returns the hasPrePage. >um!Eo
*/ V L( <
publicboolean getHasPrePage(){ V,7%1TZ:
return hasPrePage; +FFG#6e
} 4jmK].
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/** VrP}#3I
* @param hasPrePage 5"Kx9n|
* The hasPrePage to set. 5 MxL*DB=b
*/ @$@mqHI}
publicvoid setHasPrePage(boolean hasPrePage){ %,*$D}H
this.hasPrePage = hasPrePage; 3NK ^AaTK
} q`|CrOzO
$6f\uuTU2"
/** D$k8^Vs
* @return Returns the totalPage. ,\PVC@xJ
* vxlOh.a|/L
*/ wzcai
0y*
publicint getTotalPage(){ USML~]G
z
return totalPage; v[k5.\No
} ph:3|d
Mio>{%/
/** g9h(sLSF
* @param totalPage 25{ uz
* The totalPage to set. XFZ~ #DT&
*/ }2>"<)
publicvoid setTotalPage(int totalPage){ qB6dFl\ (
this.totalPage = totalPage; <|6%9@
} 0&Gl@4oZ"
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} y&T&1o
eH>#6R1-
m 40m<@
6)RbPPeE
/ l>.mK()
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 ]L_w$ev'
Do-^S:.
个PageUtil,负责对Page对象进行构造: {i{xo2<1"
java代码: #~ v4caNx
H.
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h=VqxGC&
/*Created on 2005-4-14*/ dXvt6kF
package org.flyware.util.page; ?^!,vh
yOXO)u1n
import org.apache.commons.logging.Log; Q'NmSX)0
import org.apache.commons.logging.LogFactory; K\!#4>yd
C*Vd -U
/** l)8&Ip
* @author Joa 5OLQw(E
* ReB7vpd
*/ F}?<v8#z0
publicclass PageUtil { x4?10f(9=
,32xcj}j)r
privatestaticfinal Log logger = LogFactory.getLog f|3q^wjs
N_wp{4 0/
(PageUtil.class); C9tb \?#
@|-OJ4[5
/** Qc-(*}
* Use the origin page to create a new page ;6;H*Y0,|E
* @param page 8^ep/ b&|
* @param totalRecords lvSdY(8
* @return *MM#Z?mP
*/ :>
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publicstatic Page createPage(Page page, int nL`9l1
I`B'1"{
totalRecords){ iDb;_?
return createPage(page.getEveryPage(), xp \S2@<
u</8w&!
page.getCurrentPage(), totalRecords); {eZ{]
} t1]6(@mj5
qk{'!Ii
/** %HuyK
* the basic page utils not including exception %IZ)3x3l
l[h'6+o
handler .-I|DVHe
* @param everyPage Q
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* @param currentPage 9(1rh9`=
* @param totalRecords #*$p-I=
* @return page
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*/ kEN#u
publicstatic Page createPage(int everyPage, int %CH6lY=lI
$^% N U
currentPage, int totalRecords){ 0%C^8%(x
everyPage = getEveryPage(everyPage); C0C0GqN,
currentPage = getCurrentPage(currentPage); H'g?llh1J
int beginIndex = getBeginIndex(everyPage, x1[?5n6
S>:,z}i
currentPage); =]>%t]
int totalPage = getTotalPage(everyPage, 4*H"Z(HP
7}
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totalRecords); -$k>F#
boolean hasNextPage = hasNextPage(currentPage, xF8S*,#,*
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totalPage); _9If/RD
boolean hasPrePage = hasPrePage(currentPage); j'rS&BIG
m2bDHQ+
returnnew Page(hasPrePage, hasNextPage, 6qp5Xt+
everyPage, totalPage, I44s(G1jl
currentPage, )/t6" "
F@W*\3)
beginIndex); pWaPC/,g
} /p`&;/V|
5D`26dB2
privatestaticint getEveryPage(int everyPage){ 'x%x'9OP
return everyPage == 0 ? 10 : everyPage; zmFws-+A
} :[7lTp
MiGcA EF;
privatestaticint getCurrentPage(int currentPage){ n'w,n1z7
return currentPage == 0 ? 1 : currentPage; @'jfKW
} 5G*II_j
:hqZPajE
privatestaticint getBeginIndex(int everyPage, int V0i9DK|!
G?)vWM`j
currentPage){ a|qsQ'1,;
return(currentPage - 1) * everyPage; MK$Jj"
} q? z>
<4X?EYaTq
privatestaticint getTotalPage(int everyPage, int =:7$/T'Qg
[?KIN_e#
totalRecords){ 'CV^M(o'9
int totalPage = 0; @z,*K_AKr
KFhG (
if(totalRecords % everyPage == 0) wyQb5n2`;~
totalPage = totalRecords / everyPage; 9C}qVoNu
else &d^=siL
totalPage = totalRecords / everyPage + 1 ; %$X\"
Xa,&ef&q
return totalPage; ^X?D#\
} Ie_I7YJ
y?:dE.5p|
privatestaticboolean hasPrePage(int currentPage){ YMzBAf
return currentPage == 1 ? false : true; Go8F5a@j
} BQrL7y
H!eh
J$[
privatestaticboolean hasNextPage(int currentPage, -Zy)5NB-tZ
kK[duW=6
int totalPage){ S!dHNA:iU
return currentPage == totalPage || totalPage == c ~Kc7}I
d<T%`:s<
0 ? false : true; _/x&<,3
} 2i:zz?
'p`
L,M+sN
WmVVR>0V|
} K8Zt:yP
3N%{B
tbG8MXX
U ":"geU
:YvbU Y
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。 I,P!@
J W"
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 uLW/f=7L
L#j/0IHD
做法如下: i\x~iP&F$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Alu5$6X
$WaZ_kt
的信息,和一个结果集List: /tC9G@Hl
java代码: zO.6WJ
Rc9<^g`
mK\aI
/*Created on 2005-6-13*/ ;'1Apy
package com.adt.bo; /H&aMk}J@y
TA;,>f*
import java.util.List; uBeNXOre
ntH T
import org.flyware.util.page.Page; P;GprJ`l
qx%jAs+~
/** >]/dOH,A
* @author Joa 'lQYJ0
*/ DrS?=C@
publicclass Result { ^, wnp@
m5gI~1(9
private Page page; Oxa5Kfpa
mxL;;-
private List content; TzF0/T!
*.8:'F
/** *8-p7,D
* The default constructor 2Ow<`[7
*/ a<p
%hY3
public Result(){ +Jq`$+%C
super(); !;WbOnLP
} -1m vhR~
~e^)q>Lb7(
/** w2Kq(^?
* The constructor using fields lU$X4JBzS
* ^x3EotQ\
* @param page IwRQL%
* @param content 1v]t!}W:6
*/ W-Of[X{<
public Result(Page page, List content){ ZNy9_a:dX
this.page = page; 6/7F">@j
this.content = content; jtLnj@,
} ^pw7o6}
%EIUAG
/** $rB!Ex{@ac
* @return Returns the content. ?`i|"y#
*/ b%<jUY
publicList getContent(){ P#bm uCOS
return content; ]Zv,
} yA}nPXrd
1ypjyu
/** jkCHi@
* @return Returns the page. *1,=qRjL
*/ )0F^NU
public Page getPage(){ RAOKZ~`
return page; lk o3]A3
} ULu O0\W
o16~l]Z|f
/** c}cG<F
* @param content %&1$~m0
* The content to set. E7LbSZ
*/ hg&u0AQ2
public void setContent(List content){ B$`d&7I;D
this.content = content; @>Ek '~m
} +{^'i P
B3.X}ys#
/** `&,_xUA
* @param page s
kY0 \V
* The page to set. H<z30r/-w
*/ Di])<V
publicvoid setPage(Page page){ pLo;#e8'f
this.page = page; m9I(TOw
} tnJ`D4
} N.vG]%1"
d3(+ztmG!
w'XSb.\)_m
x{j+}'9
++gPv}:$X
2. 编写业务逻辑接口,并实现它(UserManager, ZR2\dH*
-G!6U2*#
UserManagerImpl) `|JI\&z
java代码: I*9Gb$]=
BiE$mM
D/*vj|
/*Created on 2005-7-15*/ (I!1sE!?1
package com.adt.service; 2X^iV09
fGo_NB
import net.sf.hibernate.HibernateException; rNxG0^k(
G\uU- z$)
import org.flyware.util.page.Page; W
n6,U=$3
IY~
{)X
import com.adt.bo.Result; 5@iy3olP
Sn0Xl3yr
/** sB8p(
L
* @author Joa %'kX"}N/
*/ W=F3XYS
publicinterface UserManager { +O,V6XRr
Ho>p ^p
public Result listUser(Page page)throws 03] r*\
x6jm-n
HibernateException; 35}P0+
6\XP|n-0+0
} a0)vvo=bz
&!4(
0u
tRkrV]K
)v};C<
Jfe~ ,cI
java代码: C\J@fpH(t`
#'#4hJ*YC
Dn: Yi8=
/*Created on 2005-7-15*/ VDPxue
package com.adt.service.impl; g8Ok ^
$=7H1 w
import java.util.List; j#CuR7m
s^obJl3
import net.sf.hibernate.HibernateException; I?A~zigO
7/4~>D&-b
import org.flyware.util.page.Page; RlPjki"Mg
import org.flyware.util.page.PageUtil; +<H !3sW
YdPlN];[
import com.adt.bo.Result; vW9^hbdx
import com.adt.dao.UserDAO; FV`3,NFk
import com.adt.exception.ObjectNotFoundException; @f-0X1C."N
import com.adt.service.UserManager; y B1W>s8&
Cx$9#3\
/** BzN/6VEw
* @author Joa h=:*7>}
*/ NuHL5C?To
publicclass UserManagerImpl implements UserManager { B6-AIPb
|WQD=J%~(
private UserDAO userDAO; oJhEHx[f
hcj{%^p
/** {E3;r7
* @param userDAO The userDAO to set. }`#j;H$i
*/ zf}rfn
publicvoid setUserDAO(UserDAO userDAO){ )x y9X0
this.userDAO = userDAO; ?exALv'B
} cPx66Dh&
K,Lr+
/* (non-Javadoc) oC5gME"2
* @see com.adt.service.UserManager#listUser N45s'rF
OX'/?B((
(org.flyware.util.page.Page) qdKh6{
*/ 7'c8]/qh
public Result listUser(Page page)throws Ty)gPh6O
no eb f
HibernateException, ObjectNotFoundException { 0m
qSA
int totalRecords = userDAO.getUserCount(); jY1^+y{
if(totalRecords == 0) rD_Ss.\^g
throw new ObjectNotFoundException 7$;c6_se
JiG8jB7%}
("userNotExist");
c"6Kd$?M
page = PageUtil.createPage(page, totalRecords); N)`tI0/W
List users = userDAO.getUserByPage(page); Ufyxw5u5F
returnnew Result(page, users); ?U7&R%Lh`
} n\~"Wim<b
}S
Y`KoC1
} ag|9$
BF@m)w.v
t201ud2$
hj%}GP{{
aMe%#cLI
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m~b#:4D3
=f/avGX
询,接下来编写UserDAO的代码: wCqE4i
3. UserDAO 和 UserDAOImpl: +3(CGNE
java代码: 6,sRavs
<h)deB+}
G:H(IA7Z
/*Created on 2005-7-15*/ <e@I1iL37y
package com.adt.dao; Ly@U\%.
MZgmv
import java.util.List; ,Gf+U7'K
I$rW[l2
import org.flyware.util.page.Page; 5|{ t+u
j(wY/Hl
import net.sf.hibernate.HibernateException; "Wzij&WkQ
Z3&XTsq
/** F>hVrUD8
* @author Joa vLVSZX
*/ Ktj(&/~}
publicinterface UserDAO extends BaseDAO { 3/]f4D{MMY
-K{\S2
publicList getUserByName(String name)throws #$9U=^Z[
;tZ}i4Ud
HibernateException; C={sE*&dYX
q{N lF$X
publicint getUserCount()throws HibernateException; B{=,VwaP_
6'3Ey'drH
publicList getUserByPage(Page page)throws l%v hV&
>B|ofwm*
HibernateException; ulJ+:zwq$
/
r`Y'rm
} 6"#Tvj~-8
y0W`E/1t
?Vb=4B{~
^ ^U)WB
@DjG?yLK$
java代码: YQlpk@X`2
)[a?J,
zXA= se0U
/*Created on 2005-7-15*/ [bQ8A(u
package com.adt.dao.impl; ^+YGSg7
[xH2n\7
import java.util.List; IWSEssP
av$\@4I
import org.flyware.util.page.Page; 2g`uC}
@=^jpSnZ
import net.sf.hibernate.HibernateException; vCrWA-q#
import net.sf.hibernate.Query; vM$#m1L?
LQuYCfj|
import com.adt.dao.UserDAO; o>!~*b';g,
9 ;! uV>-H
/** **
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* @author Joa W"DxIy
*/ JN9H T0
public class UserDAOImpl extends BaseDAOHibernateImpl w^vK7Z
1$
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implements UserDAO { J0{WqA.P
G/^5P5y%@
/* (non-Javadoc) 2gNBPd )I
* @see com.adt.dao.UserDAO#getUserByName tF) k6*+
^!{ o Azy9
(java.lang.String) t2U]CI%
*/ %E=,H?9&>
publicList getUserByName(String name)throws +b:h5,
wHDFTIDI
HibernateException { ^U|CNB%.
String querySentence = "FROM user in class ^Ypb"Wx8
_@}MGWlAPt
com.adt.po.User WHERE user.name=:name"; +=lcN~U2
Query query = getSession().createQuery
Y=#mx3.
L>K39z~,
(querySentence); E,nYtn|B
query.setParameter("name", name); d%"@#bB
return query.list(); {yl/T:Bh&
} `~s,W.Eu4
_<&K]e@dp
/* (non-Javadoc) 7xa@wa?!L
* @see com.adt.dao.UserDAO#getUserCount() >H]|A<9u(
*/ g#bfY=C
publicint getUserCount()throws HibernateException { 5<>R dLo
int count = 0; 5>^ W}0s
String querySentence = "SELECT count(*) FROM jmwQc&
=FC;d[U
user in class com.adt.po.User"; p{pzOMi6
Query query = getSession().createQuery H;"N|pBy
f%{ ag
(querySentence); WG!;,~f>o
count = ((Integer)query.iterate().next Tef3
Z6
^?l-YnQqm?
()).intValue(); `
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return count; j,V$vK P
} lyc{Z%!3
E6d8z=X(
/* (non-Javadoc) ^#6%*(D
* @see com.adt.dao.UserDAO#getUserByPage 1Tk\n
Yi! >8
(org.flyware.util.page.Page) z ]4g`K+
*/ sGm(Aax*0
publicList getUserByPage(Page page)throws F<'l'AsC-
c$UpR"+
HibernateException { ]9l%
String querySentence = "FROM user in class Jb-QP'$@
@=|
b$E
com.adt.po.User"; ;),O*Z|"v
Query query = getSession().createQuery %A Du[M.
q2o$s9}B
(querySentence); eDMwY$J
query.setFirstResult(page.getBeginIndex()) jn3|9x
.setMaxResults(page.getEveryPage()); f;;
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return query.list(); )@&?i.
} d?+oT0pCH
bT6)(lm
} ff+9(P>*
=2V;B
m">
=QP
ClVpb ew
,h(+\^
?,
至此,一个完整的分页程序完成。前台的只需要调用 Ydd>A\v\;
i)^ZH#Gp
userManager.listUser(page)即可得到一个Page对象和结果集对象 W1,L>Az^Ts
|$-d,] V
的综合体,而传入的参数page对象则可以由前台传入,如果用 -JW6@L@
="nrq&2
webwork,甚至可以直接在配置文件中指定。 M:q;z(
""KN?qh9
下面给出一个webwork调用示例: Xcpm?aTo
java代码: }(7QJk5 j
2\8\D^
g|*eN{g]uE
/*Created on 2005-6-17*/ ;w&yGm
package com.adt.action.user; 7)8}8tY^{
k=/|?%
import java.util.List; B0SmE_u_N
Ej3hdi)
import org.apache.commons.logging.Log; 4oEq,o_
import org.apache.commons.logging.LogFactory; u$ / ]59
import org.flyware.util.page.Page; jtOsb91c}
'-~/!i+=
import com.adt.bo.Result; UA u4x 7
import com.adt.service.UserService; uF|ix.R6
import com.opensymphony.xwork.Action; >WS&w;G
~rfjQPbh9x
/** FH5 bC6
* @author Joa UE;)mZ=l|
*/ sNpBTG@{l
publicclass ListUser implementsAction{ m6ws#%|[
.F$AmVTN
privatestaticfinal Log logger = LogFactory.getLog uM6!RR!~
j24
(ListUser.class); KO;6 1y:
') cgx9
private UserService userService; gBS#Z.
`G5wiyH})
private Page page; ;Z~.54Pf{d
F0(Sv\<::
privateList users; eBRP%<=>D
2%yJo7f$[
/* ;GEu.PdxB
* (non-Javadoc) h*LL(ow5
* N~KRwsDH
* @see com.opensymphony.xwork.Action#execute() t'/;Z:
*/ _o"3gfH&sJ
publicString execute()throwsException{ (dt_ D
Result result = userService.listUser(page); DyTk<L
page = result.getPage(); 1^>g>bn_"
users = result.getContent(); E"yf!*
return SUCCESS; r/<JY5
} ^W05Z!}
)GKgK;=~
/** s;M*5|-
* @return Returns the page. {mitF
*/ -Dm.z16
public Page getPage(){ |6Z MxY
return page; e[dRHl
} <vuX "
8
25[/'7_"
/** odn`%ok
* @return Returns the users. W)~.o/;
*/ %$KO]
publicList getUsers(){ L=FvLii.
return users; *g6o ;c
} Bb"4^EOZ,
v fDb9QP
/** F}DD;K
* @param page E\N=p&g$
* The page to set. (t['
*/ e>Y2q|S85
publicvoid setPage(Page page){ ?0%TE\I8
this.page = page; (:x"p{
} `R?W @,@'
-B(K Q T,J
/** >D#}B1(!
* @param users i?=.;
0[|
* The users to set. rB?cm]G=
*/ kweTK]mT
publicvoid setUsers(List users){ 6x{IY
this.users = users; :J-5Q]#
} l!` 0I] }
*
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/** e!Okc*,
* @param userService W-QPO
* The userService to set. 9v2 ;
*/ -;-"i J0
publicvoid setUserService(UserService userService){ B'/ >Ax&
this.userService = userService; 0.0!5D[
} f~9Y1|6
} $ 3B?
;qK6."b`;
EQ$9IaY.
I!O S&8:u
~=ys~em e
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, !17Z\Ltqyj
tY=TY{ RY
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 c10).zZ
Z?mg1;Q
么只需要: RBD
MZ
java代码: p2(_YN;s
LTct0Gh
db~ :5#*
<?xml version="1.0"?> O+j:L
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork :n9^:srGZH
H\bIO!vb
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~ }22 Dvo
wm71,R1
1.0.dtd"> #wiP{+%b
NvZ?e
<xwork> 4]
1a^@?
ii9/ UtIQ
<package name="user" extends="webwork- ,+9r/}K]/
W9'jzP
interceptors"> uJ[Vv4N%9
xrnH=>.;m
<!-- The default interceptor stack name Y1\vt+`O
0&@pX~h:
--> %T\x~)
<default-interceptor-ref n<*]`do,w
%Ege^4PE
name="myDefaultWebStack"/> J7vpCw2ni
o hlVc%a
<action name="listUser" I|z#Aoc
0 XzO`*
class="com.adt.action.user.ListUser"> -~f.>@Wb
<param Y cpO;md
yFsXI0I[p
name="page.everyPage">10</param> pnJT]?},
<result qTF>!o#\:
3PffQ,c[~
name="success">/user/user_list.jsp</result> UV.9KcN.
</action> 5 ZPUY
x~eEaD5m%J
</package> $uh DBmb
zK?[dO
</xwork> p04+"
"cM5= ;
^mQfXfuL
I_7EfAqg(
It-*CD9
q2vz#\A?
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 fM.|#eLi
A!yLwkc:5
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ze)K-6SKH
{fD#=
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 d?Cl04
KW^aARJ)
J7o?h9
Xs@ ^D,
5V!XD9P'
我写的一个用于分页的类,用了泛型了,hoho cyg>hX{U
k5(yf~!c
java代码: n^#LB*q
&S]v+wF
~7'.{VrU
package com.intokr.util; i{qU RP}.
!3# }ZC2
import java.util.List; puF
Z~WZ
]{^vs'as\
/** D7/Bp4I#o
* 用于分页的类<br> <t{AY^:r
* 可以用于传递查询的结果也可以用于传送查询的参数<br> n4y6Ua9m{
* %;$Y|RbmqE
* @version 0.01 _B FX5ifK
* @author cheng 38i,\@p`9$
*/ K9'*q3z
public class Paginator<E> { 8-YrmP2k
privateint count = 0; // 总记录数 WEAXqDjM
privateint p = 1; // 页编号 +Ob#3PRy
privateint num = 20; // 每页的记录数 *wcoDQ b;
privateList<E> results = null; // 结果 4+,Z'J%\[7
T]-~?;Jh8
/** Fg_s'G,`
* 结果总数 *PU,Rc()6
*/ w[YbL2p
publicint getCount(){ ygt)7f5
return count;
RQNi&zX/
} 4LJ}>e
X{9o8
*V
publicvoid setCount(int count){ j],.`Y
this.count = count; tta0sJ8i
} tdF[2@?+
F:GKnbY
/** ;@~*z4U
* 本结果所在的页码,从1开始 :Xh`.*{EX
* QC,(rB
* @return Returns the pageNo. KdsvZim0>
*/ :9#{p^:o
publicint getP(){ l?_!eA
return p; \RyA}P5S
} -wMW@:M_
b)^ZiRW``
/** -GVG1#5
* if(p<=0) p=1 HW Os@!cL
* [qMdOY%jx
* @param p ?4Juw?
*/ "m;]6B."
publicvoid setP(int p){ %v:h]TA
if(p <= 0) K/m)f#
p = 1; u@u.N2H.%
this.p = p; )uuEOF"w
} g@VndAp
_rd j,F8
/** 9$@ g;?}Ps
* 每页记录数量 q%Jy>IXt
*/ ~9YA!48
publicint getNum(){ [c[MQA0
return num; ~U6YN_W
} 166c\QO
]pTw]SK
/** .ASwX
* if(num<1) num=1 m>dcb
6B+g
*/ ptni'W3
publicvoid setNum(int num){ lA-!~SM v"
if(num < 1) ey\{C`(__y
num = 1; UZXcKl>u
this.num = num; s
Xk?.A_D
} )pn7DIXG
ai
_fN
/** k&iScMgCTH
* 获得总页数 ^|i\d\
*/ 0W%}z}/N
publicint getPageNum(){ `R52{B#&/
return(count - 1) / num + 1; 7 P^{*!
} #_\MD,(
*u;">H*BW
/** :_,]?n
* 获得本页的开始编号,为 (p-1)*num+1 "u8o?8+q~
*/ i)PV{3v$J
publicint getStart(){ lc?mKW9
return(p - 1) * num + 1; 'qF3,Rw
} wW! r}I#
X+E\]X2
/** Dke($Jr{
* @return Returns the results. V0
+k3H
*/ + >gbZ-S
publicList<E> getResults(){ nf.:5I.
return results; @))}\:
} (X_ ,*3Yxk
.>64h H
public void setResults(List<E> results){ &}6ES{Nr8
this.results = results; M:UB>-`bW
} Ld3Bi2d|
$<
K)fbG
public String toString(){ hN:F8r+DG
StringBuilder buff = new StringBuilder 5ZyBP~
Zjic"E1
(); avt>saR
buff.append("{"); ~{,vg4L
buff.append("count:").append(count); <_a70"i
buff.append(",p:").append(p); fqk Dk
buff.append(",nump:").append(num); h?3,B0G
buff.append(",results:").append Lr?4Y
t-7[Mk9@
(results); ]pR fY9w
buff.append("}"); E?gu(\an@
return buff.toString(); L+~YCat|$U
} JQ/t, v$G
[[0bhmG)
} Q^MXiEO+
"^
6lvZP(
&e]]F#