Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {gkzo3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?-Zl(uX
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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 s ]XZQr%
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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 9Gc4mwu
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分页支持类: [`4
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java代码: d2a*xDkv
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package com.javaeye.common.util; h4#y'E!,Z
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import java.util.List; -Lhq.Q*a
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publicclass PaginationSupport { QJ,[K_
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publicfinalstaticint PAGESIZE = 30; o"!C8s_6
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privateint pageSize = PAGESIZE; ,6EhtNDu
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privateList items; *671MJ9
, UsY0YC
privateint totalCount; i$5<>\g
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privateint[] indexes = newint[0]; { MV,>T_
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privateint startIndex = 0; 1.tAl6]
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public PaginationSupport(List items, int ,r8#-~A6,A
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totalCount){ YO'aX
setPageSize(PAGESIZE); bEKh U\@=J
setTotalCount(totalCount); %b[>eIJU#
setItems(items); 2{Y~jYt{h
setStartIndex(0); z?^oy.
} re~T,PPM
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public PaginationSupport(List items, int p9>1a j2a
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totalCount, int startIndex){ B[,AR"#b
setPageSize(PAGESIZE); uCr :+"C
setTotalCount(totalCount); ?o6X_UxW!
setItems(items); M>_vsI^I'
setStartIndex(startIndex); k-Yli21-/|
} QR2S67-
~].?8C.>*
public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ w^"IR
setPageSize(pageSize); v YJ9G"E
setTotalCount(totalCount); ?g9:xgkF
^
setItems(items); d9&
setStartIndex(startIndex); `/O AgV"`
} jF}-dfe
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publicList getItems(){ Vw|P;LLl`
return items; M#_|WL~
} F8S>Ld
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publicvoid setItems(List items){ PjD9D.
this.items = items; ;1HzY\d%<
} q6,z 1A"
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publicint getPageSize(){ n$F~
return pageSize; Fw S>V2R
} uGv|!UQw
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publicvoid setPageSize(int pageSize){ L>h|1ZK
this.pageSize = pageSize; yQ)&u+r
} A;<wv>T
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publicint getTotalCount(){ [j}JCmWY
return totalCount; _i_P@I<M|~
} " Lh&s<[
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publicvoid setTotalCount(int totalCount){
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if(totalCount > 0){ 6w=`0r3hy
this.totalCount = totalCount;
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int count = totalCount / XEnu0gr
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pageSize; }v's>Ae~p
if(totalCount % pageSize > 0) 2Rt6)hgY
count++; Khb Ku0Z
indexes = newint[count]; AhD C5ue=
for(int i = 0; i < count; i++){ jU $G<G
indexes = pageSize * sH.=Faos
_jc_(;KPF
i; V)5K/ U{
} rlaeqG
}else{ 9O- 2
this.totalCount = 0; lm6hFvEZ
} &JXb) W
} ME$J42
~o>Gm>5!HH
publicint[] getIndexes(){ Zwm/ c]6`
return indexes; drMMf[
} H %c6I
lxm/*^
publicvoid setIndexes(int[] indexes){ M.K^W `
this.indexes = indexes; XC5/$3'M&
} @ 5^nrB
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publicint getStartIndex(){ (Vr%4Z8
return startIndex; %@Z;;5 L
} 4EHrd;|
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publicvoid setStartIndex(int startIndex){ hJ$9Hb
if(totalCount <= 0) <sw@P":F
this.startIndex = 0; "(3u)o9
elseif(startIndex >= totalCount) 0'Si
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this.startIndex = indexes \XPGA uEo
<^\rv42'(2
[indexes.length - 1]; j)2I+[aoB
elseif(startIndex < 0) Z4EmRa30 p
this.startIndex = 0; &iInru3
else{ w`;HwK$ ,
this.startIndex = indexes fz\Q>u'T
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[startIndex / pageSize]; }b1FB<e]
} ":_II[FPY
} IH;sVT$M
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publicint getNextIndex(){ `0N7G c
int nextIndex = getStartIndex() + g"Y_!)X
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pageSize; ]'`E
if(nextIndex >= totalCount) PR
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return getStartIndex(); &s='$a;4
else UWF
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return nextIndex; QYMfxpiC
} yo=L1;H
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publicint getPreviousIndex(){ ZRG
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int previousIndex = getStartIndex() - P&uSh?[ ^
)-26(aNGT
pageSize; 7IkPi?&{
if(previousIndex < 0) H.m]Dm,z
return0; !JDr58
else ;U|(rM;
return previousIndex; {2h*NFp
} b!P,+!<
\ dFE.4
} 0k5-S~_\
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抽象业务类 3l~+VBR_
java代码: BYB4-,
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/** 4LKpEl.=
* Created on 2005-7-12 :Ln)j%&
*/ T@tsM|pI
package com.javaeye.common.business; (T_-`N|
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import java.io.Serializable; 3uocAmY
import java.util.List; +Yc^w5 !(
lN#j%0MaUo
import org.hibernate.Criteria; 1EXT^2!D
import org.hibernate.HibernateException; F(yR\)!C
import org.hibernate.Session; 68XJ`/d
import org.hibernate.criterion.DetachedCriteria;
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import org.hibernate.criterion.Projections; Cgx:6TRS
import k1<^Ept
nwU],{(Hgr
org.springframework.orm.hibernate3.HibernateCallback; |Dn Zk3M,
import ZC N}iQu4
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org.springframework.orm.hibernate3.support.HibernateDaoS 1ysfpX{=
5c` ;~
upport; AH#mL
-N*[f9EJB
import com.javaeye.common.util.PaginationSupport; $6a9<&LP_
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public abstract class AbstractManager extends Y"H`+UV
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HibernateDaoSupport { @."K"i'Bl
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privateboolean cacheQueries = false; xoKK{&J
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privateString queryCacheRegion; -G.N
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publicvoid setCacheQueries(boolean rGP;0KtQ
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cacheQueries){ s<zN`&t
this.cacheQueries = cacheQueries; V: D;?$Jl
} "V' r}>
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publicvoid setQueryCacheRegion(String LDr?'M!D
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queryCacheRegion){ 9\4x<*
this.queryCacheRegion = VcrMlcnO
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queryCacheRegion; `;j1H<L
} +MX~1RU+
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publicvoid save(finalObject entity){ ^Kz?SO
getHibernateTemplate().save(entity); I?'*vAW<
} 8\rca:cF
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publicvoid persist(finalObject entity){ ~6f/jCluR%
getHibernateTemplate().save(entity); G'\[dwD,u
} J@2jx4
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publicvoid update(finalObject entity){ 1m~|e.g_'`
getHibernateTemplate().update(entity); [c3!xHt5O
} 3Y)&[aj
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publicvoid delete(finalObject entity){ mD9Iao%4~
getHibernateTemplate().delete(entity); y||
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} 9i\RdJv.
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publicObject load(finalClass entity, 3+Lwtb}XPF
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finalSerializable id){ ;\7`G!q
return getHibernateTemplate().load rr
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(entity, id); /(^-=pAX
} 4;6"I2;zfG
h"1}j'2>@
publicObject get(finalClass entity, Fqeqn[,
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finalSerializable id){ 9
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return getHibernateTemplate().get j\>&]0-Iq
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(entity, id); GJB+]b-
} u&l;\w
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publicList findAll(finalClass entity){ 6>WkisxG
return getHibernateTemplate().find("from jWUrw
b$'%)\('g
" + entity.getName()); 5;XC!Gz
} 8WytvwB}
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publicList findByNamedQuery(finalString eQ'E`S_d
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namedQuery){ e8`d<U
return getHibernateTemplate 4BMu0["6|s
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().findByNamedQuery(namedQuery); "o--MBq4
} (f&V 7n
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publicList findByNamedQuery(finalString query, .V!5Ui<
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finalObject parameter){ aG7Lm2{c"
return getHibernateTemplate OAkqPG&w
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().findByNamedQuery(query, parameter); ":eyf3M
} I;XM4a
- k0a((?
publicList findByNamedQuery(finalString query, D\G 8p;
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finalObject[] parameters){ r3Ol?p
return getHibernateTemplate aUMiRm-
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().findByNamedQuery(query, parameters); tXzuP_0
} <IZr..|O
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publicList find(finalString query){
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return getHibernateTemplate().find $D`Kz*/.
OkRb3}
(query);
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} EZWWvL
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publicList find(finalString query, finalObject Ls2,+yo]>
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parameter){ ~[!Tpq5
return getHibernateTemplate().find MTwzL<@$
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(query, parameter); _Q #[IH9
} HHx5VI
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public PaginationSupport findPageByCriteria eF;Jj>\R+i
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(final DetachedCriteria detachedCriteria){ 6<z#*`U1
return findPageByCriteria jXx~5
/\ fR6|tJ
(detachedCriteria, PaginationSupport.PAGESIZE, 0); C,ldi"|
} qi@Nz=t#HJ
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public PaginationSupport findPageByCriteria Oh}52=
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(final DetachedCriteria detachedCriteria, finalint `$"{-
9F3aT'3#!
startIndex){ #F/W_G7 v
return findPageByCriteria Fp B3SJ6 B
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(detachedCriteria, PaginationSupport.PAGESIZE, Cno[:iom
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startIndex); aAcQmq TT
} yodhDSO5i
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public PaginationSupport findPageByCriteria *r4FOA%P
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, rXSw@pqZ&
finalint startIndex){ r{~b4~kAf5
return(PaginationSupport) uGC%3!f!
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getHibernateTemplate().execute(new HibernateCallback(){ A
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publicObject doInHibernate `MT.<5H
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(Session session)throws HibernateException { ,H|K3nh
Criteria criteria = pw))9~XU
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detachedCriteria.getExecutableCriteria(session); k-4z2qB
int totalCount = Yi-,Pb?
{DVMs|5;^
((Integer) criteria.setProjection(Projections.rowCount 7iy 2V;}
Us[F@
()).uniqueResult()).intValue(); 6Po{tKU
criteria.setProjection asW
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{#t7lV'4
(null); E?&YcVA
List items = R<3 -!p1v
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criteria.setFirstResult(startIndex).setMaxResults 7#HSe#0J
uv$utu><
*
(pageSize).list(); %f\j)qw
PaginationSupport ps = x[&)\[t
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new PaginationSupport(items, totalCount, pageSize, P e}
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startIndex); A{3nz DLI
return ps; ]:#W$9,WL
} h1Y^+A_
}, true); pgUjje>#
} *>GRU8_}
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public List findAllByCriteria(final PE_JO(e;Xm
8XCT[X
DetachedCriteria detachedCriteria){ ZP:+ '\&J
return(List) getHibernateTemplate uxX 3wY;M
^]/V-!j
().execute(new HibernateCallback(){ '8^cl:X
publicObject doInHibernate #T>pu/EQX_
kB?Uw#
(Session session)throws HibernateException { ZKS]BbMZa
Criteria criteria = 3#uc+$[
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detachedCriteria.getExecutableCriteria(session); e ?Jgk$"
return criteria.list(); d_[zt)
} sVlQ5M oo(
}, true); #|V)>")
} H ~<.2b
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public int getCountByCriteria(final 1yS:`
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DetachedCriteria detachedCriteria){ *\0h^^|@
Integer count = (Integer) /*6[Itm_h
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getHibernateTemplate().execute(new HibernateCallback(){ |*~SR.[`
publicObject doInHibernate (76tYt~I=
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(Session session)throws HibernateException { 5o^\jTEl^
Criteria criteria = M"Y,kA|+
^= kr`5
detachedCriteria.getExecutableCriteria(session); '~{kR=+
return @E> rqI;`
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criteria.setProjection(Projections.rowCount YvUV9qps~
DRVvC~M-,
()).uniqueResult(); n482?Wp
} (AG((eV
}, true); &jrc]
return count.intValue(); 7a4Z~r27/
} 8qUNh#
} b.
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用户在web层构造查询条件detachedCriteria,和可选的 [t?:CgI)E
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .;dI&0Z
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PaginationSupport的实例ps。 OP``+z>
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ps.getItems()得到已分页好的结果集 |QyZ:`0u
ps.getIndexes()得到分页索引的数组 h.xtkD)Y~
ps.getTotalCount()得到总结果数 rj29$d?Y9
ps.getStartIndex()当前分页索引 rLp0)Go
ps.getNextIndex()下一页索引 <.
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ps.getPreviousIndex()上一页索引 ~T=a]V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 +[V.yY/t|>
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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 Wm!cjGK
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一下代码重构了。 IRsyy\[kp8
cOdgBi
我把原本我的做法也提供出来供大家讨论吧: /vLW{ %
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首先,为了实现分页查询,我封装了一个Page类: .aC/ g?U
java代码: 7Y
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/*Created on 2005-4-14*/ Xz'o<S
package org.flyware.util.page; -{p~sRc&
5[`f(;
/**
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* @author Joa ^= qL[S6/M
* M?qvI
*/ yh+.Yn=+
publicclass Page { =]L ALw
eB<R"Yvi
/** imply if the page has previous page */ EuKkIr/(
privateboolean hasPrePage; =BO>Bi&&
C:vVFU|4
/** imply if the page has next page */ |cl*wFm|3
privateboolean hasNextPage; /b."d\
3oPyh $*
/** the number of every page */ `dgZ `#
privateint everyPage; 1+Q@RiW
S0lt_~
/** the total page number */ XrGP]k6.^
privateint totalPage; % 3<7HY]~
15kkf~Z<t
/** the number of current page */ ,a":/ /[
privateint currentPage; @h%Nn)QBq
dTQW /kAHQ
/** the begin index of the records by the current To,*H OP
whQJWi=ck
query */ PebyH"M(
privateint beginIndex; ~Vf
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/** The default constructor */ 1-sG`%
public Page(){ O-n JuZJgX
!{b4+!@p
} G^le91$
G54`{V4&s
/** construct the page by everyPage |+Tq[5&R
* @param everyPage ?:i,%]zxC
* */ 6P02=
public Page(int everyPage){ PeJIa
%iE
this.everyPage = everyPage; !WTL:dk
} ?DKY;:dZF
:c9 H2
/** The whole constructor */ X?'pcYSL
public Page(boolean hasPrePage, boolean hasNextPage, ]3L/8]:
MAL;XcRR
`ix&j8E22w
int everyPage, int totalPage, n]jw!;
int currentPage, int beginIndex){ a" L9jrVrw
this.hasPrePage = hasPrePage; sY&Z/Y
this.hasNextPage = hasNextPage; G
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this.everyPage = everyPage; IJD E{)
this.totalPage = totalPage; >LW}N!IBy
this.currentPage = currentPage; ~P'i
/*:
this.beginIndex = beginIndex; nNh5f]]
} @el
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/** 6K^O.VoV^J
* @return wQ81wfr1:
* Returns the beginIndex. No*[@D]g
*/ H`rd bE
publicint getBeginIndex(){ aAgQ^LY
return beginIndex; m{r#o?
} '%y;{,g*
`pqTiV
/** gzN51B =D
* @param beginIndex !i\ gCLg2_
* The beginIndex to set. +tJ 7ZR%
*/ WF<3
7"A@
publicvoid setBeginIndex(int beginIndex){ 22 feYm|
this.beginIndex = beginIndex; \q^:$iY~
} eU8p;ajW!L
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/** #Sg"/Cc
* @return R1(3c*0f
* Returns the currentPage. E@4/<;eKK
*/ .sD=k3d
publicint getCurrentPage(){ ~nApRC)0
return currentPage; S1U[{R?,
} w[AL'1s]
]88qjKL
/** $dG:29w
* @param currentPage U_WO<uhC
* The currentPage to set. w8a49 Fv
*/ \J;_%-Z
publicvoid setCurrentPage(int currentPage){ I:("f+
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this.currentPage = currentPage; z, n[}Q#u
} hw=~%f;
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/** *q+X?3
* @return "<LWz&e^^
* Returns the everyPage. Zpz3?VM(
*/ ],Yy)<e.
publicint getEveryPage(){ /@I`V?Q!a
return everyPage; 6"R'z#{OF
} >T-4!ZvS\j
=nqHVRA
/** dg_w$#
* @param everyPage 'c# }^@G
* The everyPage to set. U>DCra;
*/ uF<?y0t
publicvoid setEveryPage(int everyPage){ gFsqCx<q
this.everyPage = everyPage; Eihn%Esa
} KD?b|y@
bP> Kx-%q
/** tS-gaT`T
* @return 73Hm:"Eqd
* Returns the hasNextPage. Fu5c_"!
*/ ,e$6%R
publicboolean getHasNextPage(){ kpxGC,I^*.
return hasNextPage; '.k'*=cq0
} ^b.#4i(v
RGrQ>'RL
/** <>728;/C
* @param hasNextPage 6&il>
* The hasNextPage to set. @_1cY#!
*/ m.<u!MI
publicvoid setHasNextPage(boolean hasNextPage){ Qxk & J
this.hasNextPage = hasNextPage; o4wSt6gBcJ
} jcb&h@T8kv
|gIE$rt-~W
/** fH$#vRcq
* @return mhy='AQJ
* Returns the hasPrePage. 9zY6hh**
*/ 3R0ioi 7
publicboolean getHasPrePage(){ $sS~hy*
return hasPrePage; pdvnpzj
} >F s/Wet
T5z]=Pd"^
/** Q<gUu^rq
* @param hasPrePage `.J17mQe"
* The hasPrePage to set. MpBdke$
*/ FRQ0t!b<M1
publicvoid setHasPrePage(boolean hasPrePage){ K6sXw[VC[
this.hasPrePage = hasPrePage; w)`XM
} @\o"zU
*l=(?Pe<
/** Eku9u
* @return Returns the totalPage. PjH'5Y
* Wky9wr:g
*/ -$DfnAh
publicint getTotalPage(){ v; R2,`[W
return totalPage; xiDgQTDz
} Fk^N7EJ:$
*UJ4\
/** om2N*W.gk
* @param totalPage dvU{U@:sz
* The totalPage to set. {_/ o' 6
*/ /;Hr{f jl{
publicvoid setTotalPage(int totalPage){ _TGs .t
this.totalPage = totalPage; *3rs+0
} igW* {)h3
-%@ah:iJ
} 5doi4b>]!
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w jD<"p;P
+`_0tM1
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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 O9p s?{g
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个PageUtil,负责对Page对象进行构造: J=k=cFUX
java代码: "RN]
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8-Y*b89
%,~?;JAj
/*Created on 2005-4-14*/ 28`s+sH
package org.flyware.util.page; 3%5a&b
&JcatI
import org.apache.commons.logging.Log; -5 D<zP/
import org.apache.commons.logging.LogFactory; %1.F;-GdsW
YO$D-
/** f&mi nBU
* @author Joa BdF/(Pg
* yCvtglAJ4
*/
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publicclass PageUtil { XUA@f*
7HBf^N.
privatestaticfinal Log logger = LogFactory.getLog zh*D2/r
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(PageUtil.class); ?-vWNv
[`t ;or
/** C5 Q!_x(
* Use the origin page to create a new page )iQ^HZ
* @param page Dws)
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* @param totalRecords O~6%Iz`
* @return D2kmBZ3
*/ uVCH<6Cp
publicstatic Page createPage(Page page, int Z|%h-~
_X~O6e-!
totalRecords){ (8)9S6
return createPage(page.getEveryPage(), BEvY&3%l
?'z/S5&j
page.getCurrentPage(), totalRecords); CV.|~K0O
} &h5Y_no GX
fy4zBI@
/** Q_|}~4_+
* the basic page utils not including exception %DYh<U4N
"(7y%TFt:
handler A*?PH`bY
* @param everyPage d\l{tmte
* @param currentPage rB$~,q&.V
* @param totalRecords rZJJ\ , |
* @return page >kK@tJn
*/ ZBK0`7#&EH
publicstatic Page createPage(int everyPage, int H3<tsK=:
8 O9^g4?
currentPage, int totalRecords){ CTRUr"
everyPage = getEveryPage(everyPage); r)pt(*KHo
currentPage = getCurrentPage(currentPage); Sb /?<$>
int beginIndex = getBeginIndex(everyPage, Sv{n?BYq
XGR2L
DR
currentPage); s@ @Km1w
int totalPage = getTotalPage(everyPage, A-T-4I
_&hM6N
totalRecords); mi7?t/D1Z
boolean hasNextPage = hasNextPage(currentPage, 2c 0;P
#ol
QQ .?A(U7
totalPage); \ +%~7Bi]z
boolean hasPrePage = hasPrePage(currentPage); ~p?ArZb
XNWtX-[^@
returnnew Page(hasPrePage, hasNextPage, e^>>"tr
everyPage, totalPage, ['=O>YY
currentPage, '7sf)0\:<p
# dUKG8-HJ
beginIndex); {MUiK5:
} e"%TU
N7_eLhPt*8
privatestaticint getEveryPage(int everyPage){ ]EX6Y
return everyPage == 0 ? 10 : everyPage; DOKe.k
} kg]6q T;Y
J 7R(X
privatestaticint getCurrentPage(int currentPage){ |6JKB'
return currentPage == 0 ? 1 : currentPage; I.jqC2G
} =#Sw.N
w5HIR/kP
privatestaticint getBeginIndex(int everyPage, int m7'<k1#"Y
UJI2L-;Ul
currentPage){ 6MT
(k:
return(currentPage - 1) * everyPage; SWV*w[X<X
} U.Mfu9}#:
)OV0YfO
privatestaticint getTotalPage(int everyPage, int [! $NTt_
Y7}Tuy dC
totalRecords){ 7z4k5d<^_
int totalPage = 0; o{sv<$
\dtiv& x
if(totalRecords % everyPage == 0) -<s Gu9
totalPage = totalRecords / everyPage; ^el+ej/=
else ][$I~nRf
totalPage = totalRecords / everyPage + 1 ; 5
3%>)gk:
z!"vez
return totalPage; 4|`>}Nu
} +twoUn{#
2e1KF=N+
privatestaticboolean hasPrePage(int currentPage){ 6WY/[TC-
return currentPage == 1 ? false : true; @=Q!a (g
} XGx[Ny_A2
Ik0g(-d
privatestaticboolean hasNextPage(int currentPage, (?|M'gZ
$9,&BW_*
int totalPage){ ,/{e%J
return currentPage == totalPage || totalPage == v745FIy<
z$%twBg}#
0 ? false : true; eIkKsgr>
} Food<(!.>
Y~I<L ocv
`pfIgryns
} *U[yeE].
@Dh2@2`>
FOXSs8"c]!
uAn}qrqE9
5daq}hsQs
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。 @L3XBV2
T$%|=gq
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 p\w<~pN[
t%lat./yT
做法如下: rm[C{Pn
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >$4#G)s
$d?W1D<A
的信息,和一个结果集List: HT;^u"a~
java代码: ]3_b3@k
,;`f* #
Tlw'05\{J
/*Created on 2005-6-13*/ @sXv5kZ:
package com.adt.bo; Al-`}g+^
:>1nkm&Eg
import java.util.List; ==dKC;
MET9rT
import org.flyware.util.page.Page; n3a.)tcC
_%nz-I
/** ^e.-Ji
* @author Joa pE5v~~9Ikv
*/ %2}fW\%'
publicclass Result { X;I9\Cp]!
.{V"Gn9!
private Page page; #CC5+
jc5[r;#
private List content; "?8)}"/f
|?!i},Ki;
/** &W2*'$j"_
* The default constructor 928_e)V
*/ ue_wuZi
public Result(){ I^y<W%Et
super(); UY',n,
} _?tpO61g>
w'
7sh5
/** c7e,lgG-
* The constructor using fields {X!OK3e
* /WuYg
OI
* @param page C~ 1]
* @param content 1R2IlUlzFr
*/ &9yZfp
public Result(Page page, List content){ \2\{c1df
this.page = page; >+2&7u
this.content = content; jf9+H!?^N
} y{ur'**l
en<~_|J
/** N,(!
* @return Returns the content. "_{NdV|a
*/ /I%z7f91O
publicList getContent(){ n4K!Wv&u
return content; \Vyys[MMY8
} #<*Vc6pC
AC,RS7
/** [9; @1I<x
* @return Returns the page. UqP{Cyy{
*/ ]\(8d[4
public Page getPage(){ s4|\cY`b-
return page; 7~7L5PRW
} QN:v4,$d
vF72#BNs
/** kK? SG3
* @param content PYkhY;*
* The content to set. I|@+O#
*/ /DQYlNa
public void setContent(List content){ gEh/m.L7
this.content = content; da$FY7
} y9:4n1fg
Tgdy;?
/** -k'<6op
* @param page G@8)3 @
* The page to set. H[=\_X1o(
*/ (80m'.X
publicvoid setPage(Page page){ .biq)Le
this.page = page; Kj4/fB
} ]VI^ hhf
} ATs_d_Sz
K`4lL5oH
{r^_ g(.q
:Jd7q.
4V+bE$Wu
2. 编写业务逻辑接口,并实现它(UserManager, 1h,iWHC
/5@YZ?|#2
UserManagerImpl) &.)=>2
java代码: |2(q9j
;ArwEzo(
dOhSqx56
/*Created on 2005-7-15*/ +,Eam6g{
package com.adt.service; ZEqW*piI
]M?i:A$B
import net.sf.hibernate.HibernateException; yM_/_V|G
A}9Z%U
import org.flyware.util.page.Page;
WTSh#L
yaUtDC.|
import com.adt.bo.Result; \v2!5z8|
E>~R P^?Uz
/** n$iX6Cd
* @author Joa =?i?-6M
*/ &W<7!U:2m
publicinterface UserManager { [M|^e;tWK
=*\s`ox`
public Result listUser(Page page)throws ;blL\|ch;
,Z`}!%?
HibernateException; H/,KY/>i
z*.AuEK?
} aKI"<%PNn
y=3 dGOFB
P>/:dt'GJ}
o@meogkL
}d[(kC_
java代码: ^FVdA1~/
i)i>Ulj*i
_4S^'FDo
/*Created on 2005-7-15*/ "hIYf7r##
package com.adt.service.impl; $WA wMS,
IiYL2JS;t|
import java.util.List; xR+vu>f
N`8K1{>BH
import net.sf.hibernate.HibernateException; 9CDei~
%>|FJ
import org.flyware.util.page.Page; 6= ?0&Bx&
import org.flyware.util.page.PageUtil; ;_}pIO
2#wnJdr6E
import com.adt.bo.Result; bWe2z~dP
import com.adt.dao.UserDAO; w\buQ6pR)
import com.adt.exception.ObjectNotFoundException; (.J/Ql0Y
import com.adt.service.UserManager; MO`Y&<g~A
\/
bd
/** U8_{MY-9}
* @author Joa hRkCB
*/ |$Yk)z3
publicclass UserManagerImpl implements UserManager { sI>w#1.m/&
t@%w:*&
private UserDAO userDAO; ^~4]"J};M
N?\X2J1
/** (Y1*Bs[l
* @param userDAO The userDAO to set. <A3%182
*/ 'Ru(`"
1|
publicvoid setUserDAO(UserDAO userDAO){ =EJ&=t
this.userDAO = userDAO; ?t/qaUXN
} iOfm:DTPr
l}nV WuD
/* (non-Javadoc) (i&+= +"wn
* @see com.adt.service.UserManager#listUser "x,lL
8ro`lX*F@2
(org.flyware.util.page.Page) JE.$]){
*/ ~
#jQFyOh
public Result listUser(Page page)throws H%_^Gy8f
q"d9C)Md
HibernateException, ObjectNotFoundException { 8hGyh#
int totalRecords = userDAO.getUserCount(); y_X6{}Ke
if(totalRecords == 0) oz!)x\m*H
throw new ObjectNotFoundException `z!AjAT-G
z'L0YqXG/
("userNotExist"); ~Ntk-p
page = PageUtil.createPage(page, totalRecords); T3w%y`K
List users = userDAO.getUserByPage(page); _){|/Zd
returnnew Result(page, users); g/GI'8EMj
} y0%@^^-Ru
} z'Jsy[s
} De$~ *2
(5T>`7g8
9*"
-]3 K#M)s
(HNc9QVC'W
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Mc,79Ix"
,np=m17
询,接下来编写UserDAO的代码: ?2@^O=I
3. UserDAO 和 UserDAOImpl: jWdviS9&g
java代码: ] \yIHdcDi
Ib(C`4%
;c 7I "?@z
/*Created on 2005-7-15*/ prJd'
package com.adt.dao; ne#dEUD
'|C%X7
import java.util.List; !Dd'*ee-;
. ,|C>^
import org.flyware.util.page.Page; e@3SF
!LKxZ"
import net.sf.hibernate.HibernateException; {;$oC4
jz!I +
/** M5bE5C
* @author Joa d9{lj(2P
*/ r-qe7K@p
publicinterface UserDAO extends BaseDAO { _zj^k$ j
%"
iX3
publicList getUserByName(String name)throws }dc0ZRKgx
A
mZXUb
HibernateException; !W}sOK7#
&h:4TaD
publicint getUserCount()throws HibernateException; Bii'^^I;?
!vz'zy)7
publicList getUserByPage(Page page)throws hFV,FBsAO
r S@/@jKZE
HibernateException; & SXw=;B
yP58H{hQM8
} 7?dWAUF
O-,
"/Z
* +
T(i
,_V V;P
BJ
UG<k
java代码: :zL)O
,{*g
Q%7
2ZK]}&yC
/*Created on 2005-7-15*/ Ip8ml0oG
package com.adt.dao.impl; ]J Yz(m[
+C%6jGGh
import java.util.List; &bTCTDZh
n Bm ]?
import org.flyware.util.page.Page; dGZie.Zx
o2fih%p?1
import net.sf.hibernate.HibernateException; }aWy#Oe
import net.sf.hibernate.Query; tLzLO#/n
eRUdPPq_d
import com.adt.dao.UserDAO; _H$Lu4b)N
hjL;B'IL
/** hBU)gP75
* @author Joa w =GMQ8
*/ ) .KA0-
public class UserDAOImpl extends BaseDAOHibernateImpl 5]O{tSj
gWj-@o\
implements UserDAO { O:?3B!wF
;yNc7Vl
/* (non-Javadoc) $PJ==N
* @see com.adt.dao.UserDAO#getUserByName .IW`?9O$E
J[}H^FR
(java.lang.String) 9evr!=":
*/ ` GF w?G
publicList getUserByName(String name)throws P<pv@l9)
'rhgM/I
HibernateException { Lu#q o^
String querySentence = "FROM user in class yTZev|ej@
|))NjM'ZBl
com.adt.po.User WHERE user.name=:name"; Lc!2'Do;
Query query = getSession().createQuery }nrjA0WN
+&.zwniSS
(querySentence); 15ailA&(Qm
query.setParameter("name", name); fRS;6Jc
return query.list(); Cm[}DB
} e:O,$R#g
e)sR$]i:v
/* (non-Javadoc) b
3x|Dq .
* @see com.adt.dao.UserDAO#getUserCount() Xs2}n^#i
*/ oSCaP,P
publicint getUserCount()throws HibernateException { Sa g)}6+
int count = 0; W
)FxN,
String querySentence = "SELECT count(*) FROM ~qinCIj
9c^ ,v_W@
user in class com.adt.po.User"; ~0MpB~ {xd
Query query = getSession().createQuery =E9\fRGU
j_JY[sex
(querySentence); Tpl]\L1v-
count = ((Integer)query.iterate().next
0pE>O7
D:T]$<=9
()).intValue(); i{^T;uAE
return count; wOAR NrPx2
} QFP9"FM5F
H )ej]DXy
/* (non-Javadoc) ACyK#5E
* @see com.adt.dao.UserDAO#getUserByPage Mj@2=c
7
$y;-[E[
(org.flyware.util.page.Page) &g|[/~dIr
*/ -[=~!Qr:
publicList getUserByPage(Page page)throws $a_y-lY
3;>ls~4
HibernateException { d]DV\*v
String querySentence = "FROM user in class |5 V0_79
y[m,t}gi
com.adt.po.User"; ` aVp#
Query query = getSession().createQuery d{YvdN9d
A.>mk598
(querySentence); 'rB%a<
query.setFirstResult(page.getBeginIndex()) ]oP1c-GEk
.setMaxResults(page.getEveryPage()); !|[rh,e]
return query.list(); ;1(^H:7T
} ofB:7
RHUZ:r
} >~o-6g
t6"%u3W8M
6?a`'&
l*l*5hA
Vuz.b.,i`
至此,一个完整的分页程序完成。前台的只需要调用 a{`hAI${
UF+Qx/4h0
userManager.listUser(page)即可得到一个Page对象和结果集对象 2>o[
*2h%dT:,%
的综合体,而传入的参数page对象则可以由前台传入,如果用 G4(R/<J,BQ
?Bf>G]zx
webwork,甚至可以直接在配置文件中指定。 &J3QO%
3RaduN]
下面给出一个webwork调用示例: AR[m+E
java代码: u`'"=Y_E
E0ED[d,
^8
VW$}
/*Created on 2005-6-17*/ WE\TUENac(
package com.adt.action.user; I[?\Or
nXT`7
import java.util.List; yXU.PSG*
gkr9+
import org.apache.commons.logging.Log; p#$/{;yy
import org.apache.commons.logging.LogFactory; 4Fg2/O_3
import org.flyware.util.page.Page; x*1wsA
z$Jm1l
import com.adt.bo.Result; P)vD?)Q
import com.adt.service.UserService; FCt<h/
import com.opensymphony.xwork.Action; DP{nvsF
` @ QZK0Ox
/** e?W
,D0h
* @author Joa M`Q$-#E:
*/ 9tHK_),9
publicclass ListUser implementsAction{ |0[Buh[_:c
~$y"Ldrp
privatestaticfinal Log logger = LogFactory.getLog AQ)gj$
m3
6=f)3!=
(ListUser.class); cO
J`^^P
Wk[a|>
private UserService userService; `vBBJ@f4)
AlQhKL}|s
private Page page; mG1~rI
C~2!@<y
privateList users; p]kEH\
sh
TsFhrtnx&X
/* -lo?16w
* (non-Javadoc) 9"P+K.%
* M+%Xq0`T
* @see com.opensymphony.xwork.Action#execute() 6 - 3?&+
*/ 'C5id7O&
publicString execute()throwsException{ h7#\]2U$[5
Result result = userService.listUser(page); <q7o"NI6FZ
page = result.getPage(); T]\1gs41
users = result.getContent(); V#Wy`
ce
return SUCCESS; GlJ[rD
} ^("b~-cJ
&@lfr623
/** e* [wF}))
* @return Returns the page. w-Ph-L/
*/ ~:Rbd9IB
public Page getPage(){ 0z/*JVka
return page; TnQ>v{Rx
} P&Keslk
RiTL(Yx
/** PSJj$bt;<+
* @return Returns the users. &@6xu{o
*/ Ll
KO(Q{"
publicList getUsers(){ 4
{M
return users; 5{HF'1XgZ*
} H q6%$!q
UV2W~g
/** }R;}d(C`
* @param page dqB,i9--
* The page to set. AGFA;X
*/ oL]uY5eZoe
publicvoid setPage(Page page){ BvP\c_
this.page = page; ]faj j\
} Ts.2\-+3
q|ce7HnK
/** atZe`0
* @param users 2.Z#\6Vj
* The users to set. ^;F/^_
*/ {<{VJGY7T
publicvoid setUsers(List users){ 8-<F4^i_i
this.users = users; S})f`X9_}
} '#c#.O
?;RY/[IX6
/** u.yR oZ8/!
* @param userService U$5x#{AFp
* The userService to set. J?V$V
>d
*/ byI"
?
publicvoid setUserService(UserService userService){ %1
)c{7
this.userService = userService; dy+A$)gY<
} {]6-,/3UR
} -Mr_Ao`E
B=O zP+
!\#Wq{p>W*
DCp8rvUI
P6_Hz!vE
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, e[iv"|+
y^H5iB[SPL
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 N'y<<tTA
+2{ f>KZ
么只需要: rfonM~3?'
java代码: - ;gQy[U
`i.fm1I]
W_@ b. 1
<?xml version="1.0"?> :Fhk$?/r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork h2'6W)
bf/6AY7
1.0//EN" "http://www.opensymphony.com/xwork/xwork- J299mgB
V%4P.y
1.0.dtd"> v9 \n=Z
V<5. 4{[G
<xwork> C
r R/
$*eYiz3Ue
<package name="user" extends="webwork- [CEV&B
"3VX9{'%@
interceptors"> -n7@r
D zD5n
<!-- The default interceptor stack name .iV=ybMT
{-I+
--> At@0G\^
<default-interceptor-ref |"K%Tvxe
+7%?p"gEY\
name="myDefaultWebStack"/> o<A-ETx<
_1?u AQ3,
<action name="listUser" 29grb P
HKbV@NW
class="com.adt.action.user.ListUser"> R'Ue>k
<param KGOhoiR9:C
}-:B`:K&
name="page.everyPage">10</param> [NE!
<result >h%>s4W
U~=?I)Ni
name="success">/user/user_list.jsp</result> k(G6` dY
</action> @Nb/n
|-6`S1.
</package> <SJ6<'
7[=G;2<
</xwork> 8qkQ*uJP
eTjPztdJbx
#8XmOJ"W3k
1$DcE>
oC"
[rn
{$EX :ID
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 s2L]H
5 v.&|[\k
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 A'CD,R+gR
3]1 !g6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 '?$@hqQn
|?jgjn&RQ
`<>#;%
}o]}R#|
A)~oD_ooQ
我写的一个用于分页的类,用了泛型了,hoho ;F1y!h67<
xppnBnu$7
java代码: +8ib928E
$G <r2lPy
KPy)%i
package com.intokr.util; (@NILK
,>#\aO1n
import java.util.List; rbOJ;CK
j8M t"B
/** `~\SQ EY$
* 用于分页的类<br> +h-% {
* 可以用于传递查询的结果也可以用于传送查询的参数<br> d>#',C#;
* fwUvFK1G
* @version 0.01 .]exY
i
* @author cheng kj|Oj+&
*/ i5(qJ/u
public class Paginator<E> { n]vCvmt
privateint count = 0; // 总记录数 [3=Y 9P:
privateint p = 1; // 页编号 ,l!>+@
privateint num = 20; // 每页的记录数 An>ai N]
privateList<E> results = null; // 结果 b`%u}^B {
<- sr&
/** Zl%)#=kO
* 结果总数 V%[t'uh
*/ fqbWD)L]
publicint getCount(){ 0X99D2c
return count; jSBz),.XU}
} {
#B/4
512p\x@
publicvoid setCount(int count){ uB\UIz)e
this.count = count; w8S
pt
} ,y"vf^BE.
+EA ")T<l
/** F%zMhX'AG
* 本结果所在的页码,从1开始 y)LX?d
* _GY2|x2c
* @return Returns the pageNo. 3R$R?^G
*/ Hwd^C2v
publicint getP(){ VO1
return p; ai/]E6r
} i+QVs_jW
'N6oXE
/** 7gLk~*
* if(p<=0) p=1 Ax|'uvVAPT
* I`xC0ZUKj
* @param p [x?9<#T
*/ ":e6s co
publicvoid setP(int p){ '/D2d
if(p <= 0) BbFLT@W4
p = 1; QDJ#zMxFD
this.p = p; ~9@527m<',
} U*N{H$ACuR
T/u61}'U{
/** s`Z.H5V>\
* 每页记录数量 `"'u
mIz
*/ ekfa"X_
publicint getNum(){ ^Rl?)_)1HE
return num; _&G_SNa
} +5-|6
6f0o'
/** A'}!'1
* if(num<1) num=1 V@RdvQy
*/ _nzTd\L88
publicvoid setNum(int num){ X:f5t` ;
if(num < 1) H!FaI(YZl
num = 1; V*?QZ;hCP
this.num = num; 1fJ~Wp @1
} a{^2c!
3J8>r|u;1'
/** ADxje%!1O
* 获得总页数 08AD~^^
*/ 2xi;13?
publicint getPageNum(){ 82)=#ye_P
return(count - 1) / num + 1; X ?ZLmP7|
} US's`Ehx
* >2FcoN;
/** {]|<|vc;GI
* 获得本页的开始编号,为 (p-1)*num+1 V]]!0ugvk(
*/ tpzh
publicint getStart(){ d/+s-g p
return(p - 1) * num + 1; 2_bEo
} 67H?xsk@n
LO%e1y
/** FwKY;^`!d
* @return Returns the results. 9A{D<h}yk
*/ n}9<7e~/
publicList<E> getResults(){ 9I5AYa?
return results; ,[N(XstI
} Q|VBH5}1O
:
maBec)
public void setResults(List<E> results){ n<)A5UB5-
this.results = results; 39[ylR|\
} 9%R"(X)
nT~XctwF
public String toString(){ MdEds|D
StringBuilder buff = new StringBuilder K}n.k[Do
~[aV\r?
(); 2!9W:I7
buff.append("{"); s LD Ea
buff.append("count:").append(count); u46Z}~xf b
buff.append(",p:").append(p); >X[:(m'
buff.append(",nump:").append(num); 7[L%j;)bw
buff.append(",results:").append %WP[V{,F
C\Ob!sv%H
(results); )_Hv9!U]e
buff.append("}");
v9TIEmZ
return buff.toString(); HdY#cVxy
} Y[VXx8"p
gs.+|4dv
} 18kWnF]n=
<%|u1cn~!v
Mc8_D,7