Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 f</'=k
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 dH]0(aJ
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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 FuqMT`
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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 ."`mh&+`
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分页支持类: as#_Fer`U
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java代码: vG E;PwR
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package com.javaeye.common.util; yFt$L'#
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import java.util.List; `D
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publicclass PaginationSupport { 2;8I0BH*'
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publicfinalstaticint PAGESIZE = 30; GJTKqr|1O
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privateint pageSize = PAGESIZE; VtM:~|v
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privateList items; 2=R}u-@6p
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privateint totalCount; {B;<R1
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privateint[] indexes = newint[0]; Cu2eMUGt
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privateint startIndex = 0; jV W .=FK
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public PaginationSupport(List items, int %w9/gD
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totalCount){ k[_)5@2
setPageSize(PAGESIZE); vI84=n
setTotalCount(totalCount); W~" 'a9H/
setItems(items); 7E0L-E=.
setStartIndex(0); ajr);xd
} _ ^ JhncL
!V%h0OE\
public PaginationSupport(List items, int whH_<@!
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totalCount, int startIndex){ tccw0
setPageSize(PAGESIZE); *U<l$gajq
setTotalCount(totalCount); .(
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setItems(items); "pZvV0'
setStartIndex(startIndex); %R|_o<(#MJ
} L>trLD1pt
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public PaginationSupport(List items, int F,hiKq*
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totalCount, int pageSize, int startIndex){ *8I+D>x
setPageSize(pageSize); )Bz2-|\
setTotalCount(totalCount); /5**2Kgv1
setItems(items); J&hzr t
setStartIndex(startIndex); a9f!f %9
} M53{e;.kN
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publicList getItems(){ 'R-Ly^:Qd
return items; UrC>n
} 1\t# *N
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publicvoid setItems(List items){ NA :_yA"
this.items = items; /m"#uC!\
} ~]w|ULNa3|
_ ^2\/@
publicint getPageSize(){ #
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return pageSize; bU3P;a(
} {4C/ZA{|l
crwui 8
publicvoid setPageSize(int pageSize){ B,xohT
this.pageSize = pageSize; \Fh#CI
} bmid;X|
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publicint getTotalCount(){ +VSq [P
return totalCount; jV|j]m&t
} ~10 >mg
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publicvoid setTotalCount(int totalCount){ =/#+,
if(totalCount > 0){ _N @h
this.totalCount = totalCount; c4Leh"ry
int count = totalCount / :cE6-Fv
)qID<j#
pageSize; D4G*Wz8
if(totalCount % pageSize > 0) 8h?):e
count++; ~dtS
indexes = newint[count]; HL`=zB%
for(int i = 0; i < count; i++){ :-[y`/R
indexes = pageSize * |_h$}~;
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i; )0 1,3J>#
}
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}else{ sC}p_'L
this.totalCount = 0; =xs"<Q*w>
} S-
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} uHQf <R$:
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publicint[] getIndexes(){ xHpB/P ~
return indexes; G~+BO'U9'G
} xwJ.cy
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publicvoid setIndexes(int[] indexes){ /19ZyQw9
this.indexes = indexes; ]?<=DHn
} 6Trtulm
!H^e$BA
publicint getStartIndex(){ T?4I\SG
return startIndex; xb (Cd
} ;1MRBk,
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publicvoid setStartIndex(int startIndex){ k|r|*|8
if(totalCount <= 0) Chs#}=gzi
this.startIndex = 0; f\vy5''
elseif(startIndex >= totalCount) 2mt
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this.startIndex = indexes {/2
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|=rb#z&
[indexes.length - 1]; K;'s+ZD
elseif(startIndex < 0) *dpKo&y
this.startIndex = 0; xm*6I
else{ 05ZF>`g*
this.startIndex = indexes {aoG60N
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S@R
[startIndex / pageSize]; Hs#q 7
} U3tA"X.K
} ~gi,ky^!
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publicint getNextIndex(){ tj1M1s|a
int nextIndex = getStartIndex() + Nu[0X
KB5<)[bs
pageSize; 9`FPV`/
if(nextIndex >= totalCount) t,IQ|B&0
return getStartIndex(); Tya[6b!8
else Q13>z%Rge
return nextIndex; ^V?W'~
} 0K:3?Ik
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publicint getPreviousIndex(){ DlF6tcoI
int previousIndex = getStartIndex() - 8`Iz%rw&(J
KM9)
pageSize; $gPR3*0
if(previousIndex < 0) ',l}$]y5
return0; 40m>~I^q}
else -RBH5+SS2
return previousIndex; vwIP8z~<
} +\s&v!
mGC! 7^_D`
} d+L!s7
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抽象业务类 LQ{z}Ay
java代码: qgkC)
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/** ]1dnp]r
* Created on 2005-7-12 @#1T-*
*/ vD91t/_+
package com.javaeye.common.business; Z~Vups#+f
8-geBlCE,
import java.io.Serializable; &<$YR~g5j$
import java.util.List; /s[D[:P_
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import org.hibernate.Criteria; TO]7 %aB
import org.hibernate.HibernateException; zi?G
wh~
import org.hibernate.Session; F- l!i/
import org.hibernate.criterion.DetachedCriteria; =67tQx58
import org.hibernate.criterion.Projections; \Pt_5.bTs[
import $/|2d4O:{
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org.springframework.orm.hibernate3.HibernateCallback; PlC8&$
import 9
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org.springframework.orm.hibernate3.support.HibernateDaoS C| g]Y 7
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upport; jr3FDd]
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import com.javaeye.common.util.PaginationSupport; ?5Q_G1H&
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public abstract class AbstractManager extends YJqbA?i
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HibernateDaoSupport { ){FXonVP
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privateboolean cacheQueries = false; 3x3 =ke!
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privateString queryCacheRegion; MzpDvnI9
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publicvoid setCacheQueries(boolean
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*'\xlsp#
cacheQueries){ Tq,xW
this.cacheQueries = cacheQueries; " ,>,t_J
} g"|/^G_6S
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publicvoid setQueryCacheRegion(String %WO4uOi:@
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queryCacheRegion){ r NT>{
this.queryCacheRegion = !J k|ha~r
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queryCacheRegion; y%@C-:
} ;pVnBi
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publicvoid save(finalObject entity){ .u^4vVz
getHibernateTemplate().save(entity); Ek,$XH
} mY0FewwTy
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publicvoid persist(finalObject entity){ 7Ug^aA
getHibernateTemplate().save(entity); dW} m44X
} tJ9-8ZT*
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publicvoid update(finalObject entity){ bTJ l
getHibernateTemplate().update(entity); 3.@I\p}
} :Lh`Q"a
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publicvoid delete(finalObject entity){ S0jYk (
getHibernateTemplate().delete(entity); 0;n}{26a
} p{W'[A{J .
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publicObject load(finalClass entity, %Z!3[.%F
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finalSerializable id){ A#x_>fV
return getHibernateTemplate().load 6<
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(entity, id); ~X<Ie9m1x
} Cs?[
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publicObject get(finalClass entity, I6.}r2?;A
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}
finalSerializable id){ %}1v- z
return getHibernateTemplate().get ;^9y#muk
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(entity, id); /6Olq6V
} a~Nh6 x
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publicList findAll(finalClass entity){ `2PvE4]%p
return getHibernateTemplate().find("from aZB$%#'vR
o@W:PmKW
" + entity.getName()); T.GB*
} ,!Q^"aOT:
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publicList findByNamedQuery(finalString ]mdO3P
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namedQuery){ [a!*m<
return getHibernateTemplate z!>ml3
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().findByNamedQuery(namedQuery); :WHbwu,L$
}
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publicList findByNamedQuery(finalString query, #{x4s?
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finalObject parameter){ I`4k5KB;
return getHibernateTemplate m'YYkq(5%Z
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().findByNamedQuery(query, parameter); ]m@p? A$
} LR Dj!{k{
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publicList findByNamedQuery(finalString query, qJq!0F
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finalObject[] parameters){ "
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return getHibernateTemplate X3l?
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().findByNamedQuery(query, parameters); 'Z82+uU%
} e%EE|
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publicList find(finalString query){ eiwPp9[08
return getHibernateTemplate().find *Vr;rk
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(query); +~f5dJyk`
} 7?a!x$-U(
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publicList find(finalString query, finalObject >@uF ye$
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parameter){ SnFAv7_
return getHibernateTemplate().find rO7[{<97m
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(query, parameter); _ m<@ou7
} q^^&nz<A
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public PaginationSupport findPageByCriteria E=L1q)
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(final DetachedCriteria detachedCriteria){ 4">C0m;ks
return findPageByCriteria JxLSQ-"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Mv7=ZAm
} W}rL HAaDh
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public PaginationSupport findPageByCriteria tq&CJvJ4
|$&v)
(final DetachedCriteria detachedCriteria, finalint dZ%rmTE(H
{<L|Z=&k`
startIndex){ '/
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return findPageByCriteria cByUP#hW
|7@@~|A
(detachedCriteria, PaginationSupport.PAGESIZE, *D:uFo,xn
*@zya9y9q
startIndex); BfdS3VrZ/
} K\y
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public PaginationSupport findPageByCriteria pu,|_N[xq8
uL9O_a;!
(final DetachedCriteria detachedCriteria, finalint Pe)SugCs
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pageSize, . E?a
finalint startIndex){ Fd1jElt
return(PaginationSupport) L]#b=Y
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getHibernateTemplate().execute(new HibernateCallback(){ p n(y4we
publicObject doInHibernate 4StoEgFS
]=?.LMjnH
(Session session)throws HibernateException { ^Q5advxuq
Criteria criteria = 8 GW0w
!X ={a{<,T
detachedCriteria.getExecutableCriteria(session); S9lT4
int totalCount = NZ:KJ8ea"
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((Integer) criteria.setProjection(Projections.rowCount L#Rj~&U
v#b( 0G
()).uniqueResult()).intValue(); -Gd@baV
criteria.setProjection ^+rI=c 0
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(null); 8;5@5Au
List items = `C>De4nT@
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criteria.setFirstResult(startIndex).setMaxResults yL"UBe}v
+!eh\.u|]
(pageSize).list(); _l{_n2D-
PaginationSupport ps = U_<k*o@:
y?ypRCgO.u
new PaginationSupport(items, totalCount, pageSize, {I]>!V0j!
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startIndex); uow{a*qd6
return ps; Zx
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} jWcfQ
}, true); Z^6qxZJ7
}
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public List findAllByCriteria(final JlhI3`X;/
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DetachedCriteria detachedCriteria){ 6h{>U*N"&d
return(List) getHibernateTemplate gX;)A|9e
x yyEaB
().execute(new HibernateCallback(){ UKzXz0
publicObject doInHibernate R7 ^f|/l
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(Session session)throws HibernateException { o>e -M
Criteria criteria = yt1dYF0Xq
mV#U=zqb!S
detachedCriteria.getExecutableCriteria(session); \VHRI<$+5
return criteria.list(); 7[It
} .F/0:)
}, true); A&L2&ofV&q
} Wh^wKF~%
W
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public int getCountByCriteria(final CM4#Nn=i~
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DetachedCriteria detachedCriteria){ !;M5.Y1j&"
Integer count = (Integer) wH]Y1 m
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getHibernateTemplate().execute(new HibernateCallback(){ ~vB dq Yj
publicObject doInHibernate v{oHC4
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(Session session)throws HibernateException { uL
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Criteria criteria = 8om)A0S
k@^T<Ci
detachedCriteria.getExecutableCriteria(session); Oz-@e%8L
return j71RlS73
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criteria.setProjection(Projections.rowCount g^[BnP)I
3.w &e0Es
()).uniqueResult(); 67]!xy
} |G(I,EPag
}, true); "J>8ZUP
return count.intValue(); OpLUmn
} ,nSapmg
} 8B7~Nq'
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用户在web层构造查询条件detachedCriteria,和可选的 T~)R,OA7m
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 k FCdGl
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PaginationSupport的实例ps。 "GB493=v
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ps.getItems()得到已分页好的结果集 HiSNEp$-4$
ps.getIndexes()得到分页索引的数组 aPm2\Sq$
ps.getTotalCount()得到总结果数 O:jaA3
ps.getStartIndex()当前分页索引 gb}>x O
ps.getNextIndex()下一页索引 C^7M>i
ps.getPreviousIndex()上一页索引 csj4?]gI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 vQmqYyOc2
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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 Ti$_V_
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一下代码重构了。 <`d;>r=4z
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我把原本我的做法也提供出来供大家讨论吧: *Ke\Yb
Uf#9y182*c
首先,为了实现分页查询,我封装了一个Page类: 9YY*)5eyD
java代码: =i>i,>bv
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/*Created on 2005-4-14*/ `u$lSGl
package org.flyware.util.page; Yz? 8n
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/** 3 uJ?;
* @author Joa 91M5F$
* ]}L tf,9
*/ Ao$|`Lgj=z
publicclass Page { (w-@b70E
[ps5
/** imply if the page has previous page */ PG@6*E
privateboolean hasPrePage; 5G l:jRu
V;uFYt;E
/** imply if the page has next page */ k:#u%Z
privateboolean hasNextPage; .~fov8
t4<+]]
/** the number of every page */ ,tak{["
privateint everyPage; y\ax?(z
nx@,oC4
/** the total page number */ LN`Y`G|op
privateint totalPage; USzO):o
oW3|b2D
/** the number of current page */ m-lTXA(
privateint currentPage; <v3pI!)x
=H8Y
/** the begin index of the records by the current R<;;Ph
t^"8
v3'h
query */ J*t_r-z
privateint beginIndex; mZ~f?{
sE! $3|Q
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/** The default constructor */ 3|=L1Pw#
public Page(){ c+501's
F"0=r
} 0}N"L ml
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/** construct the page by everyPage 6Cgc-KNbk
* @param everyPage .q|k459oi
* */ NR98]X
public Page(int everyPage){ :H>0/^Mg0
this.everyPage = everyPage; ftD(ed
} a;=IOQ
bU$M)
/** The whole constructor */ gjn1ha"h%.
public Page(boolean hasPrePage, boolean hasNextPage, ^J)0i_RS
"x
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int everyPage, int totalPage, wicW9^ik
int currentPage, int beginIndex){ dZCnQ IS
this.hasPrePage = hasPrePage; v(=E R%
this.hasNextPage = hasNextPage; LvNulMEK
this.everyPage = everyPage;
75;g|+
this.totalPage = totalPage; 7KN+ @6!x
this.currentPage = currentPage; mX[J15
this.beginIndex = beginIndex; {_UOS8j7
} e*M-y C
,O_iSohS
/** 1u~a*lO}
* @return Rw)=<XV)6
* Returns the beginIndex. ( e4#9
*/ gjk;An
publicint getBeginIndex(){ :ZadPn56
return beginIndex; C4)m4r%
} ;*cCaB0u
mI5!rrRD|
/** >1$Vh=\OI
* @param beginIndex 'cA(-ghY/E
* The beginIndex to set. <[?ZpG
*/ f([d/
publicvoid setBeginIndex(int beginIndex){ vF)eo"_s*
this.beginIndex = beginIndex; f/t`B^}@
} 6N[X:F
3`,
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/** Mk}*ze0%
* @return +asO4'r
* Returns the currentPage. TT={>R[B
*/ hG>kx8h
publicint getCurrentPage(){ 3
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return currentPage; 1}~`g ED
} m]Mm(7v(
" -S@R=bi
/** >65\
* @param currentPage p3V?n[/}
* The currentPage to set. 10^FfwRfM
*/ (U@$gkUx}G
publicvoid setCurrentPage(int currentPage){ 4+MaV<!tU^
this.currentPage = currentPage; M2I*_pI
} 3Scc"9]
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/** vbfQy2q
* @return Z1{>"o:@
* Returns the everyPage. o{3>n"\w3
*/ 0wt4C% .0
publicint getEveryPage(){ ~-#Jcw$+n=
return everyPage; 9-!G Ya'Z
} ZE9.r`
yB|1?L#
/** #3?}MC
* @param everyPage D#gC-,
* The everyPage to set. klnk{R.>|
*/ S|F:[(WaM
publicvoid setEveryPage(int everyPage){ 6zI}?KZf
this.everyPage = everyPage; /7x1Z*Hg
} gux?P2f
Re*_Dt=r
/** u:H:N]
* @return e xkPu-[W
* Returns the hasNextPage. h4Xz"i{z
*/ PJ\k|
publicboolean getHasNextPage(){ *,28@_EwY
return hasNextPage; 6Ad=#MM
} L%+mD$@u
G&08Qb ,N
/** ZEso2|
* @param hasNextPage Hwcm t!y
* The hasNextPage to set. Dt(xj}[tC
*/ 3i~X`@$k>
publicvoid setHasNextPage(boolean hasNextPage){ L3A2A
this.hasNextPage = hasNextPage; 'mZQ}U=<
} )iFXa<5h
O=6[/oc
'
/** %M:$ML6b<
* @return fk!9` p'
* Returns the hasPrePage. sG\K$GP!
*/ sKk+^.K}|
publicboolean getHasPrePage(){ *K BaKS
return hasPrePage; <v=s:^;C0
} ]CPF7Hf
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/** (T%Ue2zlY
* @param hasPrePage k5Su&e4]]
* The hasPrePage to set. s6'=4gM
*/ d{"@<0i?
publicvoid setHasPrePage(boolean hasPrePage){ '_5|9
}
this.hasPrePage = hasPrePage; Jt0U`_
} Wb[k2V
("{"8
/** wB&5q!{!
* @return Returns the totalPage. Q>71uM%e`
* vmh>|N4a7
*/ 3gnO)"$
publicint getTotalPage(){ RC?vU
return totalPage; nLx|$=W
} 6OoOkNWF
6b9J3~d\E
/** )sNPWn8<Uy
* @param totalPage =3!o_
* The totalPage to set. #jd.i
*/ `?b'.Z_J
publicvoid setTotalPage(int totalPage){ wJ7^)tTRF
this.totalPage = totalPage; ~@(C+ 3,
} @C^wV
hRMya#%-
} Cy)N hgz
i<):%[Q)>
"YWZ&_n**
Ay PtbrO
@DF7j|]tV
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 vn!3Z! dm(
kdp^{zW}
个PageUtil,负责对Page对象进行构造: #Ge_3^'
java代码: i,S1|R
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/*Created on 2005-4-14*/ BC\W`K
package org.flyware.util.page; "eqzn KT%u
'GT^araz
import org.apache.commons.logging.Log; !0vLSF=
import org.apache.commons.logging.LogFactory; b`@C #qB
&FuL{YL
/** b%vIaP|]B
* @author Joa Sc/$2gSG
* -e_op'`
*/ Js vdC]+
publicclass PageUtil { `(
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_ Yc"{d3S
privatestaticfinal Log logger = LogFactory.getLog 3zu6#3^
*ra>Kl0
(PageUtil.class); \KzJNCOT
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/** maN2(1hz
* Use the origin page to create a new page szb@2fK
* @param page U| VL+9#hd
* @param totalRecords JgA{1@h
* @return ^;rjs|`K#
*/ CWocb=E
publicstatic Page createPage(Page page, int 3u& ,3:
:~#)Xa0I
totalRecords){ 9 M%Gnz
return createPage(page.getEveryPage(), x^1d9Z
g6;smtu_T
page.getCurrentPage(), totalRecords); O5Z9`_9<
} OM{^F=Ap
K&Bbjb_|
/** Em^~OM3U$q
* the basic page utils not including exception M=lU`Sm
.a7RGT3]m
handler C=]<R<Xy
* @param everyPage >TY;l3ew
* @param currentPage _U-`/r o
* @param totalRecords 9}m?E<6&
* @return page GBT|1c'i
*/ }Z FoCMM
publicstatic Page createPage(int everyPage, int |w54!f6w_
B+mxM/U[c
currentPage, int totalRecords){ @c'iT20
everyPage = getEveryPage(everyPage); q7f`:P9~
currentPage = getCurrentPage(currentPage); ft1#f@b.
int beginIndex = getBeginIndex(everyPage, 3Ovx)qKxd
,[zSz8R
currentPage); ;Q^>F6+_m
int totalPage = getTotalPage(everyPage, BxjSo^n
RL/y7M1j
totalRecords); 2l+L96
boolean hasNextPage = hasNextPage(currentPage, d}':7Np
MP)Prl>
totalPage); kfZ`|w@q
boolean hasPrePage = hasPrePage(currentPage); kLF`6ZXtd
[rWBVfm
returnnew Page(hasPrePage, hasNextPage, ;?tH8jf>
everyPage, totalPage, K) fKL
currentPage, @j_o CDS
h7^&:
beginIndex); U|V,&RlbR
} l`ZL^uT
.P aDR |!
privatestaticint getEveryPage(int everyPage){ f?
@Qt<+k
return everyPage == 0 ? 10 : everyPage; \)r M C]
} jwa6`u
s_XCKhN:
privatestaticint getCurrentPage(int currentPage){ `Wg"m~l$N
return currentPage == 0 ? 1 : currentPage; _,)_(R ,h
} kN
Ll|in@
6QCVi
privatestaticint getBeginIndex(int everyPage, int W"\}##
6j XDLI
currentPage){ 'z
AvQm
return(currentPage - 1) * everyPage; =eUKpYI
} 5X=1a*2']
kSzap+ nB?
privatestaticint getTotalPage(int everyPage, int GEF's#YWK
t;6<k7h
totalRecords){ q+9->D(6
int totalPage = 0; Q=Mv"~2>B
~`FRU/@r
if(totalRecords % everyPage == 0) 8wvHg_U6W
totalPage = totalRecords / everyPage; {)l Zfj}l
else ch]Qz[d
totalPage = totalRecords / everyPage + 1 ; T`":Q1n
''@Tke3IG6
return totalPage; T` h%=u|D
} &)tiO>B^6
G=|?aK{p
privatestaticboolean hasPrePage(int currentPage){ 1F,U^O
return currentPage == 1 ? false : true; 2A;i
} jI7 x<=
BInSS*L
privatestaticboolean hasNextPage(int currentPage, Lv['/!DJ|
dN3^PK
int totalPage){ RU7+$Z0K
return currentPage == totalPage || totalPage == q"<=^vi
t3Gy *B
0 ? false : true; `e<IO_cg
} 9dNkKMc@
SNOc1c<~
rIPfO'T?
} +;lDU}$
7HH@7vpJ^
E> GmFw
<b,WxR`
2PyuM=(Wt
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 s_/@`kd{
t2)uJN`a$X
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 f?tU5EX
Rf8Obk<
做法如下: `WOoC
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ftTD-d
jn|NrvrX
的信息,和一个结果集List: NMK$$0U
java代码: :JG5)H}j+
`aAE4Ry?
Zt!$"N.,
/*Created on 2005-6-13*/ 1[O cZCS
package com.adt.bo; DZ2gnRg
5X)QW5A
import java.util.List; Mb2a;s
z@3gNY&7.8
import org.flyware.util.page.Page; -d'FKOD
M?sax+'
/** :?zq!
* @author Joa z0/+P
*/ Z40k>t
D
publicclass Result { nc:/GxP
g 4=1['wW
private Page page; S?JCi=
7V::P_aUY
private List content; xIm2t~io
'yX\y
6I
/** X,l7>>L{g
* The default constructor xbhHP2F|
*/ 8A&N+sT
public Result(){ j[:70%X
super(); ]rj~3du\
} i=#\`"/
-@>]iBl
/** |e@1@q(a[]
* The constructor using fields Q2ne]MI
* k{;?>=FH!
* @param page mz.,j(Ks-
* @param content GBb8}lx
*/ I\6C0x
public Result(Page page, List content){ %/w-.?bX
this.page = page; w:%NEa,Z
this.content = content; WuY#Kx~2
} U.SC,;N^
m}?jU
/** #Y7iJPO
* @return Returns the content. ];Noe9o
*/ @-S7)h>~
publicList getContent(){ :2c(.-[`
return content; 6/L[`n"G
} _VdJFjY?zc
Z72%Bv
/** n$SL"iezW?
* @return Returns the page. bS8$[7OhX
*/ 7=fNvES2
public Page getPage(){ TDR|*Cs
return page; ? 3fnt"
} Zj]tiN f\"
npkT>dB+
/** k8stXW-w
* @param content lH_pG ~
* The content to set. K\Q4u4DjbJ
*/ %1k"K~eu
public void setContent(List content){ -FZNk}
this.content = content; 1VFCK&
} F%y#)53g
:*
|WE29U
/** &&<l}E
* @param page Szu@{lpP@
* The page to set. I/St=-;
*/ x'}zNEXI
publicvoid setPage(Page page){ &?QKWxN
this.page = page; IxWi>8
} *y<eK0
} 'j'6x'[>]
-V2`[k
.{t5_,P
\\R<HuTY
{f4jE#a>v
2. 编写业务逻辑接口,并实现它(UserManager, 8~,zv_Pl
4>d]0=x
UserManagerImpl) 09vVCM;DY
java代码: ckFPx l.
>?JUGXAi'{
]lGkZyUhI
/*Created on 2005-7-15*/ zwQ#Yvd
package com.adt.service; <Af&Q0J
#s\yO~F-
import net.sf.hibernate.HibernateException; `dX0F=Ag?
6W YVHG
import org.flyware.util.page.Page; Z"Lr5'}
=jm\8sl~~
import com.adt.bo.Result; /<T{g0s
w]xr
~D+
/** gA EB
* @author Joa w$&;s<0
*/ Es}`SIe/
publicinterface UserManager { H'$H@Kn]-
E]vox~xK>
public Result listUser(Page page)throws S3HyB
b
)Dhx6xM[a
HibernateException; ~FAk4z=Ed
)xU+M{p-os
} 6X'0 T}
7fWZ/;p
8H};pu2
e:MbMj6`
% mPv1$FH
java代码: 'e<8j
FU*q9s `
PQ_A^ 95
/*Created on 2005-7-15*/ AwuhFPG
package com.adt.service.impl; w#BT/6W&G
@`B_Q v@
import java.util.List; S/eplz;
-0`n(`2
import net.sf.hibernate.HibernateException; er
BerbEEH
Yevd h<
import org.flyware.util.page.Page; *@@dO_%6
import org.flyware.util.page.PageUtil; "-:g.x*d
j)ln"u0R^B
import com.adt.bo.Result; "tJ[M
import com.adt.dao.UserDAO; vY4}vHH2
import com.adt.exception.ObjectNotFoundException; WyB^b-QmDh
import com.adt.service.UserManager; 73u97oe>1
mcQ
A'
/** pR2U&OA
* @author Joa Jc]k\U
*/ SCn)j:gH;
publicclass UserManagerImpl implements UserManager { NuF?:L[
$mAyM+ ph[
private UserDAO userDAO; h4ntjk|{i7
p/LV^TQ
/** GHi'ek <?^
* @param userDAO The userDAO to set. @+Nf@LJ
*/ yoieWnL}
publicvoid setUserDAO(UserDAO userDAO){ <7Yh<(R e^
this.userDAO = userDAO; keQRS+9
} t<}N>%ZO
k=p[Mlic/
/* (non-Javadoc) t5 ^hZZ
* @see com.adt.service.UserManager#listUser rR{KnM
Mg}/gO%o
(org.flyware.util.page.Page) gE*7[*2?t
*/ }=|{"C
public Result listUser(Page page)throws =%I;Y& K
' qT\I8%
HibernateException, ObjectNotFoundException { b,jo94.G
int totalRecords = userDAO.getUserCount(); ]M "U 'Z
if(totalRecords == 0) ^HuB40
throw new ObjectNotFoundException 4kV$JV.l
(t@!0_5
("userNotExist"); N?,
page = PageUtil.createPage(page, totalRecords); e `JWY9%
List users = userDAO.getUserByPage(page); [ gR,nJH.
returnnew Result(page, users); eMn'z]M&]
} PN J&{4wY
HHgv,bC!
} }=gD,]2x8
spQr1hx<
^)`e}}
2"}Vfy
Ed_Fx'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5~[][VV^
F]N?_ bo
询,接下来编写UserDAO的代码: \?Xoa"^
3. UserDAO 和 UserDAOImpl: ,|#biT-<T
java代码: @0tX,Z9
i3L2N~:V
+4qR5(W
/*Created on 2005-7-15*/ f}.t
package com.adt.dao; H|`D3z.c
^e\$g2).
import java.util.List; 9R-2\D]
d mTZEO
import org.flyware.util.page.Page; <wd;W;B
?} E
M,
import net.sf.hibernate.HibernateException; %SCt_9u
#Lk~{
/** x.Ny@l%]
* @author Joa 8NNs_~+x}
*/ ;V f{3
publicinterface UserDAO extends BaseDAO { qMA";Frt3N
NCo!n$O1~
publicList getUserByName(String name)throws 8B!QqLqK
MlS5/9m@^
HibernateException; @1bl<27
G%!i="/9
publicint getUserCount()throws HibernateException; _2<UcC~
4Xwb`?}-
publicList getUserByPage(Page page)throws nHZhP4W
U ){4W0
HibernateException; 3=Uy t
?Ycl!0m
} *.1#+h/]3
=C|^C3HK
x wwL
(KPD`l8.
oe<@mz/
java代码: X(#8EY}X
HvZSkq^
|-cXb.M[
/*Created on 2005-7-15*/ 1IT(5Mleb
package com.adt.dao.impl; 7j#Ix$Ur
*p\fb7Pu_3
import java.util.List; !4Sd ^"
zITxJx
import org.flyware.util.page.Page; i]@k'2N
NweGK
import net.sf.hibernate.HibernateException; im)r4={
9
import net.sf.hibernate.Query; P{J9#.Zq&s
6V6Mo}QF
s
import com.adt.dao.UserDAO; NMC0y|G
V_ntS&2o
/** =@hCc
* @author Joa PJ<qqA`!
*/ 4?
rEO(SZ
public class UserDAOImpl extends BaseDAOHibernateImpl 1M55!b
| (,{&\
implements UserDAO { =Uo*-EH
d{ B0a1P
/* (non-Javadoc) bcxR7<T,"9
* @see com.adt.dao.UserDAO#getUserByName ,I]]52+?4
tqp i{e
(java.lang.String) S<i.O
*/ 2#/sIu-L
publicList getUserByName(String name)throws X(8LhsP
iO18FfM_
HibernateException { nYvkeT
String querySentence = "FROM user in class Lm1JiPs d
eIf-7S]m
com.adt.po.User WHERE user.name=:name"; U 17=/E
Query query = getSession().createQuery Dk2Zl
~,8#\]xR
(querySentence); q @wX=
query.setParameter("name", name); kK:Wr&X0H
return query.list(); E7w^A
} RjrQDh|((
ip*^eS^
/* (non-Javadoc) 4/ q
BD
* @see com.adt.dao.UserDAO#getUserCount() +Oo-8f*
*/ MhD=\Lpj\
publicint getUserCount()throws HibernateException { z 9WeOs
int count = 0; c]$$ap
String querySentence = "SELECT count(*) FROM "Wb KhE
'L{pS-+6
user in class com.adt.po.User"; Ri::Ek3qu
Query query = getSession().createQuery wM-H5\9n
?zVE7;r4U
(querySentence); D)S_ p&
count = ((Integer)query.iterate().next 1r*@1y<0"
VuK>lY&
()).intValue(); 0r!F]Rm-^
return count; pQ4HX)<P
} ~[BGKqh
PB BJ.!Pb
/* (non-Javadoc) CU*;>h1~u
* @see com.adt.dao.UserDAO#getUserByPage } ,Dk6w$
`@u9 fx.
(org.flyware.util.page.Page) n%02,pC6,
*/ N1x~-2(
publicList getUserByPage(Page page)throws V;Ln|._/t
[`bK {Dq2
HibernateException { E2`9H-6e
String querySentence = "FROM user in class {aK3'-7
K05T`+N,
com.adt.po.User"; q$ j
Query query = getSession().createQuery A\E ))b9+
#~w~k+E4
(querySentence); ol
{N^fiK
query.setFirstResult(page.getBeginIndex()) k!6m'}v
.setMaxResults(page.getEveryPage()); l!\~T"-7;:
return query.list(); H_1&>@ 3
} h^14/L=|
qc3,/JO1
} @ @(O##(7
T5:xia>8O
+-5YmN'
I@#IXH?6
,WW=,P
至此,一个完整的分页程序完成。前台的只需要调用 `ooHABC
rx<P#y]3)
userManager.listUser(page)即可得到一个Page对象和结果集对象 =fB"T+
K;w]sN+I
的综合体,而传入的参数page对象则可以由前台传入,如果用 N+pCC
g$/7km{TP
webwork,甚至可以直接在配置文件中指定。 pRjrMS
wMCgLh\wi
下面给出一个webwork调用示例: 2l:cP2fa
java代码: 6UqDpL7^U
13Q87i5B
RfCu5Kn
/*Created on 2005-6-17*/ p^ OHLT
package com.adt.action.user; N'pYz0_H
+4[9Eb'k=
import java.util.List; ]-;JHB5A_:
- _%~b
import org.apache.commons.logging.Log; 'jye*
import org.apache.commons.logging.LogFactory; "Rtt~["%
import org.flyware.util.page.Page; [.CP,Ly
l$R9c+L=
import com.adt.bo.Result; t"MrrK>T
import com.adt.service.UserService; P1Iy>%3
import com.opensymphony.xwork.Action; 'Ddzlip
hyhm{RC?[
/** ~Ra8(KocD
* @author Joa :wUi&xw
*/ rD !GEU
publicclass ListUser implementsAction{ 2{oQ
oMoco tQ;$
privatestaticfinal Log logger = LogFactory.getLog l2Rnyb<;;
it-2]Nw
(ListUser.class); E!L_"GW
J5xZLv
private UserService userService; ]4K4Nh~
.}(X19R
private Page page; 3 `NSSS
ho^jmp
privateList users; d(KK7SQg
g{K \
/* m )r,
* (non-Javadoc) &!wtH
* K\mFb
* @see com.opensymphony.xwork.Action#execute() y!q`o$nK
*/ b+$wx~PLi
publicString execute()throwsException{ ;r.#|b
Result result = userService.listUser(page); <B @z>V
page = result.getPage(); jTW8mWNk]
users = result.getContent(); r!|h3*YA
return SUCCESS; gplrJaH@
} Ev3,p`zS._
7m:TY>{
/** nXjSf
* @return Returns the page. Eb5BJ-XeS^
*/ l=#b7rBP
public Page getPage(){ /2tPd
return page; J?hs\nA
} -q&,7'V
,F "P/`i'
/** 8u1?\SYnb
* @return Returns the users. nAX/u[
*/ GBT219Z@8
publicList getUsers(){ Wy /5Qw~s
return users; 7=qvu&{
} VM;vLUu!e
ob|^lAU
/** ocpM6b.fK
* @param page ,H$%'s1I(
* The page to set. ,&Vir)S
*/ 3bQq
Nk
publicvoid setPage(Page page){ 5FsfJpw
this.page = page; AWAJ*6Z
} g?cxqC<
)a%E $`
/** t{`krs``
* @param users / neY2D6
* The users to set. 6
tB\X^
*/ ~Qf\DTM&
publicvoid setUsers(List users){ E[BM0.#bZ
this.users = users; Q~KzcB<
} }
na@gn
S5YEz
XG
/** iI &z5Q2
* @param userService ]c]^(C
* The userService to set. 3/]~#y%2
*/ _p^Wc.[~M
publicvoid setUserService(UserService userService){ _!w69>Nj
this.userService = userService; J.O{+{&cd
} KJs`[,;<
} Kb'4W-&u!
+HgyM0LFg
%Z-xh<&
UVW4KUxR
vjA!+_I6
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, @twi<U_
r>sXvzv
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 \c!e_rZ
#CW{y?=
么只需要: #<#-B v
java代码: w?Cho</Xu
V0%a/Hi v
m9\~dD
<?xml version="1.0"?> @CoUFdbz
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork vZ^U]h V
7 ;2>kgf~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $6 4{Ff
m8+
EMBl
1.0.dtd"> }?HWUAL\
A-rj: k!
<xwork> ,-DU)&dF
!\'HKk~V
<package name="user" extends="webwork- *nv^s
5'<mfY'B
interceptors"> lAGntYv
+x~p&,w?
<!-- The default interceptor stack name vN~joQ=d
JgV4-B0
--> 9hJ
a K
<default-interceptor-ref ZkNet>9
4ti,R'
name="myDefaultWebStack"/> U r8JG&,
k?1e+ \
<action name="listUser" y'z9Ya
_94R8?\_V7
class="com.adt.action.user.ListUser"> w$""])o,
<param $4^h>x
\XfLTv
name="page.everyPage">10</param> "{c@}~
<result CioS}K
\6pQ&an
name="success">/user/user_list.jsp</result> Gh<#wa['}
</action> #F6M<V'
[jGE{<Je
</package> @4Q/J$
F;Q'R|HQ
</xwork> WmRu3O
Xo6zeLHO
V?-2FK]
E?VOst&
]O0u.=1k
'aS: Azb
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 V >~\~H2Y
Zv9%}%7p
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。 e2pFX?
~NO7@muw
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 1O1MB&5%
-$,'|\Y
=Ew77
n;QFy5HB8
_:Jma
我写的一个用于分页的类,用了泛型了,hoho [ fs.D /
8~O0P=
java代码: H|'n|\{lt
Y^XZ.R
M<SV H_
package com.intokr.util; e+?;Dc-SJ\
omT^jh
import java.util.List; r?pN-x$M=
!wZIXpeL
/** Pjq()\/[Z
* 用于分页的类<br> L D%SLJ:
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Pj5:=d8z(
* tq L2' (=
* @version 0.01 6H;\Jt
* @author cheng }*vE/W
*/ Q<yvpT(
public class Paginator<E> { t"5ZYa
privateint count = 0; // 总记录数 s%A?B8,
privateint p = 1; // 页编号 aPX'CG4m
privateint num = 20; // 每页的记录数 14(ct
privateList<E> results = null; // 结果 hE'>8 {
`H9!Z$7G
/** OU*skc>
* 结果总数 S8C}C#
*/
E/gfX
publicint getCount(){ n8FIxl&u
return count; j{/5i`5m
} F|P?|
#E#@6ZomT
publicvoid setCount(int count){ (^]3l%Ed
this.count = count; /PG%Y]l0b
} ^KV:.up6
vOl3utu7
/** 2Tv
W 6
* 本结果所在的页码,从1开始 $F]*B
`
* g'EPdE
* @return Returns the pageNo. b27t-p8
*/ Rhw+~gd*F
publicint getP(){ 74hRG~
return p; 6t'.4SR
}
6B}V{2
G}aM~, v
/** X<f4X"y
* if(p<=0) p=1 Ty*+?#`
* v7f[$s$m
* @param p hb>uHUb&
*/ m]}EVa_I`/
publicvoid setP(int p){ pezfB{x?
if(p <= 0) {J/+KK
p = 1; 7'ws: #pC
this.p = p; OUN"'p%%
} yvnvI y
!P6?nS
/** ;Q[E>j?w=
* 每页记录数量 (v$
i
*/ Qz$Wp*
publicint getNum(){ TZdJq
return num; !yz3:Yzu
} KYq<n& s
0;%\L :,O
/** ; NO#/
* if(num<1) num=1 H)rJ>L
*/ :]LW,Eql
publicvoid setNum(int num){ ojVN-*5
if(num < 1) ;)ERxMun
num = 1; sGa "
this.num = num; Vq^b_^
} yP34h*0B
/)4Q%Zp
/** },O7NSG<o
* 获得总页数
8L`wib2
*/ YI]/gWeu
publicint getPageNum(){ xJOp~fKG
return(count - 1) / num + 1; V h5\'Sn
} gA 19f
x$pz(Q&v
/** _6]tbni?v
* 获得本页的开始编号,为 (p-1)*num+1 Mv:\T%]
*/ `*i:z'
publicint getStart(){ r'@7aT&_
return(p - 1) * num + 1; bKh}Y`
} ft!D2M
x@|10GC#:
/** )[=C@U
* @return Returns the results. {l\Ep=O vx
*/ -:Q"aeC5
publicList<E> getResults(){ N_(-\\mq
return results; VuH}@
} tn |H~iF{
khQfLA
public void setResults(List<E> results){ `'pfBVBz
this.results = results; eGWwPSIp
} "M,Hm!j
n+s=u$%qn
public String toString(){ f^Q)lIv
StringBuilder buff = new StringBuilder Q{~;4+ZD
gU?M/i2
(); B.);Ju
buff.append("{"); g$z6*bL
buff.append("count:").append(count); +Edq4QYwR
buff.append(",p:").append(p); G%CS1#
buff.append(",nump:").append(num); +5%ncSJx
buff.append(",results:").append <B+
WM
;U? 323Z
(results); rgEN~e'
buff.append("}"); >B.KI}dE
return buff.toString(); uY3?(f#
} sjHcq5#U!
Q0L1!}w
} R,-DP/ (im
<4I`|D3@
raM{!T: