Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 csP4Oq\g[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4Mt3<W5
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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 )OI}IWDl
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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 ,GSiSn
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分页支持类: VVJ0?G
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java代码: 5rsz2;#p
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package com.javaeye.common.util; ?C|'GkT
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import java.util.List; g[} L
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publicclass PaginationSupport { #}7T$Va
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publicfinalstaticint PAGESIZE = 30; d{fd5jv;
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privateint pageSize = PAGESIZE; RY;V@\pRY+
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privateList items;
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privateint totalCount;
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privateint[] indexes = newint[0]; e{x>u(
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privateint startIndex = 0; =xk>yw!O)
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public PaginationSupport(List items, int G&oD;NY@/
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totalCount){ b7.7@Ly
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setPageSize(PAGESIZE); o/-RGLzAo
setTotalCount(totalCount); B^2r4
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setItems(items); 5{=+S]
setStartIndex(0); -Q? i16pM
} [n"eD4 )K|
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public PaginationSupport(List items, int @X/ 1`Mp
@qNY"c%HV
totalCount, int startIndex){ @`[e1KQ
setPageSize(PAGESIZE); k$$SbStD
setTotalCount(totalCount); L?ZSfm2<
setItems(items); )@!fLAT
setStartIndex(startIndex); dA<%4_WZty
} }83
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public PaginationSupport(List items, int 2J=`"6c
=%` s-[5b
totalCount, int pageSize, int startIndex){ xP\s^]e
setPageSize(pageSize); #$UwJ B]_D
setTotalCount(totalCount); 0moA mfc
setItems(items); ,7V?Kj
setStartIndex(startIndex); Do4hg $:40
} kn:hxdZ
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publicList getItems(){ Ou[`)|>
return items; &$s:h5HoX
}
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publicvoid setItems(List items){ pCt2-aam
this.items = items; '{WEyhaS
} >lIzeEW#
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publicint getPageSize(){ "|JbdI]%P
return pageSize; .]E(P
} .u mqyU~
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publicvoid setPageSize(int pageSize){ |&K;*g|a
this.pageSize = pageSize; y A5h^I
} lITd{E,+r
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publicint getTotalCount(){ h[dJNawL
return totalCount; du$lS':`
} 7 7bwYKIn
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publicvoid setTotalCount(int totalCount){ T.cTL.}
if(totalCount > 0){ FWu:5fBZY
this.totalCount = totalCount; /)[-5n{
int count = totalCount / Z"c-Ly{vEj
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pageSize; +E.
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if(totalCount % pageSize > 0) bIm4s
count++; 4L>8RiiQE;
indexes = newint[count]; kk5&lak2V
for(int i = 0; i < count; i++){ }"+"nf5h
indexes = pageSize * e/hCYoS1n
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i; "d<ucj
} 6"iNh)
}else{ EY]H*WJJ
this.totalCount = 0; *
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} l^I?@{W
} ~Bl,_?CBr
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publicint[] getIndexes(){ mh4 VQ9
return indexes; dF `7]
} ,q%X`F
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publicvoid setIndexes(int[] indexes){ A< .5=E,/
this.indexes = indexes; G-i2#S
} g5U,
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publicint getStartIndex(){ Foq3==*p
return startIndex; `XF[A8@h
} AyQ5jkIE^{
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publicvoid setStartIndex(int startIndex){ 9+ Mj$
if(totalCount <= 0) MP}-7UA#K
this.startIndex = 0; P,ZQ*Ju
elseif(startIndex >= totalCount) $cn8]*Z=
this.startIndex = indexes d7BpmM
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[indexes.length - 1]; F3V:B.C
elseif(startIndex < 0) F4~OsgZ'N
this.startIndex = 0; cAN8'S(s1
else{ n',7=~
this.startIndex = indexes .WSn Y71
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[startIndex / pageSize]; @F 8NN\
} Q1Qw45$
} (,sz.
vE`;1UA}
publicint getNextIndex(){ cFie;k
int nextIndex = getStartIndex() + a1_ N~4r`
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pageSize; ,X|FyO(p
if(nextIndex >= totalCount) @[joM*U
return getStartIndex(); w}6~t\9D
else 47Vt8oyh%
return nextIndex; '`k
} !^Ay!
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publicint getPreviousIndex(){ >"UXY)
int previousIndex = getStartIndex() - -N/n|{+F
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pageSize; +)h# !/
if(previousIndex < 0) zEQQ4)mA
return0; xBc$qjV
else N6kMl
return previousIndex; O<wH+k[
} xK0;saG#
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} o1 27? ^
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抽象业务类 L$a{%]I
java代码: u`B/ 9-K)y
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/** Dd0yQgCu
* Created on 2005-7-12 ^{J^oZ'%~
*/ tag)IWAiE
package com.javaeye.common.business; 44n41.Q]
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import java.io.Serializable; A"DGn
import java.util.List; Y#): 1C1
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import org.hibernate.Criteria; 9(X~
import org.hibernate.HibernateException; !<h9XccN
import org.hibernate.Session; f dJg7r*
import org.hibernate.criterion.DetachedCriteria; LDw.2E
import org.hibernate.criterion.Projections; zZ9Ei-Q
import Yrf?|,
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org.springframework.orm.hibernate3.HibernateCallback; \{rhHb\|h
import r#j3O}(n
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org.springframework.orm.hibernate3.support.HibernateDaoS W|;`R{<I%
ZJ)>gV
upport; 1IgTJ" \
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import com.javaeye.common.util.PaginationSupport; 8>|4iT
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public abstract class AbstractManager extends /QlzWson
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HibernateDaoSupport { ZQR)k:k7
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privateboolean cacheQueries = false; y]i}j,e0L
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privateString queryCacheRegion; W#d'SL#5
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publicvoid setCacheQueries(boolean zB7^L^Y
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cacheQueries){ ~yngH0S$[b
this.cacheQueries = cacheQueries; bA6^RIf?
} x`p908S^
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publicvoid setQueryCacheRegion(String !}`[s2ji
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queryCacheRegion){ ]9<H[5>$R
this.queryCacheRegion = !#5y%Bf
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queryCacheRegion; w4^$@GtN
} ^eV K.
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publicvoid save(finalObject entity){ 4*n1Xu7^x
getHibernateTemplate().save(entity); L`:V]p
} >)[W7h
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publicvoid persist(finalObject entity){ H93ug1,
getHibernateTemplate().save(entity); u3 +]3!BQ
} ok-q9dM
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publicvoid update(finalObject entity){ 2c,w
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getHibernateTemplate().update(entity); Q^Vch(`&P
} `LwZ(M-hI
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publicvoid delete(finalObject entity){ CJ3/8*;w
getHibernateTemplate().delete(entity); 8;UkZN"hy5
} RXWdqaENx
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publicObject load(finalClass entity, a*,V\l|6
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finalSerializable id){ ncsk(`lo
return getHibernateTemplate().load 0|\JbM
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(entity, id); o9{1_7K
} s}^W2
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publicObject get(finalClass entity, #5{lOeN
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finalSerializable id){ =xH>,-8}
return getHibernateTemplate().get ZTGsZ}{5
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(entity, id); A,#z_2~
} dDYor-g>
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publicList findAll(finalClass entity){ -|czhO)R
return getHibernateTemplate().find("from 3=Xvl 58k
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" + entity.getName()); ;$r!eFY;
} Nw1 .x
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publicList findByNamedQuery(finalString ccW{88II7w
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namedQuery){ p2GN93,u@P
return getHibernateTemplate q~\[P4m
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().findByNamedQuery(namedQuery); qm=9!jqC;
} )qWO}]F
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publicList findByNamedQuery(finalString query, CS xB)-
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finalObject parameter){ 1ww~!R
return getHibernateTemplate MLmk=&d
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().findByNamedQuery(query, parameter); X=k|SayE8
} X*r?@uK5
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publicList findByNamedQuery(finalString query, i8/"|+Z
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finalObject[] parameters){ 0w$1Yx~C
return getHibernateTemplate ',Oc+jLR
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().findByNamedQuery(query, parameters); %8"Aq
} i?F~]8
y= 1(o3(
publicList find(finalString query){ ,ce$y4%(
return getHibernateTemplate().find (jh0cy}|]
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(query); ns[h_g!j;
} _lOyT$DN
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publicList find(finalString query, finalObject !;U}ax;AF
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parameter){ y(r(q
return getHibernateTemplate().find `b5pa `\4
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(query, parameter); G7HvA46
} pmDFmES
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public PaginationSupport findPageByCriteria }Do$oyAV$G
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(final DetachedCriteria detachedCriteria){ -fx$)d~
return findPageByCriteria qEPC]es|T
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \//{\d
} KlRIJOS
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public PaginationSupport findPageByCriteria f:A1j\A?
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(final DetachedCriteria detachedCriteria, finalint _ Av_jw`m
<(o) * Zmo
startIndex){ z`y^o*qc]
return findPageByCriteria ){i
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(detachedCriteria, PaginationSupport.PAGESIZE, &m@DK>
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startIndex); oSs~*mf
} !o`h*G-x
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@,
public PaginationSupport findPageByCriteria U#n1N7P|$F
;[j)g,7{
(final DetachedCriteria detachedCriteria, finalint ]A:G>K
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pageSize, Dn.%+im-u
finalint startIndex){ ca$K)=cDW
return(PaginationSupport) A!`Q[%$
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getHibernateTemplate().execute(new HibernateCallback(){ p w`YMk
publicObject doInHibernate 3gba~}c)
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(Session session)throws HibernateException { $)M5@KT
Criteria criteria = 7brC@+ZD
b,RQ" {
detachedCriteria.getExecutableCriteria(session); glRHn?p
int totalCount = kCU(Hi`Q
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((Integer) criteria.setProjection(Projections.rowCount E$E#c8I:
fUS1`
()).uniqueResult()).intValue(); iXuSFman
criteria.setProjection H_ 7E K
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(null); kR;Hb3hb
List items = V3>JZH`
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criteria.setFirstResult(startIndex).setMaxResults ,CQg6-[
#?RT$L>n
(pageSize).list(); ,9~2#[|lq
PaginationSupport ps = t\\`#gc9~i
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new PaginationSupport(items, totalCount, pageSize, : ]~G9]R`
~~3 BV,
startIndex); xEqr3(
return ps; :PDyc(s{
} h2m@Q={
}, true); xIa8Ac
} IpI|G!Y,
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public List findAllByCriteria(final Ya-kMUW
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate ORo,.#<
tx||<8
().execute(new HibernateCallback(){ 5X,|Pn
publicObject doInHibernate rE$=~s
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(Session session)throws HibernateException { ?=0BU}
Criteria criteria = h_K!ch}
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detachedCriteria.getExecutableCriteria(session); c^EU&q{4
return criteria.list(); [$%O-_x
} ,ftKRq
}, true); L~>~a1p!
} C{U"Nsu+1
jk fc=O6^
public int getCountByCriteria(final RD0=\!w *5
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DetachedCriteria detachedCriteria){ e4(E!;Z!QF
Integer count = (Integer) i5jsM\1j
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getHibernateTemplate().execute(new HibernateCallback(){ 0hM!#BU5K
publicObject doInHibernate o0:RsODl
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(Session session)throws HibernateException { {#4F}@Q
Criteria criteria = BDz7$k]
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detachedCriteria.getExecutableCriteria(session); BXB ZX@jVk
return &'<e9
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criteria.setProjection(Projections.rowCount S!+}\*
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()).uniqueResult(); 8t
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} bE>"DPq
}, true); nb}rfd.
return count.intValue(); -|_MC^)
} {>n\B~*,"C
} b]k9c1x
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用户在web层构造查询条件detachedCriteria,和可选的 0*yD
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6w)a.^yx7
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PaginationSupport的实例ps。 \x;`8H
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ps.getItems()得到已分页好的结果集 25{-GaB
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 ^c| _%/
ps.getStartIndex()当前分页索引 &r)[6a$fW
ps.getNextIndex()下一页索引 1V:I}~\
ps.getPreviousIndex()上一页索引 G[$g-NU+
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 " `FcW
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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 x7ZaI{
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一下代码重构了。 Ra/Pk G-7
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我把原本我的做法也提供出来供大家讨论吧: Lv
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首先,为了实现分页查询,我封装了一个Page类: %8{nuq+c
java代码: 7!U^?0?/
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/*Created on 2005-4-14*/ O+OUcMa,
package org.flyware.util.page; J"~!jrzBh(
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/** 6|n3e,&A2
* @author Joa o2~P
vef
* z"P/Geb:O
*/ `3yK<-
publicclass Page { nM|Cv
oju,2kpH7#
/** imply if the page has previous page */ #f<3[BLx
privateboolean hasPrePage; S`8Iu[Ma
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/** imply if the page has next page */ );;UA6CD
privateboolean hasNextPage; T:Nc^QP|tm
T/]f5/
/** the number of every page */ .tcdqL-'
privateint everyPage; T.}Y&,n$$5
@ Fkhida
/** the total page number */ s@IgaF {
privateint totalPage; Z\3~7Ek2m
&EmG\vfE
/** the number of current page */ {B-*w%}HU
privateint currentPage; IGNU_w4j
,&.$r/x|?
/** the begin index of the records by the current >#VNA^+t
C),i#v
query */ 2Gh&h(
privateint beginIndex; lg
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/** The default constructor */ \@[,UZ
public Page(){
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} R$X~d8o>%
O,JS*jXl
/** construct the page by everyPage _&%FGcAS
* @param everyPage T@A Qe[U'v
* */ F?^L^N^
public Page(int everyPage){ $*|M+ofQ
this.everyPage = everyPage; cj9C6Y!
} 2Qt!JXC
~7anj.
/** The whole constructor */ "hi03k
public Page(boolean hasPrePage, boolean hasNextPage, %=!] 1
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T'{9!By,P
int everyPage, int totalPage, k/(]1QnW
int currentPage, int beginIndex){ NfUt\ p*
this.hasPrePage = hasPrePage; F1A40h7R$Y
this.hasNextPage = hasNextPage; IC?(F]$%>
this.everyPage = everyPage; $<yhEvv
this.totalPage = totalPage; .5uqc.i"f
this.currentPage = currentPage; +Qf}&D_
this.beginIndex = beginIndex; *YSRZvD<\
} |nE4tN#J<
/3&MUB*z&y
/** SA7(EJ95
* @return Re&"Q8I.8
* Returns the beginIndex. M*f]d`B
*/ P?S]Q19Q4
publicint getBeginIndex(){ s VHk;:e>x
return beginIndex; sn"z'=ch
} .G#li(NWH
hD=.rDvO
/** bF6J>&]!
* @param beginIndex }wkY`"
* The beginIndex to set. yM~bUmSg
*/ FWA?mde
publicvoid setBeginIndex(int beginIndex){ $1g1Bn
this.beginIndex = beginIndex; C!|LGzs0
} z;!"i~fFK
tj$[szo
/** :AS`1\ C
* @return K8R>O *~
* Returns the currentPage. vd)zvI
*/ Q;J(
5;
publicint getCurrentPage(){ ?xrOhA9
return currentPage; {`Gd
} d$jwh(Ivs
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/** aydNSgu
* @param currentPage a|"Uw
`pX+
* The currentPage to set. g/fpXO\
*/ 2j}DI"|h
publicvoid setCurrentPage(int currentPage){ +FAj30
this.currentPage = currentPage; [q_+s
} _&/ {A|n
2 rr=FJ
/** S>r",S
* @return _bi)d201
* Returns the everyPage. SI=u-'%
*/ NB4O,w
publicint getEveryPage(){ kw@^4n+M
return everyPage;
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} A4cOnG,
HA*L*:0
/** ,T`,OZm
* @param everyPage y?3.W
* The everyPage to set. ,|B-Nq
*/ H#DvCw
publicvoid setEveryPage(int everyPage){ 8'HS$J;C
this.everyPage = everyPage; {eV8h}KIl
} `/ayg:WSU
uINdeq 7|F
/** 0'fswa)
* @return XS">`9o!
* Returns the hasNextPage. kJp~'\b
*/ Ff%V1BH[
publicboolean getHasNextPage(){ -X~mW
return hasNextPage; Cf3!Ud
} qS2Nk.e]o
i*Ldec^
/** k%sH0 9
* @param hasNextPage 2h'Wu
qO
* The hasNextPage to set. BUJ\[/
*/ `}$o<CJ
publicvoid setHasNextPage(boolean hasNextPage){ %KXiB6<4
this.hasNextPage = hasNextPage; {VL@U$'oI
} =I'3C']Z W
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/** !6T"J!F#
* @return ~?AEtl#&"
* Returns the hasPrePage. C=/B\G/.9
*/ {^
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publicboolean getHasPrePage(){ #uw&u6*\q
return hasPrePage; *L$2M?xkY
} Zn'tNt/
uI)twry]@
/** Z0jgUq`r
* @param hasPrePage /}(d'@8p
* The hasPrePage to set. :Ko6.|
*/ ~vF a\7sf
publicvoid setHasPrePage(boolean hasPrePage){ (
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this.hasPrePage = hasPrePage; LmePJ
} AO$AT_s
g4$(%]
/** n%s%i-[5B
* @return Returns the totalPage. hlaN'j
<C
* /.Ak'Vmi
*/ %, kP_[!>Q
publicint getTotalPage(){ :^.wjUI
return totalPage; rNii,_
} FM >ae-L-
[d6!
/** |)29"_Kk5
* @param totalPage jC9us>b
* The totalPage to set. yZ|"qP1
*/ .h7s.p?
publicvoid setTotalPage(int totalPage){ o)AwM"
this.totalPage = totalPage; s|]g@czan
} DAB9-[y+
K>@yk9)vi
} HU i?\4
#]kjyT0
!Qe;oMqy}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?;XEb\Kf
t'rN7.d
个PageUtil,负责对Page对象进行构造: 2Wz8E2.
java代码: _\}'5nmw\
d,V#5l-6
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/*Created on 2005-4-14*/ ^dHQ<L3.*
package org.flyware.util.page; N1c=cZDV
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import org.apache.commons.logging.Log; <Kd(fFe
import org.apache.commons.logging.LogFactory; Q +^&
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/** 1cLtTE
* @author Joa d(T4Kd$r
* CubQ6@,
*/ .$qa?$@
publicclass PageUtil { G<;~nAo?f0
T{k
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4
privatestaticfinal Log logger = LogFactory.getLog <v:VA!]
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(PageUtil.class); N+|NI?R?}
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/** =
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* Use the origin page to create a new page C82_)@96
* @param page `@~e<s`j
* @param totalRecords nT6y6F_e
* @return ,,'jyqD
*/ H}^ '
publicstatic Page createPage(Page page, int <v_=k],W
:v&[!
totalRecords){ SS=<\q#MS
return createPage(page.getEveryPage(), >cu%C s=m
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page.getCurrentPage(), totalRecords); ,ks2&e
} ,=:K&5mCv
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/** ef5)z}B
* the basic page utils not including exception iC
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:Ha/^cC/3
handler &L;ocd$
* @param everyPage BUO5g8m{
* @param currentPage "O&93#8
* @param totalRecords Q`ua9oIJ=
* @return page ^SdF\uk{?6
*/ T*z]<0E]
publicstatic Page createPage(int everyPage, int Xwm3# o.&)
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currentPage, int totalRecords){ lvs
XL
everyPage = getEveryPage(everyPage); hi7_jl6
currentPage = getCurrentPage(currentPage); ToXWFX
int beginIndex = getBeginIndex(everyPage, "yn~axk7
;H_/o+
currentPage); Dyov}y
int totalPage = getTotalPage(everyPage, )dXa:h0RZ
_bFUr
totalRecords); M";qo6
boolean hasNextPage = hasNextPage(currentPage, p4'
.1.@
{VgE07r
totalPage); fE#(M +(<
boolean hasPrePage = hasPrePage(currentPage); ')X(P>
DXFu9RE\{
returnnew Page(hasPrePage, hasNextPage, 51#*8u+L
everyPage, totalPage, RJrz ~,}
currentPage, SK<Rk
n
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beginIndex); qpjY &3SI
} 1Ms[$$b$
/k#-OXP~
privatestaticint getEveryPage(int everyPage){ g 9_ zkGc7
return everyPage == 0 ? 10 : everyPage; ~wvt:E,fC
} Rn1oD3w
.Ro/ioq
privatestaticint getCurrentPage(int currentPage){ LD$5KaOW
return currentPage == 0 ? 1 : currentPage; Z*,e<zNQ
} Av X1*
D -}>28
privatestaticint getBeginIndex(int everyPage, int ~f/|bcep
<Vat@e
currentPage){ Ma YU%h0
return(currentPage - 1) * everyPage; `zd,^.i5~
} vCzZjGBY
*FS8]!Qg
privatestaticint getTotalPage(int everyPage, int `KJ(. m
a:kAo0@":j
totalRecords){ D31X {dJ
int totalPage = 0; VF%QM;I[Rc
!ifU}qFzK
if(totalRecords % everyPage == 0) )H8_.]|
totalPage = totalRecords / everyPage; ;Rrh$Ag
else P}bIp+
totalPage = totalRecords / everyPage + 1 ; LCF}Y{
j]u!;]
return totalPage; =C"[o\]VV
}
q6
CrUn
!b8V&<
privatestaticboolean hasPrePage(int currentPage){ F'bwXb**
return currentPage == 1 ? false : true; -^_m(@A<~
} "F
F$Q#)
_jWs(OmJ
privatestaticboolean hasNextPage(int currentPage, E$d#4x
5E!C?dv(z
int totalPage){ OgQdyU
return currentPage == totalPage || totalPage == ]?9*Vr:P^
nL@'??I1
0 ? false : true; XJ18(Q|w'
} K$"#SZEi
Ayz*2N`%
> I2rj2M#
} u[>"_!T
^Hd[+vAvR
y Zafq"o
_&<n'fK[
GO"`{|o
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 7v: XAU
hFtV\xFK
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 p|>*M\LE#
+8Xjk\Hi
做法如下: I!x.bp~V!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 KX)n+{
L2}\Ah"[
的信息,和一个结果集List: /6x&%G:m#
java代码: 8 Rx@_
l|CM/(99-
["-rDyP
/*Created on 2005-6-13*/ z0"t]4s
package com.adt.bo; <Ap_#
X! d-"[
import java.util.List; Gh;\"Qx
l;?:}\sI=
import org.flyware.util.page.Page; {u'szO}k
o`T.Zaik,
/** X+X:nL.t
* @author Joa yD\q4G
*/ *?)MJ@
publicclass Result { +! 1_Mt6
lriezI
private Page page; |9*Rnm_
~7m`p3W@
private List content; ?<?Ogq"<
XlppA3JON|
/** g~lv/.CnA+
* The default constructor "?"
:
*/ -&+:7t
public Result(){
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super(); ddn
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} u
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7?.uAiM'zT
/** x :SjdT
* The constructor using fields -(vHy/Hz.
* )nUdU
= m
* @param page _c5@)I~
* @param content [2:d@=%.
*/ ZO+RE7f*?c
public Result(Page page, List content){ SN6 QX!3
this.page = page; Ly=.
this.content = content; A95f!a
} ~q>jXi
:;$MUOps
/** E-A9lJWr
* @return Returns the content. Gp9 <LB\,
*/ HQ-[k$d
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publicList getContent(){ wL;OQhI
return content; cVi_#9u"
} ~OD6K`s3
]LE,4[VxRz
/** "~r<ZG
* @return Returns the page. t]xz7VQ
*/ &3vm
@
public Page getPage(){ hY)zKX_r
return page; Q2CGC+
} d59rq<yI
K1
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/** R
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* @param content x{H+fq,M
* The content to set. n:AZ(f
*/ ib,`0=0= O
public void setContent(List content){ 6IqPZ{g9K'
this.content = content; 9Po>laT
5
} 8mX!mYO3c
+3,7 Apj
/** Th_@'UDa
* @param page 7%h;To-<6
* The page to set. p$,7qGST
*/ {O+T`;=)L
publicvoid setPage(Page page){ Laj/~Ru6
this.page = page; 1P)K@j
} pH~\~
} 4LSs WO<@
G^'We6<
g;l K34{
kNuvJ/St
6 (rm%c
2. 编写业务逻辑接口,并实现它(UserManager, 8\J$\Edv
l;-2hZ
UserManagerImpl) ZayJllaq^
java代码: |Iy;_8c
~/^fdGr
!(*&P
/*Created on 2005-7-15*/ m"L^tSD~
package com.adt.service; LWr YKi
XX=OyDLqP
import net.sf.hibernate.HibernateException; 2)EqqX[D
73qE!(
import org.flyware.util.page.Page; QL0q/S1*
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import com.adt.bo.Result; jV%
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;CO qu#(
/** F=\
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* @author Joa r1~W(r.x
*/ `.@udfog^0
publicinterface UserManager { G}U <^]c
uQG|r)
public Result listUser(Page page)throws EH".ki=e
" ILF!z
HibernateException; 4 95Y<x}=
65Z}Hf
} gX"
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c@A.jc
(-ELxshd
RIkIE=+6
java代码: !\ b-Ot(
j32*9
p,=IL_
/*Created on 2005-7-15*/ kB+$Kt<]L
package com.adt.service.impl; o0WwlmB5
ybpOk
import java.util.List; 6TRLHL~B
2UQF:R?LQ
import net.sf.hibernate.HibernateException; olv&K(-ccI
iKq_s5|sW
import org.flyware.util.page.Page; (ot,CpI(I
import org.flyware.util.page.PageUtil; D)MFii1J~
(jKqwVs.:
import com.adt.bo.Result; Az8b_:=
import com.adt.dao.UserDAO; cO:lpsKYQ
import com.adt.exception.ObjectNotFoundException; ;9~YQW@|
import com.adt.service.UserManager; 0L;,\&*u
F]RPM(!5O)
/** tk0m[HN@eV
* @author Joa >QDyG8*
*/ Ztk%uc8_lM
publicclass UserManagerImpl implements UserManager { 23|JgKuA
L1_O!EQ
private UserDAO userDAO; aj|3(2;Kp
,b^Y8_ltoT
/** 5]mH.{$x$?
* @param userDAO The userDAO to set. e@c8Ce|0
*/ Qfp4}a=
publicvoid setUserDAO(UserDAO userDAO){ ^5Y<evjm
this.userDAO = userDAO; 7(5d$ W
} ]prw=rD
E2l"e?AN~
/* (non-Javadoc) h~QQ-
* @see com.adt.service.UserManager#listUser y%|E z
aP (~l_
(org.flyware.util.page.Page) aGWO3Nk
*/ >0 7i"a
public Result listUser(Page page)throws 75>%!mhM
kM-8%a2i
HibernateException, ObjectNotFoundException { vEjf|-Mb9
int totalRecords = userDAO.getUserCount(); R;,5LS&*a
if(totalRecords == 0) shGUG;
throw new ObjectNotFoundException _I)TO_L;
b73}|4v
("userNotExist"); S%H"i
y
page = PageUtil.createPage(page, totalRecords); RJ'za1@z;b
List users = userDAO.getUserByPage(page); "r`2V-E
returnnew Result(page, users); c}v8j2{
} Sj)?!
@Y,t]
} =Crl{Ax
*56j'FX
ka=A:biz
1/bTwzR.g
&R/-~w5
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 qAp<OJ
};rEN`L
询,接下来编写UserDAO的代码: gWro])3
3. UserDAO 和 UserDAOImpl: m,+E5^
java代码: :bo2H[U+
3hkEjR
r}Vr_
/*Created on 2005-7-15*/ Ww~C[8q
package com.adt.dao; +dCR$<e9r
uJ|,-"~F
import java.util.List; Mg0ai6KD
-^np"Jk
import org.flyware.util.page.Page; Rxw+`ru
@WXRZEz
import net.sf.hibernate.HibernateException; <bn|ni|c"
XiV*d06{
/** ;Ym6ey0t
* @author Joa Za,o
*/ 0(C[][a*u
publicinterface UserDAO extends BaseDAO { (g dzgLHy
3 p -SpUvp
publicList getUserByName(String name)throws .: wg@Z
rD6NUS
HibernateException; cEXd#TlY~X
<`q-#-V@
publicint getUserCount()throws HibernateException; w3iX "w
^^V+0 l
publicList getUserByPage(Page page)throws zWN]#W`
0LGHSDb
HibernateException; X+;#^A3
@6[aLF]F
}
aR)UHxvX
*?Oh%.HgF
Mu.tq~b >
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xt@v"P2Ok
java代码: (RUc>Qi
.|:(VG$MfI
~hP]<$v
/*Created on 2005-7-15*/ \HMuVg'Q
package com.adt.dao.impl; pcd?6jh8
V[8!ymi0
import java.util.List; lh\`9F:
uI)z4Z
import org.flyware.util.page.Page; +CQIm!Sp
l7WZ" 6d
import net.sf.hibernate.HibernateException; /w5c:BH
import net.sf.hibernate.Query; %}
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import com.adt.dao.UserDAO; @Rd`/S@
E)'T;%
/** u#ocx[
* @author Joa '*U_!RmQ
*/ _0&U'/cs
public class UserDAOImpl extends BaseDAOHibernateImpl rXrIGgeM
.dc|?$XV
implements UserDAO { hZ>1n&[@
M6[O>z
/* (non-Javadoc) j<?k$8H
* @see com.adt.dao.UserDAO#getUserByName 3E @ &
bHDZ=Ik
(java.lang.String) ZSwhI@|
*/ 25vq#sS]
publicList getUserByName(String name)throws m9 'bDyyK
)Zvn{
HibernateException { *P12d
String querySentence = "FROM user in class !(_qM
r-hb]!t
com.adt.po.User WHERE user.name=:name"; nS!m1&DeD
Query query = getSession().createQuery >)`*:_{
U,<?]h
(querySentence); O/l/$pe
query.setParameter("name", name); M VE:JNm
return query.list(); #E/|WT
} +D h?MQt?
0sq?>$~Kc*
/* (non-Javadoc) Z4k'c+
* @see com.adt.dao.UserDAO#getUserCount() (>\4%(pnD
*/ >(gbUW
publicint getUserCount()throws HibernateException { B.?@VF
int count = 0; 4E$6&,\
String querySentence = "SELECT count(*) FROM ?R@u'4yK
[L2N[vy;
user in class com.adt.po.User"; f 0/q{*
Query query = getSession().createQuery _k)EqPYu@
tac_MtW?
(querySentence); `:gXQmt
count = ((Integer)query.iterate().next UE/iq\a>
fo;^Jg.
()).intValue(); m.yt?`
return count; ,_'Z Jlx
} @
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RHI?_gf&
/* (non-Javadoc) y<ZT~e
* @see com.adt.dao.UserDAO#getUserByPage 4g+o/+6!4
ad<ZdO*h
(org.flyware.util.page.Page) /p{$HkVw
*/ \NL*$SnxP
publicList getUserByPage(Page page)throws q] '2'"k
F@xKL;'N74
HibernateException { |x ir93 |
String querySentence = "FROM user in class 9+'*
2 o5u02x
com.adt.po.User"; z7JhS|
Query query = getSession().createQuery xc?=fv
uF@DJX}>
(querySentence); e$-Y>Dd
query.setFirstResult(page.getBeginIndex()) "2
qivJ
.setMaxResults(page.getEveryPage()); |zp}u (N
return query.list(); @(m?j1!M
} ZY)&Fam}
6 Znt
}
{u$<-W-&
l Ztw[c
_W BWFGj
zE=^}K+
h(FFG%H(
至此,一个完整的分页程序完成。前台的只需要调用 Z"9D1Uk
j-/F*P
userManager.listUser(page)即可得到一个Page对象和结果集对象 YZc{\~d
1{CVd m<9
的综合体,而传入的参数page对象则可以由前台传入,如果用 $btk48a 7
P\2x9T
webwork,甚至可以直接在配置文件中指定。 N}\3UHtO
$*+`;PG-
下面给出一个webwork调用示例: pE]s>Ta
java代码: (+9^)No
o[k,{`M0
Uclta
/*Created on 2005-6-17*/ KCS},X_
package com.adt.action.user; NY%=6><t!
e~G um
import java.util.List; p~<d8n4UH
O<+x=>_
import org.apache.commons.logging.Log; Y-P?t+l
import org.apache.commons.logging.LogFactory; 9{R88f?;
import org.flyware.util.page.Page; (+.R8
MgQb" qx
import com.adt.bo.Result; $$---Y
import com.adt.service.UserService; *qw//W
import com.opensymphony.xwork.Action; bP1]:^ x@W
?_@Mg\Hc
/**
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* @author Joa CQET
*/ 82w=t
publicclass ListUser implementsAction{ cG4$)q;q
wGx*Xy1n<
privatestaticfinal Log logger = LogFactory.getLog q4KYC!b
Z:<6Ck
(ListUser.class); d6g^>}-!t
WTj,9
private UserService userService; Si=u=FI1e
iR{*XE
private Page page; MY z\ R
\
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privateList users; j<-YK4.t
?`=r@
/* F'JceU
* (non-Javadoc) a*{ -r]
* 1y6{3AZm<
* @see com.opensymphony.xwork.Action#execute() 5H/D~hr&
*/ 3/RNStd<L!
publicString execute()throwsException{ ),U>AiF]
Result result = userService.listUser(page); JrwR:_+|
page = result.getPage(); kSU]~x
users = result.getContent(); '>dx~v %
return SUCCESS; m 3"|$0C~
} ??? ;H
Yi#U~ h
/** M>|R&v
* @return Returns the page. McRfEF\
*/ ~|=goHmm[
public Page getPage(){ @x/D8HK2
return page; wT^Q O^.
} Hge0$6l
hH=}<@z
/** 6e:#x:O
* @return Returns the users. Wt9'-"c
*/ 7G
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publicList getUsers(){ @LR :^>&*
return users; 629#t`W\
} bv4G!21]*;
hd_<J]C
/** lb<D,&+
* @param page I@o42% w2
* The page to set. pJ3Yjm[l
*/ Ce!xa\
publicvoid setPage(Page page){ {K >}eO:K
this.page = page; M%qHf{ B
} _*LgpZ-2(
}ujl2uhM
/** .u$o^; z!
* @param users F4
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* The users to set. FR? \H"'x
*/ 2H2Yxe7? -
publicvoid setUsers(List users){ PNhxF C.
this.users = users; [vyi_0[
} >}6V=r3[+
5 p! rZ
/** \ 3HB
* @param userService zpBkP-%}E
* The userService to set. ;A;FR3=)
*/ "vN~7%
publicvoid setUserService(UserService userService){ hYEUiQ
this.userService = userService;
<5:`tC2
} Z<@dM2b)
} /{*0
\`;
Eao^/MKx-
9 Aq\1QC
!OL[1_-4|K
1CpIK$/
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, kNrN72qg
%Ae43
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 :|PgGhW
|%c"Avc
么只需要: z"j]m_mH
java代码: F<LRo}j"9Q
*^Xtorqo
xmBGZ4f%
<?xml version="1.0"?> B"=w9w]
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork XCUU(H
^QTtCt^:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4g^Xe-
]@9ZUtU,;N
1.0.dtd"> 0mi$_Ld+
o2e gNTG
<xwork> IAzi:ct
;kb);iT
<package name="user" extends="webwork- : XaBCF*
|h* rkLY
interceptors"> 5VhJ*^R`y
c%vtg.A
<!-- The default interceptor stack name n,8bQP=&
XAw0Nn
--> xmNs<mz
<default-interceptor-ref lmpBf{~ S
9HBRWh6
name="myDefaultWebStack"/> $v0beN6MG
HGl.dO7NU
<action name="listUser" &$8YW]1M
~zph,bk
class="com.adt.action.user.ListUser"> 6&s"
"J)3
<param /+ Q3JS(
l7vxTj@(-
name="page.everyPage">10</param> AOscewQ
<result ((cRe6
W}aCU~
name="success">/user/user_list.jsp</result> "`Mowp*
</action> qEajT"?
~x6<A\
</package> "#G`F
-cP7`.a
</xwork> (,OF<<OH
^g
N/ 5
\k>1q/T0V
AtYqD<hl:
.-4]FGg3
bd)'1;p
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 U2vM|7]VP
,Aw
Z%
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 RAB'%CY4
P]%)c6Uh
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %=`wN^3t2
z[+Sb;
Eu|O<9U\
S:8 WBY] M
+sFpIiJg
我写的一个用于分页的类,用了泛型了,hoho br%l>Y\"
x".!&5
java代码: !yo@i_1D
Q%!Dk0-)
%_%BbQf
package com.intokr.util; E(g$f.9
FL E3LH
import java.util.List; o8h`9_
$(+#$F<eo+
/** V[2}
* 用于分页的类<br> 4=qZ Z>[t
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 4~i?xo=;v
* Ld?'X=eQ
* @version 0.01 XJe}^k
* @author cheng 8e32NJ^k~
*/ X+kgx!u'y
public class Paginator<E> { 2Og<e|
privateint count = 0; // 总记录数 ,#U[)}im
privateint p = 1; // 页编号 DPr~DO`b
privateint num = 20; // 每页的记录数 RmRPR<vGW
privateList<E> results = null; // 结果 $0XR<D
wDDNB1_E
/** NOFuX9/'w
* 结果总数 apZPHau6h
*/ `!Yd$=*c_&
publicint getCount(){ =z[$o9
return count; %U6A"?To
} DIw9ov>k
\![ p-mW{
publicvoid setCount(int count){ Q?>DbT6
this.count = count; 7#(0GZN9h%
} se=;vp]3a
3 #"!Hg
/** 4 (XV)QR
* 本结果所在的页码,从1开始 qL4s@<|~
* 1YNw=
* @return Returns the pageNo. @Yn+ir0>O
*/ V5' (op /
publicint getP(){ NG_7jZzXA9
return p; 3JEg3|M(
} '0w</g
K[yP{01
/** 4W#DLip9
* if(p<=0) p=1 1gQ_76Yck
* ;Z); k`j
* @param p 9oYE
*/ +ZOKfX
publicvoid setP(int p){ ]>B4
if(p <= 0) 8([ MR
p = 1; c:aW"U
this.p = p; 0:`*xix
} QP/ZD|/ t1
G*_qqb{B
/** V*DD U]0k
* 每页记录数量 ?dPr HSy
*/ .N7<bt@~)
publicint getNum(){ [&g"Z"
return num; >gDeuye
} WLA&K]
q@g#DP+C
/** Dt!
<
* if(num<1) num=1 (eAz
nTU
*/ 7>=
publicvoid setNum(int num){ 0SQrz$y
if(num < 1) pHXs+Ysw+
num = 1; P\WFm
this.num = num; <HtGp6q
} @]!9;?so
6_:I~TTX
/** Fv*Et-8tN5
* 获得总页数 e_"m\e#N
*/ D5!#c-Y-
publicint getPageNum(){ 1_};!5$.
return(count - 1) / num + 1; 1tLEKSo+
} --EDr>'D5P
`NTtw;%Y
/** uW
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* 获得本页的开始编号,为 (p-1)*num+1 3b|=V
*/ ?GlXxx=eV
publicint getStart(){ Si@6'sw
return(p - 1) * num + 1; ]&N>F8.L+
} TB-dV'w
Zl>dBc%
/** f >.^7.is
* @return Returns the results. ,"Fl/AjO
*/ Y'5(exW
publicList<E> getResults(){ 3-&~jm~"
return results; p8 Ao{
} g)R 2V
KK6fRtKv>q
public void setResults(List<E> results){ P*H0Hwn;
this.results = results; S}a]Bt
} @+l=R|
J?EDz,
public String toString(){ 8t. QFze?
StringBuilder buff = new StringBuilder q#@r*hl
,i1BoG
(); ^/6P~iK'
buff.append("{"); T:@7EL
buff.append("count:").append(count); k~gOL#$
buff.append(",p:").append(p); XK\3"`kd
buff.append(",nump:").append(num); C BoCT3@~
buff.append(",results:").append PXqG;o*Q*?
jFJ}sX9]
(results); wZN_YFwQ
buff.append("}"); nzaA_^`mB
return buff.toString(); iPkCuLQ}
} 8\^A;5
!/!ga)Y
} -cijLlz%+
iEZ+Znon
m[KmXPFht1