Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v8A{q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 11yS2D
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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 g|4v>5Y
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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 k:zGv
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分页支持类: %w6lNl
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java代码: 8m)E~6
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package com.javaeye.common.util; W-ECmw(
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import java.util.List; cNqw(\rr
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publicclass PaginationSupport { /?QBMI
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publicfinalstaticint PAGESIZE = 30; :~9F/Jx
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privateint pageSize = PAGESIZE; MT@Uu
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privateList items; 93#wU})
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privateint totalCount; MMUw+jM4
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privateint[] indexes = newint[0]; b~FmX
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privateint startIndex = 0; 5($
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public PaginationSupport(List items, int u@zBE?
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totalCount){ uc;QSVWGy8
setPageSize(PAGESIZE); doaqHri\,
setTotalCount(totalCount); tt>=Vt'
setItems(items); h9J
setStartIndex(0); _26F[R1><~
} ktKT=(F&
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public PaginationSupport(List items, int x;R9Gc[5
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totalCount, int startIndex){ Z?-l-sK
setPageSize(PAGESIZE); ;q$O^r~
setTotalCount(totalCount); 1e^-_Bo6'o
setItems(items); (wIpq<%
setStartIndex(startIndex); ouUU(jj02
} nS1D&;#Y
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public PaginationSupport(List items, int NASRr
)Hy|K1
totalCount, int pageSize, int startIndex){ z '%Vy
setPageSize(pageSize); ?5 d3k%
setTotalCount(totalCount); 5 ERycC y
setItems(items); C zvi':
setStartIndex(startIndex); }mC-SC)oSi
} AHR[i%3W
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publicList getItems(){ #yVY!+A
return items; izi=`;=D^
} zKk2>.
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publicvoid setItems(List items){ 5<ycF_
this.items = items; u|D_"q~+6
} A3N<;OOk
AHhck?M^
publicint getPageSize(){ #X"eg
return pageSize; DP9hvu/85
} YX_p3
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publicvoid setPageSize(int pageSize){ Dl%NVi+n
this.pageSize = pageSize; Pw'3ya8
} O(PG"c
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publicint getTotalCount(){ U.G** v
return totalCount; L%JmdY;
} &a
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publicvoid setTotalCount(int totalCount){ .Eg>)
if(totalCount > 0){ @vaK-&|#$
this.totalCount = totalCount; Vj"B#
int count = totalCount / T!)v9L
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pageSize; eJ#q! <
if(totalCount % pageSize > 0) l7P~_X_)"
count++; fNx3\<~V=
indexes = newint[count]; X] &Q^
for(int i = 0; i < count; i++){ m>'sM1s
indexes = pageSize * (;' ?56
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i; b^\u
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} Ed)t87E
}else{ ><[($Gq`g
this.totalCount = 0; ,P<n\(DQ
} Kuy,qZv!"
} P/?`
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publicint[] getIndexes(){ Q': }'CI
return indexes; -[4Xg!apO
} R1FBH:Iu
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publicvoid setIndexes(int[] indexes){ {ls$#a+d
this.indexes = indexes; YzSUJ=0/
} 8|w_PP1oE
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publicint getStartIndex(){ 0zaE?dA]
return startIndex; `bffw:;%
} =LS?:Mhm
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publicvoid setStartIndex(int startIndex){ -Vk+zEht
if(totalCount <= 0) nqt;Ge
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this.startIndex = 0; &V[m{.
elseif(startIndex >= totalCount) q7C>A`w
this.startIndex = indexes XU .FLNe
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[indexes.length - 1]; uHUicZf.
elseif(startIndex < 0) V7!x-E/
this.startIndex = 0; C9U~lcIS
else{ *S_eYKSl
this.startIndex = indexes Dg4?,{c9W
m#mM2Guxe
[startIndex / pageSize]; !h{qO&ZH=
} }r6SV%]:
} G_g~-[O
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publicint getNextIndex(){ auqM>yx
int nextIndex = getStartIndex() + ao<@a{G
=)(o(bfSKr
pageSize; UfSWdR)
if(nextIndex >= totalCount) j9sf~}D>
return getStartIndex(); nW3`Z1kq})
else ?C6iJnm
return nextIndex; o jzO?z
} vW
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publicint getPreviousIndex(){ 6e$(-ai
int previousIndex = getStartIndex() - lN)U8
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pageSize; T&I*8 R~
if(previousIndex < 0) !j6]k^ra
return0; 67Z|=B!7
else .
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return previousIndex; >z1RCQWju
} O2?ye 4uq
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} eZ
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抽象业务类 tB4- of3+
java代码: a5:Q%F<!
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/** l~wx8
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* Created on 2005-7-12 P}y}IR{6
*/ -@-cG\{
package com.javaeye.common.business; .xuLvNyQr
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import java.io.Serializable; b2.
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import java.util.List; ]L%qfy4
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import org.hibernate.Criteria; |_8-3
import org.hibernate.HibernateException; ,2/qQD n/
import org.hibernate.Session; 6$w)"Rq
import org.hibernate.criterion.DetachedCriteria; y iE[^2Pv
import org.hibernate.criterion.Projections; FJgr=9>
import T+zZOI
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org.springframework.orm.hibernate3.HibernateCallback; .R;HH_
import UHF.R>Ry
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org.springframework.orm.hibernate3.support.HibernateDaoS ?h"+q8&
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upport; Zh]d&Xeq
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import com.javaeye.common.util.PaginationSupport; :f?\ mVS+
0:R}
public abstract class AbstractManager extends .@ZqCH
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HibernateDaoSupport { y.26:c(
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privateboolean cacheQueries = false; 6]rIYc[,
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privateString queryCacheRegion; e'mm4 2
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publicvoid setCacheQueries(boolean snOd
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cacheQueries){ So\(]S
this.cacheQueries = cacheQueries; Q5b?-
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} N&U=5c`Q'
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publicvoid setQueryCacheRegion(String *g]q~\b/;
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queryCacheRegion){ pI|Lt
this.queryCacheRegion = uuHR!
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queryCacheRegion; )uiYu3 I
} Lnbbv
*
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publicvoid save(finalObject entity){ U0q{8 "Pl
getHibernateTemplate().save(entity); LCx{7bN1ro
} O&Q_vY
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publicvoid persist(finalObject entity){ OACRw%J:X{
getHibernateTemplate().save(entity); N|Xx#/
} k{(R.gLZG
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publicvoid update(finalObject entity){ {v+,U}
getHibernateTemplate().update(entity); \:-#,( .V
} S(eCG2gR
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publicvoid delete(finalObject entity){ )1wC].RFYm
getHibernateTemplate().delete(entity); 4eK!1|1
} F0W4B
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publicObject load(finalClass entity, z$$ E7i
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finalSerializable id){ q 9lz
return getHibernateTemplate().load ]l7) F-v
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(entity, id); R7}=k)U?d@
} R)MWO5
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publicObject get(finalClass entity, S.1\e"MfI
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finalSerializable id){ rXc-V},az8
return getHibernateTemplate().get L|.q19b*
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(entity, id); ~A2{$C
} \B) a57
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publicList findAll(finalClass entity){ iz!E1(z(
return getHibernateTemplate().find("from B/.+&AJw
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" + entity.getName()); EjW3_ %
} ~sT/t1Rp
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publicList findByNamedQuery(finalString 0YK`wuZGS
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namedQuery){ gcDo o2RE
return getHibernateTemplate ms2y[b
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().findByNamedQuery(namedQuery); |b"
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} ]=\vl>W
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publicList findByNamedQuery(finalString query, DKw%z8ft|
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finalObject parameter){ IZ+kw.6e
return getHibernateTemplate l?Vm/YXb
ap;?[B~Ga
().findByNamedQuery(query, parameter); n+1!/H=d
} Y|JC+Ee
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publicList findByNamedQuery(finalString query, 5p!X}u]
</!
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finalObject[] parameters){ ^f*}]`S
return getHibernateTemplate 1{D_30sG.
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().findByNamedQuery(query, parameters); eD5:0;X2
} nF$n[:
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publicList find(finalString query){ &c!d}pU}
return getHibernateTemplate().find 8axz`2 `
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(query); !kCMw%[
} b-4gHW
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publicList find(finalString query, finalObject k\->uSU9
b{Srd3
parameter){ .x\fPjB
return getHibernateTemplate().find ZccQ{$0H
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(query, parameter); N6K%Wkz
} X 'D ~#r
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public PaginationSupport findPageByCriteria FyD^\6/x
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(final DetachedCriteria detachedCriteria){ Ip c2Qsa
return findPageByCriteria S%+,:kq
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); >!u@>
} 1K(a=o[Ce
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public PaginationSupport findPageByCriteria &G63ReW7 @
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(final DetachedCriteria detachedCriteria, finalint MtE18m"z
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startIndex){ )gM3,gSS
return findPageByCriteria "s[Y$!#
;/tZsE{
(detachedCriteria, PaginationSupport.PAGESIZE, Qdepzo>E
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startIndex); dzA5l:5
} 5vxKkk&i4l
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public PaginationSupport findPageByCriteria H<tk/\C
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(final DetachedCriteria detachedCriteria, finalint $xx5+A%,
38Rod]\E
pageSize, |GmV1hN
finalint startIndex){ #bRr|`
return(PaginationSupport) z9> yg_Q
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getHibernateTemplate().execute(new HibernateCallback(){ Eu%19s;u
publicObject doInHibernate CR*9-Y93
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(Session session)throws HibernateException { $lJu2omi1
Criteria criteria = &!)F0PN:u
-Vj'QqZ
detachedCriteria.getExecutableCriteria(session); 9a.r(W[9
int totalCount = L|sWSrqd
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((Integer) criteria.setProjection(Projections.rowCount Y-8qAF?SJ]
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()).uniqueResult()).intValue(); Rg:3}T`~n
criteria.setProjection }h+_kRQ
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(null); 2m`4B_g A
List items = F[aow$",+}
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criteria.setFirstResult(startIndex).setMaxResults @(:ah
_ F0qqj
(pageSize).list(); {?a9>g-BW
PaginationSupport ps = d<*4)MRN
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new PaginationSupport(items, totalCount, pageSize, 3F%Qq7v
j
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startIndex); Bjg 21bw^
return ps; 9&'I?D&8
} , N:'Z
}, true); ,gU%%>-_~w
} [V#"7O vl
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public List findAllByCriteria(final 3YY<2<
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DetachedCriteria detachedCriteria){ ;bt@wgY
return(List) getHibernateTemplate ?$O5w*
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().execute(new HibernateCallback(){ Ru%:
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publicObject doInHibernate K;2]c3T
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(Session session)throws HibernateException { 0m5Q;|mH
Criteria criteria = -25#Vh
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detachedCriteria.getExecutableCriteria(session); eO,
return criteria.list(); /)80@
}
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}, true); `I$qMw,@
} ;qI5GQ {
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public int getCountByCriteria(final #vO3*-hs
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DetachedCriteria detachedCriteria){ 1SBc:!2
Integer count = (Integer) qa ![oMKc
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getHibernateTemplate().execute(new HibernateCallback(){ ujcS>XN,1
publicObject doInHibernate fgxsC7P$
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(Session session)throws HibernateException { `R@24 )
Criteria criteria = lY}mrb
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detachedCriteria.getExecutableCriteria(session); ^H+j;K{5,
return @LY 5]og
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criteria.setProjection(Projections.rowCount O$
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()).uniqueResult(); 6'C!Au
} ";~}"Yz?[
}, true); ]\nG1+ta
return count.intValue();
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} H+zn:j@~L
} PMZdz>>T
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用户在web层构造查询条件detachedCriteria,和可选的
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 DT&[W<oN
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PaginationSupport的实例ps。 ,IUMH]D
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ps.getItems()得到已分页好的结果集 hvBuQuk)
ps.getIndexes()得到分页索引的数组 -b@E@uAX/
ps.getTotalCount()得到总结果数 SX}GKu
ps.getStartIndex()当前分页索引 ;hs:wLVa"
ps.getNextIndex()下一页索引 6\86E$f=h
ps.getPreviousIndex()上一页索引 'OGOT0(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 lGB7(
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ^OG^%
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一下代码重构了。 >1ZMQgCG
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我把原本我的做法也提供出来供大家讨论吧: jn\\,n"6
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首先,为了实现分页查询,我封装了一个Page类: VhSKtD1
java代码: xSb/98;
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/*Created on 2005-4-14*/ fJv0 B*
package org.flyware.util.page; %8o(x 0
QBto$!})
/** 3|:uIoR{
* @author Joa ](_(1
* ,h/0:?R
KW
*/ cb%w,yXw
publicclass Page { any\}
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/** imply if the page has previous page */ W&06~dI1!
privateboolean hasPrePage; _;01/V"q6
Q,\lS
/** imply if the page has next page */ KvilGh10
privateboolean hasNextPage; 8gC(N3/E"
MPzqw)_-v
/** the number of every page */ 3UC8iq*
privateint everyPage; 2L<TqC{,-
d+T]EpQJ*
/** the total page number */ n]Dq
privateint totalPage; L&3=5Bf9
Tjs-+$P+
/** the number of current page */ bT{P1nUu
privateint currentPage; \((>i7C
^J%
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/** the begin index of the records by the current #UND'c(5
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query */ l}Xmm^@)
privateint beginIndex; [JAd1%$3
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/** The default constructor */ b}"/K$`Fd
public Page(){ N=I5MQG
i0AC.]4e"
} R&xD|w8UjM
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/** construct the page by everyPage &\p:VF.
* @param everyPage %oor7 -l
* */ g"Ii'JZ?
public Page(int everyPage){ wFqz.HoB
this.everyPage = everyPage; mOX I"q]p
} *znCe(dd
oub4/0tN,~
/** The whole constructor */ jilO% "
public Page(boolean hasPrePage, boolean hasNextPage, Y6N+,FAk+J
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int everyPage, int totalPage, %!.rP
int currentPage, int beginIndex){ Ne9
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this.hasPrePage = hasPrePage; p`d:g
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this.hasNextPage = hasNextPage; ]hf4= gm
this.everyPage = everyPage; rz7yAm
this.totalPage = totalPage; ]`4QJ;#
this.currentPage = currentPage; r*p%e\ 3
this.beginIndex = beginIndex; e@,L~\
} I(7gmCV
shn-Es*
/** e1/|PgT(KM
* @return L0_=R;.<
* Returns the beginIndex. dJ&s/Z/>E
*/ >y8Z{ALQ5
publicint getBeginIndex(){ 3o^V$N.
return beginIndex; 57MoO
} \U-5&,fP
&YMVoyVD
/**
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* @param beginIndex WI~%n
* The beginIndex to set. VmT5?i
*/ L+kS8D<
publicvoid setBeginIndex(int beginIndex){ a0LX<}
this.beginIndex = beginIndex; "Q
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} '+QgZ>q"
# xoFIH
/** (@#Lk"B
* @return mn4;$1~e>H
* Returns the currentPage. ut,"[+J
*/ L%8"d6
publicint getCurrentPage(){ plIx""a^h
return currentPage; 'K"*4B^3
} QA 9vH'
z"vgwOP su
/** >5gzo6j/
* @param currentPage bG&qgbN>
* The currentPage to set. H5%I?ZXw4
*/ Qv=Z
publicvoid setCurrentPage(int currentPage){ a$|u!_)!h
this.currentPage = currentPage; :OZhEBL&b
} U{}7:&As
Z"^@B2v
/** yTvK)4&
* @return YOoP]0'L
* Returns the everyPage. 1M{#"t{6
*/ sI'HS+~pU
publicint getEveryPage(){ 5.E 2fX
return everyPage; OlJj|?z$
} ]a%Kn]HI&2
N~kYT\$b#
/** P3|<K-dFAK
* @param everyPage ujh4cp
* The everyPage to set. &tOD
*/ g !8lW
publicvoid setEveryPage(int everyPage){ yLX#:
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this.everyPage = everyPage;
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} vJ'
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/** x M[#Ah)
* @return H}~^,B2;
* Returns the hasNextPage. ?!66yn
*/ ]mh+4k?b
publicboolean getHasNextPage(){ ]>,|v,i
=
return hasNextPage; ]z%9Q8q'
} 1mV0AE538
6;*(6$;
/** TExlGAHo+O
* @param hasNextPage 2fk
* The hasNextPage to set. !R@4tSu
*/ f*~fslY,o
publicvoid setHasNextPage(boolean hasNextPage){ Ye6O!,R
this.hasNextPage = hasNextPage; *~L]n4-
} t*#&y:RG
I$LO0avvH2
/** jY.%~Y1y
* @return N-|Jj?c
* Returns the hasPrePage. bW|y -GM
*/ O5?Eb
publicboolean getHasPrePage(){ yB1>83!q
return hasPrePage; u2Obb`p S
} ?rDwYG(u]@
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/** xL"%2nf
* @param hasPrePage F)w83[5_d
* The hasPrePage to set. 8IH gsW";
*/ I2T2'_I
publicvoid setHasPrePage(boolean hasPrePage){ "U.=A7r
this.hasPrePage = hasPrePage; AF}"
} _@;N<$&
YLo$n
/** M[{:o/]<
* @return Returns the totalPage. 1aG}-:$t'
* '1
$ ({{R
*/ ]l'ki8
publicint getTotalPage(){ {@%(0d{n}
return totalPage; >cb
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}
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/** h)vTu%J:
* @param totalPage xn8B|axB
* The totalPage to set. LH;G:
*/ ^ym{DSx
publicvoid setTotalPage(int totalPage){ WV
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this.totalPage = totalPage; gi>_>zStv
} aO%FQ)BT
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} Qknc.Z}
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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 )}!'VIe^!
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个PageUtil,负责对Page对象进行构造: G |^X:+
java代码: |GQ$UB
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JrTBe73.]j
/*Created on 2005-4-14*/ fZfiiE~7J
package org.flyware.util.page; 5qEdN
F`.7_D
import org.apache.commons.logging.Log; oZ[ w
import org.apache.commons.logging.LogFactory; QB,ad
2v1&%x:y#
/** -Wk"o?}q
* @author Joa V2%wb\_z
* qEr[fC@x
*/ h';v'"DoW`
publicclass PageUtil { e&4u^'+K
CD[=z)<z{
privatestaticfinal Log logger = LogFactory.getLog
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:q<%wLs
(PageUtil.class); m4>oE|\
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/** @|Bp'`j%J
* Use the origin page to create a new page eE%yo3
* @param page _|:bac8pL
* @param totalRecords H>iZVE
* @return nV*sdSt
*/ iQC&d_#
publicstatic Page createPage(Page page, int *8H;KGe=
9z/_`Xd_
totalRecords){ p|V1Gh<
return createPage(page.getEveryPage(), ZMg9Qt
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page.getCurrentPage(), totalRecords); 0\nhg5]?
} 5yi q#
)#~fS28j
/** !!%nl_I(
* the basic page utils not including exception m(:qZW
Ec*7n6~9
handler {; cB?II
* @param everyPage WC*:\:mh
* @param currentPage e*6` dz@
* @param totalRecords G%jJ>T4
* @return page <" l;l~Y1
*/ , %O3^7i
publicstatic Page createPage(int everyPage, int `f+g A
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currentPage, int totalRecords){ !BuJC$
everyPage = getEveryPage(everyPage); ?Hxgx
currentPage = getCurrentPage(currentPage); q.[[c
int beginIndex = getBeginIndex(everyPage, A!Ct,%
k]9> V@C
currentPage); *js$r+4
int totalPage = getTotalPage(everyPage, W?J[K;<
S_VncTIO
totalRecords); 7d8qs%nA
boolean hasNextPage = hasNextPage(currentPage, S{7ik,Gdg
6x,=SW@4
totalPage); >1pH 91c'
boolean hasPrePage = hasPrePage(currentPage); aq/Y}s?
6 Ok=q:;
returnnew Page(hasPrePage, hasNextPage, |P0L,R
everyPage, totalPage, ~LW%lMy;^|
currentPage, H6S vU
:42;c:8 5
beginIndex); Mqf}Aiqk;
} SH$cn,3F8
`oRs-,d|<
privatestaticint getEveryPage(int everyPage){ 8yz((?LrDh
return everyPage == 0 ? 10 : everyPage; ff./DMDafI
} 02#Iip3t
eEGcio}_I9
privatestaticint getCurrentPage(int currentPage){ T1!Gr!=
return currentPage == 0 ? 1 : currentPage; 3=|2Gs?ut
} #33RhJu5,
~'QeN%qadP
privatestaticint getBeginIndex(int everyPage, int *([)X2A@+
JP,(4h*
currentPage){ iA{jKk=
return(currentPage - 1) * everyPage; r5da/*G/O
} }d\Tk(W
f3>6:(
privatestaticint getTotalPage(int everyPage, int v:Z4z6M-
N?{1'=Om
totalRecords){ pW--^aHu
int totalPage = 0; 1
u_24
.C;_4jE
if(totalRecords % everyPage == 0) ?r E]s!K
totalPage = totalRecords / everyPage; ig_<kj;Vd
else OPt;G,$ta
totalPage = totalRecords / everyPage + 1 ; IgR"euU
J[Yg]6
return totalPage; CC(*zrOd-
} -YjgS/g
ME@6.*
privatestaticboolean hasPrePage(int currentPage){ Y0fO.k#C^
return currentPage == 1 ? false : true; !a&SB*%^I3
} $#ju?B~
SP?U@w%}
privatestaticboolean hasNextPage(int currentPage, N|O]z
+\8 krA
int totalPage){ n$|c{2]=
return currentPage == totalPage || totalPage == .0fh>kQ
9}jq`xSL
0 ? false : true; R~5*#r@f
} SM#S/|.]
CndgfOF
27 145
} O][Nl^dl
[+MX$y
Xz.Y-5)
$K_YC~
2
ssj(Qo
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 DMcxa.Sd!
[kuVQ$)
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 X})Imk7&E
o|;eMO-
做法如下: =Wk/q_.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 e_~fJ
>AzWM
.r
的信息,和一个结果集List: 7}cDGdr
java代码: y-\A@jJC5
<k\H`P
c6Aut`dK
/*Created on 2005-6-13*/ "ryk\}*<
package com.adt.bo; ^L-w(r62<
#;"D)C
import java.util.List; r -q3+c^+
iA3>X-x
import org.flyware.util.page.Page; d=Df.H+3
jWK@NXMH
/** #3Ej0"A@-B
* @author Joa !H1tBg]5
*/ rx6-~0!eI=
publicclass Result { A6NxM8ybn+
BF@5&>E
private Page page; {s8U7rmML
<< ;HY}s
private List content; 7{An@hNh
LZc$:<J<6
/** Yb%-tv:
* The default constructor .-KtB(t
*/ ]KXMGH_
public Result(){ 8L-4}!~C
super(); =%3b@}%HqS
} `e $n$Bh
~3bZ+*H>
/** h^A3 0f_x
* The constructor using fields pFJQ7Jlx
* )jlP
cO-
* @param page x9)aBB
* @param content O b8B
*/ sCF40AoY&
public Result(Page page, List content){ %h" qMs S
this.page = page; {+"g':><
this.content = content; Ki/'Ic1
} 2sqm7th
(/SGT$#8
/** wMz-U- z
* @return Returns the content. v.Xoq
*/ JYwyR++uo
publicList getContent(){ >sQ2@"y)s2
return content; w!WRa8C
} }U%^3r-
.~q)eV
/** fimb]C I|x
* @return Returns the page. ,jRcl!n`
*/ 3a#PA4Ql
public Page getPage(){ nw0L1TP/J
return page; MCk^Tp!
}
n1*&%d'7
?h!t$QQ!M
/** W}XYmF*_?
* @param content `l>93A
* The content to set. -=$% {
*/ BrJ
o!@<
public void setContent(List content){ _)KY
this.content = content; dh^+l;!L
} IV{FH&t^T"
[dj5$l|
/** k]?z~ p
* @param page rQ
* The page to set. %M{k.FE(
*/ Mlv<r=E
publicvoid setPage(Page page){ }xDB ~k
this.page = page; ~{kM5:-iw
} /
l".}S
} a-]hW=[
T&r +G!2
N%9h~G
1$$37?FE
e,f ;
2. 编写业务逻辑接口,并实现它(UserManager, W.A1m4l58R
~{L.f94N
UserManagerImpl) J3B6X 8P'
java代码: =-$!:W~
OlMBMUR:
#B @X
/*Created on 2005-7-15*/ i`prv&
package com.adt.service; YP[LQ>
'nRp}s1^[
import net.sf.hibernate.HibernateException; NJZXs_%>$
n6b3E*
import org.flyware.util.page.Page; [@m[V1D
F`!TV(,bY
import com.adt.bo.Result; c[SU5 66y
HWqLcQ d:P
/** [tUv*jw %
* @author Joa AG]WO8f)
*/ e:N7BZl'c9
publicinterface UserManager { 31~hlp;
wms1IV%;
public Result listUser(Page page)throws 2~f6~\4GL+
I[#U`9Dt
HibernateException; 9Z&?R++?
/ZHO>LNN|
} Kw)KA^KF
~&1KrUu&
*^'wFbaBO
P7z:3o.
~32Pjk~
java代码: 6wPeb~{
jOs
H2^
BBcj=]"_
/*Created on 2005-7-15*/
Dk6?Nwy"
package com.adt.service.impl; (nLKQV 1
tG/aH% 4S
import java.util.List; \}Dpb%^\
D%-{q>F!gf
import net.sf.hibernate.HibernateException; tqK=\{U
XE9)c
import org.flyware.util.page.Page; <}d/v_+pnh
import org.flyware.util.page.PageUtil; sf`PV}a1
;4,'y
import com.adt.bo.Result; M
Hg6PQIB
import com.adt.dao.UserDAO; huz86CO
import com.adt.exception.ObjectNotFoundException; T?>E{1pS
import com.adt.service.UserManager; ! ,@ZQS
UxyY<H~Wx
/** dY8(nQG
* @author Joa _R)&k%i}
*/ q0Xoj__c!A
publicclass UserManagerImpl implements UserManager { 'Q5&5UrBr
c4\C[$
private UserDAO userDAO; MU|{g
5/
)
8Jr1_a
/** ?0{yq>fTu
* @param userDAO The userDAO to set. i^WIr h3a
*/ lzEb5mg
publicvoid setUserDAO(UserDAO userDAO){ >9=:sSQu
this.userDAO = userDAO; NCi>S%pD`<
} H)E^!eo
IV0[!D
/* (non-Javadoc) y_*n9
)Ct
* @see com.adt.service.UserManager#listUser 8W;2oQN7
Zd[OWF
(org.flyware.util.page.Page) nTs/Q V
*/ 3YW=||;|Yg
public Result listUser(Page page)throws p#bhz5&/
%nWe,_PjD
HibernateException, ObjectNotFoundException { ~AQ>g#|%
int totalRecords = userDAO.getUserCount(); z>G;(F2
if(totalRecords == 0) &'s^nn]
throw new ObjectNotFoundException 8V-,Xig;`
ACb/ITu
("userNotExist"); s"i~6})K<$
page = PageUtil.createPage(page, totalRecords); ,t1vb3
List users = userDAO.getUserByPage(page); A[`G^$
returnnew Result(page, users); hT'=VN
} aVwH
P/MM
UmO
} ~].ggcl`w
sK&,):"]R
X"j>=DEX
kh3<V'k]
nLj&Uf&
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @u/H8\.l
yxwW j>c
询,接下来编写UserDAO的代码: /Wu |)tx
3. UserDAO 和 UserDAOImpl: P?
(vW&B
java代码: 3;-^YG
(bv,02
@uM EXP
/*Created on 2005-7-15*/ L,?/'!xV
package com.adt.dao; h*3{6X#(/
R"3
M[^
import java.util.List; 'tm$q/&
g6%Z)5D]!
import org.flyware.util.page.Page; JO=1ivZl
h%TLD[[/jr
import net.sf.hibernate.HibernateException; .wy$-sG81
%v{1#~u
/** Ly7!R$X
* @author Joa F\:(*1C
*/ ,3HcCuT
publicinterface UserDAO extends BaseDAO { ', {7%G9
jJBnDxsA
publicList getUserByName(String name)throws L\e>B>u
y bQP E/9
HibernateException; +}aC-&
/syVGmS'M
publicint getUserCount()throws HibernateException; D. Kqc
6;+jIkkD)
publicList getUserByPage(Page page)throws 5wT>N46UX
}mZVL~|V
HibernateException; yfEb
)\ZzTS
} 7?nJ4x1
3~Qd)j"<
ufrqsv]=
Bu3T/m
KKEN'-3
java代码: ^aF8wbuZ
\?Mf _
[h&BAR/ 2
/*Created on 2005-7-15*/ c*;7yh&%
package com.adt.dao.impl; c0ez/q1S
v+=k-;-
import java.util.List; e;VIL 2|
Kesy2mE
import org.flyware.util.page.Page; s+Q;pRZW{
" xR[mJ@U
import net.sf.hibernate.HibernateException; *hdC?m._
import net.sf.hibernate.Query; <7XT\?%F
,*Z.
import com.adt.dao.UserDAO; HjA_g0u
(qBvoLkF9N
/** ys'T~Cs
* @author Joa @hif$
*/ LA%bq_>f
public class UserDAOImpl extends BaseDAOHibernateImpl u6Je@e_!
--fFpM3EvS
implements UserDAO { 1J}8sG2`
bMKL1+y(
/* (non-Javadoc) QI}E4-s8
* @see com.adt.dao.UserDAO#getUserByName U#
JIs
~AZWds(,N
(java.lang.String) nfdq y)
*/ ` ;)ZGY\
publicList getUserByName(String name)throws o.7{O,v
5$rSEVg9
HibernateException { z42F,4Gk
String querySentence = "FROM user in class &dR=?bz-A
iv&v8;B
com.adt.po.User WHERE user.name=:name"; q,%:h`t\
Query query = getSession().createQuery ? _g1*@pA
hhI)' $
(querySentence); jrMe G.e=D
query.setParameter("name", name); }uY!(4Rw
return query.list(); VDbI-P&c
} P"_$uO( 5x
=ll=)"O
/* (non-Javadoc) EU-]sTJLF
* @see com.adt.dao.UserDAO#getUserCount() ~9\zWRh
*/ r0]4=6U
publicint getUserCount()throws HibernateException { q|.dez'
int count = 0; }{[mrG
String querySentence = "SELECT count(*) FROM 7KjUW\mN2Z
n_u1&a'
user in class com.adt.po.User"; 6oD\-H
Query query = getSession().createQuery k`{7}zxS
+q<B.XxkA
(querySentence); 58V[mlW)O0
count = ((Integer)query.iterate().next TsQU6NNE
a
W%5~3
()).intValue(); d3;qsUh$yv
return count; x=Hndx^
} Q.U$nph\%d
P\nC?!Q%c
/* (non-Javadoc) M*eJ
JY
* @see com.adt.dao.UserDAO#getUserByPage 3oy~=
>vbY<HGt
(org.flyware.util.page.Page) #z'uRHx%=0
*/ S9| a$3K'
publicList getUserByPage(Page page)throws 6Jz^
9uk<&nqx
HibernateException { \]4v_!
String querySentence = "FROM user in class *QGm//b
*^%*o?M~
com.adt.po.User"; zj{r^D$
Query query = getSession().createQuery {eS|j=
%?Y[Bk3p
(querySentence); 1.<q3q
query.setFirstResult(page.getBeginIndex()) _<c$)1
.setMaxResults(page.getEveryPage()); %
ps$qB'
return query.list(); WjSc/3Qy
} "Z=5gj
&opd2
} n(seNp%_
c]-*P7W
eYX5(`c[
ufV!+$C)is
bi4f]^hQz
至此,一个完整的分页程序完成。前台的只需要调用 Z3TS,a1I4
!p/%lU65
userManager.listUser(page)即可得到一个Page对象和结果集对象 8;14Q7,S
(~~w7L
s
的综合体,而传入的参数page对象则可以由前台传入,如果用 "es?=
.
#lsic8]
webwork,甚至可以直接在配置文件中指定。 :Y,BdU
/Ci*Az P
下面给出一个webwork调用示例: U?a6D:~G
java代码: Z6p5*+
}~K`/kvs
u+H;
@
/*Created on 2005-6-17*/ .xhK'}l[
package com.adt.action.user; X1{[}!
B~
S6R
import java.util.List; %V9ZyQg%*
'G\XXf%J
import org.apache.commons.logging.Log; ^~`?>}MJ
import org.apache.commons.logging.LogFactory; ^O(=Vry
import org.flyware.util.page.Page; {--0z3n>
=Z=o#46JY
import com.adt.bo.Result; a,
Q#Dk
import com.adt.service.UserService; ZK;z m
import com.opensymphony.xwork.Action; jHXwOJq
%
(Rt7%{*
/** o2z]dTJ}o
* @author Joa [u}(57DS
*/ 'H5M|c$s
publicclass ListUser implementsAction{ DGW+>\G
;5-r_D;9
privatestaticfinal Log logger = LogFactory.getLog 5tjP6Z`!9`
c~QS9)=E
(ListUser.class); >_OYhgs1w
D:^$4}h
f
private UserService userService; WrPUd{QM
gz2\H}
private Page page; n1
6 `y}
0Wa}<]:^
privateList users; G,Z^g|6
!q"W{P
/* wo_,Y0vfB
* (non-Javadoc) H~ZV*[A`
* sGh(#A0Pt
* @see com.opensymphony.xwork.Action#execute() 2(5ebe[
*/ 1f",}qe;
publicString execute()throwsException{ }_=eT]
Result result = userService.listUser(page); su*Pk|6%
page = result.getPage(); m]i @ +C
users = result.getContent(); kmzH'wktt
return SUCCESS; 3(C\.oRc
} DCqY|4Qc
.ERO|$fv
/** ]Q]W5WDe:
* @return Returns the page. f&v9Q97=
*/ 9zYVC[o
public Page getPage(){
:Gm/
return page; uqz]J$
} SBA?^T
g&/T*L
/** 6aM*:>C"
* @return Returns the users. rZ8`sIWQt
*/ *m?/O}R
publicList getUsers(){ bfo["
return users; lHgs;>U$
} Q.K,%(^;a
cGjPxG;
/** McB[|PmC
* @param page {G?N E
* The page to set. y;/VB,4V
*/ Zd"^</ S
publicvoid setPage(Page page){ :
]C~gc
this.page = page; N('&jHF
} n:MdYA5,m
2eMTxwt*S
/** J!5$,%v
* @param users J:V?EE,\-
* The users to set. *_>Lmm.yh
*/ B)d(TP,>
publicvoid setUsers(List users){ pz"0J_xDM
this.users = users; bygx]RC[
} p/+a=Yo
pK0"%eA
/** *6q5S4 r
* @param userService E>l~-PaZY
* The userService to set. sQkhwMg
*/ oJN#C%r7
publicvoid setUserService(UserService userService){ 7uzkp&+:
this.userService = userService; kc0E%odF.v
} |i++0BU
} Ub6jxib
0_ 88V
(o`{uj{!
x7O-Y~[2
2}8v(%s p
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, |\pbir
#U14-^7
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 3Z1CWzq(
s{1sE)_
么只需要: ` V##Y
java代码: .V,@k7U,V
41&\mx
p,#o<W
<?xml version="1.0"?> ob8qe,_'
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 4:FK;~wM&x
;+ "+3
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \ Yx/(e
%7|9sQ:
1.0.dtd"> `nu''B
H
Ofs<EQ
<xwork> $< JaLS
9 AJ(&qY(
<package name="user" extends="webwork- <7~'; K
A}l3cP;
`#
interceptors"> dkz=CY3p%X
q.;u?,|E/
<!-- The default interceptor stack name s7F.sg
%^jMj2
-->
PUUwv_
<default-interceptor-ref wRVUu)
u A<n
name="myDefaultWebStack"/> RCpR3iC2
4%4 }5UYN
<action name="listUser" ~sh`r{0
`EaLGzw
class="com.adt.action.user.ListUser"> x7Yu I
<param j:v@pzTD
fb~ytl<
name="page.everyPage">10</param> uLV#SQ=bZN
<result {e 14[0U-
YuO.yh_
name="success">/user/user_list.jsp</result> tS6qWtE
</action> Qnsi`1mASr
a^I\ /&aw'
</package> Vh4X%b$TV
rbWP78
</xwork> H:V2[y8\
*_d7E
X9V *UXTc
;>Ib^ov
@J/K-.r
koug[5T5
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 "]}
bFO7C
dl.p\t(1
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。 3ca (i/c
%WjXg:R
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 fb e[@#:
MDn ua
=c\>(2D
(,0(
GBPo8L"9
我写的一个用于分页的类,用了泛型了,hoho 8<QdMkI
;@oN s-
java代码: &OH={Au
Li4zTR|U
W:pIPDx1=!
package com.intokr.util; pOIJH =#
cQ
R]le%(
import java.util.List; k5'Vy8q
p$]3'jw
/** o6.^*%kM'
* 用于分页的类<br> W*2BT
z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 3[Qxd{8r
* T4Pgbop
* @version 0.01 (@fHl=! Za
* @author cheng m;GCc8
*/ )"7iJb<E
public class Paginator<E> { ?^al9D[:lz
privateint count = 0; // 总记录数 Pd_U7&w,5
privateint p = 1; // 页编号 !Dn,^
privateint num = 20; // 每页的记录数 -lY6|79bF
privateList<E> results = null; // 结果 4O^xY
6m
8;JWK3Gv
/** '-Vt|O_Q
* 结果总数 I 5^!y
*/ I;wp':
publicint getCount(){ t.i 8
2Q
return count; -cAo@}v
} _@
qjV~%Sy
286jI7 T
publicvoid setCount(int count){ ,l\-xSM
this.count = count; L>Fa^jq5
} w;4<h8Wn5
4V)kx[j
/** #lL^?|M
* 本结果所在的页码,从1开始 UGV+/zxIM
* ;n*.W|Uph
* @return Returns the pageNo. Yi%;|]
*/ KPKt^C
publicint getP(){ qN9(S:_Px
return p; Kqb#_hm
} y51e%n$
NJWA3zz
/** I-]?"Q7Jz
* if(p<=0) p=1 .ypL=~Rp
* ^ @s1Z7
* @param p Ot_]3:`J~
*/ Y!w`YYKP
publicvoid setP(int p){ z!ZtzD]cb
if(p <= 0) h+g_rvIG*
p = 1; N/"{.3{W
this.p = p; 84& $^lNV
} |4;Fd9q^m
,~N/- 5
/** IL#"~D?
* 每页记录数量 hF~n)oQ
*/ l[0RgO*S
publicint getNum(){ k8&;lgO'
return num; HdUQCugxx:
} Fo5FNNiID
{HltvO%8
/** $w`xvX
* if(num<1) num=1 pP&7rRhw
*/ Qb-M6ihcc
publicvoid setNum(int num){ l*Gvf_UH
if(num < 1) &N^9JxN?8
num = 1; aFX=C>M
this.num = num; uP)'FI
} BUDi&|,
/L
g)i\R;
/** 3w*R&
* 获得总页数 2j[=\K]
*/ JzQ_{J`k
publicint getPageNum(){ 6,8h]?u.
return(count - 1) / num + 1; )4 e.k$X^
} vtg!8u4
x}Eg.S
/** {T$9?`h~M
* 获得本页的开始编号,为 (p-1)*num+1 Cgk<pky1
*/ M6"PX *K
publicint getStart(){ SaO}e
return(p - 1) * num + 1; -V77C^()8d
} iy.p n
G"qvz{*
/** {L{o]Ii?g
* @return Returns the results. _}Ac n$
*/ =7=]{Cx[
publicList<E> getResults(){ oq
Xg
return results; 5uGq%(24
} nfbR
P t
GY'%+\*tj
public void setResults(List<E> results){ #jvtUS \
this.results = results; hR?{3d#x2
} Mq156TL
hn
GZ=
public String toString(){ e'NJnPO
StringBuilder buff = new StringBuilder ~w+c8c8pW
AlaW=leTe
(); ZPLm]I\]
buff.append("{"); AofKw
buff.append("count:").append(count); I5p?
[
buff.append(",p:").append(p); R`qFg/S
buff.append(",nump:").append(num); Qz1E 2yJ
buff.append(",results:").append pI\]6U
?(1y
(results); `g=J%p
buff.append("}"); 6xx ?A>:
return buff.toString(); 6Pl<'3&
} MAR'y8I
Gx/Oi)&/
} ASA,{w]
m.rmM`
+Mb.:_7'