Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 pdu1 kL
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TWP@\ BQ
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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 D
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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 Fh~9(Y#
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分页支持类: `bP`.Wm
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java代码: P`tOL#UeZL
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package com.javaeye.common.util; g#S
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import java.util.List; j{C~wy!J
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publicclass PaginationSupport { e$LC
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publicfinalstaticint PAGESIZE = 30; b8!oZ~K
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privateint pageSize = PAGESIZE; :zW? O#aL-
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privateList items; G|cjI*
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privateint totalCount; Bg|d2,im
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privateint[] indexes = newint[0]; 2dts}G
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privateint startIndex = 0; {i>AQ+z61f
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public PaginationSupport(List items, int MN: {,#d0
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totalCount){ f6r!3y
setPageSize(PAGESIZE); 8vx
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setTotalCount(totalCount); "6,fIsU
setItems(items); Tzd#!Lvm:,
setStartIndex(0); |Iy;_8c
} {$S"Sj
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public PaginationSupport(List items, int lDS y$
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totalCount, int startIndex){ f]*;O+8$LN
setPageSize(PAGESIZE); enk`I$Xx
setTotalCount(totalCount); )xp3
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setItems(items); R0t!y3r&N
setStartIndex(startIndex); ,e'r 0
} :k9T`Aa]
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public PaginationSupport(List items, int D;sG9Hky
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totalCount, int pageSize, int startIndex){ 4KH'S'eR
setPageSize(pageSize); p39$V[*g(
setTotalCount(totalCount); #(
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setItems(items); 4m~y%>
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setStartIndex(startIndex); 2)BO@]n
} W@!qp
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publicList getItems(){ O0}uY:B
return items; 4(8c L?J`0
} UDHOcb
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publicvoid setItems(List items){ RIkIE=+6
this.items = items; 'c~SE>
} j32*9
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publicint getPageSize(){ h<L_ =)lH
return pageSize; a>C;HO
} wn"\@Qv G
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publicvoid setPageSize(int pageSize){ E}Cz(5
this.pageSize = pageSize; qt:B]#j@
} xst-zfkH`
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publicint getTotalCount(){ u.E>d9
return totalCount; H~*N:$C
} F=5+JjrX
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publicvoid setTotalCount(int totalCount){ ;9~YQW@|
if(totalCount > 0){ IAA_Ft
this.totalCount = totalCount; F]RPM(!5O)
int count = totalCount / ,wf_o%'eW
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pageSize; JbEEI(Q>g
if(totalCount % pageSize > 0) 9q ]f]S.L
count++; `*[Kmb\
indexes = newint[count]; PY|zN|
for(int i = 0; i < count; i++){ hq4&<Zr(
indexes = pageSize * P%B|HnG^
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}
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}else{ zMepF]V
this.totalCount = 0; N 75U.;U0
} |keU+De
} xM{[~Kh_x
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publicint[] getIndexes(){ e!=7VEB
return indexes; L@RnLaoQ
} H-t$A, [
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publicvoid setIndexes(int[] indexes){ h0-.9ym
this.indexes = indexes; G%Lt>5*!nE
} TFldYKd/l
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publicint getStartIndex(){ `D3q!e
return startIndex; :xg
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} ;\"5)S
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publicvoid setStartIndex(int startIndex){ b73}|4v
if(totalCount <= 0) q'fOlq
this.startIndex = 0; RJ'za1@z;b
elseif(startIndex >= totalCount) xqdkc^b
this.startIndex = indexes ?Kmz urG
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[indexes.length - 1]; 'RwfW|~6
elseif(startIndex < 0) Qraq{'3
this.startIndex = 0; BgN^].z&
else{ t(<k4 ji,
this.startIndex = indexes /?BTET
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[startIndex / pageSize]; =2*2$
} ;=0-B&+v
} P:J|![
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publicint getNextIndex(){ DI/d(oFv`
int nextIndex = getStartIndex() + J<NpA(@^
<=!t!_
pageSize; EqHToD I3
if(nextIndex >= totalCount) Ag3+z+uS
return getStartIndex(); W rT_7
else nzO-\`40
return nextIndex; Mg0ai6KD
} -^np"Jk
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publicint getPreviousIndex(){ )EYs+7/t
int previousIndex = getStartIndex() - Y q/vym-O5
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pageSize; ys)
if(previousIndex < 0) ;Ym6ey0t
return0; lX.1B&T9Lr
else E690'\)31
return previousIndex; 3 p -SpUvp
} I+Y Z+
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} U e-AF#
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抽象业务类 "1dpv\
java代码: &~<i"
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/** MB5V$toC
* Created on 2005-7-12 >!PM5%G
*/ bTx4}>=5l
package com.javaeye.common.business; Yjy%MR
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import java.io.Serializable; amQiH!}8R
import java.util.List; H>\lE2
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import org.hibernate.Criteria; PTpfa*t
import org.hibernate.HibernateException; "T8b.ng
import org.hibernate.Session; ko{&~
import org.hibernate.criterion.DetachedCriteria; V[8!ymi0
import org.hibernate.criterion.Projections; lh\`9F:
import uI)z4Z
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org.springframework.orm.hibernate3.HibernateCallback; [ P*L`F
import 1JS5 LS
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org.springframework.orm.hibernate3.support.HibernateDaoS 5a5JOl$8
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upport; rWL&-AZQl
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import com.javaeye.common.util.PaginationSupport; ;M+~e~
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public abstract class AbstractManager extends -hK^ *vJ
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HibernateDaoSupport { ju.`c->k"
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privateboolean cacheQueries = false; H_iQR9Ak7
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privateString queryCacheRegion; HS.eK#:N
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publicvoid setCacheQueries(boolean Rs'mk6+
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cacheQueries){ 1<]?@[l<
this.cacheQueries = cacheQueries; ;%AY#b4m
} T[ zEAj
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publicvoid setQueryCacheRegion(String vQ5rhRG)E
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queryCacheRegion){ P$__c{1\
this.queryCacheRegion = Vvn~G.&)
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queryCacheRegion; BgsU:eKe
} Qoz4(~I
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publicvoid save(finalObject entity){ w!UIz[ajI
getHibernateTemplate().save(entity); pSx}:u^am
} P!R`b9_U
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publicvoid persist(finalObject entity){ V4*/t#L/
getHibernateTemplate().save(entity); f 0/q{*
} 9KL)5_6 M
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publicvoid update(finalObject entity){ C7l4X8\w
getHibernateTemplate().update(entity); }F_=.w0
} )uCa]IR
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publicvoid delete(finalObject entity){ G Mg|#DV
getHibernateTemplate().delete(entity); 5N#Sic M
} m4 c2WY6k
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publicObject load(finalClass entity, -+Ox/>k
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finalSerializable id){ qwuA[QkPi
return getHibernateTemplate().load @i>4k
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(entity, id); ZyrVv\'
} |v"&Y
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publicObject get(finalClass entity, opReAU'I
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finalSerializable id){ _BND{MsX
return getHibernateTemplate().get _y9NDLRs8
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(entity, id); g0s*4E
} NV18~5#</
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publicList findAll(finalClass entity){ )tx!BJiZ[
return getHibernateTemplate().find("from 9,wU[=. 0
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" + entity.getName()); dJ7 !je1N*
} ^Zq3K
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publicList findByNamedQuery(finalString $mst\]&;
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namedQuery){ !F)BTB7{<
return getHibernateTemplate :
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().findByNamedQuery(namedQuery); @=6$ImU
} NvJ}|w,Z
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publicList findByNamedQuery(finalString query, 'Fa~l'G7X
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finalObject parameter){ M~*o =t
return getHibernateTemplate DP
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().findByNamedQuery(query, parameter); ByW,YKMy
} k mX:~KMb
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ &}b-aAt
return getHibernateTemplate (x8D ]a
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().findByNamedQuery(query, parameters); 0'II6,:
} \r&9PkHWo
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publicList find(finalString query){ fTV3lyk
return getHibernateTemplate().find T@on
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(query); 7HEUmKb"
} -h#9sl->
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publicList find(finalString query, finalObject V?-OI>
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parameter){ l'#a2Pl
return getHibernateTemplate().find )C#b83
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(query, parameter); k`r`ZA(kQ-
} =o,6iJ^?$m
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public PaginationSupport findPageByCriteria +Am\jsq
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(final DetachedCriteria detachedCriteria){ W< :7z
return findPageByCriteria 4w(#`'I>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); [UYE.$Y#(
} e'5sT#T9 l
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public PaginationSupport findPageByCriteria 5VK.Zs\
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(final DetachedCriteria detachedCriteria, finalint bLyaJ%pa\/
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startIndex){ {*t0WE&1t
return findPageByCriteria Huho|6ohH
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(detachedCriteria, PaginationSupport.PAGESIZE, 7eQc14
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startIndex); ^Z:qlYZ
} *waaM]u
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public PaginationSupport findPageByCriteria 61&A`
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(final DetachedCriteria detachedCriteria, finalint iCh,7I,m
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pageSize, ^z}$'<D9
finalint startIndex){ &bT \4
return(PaginationSupport) C *U,$8j|}
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getHibernateTemplate().execute(new HibernateCallback(){ q#t&\M.U
publicObject doInHibernate S3.76&
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(Session session)throws HibernateException { f|'8~C5I@>
Criteria criteria = @0U={qX
.{
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detachedCriteria.getExecutableCriteria(session); !5=S2<UX
int totalCount = PNhxF C.
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((Integer) criteria.setProjection(Projections.rowCount y6N }R
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()).uniqueResult()).intValue(); _!Ir|j.A
criteria.setProjection ;A;FR3=)
$ {5|{`
(null); !ui:0_
List items =
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criteria.setFirstResult(startIndex).setMaxResults D:vX/mf;7
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(pageSize).list(); 9 Aq\1QC
PaginationSupport ps = $I:&5 o i
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new PaginationSupport(items, totalCount, pageSize, "=3bL>\<
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startIndex); vOi4$I~CJ
return ps; "6
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} ylwh_&>2
}, true); |++\"g
} ^% jk. *
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public List findAllByCriteria(final XX[CTh?O%
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DetachedCriteria detachedCriteria){ s2t9+ZA+s
return(List) getHibernateTemplate hmM2c15T5
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().execute(new HibernateCallback(){ |.Vs(0O
publicObject doInHibernate b,):&M~p
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(Session session)throws HibernateException { [ T!0ka
Criteria criteria = (hFyp}jkk
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detachedCriteria.getExecutableCriteria(session); 5><KTya?=
return criteria.list(); l/g6Tv`w
} .}ePm(
}, true); d}--}&r
} Z,}c)
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public int getCountByCriteria(final kYnp$8
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DetachedCriteria detachedCriteria){ s?~lMm' !
Integer count = (Integer) ]x:>!y
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getHibernateTemplate().execute(new HibernateCallback(){ %8$ldNhV
publicObject doInHibernate q3}WO]TBj
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(Session session)throws HibernateException { /YHAU5N/}
Criteria criteria = =--oH'P=M
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detachedCriteria.getExecutableCriteria(session); "1|\V.>>;
return O"V;otlC
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criteria.setProjection(Projections.rowCount ZYo?b"6A
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()).uniqueResult(); ibn(eu<uW
} M"
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}, true); q!4eVg*
return count.intValue(); ;<N%D=;}@
} $~r_&1
} p` /c&}
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用户在web层构造查询条件detachedCriteria,和可选的 (L'|n*Cr
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $~)YI/b
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PaginationSupport的实例ps。 B<\HK:%{
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ps.getItems()得到已分页好的结果集 gi #dSd1\&
ps.getIndexes()得到分页索引的数组 I#PhzGC@
ps.getTotalCount()得到总结果数 vtF|:*h
ps.getStartIndex()当前分页索引 EaKbG>
ps.getNextIndex()下一页索引 ><i: P*ht
ps.getPreviousIndex()上一页索引 E_-QGE/1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 w9TE E,t;5
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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 r t'pc\|O&
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一下代码重构了。 2Og<e|
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我把原本我的做法也提供出来供大家讨论吧: W^YaC
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首先,为了实现分页查询,我封装了一个Page类: $0XR<D
java代码: wDDNB1_E
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/*Created on 2005-4-14*/ `!Yd$=*c_&
package org.flyware.util.page; =z[$o9
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/** DIw9ov>k
* @author Joa y}1Pc*
* *-(8Z>9
*/ 7#(0GZN9h%
publicclass Page { se=;vp]3a
X m3r)Bm'3
/** imply if the page has previous page */ (7Ln~J*
privateboolean hasPrePage; pGd@%/]AO
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/** imply if the page has next page */ o 3JSh=
privateboolean hasNextPage; "h-ZwL
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/** the number of every page */ Jq?Fi'2F%
privateint everyPage; '<{Jlz(u9
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/** the total page number */ a:Nf+t
privateint totalPage; |]5`T9K@b#
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/** the number of current page */ K[yP{01
privateint currentPage; 0.)q5B`
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/** the begin index of the records by the current XAZPbvG|$
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query */ cx]H8]ch7
privateint beginIndex; ow{J;vFy\
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/** The default constructor */ !e:_$$j
public Page(){ S)?N6sz%
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} vXm'ARj
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/** construct the page by everyPage vi28u xc
* @param everyPage +)LCYDRV7
* */ C_Z/7x*>d
public Page(int everyPage){ 3Ak'Ue
this.everyPage = everyPage; QBh*x/J
} @C%6Wo4l3
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/** The whole constructor */ OG9 '[o`8
public Page(boolean hasPrePage, boolean hasNextPage, !yd]~t
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int everyPage, int totalPage, w' E(9gV
int currentPage, int beginIndex){ w{ ;Sp?Os
this.hasPrePage = hasPrePage; rp+]f\]h
this.hasNextPage = hasNextPage; yf7|/M
this.everyPage = everyPage; Mh{244|o[
this.totalPage = totalPage; _PcF/Gyk
this.currentPage = currentPage; HX)]@qL
this.beginIndex = beginIndex; IXG@$O?y/
} N0%q66]1
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/** a@J/[$5
* @return sY4q$Fq
* Returns the beginIndex. CF
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*/ )|_L?q#w!'
publicint getBeginIndex(){ a?yU;IKJ
return beginIndex; r.lHlHl
} Wm}gnNwA
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/** pKno~jja
* @param beginIndex r@/@b{=
* The beginIndex to set. Q :.i[
*/ Kv2S&P|jXM
publicvoid setBeginIndex(int beginIndex){ YUHiD*
this.beginIndex = beginIndex; SU1N*k#-o
} ?4oP=.
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/** vZW[y5
* @return 8+J>jZ
* Returns the currentPage. r6kJV4I=re
*/ J.'%=q(Sb
publicint getCurrentPage(){ ANNVE},
return currentPage; 9ln=f=
} q#@r*hl
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/** =H3tkMoi2
* @param currentPage #4JLWg
* The currentPage to set. \Z,{De%
*/ <MX
publicvoid setCurrentPage(int currentPage){ k'k}/Hxub
this.currentPage = currentPage; Rj4C-X4=
} vQ]d?Tp
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/** R}cNhZC
* @return ec`re+1r
* Returns the everyPage. +*Z'oC BJ,
*/ h!v<J
publicint getEveryPage(){ $wi4cHh
return everyPage; -cijLlz%+
} zhm 0J-g
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/** JXMH7
* @param everyPage lx=tOfj8
* The everyPage to set. ]%y>l j?Y
*/
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publicvoid setEveryPage(int everyPage){ J8i,[,KcE
this.everyPage = everyPage; ~\8(+qIv%f
} i/skU9
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/** BjagG/sX
* @return gnjhy1o
* Returns the hasNextPage. N'WC!K.e
*/ J{.UUw9Agd
publicboolean getHasNextPage(){ \1LfDlQk)
return hasNextPage; s'oNW
} tv.<pP9-C
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/** #4b]j".P!n
* @param hasNextPage w#[cGaIB
* The hasNextPage to set. 3fp&iz
*/ n=bdV(?4
publicvoid setHasNextPage(boolean hasNextPage){ ;Xy=;Z.]i
this.hasNextPage = hasNextPage; 2,F9P+
} 8*@{}O##
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/** \ ZE[7Ae
* @return kaXq.
* Returns the hasPrePage. pmvd%X\f
*/ ];4!0\M
publicboolean getHasPrePage(){ ~!5=o{wy
return hasPrePage; rv(?%h`
} 4l%1D.3-O
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/** !&>`
* @param hasPrePage u\L}B!
* The hasPrePage to set. ^a_a%ws
*/ pm ,xGo2
publicvoid setHasPrePage(boolean hasPrePage){ 8\!E )M|4
this.hasPrePage = hasPrePage; BjsT 9?6W/
} qSB&Q0T
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/** (nt`8 0
* @return Returns the totalPage. I](a 5i
* C[G+SA1&W
*/ |Rz.Pt6
publicint getTotalPage(){ @anjjC5a~
return totalPage; O"+0 b|
} GaG>0x
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/** %ACW"2#(
* @param totalPage m|B=
* The totalPage to set. 0Zi+x#&d
*/ ;_)~h$1%=
publicvoid setTotalPage(int totalPage){ 3g;,
this.totalPage = totalPage; +Gt9!x}#e
} 1QG q;6\
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} P+}~6}wJE
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 z'_Fg0kR{
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个PageUtil,负责对Page对象进行构造: ^]nLE]M
java代码: 7>__ fQu
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/*Created on 2005-4-14*/ 5tQz!M
package org.flyware.util.page; ;_e9v,
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import org.apache.commons.logging.Log; n jWe^
import org.apache.commons.logging.LogFactory; oNyYx6q:Q
WC`h+SC`.
/** ?gl&q+mv
* @author Joa G/<zd)
* 0bDc
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*/ B5;%R01A
publicclass PageUtil { d"9tP&
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privatestaticfinal Log logger = LogFactory.getLog b4e~Z
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(PageUtil.class); 78uImC*o
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/** 1N8] ~j
* Use the origin page to create a new page UxTLr-db^
* @param page ORs:S$Nt$
* @param totalRecords A_zCSRF,
* @return BB/wL_=:
*/ i D IY|
publicstatic Page createPage(Page page, int I?3b}#&V9
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totalRecords){ 'F/oR/4,
return createPage(page.getEveryPage(), h#hr'3bI1
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page.getCurrentPage(), totalRecords); {r&mNbz
} 6:#o0OeBP
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/** \5r^D|Rp}
* the basic page utils not including exception 9:USxFM
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handler 6(bN*.
* @param everyPage Fvl\.
* @param currentPage 8(%F{&<;
* @param totalRecords G;G*!nlWf
* @return page JY#vq'dl|
*/ X3:z=X&Zd
publicstatic Page createPage(int everyPage, int _-_iw&F
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currentPage, int totalRecords){ qPq]%G*{
everyPage = getEveryPage(everyPage); [<RhaZz
currentPage = getCurrentPage(currentPage); x|~8?i$%
int beginIndex = getBeginIndex(everyPage, /grTOf&
f,TW|Y'{g
currentPage); sN[}B{+
int totalPage = getTotalPage(everyPage, Ay?<~)H
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totalRecords); F?Lt-a+
boolean hasNextPage = hasNextPage(currentPage, c| ^I}
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totalPage); ?Ij(B}D
boolean hasPrePage = hasPrePage(currentPage); f CU]
*#Cx-J
returnnew Page(hasPrePage, hasNextPage, oe|#!SM(
everyPage, totalPage, `q*[fd1u.
currentPage, fs'SCwx
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beginIndex); c4tw)O-X
} 9Y:I)^ek
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privatestaticint getEveryPage(int everyPage){ ZbYC3_7w
return everyPage == 0 ? 10 : everyPage; =0g!Q
} }
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6R n?pe^
privatestaticint getCurrentPage(int currentPage){ 4E^ ?}_$
return currentPage == 0 ? 1 : currentPage; H0af u)$,
} gXdMGO>
0~qc,-)3
privatestaticint getBeginIndex(int everyPage, int /mex{+p>tO
F06o-xH=
currentPage){ @|b-X? `
return(currentPage - 1) * everyPage; eP-|3$
} |UXSUP
@s
+F8{4^w1
privatestaticint getTotalPage(int everyPage, int 5qz,FKx5
mJUM#ry
totalRecords){ <1|[=$w
int totalPage = 0; Tx;a2:6\[
7?Wte&C];p
if(totalRecords % everyPage == 0) ..)J6L5l
totalPage = totalRecords / everyPage; $l]:2!R
else qIi
\[Ugh
totalPage = totalRecords / everyPage + 1 ; _i05'_
PILpWhjL$9
return totalPage; f$C{Z9_SX
} EqW~K@
L
kK
*.
privatestaticboolean hasPrePage(int currentPage){ Ul}RT xJ
return currentPage == 1 ? false : true; k[r^@|
} vE:*{G;Y
keAoJeG,J
privatestaticboolean hasNextPage(int currentPage, EQm{qc;
+fKOX#%
int totalPage){ 6.D|\;9{c
return currentPage == totalPage || totalPage == cpdESc9W
W8d-4')|
0 ? false : true; 5#DMizv6
} bJ^h{]
pe?)AiTZ:
<mn[-
} I&1Lm)W&
YYe G9yR
P.]h`4
xi5"?*&Sb
<V&0GAZ
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。 oYqHl1cs
;,f\Wf"BW
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 XY"b 90
*ub2dH4/
做法如下: m+(Cl#+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 vXJPvh<
9;@p2t*v
的信息,和一个结果集List: %O\@rws
java代码: ^&>B,;Wu
7ch9Pf
;U* /\+*h
/*Created on 2005-6-13*/ /v
8"i^;}
package com.adt.bo; Q~N,QMr)k&
981-[ga`Y
import java.util.List; j"qND=15
Nfa&r
import org.flyware.util.page.Page; 5XKTb
S{=5nR9 j
/** /WN YS
* @author Joa `_\KN_-%Vu
*/ ~5KcbGD~
publicclass Result { `c
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private Page page; k\f
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meX2Y;
private List content; J2z/XHS
%qc_kQ5%
/** $[|(&8+7
* The default constructor ]m+%y+
*/ n5}]C{s'
public Result(){ OC=&!<
super(); Bj@>iw?g'
} ;R?@
D]
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/** ofy"SM
* The constructor using fields CWdsOS=
* T fLqxioqZ
* @param page J"r?F0
* @param content (D>_O$o
*/ ~i.*fL_Y
public Result(Page page, List content){ <],{at` v
this.page = page; H>TO8;5(
this.content = content; Rc1j^S;>
} eCGr_@1
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/** :HY$x
* @return Returns the content. Q#eMwM#~
*/ T[\1=h]
publicList getContent(){ &L8RLSfX
return content; t1 3V>9to
} Z[?n{vD7
-XBZ1q
/** `5Y*)
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* @return Returns the page. f?5>V
*/ /QXUD.(
8
public Page getPage(){ 3xyrWl
return page; z
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} t`o"K
$_.t'8F
/** 5Tl5T&
* @param content 8V:;HY#
* The content to set. <C`bf$ak
*/ EFX2>&mWo8
public void setContent(List content){ [q9B"@X
this.content = content; 0*{(R#
} J^7m?mA
Dz }i-tw+
/** 8C3k:
D[
* @param page tMl y*E
* The page to set. Bu:%trlgV
*/ Ln>!4i+-B)
publicvoid setPage(Page page){ /oPW0of
this.page = page; w#.3na
} "Z@P&jl
} #T7v]@K67
#
-'A
=j
=KPmZ ,/w
w"R<8e=
%-n)L
2. 编写业务逻辑接口,并实现它(UserManager, Xh"9Bcjf
o#qdgZ
UserManagerImpl) ](r}`u%}y
java代码: x{R440"
?}HK!feU
j yHa}OT
/*Created on 2005-7-15*/ !JCs'?A
package com.adt.service; 7By7F:[ b
?|M-0{
import net.sf.hibernate.HibernateException; v-8>@s jy8
)qxt<
import org.flyware.util.page.Page; _U~R
%2 r~
import com.adt.bo.Result; Z ]A
|"6<
XM]m%I
/** Clf$EX;~
* @author Joa b**vUt\
*/ YmljHQP
publicinterface UserManager { PD&e6;rj;
HoQb.Z
public Result listUser(Page page)throws YIe1AF}
ZF7@ b/-me
HibernateException; k3Yu"GY^
8qe[x\,"8
} ?m)<kY
N#u'SGTG
5EtR>Pc
{~apY,3
r5j$FwY
java代码: G$C2?|V)=
?b_E\8'q]
xw*e`9vAe
/*Created on 2005-7-15*/ 9^*RK6
package com.adt.service.impl; %H\b5&
_y
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import java.util.List; t'_EcYNS
2}^=NUM\NX
import net.sf.hibernate.HibernateException; {6u)EJ
Qa2h#0j
import org.flyware.util.page.Page; }IygU 6{G
import org.flyware.util.page.PageUtil; Dw
i-iA_q
0AM_D >fH
import com.adt.bo.Result; FVXsu!R
import com.adt.dao.UserDAO; +yL; ?+s>=
import com.adt.exception.ObjectNotFoundException; zjoo;(?D|
import com.adt.service.UserManager; J6#h~fp v
.X!!dx1<
/** QSaDa@OV
* @author Joa JC'3x9_<z
*/ SQ)BS/8A
publicclass UserManagerImpl implements UserManager { \S h/<z
Tg)F.):
private UserDAO userDAO; 2|k$Vfz
KS_+R@3Z
/** &N.pW=%,N
* @param userDAO The userDAO to set. a?gF;AYk
*/ ~gX1n9_n
publicvoid setUserDAO(UserDAO userDAO){ uyX
%&r
this.userDAO = userDAO; }Y-V!z5z!
} s#7"ZN
#IH9S5B [
/* (non-Javadoc) ~W@dF~r
* @see com.adt.service.UserManager#listUser OP!R>|
99OZK
(org.flyware.util.page.Page) ?e9tnk3
*/ 21!X[)r
public Result listUser(Page page)throws ..yV=idI
$#V'm{Hh
HibernateException, ObjectNotFoundException { ->ZP.7
int totalRecords = userDAO.getUserCount(); >33=0<
if(totalRecords == 0) _`gF%$]b
throw new ObjectNotFoundException Mmz;
uy_
T#*,ME7|m
("userNotExist"); fTEZ@#p
page = PageUtil.createPage(page, totalRecords); yl$Ko
List users = userDAO.getUserByPage(page); hp -|a
returnnew Result(page, users); A^aY-V
} C).\ J !
@Z/jaAjUC
} RZW=z}T+H
J@>|`9T9$
YI0l&'7
NLZ5 5yo$
_4oAk @A
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ^mC~<pP(
:uYZ1O
询,接下来编写UserDAO的代码: .5 E)dU
3. UserDAO 和 UserDAOImpl: ue8 @=}
java代码: )Q1aAS3
*o1US
O n0!>-b,
/*Created on 2005-7-15*/ }/J"/ T
package com.adt.dao; RrxbsG1HP
'$,yV f
import java.util.List; SB%D%Zx6'%
POk5+^
import org.flyware.util.page.Page; =.s0"[%
pwMA,X/{
import net.sf.hibernate.HibernateException; ln_&Ux+l
<Ve0Ph K
/** /@
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* @author Joa Qw_uw QZ)
*/ >!5RY8+
publicinterface UserDAO extends BaseDAO { @Yt394gA%\
<IWg]AJT:
publicList getUserByName(String name)throws C6c*y\O\7
r?)1)?JnHe
HibernateException; r!b>!
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publicint getUserCount()throws HibernateException; cKYvNM
5H Cw%n9
publicList getUserByPage(Page page)throws ,~7~ S"
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HibernateException; 5v oL@w>
Uic
} aMu6{u6
HB#!Dv&'
7 Td
9mkO
S\ak(<X
h,y_^cf
java代码: =WUNBav
HG /fp<[
G#Bm">+
/*Created on 2005-7-15*/ :YLs]JI<
package com.adt.dao.impl; ,$!F,c
N?c~AEk9U
import java.util.List; <f
(z\pi1
st??CX2
import org.flyware.util.page.Page; n^1BtP0!
q-CgXwU
import net.sf.hibernate.HibernateException; ##By!FTP
import net.sf.hibernate.Query; T0A=vh;S
e
6wevK\
import com.adt.dao.UserDAO; ;a|%W4 "
0++RxYFCL
/** `Cd!
* @author Joa )
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*/ j#3IF *"
public class UserDAOImpl extends BaseDAOHibernateImpl q-^{2.ftcx
!]?kvf-3e
implements UserDAO { 6 _V1s1F
'hu'}F{
/* (non-Javadoc) CE{2\0Q
* @see com.adt.dao.UserDAO#getUserByName ;^JMX4[
3\]j4*i!
(java.lang.String) k@9hth2Q
*/ A1;'S<a
publicList getUserByName(String name)throws 7%$3`4i`O
.|CoueH
HibernateException { f#Ud=& >j
String querySentence = "FROM user in class o5RvxGN
Qn$YI9t
com.adt.po.User WHERE user.name=:name"; W
$mw9
Query query = getSession().createQuery d lAb`ne
e{5O>RO
(querySentence); V(;T{HW&
query.setParameter("name", name); IJ5'n
return query.list(); 'h;qI&
} w^cQL%
Mk9J~'C_
/* (non-Javadoc) ^7Z?}tgU
* @see com.adt.dao.UserDAO#getUserCount() )Pubur %,
*/ TPx`qyW
publicint getUserCount()throws HibernateException { R'1j
int count = 0; cSv;HN:
String querySentence = "SELECT count(*) FROM E3{kH
7_'\
Vug[q=i
user in class com.adt.po.User"; Hi2JG{i
Query query = getSession().createQuery @/N]_2@8;
14l6|a
(querySentence);
n gJ{az
count = ((Integer)query.iterate().next #lik: ?
:RDk{^b)
()).intValue(); 5w~ 0Q
return count; bz 7?F!
} OZz/ip-!lc
3QXsr<
/* (non-Javadoc) vz3olHX
* @see com.adt.dao.UserDAO#getUserByPage C \5yo
*Cp:<Mnd
(org.flyware.util.page.Page) f fI=Bt]t
*/ d%L/[.&
publicList getUserByPage(Page page)throws 74NL)|M
./zzuKO8XK
HibernateException { L)<~0GcP
String querySentence = "FROM user in class M%$ITE
<Vt"%C
com.adt.po.User"; Myn51pczl
Query query = getSession().createQuery F(/Ka@
eC<?g
(querySentence); S&&QU#
query.setFirstResult(page.getBeginIndex()) kZ6:=l
.setMaxResults(page.getEveryPage()); iZ/iMDfC
return query.list(); |}8SjZcQW
} UCj<FN `
YuHXm3[
} :}q)]W
@o1#J`rv
z[vu-f9
gw">xt5
M17+F?27M
至此,一个完整的分页程序完成。前台的只需要调用 ;jQ^8S
Ps(oxj7
userManager.listUser(page)即可得到一个Page对象和结果集对象 fGA#0/_`
'"c`[L7Wn
的综合体,而传入的参数page对象则可以由前台传入,如果用 <Mj{pN3
NU'2QSU8
webwork,甚至可以直接在配置文件中指定。 \R-'<kN.*
JSylQ201
下面给出一个webwork调用示例: \|B\7a'4
java代码: U|QP]6v
q-@&n6PEOZ
a-nn[j
/*Created on 2005-6-17*/ Gf+X<a
package com.adt.action.user; 9GT}_
^fb
!?J-Y
import java.util.List; 5-H"{29
j4`+RS+q
import org.apache.commons.logging.Log; 9D,!]
import org.apache.commons.logging.LogFactory; j,9/eZRZ
import org.flyware.util.page.Page; ]
M#LB&Pe
kaoiSL<[6
import com.adt.bo.Result; *5XOYb?'v.
import com.adt.service.UserService; *)?'!
import com.opensymphony.xwork.Action; "~zLG"
UxF9Ko( ]d
/** sV0NDM0
* @author Joa $*:$-
*/ w /PE )xA
publicclass ListUser implementsAction{ nW K7*
II=!E
privatestaticfinal Log logger = LogFactory.getLog dK8dC1@,X;
iv],:|Mbd
(ListUser.class); f;OB"p
/<-=1XJI
private UserService userService; zK_P3rLsS
,_<|e\>~
private Page page; X(.[rC>
.r-Zz3
privateList users; " j_cI-@6
Zz QLbCV
/* ZCBF&.!
* (non-Javadoc) !&.-{ _$
* i6P$>8jBQ-
* @see com.opensymphony.xwork.Action#execute() e^x%d[sU
*/ '.gi@Sr5
publicString execute()throwsException{ $-jj%kS
Result result = userService.listUser(page); DvLwX1(l
page = result.getPage(); +7AH|v8
users = result.getContent(); CY*GCkH
return SUCCESS; i{:iRUC#
} O.\\)8xA
4#:Eq=(W
/** Jk7 Am-.0
* @return Returns the page. paMK]-
*/ rz`"$g+#
public Page getPage(){ Lm<WT*@
return page; x&+&)d
} zMO#CZ t
;|$o z{Ll
/** vl+bc[ i~
* @return Returns the users. mb%U~Na
*/ =:6B`,~C
publicList getUsers(){ QoxQ"r9Wh
return users; MR5[|kHJT
} '{.8tT?tJ
g>gf-2%Uo
/** O(e!Vx{t!
* @param page M)Z!W3
* The page to set. *WFd[cKE
*/ L`wr~E2u
publicvoid setPage(Page page){ Br{(sL0e
this.page = page; P*U^,Jh<
} IGlyx'\_
Y" rODk1
/** ZSD7%gE<D
* @param users oQ*LP{M
* The users to set. tGbx/$Y
*/ \[)SK`cwd
publicvoid setUsers(List users){ VeY&pPQ