Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 JaRsm'SIk~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 G7nhUg
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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 qy3@>
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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 \]u;NbC]
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分页支持类: Y/FPkH4
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java代码: 8XB[CbO
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package com.javaeye.common.util; ~_D.&-xUF
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import java.util.List; 8#7qHT;cx
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publicclass PaginationSupport { Tf86CH=)5
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publicfinalstaticint PAGESIZE = 30; \x}\)m_7M<
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privateint pageSize = PAGESIZE; sF{aG6u
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privateList items; E&P2E3P
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privateint totalCount; =n5'~1?X?
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privateint[] indexes = newint[0]; PW5]+ |#
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privateint startIndex = 0; P0n1I7|
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public PaginationSupport(List items, int n:%4SZn
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totalCount){ by/H:5}7
setPageSize(PAGESIZE); GXtK3YAr
setTotalCount(totalCount); qSc-V`*
setItems(items); vQljxRtW
setStartIndex(0); 7 $e 6H|j@
} B{nwQC b
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public PaginationSupport(List items, int ;miif
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totalCount, int startIndex){ r=H?fTY<3E
setPageSize(PAGESIZE); ?RsrY4P
setTotalCount(totalCount); J-v1"7[2GC
setItems(items); XMrk2]_
setStartIndex(startIndex); aOwjYl[?p
} \Oeo"|
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public PaginationSupport(List items, int &
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totalCount, int pageSize, int startIndex){ M^o_='\bE
setPageSize(pageSize); x}+zhRJ
setTotalCount(totalCount); fST.p|b7
setItems(items); p0Jr{hM
setStartIndex(startIndex); . <"XE7
} =nhY;pY3u
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publicList getItems(){ 8s1nE_3
return items; vYed_'_
} ~3F'X
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publicvoid setItems(List items){ Y[{:?i~9,
this.items = items; Ie.*x'b?y
} 9TW[;P2> )
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publicint getPageSize(){ O3} JOv_
return pageSize; v675C# l(
} ?QOU9"@+B
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publicvoid setPageSize(int pageSize){ PI9,*rOy
this.pageSize = pageSize; {&=+lr_h?
} 0bTj/0G?
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publicint getTotalCount(){ u 272)@R
return totalCount; Bf utmI
} paqGW]
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publicvoid setTotalCount(int totalCount){ Jo5B mh0
if(totalCount > 0){ YM}a>o
this.totalCount = totalCount; @/z\p7e
int count = totalCount / M@Th^yF+8H
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pageSize; *f[5rr4
if(totalCount % pageSize > 0) Mog>W&U
count++; `6Bx8CZ'I
indexes = newint[count]; x4MmBVqp
for(int i = 0; i < count; i++){ 5h5izA'0'
indexes = pageSize * l0qaTpn
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} $1yO Zp5
}else{ lsz3'!%Y)
this.totalCount = 0; VOEV[?>ss
} K./qu^+k
} ;TAj;Tf]H
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publicint[] getIndexes(){ *~#I5s\s!
return indexes; ]auvtm-[
} b] 5weS-<
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publicvoid setIndexes(int[] indexes){ i,6OMB
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this.indexes = indexes; %K6veB{M
} c1#0o)q*7
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publicint getStartIndex(){ +:S`]
return startIndex; cOV j @z
} )~
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publicvoid setStartIndex(int startIndex){ &<A,\M
if(totalCount <= 0) B7%K}|Qg
this.startIndex = 0; 4ud(5m;Rle
elseif(startIndex >= totalCount) D=e*rrL7a
this.startIndex = indexes 4V@%Y,:ee
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[indexes.length - 1]; `3;EJDEdbi
elseif(startIndex < 0) l6 G6H$
this.startIndex = 0; D2$9$xeR
else{ UB$}`39@
this.startIndex = indexes L'+bVP{L
]
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[startIndex / pageSize]; 6/UOzV,[
} `Fd
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} GA^hev
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publicint getNextIndex(){ aI=p_+.h
int nextIndex = getStartIndex() + 6jq*lnA%
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pageSize; IZZAR
if(nextIndex >= totalCount) ^'`b\$km-0
return getStartIndex(); c4H6I~2Na
else =7 l
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return nextIndex; B2;P%B
} uo"<}>iJ
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publicint getPreviousIndex(){ Y~"tL(WfJl
int previousIndex = getStartIndex() - _*mn4n=
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pageSize; AyE*1 FD
if(previousIndex < 0) @{/)k%U
return0; "Z.6@
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else DQG%`-J
return previousIndex; ]Lv P)0=
} S\GWMB!oF
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} #(^<qr
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抽象业务类 4.O) /0sU
java代码: #C9f?fnM
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/** ,/f\
* Created on 2005-7-12 C[7!pd
*/ JwG(WLb:
package com.javaeye.common.business; 0D5Z#iW>1
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import java.io.Serializable; %' DOFiU
import java.util.List; R"cQyG4
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import org.hibernate.Criteria; *AH`ob}
import org.hibernate.HibernateException; 4|x_C-@
import org.hibernate.Session; t&?jJ7 (&8
import org.hibernate.criterion.DetachedCriteria; "f91YX_)
import org.hibernate.criterion.Projections; -.D?Z8e
import v=k+MvX
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org.springframework.orm.hibernate3.HibernateCallback; d{fd5jv;
import }&0LoW/
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org.springframework.orm.hibernate3.support.HibernateDaoS ,Fn;*
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upport; tA(oD4H9
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import com.javaeye.common.util.PaginationSupport; fG\"p
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public abstract class AbstractManager extends ZqclmCi
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HibernateDaoSupport { |lNp0b
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privateboolean cacheQueries = false; Ag8/%a~(
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privateString queryCacheRegion; [N,+mX
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publicvoid setCacheQueries(boolean Tvv>9gS
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cacheQueries){ SdnnXEB7
this.cacheQueries = cacheQueries; )Jt. Z^J<
} mm>l:M TF
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publicvoid setQueryCacheRegion(String WJ8i=MO67
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queryCacheRegion){ OY1bFIE
this.queryCacheRegion = @Ou
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queryCacheRegion; , Q0Y} )
} ]!ai?z%cK#
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publicvoid save(finalObject entity){ aen%
getHibernateTemplate().save(entity); 0moA mfc
} d/
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publicvoid persist(finalObject entity){ V Rv4p5
getHibernateTemplate().save(entity); #Us<#"fC
} 4U dk#
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publicvoid update(finalObject entity){ |X@s {?
getHibernateTemplate().update(entity); vA6`};|
} ;Z*rY?v
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publicvoid delete(finalObject entity){ |uy@v6
getHibernateTemplate().delete(entity); n
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} `)cI^!
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publicObject load(finalClass entity, $~5H-wJ
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finalSerializable id){ j \rGU){
return getHibernateTemplate().load b_sasZo
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(entity, id); dOv\]
} DOyO`TJi
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publicObject get(finalClass entity, '`^~Zy?c
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finalSerializable id){ O.jm{x!m
return getHibernateTemplate().get YT-ua{.^
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(entity, id); g#(+:^3'
} R+.4|1p
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publicList findAll(finalClass entity){ XoD:gf
return getHibernateTemplate().find("from ^?{&v19m
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" + entity.getName()); 4-
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} IhzY7U)}T
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publicList findByNamedQuery(finalString OcUj_Zd
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namedQuery){ .4]XR/I$
return getHibernateTemplate A$p&<#
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().findByNamedQuery(namedQuery); xDeM7L'
} aNry> 2:
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publicList findByNamedQuery(finalString query, i\lvxbp
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finalObject parameter){ !{*yWpZ:
return getHibernateTemplate 8^EWD3N`
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().findByNamedQuery(query, parameter); ;G`]`=s#Lq
} H,
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publicList findByNamedQuery(finalString query, gZ&4b'XS,
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finalObject[] parameters){ W'"hjQ_
return getHibernateTemplate uPl7u1c
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().findByNamedQuery(query, parameters); R@grY:h
} z~f;}`0
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publicList find(finalString query){ Pz*BuL<
return getHibernateTemplate().find >!Gq[i0
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(query); W/A@q o"
} sT =|"H?
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publicList find(finalString query, finalObject @|;[
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parameter){ ]*]*O|w
return getHibernateTemplate().find ;Qy Ew5
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(query, parameter); 8;`B3N7
} lI46
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public PaginationSupport findPageByCriteria <VU-ja*(J
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(final DetachedCriteria detachedCriteria){ 27R4B
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return findPageByCriteria w*"Ii%iA<
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /V0Put
} ]u<U[l-w
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public PaginationSupport findPageByCriteria :*g$@T
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(final DetachedCriteria detachedCriteria, finalint t,TlW^-
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startIndex){ tYMr
return findPageByCriteria ug{sQyLN
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(detachedCriteria, PaginationSupport.PAGESIZE, 6Jy%4]wK
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startIndex); e+#Oj
} jCj8XM{c>
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public PaginationSupport findPageByCriteria iuqJPW^}
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(final DetachedCriteria detachedCriteria, finalint ;s~xS*(C
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pageSize, OWz{WV.
finalint startIndex){ R4)l4rnO
return(PaginationSupport) 6`7`herE}
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getHibernateTemplate().execute(new HibernateCallback(){ ?mV2|;
publicObject doInHibernate OWfB8*4@
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(Session session)throws HibernateException { fFC9:9<
Criteria criteria = aiX4;'$x!
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detachedCriteria.getExecutableCriteria(session); 08@4u
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int totalCount = -A}$5/
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((Integer) criteria.setProjection(Projections.rowCount 4]zn,g?&
\{rhHb\|h
()).uniqueResult()).intValue(); r#j3O}(n
criteria.setProjection
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(null); _eQ-'")
List items = b* n#XTV
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criteria.setFirstResult(startIndex).setMaxResults wBI:}N@.
IN;!s#cl:
(pageSize).list(); UC`sq-n
PaginationSupport ps = CXu$0DQ(
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new PaginationSupport(items, totalCount, pageSize, VAheus
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startIndex); %26HB
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return ps; / E!6]b/
} Z@m5hx&
}, true); V/\`:
} l YdATM(h
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public List findAllByCriteria(final dhg($m
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DetachedCriteria detachedCriteria){ ]LCL?zAzH!
return(List) getHibernateTemplate $D^27q:H
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().execute(new HibernateCallback(){ Z 5wDf+
publicObject doInHibernate @d5t%V\
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(Session session)throws HibernateException { b!QRD'31'j
Criteria criteria = 7
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detachedCriteria.getExecutableCriteria(session); Z@JTZMN_
return criteria.list(); %"E!E1_Sv
} KKg\n^
}, true); .ezko\nU
} b
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public int getCountByCriteria(final Q[!?SSX%
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DetachedCriteria detachedCriteria){ ykx13|iR
Integer count = (Integer) KLj/,ehD
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getHibernateTemplate().execute(new HibernateCallback(){ INCanE`+
publicObject doInHibernate !t)uRJ
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(Session session)throws HibernateException { g p9;I*!
Criteria criteria = +5GC?cW
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detachedCriteria.getExecutableCriteria(session); ncsk(`lo
return (:+Wc^0
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criteria.setProjection(Projections.rowCount qIy9{LF
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()).uniqueResult(); 5}]gL
} `]&'yt
}, true); "|WKK}
return count.intValue(); ~2NTXp
} 8M['-
} !*wd
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用户在web层构造查询条件detachedCriteria,和可选的 Tz(Dhb,
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 =*?XZA)c
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PaginationSupport的实例ps。 ^sJp!hi4=)
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ps.getItems()得到已分页好的结果集 ccW{88II7w
ps.getIndexes()得到分页索引的数组 #\}xyPS
ps.getTotalCount()得到总结果数 dKPx3Y'
ps.getStartIndex()当前分页索引 :'!_PN
ps.getNextIndex()下一页索引 IxWX2yJ]
ps.getPreviousIndex()上一页索引 o:%;AOcl
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 n>lQ:l~
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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 iqTmgE-
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一下代码重构了。 [}l
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我把原本我的做法也提供出来供大家讨论吧: rqM_#[Y?
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首先,为了实现分页查询,我封装了一个Page类: k~1{|HxrE
java代码: - :x6X$=
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/*Created on 2005-4-14*/ xAf?E%_pi
package org.flyware.util.page; %(1y
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/** PiX(Ase
* @author Joa T,4REbm^
* HxShNU
*/ WZ@$bf}f0
publicclass Page { Ed"p|5~
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/** imply if the page has previous page */ p#dYNed]'
privateboolean hasPrePage; ^ s/f.#'
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/** imply if the page has next page */ M`G#cEc
privateboolean hasNextPage; 74~%4
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/** the number of every page */ T
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privateint everyPage; SM`n:{N(
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/** the total page number */ W%}zwQ
privateint totalPage; YR~)07
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/** the number of current page */ <(o) * Zmo
privateint currentPage; z`y^o*qc]
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/** the begin index of the records by the current Z1+1>|-iW
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query */ vQ
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privateint beginIndex; eq36mIo
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/** The default constructor */ j1$s^ -9
public Page(){ wb-_CQ
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} &o)eRcwH`
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/** construct the page by everyPage ohB@ij C!
* @param everyPage ncij)7c)u
* */ ~$ "P\iJ
public Page(int everyPage){ * @'N/W/8
this.everyPage = everyPage; wEb10t,
} >VvA&p71b
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/** The whole constructor */ RZ:=';
public Page(boolean hasPrePage, boolean hasNextPage, &B ^LaRg
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int everyPage, int totalPage, ywbdV-t/
int currentPage, int beginIndex){ 5+iXOs<
this.hasPrePage = hasPrePage; _2S(
*
this.hasNextPage = hasNextPage; ;XGO@*V5T
this.everyPage = everyPage; lyyRyFfQ
this.totalPage = totalPage; )Es|EPCx!
this.currentPage = currentPage; sxU
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this.beginIndex = beginIndex; XXPpj< c
} V3>JZH`
4#wZ#}
/** ,CQg6-[
* @return -|&&lxrwh
* Returns the beginIndex. hxuc4C\J
*/ :pgpE0
publicint getBeginIndex(){ 6n$g73u<=3
return beginIndex; Z {*<Gx
} ?hnxc0~P
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/** E(Y}*.\]#s
* @param beginIndex XlU`jv+
* The beginIndex to set. W v!%'IB
*/ ]*vv=@"`e
publicvoid setBeginIndex(int beginIndex){ 4xD`Z_U
this.beginIndex = beginIndex; 59M\uVWR
} a}/ A]mu
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/** }:hN}*H
* @return /}$D&KwYg
* Returns the currentPage. 7y'2
*/ PFPZ]XI%F
publicint getCurrentPage(){ J`d;I#R%c
return currentPage; ._US8
} +I r
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/** F'9#dR?
* @param currentPage L~>~a1p!
* The currentPage to set. @j=Q$k.GF
*/ jS| 9jg:
publicvoid setCurrentPage(int currentPage){ zP|^) h5
this.currentPage = currentPage; Y4I;-&d's
} 58o'Q
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/** 4S3uzy%
* @return tkKiuh?m
* Returns the everyPage. xy[aZr
*/ K+@R [
publicint getEveryPage(){ o==:e
return everyPage; p5\B0G<m
} )lrmP(C*.a
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/** |WDMyKf6J
* @param everyPage D
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* The everyPage to set. 6$A>%Jtwe
*/ "TP^:Ln
publicvoid setEveryPage(int everyPage){ GEUC<bL+
this.everyPage = everyPage; S<UWv@`U"
} 0;2"X[e
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/** 2*ByVK
* @return HGlQZwf
* Returns the hasNextPage. ~l"]J'jF"H
*/ bn6WvC3?
publicboolean getHasNextPage(){ <3C/t|s
return hasNextPage; , IDCbJ
} =`Lci1#pu}
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/** TNkvdE-S
* @param hasNextPage fuF!3Q
* The hasNextPage to set. 3
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*/ 6w)a.^yx7
publicvoid setHasNextPage(boolean hasNextPage){ xSy`VuSl
this.hasNextPage = hasNextPage; \x;`8H
} Bw25+l Px
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/** YML]pNB
* @return a(oa?OdJ
* Returns the hasPrePage. u4vyj#V
*/ uJ
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publicboolean getHasPrePage(){ iqr/MB,W
return hasPrePage; omzG/)M:O
} K26`wt
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/** 1U6z2i+y
* @param hasPrePage _kXq0~
* The hasPrePage to set. K$/&C:,Q
*/ &$g{i:)Z
publicvoid setHasPrePage(boolean hasPrePage){ ;7E
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this.hasPrePage = hasPrePage; 2xK v;
} <sli!rv
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/** w?:tce
* @return Returns the totalPage. @A'@%Zv-
* 'M!M$<j
*/ Lz{z~xNHW.
publicint getTotalPage(){ !QSj*)V#
return totalPage; ^xm%~
} Mqv[7.|
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/** D0^h;wJ=4+
* @param totalPage /odDJxJ
k
* The totalPage to set. *WaqNMD[%
*/ N> xdX5
publicvoid setTotalPage(int totalPage){ j9xu21'!%
this.totalPage = totalPage; 5yk#(i7C
} zd|n!3;
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} `br$kB
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( 4(,"
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 "fu:hHq
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个PageUtil,负责对Page对象进行构造: ir|c<~_=
java代码: 49.B!DqQW&
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/*Created on 2005-4-14*/ +}R#mco5K
package org.flyware.util.page; -nXlW
}Xvm(
;
import org.apache.commons.logging.Log; %+^Qs\j
import org.apache.commons.logging.LogFactory; zf;sdQ;4
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/** =M=v;
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* @author Joa 8W Etm}
* 10_#Z~aU
*/ 1xI
publicclass PageUtil { YS:p(jtd
=;Dj[<mJ45
privatestaticfinal Log logger = LogFactory.getLog ly:2XvV3~
Wh)!Ha}
(PageUtil.class); f@[qS7ok
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/** O,JS*jXl
* Use the origin page to create a new page GZ^Qt*5 {
* @param page T@A Qe[U'v
* @param totalRecords *:"@
* @return mv7W03
*/ dXfLN<nD>U
publicstatic Page createPage(Page page, int h4#'@%
#a9O3C/MP
totalRecords){ +PS
jBO4!
return createPage(page.getEveryPage(), _b$ yohQ
yzT4D>1,
page.getCurrentPage(), totalRecords); XBoq/kbw!
} 6?'7`p
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/** k!Q{u2
* the basic page utils not including exception eR0$CTSw
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handler .+,U9e:%
* @param everyPage Wy%FF\D.Y
* @param currentPage 6$[7hlE
* @param totalRecords T*nP-b
* @return page zz
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*/ 3)yL#hXg)
publicstatic Page createPage(int everyPage, int vA}_x7}n(
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currentPage, int totalRecords){ mRa\ wEg%
everyPage = getEveryPage(everyPage); oKb"Ky@s
currentPage = getCurrentPage(currentPage); T+^c=[W
int beginIndex = getBeginIndex(everyPage, c]zFZJ6M
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currentPage); A,BYi$
int totalPage = getTotalPage(everyPage, v2_` iwE
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totalRecords); tv26eK
38
boolean hasNextPage = hasNextPage(currentPage, ,J8n}7aI
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totalPage); '%82pZ,?
boolean hasPrePage = hasPrePage(currentPage); Nte$cTjX
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returnnew Page(hasPrePage, hasNextPage, $xWUzg1<U
everyPage, totalPage, Qe{w)e0}`
currentPage, q
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beginIndex); Z"RgqNf
} *~>p;*
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privatestaticint getEveryPage(int everyPage){ X
=%8*_
return everyPage == 0 ? 10 : everyPage; 7f4O~4.[i
} :eSsqt9]9
N#2ldY *
privatestaticint getCurrentPage(int currentPage){ =YTcWB
return currentPage == 0 ? 1 : currentPage; ^sB0$|DU
} 3H`{
A/r
vENf3;o0
privatestaticint getBeginIndex(int everyPage, int M(zZ8#
ZXGi> E
currentPage){ xP!QV~$>
return(currentPage - 1) * everyPage; r*]pL<
} %4f.<gz~r|
~`C_B]3|
privatestaticint getTotalPage(int everyPage, int O`Gq7=X
'It8h$^j
totalRecords){ @0 /qP<E
int totalPage = 0; -sfv"?
"L:4 7!8
if(totalRecords % everyPage == 0) oFf9KHorW
totalPage = totalRecords / everyPage; p |1u,N
else h='F,r5#2
totalPage = totalRecords / everyPage + 1 ; #
)y/aA
[ r8 ZAS
return totalPage; U!`iKy-
} )+hV+rM jp
Yu>DgMW
privatestaticboolean hasPrePage(int currentPage){ msM1K1er
return currentPage == 1 ? false : true; |PlNVd2
} Hddc-7s
~y2zl
privatestaticboolean hasNextPage(int currentPage, >a,D8M?
]Ob|!L(
int totalPage){ u;gO+)wqv
return currentPage == totalPage || totalPage == ##*]2Dy
G %6P`:
0 ? false : true; [104;g <
} a9z#l}IQ
m^G(qoZ]
~e 1l7H;
} b.@a,:"
=i&,I{3
>
'hM"4f
6e B;
8.#{J&h
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。 iBd6&?E?<
%^pi
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 1J4Pnl+hN
-(8I ?{"4i
做法如下: :t{~Mi=T
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]MV8rC[\
LWN{
的信息,和一个结果集List: jb-kg</A
java代码: B-R#?Xn:!I
sa(.Anmlj
r8Mx+r
/*Created on 2005-6-13*/ fq]PKLW'
package com.adt.bo; RhH1nf2UR
{K]5[bMT
import java.util.List; {O^u^a\m
|4Q*4s
import org.flyware.util.page.Page; 9)ALJd,M
)ODF6Ag
/** &$F<]]&
* @author Joa Jpj=d@Of70
*/ #_@cI(P
publicclass Result { 3KkfQ{
xi=ApwNj
private Page page; pn
gto
_*fNa!@hY
private List content; ~,b^f{7`!
CwA_jOp
/** ViPC Yt`of
* The default constructor \=AA,Il
*/ 'J|)4OG:
public Result(){ $(aq;DR
super(); _1p8(n
} HYmC3
l%0bF9\
/** " B#|C'
* The constructor using fields QO/0VB42
* 50W+!'
* @param page d,b4q&^X8
* @param content 5^u$zfR
*/ `hi=y BO
public Result(Page page, List content){ <+i(CGw
this.page = page; $zMshLT
this.content = content; gBm'9|?
} B7C3r9wj
sjr,)|#[
/** ,50
* @return Returns the content. :8A+2ra&
*/ Ey&H?OFiP
publicList getContent(){ elOeXYO0
return content; G%<}TI1}
} Nr~$i% [
,#A(I#wL~
/** Ymk?@mV4
* @return Returns the page. h:YD$XE
*/ \k.`xG?
public Page getPage(){ N+|NI?R?}
return page; GM%+yS}(P
} n|w+08c"
1F^Q* t{
/** 9-KhJq%
* @param content B `~EA] d
* The content to set. ^Xk!wJ
*/ g* q#VmE
public void setContent(List content){ 2bp@m;g$
this.content = content; LL^KZ-
} 6#?T?!vZ
K}~$h,n
/** ;b$P*dSG}
* @param page Dqx#i-L23
* The page to set. _ E;T"SC
*/ Zv u6/#
publicvoid setPage(Page page){ XO <wK
this.page = page; Z*%;;&?
} m1"m KM
} yB b%#GW
liKlc]oM
eUyF<j
Jl
Do_}
Kc MzY
2. 编写业务逻辑接口,并实现它(UserManager, nw+~:c
Xn6#q3;^|
UserManagerImpl) A6N6e\*
java代码: xY^sC56Z
`fu_){
Gm=qn]c
/*Created on 2005-7-15*/ 9wgB JJl7
package com.adt.service; -Zt!H%U
RZOK+!H:
import net.sf.hibernate.HibernateException; i"2OsGT
e7vm3<m4
import org.flyware.util.page.Page; 4CNrIF@
D*XrK0#Z`
import com.adt.bo.Result; QQ*sjK.(
51#*8u+L
/** $
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* @author Joa p@m0Oi,=
*/ bz4Gzp'6k
publicinterface UserManager { Hq3|>OqC2Q
g 9_ zkGc7
public Result listUser(Page page)throws Rn1oD3w
.Ro/ioq
HibernateException; '%N?r,x
C
b+rxin".
} b/SBQ"B%
jk AjYR .
m5\T,
hnnB4]c
V>@[\N[
java代码: U&!TA(Yr
YB#fAU
=$>=EBH,cm
/*Created on 2005-7-15*/ (I[_}l
package com.adt.service.impl; 615Ya<3f8
DiC z%'N
import java.util.List; H?$dnwR
uZqL'l+/y
import net.sf.hibernate.HibernateException; B=_w9iVN
t*{L[c9.Uq
import org.flyware.util.page.Page; +&GV-z~o
import org.flyware.util.page.PageUtil; #NS|9jW
6x+ujUBkK
import com.adt.bo.Result; =~D? K9o
import com.adt.dao.UserDAO; iSW2I~PD
import com.adt.exception.ObjectNotFoundException; d
t/AAk6
import com.adt.service.UserManager; 0YH5B5b
=7Ln&tZ
/** }0'=}BE
* @author Joa 3]Z1kB
*/ N5
ME_)
publicclass UserManagerImpl implements UserManager { L\:|95Yq
VUb>{&F[
private UserDAO userDAO; q6zVu(
7CIN!vrC|1
/** /x VHd
* @param userDAO The userDAO to set. @CprC]X
*/ l45/$G7
publicvoid setUserDAO(UserDAO userDAO){ LUOjaX
this.userDAO = userDAO; JGs:RD'
} --yF%tRMP
j3j?2#vR
/* (non-Javadoc) ]l,BUf-O
* @see com.adt.service.UserManager#listUser vygzL U^
' \JE>#
(org.flyware.util.page.Page) GO"`{|o
*/ 7v: XAU
public Result listUser(Page page)throws Y.^L^ "%dF
p|>*M\LE#
HibernateException, ObjectNotFoundException { +8Xjk\Hi
int totalRecords = userDAO.getUserCount(); I!x.bp~V!
if(totalRecords == 0) |/Nh#
throw new ObjectNotFoundException (q)}`1d'
eYOY
("userNotExist"); z.vQ1~s
page = PageUtil.createPage(page, totalRecords); C @(@n!o:!
List users = userDAO.getUserByPage(page); Z
3BwbH
returnnew Result(page, users); z@*E=B1L
} Kv_2=]H
`Os=cMR
} bI):-2&s}
wu
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i:lc]B
0PzSp ]
qu=~\t1[6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 $?= $F
^q7V%{54
询,接下来编写UserDAO的代码: p`tz*ewC
3. UserDAO 和 UserDAOImpl: %~rEJB@{
java代码: *x36;6~W;
Llfl I
\)PB p
/*Created on 2005-7-15*/ v{u3[c
package com.adt.dao; -hd
L.n@;*
import java.util.List; ]'.qRTz'\t
\CB^9-V3
import org.flyware.util.page.Page; !np_B0`
l6M?[
import net.sf.hibernate.HibernateException; ,=/9Ld2w9
,Py\Cp=Dw
/** Sd+5Uf`
* @author Joa qv!(In>u
*/ K#3^GB3P
publicinterface UserDAO extends BaseDAO { 7 N}@zPAZ
7Cz~nin>7
publicList getUserByName(String name)throws 26V6Y2X
T(!1\ TB
HibernateException; *zrT;jG
a>4/2#J
publicint getUserCount()throws HibernateException; Dri6\/0
u[a-9^&g
publicList getUserByPage(Page page)throws I?T
!
{^]qaQ[5N
HibernateException; UZdnsG7
hf`y_H+\7
} WowKq0sn
N,`@Q7
h ldZA
xP8/1wd.
0h-NT\m
java代码: gtKih
O,$*`RZpx
fB2ILRc
/*Created on 2005-7-15*/ ak 7%
package com.adt.dao.impl; \XDiw~0
l\_!oa~
import java.util.List; ?1Nz
,Lc$
kQ\GVI11?
import org.flyware.util.page.Page; ]TvMT
j.M]F/j
import net.sf.hibernate.HibernateException; 757&bH|a
import net.sf.hibernate.Query; l)r\SE1
y-pdAkDh
import com.adt.dao.UserDAO; :zW? O#aL-
Z$z-Hx@%
/** [* xdILj
* @author Joa 7F`\Gz_2
*/ qlhc"}5x }
public class UserDAOImpl extends BaseDAOHibernateImpl fTxd8an{
FB k7Cn!
implements UserDAO { '4,?YcZ?S
Q Xd`P4a
/* (non-Javadoc) (Mc{nFqS
* @see com.adt.dao.UserDAO#getUserByName !t% 1G.
P|NGAd
(java.lang.String) 5BrN
uR$
*/ ju2H0AQ
publicList getUserByName(String name)throws `E~"T0RX
Y3@+aA
HibernateException { ~/^fdGr
String querySentence = "FROM user in class !(*&P
m"L^tSD~
com.adt.po.User WHERE user.name=:name"; [REH*_
Query query = getSession().createQuery ("`"?G
d=1\= d/K
(querySentence); =svFw&q"
query.setParameter("name", name); JMAdsg/
return query.list(); R0t!y3r&N
} &XNt/bK-?
FQek+[ox
/* (non-Javadoc) uc9h}QJ*
* @see com.adt.dao.UserDAO#getUserCount() 9>{fsy
*/ 'IU3Xu[-.
publicint getUserCount()throws HibernateException { G}U <^]c
int count = 0; uQG|r)
String querySentence = "SELECT count(*) FROM EH".ki=e
S @[]znH
user in class com.adt.po.User"; %
J\G[dl
Query query = getSession().createQuery W@!qp
UVDMYA0
(querySentence); + 149 o2
count = ((Integer)query.iterate().next 7\@c1e*e
IlJ"t`Z9)
()).intValue(); :1d;jx>
return count; y,?=,x}o#
} >4g!ic~O
\7\sx:!$
/* (non-Javadoc) c{^1`(#?
* @see com.adt.dao.UserDAO#getUserByPage =2q#- ,t
S6bW
r0XR
(org.flyware.util.page.Page) rL<N:@HL
*/ <ppdy,j:
publicList getUserByPage(Page page)throws 4{>r_^8
s<*+=aIfu
HibernateException { e;v7!X
String querySentence = "FROM user in class dPO"8HQ
CLND[gc
com.adt.po.User"; #-%D(=&I
Query query = getSession().createQuery M|nLD+d~8
E2|M#Y
(querySentence); Av.`'.b
query.setFirstResult(page.getBeginIndex()) @de ZZ
.setMaxResults(page.getEveryPage()); pZ Uy (
return query.list(); ts=D
} }:?*n:g5
DXJw)%G
w
} X$<pt,}%
U_jW5mgsG
Mn5(Kw?o2J
yR5XcPoKI
}
e w{WD
至此,一个完整的分页程序完成。前台的只需要调用 \HxF?i "
RZEq@q
userManager.listUser(page)即可得到一个Page对象和结果集对象 zMepF]V
a|TUH+|
的综合体,而传入的参数page对象则可以由前台传入,如果用 |keU+De
?121 as}z
webwork,甚至可以直接在配置文件中指定。 ,7$&gx>2&
}S"gZ6
下面给出一个webwork调用示例: Q>[{9bI4QP
java代码: >'n[B
AK
lra$
46M=R-7=
/*Created on 2005-6-17*/ qo:Zc`t(R
package com.adt.action.user; {^
BZ#)m|
zEjl@Kf
import java.util.List; */~|IbZ`o
[#wt3<d`)
import org.apache.commons.logging.Log; 3N]ushMO
import org.apache.commons.logging.LogFactory; b+Sj\3fX
import org.flyware.util.page.Page; ql%K+4@
i=5!taxu}E
import com.adt.bo.Result; ?Kmz urG
import com.adt.service.UserService; NI/'SMj%
import com.opensymphony.xwork.Action; @Y,t]
=Crl{Ax
/** *56j'FX
* @author Joa J_a2DM6d
*/ 51%Rk,/o
publicclass ListUser implementsAction{ *s, bz.[
nVlZ_72d
privatestaticfinal Log logger = LogFactory.getLog 4]}d'x&
yC@PMyE]
(ListUser.class);
H.hKh
"#36-
private UserService userService; 4iSN.nxIZ
{%6
'|<`[
private Page page; uih8ZmRt
lhQMR(w^
privateList users; Nnn~7
,nog6\
/* 5k=04=Iyh#
* (non-Javadoc) G(A7=8vW
* Y8}y0]V
* @see com.opensymphony.xwork.Action#execute() 9k4z__K e
*/ p Dg!Cs
publicString execute()throwsException{ io"NqR#"v
Result result = userService.listUser(page); zp4@T)
page = result.getPage(); ;B<rw^h5
users = result.getContent(); +
S5uxO
return SUCCESS; Tq^B>{S"
} (^T}6t3+4
{OQ)Np!
/** ;
p+C0!B2
* @return Returns the page. s!W{ru
*/ {y|.y~vW
public Page getPage(){ F:Vl\YZ
return page; , iEGf-!k
} 8~!h8bkC
dr8Q>(ZY
/** 7h.[eMLPB
* @return Returns the users. iyR5mA
*/ g}?39?o4
publicList getUsers(){ 8eCh5*_$
return users; amQiH!}8R
}
'mv|6Y
_x-2tnIxXv
/** $/u.F;
* @param page )+)qFGVz
* The page to set. ~urk
Uz
*/ ;Srzka2
publicvoid setPage(Page page){ e*<pO@Uy
this.page = page; nbw8YO(=
} wd,6/5=lh
t[({KbIy
/** / H GPy
* @param users Qm[ ) [M
* The users to set. p-oEoA
*/ AHa]=ka>
publicvoid setUsers(List users){ D1]?f`
this.users = users; 8XfOMf~d`
} svCm}`
EAs^i+/
/** RR`\q>|
* @param userService 1mv5B t
* The userService to set. fTy{`}>
*/ pm}_\_
publicvoid setUserService(UserService userService){
1[Q~&QC
this.userService = userService; n>o=RQ2
} _Fkb$NJ"]Q
} us#ji i.<
%@I= $8j
ip|l3m$ Mi
=m;cy0))
HT_nxe`E
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, .L)j
ql%
eH;{Ln
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 C]zG@O!
h-03]M#8=
么只需要: pfMmDl5|
java代码: N]I::
Vvn~G.&)
<P5 7s+JK
<?xml version="1.0"?> I0bkc3
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork
tB0f+ wC
SphP@J<ONW
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w\JTMS$
&61h*s
1.0.dtd"> -9 |)O:
) C#>@W
<xwork> UJ)(Sw
OQ3IkE`G
<package name="user" extends="webwork- b\SB
o^d
interceptors"> m7cG]a~a
fo;^Jg.
<!-- The default interceptor stack name ?,r}@89pY
Qj9'VI>&
--> @
&GA0;q0t
<default-interceptor-ref tv9 R$-cJ
6(B[(Af
name="myDefaultWebStack"/> >Qf`xUZ
#%/0a
<action name="listUser" 'V4B{n7h
qwuA[QkPi
class="com.adt.action.user.ListUser"> No'Th7=|S
<param xy^z_`
wA";N=i=
name="page.everyPage">10</param> xqj@T^y
<result E**Hu 9
_ o6Zj1p
name="success">/user/user_list.jsp</result> ib(4Y%U6~
</action> 7]
>z e
P.Qz>c^-C
</package> )9{!=k
D'
h%.
</xwork> Q/l388'
xf3/J{n3
1[(/{CClB
LII4sf]
XAUHF-"WE
Oz5Ze/HBN
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 E>1%7"
i<
jGn2QL
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 N}\3UHtO
AYoLpes
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 o[k,{`M0
?,UO$#Xm
tf{o=X.)
p~<d8n4UH
TxmKmZ u
我写的一个用于分页的类,用了泛型了,hoho bSk)GZyH\d
MgQb" qx
java代码: K]>X31Ho
#D Oui]
4nD U-P#f
package com.intokr.util;
Wo/LrCg
?[hkh8|
import java.util.List; 6z1>(Za7>
xY`$j'u
/** WTj,9
* 用于分页的类<br> h~.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> w4;1 ('
* hR~~k~84
* @version 0.01 $McbVn)~f
* @author cheng I:o.%5)
*/ @l@erCw@
public class Paginator<E> { =.6JvX<d1*
privateint count = 0; // 总记录数 ;
Ne|H$N
privateint p = 1; // 页编号 E3 aj
privateint num = 20; // 每页的记录数 KOVR=``"/
privateList<E> results = null; // 结果 4w(#`'I>
8Rd*`]@[pk
/** (-hGb:
* 结果总数 PG'+vl
*/ kTS#>uS
publicint getCount(){
m7.6;k.
return count; +{H0$4y
} )\fLS d
P~ODd(
publicvoid setCount(int count){ c>yqq'
this.count = count; //-;uEO
} </)HcRj'e
M%1wT9
/** (b;*8
* 本结果所在的页码,从1开始 "1>48Z-UC
* hd_<J]C
* @return Returns the pageNo. ^n<o,K4\}
*/ T8-,t];i
publicint getP(){ -gy@sSfvkv
return p; K_CE.8G&{
} 4{Af 3N
qI5`:PH%n
/** ibQN
p Iz
* if(p<=0) p=1 M}xyW"yp
* C *U,$8j|}
* @param p 3YJa3fflK
*/ q#t&\M.U
publicvoid setP(int p){ )XoIb[s"
if(p <= 0) xPorlX)zW
p = 1; si`h(VD9w
this.p = p; )CUB7D)=
} -)$5[jM]
*MZa|Xy
/** `w#p8vR
* 每页记录数量 ?Y\hC0a60
*/ $ {5|{`
publicint getNum(){ )|`|Usn#[
return num; Mib<1ZM
} Eao^/MKx-
>`=<(8bu
/** {<y.G1<.
* if(num<1) num=1 :|PgGhW
*/ ylwh_&>2
publicvoid setNum(int num){ GLE"[!s]f
if(num < 1) k{-#2Qz
num = 1; XCUU(H
this.num = num; hmM2c15T5
} R.$1aqA}
{ bD:OF
/** Auk#pO#
* 获得总页数 qM8"* dL
*/ b[os0D95
publicint getPageNum(){ ~"}o^#@DwJ
return(count - 1) / num + 1; m)Sdogt_
} _fE$KaP
3T84f[CFJ
/** \zM3{{mV/
* 获得本页的开始编号,为 (p-1)*num+1 4"~l^yK
*/ QP:|D_k
publicint getStart(){ SKeX~uLz
return(p - 1) * num + 1; nC(<eL
} \^]*T'>b
>Pf\"%*
/** z6x`O-\
* @return Returns the results. !@4 i:,p@
*/ U2vM|7]VP
publicList<E> getResults(){ ~Y 3X*
return results; "xV0$%
} Eu|O<9U\
0I['UL^!F
public void setResults(List<E> results){ ^\C Fke=
this.results = results; nN5fP<H2x
} _:7:ixN[Ie
><i: P*ht
public String toString(){ B!1Bg9D
StringBuilder buff = new StringBuilder p-XO4Pc6
Pmdf:?B
(); j06qr\Es
buff.append("{"); M2pFXU?]
buff.append("count:").append(count); Yan}H}Oq
buff.append(",p:").append(p); 1\ Gxk&
buff.append(",nump:").append(num); bYBE h n
buff.append(",results:").append qT~a`ou:
],s{%a5wC
(results); $8WWN} OC
buff.append("}"); " 6ScVa5)
return buff.toString(); .,F`*JVFq
} vEw8<<cgg
2#oU2si
} _F},Wp:Oh
Lu
CiO
X^Fc^U8