Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !<~.>5UQ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `{>/'o
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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 3]JJCaf
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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 juF=ZW%i
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分页支持类: jG{?>^
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java代码: Lm`-q(!7w
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package com.javaeye.common.util; nF]R"
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import java.util.List; VUUnB<j
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publicclass PaginationSupport { q#c+%,Z=C
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publicfinalstaticint PAGESIZE = 30; ,ps?@lD
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privateint pageSize = PAGESIZE; ai?J
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privateList items; oVHe<zE.
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privateint totalCount; ~:Z|\a58j
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privateint[] indexes = newint[0]; )ADI[+KW
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privateint startIndex = 0; W>+`e]z
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public PaginationSupport(List items, int x!s=Nola
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totalCount){ iVeH\a
setPageSize(PAGESIZE); P~!,"rY
setTotalCount(totalCount); MLTS<pW/
setItems(items); p>?(uGV
setStartIndex(0); GQYn |vm
} ]5a3e+
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public PaginationSupport(List items, int `.~S/$a.&
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totalCount, int startIndex){ N&
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setPageSize(PAGESIZE); d\3 %5Y
setTotalCount(totalCount); d]|K%<+(
setItems(items); _>`9]6\&
setStartIndex(startIndex); @,,G]4zZ!
} 9@"pR;X@
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public PaginationSupport(List items, int q#8\BOTP |
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totalCount, int pageSize, int startIndex){ (m!kg
setPageSize(pageSize); I*>q7Hsu
setTotalCount(totalCount); q~aj"GD
setItems(items); }L|B@fW
setStartIndex(startIndex); ; (}~m&p
} lAo ~w
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publicList getItems(){ Q
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return items; ^.@%n1I"5y
} ~e,l2
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publicvoid setItems(List items){ vdUKIP
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this.items = items; `IBNBJy
} 5cA:;{z];g
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publicint getPageSize(){ k_u!E3{~
return pageSize; 7uw-1F5x7
} Z6Mjc/
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publicvoid setPageSize(int pageSize){ NM:$Q<n
this.pageSize = pageSize; j7w9H/XF}
} W58?t6!
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publicint getTotalCount(){ C]JK'K<7-
return totalCount; Zz:%KUl3
} FhBV.,bU,m
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publicvoid setTotalCount(int totalCount){ [8Z#HjhQ
if(totalCount > 0){ |"Zf0G
this.totalCount = totalCount; ^K J#dT
int count = totalCount / 9:xs)t- _
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pageSize; sb_/FE5e
if(totalCount % pageSize > 0) cg]Gt1SU
count++; Qp:m=f6@
indexes = newint[count]; ydY(*]
for(int i = 0; i < count; i++){ rrgOp5aV"
indexes = pageSize * fXnewPr=#
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} /L(}VJg-
}else{ 4|cRYZj5
this.totalCount = 0; g#6R(
} FaWc:GsfB
} znWB.H
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publicint[] getIndexes(){ PvW4%A@0
return indexes; +CSv@ />3
} )+,h}XqlX
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publicvoid setIndexes(int[] indexes){ O.y ?q
this.indexes = indexes; NB^Al/V@
} \pI {b9
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publicint getStartIndex(){ "|&3z/AUh
return startIndex; Hiwij,1
} oz]3
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publicvoid setStartIndex(int startIndex){ 6~{'\Z
if(totalCount <= 0) "G*$#
this.startIndex = 0; \AoqOC2u
elseif(startIndex >= totalCount) )J+OyR=
this.startIndex = indexes
}#&[[}@th
9qGba=}Ey
[indexes.length - 1]; #k d9}
elseif(startIndex < 0) :nl,Ac
this.startIndex = 0; sEfT#$ a^8
else{ 6pC1C.
this.startIndex = indexes Vz-q7*o$S
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[startIndex / pageSize]; PC255
} c,)]!{c
} s7:_!Nd@8
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publicint getNextIndex(){ "u$XEA
int nextIndex = getStartIndex() + /D|q-`*K
x}WP1YyT~
pageSize; ;[P>
if(nextIndex >= totalCount) >fT%CGLC0
return getStartIndex(); xbcmvJrG
else (5+g:mSfr
return nextIndex; :p)^+AF"5
} bJ6C7-w:wa
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publicint getPreviousIndex(){ g$Vr9MH
int previousIndex = getStartIndex() - ofz?L#:2
Q*'OY~
pageSize; (IjM
if(previousIndex < 0) km^ZF<. @
return0; SS_6VE*sI
else .ej+?QYwC
return previousIndex; p9\*n5{
} IW@phKz
{w"Cr0F,
} }$uwAevP{y
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抽象业务类 x\:KfYr4Y;
java代码: v,~fG>Y}
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/** e$Yvy>I'tS
* Created on 2005-7-12 fJk'5kv
*/ Sj/v:
package com.javaeye.common.business; F9las#\J
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import java.io.Serializable; #k>A,
import java.util.List; L>7@!/9L
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import org.hibernate.Criteria; \x4:i\Fx@
import org.hibernate.HibernateException; D Vg$rm`
import org.hibernate.Session; }[@Q**j(
import org.hibernate.criterion.DetachedCriteria; W
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import org.hibernate.criterion.Projections; cud9oJ-=;
import nsV=
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org.springframework.orm.hibernate3.HibernateCallback; :.a184ax
import %WmTG }L)
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org.springframework.orm.hibernate3.support.HibernateDaoS vE#8&Zq
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upport; BjTgZ98J
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import com.javaeye.common.util.PaginationSupport; SG0PQ
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public abstract class AbstractManager extends /S~ =qodS
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HibernateDaoSupport { bd27])n(
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privateboolean cacheQueries = false; JqYa~6 C
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privateString queryCacheRegion; [^/a`Kda8
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publicvoid setCacheQueries(boolean 0u( 0*Xl
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cacheQueries){ {t|#>UCK
this.cacheQueries = cacheQueries; &^ s8V]^
} ,jw`9a
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publicvoid setQueryCacheRegion(String Zvfy%k
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queryCacheRegion){ )4:]gx#cr
this.queryCacheRegion = <1*\ ~CX
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queryCacheRegion; Q uw|KL
} Vwjic2lGI
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publicvoid save(finalObject entity){ BxQ,T@
getHibernateTemplate().save(entity); u.?jW vcv
} 3qH1\
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publicvoid persist(finalObject entity){ 7d|1T'
getHibernateTemplate().save(entity); )z4eRs F|
} utC^wA5U~
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publicvoid update(finalObject entity){ f:~$x
getHibernateTemplate().update(entity); cF9oo%3
} (mI590`f
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publicvoid delete(finalObject entity){ tc\ZYCFr
getHibernateTemplate().delete(entity); `cN8AcRHP
} vv^y
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publicObject load(finalClass entity, 5gC>j(
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finalSerializable id){ &0%B3
return getHibernateTemplate().load ORWi+H|
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(entity, id); =d:3]M^
} -O-?hsV)y
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publicObject get(finalClass entity, &uBfsa$
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finalSerializable id){ Iu >4+6
return getHibernateTemplate().get co^h2b
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(entity, id); QF*cdc<
} WQD:~*C:
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publicList findAll(finalClass entity){ fM*?i"j;Y
return getHibernateTemplate().find("from 8$ #z>
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" + entity.getName()); 5a)$:oO!
} 72*j6#zS
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publicList findByNamedQuery(finalString Q|S>C%4?
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namedQuery){ [cl+AV "
return getHibernateTemplate tXZMr
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().findByNamedQuery(namedQuery); @M'qi=s*
} Zkqq<
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publicList findByNamedQuery(finalString query, PDCb(5
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finalObject parameter){ KU+\fwYpnk
return getHibernateTemplate ]IeLKcn
Ck"db30.
().findByNamedQuery(query, parameter); 4*5 e0:O
} WXDo`_{R
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publicList findByNamedQuery(finalString query, KtH^k&z.f
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finalObject[] parameters){ k%kEW%I yG
return getHibernateTemplate pLV
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().findByNamedQuery(query, parameters); t imY0fx#
} a)Pr&9I
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publicList find(finalString query){ 7n+,!oJ
return getHibernateTemplate().find _9p79S<+
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(query); NuUiW*|`7
}
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publicList find(finalString query, finalObject 1\Pjz
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parameter){ i1m>|[@k
return getHibernateTemplate().find F[!%,-*
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(query, parameter); T{"Ur:p
} n~}[/ly
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public PaginationSupport findPageByCriteria W3\E;C-g0
2 >j0,2
(final DetachedCriteria detachedCriteria){ $ Y^0l
return findPageByCriteria p4UEhT
re}PpXRC
(detachedCriteria, PaginationSupport.PAGESIZE, 0); r)K5<[\r
} &/)B d%
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public PaginationSupport findPageByCriteria HIvSpO
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(final DetachedCriteria detachedCriteria, finalint 'gg<)Bd
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startIndex){ ^~7Mv^A
return findPageByCriteria z9g6%RbwX
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i
(detachedCriteria, PaginationSupport.PAGESIZE, B$x@I\(M
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startIndex); BT_XqO
} cL;%2TMk
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public PaginationSupport findPageByCriteria g7*Uuh#
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(final DetachedCriteria detachedCriteria, finalint ~1twGG_;
}HmkTk
pageSize, k`|E&+og
finalint startIndex){ '<uM\v^k
return(PaginationSupport) o|c6=77043
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getHibernateTemplate().execute(new HibernateCallback(){ M"/Jn[
publicObject doInHibernate jX(${j<
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(Session session)throws HibernateException { WWZ<[[ >
Criteria criteria = dJJq]^|
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detachedCriteria.getExecutableCriteria(session); ^,AE;ZT7
int totalCount = Q@>1z*'I
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((Integer) criteria.setProjection(Projections.rowCount Qzo -Yw`=
d^!k{Qx'
()).uniqueResult()).intValue(); I}0? d
criteria.setProjection !k*B-@F
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(null); _X;,,VEV!
List items = ZeU){CB
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criteria.setFirstResult(startIndex).setMaxResults ecoI-@CAI
8 sc2r
(pageSize).list(); YGLq~A
PaginationSupport ps = v~T)g"_|
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new PaginationSupport(items, totalCount, pageSize, D6&P9e_5
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startIndex); E QU@';~8
return ps; fDplYn#
} Qj_)^3`e
}, true); x>TIx[x
} }5(_gYr
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public List findAllByCriteria(final V6HZvuXV!
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DetachedCriteria detachedCriteria){ <PuY"-`/Oc
return(List) getHibernateTemplate sCzpNJ"8
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().execute(new HibernateCallback(){ F+Qnf'at1
publicObject doInHibernate 1Td`S1'#yg
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(Session session)throws HibernateException { iQ8{N:58DN
Criteria criteria = -Pt E+R[A
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detachedCriteria.getExecutableCriteria(session); h@=@
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return criteria.list(); 9"+MZ$
} Xy 4k;+
}, true); )V[j~uOU)]
} )$9wKk\F
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public int getCountByCriteria(final 0=6mb]VUi=
,\P|%yv
DetachedCriteria detachedCriteria){ "U4c'iW
Integer count = (Integer) eaDZ^Z
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getHibernateTemplate().execute(new HibernateCallback(){ 'l~7u({u
publicObject doInHibernate Ot`%5<E^
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(Session session)throws HibernateException { &&P9T/Zks
Criteria criteria = uj.$GAtO)
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detachedCriteria.getExecutableCriteria(session); 3!gz^[!?EN
return #t(/wa4
{ >[ ]iX
criteria.setProjection(Projections.rowCount VV/T)qEe7>
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()).uniqueResult(); H%U
} t`|Rn9-
}, true); H+Bon=$cE!
return count.intValue();
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} #TR!x,Hc
} *K$a;2WjzG
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用户在web层构造查询条件detachedCriteria,和可选的 F) Q[ cai
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 U+B"$yBR
*k,3@_5
PaginationSupport的实例ps。 yLfyLyO L
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ps.getItems()得到已分页好的结果集 9D=X3{be#
ps.getIndexes()得到分页索引的数组 /ZabY
ps.getTotalCount()得到总结果数 |g^YD;9s.
ps.getStartIndex()当前分页索引 *kK +Nvt8s
ps.getNextIndex()下一页索引 l9eTghLi
ps.getPreviousIndex()上一页索引 .U|'KCM9m
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 T$2A2gb`
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 x
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一下代码重构了。 %u&Vt"6m=
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我把原本我的做法也提供出来供大家讨论吧: h'h8Mm
H#hpaP;
首先,为了实现分页查询,我封装了一个Page类: ]] 0 M
java代码: 86-Rm
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/*Created on 2005-4-14*/ DeF`#a0E
package org.flyware.util.page; I
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/** ;ZI8vFb
* @author Joa ,#,K_oz
* ?87\_wL/j
*/ Vfy@?x=
&
publicclass Page { J0R{|]W8
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/** imply if the page has previous page */ >@bU8}rT
privateboolean hasPrePage; +<xQF
@"fv[=Xb
/** imply if the page has next page */ ]6`K
privateboolean hasNextPage; JC~sz^>p\
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/** the number of every page */ CStNCBZ|\
privateint everyPage; ]O:8o<0
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/** the total page number */ "OI$PLK
privateint totalPage; cW0\f5[/
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/** the number of current page */ CT|0KB&
privateint currentPage; UQh.o
8h|} Q _
/** the begin index of the records by the current sRcd{)|Cq
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query */ [&&#~gz
privateint beginIndex; 2@Nd02v|
~$4(|Fq/
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/** The default constructor */ UIf#Gy|l
public Page(){ (NR( )2
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} (_}q>3
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/** construct the page by everyPage oO?+2pTQV
* @param everyPage Q!IqvmO
* */ lW#2 ox
public Page(int everyPage){ Y9#dAI[Gce
this.everyPage = everyPage; 1:T"jsWw
} MNe/H\
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/** The whole constructor */ O_2o/
public Page(boolean hasPrePage, boolean hasNextPage, m2(}$z3e
wY\,b*x
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int everyPage, int totalPage, lbovwj
int currentPage, int beginIndex){ $0$sDN6)x
this.hasPrePage = hasPrePage; :/][ n9J^
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; xh#_K@ 8
this.totalPage = totalPage; LHZsmUM(dg
this.currentPage = currentPage; sxF2ku4A
this.beginIndex = beginIndex; 9$X" D
} 0$Mxu7 /
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/** T^7}Qs9
* @return /[>_Ry,
* Returns the beginIndex. NkGtZ.!pk
*/ >+i+_^]
publicint getBeginIndex(){ Er@xrhH
return beginIndex; Ei]SksV>*
} b g0ix"
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/** O z(=%oS
* @param beginIndex m !<FlEkN
* The beginIndex to set. tuwlsBV
*/ `:r-&QdU o
publicvoid setBeginIndex(int beginIndex){ &DYC3*)Jih
this.beginIndex = beginIndex; '*`n"cC:
} .,S`VNU
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/** 16I[z+RG
* @return 9&^5!R8
* Returns the currentPage. yCkc3s|DA;
*/ -9+$z|K
publicint getCurrentPage(){ a $'U?%
return currentPage; a[zVC)N0
} 525^/d6v
N|)e {|k
/** s-SFu
* @param currentPage Z)(#D($-
* The currentPage to set. jYAm}_?No
*/
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publicvoid setCurrentPage(int currentPage){ fYZd:3VdC
this.currentPage = currentPage; !JDuVqW
} 3''Kg<k,I
j8?! J^TC
/** #!TlalV
* @return
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* Returns the everyPage. oIj/V|ByK
*/ >^#Liwm
publicint getEveryPage(){ :si&A;k
return everyPage; ^o q|^O
} L?8OWLjRy
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/** G^L9[c= ,
* @param everyPage w0sy@OF
* The everyPage to set. C.uv0
*/ _M;{}!Gc&A
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; A
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} r_bG+iw7p
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/** bqF?!t<B
* @return 4C:dkaDq]
* Returns the hasNextPage. {4[dHfIy
*/ ^-~=U^2tC
publicboolean getHasNextPage(){ 2|RxowXZ"
return hasNextPage; i[.7 8K-s
} SZtSUt(ss
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/** 5mudww`
* @param hasNextPage zh?B-"O=5
* The hasNextPage to set. -g9CW[
*/ qOyS8tA.H
publicvoid setHasNextPage(boolean hasNextPage){ ++8 Xi1
this.hasNextPage = hasNextPage; r}|)oG,=
} ?6N\AM'
7uv"# mq
/** Pq-@waH3
* @return oz3!%'
* Returns the hasPrePage. l%
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*/ 7:$dl#
publicboolean getHasPrePage(){ 4RQ38%> >j
return hasPrePage; trLxg H_Y
} }VH2G94Ll
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/** R[vX+d!7
* @param hasPrePage v=uQ8_0~N
* The hasPrePage to set. X^m@*,[s
*/ V0#E7u`4
publicvoid setHasPrePage(boolean hasPrePage){ 'rfsrZ?
this.hasPrePage = hasPrePage; BTA2['
} .OW5R*
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/** Mj19;nc0I
* @return Returns the totalPage.
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* Xpkj44cd@
*/ >A6PH*x
publicint getTotalPage(){ %2G3+T8*x
return totalPage; Ia^/^>
} )J[Ady^5
.'-t>(}v
/** [a^<2V!vMn
* @param totalPage [c=![*}/
* The totalPage to set. b4ke'gx
*/ P=9sP:[f6
publicvoid setTotalPage(int totalPage){ F*:H&,
this.totalPage = totalPage; DAMw(
} geqx":gpx9
`I|Y7GoUO
} cIuCuh0I`
pFo,@M
dftX$TS
`\BBdQ#bH
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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 Fk`6
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个PageUtil,负责对Page对象进行构造: c Ct5m
java代码: hGUQdTNP
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/*Created on 2005-4-14*/ ]HG>Og
package org.flyware.util.page; MAc/ T.[
N71^ I"@HH
import org.apache.commons.logging.Log; ZU9Rvtb KB
import org.apache.commons.logging.LogFactory; 8Tc:TaL
f+c{<fX
/** L#_QrR6Sny
* @author Joa W;,RU8\f
* w;Pe_m7\EO
*/ `-rtU
publicclass PageUtil { H[r6 4~Sth
$T2zs$
privatestaticfinal Log logger = LogFactory.getLog <2+FE/3L
%NL7XU[~
(PageUtil.class); z`8>$9
V F"c}
/** #Pq6q.UB
* Use the origin page to create a new page t 9.iWIr
* @param page 2l8z/o 7v
* @param totalRecords i}5+\t[Q
* @return 57U;\L;ZmZ
*/ C[JPohm
publicstatic Page createPage(Page page, int yv5c0G.D
$)(Zt^
totalRecords){ @Z~0!VY
return createPage(page.getEveryPage(), Ti5"a<R4m6
3SOrM
page.getCurrentPage(), totalRecords); x C>>K6Nb
} )q%DRLD'G
@hOY&
/** LFQPysC
* the basic page utils not including exception DJ NM=v
6rAenK-%
handler Y3luU&'
* @param everyPage w6k^|."
* @param currentPage mw=keY9]
* @param totalRecords -.vNb!=
* @return page IBv9xP]BZ
*/ Sj4 @pMh4
publicstatic Page createPage(int everyPage, int [#2z=Xg
\88IFE
currentPage, int totalRecords){ @,q<][q
everyPage = getEveryPage(everyPage); 9kU|?JE
currentPage = getCurrentPage(currentPage); js=w!q0)9
int beginIndex = getBeginIndex(everyPage, ns8I_H
\,b_8^
currentPage); (K>4^E8
int totalPage = getTotalPage(everyPage, d!q)FRzi
wQ9fPOm
totalRecords); mY]R~:
boolean hasNextPage = hasNextPage(currentPage, 9t0NO-a
n11eJEtm
totalPage); 9uY$@7qH
boolean hasPrePage = hasPrePage(currentPage); > bSQ}kXe
X57\sggK
returnnew Page(hasPrePage, hasNextPage, EF'U`\gX
everyPage, totalPage, ]P(_
d'}
currentPage, sMb+4{W&6
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beginIndex); xV5eKV
} @1 )][r-7
:U#4H;kk~j
privatestaticint getEveryPage(int everyPage){ 0o&7l%Y/
return everyPage == 0 ? 10 : everyPage; j&=!F3[
} N7qSbiRf<
lV<j?I~?Q
privatestaticint getCurrentPage(int currentPage){ R&s\h"=*
return currentPage == 0 ? 1 : currentPage; ob>2SU[Y
} &1Idv}@!
I =yy
I
privatestaticint getBeginIndex(int everyPage, int q \\52:\
H9T'{R*FC
currentPage){ vC!}%sxVw_
return(currentPage - 1) * everyPage; 'd=B{7k@
} rc]`PV
.^*
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privatestaticint getTotalPage(int everyPage, int OLxiY r
Z&0*\.6S~
totalRecords){ w#`E;fN'
int totalPage = 0;
{3=]cLtt
IH'&W
if(totalRecords % everyPage == 0) FFqqAT5
totalPage = totalRecords / everyPage; \*$''`b)j
else #a"gW,/K
totalPage = totalRecords / everyPage + 1 ; IG~d7rh"
XQL]I$?
return totalPage; Q68q76
} *b]$lj
N;]"_"
privatestaticboolean hasPrePage(int currentPage){ `+Ojh>"*z*
return currentPage == 1 ? false : true; 2q.J1:lW
} &8uq5uKg
*J] }bX
privatestaticboolean hasNextPage(int currentPage, '\.fG\xD
(
RCQbI
int totalPage){ 72 >/@
return currentPage == totalPage || totalPage ==
^iaG>rvA
VKp4FiI6
0 ? false : true; }
^67HtNQ
} b7h0V4w
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OfGMeN6
} I='S).
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Fm3B8Int
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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。 w{;esU
48 `k"Uy
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 jN43vHm\Y9
RZV6\j
做法如下: 1FiFP5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象
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Cj x(Z]
的信息,和一个结果集List: "eiZZSz
java代码: WS?"OTH.^\
4 <`'?
WM_wkvYl
/*Created on 2005-6-13*/ Spossp`|
package com.adt.bo; jKI0d+U
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import java.util.List; S~mpXH@
Z&!5'_9{V
import org.flyware.util.page.Page; IP E2t
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/** QFm~wv8:
* @author Joa CG(G){u&
*/ &v\
publicclass Result { *uq;O*s
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private Page page; 2O^7zW
,s*-2Sz
private List content; YVMwb@|
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/** CE19V:zp
* The default constructor spE(s%dgL
*/ BuE=(v2}
public Result(){ Tq7cZe"6
super(); u"*@k^}(
} n:-:LSa+3
yrnIQu*Uu
/** %,G&By&,
* The constructor using fields $s*\yam?|
* qd=&*?
* @param page #&A)%Qbg
* @param content %B&y^mZv*\
*/ U=4tJb
public Result(Page page, List content){ ahno$[
this.page = page; yaiw|j`A
this.content = content; j`GL#J[wqQ
} &"(xd@V)]A
u!FX 0Ip
/** 2aef[TY
* @return Returns the content. Z9MT,
"
*/ f,ajo
publicList getContent(){ l
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return content; ^Gc#D:zU
} a&3pPfC
dVh* a
/** h7iI=[_V
* @return Returns the page. %.
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*/ Gm0&y
public Page getPage(){ '+6SkZ
return page; p_x@FA(
} nwOT%@nw
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/** \zA G#{
* @param content |#p`mc%f~\
* The content to set. w^e5" og]
*/ >}tm8|IHoo
public void setContent(List content){ &&/2oP+z
this.content = content; @j/UDM
} "Zo<$p3]
h/7m.p]
/** ^h}xFiAV#
* @param page 1Y2]jz4
* The page to set. \G+ hi9T(
*/
}pOem}
publicvoid setPage(Page page){ 1'O++j_%y
this.page = page; T)ZO+}
} 21b
} sYQ=nL
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0}a="`p#<
>h?!6L- d
S${n:e0\
2. 编写业务逻辑接口,并实现它(UserManager, IkzY
D<-MbK^S
UserManagerImpl) j06q3N"
java代码: R!mFMw"
Y7TW_[_u
3ZZ"mlk*
/*Created on 2005-7-15*/ @2>A\0U
package com.adt.service; k
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Sn(e@|!G
import net.sf.hibernate.HibernateException; ;}iV`)S
>5rb4
import org.flyware.util.page.Page; oCw>b]S
I{e[Y_
import com.adt.bo.Result; =Oo=&vA.oc
6Qo
YX] .
/** Q{s9{
* @author Joa fwe4f
*/ >l<`)4*H
publicinterface UserManager { op\'T;xIu
3#O Rfr(
public Result listUser(Page page)throws UcZ20inj0
T1\LS*~!
HibernateException; !p&[:+qN
(!^i6z0Sp
} E}7@?o7u}
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n};:*N!
v
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java代码: TuF;>{~}
,".1![b
|ia#Elavo
/*Created on 2005-7-15*/ nY]5pOF:
package com.adt.service.impl; `7v"(
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import java.util.List; )Z.v fc
3sh}(
import net.sf.hibernate.HibernateException; 4^3}+cJ7j
:5YL!D/&
import org.flyware.util.page.Page; DZ-2Z@{PX
import org.flyware.util.page.PageUtil; C;mcb$@
Pv- i.
import com.adt.bo.Result; t)!(s,;T
import com.adt.dao.UserDAO; ,;&j*qFi
import com.adt.exception.ObjectNotFoundException; %T~3xQ
import com.adt.service.UserManager; MBeubS
[&Yrnkgr
/** IE^xk@
* @author Joa 'AU:[eyUV
*/ |`N|S
publicclass UserManagerImpl implements UserManager { "s$$M\)T
thT2U8%T
private UserDAO userDAO; 8h,>f#)0c
8-s7^*!
/** ZGa;'
* @param userDAO The userDAO to set. &xAwk-{W
*/ T[M:%vjYF
publicvoid setUserDAO(UserDAO userDAO){ VLdQXNg9W"
this.userDAO = userDAO; y.iA]Ikz
} n<GTc{>Z
Gx&o3^ t
/* (non-Javadoc) QfdATK P
* @see com.adt.service.UserManager#listUser ^x BQ#p
(_9 u<
(org.flyware.util.page.Page)
W 'w{}|
*/ ^k*h
public Result listUser(Page page)throws \LN!k-c
*n"{] tj^>
HibernateException, ObjectNotFoundException { zwLJ|>
int totalRecords = userDAO.getUserCount(); W@bZ~Q9
if(totalRecords == 0) ?RP&XrD
throw new ObjectNotFoundException iE6?Px9]
uZ1b_e0SGu
("userNotExist"); |c<h&p
page = PageUtil.createPage(page, totalRecords); bR\Oyd~e
List users = userDAO.getUserByPage(page); j
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returnnew Result(page, users); rEoMj)~\4&
} i9RAbt Q}
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} 3Fu5,H EJ
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{^z>uRZ3
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |E}-j;(
prk@uYCa =
询,接下来编写UserDAO的代码: Wx:He8N] H
3. UserDAO 和 UserDAOImpl: d-rqZn}
java代码: M ^89]woC
e|-%-juI
?@>PKUv{
/*Created on 2005-7-15*/ b] 5i`
package com.adt.dao; VUneCt%
'vP"&lrn
import java.util.List; _9pcHhJux
>z"\l
import org.flyware.util.page.Page; I(5sKU3<
B7 #O>a
import net.sf.hibernate.HibernateException; +jPJv[W
WA?We7m$
/** T4JG5
* @author Joa G`oY(2U
*/ BzXTHFMSy
publicinterface UserDAO extends BaseDAO { 4#Bzq3,|
X$Y\/|!z
publicList getUserByName(String name)throws kgv29j?k;
_?I6[Mz
HibernateException; )8JfBzR
RSTA!?K/.
publicint getUserCount()throws HibernateException; |uIgZ|7[
,SF>$
.
publicList getUserByPage(Page page)throws )Y](Mj!D
d5YL=o
HibernateException; VE $Kdo^
r,r"?}Z
} yADX^r(
N hY`_?)
GzN /0:b
a
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hU~up a<dD
java代码: ^&z3zFTp
N0V`xrS
g9.y`o}c
/*Created on 2005-7-15*/ W[G5+*i
package com.adt.dao.impl; e#<A\?
W}iDT?Qi
import java.util.List; ul&}'jBr
cD5N'3
import org.flyware.util.page.Page; ev[!:*6P
;uhpo
import net.sf.hibernate.HibernateException; `gSJEq
import net.sf.hibernate.Query; 2)\gIMt%
u$Wv*;TT%
import com.adt.dao.UserDAO; Njmb{L]Cps
:5-t$^R
/** ;39~G T
* @author Joa +UX~TT:
*/ Swxur+hfH
public class UserDAOImpl extends BaseDAOHibernateImpl 9}|t`V"
1]wo
implements UserDAO { 3n)\D<f]#
wlEmy.)H
/* (non-Javadoc) 2~y<l
* @see com.adt.dao.UserDAO#getUserByName 5M?
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= tY%k!R
(java.lang.String) L$3{L"/
*/ 7csMk5NU'<
publicList getUserByName(String name)throws er0y~
9&"wfN N
HibernateException { =KW~k7TaN
String querySentence = "FROM user in class A5IW[Gu!
w\}Q.$@
com.adt.po.User WHERE user.name=:name"; ,c&%/"i:w
Query query = getSession().createQuery O|mWQp^?q
[+wLy3_
(querySentence); ] ]lN[J
query.setParameter("name", name); Ro.br:'Bw
return query.list(); U}<' [o
V
} 5,#aN}v#?
9zNMv-
/* (non-Javadoc) APv&
^\oUH
* @see com.adt.dao.UserDAO#getUserCount() Rebo.6rG
*/ G\B:iyKl
publicint getUserCount()throws HibernateException { 1#lH5|XQ
int count = 0; "3$P<Q\;l;
String querySentence = "SELECT count(*) FROM q!as~{!
n%d7`?tm4
user in class com.adt.po.User"; +EvY-mwfQ
Query query = getSession().createQuery -1%AM40j
m+EtB6r
(querySentence); Kwo0%2Onkd
count = ((Integer)query.iterate().next &9khIJIn
)5ev4Qf
()).intValue();
<y<
return count; ja%IGaH;s
} 2Xqa?ay0>
3RP\w~?
/* (non-Javadoc) D"<>!]@(a
* @see com.adt.dao.UserDAO#getUserByPage @0D
s(r1q$5
(org.flyware.util.page.Page) n*m"yp
*/ i{}Q5iy
publicList getUserByPage(Page page)throws 2SXy)m
!
Gxw>.O){
HibernateException { 4p&YhV7j)o
String querySentence = "FROM user in class t]XF*fZH
|HQFqa<
com.adt.po.User"; nyx(0
Query query = getSession().createQuery blmY=/]
VX'G\Zz@h|
(querySentence); yUX<W'-Hev
query.setFirstResult(page.getBeginIndex()) >8EmfjUoc
.setMaxResults(page.getEveryPage()); ;edt["Eu
return query.list(); 8.tp#x,A
} L[. )!c8k
zC WN,K`
} _YA;Nd#%k
Bi`m +ob
v4W<_
7L_
<xwaFZ
+|.6xC7U
至此,一个完整的分页程序完成。前台的只需要调用 a9p6[qOcd
l*|m(7s
userManager.listUser(page)即可得到一个Page对象和结果集对象 POb2U1Sj
8C5*: x9l
的综合体,而传入的参数page对象则可以由前台传入,如果用 zxy/V^mu
hEfFMi=a`
webwork,甚至可以直接在配置文件中指定。 Z#flu Q%V
ngl8) B
下面给出一个webwork调用示例: ?dQ#%06mn
java代码: )'e9(4[V1
Vee;&
wiM-TFT~
/*Created on 2005-6-17*/ 7DB!s@"
package com.adt.action.user; Yzih-$g
VR vX^w0
import java.util.List; vve[.Lud'
F=V_ACU
import org.apache.commons.logging.Log; JA
"
import org.apache.commons.logging.LogFactory; l/6(V:
import org.flyware.util.page.Page; M*<Bp
W-ol*S
import com.adt.bo.Result; F5YHc$3^
import com.adt.service.UserService; =f=,YcRn+
import com.opensymphony.xwork.Action; D|"^
:Gi
H 2UR
/** k^Uk=)9
* @author Joa ~.<}/GP] _
*/ p&cJo<]=LE
publicclass ListUser implementsAction{ 9I*i/fa
!kWx'tJ$
privatestaticfinal Log logger = LogFactory.getLog cQ`+ A|q
0r ilg
(ListUser.class); 8@BN6
6a*OQ{8
private UserService userService; fXB64MNo
=d1i<iw?-
private Page page;
4d )Q
C:P.+AU"`
privateList users; )Ga 3Ji}'
X{;3gN
/* (0QYX[(r~o
* (non-Javadoc) B{-+1f4
* }OLBEhGs
* @see com.opensymphony.xwork.Action#execute() XFcIBWS
*/
?ubIh.d
publicString execute()throwsException{ Jkub|w#QH
Result result = userService.listUser(page); ?KXgG'!!
page = result.getPage(); & <Jvaf_=
users = result.getContent(); "jAEZ
return SUCCESS; .>|]Lo(=l
} Y)9]I6n7
QTuj v<|
/** uJ>_
2
* @return Returns the page. = ms
o1
*/
-TKQfd
public Page getPage(){ MDh^ic5
return page; 6)Dp2
} '/K-i.8F
Tz 2<# pLR
/** jBnvu@K "
* @return Returns the users. t 4tXLI;'
*/ 8CN0Q&|
publicList getUsers(){ 7EukrE<b'
return users; 4@ =l'Fw
} mp+lN:
a>/jW-?
/** 2=ZZR8v
* @param page T0Zv.
* The page to set. ]WP[hF
*/ DeL7sU
publicvoid setPage(Page page){ nLv"ON~
this.page = page; yct^AN|%
} /Jw65 e
<-m?l6
/** uZ7~E._
* @param users 0G"I}Jp{
* The users to set. ]aVFWzey
*/ mtu`m6Xix
publicvoid setUsers(List users){ a]u1_ $)
this.users = users; /?Fa<{
} b|z_1j6U
J#tY$PE
/** ILq"/S.
* @param userService +x"cWOg
* The userService to set. YJEL'k<l
*/ kqie|_y
publicvoid setUserService(UserService userService){ I%fz^:[#<
this.userService = userService; y:N>t+'5
} ^9PB+mz
} *1fZcw'C.
Ib665H7w
@I$;
tZn=[X~Vw@
yvz2eAXa
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, FtL{f=
}I;5yk,o
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ><Z`)}f
;p}X]e l}
么只需要: 0/Wo":R:
java代码: LVX01ox$
p .^#mN
7ZVW7%,zF
<?xml version="1.0"?> T2V#
fYCc
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #`9D,+2iB%
xX]92Q
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;'x\L<b/)
EO[UezuU
1.0.dtd"> MGzuQrl{H
(o5+9'y"9
<xwork> h#iFp9N
$5;RQNhXh
<package name="user" extends="webwork- 0Zv<]xO
NFQR
interceptors"> "Lp"o
L?c7M}vV
<!-- The default interceptor stack name ve|`I=?2
H _%yh,L
--> l*Iy:j(B
<default-interceptor-ref M!ra3Y
ix=H=U]Q{
name="myDefaultWebStack"/> (YJ]}J^
ORo +=2
<action name="listUser" ADa'(#+6
;f8$vW];
class="com.adt.action.user.ListUser"> Rr'^l]
<param /:j9#kj
8v)PDO~D}A
name="page.everyPage">10</param> =5-|H;da
<result -bHfo%"^TT
%)K)h&m