Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N2duhI6
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &);P|v`8
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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 hwJ>IQ1
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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 1# z@D(
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分页支持类: ZILJXX4
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java代码: y1Z>{SDiq
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package com.javaeye.common.util; ,$>l[G;Bm
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import java.util.List; '@Rk#=85Z
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publicclass PaginationSupport { 3,6f}:CG
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publicfinalstaticint PAGESIZE = 30; ~?HK,`0h>
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privateint pageSize = PAGESIZE; gD4vV'|
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privateList items; 3Ke6lV)uq
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privateint totalCount; 7*KUM6z
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privateint[] indexes = newint[0]; 6kdbbGO-
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privateint startIndex = 0; "NGfT:HV
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public PaginationSupport(List items, int L/C~l3
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totalCount){ M\{\WyeX
setPageSize(PAGESIZE); s hH2/.>
setTotalCount(totalCount); js5VgP`
setItems(items); tkr&Fs"t+
setStartIndex(0); @*Ry`)T
} y#iz$lX R
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public PaginationSupport(List items, int w]{c*4o
x;z=[eE
totalCount, int startIndex){ p^<(.+P4
setPageSize(PAGESIZE); -mG`* 0
setTotalCount(totalCount); f'@ L|&w
setItems(items); Hxgc9Fis
setStartIndex(startIndex); /r"<:+
} $Vq5U9-
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public PaginationSupport(List items, int prz COw
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totalCount, int pageSize, int startIndex){ PRaVe,5a
setPageSize(pageSize); n{sk
setTotalCount(totalCount); "YgpgW
setItems(items); B#jnM~fJz
setStartIndex(startIndex); nv@z;#&
} |`#fX(=
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publicList getItems(){ ; /K6U
return items; #YE?&5t
} &TQ~!ZMOR"
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publicvoid setItems(List items){ Z6i~Dy3
this.items = items; PD.$a-t
} S,AxrQc
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publicint getPageSize(){ 5 k3m"*
return pageSize; fP|[4 ku
} In96H`
;6[6~L%K}
publicvoid setPageSize(int pageSize){ 8lYA6A
this.pageSize = pageSize; wPjq
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} ZxwrlaA
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publicint getTotalCount(){ A%W]XEa<
return totalCount; U,EoCAm>
} K%\r[NF
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publicvoid setTotalCount(int totalCount){ a- rR`
if(totalCount > 0){ @`4T6eL5
this.totalCount = totalCount; Mp|Jt
int count = totalCount / cE
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<Q9l'u]3$c
pageSize; _90D4kGU
if(totalCount % pageSize > 0) $5JeN{B
count++; |du%c`wl
indexes = newint[count]; 018SFle
for(int i = 0; i < count; i++){ )
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indexes = pageSize * )/;+aDk
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i; fOHbgnL>
} &`l\Q\_[@
}else{ l1DJ<I2
this.totalCount = 0; g&xj(SMj-$
} @9HRGxJ=}
} nwKp8mfP
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publicint[] getIndexes(){ h2Nt@
return indexes; )4=86>XJT
} OA&'T*)-A6
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publicvoid setIndexes(int[] indexes){ H@1'El\9
this.indexes = indexes; $kTm"I
} &<98nT
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publicint getStartIndex(){ SZ9Oz-?
return startIndex; :$b` n
} //2O#Fg{/
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publicvoid setStartIndex(int startIndex){ m1pA]}Y/5o
if(totalCount <= 0) @-dGZ5
this.startIndex = 0; {wz)^A
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elseif(startIndex >= totalCount) ,^?g\&f(
this.startIndex = indexes qhxMO[f
hi!A9T3%}M
[indexes.length - 1]; mcd{:/^?
elseif(startIndex < 0) wG[nwt0L
this.startIndex = 0; 8j#S+=l>
else{ 1DB{"8ov
this.startIndex = indexes V
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[startIndex / pageSize]; Q`9c/vPU
} UXBWCo;-
} '/u|32
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publicint getNextIndex(){ sWr;%<K
int nextIndex = getStartIndex() + B<SE|~\2
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pageSize; #("M4}~
if(nextIndex >= totalCount) tVAo o-%
return getStartIndex(); &<e18L7a
else >SDQ@63E?
return nextIndex; !YAX.e
} D0jV}oz
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publicint getPreviousIndex(){ 7(+4^
int previousIndex = getStartIndex() - 9?,i+\)qK@
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pageSize; x;7l>uR
if(previousIndex < 0) Qf( A
return0; T5u71C_wmt
else jlj ge=#c2
return previousIndex; t<` As6}
} p$\>3\
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}
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抽象业务类 [L+*pW+$\.
java代码: k4V3.i!E
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/** -r sbSt ?_
* Created on 2005-7-12 (Y)2[j
*/ &K0b3AWc
package com.javaeye.common.business; `CVkjLiy
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import java.io.Serializable; Kz42AC
import java.util.List; z='%NZY
1GK.:s6.f
import org.hibernate.Criteria; /X_L>or
import org.hibernate.HibernateException; #Q!Xz2z2
import org.hibernate.Session; j2Dw7"f3
import org.hibernate.criterion.DetachedCriteria; **h4M2'C
import org.hibernate.criterion.Projections; AZQQge
import d MR?pbD
v`,!wS
org.springframework.orm.hibernate3.HibernateCallback; 5=C?,1F$A
import !Sn|!:N4
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org.springframework.orm.hibernate3.support.HibernateDaoS =Mx"+/Yo*
5c]:/9&
upport; 1@p,
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import com.javaeye.common.util.PaginationSupport; ]Kq<U%x$
9iG&9tB@
public abstract class AbstractManager extends X~jdOaq{F:
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HibernateDaoSupport { G"?7 Z&+
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privateboolean cacheQueries = false; U/enq,-F^
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privateString queryCacheRegion; vIJ5iLF
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publicvoid setCacheQueries(boolean [<53_2]~
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cacheQueries){ OCrTzz8
this.cacheQueries = cacheQueries; <ZSXOh,'
} `w
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publicvoid setQueryCacheRegion(String M]PZwW8
@~$d4K
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queryCacheRegion){ ^nPy(Q0
this.queryCacheRegion = O(W"QY
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queryCacheRegion; mzK0$y#*o
} D-/6RVq0m
!-}Q{<2@W
publicvoid save(finalObject entity){ I9Ohz!RQ
getHibernateTemplate().save(entity); t?>}0\1
} -E|"?
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publicvoid persist(finalObject entity){ A:(|"<lA
getHibernateTemplate().save(entity); Vbv^@Kp
} q?7''xk7
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publicvoid update(finalObject entity){ 6#U~>r/
getHibernateTemplate().update(entity); ]!AS%D`
} FXBmatBck
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publicvoid delete(finalObject entity){ I4N7wnBp
getHibernateTemplate().delete(entity); zU!{_Ao9
} J`5+Zngr
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publicObject load(finalClass entity, s8,YQ5-
o)5zvnu7
finalSerializable id){ :o^ioX.J
return getHibernateTemplate().load X&zGgP/
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(entity, id); :<P4=P P
} GPHb-
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publicObject get(finalClass entity, i[KXkjr
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finalSerializable id){ z|3v~,
return getHibernateTemplate().get @]n8*n
S} UYkns*
(entity, id); 1!^BcrG.
} h/tCve3Z
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publicList findAll(finalClass entity){ F\N0<o
return getHibernateTemplate().find("from 7#C$}1XJ1
2B$dT=G
" + entity.getName()); IQ<G.
} Sk53Lc
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publicList findByNamedQuery(finalString TQO|C?
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namedQuery){ Mrk3r/
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return getHibernateTemplate [l^XqD D4
{ 8 K
().findByNamedQuery(namedQuery); 4|_xz;i
} :? B4q#]N
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publicList findByNamedQuery(finalString query, CCG5:xS
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finalObject parameter){ 0\!Bh^++1
return getHibernateTemplate i{EQjZ
]@9W19=P!P
().findByNamedQuery(query, parameter); A]m*~Vj]
} P\Qvj7_
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publicList findByNamedQuery(finalString query, "&SE!3*m`I
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finalObject[] parameters){ C2R"96M7q
return getHibernateTemplate >e!J(4.-
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().findByNamedQuery(query, parameters); Kv*
1=HES
} #6c,_!
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publicList find(finalString query){ fwt+$`n
return getHibernateTemplate().find )*}\fmOv{
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(query); 9)+!*(D
} ^
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publicList find(finalString query, finalObject 5)f 'wVe
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parameter){ x3Cn:F
return getHibernateTemplate().find UZt3Ua&J
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QP(
(query, parameter); WY|~E%k
} CX/[L)|Ru
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public PaginationSupport findPageByCriteria L$c 1<7LU
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(final DetachedCriteria detachedCriteria){ 8-+# !]
return findPageByCriteria fV4eGIR&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]u|FcwWc3
} I*U7YqDC9
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public PaginationSupport findPageByCriteria ?W ^`Fa)]o
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(final DetachedCriteria detachedCriteria, finalint ):G+*3yb
r^.9
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startIndex){ o]p$
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return findPageByCriteria o!h::j0,~
VB/75xK_
(detachedCriteria, PaginationSupport.PAGESIZE, =UO7!vr;[
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startIndex); hFoeVM[h
} }6LcimQyK
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public PaginationSupport findPageByCriteria ,hNs{-*
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(final DetachedCriteria detachedCriteria, finalint c)Q-yPMl)
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pageSize, =^M Q 4
finalint startIndex){ ?_{{iil
return(PaginationSupport) TQt[he$O
@&HLm^j2O
getHibernateTemplate().execute(new HibernateCallback(){ L7 FFa:#
publicObject doInHibernate SgQmR#5
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(Session session)throws HibernateException { ]p(es,[
Criteria criteria = CA|W4f}
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detachedCriteria.getExecutableCriteria(session); ?a+J4Zr3
int totalCount = [EPRBK`=
_Hq)@AI
((Integer) criteria.setProjection(Projections.rowCount M| }?5NS
7KC2%s#7
()).uniqueResult()).intValue(); CiU^U|~ 'L
criteria.setProjection qu1! KS
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(null); P<1&kUZL
List items = e#6H[t
NB3+kf ,
criteria.setFirstResult(startIndex).setMaxResults \K2S.j
C.=%8|Zy
(pageSize).list(); }rVLWt
PaginationSupport ps = C]ho7qC
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new PaginationSupport(items, totalCount, pageSize, s Fk{Tv@Yz
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startIndex); @B+8' b$9
return ps; y\6C9%.
} G?s;L NR
}, true); 2CtCG8o
} wMm+E "}W
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public List findAllByCriteria(final sAX4giaLD
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DetachedCriteria detachedCriteria){ |.~2C14[
return(List) getHibernateTemplate 2sBYy 8.r
o 8^!wGY
().execute(new HibernateCallback(){ 4.%/u@rAi
publicObject doInHibernate z2.OR,R}]
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(Session session)throws HibernateException { \ 511?ik
Criteria criteria = q 3,p=ijJ
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detachedCriteria.getExecutableCriteria(session); F%ukT6xp
return criteria.list(); slA~k;K:_
} !9zs>T&9a\
}, true); (ia+N/$u
} eZpi+BRS6
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public int getCountByCriteria(final 7m(9|Y:Q.
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DetachedCriteria detachedCriteria){ ->'q
Integer count = (Integer) '}Jq(ah(
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getHibernateTemplate().execute(new HibernateCallback(){ &C/,~pJ1S
publicObject doInHibernate dr=KoAIxy
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(Session session)throws HibernateException { DQ6pe)E|
Criteria criteria = lt l(SIi
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detachedCriteria.getExecutableCriteria(session); <~5$<L4
return "Bn]-o|r
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criteria.setProjection(Projections.rowCount [+dTd2uZ<\
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()).uniqueResult(); iaaD1<m
} FefS]G
}, true); {M0pq3SL*t
return count.intValue(); B&lF!
]
} }PzYt~Z`@
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用户在web层构造查询条件detachedCriteria,和可选的 ByXcs'
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 WB|SXto%4D
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PaginationSupport的实例ps。 ~F]If \b
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ps.getItems()得到已分页好的结果集 '"Dgov$q
ps.getIndexes()得到分页索引的数组 dLu3C-.(
ps.getTotalCount()得到总结果数 6EX8,4c\
ps.getStartIndex()当前分页索引 |)R{(AK-
ps.getNextIndex()下一页索引 GmLKg >%
ps.getPreviousIndex()上一页索引 ki_Py5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (A8X|Y
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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 V,Br|r$l(
w6l8RNRe
一下代码重构了。 jJCd2O]
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我把原本我的做法也提供出来供大家讨论吧: fqU*y 6]
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首先,为了实现分页查询,我封装了一个Page类: \XlT
java代码: }Pe0zx.Ge
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/*Created on 2005-4-14*/ 8MPXrc,9-
package org.flyware.util.page; as6YjE.Yy
fg1["{\
/** snyg
* @author Joa vSy#[9}
* [Y]\sF;J
*/ y"SVZ} ;|
publicclass Page { h"G#} C]
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/** imply if the page has previous page */ K%A:W
privateboolean hasPrePage; hK&/A+*
<$'OSN`!
/** imply if the page has next page */ GoNX\^A
privateboolean hasNextPage; ,0=:06l
@'EU\Y\l
/** the number of every page */ n +z5;'my
privateint everyPage; vrD]o1F
xTW$9>@\m
/** the total page number */ Y_49UtJIg
privateint totalPage; f?1?$Sp/W
X4U$#uI{
/** the number of current page */ E=Z.v
privateint currentPage; k%)QrRnB
SXA_P{j&a
/** the begin index of the records by the current EnGVp<6R
C-abc+/
query */ /=}w%-;/;
privateint beginIndex; |A#pG^
/8i3 I5*
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/** The default constructor */ #B3P3\
public Page(){ OFTyN^([@
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} cf#2Wg)
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/** construct the page by everyPage kqfO3{-;{:
* @param everyPage ~e5hfZv|w
* */ C$~2FTx
public Page(int everyPage){ 25RFi24>D
this.everyPage = everyPage; Y9)uy 8c
} YzqUOMAt"V
w NlC2is
/** The whole constructor */ ao]Dm#HiO
public Page(boolean hasPrePage, boolean hasNextPage, lr:rQw9
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int everyPage, int totalPage, r
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int currentPage, int beginIndex){ G'oMZb ({=
this.hasPrePage = hasPrePage; x roo_
this.hasNextPage = hasNextPage; `;yfSoY
this.everyPage = everyPage; 82.::J'e
this.totalPage = totalPage; J|-X?V;ZW
this.currentPage = currentPage; x78`dX
this.beginIndex = beginIndex; *UVo>;
} B zmmE2~*
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/** $^F
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* @return UMN3.-4K#
* Returns the beginIndex. YL_M=h>P
*/ -\OvOkr
publicint getBeginIndex(){ C:+-T+m[
return beginIndex; \a+.~_iL|
} 5\MCk "R!
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/** p.1@4kgK&r
* @param beginIndex K}e%E&|>
* The beginIndex to set. &eL02:[
*/ $9!2c /
publicvoid setBeginIndex(int beginIndex){ +ML4.$lc^
this.beginIndex = beginIndex; }w{6Ua
} [&e|:1
>?/Pl"{b
/** cn62:p]5
* @return m5c?A+@fZ
* Returns the currentPage. V(hM@ztN
*/ F7!g+LPc<
publicint getCurrentPage(){ ,Jm2|WKH
return currentPage; jlvh'y`
} '
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x3j)'`=15
/** J:<mq5[
* @param currentPage .ME>ICA
* The currentPage to set. a<c]N:1
*/ dux.Z9X?
publicvoid setCurrentPage(int currentPage){ xeo5)
this.currentPage = currentPage; u^HC1r|%
} ^U"$uJz!c
#NU@7Q[4
/** 5bKBVkJ'
* @return wKxw|Fpn
* Returns the everyPage. Nm;yL
*/ *3.K; Ic;
publicint getEveryPage(){ =lB+GS%
return everyPage; '3BBTr%aZ
} 7Gwn ,&)
HSXv_
/** S$~T8_m^U
* @param everyPage #0HZ"n
* The everyPage to set. d 8YP<"V&
*/ MI^@p`s
publicvoid setEveryPage(int everyPage){ tB S+?N
this.everyPage = everyPage; Blw AD
} +,7nsWV
yx0wR
/** O;zq(/,-l
* @return I5#KLZVg
* Returns the hasNextPage. WP*xu-(:
*/ k }amSsE
publicboolean getHasNextPage(){ f4%Z~3P
return hasNextPage; Z^tTR]u\$
} *Ubsa9'fS
Y~E
8z
/** `_YXU
* @param hasNextPage <{ZDD]UGs0
* The hasNextPage to set. ltQo_k
*/ i}u,_
}
publicvoid setHasNextPage(boolean hasNextPage){ (AYzN3
?D
this.hasNextPage = hasNextPage; b+=@;0p*6B
} !wbO:py[8>
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/** s2Z'_rT
* @return #:B14E
* Returns the hasPrePage. )RUx
*/ ` nd/N#
publicboolean getHasPrePage(){ 77 g<`}{
return hasPrePage; [3K& cX}B
} pc/x&VY%
M Ewa^
/** [TX1\*W
* @param hasPrePage g=#Cc(
q
* The hasPrePage to set. ()'yY^
*/ .1{:Q1"S
publicvoid setHasPrePage(boolean hasPrePage){ "A(D}~i
this.hasPrePage = hasPrePage; PiwMl)E|!
} |WkWZZ^
V; pRw`
/** 'zJBp 9a%
* @return Returns the totalPage. Ez1-Nx
* ylGT9G19
*/ ?^3Y+)}
publicint getTotalPage(){ ,=a+;D]'
return totalPage; ]F{F+r
} XY`{F.2h
XWq`MwC9
/** }HCt=W`
* @param totalPage EpW89X
* The totalPage to set. 5'<J@3B
*/ I]@QhCm0
publicvoid setTotalPage(int totalPage){ p=XEMVqm
this.totalPage = totalPage; /wi*OZ7R
} C1`fJhy
&gLXS1O
} 9kzJ5}
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uQhI)
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=L\&}kzB
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 ZGw6Bd_I
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个PageUtil,负责对Page对象进行构造: +@^FUt=tq
java代码: :
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/*Created on 2005-4-14*/ :Z[|B(U
package org.flyware.util.page; h
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Gh5 3Pne
import org.apache.commons.logging.Log; 1Y:JGon
import org.apache.commons.logging.LogFactory; ?vBMx _0
H2S/!Q;K
/** $jg~a
* @author Joa ]>/oo =E
* "8$Muwm
*/ jX7;hQ+P
publicclass PageUtil { )%JjV(:
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privatestaticfinal Log logger = LogFactory.getLog FrsXLUY
&c^tJ-s
(PageUtil.class); \zJb}NbnT
ms&6N']
/** r0Zj'F_e
* Use the origin page to create a new page D!DL6l`
* @param page P(bds
* @param totalRecords 84_Y+_9
* @return *kt|CXxAS8
*/ *qA:%m3
publicstatic Page createPage(Page page, int <lZVEg
s7(1|}jh
totalRecords){ v=_Ds<6n
return createPage(page.getEveryPage(), en"\2+{Cg
}U^iVq*
page.getCurrentPage(), totalRecords); Xf;_r+;
} mwMc AUD]2
,`ba?O?*G
/** ?>1wZ
* the basic page utils not including exception i'B$Xr
Nh01NY;
handler g;7W%v5wqk
* @param everyPage N(kSE^skOa
* @param currentPage ?X+PNw|pf
* @param totalRecords C1uV7t*\
* @return page zWrynJ}s
*/ L0R$T=~%)
publicstatic Page createPage(int everyPage, int %KPQ|^WE
F@KtRUxE
currentPage, int totalRecords){ q8)wAl
everyPage = getEveryPage(everyPage); o]eG+i6g]
currentPage = getCurrentPage(currentPage); C{G;G@/7
int beginIndex = getBeginIndex(everyPage, Byh!Snoe
,:{+-v(
currentPage); `k7X|
int totalPage = getTotalPage(everyPage, SAU` u]E
`[&%fTW+
totalRecords); Z kBWVZb
boolean hasNextPage = hasNextPage(currentPage, 50dx[v8
ub2B!6f a
totalPage); JkEITuTth
boolean hasPrePage = hasPrePage(currentPage); sD9OV6^{?K
g^{a;=
returnnew Page(hasPrePage, hasNextPage, dtBr#Te
everyPage, totalPage, fRwr}n'
currentPage, XaaR>HljJ
F9>"1
beginIndex); 4,&f#=Y
} 1*f/Y9 Z
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privatestaticint getEveryPage(int everyPage){ JF'<""
return everyPage == 0 ? 10 : everyPage; PB) vE
} ctPT=i60
&"=O!t2
privatestaticint getCurrentPage(int currentPage){ / <+F/R'=O
return currentPage == 0 ? 1 : currentPage; }&]T0U`@
} tlYB'8bJY
] I5&'#%2
privatestaticint getBeginIndex(int everyPage, int bduHYs+rq
hb(H-`16
currentPage){ ex.^V sf_
return(currentPage - 1) * everyPage; lm*C:e)4A
} ./<giTR:p
TCK#bJ
privatestaticint getTotalPage(int everyPage, int {]iM5?
:|-^et]a8
totalRecords){ I5]58Ohx
int totalPage = 0; s6D Pb_,
9fYof
if(totalRecords % everyPage == 0) +1K=]#a
totalPage = totalRecords / everyPage; !FQS9SoO9
else V"T5<HA9
totalPage = totalRecords / everyPage + 1 ; w6ck wn,
9R:?vk4
return totalPage; a_zf*;
} 3x=NSe|f
L% T%6p_
privatestaticboolean hasPrePage(int currentPage){ [KMS/'; ]
return currentPage == 1 ? false : true; [;#^h/5E
} xs?]DJj
)h,}v()qc#
privatestaticboolean hasNextPage(int currentPage, bRJ]avR
^vZu[m
int totalPage){ (hIe!"s*
return currentPage == totalPage || totalPage == pIPjTQ?cq
Gb.}af#v
0 ? false : true; ^Yo2 R
} Pa{bkr
?{~. }Vn
p3B_NsXVZ
}
UoJMOw[
PI)uBA;
BPu>_$C
Hiih$O+
$gdGII&n
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 5N907XVu
%1M!4**W
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7U-?Rd
3=_to7]
做法如下: [bEm D
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0C717
rUmnv%qTS
的信息,和一个结果集List: ^ lG^.
java代码: ze`qf%
hOe$h,E']
q X]ej2
/*Created on 2005-6-13*/ _<jccQ
package com.adt.bo; Mvk#$:8e
%p};Di[V
import java.util.List; T_qh_L3
%sS7o3RW\
import org.flyware.util.page.Page; zU#
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KvEZbf3f
/** Ifj%" RI
* @author Joa !<^`Sx/+
*/ |RI77b:pX
publicclass Result { 7T?7KS
P#2;1ki>
private Page page;
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=@k3*#\
private List content; %/wfY Rp*
e{,[\7nF
/** WhL1OG
* The default constructor .DcuJC=
*/ 5O"wPsl
public Result(){ _1?Fyu&<5
super(); mGUl/.;yp-
} yXA]E.K!
Xqas[:)7+
/** LiD-su
D
* The constructor using fields MM Nz2DEy[
* JmVha!<qk
* @param page ;%PdSG=U
* @param content ]I0(_e|z}
*/ +isaqfy/
public Result(Page page, List content){
\4&FW|mx
this.page = page; Gp))1b';
this.content = content; ?[q.1O
} &?7+8n&+
[>f4&yY
/** @0rwvyE=+3
* @return Returns the content. 3WF6bJN
*/ _xXDvBU
publicList getContent(){ jz$83TB-
return content; bq`0$c%hN
} |y7#D9m
%LZf=`:(
/** d:=:l?
* @return Returns the page. 2BIOA#@t
*/ veGRwir
public Page getPage(){ ]ipltR7k
return page; "G!V?~;
} :#p!&Fi
tL@m5M%:N2
/** N
@sVA%L.
* @param content -%)8=
* The content to set. rDWqJ<8
*/ W=
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public void setContent(List content){ y'pX/5R0
this.content = content; #oD*H:%*
} ^k}jPc6
#&c}in"!
/** }!g^}BWWp
* @param page <ba+7CK]w
* The page to set. kzb1iBe 6m
*/ iG;GAw|E
publicvoid setPage(Page page){ Xa32p_|5~
this.page = page; @Y2&v956
} ]Q\/si&
} ?{I]!gI
zbL6TP@=
:j0r~*z-
(s.S
n(E
ur2`.dY>3"
2. 编写业务逻辑接口,并实现它(UserManager, !ZlNPPrq}
&za~=+
UserManagerImpl) ssC5YtF7X
java代码: tmI2BBv
goV[C]|
BpKgUwf;C
/*Created on 2005-7-15*/ A PR%ZpG
package com.adt.service; 6?c(ue iL[
I~>L4~g)
import net.sf.hibernate.HibernateException; h47l;`kD-#
#0j,1NpL
import org.flyware.util.page.Page; xN#. Pm~
B]YY[i
import com.adt.bo.Result; $?u ^hMU=
y(RK|r
/** 0Ie9T1D=
* @author Joa .v:K`y;f\(
*/ ]%5DuE\M8\
publicinterface UserManager { W=EvEx^?%
AyMMr_q
public Result listUser(Page page)throws hol54)7$3:
Ng3 MfbFG
HibernateException; UN}jpu<h
xd H*[
} ]OOL4=b
0oi
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K}U}h>N
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java代码: m,U`hPJ
z_p/.kQ'5
6"W~%FSJX
/*Created on 2005-7-15*/ }]H_|V*f
package com.adt.service.impl; oA&V,r
XK>/i}y
import java.util.List; WeTs va+
ymBevL
import net.sf.hibernate.HibernateException; dZ7+Iw;m
/*bS~7f1
import org.flyware.util.page.Page; aMFUJrXo
import org.flyware.util.page.PageUtil; r^k:$wJbRK
[a*m9F\ ,
import com.adt.bo.Result; rnVh
]xJ
import com.adt.dao.UserDAO; ?1(' s0s\,
import com.adt.exception.ObjectNotFoundException; {qCmZn5
import com.adt.service.UserManager; p_jDnb#
)-2o}KU]>
/** 1;[\xqJ
* @author Joa :hG?} [-2
*/ !\H!9FR
publicclass UserManagerImpl implements UserManager { vb}; _/#?
0*"auGuX
private UserDAO userDAO; EIwTx:{F
V>j6Juh
/** lV-7bZ
* @param userDAO The userDAO to set. )dJaF#6j
*/ RvYH(!pQ
publicvoid setUserDAO(UserDAO userDAO){ # a
'h,
this.userDAO = userDAO; m[C-/f^u|
} */n)_
+!V*{<K
/* (non-Javadoc) /)xG%J7H
* @see com.adt.service.UserManager#listUser u|7d_3 ::
i=-zaboo
(org.flyware.util.page.Page) 4XDR?KUM
*/ 9
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public Result listUser(Page page)throws @#}9?>UV
vS:%(Y"!<
HibernateException, ObjectNotFoundException { ;PJWd|3
int totalRecords = userDAO.getUserCount(); 0sRby!
if(totalRecords == 0) 4?X#d)L(
throw new ObjectNotFoundException . oUaq|O
*tjE#TW
("userNotExist"); 2i4FIS|z0
page = PageUtil.createPage(page, totalRecords); Xz0jjO,
List users = userDAO.getUserByPage(page); 0CxQ@~ttl
returnnew Result(page, users); A?3hNvfx
} lkV%
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} G|yX9C]R
>UpTMEQ
3mgFouX2x,
S?%V o* Y
8h~v%aZ1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 k`r}Gb
:*e0Z2=
询,接下来编写UserDAO的代码: 8f% @
3. UserDAO 和 UserDAOImpl: viAvD6e
java代码: N7*JL2Rnq
]YZ+/:#U7
_tL*sA>[~)
/*Created on 2005-7-15*/ > >wbyj8
package com.adt.dao; ;"&^ckP
zGu(y@o
import java.util.List; gqJ&Q
t#f
%FQMB
import org.flyware.util.page.Page; %lV&QQa
%L{ H_;z
import net.sf.hibernate.HibernateException; j_\sdH*r
kqSCKY1
/** {!xPq%
* @author Joa &~U8S^os
*/ BG"~yyKA
publicinterface UserDAO extends BaseDAO { Tn/T:7C
iqghcY)
publicList getUserByName(String name)throws !'B.ad
i)\`"&.j>N
HibernateException; tOwwgf
O%A:2Y79
publicint getUserCount()throws HibernateException; Nc[>CgX"@
~o%|#-S
publicList getUserByPage(Page page)throws 6!/e_a
h/`OG>./
HibernateException; Oe^3YOR#j{
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} EKk~~PhW 8
{.z2n>1J{T
AShJtxxa
tz&=v,_jc
\^?BC;s^C
java代码: }?#<)|_5
\rcbt6H
6J6MR<5'
/*Created on 2005-7-15*/ ?)7uwJsH
package com.adt.dao.impl; RP7e)?5$s
/+P
4cHv]F
import java.util.List; @h
X
vyERt^z
import org.flyware.util.page.Page; d37l/I
T%KZV/
import net.sf.hibernate.HibernateException; %]>c4"H
import net.sf.hibernate.Query; WhSQ>h!@s
0X`Qt[
import com.adt.dao.UserDAO; ss% ahs
jio1#&
/** p(%7|'
* @author Joa Dz]&|5'N
*/ "}Ch2K
public class UserDAOImpl extends BaseDAOHibernateImpl A(W%G|+
<dD}4c+/t
implements UserDAO { ~kYUp5f
?BQZ\SXU
/* (non-Javadoc) X7{ueP#L
* @see com.adt.dao.UserDAO#getUserByName Q4TI '/
EkEM|<GNd
(java.lang.String) AASw^A3p
*/ z*YkD"]B
publicList getUserByName(String name)throws %z J)mOu
NM/?jF@j*
HibernateException { 5Qo\0YH
String querySentence = "FROM user in class ~LuZpV
N/TUcG|m\
com.adt.po.User WHERE user.name=:name"; }qG{1Er
Query query = getSession().createQuery &'N{v@Oi)
d%81}4f:
(querySentence); ^u:7U4
query.setParameter("name", name); A0cC)bd&
return query.list(); X +*@
} m-dne/%_
@ _U]U
/* (non-Javadoc) MJV)|
2C
* @see com.adt.dao.UserDAO#getUserCount() Iu jly f
*/ ?a7PxD.
publicint getUserCount()throws HibernateException { n wToZxHZ~
int count = 0; >,y291p2
String querySentence = "SELECT count(*) FROM W @`Nn*S
K\nN2y
user in class com.adt.po.User"; *O#%hTYq
Query query = getSession().createQuery 5.]+K<:h"A
vJ7I
[Z
(querySentence); LgjL+w19
count = ((Integer)query.iterate().next IwKhun
^L+*}4Dr
()).intValue(); b>hNkVI
return count; =;7gxV3;
} +b.<bb6
(LA%q6
/* (non-Javadoc) JaXT
B"e
* @see com.adt.dao.UserDAO#getUserByPage 75r>~@)*
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(org.flyware.util.page.Page) Ha@'%<gFe
*/ sk\U[#ohH
publicList getUserByPage(Page page)throws 1% ]|O
1LZ?!Lw
HibernateException { (#BkL:dg
String querySentence = "FROM user in class e Pq(:ih
o=_:g >5
com.adt.po.User"; Yewn
Query query = getSession().createQuery Al09R,I;
wV+ W(
(querySentence); }tF/ca:XPQ
query.setFirstResult(page.getBeginIndex()) @ H=
d8$
.setMaxResults(page.getEveryPage()); TUIj-HSe
return query.list(); 81eDN6
M\
} jA$g0>
(8TB*BhQ_
} F^7qLvh
h$)(-_c3
7[h_"@_A7
IROX]f}r (
sd9$4k"
至此,一个完整的分页程序完成。前台的只需要调用 &IsQgS7R
I$/*Pt];
userManager.listUser(page)即可得到一个Page对象和结果集对象 /_<`#?5T(
A'r 3%mC
的综合体,而传入的参数page对象则可以由前台传入,如果用 *p:`F:
yTzP{I
webwork,甚至可以直接在配置文件中指定。 oJa6)+b(3
s3qWTdM
下面给出一个webwork调用示例: CT,caa
java代码: cpvN
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q9cmtZrm
?3X!
/*Created on 2005-6-17*/ @)s;u}H
package com.adt.action.user; (uW/t1
D FDC'E
import java.util.List; e9e%8hL
,<?iL~> %
import org.apache.commons.logging.Log; :K.%^ag=j
import org.apache.commons.logging.LogFactory; ^?PU:eS
import org.flyware.util.page.Page; f?8cO#GU
dv=y,q@W
import com.adt.bo.Result; 7pMl:\
import com.adt.service.UserService; vzV,}
S*c
import com.opensymphony.xwork.Action; "<o[X ?u
=|>CB
/** 0\v98g<[+
* @author Joa 1=BDqSZ@9
*/ X"WKgC g$
publicclass ListUser implementsAction{ OS8 ^mC
UjibQl3:m
privatestaticfinal Log logger = LogFactory.getLog 5`qt82Qm
&y`
MDyXz
(ListUser.class); ^0"^Xk*
3t<XbHF9
private UserService userService; z _qy>
jVP70c
private Page page; n]M1'yU
v|5:;,I
privateList users; hZGoiWC
F) w.q
/* !iKR~&UpAL
* (non-Javadoc) { 3``T o$
* aE}1~`
* @see com.opensymphony.xwork.Action#execute() zJ{?'kp
*/ 6#~"~WfPQ
publicString execute()throwsException{ DLMG<4Cd~
Result result = userService.listUser(page); {FzL@!||
page = result.getPage(); _\E{T5
users = result.getContent(); gfE<XrG
return SUCCESS; Xx{ho4qq
} KTn,}7vZ
U3r[ysf
/** TR!^wB<F
* @return Returns the page. <>aBmJs4
*/ 5 e:Urv77
public Page getPage(){ )6|7L)Dk
return page; `(A6uakd
} =PHl|^
X!5N2x
/** vQrce&
* @return Returns the users. ,4y'(DA
*/ ZJ(/cD
publicList getUsers(){ Z=%+U _,
return users; ?f v?6r
} qGMM3a)Q
';`fMcN
/** Ke-Q>sm2Q
* @param page M0!;{1
* The page to set. +3.Ik,Z}zq
*/ N[4v6GS
publicvoid setPage(Page page){ }HS:3Dt
this.page = page; ?]gZg[
} @C)O[&Sk
lhg3
}dW
/** T!$7:% D
* @param users zb9^ii$g
* The users to set. jB }O6u[%
*/ &d`T~fl|
publicvoid setUsers(List users){ 0
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this.users = users; H"(:6
`
} MhC74G
G)gf +)W
/** A(duUl~
* @param userService !mFo:nQ)}
* The userService to set. ln.kEhQ3B
*/ 8D]:>[|E
publicvoid setUserService(UserService userService){ n+@}8;oeP
this.userService = userService; g+/%r91hZ
} !-
f>*|@
} lJ]r%YlF
!f_GR Pj'
P# 2&?.d\
M<JJQh5
p>v,b&06
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, -Hzn7L
^|}C!t+
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 2{s ND
bHlG(1uf
么只需要: b~06-dk1
java代码: ulFU(%&
o;Ijv\Em
4W8rb'B!Ay
<?xml version="1.0"?> |Hn[XRsf
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork q!W~>c!
>V(>2eD'S
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 3(P^PP8
475yX-A
1.0.dtd">
N>`+{
"M6a_rZ2W
<xwork> FW7+!A&F
Ff>Y<7CQ
v
<package name="user" extends="webwork- !s,<hU#
c5P52_@
interceptors"> c?)
pn9
6A M,1
<!-- The default interceptor stack name l^xkXj
qGkrG38K
--> ~C5iyXR
<default-interceptor-ref $gDp-7
n ! qm
name="myDefaultWebStack"/> $N;!. 5lX3
B%6bk.
<action name="listUser" L5T)_iQ5
^
vI|
class="com.adt.action.user.ListUser"> R+]p
-NI^
<param %9M; MK
D{o1G?A
name="page.everyPage">10</param> yP0P-8
<result iM2
EEC
fEs957$
name="success">/user/user_list.jsp</result> `'Ta=kd3
</action> ;t%L(J
|PH]0.m5
</package> !~UI~-i'
OfTcF_%
</xwork> xmKa8']x
yG&kP:k<
<6/XE@"
N(Y9FD;H
{%D
"0* ^
&_4A6
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 UTA0B&aB
+lJuF/sS8m
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。 37p0*%a":
#BS]wj2#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 z+" :,#
}#!o^B8
v ;MI*!E
_zh}%#6L
UShn)3F
我写的一个用于分页的类,用了泛型了,hoho U]vNcQj
(/YC\x?
java代码: mk\U wv
i?=3RdP/R1
{DN c7G
package com.intokr.util; SNvK8,"g
$pk3d+0B
import java.util.List; i`&