Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3AglvGK7{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 71>,tq
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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 zy%0;%
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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 sVBr6
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。 d=meh4Y
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分页支持类: G3`9'-2q@c
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java代码: |/H?\]7
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package com.javaeye.common.util; DQ3L=
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import java.util.List; cD6 ^7QF
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publicclass PaginationSupport { +p63J
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publicfinalstaticint PAGESIZE = 30; _k26(rdI@-
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privateint pageSize = PAGESIZE; {J
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privateList items; MJqWc6{ n
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privateint totalCount; yyljyE
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privateint[] indexes = newint[0]; YC8IwyL'
@XolFOL"f"
privateint startIndex = 0; ,dTmI{@O
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public PaginationSupport(List items, int O^=+"O]
=?0v,;F9|
totalCount){ k9OGnCW\
setPageSize(PAGESIZE); wEM=Tr/h
setTotalCount(totalCount); ~WTk X(\
setItems(items); C
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setStartIndex(0); Sx QA*}N
} ObEz 0Rj
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public PaginationSupport(List items, int 3.?be.cq
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totalCount, int startIndex){ cZ?$_;=
setPageSize(PAGESIZE); YmaS,Q-
setTotalCount(totalCount); H}5WglV.
setItems(items); P'OvwA
setStartIndex(startIndex); =xIZJ8e
} Ve|:k5z
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public PaginationSupport(List items, int Y2QX<
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totalCount, int pageSize, int startIndex){ [ ,Go*r
setPageSize(pageSize); >*h+N?
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setTotalCount(totalCount); $~.YB\3
setItems(items); wxo
setStartIndex(startIndex);
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} H(
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publicList getItems(){ D?1fY!C:r
return items; WM
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} Lcpe*C x-
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publicvoid setItems(List items){ r)'vn[A
this.items = items; rnj$u-8
} K#wA ;
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publicint getPageSize(){ $!.>)n
return pageSize; :LNE?@
} q%dG>!
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publicvoid setPageSize(int pageSize){ 2uE<mjCt-r
this.pageSize = pageSize; w7?fJ")
} Y)X7*iTi'j
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publicint getTotalCount(){ mfQ#n!{ZH
return totalCount; 6^]|
} zg<-%r'$
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publicvoid setTotalCount(int totalCount){ l}z<q
if(totalCount > 0){ ]WDmx$"&e
this.totalCount = totalCount; MMFwT(l<1
int count = totalCount / `]eJF|"
Kt_oo[ey{
pageSize; :'Qiwf&
if(totalCount % pageSize > 0) ux&"TkEp
count++; %)JEYH7Z
indexes = newint[count]; w'H'o!*/
for(int i = 0; i < count; i++){ LBK{-(%
indexes = pageSize * (E0
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i;
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} Z;.-UXat
}else{ |NfFe*q0;8
this.totalCount = 0; =*,SD
} %PYl
} +'?Qph6o,7
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publicint[] getIndexes(){ a+^`+p/5
return indexes; `$6o*g>:
} lhN@,q
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.
publicvoid setIndexes(int[] indexes){ uDDa>Ka#+
this.indexes = indexes; X1|
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} 7s|'NTp
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publicint getStartIndex(){ ]<f)Rf">:`
return startIndex; RPz[3y
} h:%,>I%{
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publicvoid setStartIndex(int startIndex){ 7=l~fKu
if(totalCount <= 0) XNYA\%:5S
this.startIndex = 0; n$/|r
elseif(startIndex >= totalCount) x%B_v^^^
this.startIndex = indexes _gT65G~z
*4cuWkQ,
[indexes.length - 1]; /s\ mV
elseif(startIndex < 0) xE1?)
this.startIndex = 0; (g##wa)L
else{ fq7#rZCxX
this.startIndex = indexes <|Td0|x
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[startIndex / pageSize]; uBm"Xkxe|w
} }%< ?]
} ?XBdBR_"^
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publicint getNextIndex(){ s5VK
int nextIndex = getStartIndex() + Y6jyU1>
#dauXUKH
pageSize; #"gt&t9Q
if(nextIndex >= totalCount) \((iR>^|
return getStartIndex(); mrTf["K
else 2f,8Jnia
return nextIndex; S,&LH-ps
} O<m46mwM
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publicint getPreviousIndex(){ 'oa.-g 5
int previousIndex = getStartIndex() - +IdM|4$\1
'n &p5%
pageSize; k<9,Ypa
if(previousIndex < 0) )&c2+Y@
return0; !nmZ"n|}p
else P3oYk_oW
return previousIndex; $@AJg
} ,1-%C)
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} k[Em~>m
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抽象业务类 *p{p.%Qs:
java代码: j=0kxvp
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/** ^twyy9VR
* Created on 2005-7-12 YU,zQ V'
*/ 8lF9LZ8
package com.javaeye.common.business; {v"f){
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import java.io.Serializable; Kzev] er
import java.util.List; Kw fd
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import org.hibernate.Criteria; c &c
import org.hibernate.HibernateException; & 9e
import org.hibernate.Session; &8VH m?h
import org.hibernate.criterion.DetachedCriteria; {z o GwB
import org.hibernate.criterion.Projections; frcAXh9
import uP9b^LEoN
IOHWb&N6
org.springframework.orm.hibernate3.HibernateCallback; xU;SRB
import `I7s|9-=
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org.springframework.orm.hibernate3.support.HibernateDaoS D0J{pAJ
^#5'` #t
upport; U&3!=|j
b: (+d"S
import com.javaeye.common.util.PaginationSupport; -x?Z2EA!
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public abstract class AbstractManager extends zC*FeqFL<
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HibernateDaoSupport { 4K cEJlK5
TQ\#Z~CbK{
privateboolean cacheQueries = false; 7(/yyZQnZ
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privateString queryCacheRegion; B7Ket8<J
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publicvoid setCacheQueries(boolean DN^+"_:TB
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cacheQueries){ tMLiG4
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this.cacheQueries = cacheQueries; s}JifY`
}
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publicvoid setQueryCacheRegion(String xWLZlUHEu
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queryCacheRegion){ }w)}=WmD
this.queryCacheRegion = Lginps[la
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queryCacheRegion; 2dz)rjdO,
} 9>{ml&$
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publicvoid save(finalObject entity){ +At[[
getHibernateTemplate().save(entity); `K VSYC
} pg5W`4-F
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publicvoid persist(finalObject entity){ a@g
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getHibernateTemplate().save(entity); LcLHX
} gZHgL7@
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publicvoid update(finalObject entity){ .LAB8bg
getHibernateTemplate().update(entity); U/FysN_N!
} b!t[PShw^
7 @\i5
publicvoid delete(finalObject entity){ (KO]>!t
getHibernateTemplate().delete(entity); tF[)Y#
} &fRz6Hd
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publicObject load(finalClass entity, $,Q]GIC
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finalSerializable id){ vo Et\H
return getHibernateTemplate().load ;/NC[:'$D
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(entity, id); Sv=e|!3f[k
} L'Iw9RAJ
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publicObject get(finalClass entity, }r18Y6
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finalSerializable id){ Q~.t8g/
return getHibernateTemplate().get 7Z9'Y?[m
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(entity, id); o]V.6Ge-
} KKQT?/ {b
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publicList findAll(finalClass entity){ >/RFff]Fh0
return getHibernateTemplate().find("from f>xi (0
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" + entity.getName()); f5M;q;
} nN.Gn+Cl
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publicList findByNamedQuery(finalString Rkg)yme!N
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namedQuery){ %yc-D]P/
return getHibernateTemplate yQ^, >eh
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().findByNamedQuery(namedQuery); Kt qOA[6
} 2\&3x}@
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publicList findByNamedQuery(finalString query, L9^M?.a
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finalObject parameter){ mc`Z;D/mt
return getHibernateTemplate JXRU9`3)A
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().findByNamedQuery(query, parameter); Hr=|xw8.
} _'G'>X>}WU
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publicList findByNamedQuery(finalString query, E;`^`T40
`, ]ui*
finalObject[] parameters){ ab9ec Z
return getHibernateTemplate QoUdTIIL
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().findByNamedQuery(query, parameters);
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} H}_R `S
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publicList find(finalString query){ V=fh;p
return getHibernateTemplate().find `<~=6H
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(query); a6xo U;T
} }8YY8|]LI
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publicList find(finalString query, finalObject {A< 9 61
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parameter){ u^MRKLn
return getHibernateTemplate().find vw:GNpg'R6
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(query, parameter); pl[@U<8aw
} 9MO=f^f-
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public PaginationSupport findPageByCriteria IUEpE9_
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(final DetachedCriteria detachedCriteria){ w
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return findPageByCriteria h*40jZ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <[
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} $mAC8a_Zu
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public PaginationSupport findPageByCriteria }ssja,;
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(final DetachedCriteria detachedCriteria, finalint ^$%
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startIndex){ <FU?^*~
return findPageByCriteria _#r00Ze
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(detachedCriteria, PaginationSupport.PAGESIZE, ZB)R4
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startIndex); J]Z~.f="
} Y-y yg4JH
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public PaginationSupport findPageByCriteria R3a}YwJFXF
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(final DetachedCriteria detachedCriteria, finalint V7nOT*N:Q
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pageSize, g<;::'6
finalint startIndex){ 2IM31 .
return(PaginationSupport) M.s'~S7y
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getHibernateTemplate().execute(new HibernateCallback(){ 2YKa <?_
publicObject doInHibernate KgkRs?'z
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(Session session)throws HibernateException { K.mxF,H
Criteria criteria = _9 '_w&
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detachedCriteria.getExecutableCriteria(session); x,U_x
int totalCount = RQo
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((Integer) criteria.setProjection(Projections.rowCount 300w\9fn&
4%ooJi|)
()).uniqueResult()).intValue(); u)<s*jk
criteria.setProjection Rb0I7~Z%'d
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(null); oS..y($TI
List items = io+V4m
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criteria.setFirstResult(startIndex).setMaxResults 8vR_WHsL
v
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(pageSize).list(); y{hy7w' d
PaginationSupport ps = =gQ9>An
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new PaginationSupport(items, totalCount, pageSize, =8?Kn@nMN
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startIndex); ?BfE*I$\h
return ps; (VjU ,'h
} `2@.%s1o=
}, true); R'tKJ_VI
} rniM[7K
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public List findAllByCriteria(final ^
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DetachedCriteria detachedCriteria){ bqAW
return(List) getHibernateTemplate [#q>Aq$11
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().execute(new HibernateCallback(){ l^Rb%?4Z
publicObject doInHibernate LQ# E+id&
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(Session session)throws HibernateException { [rT.k5_
Criteria criteria = [|KvlOvP
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detachedCriteria.getExecutableCriteria(session); @ps(3~?7
return criteria.list(); {jz`K1
} bu]"?bc
}, true); Y!CUUWM
} DHWz, M
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public int getCountByCriteria(final *$<W"@%^J
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DetachedCriteria detachedCriteria){ @9B*V~ <
Integer count = (Integer) \CMZ_%~wU
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getHibernateTemplate().execute(new HibernateCallback(){ )?$[iu7 s
publicObject doInHibernate D:_W;b)
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(Session session)throws HibernateException { rKrHd
Criteria criteria = f
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k9;^|Cm
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detachedCriteria.getExecutableCriteria(session); c;$4}U4
return aZWj52
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criteria.setProjection(Projections.rowCount 1g{Pe`G,
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()).uniqueResult(); P"Al*{:J
} q#W|fkfx+
}, true); hWT
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return count.intValue(); w*ans}P7
} .-d'*$
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} aM}9ZurI
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o(*\MTt?
`6Bx8CZ'I
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用户在web层构造查询条件detachedCriteria,和可选的 a:BW*Hy{\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )?F&`+
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PaginationSupport的实例ps。 VOEV[?>ss
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ps.getItems()得到已分页好的结果集 \|HEe{nA
ps.getIndexes()得到分页索引的数组 $*#a;w7\C
ps.getTotalCount()得到总结果数 %HUex
6!
ps.getStartIndex()当前分页索引 aAg Qv*
ps.getNextIndex()下一页索引 m'rDoly"62
ps.getPreviousIndex()上一页索引 ;b<w'A_1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 yf&g\ke
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 L;Ff(0x|
.shi?aWm
一下代码重构了。 :zY4phR
2"IV
我把原本我的做法也提供出来供大家讨论吧: 8y
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orGMzC 2
首先,为了实现分页查询,我封装了一个Page类: ={g)[:(C.
java代码: FZ"n6hWA
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/*Created on 2005-4-14*/ RkYdK$|K
package org.flyware.util.page; Y%KowgP\
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/** Na0^csPm
* @author Joa +kL7"
* aI=p_+.h
*/ q0.!T0i
publicclass Page { IZZAR
^'`b\$km-0
/** imply if the page has previous page */ )|~K&qn`
privateboolean hasPrePage; x~e._k=
5X{|*?>T
/** imply if the page has next page */ *u},(4Qf
privateboolean hasNextPage; m<CrkKfpG
f:>y'#P
/** the number of every page */ 69c4bT:b"
privateint everyPage; ?;XO1cs
Rl?1|$%
/** the total page number */ .9J^\%JD
privateint totalPage; -CvmZ:n
dbf<k%i6
/** the number of current page */ c8uaZvfW
privateint currentPage; wWl?c
;s+/'(*
/** the begin index of the records by the current OSBR2Z;=
M':-f3aT%
query */ V:\:[KcL^
privateint beginIndex; `B%%2p&
v;,W ^#`
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/** The default constructor */ "n%j2"TYJj
public Page(){ u
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} .p[uIRd`
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/** construct the page by everyPage f_c\uN@f
* @param everyPage o,7|=.-b
* */ T?8BAxC?K
public Page(int everyPage){ _XZ
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this.everyPage = everyPage; f"Sp.'@
} 0#V"
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/** The whole constructor */ 6#z8 %kaX
public Page(boolean hasPrePage, boolean hasNextPage, E !kN h
'2^}de!E
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int everyPage, int totalPage, ;Q{D]4
int currentPage, int beginIndex){ a\P :jgF
this.hasPrePage = hasPrePage; ,DFN:uf=l
this.hasNextPage = hasNextPage; J!C \R5\
this.everyPage = everyPage; @)pC3Vi^
this.totalPage = totalPage; 9qap#A
this.currentPage = currentPage; fFJ7Y+^
this.beginIndex = beginIndex; LUQ.=:mBR
} od
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7KgaXi3r
/** EQyX!
* @return nCYz];".
* Returns the beginIndex. hz/mNDE]
*/ U$y9f
publicint getBeginIndex(){ G&oD;NY@/
return beginIndex; m` 1dB%;?
} z^9oaoTl
[N,+mX
/** 7$*E0
* @param beginIndex Tvv>9gS
* The beginIndex to set. r_+Vb*|Y
*/ =%U&$d|@G
publicvoid setBeginIndex(int beginIndex){ )Jt. Z^J<
this.beginIndex = beginIndex; 6ALjM-t=V
} B-
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$%EX~$=m]-
/** [RBSUOF
* @return )@!fLAT
* Returns the currentPage. Y -it3q'Z
*/ 6 IvAs-%W
publicint getCurrentPage(){ -6)n QNj|
return currentPage; 'Xik2PaO
} h,\{s_b
-r*|N.5c
/** [8'?G5/n
* @param currentPage -mO#HZ Iq
* The currentPage to set. q^xG%YdPz+
*/ "M/c0`>C!i
publicvoid setCurrentPage(int currentPage){ {IOc'W-C#2
this.currentPage = currentPage; -nGcm"'6F
} =-^A;AO(
x-i,v"8
/** S(.J
* @return vjX,7NY?
* Returns the everyPage. 7rD 8
*/ i ;B^I8
publicint getEveryPage(){ 5WI
bnV@
return everyPage; d>[i*u,]/
} b36{vcs~
2)IM<rf'^
/** #?)6^uTW
* @param everyPage j \rGU){
* The everyPage to set. )j2#5`?"j
*/ B
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publicvoid setEveryPage(int everyPage){ & %/p;::A
this.everyPage = everyPage; K~#?Y,}O
} e6p3!)@P1
sqhMnDn[
/** I'xc$f_+
* @return J* !_O#
* Returns the hasNextPage. GP+=b:C{E
*/ b'pwRKpx
publicboolean getHasNextPage(){ _#\Nw0{
return hasNextPage; lL zR5445)
} @PM<pEve
D2VYw<tEA
/** |ru!C(
* @param hasNextPage A\?t^T
* The hasNextPage to set. T"99m^y
*/ Tu-lc)
publicvoid setHasNextPage(boolean hasNextPage){ g7323m1=
this.hasNextPage = hasNextPage; DOu^
} igL5nE=n
9Qszr=C0
/** |ufT)+:
* @return >V8!OaY5n
* Returns the hasPrePage. -aBhN~
*/ mh4 VQ9
publicboolean getHasPrePage(){ _wXT9`|3
return hasPrePage; }V]*FCpQ
} L4^/O29
i\lvxbp
/** ~6=6YP
* @param hasPrePage !{*yWpZ:
* The hasPrePage to set. 8^EWD3N`
*/ i'<hT
q4
publicvoid setHasPrePage(boolean hasPrePage){ 0Y!"3bw|
this.hasPrePage = hasPrePage; (}wPu&Is,C
} t{UVX%b
uKzx >\}?1
/** &'`C#-e@
* @return Returns the totalPage. iZk4KX
* X8v)yDtw
*/ a5Vlfx
publicint getTotalPage(){ {;Hg1=cm
return totalPage; y#
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} Lea4-Gc
UG44 oKB
/** .WSn Y71
* @param totalPage 41/civX>V
* The totalPage to set. 2Bi]t%<{
*/ i-w<5pGnf
publicvoid setTotalPage(int totalPage){ <mP_K^9c
this.totalPage = totalPage; 0Gj/yra9MO
} j)G%I y[`
8\E=p+C
} AHr^G'
De3;}]wC
c|:EMYS
aNM*=y`
wx-&(f
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 +)h# !/
zEQQ4)mA
个PageUtil,负责对Page对象进行构造: xBc$qjV
java代码: 2.JrLBhN
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O.#Rr/+)
/*Created on 2005-4-14*/ t{UWb~"
package org.flyware.util.page; 2@T0QJ
RF8,qz
import org.apache.commons.logging.Log; 8aQTm-{m
import org.apache.commons.logging.LogFactory; f-^*p
Uf_mwEE
/** 7#"y mE
* @author Joa Z}zka<y6K6
* OWz{WV.
*/ <NDV 5P
publicclass PageUtil { %1cxZxGT
o9ys$vXt*
privatestaticfinal Log logger = LogFactory.getLog #2\M(5d
Y&M {7
(PageUtil.class); x$Wtkb0<
&Odrq#o?R
/** xP9R
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* Use the origin page to create a new page IecD41%
* @param page 8WLh7[
* @param totalRecords y+wy<[u
* @return AvIheR
*/ B4*,]lS?
publicstatic Page createPage(Page page, int Ts, U T L
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totalRecords){ ,F!-17_vt
return createPage(page.getEveryPage(), )jwovS?V
f7 ew<c\
page.getCurrentPage(), totalRecords); 'M?pg$ta_V
} U4a8z<l$
kyJKai
/** p? +!*BZ
* the basic page utils not including exception ZQR)k:k7
A$~H`W<yxB
handler i+Ne.h
* @param everyPage q}'<[Wg
* @param currentPage <b4}
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* @param totalRecords _;x` 6LM
* @return page aFnyhu&W'
*/ ?=?*W7
publicstatic Page createPage(int everyPage, int 8%; .H-
Ozulp(8*
currentPage, int totalRecords){ 3?gfDJfE
everyPage = getEveryPage(everyPage); |J-tU)|1vl
currentPage = getCurrentPage(currentPage); B}y#AVSA
int beginIndex = getBeginIndex(everyPage, 4ke.p<dG
a~VW?wq
currentPage); <vs*aFq
int totalPage = getTotalPage(everyPage, S"+#=C
=%}(Dvjv
totalRecords); }f{5-iwD}
boolean hasNextPage = hasNextPage(currentPage, s)'+,lKw
"FE%k>aV@v
totalPage); f/kYm\Zc
boolean hasPrePage = hasPrePage(currentPage); #~rQ\A!4
,o
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returnnew Page(hasPrePage, hasNextPage, K)Ya%%6[U#
everyPage, totalPage, 55y}t%5
currentPage, $Zi{1w
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beginIndex); ( t"|XSF
} MD0d
INCanE`+
privatestaticint getEveryPage(int everyPage){ !t)uRJ
return everyPage == 0 ? 10 : everyPage; {)Zz4
} g p9;I*!
a*,V\l|6
privatestaticint getCurrentPage(int currentPage){ 2*-qEUl1
return currentPage == 0 ? 1 : currentPage; :E|+[}|
} RLw/~
t1#f*G5
privatestaticint getBeginIndex(int everyPage, int k9y/.Mu
>FFp"%%
currentPage){ 0!c/4^
return(currentPage - 1) * everyPage; kmJ<AnK
} z`J-J*R>d
A6;[r #C
privatestaticint getTotalPage(int everyPage, int ]3U|K .G
m KKa0"
totalRecords){ Y}\3PaUa
int totalPage = 0; H!y-o'Z
MqWM!v-M
if(totalRecords % everyPage == 0) #Guwbg
totalPage = totalRecords / everyPage; >G0ihhVt
else ]VN1Y)
totalPage = totalRecords / everyPage + 1 ; =*?XZA)c
;$r!eFY;
return totalPage; Nw1 .x
} *z'Rl'j9[
t/]za4w/
privatestaticboolean hasPrePage(int currentPage){ Z 2uU'T
return currentPage == 1 ? false : true; Hw#yw g
} Yk7^?W
LKud'
privatestaticboolean hasNextPage(int currentPage, !?B2OE
@nj`T{*.
int totalPage){ &4p~i Z
return currentPage == totalPage || totalPage == ?G5,x
%CrpUx
0 ? false : true; 61b<6r0o
} 'Te'wh=Y
|L)qH"Eo
X*r?@uK5
} /5XdZu6k`h
0NSCeq%;6q
rsK
b9G
U<yKC8
w 3L+7V,!
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。 $yZP"AsAR
!NhVPb,
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 @jr$4pM?
2$ \#BG
做法如下: (>om.FM
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Nm0|U.<
cl'qw##
的信息,和一个结果集List: yA<\?Ps
java代码: fqm6Pd{:(
`7
J4h9K
<
$rXQ
/*Created on 2005-6-13*/ J\ ?
package com.adt.bo; LC/%AbM
C:}"?tri
import java.util.List; .18MMzdN
];Bk|xJ/>
import org.flyware.util.page.Page; qS[nf>"
hTAZGV(
/** A6F/w
* @author Joa wo ) lkovd
*/ LkJ-M=y
publicclass Result { )}\J
n6GB2<y
private Page page; rdm&YM`J
["Jt2
private List content; A@ G%*\UZ
^<e(3S:
/** ~,84E [VV
* The default constructor >uz3 O?z P
*/ X
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public Result(){ K~\Ocl
super(); i"y @Aj!7
} :AC( \
Czd)AVK
/** ^pvnUODW[
* The constructor using fields ^{+_PWn
* ?w "zW6U
* @param page Mg{=(No
* @param content ohB@ij C!
*/ EYKV}`
public Result(Page page, List content){ *h"7!g
this.page = page; bX&=*L+h6
this.content = content; jL#`CD
} Bjsg!^X7
\w@ "`!%
/** $[*<e~?
* @return Returns the content. DqBiBH[%h
*/ mp>Ne6\Tu
publicList getContent(){ ,A!0:+
return content; p+1kU1F0
} YZ^;xV
HY7#z2L
/** ]hi5nA
* @return Returns the page. j |ZhGerp
*/ l>jNBxB|/A
public Page getPage(){ N/N~>7f
return page; um1xSf1Xv
} A#Jx6T`a
#?RT$L>n
/** i~EFRI@
* @param content MJI`1*(
* The content to set. &qae+p?
*/ [#C(^J*@c
public void setContent(List content){ ?hnxc0~P
this.content = content; R"qxT.P(
} `"qSr%|
nHF%PH#|o
/** OOj}CZ6
* @param page 18gApRa
* The page to set. O3["5
*/ 4oRDvn7f&
publicvoid setPage(Page page){ !"QvV6Lq\
this.page = page; Xg1QF^
} aO$I|!tl
} #w#:f
_tQR3I5
p;9"0rj,z
Bh<6J&<n
z[0B"f
2. 编写业务逻辑接口,并实现它(UserManager, }w/6"MJ[n
4,qhWe`/
UserManagerImpl) jq12,R2+)
java代码: JY6^pC}*
:c`Gh< u
vAjvW&'g
/*Created on 2005-7-15*/ (E]q>'X
package com.adt.service; ~~X-$rtU
i5jsM\1j
import net.sf.hibernate.HibernateException; 2N[/Cc2Tg/
q2~@z-q)b
import org.flyware.util.page.Page; Alpk5o5B
='<789wT
import com.adt.bo.Result; qv.s-@l8
3DS&-rN
/** Iju9#b6
* @author Joa F!&$Z
.
*/ |WDMyKf6J
publicinterface UserManager { D
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q=`i
public Result listUser(Page page)throws Dt=@OZW
KetNFwbUf
HibernateException; /V$U%0
Z2D^]
} @PAT|6
2*ByVK
HGlQZwf
~l"]J'jF"H
bn6WvC3?
java代码: <3C/t|s
, IDCbJ
=`Lci1#pu}
/*Created on 2005-7-15*/ u+5MrS[
package com.adt.service.impl; OV,t|
1paLxR5
import java.util.List; b.|k j
Lv m"!!
import net.sf.hibernate.HibernateException; )uu1AbT+e
9vI<\
Xa
import org.flyware.util.page.Page; T1=T
import org.flyware.util.page.PageUtil; ZfP$6%;_
SZ(]su:
import com.adt.bo.Result; z^^)n
import com.adt.dao.UserDAO; N|\Q:<!2_w
import com.adt.exception.ObjectNotFoundException; szC<ht?z
import com.adt.service.UserManager; X)b@ia'"Wp
7B{LRm6;Vu
/** d=d*:<Zx
* @author Joa 7oV$TAAf
*/ P+bA>lJd
publicclass UserManagerImpl implements UserManager { !!?TkVyEyM
~EtwX YkRZ
private UserDAO userDAO; x>$e*
]+A%37
/** Wmc@:
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* @param userDAO The userDAO to set. p(Ux]_s%
*/ \45F;f_r6
publicvoid setUserDAO(UserDAO userDAO){ bYAtUEv
this.userDAO = userDAO; .W
s\%S
} 1s/548wu
6W[~@~D=
/* (non-Javadoc) g0ks[ }f-
* @see com.adt.service.UserManager#listUser {ep(_1
Gy)2
(org.flyware.util.page.Page) xtO#reL"q?
*/ /odDJxJ
k
public Result listUser(Page page)throws .bY
R
`IV7\}I|
HibernateException, ObjectNotFoundException { R9\ )a2
int totalRecords = userDAO.getUserCount(); Yhte&,D"
if(totalRecords == 0) n#^ii/H
throw new ObjectNotFoundException e2qSU[
A<''x'\/
("userNotExist"); gy>B
5ie
page = PageUtil.createPage(page, totalRecords); 5.d[C/pRw
List users = userDAO.getUserByPage(page); sOVU>tb\'
returnnew Result(page, users); L Q0e@5
} L Iz<fB
7>lM^ :A
} .F},Z[a&
T/]f5/
.tcdqL-'
nO+R>8,Q
Jb*E6-9G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rXP~k]tC
_;M3=MTM9
询,接下来编写UserDAO的代码: ,pIh.sk7s*
3. UserDAO 和 UserDAOImpl: /mXxj93UA
java代码: lFl(Sww!\
#/B g5:
%
:h%i|
/*Created on 2005-7-15*/ 6=:s3I^
package com.adt.dao; `I.pwst8i-
d}Q%I
import java.util.List; pO92cGJ8
LU/;`In
import org.flyware.util.page.Page; EpH_v`
|'-%d^Z
import net.sf.hibernate.HibernateException; R.!.7dO
%Ai' 6
/** _&%FGcAS
* @author Joa T@A Qe[U'v
*/ *:"@
publicinterface UserDAO extends BaseDAO { mv7W03
dXfLN<nD>U
publicList getUserByName(String name)throws 0j;q^>
yd=b!\}WJ
HibernateException; *3)kr=x
+PS
jBO4!
publicint getUserCount()throws HibernateException; _b$ yohQ
M|NQoQ8q
publicList getUserByPage(Page page)throws .$@+ /@4
dIfy!B"
HibernateException; Y_K W9T_
NSM7n=
*nh
} @VPmr}p:{
u*/+cT
uP+VS>b
+Qf}&D_
H@1}_d
java代码: `Qjs{H
|]?zH~L
&r\8VEZq"
/*Created on 2005-7-15*/ \W]gy_=D{
package com.adt.dao.impl; .cbC2t95
YS_3Cq
import java.util.List; )2_[Ww|.
)+R n[MMp
import org.flyware.util.page.Page; v2_` iwE
. P+Qu
import net.sf.hibernate.HibernateException; ]IE Z?+F,
import net.sf.hibernate.Query; Ptf(p`
#*:^\z_Jd
import com.adt.dao.UserDAO; N<1+aL\
,yA[XAz~U
/** k/D{&(F ~
* @author Joa U(#JC(E-#
*/ Ulx]4;uzf
public class UserDAOImpl extends BaseDAOHibernateImpl SiUu**zC
nwh @F1|
implements UserDAO { *= ?|n
uZZRFioX|
/* (non-Javadoc) 1Dl6T\20
* @see com.adt.dao.UserDAO#getUserByName #-@uLc
>=|p30\b
(java.lang.String) ;0Pv49q
*/ nQoQNB
publicList getUserByName(String name)throws J|].h
?*%_:fB
HibernateException { |/vJ+aKq
String querySentence = "FROM user in class ykx^RmD`~
marZA'u%B1
com.adt.po.User WHERE user.name=:name"; Z Cjw)To(
Query query = getSession().createQuery U2A
82;Z
L- !1ybB^
(querySentence); 4A6Yl6\Y
query.setParameter("name", name); U!`iKy-
return query.list(); s<)lC;#e
} hd u2?v@
XIbZ_G^ +D
/* (non-Javadoc) 2Jio_Hk
* @see com.adt.dao.UserDAO#getUserCount() YT
Zi[/
*/ ?)y^ [9
publicint getUserCount()throws HibernateException { KGHSEZi]
int count = 0; BUJ\[/
String querySentence = "SELECT count(*) FROM `}$o<CJ
%KXiB6<4
user in class com.adt.po.User"; {VL@U$'oI
Query query = getSession().createQuery =y4dR#R(\
Pps-,*m
(querySentence); `om+p?j
count = ((Integer)query.iterate().next {PcJuRTHB
U~N7\Pa4
()).intValue(); <"J]u@|
return count; dy&UF,l6
} b1.*cIv}
N);w~)MYh
/* (non-Javadoc) wOl?(w=|
* @see com.adt.dao.UserDAO#getUserByPage WXl+w7jr
)&Oc7\J,
(org.flyware.util.page.Page) \ph.c*c
*/ $+!dP{
publicList getUserByPage(Page page)throws *iEtXv
a+E&{pV
HibernateException { );\c{QF
String querySentence = "FROM user in class AQlB_@ b
)ODF6Ag
com.adt.po.User"; W(`QbNJ
Query query = getSession().createQuery r8J 7zTD&
e "A"
(querySentence); o@Oz
a
query.setFirstResult(page.getBeginIndex()) .p&@;fZ
.setMaxResults(page.getEveryPage()); d]pb1ECuu
return query.list(); $(aq;DR
} c+9L6}D
?Gki0^~J
} hm`=wceK
d,b4q&^X8
d,V#5l-6
NQk aW)
xc:E>-
至此,一个完整的分页程序完成。前台的只需要调用 sjr,)|#[
-n|bi cP
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ae+)RBpc
G%<}TI1}
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;*<tU
n^t
;sZG=y@
webwork,甚至可以直接在配置文件中指定。 5ilGWkb`'X
E-bswUVaEE
下面给出一个webwork调用示例: `Y#At3{
java代码: q@|+`>h
n/+X3JJ
/BL:"t@-
/*Created on 2005-6-17*/ E.oJ[;
package com.adt.action.user; gg'1q3OjM
zfIo]M`
import java.util.List; uJ!&T
eUyF<j
import org.apache.commons.logging.Log; Ott6y
import org.apache.commons.logging.LogFactory; ?\}Gi(VVE
import org.flyware.util.page.Page; mmAm@/
Da=EAG-{7
import com.adt.bo.Result; Mt[yY|Ec|
import com.adt.service.UserService; BG>Y[u\N
import com.opensymphony.xwork.Action; "yn~axk7
@I_cwUO
/** CRb8WD6.
* @author Joa <$~lFV
*/ _gvFs%J
publicclass ListUser implementsAction{ !#tVQ2O
4CNrIF@
privatestaticfinal Log logger = LogFactory.getLog D*XrK0#Z`
QQ*sjK.(
(ListUser.class); J1?;'
2"Os9 KD
private UserService userService; f-ltV<C_
3[YG
BM(
private Page page; v, $r.g;
O\5%IfB'"
privateList users; /k#-OXP~
g 9_ zkGc7
/* z5+Pi:1w
* (non-Javadoc) 1|bXIY.J*
* +#}GmUwPG$
* @see com.opensymphony.xwork.Action#execute() eA/n.V$z
*/ $@g]?*L:
publicString execute()throwsException{ ~6[?=mOi'
Result result = userService.listUser(page); m5\T,
page = result.getPage(); w+M/VsL
users = result.getContent(); wu41Mz7
return SUCCESS; o<`vh*U@,4
} `KJ(. m
4ot<Uw5
/** xEb>6+-F@
* @return Returns the page. &qv~)ZM$
*/ ke4E1T-1n
public Page getPage(){ YW}$e W*
return page; i_Kwxn$
} 48^-]};
("$/sT
/** Z%t_1t
* @return Returns the users. VUb>{&F[
*/ L*@`i ]jl
publicList getUsers(){ uYJS=NGNA
return users; %xt9k9=vZ
} "TZq")-
(lk9](;L
/** TCr4-"`r-{
* @param page <2$vo
* The page to set. y Zafq"o
*/ ;kFD769DLw
publicvoid setPage(Page page){ ]e>qvSuYh
this.page = page; { 3G
} v 6 ~9)\!j
222 Y?3>@D
/** :4ryi&Y
* @param users I!x.bp~V!
* The users to set. |/Nh#
*/ (q)}`1d'
publicvoid setUsers(List users){ 7]=&Q4e4
this.users = users; #'L<7t
K
} =i/Df?
bA;OphO(
/** iaGA9l<b
* @param userService Fmk:[hMw
* The userService to set. Q(|@&83].
*/ yD\q4G
publicvoid setUserService(UserService userService){ umYsO.8
this.userService = userService; |IgR1kp+.
} Xp<q`w0I,
} &@~K8*tmK
|9*Rnm_
0~|0D#klB
aLk3Yg@X
b<h((]Q>^
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, 4:/]Y=)x
V!}I$JiJ
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 YteIp'T
|t,sK aL
么只需要: $BqiC!~
java代码: (tK_(gO
sh/,"b2!P
|G j.E
<?xml version="1.0"?> _@5Xmr
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork `<XS5h
h=
ym;]3<I?I[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- l*CulVX
g2OnLEF]s
1.0.dtd"> pPReo)
~q>jXi
<xwork> O=K
lc+Oo
Z{8%Cln
<package name="user" extends="webwork- D
T5d]MU
@iz Onc:
interceptors"> ]LE,4[VxRz
0h-NT\m
<!-- The default interceptor stack name <ZC.9
P`tOL#UeZL
--> \XDiw~0
<default-interceptor-ref SKG
U)Rn;
;qmnG3;Q
name="myDefaultWebStack"/> e$LC
+17!v_4^
<action name="listUser" h#1:ypA6l
5Tn<
class="com.adt.action.user.ListUser"> b9g2mWL\T
<param *|&Y ,H?
g *5_m(H
name="page.everyPage">10</param> 2dts}G
<result %1&X+s3
| W@ ~mrO
name="success">/user/user_list.jsp</result> N"9^A^w8k
</action> &A:&2sP8
Dj/Hz\
</package> Df"PNUwA"
T{prCM
</xwork> GcM1*)$ 4
:tWkK$
PYQ0&;z
lDS y$
LWr YKi
FH</[7f;@N
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 /#9P0@Y
b>5*G1
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。 1 |z4]R,<
yp~z-aRa
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 EH".ki=e
" ILF!z
E8C8kH]
gX"
^*jwe^
我写的一个用于分页的类,用了泛型了,hoho NXD-
!\ b-Ot(
java代码: 2K4Xu9-i:b
=t N}4
dr)*.<_+a(
package com.intokr.util; 2UQF:R?LQ
,RV>F_
import java.util.List; dPO"8HQ
H~*N:$C
/** 8B ,S_0!
* 用于分页的类<br> "s@Hg1
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Vc0j)3
* x,: k/]
* @version 0.01 9q ]f]S.L
* @author cheng t!4 (a0\$F
*/ R(t%/Hvs$
public class Paginator<E> { e@c8Ce|0
privateint count = 0; // 总记录数
/$93#$
privateint p = 1; // 页编号 J"#6m&R_q
privateint num = 20; // 每页的记录数 ZXLAX9|
privateList<E> results = null; // 结果 y%|E z
#0)TS
/** -qpvVLR,
* 结果总数 Wrbv<8}%c
*/ {^
BZ#)m|
publicint getCount(){ 3 85qQppz
return count; _I)TO_L;
} ty[%:eG#
zvN7aG
publicvoid setCount(int count){ O-0 5.
this.count = count; (4z_2a(Dl,
} bv41et+Kb
A|Ft:_Y
/** =2*2$
* 本结果所在的页码,从1开始 l`75BR
*
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* @return Returns the pageNo. 3hkEjR
*/ GRpwEfG
publicint getP(){ C-_u`|jQ
return p; [6\O
<-?
} UQ hD8Z'I.
Y q/vym-O5
/** ZHwl 9n#m
* if(p<=0) p=1 a^G>|+8
* 3f>9tUWhTy
* @param p m[l&&(+J,
*/ ao7M([ff
publicvoid setP(int p){ vh|m[ p
if(p <= 0) I 8
?
p = 1; )-XD=
]
this.p = p; \k$cg~
} w3iX "w
("f~gz<<
/** +pUYFDwFx
* 每页记录数量 >y}> 5kv
*/ M~X~2`fFH
publicint getNum(){ fyZtwl@6w#
return num; $v8T%'p+
} _x-2tnIxXv
\HMuVg'Q
/** ~urk
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* if(num<1) num=1 .K_50%s
*/ Ug[0l)
publicvoid setNum(int num){ ?r$&O*;
if(num < 1) J,h'eY5
num = 1; q@mZ0D-
this.num = num; u3 X!O
} 7 }t=Lx(
wlwgYAD
/** \*fXPJ4
* 获得总页数 .dc|?$XV
*/ hZ>1n&[@
publicint getPageNum(){ G{+zKs}~
return(count - 1) / num + 1; 5:~ zlg
} n>o=RQ2
_Fkb$NJ"]Q
/** us#ji i.<
* 获得本页的开始编号,为 (p-1)*num+1 M(} T\R
*/ Pr/q?qZY
publicint getStart(){ ;F2"gTQS
return(p - 1) * num + 1; 5uM`4xkj
} ![[:Z
2 I.Q-'@
/** =4/K#cQ
* @return Returns the results. 9:!V":8q
*/ yTWicW7i
publicList<E> getResults(){ Q2gz\N
return results; On;7
} 9KL)5_6 M
[xDn=)`{V
public void setResults(List<E> results){ LD;!
s
this.results = results; m.yt?`
} u~'j?K.^
aqP"Y9l
public String toString(){ gue~aqtJ
StringBuilder buff = new StringBuilder YQ-V^e6
D'Kiy
(); &