Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3z/O`z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 j"$b%|
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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 :#!F 7u
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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 t;a}p_>
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分页支持类: 7[?}kG
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java代码: C`1\$U~%
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package com.javaeye.common.util; {Z~VO
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import java.util.List; V{aIhH>P
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publicclass PaginationSupport { P@T $6%~
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publicfinalstaticint PAGESIZE = 30; Y<$"]@w
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privateint pageSize = PAGESIZE; wCE fR!i
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privateList items; v_F?x!
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privateint totalCount; x?k |i}Q
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privateint[] indexes = newint[0]; c$Nl-?W
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privateint startIndex = 0; ; >hPHx
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public PaginationSupport(List items, int H-y-7PW*~
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totalCount){ Q ]koj!mMl
setPageSize(PAGESIZE); O7_NXfh|
setTotalCount(totalCount); K]azUK7
setItems(items); }j<_JI
setStartIndex(0); #(}_2x5
} b:d.Lf{y7
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public PaginationSupport(List items, int xx2:5
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totalCount, int startIndex){ `fE:5y
setPageSize(PAGESIZE); `];[T=
setTotalCount(totalCount); L$07u{Q
setItems(items); 9!OCilG
setStartIndex(startIndex); .;sPG
} hdDI%3vk3
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public PaginationSupport(List items, int ]$k
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totalCount, int pageSize, int startIndex){ [8g\pPQ
setPageSize(pageSize); !~DkA7i 55
setTotalCount(totalCount); HOI`F3#XI
setItems(items); w5G34[v
setStartIndex(startIndex); vP;tgW9Qk
} .\\#~r`t 3
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publicList getItems(){ Jx[e{o)o
return items; )uJ`E8>-
} Z`h_oK#y15
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publicvoid setItems(List items){ dufHd
this.items = items; F,$$N>
} AyXKhj#Ml
F>{uB!!L4
publicint getPageSize(){ BP><G^
return pageSize; y,eoTmaI
} TgG)btQ
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publicvoid setPageSize(int pageSize){ ep1Ajz.l
this.pageSize = pageSize; g(/O)G.
} [9Hm][|Ph
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publicint getTotalCount(){ f*f9:xUY
return totalCount; UE](`|4H
} 9K_HcLO%y
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publicvoid setTotalCount(int totalCount){ b<MMli
if(totalCount > 0){ os+wTUR^
this.totalCount = totalCount; (
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int count = totalCount / 8#3cmpx4
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pageSize; iFT3fP'> 5
if(totalCount % pageSize > 0) 4SO{cst
count++; SQCuY<mD
indexes = newint[count]; E0'6 !9y
for(int i = 0; i < count; i++){ ::t!W7W
indexes = pageSize * PU\q.y0R
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i; TV2:5@33
} a.ME{:a%
}else{ 667tL(
this.totalCount = 0; g)Uh
} hRiGW_t
} qt)mUq;>
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publicint[] getIndexes(){ m=y)i]=1
return indexes; ?|F;x"
} 3Q6#m3AWY
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publicvoid setIndexes(int[] indexes){ pfIvBU?
this.indexes = indexes; Q 7?4GxMj
} 0;`PHNBq
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publicint getStartIndex(){ +1A<kJ
return startIndex; .h }D%Qa
} ZuON@ (
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publicvoid setStartIndex(int startIndex){ P,], N)
if(totalCount <= 0) D{}\7qe
this.startIndex = 0; &Vm[5XW
elseif(startIndex >= totalCount) .5zJ bZ9
this.startIndex = indexes ;]e"bX
m)2U-3*iX
[indexes.length - 1]; -M9
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elseif(startIndex < 0) ?q6eV~P
this.startIndex = 0; %iML??S
else{ ~nlY8B(
this.startIndex = indexes &wvv5Vd
L 32ki}2
[startIndex / pageSize]; 79fg%cSb
} [! o-F;
} kE|#mI[>
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publicint getNextIndex(){ ;bbEd'
int nextIndex = getStartIndex() + ,1kV9_x
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pageSize; ;W"[,#2TM
if(nextIndex >= totalCount) r
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return getStartIndex(); 3sNq3I
else [\p0eUog/
return nextIndex; hWJc
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} IVKE dwA
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publicint getPreviousIndex(){ _E 8SX
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int previousIndex = getStartIndex() - h Nwb.[
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pageSize; O*7~t17
if(previousIndex < 0) @
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return0; [HfFC3U
else G)`MoVH1
return previousIndex; LdL\B0^l
} djp(s$:{4
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} C\[UAxZ3X
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抽象业务类 .})8gL7V
java代码: %(6Wr E5F6
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/** }8e%s;C
* Created on 2005-7-12 :
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*/ '{~ej:
package com.javaeye.common.business; v|z1nD!?]
u,q#-d0g;
import java.io.Serializable; ZvJx01F{
import java.util.List; tIw4V^'|
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import org.hibernate.Criteria; cR} =3|t
import org.hibernate.HibernateException; pcG q
import org.hibernate.Session; l+,rc*-j0
import org.hibernate.criterion.DetachedCriteria; X35hLp8 M
import org.hibernate.criterion.Projections; Z5K,y19/~
import 3WHH3co[
w4mL/j
org.springframework.orm.hibernate3.HibernateCallback; |d8o<Q
import 9|,AhyhO
(@9-"W
org.springframework.orm.hibernate3.support.HibernateDaoS `x3c},'@k
&~EOM
upport; |V5H(2/nk
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import com.javaeye.common.util.PaginationSupport; ho. a93
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public abstract class AbstractManager extends {s]eXc]K}
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HibernateDaoSupport { :KwYuwYS
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privateboolean cacheQueries = false; ^q$sCt}
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privateString queryCacheRegion; c"r( l~fc
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publicvoid setCacheQueries(boolean :>z0m0nI\
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cacheQueries){ h";sQ'us
this.cacheQueries = cacheQueries; 5Z'pMkn3
} pe8MG(V
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publicvoid setQueryCacheRegion(String KAGq\7
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queryCacheRegion){ 9,IGZ55C
this.queryCacheRegion = t<-Iiq+tL
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queryCacheRegion; d>f5Tl\E
} ~rD* Y.
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publicvoid save(finalObject entity){ MLl:)W*
getHibernateTemplate().save(entity); Q6E80>
} 4U3T..wA
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publicvoid persist(finalObject entity){ 1x]G/I*
getHibernateTemplate().save(entity); /}wGmX! -!
} ygHNAQG~
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publicvoid update(finalObject entity){ \W4SZR%u
getHibernateTemplate().update(entity); OWU]gh@r
} c8'?Dd
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publicvoid delete(finalObject entity){ TSeAC[%pL
getHibernateTemplate().delete(entity); e>/PW&Z8Z
} wp$=lU{B
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publicObject load(finalClass entity, ]M.ufbg uq
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finalSerializable id){ ]GJskBm
return getHibernateTemplate().load 'sC{d&c
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(entity, id); ^(%>U!<<%,
} .[7m4iJf
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publicObject get(finalClass entity, /dIiFr"e}G
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finalSerializable id){ n']@Spm
return getHibernateTemplate().get ,+XQ!y%
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(entity, id); 1'h?qv^(
} `eA 0Z:`g!
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publicList findAll(finalClass entity){ &}WSfZ0{
return getHibernateTemplate().find("from *ood3M[M^
vg<_U&N=-r
" + entity.getName()); qzq>C"z\Y$
} u >x2
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publicList findByNamedQuery(finalString 3.soCyxmc
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namedQuery){ :t(}h!7
return getHibernateTemplate 'O
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().findByNamedQuery(namedQuery); :E.mU{
} *fl1
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publicList findByNamedQuery(finalString query, {Tx+m;5F
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finalObject parameter){ l-5-Tf&j
return getHibernateTemplate |(Sqd;#v
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().findByNamedQuery(query, parameter); |
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} O*CKyW_$t
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publicList findByNamedQuery(finalString query, `":< ]lj
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finalObject[] parameters){ v6]lH9c{,
return getHibernateTemplate V /|@
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().findByNamedQuery(query, parameters); nfd^'}$]
} Hc}(+wQN%
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publicList find(finalString query){ |3s-BKbN4
return getHibernateTemplate().find GZ9XG">
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(query); 'M&`l%dIPf
} ?=aQG0
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publicList find(finalString query, finalObject U<Ag=vsZE
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parameter){ \SyfEcSf2v
return getHibernateTemplate().find nlh%O@,
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(query, parameter); oA`Ncu5
} pj'Yv
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public PaginationSupport findPageByCriteria [<6ez;2q'
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(final DetachedCriteria detachedCriteria){ ~zi&u46
return findPageByCriteria w<>B4m\
Xq9%{'9
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ktnsq&qNL
} 1_%3cN.
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public PaginationSupport findPageByCriteria @qI^xs=Z
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(final DetachedCriteria detachedCriteria, finalint J-b
Z`)[Q
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startIndex){ }{HlY?S
return findPageByCriteria e_7a9:2e
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(detachedCriteria, PaginationSupport.PAGESIZE, ``U>9S"p)
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startIndex); ge*f<#|0U-
}
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public PaginationSupport findPageByCriteria !M\8k$#"n
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(final DetachedCriteria detachedCriteria, finalint p%8y!^g
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pageSize, V4iN2
finalint startIndex){ WUZusW5s
return(PaginationSupport) bDRl}^aO6
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getHibernateTemplate().execute(new HibernateCallback(){ J&2cf#
publicObject doInHibernate p v%`aQ]o{
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(Session session)throws HibernateException { <t\!g
Criteria criteria = K '7M\:zy
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detachedCriteria.getExecutableCriteria(session); B/AS|i] sM
int totalCount = Dy
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((Integer) criteria.setProjection(Projections.rowCount _I+QInD ;)
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()).uniqueResult()).intValue(); ?`lIsd
criteria.setProjection xbsp[0I,
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(null); XC%u`UG
List items = "KSzn
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criteria.setFirstResult(startIndex).setMaxResults M:rE^El
&( aw
(pageSize).list(); /{|JQ'gqX
PaginationSupport ps = ZuH@qq\
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new PaginationSupport(items, totalCount, pageSize, IZn|1X?}\s
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startIndex); 7a\at)q/y
return ps; ,Y ./9F
} [2ez" 4e
}, true); \2#7B8
} RR
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public List findAllByCriteria(final [`2V!rU
hR(\ %p
DetachedCriteria detachedCriteria){ =*>ri
return(List) getHibernateTemplate )G
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().execute(new HibernateCallback(){ +~Wg@
publicObject doInHibernate m - ]E|
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(Session session)throws HibernateException { n.F^9j+V
Criteria criteria = K+|G9
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detachedCriteria.getExecutableCriteria(session); Nz1u:D]
return criteria.list(); =jz [}5
} )jm!bR`
}, true); N.(wR
} -Ph"#R&
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public int getCountByCriteria(final OXDEU.
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DetachedCriteria detachedCriteria){ r^zra|]
Integer count = (Integer) %1h%#/#[
{ 0?^ $R8j
getHibernateTemplate().execute(new HibernateCallback(){ \3q Z0
publicObject doInHibernate a!guZUg6
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(Session session)throws HibernateException { &Zy%Zz
Criteria criteria = rJtpTV@.
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detachedCriteria.getExecutableCriteria(session); #7v=#Jco
return Qv1<)&Ft<
pm` f?Py
criteria.setProjection(Projections.rowCount qg1tDN`s
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()).uniqueResult(); D qu?mg;L
} ;T hn C>U
}, true); `]F}O \H
return count.intValue(); M,w5F5
} $/J4?Wik
} f0M5^
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用户在web层构造查询条件detachedCriteria,和可选的 L
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 F,}7rhY(U^
<]Btx;}
PaginationSupport的实例ps。 B}fd#dr
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ps.getItems()得到已分页好的结果集 '/2)I8
ps.getIndexes()得到分页索引的数组 z#HNJAQ#|
ps.getTotalCount()得到总结果数 aO&!Y\=@
ps.getStartIndex()当前分页索引 mlLx!5h=
ps.getNextIndex()下一页索引 Mh"iyDGA
ps.getPreviousIndex()上一页索引 <H,E1kGw9
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l3N '@GO
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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 Rt.2]eZEJ
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一下代码重构了。 \)M
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我把原本我的做法也提供出来供大家讨论吧: ?G>E[!8ev
;q?WU>c{?
首先,为了实现分页查询,我封装了一个Page类: F]GX;<`
java代码: Ve\.7s
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/*Created on 2005-4-14*/ dnzZ\t>U
package org.flyware.util.page; TUN6`/"
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/** R+# g_"1@p
* @author Joa +!/pzoWpE
* BD2Gv)?g
*/ JD)wxoeg
publicclass Page { @Zzg^1Ilpu
"Wg5eML0
/** imply if the page has previous page */ -&h<t/U
privateboolean hasPrePage; /lLG|aAe
&SMM<^P.
/** imply if the page has next page */ $Zn>W@\
privateboolean hasNextPage; :Qu.CvYF
oM!zeJNA
/** the number of every page */ Bo4iX,zu
privateint everyPage; /u~L3Cp(
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/** the total page number */ ?$@E}t8g\
privateint totalPage; |Hv8GT
t vp kc;
/** the number of current page */ 8vx#QU8E/
privateint currentPage; xf3;:soC
jwp?eL!7
/** the begin index of the records by the current Bq~?!~\?.
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query */ awgS5We|
privateint beginIndex; _iH:>2p 5R
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/** The default constructor */ | MXRNA~
public Page(){ UYH&x:WEd
wV q4DE
} Y z],["*Q
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/** construct the page by everyPage xJ^pqb
* @param everyPage %'MR;hQsd8
* */ .*Axr\x3
public Page(int everyPage){ wKE}BO >
this.everyPage = everyPage; W]5sqtF;6
} [Qn=y/._r
r)gtx!bx
/** The whole constructor */ uA%cie
public Page(boolean hasPrePage, boolean hasNextPage, 08z?i
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int everyPage, int totalPage, }g"K\x:Z
int currentPage, int beginIndex){ G(hzW%P
this.hasPrePage = hasPrePage; (,['6k<
this.hasNextPage = hasNextPage; b?:SCUI
this.everyPage = everyPage; FTh/1"a
this.totalPage = totalPage; /t04}+,e^
this.currentPage = currentPage; l(3\ekU!
this.beginIndex = beginIndex; Mb+CtI_'
} ]Z>zf]<
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/** ui&^ m,
* @return ]g]~!":
* Returns the beginIndex. A}CpyRVCn
*/ U=N]XwjVK<
publicint getBeginIndex(){ sDS0cc6e
return beginIndex; sf,9Ym
} pW5PF)([
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/** 6AKT-r.
* @param beginIndex iI@(Bl]
* The beginIndex to set. TnLblkX
*/ 0E`6g6xMS
publicvoid setBeginIndex(int beginIndex){ GD<pqm`vVY
this.beginIndex = beginIndex; h5ZxxtGU
} @l?2",
g?9%_&/})A
/** JT*Pm"}
* @return ~!ICBF~j
* Returns the currentPage. S^ JUQx7
*/ +zzS
publicint getCurrentPage(){ wi S8S{K5
return currentPage; [KsVI.gn
} J:2Su1"ODh
nEh^{6
/** baib_-$
* @param currentPage Iq(;?_
* The currentPage to set. o[>p
*/ y0
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publicvoid setCurrentPage(int currentPage){ (^= Hq'D
this.currentPage = currentPage; (Ek=0;Cr
} @v=A)L
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/** 3L%g2`
* @return Eq'oy~.oV
* Returns the everyPage. !Nno@SP@
*/ hP=z<&zb/
publicint getEveryPage(){ (N$$N:ac[t
return everyPage; G9jlpf5>
} -0:B2B
hionR)R4
/** Xj;5i
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* @param everyPage Ge4tc
* The everyPage to set.
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*/ cP[]\r+Kj
publicvoid setEveryPage(int everyPage){ }$1Aw%p^
this.everyPage = everyPage; Gq^#.o]
} ai~JY[
!GBGC|avE
/** 8A|i$#.&
* @return Mta;6<
* Returns the hasNextPage. ]@7]mu:oL
*/ eZ
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publicboolean getHasNextPage(){ K7$Vl"l
return hasNextPage; !FR1yO'd>
} me/ae{
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/** Nx"v|"
* @param hasNextPage JulxFjC
* The hasNextPage to set. 1@A*Jj[R%
*/ 4r>buEU
publicvoid setHasNextPage(boolean hasNextPage){ ?u8vK<2h
this.hasNextPage = hasNextPage; m&Lc."
} kn|z
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/** M)!:o/!c S
* @return s\i.pd:Q
* Returns the hasPrePage. Ue0Q| h
*/ k0R;1lZ0n
publicboolean getHasPrePage(){ @DYkWivLu
return hasPrePage; m1lfC
} YP vg(T
Y&_1U/}h
/** 9=Rj9%
* @param hasPrePage h\^> s$
* The hasPrePage to set. JPT VZ
*/ AAt<{
publicvoid setHasPrePage(boolean hasPrePage){ ld*RL:G
this.hasPrePage = hasPrePage; Kq`"}&0b\
} !T3Esv
g_w4}!|
/** s%~p?_P
* @return Returns the totalPage. MF^I] 7_
* P=9Zm
*/ 5-pz/%,
publicint getTotalPage(){ B.J4}Ua
return totalPage; >}ozEX6c2
} {bvm83{T
$W;IW$
/** `g iCytv
* @param totalPage 4c=oAL
* The totalPage to set. y3!=0uPf
*/ DqHVc)9
publicvoid setTotalPage(int totalPage){ ^y"$k
this.totalPage = totalPage; =7`0hS<@F
} 7a:mZ[Vh
;{~F7:i
} '3@WF2a
;zO(bj>
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'2%/h4jY
=}~hbPJM
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 kM?p >V6
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个PageUtil,负责对Page对象进行构造: &xqr&(o
java代码: 8_tMiIE-pS
s/K}]F
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/*Created on 2005-4-14*/ X+K$y:UZ
package org.flyware.util.page; Tl3{)(ezx
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import org.apache.commons.logging.Log; 0Fh*8a}?b
import org.apache.commons.logging.LogFactory; 5!*5mtI
z,oqYU\:
/** ?%h JZm;
* @author Joa g~@0p7]Y
* {P#&e>)v{
*/ RfB""b8]=
publicclass PageUtil { =#<hT
s
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privatestaticfinal Log logger = LogFactory.getLog _ QM
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(PageUtil.class); Ga%]$4u
"/?*F\5
/** Mf&W<n^j
* Use the origin page to create a new page <8At= U
* @param page v; ;X2 a1k
* @param totalRecords puv*p%E
* @return ^F~e?^s
*/ v|Tg %
publicstatic Page createPage(Page page, int UG>OL2m>5
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totalRecords){ q$`:/ ehw
return createPage(page.getEveryPage(), LxVd7r VY6
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/
page.getCurrentPage(), totalRecords); u
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} O`dob&C
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/** zux+ooU
* the basic page utils not including exception j78xMGKO
GD'C^\EaZ
handler .VmI4V?}h
* @param everyPage ZjEO$ts=@
* @param currentPage 5
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* @param totalRecords B<[;rk
* @return page xM;gF2
*/ asW1GZO
publicstatic Page createPage(int everyPage, int FV$= l
%
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currentPage, int totalRecords){ @6$r|:]G-
everyPage = getEveryPage(everyPage); $#@4i4TN-
currentPage = getCurrentPage(currentPage);
9MLvHrB;
int beginIndex = getBeginIndex(everyPage, ;?2vW8{p<
AEnS_Q
currentPage); }]zmp/;a
int totalPage = getTotalPage(everyPage, GGF;T&DWad
{zUc*9
totalRecords); H]=3^ g64
boolean hasNextPage = hasNextPage(currentPage, Xx|&%b{{r
dtM@iDljj
totalPage); #G.3a]p}"
boolean hasPrePage = hasPrePage(currentPage); 2a=WT`xf?
7Nwi\#o
returnnew Page(hasPrePage, hasNextPage, >W'SG3Hmc
everyPage, totalPage, 2c%}p0<;|?
currentPage, ,0 &lag
XU9=@y+|v
beginIndex); ^MJGY,r6b
} hCT%1R}rKr
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privatestaticint getEveryPage(int everyPage){ -t6d`p;dR
return everyPage == 0 ? 10 : everyPage; /"CKVQ
} HxY,R^
BQS9q'u_
privatestaticint getCurrentPage(int currentPage){ .4!N#'
return currentPage == 0 ? 1 : currentPage; N`Bt|#R
} a
LmVOL{
?3}UO:B
privatestaticint getBeginIndex(int everyPage, int c(#`z!FB
<YeF?$S}
currentPage){ G<jpJ
return(currentPage - 1) * everyPage; U-FA^c;
} 6@XutciK
Xp} vJl
privatestaticint getTotalPage(int everyPage, int DQlaSk4hF_
b7AuKY{L
totalRecords){ RaU.yCYyu
int totalPage = 0; dWqFP
4(aesZ8h
if(totalRecords % everyPage == 0) 7-o=E=
totalPage = totalRecords / everyPage; \aZ(@eF@@Q
else 0= 'DDy
totalPage = totalRecords / everyPage + 1 ; Ab2g),;c
CY>NU
return totalPage; rIb[gm)Rk
} (FjgnsW
Ve8!
privatestaticboolean hasPrePage(int currentPage){ ==XP}w)m
return currentPage == 1 ? false : true; 9)l_(*F
} y9*H
!7xp<=
privatestaticboolean hasNextPage(int currentPage, CMBW]b|
<go~WpA|r
int totalPage){ qz0v1057#
return currentPage == totalPage || totalPage == 4[J3HLQ
z}Z`kq+C
0 ? false : true; 7lVIN&.=
} #Y5I_:k
F7;xf{n<
S-rqrbr|AT
} tJwF
h6
g?>AY2f[5
/5x`TT
T),:8/
huF L [
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。 ,g,jY]o
@zJI0_Bp
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 BL8\p_U
5./
(fgx>
做法如下: -ufmpq.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 N6J$z\
P
sN
C?o[9l!
的信息,和一个结果集List: hL`zV
java代码: uf;q/Wr
Vd?v"2S(9
'!.;(Jo
/*Created on 2005-6-13*/ q~^:S~q
package com.adt.bo;
yX-xVvlv@
s^oNQ}
import java.util.List; \9}5}X_x.
@qC:% |>
import org.flyware.util.page.Page; c"YK+2
0&.lSwa
/** q9
;\B&
* @author Joa b;t]k9:"L
*/ -Y[-t;
publicclass Result { t~M<j|]k
y[|g!9Rp
private Page page; =+"'=o
<=inogf
private List content; o 4b{>x
KB"iF}\P0
/** $0*47+f
* The default constructor MzG ryM-
*/ &!a2%%1#N
public Result(){ f
oVD+\~Y
super(); m4DH90~a8
} 5HbTgNI
q8h{-^"
/** Qwa"AY5pW
* The constructor using fields ?8, N4T0)
* +wUhB\F
*
* @param page Dgm%Ng
* @param content 84!4Vz^
*/ SNU
bY6
public Result(Page page, List content){ AY;+Ws
this.page = page; v 2 GhR*
this.content = content; O<h#|g1
} `az`?`i7
cA%U
/** Zd(d]M_x
* @return Returns the content. ^d9raYE`'
*/ gk z#kiGF
publicList getContent(){ LgNNtZ&F
return content; 0X?fDz}jd
} B<XPu=|
3b3cNYP
/** E)hinH
* @return Returns the page. +=h!?<*C8
*/ >Y'yM4e*
public Page getPage(){ jp^WsHI3
return page; FqsjuU@l
} J3x7i8
na3kHx@
/** D&r8V;G[[
* @param content 8-5jr_*
* The content to set. mG~y8nUtp
*/ SU'1#$69F
public void setContent(List content){ m[{&xF|_
this.content = content; DP_Pqn8p&M
} iFCH$!
I|IlFu?O=
/** (A'q@-XQ
* @param page <e&QTyb
* The page to set. aTh%oBrtP
*/ s~$4bN>LD
publicvoid setPage(Page page){ k6-n.Rl01
this.page = page; mF}k}0
} Zax]i,Bx
} -b)zira
,:(leWeA9
*wB-lg7%
NoAb}1uae
MJ9SsC1
2. 编写业务逻辑接口,并实现它(UserManager, jN}7BbX
ePpK+E[0Z
UserManagerImpl) ~9 WJrRWB
java代码: 3t8H?B12ow
/Z "
4[
/C"s_:m;3
/*Created on 2005-7-15*/ fF>qU-
package com.adt.service; YaZt+WA
I!7.fuO
import net.sf.hibernate.HibernateException; W:poUG1UR
/e sk
import org.flyware.util.page.Page; m=.7f9
OEE{JVeI
import com.adt.bo.Result; `VFl|o#H
ZU.)K>'
/** :ZfUjqRE
* @author Joa f5b`gvCY,#
*/ pd>a6 lI`
publicinterface UserManager { ~R@m!'Ik
:/[YY?pg-
public Result listUser(Page page)throws :
|*,Lwvd
KHus/ M&0
HibernateException; @*"<U]
/-YlC(kL
} /N]Ow
oZ>`Qu
sR>;h /
4`-?r%$,:
31sgf5 s
java代码: V=4u7!ha
;k&k#>L!K
#Wm@&|U
/*Created on 2005-7-15*/ b)hOzx
package com.adt.service.impl; HA.NZkq.tV
EOnp!]Y
import java.util.List; ]6%%X+$7
Q xF8=p
import net.sf.hibernate.HibernateException; `?o1cf A
qv*uM0G6i
import org.flyware.util.page.Page; 4fu\3A&
import org.flyware.util.page.PageUtil; ~sHZh
1xdESorX(
import com.adt.bo.Result; Cb%.C;q
import com.adt.dao.UserDAO; 'oiD#\t4
import com.adt.exception.ObjectNotFoundException; h,'mN\6t
import com.adt.service.UserManager; <#p|z`N
=Sb:<q+Q
/** 3@ F+ E\k
* @author Joa tD~PvUJ
*/ 0o=6A<#x
publicclass UserManagerImpl implements UserManager { jdg
~!<C
p]V-<
private UserDAO userDAO; [mB(GL
'q};L 6
/** n#^?X
* @param userDAO The userDAO to set. /romTK4
*/ p[@oF5M
publicvoid setUserDAO(UserDAO userDAO){ 22Y!u00D
this.userDAO = userDAO; ^0-e,d
9h
} (:y,CsR}4
W]!@Zlal
/* (non-Javadoc) 'e<HP Ni)
* @see com.adt.service.UserManager#listUser [zh4W*K_cq
cJHABdK-
(org.flyware.util.page.Page) x^#6>oOR
*/ *t?~)o7
public Result listUser(Page page)throws @O<@f8-
}[KDE{,V
HibernateException, ObjectNotFoundException { Qw6KX#n
int totalRecords = userDAO.getUserCount(); T[4[/n>i
if(totalRecords == 0) ~D-JZx
throw new ObjectNotFoundException -l P )
RI5g+Du?
("userNotExist"); nqurY62Ip
page = PageUtil.createPage(page, totalRecords); u>t|X}JH
List users = userDAO.getUserByPage(page); hs{&G^!jo
returnnew Result(page, users); da9*9yN
} ebO`A2V'(
:tjgg]
} ]{Mci]H6T
_UH/}!nqB
2|0Qk&
G. -h=DT]
T1Gp$l
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 GCP{Z]u
[xZ/ZWb/
询,接下来编写UserDAO的代码: y~==waZw
3. UserDAO 和 UserDAOImpl: 2,8/Cb
java代码: *l> [`U+
;T5,T
6Q.{llO
/*Created on 2005-7-15*/ wO2V%v^bp
package com.adt.dao; |<j,Tr1[
!"`@sd~
import java.util.List; -~vl+L
RjR&D?dc
import org.flyware.util.page.Page; %k3NT~
,>bGbx
import net.sf.hibernate.HibernateException; [)Z'N/;0
'!j #X_;
/** .%x"t>]
* @author Joa ?qd,>
*/ i\kTm?BQZ
publicinterface UserDAO extends BaseDAO { QMXD9H0{
O8K@&V p
publicList getUserByName(String name)throws wMH[QYb<*
05l0B5'p
HibernateException; c N02roQl
] ?DDCew
publicint getUserCount()throws HibernateException; Q(~3pt
3W7;f!
publicList getUserByPage(Page page)throws krQl^~@
M>*0r<qn
HibernateException; E^Q@9C<!d
j!zA+hF(
} g,t3OnxS?
Veb+^&
Lv
`#zgo_f
2-vJv+-
~t'#n V
java代码: $$haVY&
zAeGkP ~K
9">zdFC'
/*Created on 2005-7-15*/ ioB|*D<U2
package com.adt.dao.impl; q[{:
d&}pgb-Md
import java.util.List; =y)p>3p}&
F^ I\X
import org.flyware.util.page.Page; $q Zc!Qc
^=eq .(>
import net.sf.hibernate.HibernateException; LYd}w(}
import net.sf.hibernate.Query; Q)x?B]b-
w{k1Y+1
import com.adt.dao.UserDAO; 1a7!4)\
Ad dGB^7yl
/** :y=!{J<
* @author Joa k_,MoDz
*/ 5h_<R!jA
public class UserDAOImpl extends BaseDAOHibernateImpl !UBy%DN~k
cvZni#o2)
implements UserDAO { ?j1_
n,d
a$w},=
`E
/* (non-Javadoc) VK @$JwdL
* @see com.adt.dao.UserDAO#getUserByName U8CWz!;Qz
6BDt.bG
(java.lang.String) +68+PhHF
*/ 2{Wo-B,wt~
publicList getUserByName(String name)throws W[@i;f^g
z7-`Y9Ypd
HibernateException { +O)]^"TG
String querySentence = "FROM user in class :=rA Yc3]
FJO"|||Y'|
com.adt.po.User WHERE user.name=:name"; r8IX/ ,
Query query = getSession().createQuery oS~}TR:}
C@*%AY
(querySentence); ` *>V6B3
query.setParameter("name", name); %oAL
return query.list(); g(mxhD!k
} D`~JbKV5@^
d!`lsh@tF
/* (non-Javadoc) ~_'0]P\
* @see com.adt.dao.UserDAO#getUserCount() Y.q>EUSH
*/ o[o:A|n
publicint getUserCount()throws HibernateException { >R( 8/#|E
int count = 0; \M7I&~V
String querySentence = "SELECT count(*) FROM {I`B[,*
Xc\*9XV:
user in class com.adt.po.User"; kt:)W])V
Query query = getSession().createQuery plK=D#)
+AB6lv
(querySentence); rFhW^fP/
count = ((Integer)query.iterate().next 3AK(dC[ri
?$3r5sx
()).intValue(); =K .r
return count; N6h1|_o
} 6MuWlCKF8
(YIhTSL"]
/* (non-Javadoc) Z)/6??/R
* @see com.adt.dao.UserDAO#getUserByPage Kaf>
\@i=)dA
(org.flyware.util.page.Page) =K:(&6f<t
*/ \ZS\i4
publicList getUserByPage(Page page)throws w TlGJ$D0
sYI~dU2H
HibernateException { QjLji+L
String querySentence = "FROM user in class p"KU7-BfvC
,E&Bn8L~O
com.adt.po.User"; u,fA!
Query query = getSession().createQuery prZ55MS.
#Rc5c+/(
(querySentence); So#dJ>
query.setFirstResult(page.getBeginIndex()) iSlFRv?a
.setMaxResults(page.getEveryPage()); o
w2$o\hC
return query.list(); =HMmrmz:
} R aefj(^V
1 o|T
} X:_<Y_JT
N<(HPE};
/KAlK5<
8zZSp
^;zWWg/d
至此,一个完整的分页程序完成。前台的只需要调用 6^sHgYR
e&2wdH&
userManager.listUser(page)即可得到一个Page对象和结果集对象 J/t!-!
4b4QbJ$
的综合体,而传入的参数page对象则可以由前台传入,如果用 aM$\#Cx
eaQ90B4
webwork,甚至可以直接在配置文件中指定。 f/ajejYo?,
AliRpxxd
下面给出一个webwork调用示例: k,rWa
java代码: FSU<Y1|XM
H>.B99vp
>dk9f}7-
/*Created on 2005-6-17*/ ('t kZt%8
package com.adt.action.user; >!}`%pk(
-u|l}}bh
import java.util.List; -l
"U"U"F
0 O~p7D
import org.apache.commons.logging.Log; 5@ foxI
import org.apache.commons.logging.LogFactory; :M j_2
import org.flyware.util.page.Page; kM!V.e[g
?>V6P_r>
import com.adt.bo.Result; B;!f<"a8
import com.adt.service.UserService; +yWR#[`n
import com.opensymphony.xwork.Action; RZO5=L9E
6Nt$ZYS
/** (;}tf~~r
* @author Joa TFy7HX\Oq
*/ F6W}mMZH/N
publicclass ListUser implementsAction{ Pd~MiyO;K
2zK"*7b?
privatestaticfinal Log logger = LogFactory.getLog &x0C4Kh
f7J,&<<5w
(ListUser.class); iITp**l
YsP/p-
private UserService userService; !8*McOI
JDv-O&]
private Page page; ?+r!z
$b>}C= gt
privateList users; -#?<05/C>
qzK("d
/* xQu
eE{
* (non-Javadoc) /APcL5:=
* wGJjA=C
* @see com.opensymphony.xwork.Action#execute() knT.l"
*/ m&IsDAn
publicString execute()throwsException{ ]` ]g@v
Result result = userService.listUser(page); =Ikg.jYq&F
page = result.getPage(); kq-6HDR
users = result.getContent(); e"Rm_t
return SUCCESS; DA"}A`HfI
} @T&t.|`
-[R!O'N9
/** =MLf[
* @return Returns the page. XoR>H4xh
*/ \k@Z7+&7
public Page getPage(){ dB;3.<S=
return page; "&lN\&:
} )ofm_R'q*
\M(*=5
/** ;;V\"7q'
* @return Returns the users. (9$"#o
*/ 0mexF@
publicList getUsers(){ '{f=hE_/
return users; S#8>ZwQ
} F9H~k"_ZJR
(][LQ6Pc
/** d~*TIN8Ke~
* @param page {8@\Ij
* The page to set. V5"HwN+`
*/ dqe7s Zl!
publicvoid setPage(Page page){ X=~V6m
this.page = page; Ct]A%=cZW
} ?a.+j8pbGg
ZA\/{Fw
/** KJh,,xI>by
* @param users mm[SBiFO\
* The users to set. otr>3a*'
*/ B@t'U=@7
publicvoid setUsers(List users){ "tu*YNP\Q
this.users = users; 5Qa
zHlJ
} :0^s0l
5j^NV&/_
/** C3VLV&wF
* @param userService }/e`v6
* The userService to set. N4UM82N
*/ 9z ?7{2C
publicvoid setUserService(UserService userService){ eW8[I'v_&
this.userService = userService; #[ -\lU|
} @5<CXTdF9c
} *t9eZ!_f?
[!"XcFY:a
%<Q*Jf
27 GhE
cA;js;x@
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, KhaYr)&~
o-eKAkh
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 ^_>!B)
orIQ~pF#
么只需要: jo98
jA<
java代码: \u{8Bak0
qpqokK
\#dl6:"
<?xml version="1.0"?> Q M1F?F
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork F#V q#|_)>
p-$Cs _{Z
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \ijMw
u oVNK
1.0.dtd"> Qv#]81i(1
eN-au/kN
<xwork> BC/_:n8O
3Wx,oq;4-
<package name="user" extends="webwork- WZFH@I28
1BTIJ G w
interceptors"> 9dKul,c
7#2j>G{?]v
<!-- The default interceptor stack name >nnY:7m
KMjg;!y
-->
Xm_$
dZ
<default-interceptor-ref smU4jh9S
$v27]"]
name="myDefaultWebStack"/> 0 bSA_
cF+ X,]=6
<action name="listUser" '$m7ft}
8 i0
class="com.adt.action.user.ListUser"> hW2.8f$
<param &M"ouy Zo9
py<_HyJ
name="page.everyPage">10</param> \2X$C#8E
<result F 3RB
s&
yk
name="success">/user/user_list.jsp</result> =mt?Cn}
</action> Utt>H@t[
E{Vo'!LY
</package> n9hm790x-
KCR N}`^
</xwork> <$E6oZ
faJM^ u
kE)!<1yy2
RtV.d\
FY#!N
L
=@r--E
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 qfL-r,XS`F
d*]Ew=^L
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。 BBL485`
pGWA\}'
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 N{joXHCu
.;I29yk\XS
;;&F1@3tBa
y?z\L
\0*l,i1&
我写的一个用于分页的类,用了泛型了,hoho L-h$Z0]_F
oXY Moi
java代码:
6rDfQ`f\p
6Wf^0ok
zV.pol
package com.intokr.util; .p@N:)W6
<,8l *1C
import java.util.List; 2qj{n+
V[hK2rVH.
/** VcgBLkIF
* 用于分页的类<br> m *X7T
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -l*g~7|j
* ae`|ic
* @version 0.01 UQ8bN I7
* @author cheng ?&c:q3_-Z
*/ 1;r69e
public class Paginator<E> { #MgvG,
privateint count = 0; // 总记录数 k DsIp=
privateint p = 1; // 页编号 f}fsoDoQ=
privateint num = 20; // 每页的记录数 zQ8!rCkg4
privateList<E> results = null; // 结果 S`q%ypy
" 'tRfB
/** UH3t(o7O
* 结果总数 _a'A~JY
*/ 9y] J/1#
publicint getCount(){ =xl~][
return count; d>i13dAI
} Z`_.x
&Y
h'5Cp(G
publicvoid setCount(int count){ %FA@)?~
this.count = count; t9
F=^)s
} BGWAh2w6
n9UKcN-
/** z@h~Vb&I
* 本结果所在的页码,从1开始 s3 QEi^~
* "^rNr_
* @return Returns the pageNo. O6c\KFBSJ
*/ :,UN8L "
publicint getP(){ sa#.l% #
return p; #@//7Bf%
} ~L?nq@DL
n^9 ?~
/** )|]dmQ-
* if(p<=0) p=1 &7 [[h+Lb
* =nRuY'
* @param p Q< *8<Oo4g
*/ ?p^2Z6J'$
publicvoid setP(int p){ 8tc*.H{^+
if(p <= 0) %'ZN`XftG
p = 1; < o I8-f
this.p = p; AXW!]=?X
} n Wgv~{,x
]7/gJ>g,
/** P]6}\
]~
* 每页记录数量 o$J6 ~dn
*/ RUXCq`)"<
publicint getNum(){ +x1/-J8_sg
return num; 0|Ucd
} $99R| ^
!1:@8q
/** w]!0<
* if(num<1) num=1 R}{GwbF_\
*/ 0i@:KYP
publicvoid setNum(int num){ ><Z'D
if(num < 1) %xlpB75N4N
num = 1; 1y[B[\
this.num = num; Ijo(^v@
} Yp5L+~J[
=3'(A14C=
/** Pl
* 获得总页数 SkP[|g'56
*/ j%tEZ"H
publicint getPageNum(){ JF9Hfs/jS
return(count - 1) / num + 1; e!0OW7kV
} a6nlt?1?D
5Pke8K
/** 32>x^>G=>
* 获得本页的开始编号,为 (p-1)*num+1 _l&ucA
*/ la,
h
publicint getStart(){ 9([6d.`~
return(p - 1) * num + 1; nX[;^v/
} ZKdh%8C
N}QFGX
/** (B#(Z=
* @return Returns the results. C0m\SNR
*/ S/Oxr%H
publicList<E> getResults(){ \<65??P
return results; H5M#q6`H6
} 3H8Al
#A<"4#}
public void setResults(List<E> results){ /lH'hcXcX
this.results = results; pj|X]4?wdI
} ;}4k{{K
L;)v&a7[P
public String toString(){
WL-0(
StringBuilder buff = new StringBuilder GU6qIz|
;Bs^iL
(); {bkGYx5.C
buff.append("{"); X;EJ&g/
buff.append("count:").append(count); |]ucHV
buff.append(",p:").append(p); )f*Iomp]@
buff.append(",nump:").append(num); }76.6=~
buff.append(",results:").append kk_zVrQ<
,wK 1=7
(results); zSgjp\
buff.append("}"); LDQ
e^
return buff.toString(); \Jpw1,6
} fusPMf *[
W"qL-KW
} O
E|+R4M
KH}t:m+h
uPDaq ]A