Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 5d4-95['_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $9J"r9@@
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 H{GbOI.
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 9Pb0Olh
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分页支持类: oL6_Ya
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java代码: )US)-\^
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package com.javaeye.common.util; gh
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import java.util.List; [}AcCXg`L
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publicclass PaginationSupport { |F=^Cu,
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publicfinalstaticint PAGESIZE = 30; W4| ;JmT.r
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privateint pageSize = PAGESIZE; &`%C'KZ
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privateList items; Z2 @&4_P
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privateint totalCount; kB:R-St
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privateint[] indexes = newint[0]; IWQ8e$N
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privateint startIndex = 0; JL$RBr
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public PaginationSupport(List items, int M>^IQ
;}PL/L$L6;
totalCount){ N,1wfOE
setPageSize(PAGESIZE); TUUBC%
setTotalCount(totalCount); 3whyIXs
setItems(items); FPMW"~v
setStartIndex(0); fGfv{4R
} P"#^i<ut@T
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public PaginationSupport(List items, int C^~iz
in
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totalCount, int startIndex){ `<Ftn
setPageSize(PAGESIZE); K4tX4U[Z
setTotalCount(totalCount); >ylVES/V
setItems(items); >9klh-f
setStartIndex(startIndex); = G_6D
} j?,$*Fi
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public PaginationSupport(List items, int mU_O64
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totalCount, int pageSize, int startIndex){ xphqgOc12,
setPageSize(pageSize); qnlj~]NV
setTotalCount(totalCount); ])JJ`Z8Bk
setItems(items); n-Xj>
setStartIndex(startIndex); =sm(Z;"
} YUH/tl
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publicList getItems(){ oa4}GNH
return items; 'SY&-<t(
} 3_ >R's8P
}0TY
publicvoid setItems(List items){ ,)RdXgCs
this.items = items; 'K!kJ9oqe
} )>/c/B
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publicint getPageSize(){ G1l(
return pageSize; GB=q}@&8p
} e'`oisJU?q
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publicvoid setPageSize(int pageSize){ QJ/SP
this.pageSize = pageSize; #.@=xhK/
} bODl
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publicint getTotalCount(){ y{N9.H2
return totalCount; p%s
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} JjmL6(*ui
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publicvoid setTotalCount(int totalCount){ YJy*OS_&
if(totalCount > 0){ w9FI*30
this.totalCount = totalCount; 3%} Ma,
int count = totalCount / cm]]9z_<
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pageSize; oxzNV&D[{`
if(totalCount % pageSize > 0) bm4W,
count++; 1mX*0>
indexes = newint[count]; 1 W0; YcT]
for(int i = 0; i < count; i++){ x6t;=
indexes = pageSize * |^F-.Z
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i; qkIU>b,B
} $o/>wgQY-
}else{ o;[oy#aWl_
this.totalCount = 0; &0g,Xkr
} g|P hNo
} 1@WGbORc*
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publicint[] getIndexes(){ Y8PT`7gd`
return indexes; R+K[/AA
} #RF=a7&F
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publicvoid setIndexes(int[] indexes){ #jX>FXo
this.indexes = indexes; xYT.J 6
} &Yg/08*
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publicint getStartIndex(){ AV p[gr
return startIndex; wLtTC4D
} H[D/Sz5`
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publicvoid setStartIndex(int startIndex){ x}{VHp`|ld
if(totalCount <= 0) h,x]
this.startIndex = 0; Al|7Y/
elseif(startIndex >= totalCount) ca=e_sg
this.startIndex = indexes gNwXOd u
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[indexes.length - 1]; V%ch'
elseif(startIndex < 0) =lwS\mNs
this.startIndex = 0; Bu1z$#AC
else{ #lF<="y%X
this.startIndex = indexes K(gj6SrjV
*3$,f>W^
[startIndex / pageSize]; HhvG#Sam!
} ^aXBt
} X2cR+Ha0
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publicint getNextIndex(){ h6*`V
int nextIndex = getStartIndex() + rg,63r
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pageSize; ]D%k)<YK
if(nextIndex >= totalCount) {n]sRz
return getStartIndex(); H#inr^Xa
else E: GJ$I
return nextIndex; S F>D:$a
} .jp]S4~
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publicint getPreviousIndex(){ 9$&e~^&B
int previousIndex = getStartIndex() - 6mdnEmFM]
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pageSize; ^{:jY, ?]
if(previousIndex < 0) iIE(zw)H
return0; <^U(ya
else _sVs6AJ
return previousIndex; $]kg_l)
} [.X%:H+
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} KeB4Pae|V
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抽象业务类 sg{D ?zl
java代码: U*Qq5=dqD
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/** M"^Vf{X^
* Created on 2005-7-12 5vft}f
*/ @@83PJFid
package com.javaeye.common.business; pm]DxJ@
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import java.io.Serializable; D a[C'm=
import java.util.List; N@6OQ:,[F
yvCR = C
import org.hibernate.Criteria; Jwd&[
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import org.hibernate.HibernateException; d&uTiH? 0
import org.hibernate.Session; toqzS!&.v
import org.hibernate.criterion.DetachedCriteria; .dT;T%3fO
import org.hibernate.criterion.Projections; OZD!#YI
import R9h>I3F=c
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org.springframework.orm.hibernate3.HibernateCallback; 4q13xX
import c1kxKxE
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org.springframework.orm.hibernate3.support.HibernateDaoS KC:4
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upport; *Ca)RgM
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import com.javaeye.common.util.PaginationSupport; lt6;*z[
j yRSEk$
public abstract class AbstractManager extends =nx:GT3&[
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HibernateDaoSupport { [!@oRK=~
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privateboolean cacheQueries = false; *xg`Kwl5Kl
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privateString queryCacheRegion; S tnv>
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publicvoid setCacheQueries(boolean f&}A!uLe4x
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#*
cacheQueries){ d-;9L56{P
this.cacheQueries = cacheQueries; .l+~)$
} d:hL
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publicvoid setQueryCacheRegion(String `%M-7n9Y
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queryCacheRegion){ ^YR|WK Y
this.queryCacheRegion = oD#>8Aw s
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queryCacheRegion; 6_<s=nTX
} c~UAr k S
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publicvoid save(finalObject entity){ 030U7 VT1
getHibernateTemplate().save(entity); ~sIGI?5f
} [z% ?MIT
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publicvoid persist(finalObject entity){ 6f?BltFaN
getHibernateTemplate().save(entity); 7q!yCU
} tB7K&ssi
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publicvoid update(finalObject entity){ BKQIo)g.G
getHibernateTemplate().update(entity); /Y[o=Uyl
} <s/<b*T
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publicvoid delete(finalObject entity){ (+UmUx=
getHibernateTemplate().delete(entity); ZP6x
} 'Z.OF5|eGT
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publicObject load(finalClass entity, sr+gD*@h
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finalSerializable id){
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return getHibernateTemplate().load 3G%wZ,)C
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(entity, id); V+O0k: o
} G7Z vfLR{:
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publicObject get(finalClass entity, 0aC2 Pym^
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finalSerializable id){ drENkS=,
return getHibernateTemplate().get @1v3-n=
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(entity, id); i)7n c
} o)tKH@`vE
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publicList findAll(finalClass entity){ 1Sg|3T8bGT
return getHibernateTemplate().find("from r+{d!CHq}
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" + entity.getName()); -".kH<SWv
} mA(nyF
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publicList findByNamedQuery(finalString "Su
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namedQuery){ 9DOkQnnc
return getHibernateTemplate UU iNR
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().findByNamedQuery(namedQuery); D[89*@v
} ZT) !8
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publicList findByNamedQuery(finalString query, *$i; o3
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finalObject parameter){ 7q%|4Z-~
return getHibernateTemplate ^^7L"je]g
euV $2Fg
().findByNamedQuery(query, parameter); @s%X
} i}PK$sa#c
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publicList findByNamedQuery(finalString query, J?UA:u
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finalObject[] parameters){ m$fQ `XzU
return getHibernateTemplate 0A#*4ap
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().findByNamedQuery(query, parameters); vG ]GQ#
} 6FL?4>MZ
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publicList find(finalString query){ J| SwQE~
return getHibernateTemplate().find 6OL41g'
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(query); (U|)xA]y!
} XC|*A$x,
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publicList find(finalString query, finalObject F:M>z=
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parameter){ fyM3UA\U
return getHibernateTemplate().find 5>k>L*5J
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(query, parameter); }m6f^fs}
} ?gLR<d_
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public PaginationSupport findPageByCriteria In
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(final DetachedCriteria detachedCriteria){ oW0gU?Rr)u
return findPageByCriteria vO\:vp4fH
,{k<JA{
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~?#~ Ar
} r5o@+"!
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public PaginationSupport findPageByCriteria ,-@xq.D
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(final DetachedCriteria detachedCriteria, finalint 0 _Q*E3
(O$}(Tn
startIndex){ D =$4/D:;
return findPageByCriteria O!;H}{[dg
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(detachedCriteria, PaginationSupport.PAGESIZE, zhNQuK,L
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startIndex); WtIMvk
} }N?g|
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public PaginationSupport findPageByCriteria ?RHn @$g8M
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(final DetachedCriteria detachedCriteria, finalint .>}BNy
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pageSize, (Aorx #z
finalint startIndex){ P{?;T5ap6
return(PaginationSupport) G.E[6G3
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getHibernateTemplate().execute(new HibernateCallback(){ 8qn 9|
publicObject doInHibernate xcst<=
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(Session session)throws HibernateException { KyT uF
Criteria criteria = iHPUmTus--
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gbt
detachedCriteria.getExecutableCriteria(session); `%e|$pK
int totalCount = >?z:2@Q)B
u t$c)_
((Integer) criteria.setProjection(Projections.rowCount j !`B'{cH
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()).uniqueResult()).intValue(); H( vx/q
criteria.setProjection C,fY.CeI
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(null); vm8$:W2 }
List items = !v0"$V5+i
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criteria.setFirstResult(startIndex).setMaxResults (~JwLe@a
A_Rrcsl4
(pageSize).list(); P$_&
PaginationSupport ps = ioxbf6{
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new PaginationSupport(items, totalCount, pageSize, C0QM#"[
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startIndex); 3f"C!l]Xu
return ps; z`4c 4h]I
} jXixVNw
}, true); Fk{J@Y
} ZWS2q4/S
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public List findAllByCriteria(final => qTNh*'
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DetachedCriteria detachedCriteria){ b?8)7.{F{
return(List) getHibernateTemplate -jB3L:
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().execute(new HibernateCallback(){ )hBE11,PB
publicObject doInHibernate {L].T#
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(Session session)throws HibernateException { -}P7$|O&
Criteria criteria = ]W/>Ldv
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detachedCriteria.getExecutableCriteria(session); le8 #Z}p
return criteria.list(); 2Q@Y^t
} y \D=Z
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}, true); 0mTr-`s
} xR?V,uV'$&
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public int getCountByCriteria(final %Ds+GM-
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DetachedCriteria detachedCriteria){ I-kWS4
Integer count = (Integer) 5wv fF.v
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getHibernateTemplate().execute(new HibernateCallback(){ uH:YKH':/
publicObject doInHibernate V%*b@zv
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(Session session)throws HibernateException { 1_hW#I\'
Criteria criteria = cG{L
jt
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detachedCriteria.getExecutableCriteria(session); 'RbQj}@x
return * ?]~
#
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criteria.setProjection(Projections.rowCount iX "C/L|JN
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()).uniqueResult(); 6KRO{QK
} [%pRfjM
}, true); g<wRN#B
return count.intValue(); n<7u>;SJQ
} nS9wb1Zl
} _MuZ4tc
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用户在web层构造查询条件detachedCriteria,和可选的 H
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %\Wf^6Y^
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PaginationSupport的实例ps。 \+ 0k+B4a
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ps.getItems()得到已分页好的结果集 Lja 7
ps.getIndexes()得到分页索引的数组 %JyXbv3m,
ps.getTotalCount()得到总结果数 {<=#*qx[Y!
ps.getStartIndex()当前分页索引 />44]A<
ps.getNextIndex()下一页索引 ,|h)bg7.
ps.getPreviousIndex()上一页索引 2VGg 6%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~}"]&%Q{J
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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 [yS#O\$'e
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一下代码重构了。 (Pbg[AY
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我把原本我的做法也提供出来供大家讨论吧: Qk1xUE
n, i'Dhzk
首先,为了实现分页查询,我封装了一个Page类: 8|%^3O 0X
java代码: 8}s.Fg@tE
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/*Created on 2005-4-14*/ cC'x6\a
package org.flyware.util.page; yR;{
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/** N!2Rl
* @author Joa nh>K`+>co
* Ch \&GzQ
*/ F4L;BjnJ
publicclass Page { \Ae9\Jp8M
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/** imply if the page has previous page */ Z\}K{#
privateboolean hasPrePage; pmWr]G3,*
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/** imply if the page has next page */ CQh,~
privateboolean hasNextPage; Q'O[R+YT ,
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/** the number of every page */ /FP5`:PfL
privateint everyPage; Q[F}r`
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/** the total page number */ rl2&^N
privateint totalPage; :GpDg
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/** the number of current page */ ={>Lrig:l
privateint currentPage; $37
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/** the begin index of the records by the current ,\2:/>2
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query */ rgmF: C
privateint beginIndex; c(;a=n(E#
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/** The default constructor */ N-
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public Page(){ l 'DsZ9y@2
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} A+J*e
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/** construct the page by everyPage 0sca4G0{
* @param everyPage Bw%Qbs0Q
* */ ,<BbpIQ2o
public Page(int everyPage){ *}k;L74|
this.everyPage = everyPage; ^sN (
} yeDsJ/L
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/** The whole constructor */ ivDGZI9
public Page(boolean hasPrePage, boolean hasNextPage, M])dJ9&e
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int everyPage, int totalPage, ,C%eBna4Iq
int currentPage, int beginIndex){ EI!6MC)
this.hasPrePage = hasPrePage; < -W*$?^
this.hasNextPage = hasNextPage; MUfG?r\t
this.everyPage = everyPage; Q'_z<V
this.totalPage = totalPage; tyaA\F57
this.currentPage = currentPage; FFdBtB
this.beginIndex = beginIndex; b4^`DHRu6
} ;q N+^;,2
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/** M@0;B30L
* @return )jrV#/m9
* Returns the beginIndex. 2{|h8oz
*/ L_=3<nE
publicint getBeginIndex(){ 3bnS
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return beginIndex; jReXyRmo({
} GFr|E8
u#}[ZoI
/** 5onm]V]
* @param beginIndex 2^i(gaXUQ
* The beginIndex to set. g1t0l%_7^
*/ ,U(1NK8o
publicvoid setBeginIndex(int beginIndex){ AL>$HB$
this.beginIndex = beginIndex; Jgnhn>dHe
} o sKKt?^?
a!O0,y
/** Q0EiEX)
* @return 8Q_SRwN
* Returns the currentPage. >jD[X5Y
*/ 4Y[1aQ(%
publicint getCurrentPage(){ (}}S9 K
return currentPage; cM&{+el
} E[Cb|E
|4'Y/re
/** y+7w,m2
* @param currentPage BcI|:qv|
* The currentPage to set. zOQ>d|p?X
*/ As>_J=8} 3
publicvoid setCurrentPage(int currentPage){ (<^ yqH?
this.currentPage = currentPage; ;G%R<Z
} yn#X;ja-
lok=
/** =UV`.d2[
* @return _3ZYtmn.
* Returns the everyPage. >$4d7.^hb/
*/ !"Oh36
publicint getEveryPage(){ :0h_K
return everyPage; G37U6PuZi
} h<$MyN4]g
i[ mEi|
/** w K}T`*k
* @param everyPage 6i}iAP|0
* The everyPage to set. Dc,I7F|%
*/ ~ 0M'7q'
publicvoid setEveryPage(int everyPage){ P-9<YN
this.everyPage = everyPage; %$b:X5$Z
} vh$%9ed
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/** <_7*67{
* @return )rC6*eR
* Returns the hasNextPage. r(P(Rj2~
*/ lv04g} W
publicboolean getHasNextPage(){ soQ1X@"0
return hasNextPage;
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} t2)rUWg
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/** ~;N^g4s
* @param hasNextPage ]UmFhBR-
* The hasNextPage to set. sIy^m}02
*/ >6?__v]9G
publicvoid setHasNextPage(boolean hasNextPage){ ,k;^G><
=
this.hasNextPage = hasNextPage; [EKQR>s)
} "yS _s
}"|K(hq
/** ,'u W*kx
* @return h D/*h*}T>
* Returns the hasPrePage. nR-YrR*k
*/ 3xaR@xjS
publicboolean getHasPrePage(){ cH&J{WeZa
return hasPrePage; -[wGX}}
} aJ>65RJ^=
;<ZLcTL
/** S Em Q@1
* @param hasPrePage |AozR ~
* The hasPrePage to set. N(Tz%o4
*/ 2%_vXo=I
publicvoid setHasPrePage(boolean hasPrePage){ WHj'dodS
this.hasPrePage = hasPrePage; tIuCct-
} .?loO3 m
:s7m4!EF
/** M
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* @return Returns the totalPage. c_4[e5z
* ^y<<>Y'I
*/ N u<_}
publicint getTotalPage(){ uc){+'[
return totalPage; )!P)U(*v
} :qd`zG3
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/** 5?]hd*8
* @param totalPage T9Nb`sbV]
* The totalPage to set. K/|Z$4S
*/ x$6^R q>2
publicvoid setTotalPage(int totalPage){ `ojoOB^L
this.totalPage = totalPage; u=`L)
} \nPEyw,U
t%E!o0+8Z
} sTn<#l6
hHV";bk
e,W%uH>X
NTYg[VTr
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?#}N1k\S
=A83W/4
个PageUtil,负责对Page对象进行构造: pHLB = r
java代码: hEKf6#
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cj$[E]B3V*
/*Created on 2005-4-14*/ UG+d-&~Ll
package org.flyware.util.page; _./Sk|C
1;Ou7T9w
import org.apache.commons.logging.Log; wea-zN
import org.apache.commons.logging.LogFactory; b4[bL2J$h1
lh7jux
/** Nn!+,;ut
* @author Joa W*Zkc:{eB
* DH\0z[
*/ : y%d
publicclass PageUtil { g/CSGIIT
\hDlTp}
privatestaticfinal Log logger = LogFactory.getLog ChGYTn`X
/|C*
(PageUtil.class); S4Y&
l]Ax : Z
/** UC]\yUK1J
* Use the origin page to create a new page =8AO:
* @param page K,+LG7ec
* @param totalRecords ~A'!2
* @return }`%*W`9b
*/ J&W)(Cf
publicstatic Page createPage(Page page, int |$8~?7Jv
c;Pe/ d
totalRecords){ zv0l,-o
return createPage(page.getEveryPage(), Yc_8r+;(
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page.getCurrentPage(), totalRecords); PgtJ3oq[}
} 1w@(5 ^V
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/** %5M/s'O?i
* the basic page utils not including exception zzTfYf)
e2s]{obf
handler u0|8Tgf
* @param everyPage }B\a<0L/
* @param currentPage )dbB=OZ
* @param totalRecords a{^m-fSaR"
* @return page
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*/ 0D\#Pq
v
publicstatic Page createPage(int everyPage, int [ 9 {*94M
+ jc!5i .
currentPage, int totalRecords){ Q=;U@k@>
everyPage = getEveryPage(everyPage); &"f";
currentPage = getCurrentPage(currentPage); V58wU:li
int beginIndex = getBeginIndex(everyPage, JTO~9>$ B
=,spvy'"*C
currentPage); nAW:utTB
int totalPage = getTotalPage(everyPage, Ugu[|,
l{I6&^!KS
totalRecords); #5cEV'm;
boolean hasNextPage = hasNextPage(currentPage, +ga k#M"n\
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totalPage); U}yW<#$+
boolean hasPrePage = hasPrePage(currentPage); T!+5[
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returnnew Page(hasPrePage, hasNextPage, ;RDh~EV
everyPage, totalPage, n0r+A^]
currentPage, gd%NkxmW
q)X$^oE!6
beginIndex); !=;+%C&8y
} @$S+ Ne[<
nw -xSS{
privatestaticint getEveryPage(int everyPage){ gw#5jW\
return everyPage == 0 ? 10 : everyPage; dgR
g>)V
} {MtpkUN
'&x#rjo#
privatestaticint getCurrentPage(int currentPage){ mHV%I@`Y6
return currentPage == 0 ? 1 : currentPage; N60rgSzI
} @e(o129
}Lc-7[/
privatestaticint getBeginIndex(int everyPage, int nzd2zY>V
sF!($k;!
currentPage){ G_;)a]v8)
return(currentPage - 1) * everyPage; Sj]T
} GPkmf%FJ
2D75:@JL}|
privatestaticint getTotalPage(int everyPage, int E7t+E)=8
7!@-*/|!S9
totalRecords){ EYtL_hNp}I
int totalPage = 0; 4 !i$4
wQqb`l7+
if(totalRecords % everyPage == 0) .{ocV#{s
totalPage = totalRecords / everyPage; zL$@`Eh-KP
else *w^C"^*
totalPage = totalRecords / everyPage + 1 ; f[<m<I
B:5Rr}eY+
return totalPage; K-bD<X
} *W.C7=
?k]2*}bz
privatestaticboolean hasPrePage(int currentPage){ >zw.GwN|
return currentPage == 1 ? false : true; 5b*M*e&=C
} K{&mI/;
wW7eT~w
privatestaticboolean hasNextPage(int currentPage, H5DC[bZMb%
Bc+w+
int totalPage){ rM`X?>iT+
return currentPage == totalPage || totalPage == iq8GrdL"
vI:;A/&
0 ? false : true; jr)1(**
} S=5<^o^h3
OVm\
X &uTSgN
} .Zn^Nw3
wT;0w3.Z
Z>QF#."m
+AR5W(&
8J:}%DaxL
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。 sF|5XjQ
x.7]/)
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 ;XF:\<+
cJ{ Nh;"
做法如下: I;e=0!9U
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \n$u)Xj~6^
,5i` -OI
的信息,和一个结果集List: `bFff%_
java代码: I KqQ>Z-q~
dCE0$3'5
< vL,*.zd
/*Created on 2005-6-13*/ -&NN51-d\j
package com.adt.bo; 6VS4y-N
wP6Fl L
import java.util.List; D&od?3}E
"Ue.@>
import org.flyware.util.page.Page; Mmxlp.l
5*+!+V^?X
/** Kf>A\l^X7
* @author Joa uD}2<$PP
*/ fmQ_P.c
publicclass Result { iL7DRQ1
R9'b-5q
private Page page; 0+?7EL~
OBMTgZHxv
private List content; /j4P9y^]=
5"CZh.J
/** igIRSN}h
* The default constructor kw#;w=\>R{
*/ D>HOn^
public Result(){ 6ys
&zy
super(); iI\oz&!vH
} [0(B>a3J
S0B|#O%Z
/** % W=b?:
* The constructor using fields Q9~*<I> h;
* =:&ly'QB&
* @param page W }8'Pf
* @param content qlb-
jL
*/ NL!u<6y
public Result(Page page, List content){ ABQa 3{v
this.page = page; >OL 3H$F
this.content = content; /q<__N
} nH`Q#ZFz]?
{t0)
q
/** q|j2MV5#g
* @return Returns the content. (a[y1{DLy
*/ {1IfU
publicList getContent(){ ZX>AE3wk
return content; %6t2ohO"
} \P j
Ka[t75~;
/** QIB\AAclO
* @return Returns the page. ]QpWih00V
*/ I/&%]"[^u
public Page getPage(){ )we}6sE"
return page; .} q&5v
} o<[#0T^K
|_] Q$q[[%
/** H=g`hF]`
* @param content G+%zn|
* The content to set. qT%FmX
*/ I$<<(VWH
public void setContent(List content){ d/ARm-D
this.content = content; eZSNNgD<:
} &X|#R1\
e7m*rh%5>
/** - db_E#
* @param page P+s!|7'
* The page to set. P*
w9,
*/ X' d9[).
publicvoid setPage(Page page){ $ {O#
this.page = page; %+j8["VEC
} j7jCm:
} ;%<,IdhN
@ o3T
=<{np
{)BTR %t
UmKI1l
2. 编写业务逻辑接口,并实现它(UserManager, \9cG36
eM$s v9?
UserManagerImpl) kS_(wpA
java代码: Fx;QU)1l3
Y&S24aql
YE|SKx@
/*Created on 2005-7-15*/ bmfI~8
package com.adt.service; E~]R2!9
}|g\ 8jq
import net.sf.hibernate.HibernateException; OW3sS+y
4kBaB
import org.flyware.util.page.Page; te3}d'9&|
mS~o?q-n
import com.adt.bo.Result; MUTj-1 H6)
`(YxI
/** yzerOL
* @author Joa 'eLqlu|T
*/ ^>i63Yc
publicinterface UserManager { ~yH?=:>U
sE:M@`2L
public Result listUser(Page page)throws 8,C*4y~
y~q8pH1
HibernateException; T)H{
H5Z$*4%G
} q35f&O;
Jtr"NS?a]
~/98Id}v
L3@82yPo!
nm6h%}xND<
java代码: ~]nSSD)\
;1%-8f:lW
W3MU1gl6k{
/*Created on 2005-7-15*/ y%%}k
package com.adt.service.impl; bgK'{_o-
7R6ry(6N
import java.util.List; E`?3PA8
[co% :xJu
import net.sf.hibernate.HibernateException; gP0LCK>
mj9 <%P
import org.flyware.util.page.Page; +VO-oFE |
import org.flyware.util.page.PageUtil; L&u$t}~)
Uk^B"y_
import com.adt.bo.Result; (C@m Lu)
import com.adt.dao.UserDAO; I@yCTluV$
import com.adt.exception.ObjectNotFoundException; K
i'Fn"
import com.adt.service.UserManager; !bN*\c
X*{2[+<o
/** _$
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* @author Joa |4B:<x
*/ "#{4d),r
publicclass UserManagerImpl implements UserManager { z^#;~I @M
{(r`k;fB
private UserDAO userDAO; 6)Y.7 XR
-OapVa c
/** ;#vKi0V7
* @param userDAO The userDAO to set. whi`Z:~
*/ 23Nw!6S
publicvoid setUserDAO(UserDAO userDAO){ ;\14b?TUH
this.userDAO = userDAO; ]x(e&fyHB
}
|8My42yf
u~WVGjoQ
/* (non-Javadoc) EfCx`3~EX
* @see com.adt.service.UserManager#listUser TFkZp e;
A
Q'J9
(org.flyware.util.page.Page) (9Ux{@$o[
*/ u>kN1k Q8
public Result listUser(Page page)throws YoBPLS`K
VQ7*Z5[1
HibernateException, ObjectNotFoundException { B9NWW6S
int totalRecords = userDAO.getUserCount(); g*03{l#P
if(totalRecords == 0) inh=WUEW
throw new ObjectNotFoundException apg=-^L'
|mGFts}0o'
("userNotExist"); $}>+kHoT{
page = PageUtil.createPage(page, totalRecords); +@p%
p
List users = userDAO.getUserByPage(page); W-?()dX{
returnnew Result(page, users); E5I"%9X0H
} 7"20hAd
-*
WXMzr
} U%q7Ai7
=kJ,%\E`
:h\Q;?
Ji>o!
w5A y)lz
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 BD_Iz A<wK
.Le?T&_
询,接下来编写UserDAO的代码: WtG~('g>&
3. UserDAO 和 UserDAOImpl: @+Si?8\
java代码: BJM.iXU)[
El.hu%#n*G
C8Qa$._
/*Created on 2005-7-15*/ 2+QY hdw
package com.adt.dao; S|7!{}
WvBc#s-
import java.util.List; +nXK-g;)'
c:<005\Bg
import org.flyware.util.page.Page; WST8SEzJ
Jk7|{W\OA
import net.sf.hibernate.HibernateException; {`LU+
x:),P-~w
/** m[~V/N3
* @author Joa Xejo_SV&?
*/ jL%x7?*U0
publicinterface UserDAO extends BaseDAO { 8Kg n"M3
*h!28Ya(~
publicList getUserByName(String name)throws r+":' /[x
rH_\d?b
HibernateException; }1Gv)l7
Cd,jDPrw
publicint getUserCount()throws HibernateException; FbS|~Rp~
PsnWWj?c
publicList getUserByPage(Page page)throws #_6I w`0
Q=AavKn#
HibernateException; :S<f?*
}:
xe{!wX
} x3 q]I 8q
^@3sT,M,S
OSs&r$
:Av#j@#
]s'Q_wh_-v
java代码: yeXx',]a
t&H?\)!4
5ymk\Lw
/*Created on 2005-7-15*/ piPR=B+
package com.adt.dao.impl; AgS7J(^&3
wQ^EYKD
import java.util.List; -:|?h{q?u
gp>3I!bo[K
import org.flyware.util.page.Page; g)#W>.Asd
L^}_~PO N5
import net.sf.hibernate.HibernateException; iII=;:p
import net.sf.hibernate.Query; )wC?T
}& cu/o4
import com.adt.dao.UserDAO; uJzG|$;
@ ;*Ksy@1O
/** (s.0PO`
* @author Joa c6h.iBJ'
*/ QRHu3w
public class UserDAOImpl extends BaseDAOHibernateImpl WI-&x
'
2oVSn"
implements UserDAO { O(fM?4w
ED=V8';D
/* (non-Javadoc) XGYbnZ~
* @see com.adt.dao.UserDAO#getUserByName h2Ld[xvCu%
)J2mM
(java.lang.String)
gbF+WE
*/ L2\#w<d
publicList getUserByName(String name)throws #M9~L[nFS
"I3@m%qv
HibernateException { ?zh9d%R
String querySentence = "FROM user in class A\4D79>x
-ws? "_w
com.adt.po.User WHERE user.name=:name"; #.rdQ,)<
Query query = getSession().createQuery pMw*9sX
IwQ"eUnK
(querySentence); 4!Fo$9
query.setParameter("name", name); NjVYLn<.r
return query.list(); FHj"
nB
} ]<ldWL
}AB,8n`
/* (non-Javadoc) 4 ezEW|S
* @see com.adt.dao.UserDAO#getUserCount() - Ajo9H
*/ ] eotc2?u
publicint getUserCount()throws HibernateException { jyZ (RB
int count = 0; aS{|uE]
String querySentence = "SELECT count(*) FROM = bfJ^]R
7%5z p|3
user in class com.adt.po.User"; @$ne{2J3
Query query = getSession().createQuery kZR8a(4D
HVi'eNgo
(querySentence); xN5)
count = ((Integer)query.iterate().next uxXBEq;
J%u=Ucdh
()).intValue(); ;rF\kX&Jh
return count; 2;k*@k-t
} h;p>o75O
<c2E'U)X
/* (non-Javadoc) MI/MhkS
?
* @see com.adt.dao.UserDAO#getUserByPage 94h]~GqNi
a!a-b~#cx
(org.flyware.util.page.Page) 5x5@t
:
*/ 3eb%OEMYk
publicList getUserByPage(Page page)throws Si_ _8D
Z"/p,A9W9|
HibernateException { uZNTHD
String querySentence = "FROM user in class h
k]
N6+@
6.sx?Y YM
com.adt.po.User"; CSJdvxb
Query query = getSession().createQuery ~-ia+A6GIV
]^yFaTfS
(querySentence); 8[a=OP
query.setFirstResult(page.getBeginIndex()) <^VJy5>
.setMaxResults(page.getEveryPage()); [)H&'5 +F
return query.list(); Ur9?Td'*>
} D9<!mH
N4v~;;@(
} Y\D!/T
n`#tKwWHYx
H=<S 9M
8m-U){r!U^
Njxv4cc
至此,一个完整的分页程序完成。前台的只需要调用 *w|:~g
SEo'(-5
userManager.listUser(page)即可得到一个Page对象和结果集对象 tI`Q /a5@
$mu^G t
的综合体,而传入的参数page对象则可以由前台传入,如果用 *1uKr9
o*-)Tq8GHE
webwork,甚至可以直接在配置文件中指定。 vmU@^2JSJ
Z?6%;n^ 54
下面给出一个webwork调用示例: @3) (BpFe
java代码: qyZ"
%Kz
J1,9kCO
(/z_Q{"N
/*Created on 2005-6-17*/ o2nv+fyW
package com.adt.action.user; o*b] p-
*QpMF/<?
import java.util.List; xe]y]
B;M?,<%FRU
import org.apache.commons.logging.Log; rA3$3GLQ-
import org.apache.commons.logging.LogFactory; vq0Vq(V=
import org.flyware.util.page.Page; 5yd MMb
lNz7u:U3
import com.adt.bo.Result; 'H3^e}
import com.adt.service.UserService; @ju@WY45$^
import com.opensymphony.xwork.Action; rNrxaRQ
RmI]1S_=
/** {
d=^}-^
* @author Joa ^|/TC!v]M
*/ ]3x?
publicclass ListUser implementsAction{ EMh7z7}Rr
ERUz3mjA/
privatestaticfinal Log logger = LogFactory.getLog ]_Vx{oT7
hW%TM3l}
(ListUser.class); ,`|3KE9
y<?kzt
private UserService userService; 0g
+7uGp:
l}a)ZeR1
private Page page; AS!?q
n4s+>|\M
privateList users; ./-5R|fN
Q!o'}nA
/* -C;^3R[
O
* (non-Javadoc) m!gz3u]rN
* wVX[)E\J
* @see com.opensymphony.xwork.Action#execute() 9{'N{
*/ aAZZ8V
publicString execute()throwsException{ }{,^@xdyW
Result result = userService.listUser(page); FTX=Wyr
page = result.getPage(); n3T>QgK
users = result.getContent(); <Q3oT
return SUCCESS; RU'=ERYC
} ?5+.`L9H
K`yRr`pW
/** 1Lc#m`Jln
* @return Returns the page. 6o!!=}'E[
*/ p09HL%~R
public Page getPage(){ -Y1e8H ='
return page; Z)e/!~""]
} i/65v
A^nvp!_
/** i{Uc6R6
* @return Returns the users. J; 3{3
*/ O%Scjm-^X
publicList getUsers(){ y_'Ub{w
return users; LSm$dK
} \<&m&%Zs
hjU::m,WX
/** [8P:?nDDL
* @param page }v@dL3{f
* The page to set. T] R|qlZ
*/ ySk R>y
publicvoid setPage(Page page){ sz5MH!/PJ
this.page = page; fWCo;4<5?
} x5|I
%G3h?3
/** GX)u|g
* @param users w~.f
* The users to set. wa(8Hl|Y
*/ '@cANGg7[
publicvoid setUsers(List users){ xVf|G_5$
this.users = users; 6 +Sxr
} z
F_M*8=
&LmJ!^#
/** $Ad{Z
* @param userService Eav[/cU
* The userService to set. 2`AY~i9
*/ jTf@l?|
publicvoid setUserService(UserService userService){ CHdX;'`*
this.userService = userService; aC^\(wp[
} heltgRt
} _ ?TN;
gMv.V{vD
)}''L{k-
q?,).x
nN
kJWn<5%ayg
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, K}2Erm%A@y
^aIPN5CK
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 qBU-~"2t
'WMh8)
么只需要: yID164&r
java代码: 1 da@3xaF
3ovWwZ8&
'UkxS b
<?xml version="1.0"?> `^91%f
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork A]y`7jJ
T\:4qETQF]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &d9{k5/+\
c4!^nk]
1.0.dtd"> osciZ'~
NnO~dRx{
<xwork> yxonRV$&
LO'**}vm
<package name="user" extends="webwork- t^VwR=i
Bm.afsM;
interceptors"> F^l[GdUosK
5VRYO"D:
<!-- The default interceptor stack name DDvh4<Hk
sJ\BF
--> HPpR.
<default-interceptor-ref 7t3X)Ah
|VKK#J/
name="myDefaultWebStack"/> C#QpQg2
Pl(Q,e7O]
<action name="listUser" "B8Q:
Tb A}BFT`
class="com.adt.action.user.ListUser"> D,m]CK'
<param ;1#H62Z*
Gk967pC
name="page.everyPage">10</param> 5Y?L>QU"
<result *v?`<)P#
du+y5dw
name="success">/user/user_list.jsp</result> ~Xr=4V:a+
</action> W"724fwu&
5&xB6|k
</package> =6xrfDbN8
&6DMk-
</xwork> 1h(0IjG8
3E7ULK
1m+p;T$
X"MB|Ny
so^lb?g
>82@Q^O
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 YgKZ#?*
w'L\?pI
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。 CF&NFSti^
|\w=u6jX
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 85lCj-cs
M=.:,wRm
xrlmKSPa
JROM_>mC
jNe`;o
我写的一个用于分页的类,用了泛型了,hoho 8 m5p_\&
P
D4Tz!F
java代码: $ oTdfb
NHB4y /2
SH3|sXH<
package com.intokr.util; 9Kr+\F
-8'C\R|J+
import java.util.List; Fd#?\r.
aHlcfh9|
/** nJbtS#`G4
* 用于分页的类<br> Cv
}Qwy
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "~`I::'c
* Z.d7U~_
* @version 0.01 ekI2icD
* @author cheng - *F(7$
*/ Kqun^"Df
public class Paginator<E> { H|,Oswk~-
privateint count = 0; // 总记录数
zG+R5:
privateint p = 1; // 页编号 4!$s}V=6
privateint num = 20; // 每页的记录数 >Wh}f3C
privateList<E> results = null; // 结果 U QE qX
vQ<90ZxqB
/** %509\;el
* 结果总数 zs%Hb48V
*/ vesJEaw7
publicint getCount(){ L{:9Cx!F
return count; ?P4w]a
} Pa(^}n|
`IOs-%s
publicvoid setCount(int count){
pnMEB,)
this.count = count; MzPzqm<
} hbU+Usx
r~+\
Y"rM
/** |\_^B
* 本结果所在的页码,从1开始 [qdRUV'
* ~jK{ ,$:=
* @return Returns the pageNo. *eIJwXE
*/ .R)PJc5^
publicint getP(){ x? ?pBhJH
return p; 79nG|Yj|\
} ;?W|#*=R
}>)@WL:q
/** (&&4J{`W9
* if(p<=0) p=1 J%V-Q>L
* XEC(P
* @param p dp++%:j
*/ qZ]pq2G
publicvoid setP(int p){ |"XPp!_uN
if(p <= 0) IC6gU$e
p = 1; u583_k%
this.p = p; $k0kk
} pX/n)q[
|UP `B|
/** @lCJ G!u
* 每页记录数量 7~&/_3
*/ PN0VQ/..
publicint getNum(){ Ad:TYpLD
return num; .P.z B}0=
} tyfTU5"x
ygeDcnvR]
/** U`,0]"Qk
* if(num<1) num=1 FW) x:2BG
*/ bfA=3S"0
publicvoid setNum(int num){ _FXZm50\g{
if(num < 1) ]E_h
num = 1; <WjF*x p
this.num = num; Vm5c+;
} o HMo>*?
qzI&<4
/** $KUos+%
* 获得总页数 qP2ekI:y
*/ \=+b}mKV
m
publicint getPageNum(){ )foq),2
return(count - 1) / num + 1; hdnTXs@z
} ET _W-
4Y,R-+f
/** _2k]3z?
* 获得本页的开始编号,为 (p-1)*num+1 1^_U;O:I
*/ I/M _p^
publicint getStart(){ 4
SHU
return(p - 1) * num + 1; Rop'e 8Q
} a\IP12F?
a^Tmu
/** |fxA|/s[<
* @return Returns the results. 0q.Ujm=,z
*/ vohoLeJTj
publicList<E> getResults(){ YFE&r
return results; 5nTY ?<x`k
} gzBy?r> r
[01.\eh
public void setResults(List<E> results){ xY+VyOUs
this.results = results; B;R.# ^@/
} s7g(3<(
"Vw m
public String toString(){ 1rKlZsZ#*
StringBuilder buff = new StringBuilder &FH2fMLQ
zG' "9kJx
(); )+6v
buff.append("{"); o;W`4S^
buff.append("count:").append(count); u5 {JQO
buff.append(",p:").append(p); i<H wTmm$
buff.append(",nump:").append(num); h Ggx
buff.append(",results:").append K=C!b?
: p{+G
(results); Ma'_e=+A
buff.append("}"); {cB+mh;mJ>
return buff.toString(); >N;F8v
} Ypeiy`.
U~}
U\_
} HDda@Jy
uch>AuF:
p8kr/uMP ;