Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 zA[0mkC?$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 < P`u}
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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 YX`7Hm,
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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 '3?\K3S4i
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。 /z}~zO
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分页支持类: VO"("7L
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java代码: -=(!g&0
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package com.javaeye.common.util; |m2X+s9
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import java.util.List; Ps 8%J;
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publicclass PaginationSupport { Qci4J
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publicfinalstaticint PAGESIZE = 30; n/h,Lr)Z
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privateint pageSize = PAGESIZE; HQB(*
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privateList items; D_x+:1(
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privateint totalCount; 6,9o>zT%H
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privateint[] indexes = newint[0]; 3"P }n
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privateint startIndex = 0; eQ&ZX3*}
. Z%{'CC
public PaginationSupport(List items, int 3K_A<j:
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totalCount){ f-%NaTI
setPageSize(PAGESIZE); [w -l?
setTotalCount(totalCount); KjQR$-
setItems(items); v.]Q$q^
setStartIndex(0); l\s U
} 3JVK
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public PaginationSupport(List items, int #H0dZ.$b0
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totalCount, int startIndex){ R%'^ gFk8
setPageSize(PAGESIZE); [3@):8
setTotalCount(totalCount); A$w4PVS
setItems(items); !U5Wr+83
setStartIndex(startIndex); ,%)6jYHR w
} T,VY.ep/
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public PaginationSupport(List items, int ' Tc]KXD6
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totalCount, int pageSize, int startIndex){ oIefw:FE,a
setPageSize(pageSize); ;vIrGZV<
setTotalCount(totalCount); Y_QH&GZ
setItems(items); [3!~PR]
setStartIndex(startIndex); d.P\fPSD
} u07pq4Ly
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publicList getItems(){ =X.9,$Y
return items; M6}3wM*4
} '60 L~`K
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publicvoid setItems(List items){ kbMYMx.[
this.items = items; Oj^,m.R
} Q_Gi]M9
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publicint getPageSize(){ PoT`}-9
return pageSize; |P%DkM*X
} D&/L:
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publicvoid setPageSize(int pageSize){ fF V!)Zj
this.pageSize = pageSize; OdB?_.+$
} T16{_
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publicint getTotalCount(){ Yk5}`d!:
return totalCount; [!U?}1YQ
} .;*s`t
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publicvoid setTotalCount(int totalCount){ wy}k1E'M
if(totalCount > 0){ .Fa4shNV
this.totalCount = totalCount; ZAXN6h
int count = totalCount / Y2?.}Z O
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pageSize; #jxe%2'Ot
if(totalCount % pageSize > 0) =-}[^u1
count++; fOMvj%T@2
indexes = newint[count]; zBe8,, e
for(int i = 0; i < count; i++){ `IY/9'vT
indexes = pageSize * !ki.t
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} }eRD|1
}else{ WuZ/C_
this.totalCount = 0; w18y}mS"H
} .k0~Vh2u
} A21N|$[
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publicint[] getIndexes(){ <E0UK^-}
return indexes; |USX[jm\
} J|w)&bV
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publicvoid setIndexes(int[] indexes){ MC{
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this.indexes = indexes; 44F`$.v96
} Rh>}rGvCUN
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publicint getStartIndex(){ qvv2O1c"A
return startIndex; r{rQu-|.
} Uv4`6>Ix
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publicvoid setStartIndex(int startIndex){ Y]3>7q%
if(totalCount <= 0) al[n,u
this.startIndex = 0; X 51Yfr
elseif(startIndex >= totalCount) oI#a_/w
this.startIndex = indexes A4]s~Ur
xSBc-u#< G
[indexes.length - 1]; eVM/uDD
elseif(startIndex < 0) dF~8XYo
this.startIndex = 0; >~Qr
else{ u3o#{~E/#
this.startIndex = indexes _Y[jyD1>
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[startIndex / pageSize]; G2^et$<{uU
} 4NdN<#Lr
} !0dNQ[$82
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publicint getNextIndex(){ Vo"RO$%ow*
int nextIndex = getStartIndex() + ^'ryNa;"
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pageSize; Usta0Ag
if(nextIndex >= totalCount) uZ=NSbYsA
return getStartIndex(); H/"lAXfb
else v%RP0%%{s
return nextIndex; A2nqf^b{#
} is@b&V]
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{
publicint getPreviousIndex(){ fks)+L'
int previousIndex = getStartIndex() - bN3#{l-`
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pageSize; i}~SDY
if(previousIndex < 0) nYJTKU
return0; l#}.^71+
else SC-
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return previousIndex; Q[d}J+l4{
} !S_^94 b@
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} cDI [PJ9
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抽象业务类 Zx d~c]n
java代码: Z?O*'#yn
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/** D3x /OyG(
* Created on 2005-7-12 q@jq0D)g
*/ k`x=D5s\
package com.javaeye.common.business; YOJ6w
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import java.io.Serializable; %G?;!Lz
import java.util.List; yA3wtm/?
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import org.hibernate.Criteria; "C*B,D*}:
import org.hibernate.HibernateException; yu;SH[{Wi
import org.hibernate.Session; Jx=hJ-FY
import org.hibernate.criterion.DetachedCriteria; @l0|*lo%
import org.hibernate.criterion.Projections; Rtjqx6-B;
import 0j_bh,zG#
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org.springframework.orm.hibernate3.HibernateCallback; \t|M-%&)4
import 1*
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org.springframework.orm.hibernate3.support.HibernateDaoS 4Ua>Yw0
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upport; )$Z=t-q
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import com.javaeye.common.util.PaginationSupport; ^Eo=W/
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public abstract class AbstractManager extends Zx$ol;Yd
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HibernateDaoSupport { :>81BuMvg
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privateboolean cacheQueries = false; efY8M2
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privateString queryCacheRegion; #%S0PL"x U
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publicvoid setCacheQueries(boolean ~S(^T9R
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cacheQueries){ p/]s)uYp$
this.cacheQueries = cacheQueries; (B`sQw@tu
} B/eaqJ
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publicvoid setQueryCacheRegion(String qSiWnN8D
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queryCacheRegion){ LP`CS849z2
this.queryCacheRegion = t%+$"nP
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queryCacheRegion; &2.+Igo|G
} F,v7ifo#f
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publicvoid save(finalObject entity){ 3q &k
getHibernateTemplate().save(entity); MTmO>V&O
} uu}-"/<~7
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publicvoid persist(finalObject entity){ lfS;?~W0k
getHibernateTemplate().save(entity); kX8=cL9G
} V-vlTgemwc
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); elbG\qXBp
} vR]mSX3)?
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publicvoid delete(finalObject entity){ iVeQ]k(u
getHibernateTemplate().delete(entity);
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} QHQj/)J8
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publicObject load(finalClass entity, ~n]NyVFP
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finalSerializable id){ %c1FwAC
return getHibernateTemplate().load },6*Y*?{
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(entity, id); ; J2-rh
} nW&$~d
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publicObject get(finalClass entity, T~:_}J
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finalSerializable id){ (C~dkR?
return getHibernateTemplate().get KW>VOW<.
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(entity, id); AP
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} tDU}rI8?
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publicList findAll(finalClass entity){ qT0_L
return getHibernateTemplate().find("from >
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" + entity.getName()); 0s!N@ ,T
} H PTHF
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publicList findByNamedQuery(finalString ;/aB)JZ5=
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namedQuery){ !5E9sk{)
return getHibernateTemplate CKN8z
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().findByNamedQuery(namedQuery); S[.5n]
} :H3(w| T/
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publicList findByNamedQuery(finalString query, ^#7viZ*
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finalObject parameter){ xBt<Yt"
return getHibernateTemplate EaCZx
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().findByNamedQuery(query, parameter); F_ _H(}d
} s79q5
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publicList findByNamedQuery(finalString query, excrXx
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finalObject[] parameters){ ,0FwBK
return getHibernateTemplate tNYJQ
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().findByNamedQuery(query, parameters); ,?fN#gc :
} /Q]:Uf.J
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publicList find(finalString query){ 7_1W:-A7W
return getHibernateTemplate().find rEg+i@~
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(query); $xQ"PJ2
} g"w)@*?K
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publicList find(finalString query, finalObject 4 ;^g MI9
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parameter){ v<%]XHN
return getHibernateTemplate().find XEa~)i{O
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(query, parameter); N JXa_&_
} jjYM3LQcdP
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public PaginationSupport findPageByCriteria QZ?O;K1|y
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(final DetachedCriteria detachedCriteria){ BQE{
return findPageByCriteria .Dc28F~t
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); !+5C{Hs2
} 4Fh&V{`W
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public PaginationSupport findPageByCriteria dG"K/|
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(final DetachedCriteria detachedCriteria, finalint <&KLo>B^
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startIndex){ ^zKt{a
return findPageByCriteria a4Ls^
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(detachedCriteria, PaginationSupport.PAGESIZE, (y%%6#bd
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startIndex); uAc@ Z-
} IPwj_jvw
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public PaginationSupport findPageByCriteria s bs[=LW4
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(final DetachedCriteria detachedCriteria, finalint `8mD7xsg$
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pageSize, fFjL pl
finalint startIndex){ U0!^m1U:
return(PaginationSupport) 0`V3s]%iu
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getHibernateTemplate().execute(new HibernateCallback(){ sg+ZQDF{x
publicObject doInHibernate z|Hy>|+
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(Session session)throws HibernateException { f2`P8$U)R
Criteria criteria = B{[f}h.n
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detachedCriteria.getExecutableCriteria(session); ~?2rGE
int totalCount = #Tup]czO
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((Integer) criteria.setProjection(Projections.rowCount bELIRM9
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[2
()).uniqueResult()).intValue(); )3BR[*u*
criteria.setProjection =X)Q7u".7
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(null); Y;'VosTD
List items = F_ ,L2J
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criteria.setFirstResult(startIndex).setMaxResults t|go5DXz4
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s=
(pageSize).list(); 5{8x*PSl
PaginationSupport ps = pQk=x T
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new PaginationSupport(items, totalCount, pageSize, cWgbd^J
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startIndex); Vf"O/o}hq,
return ps; x{=[w`
} ERUs0na]
}, true); #> 7')G
} pg}~vb"
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public List findAllByCriteria(final JRHf.?
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate A/ 7r:yO
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().execute(new HibernateCallback(){ @SKO~?7T
publicObject doInHibernate Y1$ #KC
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(Session session)throws HibernateException { 6V.awg,
Criteria criteria = 8#X?k/mzU
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detachedCriteria.getExecutableCriteria(session); ,[Dh2fPM,
return criteria.list(); S4#A#a2J
} N>uA|<b,
}, true); S^3g]5YX
} [$hptQv
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public int getCountByCriteria(final #)W8.
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DetachedCriteria detachedCriteria){ ?l)}E
Integer count = (Integer) ^Nd|+}
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getHibernateTemplate().execute(new HibernateCallback(){ tqff84
publicObject doInHibernate `f\5p+!<7R
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(Session session)throws HibernateException {
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Criteria criteria = -_y~rx
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detachedCriteria.getExecutableCriteria(session); dAu^{1+2
return &,m'sQ
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criteria.setProjection(Projections.rowCount ?)A]q'
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()).uniqueResult(); G=r(SJq
} Gk{
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}, true); 4
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return count.intValue(); t-v^-#
} 9s;!iDFn
} xHM&csL
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用户在web层构造查询条件detachedCriteria,和可选的 fl
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 qB+:#Yrx/
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PaginationSupport的实例ps。 m~= ]^e
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ps.getItems()得到已分页好的结果集 2.HZ+1
ps.getIndexes()得到分页索引的数组 %0ll4"
ps.getTotalCount()得到总结果数 eZ8Y"i\!y
ps.getStartIndex()当前分页索引 {f@xA
ps.getNextIndex()下一页索引 J9b?}-O)
ps.getPreviousIndex()上一页索引 Z-? Iip{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ux%\Y.PPI
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Xa? 6#
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一下代码重构了。 g9FVb7In_
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我把原本我的做法也提供出来供大家讨论吧: 5CH-:|(;=
S`GXiwk
首先,为了实现分页查询,我封装了一个Page类: C$AIP\j-
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java代码: 3]:p!Y`$
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/*Created on 2005-4-14*/ *0Wi^f
package org.flyware.util.page; H}jK3;8E
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/** 6]@|7|N>X
* @author Joa fwnYzd3
* U&Sbm~Qi
*/ K=!ZI/+ju
publicclass Page { 2-cU -i4
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/** imply if the page has previous page */ HdY3DdC%q
privateboolean hasPrePage; (IoPU+1b
SBN_>;$c5}
/** imply if the page has next page */ V(''p{
privateboolean hasNextPage; =}%#$
pb/{ss+
/** the number of every page */ ZVL-o<6
privateint everyPage; !Z+*",]_
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/** the total page number */ TY54e T
privateint totalPage; JT.\f,z&
fo!Lp*'0
/** the number of current page */ .qqb>7|q
privateint currentPage; \ ]kb&Qw
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/** the begin index of the records by the current f>wW}-
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query */ v8'`gY
privateint beginIndex; y3@x*_K8
(Q h7bfd
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/** The default constructor */ r0?hX
public Page(){ p~d)2TC4#
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} sS1J.R
o7@4=m}
/** construct the page by everyPage SqA+u/"j2
* @param everyPage ?ck^? p7
* */ eRl?9
public Page(int everyPage){ wzQdKlV
this.everyPage = everyPage; j$mt*z L
} Q,,fDBN
ko+M,kjwR
/** The whole constructor */ a`@<Z sR
public Page(boolean hasPrePage, boolean hasNextPage, jB/q1vFO
ev;5?9\E
"- j@GCme
int everyPage, int totalPage, I3zitI;
int currentPage, int beginIndex){ ,QHx*~9
this.hasPrePage = hasPrePage; M#lVPXS
this.hasNextPage = hasNextPage; G5QgnxwP2
this.everyPage = everyPage; /nMqEHCyg
this.totalPage = totalPage; Vm1 c-,)3
this.currentPage = currentPage; Xv5Ev@T
this.beginIndex = beginIndex; Y(I*%=:$
} |H+k?C-w
dV2b)p4J
/** EhP&L?EL
* @return Bn#HJ17/#
* Returns the beginIndex. ]N(zom_0d
*/ Dpp52UnTE
publicint getBeginIndex(){ Ng;b!S
return beginIndex; ?D
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} 1TxhE XB
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/** ]-s`#
* @param beginIndex _9O }d
* The beginIndex to set. 4Utx
9^
*/ #;*ai\6>vD
publicvoid setBeginIndex(int beginIndex){ A^Hp #b@
this.beginIndex = beginIndex; 9
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} %wjU^Urya
*(SBl}f4l
/** A$"$`)P!
* @return #u=O 5%.
* Returns the currentPage. M4hN#0("4
*/ %CE@}
publicint getCurrentPage(){ o2e h)rtB
return currentPage; CIik@O*
} ;,B@84'
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/** piiQ
* @param currentPage 98%tws`
* The currentPage to set. ?xTeio44
*/ >'1Q"$;
publicvoid setCurrentPage(int currentPage){ +!V%Q
this.currentPage = currentPage; DIu72\
} gmAKW4(
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/** ?e_}X3{
* @return R?9Plzt5
* Returns the everyPage. WlLZtgq
*/ lSbM)gL
publicint getEveryPage(){ ~z1KD)^
return everyPage; wsGq>F~
} NMY!-Kv 5
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/** LYq2A,wm$
* @param everyPage (PrPH/$
* The everyPage to set. <ZvPtW
*/ BLH3$*,H
publicvoid setEveryPage(int everyPage){ fm:{&(
this.everyPage = everyPage; zUgkY`]:BJ
} G-i_s6Wu
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/** .idl@%
* @return -I-&<+7v
* Returns the hasNextPage. e"H+sM26-
*/ {)[g
publicboolean getHasNextPage(){ |b;M5w?
return hasNextPage; 6C51:XQO
} oD}FJvV
WT
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/** Vq7
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* @param hasNextPage <C`eZ}Qqv
* The hasNextPage to set. r|F,\fF
*/ <@j
publicvoid setHasNextPage(boolean hasNextPage){ Uus)2R7
this.hasNextPage = hasNextPage; x
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} ! tPK"k
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/** L8K 3&[l%
* @return :8L61d2(
* Returns the hasPrePage. gV44PI6h
*/ 9* Twx&
publicboolean getHasPrePage(){ 0m!ZJH e
return hasPrePage; ^Jpd9KK
} 4_:e+ ql
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/** k+G4<qw
* @param hasPrePage 5.HztNL
* The hasPrePage to set. *ik)>c_
*/ vgZPDf|
publicvoid setHasPrePage(boolean hasPrePage){ E
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this.hasPrePage = hasPrePage; ';!UJWYl
} \mit&EUh}
p
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/** s"F,=]HQ!G
* @return Returns the totalPage. Yy~ Dg
* 9JeGjkG,
*/ /!8:/7r+W
publicint getTotalPage(){ XxQ2g&USk
return totalPage; xW )8mv?4n
} -xEg"dY/
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/** ]>!_OCe&
* @param totalPage sJYX[
* The totalPage to set. *hgsS~
*/ ~2;y4%K
publicvoid setTotalPage(int totalPage){
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this.totalPage = totalPage; Y mSaIf
} t~#+--(
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} -0){C|,6
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Ase 1 R=0
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Ok"wec+,
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 9uo\&,,
7En~~J3
个PageUtil,负责对Page对象进行构造: N.J:Qn`(
java代码: EE{%hGb
sAj$U^Gp
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/*Created on 2005-4-14*/ XwGJ 8&N
package org.flyware.util.page;
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import org.apache.commons.logging.Log; wOSNlbQ5jl
import org.apache.commons.logging.LogFactory; O3^@" IY
O$ \N]#
/** L(YT6Vmm+t
* @author Joa sbb{VV`I
* FpYoCyD}
*/ I!%@|[ Ow
publicclass PageUtil { `Q[$R&\
e=C,`&sz
privatestaticfinal Log logger = LogFactory.getLog ]vG)lY.=
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(PageUtil.class); '/@VG_9L]
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/** v7RDoO]I
* Use the origin page to create a new page riQ?'!a7
* @param page {rr\hl-$
* @param totalRecords Ds$;{wl#x
* @return +d.Bf
*/ H$HhB8z3
publicstatic Page createPage(Page page, int /$Jh5Bv
kSrzIq<xre
totalRecords){ 3x$ #L!VuU
return createPage(page.getEveryPage(), uDUSR+E>
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page.getCurrentPage(), totalRecords); q2Dg~et
} 0J B"@U&-
9)`wd&!
/** g [K8G
* the basic page utils not including exception Sx7xb]3XI"
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handler $1F9TfA
* @param everyPage 7KLq-u-8
* @param currentPage q
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* @param totalRecords # jyAq$I0
* @return page /fEXAk
*/ ME"/%59r
publicstatic Page createPage(int everyPage, int QS_xOQ '
}#@LZ)]hK
currentPage, int totalRecords){ U/;Vge8{
everyPage = getEveryPage(everyPage); Smo'&x
currentPage = getCurrentPage(currentPage); ?M);wBe(
int beginIndex = getBeginIndex(everyPage, m;|I}{r
XooAL0w
currentPage); {WChD&v
int totalPage = getTotalPage(everyPage, W&nVVV8s@
m"5gzH
totalRecords); %vI]"a@
boolean hasNextPage = hasNextPage(currentPage, psBBiHB[L
}T@AoIR0t
totalPage); Yi3DoaS;"
boolean hasPrePage = hasPrePage(currentPage); 2P*O^-zRp
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returnnew Page(hasPrePage, hasNextPage, E^G=
everyPage, totalPage, -ydT%x
currentPage, o5d)v)Rx=
@r<w|x}
beginIndex); )!Bv8&;e
} _XN sDW4|
3z#16*
privatestaticint getEveryPage(int everyPage){ "&~Um U4CN
return everyPage == 0 ? 10 : everyPage; GauIe0qV
} p("do1:
_?8T'?-1
privatestaticint getCurrentPage(int currentPage){ :D EZ$gi
return currentPage == 0 ? 1 : currentPage; =619+[fK
} e |!i1e!
b=sc2)3?
privatestaticint getBeginIndex(int everyPage, int t_3XqjuA
n#iL[
&/Aw
currentPage){ Y,{X v
return(currentPage - 1) * everyPage; '<O&
:
} !GO4cbdQ
9tJiIr8i
privatestaticint getTotalPage(int everyPage, int S;=
D/)[mr
e(b*T
totalRecords){ a"}?{
int totalPage = 0; :`d& |BB
z5?xmffB
if(totalRecords % everyPage == 0) Vki3D'.7N
totalPage = totalRecords / everyPage; |zSkQ_?54
else ^z_~e@U
totalPage = totalRecords / everyPage + 1 ; ?>e-6*.
&N,c:dNe
return totalPage; ibh!8" [
} \D0Pik@?
IRLT-
privatestaticboolean hasPrePage(int currentPage){ V7.EDE2A3
return currentPage == 1 ? false : true; =OCHV+m
} A@GyKx%x$
4Vh#Ye:`
privatestaticboolean hasNextPage(int currentPage, z.FO6y6L
m)&2zV/Q
int totalPage){ z@dHXj )
return currentPage == totalPage || totalPage == rB-&'#3%
,?728pfw
0 ? false : true; & GX
pRo
} -(P"+g3T
0 }
uH
PKk_9Xd
} .:E%cL
+h
zl$'W=[rFs
so1%
MV
K^>+"
{eL XVNR7R
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ~'n3],o?
;BsyN[bF
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 }<m9w\pA
i.Yz)Bw
做法如下: Cjdw@v0;
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 N"Q-xK
>yiK&LW^?
的信息,和一个结果集List: Y<odXFIS
java代码: <7-3j{065
U,\3 !D0jt
Qt`}$]
/*Created on 2005-6-13*/ P`0}( '"U
package com.adt.bo; =c:K(N qL
1$H*E~
import java.util.List; Z$"E|nRN
qX>mOW^gT8
import org.flyware.util.page.Page; F[5[@y
eT0Yp
/** 5=(fuY3
* @author Joa 7S|nn|\Kp
*/ j&~`H:=E
publicclass Result { =f4>vo}@k
JlR(U."
private Page page; ,6J]oX
'W(!N%u
private List content;
j#6@cO'`
/** 2[zFKK
* The default constructor 5FKb7
*/ Z#+lwZD
public Result(){ CEzwI _
super(); iEjUo,
Y[
} F|nJ3:v
<2{g[le
/** ROb2g|YXG
* The constructor using fields ky R=U`OW
* GI']&{
* @param page v"-@'qN'
* @param content d|I?%LX0p
*/ kzozjh%`9h
public Result(Page page, List content){ "h58I)O
this.page = page; ;tg9$P<85
this.content = content; ?o$ hlX
} J%r$jpd'
3M~*4
/** J?DJA2o
* @return Returns the content. =zBc@VTp
*/ c{4Y?SSx
publicList getContent(){ 0q}k"(9
return content; GE?M. '!{{
} 6)5Akyz4V
A}"aH
/** fRlO.!0(
* @return Returns the page. U}hQVpP#
*/ )a99@`L\P
public Page getPage(){ T3H\KRe6
return page; ol#|
.a2O
} m6+4}= Cn
Lgr(j60s
/** -0P(lkylf
* @param content #z$g1\v
* The content to set. |
6/ # H*
*/ Ga,+
public void setContent(List content){ U?/C>g%/PI
this.content = content; jc0Trs{Jf
} <e)u8+(
Le,e,#hiY
/** 7^bde<0
* @param page R-[t4BHn
* The page to set. SyL:=NZ
*/ <?h,;]U
publicvoid setPage(Page page){ &GKtD)
this.page = page; E'KKR1t
} qL;u59
} x b6X8:
u*w'.5l
lX)ZQY:= :
:n0czO6E
.G/>X%X
2. 编写业务逻辑接口,并实现它(UserManager, e<Bwduy
)Up'W
UserManagerImpl) -mfd ngp3
java代码: CO5>Q o
K+P:g%M
%Eq4>o?D
/*Created on 2005-7-15*/ P&$ m2^K
package com.adt.service; }}s.0Q
oEJYAKN
import net.sf.hibernate.HibernateException; &\p=s.y?j
EEI!pi
import org.flyware.util.page.Page; wbImE;-Z
$v \@mW*R
import com.adt.bo.Result; D}i_#-^MH
P;' xa^Y
/** rfH'&k
* @author Joa .e Jt]K
*/ f=,(0ygt/
publicinterface UserManager { f%gdFtJ &
q'9}Hz
public Result listUser(Page page)throws 'h*^;3@*
]ucz8('
HibernateException; X}5}M+'~
LkK# =v
} ;}W-9=81
a9%^Jvm"
HAca'!p
UB9n7L(@c
Ms61FmA4
java代码: ZvVrbj&
JlMD_p A
$-#|g
/*Created on 2005-7-15*/ $C^tZFq
package com.adt.service.impl; oU[>.Igi
F?y4 L9|e
import java.util.List; aMq|xHZ
]IQ`.:g=9
import net.sf.hibernate.HibernateException; 3;-P (G@
@!np
0#
import org.flyware.util.page.Page; "j*{7FBqk
import org.flyware.util.page.PageUtil; r@)_>(
NW%u#MZ[h
import com.adt.bo.Result; &ZR} Z7E*=
import com.adt.dao.UserDAO; OA?pBA
import com.adt.exception.ObjectNotFoundException; 40i]I@:JK
import com.adt.service.UserManager; u|eV'-R)s
w$fP$ \+
/** +BaZl<ZP1s
* @author Joa A@81wv
*/ }#D+}Mo!,
publicclass UserManagerImpl implements UserManager { sc)}r_|g
'jr[
?WQ
private UserDAO userDAO; WJA0 `<~
-qW[.B
/** y(92 Th$
* @param userDAO The userDAO to set. D.;iz>_}Y
*/ RASPOc/]
publicvoid setUserDAO(UserDAO userDAO){ \.l8]LH
this.userDAO = userDAO; ?BA~$|lfxu
} @)<
3Z
|08'd5
/* (non-Javadoc)
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* @see com.adt.service.UserManager#listUser At$[&%}
I|eYeJ3
(org.flyware.util.page.Page) m6 V L
*/ edZhI
public Result listUser(Page page)throws eWw#
T^
;GF+0~5>
HibernateException, ObjectNotFoundException { :41Ch^\E
int totalRecords = userDAO.getUserCount(); X:kqX[\>
if(totalRecords == 0) w;=g$Bn
throw new ObjectNotFoundException kl+^0i
|J+oz7l?-
("userNotExist"); d:&=|kKw
page = PageUtil.createPage(page, totalRecords); hwj:$mR
List users = userDAO.getUserByPage(page); 2^f6@;=M
returnnew Result(page, users); !QXPn}q^0
} M9ACaf@
E Z+L'
} tmVGJ+gz
}T1.~E
Y)*:'&~2e
S|pf.l
)0UXTyw^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7%)KB4(\_
\iQ{Q&JR:
询,接下来编写UserDAO的代码: 5SQqE@g%
3. UserDAO 和 UserDAOImpl: Ef2i#BoZ
java代码: |SSe n#PYp
:ND e<6?u
tcD DX'S
/*Created on 2005-7-15*/ &|Cd1z#?
package com.adt.dao; Je &O
u?%FD~l:uU
import java.util.List; 9ymx;
@CNe)&U
import org.flyware.util.page.Page; +.pri
~/l5ys
import net.sf.hibernate.HibernateException; eFXQ~~gOj
_/[}PQC6G
/** &qMt07
* @author Joa /#-zI#iK
*/ C.N#y`g
publicinterface UserDAO extends BaseDAO { pSKwXx
A(}D76o_
publicList getUserByName(String name)throws }-N4D"d4o
hUP?r/B
HibernateException; 5[0W+W
M'5PPBSR
publicint getUserCount()throws HibernateException; z{wZLqG
q#_<J1)z
publicList getUserByPage(Page page)throws =x3T+)qCNX
PFI^+';
HibernateException; M.u1SB0
%pj T?G7
} GWW#\0*Bn
S=_*<[W%4
:zp9L/eh
JJ4w]Dd4
4)Ab]CdD
java代码: !t!'
ap wA
B+4WnR1%T
/*Created on 2005-7-15*/ +HkEbR'G0
package com.adt.dao.impl; [pX cKN
p|n!R $_g\
import java.util.List; ( q}{;
J*D3=5&
import org.flyware.util.page.Page; %(A@=0r#
Rg SB?
import net.sf.hibernate.HibernateException; [oG
Sy5bB
import net.sf.hibernate.Query; >=K~*$&>
4|h>.^
import com.adt.dao.UserDAO; O&}`R5Y;
OLE@35"v]
/** 3U4h>T@s|
* @author Joa Z)!#+m83>-
*/ xp%LXxj
public class UserDAOImpl extends BaseDAOHibernateImpl L*zfZ&
&I7T?
implements UserDAO { 48LzI@H&
51'{Jx8
/* (non-Javadoc) iJb-F*_y
* @see com.adt.dao.UserDAO#getUserByName <(_${zR
paZcTC
(java.lang.String) L8?;A9pc()
*/ sWFw[Y>
publicList getUserByName(String name)throws qJK-HF:#
l
9bg
HibernateException { 4%*`'o$_
String querySentence = "FROM user in class o?><(A|
xM13OoU
com.adt.po.User WHERE user.name=:name"; yX1OJg[s,
Query query = getSession().createQuery J~lKN
<w
9d8U@=
(querySentence); pykRi#[UrX
query.setParameter("name", name); #K\;)z(?
return query.list(); Y0g6zHk7
} K-n]m#U4o
3yu,qb'"&
/* (non-Javadoc) ~`<_xIvrq
* @see com.adt.dao.UserDAO#getUserCount() 0pA>w8 mh
*/ Q+Ya\1$6A
publicint getUserCount()throws HibernateException { W <M\b#
int count = 0; LEA^o"NW.
String querySentence = "SELECT count(*) FROM uZ+vYF^
]]/p.#oD,
user in class com.adt.po.User"; VE*&t>I
Query query = getSession().createQuery ZqfoO!Ta
\=
Wrh3
(querySentence); vnH[D)`@
count = ((Integer)query.iterate().next 1G
63eH)!
YiC_,8A~
()).intValue(); A2"$B\j1
return count; rQ&F Gb
} yD(v_J*
.2/W.z2
/* (non-Javadoc) o_?A^u
* @see com.adt.dao.UserDAO#getUserByPage GtkZ%<KF9
/igbn
(org.flyware.util.page.Page) vR'rYDtU@
*/ A~#w gLGn
publicList getUserByPage(Page page)throws qQe23,x@5
Bu#\W
HibernateException { o&kgRv[
String querySentence = "FROM user in class ;\gHFG}
=QW:},sp
com.adt.po.User"; ;{ESo?$*
Query query = getSession().createQuery 9FmX^t$T
;"+]bne~
(querySentence); we2D!Ywr
query.setFirstResult(page.getBeginIndex()) SAN/fnM
.setMaxResults(page.getEveryPage()); 7=pJ)4;ZA
return query.list(); {WN??eys,
} ~k/GmH
bj U]]
} ~19&s~
]VHO'z\m
Nx<%'-9)|
NEcE-7aT
ZqJyuTPv
至此,一个完整的分页程序完成。前台的只需要调用 h|XLL|:
Gcd'- 1
userManager.listUser(page)即可得到一个Page对象和结果集对象 U$AV"F&!&}
:DR}lOi`
的综合体,而传入的参数page对象则可以由前台传入,如果用 HbQ+:B]
p$zj2W+sN
webwork,甚至可以直接在配置文件中指定。 afj[HJbY
jt4c*0z
下面给出一个webwork调用示例: rT28q.
java代码: F;<cG`|Rx
<#No t1R
OjBg$f~0F
/*Created on 2005-6-17*/ ip2BvN&
package com.adt.action.user; kY]^~|i6
ky|Py
import java.util.List; G|.5.FK^
SZm&2~|J
import org.apache.commons.logging.Log; Zh3hCxXa
import org.apache.commons.logging.LogFactory; Q*l_QnfG
import org.flyware.util.page.Page; U+'h~P'4
dEW I8Q]
import com.adt.bo.Result; I-o|~
import com.adt.service.UserService; ylBjuD+
import com.opensymphony.xwork.Action; i9quP"<9
<jHo2U8/"s
/** [+z*&~'
* @author Joa 6qkMB|@Ix
*/ $(ei<cAV
publicclass ListUser implementsAction{ R,KoymXP
*/E5<DO
privatestaticfinal Log logger = LogFactory.getLog =U_O;NC
}='1<~0
(ListUser.class); <ZgbmRY8
M3/_E7Qoj
private UserService userService; l[Rl:k!
0ntf%#2{
private Page page; = ,^eQZR:
T{Y;-m
privateList users; @>SirYh
o@blvW<v7
/* CJ#1j>
* (non-Javadoc) ^E`SR6_cmj
* .Pi8c[
* @see com.opensymphony.xwork.Action#execute() D_)n\(3
*/ zTQTmO
publicString execute()throwsException{ c&n.JV
Result result = userService.listUser(page); '}.Z' %;
page = result.getPage(); !pG_MO
users = result.getContent(); x cA5
return SUCCESS; .iXIoka
} jj8h>"d
?5MOp
/** 95^A !
* @return Returns the page. yttIA/
*/ tf_<w?~
public Page getPage(){ AQa;D2B$
return page; GI$7uR}
} CAvyS
BA t0YE`-,
/** m C&*K
* @return Returns the users. Uel^rfE`
*/ T\Ld)'fNv
publicList getUsers(){ K,Z_lP_~Vw
return users; i$:QOMA
} M
h5>@-fEE
A9L
{c!|-
/** F;;\I
* @param page %an&lcoX
* The page to set. N% W298
*/ 0281"aO
publicvoid setPage(Page page){ c-gpO|4>
this.page = page; POtwT">z
} 6o!Y^^/U
V'jvI
/** 5fqQ;r
* @param users "hi)p9 _cR
* The users to set. HE0@`(mCpa
*/ 98x&2(N
publicvoid setUsers(List users){ >p;cbp[ht
this.users = users; #)hJ.0~3
} Bp>Z?"hTe
1L\\](^
3
/** #2\
0#HN
* @param userService xpjv@P
* The userService to set. aHdXlmL
*/ [~#]p9|L
publicvoid setUserService(UserService userService){ ql_GN[c/
this.userService = userService; uiQR RT
} yE4X6
} m/(f?M l
>wOqV!0<
e qzmEg
OX!<{9o
\Q m1+tg
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, />,KWHR|:
12JmSvD
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 x%d\}%]
XFv) ]_G
么只需要: s}5,<|DL
java代码: e0; KmQjG
VA^yv1We
[9U::
<?xml version="1.0"?> 0V_dg |.
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6mAaFDI,R
+J<igb!S
1.0//EN" "http://www.opensymphony.com/xwork/xwork- >/5'0n_R
6Yu&'[?H$
1.0.dtd"> -0o1iU7
Hk8pKpn3
<xwork> `C +>PCO
O<KOsu1WW
<package name="user" extends="webwork- B{ptP4As-
VwKo)zH
interceptors"> rMy(NAo_
'W2B**}
<!-- The default interceptor stack name =Mby;wQ?|
q{:]D(
--> )EhRqX9
<default-interceptor-ref @j/|U04_Z
.Fe_Z)i>h
name="myDefaultWebStack"/> [W#M(`}D
:3aZ_
<action name="listUser" aI'MVKwMk
TyG;BF|rwk
class="com.adt.action.user.ListUser"> UcI;(Va
<param b|'{f?
,K>q{H^
name="page.everyPage">10</param> 4[o/p8*/
<result cU
W#@Mx
name="success">/user/user_list.jsp</result> V9dJNt'Ui
</action> 41Nm+$m
zD z"Dn9
</package> ;?K>dWf3f
}S,KUH.
</xwork> s=BJ7iU_68
Y:-O/X
Q%Fa1h:2&
nA)KRCi
[d^ [Y:I'\
#vs=yR/tn{
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 dPmtU{E<M
e_v_y$
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。 )@,zG(t5;
qwomc28O
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 abgAUg)
X<*-d6?gD`
L63B# H"
M?QK4Zxb6U
|q+dTy_n
我写的一个用于分页的类,用了泛型了,hoho |[B JZ
8uD%
java代码: #x|IEjoa
7~2c"WE
E-?@9!2
&
package com.intokr.util; 8[\~}Q6
|ycN)zuE
import java.util.List; >5c38D7k)
(BG
wBL
/** 7~
=r9-&G
* 用于分页的类<br> :|PI_
$4H
* 可以用于传递查询的结果也可以用于传送查询的参数<br> .wvgHi
* $z[r(a^a
* @version 0.01 kX8Ey
* @author cheng _p^&]eQ+k#
*/ *\"+/
public class Paginator<E> { >tQ$V<YB
privateint count = 0; // 总记录数 S #6:!
privateint p = 1; // 页编号 d:{#Dk#
privateint num = 20; // 每页的记录数 f C_H0h3
privateList<E> results = null; // 结果 [MI ?
GsU.Lkf
/** a^7QHYJ6
* 结果总数 3*#$:waGd
*/ Qt.|YB8
publicint getCount(){ TFDzTD
return count; ?\_vqW
} (g0U v.*
<z8z\4Hz
publicvoid setCount(int count){ 2?kVbF
this.count = count; N9 TM
} :;K Q]<
p<c1$O*
/** d#|%h]
6
* 本结果所在的页码,从1开始 ;E0x#JUrw
* C=(~[ Y
* @return Returns the pageNo. 't+'rG6x
*/ `$XgfMBf |
publicint getP(){ L~*nI d
return p; {Zo*FZcaX
} @./@"mR<
S^{tRPF%d
/** th}&|Y)T2
* if(p<=0) p=1 sNZOm $
* H/l,;/q]b
* @param p &Z%'xAOGR
*/ UaBNoD
publicvoid setP(int p){ Kh{_BdN
if(p <= 0) }ISR +./+
p = 1; )kIjZ
this.p = p; kH?PEA! \
} 6kO+E5;X
l $0w 9Z^
/** ! q+>'Mt
* 每页记录数量 h9QQ8}g
*/ u.2^t:A
publicint getNum(){ Ct]? /
return num; e}ivvs2
} rBZ00}
p1s|JI
/** \~.elKw<U
* if(num<1) num=1 B-V
*/ n/^QPR$>.
publicvoid setNum(int num){ -Fc 9mv(H
if(num < 1) S*%:ID|/C2
num = 1; X/H2c"!t
this.num = num; G$s=P
} $E^*^({
A:*$r Hbzl
/** +f,I$&d.V
* 获得总页数 OT#foP
*/ R^rA.7T
publicint getPageNum(){ |T{ZDJ+
return(count - 1) / num + 1; W3&~[DS@~
} ZK8DziO
1~[GGl
/** qG0gc\C}
* 获得本页的开始编号,为 (p-1)*num+1 `tm(3pJ
*/ QY$4D;M`g6
publicint getStart(){ 29NP!W
/g
return(p - 1) * num + 1; X:W}S/
} ihIRB9
cyWDtq
/** n;k
B_i*l
* @return Returns the results. bjFND]p?w
*/ hcQv!!Q"k$
publicList<E> getResults(){ M B,Z4 ^
return results; [}y"rs`!
} WiFZY*iu5
>k(AQW5?
public void setResults(List<E> results){ y|YhDO
this.results = results; =GLMdhD]
} s_76)7
;
. hTfxE0
public String toString(){ ]v.Yt/&C{
StringBuilder buff = new StringBuilder /!-ypIY
e_Q(l'f
(); AmcBu"
buff.append("{"); "H}ae7@
buff.append("count:").append(count); VqeW;8&*iv
buff.append(",p:").append(p); Xa[lX8$zL
buff.append(",nump:").append(num); HA.
O"A8`
buff.append(",results:").append cQ/T:E7$`
s=n_(}{ q
(results); <@=w4\5j9
buff.append("}"); x2+M0 }g
return buff.toString(); ; T WYO
} 1JN/oq;
k)JwCt.%
} UbSD?Ew@35
IO?6F@(
U6 H@l#