Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 L4T\mP7D7*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fQ"Vx!
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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 [_`yy
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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 : O@(Sv
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。 h4itXJy52B
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分页支持类: 'AWWdz
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java代码: 9=6BQ`u
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package com.javaeye.common.util; t' J4zV
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import java.util.List; 'Lu xF1>
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publicclass PaginationSupport { %-$
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publicfinalstaticint PAGESIZE = 30; kG9aHWw
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privateint pageSize = PAGESIZE; tUZfQ
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privateList items; LttA8hf5q?
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privateint totalCount; ,4XOe,WQ
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privateint[] indexes = newint[0]; p ^TCr<=
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privateint startIndex = 0; 7JuHa /Mv
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public PaginationSupport(List items, int \(=xc2
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totalCount){ |;(P+Q4lB
setPageSize(PAGESIZE); IO7gq+
setTotalCount(totalCount); A /c
setItems(items); /E{tNd^S
setStartIndex(0); LkK&<z
} -Vb5d!(
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public PaginationSupport(List items, int 8 l= EL7
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totalCount, int startIndex){ |{-?OOKj
setPageSize(PAGESIZE); ^x/D8M
setTotalCount(totalCount); })kx#_o]'d
setItems(items); 1ljcbD)T;
setStartIndex(startIndex); _-#o[>2[
} MQcIH2
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public PaginationSupport(List items, int {*g{9`
lb*;Z7fx<'
totalCount, int pageSize, int startIndex){ ">h$(WCK
setPageSize(pageSize); 0*kS\R=P
setTotalCount(totalCount); `'P&={p8
setItems(items); (nBh6u*
setStartIndex(startIndex); -$#2?/uqC
} 4bdCbI
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publicList getItems(){ ~#VDJ[Z
return items; P*}aeu&lnD
} khT[
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publicvoid setItems(List items){ #u+qV!4
this.items = items; s:_j,/H0A}
} xQzW6H|
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publicint getPageSize(){ %|:j=/_
return pageSize; ,CPAS}kS
} *qLk'<
mea}
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publicvoid setPageSize(int pageSize){ ,afO\oe>MG
this.pageSize = pageSize; @ZJ}lED3
} /zQx}U)TP
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publicint getTotalCount(){ Jy"\_Vvl
return totalCount; 20haA0s
} |%#NA!e4wA
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publicvoid setTotalCount(int totalCount){ =TzJgx
if(totalCount > 0){ {(asy}a9K
this.totalCount = totalCount; #j+cl'
int count = totalCount / .!lLj1?p
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pageSize; aR@+Qf
if(totalCount % pageSize > 0) <-G3Qgm
count++; S1~K.<B
indexes = newint[count]; VG$;ri>
for(int i = 0; i < count; i++){ z%JN| 5
indexes = pageSize * p/7'r
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i; uTJ z"c`F
} eLgq
)
}else{ XDyo=A]
this.totalCount = 0; v_v>gPl,
} &
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} X&rsWk
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publicint[] getIndexes(){ N'l2$8
return indexes; (]&B'1b
} Rg46V-"d,@
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publicvoid setIndexes(int[] indexes){ 9`VY)"rJ
this.indexes = indexes; :9x]5;ma
} aTvLQ@MQ
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publicint getStartIndex(){ 9jx>&MnWs
return startIndex; 9&C8c\Y
} S5Pn6'w
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publicvoid setStartIndex(int startIndex){ g`.H)36
if(totalCount <= 0) q&NXF(
this.startIndex = 0; {-]K!tWda
elseif(startIndex >= totalCount) H,GnF
this.startIndex = indexes !Z{7X ^
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[indexes.length - 1]; *u,xBC2C
elseif(startIndex < 0) k,<7)-
this.startIndex = 0; ]-a/)8
else{ cG@Wo8+
this.startIndex = indexes kJNg>SN*@#
ni )G
[startIndex / pageSize]; C{G=Y[?oc
} -{z[.v.p
} 'IVC!uL,%
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publicint getNextIndex(){ k.)YFKi
int nextIndex = getStartIndex() + '0_W<lGB
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pageSize; [ z/G
if(nextIndex >= totalCount) Eg2jexl
return getStartIndex(); z-"P raP
else v"%>ms"n
return nextIndex; r9b(d]
} Q[H4l({E
s,/C^E
publicint getPreviousIndex(){ O ]-8 %
int previousIndex = getStartIndex() - K *1]P ar;
4"iI3y~Gw
pageSize; K)Z~ iBRM
if(previousIndex < 0) At[SkG}b
return0; 9o P
else "qZTgCOY2
return previousIndex; FLkZZ\
} I.~=\%Z{
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} b`DPlQHj
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抽象业务类 + ~,q"6
java代码: gOE?
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/** 1sJz`+\
* Created on 2005-7-12 E6T=lwOZ
*/ 2pSp(@N3
package com.javaeye.common.business; VtU2&
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import java.io.Serializable; P-yVc2YH
import java.util.List; C+t|fSJ
d}Y#l}!E6
import org.hibernate.Criteria; sE{5&aCSR
import org.hibernate.HibernateException; n3eWqwQ$5
import org.hibernate.Session; Y[rCF=ZVH
import org.hibernate.criterion.DetachedCriteria; od,,2pwK+
import org.hibernate.criterion.Projections; ! z5c+JqN
import ,LLx&jS
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org.springframework.orm.hibernate3.HibernateCallback; =W"T=p*j
import Hxc>?
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org.springframework.orm.hibernate3.support.HibernateDaoS wk^$DM/KJ)
\]S)PDqR
upport; c3<H272\
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import com.javaeye.common.util.PaginationSupport; [IHG9Xg
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public abstract class AbstractManager extends ~Xr[d07bC
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HibernateDaoSupport { >,)U46
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privateboolean cacheQueries = false; o62GEl25
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privateString queryCacheRegion; "s`#`'
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publicvoid setCacheQueries(boolean ox";%|PP1
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cacheQueries){ ~0Zy$L/D
this.cacheQueries = cacheQueries; N!\1O,
} EVLDP\w{
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publicvoid setQueryCacheRegion(String R.GDCGAL
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queryCacheRegion){ p"*xyex
this.queryCacheRegion = cb. -AlqQ
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queryCacheRegion; lm +s5}*%o
} )!
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publicvoid save(finalObject entity){ 6]HMhv
getHibernateTemplate().save(entity); 4T){z^"
} 7kMO);pO
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publicvoid persist(finalObject entity){ X@A8~kj1
getHibernateTemplate().save(entity); O[|X=ZwR:l
} HA&hu/mw_
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publicvoid update(finalObject entity){ =#{q#COK$
getHibernateTemplate().update(entity); :#N]s
} T/hz23nH
#.,LWL]
publicvoid delete(finalObject entity){ q+?q[:nR-
getHibernateTemplate().delete(entity); Y%zWaH
} I}}>M#
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publicObject load(finalClass entity, 5OAb6k'
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finalSerializable id){ ZlcEeG
return getHibernateTemplate().load dtV7YPz4+
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(entity, id); 25W #mh,'
} 2';{o=TXV
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publicObject get(finalClass entity, ]x'd0GH"]
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finalSerializable id){ rfh`;G5s
return getHibernateTemplate().get JM*!(\Y
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(entity, id); $B]_^
} }+)q/]%
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publicList findAll(finalClass entity){ |`AJP
return getHibernateTemplate().find("from =&: |a$C
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" + entity.getName()); N{a=CaYi+
} :{KpnJvd
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publicList findByNamedQuery(finalString F$YT4414
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namedQuery){ O6\c1ha
return getHibernateTemplate A":cS }Ui
v*OT[l7
().findByNamedQuery(namedQuery); vI"BNC*Q1
} }YU\}T-P
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publicList findByNamedQuery(finalString query, Y44[2 :m
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finalObject parameter){ +'[/eW
return getHibernateTemplate F84<='K
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().findByNamedQuery(query, parameter); {]4Zpev
} OgzKX>N`A
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publicList findByNamedQuery(finalString query, Xhpcu1nA
B @8lD\
finalObject[] parameters){ c+##!_[9
return getHibernateTemplate PJ<9T3Fa
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().findByNamedQuery(query, parameters); *}>)E]O@
} |Rm_8n%m
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publicList find(finalString query){ 5YgT*}L+,
return getHibernateTemplate().find Z dT-
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(query); :8A@4vMS)?
} {WTy/$ Qk
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publicList find(finalString query, finalObject 79+i4(H
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parameter){ .OlPVMFt
return getHibernateTemplate().find 1%";|
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(query, parameter); wVF
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} LMLrH.
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public PaginationSupport findPageByCriteria u Vo"_c w
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(final DetachedCriteria detachedCriteria){ ?kF?
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return findPageByCriteria *rYPjk6g[
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); [|\#cVWs
} z0|-OCmL
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public PaginationSupport findPageByCriteria {f;DhB-jj
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(final DetachedCriteria detachedCriteria, finalint m;ju@5X
R_ )PbFw
startIndex){ m!3D5z]n9
return findPageByCriteria bicbCC6kC
'oUTY *
(detachedCriteria, PaginationSupport.PAGESIZE, I
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startIndex); f @Vd'k<
} 2dDhO
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public PaginationSupport findPageByCriteria @c).&7
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(final DetachedCriteria detachedCriteria, finalint x4v&%d=M
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pageSize, |*l^<= =
finalint startIndex){ ~m[Gp;pL
return(PaginationSupport) 1yFIIj:^|
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getHibernateTemplate().execute(new HibernateCallback(){ g`)0
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publicObject doInHibernate n"@){:{4?
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(Session session)throws HibernateException { & u6ydN1xe
Criteria criteria = 9I''$DVf
7R,;/3wWjG
detachedCriteria.getExecutableCriteria(session); Uz%ynH
int totalCount = Zu94dFP
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((Integer) criteria.setProjection(Projections.rowCount 35:RsL
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()).uniqueResult()).intValue(); d?V/V'T[
criteria.setProjection ^UFNds'q
{~XAg~
(null); VLoRS)
List items = $UpWlYwG
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criteria.setFirstResult(startIndex).setMaxResults 0IBQE
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(pageSize).list(); v@{VQVx
PaginationSupport ps = e7plL^^`
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new PaginationSupport(items, totalCount, pageSize, DQ c pIV
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startIndex); D$E#:[
return ps; FU;a
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} "Jdi>{o8
}, true); 8/;@4^Ux
} hBhbcWD,ka
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public List findAllByCriteria(final uI^E9r/hB
Cvr?%+)$M
DetachedCriteria detachedCriteria){ q$Z.5EN
return(List) getHibernateTemplate 2XubM+6
x,a(O@
().execute(new HibernateCallback(){ 2B{~"<
publicObject doInHibernate tY^ MP5*
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(Session session)throws HibernateException { L$^ya%2
Criteria criteria = 7RQ.oee
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detachedCriteria.getExecutableCriteria(session); e$M \HPc
return criteria.list(); ORhe?E]
} ?+)O4?#
}, true); c0.i
} fJ_d,4
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public int getCountByCriteria(final 48JD >=@7
^| L@f
DetachedCriteria detachedCriteria){ GE]cH6E
Integer count = (Integer) fX=o,=-f
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getHibernateTemplate().execute(new HibernateCallback(){ !sA[A>
publicObject doInHibernate Gj[`r
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(Session session)throws HibernateException { bLyU;
Criteria criteria = e)kN%JqW
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detachedCriteria.getExecutableCriteria(session); zrWkz3FN
return iO)FZ%?"
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criteria.setProjection(Projections.rowCount 8C1 ' g7A<
RM8p[lfX
()).uniqueResult(); ]03+8#J
} j3`#v3
}, true); G j^J pG
return count.intValue(); eHUr!zH:
} \^O#)&5 V
} ]]~tFdh
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用户在web层构造查询条件detachedCriteria,和可选的 RN(>37B3_
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^
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;fLYO6
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PaginationSupport的实例ps。 R0dIxG%
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ps.getItems()得到已分页好的结果集 UV}\#86!
ps.getIndexes()得到分页索引的数组 &VG|*&M
ps.getTotalCount()得到总结果数 dLb9p"EE#
ps.getStartIndex()当前分页索引 \mRRx#-r%
ps.getNextIndex()下一页索引 n]$50_@
ps.getPreviousIndex()上一页索引 nA:\G":\y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _&!%yW@
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ~Pq(Ta
d~B]s
一下代码重构了。 u~MD?!LV
~ZbEKqni2
我把原本我的做法也提供出来供大家讨论吧: F/c7^
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首先,为了实现分页查询,我封装了一个Page类: !Z+4FwF
java代码: {k.Dy92
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/*Created on 2005-4-14*/ Wez"E2J`
package org.flyware.util.page; ?M'_L']N[
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/** t Dx!m~[
* @author Joa 6")co9
* q:A{@kFq_
*/ a%f?OsY
publicclass Page { 'Oyx
X
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/** imply if the page has previous page */ =Kdd+g!
privateboolean hasPrePage; uYW9kw>$
tEEeek(!
/** imply if the page has next page */ 99Jk<x
k
privateboolean hasNextPage; 4j9
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/** the number of every page */ -&87nR(eW
privateint everyPage; VT.BHZ
^<L;"jl%
/** the total page number */ 1o5DQ'~n
privateint totalPage; 6n9;t\'Gt
{4u8~whLp
/** the number of current page */ e~7h8?\.q
privateint currentPage; {)^P_zha[9
DtBIDU]
/** the begin index of the records by the current }q0lbwYlb
f@@2@#
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query */ ('1k%`R%
privateint beginIndex; Efo,5
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/** The default constructor */ )3O0:]<H
public Page(){ Y XC?q
2?; =TJo$
} HA}pr6Z
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/** construct the page by everyPage rTJv>Jjld
* @param everyPage q3.L6M
* */ ,BuN]9#
public Page(int everyPage){ 7 ky$9+~
this.everyPage = everyPage; d~[^D<5,D
} Y,1sNg
FS.z lk\D=
/** The whole constructor */ _;*|"e@^
public Page(boolean hasPrePage, boolean hasNextPage, =}@m$g
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z!09vDB^
int everyPage, int totalPage, '8g/^Y@
int currentPage, int beginIndex){ 79J@`
this.hasPrePage = hasPrePage; s(yV E
this.hasNextPage = hasNextPage; LM_/:
this.everyPage = everyPage; Pw4j?pv2
this.totalPage = totalPage; %,9iY&;U"
this.currentPage = currentPage; *|c*/7]<
this.beginIndex = beginIndex; mPR(4Ol.
} t
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k
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/** 7h?yAgDv~
* @return p{:r4!*L
* Returns the beginIndex. U].u) g$
*/ j[/'`1tOe
publicint getBeginIndex(){ \-c8/=
return beginIndex; $mA+4ISK
}
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/** q9n0bw^N
* @param beginIndex 51oZw%os=
* The beginIndex to set. Q
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*/ Ed/@&52z0
publicvoid setBeginIndex(int beginIndex){ {b@rQCre7
this.beginIndex = beginIndex; amI$0
} &lYKi3}x
],r?]>
/** rQNT
* @return _`!@
* Returns the currentPage. Y=3:Q%X
*/ "4FL<6
publicint getCurrentPage(){ &k3'UN!&Ix
return currentPage; Qi^MfHW
} Vy
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/** fTi,S)F'
* @param currentPage Xq&x<td
* The currentPage to set. }z&P^p)R
*/ 8uME6]m
i
publicvoid setCurrentPage(int currentPage){ @URLFMFi
this.currentPage = currentPage; nbYkr*: "t
} H3 _7a 9
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/** an3HKfv
* @return T6f{'.w
* Returns the everyPage. 6Rn_@_Nn)f
*/ $;*YdZ`q
publicint getEveryPage(){ l79jd%/m
return everyPage; n<:/ X tE
} #)%N+Odnr
;%
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/** 8|[\Tp:;
* @param everyPage z;x`dOP
* The everyPage to set. amf=uysr
*/ 5Ah-aDBj
publicvoid setEveryPage(int everyPage){
mQ#@"9l%
this.everyPage = everyPage; 3nBbPP_
} ww"ihUX
*qg9~/
/** /qF7^9LtaY
* @return O?@1</r^
* Returns the hasNextPage. {xt<`_R
*/ yy?|q0
publicboolean getHasNextPage(){ ]
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return hasNextPage; ?Gl'-tV
} I=hgfo
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/** 8QYG"CA6/
* @param hasNextPage 7|6tH@4Ub
* The hasNextPage to set. w_^&X;0^
*/ _u}v(!PI
publicvoid setHasNextPage(boolean hasNextPage){ L{2\NJ"+u
this.hasNextPage = hasNextPage; !?tWWU%P)
} /#$bb4
!U]V?Jpi"
/** $XFG1?L!
* @return 49
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* Returns the hasPrePage. u0$7k9mE
*/ [p@NzS/
publicboolean getHasPrePage(){ 4:cbasy
return hasPrePage; mU_?}}aK,
} M@Q=!!tQ(
CzzG
/** +nd'Uf
* @param hasPrePage lf|e8kU\f
* The hasPrePage to set. U6X~]| o
*/ 'KQ]7
publicvoid setHasPrePage(boolean hasPrePage){ W<2%J)N<
this.hasPrePage = hasPrePage; uYL6g:]+ZC
} )F? 57eh
LF%1)x
/** (W+9 u0Zq
* @return Returns the totalPage. `ea$`2
* !U>"H8}dv
*/ 1s\10 hK1c
publicint getTotalPage(){ W _b$E
=
return totalPage; ( uOW5,e7
} O)Nt"k7
b
}p t5. 'l
/** 8)rv.'A((E
* @param totalPage (Wq9YDD@
* The totalPage to set. joDfvY*[
*/ K@n.$g
publicvoid setTotalPage(int totalPage){ NOx&`OU+
this.totalPage = totalPage; /BT;Q)(&
} kRiWNEw
}(E6:h;}~
} T<54qe4`p
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e%bERds
CR934TE+
(%#d._j>fZ
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 |@nvg>mu
e+y< a~N
个PageUtil,负责对Page对象进行构造: 4Bx1L+Cg
java代码: Z(K [oUJx
NH'RU`U)
@hzQk~Gdi
/*Created on 2005-4-14*/
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package org.flyware.util.page; 'VJMi5Y(-
gn%#2:=pVu
import org.apache.commons.logging.Log; (dMFYL>YP
import org.apache.commons.logging.LogFactory; {]<D"x;
GJO/']k
/** 8.pz?{**T
* @author Joa 3jS=
* <Dm6CH
*/ + {hxEDz
publicclass PageUtil { y^@%Xrs
|~\K:[T&
privatestaticfinal Log logger = LogFactory.getLog !a~x|pjJ
4
>&%-BhN
(PageUtil.class); K+v 250J$-
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/** iLmU|jdE
* Use the origin page to create a new page jLQjv
* @param page e_1mO 5z
* @param totalRecords 1
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* @return n[4Nu`E9
*/ @O45s\4-*
publicstatic Page createPage(Page page, int \=N
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totalRecords){ J $e.$ah;
return createPage(page.getEveryPage(), K,IOD
t
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page.getCurrentPage(), totalRecords); !5B9:p~-
} G4x.''r&Sl
Z;>~<#!4
/** J`RNik*>
* the basic page utils not including exception b,Z&P|
='VIbE@qC
handler t*qA.xc6
* @param everyPage `n5c|`6
* @param currentPage E<\\ 'VF
* @param totalRecords *<Ddn&_
* @return page oVq@M
*/ \B}W(^\wg;
publicstatic Page createPage(int everyPage, int c<DYk f
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currentPage, int totalRecords){ k oHY
AF
everyPage = getEveryPage(everyPage); @\"*Z&]8z0
currentPage = getCurrentPage(currentPage); c hd${
j
int beginIndex = getBeginIndex(everyPage, }MIH{CMH
>}4]51s
currentPage); ) F~>
int totalPage = getTotalPage(everyPage, [CUJ A
c%Gz{':+
totalRecords); zr[~wM
boolean hasNextPage = hasNextPage(currentPage, 19N:9;Ixz
xJ"Zg]d{
totalPage); 1)YFEU&]
boolean hasPrePage = hasPrePage(currentPage); J:(Shd'4D
8^R>y
returnnew Page(hasPrePage, hasNextPage, lwY{rWo
everyPage, totalPage, KPR{5
currentPage, *z+\yfOO"
D{loX6
beginIndex); f%|S>(
} }oN(nPxv9
j2P|cBXu
privatestaticint getEveryPage(int everyPage){ +%<Jr<~W
return everyPage == 0 ? 10 : everyPage; ;9I#>u
} v
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J<BdIKCma
privatestaticint getCurrentPage(int currentPage){ \
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return currentPage == 0 ? 1 : currentPage; 4O`h%`M
} mCE})S
Dq?2mXOqD
privatestaticint getBeginIndex(int everyPage, int 7q^/.:wlf
Z~c7r n
currentPage){ ^=W&p%Y(!
return(currentPage - 1) * everyPage; b?Jm)
} Z|/):nVP7
?Tl@e
privatestaticint getTotalPage(int everyPage, int xw-q)u
&*yve}su
totalRecords){ }fCM_w
int totalPage = 0; 5rWRE-
)m'_>-`^:
if(totalRecords % everyPage == 0) P\AH9#XL
totalPage = totalRecords / everyPage; UF%5/SiVX
else ..T(9]h
totalPage = totalRecords / everyPage + 1 ; |X.z|wKT6
q#a21~S<
return totalPage; ,9pi9\S
} f2u2Ns0Ym
\\lC"Z#J`
privatestaticboolean hasPrePage(int currentPage){ *Vc=]Z2G^
return currentPage == 1 ? false : true; Kje+Niz7
} -J30g\
\k,bz0
privatestaticboolean hasNextPage(int currentPage, M/DTD98'N
9F+bWo_m
int totalPage){ >ahj|pm
return currentPage == totalPage || totalPage == j41:]6
i\Vpp8<B
0 ? false : true; oTfbx+i/G
}
KC(Ug4
UQR"wUiiV
UZ!hk*PF
} :L[6a>"neE
vjb?N
m#ie{u^
Imwx~eo
8`t%QhE2
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。
++CL0S$e
u4~(0
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 t_iZ\_8
W C3b_ia
做法如下: sx][X itR+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /i
IWt\J
*Edr\P
的信息,和一个结果集List: 9S{?@*V
java代码: z1LY|8$G
7J$Yd976
<Q?_],ip
/*Created on 2005-6-13*/ 8zH/a
package com.adt.bo; UpqDGd7M
{ud^+I&
import java.util.List; 2"B3Q:0he|
?v Z5 ^k
import org.flyware.util.page.Page; 4.'KT;[_1/
B=hJ*;:p
/** !gG\jC~n
* @author Joa G2hBJTW
*/ ~f[91m!+
publicclass Result { )q'~<QxI\
uH8`ipX
private Page page; .iH#8Z
YbE1yOJ&m
private List content; J!*Pg<
Zq>}SR
/** BXX1G
* The default constructor Wg5i#6y8w
*/ o/p'eY:)
public Result(){ uT{.\qHo
super(); -u%'u~s
} P8;f^3V(+/
ot.R Gpg%
/** :]-? l4(%
* The constructor using fields AV?<D.<
* }S>:!9f
* @param page z,/y2H2
* @param content OvW/{
*/ My\
public Result(Page page, List content){ V39)[FH}
this.page = page; ^1NtvQe@Y\
this.content = content; |cq%eN
} 0Z>oiBr4
~*uxKEH
/** 9{5 c}bX
* @return Returns the content. /pDI
\]
*/ 1~ZKpvu
publicList getContent(){ ^9I^A!w=
return content; _\2^s&iJh
} o*1t)HL <
&-6D'@
/** k0R;1lZ0n
* @return Returns the page. 1">]w2je:
*/ m1lfC
public Page getPage(){ YP vg(T
return page; Y&_1U/}h
} 9=Rj9%
h\^> s$
/** JPT VZ
* @param content AAt<{
* The content to set. 1MzOHE
*/ me`(J y<
public void setContent(List content){ WS)u{
or
this.content = content; i iZK^/P$
} J#y?^Qm$)<
ps6c>AN`A&
/** u3H2\<
* @param page `?L-{VtM3*
* The page to set. VClw!bm
*/ SAGLLk07G
publicvoid setPage(Page page){ 8M;G@ Q80
this.page = page; |_;Vb
} D;Jb'Be
} Zm@
O[:~
_A.?:'-
U"v}br-kb
c=p @l<)
W[3)B(Vq<E
2. 编写业务逻辑接口,并实现它(UserManager, 4r [Tpb
<ST#<
$%
UserManagerImpl) k&P_ c
java代码: p
}bTI5
fE/8;v!=
-j_J1P0,
/*Created on 2005-7-15*/ :B'}#;8_
package com.adt.service; :{tvAdMl7
l<$c.GgFd
import net.sf.hibernate.HibernateException; V ;)q?ZHg
:22IY>p
import org.flyware.util.page.Page; w{"GA~=
1H_#5hd
import com.adt.bo.Result; M_4g%uHG
PaFJw5f
/** z,oqYU\:
* @author Joa wQ,RZO3
*/ 8D:{05
publicinterface UserManager { 5yQv(<~*G
, &HZvU&
public Result listUser(Page page)throws 0ZV)Y<DJ
[@= [<
_r
HibernateException; r\"O8\
$0Y&r]'
} `8TM<az-L
$E4W{ad2jW
K,}"v ;||
sHrpBm&O4
R6Cm:4m}I
java代码: Tf"DpA!_
[,a O*7N
wDZFOx0#8
/*Created on 2005-7-15*/ DwZt.*
package com.adt.service.impl; q$`:/ ehw
LxVd7r VY6
import java.util.List; ?Y'S
/
u
hP0Zwn
import net.sf.hibernate.HibernateException; O`dob&C
lq_W;L
import org.flyware.util.page.Page; dTaR8i
import org.flyware.util.page.PageUtil; j78xMGKO
h& (@gU`A
import com.adt.bo.Result; 2`vCQV
import com.adt.dao.UserDAO; Q[p0bD:
import com.adt.exception.ObjectNotFoundException; C<fNIc~.
import com.adt.service.UserManager; )B*?se]LJ
?4Z0)%6
/** @WU_GQas3
* @author Joa @U:T}5)wc
*/ ZZE
publicclass UserManagerImpl implements UserManager { Vrz!.X~
g#_?Vxt
private UserDAO userDAO; u6y\ GsM.a
5!Z+2Cu]
/** _:'m/K3Ee
* @param userDAO The userDAO to set. p^YE"2 -
*/ =O)JPo&iwY
publicvoid setUserDAO(UserDAO userDAO){ ok\+$+$ju
this.userDAO = userDAO; G"TPu_g
} _u;^w}0
q 'hV 'U
/* (non-Javadoc) <'~8mV1
* @see com.adt.service.UserManager#listUser vtmO
d!KX.K\NM,
(org.flyware.util.page.Page) Bd O$
*/ &J hN&Ur
public Result listUser(Page page)throws vo`wYJ3W
fsjA7)/
HibernateException, ObjectNotFoundException { d=qpTb;(
int totalRecords = userDAO.getUserCount(); e^Xij Id.
if(totalRecords == 0) AD?DIE(v
throw new ObjectNotFoundException #4//2N
g@Ni!U"_c
("userNotExist"); 4Ro(r
sO
page = PageUtil.createPage(page, totalRecords); BQS9q'u_
List users = userDAO.getUserByPage(page); I I>2\d|
returnnew Result(page, users); sjTsaM;<
} $xu?zd"
F41!Dj7
} ;mi0Q.
_;B!6cRLps
N@MeaO
GPR`=]n& &
3^Yk?kFE
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 E;4Ns
2hJ{+E.m
询,接下来编写UserDAO的代码: M+hc,;6
3. UserDAO 和 UserDAOImpl: ]Hd0
Y%
java代码: 50DPzn
NNl/'ge<\
M@'V4oUz
/*Created on 2005-7-15*/ %&_(IY$d
package com.adt.dao; WQ5sC[&
^Nsl5
import java.util.List; @5?T]V g
i9!Urq-
import org.flyware.util.page.Page; H;sQ]:.*]
R^B2J+O
import net.sf.hibernate.HibernateException; =(n'#mV
3K?0PRg
/** mzT} C&hfP
* @author Joa AVyZ#`,
*/ MW`a>'0t?
publicinterface UserDAO extends BaseDAO { 7 $9fGo
D`t e|K5
publicList getUserByName(String name)throws rmMO-!s
Yip9K[
HibernateException; pz&=5F
jujx3rnK?
publicint getUserCount()throws HibernateException; D} .t
xeI ,Kz."
publicList getUserByPage(Page page)throws ,K9UT#h
34oLl#q*
HibernateException; <Y orQ>
44W3U~1
} KFZ[gqW8YY
T?\CAk>
Q"Ec7C5eM
y2 +a2
=O;SXzgE
java代码: jVA~]a
'd t}i<
Y;Ur8q
/*Created on 2005-7-15*/ M)J *Df0@
package com.adt.dao.impl; ^TEODKS
\W}EyA
import java.util.List; lTB!yF.r|
Pj.~|5gnf
import org.flyware.util.page.Page; ,#E5 /'c`
oba*w;
import net.sf.hibernate.HibernateException; jO,<7FPs5
import net.sf.hibernate.Query; aydal9M
WD\{Sdx:r
import com.adt.dao.UserDAO; 0wkLM-lN
Qi[D&47XO
/** t<|s&
* @author Joa og\XLJ}_
*/ gPwp
[
public class UserDAOImpl extends BaseDAOHibernateImpl v)d0MxSC
<=inogf
implements UserDAO { o 4b{>x
DrEtnt
/* (non-Javadoc) r{Q< a
* @see com.adt.dao.UserDAO#getUserByName V^{!d}
ZWa#}VS}-n
(java.lang.String) OV/FQH;V
*/ )j6>b-H
publicList getUserByName(String name)throws bvgD;:Aj
2Y4&Sba^Y
HibernateException { W<LaR,7
String querySentence = "FROM user in class >ek%P;2w>
od}x7RI%m
com.adt.po.User WHERE user.name=:name"; 2wBU@T1
Query query = getSession().createQuery w+37'vQ
yo.SPd="Vx
(querySentence); "<2bjy
query.setParameter("name", name); {T.Vu]L80
return query.list(); ->hxHr`!%a
} z`5I1#PVA
DXz8C -
/* (non-Javadoc) e1loI8
* @see com.adt.dao.UserDAO#getUserCount() BP[U`
!
*/ .V3Dql@z"
publicint getUserCount()throws HibernateException { be/1-=m
int count = 0; n`}&,UA$4
String querySentence = "SELECT count(*) FROM N 9&@,3
:b;1P@W<
user in class com.adt.po.User"; BZ<z@DJp
Query query = getSession().createQuery GzXP
"J5Pwvs-
(querySentence); GF!{SO4
count = ((Integer)query.iterate().next GnOo+hB
v,+l xY
()).intValue(); V
3]p3
return count; WHZng QmY
} ^.C X6%
'r n;|K
/* (non-Javadoc) j_yFH#^W:
* @see com.adt.dao.UserDAO#getUserByPage w)eQ'6Vu
)t0b$<%
(org.flyware.util.page.Page) Ql@yN@V
*/ %9/)
publicList getUserByPage(Page page)throws {@ y,
^R7z LHU;
HibernateException { _<a)\UR
String querySentence = "FROM user in class j$|C/E5?
r65NKiQD
com.adt.po.User"; 3Gl]g/
Query query = getSession().createQuery =+h!JgY/L
rgzI
(querySentence); dO4#BDn"=
query.setFirstResult(page.getBeginIndex()) ]0i2]=J&,
.setMaxResults(page.getEveryPage()); (1,#=e+
return query.list(); IA`8ie+
} 87(^P3;@
;]M67ma7C
} 'D"K`Vw
R[9PFMn
]XGn2U\
9BD|uU;0
m90R8 V
至此,一个完整的分页程序完成。前台的只需要调用 .XKvk(9
PBs<8xBx^
userManager.listUser(page)即可得到一个Page对象和结果集对象 g**%J Xo
m=.7f9
的综合体,而传入的参数page对象则可以由前台传入,如果用 OEE{JVeI
`VFl|o#H
webwork,甚至可以直接在配置文件中指定。 ZU.)K>'
:ZfUjqRE
下面给出一个webwork调用示例: f5b`gvCY,#
java代码: pd>a6 lI`
Mto~ /
!$xEX,vj|W
/*Created on 2005-6-17*/ N^yO- xk
package com.adt.action.user; wwcwYPeg
a^T4\
import java.util.List; \Tf{ui
UeQ9G
import org.apache.commons.logging.Log; D'[P,v;Q
import org.apache.commons.logging.LogFactory; Df,VV+
import org.flyware.util.page.Page; 9;Pu9s[q2
V=4u7!ha
import com.adt.bo.Result; #Wm@&|U
import com.adt.service.UserService; ROt0<^<
import com.opensymphony.xwork.Action; vx5o
k1UY
tbzvO<~
/** q\b
?o!#_
* @author Joa ,o>pmaoLs
*/ eN<pU%7
publicclass ListUser implementsAction{ \m~\,em
v6P~XK}G
privatestaticfinal Log logger = LogFactory.getLog R`C_CsXir
"">fn(
(ListUser.class); %cr]ZR
PDq}Tq
private UserService userService; 8P<UO
9MtJo.A
private Page page; /IJ9_To
88np/jvC{
privateList users;
)47j8jL
=7]Q6h@X
/* ilRm}lU|x
* (non-Javadoc) %QsSR'`
* .xz,pn}
* @see com.opensymphony.xwork.Action#execute() +z jzO]8
*/ >_0 i=.\
publicString execute()throwsException{ Q"6hD?6.
Result result = userService.listUser(page); e7bT%h9i
page = result.getPage(); &Rl3y\
r
users = result.getContent(); af?\kBm
return SUCCESS; @Wx`l) b
} ^8-~@01.`_
k|$"TFXx;
/** }u3H4S<o
* @return Returns the page. L >Ez-
*/ "'}v 0*[
public Page getPage(){ f0mH|tI`
return page;
+ptF -
} ;+ Co!L
ycl>git]
/** "\zj][sL
* @return Returns the users. _Xk03\n6
*/ orQV'
publicList getUsers(){ 17n+4J]
return users; V^Mf4!A(y
} wKi}@|0[@
}KD7 Y
/** 6&
&} P79
* @param page Pi"~/MGP$
* The page to set. iFwyh`Bcg
*/ EBIa%,
publicvoid setPage(Page page){ vNK`Y|u@
this.page = page; ezg^5o;
} p'Y&Z?8
(ifqwl62
/** (N*<\6kr
* @param users qr'x0r|<>
* The users to set. \C+*loLs
*/ aJy>
publicvoid setUsers(List users){ 38w.sceaT
this.users = users; C)J_lI{^
} s0\f9D
n{.*El>{
/** W?"2;](
* @param userService kyRh k\X
* The userService to set. %0+h
*/ <=)D=Ax/_[
publicvoid setUserService(UserService userService){ 3XAp Y'
this.userService = userService; \tiUEE|k
} g:uvoMUD
} a+YR5*&[OO
4]DAh
z\Pe{J
.# !'c
Nl$gU3kL
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, hs!UX=x|
(c(-E|u.
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 )KaLSL>
wVvqw/j*f
么只需要: P7'oXtW{o
java代码: KrdZEi vb
}@rg5$W
9S:{
<?xml version="1.0"?> v+!y;N;Q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fCt^FU
[)Z'N/;0
1.0//EN" "http://www.opensymphony.com/xwork/xwork- '!j #X_;
6?1s`{yy
1.0.dtd"> l)tTg+:
9*}iBs
<xwork> &\J?[>EJ.
V-D}U$fw
<package name="user" extends="webwork- Sk6b`W7$
;mf4U85
interceptors"> [K/O5_
NCowt|#t
<!-- The default interceptor stack name YVQ_tCC_!
la
G$v-r
--> YBYB OH
<default-interceptor-ref *3A3>Rwu
dWsT Jyx~
name="myDefaultWebStack"/> E^Q@9C<!d
j!zA+hF(
<action name="listUser" g,t3OnxS?
Veb+^&
class="com.adt.action.user.ListUser"> Lv
`#zgo_f
<param 2-vJv+-
,s1&O`
name="page.everyPage">10</param> <^,o$b
<result ${A5-
G0_&gx`
name="success">/user/user_list.jsp</result> -Z:]<;qU
</action> /6+1{p
!cq=)xR
</package> "C_T]%'Wm
!GlnQ`T
</xwork> 5x*5|8
f,Sth7y
ksB
q+YuVQ-fx
RL?u n}Qa
i0k+l
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 1vB-M6(
<lC]>L
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 j y7
DRH'A!r!
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 U8CWz!;Qz
HG2N-<$
./5jx2V
BX@pt;$ek7
q:vz?G
我写的一个用于分页的类,用了泛型了,hoho 4rI:1yGt@
J&A;#<qY
java代码: lkV6qIj
jr9&.8%W:v
,`;jvY~Ec
package com.intokr.util; HbNYP/MN3
Y.q>EUSH
import java.util.List; NA+&jV
J#0GlK@"
/** GtF2@\
* 用于分页的类<br> /@Ez" ?V2
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pJd 0k"{
*
#;d)?
* @version 0.01 =K .r
* @author cheng Y5HfN[u^7
*/ 3=Z<wD s
public class Paginator<E> { Am=wEu[b
privateint count = 0; // 总记录数 Ejq=*UOP
privateint p = 1; // 页编号 lY.B
privateint num = 20; // 每页的记录数 4RhR[
privateList<E> results = null; // 结果 'V&2Xvl%
wa" uFW
/** O7v]p
* 结果总数 DR6]-j!FK
*/ -n$ewV
publicint getCount(){ VMx%1^/(
return count; ~wTX>qV
} Kh)FyV
`|]e6Pb
publicvoid setCount(int count){ cS}r9gaQ
this.count = count; vXb:
} :lK4
db
" \:ced
/** DF'8GF&Rp
* 本结果所在的页码,从1开始 uArR\k(
* ^/*KNnAWp
* @return Returns the pageNo. H>.B99vp
*/ [fl^1!3{
publicint getP(){ 'bx$}w N
return p; D>m!R[!o
} +X4/l"|
v|#}LQZ
/** oa:30@HSb
* if(p<=0) p=1 ?)mM]2%%
* ?n9?`8a#
* @param p K-,8~8[
*/ IHStN,QD
publicvoid setP(int p){ \8iWcqJktN
if(p <= 0) \%$z!]S>
p = 1; 6rg?0\A<
this.p = p; KQ2jeJ/pj
} +"F 9yb
JVt(!%K}&
/** nWb0S
* 每页记录数量 kzXmiBL<9
*/ 5$Da\?Fpn
publicint getNum(){ q}MPl 2
return num; ]}HuK#
} mrId`<L5l{
6ujePi <U
/** #P5tTCM
* if(num<1) num=1 T Z_](%
*/ 7FvtWE*
publicvoid setNum(int num){ ar[*!:!
if(num < 1) = 6^phZ(
num = 1; t Zqy \_G
this.num = num; fLR\@f
} f]37Xl%I
C">w3#M%
/** zD%@3NA41
* 获得总页数 HL34pmc
*/ CH4 ~9mmE
publicint getPageNum(){ Y!nxHRE
return(count - 1) / num + 1; o<\9OQ0
} gy6Pf4Yo
t-3y`31i.
/** 7qT>wCVT
* 获得本页的开始编号,为 (p-1)*num+1 1:VbbOu->V
*/ z-;2)RkV2
publicint getStart(){ c ]!Yb-
return(p - 1) * num + 1; 0OAHD '
} uSU[Y,'x
RT$.r5l_@
/** M73d^z
* @return Returns the results. x9s1AzM{
*/ YMfjTt@Q
publicList<E> getResults(){ \g<=n&S?
return results; W*/0[|n*
} J8:f9a:|M
M8}t`q[-&
public void setResults(List<E> results){ f_qW+fN::s
this.results = results; +`s%-}-r
} QGM@m:O
P_8z'pYd>
public String toString(){ $2lPUQZ<5
StringBuilder buff = new StringBuilder Tye[iJ
5^7q
2".
(); l-G] jXu
buff.append("{"); #I] ^Wo
buff.append("count:").append(count); -`<