Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 RBA{!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :L6,=#
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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 !W4X4@
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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 q-3e^-S*
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分页支持类: Ec/-f`8
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java代码: oIJ.Tv@N(
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package com.javaeye.common.util; wn&5Ul9Elb
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import java.util.List; a3Fe42G2c|
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publicclass PaginationSupport { }#Q?\
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publicfinalstaticint PAGESIZE = 30; 8rNRQOXOa
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privateint pageSize = PAGESIZE; {SOy-
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privateList items; m~<<ok_
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privateint totalCount; 1UwpLd
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privateint[] indexes = newint[0]; 8wX|hK!Gz
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privateint startIndex = 0; RHIGNzSz
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public PaginationSupport(List items, int ~snYf7
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totalCount){ :rdnb=n
setPageSize(PAGESIZE); }R\;htmc;
setTotalCount(totalCount); \Q~HL_fy|Y
setItems(items); LPRvzlY=
setStartIndex(0); R/|2s
} BM+>.
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public PaginationSupport(List items, int i\yp(tE%^
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totalCount, int startIndex){ @@QB,VS;{<
setPageSize(PAGESIZE); ol #4AU`
setTotalCount(totalCount); so]p1@K
setItems(items); RX cfd-us
setStartIndex(startIndex); 9N*!C{VW
} X[;-SXq
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public PaginationSupport(List items, int +)06*"I
./r#\X)dc
totalCount, int pageSize, int startIndex){ 8IQqDEY^
setPageSize(pageSize); -NL=^O$G
setTotalCount(totalCount); y/\0qQ/
setItems(items); enB2-)<K
setStartIndex(startIndex); 2$=I+8IL
} 6jpfo'uB$
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publicList getItems(){ .{t]Mc
return items; '1NZSiv+C?
} ~]S%b3>
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publicvoid setItems(List items){ s^lm
81;
this.items = items; ^a #
} U_oei3QP
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publicint getPageSize(){ k>W}9^ cK
return pageSize; & Do|Hw
} #}8 x
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publicvoid setPageSize(int pageSize){ KpF/g[m
this.pageSize = pageSize; z.6I6IfL\L
} j@778fvM\t
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publicint getTotalCount(){ j#D (
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return totalCount; r(i!". Z
} ?'%9
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publicvoid setTotalCount(int totalCount){ f`Wces=5
if(totalCount > 0){ YLkdT%
this.totalCount = totalCount; y|h:{<
int count = totalCount / vIpitbFC
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pageSize; {+@M!
if(totalCount % pageSize > 0) &|#z" E^-
count++; 34s>hm=0.
indexes = newint[count]; d.:.f_|
for(int i = 0; i < count; i++){ hY}.2
indexes = pageSize * a&)4Dv0
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i; Y. 1dk
} ^^+vt8|
}else{ sA1 XtO<&7
this.totalCount = 0; 2 i:tPe&
} ]<<+#Rg
} :(Uz`k7
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publicint[] getIndexes(){ o)SA^5
return indexes; p5?8E$VHV
} /}&@1
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publicvoid setIndexes(int[] indexes){ =! P
this.indexes = indexes; :j[a X7Sq2
} c,FhI~>R
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publicint getStartIndex(){ jQRl-[n
return startIndex; NoD\t(@h
} ;{S7bH'6m
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publicvoid setStartIndex(int startIndex){ t#sw{RO
if(totalCount <= 0) ?CHFy2%Y
this.startIndex = 0; (8d"G9R(
elseif(startIndex >= totalCount) J]mq|vE
this.startIndex = indexes |:G`f8q9
|\] _u 3
[indexes.length - 1]; vm4q1!!(
elseif(startIndex < 0) /Zm5fw9
this.startIndex = 0; `@#,5S$ E
else{ q+ )csgN
this.startIndex = indexes UukHz}(E
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[startIndex / pageSize]; \r^*4P,,
} "u.4@^+i
} n&;-rj^qq
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publicint getNextIndex(){ DY' 1#$;
int nextIndex = getStartIndex() + ptvM>zw'~g
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pageSize; VSQxlAGk@
if(nextIndex >= totalCount) /'WVRa
return getStartIndex(); &XH{,fv$
else x39n7+j4
return nextIndex; ;VIW/
} ^ Z~'>J
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publicint getPreviousIndex(){ p&<X&D
int previousIndex = getStartIndex() - &bw
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9G)q U
pageSize; `|d&ta[{
if(previousIndex < 0) o^b4l'&o
return0; .X(*mmH
else b{i7FRR>o4
return previousIndex; nd?R|._R
} +'fdAc:5',
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} ~n$e
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抽象业务类 ?iQA>P9B
java代码: G: p!PB>=
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/** M+q|z0 U
* Created on 2005-7-12 ~.'NG?
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*/ 4zw5?$YWO"
package com.javaeye.common.business; #w<:H1,4
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import java.io.Serializable; tE>hj:p
import java.util.List; KXy|Si8w
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import org.hibernate.Criteria; `fUem,$)1F
import org.hibernate.HibernateException; <D!\"C
import org.hibernate.Session; K;}h
u(*\]
import org.hibernate.criterion.DetachedCriteria; |Y42ZOK0
import org.hibernate.criterion.Projections; #H1ng<QV
import E%E3h1Ua
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org.springframework.orm.hibernate3.HibernateCallback; 5
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import '5vgpmn
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org.springframework.orm.hibernate3.support.HibernateDaoS sG~5O\,E
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upport; Gj}P6V_
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import com.javaeye.common.util.PaginationSupport; Tfba3+V
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public abstract class AbstractManager extends hiN6]jL|O
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HibernateDaoSupport { 9G'Q3?
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privateboolean cacheQueries = false; e2?7>?
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privateString queryCacheRegion; <Hq|<^_K
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publicvoid setCacheQueries(boolean T;u>]"S
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0
cacheQueries){ 8yDu(.Q
this.cacheQueries = cacheQueries; !Xbr7:UPN1
} C$1}c[
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publicvoid setQueryCacheRegion(String XdDy0e4{%<
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queryCacheRegion){ fem>WPvG
this.queryCacheRegion = ~Z'3(n*9
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queryCacheRegion; ?`oCc[hY
} p7A&r:qq#
}"'^.FG^_
publicvoid save(finalObject entity){ yn[^!GuJ_
getHibernateTemplate().save(entity); 'b*
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} hl[!4#b]K
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publicvoid persist(finalObject entity){ ;J[1S
getHibernateTemplate().save(entity); 4oF8F)ASj
} ,ij"&XA
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publicvoid update(finalObject entity){ poqx
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getHibernateTemplate().update(entity); Jz!8Xg%a
} n~#%>C7
9W{=6D86e
publicvoid delete(finalObject entity){ }lk_Oe1
getHibernateTemplate().delete(entity); EEaf/D/ jt
} 2B#
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publicObject load(finalClass entity, C#<:x!
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finalSerializable id){ \I@=EF- &
return getHibernateTemplate().load 5Z 7 <X2
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(entity, id); v[_C^;
} oXc!JZ^
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publicObject get(finalClass entity, Wh:SZa|
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finalSerializable id){ 5_@8g+~
return getHibernateTemplate().get McgTTM;E
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(entity, id); 3+<}Hm+
} !po8[fz~x
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publicList findAll(finalClass entity){ ()Z! u%j
return getHibernateTemplate().find("from /3!KfG
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" + entity.getName()); @N,EoSb :
} gp:,DC?(
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publicList findByNamedQuery(finalString X=Q)R1~6v
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namedQuery){ M ]dS>W%U
return getHibernateTemplate {q%wr*
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().findByNamedQuery(namedQuery); vr|9NP]v
} !_VKJZuH
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publicList findByNamedQuery(finalString query, ngprTMO$&
,%#FK|
finalObject parameter){ YK/?~p9:
return getHibernateTemplate 3[E3]]OVa
u=h:d+rq@
().findByNamedQuery(query, parameter); $ ZD1_sJ.
} nk,X6o9%
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publicList findByNamedQuery(finalString query, }&)X4=
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finalObject[] parameters){ /vi>@a
return getHibernateTemplate )oJn@82C|
K14e"w%6rs
().findByNamedQuery(query, parameters); .(OFYK<
} Gpws_jw
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publicList find(finalString query){ 2r2qZ#I}
return getHibernateTemplate().find 66*/"dBwm
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(query); IWvLt
} .az+'1
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publicList find(finalString query, finalObject .7Zb,r
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parameter){ cF9bSY_Eh
return getHibernateTemplate().find %|$h<~
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(query, parameter); GndU}[0J
} 6eqxwj{S[
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public PaginationSupport findPageByCriteria &v7$*n27
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(final DetachedCriteria detachedCriteria){ :?%$={m
return findPageByCriteria Hn5:*;N
l2"{uCcA
(detachedCriteria, PaginationSupport.PAGESIZE, 0); +jePp_3$O
}
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public PaginationSupport findPageByCriteria =*7K_M&
{<{
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(final DetachedCriteria detachedCriteria, finalint +:3K?G-
ct+ ;W
startIndex){ t{#Btd
return findPageByCriteria FS7 _ldD
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(detachedCriteria, PaginationSupport.PAGESIZE, cRPW
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startIndex); G.Z:00x
} _ KBN
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public PaginationSupport findPageByCriteria @: u>
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(final DetachedCriteria detachedCriteria, finalint T
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pageSize, Q>Rjv.1
finalint startIndex){ m~cz
return(PaginationSupport) qRkY-0vBP
' NyIy:
getHibernateTemplate().execute(new HibernateCallback(){ (- `h8M
publicObject doInHibernate h/E+r:2]
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(Session session)throws HibernateException { EkotVzR5
Criteria criteria = f%fD>a
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detachedCriteria.getExecutableCriteria(session); @v^;,cu'8
int totalCount = -`nQa$N-
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((Integer) criteria.setProjection(Projections.rowCount xj8yQ Y1
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()).uniqueResult()).intValue(); 'B dZN
criteria.setProjection Z<L|WRe
cPD&xVwq>
(null); IE7%u92
List items = }71a3EUK
\ng!qN
criteria.setFirstResult(startIndex).setMaxResults `}t<5_
qxKW%{6o
(pageSize).list(); Y+vG]?D
PaginationSupport ps = q<.m@q
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new PaginationSupport(items, totalCount, pageSize, 72uARF
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startIndex); |>_e&}Y%L
return ps; oYOR%'0*m+
} T1,Nb>gBq^
}, true); m)"gj**|y
} Jbv66)0M
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public List findAllByCriteria(final SU>2MT^
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DetachedCriteria detachedCriteria){ 1dDK(RBbQ
return(List) getHibernateTemplate AA=zDB<N
wq K:=
().execute(new HibernateCallback(){ L@9@3?
publicObject doInHibernate @JB9qT
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(Session session)throws HibernateException { G8bc\]
Criteria criteria = {}gx;v)
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); d$DNiJ ,
} jQ>~
}, true); $K& #R-
} l9Xz,H
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public int getCountByCriteria(final 'M20v-[
{`RCh]W
DetachedCriteria detachedCriteria){ py\KY R
Integer count = (Integer) ]#$l"ss,
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getHibernateTemplate().execute(new HibernateCallback(){ 6:\0=k5
publicObject doInHibernate PB[Y^q
a -[:RJW
(Session session)throws HibernateException { !*I0}I
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Criteria criteria = )gNS%tc*K
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detachedCriteria.getExecutableCriteria(session); dWKjVf
return wE*o1.
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criteria.setProjection(Projections.rowCount 2TQyQ%
MS Qz,nn
()).uniqueResult(); {>EM=ZZfg
} hCpX#rg?
}, true); nDG41)|
return count.intValue(); {$
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} O@9<7@h+Nl
} oItEGJ|
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用户在web层构造查询条件detachedCriteria,和可选的 YRU1^=v
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 y)//u:l
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PaginationSupport的实例ps。 0:C ^-zrx
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ps.getItems()得到已分页好的结果集 !tuN_
ps.getIndexes()得到分页索引的数组 rlRRGJ\l
ps.getTotalCount()得到总结果数 au+6ookT
ps.getStartIndex()当前分页索引 a ]b%v9
ps.getNextIndex()下一页索引 r
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ps.getPreviousIndex()上一页索引 ]K<mkUpY
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si =%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 w]ihGh
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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 ABG>W>H-S
rCH? R
一下代码重构了。 1EmZ/@k/Y
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我把原本我的做法也提供出来供大家讨论吧: o[Gp *o\
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首先,为了实现分页查询,我封装了一个Page类: }L|cg2y
java代码: 7g%.:H=
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/*Created on 2005-4-14*/ nqv#?>Z^OT
package org.flyware.util.page; e0e3b]
CqAv^n7 }
/** O!3`^_.
* @author Joa >|W\8dTQ
* .ng:Z7
*/ mo*ClU7
publicclass Page { +)<H,?/
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/** imply if the page has previous page */ Om,M8!E
privateboolean hasPrePage; X/AA8QV o
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/** imply if the page has next page */ `21$e
privateboolean hasNextPage; r1]DkX <6
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/** the number of every page */ X"fSM
#
privateint everyPage; K/A1g.$
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/** the total page number */ d@QC[$qXj
privateint totalPage; |]=s
,\CG}-v@CN
/** the number of current page */ (
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privateint currentPage; )BX-Y@fpA
uzO3 _.4Y
/** the begin index of the records by the current ~=Q|EhF5
p}K\rpvJpu
query */ $ 0Up.
privateint beginIndex; s9.nU
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/** The default constructor */ 6i=Nk"d
public Page(){ /OsTZ"*.2/
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} ]/TqPOi:
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/** construct the page by everyPage y0b FzR9
* @param everyPage <pp<%~_Z
* */ wPRs.(]_
public Page(int everyPage){ Zt{\<5j
this.everyPage = everyPage; )an,-EIX%
} V+dFL9
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/** The whole constructor */ #fkOm
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public Page(boolean hasPrePage, boolean hasNextPage, ~'3hK4
!1{kG%B=
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int everyPage, int totalPage, f<K7m
int currentPage, int beginIndex){ j87IxB?o
this.hasPrePage = hasPrePage; 1v"r8=Wt
this.hasNextPage = hasNextPage; \*x=q20
this.everyPage = everyPage; \-scGemH
this.totalPage = totalPage; qE)G;Y<,1
this.currentPage = currentPage; <CM}g4Y
this.beginIndex = beginIndex; <cx,Z5W
} .:?cU#.
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/** Xw<5VIAHm;
* @return bR&<vrMmrA
* Returns the beginIndex. FK!UUy;
*/ )WR*8659e
publicint getBeginIndex(){ {WYmO1
return beginIndex; c:f++||
} =F>nqklc
GTBT0$9g.
/** _>)=c<HL
* @param beginIndex z ;KUIWg
* The beginIndex to set. v:w $l{7
*/ =^D{ZZw{
publicvoid setBeginIndex(int beginIndex){ oEuo@\U05v
this.beginIndex = beginIndex; B'`
jdyaE9
} iT}L9\
;x~[om21;
/** 4}>1I}!k
* @return \&)k{P>=
* Returns the currentPage. V9r58hbVT
*/ {I~[a#^
publicint getCurrentPage(){ QnPgp(d<
return currentPage; MI<XLn!*
} z6
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nbM7 >tnsk
/** .}||!
* @param currentPage RI2Or9.
* The currentPage to set. x|oa"l^JZ"
*/ 2`]_c=
publicvoid setCurrentPage(int currentPage){ Qx% ]u8s
this.currentPage = currentPage;
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} %G>|u/:U
8OW504AD
/** DJ#z0)3<p
* @return {Vj25Gt
* Returns the everyPage. DZ9qIc}Y
*/ TV&4m5
publicint getEveryPage(){ {aRZBIv
return everyPage; Vy:MK9U2
} eODprFkt}
^68BxYUoD\
/** c?1:='MC
* @param everyPage x w%'R-
* The everyPage to set. +iL,8eW
*/ 05>xQx?"m4
publicvoid setEveryPage(int everyPage){ R.+yVO2
this.everyPage = everyPage; 7L=V{,,v
} ;"@FLq(n
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/** D@yuldx'/
* @return 8*V8B=q}K
* Returns the hasNextPage. ^-'t`mRl]d
*/ ->S6S_H/+&
publicboolean getHasNextPage(){ ^MZdht
return hasNextPage; 9+sOSz~
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} nPj/C7j
LpJ_HU7@lk
/** 0- 'f1 1S
* @param hasNextPage ,B<Tt|'
* The hasNextPage to set. Hx]{'?
*/ G$buZspL'd
publicvoid setHasNextPage(boolean hasNextPage){ 389puDjy
this.hasNextPage = hasNextPage; s`$px2Gw
} vs)1Rm
tt7l%olw
/** fDa$TbhjI
* @return .C2.j[>
* Returns the hasPrePage. g}hR q%
*/ qt#a_F*rV
publicboolean getHasPrePage(){ 7v~\c%1V
return hasPrePage; F
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} I@f">&^
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/** x_3Zd
* @param hasPrePage {=NHidi~
* The hasPrePage to set. ,6%{9oW9Z:
*/ gl4|D
publicvoid setHasPrePage(boolean hasPrePage){ Q3vWwP;t~
this.hasPrePage = hasPrePage; $ZPiM
} 5 ^\f[}
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/** @zJhJ'~Sl
* @return Returns the totalPage. Z`l97$\
* EPz$`#Sh"
*/ -pRyN]YD
publicint getTotalPage(){ X%1fMC
return totalPage; 8 '2lc
} PG1#Z?_
mYudUn4Wo
/** E!4Qc+.
* @param totalPage Q1Jkt
* The totalPage to set. 3}H"(5dL}z
*/ ve#cz2Z
publicvoid setTotalPage(int totalPage){ oJk$ +v6
this.totalPage = totalPage; 9K8f
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} I!)gXtJA"
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} !@_( W
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I
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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 fWR]L47n
"mAVkq~
个PageUtil,负责对Page对象进行构造: N>OF
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java代码: nFl=D=50-
AcN~Q/xU
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/*Created on 2005-4-14*/ F*QD\sG:
package org.flyware.util.page; =GQ?P*x|$
}0#cdw#gH
import org.apache.commons.logging.Log; cz/mUU
import org.apache.commons.logging.LogFactory; v UAYYe
lX`)Avqa
/** n>\BPiz
* @author Joa {Gs&u>>R"^
* 4yC{BRbi
*/ "w`f>]YLA
publicclass PageUtil { >]=1~sF
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privatestaticfinal Log logger = LogFactory.getLog Zg7~&vs$
xZS
(PageUtil.class); 5cP]
p;) ;Vm+8
/** -o F#a 8
* Use the origin page to create a new page pF.Ws,nQ5
* @param page n(a7%Hx2
* @param totalRecords F5%-6@=
* @return 4i[3|hv'
*/ +I2P{7
publicstatic Page createPage(Page page, int pM\)f
B4&@PX"'>,
totalRecords){ r{kV*^\E
return createPage(page.getEveryPage(), 4(&00#Yxg2
=[`wyQe`_
page.getCurrentPage(), totalRecords); U;KHF{Vm
} [*?P2.b f
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/** ']f]:X;6w
* the basic page utils not including exception T~%5^+[h
7F3Hkvd[k
handler i,ku91T
* @param everyPage ZzI^*Nyg
* @param currentPage M!=v"C#
* @param totalRecords quf,ZK5
* @return page 2Z,;#t
*/ ekP=/;T#S
publicstatic Page createPage(int everyPage, int YjS|Ht->
J mFzSR?}
currentPage, int totalRecords){ [_qBp:_j?s
everyPage = getEveryPage(everyPage); I~"-
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, . xX xjl
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currentPage); d"5:/Mo
int totalPage = getTotalPage(everyPage, )TyL3Z\>(
D2>EG~xWq
totalRecords); )sB`!:~HjP
boolean hasNextPage = hasNextPage(currentPage, "C=HBJdYB5
u[ s+YGS
totalPage); \{G6!dV|S
boolean hasPrePage = hasPrePage(currentPage); ^gky i/z
8c__ U<
returnnew Page(hasPrePage, hasNextPage, 2Pi}<pG~
everyPage, totalPage, 5jy>)WqK
currentPage, QsDab4
?Dm! ;Z+7
beginIndex); H:9(
XW
} DfV_08
wGISb\rr
privatestaticint getEveryPage(int everyPage){ ffm19 B=
return everyPage == 0 ? 10 : everyPage; 3=dGz^Zdv:
} gNs@Q!
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privatestaticint getCurrentPage(int currentPage){ I U4[}x
return currentPage == 0 ? 1 : currentPage; ":"M/v%F
} sNX$ =<E
R,Tw0@{O*
privatestaticint getBeginIndex(int everyPage, int ,3GM'e{hV
w^`n
currentPage){ |}q0G~l
return(currentPage - 1) * everyPage; <`|}bt
} K~,,xsy,G&
o?p) V^7
privatestaticint getTotalPage(int everyPage, int }tv-
gMI%z2]'-
totalRecords){ B7}-g"p$/
int totalPage = 0; ,{8~TVO
9KXp0Q?-$
if(totalRecords % everyPage == 0) r7ywK9UL
totalPage = totalRecords / everyPage; tk}qvW.Ii
else ,*S?L
qv^
totalPage = totalRecords / everyPage + 1 ; 3tIIBOwg[
"t"dz'
return totalPage; Uk;SY[mU
} 4ItXZ o
T
X6Ydd
privatestaticboolean hasPrePage(int currentPage){ `2S{.s
return currentPage == 1 ? false : true; eIof{#
} mL6/NSSz
KDQux
privatestaticboolean hasNextPage(int currentPage, <hy>NM@$
HSK^vd?_l
int totalPage){ ,~G _3Oz
return currentPage == totalPage || totalPage == y62;&{?m
uVscF
4
0 ? false : true; Nob(bD5SpE
} w0*6GCP
8 (.<
rKJ%/7m
} Uut,cQ". d
v S%+
e@8I%%V,
},i?3dSvl
te:"1:e
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。 D;d;:WT5
wau81rSd
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 79x^zqLb
*^.b}K%
做法如下: -BoN}xE4
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}k!i+Yl
B[$KnQM9Y
的信息,和一个结果集List: o~iL aN\+
java代码: })!n1kt
ARU,Wtj#
e2B~j3-?z
/*Created on 2005-6-13*/ j./bVmd.
package com.adt.bo; eyAg\uuih
M
$e~Rlw
import java.util.List; MQG$J!N
*Z/B\nb
import org.flyware.util.page.Page; "
*Ni/p$I
9m6w.:S
/** /pb7
* @author Joa #Wc)wL-Tg
*/ bJBx~
publicclass Result { 3`e1:`Hu
IRS^F;)
private Page page; }qlz^s
=e._b 7P
private List content; R [uo:.
~Kb(`Px@
/** =G=.THRUk
* The default constructor i:[B#|%
*/ d1E~H]X4
public Result(){ 9d2$F9]:o
super(); ORHC bw9
} d!wd,Xj}
wk5a &
/** `>#X,Lw$g
* The constructor using fields <M\Z}2 d
* Q kQd;y
* @param page 6Jj)[ R\5=
* @param content ?_tOqh@in
*/ #bdJ]v.n
public Result(Page page, List content){ 5Cz:$-+
this.page = page;
=6A<>
this.content = content; T+.wJW:jh
} '*~{1gG `
:nXBw%0x
/** `b% /.%]$
* @return Returns the content. G&n_vwZ%
*/ 2qn~A0r
publicList getContent(){ _`D_0v(X
return content; KM\`,1?x92
} f%|g7[
GuS3O)6Sg
/** .OWIlT4K
* @return Returns the page. *aT!|;
*/ `\.n_nM
public Page getPage(){ {_
1q`5o
return page; W&p-Z"=)
} j?8E >tM
_@RW7iP>
/** cdGl[dQ/
* @param content 0 /H1INve
* The content to set. 1zp,Suv
*/ }h]:I'R!
public void setContent(List content){ 6 8_UQ.
this.content = content; )0'O!O
} <A6<q&g|E
Tw`l4S&
/** Hv
IN'
* @param page p,1RRbyc
* The page to set. GdP9Uj)n-
*/ #pVk%5N
publicvoid setPage(Page page){ )1i)I?m
this.page = page; <w:fR|O
} C<7J5
} ! TRiFD
%-SP
~&qe"0
I7Eg$J&
fcBSs\\C~
2. 编写业务逻辑接口,并实现它(UserManager, y1AS^'
^1nf|Xj[
UserManagerImpl) WW_X:N~~e\
java代码: aY?}4Bx
4t+88e
1ii.nt1u
/*Created on 2005-7-15*/ RoiMvrJQP
package com.adt.service; v
EX <9
UU !I@
import net.sf.hibernate.HibernateException; [+%*s3`c#
v>e4a/
import org.flyware.util.page.Page; REsThB
}@#eD
import com.adt.bo.Result; . =+7H`A
LTCjw_<7
/** \:#b9t{B-
* @author Joa mPh;
*/ q)vD "{0.
publicinterface UserManager { D\TL6"wo
[v&_MQ
public Result listUser(Page page)throws jIW:O
IrVeP&KM+
HibernateException; !hc7i=V?
V]8fn MH
} ruW6cvsvet
xpnnWHdaq
KOxD%bX_
[|>.iH X
2sTyuH.
java代码: p\HXE4d'
IW46-;l7
k^L (q\D
/*Created on 2005-7-15*/ j C@^/rMh
package com.adt.service.impl; l)|CPSN?w
vB,N6~r>
import java.util.List; 6SmSu\lgV
:[rx|9M6
import net.sf.hibernate.HibernateException; 'X?`+2wK
o+vf
import org.flyware.util.page.Page; YnMph0\Y^
import org.flyware.util.page.PageUtil; bw[!f4~
>i.+v[)#
import com.adt.bo.Result; 8R
z=)J
import com.adt.dao.UserDAO; #eaey+~
import com.adt.exception.ObjectNotFoundException; f(C0&"4e
import com.adt.service.UserManager; h>n;A>k@N
}Yt0VtLt
/** v3/cNd3
* @author Joa QO
k%Q$^G
*/ B;@yOm=
publicclass UserManagerImpl implements UserManager { RDZq(rKc
m ;KP
private UserDAO userDAO; uaGg8
Ff,M~zn
/** BBx"{~
* @param userDAO The userDAO to set. s 2$R2,
*/ OO$<Wgh
publicvoid setUserDAO(UserDAO userDAO){ s810714
this.userDAO = userDAO; *=
D$
} IKU-
dV5$L
e#y
/* (non-Javadoc) QL)UPf>Kp
* @see com.adt.service.UserManager#listUser -8o8lz
JE j+>
(org.flyware.util.page.Page) J+;.t&5R
*/ F3qi$ 3HM
public Result listUser(Page page)throws !9!Ns(vUM
ecFI"g
HibernateException, ObjectNotFoundException { o0/03O
int totalRecords = userDAO.getUserCount(); Qh *|mW
if(totalRecords == 0) OUs2)H61
throw new ObjectNotFoundException !At _^hSqz
o#T,vu0s
("userNotExist"); |9%>R*
page = PageUtil.createPage(page, totalRecords); "[8](3\v
List users = userDAO.getUserByPage(page); $nVTN.k
returnnew Result(page, users); V^0*S=N
} $'&5gFr9
vxwctJ&
} }:BF3cH> 0
USbiI%
06ueE\@Sg
Rub"" Ga
v-l):TL+=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 DB*IVg
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w{
询,接下来编写UserDAO的代码: [$V_qFv{
3. UserDAO 和 UserDAOImpl: I8[G!u71)_
java代码: 6zDJdE'Es
hVlL"w*1
_W!g'HP-D
/*Created on 2005-7-15*/ qBpY3]/
package com.adt.dao; eg}|%GG
w3& F e=c
import java.util.List; c_".+Fa
$$8"i+,K
import org.flyware.util.page.Page; 9LFg":
T&!>lqU!J
import net.sf.hibernate.HibernateException; +zlaYHj
W<x2~HW(
/** 6=& wY
* @author Joa R=IeAuZR4k
*/ w@"|S_E
publicinterface UserDAO extends BaseDAO { 'rg$%M*(
9<Bf5d
publicList getUserByName(String name)throws S`R
( _eD@
x3vz4m[
HibernateException; B!Qdf8We
Bb1dH/8
publicint getUserCount()throws HibernateException; C[pAa 8
}&!rIU
publicList getUserByPage(Page page)throws >N*QK6"=|
;~@2YPj
HibernateException; dJ|]W|q<
PGybX:L
} YsTfv1~z#
zX5p'8-
d8x$NW-s
O" z=+79q
/ '7WL[<
java代码: Ek4aC3
?d_Cy\G
MVTU$
65
/*Created on 2005-7-15*/ p%G\5.GcJL
package com.adt.dao.impl; Xu'u"amt
PM_q"}-
import java.util.List; B0YY7od
Fc nR}TE
import org.flyware.util.page.Page; JL*-L*|Zcl
}q~A( u
import net.sf.hibernate.HibernateException; Z|j8:Ohz
import net.sf.hibernate.Query; \V&ly/\
)
L$jRg
import com.adt.dao.UserDAO; +ivz
ir\
/** %;zA_Wg
* @author Joa
PL
VF
*/ 2S/^"IM["
public class UserDAOImpl extends BaseDAOHibernateImpl 8Mp
\"f}Fx
implements UserDAO { Bd7A-T)q!
q_W NN/w
/* (non-Javadoc) 8..itty
* @see com.adt.dao.UserDAO#getUserByName =g&0CFF <
i=SX_#b^
(java.lang.String) UL{Xe&sT
*/ E(S}c*05O
publicList getUserByName(String name)throws aEgzQono
fCTjTlh
HibernateException { D}_\oE/n
String querySentence = "FROM user in class #7g~Um%p
S4tdWA
com.adt.po.User WHERE user.name=:name"; ah}aL7dgO
Query query = getSession().createQuery ^beW*O!
xxedezNko
(querySentence); kDm=Cjxv
query.setParameter("name", name); CqF<
BE
return query.list(); ]{;K|rCR-
} ]r#tJT`M
bb#w]!q
/* (non-Javadoc) nhy3E
* @see com.adt.dao.UserDAO#getUserCount() 6%5A&&O(b
*/ @5kN
L~2
publicint getUserCount()throws HibernateException { aUJ&
int count = 0; q!FJP9x
String querySentence = "SELECT count(*) FROM qg'm<[
'QkL%z0
user in class com.adt.po.User"; ,;{mH]"s
Query query = getSession().createQuery zZA I"\;W
I]} MK?
(querySentence); 45_zO#
count = ((Integer)query.iterate().next <x1(}x:u`
!IT']kA
()).intValue(); sSvQatwS
return count; TeG'cKz
} v_Jp9
MenI>gd?
/* (non-Javadoc) 6)H70VPJ
* @see com.adt.dao.UserDAO#getUserByPage t<$yxD/R
2Ejs{KUj
(org.flyware.util.page.Page) fXL$CgXG\x
*/ 9@^/ON\O
publicList getUserByPage(Page page)throws wCkkfTO
&yYK%~}t[
HibernateException { id*UTY
Tg
String querySentence = "FROM user in class S__ o#nf`%
4}l,|7_&I
com.adt.po.User"; 2O4UytN
Query query = getSession().createQuery esxU44
&hZcjdB
(querySentence); =n$,Vv4A
query.setFirstResult(page.getBeginIndex()) Gd"lB*^Ht
.setMaxResults(page.getEveryPage()); AR)&W/S)7,
return query.list(); f)*}L?
} S"fnT*:.%
gmrjCLj
} in%+)`'nH7
@P)GDB7A
#opFUX-
lZb1kq%9g
=WN6Fj`
至此,一个完整的分页程序完成。前台的只需要调用 JP[BSmhAV
kkqrlJO|
userManager.listUser(page)即可得到一个Page对象和结果集对象 Prr<:q
a-O9[?G/x
的综合体,而传入的参数page对象则可以由前台传入,如果用 \ar.(J
koaH31Q
webwork,甚至可以直接在配置文件中指定。 0xH$!?{b
+DVU"d
下面给出一个webwork调用示例:
#p\sw
java代码: Z\NC+{7k]
VP|9Cm=Fg
`kFxq<?aK
/*Created on 2005-6-17*/ jb77uH_
package com.adt.action.user; o.sa?*
3}XUYF;
import java.util.List; ;)UZT^f`)K
EV]exYWB
import org.apache.commons.logging.Log; =#uXO<
import org.apache.commons.logging.LogFactory; "j~=YW+l
import org.flyware.util.page.Page; 9t;aJFI
rMLCtGi
import com.adt.bo.Result; CK.Z-_M
import com.adt.service.UserService; KJSN)yn\
import com.opensymphony.xwork.Action; e}7qZ^
AD~\/V&+
/** L(}T-.,Slr
* @author Joa $(C71M|CT
*/ P3(u+UI3
publicclass ListUser implementsAction{ }1'C!]j
pNE!waR>
privatestaticfinal Log logger = LogFactory.getLog v!40>[?|p
$] w&`F-
(ListUser.class); 6nxf<1
,TP^i 0
private UserService userService; @{~x:P5g
U4M!RdG
private Page page; zYF'XB]4
%!x\|@C
privateList users; 6\'v_A
O
>b<br
/* Z+Z`J;
,
* (non-Javadoc) <L:v2 8c
* 6`F_js.a
* @see com.opensymphony.xwork.Action#execute() {8b6A~/
*/ !t[X/iu
publicString execute()throwsException{ 1\_4# @')
Result result = userService.listUser(page); :aco$ZNH5
page = result.getPage(); Qp%kX@Z'
users = result.getContent(); llQDZ}T
return SUCCESS; kg+"Ta[9
} >m%\SuXq
YdIV_&-W
/** ?I7%@x!+S
* @return Returns the page. c_&iGQ
*/ Ks9"U^bPs
public Page getPage(){ fv#e 8y
return page; dht1I`i"B
} T4._S:~
[+>$'Du
/** ~h0SD(
* @return Returns the users. u'LA%l-
*/ Pp#!yMxBr
publicList getUsers(){ Jg|/*Or
return users; NCX!ss
} 6-<,1Q'D
Gz$DsaG
/** eH79,!=2
* @param page %xkqiI3Ff
* The page to set. P4ot,Q4
*/ Y{um1)k
publicvoid setPage(Page page){ 0Tg/R4dI
this.page = page; a&4>xZU #
} ejD;lvf
En-eG37l
/** = DvnfT<
* @param users zgqe@;{
* The users to set. 8[
:FU
*/ t~Ds)
publicvoid setUsers(List users){ CKrh14ul
this.users = users; @(&ki~+
} JrS/"QSA
M
HlP)'
/** q<.^DO~$L
* @param userService }Geip@Ot
* The userService to set. P g7W:L7
*/ y7$e7~}/
publicvoid setUserService(UserService userService){ 3mpEF<z
this.userService = userService; Fg`r:,(a
} GfPe0&h
} Ku 56TH!Py
&2#<6=}
Kx$?IxZ
(m~MyT#S
ub./U@1
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, cM.q^{d`
K|E}Ni
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 F(}d|z@@
rsy'ZVLUj
么只需要: n"d~UV^Uw
java代码: NTls64AS.
?cowey\m
.
Z'PL?;&+R
<?xml version="1.0"?> lg;`I tX]
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork (Q\QZu@
-9vAY+s.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +2MsyA?6_
9e1gjC\ c
1.0.dtd"> ] QtG gWtC
bG;vl;C
<xwork> l*xA5ObV
u*}6)=+:
<package name="user" extends="webwork- B5P++aQ
sm4@ywd>
interceptors"> q$~S?X5\
Fu!:8Wp!(
<!-- The default interceptor stack name $A8eMJEpL
c;BQ$je}
--> r]"
>
<default-interceptor-ref (a@cK,
b{(!Ls_ &
name="myDefaultWebStack"/> WcbJ4Ore
qS+'#Sn
<action name="listUser" SQW A{f
N@Bqe{r6j
class="com.adt.action.user.ListUser"> ib*$3Fn~
<param 5"]PwC
~+V]MT
name="page.everyPage">10</param> y/4 4((O
<result 64o`7
"?}QwtUW
name="success">/user/user_list.jsp</result> GVCyVt[!-
</action> <@(HQuL#
JwxI8Pi*y
</package>
> ")%4@
a}El!7RO0
</xwork> w~&bpCB!
Kx ?}%@b
x!]ZVl]
hRtnO|Z6
$BkdC'D
4VD'<`R[
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ezC55nm
^5QSV\X
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 C
`k^So)
=+A8s$Pb
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Q^ bG1p//.
h&;\
fb&K.6"
+SZ#s:#SE
~$YFfv>
我写的一个用于分页的类,用了泛型了,hoho gXc&uR0S
I `p44}D3
java代码: b;Q
cBGwKT
HaJD2wvr
80c\O-{
package com.intokr.util; i!ejK6Q
N;;!ObVHnP
import java.util.List; Z!^iPB0~D
bmzs!fg_~R
/** ~KHp~Xs`
* 用于分页的类<br> onHUi]yYu{
* 可以用于传递查询的结果也可以用于传送查询的参数<br> u
L/*,[}'
* f*bs{H'5
* @version 0.01 2Q-kD?PO,
* @author cheng `+k&]z$m
*/ ZWh:&e(
public class Paginator<E> { .'L@$]!G
privateint count = 0; // 总记录数 a~:'OW:Q
privateint p = 1; // 页编号 H:a(&Zb
privateint num = 20; // 每页的记录数 [ wr0TbtV
privateList<E> results = null; // 结果 Xp4pN{h e
&&Vz=6N
/** &*T57tE
* 结果总数 s
<Ag8U8
*/ htkn#s~=
publicint getCount(){ Jg/WE1p>
return count; (B7M*e
} /J wQ5
}V6}>!Sb
publicvoid setCount(int count){ 9iUkvnphh
this.count = count; |JnJ=@-y
} 6 @'v6 1'
QR\qGhQ~
/** 'FO^VJ;ha
* 本结果所在的页码,从1开始 O`rAqO0F
* rnEWTk7&
* @return Returns the pageNo. :M'3U g$t
*/ U3ED3)
D
publicint getP(){ +c+#InsY
return p; ~~&8I!r e
} "Do9gW
CdC&y}u
/** ){5$8
* if(p<=0) p=1 Rb',"` 7
* k%VV(P]sT
* @param p 0 \&4?
*/ CQ"5bnR
publicvoid setP(int p){ drNfFx2
if(p <= 0) =cX&H
p = 1; oju4.1
this.p = p; !E4YUEY6
} 7:9WiN5b
{CYFM[V
/** yLipuMNV
* 每页记录数量 pN1W|Wv2
*/ xzAyE5GL>
publicint getNum(){ `:R8~>p
return num; gX.4I;
} AdKv!Ta5b
1`X{$mxw
/** ko=vK%E[
* if(num<1) num=1 gM^ Hs7o,
*/ bTb|@
publicvoid setNum(int num){ <vhlT#p
if(num < 1) D}&U3?g=
num = 1; 9p9:nx\
this.num = num; eM*@}3
} cK1r9ED|
Bd31>
%6
/** H+;>>|+:~
* 获得总页数 #q6jE
*/
BJB'o
publicint getPageNum(){ ? R#-gvX%
return(count - 1) / num + 1; m!tB;:6
} Go=MG:`
3l-8TR
/** <;=?~QK%-
* 获得本页的开始编号,为 (p-1)*num+1 o/)]z
*/ QZYD;&iY&
publicint getStart(){ ")i4w{_y
return(p - 1) * num + 1; pbl;n|
} E&7U |$
l]uF!']f
/** 5)AMl)
* @return Returns the results. &Plc
*/ Dc}-wnga
publicList<E> getResults(){ q~T*R<S
return results; !c[?$#W4
} u?&P6|J&
W{*U#:Jx1
public void setResults(List<E> results){ Cz#0Gh>1
this.results = results; }[ld=9p(
} ;vy" i
9B{,q6
public String toString(){ +>M^p2l*&
StringBuilder buff = new StringBuilder `gDpb.=Y
.Wc<(pfa
(); p$`71w)'[
buff.append("{"); O@ F0UM`!
buff.append("count:").append(count); RpOGY{[)[
buff.append(",p:").append(p); y
U
=) g
buff.append(",nump:").append(num); K7 -AVMY
buff.append(",results:").append ; $i{>mDT
|D~mLs;&
(results); %iPWg
buff.append("}"); | (JxtQqQg
return buff.toString(); MX2]Q
} "v@Y[QI
l=GcgxD+"d
} 3CL/9C>
3LN+gXmU
'y[74?1