Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 5SKj% %B2,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Y S )Q#fP
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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
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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 &y"e|aE
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分页支持类: ew8f7S[
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java代码: CU'$JF
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package com.javaeye.common.util; X,dOF=OJL
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import java.util.List; _GSl}\
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publicclass PaginationSupport { AdV&w: ^yf
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publicfinalstaticint PAGESIZE = 30; vqDd][ n
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privateint pageSize = PAGESIZE; w+c%Y\:
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privateList items; /, T@/
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privateint totalCount; ^]_[dqd
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privateint[] indexes = newint[0]; ;
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privateint startIndex = 0; >p"ytRu^
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public PaginationSupport(List items, int \/E+nn\)
}',/~T6
totalCount){ X.^S@3[
setPageSize(PAGESIZE); M@\A_x(Mas
setTotalCount(totalCount); 36ygI0V_
setItems(items); t.0F
setStartIndex(0); 4#j W}4C{
} DbDi n
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public PaginationSupport(List items, int y>4r<YZQ
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totalCount, int startIndex){ jx*jYil
setPageSize(PAGESIZE); j0^%1
setTotalCount(totalCount); O"%b@$p\L
setItems(items); \v|nRn,`-
setStartIndex(startIndex); r57CyO
} :xqhPr]e
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public PaginationSupport(List items, int Yi?X|"\`
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totalCount, int pageSize, int startIndex){ RRXnj#<g
setPageSize(pageSize); Ph{7S43
setTotalCount(totalCount); W@"s~I6
setItems(items); E]T>m!6
setStartIndex(startIndex); =~qQ?;on
} u`K)dH,
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publicList getItems(){ l~_]k
return items; 2L\}
} &`]Lg?J
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publicvoid setItems(List items){ ^tp6G
this.items = items; .
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} . }#R
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publicint getPageSize(){ Ii*tux!S
return pageSize; |r|<cc#
} r
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publicvoid setPageSize(int pageSize){ idG}p+(;
this.pageSize = pageSize; i!AFXVX
} hU:
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publicint getTotalCount(){ `1O<UJX
return totalCount; [Un~]E.'J
} F},#%_4
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publicvoid setTotalCount(int totalCount){ 1$+-?:i C
if(totalCount > 0){ /"Z6\T9
this.totalCount = totalCount; _lK+/"-l
int count = totalCount / NA=I7I@
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pageSize; Ah_,5Z@&R
if(totalCount % pageSize > 0) D]P_tJI
count++; L4Nn:9b
indexes = newint[count]; j'\!p):H
for(int i = 0; i < count; i++){ obRYU|T
indexes = pageSize * 6ct'O**k*&
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i; T(@J]Y-
} )qbjX{GZ7
}else{ @2X{e7+D
this.totalCount = 0; 3?n2/p
7=
} F"G]afI9+
} Exu5|0AAE
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publicint[] getIndexes(){ Oh&k{DWE$
return indexes; G(Ky7SZ
} 6g6BE^o\
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publicvoid setIndexes(int[] indexes){ WP}NHz4H
this.indexes = indexes; _MmSi4]yd
} #?3oGrS Y
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publicint getStartIndex(){ ;A\SbLM
return startIndex; ]-2Q0wTj
} *)8!~Hs
79yF {
publicvoid setStartIndex(int startIndex){ SJ%h.u@&@F
if(totalCount <= 0) 3$~oQC
this.startIndex = 0; TF[8r[93
elseif(startIndex >= totalCount) i(9 5=t(
this.startIndex = indexes )%(V.?eW
S.! n35
[indexes.length - 1]; CI8bHY$
elseif(startIndex < 0) E3~ Wyfd7
this.startIndex = 0; 8TE2q Pm
else{ p~evPTHnrX
this.startIndex = indexes S=^kR [O"
zF7*T?3b"
[startIndex / pageSize]; =-dg]Ol8
} gK#G8V-,
} DKG99biJN
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publicint getNextIndex(){ [AA*B
int nextIndex = getStartIndex() + g.]S5(
9e _8Z@|
pageSize; K1oSoD8c
if(nextIndex >= totalCount) >s;>"]
return getStartIndex(); ;) (F4
else ,?KN;~t#vz
return nextIndex; M/LC:,
} ;3P~eeQR
ui!MQk+D9
publicint getPreviousIndex(){ )1ct%rue
int previousIndex = getStartIndex() - =}xH6^It
lmbC2\GT
pageSize; 8w\ZY>d
if(previousIndex < 0) z <jH{AU
return0; i9=*ls^Cx
else Kd|@
return previousIndex; =K8z8K?
} nf,u'}psdJ
}M|,Z'@*
} S uo
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抽象业务类 (d?sFwOt\
java代码: %kXg|9Bx!
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/** S
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* Created on 2005-7-12 EpdSsfDP
*/ 0~GtK8^B
package com.javaeye.common.business; 2(s-8E:
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import java.io.Serializable; qf?X:9Wt
import java.util.List; grbUR)f<?-
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import org.hibernate.Criteria; 7>$&CWI
import org.hibernate.HibernateException; P; DGs]PF
import org.hibernate.Session; n~C!PXE
import org.hibernate.criterion.DetachedCriteria; 01&J7A2
import org.hibernate.criterion.Projections; D)){"Q!b
import `44 }kkBT
*)0-N!N#)
org.springframework.orm.hibernate3.HibernateCallback; ["}Yp
import Qk#`e
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org.springframework.orm.hibernate3.support.HibernateDaoS aPH6R<G
*c{X\!YBh
upport; Lju)q6
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import com.javaeye.common.util.PaginationSupport; t/Y)% N
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public abstract class AbstractManager extends ;lU]ilYv
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HibernateDaoSupport { JoIh2P D
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privateboolean cacheQueries = false; H;k-@J
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privateString queryCacheRegion; d%w#a3(
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publicvoid setCacheQueries(boolean SM1[)jZ-
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cacheQueries){ _+NM<o#A
this.cacheQueries = cacheQueries; = k7}[!T
} MQ7Hn;`B
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publicvoid setQueryCacheRegion(String R(dOQ. ;
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queryCacheRegion){ =*Ru2
this.queryCacheRegion = ._A@,]LS}
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queryCacheRegion; Kh,zp{
} '%\FT-{
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publicvoid save(finalObject entity){ nQ}$jOU&
getHibernateTemplate().save(entity); 9:1[4o)~
} 7'1 +i
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publicvoid persist(finalObject entity){ v>oWk:iJP
getHibernateTemplate().save(entity); u>-pgu
} @b5zHXF83E
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publicvoid update(finalObject entity){ d&apu{
getHibernateTemplate().update(entity); Lj#K^c Ee
} 9zs!rlzQ
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publicvoid delete(finalObject entity){ wOU\&u|
getHibernateTemplate().delete(entity); <-rw>,
} }V I}O{
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publicObject load(finalClass entity, [t }\8^y
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finalSerializable id){ .|Y&,?k|Y
return getHibernateTemplate().load I?Fv!5p
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(entity, id); IqrT@jgN-
} 'vc>uY
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publicObject get(finalClass entity, iB0#Z_
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finalSerializable id){ `%oJa`
return getHibernateTemplate().get e|2@z-Sp-
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(entity, id); ZA {T0:
} C0v1x=(xiM
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publicList findAll(finalClass entity){ 9Impp5`/B
return getHibernateTemplate().find("from qOM" ?av
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" + entity.getName()); o{r<=X ysM
} \!Cc[n(f#
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publicList findByNamedQuery(finalString .`@)c/<0
q"C(`S.@
namedQuery){ }XcYIo#+t
return getHibernateTemplate {$H-7-O$
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().findByNamedQuery(namedQuery); %3;vDB*L$
} g+1&l iV
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publicList findByNamedQuery(finalString query, tkjQSz
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finalObject parameter){ 7xU6Ll+p
return getHibernateTemplate RJhafUJ zH
m(DJ6CSa
().findByNamedQuery(query, parameter); TG^?J`
} sDXD>upO
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publicList findByNamedQuery(finalString query, mi]bS
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finalObject[] parameters){ lC8Z@wkjO
return getHibernateTemplate 4-vo R5Fd
eg Xbe)ld
().findByNamedQuery(query, parameters); %<]4]h
} c0aXOG^
j0`)m R}
publicList find(finalString query){ 5x? YFq6k
return getHibernateTemplate().find 4}xw&x
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(query); 9Rd&Jq^
} pB5#Ho>S
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publicList find(finalString query, finalObject ?%A9}"q]
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parameter){ YMr2|VEU[
return getHibernateTemplate().find P+:DLex
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(query, parameter); J5Ovj,[EZ
} {3`cSm6c
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public PaginationSupport findPageByCriteria e%_J
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(final DetachedCriteria detachedCriteria){ Q&]f9j_
return findPageByCriteria z; Jz^m-
/N9ct4 {^
(detachedCriteria, PaginationSupport.PAGESIZE, 0); O;lGh1.
} c4V%>A
fW=vN0Z
public PaginationSupport findPageByCriteria cw3j&k
7SJR_G6,{
(final DetachedCriteria detachedCriteria, finalint 4&kC8
[ r
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startIndex){ NH'Dz6K5
return findPageByCriteria 572{DC&T
_)kTlX:,
(detachedCriteria, PaginationSupport.PAGESIZE, b[KZJLZ)
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startIndex); eXQLE]L]
} 0fzHEL
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public PaginationSupport findPageByCriteria ")YD~ZA%)
/b7]NC%
(final DetachedCriteria detachedCriteria, finalint Ef$a&*)PH
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pageSize, b4&l=^:e=
finalint startIndex){ Vbv)C3ezD
return(PaginationSupport) H~
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getHibernateTemplate().execute(new HibernateCallback(){ bH.SUd)
publicObject doInHibernate UvR.?js(O
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(Session session)throws HibernateException { R} X"di
Criteria criteria = UC_o;
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detachedCriteria.getExecutableCriteria(session); {l"(EeW6)
int totalCount = 0`V;;w8
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((Integer) criteria.setProjection(Projections.rowCount 9ZNzC
i!
Z!-V&H.
()).uniqueResult()).intValue(); n^|SN9_r
criteria.setProjection {)(Mkm+d
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(null); mUy>w
List items = iG#92e4
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criteria.setFirstResult(startIndex).setMaxResults RzU9]e
tOX-vQ
(pageSize).list(); A4g,)
PaginationSupport ps = w75Ro6y
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new PaginationSupport(items, totalCount, pageSize, 9k\M<jA
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startIndex); Hy5 6@jW+E
return ps; v"o_V|
} +/
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}, true); G5%k.IRz
} # [
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public List findAllByCriteria(final fR?'HsQg
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DetachedCriteria detachedCriteria){ 3?D{iMRM
return(List) getHibernateTemplate ?D|kCw69SE
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().execute(new HibernateCallback(){ I5)$M{#a
publicObject doInHibernate !L(
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(Session session)throws HibernateException { g}S%D(~
Criteria criteria = wwv+s ~(0
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detachedCriteria.getExecutableCriteria(session); EEMRy
return criteria.list(); rp^:{6O
} @REMl~"D5
}, true); 4 L
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} 0dQ\Y]b
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public int getCountByCriteria(final @^J>. g
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DetachedCriteria detachedCriteria){ C4GkFD
Integer count = (Integer) <EdNF&S-
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getHibernateTemplate().execute(new HibernateCallback(){ -knP5"TB
publicObject doInHibernate }346uF7C
>vR2K^
(Session session)throws HibernateException { !]5V{3
Criteria criteria = Sn^M[}we
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detachedCriteria.getExecutableCriteria(session); 1|AY&u%fiP
return p$ETAvD
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criteria.setProjection(Projections.rowCount +md"X@k5*
o\PHs4Ws'7
()).uniqueResult(); 7z&$\qu2
} KV-h~C
}, true); v T
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return count.intValue(); qq_ZkU@xg
} I[?bM-
} /{P-WRz>
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用户在web层构造查询条件detachedCriteria,和可选的 ;g;1<?
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 aR'~=t&;z1
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PaginationSupport的实例ps。 ImD&~^-_<
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ps.getItems()得到已分页好的结果集 f"NWv!
ps.getIndexes()得到分页索引的数组 }W(t>>
ps.getTotalCount()得到总结果数 &}|`h8JA]K
ps.getStartIndex()当前分页索引 }f% Qk0^
ps.getNextIndex()下一页索引 l8 $.k5X
ps.getPreviousIndex()上一页索引 $9xp@8b\_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 dWe%6s;
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 "3|OB, <;:
@v!#_%J
一下代码重构了。 S v#,L8f
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我把原本我的做法也提供出来供大家讨论吧: -V[!qI
kA)`i`gt
首先,为了实现分页查询,我封装了一个Page类: }W[=O:p
java代码: O*B9Bah
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/*Created on 2005-4-14*/ tB4yj_ZF
package org.flyware.util.page; ~"4Cz27
0]$-}AYM
/** v6E5#pse8
* @author Joa ZP&iy$<L
* 8<KC-|y.
*/ )7Qp9Fxo
publicclass Page { ^ P
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yJlRW!@&:
/** imply if the page has previous page */ ,JTyOBB<I
privateboolean hasPrePage; SJi;_bVf
P3Ah1X7W"C
/** imply if the page has next page */ 1=!2|D:C)i
privateboolean hasNextPage; 0tPwhJ
5lM 3In@
/** the number of every page */ i.eMrzJ|
privateint everyPage; 0;*[}M]Z
0AoWw-H6V
/** the total page number */ JS<w43/j
privateint totalPage; k)y<iHR_o
322-'S3<
/** the number of current page */ De>,i%`Q,D
privateint currentPage; w
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/ T_v8{D
/** the begin index of the records by the current ycvgF6Me<
6x/o j`_[
query */ "d
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privateint beginIndex; !|9k&o
EQM[!g^a
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/** The default constructor */ U7,.L
public Page(){ _G/uDP%
+Q[SddI
} &g0r#K
Q7UQwAN'
/** construct the page by everyPage 9+.3GRt7
* @param everyPage T8W^qrx.v
* */ <A`SC;k\u
public Page(int everyPage){ |Vu`-L'Jz
this.everyPage = everyPage; ?nE9@G5Gc
} F<dhG>E9
[[ Nn~7
/** The whole constructor */ {?A/1q4rr
public Page(boolean hasPrePage, boolean hasNextPage, J @IKXhb7_
t~qAA\p}o
P86wRq
int everyPage, int totalPage, M~Er6Zg
int currentPage, int beginIndex){ c{x:'@%/s'
this.hasPrePage = hasPrePage; PfhKomt"
this.hasNextPage = hasNextPage; ,Hp7`I>/
this.everyPage = everyPage; \`-xxhb?e
this.totalPage = totalPage; U><$p{)
this.currentPage = currentPage; 58`Dcx,yJ
this.beginIndex = beginIndex; N&(MM.\`^
} F+W{R+6
TIF =fQ
/** _BCq9/
* @return p`!<yq2_
* Returns the beginIndex. gnf4H
V~
*/ o+- 0`!yj
publicint getBeginIndex(){ u_o]\D~
return beginIndex; f>Tn#OW
} SxkY ;^-U
/NuO>kQa
/** kp6 &e
* @param beginIndex qmNG|U&
* The beginIndex to set. 20:![/7:!
*/ bY~V?yNgKM
publicvoid setBeginIndex(int beginIndex){ vJX0c\e
this.beginIndex = beginIndex; H5CL0#I
} $wl_
V%`\x\Xat
/** dMI G2log
* @return Odw9]`,T
* Returns the currentPage. y6H`FFqK
*/ /7ykmW
publicint getCurrentPage(){ f'Oj01[
return currentPage; QQ %W3D@
} Nkn2\w
^pqJz^PO.
/** pTH5-l_f]
* @param currentPage u!t<2`:h
* The currentPage to set. E[FE-{B#
*/ ^#4<~zU
publicvoid setCurrentPage(int currentPage){ 02YmV%
this.currentPage = currentPage; s+h}O}RV
} 0E@*&Ru
,y}~rYsP%
/** j&q%@%Gm
* @return ROO@EQ#`Z
* Returns the everyPage. .F/s(
*/ *De'4r 2
publicint getEveryPage(){ _auFt"n
return everyPage; yIWgC[
} uSH_=^yTQ
E=]|v+#~
/** <driD'=F
* @param everyPage Xwd9-:
* The everyPage to set. _s}`ohKvD
*/ s|k&@jH)
publicvoid setEveryPage(int everyPage){ c IPOI'3d
this.everyPage = everyPage; eAjsMED
} s?
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bKEiS8x
/** yA';~V\V{>
* @return F(Je$c/J|~
* Returns the hasNextPage. 7j88^59
*/ 7"OJ,Mx%
publicboolean getHasNextPage(){ -wh
return hasNextPage; 3u<
ntx ><
} vx}BTH
W>'(MB$3
/** F45-M[z
* @param hasNextPage 1*.*\4xo
* The hasNextPage to set. u-QHV1H`(
*/ NCgKWyRR
publicvoid setHasNextPage(boolean hasNextPage){ ZKM@U?PK
this.hasNextPage = hasNextPage; (O&HCT|
} ]zn3nhBI
.Ad9(s
/** 69`*u<{PC
* @return 8\jsGN.$JZ
* Returns the hasPrePage. o'8nQ
Tao
*/ g{f7} gTG
publicboolean getHasPrePage(){ I+31:#d
return hasPrePage; 9Q'[>P=1
} -aV(6i*n
`Jh<8~1
/** *,~L_)vWO
* @param hasPrePage Eu%E2A|`I
* The hasPrePage to set. e0j4t-lL
*/ E()%IC/R
publicvoid setHasPrePage(boolean hasPrePage){ ^x_$%8
this.hasPrePage = hasPrePage; {qOqtkj
} B:Awy/XMi
e3?z^AUXm
/**
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* @return Returns the totalPage. O 0$V+fE
* Ey=}bBx
*/ /_YTOSZjm
publicint getTotalPage(){ 12;YxW>[
return totalPage; wuW{2+)B
} 5"X@<;H%
mkrVeBp
/** kt=&mq/B
* @param totalPage \L`x![$~q
* The totalPage to set. IW-|"5?9'
*/ 9,JWi{lIv
publicvoid setTotalPage(int totalPage){ i%,
't
this.totalPage = totalPage; ZOpKi:\
} .2s^8 g O
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} B<HN$/
Od:-fw
|~PaCw8-ge
dZI["FeO&d
7B\Q5fLQ
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 FCWk8/
@#$(Cs*{]
个PageUtil,负责对Page对象进行构造: g-1j#V`5
java代码: @|bJMi
7upWM~H^
M"bG(a(6:
/*Created on 2005-4-14*/ &`m$Zzl;
package org.flyware.util.page; "z;R"sv\
h+A+>kC5
import org.apache.commons.logging.Log; L]u^$=rI
import org.apache.commons.logging.LogFactory; W0Y
,3;0
3^xq+{\)
/** 6:6A"A
* @author Joa ;r&Z?B$
* C"%B>e
*/ *'-t_F';
publicclass PageUtil { DEt!/a{X
Dln1 R[
privatestaticfinal Log logger = LogFactory.getLog |0?v4%g
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(PageUtil.class); }p?67y/
C&R U
/** $mE3 FJP>
* Use the origin page to create a new page )rt%.`
* @param page 5Pxx)F9]
* @param totalRecords 9I;~P &
* @return E*wG5]at
*/ v Y0ESc{
publicstatic Page createPage(Page page, int "Dc\w@`E 0
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totalRecords){ 2|d^#8)ZC
return createPage(page.getEveryPage(), `wQs$!a
R5%CK_
page.getCurrentPage(), totalRecords); i3Bpim.
} -mn/Yv
:#35mBe}k
/** '3Q~y"C+4
* the basic page utils not including exception dr+(C[=
XWQ `]m)
handler -2 >s#/%
* @param everyPage Y6Cm
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* @param currentPage FfrC/"N
* @param totalRecords dJ Q K|/
* @return page eEP{?F^I[
*/ #;W4$q
publicstatic Page createPage(int everyPage, int Us!ZQ#pP
@ =~k[o
currentPage, int totalRecords){ .P/0`A{&
everyPage = getEveryPage(everyPage); $u'"C|>8
currentPage = getCurrentPage(currentPage); B{D4.!a
int beginIndex = getBeginIndex(everyPage, 9+PAyI#w
wet[f {c
currentPage); &rD8ng+$
int totalPage = getTotalPage(everyPage, n%#3xoa
C;K+ITlJ
totalRecords); ge.>#1f}
boolean hasNextPage = hasNextPage(currentPage, la w$LL
bhIShk[
totalPage); {wj%WSQj/y
boolean hasPrePage = hasPrePage(currentPage); %.r\P@7/Q
=b>TF B=*N
returnnew Page(hasPrePage, hasNextPage, f\_PNZCc
everyPage, totalPage, Sw,*#98
currentPage, l~f3J$OkJ
zow8 Q6f
beginIndex); 'TH[Db'`I
} 5 QuRwu_
zGyRzxFN
privatestaticint getEveryPage(int everyPage){ *pSnEWwE
return everyPage == 0 ? 10 : everyPage; 3*2~#dh=
} ,f>9oOqqA
Z_4%Oi
privatestaticint getCurrentPage(int currentPage){ QOYMT( j
return currentPage == 0 ? 1 : currentPage; OG?7(
UJ
} 4:NMZ `~
S`zu.8%5
privatestaticint getBeginIndex(int everyPage, int y*{zX=]l<
:i?6#_2IC
currentPage){ WPNw")t!
return(currentPage - 1) * everyPage; WQ[nK5#
} =<p=?16
x
EFh^C.S8
privatestaticint getTotalPage(int everyPage, int 2p\xgAW?
/7Pqy2sgE
totalRecords){ JZ`h+fAt
int totalPage = 0; +~iiy;i(
*8?2+)5"
if(totalRecords % everyPage == 0) Uoe;=P@
totalPage = totalRecords / everyPage; rDbtT*vN
else 03v& k
totalPage = totalRecords / everyPage + 1 ; >| ,`E
WA43}CyAe
return totalPage; {G x=QNd
} y,|2hrj/0E
R@jMFh;
privatestaticboolean hasPrePage(int currentPage){ 0 {z8pNrc
return currentPage == 1 ? false : true; [O&}Qk
} U!r8}@
1_q!E~)
privatestaticboolean hasNextPage(int currentPage, -i{_$G8W/c
v9Ii8{ca|
int totalPage){ dt"/4wCO
return currentPage == totalPage || totalPage == JfWkg`LqL
'vVWUK956
0 ? false : true; s)]T"87H'_
} dV
:}
V.*M;T\i
&(Fm@ksh\
} *w(n%f
}vU/]0@,E
N6-7RoA+
"J+L]IC?AD
bH/4f93Nb
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。 "kFH*I+v
(i%bQZt^?
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 KqJln)7
sGhw23
做法如下: _d3Z~cH
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@Hx
LEGj
dFw+nGN
的信息,和一个结果集List: dL%*;
java代码: J~WT;s
$zCCeRP
W7uX
/*Created on 2005-6-13*/ K<5yjG8&
package com.adt.bo; _`;KmD&5
Ot-P
J
i
import java.util.List; &2XH.$Q
X\Zan$oi
import org.flyware.util.page.Page; ynM~&]fk#k
jXf@JxQ
/** B2]52Fg-"
* @author Joa LJ@(jO{z
*/ WM|G/'q
publicclass Result { N9G xJ6
Sdmz(R
private Page page; `B3-#!2X
t adeG
private List content; m85ZcyW1T
|s/N?/qi
/** Wfd`v
* The default constructor SF;\*]["f
*/ h.#:7d(g
public Result(){ Yz0fOX
super(); z4BU}`;b3t
} D`^wj FF
s(Gs?6}>T
/** SS%Bde&<{
* The constructor using fields 02[m{a-
* QAxy?m,'
* @param page Nm&'&L%Ch
* @param content O@@nGSc@
*/ $Xt""mlQ
public Result(Page page, List content){ ;yNY/
this.page = page; +|dLR*s
this.content = content; +%9Re5R
} vS~tr sI
s) s9Z,HY
/** ;6hoG(3
+
* @return Returns the content. J1O1! .
*/ {'+{ASpO!
publicList getContent(){ Ewkx4,`Ff
return content; RYvcuA)
} ?m~1b_@A{
x#SE%j?
/** d.w]\
* @return Returns the page. jG&HPVr
*/ REU&8J@k&?
public Page getPage(){ M}X `
return page; 30WOH
'n
} U5j4iz'
'L3MHTM>[
/** _XP}fx7$C
* @param content BhAT@%
* The content to set. /PSXuVtu5
*/ u8JH~b
public void setContent(List content){ |(W04Wp"@
this.content = content; %`s#p` Ol1
} L
/ PAC
{9 |*au(K
/** b7^q(}qE
* @param page HP*{1Q@5
* The page to set. *^;
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*/ aKW-(5<JW
publicvoid setPage(Page page){ pe,y'w{
this.page = page; M __S)
} ^NX;zc
} cX1?4e8
pFMjfWD,C
0OG
3#pE
40
u
tmC
V[%IU'{:
2. 编写业务逻辑接口,并实现它(UserManager, o`QH8
V!. Y M)B
UserManagerImpl) z"|jCdZGM
java代码: @^ta)Ev
}sqFvab<
=pmG.>Si
/*Created on 2005-7-15*/ a"Iu!$&N
package com.adt.service; ex~"M&^
hFycSu
import net.sf.hibernate.HibernateException; k
t!@}QP
]Q.S Is
import org.flyware.util.page.Page; *B@#A4f"
'-f` 5 X
import com.adt.bo.Result; ( -q0!]E
jT0iJ?d,!
/** a(fiW%eFb
* @author Joa '6\w4J(
*/ \>"Zn7
publicinterface UserManager { P5G0fq7
R(_WTs9x4
public Result listUser(Page page)throws ]==7P;_-
N@Ap|`Ei
HibernateException; IY!.j5q8
)L
"Dt_t
} !W&|kvT^
&'PLOyWw
Kn1u1@&Xd
vnbY^ASdw
'Q]Wk75
java代码: .&b c3cW
leSBR,C
uj%]+Llxv
/*Created on 2005-7-15*/ ODpAMt"
package com.adt.service.impl; 4\V/A+<W
d8
v9[4
import java.util.List; H%=;pD>o
2XUIC^<@s
import net.sf.hibernate.HibernateException; aRn""3[
oWDn_GnG`h
import org.flyware.util.page.Page; ~k@{b&
import org.flyware.util.page.PageUtil; LoJEchRK
tycVcr\(
import com.adt.bo.Result; d"3x11|
import com.adt.dao.UserDAO; `\ nKPj
import com.adt.exception.ObjectNotFoundException; (?T{^Hg
import com.adt.service.UserManager; X?r$o>db
QDK }e:4q
/** bFA
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* @author Joa y^X]q[-?
*/ h{~GzrL*
publicclass UserManagerImpl implements UserManager { vgNrHq&2q
?u{Mz9:?HT
private UserDAO userDAO; wB[
JFy"E
]d|M@v~c4
/** *ZRk)
* @param userDAO The userDAO to set. X,8Zn06M
*/ =b6G' O[
publicvoid setUserDAO(UserDAO userDAO){ :<
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this.userDAO = userDAO; n0':6*oGW
} `'(@"-L:7
fgo3Gy*#
/* (non-Javadoc) =@P(cFJ/
* @see com.adt.service.UserManager#listUser :.-KM7tDI1
ZWB3R
(org.flyware.util.page.Page) u!VrMH
*/ 0!axAvBV
public Result listUser(Page page)throws YAi@EvzCVy
/Vv)00
HibernateException, ObjectNotFoundException { &MrG ,/
int totalRecords = userDAO.getUserCount(); ^d9o \
if(totalRecords == 0) S =sL:FC
throw new ObjectNotFoundException !D
'A
M|.ykA<D
("userNotExist"); ~dsx|G?p
page = PageUtil.createPage(page, totalRecords); WUx2CK2N
List users = userDAO.getUserByPage(page); Us>n`Lj@
returnnew Result(page, users); PDh!B_+
} P^BSl7cT
tKi^0vE8
} Yka>r9wr
7B)@ aUj$
0|rdI,z
_ UF'Cf+Y
PB{5C*Y7^k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 gX5.u9%C\
eX^ F^(
询,接下来编写UserDAO的代码: cgQ2Wo7tCq
3. UserDAO 和 UserDAOImpl: URyY^+s
java代码: ~~,#<g[
1!ijRr
s*kSl:T@O
/*Created on 2005-7-15*/ d\ Xijy
package com.adt.dao; R"71)ob4
#W L>ha
v
import java.util.List; ixF
%BkPkQA
import org.flyware.util.page.Page; Hg[AulNna
G^\.xk]
import net.sf.hibernate.HibernateException; 0t00X/
I9cZZ`vs
/** rf2-owWN
* @author Joa P76QHBbl
*/ {/qq*0wa
publicinterface UserDAO extends BaseDAO { kQtnT7
Zu^J X/um
publicList getUserByName(String name)throws @0%^\Qf2
5'"9)#Ve
HibernateException; `vrLFPdO
]1KF3$n0
publicint getUserCount()throws HibernateException; x):h|/B
X>rv{@K bL
publicList getUserByPage(Page page)throws %R*-oQ1T
4p/d>DTiM
HibernateException; )u5+<OG}=
j1P#({z[
} ^WIGd"^
kT{d pGU9
cpBTi
Hz3KoO &
@EB2I+[
java代码: 4VfZw\^
H5p&dNO
M!b"c4|<
/*Created on 2005-7-15*/ x-=qlg&EI
package com.adt.dao.impl; THDyb9_g
R9lb<`
import java.util.List; $"x~p1P
[>U =P`
import org.flyware.util.page.Page; [cf!%3>53
.uu[MzMIu
import net.sf.hibernate.HibernateException; <Yy|.=6 D
import net.sf.hibernate.Query; SpX6PwM
f^k H[C
import com.adt.dao.UserDAO; A"~4|`W
"iTi+UZxe
/** $|bdeQPr\
* @author Joa _+2Jc}Yf
*/ 5\eM3w'd
public class UserDAOImpl extends BaseDAOHibernateImpl I Z{DR
O;?Nz:/q
implements UserDAO { )wueR5P
*b+~@o
/* (non-Javadoc) #Vi:-zyY
* @see com.adt.dao.UserDAO#getUserByName ORP-@-dap
^26}j uQ
(java.lang.String) As-xO~ +
*/ @fG'X
publicList getUserByName(String name)throws ._IBO; *@
ct![eWsuB
HibernateException { Ea\Khf]2
String querySentence = "FROM user in class Doc_rQYku
rGb<7b%
com.adt.po.User WHERE user.name=:name"; M|xs>+r*
Query query = getSession().createQuery w_]`)$9
s'JbG&T[J
(querySentence); 'WQ?%da
query.setParameter("name", name); Kk9W=vd
return query.list(); Yb;$z'
} @J UCXm
o-_H+p6a
/* (non-Javadoc) }*9mNE
* @see com.adt.dao.UserDAO#getUserCount() KoKd.%
*/ DA wUG
publicint getUserCount()throws HibernateException { A{Dy3tm=
int count = 0; ;"Q.c#pA$g
String querySentence = "SELECT count(*) FROM /U5!]7&gB
N>Q~WXvV#
user in class com.adt.po.User"; @\s*f7
Query query = getSession().createQuery -b$m<\0*
{~cM 6W]f
(querySentence); urK~]68
count = ((Integer)query.iterate().next d !=AS
r:-,qy
()).intValue(); hxe X6
return count; K|sk]2.
} f1,VbuS9I
]m<z
/* (non-Javadoc) r"xs?P&/$
* @see com.adt.dao.UserDAO#getUserByPage 33z^Q`MTC
S-%itrB*
(org.flyware.util.page.Page) $QB/n63
*/ -"uOh,G}
publicList getUserByPage(Page page)throws L-eO_tTh0
^i8"eF
HibernateException { :Fh#"<A&&
String querySentence = "FROM user in class ( we)0AxF'
^aR^M\38
com.adt.po.User"; Cm%|hk>fQ
Query query = getSession().createQuery qN\?cW'
'@dk3:3t
(querySentence); F_ -}GN%
query.setFirstResult(page.getBeginIndex()) )0?u_Z]w9
.setMaxResults(page.getEveryPage()); 7 >-(g+NF!
return query.list(); tE WolO[\
} $|m'~AmI
K( r@JW
} -BcnJK0
7!/!a*zg
9%Qlg4~<s
zmhL[1qj
O;+
sAt
至此,一个完整的分页程序完成。前台的只需要调用 wA\a ]X.
i F \H
userManager.listUser(page)即可得到一个Page对象和结果集对象 Qo\?(EM
suHisc*
的综合体,而传入的参数page对象则可以由前台传入,如果用 @Y !Jm
T~8kKw
webwork,甚至可以直接在配置文件中指定。 [JYy
B&m6N,
下面给出一个webwork调用示例: ~J HEr48
java代码: qs{wrem
GBY{O2!3u
\+j:d9?
/*Created on 2005-6-17*/ UM2yv6:/
package com.adt.action.user; ]Z?jo#F
4JRQ=T|P7I
import java.util.List; 'x6rU"e $J
bbT1p:RF
import org.apache.commons.logging.Log; YI>9C 76L
import org.apache.commons.logging.LogFactory; o .*t
import org.flyware.util.page.Page; {Z1KU8tp
CbwQbJ/v7
import com.adt.bo.Result; 4%#q.qI
import com.adt.service.UserService; 7%Ou6P$^fr
import com.opensymphony.xwork.Action; KW!+Ws
>XxHp
/** X?o6=)SC|
* @author Joa /ke[nr
*/ $[oRbH8g
publicclass ListUser implementsAction{ .bUj
2~R%_r+<
privatestaticfinal Log logger = LogFactory.getLog wLzV#8>
_nM 7SK
(ListUser.class); 9_O6Sl
<G'M/IR a
private UserService userService; 2fg
P
b=5ZfhIg[
private Page page; ZW4$Ks2]Y
tUt_Q;%yC
privateList users; Rg^ps
r
uIgo B
/* =RAojoN
* (non-Javadoc) WL?qulC}h1
* -@ra~li,yQ
* @see com.opensymphony.xwork.Action#execute() tSe[*V4{'
*/ qeb} ~FL"o
publicString execute()throwsException{ 'uF75C
Result result = userService.listUser(page); ~~=]_lwyK%
page = result.getPage(); h^
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users = result.getContent(); uAV7T /'
return SUCCESS; U }AIOtUw
} ^$X|Lq
34Cnbtq^
/** upZtVdd
* @return Returns the page. SSq4KFO1
*/ 2x<!>B
public Page getPage(){ Z;,G:@,
return page; Te`@{>
} r-*j"1 e
v^)B[e!
/** OL%}C*Zq
* @return Returns the users. r*dNta<
*/ ioEjbqD<
publicList getUsers(){ MkhD*\D
/
return users; 7&D)+{g
} BMqr YW
=XK}eQ_d
/** L|L|liWd
* @param page z~==7:Os
* The page to set. *[m:4\
*/ t{QQ;'
publicvoid setPage(Page page){ *l;S"}b*,_
this.page = page; ;xiwyfqgE
} $VB
dd~f
v~yw-}fk%
/** H%etYpD
* @param users {bR2S&=OmK
* The users to set. KVr9kcs
*/ \yZVn6GVr
publicvoid setUsers(List users){ ~#i2reG5
this.users = users; :U *8S\$
} S;jD@j\t&
u{h67N
/** Srz8sm;
* @param userService jvAjnh#
* The userService to set. Dy>6L79G
*/ =m F"D:s*
publicvoid setUserService(UserService userService){ Vo+.s#wN`h
this.userService = userService; RwYFBc
} %l14K_
} wu><a!3`=o
ZNM9@;7
Qe\vx1GRLH
idGn{f((f
/H"fycZ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ~\i(bFd)
F_9
4k
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 U#]J5'i
g1}:;VG=
么只需要: [7d(PEQL`
java代码: U\B9Ab
I.G[|[. Do
4hLk+ z<n
<?xml version="1.0"?> a/J Mg
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork KvEv0L<ky
F[SZwMf29
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 2O*At%CzW
U,Uy0s2r
1.0.dtd"> l@*$C&E
!=PH5jTY
<xwork> FU/:'/ L
4x(m.u@
<package name="user" extends="webwork- 1^*ogMe
ZOcpF1y
interceptors"> t!SxJB e
KXDnhVf
<!-- The default interceptor stack name iE
HWD.u
8/(}Wet
--> D_0sXIbg
<default-interceptor-ref FeMgn`q
1.k=ji$D0
name="myDefaultWebStack"/> nOd;Zw
y0(.6HI
<action name="listUser" $[?N^
5,s@K>9l;
class="com.adt.action.user.ListUser"> }2LWDQ;po
<param `h'l"3l
EyVu-4L:#
name="page.everyPage">10</param> {<@ud0A:\
<result ?A7 AVR
h U-FSdR
name="success">/user/user_list.jsp</result> ui,!_O .c
</action> ;Ivv4u
Z!~_#_Ugl
</package> )mf|3/o
\%Y`>x.
</xwork> GiX3c^V"1
p7-\a1P3
TP {\V>*Yz
21tv(x
e+-#/i*
J.XhP_aT
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 4gC(zJ
{[tmz;C
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 L~{(9J'(
#<"od '{U
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 \By_mw
keRLai7h
8Cp@k=
yc?L
OW0
c`\/]
我写的一个用于分页的类,用了泛型了,hoho ]
&" `
qQ^CSn98J
java代码: 2"Wq=qy\J
'_4apyq|
,M?8s2?
package com.intokr.util; g$#A'Du
x$` lQ%
import java.util.List; z"yW):X
D!Y@Og.
/** PkyX,mr#1
* 用于分页的类<br> h M7 SGEV
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Mz(?_7
* 3Fn}nek
* @version 0.01 y*X.DS 1(w
* @author cheng -ak.wwx\
*/ C=r`\W
public class Paginator<E> { O&aD]~|
privateint count = 0; // 总记录数 DoFe:+_U3
privateint p = 1; // 页编号 ,~38IIS>_
privateint num = 20; // 每页的记录数 #z&R9$
privateList<E> results = null; // 结果 bj@R[!ss
:Bt,.uNC
/** [Z2[Iy
* 结果总数 CSoVB[vS
*/ @fmp2!?6
publicint getCount(){ #tHYCSr]
return count; =dHdq D
} *bYU=RS
qF$y
p>|#
publicvoid setCount(int count){ d9S?dx
this.count = count; VT4>6u}
} YHom9&A
OqMdm~4B!j
/** -f ~1Id
* 本结果所在的页码,从1开始 =|Qxv`S1
* ga\s5
* @return Returns the pageNo. J`0dF<<{[y
*/ :TP4f
?FA
publicint getP(){ hM!g6\ w
return p; 6l2O>V
} *2-b&PQR{
9v;[T%%
/** @<$m`^H
* if(p<=0) p=1 {aV,h@>
* 6p&2A
* @param p ltkARc3
*/ H1q,w|O9j
publicvoid setP(int p){ I>l^lv&[+
if(p <= 0) X,G"#j^
p = 1; Z]{=Jy!F
this.p = p; 2^`k6V!
} ji4bz#/B0
f,6V#,
/** h {J io>
* 每页记录数量 2 f%+1uU
*/ q'y<UyT6
publicint getNum(){ seAPVzWUU
return num; WQN`y>1#@_
} .Ow8C
p>J@"?%^
/** (U$;0`
* if(num<1) num=1 xH`
VX-X3
*/ JQej$=*
publicvoid setNum(int num){ 6hR `sE
if(num < 1) A2L"&dl
num = 1; Z*b l J5YC
this.num = num; ~@Bw(!
} t OJyj49^a
sdB(sbSF
/** TUwX4X6m
* 获得总页数 e, 2/3jO
*/ 2/A*\
publicint getPageNum(){ Q;z!]hjBM
return(count - 1) / num + 1; JJg;X :p
} >L "+8N6
<2<2[F5Q%
/** ojm IEzsz
* 获得本页的开始编号,为 (p-1)*num+1 `Xeiz'~f8
*/ w8$>
2
publicint getStart(){ jy>?+hm?
return(p - 1) * num + 1; mqsAYzG
} `jOk6;Z[
FVL{KNW~i
/** kmu`sk"
* @return Returns the results. P {n*X
*/ L[nDjQn"
publicList<E> getResults(){ w 2U302TZ
return results; 0,@^<G8?
} ?tqJkL#
nnT#S
public void setResults(List<E> results){ @'M"c
q
this.results = results; \ %MsG
} KkpbZ7\@
,=G]tnsv^
public String toString(){ ~9#x=nU:+V
StringBuilder buff = new StringBuilder zv/dj04>
^LB]
(); ?D)$OCS
buff.append("{"); ]i0=3H2
buff.append("count:").append(count); xqY'-Hom
buff.append(",p:").append(p); GBpdj}2=
buff.append(",nump:").append(num); K*,,j\Q.
buff.append(",results:").append ,:'JJZg@
<Ist^h+o
(results); "zXrfn
buff.append("}"); +Q);t,
return buff.toString(); HYT~AO-!
} I
2OQ
IDos4nM27]
} 4<E <sD
BB69U
x6!Q''f7