Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 -6./bB g
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 M~/R1\'&j
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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 YPY'[j(p`n
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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 A_vf3 *q
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分页支持类: t:h~p-&QB
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java代码: 82bOiN15
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package com.javaeye.common.util; [8J/#!B
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import java.util.List; Vg+jF!\7
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publicclass PaginationSupport { `vijd(a?v
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publicfinalstaticint PAGESIZE = 30; Pd[&&!+gV
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privateint pageSize = PAGESIZE; !] -ET7
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privateList items; QE8aYPSFf
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privateint totalCount; b2Jgg&?G
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privateint[] indexes = newint[0]; #el i_Cxe
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privateint startIndex = 0; mJ3|UClPS
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public PaginationSupport(List items, int ?_+h+{/@B
dt efDsK
totalCount){ P}El#y#&
setPageSize(PAGESIZE); S1R:/9
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setTotalCount(totalCount); jnl3P[uQ
setItems(items); ;6?VkF
setStartIndex(0); )^C w
} \2K_"5
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public PaginationSupport(List items, int Y`x54_32
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totalCount, int startIndex){ o$=D`B
setPageSize(PAGESIZE); Y;L,}/[
setTotalCount(totalCount); )$Erfu
setItems(items); *c[X{
setStartIndex(startIndex); B tZycI
} <L72nwcK
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public PaginationSupport(List items, int "t{|e6
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totalCount, int pageSize, int startIndex){ {=Y.Z1E:
setPageSize(pageSize); $YmD;
setTotalCount(totalCount); V ?10O
setItems(items); V=@M!;'<
setStartIndex(startIndex); jtMN )TM
} Ier0F7]I
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publicList getItems(){ Z?vbe}pUM
return items; Dt9[uyP&
} J(\]3 9y
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publicvoid setItems(List items){ gX}(6RP_!
this.items = items; /uc*V6Xd
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} 2xchjU-
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publicint getPageSize(){ +=5Dt7/|
return pageSize; *o/Q#
} O>=D1no*
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publicvoid setPageSize(int pageSize){ QsaaA
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this.pageSize = pageSize; PTu~PVbp4
} ]#C;)Vy
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publicint getTotalCount(){ X0=#e54
return totalCount; l3sL!D1u
} t\hvhcbL
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publicvoid setTotalCount(int totalCount){ "]%.%$
if(totalCount > 0){ s
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this.totalCount = totalCount; F 8\nAX
int count = totalCount / @
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pageSize; !H`! KBW
if(totalCount % pageSize > 0) O\64)V
0
count++; D Hkmn
indexes = newint[count]; H!y%Fa Ti
for(int i = 0; i < count; i++){ r@_`ob RW;
indexes = pageSize * 1D42+cy
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i; v2>.+Eh#
} D\~*| J
}else{ Yg5m=Lis
this.totalCount = 0; OY'490
} Fm@G@W7,m
} 69U[kW&
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publicint[] getIndexes(){ T@PtO"r
return indexes; DwXzmp[qWH
} i-(^t1c
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publicvoid setIndexes(int[] indexes){ 6Q&R,"!$p
this.indexes = indexes; tBNkVh(c
} V9:h4]
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publicint getStartIndex(){ 7/.- dfEK
return startIndex; 6~Y-bn"%D5
} CwKo'PAJ
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publicvoid setStartIndex(int startIndex){ _ri1RK,
if(totalCount <= 0) Sb=cWn P
this.startIndex = 0; WN?1J4H
elseif(startIndex >= totalCount) {'W\~GnZ
this.startIndex = indexes g{&a|NU^
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[indexes.length - 1]; m^dKww
elseif(startIndex < 0) R v61*F4
this.startIndex = 0; Py$*c
else{ Xp<RGp7E
this.startIndex = indexes @ \ip?=
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[startIndex / pageSize]; d[+ xLa
} i]{M G'tg
} `A5^D
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publicint getNextIndex(){ .YquOCc(
int nextIndex = getStartIndex() + JV|GEn\@N
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pageSize; WDr'w'
if(nextIndex >= totalCount) MIPmsEdBi
return getStartIndex(); X%7Y\|
else IS0RhtGy/
return nextIndex; MR$Bl"d
} eiB5 8b3
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publicint getPreviousIndex(){ 6 flc
int previousIndex = getStartIndex() - 8M m,a
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pageSize; ~ g$Pb[V
if(previousIndex < 0) {.tUn`j6V
return0; I^'kt[P'FZ
else SS@F:5),
return previousIndex; x0wy3+GZc
} CW>f;
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} HqXaT6#/
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抽象业务类 H aI
java代码: 9 aT#7B
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/** s
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* Created on 2005-7-12 u=
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*/ ;3NA,JA#Y
package com.javaeye.common.business; N ?0T3-/K
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import java.io.Serializable; ZK4/o
import java.util.List; 2bU3*m^M
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import org.hibernate.Criteria; ipfiarT~)
import org.hibernate.HibernateException; lTsl=
import org.hibernate.Session; I0oM\~#
import org.hibernate.criterion.DetachedCriteria; :i+Tf~k{
import org.hibernate.criterion.Projections; qCOe,$\1/
import wYZFW'5p
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org.springframework.orm.hibernate3.HibernateCallback; R+IT)2
import ?fcQd6-}
U}(*}Ut
org.springframework.orm.hibernate3.support.HibernateDaoS y)?Sn
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upport; N8;/Zd;^
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import com.javaeye.common.util.PaginationSupport; EI6K0{'&X
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public abstract class AbstractManager extends =xFw4D9
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HibernateDaoSupport { <<K G S
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privateboolean cacheQueries = false; IBr?6_\%"4
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privateString queryCacheRegion; D_@WB.eL
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publicvoid setCacheQueries(boolean ]cLO-A
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cacheQueries){ r`}')2
this.cacheQueries = cacheQueries; %JmSCjt`G
} uG@Nubdwuy
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publicvoid setQueryCacheRegion(String U7(84k\j
v)>R)bzqe
queryCacheRegion){ z/(^E8F
this.queryCacheRegion = q-O=Em <*
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queryCacheRegion; ]Ec\!,54u
} ^6`"f
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publicvoid save(finalObject entity){ -Zd0[& ']
getHibernateTemplate().save(entity); sA=WU(4^
} cLn&b}8'
) *ocX)AE
publicvoid persist(finalObject entity){ ^=@L(;Y
getHibernateTemplate().save(entity); <m:8%]%M6
} S*<+vIo
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publicvoid update(finalObject entity){ jh\L)a*
getHibernateTemplate().update(entity); \zCT""'i
} Mq;m+{B
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publicvoid delete(finalObject entity){ ^%tmHDNL.
getHibernateTemplate().delete(entity); jC7`_;>=
} ~p^&`FA
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publicObject load(finalClass entity, zsnXPRF
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@~2
finalSerializable id){ &y"e|aE
return getHibernateTemplate().load }DiMt4!ZC!
+ HvEiY
(entity, id); -:]_DbF
} JG-\~'9
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publicObject get(finalClass entity, [;yEG$)K
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finalSerializable id){ v;4l*)$)
return getHibernateTemplate().get iX,|;J|]
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(entity, id); KLi&TmIB
} D/wX
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publicList findAll(finalClass entity){ ;^VLx)q
return getHibernateTemplate().find("from M-Gl".*f
q))rlMo
" + entity.getName()); #_)<~
} CtiTXDc_
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publicList findByNamedQuery(finalString iOk^RDG+
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namedQuery){ GSck^o2{
return getHibernateTemplate stn/
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().findByNamedQuery(namedQuery); >S\D+1PV
} xx[XwN;
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publicList findByNamedQuery(finalString query, i#c1ZC
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finalObject parameter){ K)!yOa'fH
return getHibernateTemplate h$3o]~t
op!8\rM<e
().findByNamedQuery(query, parameter); V}c3}'_U]
} h+ixl#:
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publicList findByNamedQuery(finalString query, [N]5)n
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finalObject[] parameters){ F\LAw#IJ
return getHibernateTemplate "N'|N.,
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().findByNamedQuery(query, parameters); -%R3YU3
} N$cm;G=]
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publicList find(finalString query){ T["(wPrt
return getHibernateTemplate().find ,mkXUW
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(query); M1UabqQ
} ~=xiMB;oH
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publicList find(finalString query, finalObject k&TZ
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parameter){ 'E_M,Y
return getHibernateTemplate().find !'yCB9]O
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(query, parameter); =t@8Y`9w
} H> Y0R
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public PaginationSupport findPageByCriteria yHYqJ|t
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(final DetachedCriteria detachedCriteria){ hrT!S
return findPageByCriteria |r|<cc#
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }02#[vg
} ZeB"k)FI>
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public PaginationSupport findPageByCriteria B4uJT~,7>
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(final DetachedCriteria detachedCriteria, finalint y~16o
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startIndex){ 3c%dErch
return findPageByCriteria >0^oC[ B
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(detachedCriteria, PaginationSupport.PAGESIZE, CP5vo-/)-
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startIndex); ,RA;X
} 9n\b!*x
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public PaginationSupport findPageByCriteria |8m2i1XG
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(final DetachedCriteria detachedCriteria, finalint 2cnyq$4k
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pageSize, {Yt@H
finalint startIndex){ W##~gqZ/
return(PaginationSupport) G8sxg&bf{
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getHibernateTemplate().execute(new HibernateCallback(){ vJ&g3ky
publicObject doInHibernate f3[/zcm;
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(Session session)throws HibernateException { F"G]afI9+
Criteria criteria = Exu5|0AAE
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detachedCriteria.getExecutableCriteria(session); _NwB7@ e
int totalCount = KscugX*x
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((Integer) criteria.setProjection(Projections.rowCount QDHTP|2e
,NA _pvH)
()).uniqueResult()).intValue(); >>>&{>}!
criteria.setProjection QTC-W2t]
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(null); Yg~$1b@
List items = t[|aM-F&>
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criteria.setFirstResult(startIndex).setMaxResults 9w"kxAN
Y!1x,"O'H
(pageSize).list(); +[lv
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PaginationSupport ps = i(9 5=t(
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new PaginationSupport(items, totalCount, pageSize, ;WP%)Z
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startIndex); Mhwuh`v%
return ps; .7`c(9<
} qhQeQ
}, true); lx H3a :gm
} ?c6`p3p3L
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public List findAllByCriteria(final gK#G8V-,
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DetachedCriteria detachedCriteria){ d7U%Q8?wUR
return(List) getHibernateTemplate D=^|6}
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().execute(new HibernateCallback(){ VJoobu1h
publicObject doInHibernate 3[UB3F4K
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(Session session)throws HibernateException { fgW>~m.W
Criteria criteria = 1:j[p=Q&
-"}mmTa*<
detachedCriteria.getExecutableCriteria(session); 9l&4mt;+&<
return criteria.list(); <?E~Qc t
} |.~0Ulk,
}, true); gc[BP>tl\
} H\^zp5/
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public int getCountByCriteria(final C_rA'Hy
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DetachedCriteria detachedCriteria){ $8;`6o`
Integer count = (Integer) N_Q\+x}zq
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getHibernateTemplate().execute(new HibernateCallback(){ ?Mj@;O9>'
publicObject doInHibernate B4kJ 7Pdny
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(Session session)throws HibernateException { CGCI3Z'
Criteria criteria = ZmKxs^5S
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detachedCriteria.getExecutableCriteria(session); uk<JV*R=
return v$]eCj'
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criteria.setProjection(Projections.rowCount EpdSsfDP
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()).uniqueResult(); RS9mAeX4h
} qf?X:9Wt
}, true); F\BD7W
return count.intValue(); 7]pi .1i
} T^1]|P
} +-d)/h.7
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用户在web层构造查询条件detachedCriteria,和可选的 |x/00XhS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 M.h8Kr!.
IWs)n1D*]
PaginationSupport的实例ps。 *c{X\!YBh
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ps.getItems()得到已分页好的结果集 ,#blY~h8^
ps.getIndexes()得到分页索引的数组 K'u66%wAL
ps.getTotalCount()得到总结果数 ZMn~QU_5
ps.getStartIndex()当前分页索引 )a0%62
ps.getNextIndex()下一页索引 :I/i"g7<
ps.getPreviousIndex()上一页索引 0k):OVfm=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 y~-dQ7r
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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 o5`LLVif5y
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4}!;<
一下代码重构了。 oJ`cefcWo
Nub)]S>_/t
我把原本我的做法也提供出来供大家讨论吧: {ZR>`'^:
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首先,为了实现分页查询,我封装了一个Page类: ml\2%07
java代码: VyWPg7}e
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/*Created on 2005-4-14*/ o'auCa,N
package org.flyware.util.page; +x_9IvaW&?
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/** u{d\3-]/
* @author Joa Y}UVC|Ef
* lk`,s
*/ Uk@'[_1z
publicclass Page { 8 bpYop7
L
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/** imply if the page has previous page */ Wv4o:_}
privateboolean hasPrePage; l
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+:jx{*}jo
/** imply if the page has next page */ g+ P
privateboolean hasNextPage; P{ HYZg
(>usa||
/** the number of every page */ ,"U_oa3
privateint everyPage; KCc7u8
[t }\8^y
/** the total page number */ >Ndck2@
privateint totalPage; x!RpRq9
( {}Z
'
/** the number of current page */ || 0n%"h>i
privateint currentPage; x-%4-)
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/** the begin index of the records by the current #BLmT-cl
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query */ LzE$z,
privateint beginIndex; 4t e QG
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/** The default constructor */ ZA {T0:
public Page(){ >uR0Xs;V
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} Fh0cOp(
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/** construct the page by everyPage k?7V#QW(
* @param everyPage M`u&-6
* */ #ssSs]zl
public Page(int everyPage){ BK;Gh0mp
this.everyPage = everyPage; bjCO@t
} Pua|Z
x
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/** The whole constructor */ & cV$`L
public Page(boolean hasPrePage, boolean hasNextPage, t'{IE!_
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int everyPage, int totalPage, Y5,[udF:O
int currentPage, int beginIndex){ Md[M}d8
this.hasPrePage = hasPrePage; 6)j4-
this.hasNextPage = hasNextPage; /|MHZ$Y9w?
this.everyPage = everyPage; :plN<8
this.totalPage = totalPage; INjr$'*
this.currentPage = currentPage; l\t\DX"s_
this.beginIndex = beginIndex; bbe$6x wi
} HY!R |
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/** |9'`;4W
* @return b<bj5m4fz>
* Returns the beginIndex. [Zxv&$SQ
*/ =9yh<'583
publicint getBeginIndex(){ cN3!wE
return beginIndex; w 8BSY
} hb="J349
19j"Zxdg Y
/** 3LW_qX
* @param beginIndex ` G-V
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* The beginIndex to set.
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*/ !%X#;{
publicvoid setBeginIndex(int beginIndex){ tN1xZW:
this.beginIndex = beginIndex; `p'682x I
} |w].*c}Z
h
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/** m xEniy
* @return -\[H>)z]RB
* Returns the currentPage. q/#pol
*/ C116c"
publicint getCurrentPage(){ sOqT*gwr:
return currentPage; {|{;:_.>
}
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/** iu.v8I;<
* @param currentPage Us2IeR
* The currentPage to set. Lm3~< vP1e
*/ 8}K^o>J&K
publicvoid setCurrentPage(int currentPage){ |}><)}
this.currentPage = currentPage; zI,z <-
} 0PD=/fh[
SceK$
/** `n?Rxhkwp
* @return *$Z,kZ^^
* Returns the everyPage. Xti.yQx\
*/ +l hJ8&
publicint getEveryPage(){ 1I?`3N
return everyPage; Jo''yrJpB
} ]{|
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4$+1&+@ ]
/** U8zCV*ag
* @param everyPage 19b@QgfWpb
* The everyPage to set. Vbv)C3ezD
*/ =Hbf()cN)
publicvoid setEveryPage(int everyPage){ Ozg,6&3ji
this.everyPage = everyPage; J9-n3o
} ,@kLH"a0
YeS5%?Fk
/** Ao+6^z_
* @return N*+ L'bO
* Returns the hasNextPage. o~7D=d?R
*/ 0^vz /y1c
publicboolean getHasNextPage(){ ]P/i}R:
return hasNextPage; 4sq](!A
} [/o BjiBA
ik#ti=.
/** :nOI|\rC
* @param hasNextPage y*
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* The hasNextPage to set. IIN,Da;hD
*/ jO-T1P']Y
publicvoid setHasNextPage(boolean hasNextPage){ C8W_f( i~
this.hasNextPage = hasNextPage; iG#92e4
} sJ{r+wY
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/** Ma4eu8
* @return _Q 'f^Kj
* Returns the hasPrePage. NxSSRv^rx
*/ =h xyR;
publicboolean getHasPrePage(){ ^WF_IH&
return hasPrePage; lid0
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} $xCJ5M4
:k-@w5(
/** W[R`],x`
* @param hasPrePage &kcmkRRG
* The hasPrePage to set. &@FufpPw/
*/ znDpg{U(
publicvoid setHasPrePage(boolean hasPrePage){ $4*gi&
this.hasPrePage = hasPrePage; LP !d|X
} =KAN|5yn
5g.w"0MkY
/** R;pIi/yDRe
* @return Returns the totalPage. T(,@]=d,DD
* '14 86q@[$
*/ kZhd^H.
publicint getTotalPage(){ [+8*}03
return totalPage; FY-eoq0O3
} v_WF.sb~
J\>/J%
/** C\Z5%2<Z
* @param totalPage ]"^p}:
* The totalPage to set. 4 L
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*/ D^a(|L3;
publicvoid setTotalPage(int totalPage){ gLY15v4?
this.totalPage = totalPage; _8ks`O#}
} !x\\# 9
kGL3*x
} ;.<HpDfG_
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0|i|z!N>
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+=d=
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 OG_v[ C5
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个PageUtil,负责对Page对象进行构造:
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java代码: $Yp.BE<}
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dt>9mF q
/*Created on 2005-4-14*/ \j-:5M#m
package org.flyware.util.page; A`Rs
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import org.apache.commons.logging.Log; l_8ibLyo
import org.apache.commons.logging.LogFactory; $~j9{*]5
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/** :."6 g)T
* @author Joa uRYq.`v,
* ic4hO>p&
*/ Dd,i^,4Gj
publicclass PageUtil { 0P!Fci/t
vP+qwvpGr
privatestaticfinal Log logger = LogFactory.getLog 9g'6zB
kBnb9'.A1
(PageUtil.class); ;g;1<?
[
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/** 0LSJQ9\p
* Use the origin page to create a new page f! )yE`4-
* @param page pSEaE9AX%
* @param totalRecords VR%*8=
* @return Z6Z/Y()4Tl
*/ O(9*VoD
publicstatic Page createPage(Page page, int }f% Qk0^
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totalRecords){ d0f(U k
return createPage(page.getEveryPage(), Z c#Jb
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page.getCurrentPage(), totalRecords); vS[\j
} 4Ss y (gt
!&`\MD>;~R
/** 2- (}=N
* the basic page utils not including exception (
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&3xda1H
handler Kb-m
* @param everyPage {*r!oD!'
* @param currentPage <^'IC9D]
* @param totalRecords f^F"e'1
* @return page &p*rEs
*/ 6D`.v@
publicstatic Page createPage(int everyPage, int Q`4Ia<5B
O*x~a;?G
currentPage, int totalRecords){ wlslG^^(!
everyPage = getEveryPage(everyPage); s8qpK; O
currentPage = getCurrentPage(currentPage); 4d}n0b\d
int beginIndex = getBeginIndex(everyPage, x{GFCy7
%K06owV(S)
currentPage); wuXH'
int totalPage = getTotalPage(everyPage, E9t8SclV
u6IM~kk>5
totalRecords); vq-;wdq?2
boolean hasNextPage = hasNextPage(currentPage, B<$6Dj%L
gw%L M7yQR
totalPage);
klY, @
boolean hasPrePage = hasPrePage(currentPage); =4U$9jo!;
'YYT1H)
returnnew Page(hasPrePage, hasNextPage, N=~DSsw
everyPage, totalPage, `Hv"^o
currentPage, F[0~{*/|G
/^I!)|At
beginIndex); e eyZ$n
} y&\t72C$Fi
[9Tnp]q
privatestaticint getEveryPage(int everyPage){ cf*~Gx_l
return everyPage == 0 ? 10 : everyPage; EU'rdG*t/R
} nLPd]%78>
#SjCKQ~
privatestaticint getCurrentPage(int currentPage){ [D<(xr&N%
return currentPage == 0 ? 1 : currentPage; vBM<M3
} "-AFWWKtx
EaH/Gg3
privatestaticint getBeginIndex(int everyPage, int pL> Yx>
+bb-uoZf
currentPage){ !|9k&o
return(currentPage - 1) * everyPage; { ~(XO@;b
} k)8*d{ *
Rt5Xqz\6i
privatestaticint getTotalPage(int everyPage, int <;jg/
4$ah~E>,t
totalRecords){ 62G%.'7
int totalPage = 0; 73{<;z}i
W3^^aD-
if(totalRecords % everyPage == 0) h7m$P^=U
totalPage = totalRecords / everyPage; 1}p:]/;
else ?nE9@G5Gc
totalPage = totalRecords / everyPage + 1 ; 2n#H%&^?a
uBC#4cX`D*
return totalPage; 1 .o0"
} 8)83j6VF
XB:E<I'q!3
privatestaticboolean hasPrePage(int currentPage){ N
f}ZG
return currentPage == 1 ? false : true; NpbZt;%t
} ygK,t*T20
Z]5xy_La
privatestaticboolean hasNextPage(int currentPage, PfhKomt"
9OlJC[
int totalPage){ SaRn>n\
return currentPage == totalPage || totalPage == "tDB[?
w7\
\m9
0 ? false : true; UjyrmQf
} d*@K5?O.
^$rqyWZYp
Q]dKyMSSA
} 1p<*11
J$`5KbT3
wX!0KxR/Z
Mi}k>5VT
VmXXj6l&
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。 y~VLa
3S%/>)k
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 `?d`
#)Ck
C0ORBp
做法如下: )L_@l5l
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !|mzu1S
':f,RG
的信息,和一个结果集List: SI=7$8T5=5
java代码: YjPj#57+
dMI G2log
n9Vr*RKM)
/*Created on 2005-6-13*/ r=]$>&
package com.adt.bo; X2YBZA
bJw{ U.
import java.util.List; B f.- 5
}z2[w@M
import org.flyware.util.page.Page; dChMjaix
Pa?C-Xn^
/** :8]y*j
* @author Joa ?0:=+%.
*/ @S&QxE^
publicclass Result { :+8qtIytKX
Bt(nm>Ng
private Page page; sdN1BV2
m<J:6^H@
private List content; Lx|0G $
e^N}(Kpy
/** `:Oje
* The default constructor N).'>
*/ w/9%C(w6
public Result(){ N_l_^yD
super(); hzA+,
} $M$-c{>s
~{pds
/** .d?LRf
* The constructor using fields }q,d JE
* drbim8!q~
* @param page 1I40N[PE)
* @param content fT
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*/ @E>I<j,D
public Result(Page page, List content){ g|tclBx
this.page = page; $KP;9
this.content = content; B#3Q4c$
} dfh 1^Go
xl@~K^c]
/** _ne
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* @return Returns the content. {vQ:4O!:
*/ bHQ) :W
publicList getContent(){ |OuIQhoE
return content; @gw8r[
} JoD@e[(
PZI6{KOis
/** 6MLjU1
* @return Returns the page. `Q[NrOqe"
*/ oc#hAjB.
public Page getPage(){ 2UxmKp[
return page; yI^7sf7k
} yq[@Cw
-lR7
@S
/** |7${E^u
* @param content $#(j2sL1
* The content to set. KN>h*eze
*/ Pc<0kQg
public void setContent(List content){ I+31:#d
this.content = content; DWN9_*{
} /Pg)@*~
+,TrJg
/** _(I)C`8m
* @param page "8~PfLJ+
* The page to set. %/qwqo`Q
*/ hE<Sm*HU
publicvoid setPage(Page page){ amQTPNI
this.page = page; l=x(
} Ejnk\ 8:
} C~C`K%7
:zNNtv iA
#T@k(Bz{L
!Uv>>MCr
|dDKO
2. 编写业务逻辑接口,并实现它(UserManager, =^ \?{oV
f>|<5zm#<
UserManagerImpl) zg$ag4%Qgg
java代码: wuW{2+)B
e1%kW1Z9
^aQ&.q
/*Created on 2005-7-15*/ z4;@"B
package com.adt.service; /)`]p1c1%w
X4Pm&ol
import net.sf.hibernate.HibernateException; i0zrXaKV
K\59vtga
import org.flyware.util.page.Page; UtQCTNjC{
i"pOYZW1
import com.adt.bo.Result; {m@tt{%
/Z,hQ>/
/** nF<xJs
* @author Joa B|,d
*/ xA`j:zn'j
publicinterface UserManager { uGm?e]7Hx<
0s\ -iub=d
public Result listUser(Page page)throws 4nGt*0Er
`S.I,<&
HibernateException; h=JW^\?\]
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} q]VB}nO
g"(@+\XZH"
f=u +G
~*9Ue@
_N)&<'lB<
java代码: B2'TRXIm1U
D$*o}*mb
cc:$$_'L
/*Created on 2005-7-15*/ 08D:2 z1z
package com.adt.service.impl; ]!~?j3-k Q
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import java.util.List; Y_EEnx&>i
>d
*`K
import net.sf.hibernate.HibernateException; 57 Bx-
1uCF9P
ai
import org.flyware.util.page.Page; /wl]kGF
import org.flyware.util.page.PageUtil; r4DHALu#)
3vjOfr`
import com.adt.bo.Result;
3bR%#G%
import com.adt.dao.UserDAO; VaGQre
import com.adt.exception.ObjectNotFoundException; SMJRoK3
import com.adt.service.UserManager; nMfR<%r
A~lc`m-
/** 41s\^'^&
* @author Joa EtaKo}!A}
*/ f}p`<z
publicclass UserManagerImpl implements UserManager { OK8Ho"
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private UserDAO userDAO; O`"~AY&
gIusp917
/** ",J&UTUh
* @param userDAO The userDAO to set. :#35mBe}k
*/ '3Q~y"C+4
publicvoid setUserDAO(UserDAO userDAO){ ~zG)<S"q
this.userDAO = userDAO; Yf~Kzv1]*
} QB!_z4UJ_;
u'Q82l&Y
/* (non-Javadoc) F:q8.^HTJ
* @see com.adt.service.UserManager#listUser NsSZ?ky
UnP<`z#
(org.flyware.util.page.Page) *hJWuMfY,
*/ ]Y!Fz<-;P
public Result listUser(Page page)throws *78c2`)[
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HibernateException, ObjectNotFoundException { ) \T H'
int totalRecords = userDAO.getUserCount(); b;5j awG
if(totalRecords == 0) mH0OW
throw new ObjectNotFoundException T!B\ixt6
5`+9<8V
("userNotExist"); /4 OmnE;
page = PageUtil.createPage(page, totalRecords); (dD7"zQ
List users = userDAO.getUserByPage(page); ge.>#1f}
returnnew Result(page, users); J -Lynvqm
} 2[uFAgf@
m"'LT0nur
} ( $2M"n
DB-79U %W
*($,ay$&H
G9LWnyQt
P5oS 1iu*
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 6Aq]I$
~%g,Uypi
询,接下来编写UserDAO的代码: gh\u@#$8
3. UserDAO 和 UserDAOImpl: *jWh4F,
java代码: @KU;'th
&Tuj`DL
:q*w_*w
/*Created on 2005-7-15*/ ng9e)lU~*b
package com.adt.dao; Fpn*]x
fW+"Kuw
import java.util.List; ej&.tNvq
tP*Kt'4W
import org.flyware.util.page.Page; }u3|w0~c)
B=~y(Mb
import net.sf.hibernate.HibernateException; T1.U (::
Y
z&!0Hfd
/** aK;OzB)
* @author Joa G~(\N?2
*/ N<a%l J
publicinterface UserDAO extends BaseDAO { d94k
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publicList getUserByName(String name)throws JZ`h+fAt
JfSe;
v
HibernateException; W}TP(~x'N
8P-ay<6
publicint getUserCount()throws HibernateException; iJ^}{-
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publicList getUserByPage(Page page)throws Kmaz"6A
_v 0iH
HibernateException; 7:pc%Ksq
OzrIiahz/
} YSt*uOZK
Z^%a 1>`
MJ?t{=
cpP}NJb0;%
B!x#|vGXL
java代码: z=U+FHdh/-
C 4C/
9]l I?j]o
/*Created on 2005-7-15*/ xO>z
)3A
package com.adt.dao.impl; iD|~$<9o
ZJZSt% r
import java.util.List; OHBCanZZ,
Y0|){&PCt
import org.flyware.util.page.Page; IS(F_< .
jGz~}&B
import net.sf.hibernate.HibernateException; K=0xR*ll5
import net.sf.hibernate.Query; TY %zw6 #p
DoQ^caa@
import com.adt.dao.UserDAO; JZ-@za6u
k6ry"W3
/** U?f-/@fc
* @author Joa KqJln)7
*/ 7<e}5nA/
public class UserDAOImpl extends BaseDAOHibernateImpl bHRn}K+<}c
^0| :
implements UserDAO { \&kj#)JYA
F}45.CrD
/* (non-Javadoc) yXDjM2oR/2
* @see com.adt.dao.UserDAO#getUserByName 2yn"K|
Bh=t%#y|`
(java.lang.String) P7=`P
*/ uXFI7vV6P
publicList getUserByName(String name)throws &}e>JgBe0
6Y]P7j
HibernateException { duEXp]f!
String querySentence = "FROM user in class "y"oV[`
,P}7e)3
com.adt.po.User WHERE user.name=:name"; ed',\+.uB
Query query = getSession().createQuery K1J |\!o
zCo$YP#5_
(querySentence); vFdI?(c-
query.setParameter("name", name); iZfZF
return query.list(); eEVB
} ,v})
d"?"(Q_8n
/* (non-Javadoc) KZ[TW,Gw
* @see com.adt.dao.UserDAO#getUserCount() #2U# h-vI
*/ V;SV0~&
publicint getUserCount()throws HibernateException { 80lhhqRC
int count = 0; P-2DBNB7
String querySentence = "SELECT count(*) FROM tDL.+6/
auAz>6L
user in class com.adt.po.User"; )-5e Iy
Query query = getSession().createQuery ~L<"]V+B
;303fS
(querySentence); bR"4:b>K
count = ((Integer)query.iterate().next -JEPh!oTt
dpq(=s`s
()).intValue(); O@@nGSc@
return count; $Xt""mlQ
} ;yNY/
AFL'Ox]0
/* (non-Javadoc) HN367j2 e
* @see com.adt.dao.UserDAO#getUserByPage PQlA(v+S
&aIFtlC
(org.flyware.util.page.Page) ;6hoG(3
+
*/ BV@q@C
publicList getUserByPage(Page page)throws dh6kj-^;Cf
LqD7SJ}/f
HibernateException { ,}W|cm>
String querySentence = "FROM user in class DTA$,1JuD
9>-6Y
com.adt.po.User"; R[\1Kk(Zo
Query query = getSession().createQuery Cx~;oWZ
\='LR!_
(querySentence); i ?pd|J
query.setFirstResult(page.getBeginIndex()) >F7HKwg}Z
.setMaxResults(page.getEveryPage()); ,rN$ah$CL
return query.list(); "aKlvK:77
} EMe1!)
.
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} ]}'bRq*]
(|AZO!
vde!k_,wZ
|)>+&
xk
hC"'cUrcN
至此,一个完整的分页程序完成。前台的只需要调用 .9ZK@xM&?
8 0nu^_
userManager.listUser(page)即可得到一个Page对象和结果集对象 RTd,bi*
0#'MR.,
的综合体,而传入的参数page对象则可以由前台传入,如果用 +@fEw
9C?SEbC
webwork,甚至可以直接在配置文件中指定。 :+\sKEzL
:D3:`P>,c
下面给出一个webwork调用示例: 4|%Y09"lv
java代码: MkGQ
O{3X`xAf
1O0)+9T82
/*Created on 2005-6-17*/ rd%uc~/
package com.adt.action.user; 40
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tmC
_nz_.w0H9
import java.util.List; go=xx.WJ
)d3C1Pd>
import org.apache.commons.logging.Log; z"|jCdZGM
import org.apache.commons.logging.LogFactory; PtQ[({d3R
import org.flyware.util.page.Page; Jo[&y,
X4\T=Q?uLx
import com.adt.bo.Result; X6B,Mply
import com.adt.service.UserService; QPp31o.!5
import com.opensymphony.xwork.Action; "h1ek*(?<
~~&Bp_9QXN
/** /#{~aCOi)
* @author Joa X)j%v\#`U
*/ ktfxb<%
publicclass ListUser implementsAction{ s=:LS
wpN [0^M-0
privatestaticfinal Log logger = LogFactory.getLog 1Ci^e7|?
cr0/.Zv)
(ListUser.class); C[TjcHoA
x{!+4W;S
private UserService userService; wO!>kc<
so.}WU
private Page page; )AieO-4*
=v?V
privateList users; :rufnmsP<U
!W&|kvT^
/* =s:kC`O
* (non-Javadoc) Sa)L=5Nr
* Hxac#(,7
* @see com.opensymphony.xwork.Action#execute() elKp?YN
*/ rcLF:gd]E
publicString execute()throwsException{ |Om][z
Result result = userService.listUser(page); p[|V7K'Z
page = result.getPage(); @$p6w
users = result.getContent(); JB5%\
return SUCCESS; {EoZ}I
} T$FKn
]{|l4e4P
/** pox;NdX7
* @return Returns the page. g=v'[JPd
*/ x) %"i)
public Page getPage(){ XF3lS#pt
return page; 1p/_U?H:|
} eUu<q/FUMj
(yEU9R$I"
/** $_HyE%F#
* @return Returns the users. QDK }e:4q
*/ GX.a!XQ@!
publicList getUsers(){ n
sN n>{
return users; (yT&&_zY4
} K-.%1d@$y
8 f~M6
/** C^]UK
* @param page $S?xB$
* The page to set. IK4(r /
*/ @YS,)U)4S
publicvoid setPage(Page page){ .[:WMCc\
this.page = page; o {q8An)
} (YPG4:[
b9b`%9/L
/** `'(@"-L:7
* @param users YWANBM(v+
* The users to set. cI7a TLC"s
*/ "6%qi qt
publicvoid setUsers(List users){ L&5zr_
this.users = users; oq>jCOVh
} h^{aG ])
p[!9 objU
/** ^}z:FI
* @param userService 8y?q)y9h
* The userService to set. {@"
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*/ #7J3,EV
publicvoid setUserService(UserService userService){ *li5/=UC5*
this.userService = userService; !D
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} IMy!8$\u
} Y\(?&7Aax
yaI jXv
=k!F`H`/%'
$z@nT.x5
?U*s H2F
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, ; ?,'jI*1
`V[ hE
r|
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 +sd':vE
Tkh?F5l
么只需要: kRiZ6mn
java代码: lqoVfj'6M
7:C2xC
. Eb=KG
<?xml version="1.0"?> Ei@al>.\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ef:Zi_o
bde6
;=oM
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _ [hVGCSB
c
8|&Q
1.0.dtd"> {\k:?w4
lI[O!VuKc
<xwork> #W L>ha
v
H)+wkR!~
<package name="user" extends="webwork- lIatM@gU
Hg[AulNna
interceptors"> ).r04)/
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<!-- The default interceptor stack name n{%[G2.A
UO>S2u
--> G4f%=Z
<default-interceptor-ref =I)Ex)
9q<?xO
name="myDefaultWebStack"/> ur/:aI
$K~ t'wr
<action name="listUser" g6q67m<h
5'"9)#Ve
class="com.adt.action.user.ListUser"> onUF@3V
<param g
_u
=Wl}Pgo!
name="page.everyPage">10</param> H|B4.z
<result ;e^`r;]
\;Q:a
/ur9
name="success">/user/user_list.jsp</result> 3C;nC?]K
</action> Yg3emn|a
dmE.yVI"O
</package> gA DF
Lc13PTz>>g
</xwork> *8xMe
|1"n\4$
t9m08K:Y
R;2
Z~P
LD)P.
f
p3{ 3[fDx
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 2z027P-Q
2t"&>1
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。 nfjwWDH
[NIaWI,>
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 HFrwf{J
$2gZpO|
S-KHot ?
iwT
PJGK|
{Zy)p%j8
我写的一个用于分页的类,用了泛型了,hoho jr=erVHK
:Z5Twb3h
java代码: H{j
jA+0
DS1_hbk
@a}jnl(2
package com.intokr.util;
Vi_6O;
5]yby"Z?}
import java.util.List; [}t^+^/
Y|96K2BR
/** V`XtGTx
* 用于分页的类<br> L9":=
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "s5[w+,R
* r5S5;jL%t
* @version 0.01 fjm(C#^-
* @author cheng l's*HExR
*/ `5CuH
public class Paginator<E> { ]KE"|}B
privateint count = 0; // 总记录数 % #$K P
privateint p = 1; // 页编号 !U8n=A#,-
privateint num = 20; // 每页的记录数 X(*MHBd
privateList<E> results = null; // 结果 !omf>CW;ud
#[.aj2
/** "8sB,$
* 结果总数 @J UCXm
*/ o-_H+p6a
publicint getCount(){ 8%Hc%T[RnT
return count; !{%BfZX<&
} qaZQ1<e
pDV8B/{
publicvoid setCount(int count){ Vx*O^cM
this.count = count; 5Gw B1}q
} ::R5F4
H^r;,Q$9
/** @\s*f7
* 本结果所在的页码,从1开始 -b$m<\0*
* y0_z_S#gO
* @return Returns the pageNo. 3P2x%G p
*/ xfK@tLEZ-1
publicint getP(){ ?3=y]Vb+
return p; iininITOS{
} '
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<b#1L
/** H=v=)cUe[
* if(p<=0) p=1 )
o`ep{<t
* 9mRP%c#(
* @param p hYB3tT
*/ !\Vc#dslt
publicvoid setP(int p){ ^Cy=L]
if(p <= 0) -"uOh,G}
p = 1; ^n~bx*f
this.p = p; 1=z6m7@'-
} SS*3Qx:[
IC6r?
/** k$3Iv"gbx
* 每页记录数量 =M`Xu#eRk
*/ / ?Hq
publicint getNum(){ t0.71(
return num; =M9;`EmC
} ]e6$ ={
W:8pmI
/** AjD?_DPc
* if(num<1) num=1 ^?5HagA
*/ c"lblt5
publicvoid setNum(int num){ q1pB~eg5
if(num < 1) e?_uJh"
num = 1; V
`7(75
this.num = num; zS*vKyye>
} U%)-_
*`z
oLIgj,k{*
/** Qv6-,6<
* 获得总页数 bXi(]5
*/ z-N
N(G+
publicint getPageNum(){ rT_J6F5J
return(count - 1) / num + 1; Q6;bORN
} @%BsQm
QjOY1Xze
/** ~J HEr48
* 获得本页的开始编号,为 (p-1)*num+1 S S fNI>
*/ ^h!}jvqE
publicint getStart(){ |[!7^tU*
return(p - 1) * num + 1; `Wd4d2aLG
} !v.
<H]s)
y({lE3P
/** 08+\fT [
* @return Returns the results. ipyc(u6Z5
*/ xnxNc5$oE
publicList<E> getResults(){ I]a [Ngj
return results; {Z1KU8tp
} A1n4R
Rj3ad 3z'E
public void setResults(List<E> results){ Qs ysy
this.results = results; *!pn6OJ"Q}
} gx8i|]
P*n/qj8h
public String toString(){ NMS+'GRW
StringBuilder buff = new StringBuilder mVEIHzk2b
kB.CeG]tk
(); YJ|U|[
buff.append("{"); s|I$c;>
buff.append("count:").append(count); 86);0EBX
buff.append(",p:").append(p); jq%}=-%KE
buff.append(",nump:").append(num); =b, m31
buff.append(",results:").append DMOP*;Uk
\-SC-c
(results); 7AlL,&+
buff.append("}"); %aV~RB#
return buff.toString(); Tp|>(~;ai
} M%WO
(3~^zwA
} sX-@
>%l
OZA^L;#>
[^W
+^3V