Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (j>`+F5f
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 EWJB/iED
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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 <MEm+8e/s6
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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 TTG=7x:3
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。 }P.s
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分页支持类: O+!4KNN.-
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java代码: w&@tP^`
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package com.javaeye.common.util; b GSj?t9/
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import java.util.List; :r{-:
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publicclass PaginationSupport { YusmMsN?
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publicfinalstaticint PAGESIZE = 30; 1
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privateint pageSize = PAGESIZE; )d[n-Si
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privateList items; )
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privateint totalCount; =U84*HAv
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privateint[] indexes = newint[0]; (6c/)MH
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privateint startIndex = 0; Vu_oxL}
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public PaginationSupport(List items, int t<Sa;[+
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totalCount){ Xf ^_y(?
setPageSize(PAGESIZE); ttr`
setTotalCount(totalCount); !ak760*A
setItems(items); e!Z}aOeE
setStartIndex(0); M_0f{
} RA a1^Qb
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public PaginationSupport(List items, int bV:<%l]
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totalCount, int startIndex){ RH,x);J|
setPageSize(PAGESIZE); tIn`L6b
setTotalCount(totalCount); CeU=A9
setItems(items); 9qa/f[G
setStartIndex(startIndex); m p_7$#{l
} a2?@OJ
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public PaginationSupport(List items, int !,$K;L
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totalCount, int pageSize, int startIndex){ iB99.,o-&
setPageSize(pageSize); (e_<~+E
setTotalCount(totalCount); = ~s+<9c]
setItems(items); UNSXr`9
setStartIndex(startIndex); C}9GrIi
} Z|KDi
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publicList getItems(){ #6~KO7}
return items; 7.2G}O6$
} /IcGJ&;
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publicvoid setItems(List items){ ~(*tcs]hY
this.items = items; +DQUL|\
} 8@ f!,!Wn
}e|cszNRd
publicint getPageSize(){ Z=$-S(>J
return pageSize; &g}P)xr
} d@^%fVhG
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publicvoid setPageSize(int pageSize){ 1tO96t^d%
this.pageSize = pageSize; v?8i;[
} PcbhylKd
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publicint getTotalCount(){ jD<xpD
return totalCount; 6
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} 5{W Aw !
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publicvoid setTotalCount(int totalCount){ hrJ(] [8
if(totalCount > 0){ Yt =)=n
this.totalCount = totalCount; t<c7%i#Od
int count = totalCount / ObZhQ.&
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pageSize; x?A<X2
if(totalCount % pageSize > 0) L!Tvz(_7f6
count++; byP< !p*
indexes = newint[count]; q%M~gp1
for(int i = 0; i < count; i++){ W'Ew!]Q3
indexes = pageSize * bD/ZKvg
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i; &tbAXU5$
} #oiU|>3Y
}else{ W=g'Xu!|!2
this.totalCount = 0; 9:g]DIL
} M^OYQf
} ^6{op3R_
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publicint[] getIndexes(){ 6.tA$#6HP
return indexes; gT=pO`a
} zqt%x?l
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publicvoid setIndexes(int[] indexes){ DO{otn9<
this.indexes = indexes; y5c\\e
} ,%A|:T]
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publicint getStartIndex(){ |_g7k2oLY
return startIndex; EF$ASNh"
} Q3hSWXq'
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publicvoid setStartIndex(int startIndex){ &'zc2
if(totalCount <= 0) t%e<]2-8
this.startIndex = 0; ]Hl{(v\HO
elseif(startIndex >= totalCount) :B=Gb8?
this.startIndex = indexes K@:omT
.*`]x
[indexes.length - 1]; >h:'Z*9
elseif(startIndex < 0) ]Ue
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this.startIndex = 0; V=&M\58
else{ f`;w@gR`=
this.startIndex = indexes bbjEQby
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[startIndex / pageSize]; SAitufS
} "~.4z,ha
} Yh^8
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publicint getNextIndex(){ $"(
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int nextIndex = getStartIndex() + 0=U|7%dOL
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pageSize; a_0I)'
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if(nextIndex >= totalCount) w2s06`g
return getStartIndex(); u^MRKLn
else 0#=xUk#LP`
return nextIndex; dg~lz8 0
} ~a4Y8r
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publicint getPreviousIndex(){ pl[@U<8aw
int previousIndex = getStartIndex() - F
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}%PK %/ zI
pageSize; o_b3G
if(previousIndex < 0) |ssl0/nk
return0; >r\GB#\5
else #^]vhnbN
return previousIndex; _OjZ>j<B.
} .Mb0++% W
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} =Yl ea,S
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抽象业务类 Nr]Fh
java代码: Sx
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/** ^>ir&$
* Created on 2005-7-12 ia_@fQ
*/ ,W[J@4.
package com.javaeye.common.business; DrioBb@
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import java.io.Serializable; EN[T3 Y
import java.util.List; } LC
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import org.hibernate.Criteria; 2ry@<88
import org.hibernate.HibernateException; 'oY#a9~Z{
import org.hibernate.Session; <'UGYY\wg0
import org.hibernate.criterion.DetachedCriteria; {PxFG<^U
import org.hibernate.criterion.Projections; J;^ PM:6
import {K"hlu[
H"UJBO>$
org.springframework.orm.hibernate3.HibernateCallback; f@hM ^%
import uY>M3h#qx
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org.springframework.orm.hibernate3.support.HibernateDaoS `)cH(Rj
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upport; XKws_
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import com.javaeye.common.util.PaginationSupport; Z|x|8 !D
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public abstract class AbstractManager extends /RqWrpzx@
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HibernateDaoSupport { ~ffT}q7^
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privateboolean cacheQueries = false; JrY*K|YdW
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privateString queryCacheRegion; -3)jUzD
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publicvoid setCacheQueries(boolean $Z;/Sh
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cacheQueries){ itirh"[
this.cacheQueries = cacheQueries; M.s'~S7y
} 1d FuoX
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publicvoid setQueryCacheRegion(String ,G}i:7
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queryCacheRegion){ 0mUVa=)D
this.queryCacheRegion = ZfqN4
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queryCacheRegion; hchG\i
} m#8[")a$"
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publicvoid save(finalObject entity){ X|Y(* $?D7
getHibernateTemplate().save(entity); K y%lu^
} 9-{=m+|b
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publicvoid persist(finalObject entity){ m Rw0R{
getHibernateTemplate().save(entity); ~I+MuI[
} s^eiym P
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publicvoid update(finalObject entity){ R^/SBrWve
getHibernateTemplate().update(entity); LYRpd
} 4RtAwB
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publicvoid delete(finalObject entity){ /qIl)+M
getHibernateTemplate().delete(entity); RfTGTz@H
} 7g"u)L&32
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publicObject load(finalClass entity, >god++,o
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finalSerializable id){ \298SH(!7
return getHibernateTemplate().load ; iia?f1
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(entity, id); RhHm[aN
} U3V5Jor#
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publicObject get(finalClass entity, Px=@Tw N,
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finalSerializable id){ qJdlZW<
return getHibernateTemplate().get +K'Hr:(
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(entity, id); i}DS+~8v
} [A,^F0:h
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publicList findAll(finalClass entity){ iI IXv
return getHibernateTemplate().find("from 'v V7@@
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" + entity.getName()); *l+Dbm,u
} + tMf&BZ
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publicList findByNamedQuery(finalString s||" } l
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namedQuery){ PY^#hC5:
return getHibernateTemplate ^HJ?k:u
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().findByNamedQuery(namedQuery); {k)gDJU
} |sReHt2)d
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publicList findByNamedQuery(finalString query, \4>,L_O
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finalObject parameter){ /!?LBtqy
return getHibernateTemplate *$<W"@%^J
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().findByNamedQuery(query, parameter); }LT&BNZj
} dg24h7|]
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publicList findByNamedQuery(finalString query, (6S'wb
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finalObject[] parameters){ c lB K
return getHibernateTemplate ccHf+=
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().findByNamedQuery(query, parameters); ">oySo.B?
} T^1
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publicList find(finalString query){ aZWj52
return getHibernateTemplate().find cQK-Euum
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(query); xmvE*q"9]
} HYfGu1j?X
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publicList find(finalString query, finalObject @vt.Db
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nq
parameter){ DpT9"?g7
return getHibernateTemplate().find C_Ewu*T7
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(query, parameter); 4KM-$h,4O
} PW5]+ |#
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public PaginationSupport findPageByCriteria P0n1I7|
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(final DetachedCriteria detachedCriteria){ VLez<Id9(
return findPageByCriteria !#c'|
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }4A] x`3
} zsg\|=P
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public PaginationSupport findPageByCriteria gJ
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(final DetachedCriteria detachedCriteria, finalint G](4!G&
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startIndex){ . 5(YL8d
return findPageByCriteria K& #il
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(detachedCriteria, PaginationSupport.PAGESIZE, SO$Af!S:bB
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startIndex); 6Wu*zY_+
} e73=*~kfR
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public PaginationSupport findPageByCriteria _}R[mr/
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(final DetachedCriteria detachedCriteria, finalint 6:ettdj
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pageSize, m4mE7Wn.3
finalint startIndex){ ^+_rv
return(PaginationSupport) |C[!A
q!$s<n
getHibernateTemplate().execute(new HibernateCallback(){ +OE!Uqnt
publicObject doInHibernate 94"+l@K
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(Session session)throws HibernateException { 7Y5 r3a}%
Criteria criteria = {zwH3)|Hn
ngo> ^9/8
detachedCriteria.getExecutableCriteria(session); n)e2?
int totalCount = nkW})LyB\
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#
((Integer) criteria.setProjection(Projections.rowCount wjA
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()).uniqueResult()).intValue(); H7zN|NdNw
criteria.setProjection 'hpOpIsHa
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(null); K-0=#6?y4
List items = Xz_WFLq4
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criteria.setFirstResult(startIndex).setMaxResults paqGW]
$DY#04Je\=
(pageSize).list(); Jo5B mh0
PaginationSupport ps = U#jz5<r
@/z\p7e
new PaginationSupport(items, totalCount, pageSize, M@Th^yF+8H
v(1 [n]y
startIndex); *f[5rr4
return ps; Mog>W&U
} [,o:nry'a
}, true); ,Z
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} 5h5izA'0'
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public List findAllByCriteria(final 1Bj.MQ^
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DetachedCriteria detachedCriteria){ lsz3'!%Y)
return(List) getHibernateTemplate Rx-\B$G
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().execute(new HibernateCallback(){ |N)Ik8
publicObject doInHibernate *~#I5s\s!
my (@~'
(Session session)throws HibernateException { b] 5weS-<
Criteria criteria = R#T-o,m
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detachedCriteria.getExecutableCriteria(session); $}9jv3>)
return criteria.list(); |[SHpcq>
} s L^+$Mq6
}, true); Cv**iW
} g)Lf^
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public int getCountByCriteria(final w*F[[*j@.
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DetachedCriteria detachedCriteria){ pY31qhoZ.
Integer count = (Integer) dGUP|O
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getHibernateTemplate().execute(new HibernateCallback(){ #])"1fk
publicObject doInHibernate z`{sD]
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(Session session)throws HibernateException { _Mw3>GNl
Criteria criteria = OoB|Eh|),
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detachedCriteria.getExecutableCriteria(session); IW~R{ ]6
return TM)INo^
j4$nr=d.6
criteria.setProjection(Projections.rowCount PLCm\Oh$l
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()).uniqueResult(); +kL7"
} r w?wi}}gn
}, true); 6jq*lnA%
return count.intValue(); aU!}j'5Q
} ^ZwZze:2
} ^'`b\$km-0
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用户在web层构造查询条件detachedCriteria,和可选的 H*=cw<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 hb`9Vn\-E
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PaginationSupport的实例ps。 Z@bgJL83
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ps.getItems()得到已分页好的结果集 m
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ps.getIndexes()得到分页索引的数组 JW>k8QjyN
ps.getTotalCount()得到总结果数 CIW4E
ps.getStartIndex()当前分页索引 8E%LhA.
ps.getNextIndex()下一页索引 (?z?/4>7<
ps.getPreviousIndex()上一页索引 @%4'2b
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,GSiSn
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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 #-L0.z(
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一下代码重构了。 j7}mh
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我把原本我的做法也提供出来供大家讨论吧: zluq2r
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首先,为了实现分页查询,我封装了一个Page类: ,rB(WKU
java代码: /YJo"\7
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/*Created on 2005-4-14*/ Ao K9=F}
package org.flyware.util.page; $kUB%\`
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/** hK?GIbRZ
* @author Joa "r^RfZ;
* <B6md
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*/ - Jaee,P
publicclass Page { ZF7n]LgSc&
g QBS#NY
/** imply if the page has previous page */ T+Yv5l
privateboolean hasPrePage; dz^HN`AlzC
}qWnn>h9xv
/** imply if the page has next page */ KI9Pw]]{-
privateboolean hasNextPage; 9PB%v.t5y
9vRLM*9|
/** the number of every page */ c.>f,vtcn
privateint everyPage; >Na. C(DZ
&M|rRd~*
/** the total page number */ ^G!cv
privateint totalPage; mV}bQ^*?Z
xp|1yud
/** the number of current page */ ^Mq/Cf_T
privateint currentPage; gC$_yd6m
L
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/** the begin index of the records by the current By1Tum+I1
c7CYulm
query */ .gO|=E"
privateint beginIndex; J!Z6$VERy
%R GZu\p
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/** The default constructor */ 0>Y3xNb
public Page(){ DuC#tDP
K~:SLCv
E%
} 4)iP%%JH
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/** construct the page by everyPage "}()/
* @param everyPage qc(e3x
* */ c/$].VG0
public Page(int everyPage){ jf)cDj2
this.everyPage = everyPage; ^\PRzY
} ';R]`vWFe
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/** The whole constructor */ 2TGND-(j
public Page(boolean hasPrePage, boolean hasNextPage, x-i,v"8
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int everyPage, int totalPage, P5my]4|x
int currentPage, int beginIndex){ "G%S
m")
this.hasPrePage = hasPrePage; ,$`}Rf<
this.hasNextPage = hasNextPage; oG)T>L[&
this.everyPage = everyPage; %U{6 `m
this.totalPage = totalPage; +2MF#{ tS
this.currentPage = currentPage; EMnz;/dMt
this.beginIndex = beginIndex; l~$)>?ZD
} ;bwBd:Y
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/** h;q&B9
* @return %ddH4Q/p
* Returns the beginIndex. n[>hJ6
*/ |47t+[b
publicint getBeginIndex(){ ^p(aZj3k
return beginIndex; QtfL'su:
} [pU(z'caS
g=mKTk
/** /)[-5n{
* @param beginIndex $7YZ;=~B
* The beginIndex to set. gw)z*3]~s
*/ bIm4s
publicvoid setBeginIndex(int beginIndex){ 8(`e\)%l0
this.beginIndex = beginIndex; PxYK)n9&
} '=nmdqP
zWo
/** @7}XBg[pI
* @return 0d2RB^"i
* Returns the currentPage. Rir0^XqG
*/ |ufT)+:
publicint getCurrentPage(){ >V8!OaY5n
return currentPage; -aBhN~
} g@ J F
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/** OGcdv{,P
* @param currentPage qGq]E`O
* The currentPage to set. 25Ee+&&%
*/ G-i2#S
publicvoid setCurrentPage(int currentPage){ g5U,
this.currentPage = currentPage; MR|A_e^x
} t,LK92?
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/** XR",.3LD
* @return Pfs_tu
* Returns the everyPage. yW?-Z[
*/ M gP|'H3\
publicint getEveryPage(){ B^9C}QB
return everyPage; Sm[#L`eqW
} > 3&
(}F@0WYT^O
/** F3V:B.C
* @param everyPage }c||$
* The everyPage to set. N5)H(<}
*/ AAfhh5i
publicvoid setEveryPage(int everyPage){ wmV=GV8 d
this.everyPage = everyPage; MMk9rBf
} 2Bi]t%<{
i-w<5pGnf
/** lZ5-lf4
* @return ^XeJZkLEB
* Returns the hasNextPage. ^5MM<73
*/ Z:^<NdKe
publicboolean getHasNextPage(){ ,Gy,bcv{
return hasNextPage; ts&\JbL
} 8p829
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/** +s_a{iMVP
* @param hasNextPage Zbl*U(KU?
* The hasNextPage to set. *0oa2fz%
*/ *DcIC]ao[
publicvoid setHasNextPage(boolean hasNextPage){ AHr^G'
this.hasNextPage = hasNextPage; hgYFR6VH
} `6-flc0r
BO}IN#
/** EO(l?Fgw]$
* @return ?r=`Kl
* Returns the hasPrePage. -hfDf{QN
*/ wL3BgCxqDL
publicboolean getHasPrePage(){ gLSI?
return hasPrePage; _"F=4`lJ
} 8~qpOQX^V
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/** 6Jy%4]wK
* @param hasPrePage ZuWhgnp
* The hasPrePage to set. e+#Oj
*/ }JOz,SQHP
publicvoid setHasPrePage(boolean hasPrePage){ >=rniHs=?7
this.hasPrePage = hasPrePage; iuqJPW^}
} ^xk4HF
;s~xS*(C
/** ZwxEcs+UM
* @return Returns the totalPage. OWz{WV.
* R4)l4rnO
*/ 6`7`herE}
publicint getTotalPage(){ _\+0e:Ae
return totalPage; CBdr1
} K~]Xx~F
9*JxP%8T~X
/** fFC9:9<
* @param totalPage \3(s&K\Y6\
* The totalPage to set. V@LBy1z
*/ 08@4u
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publicvoid setTotalPage(int totalPage){ .rg "(I
this.totalPage = totalPage; O>f*D+A-
} rv)Eg53Q
r_ m|?U
%
} W@GU;Nr
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[GM!@6U
ZJ)>gV
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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 N1E9w:T`
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个PageUtil,负责对Page对象进行构造: 4`5W] J]6
java代码: ZHwN3
3>5gh8!-
J#w=Z>oz <
/*Created on 2005-4-14*/ `nII@ !
package org.flyware.util.page; K\RMX?YsP
C<QpUJ`k
import org.apache.commons.logging.Log; 7!o#pt7
import org.apache.commons.logging.LogFactory; ho#<?rh_
rWJRoGk/
/** (.z0.0W
* @author Joa wko9tdC=U
* Z[RifqaBby
*/ pi;fu
publicclass PageUtil { ]We0 RD"+
t
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{[F
privatestaticfinal Log logger = LogFactory.getLog $Y$s*h_-/<
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(PageUtil.class); j$u
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/** cjLA7I.O
* Use the origin page to create a new page \ z*<^ONq
* @param page pxbuZ9w2Q
* @param totalRecords 1_xkGc-z<
* @return 4
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*/ u3 +]3!BQ
publicstatic Page createPage(Page page, int ok-q9dM
J| 46i
totalRecords){ 2c,w
4rK
return createPage(page.getEveryPage(), Q^Vch(`&P
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page.getCurrentPage(), totalRecords); %0u5d$b q
} bLggh]Fh
Mu" vj*F
/** <X5V]f
* the basic page utils not including exception _s=<Y^l%x
/K,@{__JP
handler |e+r~).4B
* @param everyPage su60j^e*
* @param currentPage EcR[b@YI
* @param totalRecords t1#f*G5
* @return page k9y/.Mu
*/ \WUCm.w6\%
publicstatic Page createPage(int everyPage, int )>rYp
)
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currentPage, int totalRecords){ H]dN'c-
everyPage = getEveryPage(everyPage); Cb|R
currentPage = getCurrentPage(currentPage); 'o8,XBv-
int beginIndex = getBeginIndex(everyPage, ARJtE@s6Y
+,ld;NM{
currentPage); 2C_I3S~U
int totalPage = getTotalPage(everyPage, d|
{<SRAI
}6__E;h#J
totalRecords); 6il+hz2&lH
boolean hasNextPage = hasNextPage(currentPage, !cO<N~0*5x
)Ps<u- V
totalPage); grd
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boolean hasPrePage = hasPrePage(currentPage); .D=#HEshk
b3=XWzK5
returnnew Page(hasPrePage, hasNextPage, v9D[|4
everyPage, totalPage, c)QOgXv
currentPage, .?F`H[^)^u
Hc0V4NHCaL
beginIndex); x;7p75Wm
} <Lle1=qQ
@a]`C
$6
privatestaticint getEveryPage(int everyPage){ }V+&o\4
return everyPage == 0 ? 10 : everyPage; M7gqoJM'Q
} m}m|(;T
{X\FS
privatestaticint getCurrentPage(int currentPage){ |z)7XK
return currentPage == 0 ? 1 : currentPage; O4W2X@
} 'Te'wh=Y
|L)qH"Eo
privatestaticint getBeginIndex(int everyPage, int kgX"I ?>d
?`SBGN;
currentPage){ y0t-e
return(currentPage - 1) * everyPage; x}7Xd P.2$
} taSYR$VJ
aTLr%D:Ka
privatestaticint getTotalPage(int everyPage, int %A@U7gqc
%8"Aq
totalRecords){ y$|OE%S
int totalPage = 0; y= 1(o3(
,ce$y4%(
if(totalRecords % everyPage == 0) (jh0cy}|]
totalPage = totalRecords / everyPage; cn
;2&
else ;sSRv9Xb
totalPage = totalRecords / everyPage + 1 ; \D! I"mr
g+k
yvI7o
return totalPage; VB+y9$Y'
} WZ@$bf}f0
0mT.J~}1v
privatestaticboolean hasPrePage(int currentPage){ ]@msjz'
return currentPage == 1 ? false : true; ZN`I4Ak
} 04E#d.o'
gn${@y?
privatestaticboolean hasNextPage(int currentPage, @%As>X<3t
,xC@@>f
int totalPage){ =NL(L
return currentPage == totalPage || totalPage == k'd=|U;(FV
T!H }^v
0 ? false : true; 4V5h1/JPm
} Nu%MXu+
sTYA
<(o) * Zmo
} z`y^o*qc]
yLvU@V@~
Z1+1>|-iW
S?(/~Vb%
vQ
DlS1L
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。 eq36mIo
lLL) S
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 yKOC1( ~
j1$s^ -9
做法如下: 2o`L^^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v1s0kdR,>
Al}%r85
的信息,和一个结果集List: Ykj+D7rA:
java代码:
qmGLc~M0
EYKV}`
RMxFo\TK;
/*Created on 2005-6-13*/ K!SFS
package com.adt.bo; y$HV;%G{26
NB)22 %
import java.util.List; yUFT9bD
,S=ur%
import org.flyware.util.page.Page; Md1ePp]
a"X9cU[
/** BP0*`TY
* @author Joa s\
YHT.O?
*/ hdH}4W
publicclass Result { /.[78:G\,
hW-?j&yJ?
private Page page; e:RgCDWL
XRWy#Pj
private List content; agPTY{;
10e~Yc
/** 1ihdH1rg[
* The default constructor [-JU(:Rh
*/ zM|Y
X<
public Result(){ C.9l${QU
super(); =E-V-?N\
} ]9NA3U7F
`KmM*_a
/** ~~3 BV,
* The constructor using fields xEqr3(
* R"qxT.P(
* @param page `"qSr%|
* @param content nHF%PH#|o
*/ IkJ-*vI6
public Result(Page page, List content){ 2umgF
this.page = page; 96S#Q*6+R
this.content = content; S/7?6y~
} UB|}+WA3
nK9?|@S*'
/** o",J{
* @return Returns the content. _ "H&
*/ Ex}hk!
publicList getContent(){ E4N{;'
return content; h_K!ch}
} JWvL
Hn!13+fS
/** <GO 5}>}p8
* @return Returns the page. Q}:#Hz?U
*/ 5?1:RE(1
public Page getPage(){ &`Ek-b!7
return page; =^`?O* /;
} ^ah9:}Ll
xh9Os <
/** q!\4|KF~
* @param content bGe@yXId5
* The content to set. .V`N^H:l
*/ o0:RsODl
public void setContent(List content){ L/2,r*LNx$
this.content = content; Ipyr+7/zJ
} m>ApN@n
gX!-s*{E
/** wOs t).
* @param page #8qhl
* The page to set. U/9_:
*/ \*5${[
publicvoid setPage(Page page){ x /E<@?*:
this.page = page; %{;1i
} 7HM%Cd
} 7FGi+
4Bz:n
M#;"7Qg
`D={l29H
/mCE=
2. 编写业务逻辑接口,并实现它(UserManager, i-gN<8\v
G#nZ%qQ:I
UserManagerImpl) ~X!Z+Vg
java代码: _mc-CZ
~Y/o9x0
0*yD
/*Created on 2005-7-15*/ cZlDdr%
package com.adt.service; Lv m"!!
)uu1AbT+e
import net.sf.hibernate.HibernateException; 9vI<\
Xa
= 4 wf
import org.flyware.util.page.Page; ?Es(pwJB
SZ(]su:
import com.adt.bo.Result; (]N- HN]v
L(+I
/** U;#9^<^
* @author Joa T1#r>3c\
*/ ZGj ^,? a
publicinterface UserManager { NWS3-iZ|8
< wi9
public Result listUser(Page page)throws m6Mko2
;9$71E
HibernateException; '|^x[8^
BnUWg ^E
} W!t =9i
Bht! +
WJj5dqatV
R,dbq4xkl
U'k 0;
java代码: fs\A(]`$
M`)/^S9
a]nK!;>$
/*Created on 2005-7-15*/ 1Y'NG<d_
package com.adt.service.impl; Mqv[7.|
h0a|R4J
import java.util.List; "Tz'j}< 9C
xM)6'= x6
import net.sf.hibernate.HibernateException; J"~!jrzBh(
y4)iL?!J~
import org.flyware.util.page.Page; M>[e1y>7
import org.flyware.util.page.PageUtil; z"P/Geb:O
`3yK<-
import com.adt.bo.Result; nM|Cv
import com.adt.dao.UserDAO; oju,2kpH7#
import com.adt.exception.ObjectNotFoundException; %y_{?|+
import com.adt.service.UserManager; TyhO+;
GRh430V[
/** 50""n7I<%
* @author Joa H)+QkQb}
*/ w)C5XX30;
publicclass UserManagerImpl implements UserManager { /V
GI@"^v
uH]oHh!}j
private UserDAO userDAO; c{
([U
rXP~k]tC
/** CorV!H4
* @param userDAO The userDAO to set. F:N8{puq5
*/ vb6kr?-i*
publicvoid setUserDAO(UserDAO userDAO){ i&YWutG
this.userDAO = userDAO; l"-Z#[
} o$Ju\(Y$<+
m~0Kos%^*b
/* (non-Javadoc) Z C<+BKS
* @see com.adt.service.UserManager#listUser G>Hg0u0!,
$b(CN+#
(org.flyware.util.page.Page) rCUGaf~
*/ g%<n9AUl
public Result listUser(Page page)throws ]f_`w81[
h0$Y;=YA
HibernateException, ObjectNotFoundException { 6EeO\Qj{
int totalRecords = userDAO.getUserCount(); eG7Yyz+t$
if(totalRecords == 0) 9l(T>B2a
throw new ObjectNotFoundException vUCmm<y
;5DDV6
("userNotExist"); aW-6$=W
page = PageUtil.createPage(page, totalRecords); Wdi`ZE
List users = userDAO.getUserByPage(page); 0SDnMij&bf
returnnew Result(page, users); z]7 /Gc,j
} [5!dO\-[
(9R;-3vY:S
} Gk]ZP31u
t{s*,X\b
>,[@SF%
q=}1ud}1
DD2K>1A1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .+,U9e:%
"9 f+F
询,接下来编写UserDAO的代码: 6$[7hlE
3. UserDAO 和 UserDAOImpl: U*b7 Pxq;
java代码: Z?xRSi2~7
IVY)pS"pR"
xHMFYt+0$G
/*Created on 2005-7-15*/ |kP utB
package com.adt.dao; u"4B5D
Evd|_ W-
import java.util.List; hH HQmK<r
axpZ`BUc
import org.flyware.util.page.Page; )+R n[MMp
@S=9@3m{w;
import net.sf.hibernate.HibernateException; qV6WT&)T
hJsP;y:@Lm
/** w@<II-9L)<
* @author Joa $1g1Bn
*/ C!|LGzs0
publicinterface UserDAO extends BaseDAO { YZ`SF"Bd(
tj$[szo
publicList getUserByName(String name)throws s&Y"a,|Z
kg
8Dn
HibernateException; -Caj>K
JQ6M,O
publicint getUserCount()throws HibernateException; hGkJ$QT
kRc+OsY9
publicList getUserByPage(Page page)throws 5VJe6i9;
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HibernateException; Ulx]4;uzf
fbU3-L?
} lLDZ#'&An
[}]yJ+)
rlD!%gG2x
n}j6gN! O
9!
/kyyU
java代码: uZZRFioX|
I}m20|vv
x Ek8oc
/*Created on 2005-7-15*/ a eeor
package com.adt.dao.impl; MM_:2 ^P)
+D:8r|evH
import java.util.List; Rq%Kw> {&
Q2D!Agq=D
import org.flyware.util.page.Page; xhOoZ-
tM^4K r~o,
import net.sf.hibernate.HibernateException; 5|nc^
12
import net.sf.hibernate.Query; <l$ d>,
X.#)CB0c1Q
import com.adt.dao.UserDAO; P6R_W
RFyMRE!?
/** #,u|*O:
* @author Joa z V\+za,
*/ t2s/zxt
public class UserDAOImpl extends BaseDAOHibernateImpl )+hV+rM jp
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implements UserDAO { msM1K1er
|PlNVd2
/* (non-Javadoc) Hddc-7s
* @see com.adt.dao.UserDAO#getUserByName ~y2zl
>a,D8M?
(java.lang.String) c%J6!\
*/ JD~;.3$/k
publicList getUserByName(String name)throws ,_fz)@)
"GZieI
D
HibernateException { !~Uj 'w
String querySentence = "FROM user in class AoeRoqg
*Ud(HMTe
com.adt.po.User WHERE user.name=:name"; \7uM5 k}l
Query query = getSession().createQuery lU%}_!tp3/
L]|mWyzT
(querySentence); 7P7OTN
query.setParameter("name", name); Pps-,*m
return query.list(); {@^;Nw%J
} B+j]C$8}
Z(T{K\)uN
/* (non-Javadoc) RHg-Cg`
* @see com.adt.dao.UserDAO#getUserCount() . \"k49M`
*/ `(sb
publicint getUserCount()throws HibernateException { R<Lf>p>_
int count = 0; ~DI$O[KpR%
String querySentence = "SELECT count(*) FROM UnF8#~
$+!dP{
user in class com.adt.po.User"; 1!~cPD'F
Query query = getSession().createQuery Y~-y\l;Tr
6t6Z&0$h~
(querySentence); |4Q*4s
count = ((Integer)query.iterate().next C/Khp +
)ODF6Ag
()).intValue(); ]~KLdgru_
return count; _XV%}Xb'
} GWnIy6TH l
jdP)y]c
/* (non-Javadoc) LdV&G/G-#D
* @see com.adt.dao.UserDAO#getUserByPage t>I.1AS
iqQT ^
(org.flyware.util.page.Page) 8w&-O~M
*/ UJ)pae
publicList getUserByPage(Page page)throws 2gPqB*H
d]pb1ECuu
HibernateException { '7-Yo
Q
String querySentence = "FROM user in class %w*)7@,+-
fkBL`[v)4
com.adt.po.User"; hMDd*<%l
Query query = getSession().createQuery 4^tSg#!V{
w +t@G`d
(querySentence); hfaU-IPcFX
query.setFirstResult(page.getBeginIndex()) )U?_&LY)[M
.setMaxResults(page.getEveryPage()); '4[=*!hs!
return query.list(); \^c4v\s<o#
} wZiUzS;v
:$MOdL[ir
} I6W`yh`I)
z1PwupXt1
O?JJE8~']
NXU:b"G
S
V&M*,#(?
至此,一个完整的分页程序完成。前台的只需要调用 }}JMwT
=?<WCR
C*
userManager.listUser(page)即可得到一个Page对象和结果集对象 `Vb
]:<!(
的综合体,而传入的参数page对象则可以由前台传入,如果用 `6D?te
dAh.I3
webwork,甚至可以直接在配置文件中指定。 cz>,sz~i
z-5`6aE9<
下面给出一个webwork调用示例: %lF*g
java代码: H5=kDkb
5Q?Jm~H9
$KiCs]I+
/*Created on 2005-6-17*/ Oj5UG*
package com.adt.action.user; &O&HczO
0
&zp
import java.util.List; Ts5)r(
\G" S7
import org.apache.commons.logging.Log; &S,D;uhF
import org.apache.commons.logging.LogFactory; =ejj@c
import org.flyware.util.page.Page; 8M,*w6P
A`c%p7Z%
import com.adt.bo.Result; Ps!MpdcL3
import com.adt.service.UserService; ;c(a)_1
import com.opensymphony.xwork.Action; |*&l?S
{PHH1dC{
/** "|SMRc
* @author Joa :Ha/^cC/3
*/ ,N.8
publicclass ListUser implementsAction{ liKlc]oM
eUyF<j
privatestaticfinal Log logger = LogFactory.getLog Jl
Do_}
>
;,S||
(ListUser.class); -/yqiC-yx
%tCv-aX4
private UserService userService; RgJ@J/p"
Ys"wG B>
private Page page; /{i~CGc;"
_4ag-'5
privateList users; 6>>; fy2
Kc/1LeAik
/* rhJ&* 0M
* (non-Javadoc) e~o!Qm
* \Pg~j\;F]
* @see com.opensymphony.xwork.Action#execute() 3nq?Y8yac
*/ +)Z]<O
publicString execute()throwsException{ fE#(M +(<
Result result = userService.listUser(page); diq}\'f
page = result.getPage(); D'"
T'@
users = result.getContent(); BuJo W@)
return SUCCESS; NB-dlv1
} oxwbq=a6yV
@T'^V0!-q:
/** t un}rdb
* @return Returns the page. Ot=jwvw
*/ g 9_ zkGc7
public Page getPage(){ "s2_X+4oY
return page; OxlA)$.hpu
} ;FPx
]P4WfV
d
/** hnnB4]c
* @return Returns the users. 0Y.z
*/ U&!TA(Yr
publicList getUsers(){ j#NyNv(jE1
return users; @CMI$}!{V
} =~#mF<z5
kB7vc>@1
/** !NXjax\r
* @param page $%<{zWQm
* The page to set. ?|nl93m
*/ 7#V7D6j1
publicvoid setPage(Page page){ IpP%WW u
this.page = page; wwUI ;g
} *}?[tR5
j6
wFks
/** x.Sf B[SZ
* @param users i'>6Qo
* The users to set. zp:dArh0
*/ ^_7|b[Bt
publicvoid setUsers(List users){ oV|O`n
this.users = users; -t`kb*O3`
} ?w3RqF@}
=%Y1] F
/** Ox3=1M0
* @param userService k(gbUlCc
* The userService to set. K9!HW&?<|
*/ }LHYcNw^z
publicvoid setUserService(UserService userService){ ^&zCPUH
this.userService = userService; TOwd+]B
} &?<uR)tl
} X Xque-
dkQ4D2W*\
TCr4-"`r-{
^Hd[+vAvR
]a $6QS
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, HiCh:IP7>/
EX8JlA\-W
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 %I1@{>OxG
_^NX`<&
么只需要: > p`,
java代码: mH o#"tc
,7{|90'V<
C{exvLQ
<?xml version="1.0"?> S?J!.(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 0w?da~
M4^G3c<
1.0//EN" "http://www.opensymphony.com/xwork/xwork- q<3nAE$?=
CM6% g f3
1.0.dtd"> 144Y.
Q!X?P
<xwork> OO:S2-]Y>e
uLhGp@Dx
<package name="user" extends="webwork- Od1\$\4Z
q_M N
interceptors"> \PrJy6&
iw@rW5%'~
<!-- The default interceptor stack name L9b.D<
A8{jEJ=)P
--> ZmA}i`
<default-interceptor-ref 7?P'f3)fG
dwO fEYC
name="myDefaultWebStack"/> uD\R3cY
f:o.[4p2
<action name="listUser" ~_ THvx1
M2$/x`\-~
class="com.adt.action.user.ListUser"> u$ts>Q;5
<param aLk3Yg@X
b<h((]Q>^
name="page.everyPage">10</param> 4:/]Y=)x
<result V!}I$JiJ
Y}~sTuWU
name="success">/user/user_list.jsp</result> >xWS>
</action> -@v^. @[Z&
iZGbNN
</package> Lg:1zC
Wu>]R'C
</xwork> eG=d)`.JaV
P,v7twc0M
5Xq+lLW>
xIdb9hm<
E=NjWO
Gu;40)gm
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 U/>I! 7oe
7HkO:/
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。 TWP@\ BQ
&RR;'wLoQT
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 WQ|Ufl;
$^x=i;>aK.
Fh~9(Y#
*5'8jC"2g
"4b{YWv
我写的一个用于分页的类,用了泛型了,hoho o&JoeKXor
,!=
sGUQ)
java代码: <ZC.9
Kz'GAm\
oj 8r*
package com.intokr.util; YwVA].p@TI
Xo PJ?63
import java.util.List; vo/x`F'ib
-rDfDdT
/** g=:o 'W$@
* 用于分页的类<br> #2=l\y-#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~WrpJjI[
* ZflB<cI
* @version 0.01 s_^`t+5
* @author cheng |d0X1(
*/ =dXHQU&Q
public class Paginator<E> { }Qo]~/
privateint count = 0; // 总记录数 b9g2mWL\T
privateint p = 1; // 页编号 *|&Y ,H?
privateint num = 20; // 每页的记录数 g *5_m(H
privateList<E> results = null; // 结果 2dts}G
u#6s^
)W
/** [s}W47N1
* 结果总数 wgz]R
*/ *q}yfa35eR
publicint getCount(){ 'o='Q)Dk
return count; E:`_P+2p
} GMU!GSY
P@y)K!{Nk
publicvoid setCount(int count){ l;M,=ctB(
this.count = count; Zma;An6
} C(>!?-.
r] /Ej!|
/** f2.=1)u.
* 本结果所在的页码,从1开始 2Z; !N37U
* XX=OyDLqP
* @return Returns the pageNo. 9Og
*/ :7{GOx
publicint getP(){ |5>Tf6$(
return p; g?
vz\_
} 2j
f!o
;CO qu#(
/** F=\
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* if(p<=0) p=1 8UB2 du@?
* 'IU3Xu[-.
* @param p G}U <^]c
*/ uQG|r)
publicvoid setP(int p){ EH".ki=e
if(p <= 0) S @[]znH
p = 1; %
J\G[dl
this.p = p; W@!qp
} UVDMYA0
+ 149 o2
/** 7\@c1e*e
* 每页记录数量 IlJ"t`Z9)
*/ :1d;jx>
publicint getNum(){ <gPM/4$G
return num; k7uX!}
} ~,,r\Y+
c{^1`(#?
/** =t N}4
* if(num<1) num=1 {?Slo5X|
*/ -axKnfj
publicvoid setNum(int num){ CUDA<Fm
if(num < 1) 4{>r_^8
num = 1; A}"|_&E
this.num = num; we}xGb.u
} v:lkvMq|=
",apO
/** 0}GO$%l
* 获得总页数 7<LuL
*/ YM#'+wl}`
publicint getPageNum(){ "s@Hg1
return(count - 1) / num + 1; "=2\kZ
} 'qV lq5.
G/
si( LK
/** p*K #s1
* 获得本页的开始编号,为 (p-1)*num+1 +wG
*qI
*/ y/@Bhzc
publicint getStart(){ !I|_vJ@<
return(p - 1) * num + 1; 5]mH.{$x$?
} .BjWZj
B<~AUf*y
/** wmpQF<
* @return Returns the results. qKSR5 #
*/ ,3rsjoKhd
publicList<E> getResults(){ #@nPB.
return results; !" FEp
} H/t0#
#0)TS
public void setResults(List<E> results){ 6l,6k~Z9
this.results = results; O0y0'P-rJq
} 75>%!mhM
ju:}%'
public String toString(){
/1TK+E$
StringBuilder buff = new StringBuilder Dj= {%
:xg
J2
(); |`yU \
buff.append("{"); DK2Wjr;
buff.append("count:").append(count); .|"E:qTD
buff.append(",p:").append(p); ,&Zp^
buff.append(",nump:").append(num); =ZSYg K
buff.append(",results:").append .NWsr*Tel
`]]m$
(results); T6SYXQd>.
buff.append("}"); uf]wX(*<k
return buff.toString(); PL"=>
} bv41et+Kb
;+DMv5A "
} u;%~P 9O
0rX%z$D+@
nVlZ_72d