Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 46$5f?Z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pRYt.}/K
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 aFl(K\
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 2P]r J
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分页支持类: -lLq)
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java代码: 1s1$J2LX
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package com.javaeye.common.util; *!B,|]wq=
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import java.util.List; GV%ibqOpQj
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publicclass PaginationSupport { ^#_@Kq%th
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publicfinalstaticint PAGESIZE = 30; 38JvJR yK}
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privateint pageSize = PAGESIZE; HPu nNsA
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privateList items; h( Iti&
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privateint totalCount; gl HHr
HQ4o^ WC
privateint[] indexes = newint[0]; Wny{qj)=
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privateint startIndex = 0; ?n[+0a:8E
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public PaginationSupport(List items, int %/~Sq?f-9@
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totalCount){ ;B!&( 50e
setPageSize(PAGESIZE); [{'` |
setTotalCount(totalCount); <sn^>5Ds
setItems(items); y/
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setStartIndex(0); hoPCbjkov
} 2}hEBw68
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public PaginationSupport(List items, int .hn"NXy
[9*+s
totalCount, int startIndex){ @_0XK)pW
setPageSize(PAGESIZE); (i&:=Bfn)
setTotalCount(totalCount); Lw2EA 5
setItems(items); dTS7l02
setStartIndex(startIndex); CSIW|R@
} 1[mX_ }K
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public PaginationSupport(List items, int T+Du/ERL
*<]ulR2
totalCount, int pageSize, int startIndex){ Fb.wm
setPageSize(pageSize); UG 9uNgzQ/
setTotalCount(totalCount); %nT!u!#
setItems(items); 0<nk>o
setStartIndex(startIndex); iCa#OQ
} jIg]?4bW[
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publicList getItems(){ T[q2quXgk
return items;
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} 08cCrG
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publicvoid setItems(List items){ r
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this.items = items; 8)/d8@
} ;MR8E9
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publicint getPageSize(){ [Vc8j&:L
return pageSize; 1Sx2c
} 42~tdD
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publicvoid setPageSize(int pageSize){ ~"#qG6dP
this.pageSize = pageSize; ?7*.S Lt
} Qw}uB$S>
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publicint getTotalCount(){ 4ba[*R2
return totalCount; ,F!zZNW9
} Z<@0~t_:?p
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publicvoid setTotalCount(int totalCount){ #;z;8q
if(totalCount > 0){ ACc tyGd
this.totalCount = totalCount; eD4X:^@
int count = totalCount / ?^n),mR
T1_O~<
pageSize; Kejp7okb
if(totalCount % pageSize > 0) wQEsq<
count++; d)1 d0ES
indexes = newint[count]; SFv'qDA
for(int i = 0; i < count; i++){ g1Ed:V]_
indexes = pageSize * |6v
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i; ~}pc&jz>q
} _Dr9 w&;<
}else{ 8BE] A_X
this.totalCount = 0; %|AebxB'o
} jmPnUn
} |Bz1u|uc
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publicint[] getIndexes(){ xy))}c%
return indexes; >J*x` a3Q
} ct`j7[
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publicvoid setIndexes(int[] indexes){ #9zpJ\E
this.indexes = indexes; Swa0TiT(
} Ql"kJ_F!br
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publicint getStartIndex(){ 0Q?)?8_
return startIndex; FkE)~g
} p>_Qns7W
& 6'Rc#\P
publicvoid setStartIndex(int startIndex){ sPX&XqWx
if(totalCount <= 0) ,.9k)\/V
this.startIndex = 0; BX\/Am11
elseif(startIndex >= totalCount) ~I6N6T Z
this.startIndex = indexes txE=AOY5
aKjP{Z0k$
[indexes.length - 1]; ~jC+6v
elseif(startIndex < 0) =' uePM")
this.startIndex = 0; 7-:R{&3Lm:
else{ l^F ?^kP
this.startIndex = indexes dq,j?~ _}
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[startIndex / pageSize]; v%:VV*MxF
} V'hb 4}@
} $vrkxn
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publicint getNextIndex(){ wXjidOd$
int nextIndex = getStartIndex() + \?Sv O
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pageSize; is
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if(nextIndex >= totalCount) ]Hp>~Zvbb
return getStartIndex(); XeX\u3<D
else n{u\t+f
return nextIndex; &AN1xcx\
} B (Ps/
cbN;Kv?ak}
publicint getPreviousIndex(){ m g,1*B'
int previousIndex = getStartIndex() - ^/_Yk.w
/~MH]Gh
pageSize; o^XDG^35`
if(previousIndex < 0) U%q-#^A
return0; F+"_]
else }}"pQ!Z
return previousIndex; GLgf%A`5/_
} G4uG"
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} 5r`rstV
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抽象业务类 6<2H 7'
java代码: 9 w$m\nV
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/** ~:{05W
* Created on 2005-7-12 M@#T`aS
*/ 9.8%Iw
package com.javaeye.common.business; vfc:ok 1
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import java.io.Serializable; -8xf}v~u
import java.util.List; |GtvgvO,
y{S8?$dU$:
import org.hibernate.Criteria; d2V X\
import org.hibernate.HibernateException; V\o7KF
import org.hibernate.Session; V:$+$"|
import org.hibernate.criterion.DetachedCriteria; RN[I%^$"
import org.hibernate.criterion.Projections; SRwD`FF
import #8|LPfA
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org.springframework.orm.hibernate3.HibernateCallback; tLBtE!J$[
import =A.$~9P
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org.springframework.orm.hibernate3.support.HibernateDaoS #0>xa]S
4);_f
upport; %8,$ILN
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import com.javaeye.common.util.PaginationSupport; T9C_=0(hn
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public abstract class AbstractManager extends CmZayV
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HibernateDaoSupport { +{1.kb
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privateboolean cacheQueries = false; .E<nQWz8
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privateString queryCacheRegion; J0?kEr
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publicvoid setCacheQueries(boolean ovdJ[bO
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cacheQueries){ Y3Fj3NwS
this.cacheQueries = cacheQueries; }5-w,m{8/
} nN\H'{Wzd
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publicvoid setQueryCacheRegion(String X` zWw_i
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queryCacheRegion){ unLhI0XW
this.queryCacheRegion = TIWR[r1!
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queryCacheRegion; G3~`]qf
} [ QiG0D_'=
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publicvoid save(finalObject entity){ f#\YX
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getHibernateTemplate().save(entity); wT4@X[5$
} $-iEcxsi
}d<R
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publicvoid persist(finalObject entity){ 7uF|Z(
getHibernateTemplate().save(entity); 7;s#QqG`I
} Y()"2CCV
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publicvoid update(finalObject entity){ p+CUYo(
getHibernateTemplate().update(entity); iRzFA!wH
} <s9?9^!!V^
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publicvoid delete(finalObject entity){ k, HC"?K
getHibernateTemplate().delete(entity); X2z<cJG|d@
} U ? +_\
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publicObject load(finalClass entity, 9;E=w+
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finalSerializable id){ uM-,}7f7
return getHibernateTemplate().load XBQt:7[<
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(entity, id); (N7uaZ?Z
} V!W.P
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publicObject get(finalClass entity, |'Fe?~P`
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finalSerializable id){ 558P"w0"X
return getHibernateTemplate().get 9a}9cMJ^"
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(entity, id); c0qp-=^&.
} fpD$%.y'J
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publicList findAll(finalClass entity){ Zw.8B0W
return getHibernateTemplate().find("from 7>FXsUt_
=<HDek
" + entity.getName()); Ld4U
} UB/> Ro
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publicList findByNamedQuery(finalString 1(
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namedQuery){ J ^'El^F
return getHibernateTemplate Zxa.x?:?n
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().findByNamedQuery(namedQuery); [#PE'i4
}
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publicList findByNamedQuery(finalString query, U2q6^z4l
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finalObject parameter){ {>]\<
return getHibernateTemplate p3I"LY
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().findByNamedQuery(query, parameter); +yGQt3U
} ,T$ts
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publicList findByNamedQuery(finalString query, 1Kg0y71"
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finalObject[] parameters){ d1b]+A G4
return getHibernateTemplate L, JQ\!c
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().findByNamedQuery(query, parameters); |>.Q U3
} Cp8=8N(Xb
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publicList find(finalString query){ RB 5SK#z
return getHibernateTemplate().find
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(query); $Ome]+0
} 2jsbg{QS#_
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publicList find(finalString query, finalObject dbI>\khI
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parameter){ YH&=cI@
return getHibernateTemplate().find JJ?{V:
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(query, parameter); 8bIP"!=*W
} /%wS5IZ^
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public PaginationSupport findPageByCriteria g3R(,IH
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(final DetachedCriteria detachedCriteria){ \br!77
return findPageByCriteria Q;h.}N8W
D /eH~
(detachedCriteria, PaginationSupport.PAGESIZE, 0); YOCEEh?
} "M I';6
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public PaginationSupport findPageByCriteria _(W@FS
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(final DetachedCriteria detachedCriteria, finalint ?jx]%n fV
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startIndex){ +mQ5\14#
return findPageByCriteria /d`"WK,
L@}PW)#
(detachedCriteria, PaginationSupport.PAGESIZE, dzVi ~wt_&
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startIndex); %@$UIO,(
} 4aW@c<-r?
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public PaginationSupport findPageByCriteria ]WT@&F
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(final DetachedCriteria detachedCriteria, finalint . [|UNg
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pageSize, iD^,O)b
finalint startIndex){ Jt~Ivn,
return(PaginationSupport) hI[}
-
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getHibernateTemplate().execute(new HibernateCallback(){ .@1+}0
publicObject doInHibernate
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(Session session)throws HibernateException { ,75)
Criteria criteria = *~rj!N?;
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detachedCriteria.getExecutableCriteria(session); "wUIsuG/p
int totalCount = pYr"3BwG
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((Integer) criteria.setProjection(Projections.rowCount tbrU>KCBD
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@
()).uniqueResult()).intValue(); o)`PSw=
criteria.setProjection }
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(null); Fs+tcr/\[
List items = O
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criteria.setFirstResult(startIndex).setMaxResults #-{<d%qk
U,P_bz*)
(pageSize).list(); k.J%rRneN
PaginationSupport ps = [4)Oi-_Y>
b3(*/KgK
new PaginationSupport(items, totalCount, pageSize, 9A.RD`fg
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startIndex); W!Tx%
return ps; m/HT3<F
} N?GTfN
}, true); <-lM9}vd
} STKL
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public List findAllByCriteria(final %?~'A59
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DetachedCriteria detachedCriteria){ }=R]<`Sj.j
return(List) getHibernateTemplate U(&c@u%
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().execute(new HibernateCallback(){ F^!D[:;jK
publicObject doInHibernate 3m1g"
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(Session session)throws HibernateException {
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Criteria criteria = V&Y`?Edc
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detachedCriteria.getExecutableCriteria(session); 8|&,JdT
return criteria.list(); -4Qub{Uym
} -V$|t<
}, true); jNZ.Fb
} )u?f| D
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public int getCountByCriteria(final l;8t%JV5
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DetachedCriteria detachedCriteria){ u6iW1,#
Integer count = (Integer) ULx:2jz
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getHibernateTemplate().execute(new HibernateCallback(){ #G9
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publicObject doInHibernate z/?* h
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(Session session)throws HibernateException { 7?lz$.*Avp
Criteria criteria = g)Z8WH$;H3
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detachedCriteria.getExecutableCriteria(session); w\C1Bh!
return 7UTfafOGX
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criteria.setProjection(Projections.rowCount )k<cd.MX
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()).uniqueResult(); H4M=&"ll}
} 4KPnV+h"b
}, true); (3e.q'
return count.intValue(); jaS<*_~#R
} ~DH9iB
} _|~Dj)z
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用户在web层构造查询条件detachedCriteria,和可选的 g{&5a(W&`
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {lK2yi
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PaginationSupport的实例ps。 ~[H8R|j "
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ps.getItems()得到已分页好的结果集 RO3LZBL
ps.getIndexes()得到分页索引的数组 iXWzIb}CJ-
ps.getTotalCount()得到总结果数 /gAT@Vx
ps.getStartIndex()当前分页索引 0E\#!L
ps.getNextIndex()下一页索引 Q#MB=:0{
ps.getPreviousIndex()上一页索引 {S0-y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Xg~9<BGsi
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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 08\w!!a:
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一下代码重构了。 %??v?M*
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我把原本我的做法也提供出来供大家讨论吧: 2:
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首先,为了实现分页查询,我封装了一个Page类: *+v*VH
java代码: I<}% L
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/*Created on 2005-4-14*/ xLed];2G
package org.flyware.util.page; %P}H3;2
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/** RUY7Y?
* @author Joa O=__w *<
* *VsGa<V
*/ ,X!) z Amm
publicclass Page { aiPm.h>
B}[CU='P*
/** imply if the page has previous page */ <M9NyD`
privateboolean hasPrePage; ?22U0UF
s AFn.W
/** imply if the page has next page */ :uo)-9_
privateboolean hasNextPage; =`x }9|[
4dixHpq'
/** the number of every page */ :]:)c8!6
privateint everyPage; iw#~xel<ez
{.Qv1oOa
/** the total page number */ 4T@+gy^.
privateint totalPage; a~Dk@>+P>
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/** the number of current page */ 0n:cmML)D
privateint currentPage; l%}q&_
bci]"uzB
/** the begin index of the records by the current <M\&zHv
he(K
query */ np2&W'C/i
privateint beginIndex; p2Khfl6-
*AV%=
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/** The default constructor */ +TbAtkEF*
public Page(){ )l9KDObis
Jqb~RP~
} NsI. mTc2
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/** construct the page by everyPage 7c"Csq/]I
* @param everyPage R'sNMWM
* */ .@): Uh
public Page(int everyPage){ Z,"4f*2
this.everyPage = everyPage; .Wt3|?\=nd
} U
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/** The whole constructor */ 'IY?=#xr'`
public Page(boolean hasPrePage, boolean hasNextPage, \ Bj{.jL
&]YyV .
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int everyPage, int totalPage, T1q27I
int currentPage, int beginIndex){ +D5gbxZX
this.hasPrePage = hasPrePage; -i?gYF!G
this.hasNextPage = hasNextPage; L ~'98C
this.everyPage = everyPage; w71YA#cg
this.totalPage = totalPage; tAq0Z)
this.currentPage = currentPage; T9R#.y,
this.beginIndex = beginIndex; .K84"Gdx
} lrZ]c:%k
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/** S?CT6moXA
* @return )!v"(i.5Xo
* Returns the beginIndex. \dJhDR
*/ |\dv$`_T
publicint getBeginIndex(){ -$"$r ~ad
return beginIndex; =Rx4ZqTI|
} O:#YLmbCN
rJGh3%
/** pl%!AY'oE>
* @param beginIndex <y8oYe_!
* The beginIndex to set. +YZo-tE
*/ sJKr%2nVV
publicvoid setBeginIndex(int beginIndex){ V?dwTc
this.beginIndex = beginIndex; M~\dvJ$cH
} ATqblU>D
O|sk"YXF
/** O)`L(
x
* @return :+6W%B
* Returns the currentPage. q83^?0WD
*/ ]=t}8H
publicint getCurrentPage(){ u
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return currentPage; UhqTn$=fb
} 27 XM&ZrZ
{[#)Q.2
/** nHm29{G0
* @param currentPage l6#Y}<tq
* The currentPage to set. _%R^8FjH*
*/ +r'&6Me!
publicvoid setCurrentPage(int currentPage){ W+;=8S
this.currentPage = currentPage; (=uT*Cb
} C*ep8{B
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/** mH\zSk
* @return i#>t<g`l
* Returns the everyPage. ^85Eveu
*/ Soq#cl'll-
publicint getEveryPage(){ <qfAW?tF
return everyPage; FWJ**J
} 4_5f4%S
HSysME1X:/
/** tkZUjQIX
* @param everyPage s8&q8r7%
* The everyPage to set. ~2\Sn-`
*/ 8<"g&+T
publicvoid setEveryPage(int everyPage){ [L2+k?
*
this.everyPage = everyPage; OGg\VV'
} F/ZFO5C%
|P]W#~Y-
/** }O7sP^
* @return P}~MO)*1
* Returns the hasNextPage. m6[}KkW
*/ ,V,mz?d^9
publicboolean getHasNextPage(){ ya1
aWs~
return hasNextPage; (9RfsV4^
} 7:olStK
,93Uji[l
/** LUD.
* @param hasNextPage qr4 lr!#t
* The hasNextPage to set. _|["}M"?
*/ ss%,
publicvoid setHasNextPage(boolean hasNextPage){ B?i#m^S
this.hasNextPage = hasNextPage; 'y;Kj
} _?H3*!>3
2, )>F"R
/** %\
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* @return ^O*-|ecA
* Returns the hasPrePage. tnobqL'
*/ *Z"`g
%,;
publicboolean getHasPrePage(){ &PE%tm
return hasPrePage; Lq5xp<
} 60^j<O
0#OyT'~V%
/** <~5O-.G]
* @param hasPrePage F:q4cfL6
* The hasPrePage to set. D%]S>g5k
*/ 'Z~ZSu
publicvoid setHasPrePage(boolean hasPrePage){ dvjj"F'Bf
this.hasPrePage = hasPrePage; UgAp9$=z
} 0]bt}rh
fY9+m}$S$
/** exJc[G&t(
* @return Returns the totalPage. ^%,{R},s
* YA$YT8iMe
*/ ,5v'hG
publicint getTotalPage(){ Q//
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return totalPage; *"WP*A\1
} |:5O|m '
h,R Isq;`
/** J-tqEK*
* @param totalPage Mu>
* The totalPage to set. iY/2 `R
*/ #4mRMsW5"
publicvoid setTotalPage(int totalPage){ nRc\!4
this.totalPage = totalPage; n5kGHL2
} \ji\r ]k
12U]=
} sMGo1pG(
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? Vd~
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Q&:)D7m\)S
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 rQ{|0+l
zA9q`ePS
个PageUtil,负责对Page对象进行构造: :|s;2Y
java代码: 5zBA ]1PY
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/*Created on 2005-4-14*/ Ck
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package org.flyware.util.page; Zq8 5q
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import org.apache.commons.logging.Log; -c&=3O!
import org.apache.commons.logging.LogFactory; `{!A1xKZ
;/$pxD
/** {.$7g8]I
* @author Joa mv99SOe[Fz
* g@^ y$wt
*/ U!q2bF<@
publicclass PageUtil { x
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@/kI;8
privatestaticfinal Log logger = LogFactory.getLog P^<3 Z)L
3%'`^<-V
(PageUtil.class); e2c'Wab
MS;^:t1`
/** d]e36Dwk
* Use the origin page to create a new page <8 <P,
* @param page KsOSPQDGE
* @param totalRecords Zzjx;SF
* @return ;)FvTm'"\.
*/ uSR%6=$
publicstatic Page createPage(Page page, int 8<;.
zK~8@{l}_"
totalRecords){ 3R<r[3WP
return createPage(page.getEveryPage(), w3,KqF
CmBPCjh
page.getCurrentPage(), totalRecords); ^$P_B-C N
} :G 5p`;hGo
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/** DGGySO6=$e
* the basic page utils not including exception 5go)D+6s
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handler 8(4!x$,Z5
* @param everyPage |iUF3s|?
* @param currentPage 9ia&/BT7"z
* @param totalRecords ra*|HcLD
* @return page 6<W^T9}v@/
*/ h>!h|Ma
publicstatic Page createPage(int everyPage, int :epBd3f
A x8 >
currentPage, int totalRecords){ NxnRQS
everyPage = getEveryPage(everyPage); tZ[9qms^_
currentPage = getCurrentPage(currentPage); d[l8qaD
int beginIndex = getBeginIndex(everyPage, B bmw[Qf\
_'cB<9P
currentPage); mH$ `)i8
int totalPage = getTotalPage(everyPage, h81giY]
xBxiBhqzF
totalRecords); L;:PeYPL
boolean hasNextPage = hasNextPage(currentPage, k?7"r4Vc)S
=Ya^PAj '}
totalPage); w&H>`l06
boolean hasPrePage = hasPrePage(currentPage); NE#`ZUr3
WVyDE1K<
returnnew Page(hasPrePage, hasNextPage, @lDnD%vZ`
everyPage, totalPage, n>u_>2Ikkj
currentPage, 9<rs3 84
]vf_4QW=
beginIndex); T4:H:
} MMrN#&r
@Pc7$ qD %
privatestaticint getEveryPage(int everyPage){ OiAuL:D
return everyPage == 0 ? 10 : everyPage; !q$VnqFk
} &w^9#L
vGsAM*vw6
privatestaticint getCurrentPage(int currentPage){ vh.8m$,
return currentPage == 0 ? 1 : currentPage; t"Du
} <UO[*_,\
^E/6vG
privatestaticint getBeginIndex(int everyPage, int OH>Gc-V
vUbgSI
currentPage){ -`5]%.E&8
return(currentPage - 1) * everyPage; xT&/xZLT
} A\S=>[ar-
p,z>:3M
privatestaticint getTotalPage(int everyPage, int uzQj+Po
VOj7Tz9UD
totalRecords){ \1<aBgKi
int totalPage = 0; <[ dt2)%L>
S}Wj.l+F
if(totalRecords % everyPage == 0) tOVTHx3E]
totalPage = totalRecords / everyPage; nL^7t7mp
else `%[m%Y9h
totalPage = totalRecords / everyPage + 1 ; c86?-u')
}f;TG:6
return totalPage; /Zs_G=\>
} &zgliT!If
TX YO{
privatestaticboolean hasPrePage(int currentPage){ z4D)Xy"/
return currentPage == 1 ? false : true; 'J*'{
} +(x(Ybl#
b'^<0c
privatestaticboolean hasNextPage(int currentPage, U= GJuixy
V(K;Gc
int totalPage){ umuj>
return currentPage == totalPage || totalPage == 9+*{3 t
Heqr1btK
0 ? false : true; PSAEW.L
} .I|b9$V
-}xK>
["
mW)kWuOO
} 3BK
8{/
x2fqfrr_]
"PTEt{qn
SD~4CtlfI
=@O&$&
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。 %Qj$@.*:
8[@Y`j8
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ~a
V5
zE8_3UC
做法如下: 3s]o~I 2x
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]srL>29_b
0ie)$fi
的信息,和一个结果集List: Vq#0MY)2gS
java代码: a"4X7
D+
21<Sfsc$
$[HCetaqV
/*Created on 2005-6-13*/ w$s6NBF7
package com.adt.bo; gZ>&cju
n=DmdQ}
import java.util.List; #(}{*dR
FDF DB
import org.flyware.util.page.Page; x/]G"?Uix
jEx8G3EL
/** ' p!&&.%
* @author Joa 4+>~Ui_#
*/ pIrL7Pb0
publicclass Result { Q+a&a]*KL^
7a_u=\,
private Page page; SsMs#C8u%
sw1gpkX
private List content; &)q>Z!C-l
^Hf?["m^@
/** D?xR>Oo)
* The default constructor ?Nt m5(R
*/ Su@V5yz
public Result(){ 8:I-?z;S
super();
StNA(+rT
} &!:mL],
u9q#L.Ij
/** U7zd7O
* The constructor using fields
`|nJAW3
* v8\_6}*I
* @param page E2o8'.~Yd`
* @param content oKkDG|IE
*/ wE9z@\z]
public Result(Page page, List content){ R'_F9\
this.page = page; m/g[9Y
this.content = content; mm!JNb9(
} NU.4_cixb
,{ 0&NX
/** o@$pyU8
* @return Returns the content. I+Qt5Ox
*/ aY,'^S
publicList getContent(){ @GweNo`p7
return content; R SWw4}
} YuO!Y9iEm
[ x.]
/** F`gK6;zp
* @return Returns the page. ER!s
*/ jX$U)O
public Page getPage(){ lUnC+w#[
return page; LChwHkRHJI
} =`MQKh,
|gk"~D
/** LDo~
* @param content Qdc#v\B
* The content to set. h|z59h&X8G
*/ qpf|.m
public void setContent(List content){ 5
r<cna
this.content = content; B.Z5+MgM
} 04X/(74
Wb^g{F!W
/** GVu-<R
* @param page d_V7w4lK
* The page to set. v~dUH0P<>e
*/ :Ef$[_S>
publicvoid setPage(Page page){ DoeE=X*`k
this.page = page; <c(%xh46
} 1X&scVw
} \Z/0i|
8"wavh|g4
Hnvs{KC`
o(i?_4E
@-1VN;N
2. 编写业务逻辑接口,并实现它(UserManager, #zn`)n
S6yLq|W0
UserManagerImpl)
6l|SGt\
java代码: Q^lgtb
M~saYJio
R|O^7o
/*Created on 2005-7-15*/ %yVP@M
package com.adt.service; VRv.H8^{
t<p4H^
import net.sf.hibernate.HibernateException; XPi5E"
NQbgk+&wD
import org.flyware.util.page.Page;
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EF6"PH+J@
import com.adt.bo.Result; mFC9\
srU*1jD)
/** :?3y)*J!
* @author Joa $4CsiZ6
*/ gln
X C
publicinterface UserManager { ^S(["6OJ(
.X4UDZQg
public Result listUser(Page page)throws y
0fI7:e3
nhq,Y0YH
HibernateException; eGrxS;NY
Xr|e%]!**
} h4>q~&Pd
Y-"7R>^I
7I@@}A
`v Ebm Xb
!xC IvKW
java代码: 9aKCO4
_ba.oIc
4':U rJ+
/*Created on 2005-7-15*/ EhIa31>X
package com.adt.service.impl; WWIQ6EJO
d[e;Fj!
import java.util.List; 7lQ:}&
&,=t2_n
import net.sf.hibernate.HibernateException; G"prq&
RjHKFB2
import org.flyware.util.page.Page; Z9I
?j1K|!
import org.flyware.util.page.PageUtil; .|J-(J<>[.
>D$NEO^
import com.adt.bo.Result; ozG!OiRW
import com.adt.dao.UserDAO; M|'![]-
import com.adt.exception.ObjectNotFoundException; ==W] 1@s
import com.adt.service.UserManager; [iG4qI
URxy*)
/** PKNpR
* @author Joa ddeH-Z
*/ >Q# !.lH$W
publicclass UserManagerImpl implements UserManager { hjoxx
F\_
gm@%[
private UserDAO userDAO; dO[pm0
nc>Ae`"(
/** 6[C>"s}Ol
* @param userDAO The userDAO to set. ]0@
J)Z09
*/ fK9wr@1
publicvoid setUserDAO(UserDAO userDAO){ X7 fJ+Cn
this.userDAO = userDAO; 2Rs-!G<]
} [-x]%
%VzCeS9
/* (non-Javadoc) JKYkS*.a}
* @see com.adt.service.UserManager#listUser F,$ypGr
|^kfa_d
(org.flyware.util.page.Page) mwqe@7
*/ ew6\Z$1c~
public Result listUser(Page page)throws .Vb\f
<<ifd?
HibernateException, ObjectNotFoundException { zE4TdT1y|
int totalRecords = userDAO.getUserCount(); ,~xX[uB
if(totalRecords == 0) 5Og=`T
throw new ObjectNotFoundException F$&{@hd
=5X(RGK
("userNotExist"); rXg#_c5j
page = PageUtil.createPage(page, totalRecords); f{u3RCfX~2
List users = userDAO.getUserByPage(page); y@Ga9bI7
returnnew Result(page, users); YumHECej
} yBxWBW*e
nQ^<h.
} 73d7'Fw
i_qR&X
R4g% $}
srfM"Lb'
3eS
*U`_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ZzV%+n7<Vx
sa>}wz<o
询,接下来编写UserDAO的代码: +zLh<q 0
3. UserDAO 和 UserDAOImpl: f^[:w1X$sM
java代码: q`DilZ]S
)'gO?cN
QO%#.s
/*Created on 2005-7-15*/ ~Uw<E:?v
package com.adt.dao; F~_)auH
vT>ki0P_;
import java.util.List; F`\7&'I
ZI'Mr:z4
import org.flyware.util.page.Page; A#B6]j)
Yhkn(k2
import net.sf.hibernate.HibernateException; ^l"
]@MBE1M
/** C 9:5c@G
* @author Joa e^ygQ<6%
*/ s9-aPcA
publicinterface UserDAO extends BaseDAO { ROB/#Td
4chSo.= 4V
publicList getUserByName(String name)throws KD5} Nk)t
(qM(~4|`
HibernateException; =W~K_jE5lo
w %sHA
publicint getUserCount()throws HibernateException; tag~SG`ov
/*8Ms`
publicList getUserByPage(Page page)throws ?3
l4U
tv1Z%Mx?Cp
HibernateException; =8F]cW'1`
SXx2
} 7VQk$im399
'cx&:s
g5*Zg_G/
M4 :}`p=
V=,VOw4
java代码: Gf{FFIe(
g^EkRBU
^KK6 d
/*Created on 2005-7-15*/ a:(.{z?nM
package com.adt.dao.impl; ~ST7@-D0
>b.wk3g@>
import java.util.List; 6mi:%)"
p kR+H|
import org.flyware.util.page.Page; C r~!N|(
,!RbFME&H
import net.sf.hibernate.HibernateException; Iq-+X3i
import net.sf.hibernate.Query; W 6m
oFn
<""
fJ`7
import com.adt.dao.UserDAO; D<2|&xaR
loLN
~6
/** L[Dr[
* @author Joa FM3DJ?\L-
*/ J c~{ E
public class UserDAOImpl extends BaseDAOHibernateImpl ? }2]G'7?
;*Cu >f7
implements UserDAO { 0{PRv./`
p/a)vN+*x'
/* (non-Javadoc) [o=v"s't)
* @see com.adt.dao.UserDAO#getUserByName ^sNj[%I
R
\666{. a
(java.lang.String) j<LDJi>O
*/ ~fE6g3
publicList getUserByName(String name)throws Zw[A1!T,
;{e ;6Hq
HibernateException { K)AJx"
String querySentence = "FROM user in class Q`dzn=
[CU]fU{$
com.adt.po.User WHERE user.name=:name"; #*[G,s#t^
Query query = getSession().createQuery :Q\{LB c
rN'')n/F
(querySentence); dX0"h5v1
query.setParameter("name", name); X=<-rFW
return query.list(); 1{sf Dw[s
} /OpVr15
4q`$nI Bi
/* (non-Javadoc) (\ze
T5
* @see com.adt.dao.UserDAO#getUserCount() B!=JRfT
*/ u*ZRU
4U
publicint getUserCount()throws HibernateException { fBptjt_
int count = 0; TqM(I[J7\
String querySentence = "SELECT count(*) FROM 8jE6zS}m
0~{&
user in class com.adt.po.User"; l0m\2Ttf
Query query = getSession().createQuery S1<m O-
lqO"
(querySentence); j7vp@l6`L
count = ((Integer)query.iterate().next L+}q !'8S
ptS1d$
()).intValue(); .cTK\
return count; l;I)$=={=
} 6O^'J~wiI
t$sL6|Ww}o
/* (non-Javadoc) Ri@`sc{n
* @see com.adt.dao.UserDAO#getUserByPage ZX0ZN2 ]
6]%79?'A
(org.flyware.util.page.Page) 0k?ph$
*/ QPf#y7_@u
publicList getUserByPage(Page page)throws W?a2P6mAh
K0#kW \4`
HibernateException { asDq(J`sQ
String querySentence = "FROM user in class 'Jb6CRn
0ivlKe%
com.adt.po.User"; qsjTo@A
Query query = getSession().createQuery ?qeBgkL(B^
g7*ii
X
(querySentence); l^s\^b=W
query.setFirstResult(page.getBeginIndex()) ,r{[l D^
.setMaxResults(page.getEveryPage()); ps#+i
return query.list(); }*{@-v|_R
} "#4p#dM0e
8KioL{h
} u.wm;eK[
GbC-6.~
&j\<UPn
=#@eDm%
SCClD6k=V
至此,一个完整的分页程序完成。前台的只需要调用 "5]Fl8c?
=_%i5]89P
userManager.listUser(page)即可得到一个Page对象和结果集对象 h 7feZ_
]&za^%q0&
的综合体,而传入的参数page对象则可以由前台传入,如果用 a
D*
nR7 usL
webwork,甚至可以直接在配置文件中指定。 78v4cQ Y
LFsrqdzJ
下面给出一个webwork调用示例: U!E
java代码: SMr
]Gf.
oyGO!j
3"O)"/"Q.
/*Created on 2005-6-17*/ CKShz]1
package com.adt.action.user; &u62@ug#}
y$VYWcFE
import java.util.List; +~O0e-d
mC
P*v-
import org.apache.commons.logging.Log; SbNs#
import org.apache.commons.logging.LogFactory; 6&o9mc\I
import org.flyware.util.page.Page; ?UC3ES
o2
=UUD&
import com.adt.bo.Result; 'iM;e K
import com.adt.service.UserService; L lmdydC%
import com.opensymphony.xwork.Action; D ];%Ey
,6,sz]3-
/** 3/P#2&jt
* @author Joa |wASeZMO2
*/ MB9tnGO-Q
publicclass ListUser implementsAction{ \atztC{-L>
re9*q
privatestaticfinal Log logger = LogFactory.getLog Q:I2\E
{shf\pm!o
(ListUser.class); D-8NDa(`
P"dWh;I_
private UserService userService; 5"4O_JQ
cd36f26`"w
private Page page; 0h~Iua5
R;9H`L/>
privateList users; hlPZTr=a
H6ff b)&
/* U$[C>~ r
* (non-Javadoc) v:*t5M
>
* $vNz^!zgV
* @see com.opensymphony.xwork.Action#execute() }cK<2J#
*/ .\kcWeC\
publicString execute()throwsException{
2BLcun
Result result = userService.listUser(page); h_K(8{1
page = result.getPage(); 49%qBO$R
users = result.getContent(); @SREyqC4
return SUCCESS; #hEN4c[Ex
} W+
tI(JZ
ze!S4&B
/** HC0q_%j
* @return Returns the page. aa8xo5tIp
*/ Y>KRI2](<
public Page getPage(){ ]C|Zs=5
return page; ng]jpdeA
} Z:VqBqK
R:zPU
/** 7XKPC+)1ya
* @return Returns the users. Vv=/{31
*/ S<"M5e
publicList getUsers(){ *I;,|Jj k
return users; 6Z~u2&
} !8q+W`{
)clSW
/** ;[%_sVIy
* @param page YfBb=rN2s
* The page to set. 0-H! \IB
*/ _3UH"9g{
publicvoid setPage(Page page){ %liu[6_
this.page = page; +Hz});ix<
} Mq-QWx"P
(lwrk(
/** <rUH\z5cP
* @param users QUL^]6$
* The users to set. 5'f4=J$Z)
*/ Z$R6'EUb1
publicvoid setUsers(List users){ /\L|F?+@
this.users = users; H=E`4E#k
} %Gp%l
Jz D
Mx?
/** W:q79u yX
* @param userService }Z
T{
* The userService to set. $:M *$r^u
*/ Jy)E!{#x
publicvoid setUserService(UserService userService){ wD|,G!8E2
this.userService = userService; ]>fAV(ix
} YUo{e=m|
} 7a_pO1MBL
|;2Y|>=
5urM,1SQ@
wjk-$p
sS 5 ]d8
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ugexkdgM
Xg:w;#r,
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 *<k8H5z8]
dR"H,$UH
么只需要: h&eu}aF
java代码: x\t)uM%
r\7F}ZW/
=[%ge{ ,t
<?xml version="1.0"?> &6fNPD(|
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _E eH
\u@4eBAV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~_WsjD0O
pEk^;
1.0.dtd"> ,Y&LlB 2
/(C?3}}L
<xwork> yidUtSv=,
FQdz":5
<package name="user" extends="webwork- 7%?2>t3~
7'wt/9
interceptors"> ~=h M y`Ml
)i8Hdtn
<!-- The default interceptor stack name ;AV[bjRE\
%bo0-lnp
--> N9LBji;nH
<default-interceptor-ref j-wSsjLk
*yJCnoF
name="myDefaultWebStack"/> oTOr,Mn0\6
&$yC+cf
<action name="listUser" n4Fh*d ixg
8A/;a{
class="com.adt.action.user.ListUser"> s%h|>l[lKT
<param 0r?975@A
Oo'IeXQ9(
name="page.everyPage">10</param> n%;wQ^
<result c$?(zt;
tins.D
name="success">/user/user_list.jsp</result> :V1ttRW}52
</action> eliT<sw8
]v=*WK
</package> |J:n'}
Q 6djfEN>
</xwork> OiI[w8
#<ppiu$
*Ag</g@ h
AR9D;YfR~
j)4:*R.Z]
+_Nr a
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 =zw=Jp
~jdvxoX-
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。 shjc`Tqm
[fF0Qa-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $hexJzX
~B!O
X
; MU8@?yN
C[f'1O7
Xup rl2+
我写的一个用于分页的类,用了泛型了,hoho R=uzm=&nR
$4K(AEt[
java代码: ~WH4D+
Oax*3TD
#+)AIf
package com.intokr.util; I&9_F%rX
6&8 ([J
import java.util.List; yuyI)ebC
GE;S5X]X
/** hV5Aw;7C
* 用于分页的类<br> O
<;Au|>*
* 可以用于传递查询的结果也可以用于传送查询的参数<br> kTQ.7mo/\'
* \Eq,4-q
* @version 0.01 up+W[#+
* @author cheng v+a$Xh3Y~
*/ u{#}Lo>B #
public class Paginator<E> { G-`4TQ
privateint count = 0; // 总记录数 X}T/6zk
privateint p = 1; // 页编号 0k]$ he;h
privateint num = 20; // 每页的记录数 `Y HnL4
privateList<E> results = null; // 结果 /Y=Cg%+
f4A;v|5_
/** =l6aSr
* 结果总数 DONXq]f:,"
*/ ~)!yl. H
publicint getCount(){ ~)5NX
4Po
return count; y
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} O@*7O~eO
V_b"^911r
publicvoid setCount(int count){ a=(D`lQ8
this.count = count; @qP
uYFnw
} N?cvQR{r9
q18IqY*Lo
/** W?y7mw_S
* 本结果所在的页码,从1开始 wOW#A}m'vj
* `SDpOqfIrP
* @return Returns the pageNo. "R8: s
*/ Ul"9zTH
publicint getP(){ 50,`=Z
return p; iuxI$
} l%vX$Kw
;bz|)[4/
/** "Zk# bQ2j
* if(p<=0) p=1 <sU?q<MC
* WiDl[l"{9
* @param p ?`9XFE~a!
*/ Y"Y%JJ.J
publicvoid setP(int p){ W 7xh
if(p <= 0) zNAID-5K;
p = 1; @VdkmqXz
this.p = p; NifD
pqjgt
} jA<(#lm;
EPEy60Rx5
/** Fjnp0:p9X
* 每页记录数量 Q]44A+M]
*/ 'G] P09`*)
publicint getNum(){ NC]]`O2r@
return num; 2o8:[3C5
} >"LHr&;m&h
^HS;\8Xvb
/** 0tA~Y26
* if(num<1) num=1 ?vA)F)MS
*/ .h({ P#QT
publicvoid setNum(int num){ Uc>kiWW
if(num < 1) x9l l 0Ht
num = 1; k2bjBAT
this.num = num; KGM9
b
} Y.}"<{RQ
rV{:'"=y-
/** IP?15l w
* 获得总页数 =sm<B^yj
*/ @`Fv}RY{
publicint getPageNum(){ |uUGvIsXn
return(count - 1) / num + 1; RIC\f_Dv
} [j3-a4Wu
`efC4#*!!
/** I |PEC-(
* 获得本页的开始编号,为 (p-1)*num+1 3o_)x
*/ {^J/S}L]
publicint getStart(){ bEQy5AX
return(p - 1) * num + 1; G3.*fSY$.<
} z6IOVQ*r
$ol]G`+
/** K20,aWBq;3
* @return Returns the results. rCK
*/ /EIQMZuYp
publicList<E> getResults(){ 0Cg}yy Oz
return results; |~K 5]
} hQeGr2gMq
|mM K9OEu
public void setResults(List<E> results){
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".v+
this.results = results; 'c&[ kMR
} FmtgH1u:=
DX2_}|$!
public String toString(){ AX%N:)_$|
StringBuilder buff = new StringBuilder .B+Bl/
"L0Q"t:
(); Z bW!c1s{
buff.append("{"); 7"_m?c8
buff.append("count:").append(count); z|F38(%JJN
buff.append(",p:").append(p); 0&~JC>S
buff.append(",nump:").append(num); exZgk2[0
buff.append(",results:").append %jE0Z4\
uIy$|N
(results); [+F6C
buff.append("}"); I!?)}d
return buff.toString(); @*16agGg
} b FMBIA|
l\/uXP?
} 1gA^Qv~?
bhl9:`s
.rwa=IW