Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #)VF3T@#'
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 M"To&?OI
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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 /_ajaz%
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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 Uoix
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分页支持类: YZJyk:H\
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java代码: wwcBsJ1{
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package com.javaeye.common.util; S$XSei_q
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import java.util.List; kg\>k2h
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publicclass PaginationSupport { 6D_D' ;o
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publicfinalstaticint PAGESIZE = 30; UkGCyGyZ[
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privateint pageSize = PAGESIZE; w@fi{H(R
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privateList items; Jj%K=sw
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privateint totalCount; Yu2Bkq+
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privateint[] indexes = newint[0]; jZrq{Z<
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privateint startIndex = 0; &PtJ$0%q
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public PaginationSupport(List items, int IMONgFBS
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totalCount){ y1L,0 ]
setPageSize(PAGESIZE); +m,yA mEEd
setTotalCount(totalCount); 2^yU ~`#
setItems(items); iO;
7t@]-
setStartIndex(0); ,~W|]/b<q
} FJ?IUy 6
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public PaginationSupport(List items, int Dv`c<+q(#
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totalCount, int startIndex){ e\75:oQ
setPageSize(PAGESIZE);
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setTotalCount(totalCount); RViuJ;
setItems(items); }*"p?L^p{
setStartIndex(startIndex); Kx JqbLUC
} IIx#2r
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public PaginationSupport(List items, int 7. ;3e@s
` sU/& P
totalCount, int pageSize, int startIndex){ ,$&&-p I]
setPageSize(pageSize); @Do= k
setTotalCount(totalCount); ;sFF+^~L
setItems(items); VVOd]2{
setStartIndex(startIndex); 3sZ\0P}
} ,s;UfF
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publicList getItems(){ G,w(d@
return items; 3=ymm^
} VY\&8n}e(
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publicvoid setItems(List items){ <Q?F?.^e
this.items = items; UFuX@Lu0
} $iz|\m
4+ Z]3oIRE
publicint getPageSize(){ 5/Uy{Xt
return pageSize; {Y9q[D'g .
} '2^Q1{ :\
6)Lk-D
publicvoid setPageSize(int pageSize){ i
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this.pageSize = pageSize; Pgea NK5Y
} cYt!n5w~W
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publicint getTotalCount(){ 4HA<P6L
return totalCount; A3@6N(
} cExS7~*
*;*r8[U}q
publicvoid setTotalCount(int totalCount){ rw
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if(totalCount > 0){ um0N)&iY
this.totalCount = totalCount; P";'jVcR
int count = totalCount / 0lR5<^B
s->^=dy
pageSize; MFk5K
if(totalCount % pageSize > 0) "9e\c;a
count++; L;I]OC^J
indexes = newint[count]; sLQ^F
for(int i = 0; i < count; i++){ DR<9#RRD
indexes = pageSize * G'A R`"F
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i; 7Jho}5J
} ~Jz6O U*z
}else{ ixD)VcD-f
this.totalCount = 0; CzEd8jeh7
} sLAQE64\"
} _a T5jR=
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publicint[] getIndexes(){ )+ 2hl
return indexes; LSr]S79N1
} ~R92cH>L
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publicvoid setIndexes(int[] indexes){ e**qF=HCw
this.indexes = indexes; [HZv8HU|
} 6,{$J
Q$Q([Au
publicint getStartIndex(){ ,DkNLE
return startIndex; 6 ~w@PRy
} N//KPh
<GaS36ZW
publicvoid setStartIndex(int startIndex){ *bA.zmzM
if(totalCount <= 0) "1M[5\Ax
this.startIndex = 0; B_m8{44zM
elseif(startIndex >= totalCount) >I&5j/&}+
this.startIndex = indexes 6j LCU%^
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[indexes.length - 1]; hZ
elseif(startIndex < 0) ;MdlwQ$`
this.startIndex = 0; dNeVo|Y~h
else{ WEi2=3dV
this.startIndex = indexes @2 fg~2M1
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[startIndex / pageSize]; :X
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} G*P#]eO
} ^3L0w}#
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publicint getNextIndex(){ |_@>*Vmg
int nextIndex = getStartIndex() + ,1o FPa{?
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pageSize; VS8Rx.?
if(nextIndex >= totalCount) b}TS0+TF
return getStartIndex(); JrRH\+4K
else j HJ`,#
return nextIndex; u5f9Jw}
} j\^CV?}sm'
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publicint getPreviousIndex(){ y/ef>ZZ
int previousIndex = getStartIndex() - Gu\q%'I
@QP z#-
pageSize; M:B=\&.O
if(previousIndex < 0) 338k?nHxv
return0; U#WF;q0L
else p4
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return previousIndex; '@k+4y9q?
} L>4"(
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} mSh[}%swj
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抽象业务类 mSl.mi(JiZ
java代码: K^<BW(s
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/** 0[?Xxk}s0
* Created on 2005-7-12 ?QdWrE_
*/ p]2128kqx
package com.javaeye.common.business; >V8-i`
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import java.io.Serializable; LIF7/$,0
import java.util.List; )W
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import org.hibernate.Criteria; _H7x9
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import org.hibernate.HibernateException; EaY?aAuS:
import org.hibernate.Session; }Sh?S]]`
import org.hibernate.criterion.DetachedCriteria; l L@XM2"
import org.hibernate.criterion.Projections; eF-."1
import B!L{
1JG'%8}#8
org.springframework.orm.hibernate3.HibernateCallback; C{xaENp
import ywmo#qYe
h_,i&d@(
org.springframework.orm.hibernate3.support.HibernateDaoS ShP^A"Do
ag;pN*z
upport; ~[nSXnPO
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import com.javaeye.common.util.PaginationSupport; Ad9}9!<
h_3E)jc
public abstract class AbstractManager extends ! Y~FLA_
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HibernateDaoSupport { By",rD- r
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privateboolean cacheQueries = false; k1Y ?
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privateString queryCacheRegion; dhf!o0'1M
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publicvoid setCacheQueries(boolean Vl=l?A8
d_E/8R_$L
cacheQueries){ i0kak`x0
this.cacheQueries = cacheQueries; ;LPfXpR
} 4ber!rJM
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publicvoid setQueryCacheRegion(String yT"Eq"7/Y#
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queryCacheRegion){ l<LP&
this.queryCacheRegion = H.|#c^I
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queryCacheRegion; K6/Q}W
} F Q7T'G![
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publicvoid save(finalObject entity){ tGh~!|P
getHibernateTemplate().save(entity); kYqU9cB~
} HU8900k+
;!mzyb*
publicvoid persist(finalObject entity){ ^Y>F|;M#
getHibernateTemplate().save(entity); "fCu=@i
} gx8ouOh
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publicvoid update(finalObject entity){ ,c$_t+
getHibernateTemplate().update(entity); V6&!9b
} 0w\zLU
:uq\+(9
publicvoid delete(finalObject entity){ QQ*hCyw!
getHibernateTemplate().delete(entity); D9CaFu
} p$NQyS5C"S
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publicObject load(finalClass entity, J!v3i*j\
6Z6'}BDP
finalSerializable id){ @uqd.Q
return getHibernateTemplate().load j9x<Y]
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(entity, id); MSQEO4ge
} uy[At+%zg
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publicObject get(finalClass entity, w(*vj
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finalSerializable id){ (lBCO?`fx
return getHibernateTemplate().get (>UZ<2GPL
2\A$6N;_
(entity, id); UUYSFa%
} g|DF[
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publicList findAll(finalClass entity){ c?f4Q,%|
return getHibernateTemplate().find("from f}#~-.NGs
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" + entity.getName()); $Uq|w[LA
} G6q
}o)[m)
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publicList findByNamedQuery(finalString n71r_S*
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namedQuery){ ?K$(817
return getHibernateTemplate oo/qb`-6
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().findByNamedQuery(namedQuery); =1FRFZI!j
} v}}F,c(f
:}L[sl\R
publicList findByNamedQuery(finalString query, 'Vzp2
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finalObject parameter){ [i21FX
return getHibernateTemplate xBThq?N?
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().findByNamedQuery(query, parameter); 9|^2",V
} {k>&?Vd!
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publicList findByNamedQuery(finalString query, q~b&
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finalObject[] parameters){ |sJ[0z
return getHibernateTemplate #px+;k5
VZp5)-!\
().findByNamedQuery(query, parameters); !_]Y~[
} O@T9x$
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publicList find(finalString query){ [`#CXq'
return getHibernateTemplate().find @wGPqg
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(query); e/KDw
} !fV+z%:
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publicList find(finalString query, finalObject #5Q pu
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parameter){ vONasD9At
return getHibernateTemplate().find p,EQ#Ik
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(query, parameter); jnkR}wAA
} L4@K~8j7
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public PaginationSupport findPageByCriteria =m]v8`g
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(final DetachedCriteria detachedCriteria){ -V*R\,>
return findPageByCriteria .Yamc#A-
m<<+
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]g#: KAqz
} \0^Kram>
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public PaginationSupport findPageByCriteria v^sv<4*%
paA(C|%{
(final DetachedCriteria detachedCriteria, finalint AwCcK6N1
6iry6wcHm
startIndex){ Hc;[Cs0
return findPageByCriteria f$o_e90mu
vz@A;t
(detachedCriteria, PaginationSupport.PAGESIZE, w49t9~
Fx] WCQo
startIndex); #>a\>iKQ2q
} S^JbyD_yoh
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public PaginationSupport findPageByCriteria pE3?"YO
vSGH[nyCY
(final DetachedCriteria detachedCriteria, finalint ^)470K`%)
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pageSize, 7zl5yKN
finalint startIndex){ ]
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return(PaginationSupport) v8w q,CYV
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getHibernateTemplate().execute(new HibernateCallback(){ mtpeRVcF
publicObject doInHibernate H-!,yte
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(Session session)throws HibernateException { dUD[e,?
Criteria criteria = WSPI|#Xr%
8$]1M,$r
detachedCriteria.getExecutableCriteria(session); :^<3>zk
int totalCount = Q8$}@iA[
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((Integer) criteria.setProjection(Projections.rowCount XMCXQs&
SjK
()).uniqueResult()).intValue(); <q)#
criteria.setProjection K$z2YJ%
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(null); j\ZXG=j
List items =
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tb 5`cube
criteria.setFirstResult(startIndex).setMaxResults kx8G
`](e:be}
(pageSize).list(); NYhB'C2
PaginationSupport ps = RV1coC.g4x
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new PaginationSupport(items, totalCount, pageSize, Mg+2.
8%
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startIndex); i[i4h"$0
return ps; 8u"U1
} 6u?>M9
}, true); E[OJ+ ;c
} uIY#e<)}G
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public List findAllByCriteria(final ]|#+zx|/D
"BAK !N$9
DetachedCriteria detachedCriteria){ g9OY<w5s]
return(List) getHibernateTemplate BqEI(c6
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().execute(new HibernateCallback(){ (xycJ`N
publicObject doInHibernate ?C]vS_jAh
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(Session session)throws HibernateException { pG_;$8Hc
Criteria criteria = k``_EiV4t
yER(6V'\iQ
detachedCriteria.getExecutableCriteria(session); >k|5Okq g
return criteria.list(); ^"E^zHM(
} L]7=?vN=8
}, true); ip\sXVR
} z>xmRs
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public int getCountByCriteria(final K&u_R
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DetachedCriteria detachedCriteria){ Z<oaK
Integer count = (Integer) *9
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getHibernateTemplate().execute(new HibernateCallback(){ DmK57V4L^
publicObject doInHibernate xl{=Y< ;
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(Session session)throws HibernateException { :x3QRF
Criteria criteria = t}_r]E,{u
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detachedCriteria.getExecutableCriteria(session); 39c2pV[
return g_E$=j92v
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criteria.setProjection(Projections.rowCount P-[-pi@
I]|Pq
()).uniqueResult(); u$z`
} &md`$a/
}, true); + SzU
return count.intValue(); RIR\']WN
} x%=si[P
} 6dQ-HI*Y#
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用户在web层构造查询条件detachedCriteria,和可选的 !"AvY y9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 TJd)K$O>
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PaginationSupport的实例ps。 fy1|$d{'
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ps.getItems()得到已分页好的结果集 ]2A^1Del
ps.getIndexes()得到分页索引的数组 ;7*[Bcj.
ps.getTotalCount()得到总结果数 >fG3K`
ps.getStartIndex()当前分页索引 {L971W_L
ps.getNextIndex()下一页索引 2YL?,uLS
ps.getPreviousIndex()上一页索引 U)TUOwF
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zC:ASt
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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 n)/z0n!\
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一下代码重构了。 wVXS%4|v
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我把原本我的做法也提供出来供大家讨论吧: >gQ>1Bwvi
uh_RGM&
首先,为了实现分页查询,我封装了一个Page类: *tFHM &a
java代码: `cn#B
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/*Created on 2005-4-14*/ Eh`7X=Z7E
package org.flyware.util.page; Ufj`euY
m,28u3@r
/** ;]puq
* @author Joa _RYxD"my
* ;LfXi 8)
*/ T.F!+
publicclass Page { hW')Sp
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/** imply if the page has previous page */ RU{twL.B
privateboolean hasPrePage; ? V1*cVD6i
0JS?; fk
/** imply if the page has next page */ t,Lrfv])
privateboolean hasNextPage; udH7}K v
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/** the number of every page */ 234p9A@
privateint everyPage; LrfVh-}|:Y
1nM
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/** the total page number */ <{p4V|:
privateint totalPage; 4KAZ ':
;}WeTA_-[
/** the number of current page */ mUC)gA/
privateint currentPage; PQt")[
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/** the begin index of the records by the current )}R0Y=e
yN0Vr\r2
query */ ]! &FKy
privateint beginIndex; BZ#(
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pad*oPH,
/** The default constructor */ &E F!OBR
public Page(){ \sixI;-2
2DrM3ZU8
} 9=M$AB
;+_:,_
/** construct the page by everyPage YqD=>P[O
* @param everyPage ^e5=hH-%
* */ +/7?HGf
public Page(int everyPage){ u#fM_>ML
this.everyPage = everyPage; /62!cp/F/D
} ,KZ~?3$yj
!n!*/[}X
/** The whole constructor */ 8nqG<!,q
public Page(boolean hasPrePage, boolean hasNextPage, s[*rzoA
.sW|Id )
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int everyPage, int totalPage, Wb_J(!da
int currentPage, int beginIndex){ ~_)^X
this.hasPrePage = hasPrePage; @;4zrzQi7
this.hasNextPage = hasNextPage; G>=*yqo
this.everyPage = everyPage; octL"t8w
this.totalPage = totalPage; C&f=
ywi0
this.currentPage = currentPage; l30EKoul)
this.beginIndex = beginIndex; Wi<m{.%\E
} @{e}4s?7od
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/** =Bey gT^
* @return Jr4Ky<G_i
* Returns the beginIndex. uZYF(Yu
*/ @bLy,Xr&
publicint getBeginIndex(){ B@))8.h]
return beginIndex;
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} gg/-k;@ Rf
iVr J Q
/** v~C
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* @param beginIndex 8d{0rqwNE
* The beginIndex to set. L{\8!51L
*/ Hio0HL-
publicvoid setBeginIndex(int beginIndex){ S+6.ZZ9c
this.beginIndex = beginIndex; ,THw"bm
} {uFO/
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/** V &T~zh1
* @return MJ)RvNF
* Returns the currentPage. D)P ._?
*/ VGN5<?PrN
publicint getCurrentPage(){ `RW HN/U
return currentPage; Z\rwO>3
} 4"ZP 'I;
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/** _61gF[r4!Y
* @param currentPage gVuFHHeUz
* The currentPage to set. VQ@
*/ e%M;?0j
publicvoid setCurrentPage(int currentPage){ Y|qTyE%
this.currentPage = currentPage; {S\{Ii6
} ?j.,Nw4FC
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/** ]/6z;
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* @return Ix}sK"}[n
* Returns the everyPage. e`s
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*/ >R_&Ouh:
publicint getEveryPage(){ G_JA-@i%
return everyPage; 372rbY
} u#~RkY7s
; 2#y7!
/** Jpq~
* @param everyPage t?gic9
q
* The everyPage to set. T!{w~'=F
*/ fOrH$?
publicvoid setEveryPage(int everyPage){ kZ:ZtE
this.everyPage = everyPage; re<{
>
} t@;p
wlvgg
/** Z{d^-
* @return ajT*/L!0_
* Returns the hasNextPage. 3?yg\
*/ @mBQ?;qlK
publicboolean getHasNextPage(){ Y=KT eYW`
return hasNextPage; UkC!1Jy
} -2[a2^a'
vr l-$ii
/** X?',n
1
* @param hasNextPage }.(B}/$u
* The hasNextPage to set. bJ%h53
*/ 3"e,qY
publicvoid setHasNextPage(boolean hasNextPage){ |df Pki{
this.hasNextPage = hasNextPage; xo&_bMO
} mJnIwdW*
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/** 3d]S!=4H"
* @return J8(lIk:e
* Returns the hasPrePage. &z3o7rif$
*/ 0d&6lqTo
publicboolean getHasPrePage(){ aXYY:;
return hasPrePage; Y.UFbrv
} 'H!Uh]!
R n[cW5Y<
/** am'7uy!ka~
* @param hasPrePage p6@)-2^
* The hasPrePage to set. n\DV3rXI9
*/ {tZ.v@
publicvoid setHasPrePage(boolean hasPrePage){ m
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this.hasPrePage = hasPrePage; {\5
} =T@1@w
)10+@d
/** # W']6'O
* @return Returns the totalPage.
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* \b x$i*
*/ f6Ah6tb
publicint getTotalPage(){ CTa57R
return totalPage; oc`H}Wvn
}
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>bW#Zs,6
/** `^&OF uee
* @param totalPage abj Q)=u
* The totalPage to set. Q
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*/ KRzAy)8
publicvoid setTotalPage(int totalPage){ Yq
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this.totalPage = totalPage; %u'ukcL7
} 6&x@.1('z
7:1Lol-V
} QWYJ*
m_]Y{3C
Xv^qVn4
i/4>2y9/F4
tD)J*]G
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ga +dt
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个PageUtil,负责对Page对象进行构造: K0>zxqY
java代码: yN-9[P8C
0(HU}I
f:}
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/*Created on 2005-4-14*/ "to;\9lP
package org.flyware.util.page; 0 H:X3y+
WsB ?C&>x
import org.apache.commons.logging.Log; U xGApK=X
import org.apache.commons.logging.LogFactory; >[#f\bG>
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/** M= (u]%\
* @author Joa !Uo4,g6r+
* "y}5;9#,
*/ `c$V$/IT
publicclass PageUtil { 9.#<b|g
mfr|:i
privatestaticfinal Log logger = LogFactory.getLog z{QqY.Gu{G
~"!fP3"e
(PageUtil.class); B@ EC5Ap*
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/** %N._w!N<5n
* Use the origin page to create a new page 6gDN`e,@
* @param page L4W5EO$
* @param totalRecords z$sT !QL~
* @return 9 68Ez
*/ Pq$n5fZC!
publicstatic Page createPage(Page page, int 1% ` Rs
?r4>" [
totalRecords){ =3P)q"
return createPage(page.getEveryPage(), %|oym.-I6
At;LO9T3z
page.getCurrentPage(), totalRecords); h?U
O&(
} "{t$nVJ
P%n>Tg80M
/** a<e[e>
* the basic page utils not including exception ]SEZaT
sI2^Qp@O1
handler h(DTa
* @param everyPage QT}tvm@PMq
* @param currentPage <P<z N~i9j
* @param totalRecords .%-8 t{dt
* @return page c+ie8Q!
*/ o8MZiU1Xf
publicstatic Page createPage(int everyPage, int h";L
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currentPage, int totalRecords){ #'}*dy/
everyPage = getEveryPage(everyPage); ckn(`I
currentPage = getCurrentPage(currentPage); hy!3yB@
int beginIndex = getBeginIndex(everyPage, HzJz+ x:
]?4hyN
currentPage); (9)Q ' 'S
int totalPage = getTotalPage(everyPage, Q!3_$<5<E>
uY*L,j^)
totalRecords); *Pr )%
boolean hasNextPage = hasNextPage(currentPage, i6Gu@( 8Q
* 4
n)
totalPage); >\8+:oS^
boolean hasPrePage = hasPrePage(currentPage); K
8O|?x]
/dHF6yW
returnnew Page(hasPrePage, hasNextPage, /bmN\I
everyPage, totalPage, a+QpM*n7Lq
currentPage, Ny#^&-K
Gc7=
beginIndex); '3;b@g,
} q^nVN#
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privatestaticint getEveryPage(int everyPage){ [Rb+q=z#
return everyPage == 0 ? 10 : everyPage; q3`u1S7Z7
} %so]L+r2!
wL[
M:
privatestaticint getCurrentPage(int currentPage){ ,zc(t<|-y
return currentPage == 0 ? 1 : currentPage; \M-OC5fQv
} O/LXdz0B
2an f$^[
privatestaticint getBeginIndex(int everyPage, int !r-F>!~
Q2>gU#
currentPage){ :Dp0?&_
return(currentPage - 1) * everyPage; F'Z,]b'st3
} 2AdDIVYC
KPki}'GO
privatestaticint getTotalPage(int everyPage, int CC`JZ.SO
$cgcX
totalRecords){ +ge?w#R
int totalPage = 0; tJmTBsn
2 E=L8<
if(totalRecords % everyPage == 0) ;VK.2^jW!
totalPage = totalRecords / everyPage; ~J]qP #C
else qP
,EBE
totalPage = totalRecords / everyPage + 1 ; '"Nr, vQo
~ri5zb20
return totalPage; naNghGQ
}
!@sUj
wuBPfb
privatestaticboolean hasPrePage(int currentPage){ d zMb5puH
return currentPage == 1 ? false : true; #9s,#
}
} (k P9hcV
xD 7]C|8o
privatestaticboolean hasNextPage(int currentPage, /{2,zW
kx CSs7J/
int totalPage){ 4ppz,L,4
return currentPage == totalPage || totalPage == JGZBL{8
n"8Yv~v*2j
0 ? false : true; EX"yxZ~
} ~6gPS
13
@F>D+=hS
[>9is=>o.
} >mkFV@`
jWgX_//!
YkADk9fE
A}w/OA97RO
?A0)L27UE&
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。 O0:q;<>z
|BYRe1l6l
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
.Y|!:t|
$Kd>:f=A
做法如下: 7$#u
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 kf9X$d6
xx $cnG
的信息,和一个结果集List: +ai<
q>+
java代码: 8,|k ao:
I 6O
g{LP7D;6
/*Created on 2005-6-13*/ )PZT4jTt
package com.adt.bo; 1H9!5=Ff
z!\*Y
=e
import java.util.List; r|Z{-*`
{G-kNU
import org.flyware.util.page.Page; afk>+4q
sRfcF`7
/** zeRyL3fnmb
* @author Joa m+9#5a-
*/ ;a3}~s
publicclass Result { |a@L}m
0 {mex4
private Page page; Zd&S@Z
('~LMu_
private List content; [Qr"cR^
!m$jk2<
/** ,,TnIouy
* The default constructor $Q0n
*/ 31)&vf[[
public Result(){ fy$1YI>!Q
super(); 6B-16
} t,'<gI
h];I{crh
/** cCX*D_kCB
* The constructor using fields (sj,[
* s^SJY{
* @param page ]^]wP]R_
* @param content kVL.PY\K
*/ }WV:erg`
public Result(Page page, List content){ `X8F`5&U\f
this.page = page; V.Mry`9-
this.content = content; TC"<g
} QW"! (`K
MQ4KdqgP
/** 05[SC}MCA
* @return Returns the content. %)wjR/o
*/ \v/[6&|X0s
publicList getContent(){ Ss`LLq0LO
return content; W!<U85-#S
} j.YA2mr
n`KY9[0U=
/** @pxcpXCy
* @return Returns the page. vv7I_nK?
*/ OJxl<Q=z
public Page getPage(){ }\LQ3y"[
return page; 8i pez/
} Debv4Gr;^
=lC7gS!U
/** snJ129}A
* @param content 7o4\oRGV
* The content to set. 3a|\dav%
*/ m kexc~l
public void setContent(List content){ oU/5 a>9~
this.content = content; nP$9CA
} ElXFeJ%[G
c%&>p||
/** IK]d3owA
* @param page y}H!c;
* The page to set. \Cj B1]I
*/ Y$zSQ_k;U
publicvoid setPage(Page page){
@8
6f
this.page = page; NO3/rJ6-
} j#6.Gq
} n*$ g]G$
Je{ykL?N
:pUtSs7p}
ME dWLFf
UI#h&j5pW
2. 编写业务逻辑接口,并实现它(UserManager, W4N{S.#!
=#\:}@J5I
UserManagerImpl) If.r5z9
java代码: Q20%"&Xp]
he4(hX^
Y0>y8UV
/*Created on 2005-7-15*/ BzzTGWq\
package com.adt.service; :Sma`U&
g5yJfRLxp
import net.sf.hibernate.HibernateException; ]?*wbxU0
7 3m1
import org.flyware.util.page.Page; ceV}WN19l
l,8##7
import com.adt.bo.Result; MPV5P^@X
nR~(0G,H
/** nK,w]{<wG!
* @author Joa hQi2U
*/ }*-@!wc-N
publicinterface UserManager { 9iq_rd]
o@Oqm> ]SS
public Result listUser(Page page)throws nlYNN/@"
OCUr{Nh
HibernateException; kl`W\t F
HhpDR
} 68
sB)R
;fJ.8C
TN.rrop`#g
uc=B,3
Fp:'M X
java代码: @VBcJ{e,
"#] $r
:0ep(<|;
/*Created on 2005-7-15*/ OnK4] S5
package com.adt.service.impl; R8Tx[CJ5
xmG<]WF>E
import java.util.List; G#CXs:1pd+
liZxBs
:%i
import net.sf.hibernate.HibernateException; ?0SEMmp`H
#?E"x/$Y6
import org.flyware.util.page.Page; RpK@?[4s
import org.flyware.util.page.PageUtil; g*Phv|kI
rZF*q2?
import com.adt.bo.Result; :t[_:3@
import com.adt.dao.UserDAO; KP"+e:a%
import com.adt.exception.ObjectNotFoundException; Rv=YFo[B
import com.adt.service.UserManager; ;,TFr}p`
Th%zn2R B
/** >V937
* @author Joa yuVs
YV@"
*/ GmG5[?)
publicclass UserManagerImpl implements UserManager { AdmC&!nH
:+Z%; Dc
private UserDAO userDAO; =I4lL]>
>Q/Dk7 #
/** VQs5"K"
* @param userDAO The userDAO to set. [e
q&C_|D
*/ :U\tv[
publicvoid setUserDAO(UserDAO userDAO){ :Al!1BJQ
this.userDAO = userDAO; dI2
V>vk
} dveiQ
lk!@?
/* (non-Javadoc) CAe!7HiR
* @see com.adt.service.UserManager#listUser ;`Z{7'^U
GVz6-T~\>
(org.flyware.util.page.Page) Zc yc*{DS
*/ ?5p>BER?
public Result listUser(Page page)throws i?/qY&~
q| 7(
HibernateException, ObjectNotFoundException { ==B6qX8T
int totalRecords = userDAO.getUserCount(); ,_P-$lB
if(totalRecords == 0) b'y%n
throw new ObjectNotFoundException edD)TpmE,
No$3"4wk
("userNotExist"); bLL2
page = PageUtil.createPage(page, totalRecords); FsPw1A$y
List users = userDAO.getUserByPage(page); :DNjhZ
returnnew Result(page, users); RNL9>7xV
} D=$)n_F
=%7-ZH9
} /xQTxh1;K
Kq!3wb;
}b}m3i1
~~.}ah/_d
ta0|^KAA
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _GPe<H
<%^&2UMg
询,接下来编写UserDAO的代码: *i,%,O96Nz
3. UserDAO 和 UserDAOImpl: xLE)/}y_7H
java代码: vI?, 47Hj+
@CoIaUVP
lYIH/:T
/*Created on 2005-7-15*/ `XKLU
package com.adt.dao; iCoX&"lb
"tZe>>I
import java.util.List; e.%nRhSs3
8|^7ai[am
import org.flyware.util.page.Page; WxDh;*am:
AX INThJ
import net.sf.hibernate.HibernateException; ]|@^1we
JJnH%Q
/** <q836]aaA
* @author Joa XZf$K _F&M
*/ jdN`mosJ
publicinterface UserDAO extends BaseDAO { YUb_y^B^
4| f*eO
publicList getUserByName(String name)throws Y2TtY;
,6/V"kqIP
HibernateException; TC('H[
]
ZcsZ$qt^
publicint getUserCount()throws HibernateException; y5r4&~04
R_KH"`q
publicList getUserByPage(Page page)throws $qiya[&G4
"Q<MS'a
HibernateException; #tHK"20
cL ]1f
} ~u{uZ(~
zA 3_Lx!
kM6
Qp
NbobliC=
|)&%A%m
java代码: GyIV
Hby
#cJ@uqR
7$b1<.WX
/*Created on 2005-7-15*/ _!6jR5&r,
package com.adt.dao.impl; f3;5Am
>?b!QU*a
import java.util.List; #WuBL_nZ~
`uFdwO'DD
import org.flyware.util.page.Page; {ax:RUQxy
wJ]d&::@h
import net.sf.hibernate.HibernateException; oDR%\VY6T
import net.sf.hibernate.Query; \bF{-" 7.
H|*m$|$,
import com.adt.dao.UserDAO; [
3Gf2_
8}[).d160
/**
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* @author Joa T%Lx%Qn
*/ .>S!ji
public class UserDAOImpl extends BaseDAOHibernateImpl Ba,`TJ%y
eRYK3W
implements UserDAO { \RiP
*hx
/* (non-Javadoc) vdZW%-A&\
* @see com.adt.dao.UserDAO#getUserByName d$RIS+V
NUZl`fu1Z4
(java.lang.String) 6<]lW
*/
2iOV/=+
publicList getUserByName(String name)throws -~0^P,yQ
^#$n~]s
HibernateException { /(cPfZZ
String querySentence = "FROM user in class %;_MGae
pb}*\/s
com.adt.po.User WHERE user.name=:name"; |N2#ItBbW
Query query = getSession().createQuery t!XwW$@
*T/']t
(querySentence); *p U x8yB
query.setParameter("name", name); m@c)Xci
return query.list(); %Zi} MPx
} 29KiuP
WJ#[LF!e
/* (non-Javadoc) ,prf;|e?
* @see com.adt.dao.UserDAO#getUserCount() {mg2pfhB!
*/ SU0
hma8
publicint getUserCount()throws HibernateException { v+XJ*N[W
int count = 0; HtFDlvdy]
String querySentence = "SELECT count(*) FROM aOp\91
;TYBx24vD'
user in class com.adt.po.User"; uFE)17E
Query query = getSession().createQuery C]6O!Pb0
CTb%(<r
(querySentence); oU8q o-J1H
count = ((Integer)query.iterate().next I,tud!p`
{FkF
()).intValue(); &Jj<h: *
return count; /wp6KXm
} Y4-t7UlS;
'DR!9De
/* (non-Javadoc) eFgA 8kY)
* @see com.adt.dao.UserDAO#getUserByPage ^[[P*NX3
;uJMG
(org.flyware.util.page.Page) 7! Nsm
*/ Tk}]Gev
publicList getUserByPage(Page page)throws j%kncGS
HN"Z]/5j
HibernateException { TOt dUO
String querySentence = "FROM user in class &
21%zPm
By|4m
com.adt.po.User"; .Mbz3;i0
Query query = getSession().createQuery ]gOy(\B
>Tgv11[
(querySentence); =bOW~0Z1
query.setFirstResult(page.getBeginIndex()) ]Ze1s02(
.setMaxResults(page.getEveryPage()); \e*]Ls#jS
return query.list(); 0kh6@y3
} %J(:ADu]
I9Xuok!0>=
} ye&;(30Oq
9*gZ-#
~ljXzD93Z
0J9x9j`&j
lA]8&+,ZM
至此,一个完整的分页程序完成。前台的只需要调用 ?,mmYW6TjB
kP:!/g
userManager.listUser(page)即可得到一个Page对象和结果集对象 iS^QTuk3%
uRvP hkqm
的综合体,而传入的参数page对象则可以由前台传入,如果用 /v{I
)nkY_'BV
webwork,甚至可以直接在配置文件中指定。 4(+PD&_J
%b$>qW\*&
下面给出一个webwork调用示例: )A6<c%d =x
java代码: q V=!ORuj
)9g2D`a4
|Cv!,]9:r
/*Created on 2005-6-17*/ (.:e,l{U%
package com.adt.action.user; y[;>#j$
l?e.9o2-
import java.util.List; E GU2fA7x
(PLUFT
import org.apache.commons.logging.Log; 2/?|&[
import org.apache.commons.logging.LogFactory; `Di{}/2
import org.flyware.util.page.Page; J.a]K[ci
O.? JmE
import com.adt.bo.Result; V~GDPJ+
import com.adt.service.UserService; llq<egZpm
import com.opensymphony.xwork.Action; "oyo#-5z
Wtnfa{gP%
/** 10&8-p1/mc
* @author Joa VbYdZCC
*/ c<~H(k'+c
publicclass ListUser implementsAction{ CIWO7bS
W?&%x(6M
privatestaticfinal Log logger = LogFactory.getLog ]Ljf?tk
mFeP9MfJ
(ListUser.class); :FF=a3/"6
" bG2:
private UserService userService; JF]JOI6.e
4+n\k
private Page page; 9r9NxKuAO
\U0Q<ot/7
privateList users; ceA9){
_1^'(5f$
/* YSMAd-Ef-
* (non-Javadoc) >_}
I.\X
* !-bB559Nv
* @see com.opensymphony.xwork.Action#execute() KvSG;
*/ }H4RR}g
publicString execute()throwsException{ <@}9Bid!o
Result result = userService.listUser(page); jIyQ]:* p
page = result.getPage(); M5B# TAybC
users = result.getContent(); pAEx#ck
return SUCCESS; Dq xs+
} u2I Cl
BUFv|z+H
/** =a!=2VN9y
* @return Returns the page. & kIFcd@
*/ }u|q0>^8
public Page getPage(){ $]1=\I
return page; 6*?F @D2&
} $>gFf}#C
E^PB)D(.
/** X]=t>
* @return Returns the users. l6B@qYLZ
*/ 3$w65=
publicList getUsers(){ ^aQ"E9
return users; g}i61(
} ]_Xlq_[/r
Ru XC(qcq
/** v=k$A
* @param page =43auFY-P
* The page to set. !wNO8;(
*/ ToQ"Iy?
publicvoid setPage(Page page){ iE{&*.q_}>
this.page = page; ?upM>69{
} %\DX#.
M2|is ~
/** l,:F
* @param users t5zKW _J7
* The users to set. d3Rw!slIq
*/ P4?glh q#
publicvoid setUsers(List users){ 7rA;3?p)
this.users = users; ]9XDS[<2`
} N7_"H>O$0U
M;NX:mX9
/** q;U,s)Uz^
* @param userService ~Z+%d9ode
* The userService to set. m,S{p<-h
*/ 2%>FR4a
publicvoid setUserService(UserService userService){ /> Nt[o[r
this.userService = userService; P$sxr
} m68*y;#
} S$k&vc(0
]d`VT)~vje
DJ%PWlK5
h$=2 p5'-
<or2
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,
9akH
!wp3!bLp
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 }i2V.tVB-
5?L<N:;J_
么只需要: >{Tm##@,k
java代码: Z=
!*e~j@
zT[!o
j7
LF7SS;&~f
<?xml version="1.0"?> %UM
*79
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 8X0z~&
(ik\|y% A
1.0//EN" "http://www.opensymphony.com/xwork/xwork- >j`qh:^
s<Fl p
1.0.dtd"> Wl Sm
Sc
<xwork> ZC}QId
T)})
pt!V
<package name="user" extends="webwork- `lPfb[b
ipILG4
interceptors"> 5-G@L?~Vw
"\=U)CJ
<!-- The default interceptor stack name "vGW2~*)
D-4f.Tq4#
--> JLi|Td"1%
<default-interceptor-ref ty`DJO=Omj
CP{cAzHO
name="myDefaultWebStack"/> @I*{f
|CzSU1ma
<action name="listUser" ]_f<kW\1*
'\GbmD^F
class="com.adt.action.user.ListUser"> v}x&?fU `
<param G9:l'\
V>
bCKtf&
name="page.everyPage">10</param> j5ve2LiFV%
<result EIQ
p>|5
-(#iIgmP
name="success">/user/user_list.jsp</result> Q&V;(L62!
</action> =ruao'A
9C\Fq-
</package> p^_yU_
kwA$Z!Rn
</xwork> {GO#.P"
+{UcspqM
x;')9/3
qv*^fiT
e]tDy0@
h@h! ,;
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 YF:L)0H'O
@vB!u[{
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ][]
Tqk\XILG N
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iyp=lLk
yA>nli=
z~Q>V]a>;
4{l,
3t6LT
我写的一个用于分页的类,用了泛型了,hoho 9I/N4sou
w\brVnt
java代码: t_suF$
Ki~1qu:
yOg+iFTr
package com.intokr.util; O#u=c1
?:
,u
g@f-T
import java.util.List; AFfAtu
0AV c
/** \_U$"/$4VH
* 用于分页的类<br> Z:7fV5b(
* 可以用于传递查询的结果也可以用于传送查询的参数<br> z"4~P3>{g
* BX^tR1
* @version 0.01 sse.*75U
* @author cheng L~>i,
*/ {u9}bx'<
public class Paginator<E> { M:6"H%h,W
privateint count = 0; // 总记录数 I0RvnMw
privateint p = 1; // 页编号 KK%M~Y+tU'
privateint num = 20; // 每页的记录数 TBrPf-Xr
privateList<E> results = null; // 结果 Fr$5RAyg
2wgg7[tGi
/** pU7lnS[
* 结果总数
v<:R#
*/ O,A{3DAe0
publicint getCount(){ ~3S~\0&|
return count; -B\HI*u
} zkdetrR
:#~j:C|
publicvoid setCount(int count){ ++#5
this.count = count; {GcO3G#FZ
} ,i@:5X/t
ff1c/c/
/** f>Jr|#k
* 本结果所在的页码,从1开始 ;xs"j-r/
* 50C
* @return Returns the pageNo. ]]juN
*/ @Pzu^
publicint getP(){ E=w1=,/y
return p; 14'45
} .k
\@zQ|Ta
u=_mvN
/** t@Nyr&|D
* if(p<=0) p=1 ]}(H0?OQR
* P}G+4Sk
* @param p D{~fDRR
*/ U!Z,xx[]
publicvoid setP(int p){ A$xF$l
if(p <= 0) (/*]?Ehd
p = 1; FtC^5{V+V
this.p = p; r{%qf;
} >u8gD6X
*C=>X193U
/** *U\`CXn;
* 每页记录数量 ;l-!)0U
*/ &q|K!5[k
publicint getNum(){ }XM(:|8J,
return num; x7x\Y(@
} 'anG:=
lR6x3C
H@
/** pQ<Y:-`c
* if(num<1) num=1 ig':%2V/
*/ Oh\<VvZuN
publicvoid setNum(int num){ A7hVHxNJ-
if(num < 1) g!z&~Z:
num = 1; 1q1jZqno
this.num = num; \A6B,|@
} :'&brp3ii=
Zdo'{ $
/** HuKc9U'7A
* 获得总页数 k/gZ,
*/ Q7COQ2~K
publicint getPageNum(){
H =^`!
return(count - 1) / num + 1; Sw^u3
} ">jj
{Wu$YWE*sx
/** yw3$2EW
* 获得本页的开始编号,为 (p-1)*num+1 Y<ql49-X
*/ 9
ea\vZ
publicint getStart(){ ~B(4qK1G
return(p - 1) * num + 1; f_Av3
} X=8{$:
p >t#@Eu|
/** &&RimoIeo
* @return Returns the results. @\P;W(m.i
*/ 6ez<g
Uf
publicList<E> getResults(){ M$8^91%4B
return results; o W Nh@C
} tWa)_y
8rS:5:Hi
public void setResults(List<E> results){ X~,aNRy
this.results = results; _v=SH$O+
} Q=20IQp
z4]api(xZ
public String toString(){ jc f #6
StringBuilder buff = new StringBuilder EeRX+BM,
q,eVjtF
(); BV upDGh3
buff.append("{"); !*. -`$x
buff.append("count:").append(count); V2|aN<Sx<
buff.append(",p:").append(p); [ $n_6
buff.append(",nump:").append(num); ?+a,m# Yx
buff.append(",results:").append !|S43i&p
VsE9H]v
(results); vVe';|8v
buff.append("}"); Ab"@714@
return buff.toString(); ~-J]W-n
} >R!jB]5
1sdLDw_)p
} vv+z'(l
Mz~D#6=
6U,O*WJ%e