Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 dRi5hC$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 5J2=`=FK
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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 zYY$D.
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 (X[CsaXt
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。 %+)o'nf"U
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分页支持类: .7NNT18
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java代码: Sh6JF574T
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package com.javaeye.common.util; Q/ms]Du
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import java.util.List; wC_l@7t
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publicclass PaginationSupport { wXMDh$
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publicfinalstaticint PAGESIZE = 30; ?>c=}I#Ui-
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privateint pageSize = PAGESIZE; TjMe?p
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privateList items; '_\;jFAM
#1 1NPo9
privateint totalCount; xT&(n/
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privateint[] indexes = newint[0]; OO dSKf8
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privateint startIndex = 0; /M;#_+VK<
@ V08U!
public PaginationSupport(List items, int Rlnbdb;!k
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totalCount){ \!vN
setPageSize(PAGESIZE); {rfF'@[
setTotalCount(totalCount); \<Sv3xy&O
setItems(items); uwf
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setStartIndex(0); T{qTj6I
} Jj~EiA
wbDM5%
public PaginationSupport(List items, int O%g$9-?F0
4(}J.-B
totalCount, int startIndex){ J:uW`R
setPageSize(PAGESIZE); ?Xdak|?i
setTotalCount(totalCount); \^( 0B8|w
setItems(items); iv`O/T
setStartIndex(startIndex); Pq*s{
} 0]QRsVz+
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public PaginationSupport(List items, int <FMq>d$\
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totalCount, int pageSize, int startIndex){ MuoF FvAA
setPageSize(pageSize); Fhv/[j^X
setTotalCount(totalCount); 0;S, tJg
setItems(items); >hBxY]< \
setStartIndex(startIndex); PB%-9C0
} )X4K2~k*
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publicList getItems(){ 5@*'2rO&!
return items; EbeI{-'aF
} '$4O!YI9@
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publicvoid setItems(List items){ %Qg+R26U
this.items = items; ?JL7=o
X
} vvUSeG\n#j
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publicint getPageSize(){ 8Ll[ fJZA
return pageSize; 7+x? "4
} R52I=
a5,*
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publicvoid setPageSize(int pageSize){ 2[0JO.K
4
this.pageSize = pageSize; I^o!n5VM
} G:x*BH+
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publicint getTotalCount(){ ?+T^O?r|O
return totalCount; !`!| Zw
} s2j['g5
Vh}SCUof'
publicvoid setTotalCount(int totalCount){ u?sVcD[
if(totalCount > 0){ E}%hz*Q)(
this.totalCount = totalCount; }j,[ 1@S
int count = totalCount / p ?wI9GY
3\T2?w9u(
pageSize; P/&]?f0/
if(totalCount % pageSize > 0) 7JSNYTH
count++; ]*7Y~dO
indexes = newint[count]; r>bJ%M}
for(int i = 0; i < count; i++){ UT}i0I9
indexes = pageSize * /?';
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i; 5k|9gICyd*
} xkOpa,=FI
}else{ fO#vF.k%
this.totalCount = 0; fwzb!"!.@
} AIA6yeaU
} <AJ97MLcc
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publicint[] getIndexes(){ t4?DpE
return indexes; [pVamE
} C"IKt
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publicvoid setIndexes(int[] indexes){ G%d
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this.indexes = indexes; ?WE
} b,8{ X<
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publicint getStartIndex(){ a1Qv@p^._b
return startIndex; M:5b4$Qh<
} {}:ToIp
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publicvoid setStartIndex(int startIndex){ F[ewn/]n
if(totalCount <= 0) s`>[F@N7.o
this.startIndex = 0; F: mq'<Q
elseif(startIndex >= totalCount) y!]CJigpZ
this.startIndex = indexes /PsnD_s]5
vX ] Gf4,
[indexes.length - 1]; %c[ V
elseif(startIndex < 0) vzmc}y G
this.startIndex = 0; aM4k *|H?
else{ D-N8<:cA
this.startIndex = indexes h,"4SSL
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[startIndex / pageSize]; }%D^8>S
} {/pm<k=
} z3uW)GQ.
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publicint getNextIndex(){ CW<N: F.9
int nextIndex = getStartIndex() + =Fdg/X1
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pageSize; \rPbK+G.
if(nextIndex >= totalCount) In[Cr/&/Y
return getStartIndex(); } CfqG?)
else 0>zbCubPH
return nextIndex; j!3 Gz
} MeUaTJFEB
o: ;"w"G
publicint getPreviousIndex(){ Q?X>E3=U
int previousIndex = getStartIndex() - Gm\/Y:U
-ig6w.%lk
pageSize; >a}f{\Q
if(previousIndex < 0) GaSPJt
return0; ]Zmj4vK J
else `:axzCrCfR
return previousIndex; p ]d]QMu
} be +4junf
FHV-BuH5
} &~W:xg(jN
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抽象业务类 8(* [Fe9
java代码: v,ju!I0.
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/** x7$}8LZ"B
* Created on 2005-7-12 `]W|8M
*/ &?(?vDFfZ
package com.javaeye.common.business; g1(IR)U!z
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import java.io.Serializable; mrw=T.
import java.util.List; k1!@^A
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import org.hibernate.Criteria; G["c\Xux
import org.hibernate.HibernateException; hvaSH69*m
import org.hibernate.Session; !@v7Zu43,
import org.hibernate.criterion.DetachedCriteria; X*\J_
import org.hibernate.criterion.Projections; V 0rZz
import d N$Tf
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org.springframework.orm.hibernate3.HibernateCallback; ?F3h)(}
import pfI"36]F
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org.springframework.orm.hibernate3.support.HibernateDaoS 7"C$pm6
y_?Me]
upport; .;N 1N^
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import com.javaeye.common.util.PaginationSupport; P ! _rEV
)h)]SF}
public abstract class AbstractManager extends r%+V8o
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HibernateDaoSupport { v%iflCK
KGFv"u{
privateboolean cacheQueries = false; eYvWZJa4
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privateString queryCacheRegion; Sb82}$sO
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publicvoid setCacheQueries(boolean ]@u6HH~^
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cacheQueries){ )z28=%g
this.cacheQueries = cacheQueries; VB*oGG
} =UfsL%
#6HA\dE
publicvoid setQueryCacheRegion(String CmoE_8U>
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queryCacheRegion){ :x4|X8>
this.queryCacheRegion = hJpxf,?'K
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queryCacheRegion; %_%Q8,W
} LQRQA[^
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publicvoid save(finalObject entity){ Ay0U=#XP
getHibernateTemplate().save(entity); 4i(JZN?
} NUWDc]@J*
st:`y=F_
publicvoid persist(finalObject entity){ %1xb,g KO
getHibernateTemplate().save(entity); &&8IU;J
} ?!d&E?9\
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publicvoid update(finalObject entity){ !C3MFm{B
getHibernateTemplate().update(entity); S79;^X
} %,@e^3B
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publicvoid delete(finalObject entity){ j2StXq3
getHibernateTemplate().delete(entity); q=Sgk>NA
} yy i#Mo
,
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publicObject load(finalClass entity, IID-k
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finalSerializable id){ c|B.n]Z
return getHibernateTemplate().load \F/hMXDlJ
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(entity, id); ( u\._Gwsx
} (3Two}
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publicObject get(finalClass entity, 1Z+8r
@ hiCI.?X
finalSerializable id){ C'.L20qW
return getHibernateTemplate().get mGJKvJF
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(entity, id); w[zjerH3
} ;o2$
Q
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publicList findAll(finalClass entity){ (_mnB W
return getHibernateTemplate().find("from Dwr)0nk
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" + entity.getName()); Wz49i9e+d
} &_dt>.
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publicList findByNamedQuery(finalString eg\v0Y!rI
)wam8k5
namedQuery){ }Gz~nf%
return getHibernateTemplate ;c-(ObSm
|:q=T
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().findByNamedQuery(namedQuery); DCIxRPw
} "7'J&^|
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publicList findByNamedQuery(finalString query, /YP{,#p
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finalObject parameter){ 3G,Oba[$<
return getHibernateTemplate 8uc1iB
v5!d$Vctu
().findByNamedQuery(query, parameter); TJ_$vI
} QRc{vUR&
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publicList findByNamedQuery(finalString query, "CSsCA$/
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finalObject[] parameters){ "bFTk/
return getHibernateTemplate &zl|87M
+%zAQeb
().findByNamedQuery(query, parameters); dpAjR
} 4ni<E*
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publicList find(finalString query){ nt 81Bk=
return getHibernateTemplate().find }iXDa?6%
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(query); hm84Aq= f
} |{BIHgMh
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publicList find(finalString query, finalObject wKtl+}}
9_# >aOqL
parameter){ /f:dv?!km
return getHibernateTemplate().find Q8:Has
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(query, parameter); 'DY`jVwa
} j~2{lCT
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public PaginationSupport findPageByCriteria $:=A'd2
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(final DetachedCriteria detachedCriteria){ *rM^;4Zt
return findPageByCriteria WKts[Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); )JDs\fUE
} u!!Y=!y*<
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public PaginationSupport findPageByCriteria :By?O"LQ
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(final DetachedCriteria detachedCriteria, finalint \s/s7y6b+
v6=RY<l"m
startIndex){ G! ]k#.^A,
return findPageByCriteria ;\a
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$h2){*5E{
(detachedCriteria, PaginationSupport.PAGESIZE, 8|):`u
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startIndex); ~qcNEl\-y
} -|J"s$yO4
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public PaginationSupport findPageByCriteria G<At_YS
@E;=*9ek{u
(final DetachedCriteria detachedCriteria, finalint Y#!UPhg<
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pageSize, FK:;e
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finalint startIndex){ d:ARf
return(PaginationSupport) YNLV9.P6
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getHibernateTemplate().execute(new HibernateCallback(){ aO]ZZleNS
publicObject doInHibernate x^HGVWw_
qOe+ZAJ{%N
(Session session)throws HibernateException { w&$`cD
Criteria criteria = udxFz2>_l$
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detachedCriteria.getExecutableCriteria(session); nc~F_i=
int totalCount = 1/RsptN"v
=q>'19^Jx
((Integer) criteria.setProjection(Projections.rowCount yL%K4$z
*}]Nf
()).uniqueResult()).intValue(); K-e9>fmB#
criteria.setProjection Qt iDTr
^$%S &W
(null); 8B7cBkl:
List items = _p#CwExuy
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criteria.setFirstResult(startIndex).setMaxResults ;,$NAejgd
Ager$uC
(pageSize).list(); pM^9c7@!:
PaginationSupport ps = [DJ flCR&
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new PaginationSupport(items, totalCount, pageSize, JIOh#VNU
{FO;Yg'
startIndex); 3Vsc 9B"w
return ps; $k|g"9
} I[=j&rK`
}, true); 3t`P@nL0;
} R?v>Q` Qi
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public List findAllByCriteria(final ln$&``L
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DetachedCriteria detachedCriteria){ 5j:0Yt
return(List) getHibernateTemplate w3#Wh|LQ-
7q?9Tj3
().execute(new HibernateCallback(){ $iI]MV%=
publicObject doInHibernate P1zKsY,l$<
.9,zL=)Ba
(Session session)throws HibernateException { `kOD[*
Criteria criteria = .EpV;xq}
@_U;9)
detachedCriteria.getExecutableCriteria(session); ~oI1zNz/
return criteria.list(); &/mA7Vf>eR
} -c(F 1l
}, true); /4t j3B,
} 1lq(PGX)
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public int getCountByCriteria(final f_[<L
_= +V/=
DetachedCriteria detachedCriteria){ z|=}1;(.
Integer count = (Integer) =3|O%\
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getHibernateTemplate().execute(new HibernateCallback(){ ;ToKJ6hN|*
publicObject doInHibernate qi;f^9M%
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(Session session)throws HibernateException { #rxVd
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Criteria criteria = P6!jRC"52'
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detachedCriteria.getExecutableCriteria(session); e&7JpT
return bx<RV7>0
< XP9@t&
criteria.setProjection(Projections.rowCount .}'qUPNR
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()).uniqueResult(); UQ'\7OS
} O_$m!5ug
}, true); _Xn qb+
return count.intValue(); )A!>=2M`
} ^
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} ~(x;5{
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用户在web层构造查询条件detachedCriteria,和可选的 ,$;yY)x7U
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 SxdE?uCUS
7nHF@Y|*"
PaginationSupport的实例ps。 CK:y?
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ps.getItems()得到已分页好的结果集 B+[A]dgS
ps.getIndexes()得到分页索引的数组 V2$h8\a
ps.getTotalCount()得到总结果数 fQ/
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ps.getStartIndex()当前分页索引 ZN!4;
ps.getNextIndex()下一页索引 ,S'p%g
ps.getPreviousIndex()上一页索引 Ynp{u`?
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g0>,%b
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 G2t;DN(
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一下代码重构了。 g)s{IAVx
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我把原本我的做法也提供出来供大家讨论吧: hF@Gn/
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首先,为了实现分页查询,我封装了一个Page类: Gp4A.\7
java代码: U>V&-kxtV
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/*Created on 2005-4-14*/ k$H%.l;E
package org.flyware.util.page; yHHt(GM|o
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/** 6&bY} i^K
* @author Joa #<e\QE'!
* 1AG=%F|.
*/ cU{e`<xjA
publicclass Page { TUHi5K
q4}PM[K?=\
/** imply if the page has previous page */ Row)hx8
privateboolean hasPrePage; ]wKz E4Z/
;QW3CEaUq
/** imply if the page has next page */ J9\a{c;.
privateboolean hasNextPage; UJfEC0
*uo'VJI7_,
/** the number of every page */ uiJS8(Cb
privateint everyPage; Si_%Rr&jW
,y+$cM(
/** the total page number */ 6oLwfTy
privateint totalPage; O!Oumw,$
EhO|~A*R
/** the number of current page */ |1ST=O7.LH
privateint currentPage; oS7(s
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/** the begin index of the records by the current td4[[ /
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query */ RRGWC$>?
privateint beginIndex; ?0YCpn
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/** The default constructor */ uu}x@T@
public Page(){ _R.B[\r@
7zHh@ B:]
} -T&.kYqnb$
jS+AGE?5e
/** construct the page by everyPage Nnk@h
* @param everyPage Ux#x#N
* */ a)S+8uU
public Page(int everyPage){ `2`\]X_A{
this.everyPage = everyPage; ^2$ lJ
} w.lAQ5)I%\
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/** The whole constructor */ OvUI@,Ef
public Page(boolean hasPrePage, boolean hasNextPage, {X*^s5{;H
^)?d6nI
zH>hx5,k'X
int everyPage, int totalPage, o$[z],RO
int currentPage, int beginIndex){ {5d9$v7k4
this.hasPrePage = hasPrePage; M)+$wp
this.hasNextPage = hasNextPage; ,SQZD,3v4
this.everyPage = everyPage; `E!N9qI?t$
this.totalPage = totalPage; 7C$
5
this.currentPage = currentPage; ~}!3G
this.beginIndex = beginIndex; # [e
} N gLU$/y;
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/** rz"txN
* @return xB@|LtdO9;
* Returns the beginIndex. i~3u>CT
*/ W`"uu.~f
publicint getBeginIndex(){ ALEnI@0
return beginIndex; M;0]u.D*=
} /s-A?lw^2
,^gyH
\
/** RN)dS>$
* @param beginIndex ?-tVSRKQ
* The beginIndex to set. TZtjbD>B
*/ T]j.=|,d
publicvoid setBeginIndex(int beginIndex){ aA'|Rg,
this.beginIndex = beginIndex; dgDy5{_
} ->h6j
{CR 5K9
/** 5OO'v07b
* @return n39t}`WIl
* Returns the currentPage. YPzU-:3
*/ 2 o#,kGd
publicint getCurrentPage(){ S,U
Pl}KF
return currentPage; 2kv7UU#q2
} oQv3GpO
Dw7vv]+ S
/** p~ .8\bI=
* @param currentPage ~+<olss_
* The currentPage to set. /XudV2P-CA
*/ +dBz`WD
publicvoid setCurrentPage(int currentPage){ d*oUfiW
this.currentPage = currentPage; []0mX70N
} 0 a~HiIh
tTN?r 8
/** __[xD\ES
* @return k|BHnj
* Returns the everyPage. BYY RoE[P
*/ w_ {,<[#
publicint getEveryPage(){ <xJ/y|{
return everyPage; 4d_s%n?C
} ;f,c't@w
_U{([M>;
/** )RYG%
* @param everyPage kAM1TWbaVQ
* The everyPage to set. cst}Ibfi
*/ N$TL;T>
publicvoid setEveryPage(int everyPage){ KOg?FmD
this.everyPage = everyPage; f'q 28lVf
} ri1C-TJM)
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/** fbFX4?-
* @return -[OXSaf6
* Returns the hasNextPage. W>M~Sk$v
*/ ^). )
publicboolean getHasNextPage(){ -Q;#sJ?
return hasNextPage; `o79g"kxe
} s cdtWA
)'
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/** *n(> ^
* @param hasNextPage !3oKmL5
* The hasNextPage to set. >QHo@Zqj(
*/ 8hA^`Y
publicvoid setHasNextPage(boolean hasNextPage){ FFEfp.T1M
this.hasNextPage = hasNextPage; 4$,,Ppn
} j<pw\k{i
PN$
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/** &V7>1kD3
* @return cgC\mM4Nla
* Returns the hasPrePage. 4gdY`}8b^}
*/ o2-@o= F
publicboolean getHasPrePage(){ gM>=%/.
return hasPrePage; rOD1_X-
} i.iio-
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/** +VEU:1Gt
* @param hasPrePage 5/m$)wE
* The hasPrePage to set. |m,VTViv;i
*/ ,pq{& A
publicvoid setHasPrePage(boolean hasPrePage){ kE;O7sN
this.hasPrePage = hasPrePage; p4VqV6LwD
}
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/** }tST)=M`
* @return Returns the totalPage. ly4Qg\l
* ZF#Rej?
*/ lS{r=y_0.
publicint getTotalPage(){ _-cK{
return totalPage; cJn HW
} 77gysd\(
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/** ned2lC&'d>
* @param totalPage myQ&%M
gx
* The totalPage to set. w#G2-?aj
*/ Z&!!]"I
publicvoid setTotalPage(int totalPage){ "oc$
this.totalPage = totalPage; !)Ni dG
} Uhh
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F=@i6ERi
} i4Z4xTn
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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 va{#RnU
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个PageUtil,负责对Page对象进行构造: <"&'>?8j
java代码: 3"
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/*Created on 2005-4-14*/ ^nDal':*
package org.flyware.util.page; Yx?aC!5M
*:_~Nn9_R;
import org.apache.commons.logging.Log; :.IN?X
import org.apache.commons.logging.LogFactory; z[!x:# q8`
BD;H
/** H:oQ
* @author Joa o<VP'F{p
* h_
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*/ k
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publicclass PageUtil { oh}^?p
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privatestaticfinal Log logger = LogFactory.getLog ]W9B6G_
o42`z>~
(PageUtil.class); m/${8
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/** T)\NkM&
* Use the origin page to create a new page |4SW[>WT:
* @param page w7Dt1axB
* @param totalRecords IcoowZZ
* @return .LE+/n
*/ 3IyZunFT
publicstatic Page createPage(Page page, int RV!<?[
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totalRecords){ dtW0\^ .L
return createPage(page.getEveryPage(), Di.;<v#FL
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page.getCurrentPage(), totalRecords); :EB,{|m
} \|q-+4]@,
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/** WN0c%kz=
* the basic page utils not including exception B7 c[4
/yK"t<p
handler d.\PS9l
* @param everyPage /2w@K_Px6
* @param currentPage #]zhZW4
* @param totalRecords R+Lk~X^*l'
* @return page IK?]PmN4}
*/ Kq7C0)23
publicstatic Page createPage(int everyPage, int lPS*-p#IZ
8A/>JD3^
currentPage, int totalRecords){ Wm>b3:
everyPage = getEveryPage(everyPage); d pn3 (
currentPage = getCurrentPage(currentPage); oc;VIK)g]c
int beginIndex = getBeginIndex(everyPage, 1f;or_f#k?
E\!n49
currentPage); 5B|,S1b
int totalPage = getTotalPage(everyPage, C1ZyB"{
,i![QXZ
totalRecords); Lh!z>IWjOG
boolean hasNextPage = hasNextPage(currentPage, A\g%
{rfte'4;=
totalPage); @\$Keg=>:
boolean hasPrePage = hasPrePage(currentPage); T9y768%
r#I>_Utsy
returnnew Page(hasPrePage, hasNextPage, K P6PQgc
everyPage, totalPage, :B^mV{~
currentPage, Y eO-gY[b
q\_DJ)qpn
beginIndex); 9<Ag1l
} kxy]vH6m
2:~cJk{
privatestaticint getEveryPage(int everyPage){ 25&nwz
return everyPage == 0 ? 10 : everyPage; "cQvd(kug
} )-)pYRlO
w5Z2N[hy
privatestaticint getCurrentPage(int currentPage){ X\'E4
return currentPage == 0 ? 1 : currentPage; %t{Sb4XZ4k
} 4JSZ0:O
c
_p[yS
privatestaticint getBeginIndex(int everyPage, int t.L4%1OF
FdM<;}6T
currentPage){ NkoofhZ
return(currentPage - 1) * everyPage; ;,v.(Z ic
} :r-.r"[m-
&|NZ8:*+#
privatestaticint getTotalPage(int everyPage, int *@~`d*d
WN1Jm:5YV
totalRecords){ 15JsmA*Q
int totalPage = 0; qkiJH T
]qMH=>pOsj
if(totalRecords % everyPage == 0) iA&oLu[y3
totalPage = totalRecords / everyPage; W0U`Kt&~a
else F/xCG nP-
totalPage = totalRecords / everyPage + 1 ; wn{]#n=|l
:+<t2^)rD
return totalPage; p!QR3k.9s
} m}rh|x/?
K,G,di
privatestaticboolean hasPrePage(int currentPage){ Yu1QcFuy
return currentPage == 1 ? false : true; ),MU+*`
} 48:liR
A%P 8c
privatestaticboolean hasNextPage(int currentPage, '1Y<RD>x
\u{Jf'g
int totalPage){ "wC0eDf
return currentPage == totalPage || totalPage == Oe/73|
>U
0c`sb+?
0 ? false : true; \ hrBq^I
} nrI"k2oA@
ypgliq(
\)p4okpR
} Tw}@+-
0
-!?W
"k/;`eAP
H]VsOr
a^%8QJW
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。 )\RzE[Cb
$ 9S>I'
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 KBd7|,j
o*?[_{xW
做法如下: ! Zno[R
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >-UD]?>
"L ^TT2
的信息,和一个结果集List: Tavtr9L0XY
java代码: PG\\V$}A(
L-`(!j
A J<iM)l|
/*Created on 2005-6-13*/ }m9S(Wal
package com.adt.bo; 6{cybD`Ef&
MP6 \r
import java.util.List; =|^X$H
],!\IqO
import org.flyware.util.page.Page; xWd9%,mDNR
3s3a>
/** Z'voCWCd
* @author Joa qPp1:a"
*/
*K]>}
publicclass Result { cjCE3V9X
}K#iCby4
private Page page; 'hxs((['\
sZ0g99eX
private List content; tpN]evp|
Q,[rrG;?@
/** P}ehNt*($
* The default constructor e}{8a9J<%_
*/ k/$Ja;
public Result(){ N{?Tm`""
super(); \9dz&H
} cRs{=RGc
wJ;9),fL
/** ,\.YJD>z
* The constructor using fields ,apd3X%g
* ^4n2
-DvG
* @param page pkrl@jv >
* @param content 7AZ5%o
*/ 'US:Mr3
public Result(Page page, List content){ |NphG|
this.page = page; |HKHN?)
this.content = content; Bbn832iMUY
} , V0iMq
{|8:U}<#h
/** 8eg2o$k_,#
* @return Returns the content. (E2lv#[
*/ 7)ES!C
publicList getContent(){ Y/?DSo4G
return content; {[(W4NAlH
} aufcd57
E
6>1Fm8%V
/** rRF+\cP?.
* @return Returns the page. DYy@t^sC
*/ ND)M3qp2(
public Page getPage(){ BP7<^`i&
return page; "GIg|3
} rm7*l<v6
W#oEF/G
/** 4nVO.Ud0$X
* @param content g%<{G/Tz
* The content to set. ynOc~TN
*/ (
SC7m/
public void setContent(List content){ DbPBgD>Q
this.content = content; j,gM+4V^
} qB`0^V
&L[8Mju6
/** {kY`X[fvZ
* @param page gvwCoCbb
* The page to set. JY;#]'T\;
*/ //4p1^%
publicvoid setPage(Page page){ <7RkM
this.page = page; `gA5P %
} /ab K/8ZQ
} FHnHhB [
l#J>It\
lzQ&)7`
;#Crh}~
:` !mCW`Q-
2. 编写业务逻辑接口,并实现它(UserManager, 2-B8>-
+$pO
UserManagerImpl) (t]R#2{
java代码: PHB\)/
]>]H:NEq
3 `C3+
/*Created on 2005-7-15*/ .jG.90
package com.adt.service; !UPAEA
p_kTLNZd9
import net.sf.hibernate.HibernateException; hF{mm(qyv
::Ve ,-0
import org.flyware.util.page.Page; s#8{:ko
a}I z
import com.adt.bo.Result; E'6z7m.
EWvid4QEi
/** H6+st`{
* @author Joa C J}4V!;|
*/ ;-P:$zw9c
publicinterface UserManager { A5J#x6@
{UjIxV(J
public Result listUser(Page page)throws E<.{
v\
ZBh@%A
HibernateException; q?b)zeJ
I[YfF
} ohG43&g~
J5r
L7
>5YYij5Aj
^SES')x
r;s3(@[,@
java代码: #
v/aI*Rl
-Z#]_C{Y-)
RI].LB_
/*Created on 2005-7-15*/ u=?P*Y/|W
package com.adt.service.impl; \}_7^)S;
fTnyCaB
import java.util.List; .m
% x-i
c[eGpZ]
import net.sf.hibernate.HibernateException; enO=-#
E!]rh,mYK
import org.flyware.util.page.Page; 9hi(P*%q
import org.flyware.util.page.PageUtil; nHL>}Yg
Sv[_BP\^h
import com.adt.bo.Result; D_`)T;<Sp
import com.adt.dao.UserDAO; t`/RcAwA
import com.adt.exception.ObjectNotFoundException; (%^TTe
import com.adt.service.UserManager; /t2<OU9
U8 @*I>vA
/** OTbjZ(
* @author Joa "Kf~`0P
*/ Vam8NnZ|r
publicclass UserManagerImpl implements UserManager { E~U|v'GCd
CMB$RLf
private UserDAO userDAO; <UHf7:0V
K0bmU(Xxp
/** F;l<>|vG
* @param userDAO The userDAO to set. '48|f`8$
*/ j;c^pLUP
publicvoid setUserDAO(UserDAO userDAO){ !)1Zp*
this.userDAO = userDAO; ;C@^wI
} <.]& FPJ
*`/@[S2,cu
/* (non-Javadoc) fpC@3 itI
* @see com.adt.service.UserManager#listUser k.VOS0
\d8=*Zpz7
(org.flyware.util.page.Page) UmMYe4LQR
*/ <qZ+U4@I)
public Result listUser(Page page)throws [\y>&"uk
(4gQe6tA
HibernateException, ObjectNotFoundException { &^<T/PiR
int totalRecords = userDAO.getUserCount(); `SpS?mWA
if(totalRecords == 0) `'t;BXedz/
throw new ObjectNotFoundException ]fmf X
G(,~{N||
("userNotExist"); Z4tq&^ :c=
page = PageUtil.createPage(page, totalRecords); , X+(wp
List users = userDAO.getUserByPage(page); 833t0Ml1A/
returnnew Result(page, users); YZ+g<HXB
} mhSsOmJ5
SQ.Wj?W)
} uw&,pq
t|,Ex 7
QxL
FN(d
9`VF
[*
9
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _ o3}Ly}
u 9TlXn
询,接下来编写UserDAO的代码: ZOsn,nF
3. UserDAO 和 UserDAOImpl: Lu5.$b
java代码: )}lV41u
}J
lW\#
1Ac1CsK*
/*Created on 2005-7-15*/ P.P>@@+d
package com.adt.dao; <;"=ah7A
+Ea XS
import java.util.List; nAj2k
@=1``z#
import org.flyware.util.page.Page; W.<<azi
bME3" e{O
import net.sf.hibernate.HibernateException; e4LNnJU\|
.`RC,R`C
/** r $2
* @author Joa QyQ8M1m
*/ +.uk#K0o
publicinterface UserDAO extends BaseDAO { uwzT? C A6
G-<~I#k
publicList getUserByName(String name)throws 3S?+G)qKo
z#/*LP#oY
HibernateException; (o\~2e:
u{z{3fW_
publicint getUserCount()throws HibernateException; n-Y'LK40Os
</p.OaNe
publicList getUserByPage(Page page)throws _\[G7
5w9<_W0d
HibernateException; 55\mQ|.Jn
b5R*]
} lY`<-`{I_
VV0$L=mo
l"8YI sir
P!EX;+7+x
G.T1rUh=
java代码: T(DE^E@a
X;tk\Ixd
iI7~9SCE
/*Created on 2005-7-15*/ AJu.
package com.adt.dao.impl; Y}Uw7\e
"N_?yA#(j
import java.util.List; <Z;BB)I&C`
K%;yFEZ
import org.flyware.util.page.Page; d\M
!o*U
Y`uCDfcQ
import net.sf.hibernate.HibernateException; (WvA9s{/
import net.sf.hibernate.Query; #4>F%_
[G*mQ@G9
import com.adt.dao.UserDAO; I4'j_X
t
K#@FKv|("
/** {'%=tJ[YX
* @author Joa ;Lu|fQ#u*
*/ U^D7T|P$V
public class UserDAOImpl extends BaseDAOHibernateImpl M;R>]wP"V
;]!
implements UserDAO { V5+a[`]
3Daq5(fLP
/* (non-Javadoc) 2Z~ofrj
* @see com.adt.dao.UserDAO#getUserByName |a+8-@-Tj
rH,N.H#]
(java.lang.String) b%(0AL
*/ yr?\YKV)I
publicList getUserByName(String name)throws \N30SG?o
syF/jWM5
HibernateException { K9R[
oB]b
String querySentence = "FROM user in class ln5On_Wm
EZ4qhda
com.adt.po.User WHERE user.name=:name"; 4)_ [)MZ\j
Query query = getSession().createQuery E2MpMR
) =[Tgh
(querySentence); uw]Jm"=w
query.setParameter("name", name); Zh@\+1]
return query.list(); sp%7iNs
} Ts\7)6|F
DWAU8>c+
/* (non-Javadoc) IF=rD-x
* @see com.adt.dao.UserDAO#getUserCount() @OpcS>:R
*/ vjpe'zx
publicint getUserCount()throws HibernateException { (ZYOm
int count = 0; hY!G>d{J
String querySentence = "SELECT count(*) FROM !s$fqn
6
3;A1[E6K
user in class com.adt.po.User"; ="`y<J P
Query query = getSession().createQuery -}%zus5
-?uwlpm#
(querySentence); GCrN:+E0FJ
count = ((Integer)query.iterate().next bWqGypq4
*;Vq0a!
()).intValue(); NoMC*",b>
return count; $jHL8r\e7
} sEoS[t|"
HN:{rAIfc
/* (non-Javadoc) ]n{2cPx5d
* @see com.adt.dao.UserDAO#getUserByPage G 6][@q
7cC$)
(org.flyware.util.page.Page) ZrTq)BZ
*/ Z5\6ca
publicList getUserByPage(Page page)throws _u>+H#
L2 I/h`n"
HibernateException { A#T;Gi
String querySentence = "FROM user in class \ .:CL?m#
\1tce`+
com.adt.po.User"; I0Vm^\8
Query query = getSession().createQuery `]%{0 Rx
b`^$2RM&
(querySentence); As"'KR
query.setFirstResult(page.getBeginIndex()) Z8m/8M
.setMaxResults(page.getEveryPage()); r@_;L>
return query.list(); })J]D~!p
} &?~> I[^~
a@%FwfIu
} ]Y3ALQr!
=%a.C(0&G
&P\T{d2"
NWKD:{
~sM334sQ
至此,一个完整的分页程序完成。前台的只需要调用 !XK p_v
+'[iyHBJ
userManager.listUser(page)即可得到一个Page对象和结果集对象 1f}Dza9
cM55
vVd
的综合体,而传入的参数page对象则可以由前台传入,如果用 $Q?UyEi
il:+O08_
webwork,甚至可以直接在配置文件中指定。 9{+B lNZ
f1Rm9``
下面给出一个webwork调用示例: Z
rvb
%
java代码: `/0FXb
8h
wt-)5f'{
C<{k[!N%zm
/*Created on 2005-6-17*/ Jr#ptf"Wu
package com.adt.action.user; |`,%%p|T%
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import java.util.List; r l!c\
,UY],;ib
import org.apache.commons.logging.Log; ?:UDK?
import org.apache.commons.logging.LogFactory; La9dFe-uu{
import org.flyware.util.page.Page; qF>}"m
`?~pk)<C].
import com.adt.bo.Result; ni9/7
import com.adt.service.UserService; ZVeY`o(uE
import com.opensymphony.xwork.Action; =T9QmEBm
,*Sj7qb#
/** ,b2Cl[
* @author Joa y6;A4p>
*/ ao Y"uT+
publicclass ListUser implementsAction{ `NrxoU=
R\)pW9)
privatestaticfinal Log logger = LogFactory.getLog NCBS=L:
)fv0H&g
(ListUser.class); ![ Fb~Egc
4h?[NOA"
private UserService userService; waldLb>7D
(J5E]NV
private Page page; CsXIq.9
&Zd!|u
privateList users; UP^{'eh
e5C560
/* B_nim[72
* (non-Javadoc) mm'Pe4*
* iq=<LOx
* @see com.opensymphony.xwork.Action#execute() ;i> |5tEy
*/ an=8['X
publicString execute()throwsException{ 3
rV)JA
Result result = userService.listUser(page); qf7lQovK
page = result.getPage(); 3Jf_3c
users = result.getContent(); DhYQ>Gv8U
return SUCCESS; ,)|nxX
} Ak^g#^c*
0DV
.1
/** z`y!C3w<
* @return Returns the page. GBVw6+(c
*/ 4DaLmQ2O
public Page getPage(){ FQ26(.
return page; >S,yqKp37~
} Z`Rrv$M!
*shE-w;C
/** HM/2/
/
* @return Returns the users. #41~`vq3
*/ 3dTz$s/[
publicList getUsers(){ ]nY,%XE
return users; 9@/X;zO
} Lk9X>`b#B
Ru9QQaHE
/** YzNSZJPD
* @param page * G!C 'w\$
* The page to set. t2uX+1F
*/ 50q(8F-N
publicvoid setPage(Page page){ Ii FeO
this.page = page; o'O;69D]tX
} 3|x*lmit
DybuLB$f
/** E">FH>8K}
* @param users ^YiGvZJ
* The users to set. R~
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*/ %/iD@2r
publicvoid setUsers(List users){ H\H4AAP5F$
this.users = users; jrk48z
} @K.{o'
8T-/G9u
/** m[n=t5~
* @param userService Pfi|RTX$'*
* The userService to set. :+#$=4
*/ Sy()r 6n
publicvoid setUserService(UserService userService){ )}w2'(!X8
this.userService = userService; $r+_Y/
} 4~<78r5m
} GYH{_Fq
/5M0[C E
R `K1L!`3
-@bOFClE
3ScOJo
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, m-?hHdO
r c++c,=
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 F^4mO|
gi {rqM
么只需要: ^cRAtoa
java代码: cPunMHD
<tUl(q+ty
)O+V ft
<?xml version="1.0"?> !%X~`&9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork !#&`1cYX
At<D36,^"
1.0//EN" "http://www.opensymphony.com/xwork/xwork- xQUskjv/
2o)8 'Lp
1.0.dtd"> h4ozwVA
P*6h$T
<xwork> >:J7u*>$ '
?i{/iH~Sf
<package name="user" extends="webwork- !}lCwV
f/PqkHF
interceptors"> v_|k:l
NI
r"i2
<!-- The default interceptor stack name x`:c0y9uG
%fuV]
--> v`r![QpYf
<default-interceptor-ref jWL%*dJrN
@ /.w%
name="myDefaultWebStack"/> I3qTSX-
0?o<cC1Z
<action name="listUser" y
g:&cIr,
YMn*i<m
class="com.adt.action.user.ListUser"> .QU]
<param 2WK c;?
"|Gr3 sD
name="page.everyPage">10</param> 1K#%mV_
<result ;RK;kdZ
KwHlpW*
name="success">/user/user_list.jsp</result> V_3K((P6
</action> sTS/]"l
5pU/X.lc
</package> 'iWDYZ?
@+{F\SD\
</xwork> %(1Jt"9|
vw6>eT
mY[*(a
p%R+ c
W m&*
'=0l{hv@
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 + )n}n5
qizQt]l
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。 y?V^S;}&]
[sNvCE$\]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 J#gG*(
d#HlO}
Q?V+
0J
G0A\"2U
"$/1.SX;]
我写的一个用于分页的类,用了泛型了,hoho fg7
4,08`5{
java代码: xO^lE@a o
)Ma/]eZ^I
_T_6Yl&cf)
package com.intokr.util; BNgm+1?L
(tyky&$!
import java.util.List; 1Va=.#<
OdpHF~(Y/
/** i&%m^p
* 用于分页的类<br> gFd*\Dk
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 9}_'
* t3AmXx
* @version 0.01 UxxX8N
* @author cheng UhJ{MUH`
*/ gA`QV''/:
public class Paginator<E> { AB{zkEuK
privateint count = 0; // 总记录数 {1_<\~J
privateint p = 1; // 页编号 +/bD9x1H
privateint num = 20; // 每页的记录数 q6ZewuV.
privateList<E> results = null; // 结果 uq/Fapl
PCHKH
/** $o0.oY#
* 结果总数 ~%2yDhdQ
*/ lMH~J8U3
publicint getCount(){ w+r).PS}C
return count; za+)2/
`L
} dVk(R9 8
V;W{pd-I
publicvoid setCount(int count){ OwEu S#-
this.count = count; 6i%6u=um3
} `x=$n5=8
q(X7e
/** as'yYn8
* 本结果所在的页码,从1开始 )&O6d .
* mP=[h
|a$r
* @return Returns the pageNo. rB{w4
*/ rHM^_sYRb
publicint getP(){ |N^"?bSt
return p; AloL+eN@
} *u:,@io7'G
q7<d|s
/** "GR*d{
* if(p<=0) p=1 }O>4XFj
* W9pY=9]p+
* @param p IuT)?S7O*k
*/ / Y od
publicvoid setP(int p){ _5H~1G%q
if(p <= 0) x=IZ0@p
p = 1; l
S3LX
this.p = p; 6^t#sEff]
} 7y&6q`y E
G0|}s&$yL
/** w/O'&],x
* 每页记录数量 N$=9R
*/ Y<u%J#'[
publicint getNum(){ BWQ`8
return num; h=,hYz?]
} 4].o:d;`/
K#N9N@W jR
/** /8Y8-&K0
* if(num<1) num=1 CQNMCYjg(R
*/ V8):!
publicvoid setNum(int num){ K!Fem6R
if(num < 1) 38T]qz[Sn
num = 1; u<uc"KY=
this.num = num; jrFPd
} ~?Vo d|>
;4ybkOD
/** P8}IDQ9
* 获得总页数 #h^nvRmON
*/ Tx~w(A4:
publicint getPageNum(){ Uz_p-J0
return(count - 1) / num + 1; @IsUY(Gu
} D4@?>ek6U
T0")Ryu
/** ;l_b.z0^6
* 获得本页的开始编号,为 (p-1)*num+1 9#9bm
*/ =DfI^$Lr:
publicint getStart(){ |9%~z0
return(p - 1) * num + 1; Nwt[)\W `
} |f @A-d X
LwRzzgt
/** Pe,k y>ow
* @return Returns the results. 8^+|I,
*/ MymsDdQ]
publicList<E> getResults(){ 3))CD,|
return results; }dzVwP=
} &hkD"GGe
e-P{)L<s5
public void setResults(List<E> results){ gEsD7]o(=
this.results = results;
..E_M$}
} >QvqH 2
L!l?tM o
public String toString(){ Yg '(
StringBuilder buff = new StringBuilder t2{(ETV
/klo),|&
(); 'l<$H=ZUVG
buff.append("{"); VnSO>O
buff.append("count:").append(count); BM:p)%Pv#P
buff.append(",p:").append(p); 53:u6bb;
buff.append(",nump:").append(num); g]HWaFjc5
buff.append(",results:").append ,"`3N2!Y}
#&IrCq+
(results); %A~. NNbS
buff.append("}"); _ps4-<ugC
return buff.toString(); 5)S;R,
} @w= =*.x
"?6*W"N9
} ~s4JGV~R
.Qn#wub
ufR>*)_+