Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3di;lzGq
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.#Q
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f$kbb6juL
n8=Dzv0
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 8IQ}%|lN
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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 4K~=l%l
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。 `PL}8ydZ
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分页支持类: zPqJeYK
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java代码: SO(BkxV@
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package com.javaeye.common.util; ?
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import java.util.List; U&u6356
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publicclass PaginationSupport { T1.U (::
<nD@4J-A0
publicfinalstaticint PAGESIZE = 30; zEtsMU
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privateint pageSize = PAGESIZE; {}k3nJfE
k?&GL!?
privateList items; {.AN4
;hO6 p
privateint totalCount; _.V5-iN
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privateint[] indexes = newint[0]; ;<Hk Cd
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privateint startIndex = 0; 6)*fr'P
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public PaginationSupport(List items, int k)*apc\W
=Q<7[
totalCount){ kBcTXl
setPageSize(PAGESIZE); ]bh%pn
setTotalCount(totalCount); cl`Wl/Q#
setItems(items); i]?
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setStartIndex(0); 5;" $X 1{
} E~fb#6
WA43}CyAe
public PaginationSupport(List items, int TmLCmy!
(1^;l;7H
totalCount, int startIndex){ 6Yodx$
setPageSize(PAGESIZE); 4jTO:aPh_
setTotalCount(totalCount); y-nv#Ejr
setItems(items); SF+L-R<e
setStartIndex(startIndex); Q~Mkf&s
} [O&}Qk
2p](`Y`
public PaginationSupport(List items, int S%}G 8Ty
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totalCount, int pageSize, int startIndex){ Q\kWQOB_
setPageSize(pageSize); 6wWhM&Wd
setTotalCount(totalCount); YlbX_h2S"
setItems(items); 9GCK3
setStartIndex(startIndex); C 4C/
} ^U5N!"6R
i56Rdb
publicList getItems(){ FsWp>}o
return items; WVpx
} G6a 2]
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publicvoid setItems(List items){ c(
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this.items = items; !"qT2<A
} [niFJIsc
_3 oo%?}
publicint getPageSize(){ VED~v#.c
return pageSize; T\.(e*hC
} QCZ88\jX[
GLecBF+>F
publicvoid setPageSize(int pageSize){ a'jUM+D;
this.pageSize = pageSize; TY %zw6 #p
} lkTA"8d
iv +a5
publicint getTotalCount(){ g_c@Kyf
return totalCount; 77[TqRLf
} ;k `51=Wi
u3O@ccJ;
publicvoid setTotalCount(int totalCount){ KqJln)7
if(totalCount > 0){ Lr:n
this.totalCount = totalCount; -+1O*L!
int count = totalCount / 0~RD@>]
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pageSize; \&kj#)JYA
if(totalCount % pageSize > 0) M KW~rrR
count++; WFahb3kx
indexes = newint[count]; yXDjM2oR/2
for(int i = 0; i < count; i++){ *|W](id7e
indexes = pageSize * WJONk_WAc
Bh=t%#y|`
i; W7uX
} 5U7,,oyh
}else{ :stHc,
this.totalCount = 0; /mz.HCs
} Ro9:kEG$
} ;y\/7E
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publicint[] getIndexes(){ |=YK2};
return indexes; U&])ow):
} !;&\n3-W
hGV_K" ~I0
publicvoid setIndexes(int[] indexes){ +W[f>3`VQ
this.indexes = indexes; K1J |\!o
} <lIm==U<-
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publicint getStartIndex(){ "Tser*i )
return startIndex; `K+%/|!
} }hg=#*
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publicvoid setStartIndex(int startIndex){ D8,8j;
if(totalCount <= 0) V;SV0~&
this.startIndex = 0; [XI:Yf
elseif(startIndex >= totalCount) bi+M28m
this.startIndex = indexes aQL0Sj:,
8Snv, Lb`^
[indexes.length - 1]; A+Isk{d
elseif(startIndex < 0) td%J.&K_*'
this.startIndex = 0; RRS)7fFm
else{ D`^wj FF
this.startIndex = indexes M&/4SVBF
Q]TZyk
[startIndex / pageSize]; tKUW
} | 8mWR=9fs
} akr2Os
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publicint getNextIndex(){ WcSvw
int nextIndex = getStartIndex() + Nm&'&L%Ch
R7(XDX=[s
pageSize; &PV%=/-J
if(nextIndex >= totalCount) "$(D7yFO
return getStartIndex(); ej_u):G*
else #KoI8U"
return nextIndex; |g}r
} 8*/;W&7y
]>[TF'pIAx
publicint getPreviousIndex(){ 0'F/z%SMj
int previousIndex = getStartIndex() - vS~tr sI
z{ eZsh
b
pageSize; jSvq1$U
if(previousIndex < 0) f:\)!
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return0; $*X?]?
else DjK7_'7(L
return previousIndex; :l]qTCmY
} &1T)'Bn
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} ?Ybq]J\q
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YC6guy>
抽象业务类 T;B FO5G@
java代码: TC<Rg?&yb
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/** d:>^]5cE&
* Created on 2005-7-12 U5j4iz'
*/ bnkZWw'9
package com.javaeye.common.business; )=gU~UV
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import java.io.Serializable; 7{M&9| aK
import java.util.List; O,
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import org.hibernate.Criteria; [[T6X9
import org.hibernate.HibernateException; kdGq\k,
import org.hibernate.Session; ^C~_}/cZ
import org.hibernate.criterion.DetachedCriteria; .9ZK@xM&?
import org.hibernate.criterion.Projections; 'vtJl
import c0e[vrP:
V0A> +
org.springframework.orm.hibernate3.HibernateCallback;
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import 1mtYap4
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org.springframework.orm.hibernate3.support.HibernateDaoS B2$cY;LH
sM)1w-
upport; qY%|Uo
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import com.javaeye.common.util.PaginationSupport; P4yUm(@
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public abstract class AbstractManager extends $s1/Rmw
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HibernateDaoSupport { q,7W,<-
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privateboolean cacheQueries = false; 1O0)+9T82
Q'=7#_
privateString queryCacheRegion; gp$]0~[tO
1(T2:N(M-A
publicvoid setCacheQueries(boolean a,4GE'
3
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cacheQueries){ {7oPDP
this.cacheQueries = cacheQueries; o8:9Yjs
} #w5%^HwO
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publicvoid setQueryCacheRegion(String ?m5"|f\
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queryCacheRegion){
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this.queryCacheRegion = 4w9=z,
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queryCacheRegion; ,f)+|?wz
} O\cc=7
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publicvoid save(finalObject entity){ 32 j){[PL3
getHibernateTemplate().save(entity); U:7w8$_
} ;s$4/b/~
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publicvoid persist(finalObject entity){ O251. hXK
getHibernateTemplate().save(entity); Sru0j/|H\
} *^{j!U37s
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publicvoid update(finalObject entity){ fO5L[U^`
getHibernateTemplate().update(entity); ( -q0!]E
} $tW E9_
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publicvoid delete(finalObject entity){ \rh+\9(
getHibernateTemplate().delete(entity); tkptm%I_
} C[TjcHoA
c^H#[<6p
publicObject load(finalClass entity, f:P;_/cJc
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finalSerializable id){ v h)CB8
return getHibernateTemplate().load $_'<kH-eP
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(entity, id); ->{\7|^
} #%$@[4"V
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publicObject get(finalClass entity, (aJ$1bT=T
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finalSerializable id){ # ^,8JRA
return getHibernateTemplate().get /8:e|
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(entity, id); Sa)L=5Nr
} Z{%W!>0
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publicList findAll(finalClass entity){ e$QMR.'
return getHibernateTemplate().find("from _(=g[=Mer
H 9BqE+
" + entity.getName()); t vW0 W
} \jZmu
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publicList findByNamedQuery(finalString BUi,+NdIk
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namedQuery){ TL"+Iv2]/$
return getHibernateTemplate #NMQN*J>D
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().findByNamedQuery(namedQuery); X}={:T+6s
} `;R$Ji=>
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publicList findByNamedQuery(finalString query, {9P(U\]e]k
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finalObject parameter){ iSX:H;
return getHibernateTemplate ZV5IZ&V!
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().findByNamedQuery(query, parameter); 1 Cz}|#U
} eUu<q/FUMj
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publicList findByNamedQuery(finalString query, d{WOO)j
.}!.:
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finalObject[] parameters){ 3h o'\Ysu/
return getHibernateTemplate .VmRk9Z
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().findByNamedQuery(query, parameters); 9}K
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} 9w0v?%%_
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publicList find(finalString query){ 3WGOftLzt
return getHibernateTemplate().find f@Ve,i
gm:Y@6W
(query); NN:zQ_RT
} 2=7[r-*E
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publicList find(finalString query, finalObject \:JY[s/
"K|':3n|
parameter){ Bbb":c6w0
return getHibernateTemplate().find :$X dR:f}}
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(query, parameter); \\oa[nvL~
} _S &6XNV
fpzEh}:H\
public PaginationSupport findPageByCriteria (YPG4:[
4eaH.&&
(final DetachedCriteria detachedCriteria){ PCBV6Y7r
return findPageByCriteria aiw4J
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); PUd/|Rc/}
} C}o^p"M*B3
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public PaginationSupport findPageByCriteria
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.b2%n;_>.
(final DetachedCriteria detachedCriteria, finalint 'Ze&
LQ
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startIndex){ [H`5mY@
return findPageByCriteria ${t$:0R,h
fB4zqMSfE
(detachedCriteria, PaginationSupport.PAGESIZE, _Mh..#)`[
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startIndex); uE#i3(
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} 8rz,MsFR
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public PaginationSupport findPageByCriteria D/2;b;-
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(final DetachedCriteria detachedCriteria, finalint yzGBGC
7B)@ aUj$
pageSize, d5W=?
finalint startIndex){ b%j4W)Z
return(PaginationSupport) uy=<n5`oNG
#D+.z)iZn
getHibernateTemplate().execute(new HibernateCallback(){ ?/Aql_?3
publicObject doInHibernate Dx P65wU
$*9:a3>zny
(Session session)throws HibernateException { K}LF ${bS
Criteria criteria = . Eb=KG
cgQ2Wo7tCq
detachedCriteria.getExecutableCriteria(session); Q#4OgNt
int totalCount = qyBo|AQ5
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((Integer) criteria.setProjection(Projections.rowCount w*4sT+
P
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()).uniqueResult()).intValue(); 3KKq1][
criteria.setProjection &e4EZ
AeW_W0j
(null); Q(hAV
List items = <$nMqUu0
lYrW"(2
criteria.setFirstResult(startIndex).setMaxResults [lj^lN8
lR]SGdY
(pageSize).list(); hl+
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PaginationSupport ps = 1~*JenV-
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new PaginationSupport(items, totalCount, pageSize, dM5N1$1,
QnH~'
k
startIndex); I9cZZ`vs
return ps; 8{-bG8L> 5
} B o[aiT
}, true); G4f%=Z
} [sG!|@r
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public List findAllByCriteria(final *C^`+*}OE$
k/%n7 ;1
DetachedCriteria detachedCriteria){ OFw93UJ Y
return(List) getHibernateTemplate YYd!/@|N5
Rd+`b
().execute(new HibernateCallback(){ >!P !F(
publicObject doInHibernate
] 2lhJ
myWa>Mvb
(Session session)throws HibernateException { :YN,cI d*
Criteria criteria = %R*-oQ1T
yLCJSN$7
detachedCriteria.getExecutableCriteria(session); 9jt+PII
return criteria.list(); =MMSmu5!
} <o_(,,P%
}, true); :#spL*FIx
} h@(S];.
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public int getCountByCriteria(final K2pW|@~U
?(j:F2dU~
DetachedCriteria detachedCriteria){ h-RL`X
Integer count = (Integer) | <l=i(
R;2
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getHibernateTemplate().execute(new HibernateCallback(){ M!b"c4|<
publicObject doInHibernate sJ)Pj?"\?
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(Session session)throws HibernateException { Ba]^0Y
u
Criteria criteria = [5Pin>]z
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detachedCriteria.getExecutableCriteria(session); ."JtR
return co%-d
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criteria.setProjection(Projections.rowCount +d,Z_ 6F
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()).uniqueResult(); l)(
3]
} A<s9c=d6
}, true); qCgoB 0
return count.intValue(); SpX6PwM
} '#@tovr
} qFYM2
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用户在web层构造查询条件detachedCriteria,和可选的 Eh&HN-&
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 I Z{DR
l^E)XWd
PaginationSupport的实例ps。 Omy<Y@$
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ps.getItems()得到已分页好的结果集 E(G&mfhb
ps.getIndexes()得到分页索引的数组 $fl+l5?9
ps.getTotalCount()得到总结果数 eUE(vn#
ps.getStartIndex()当前分页索引 '?MT"G
ps.getNextIndex()下一页索引 $^j#z^7
ps.getPreviousIndex()上一页索引 /L? ia
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ae|j#!~oi
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1=Nh<FuQ
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ct![eWsuB
~zT7 43
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 R\d)kcy4
IG=# 2 /$
一下代码重构了。 TQg~I/
% #$K P
我把原本我的做法也提供出来供大家讨论吧: }MXC0Z~si
A
2Rp
首先,为了实现分页查询,我封装了一个Page类: X(*MHBd
java代码: .-HwT3
- HiRXB
8Xjp5
/*Created on 2005-4-14*/ 2\J-7o=P
package org.flyware.util.page; $|%BaEyk
r>ca17
/** <P1yA>=3`
* @author Joa :M
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* 8%Hc%T[RnT
*/ lLi)?
publicclass Page { K)[DA*W
%{HeXe
/** imply if the page has previous page */ p]erk
privateboolean hasPrePage; ]
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/** imply if the page has next page */ WYXh1_nyk
privateboolean hasNextPage; '| rhm
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/** the number of every page */
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privateint everyPage; e'0BP,\f_}
|Pj]sh[^Y
/** the total page number */ AD^Q`7K?uR
privateint totalPage; !$L~/<&0g
)LDBvpJyQ
/** the number of current page */ 5Sv;a(}
privateint currentPage; JsD|igqF-
AMf{E
/** the begin index of the records by the current Z(:q.{"r
{k8R6l1
query */ ~D\zz }l
privateint beginIndex; VBv|7S
oo2CF!Xy
<<l1zEf@
/** The default constructor */ YgL{*XYAt
public Page(){ BOdd~f%&tn
OD;F{Hc
} {DWL 5V#M
[Lal_}m?
/** construct the page by everyPage 33z^Q`MTC
* @param everyPage IB\O[R$x
* */ }NpN<C+
public Page(int everyPage){ wlsq[xP
this.everyPage = everyPage; My<.^~
} 2D)B%nM[
'B yB1NL
/** The whole constructor */ It:,8
public Page(boolean hasPrePage, boolean hasNextPage, 6%L#FSI
!j%MN{#a
:`>bh
int everyPage, int totalPage, {j[a'Gb
int currentPage, int beginIndex){ JBk >|q"
this.hasPrePage = hasPrePage; ^aR^M\38
this.hasNextPage = hasNextPage; []b=
xRJM
this.everyPage = everyPage; SQs+4YJ
this.totalPage = totalPage; n4InZ!)
this.currentPage = currentPage; ^ DCBL&I
this.beginIndex = beginIndex; x|`BF%e/v
} t0.71(
_Nacqa
/** Lq2ZgKd!
* @return >0E3Em<(}l
* Returns the beginIndex. _|VF^\i
*/ s
a{x.2/o}
publicint getBeginIndex(){ <N{Y*,^z
return beginIndex; }?^]-`b
} d}Xb8SaE%c
,{2= nb[
/** -an~&C5\
* @param beginIndex
!U=o<)I
* The beginIndex to set. l/-qVAd!q
*/ wQX18aF/#d
publicvoid setBeginIndex(int beginIndex){ ~CuJ$(9Y
this.beginIndex = beginIndex; R4vf
} O;+
sAt
L(o#)I>j
/** Ubm]V{7
* @return COA*Q
* Returns the currentPage. Qv6-,6<
*/ P:%r3F
publicint getCurrentPage(){ 7sq15oL
return currentPage; z-N
N(G+
} >!MRk[@
V-
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/** EGVS8YP>h
* @param currentPage LK+67Y{25
* The currentPage to set. @{{6Nd5
*/ >S>B tRl
publicvoid setCurrentPage(int currentPage){ tUi@'%>=5
this.currentPage = currentPage; ZRj/lQ2D
} ^cCNQS}r
S$ n?
/** m:6*4_!
* @return \+j:d9?
* Returns the everyPage. ),J6:O&
*/ `Wd4d2aLG
publicint getEveryPage(){ '*D>/hn|:]
return everyPage; |j=Pj)5J
} S!66t?vHB
EV@yJ]
/** I,W`s
* @param everyPage dkg|
kw'
* The everyPage to set. uCoy~kt292
*/ ny:/a
publicvoid setEveryPage(int everyPage){ RTr"#[
this.everyPage = everyPage; XhUVDmeUMb
} XtqhK"f%
,\T7{=ZG\!
/** A1n4R
* @return _+,>NJ
* Returns the hasNextPage. i0F6eqe=J
*/ Qs ysy
publicboolean getHasNextPage(){ t;V^OGflv
return hasNextPage; L7[f-cK2:
} OXnTD!m>{
m-bu{
/** }W0_eQ
* @param hasNextPage NMS+'GRW
* The hasNextPage to set. YC(X=
D
*/ wxJoWbn
publicvoid setHasNextPage(boolean hasNextPage){ kB.CeG]tk
this.hasNextPage = hasNextPage; 2!R+5^Iy
} PD~vq^@Q
s|I$c;>
/** CEAmb[h
* @return vNju|=Lo
* Returns the hasPrePage. 9_O6Sl
*/ tz5\O}
publicboolean getHasPrePage(){ a7!{`fR5
return hasPrePage; L;WFHIE
} 0BH-kr
(/FG#D.
/** ]=PkgOJD
* @param hasPrePage dQ_hlx!J
* The hasPrePage to set. (|>rDk;
*/ -A@/cS%p
publicvoid setHasPrePage(boolean hasPrePage){ l6zYiM
this.hasPrePage = hasPrePage; 1Tr%lO5?6
} =RAojoN
^B1$|C
D,
/** >pp#>{}
* @return Returns the totalPage. aW}d=y[
* @_wJN Qo`
*/ s
bd$.6
|&
publicint getTotalPage(){ djqw5kO:R
return totalPage; |*^}e54
} 'uF75C
B<ue}t
/** > `mV^QD
* @param totalPage %=$Knc_!T^
* The totalPage to set. yy+:x/(N[
*/ &*745,e
publicvoid setTotalPage(int totalPage){ ZL:SJ,C
this.totalPage = totalPage; 6AoKuT;
} IJVzF1vC
[] el4.J,
} lF
t^dl^
?C- ju8]|
U1(cBY
v!$:t<-5N
mT #A?C2
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 E]}_hZU
t1G__5wp
个PageUtil,负责对Page对象进行构造: 0wCQPvO
java代码: |3^U\r^zo
r-*j"1 e
N.0g%0A.D
/*Created on 2005-4-14*/ =dsEt\
j
package org.flyware.util.page; [%O f
pRzL}-[/v
import org.apache.commons.logging.Log; `<kB/T
import org.apache.commons.logging.LogFactory; O8cZl1C3
hiEYIx
/** ns*:mGh
* @author Joa #SG.`J<%
* dS\!tdHP-Q
*/ -2(?O`tZ
publicclass PageUtil { IMBjI#\
R1/c@HQw?
privatestaticfinal Log logger = LogFactory.getLog =XK}eQ_d
|KY-kRN7
(PageUtil.class); uGF{0)0g
t2YB(6w+xg
/** gVe]?Jva`
* Use the origin page to create a new page E-($Xc
* @param page T
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* @param totalRecords wph8ln"C-
* @return ;mRZ_^V;
*/ oe|8
publicstatic Page createPage(Page page, int $7W5smW/
[$pb
totalRecords){ jD%|@ux
return createPage(page.getEveryPage(), \<\H1;=.@'
&]GR*a
page.getCurrentPage(), totalRecords); *X{7m]5
} IsShAi
TZ `Ypi7r
/** h"/'H)G7_&
* the basic page utils not including exception
2W`WOBz
Xs# _AX
handler JWYe~
* @param everyPage cy)-Rfg
* @param currentPage ![nL/
* @param totalRecords S;jD@j\t&
* @return page ecQ{ePoU
*/ r
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publicstatic Page createPage(int everyPage, int g{i= $xc
5IOGH*'U8
currentPage, int totalRecords){ em5~4;&'
everyPage = getEveryPage(everyPage); e&*b{>1*
currentPage = getCurrentPage(currentPage); dJ#go*Gn
int beginIndex = getBeginIndex(everyPage, wy
.96
^<;CIXo
currentPage); EpQy;#=;
int totalPage = getTotalPage(everyPage, aSu^
LnKgT1
totalRecords); Aj=GekX{
boolean hasNextPage = hasNextPage(currentPage, 1KbZ6Msy
S,ea[$_
totalPage); /}J_2
boolean hasPrePage = hasPrePage(currentPage); qp/1tC`
L6DYunh}^N
returnnew Page(hasPrePage, hasNextPage, _hJdC|/
everyPage, totalPage, 9P)!v.,T/
currentPage, g1}:;VG=
*S"RU~1_
beginIndex); dP(.l}O
} /d,u"_=l
~*"ZF-c,
privatestaticint getEveryPage(int everyPage){ C:}1r
return everyPage == 0 ? 10 : everyPage; T/2k2r4PD
} B@NBN&Fr
}(
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privatestaticint getCurrentPage(int currentPage){ HfgTc
h
return currentPage == 0 ? 1 : currentPage; &VA^LS@b
} ~CbiKez
^<-)rzTI
privatestaticint getBeginIndex(int everyPage, int %OB>FY:|
IW&*3I<K
currentPage){ >
Xh=P%
return(currentPage - 1) * everyPage; jex\5
} !=PH5jTY
@TD=or .&
privatestaticint getTotalPage(int everyPage, int O39
s~2o<#
totalRecords){ 7<*0fy5n n
int totalPage = 0; _z8"r&
VFx[{Hy
if(totalRecords % everyPage == 0) li
v=q
totalPage = totalRecords / everyPage; CHZ/@gc
else <5}I6R;
totalPage = totalRecords / everyPage + 1 ; ygj%VG
U~)5 {
return totalPage; Xwdcy J!
} i&^JG/a
T4Vp0i
privatestaticboolean hasPrePage(int currentPage){ ]'[:QGr
return currentPage == 1 ? false : true; Z37Dv;&ZD
} - _8-i1?
|LZ{kD|
privatestaticboolean hasNextPage(int currentPage, iu(obmh/o
>r7PK45.K
int totalPage){ ?d%{-
return currentPage == totalPage || totalPage == =X^a
_u^3uzu
0 ? false : true; m"/..&'GC
} gaz",kK<
:Ae#+([V
`^[Tu 1
} {<@ud0A:\
.\T!oSb4[
W_E^+Wl@
v]EZYEXFL)
$Wj{B@k
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 F~fBr
T9&{s-3*
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 }T(=tfv@
~!~i_L\V
做法如下: u&uFXOc'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 &g&,~Y/z;
JygJ4RI%j
的信息,和一个结果集List: {l!{b1KJ
java代码: h)ZqZ'k$
jT$J~MpHh
6xtgnl#T
/*Created on 2005-6-13*/ uA[
:
package com.adt.bo; TP {\V>*Yz
CEkUXsp
import java.util.List; RV_I&HD!
2(0%{*m
import org.flyware.util.page.Page; 1E
/G+pm
qpjZ-[UC
/** (}6\_k[}m
* @author Joa MnqT?Cc4$j
*/ _q#pEv
publicclass Result { EjFpQ|-L|
Vm\zLWNB
private Page page; ukEJ D3i
;lb
private List content; PNo:[9`S;m
=E]tEi
/** $;G<!]& s
* The default constructor He'VqUw_
*/ 5NUaXQ
public Result(){
l$\B>u,>
super(); N,rd= m+
} J-'XT_k:iM
J/K~8sc
/** Q"u2<
* The constructor using fields =|aZNHqH
* `<d.I%}
* @param page G^nG^HTo5
* @param content ^gx~{9`RR
*/ xBc|rqge
public Result(Page page, List content){ -O?HfQ
this.page = page; CF','gPnc
this.content = content; N8At N\e
} IMbF]6%p(
5o 5DG
/**
=cS5f#0
* @return Returns the content. JD0s0>q_
*/ aV|VC$
publicList getContent(){ $Ugc:L<h+
return content; 467"pqT
} UakVmVN/P
C=r`\W
/** )#i"hnYpQ
* @return Returns the page. Y%
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*/ beikzuC
public Page getPage(){ H!7?#tRU
return page; zn^7#$fC
} 7L&,Na
0]*W0#{Zj
/** [<U=)!Swg
* @param content y
`FZ 0FI
* The content to set. Q njK<}M9
*/ T^#d;A
public void setContent(List content){ *5oQZ".vA*
this.content = content; $dKfUlO
} ww7nQ}H5(
i0wBZ i?
/** iOEBjj;C
* @param page :3R3>o6m
* The page to set. a@jM%VZ
*/ OET/4(C
publicvoid setPage(Page page){ ~D}fy
this.page = page; C}<e3BXc
} D=z="p\
} ]!sCWR
$mKExW
]!^wB 3j
"@^<~bw
-Q J8\/1>
2. 编写业务逻辑接口,并实现它(UserManager, j*|0#q;e6
Mx6
yk,
UserManagerImpl) =|Qxv`S1
java代码: BaI-ve
oKGF'y?A>
Ru#pJb(R
/*Created on 2005-7-15*/ Ih.)iTs~%
package com.adt.service; bcwb'D\a
c-&Q_lB
import net.sf.hibernate.HibernateException; W&cs&>F#
$eT[`r
import org.flyware.util.page.Page; ./3/3&6
(?'vT%
import com.adt.bo.Result; (_FeX22+
RAu(FJ
/** 6(7{|iY
* @author Joa Q~ Ad{yC
*/ z.RM85 ?T
publicinterface UserManager { -a>CF^tH
LNR1YC1c
public Result listUser(Page page)throws k)D5>T
`a[fC9
HibernateException; %7`eT^
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} ~"\v(\P e
Q'3tDc<
Z]{=Jy!F
mDp8JNJNE
U&
java代码: ._j?1Fw`
|P&
\C8h
G#`
/*Created on 2005-7-15*/ fW=<bf
package com.adt.service.impl; >)NS U
'L7u`
import java.util.List; @N<h`vDa
dQrz+_
import net.sf.hibernate.HibernateException; .
4RU'9M
NpM;vO
import org.flyware.util.page.Page; tMP"9JE,
import org.flyware.util.page.PageUtil; Oh10X.)i
-&1P2m/46
import com.adt.bo.Result; wsQuJrG
import com.adt.dao.UserDAO; x|d? '
import com.adt.exception.ObjectNotFoundException; (U$;0`
import com.adt.service.UserManager; /%7&De6Xg
7D>_<)%d=
/** 95j`^M)Q
* @author Joa Tr}XG
*/ ep},~tPZn
publicclass UserManagerImpl implements UserManager { V8WSJ=-&
B0Z>di:
private UserDAO userDAO; wE<r'
[+W<;iep
/** X-"
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* @param userDAO The userDAO to set. #/H2p`5
*/ ~;]zEq-hG
publicvoid setUserDAO(UserDAO userDAO){ TUwX4X6m
this.userDAO = userDAO; N8kNi4$mp=
} V'dw=W17V
2/A*\
/* (non-Javadoc) 9* 3;v;F
* @see com.adt.service.UserManager#listUser -~JYfj@
cVMRSp
(org.flyware.util.page.Page) HrZX~JnTmf
*/ SvkCx>6/G
public Result listUser(Page page)throws nIL67&
B:UM2Jl
HibernateException, ObjectNotFoundException { KlS#f
int totalRecords = userDAO.getUserCount(); GB}=
if(totalRecords == 0) dP_bFU zg
throw new ObjectNotFoundException sz/^Ie-~
W?wt$'
("userNotExist"); 8_Uhh5[
page = PageUtil.createPage(page, totalRecords); m:0[as=
List users = userDAO.getUserByPage(page); 3'i(wI~<[
returnnew Result(page, users); %LmsywPPp
} \JR^uJ{Y
(dyY@={q
}
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OXKV6r6f
d)Z&_v<|
o+XQMg
+rSU
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 OR
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ue+{djz[4
询,接下来编写UserDAO的代码: z>y#^f)r
3. UserDAO 和 UserDAOImpl: #l- 0$
java代码: 0J466H_d{
S#y GqN0i
a%kvC#B
/*Created on 2005-7-15*/ h* 1T3U$
package com.adt.dao; Np$&8v+en
o-l-Z|)7
import java.util.List; FZ]+(Q"]:
YXqYIG.G
import org.flyware.util.page.Page; ,=G]tnsv^
dcq18~
import net.sf.hibernate.HibernateException; :06.b:_
/|H9Gm
/** 3 4%B0
* @author Joa uH'? Ikx"
*/ 8L_OH
publicinterface UserDAO extends BaseDAO { S|@/"?DC
N`?/kubD
publicList getUserByName(String name)throws 0T(+z)Ki
id8QagJ
HibernateException; 3< 6h~ek)
6:; >id${
publicint getUserCount()throws HibernateException; LCj3{>{/=
/5L\:eX%
publicList getUserByPage(Page page)throws ?mK&Slh.
3pW4Ul@e
HibernateException; H-u
SdT
d2gYBqag
} rMjb,2*rC7
kF,ME5%
/)K;XtcN
j%bC9UkE3
|7A}LA
java代码: {=Jo!t;f
yk5K8D[tV
< Mu`,Kv*
/*Created on 2005-7-15*/ ;Sg.E8
package com.adt.dao.impl; m0h,!
52#6uBe
import java.util.List; m2l9([u=^
)wD/<7;
import org.flyware.util.page.Page; _
gYj@
%
_Ds,91<muQ
import net.sf.hibernate.HibernateException; y`7<c5zD
import net.sf.hibernate.Query; 6dz^%Ub
W1)<!nwA
import com.adt.dao.UserDAO; W+"^! p|
0MxK+8\y
/** SVd@-
'-K
* @author Joa >35w"a7S
*/ _$D!"z7i
public class UserDAOImpl extends BaseDAOHibernateImpl h.ftl2>
}KIS_krs
implements UserDAO { ,tyPZR_
@^-Y&N!b=
/* (non-Javadoc) (/]#G8
* @see com.adt.dao.UserDAO#getUserByName CP%^)LX *
4~FRE)8
(java.lang.String) $2i@@#g8
*/ L'aB/5_%
publicList getUserByName(String name)throws hp9LV2_5
7(tsmP
HibernateException { S|LY U!IWZ
String querySentence = "FROM user in class $^?VyHXvY
p19@to5l
com.adt.po.User WHERE user.name=:name"; TKsP#Dt/
Query query = getSession().createQuery 1>L'F8"
#Y'b?&b
(querySentence); ^QJJ2 jZ
query.setParameter("name", name); [v*q%Mi_
return query.list(); !|u?z%
} R@tEC)Zn
;A7JX:*?y=
/* (non-Javadoc) xypgG;`\
* @see com.adt.dao.UserDAO#getUserCount() NqOX);'L0
*/ a9{NAyl<oo
publicint getUserCount()throws HibernateException { oxL<\4)WJ
int count = 0; dc1Zh
W4
String querySentence = "SELECT count(*) FROM g<0K
i^#
J!5b~8`v
user in class com.adt.po.User"; .7b%7dQ<\
Query query = getSession().createQuery N_iy4W(NU
5<v1v&
(querySentence); ^5TVm>F@3
count = ((Integer)query.iterate().next q
jc4IW t~
Cfd* Q
()).intValue(); ivq(eKy
return count; 6z6\xkr
} pXN'vP
?H@<8Ra=3
/* (non-Javadoc) s9nPxC&A
* @see com.adt.dao.UserDAO#getUserByPage p!uB8F
{R@V
(org.flyware.util.page.Page) Lkx~>U
*/ )&>W/56/
publicList getUserByPage(Page page)throws YMK ![ q-
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HibernateException { @,k5T51m
String querySentence = "FROM user in class b$#b+G{y
we^'R}d
com.adt.po.User"; 5BXku=M
Query query = getSession().createQuery t ;h`nH[
"zd_eC5
(querySentence); {en'8kS
query.setFirstResult(page.getBeginIndex()) HSROgBNI:
.setMaxResults(page.getEveryPage()); HNBmq>XDc
return query.list(); &b5(Su
} a oU"
W~D_+[P|_
} u|Mx}
+D]raU
0D@ $
v7./u4S|V
LFHJj-nk
至此,一个完整的分页程序完成。前台的只需要调用 ?-mOAHW0q
6V JudNA
userManager.listUser(page)即可得到一个Page对象和结果集对象 MSvZ3[5Io
s*yl&El/
的综合体,而传入的参数page对象则可以由前台传入,如果用 +#BOWz
^ `Ozw^~
webwork,甚至可以直接在配置文件中指定。 t&{;6MiE
,
%z HykP
下面给出一个webwork调用示例: sV%DX5@
java代码: -#;xfJE
Z*mbhod
&Q?@VNi
/*Created on 2005-6-17*/ 4l%W]'
package com.adt.action.user; Hh=fv~X
|> ]@w\]
import java.util.List; Wmcd{MOS
EC,`t*<
import org.apache.commons.logging.Log; MU
a[}?
import org.apache.commons.logging.LogFactory; QE[<Y3M
import org.flyware.util.page.Page; TMPk)N1Ka
<Jhd%O
import com.adt.bo.Result; c5WMN.z
import com.adt.service.UserService; pl&nr7\
import com.opensymphony.xwork.Action; ur'<8pDb$
Jk\-e`eE
/** #d\&6'O
* @author Joa S5 q1Mn
*/ lRg?||1ik
publicclass ListUser implementsAction{ s)qrlv5H
jmr
.gW
privatestaticfinal Log logger = LogFactory.getLog .UL2(0
>iOf3I-ATt
(ListUser.class); <nbklo
A3_p*n@
private UserService userService; s~ 8g
2Wluc37
private Page page; Vl5>o$G|<.
70 R6:
privateList users; ; o_0~l=-/
Hm'"I!jyO
/* %w65)BFQ
* (non-Javadoc) L>sLb(2\i
* nI6ompTX
* @see com.opensymphony.xwork.Action#execute() !mUJ["#
*/ ^)>( <6
publicString execute()throwsException{ PtW2S 1?j
Result result = userService.listUser(page); m#RJRuZ|2V
page = result.getPage(); gUx}vE-
users = result.getContent(); (Fzy8
s
return SUCCESS; 96V8R<
} aH_c84DS
lY
tt|J
/** ^{MqJ\S7H
* @return Returns the page. JnBc@qnP6
*/ )x/#sW%)
public Page getPage(){ Zc~7R`v7}
return page; OU,FU@6,7w
} X<;.
o1(;"5MM
/** ,R`CAf%*
* @return Returns the users. "73y}'
*/ C+s/KA%
publicList getUsers(){ X#$ oV#
return users; La1:WYt
} -6- sI
'69)m~B0a
/** .2JZ7
* @param page }NC$Ce
* The page to set. ESV./~K
*/ Pt5 wm\
publicvoid setPage(Page page){ x/<]/D
this.page = page; /r~2KZE
} <p b
-1Li&K7
/** ZSQiQ2\)
* @param users Sr6'$8#>Y
* The users to set. fL2P6N@
*/ c2g[w;0"
publicvoid setUsers(List users){ " C0[JdZ
this.users = users; *g+ZXB
} ?`?Tg&W
i;%G Z8
/** !I?C8)
* @param userService HU?1>}4L
* The userService to set. j13-?fQ&
*/ mU4(MjP?
publicvoid setUserService(UserService userService){ c.]QIIdK
this.userService = userService; A2ye
^<-C.
} ck]I?
} aYa`ex
cOP'ql{"
e#HPU
Zt9G[[]
D*-
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, /W,hOv
(9%?ik
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 =_k
8wkhbD|;
么只需要: r[Pp[g-J
java代码: 3\m!
O.Pp*sQ^
++,I`x+p
<?xml version="1.0"?> A` _dj}UF
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6t; ;Fz
q("XS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- y60aJ)rAX
j%'2^C8
1.0.dtd"> ^oPFLez56
_=I1
<xwork> O"~[njwkE
n)5t!
<package name="user" extends="webwork- apm%\dN
m^L !_~
interceptors"> 72~L ?
}TMO>eB'
<!-- The default interceptor stack name y$7Ys:R~
%_s)Gw&sq
--> <MG&3L.[
<default-interceptor-ref kNWTM%u9
-hnNaA
name="myDefaultWebStack"/> G)s.~ T
ri4z^1\
<action name="listUser" "|(.W3f1
m@kLZimD
class="com.adt.action.user.ListUser"> "W+>?u )
<param `$jun
3mU~G}ig
name="page.everyPage">10</param> hev;M)t
<result $rW(*#C
CJN~p]\
name="success">/user/user_list.jsp</result> bh5D}w
</action> =|AYT6z,
}d}sC\>U
</package> ]
hK}ASC
%7mGMa/
</xwork> n32"cFPpT
DQ+6VPc^o
\l(J6Tu
8zeeC
eI U
>6Uc|D
JqO1 a?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 I;JV-jDM
i;{lY1
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。 '/qy_7O
^dLu#,;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 MkMDI)Y|
$Z)u04;&@
yH"i5L9
Szt2 "AR
$$ *tK8#
我写的一个用于分页的类,用了泛型了,hoho u_NLgM7*
KJyCfMH&:@
java代码: A{\?]]/
9l~D}5e7
*y?6m,38V
package com.intokr.util; 0^S$_L
AH n!>w,
import java.util.List; (y;
6H
stK}K-=`
/** 'A5T$JV.r4
* 用于分页的类<br> d`rZgY
* 可以用于传递查询的结果也可以用于传送查询的参数<br> MuMq%uDA"
* &G_#=t&
* @version 0.01 o#6QwbU25
* @author cheng LTS{[(%
*/ &C