Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 RqN_vk\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 n2y/zP>TC
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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 vA"`0
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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 msqxPC^I
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分页支持类: =~W0 ~lxX
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java代码: K5)yM @cq
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package com.javaeye.common.util; _r<zSH%
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import java.util.List; b5n]Gp
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publicclass PaginationSupport { /mMAwx
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publicfinalstaticint PAGESIZE = 30; >TlW]st
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privateint pageSize = PAGESIZE; MR?*GI's
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privateList items; j5,^9'
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privateint totalCount; *793H\
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privateint[] indexes = newint[0]; x!"SD3r=4>
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privateint startIndex = 0; =.qm8+
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public PaginationSupport(List items, int s.R-<Y3
#K:-Bys5v
totalCount){ bVa+kYE
setPageSize(PAGESIZE); 96"yNqBf
setTotalCount(totalCount); n*vTVt)dJ
setItems(items); Q)LXL.0h
setStartIndex(0); T}L^CU0
} PcHSm/d0e
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public PaginationSupport(List items, int hzT{3YtY2
vU_d=T%$
totalCount, int startIndex){ T3USNc51
setPageSize(PAGESIZE); W>5vRwx00
setTotalCount(totalCount); :]CzN^k(1c
setItems(items); ,:#,}w_HyO
setStartIndex(startIndex); @uI?
} (O)\#%,@R
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public PaginationSupport(List items, int 7|&e[@B
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totalCount, int pageSize, int startIndex){ Zg
-]sp]
setPageSize(pageSize); Awu$g.
setTotalCount(totalCount); *4<4
setItems(items); H~A"C'P3#
setStartIndex(startIndex); ~Cjz29|gp
} tigT@!`$Y
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publicList getItems(){ D(y+1^>
return items; +hE',i.
} yXJ]U
\ %
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publicvoid setItems(List items){ 96(R'^kNX
this.items = items; 2O
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} PG{i,xq_B{
:.*HQt9N
publicint getPageSize(){ "(s6aqO$
return pageSize; O0^?f/&k
} q@(1Yivk
DH
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publicvoid setPageSize(int pageSize){ H2_/,n
this.pageSize = pageSize; bS>R5*Zp
} KQ&Y2l1*>>
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publicint getTotalCount(){ tAF]2VV(e
return totalCount; O~V1Ywfq7^
} .%q$d d>>
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publicvoid setTotalCount(int totalCount){ 5sCFzo<=vh
if(totalCount > 0){ eP "`,<
this.totalCount = totalCount; xq}-m!nX
int count = totalCount / tQWWgLM
bmu6@jT
pageSize; 4'' ,6KJ@
if(totalCount % pageSize > 0) Hkdf $$\
count++; \)OEBN`9#
indexes = newint[count]; Hou*lCA
for(int i = 0; i < count; i++){ 4o<*PPA1
indexes = pageSize * YTK^ijmU6x
.}q]`<]ze
i; <47k@Ym
} Y;Ap9i*
}else{ > !L&>OOx
this.totalCount = 0; wd[eJcQ ,
} W^es;5
} ^"9*
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publicint[] getIndexes(){ 8TE>IPjm
return indexes; kbYeV_OwM
} !SO8O
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publicvoid setIndexes(int[] indexes){ dH\XO-Z7v
this.indexes = indexes; 7{e=="#*
} LH2PTW\b!6
/)EY2Y'
publicint getStartIndex(){ ](#&.q%5!
return startIndex; &fwS{n;U
} -Fxmsi
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publicvoid setStartIndex(int startIndex){ MV0Lq:# N
if(totalCount <= 0) <P_ea/5:|
this.startIndex = 0; paW@\1Q
elseif(startIndex >= totalCount) rkB'Hf
this.startIndex = indexes ujr(K=E
AQss4[\Dx
[indexes.length - 1]; "B{ECM;
elseif(startIndex < 0) \,&9
this.startIndex = 0; ~6aCfbu%V
else{ L?5f+@0.
this.startIndex = indexes EpYy3^5d
;
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[startIndex / pageSize]; El-
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} R"AUSO|{
} WGu%7e]
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publicint getNextIndex(){ _:g&,2bc
int nextIndex = getStartIndex() + 17|np2~
'zZcn" +!
pageSize; I.'b'-^
if(nextIndex >= totalCount) HYK!}&
return getStartIndex(); ;eL9{eF
else F_;DN:
{
return nextIndex; l;A,0,i
} (`BSVxJH
p(F " /
publicint getPreviousIndex(){ G:W>I=^DaR
int previousIndex = getStartIndex() - ziE*'p
bFS>)
pageSize; o|BP$P8V
if(previousIndex < 0) %+)o'nf"U
return0; bzN-*3YE=
else !v.9"!' N
return previousIndex; (ll*OVL
} :1ecx$
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} )E#2J$TD
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抽象业务类 }@1q@xU
java代码: $2^`Uca
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/** WEg6Kz
* Created on 2005-7-12 _@mRb^
*/ {`=0 |oP}
package com.javaeye.common.business; f3j{V N
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import java.io.Serializable; w%AcG~`j!B
import java.util.List; E/&Rb*3
!Z!g:II
/
import org.hibernate.Criteria; `afIYXP
import org.hibernate.HibernateException; kE8>dmH23
import org.hibernate.Session; bzDIhnw
import org.hibernate.criterion.DetachedCriteria; `@d<n
import org.hibernate.criterion.Projections; u]
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import T{qTj6I
@E( 7V(m/
org.springframework.orm.hibernate3.HibernateCallback; wbDM5%
import 7cAXd#sI
l0&EZN0V2
org.springframework.orm.hibernate3.support.HibernateDaoS CQ`=V2:"ON
9Zry]$0~R
upport; taGU
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import com.javaeye.common.util.PaginationSupport; 0]QRsVz+
c4&' D;=
public abstract class AbstractManager extends t?o,RN:
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HibernateDaoSupport { CT0l!J~5m~
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privateboolean cacheQueries = false; vZ/6\Cz
PB%-9C0
privateString queryCacheRegion; M/x >51<
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publicvoid setCacheQueries(boolean y4h=Lki@
,+`61J3W
cacheQueries){ e%8|<g+n6
this.cacheQueries = cacheQueries; p!]6ll^
} ?JL7=o
X
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publicvoid setQueryCacheRegion(String UAR5^
dKl^jsd
queryCacheRegion){ ^pM+A6
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this.queryCacheRegion = 1B),A~Ip
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queryCacheRegion; q+B&orp
} ==i[w|
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publicvoid save(finalObject entity){ u?sVcD[
getHibernateTemplate().save(entity); E}%hz*Q)(
} 4&/j|9=X
n$xQ[4eH)
publicvoid persist(finalObject entity){ :4v3\+T
getHibernateTemplate().save(entity); [ sd;`xk
} Ltjbxw"Qd
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publicvoid update(finalObject entity){ 29XL$v],
getHibernateTemplate().update(entity); k6=nO?$
} ]kG(G%r|M
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publicvoid delete(finalObject entity){ sB69R:U;
getHibernateTemplate().delete(entity); 5>AX*]c
} r-,e;o>9
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publicObject load(finalClass entity, tGB@$UmfU
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finalSerializable id){ (k np#
return getHibernateTemplate().load !x'/9^i~v
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(entity, id); Pz$R(TV
} Fd*8N8Pi
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publicObject get(finalClass entity, v9T_&
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finalSerializable id){ h<~7"ONhV
return getHibernateTemplate().get F: mq'<Q
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(entity, id); ?k(\ApVHj
} O#Wh
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publicList findAll(finalClass entity){ B7]MGXC
return getHibernateTemplate().find("from ``E/m<r:$
h,"4SSL
" + entity.getName()); 41SGWAd#:
} IUtx!.]4
qTQBt}
publicList findByNamedQuery(finalString c&L"N!4z
@O[5M2|r
namedQuery){ ;qBu4'C)T
return getHibernateTemplate M`S0u~#tI
;t+ub8
().findByNamedQuery(namedQuery); #h/Mbj~S
} n9s iX
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publicList findByNamedQuery(finalString query, VU@9@%TN
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finalObject parameter){ a5w:u5
return getHibernateTemplate ~jsLqY*(+
i E CrI3s
().findByNamedQuery(query, parameter); @/k@WhFZ
} : >>@rF ,
im @h -A]0
publicList findByNamedQuery(finalString query, /B}lO0]:
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finalObject[] parameters){ PiA0]>
return getHibernateTemplate zk( U8C+
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().findByNamedQuery(query, parameters); DY^;EZ!hb
} 4^URX>nx8
p}cw{
publicList find(finalString query){ 2p"WTd
return getHibernateTemplate().find F;]%V%F.X
71\xCSI1w&
(query); h*v8#\b$J_
} #f+$Ddg*
? YG)I;(
publicList find(finalString query, finalObject RU\/j%^
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parameter){ e2A-;4?_
return getHibernateTemplate().find R2
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(query, parameter); ' MxrQ;|S
} #{\%rWnCm
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public PaginationSupport findPageByCriteria [W7CXZDd
>:b Q
(final DetachedCriteria detachedCriteria){ qo|WXwP2
return findPageByCriteria b1($R[
GI1
(detachedCriteria, PaginationSupport.PAGESIZE, 0); z5YWt*nm
} :*KHx|Q
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public PaginationSupport findPageByCriteria )h)]SF}
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(final DetachedCriteria detachedCriteria, finalint 0ik7v<:
Dbz3;t
startIndex){ u`RI;KF~F
return findPageByCriteria H7DJ~z~J
T]c%!&^_
(detachedCriteria, PaginationSupport.PAGESIZE, .~7FyLl$
N=7pK&NHSG
startIndex);
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} #%h-[/
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public PaginationSupport findPageByCriteria q1KZ5G)6GJ
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(final DetachedCriteria detachedCriteria, finalint +O?KNZ
VG
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pageSize, Vo'T!e- B
finalint startIndex){ d\gJ$ ~^K
return(PaginationSupport) dx@-/^.
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[
getHibernateTemplate().execute(new HibernateCallback(){ M# %a(Y3K)
publicObject doInHibernate ia+oX~W!VR
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(Session session)throws HibernateException { \6 Zr
Criteria criteria = wMg0>
_ =VqrK7T
detachedCriteria.getExecutableCriteria(session); 3!|;iJRH
int totalCount = t^G"f;Ra+
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((Integer) criteria.setProjection(Projections.rowCount GQUe!G9
(<xfCH
F5
()).uniqueResult()).intValue(); lHPd"3HDK
criteria.setProjection q%"VYt4
[`"ZjkR_J
(null); +b3RkkC
List items = sg3OL/"
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criteria.setFirstResult(startIndex).setMaxResults m4hg'<<V
wc}5m
Hs
(pageSize).list(); K1+)4!}%U
PaginationSupport ps = Pama#6?OPh
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new PaginationSupport(items, totalCount, pageSize, L(|N[#
Q/(K$6]j
startIndex); `tA"
}1;ka
return ps; 1VG4S){}\9
} c|B.n]Z
}, true); :*Z4yx
} V)~.~2$
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public List findAllByCriteria(final O7-mT8o
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DetachedCriteria detachedCriteria){ =JK@z
return(List) getHibernateTemplate 8<pzb}xK
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().execute(new HibernateCallback(){ z<U-#k7nz
publicObject doInHibernate /v1Q4mq
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(Session session)throws HibernateException { wsZF;8u t
Criteria criteria = p.v0D:@&
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detachedCriteria.getExecutableCriteria(session); j,lT>/
return criteria.list(); Wz49i9e+d
} ~J wb`g.
}, true); Rg\z<wPBG
} Xqg@ e:g
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public int getCountByCriteria(final }Jy8.<Gd^
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DetachedCriteria detachedCriteria){ =9O^p@Q#W
Integer count = (Integer) C*)3e*T*
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getHibernateTemplate().execute(new HibernateCallback(){ o{* e'4
publicObject doInHibernate ,
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(Session session)throws HibernateException { 0%&1\rm+j
Criteria criteria = [R(`W#W
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detachedCriteria.getExecutableCriteria(session); WejYy|
return S!jTyY7e
]/[FR 5>
criteria.setProjection(Projections.rowCount &S{RGXj_
h58`XH
()).uniqueResult(); &zl|87M
} +%zAQeb
}, true); ~
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return count.intValue(); `18qbot
} c]x1HvPE
} Uol|9F
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bR*-Ht+wd
/ ;$#d}R
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用户在web层构造查询条件detachedCriteria,和可选的 kw>v:F<M
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 fM]+SMZy
&oP+$;Y
PaginationSupport的实例ps。 ~bM4[*Q7
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ps.getItems()得到已分页好的结果集 j`JMeCG=Ee
ps.getIndexes()得到分页索引的数组 <{dVKf,e
ps.getTotalCount()得到总结果数 yCd-9zb=
ps.getStartIndex()当前分页索引 |'.*K]Yp
ps.getNextIndex()下一页索引 nno}e/zqf
ps.getPreviousIndex()上一页索引 (|[2J3ZET
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 lW+\j3?Z$
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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 t9,\Hdo
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一下代码重构了。 X}=n:Ql'YY
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我把原本我的做法也提供出来供大家讨论吧: Uddr~2%(
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首先,为了实现分页查询,我封装了一个Page类: 9 %8"e>~
java代码: b=g8eMm
cGtO
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/*Created on 2005-4-14*/ LM$W*
package org.flyware.util.page; aO]ZZleNS
f1`gdQ)H
/** $}<PL}+
* @author Joa '{a/2
l
* fRrvNj0{V
*/ T?:Rdo!:u
publicclass Page { 52SaKA[
CpA|4'#
/** imply if the page has previous page */ j K!Au
privateboolean hasPrePage; JI? rL
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/** imply if the page has next page */ z{[xze-f
privateboolean hasNextPage; ?{\nf7Y
J{l1nHQZSu
/** the number of every page */ ZRv*!n(Ug<
privateint everyPage; ?i)f^O
!;EjB*&
/** the total page number */ O!zV)^r
privateint totalPage; +awW3^1Ed
-u&6X,Oq\u
/** the number of current page */ IM:=@a{
privateint currentPage; yW+yg{Gg:
`sUZuWL_
/** the begin index of the records by the current kd=GCO
q`|LRz&al
query */ !$DIc
privateint beginIndex; 8;z6=.4xtg
b^ L
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/** The default constructor */ /,1D)0
public Page(){ =CK4.
<DMl<KZ
} QZ4v/Ou
9!f/aI
/** construct the page by everyPage ~1cnE:x;V
* @param everyPage 3Dg,GaRk
* */ v$~QU{&
public Page(int everyPage){ y]2qd35u_A
this.everyPage = everyPage; xgABpikC^
} @'YS1 N<
U3 */v4/
/** The whole constructor */ 09dK0H3(
public Page(boolean hasPrePage, boolean hasNextPage, B,M(@5wz
y@ ML/9X8q
4 d;|sI@
int everyPage, int totalPage, )_1zRT| 9
int currentPage, int beginIndex){ \x)n>{3C
this.hasPrePage = hasPrePage; W^fuScG)c
this.hasNextPage = hasNextPage; Q&MZN);.
this.everyPage = everyPage; qi;f^9M%
this.totalPage = totalPage; &@%W29:
this.currentPage = currentPage; 8S>&WR%jH]
this.beginIndex = beginIndex; AP[|Ta
} {8 8 )~
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/** ="x\`+U
* @return LAVAFlK5
* Returns the beginIndex. HkQ*y$$
*/ Vm%1> '&
publicint getBeginIndex(){ aD=a ,
return beginIndex; EPS={w$'s
} )A!>=2M`
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/** ~(x;5{
* @param beginIndex Ae69>bkE0
* The beginIndex to set. vLR~'"`F
*/ A6GE,FhsG
publicvoid setBeginIndex(int beginIndex){ =3q/F7-
this.beginIndex = beginIndex; f~Fm4>\(
} "J+3w
5nv<^>[J
/** ()K " c#
* @return ) _mr! z(S
* Returns the currentPage. U"q/rcA
*/ 3= xhoRX
publicint getCurrentPage(){ /GIxR6i
return currentPage; *:>"q ej
} /DQc&.jK
1"/He ` 4
/** Ynp{u`?
* @param currentPage Vl%^H[]
* The currentPage to set. R<sJ^nx
*/ p[<Dk$7K
publicvoid setCurrentPage(int currentPage){ A$#p%yb
this.currentPage = currentPage; dY@WI[yog
} Hu.t 3:w
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/** F;=4vS]\
* @return (4'$y`Z
* Returns the everyPage. bhkUKxd
*/ Eq$&qV-?(
publicint getEveryPage(){ zunV<2~(2}
return everyPage; Mu{;vf|j
} _@
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IX*idcxR
/** w=LP"bqlI
* @param everyPage ##@$|6
* The everyPage to set. H|RT?Q
*/ {Zh>mHW3
publicvoid setEveryPage(int everyPage){ #ggf' QIHp
this.everyPage = everyPage; .pfP7weQ
} 6)vSG7Ise
jV?
}9L^;
/** TUHi5K
* @return q4}PM[K?=\
* Returns the hasNextPage. QmLF[\Oo_
*/ ,$'])A?$
publicboolean getHasNextPage(){ ]%BWIqbr
return hasNextPage; 8zA=;~GHP
} .k
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/** UB 6mqjPK
* @param hasNextPage UW9?p}F
* The hasNextPage to set. L=q+|j1>
*/ %^1cyk
publicvoid setHasNextPage(boolean hasNextPage){ Q$:![}[(
this.hasNextPage = hasNextPage; X{we/'>
} .&9 i
hGbj0
/** N\HQN0d9
* @return 1Wm)rXW[x
* Returns the hasPrePage. mt5KbA>nU
*/ ]J:1P`k.
publicboolean getHasPrePage(){ ~=KJzOS,S
return hasPrePage; ={5#fgK>
} uu}x@T@
Q%wY
/** /v/C<]
* @param hasPrePage wKi^C8Z2
* The hasPrePage to set. ^bc;[x&N
*/ $&<uT
publicvoid setHasPrePage(boolean hasPrePage){ ,RgB$TcE
this.hasPrePage = hasPrePage; ]~6_ WE8L
} .\8X[%K9nc
x7vctjM|
/**
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* @return Returns the totalPage. t=u
Qb=
* o99pHW(E
*/ >0dv+8Mn
publicint getTotalPage(){ N.4q.
return totalPage; <JV"@H=
} ZVbl88,(l
X^\>:<
/** cwm_nQKk
* @param totalPage KAsS[
* The totalPage to set. 9_QP !,
*/ j:}D Bk
publicvoid setTotalPage(int totalPage){ ?x+Z)`w_
this.totalPage = totalPage; iSFuT7;%
} M.nvB)
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} A<6%r7&B'
P\]B<
R-Z~V
,^gyH
\
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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 `xz<>g9e
R(-<BtM!-
个PageUtil,负责对Page对象进行构造: $5v0m#[^
java代码: .`7cBsXH
r?CI)Y;
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/*Created on 2005-4-14*/ 7HVZZ!>~
package org.flyware.util.page; @]qBF]6
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import org.apache.commons.logging.Log; .i^7|o:
import org.apache.commons.logging.LogFactory; CiR%Ujf
p-%|P]&
/** xr7+$:>a
* @author Joa JT9N!CGZ
* lc_E!"1
*/ hoT/KWD,
publicclass PageUtil { {V1Pp;A
y7S4d~&
privatestaticfinal Log logger = LogFactory.getLog /T,Z>R
.>wv\i[p
(PageUtil.class); Fb/XC:AD
BS&;n
/** ^'p|!`:
* Use the origin page to create a new page k'$!(*]\b
* @param page R.LL#u};
* @param totalRecords U!XS;a)
* @return 0aoHKeP
*/ k z"3ZDR
publicstatic Page createPage(Page page, int eZr&x~]
-w
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totalRecords){ "lNzGi-H
return createPage(page.getEveryPage(), <`!PCuR
9s}Kl($
page.getCurrentPage(), totalRecords); BZb]SoAL
} q>s-Y|
ri1C-TJM)
/** p"*y58
* the basic page utils not including exception 0F#>CmD
]O{u tm
handler T@%m7 |P
* @param everyPage FuX 8v
* @param currentPage qn"D#K'&(
* @param totalRecords tn|,O.t
* @return page 1Uf*^WW4
*/ ?3Ij*}_O2
publicstatic Page createPage(int everyPage, int 5cK@WE:
mL~z~w*s
currentPage, int totalRecords){ XT,#g-oi
everyPage = getEveryPage(everyPage); nK3k]gLc{
currentPage = getCurrentPage(currentPage); e75UMWaeC
int beginIndex = getBeginIndex(everyPage, AGYm';z3
ni
currentPage); ZyR_6n>L$
int totalPage = getTotalPage(everyPage, K?#]("De6
Je4Z(kj 0
totalRecords); Q36)7=at
boolean hasNextPage = hasNextPage(currentPage, rZ_>`}O2
Io2mWvu?5
totalPage); ^IgY d*5
boolean hasPrePage = hasPrePage(currentPage); 1Q}mf !Y
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returnnew Page(hasPrePage, hasNextPage, ?p[O%_Xf
everyPage, totalPage, 92dF`sv
currentPage, d~ng6pA
*.f2VQ~H
beginIndex); r)1Z(tl
} (I{
$kB"p
=QV::/
privatestaticint getEveryPage(int everyPage){ h5|.Et
return everyPage == 0 ? 10 : everyPage; H L<s@kEZ
} v7trr W}
`PI(%N
privatestaticint getCurrentPage(int currentPage){ tPuut\ee
return currentPage == 0 ? 1 : currentPage; j<tq1?? [b
} h`MdKX$
w#G2-?aj
privatestaticint getBeginIndex(int everyPage, int a0Oe:]mo\
sCH)gr@gJ^
currentPage){ U; xF#e
return(currentPage - 1) * everyPage; lx,`hl%
} J/D|4fC
Mxz,wfaH>
privatestaticint getTotalPage(int everyPage, int ['X[qn
j kn^Z":
totalRecords){ 96|[}:+$&:
int totalPage = 0; Q]JX`HgPaU
?Z %:
if(totalRecords % everyPage == 0) yOHXY&
totalPage = totalRecords / everyPage; Mpx/S<Z
else )3?rXsSR
totalPage = totalRecords / everyPage + 1 ; T|'&K:[TJ
L&w.j0fq
return totalPage; Jj"HpK>[
} :.IN?X
A! 6r/
privatestaticboolean hasPrePage(int currentPage){ 9q4_j
return currentPage == 1 ? false : true; X:q_c =X
} H/cTJ9zz
6* rcR]
privatestaticboolean hasNextPage(int currentPage, BTs0o&}e
okDJ(AIV+
int totalPage){ >&*6Fqd
return currentPage == totalPage || totalPage == LBW.*PHW
l
:f9Ih
0 ? false : true; }K#iCby4
} pI'8>_o
&gY;`*<
8yY"x
['
} B)(p9]q
U;x99Go:
{KF 7j63
3N(8|wh
Ej;Vr~Wi
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 N{?Tm`""
]s1TJw [B
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 trID#DT~
U'JP1\
做法如下: >VpP/Qf
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 rU/-Wq`B
U)&H.^@r$
的信息,和一个结果集List: q$e
T!'x
java代码: jEC'l]l
{ Hktu|
u!=]zW%
/*Created on 2005-6-13*/ 'US:Mr3
package com.adt.bo; `XQx$I
\#h})`
import java.util.List; 8cYuzt]..
yb@X*PW/z
import org.flyware.util.page.Page; cP}5}+
GV `idFd
/** I v 80,hW
* @author Joa (E2lv#[
*/ m)tI
publicclass Result { :X1`wBu
:epitpJ
private Page page; *~\;&G29Y
0lvb{Zd
private List content; OF<[Nh\.
rRF+\cP?.
/** C9"f6>i
* The default constructor qiwQUm{
*/ YyX^lL_
public Result(){ ];YglHH
super(); T1g:gfw@
} ;iwD/=Y
7;$L&X
/** )[^:]}%r
* The constructor using fields f4@#pnJ3po
* D9@<#2-
* @param page ,=XS%g}l4
* @param content YQfZiz}Fv
*/ 'xu7AKpU)
public Result(Page page, List content){ +ik N) D
this.page = page; IArpCF/"8
this.content = content; 0*]<RM
} cSH tl<UY
7@e[:>e
/** s525`Q;
* @return Returns the content. Hsux>+Q
*/ NZi'eZ{^`
publicList getContent(){ 5BGv^Qb_2
return content; [\w>{
} s]V{}bY`
FrE/K_L
/** lzQ&)7`
* @return Returns the page. S4uR\|
*/ Z)Xq!]~/g
public Page getPage(){ 9Rt(G_'
return page; y+~Aw"J}
} /fcwz5~
sB*h`vs0T
/** _#\5]D~""
* @param content ]>]H:NEq
* The content to set. _oyL*Cb
*/ YRT}fd>R&
public void setContent(List content){ 8)2u@sx%
this.content = content; 8mQd*GGu1
} 2[bR6 T89
r:S5x. P2
/** s$=B~l
* @param page n
B|C-.F
* The page to set. fSb@7L
*/ WY ^K7U
publicvoid setPage(Page page){ DQHGq_unP
this.page = page; :fMM-?s]
} gs2&0rnOy\
} q=i,'.nS
jl?y}
70 DQ/b
A5J#x6@
D\i8rqU/l
2. 编写业务逻辑接口,并实现它(UserManager, hF?\K^tF
Yv|bUZ@
UserManagerImpl) Q!$kUcky9
java代码: J1wGK|F~
!&<Wc^PG
ohG43&g~
/*Created on 2005-7-15*/ DyV[+P
package com.adt.service; #on fac- 3
8C4@V[sm`
import net.sf.hibernate.HibernateException; (>/Dw|,m
jl|X$w
import org.flyware.util.page.Page; Uu<sntyv
"Mu$3w
import com.adt.bo.Result; k@X
As
Tr+Y@]"
/** ;Q%19f3,6
* @author Joa s</ktPtu
*/ tLGwF3e$A
publicinterface UserManager { E9NGdp&-Ah
3_['[}
public Result listUser(Page page)throws |x~ei_x7.p
[;\<
2 =H
HibernateException; >Sl:Z ,g;
>!WBlSy
} \~m%4kzG8J
o3`gx
*xX0]{49q
zj0pP{y
I2!&=" 7@
java代码: qv >(
Bk(XJAjY
\y+F!;IxL
/*Created on 2005-7-15*/ vt7C
package com.adt.service.impl; 0Nzv@g{3
aIyY%QT
import java.util.List; Ib<+m%Ac
m_W.r+s~C4
import net.sf.hibernate.HibernateException; +R jD\6bJb
[75e\=wK
import org.flyware.util.page.Page; k{$"-3ed
import org.flyware.util.page.PageUtil; p~VW3u]
0&~u0B{
import com.adt.bo.Result; TDq(%IW
import com.adt.dao.UserDAO; M<4~ewWJ
import com.adt.exception.ObjectNotFoundException; mbK$_HvU
import com.adt.service.UserManager; {}y"JbXMj
>/9f>d?w^
/** ,C1}gPQ6<
* @author Joa vlY83mU.
*/ S=@.<gS
publicclass UserManagerImpl implements UserManager { #`?B:
DD{-xCCR
private UserDAO userDAO; * G!C 'w\$
=dSH8C"
/** CB]#`|f
* @param userDAO The userDAO to set. )!z<q}i5
*/ @8{-B;
publicvoid setUserDAO(UserDAO userDAO){ ;89 `!V O
this.userDAO = userDAO; Wa7-N4
} +"Flu.+['
gqJSz}'
/* (non-Javadoc) ^YiGvZJ
* @see com.adt.service.UserManager#listUser K[r<-6TS
3 }~.#`QeY
(org.flyware.util.page.Page) N@6+DHt
*/ lLhvpvT
public Result listUser(Page page)throws jMr [UZ
*oZ]k`-!8
HibernateException, ObjectNotFoundException {
]wb^5H
int totalRecords = userDAO.getUserCount(); 3Z/_}5%"
if(totalRecords == 0) RC?gozBFJ
throw new ObjectNotFoundException ZEa31[@B[
pDqX%
$^
("userNotExist"); wr>[Eo@%\
page = PageUtil.createPage(page, totalRecords); Z$jqB~=^e
List users = userDAO.getUserByPage(page); m#w1?y)Z@X
returnnew Result(page, users); 1seWR"
} |z1er"zR)
uIh68UM
} ,Y9bXC8+dU
~i_YrTp
-4wr)zjfW
[QUaC3l)
X6 E^5m
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 AwnQ5-IR\
PzF>yG[
询,接下来编写UserDAO的代码: gi {rqM
3. UserDAO 和 UserDAOImpl: u-</G-y
java代码: 4,EX2
=)b!M^=X-a
(:er~Y}
/*Created on 2005-7-15*/ (E(J}r~E
package com.adt.dao; D*=.;Rq
<8)cr0~zy>
import java.util.List; -A]-o
GY`mF1b
import org.flyware.util.page.Page; xQUskjv/
(>49SOu;$\
import net.sf.hibernate.HibernateException; g79zzi-
!#y_vz9
/** UpTVLx^c
* @author Joa c,j[ix
*/ f/PqkHF
publicinterface UserDAO extends BaseDAO { E4N/or
h-.xx4D
publicList getUserByName(String name)throws Lm&BT)*
~`97?6*Ra
HibernateException; [_HY6gr
=O%Hf bx
publicint getUserCount()throws HibernateException; x$hT+z6DUC
P9
w);jp;
publicList getUserByPage(Page page)throws FW"n+7T
kk>z,A4
h_
HibernateException; 1SF8D`3
&K*Kr=9N
} 1K#%mV_
;,lFocGv
,Dab(
[a_'pAH
?zuKVi?I
java代码: gb{8SG5ac
}Y"vUl_I2
zx/$
/*Created on 2005-7-15*/ ]T<tkvcI
package com.adt.dao.impl; f"z;'
r]0>A&,
import java.util.List; <2af&-EGs
d`UK mj
import org.flyware.util.page.Page; dY{qdQQ}
p`2Q6
import net.sf.hibernate.HibernateException; oFb~|>d
import net.sf.hibernate.Query; k:F{U^!p|
I5@8=rFk
import com.adt.dao.UserDAO; Kzx`
E>,z'
I~GHx5Dk
/** ]D&U}n
* @author Joa <naxpflom0
*/ #UymD-yII
public class UserDAOImpl extends BaseDAOHibernateImpl ,B/TqPP
B&X)bGx8
implements UserDAO { ^Ff fc@=
0K.$C~C
/* (non-Javadoc) Et*LbU
* @see com.adt.dao.UserDAO#getUserByName UV;I6]$}A7
$<Gt^3e
(java.lang.String) e[T3,2C
*/ 7YTO{E6]d\
publicList getUserByName(String name)throws C'A
D[`p
sOWP0xY
HibernateException { iWW!'u$+I`
String querySentence = "FROM user in class LL3| U
2xuU[
com.adt.po.User WHERE user.name=:name"; 5ip ZdQ^
Query query = getSession().createQuery |Zn,|-iW
u];\v%b
(querySentence); fvTp9T\f3
query.setParameter("name", name); j/uMSE
return query.list(); U/U_q-z]
} }o
GMF~
ZyC[w7$I2
/* (non-Javadoc) U.^%7.
* @see com.adt.dao.UserDAO#getUserCount() PB8U+
*/ :WH0=Bieh
publicint getUserCount()throws HibernateException {
!&KE">3Qu
int count = 0; dXt@x8E
String querySentence = "SELECT count(*) FROM }/NL"0j+4
&{M-<M
user in class com.adt.po.User"; f]Z9=
Query query = getSession().createQuery 2+(SR.oGq
/WAOpf5
(querySentence); Cq=k3d#}
count = ((Integer)query.iterate().next S|RUc}(
P)=$0kR3
()).intValue(); r)qow.+&
return count; = p2AK\
} =cR=E{20
14-uy.0[
/* (non-Javadoc) ;2eZa|M*q
* @see com.adt.dao.UserDAO#getUserByPage ss7Z-A 4z
a=^>A1=
(org.flyware.util.page.Page) 60p*4>^v
*/ 5=_))v<Tp
publicList getUserByPage(Page page)throws ZoKX ao
VelX+|w
HibernateException { R?,XSJ
String querySentence = "FROM user in class 7LW%:0
Q;p%
VQ
com.adt.po.User"; TbR
Ee;1
Query query = getSession().createQuery 8bEii1EM
0_map z
(querySentence); /{X2:g {
query.setFirstResult(page.getBeginIndex()) y"0!7^
.setMaxResults(page.getEveryPage()); @z.HyQ_v
return query.list(); Xu5^ly8p9q
} 71yf+xL
G?{uR6s>#
} PHn3f;I
yYZ0o.<&T*
2Yd;#i)
e~BUAz
#]o#~:S=
至此,一个完整的分页程序完成。前台的只需要调用 :.EVvuXI
yB^_dE
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z0%Qy+%
m3K .\3
的综合体,而传入的参数page对象则可以由前台传入,如果用 pSJc.j
A@ lY{e
webwork,甚至可以直接在配置文件中指定。 IOOAaa @(
::rKW*?
下面给出一个webwork调用示例: _"%-=^_
java代码: BIjQ8 t
2r&T.
Tj*Vk $}0
/*Created on 2005-6-17*/ 5S?+03h~
package com.adt.action.user; U
ORoj )$I
rYMHc@a9(
import java.util.List; o}K!p%5_
eyGY8fF8$
import org.apache.commons.logging.Log; 5}t}Wc8
import org.apache.commons.logging.LogFactory; |cE 69UFB
import org.flyware.util.page.Page; Z6`[dAo
hzjEO2
import com.adt.bo.Result; ]RJcY1
import com.adt.service.UserService; IvyBK]{|
import com.opensymphony.xwork.Action; AR-&c 3o
L.@o
/** 4U;6 2 jq
* @author Joa qj5V<c;h%W
*/ L(2KC>GvA
publicclass ListUser implementsAction{ pkL&j<{
IA XoEBlMs
privatestaticfinal Log logger = LogFactory.getLog .:b|imgiv
M1/Rba Q
(ListUser.class);
5 5_#?vw
Q,mmHw.`J
private UserService userService; VSlIeZ
[l2ds:
private Page page; (hn@+hc
U
h'1f7%
privateList users; ./009p
DhwFD8tT
/* l25E!E-'b
* (non-Javadoc) jz%%r Q(
* 2%'iTXF
* @see com.opensymphony.xwork.Action#execute() 0OndSa,
*/ f"j"ZM{~U
publicString execute()throwsException{ Fx.hti
Result result = userService.listUser(page); D,rF?t>=S
page = result.getPage(); ^f-?xXPx
users = result.getContent(); n'yC- ;
return SUCCESS; ;/3
<
} 8T:|~%Sw
X/_e#H0
/** Jbud_.h9
* @return Returns the page. 8v},&rhPQq
*/ n y7G
public Page getPage(){ tTT./-*0
return page; R)AFaP |
} Z^w}: {
(=d%Bn$6b
/** 2Rc'1sCth-
* @return Returns the users. $z!o&3c'x
*/ D6trqB
publicList getUsers(){ `zNvZm -E
return users; \$o!M1j
} wz-9+VN6
w`(EW>i
/** ANNfL9:Jy
* @param page ;?>xuC$
* The page to set. @'.(62v
*/ ~VZ)LQ'7
publicvoid setPage(Page page){ iV!o)WvG,F
this.page = page; j$ h.V#1z
} `B{N3Kxbp
zPp?D_t
/** PpPg ~ix*
* @param users seh1(q?Va4
* The users to set. <StyO[
*/ }Yt/e-Yg%r
publicvoid setUsers(List users){ a"^0;a
this.users = users; 5Z]zul@+*
} D2 o,K&V
eRkvNI
/** %./vh=5)
* @param userService tG(# &54
* The userService to set. .lVC>UT
*/ 0?} ),8v>
publicvoid setUserService(UserService userService){ jm1f,=R
this.userService = userService; (9r\YNK
} b4GD}kR
} xSFY8
fZK&h.
GAONgz|ZI
1!,xB]v1Ri
gs)wQgJ [
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, t#tAvwFM8
L&O!"[++
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 6/^$SWd2
S'>(4a
么只需要: \}SA{)
java代码: Xx_v>Jn!
$]IX11.m
p=m) lR9
<?xml version="1.0"?> ZS0=xS5q)
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork DIR_W-z
4fPbwiKj
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ^FO&GM2a
< cNJrer
1.0.dtd"> Ife/:v
!2YvG%t^6
<xwork> -^C^3pms
. W ~&d_n
<package name="user" extends="webwork- UNK}!>HD
VsIDd}~C%
interceptors"> 10?+6*d
r}?uZ"]=?
<!-- The default interceptor stack name Fa]|Y
H3Ws$vl9n
--> 5?] Dn k.o
<default-interceptor-ref %%uvia=e
2~ [
name="myDefaultWebStack"/> Q)mYy
>#u9W'@|
<action name="listUser" }\#u~ k!l
qDlh6W?}k
class="com.adt.action.user.ListUser"> Vt4KG+zm
<param ;W~H|M
NeI#gJ1A
name="page.everyPage">10</param> 4,g[g#g<q
<result YY4XCkt
xLN$!9t
name="success">/user/user_list.jsp</result> V*d@@%u**
</action> z^,P2kqK_
NCX`-SLv
</package> = Z
/*
x<Ac\Cx
</xwork> _keI0ML-#
u{J\X$]
}uFV\1
u2o196,Ut
dy"7Wl]hi7
As>-9p>v
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 '.gLqm}%
{ POfT
m}
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。 K^m`3N"
# A#,]XP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 V*,6_-^l
ZCAg)/
k*u4N
Ewq7oq5:
N2uTWT>
我写的一个用于分页的类,用了泛型了,hoho TQL_K8k@_
qZ<|A%WQ
java代码: !QsmT3
pY$DOr-r`
1$n!Lj=5
package com.intokr.util; Ha/Gn!l
u
OB`A-K
import java.util.List; dF+R
q|n{
1 ~s$<
/** [A'9sxG
* 用于分页的类<br> 0RF<:9@x2
* 可以用于传递查询的结果也可以用于传送查询的参数<br>
3J}/<&wv
* 9jJ:T$}
* @version 0.01 O_P8OA#|
* @author cheng q^Ui2
*/ [pzo[0G 'v
public class Paginator<E> { yP "D~u
privateint count = 0; // 总记录数 _zG[b/:p
privateint p = 1; // 页编号 1#V&'A
privateint num = 20; // 每页的记录数 XQStlUw8+
privateList<E> results = null; // 结果 ? oQ_qleuo
^K?Mq1"Db
/** h,x'-]q
* 结果总数 CuAA)B j
*/ :^ J'_
publicint getCount(){ vq8&IL
return count; 9$ =o({
} t}>"nr0
~+&Z4CYb
publicvoid setCount(int count){ (;2]`D [x
this.count = count; *3h!&.zm
} MuP&m{
7NP
Ny
/** Lb0B m R%0
* 本结果所在的页码,从1开始 m<GJ1)%3i
* KFf6um
* @return Returns the pageNo. p77
*/ 9 UcSQ"D
publicint getP(){ (k<__W c_t
return p; vx4Jk]h+=L
} 1J[|Ow
P7y.:%DGD0
/** Ir$:e*E>
* if(p<=0) p=1 &DX
* 11BfJvs:
* @param p }Oe9Zq
*/ ?gl[=N V
publicvoid setP(int p){ `dm}|$X|
if(p <= 0) nhI1`l&
p = 1; T)#eaz$4W
this.p = p;
A9C
} Pskg68W
|C3~Q{A
/** '/Ag3R
* 每页记录数量 Bw*6X`'Q
*/ Nh+ZSV4WJ:
publicint getNum(){ Z >F5rkJ
return num; }8?1)l
} x[1(cj
XZ1WY(
/** SAtK 'Jx[
* if(num<1) num=1 ;&U! g&
*/ &dvL`
publicvoid setNum(int num){ 707-iLkt.1
if(num < 1) :P:OQ[$
num = 1; -?PXj)<
this.num = num; RMO6k bfP
} 0OPpA Ll
Y|y X]\,
/** h0n,WU/Kw
* 获得总页数 0Rze9od]$
*/ SM@RELA'Lb
publicint getPageNum(){ /ng+IC3
return(count - 1) / num + 1; okv`v
({
} _/%,ZoZ2
sPUn"7
/** ';OZP2
* 获得本页的开始编号,为 (p-1)*num+1 f]JLFg7
*/ W\'njN
publicint getStart(){ jRswGMx
return(p - 1) * num + 1; X5@SLkJ-`
} n{>Ge,enP0
Qy)+YhE
/** IL:d`Kbqf
* @return Returns the results. 0W asE1t|
*/ ZP@or2No%
publicList<E> getResults(){ DCJmk6p%0
return results; _RLx;Tn)L
} }{! #`'s
KGMX >t'
public void setResults(List<E> results){ wq|~[+y
this.results = results; [m9Pt]j@
} ISQC{K']J
$/\b`ID
public String toString(){ U($sH9,
StringBuilder buff = new StringBuilder 16iymiLz&
'bH',X8gF
(); $jt UQ1
buff.append("{"); IrAc&Eh