Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;;$# )b
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =$8nUX`
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 tj]9~eJ-
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 K
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分页支持类: I|-p3g8\
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java代码: Ll4bdz,
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package com.javaeye.common.util; '$As<LOEd/
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import java.util.List; oBq 49u1
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publicclass PaginationSupport { }ZSQ>8a
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publicfinalstaticint PAGESIZE = 30; MaBYk?TR~
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privateint pageSize = PAGESIZE; /:6Wzj
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privateList items; -"Y{$/B
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privateint totalCount; 2-zT$`[]J
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privateint[] indexes = newint[0]; Ee1LO#^_6
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privateint startIndex = 0; 0c.s
-
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public PaginationSupport(List items, int t&5%?QyM
be5,U\&z
totalCount){ VN0mDh?E
setPageSize(PAGESIZE); iVFkYx%}
setTotalCount(totalCount); nhSb~QqEh
setItems(items); 04%S+y.6&Y
setStartIndex(0); &|%6|u9
} ]`g<w#
rPc7(,o*
public PaginationSupport(List items, int w#JJXXQI
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totalCount, int startIndex){ y~
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setPageSize(PAGESIZE); =Cv/Y%DN
setTotalCount(totalCount); o]{uc,
setItems(items); PN~@
setStartIndex(startIndex); S.B<pjgt
} }pkj:NT
3ZTE<zRQ
public PaginationSupport(List items, int
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q'oMAM f}
totalCount, int pageSize, int startIndex){ zL5d0_E9
setPageSize(pageSize); 8,O33qwH
setTotalCount(totalCount); Gc.P,K/hr
setItems(items); 2nb:)
setStartIndex(startIndex); ;o/>JHGj
}
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publicList getItems(){ _8}QlT
return items; zJ+8FWy:S
} ,U)"WLmY
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publicvoid setItems(List items){ T9 <2A1
this.items = items; &2-L.Xb
} nFX_+4V2
4RKW
publicint getPageSize(){ PUQES(&
return pageSize; Fg$3N5*
} o!Ev;'D
juAMAplf
publicvoid setPageSize(int pageSize){ dX8hpQ
this.pageSize = pageSize; #B'aU#$u
} + SZYg[
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publicint getTotalCount(){ q;5i4|
return totalCount; 6b8;}],|
} EzW)'Zzw~
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publicvoid setTotalCount(int totalCount){ !KKT[28v
if(totalCount > 0){ k^$+n_
this.totalCount = totalCount; J68j=`Y
int count = totalCount / q0%
wn
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pageSize; at!Y3VywG
if(totalCount % pageSize > 0) l?Y_~Wuw
count++; U%7i=Z{^Ks
indexes = newint[count]; |vte=)%
for(int i = 0; i < count; i++){ &"_u}I&\
indexes = pageSize * ERUt'1F?]
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i; I O%6 O
} 0.r4f'vk
}else{ #8{F9w<Rf
this.totalCount = 0; !>x|7
} [w
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} |CgnCUv+
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publicint[] getIndexes(){ U(&oj e
return indexes; y#Ht{)C
} \&V0vN1
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publicvoid setIndexes(int[] indexes){ ~5ZvOX6L2
this.indexes = indexes;
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} jO9ip
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publicint getStartIndex(){ d-bqL:/
return startIndex; oq-<ob
} d;tkJ2@NO
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publicvoid setStartIndex(int startIndex){ E< 4l#Z<
if(totalCount <= 0) ;;5Uwd'-
this.startIndex = 0; 1ju#9i`.Wg
elseif(startIndex >= totalCount) Kzy/9
this.startIndex = indexes BhpOXqg
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N}j
[indexes.length - 1]; 5q{h 2).)
elseif(startIndex < 0) tC8(XMVx
this.startIndex = 0; O^LTD#}$a)
else{ u{&B^s)k.
this.startIndex = indexes !DjvsG1x
{-9jm%N
[startIndex / pageSize]; ^\ ?O4,L
} +&tgJ07A
} Q8p&Ki;i
U]qav,^[
publicint getNextIndex(){ 78n=nHS
int nextIndex = getStartIndex() + 2^~<("+w
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pageSize; < (RC|?
if(nextIndex >= totalCount) x+? 9C
return getStartIndex(); TAL/a*7\
else vv6$>SU
return nextIndex; [\)oo
} sKLX [l
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publicint getPreviousIndex(){ rh2LGuo4m
int previousIndex = getStartIndex() - 39e;
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pageSize; .F&9.#>
if(previousIndex < 0) 9L%I<5i
return0; MFJE6ei
else |6biq8|$3V
return previousIndex; -0o[f53}p
} c- $Gpa}M
n9LGP2#!
} /4=-b_2Y~
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抽象业务类 fLN! EDq
java代码: VeiElU3
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{ PlK@#UN
/** (%ew604X
* Created on 2005-7-12 X{Yw+F,j
*/ >QQ(m\a$
package com.javaeye.common.business; KYJ1}5n
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import java.io.Serializable; '6Qy /R
import java.util.List; qg z*'_S
k>4qkigjc
import org.hibernate.Criteria; OQ/<-+<w
import org.hibernate.HibernateException; X CB?ll*^
import org.hibernate.Session; E
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import org.hibernate.criterion.DetachedCriteria; rt]S\
import org.hibernate.criterion.Projections; [c K^+s)N
import *#>F.#9
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org.springframework.orm.hibernate3.HibernateCallback; g]mtFrP
import s}M= oe
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org.springframework.orm.hibernate3.support.HibernateDaoS \v@({nB8
n_[i0x7#
upport; .W\ve>;
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import com.javaeye.common.util.PaginationSupport; Ob +9W
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public abstract class AbstractManager extends 3{raKM6F
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HibernateDaoSupport { (Ha@s^?.C
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privateboolean cacheQueries = false; ! U0z"
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privateString queryCacheRegion; `&7RMa4=
r >{G`de4
publicvoid setCacheQueries(boolean 0V,Nv9!S
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cacheQueries){ Lrz3
this.cacheQueries = cacheQueries;
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} I\P Bu$Ww
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publicvoid setQueryCacheRegion(String /4S;QEv
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queryCacheRegion){ BW[5o3
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this.queryCacheRegion = =y ]Jl,_.
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queryCacheRegion; cH`^D?#se
} qV1O-^&[f=
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publicvoid save(finalObject entity){ ~2}Pl)
getHibernateTemplate().save(entity); oVkq2
} @Z(rgF{{
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publicvoid persist(finalObject entity){ $`Nd?\$
getHibernateTemplate().save(entity); '8`T|2
} S0w> hr
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publicvoid update(finalObject entity){ j\)H
getHibernateTemplate().update(entity); W*T{,M@Y
} -/{af
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publicvoid delete(finalObject entity){ I=dGq;Jaz
getHibernateTemplate().delete(entity); ?qHF}k|
} e$l6gY
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publicObject load(finalClass entity, 4Kp L>'Q=
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finalSerializable id){ J%v5d*$.
return getHibernateTemplate().load GG-[`!>.pw
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(entity, id); W|c.l{A5Q
} gp
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publicObject get(finalClass entity, "e62/Ejg%
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finalSerializable id){ 1$LI px
return getHibernateTemplate().get crmUrF#
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(entity, id); >q( 5ir
} [B/0-(?
,"
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publicList findAll(finalClass entity){ KsdG(.I+ek
return getHibernateTemplate().find("from TQ9'76INb
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" + entity.getName()); rg&+
} Vu]h4S :
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publicList findByNamedQuery(finalString |HbEk[?^s
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namedQuery){ Wc'Ehyi;
return getHibernateTemplate vZjZb(jlN
: }?{@#Z
().findByNamedQuery(namedQuery); #s"B-sWE
} #}o<v|;
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publicList findByNamedQuery(finalString query, i ^|@"+
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finalObject parameter){ MV936
return getHibernateTemplate b~Z=:'m8
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().findByNamedQuery(query, parameter); y4F^|kS) [
} ,b'4CF
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publicList findByNamedQuery(finalString query, f'{>AKi=C
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finalObject[] parameters){ 'U)8rR
return getHibernateTemplate :m`/Q_y"
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().findByNamedQuery(query, parameters); sbla`6Fb
} Yo2Trh
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publicList find(finalString query){ Pz473d
return getHibernateTemplate().find {'~sS
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(query); %W;u}`
} vjTwv+B"
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publicList find(finalString query, finalObject \3^Pjx
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parameter){ /yYlu
return getHibernateTemplate().find Ak=UtDN[
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(query, parameter); G[6=u|(M
} tA qs2
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ eTZ`q_LfI1
return findPageByCriteria i QqbzOY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); G%OpO.Wf
} v*DFiCQD
TN ci.']
public PaginationSupport findPageByCriteria l<RfRqjw
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(final DetachedCriteria detachedCriteria, finalint SJ(9rhB5*.
%HEmi;
startIndex){ a;p6?kv
return findPageByCriteria % +8
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(detachedCriteria, PaginationSupport.PAGESIZE, lIl9ypikg
7.|S>+Q
startIndex); `Kp}s<
} s5.k|!K
ayH>XwY6
public PaginationSupport findPageByCriteria y''V"Be
<4NQL*|>
(final DetachedCriteria detachedCriteria, finalint zjWyGt(Q
}85#[~m'
pageSize, nO
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finalint startIndex){ nDn{zea7
return(PaginationSupport) KgU[
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getHibernateTemplate().execute(new HibernateCallback(){ *2:Yf7rvI+
publicObject doInHibernate mt .,4
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(Session session)throws HibernateException { o}R|tOe
Criteria criteria = :eLLDp<
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detachedCriteria.getExecutableCriteria(session); },3R%?89%
int totalCount = D4\(:kF\Hg
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((Integer) criteria.setProjection(Projections.rowCount dh,7iQ
s
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()).uniqueResult()).intValue(); \]GGVI;u
criteria.setProjection "b;k.Fx
bgXc_>T6_y
(null); 2 ^ kn5
List items = s.ey!ew
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criteria.setFirstResult(startIndex).setMaxResults [r~~=b7*[
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(pageSize).list(); Faw. GU
PaginationSupport ps = Q
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new PaginationSupport(items, totalCount, pageSize, WFks|D:sB
%,E7vYjT%
startIndex); fa.f(c
return ps; L%4tw5*N
} zN/Gy}
}, true); Xa6qvg7/
} t9n'!
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public List findAllByCriteria(final ],#ZPUn
m&{rBz0
DetachedCriteria detachedCriteria){ $q=hcu
return(List) getHibernateTemplate ^:$j:w?j
PE +qYCpP9
().execute(new HibernateCallback(){ )%1&/uN)
publicObject doInHibernate M{y|7e%K
P:vX }V |[
(Session session)throws HibernateException { k.ww-nH
Criteria criteria = gGD]t;<u
[/n'@cjNZ
detachedCriteria.getExecutableCriteria(session); _c,&\ wl$
return criteria.list(); uof0Oc.
} yl|R:/2V
}, true); PK9Qm'W b
} Pyit87h{
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public int getCountByCriteria(final T&e%/
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DetachedCriteria detachedCriteria){ gB'`I(q5.
Integer count = (Integer) @V*au:
U@MOvW)
getHibernateTemplate().execute(new HibernateCallback(){ $Jt8d|UP
publicObject doInHibernate | eK,Td%
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(Session session)throws HibernateException { a:wJ/ p
Criteria criteria = 8cequAD
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detachedCriteria.getExecutableCriteria(session); ],WwqD=
return aj+zmk~-
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criteria.setProjection(Projections.rowCount y;*My#
c lq
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()).uniqueResult(); 8VKb*
} bK6, saN>
}, true); p` ^:Q*C"
return count.intValue(); :Fq2x_IUE
} ei(|5h
} R#rh
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4ZSfz#<[z
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iFXUKGiV
用户在web层构造查询条件detachedCriteria,和可选的 4d,qXSKty
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 w`2_6[,9
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PaginationSupport的实例ps。 ~r7DEy|+
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ps.getItems()得到已分页好的结果集 >IR`]
ps.getIndexes()得到分页索引的数组 pU[a[
ps.getTotalCount()得到总结果数 t>fA!K%{
ps.getStartIndex()当前分页索引 aA!@;rR<yU
ps.getNextIndex()下一页索引 8JFnB(3xU
ps.getPreviousIndex()上一页索引 t ;bZc s
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|YMzp8Da(
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K]lb8q}Z~
#h}IUR
~`a#h#
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h/fb<jIP1
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 hPNQGVv
_%C_uBLi
一下代码重构了。 :K
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我把原本我的做法也提供出来供大家讨论吧: qhv4R| )
il 8A&`%
首先,为了实现分页查询,我封装了一个Page类: !M#?kKj
java代码: m&;zLBA;
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/*Created on 2005-4-14*/ bs4fyb
package org.flyware.util.page; woC
FN1W
mRix0XBI~
/** l[ZQ7$kL
* @author Joa !IQfeoT
* x(T!I&i={
*/ Vf#oKPP1
publicclass Page { F5om-tzy
4 @ydK
/** imply if the page has previous page */ rZwf%}
privateboolean hasPrePage; 4rGO8R
Hj-<{#,
/** imply if the page has next page */ ;RTrRh0v
privateboolean hasNextPage;
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QZz{74]n
/** the number of every page */ TWD|1
di0
privateint everyPage; 3<Pyr-z h
bRY4yT
/** the total page number */ ^+Y-=2u:
privateint totalPage; .T
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/** the number of current page */
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privateint currentPage; 9, sCJ5bb"
V8| q"UX
/** the begin index of the records by the current 3 z{5c
&,6y(-
query */ t8a@L(J$
privateint beginIndex; UH.}B3H
s|rZ>SLL
fTi{oY,zTg
/** The default constructor */ OGD8QD
public Page(){ Oujlm|
f"OA Zji
} hIg, 0B
LgD{!
/** construct the page by everyPage ?Pok-90
* @param everyPage c=U$$|qHV
* */ Q'%5"&XFD
public Page(int everyPage){ Ot8S'cB1,$
this.everyPage = everyPage; Z1MJ!{@6
} ?AM8*w
:w&)XI34
/** The whole constructor */ ~*Sbn~U
public Page(boolean hasPrePage, boolean hasNextPage, dOYm t,
o sgS?=8
DRFuvU+e
int everyPage, int totalPage, JCU3\39}
int currentPage, int beginIndex){ "gl:4|i'
this.hasPrePage = hasPrePage;
GwIfGixqH
this.hasNextPage = hasNextPage; JWm^RQ
this.everyPage = everyPage; fuIv,lDA
this.totalPage = totalPage; \Z7([G h
this.currentPage = currentPage; o\:f9JL
this.beginIndex = beginIndex; 7! A%6
} f 7QUZb\
TG%hy"k
/** VTgbJ{?
* @return V3hm*{ON
* Returns the beginIndex. Xxsnpb>
*/ #Ot*jb1
publicint getBeginIndex(){ R*TGn_J`
return beginIndex; uJ!s%s2g
} G:6$P%.
K
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/** >[P7Zlwv4
* @param beginIndex ws=9u-
* The beginIndex to set. GVHfN5bTqn
*/ +68K[s,FD
publicvoid setBeginIndex(int beginIndex){ +h vIJv ?
this.beginIndex = beginIndex; "!_
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} 94k)a8-!
{-7yZ]OO$
/** EX_sJ c
* @return ;
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* Returns the currentPage. Z!=Pc$?
*/ D A)0Y_
publicint getCurrentPage(){ bCx1g/
return currentPage; cTIwA:)D
} CTrs\G
H*
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/** +K?N:w
* @param currentPage H6 f; BS
* The currentPage to set. `J7Lecgo
*/ j?KB8oY`TP
publicvoid setCurrentPage(int currentPage){ $?J LCa
this.currentPage = currentPage; 'V9aB5O&
} E<G@LT
-$MC
/** "i<3}6/*
* @return MHT,rqG
* Returns the everyPage. w5/X{
*/ `zOAltfd
publicint getEveryPage(){ <B{VL8IA>
return everyPage; Wv*BwiQ
} $^D(%
(>5VS
/** yLIj4bf
* @param everyPage :AcNb
* The everyPage to set. VOK$;s'9}
*/ f;XsShxr
publicvoid setEveryPage(int everyPage){ \t(r@qq
this.everyPage = everyPage; a=T7w;\h
} 0}7Rm>
jl0Eg
/** r-Xe<|w
* @return l:Xf(TLa
* Returns the hasNextPage. <Ibr.L]
*/ ht)*Ync
publicboolean getHasNextPage(){ IEr`6|X
return hasNextPage; ,4T$
} a.U:B
[v`
Gv
nclnG
/** V7'x?
pt
* @param hasNextPage r~!%w(N|M
* The hasNextPage to set. pmD-]0
*/ gx9sBkoq5D
publicvoid setHasNextPage(boolean hasNextPage){ *]| JX&
this.hasNextPage = hasNextPage; .VEfd4+ni{
} <l
s/3!
M |kDys
/** Tvw2py q
* @return IV#f}NrfD
* Returns the hasPrePage. O|TwG:!
*/ lGBdQc]IL
publicboolean getHasPrePage(){ ITqigGan%
return hasPrePage; bme#G{[)Y
} <21^{ yt1
`*9FKs
/** *_rGBW
* @param hasPrePage M~Dc5\T
* The hasPrePage to set. f#Oz("d
*/ %=O!K>^vt<
publicvoid setHasPrePage(boolean hasPrePage){ 4^}PnU7z
this.hasPrePage = hasPrePage; }`FC__
} {Qmb!`F
c Yn}we}7
/** N6
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* @return Returns the totalPage. k)' z<EL6c
* CIvT5^}
*/ 7Bd_/A($
publicint getTotalPage(){ kL2sJX+
return totalPage; :+^llz
} >b](v)
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/** OL"5A18;M
* @param totalPage <l/Qf[V
* The totalPage to set. s/0FSv
x
*/ >:nJTr
publicvoid setTotalPage(int totalPage){ R:m=HS_
this.totalPage = totalPage; QD VA*6F
} DJjDKVO5t
>mSl~.I2
} #@"rp]1xv
>ZsK5v
neH"ks5
S2SQ;s-t_
Z'bMIdV
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 oDI*\S>
<rmV$_
个PageUtil,负责对Page对象进行构造: @<JQn^M
java代码: 4DM|OL`w
vrx3O
CnA)>4E*'
/*Created on 2005-4-14*/ emIbGkH
package org.flyware.util.page; Pg C]@Q%
n:)Y'52}
import org.apache.commons.logging.Log; {X"]92+
import org.apache.commons.logging.LogFactory; dg8\(G
E?o8'r
/** 1/J*ki+?
* @author Joa <bppu>&
* r:Cid*~m
*/ \1_&?(pU
publicclass PageUtil { [M>_(u6
[+7X&B
privatestaticfinal Log logger = LogFactory.getLog ~ZN9 E-uL
&g>+tkC
(PageUtil.class); hG3Lj7)UH
nE%qm -
/** <u/({SZ&
* Use the origin page to create a new page rWmi 'niu
* @param page .;6bMP[YA
* @param totalRecords .1lc'gu5y
* @return l6Bd<tSH
*/ Bn:sN_N
publicstatic Page createPage(Page page, int pz =Wq4l
xWV7#Z7
totalRecords){ G<1mj!{Vp
return createPage(page.getEveryPage(), "!?Ya{
d_B5@9e#
page.getCurrentPage(), totalRecords); W)O'( D
} 6E4 L4Vb
JwVv+9hh
/** (Cd`~*5
* the basic page utils not including exception I]1fH
/RJSkF+!
handler
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* @param everyPage JwcP[w2
* @param currentPage !1R
* @param totalRecords 4{E=wg^p
* @return page IQ8AsV&'C
*/ /9Xf[<
publicstatic Page createPage(int everyPage, int !I&Sy]G
YgDasKFm'
currentPage, int totalRecords){ z"`?<A&u
everyPage = getEveryPage(everyPage); %R>MSSjvr
currentPage = getCurrentPage(currentPage); GjBQxn
int beginIndex = getBeginIndex(everyPage, R?I3xb
VTa8.(i6v
currentPage); f#mpd]e+6
int totalPage = getTotalPage(everyPage, -XB>&dNl)T
N%yFL
totalRecords); en)DN3
boolean hasNextPage = hasNextPage(currentPage, b
L~<~gA
eyV904<F
totalPage); .jw)e!<\N
boolean hasPrePage = hasPrePage(currentPage); =Y0m;-1M
]f?LQCTq<b
returnnew Page(hasPrePage, hasNextPage, 0g\&3EvD
everyPage, totalPage, 9
|Y?#oZ1
currentPage, Mt>DAk
o}z}79Z
beginIndex); U>XGJQ<NS
} $4pW#4/4
8Qh/=Ir
privatestaticint getEveryPage(int everyPage){ [U0c
return everyPage == 0 ? 10 : everyPage; 9mZ1 a6,x
} f[D#QC
nceF4Ty
privatestaticint getCurrentPage(int currentPage){ t60m:k4J
return currentPage == 0 ? 1 : currentPage; MiRB*eA
} lvlH5Fc
%iv'/B8
privatestaticint getBeginIndex(int everyPage, int wd *Jq
E3qX$|.$/
currentPage){ ~MX@-Ff
return(currentPage - 1) * everyPage; ^y,ip=<5\3
} OoNAW<
Lif mYn[
privatestaticint getTotalPage(int everyPage, int \8!HZei
xAflcY>Ozs
totalRecords){ 'I2)-=ZL6
int totalPage = 0; IcZ 'KV
NR5A"_'
if(totalRecords % everyPage == 0) +nuQC{^>
totalPage = totalRecords / everyPage; V<7Gd8rDMM
else Df9}YI;?
totalPage = totalRecords / everyPage + 1 ; !p$V7pFu6
Yu=^`I
return totalPage; {ig@Iy~DT
} |j<'[gB\p
]F~5l?4u#
privatestaticboolean hasPrePage(int currentPage){ #*~Uu.T
return currentPage == 1 ? false : true; \Ip<bbB0
} -h}J%UV
[*(MI 9WM
privatestaticboolean hasNextPage(int currentPage, V*N9D>C
FYJB.lAT
int totalPage){ '"EOLr\Z,
return currentPage == totalPage || totalPage == *HRRv.iQ
lMP7o&
0 ? false : true; F-6*
BUqJ
} ;S7xJ'H
ntT|G0E
Q.Acmht#
} T-\,r
gM8 eO-d
c8u0\X,
>,v~,<3
i
Am0$U eSZ
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 T]xGE
=% p"oj]:
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 M\%{!Wzo8
ocMf}"
做法如下: ,#A,+!4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ) E\pQ5&
VXa]L4jJ9
的信息,和一个结果集List: 1#V0g Q
java代码: B.|vmq,u
d3\8BKp
I.>LG
/*Created on 2005-6-13*/ 1L0ku@%t9Y
package com.adt.bo; nF-FoO98
M3''xrpC
import java.util.List; |lv4X}H
>@X=E3
import org.flyware.util.page.Page; 1;h>^NOq
l@Ki`if
/** YW5E
| z
* @author Joa QqDF_
*/ xqr`T0!&
publicclass Result { 9T]]T Ev4
\S9z.!7v$
private Page page; #O~Y[''C5X
5q<kt{06\
private List content; JsC0^A;fM
*,. {Xf
/** 4Vs;Y&t]
* The default constructor y|aWUX/a
*/ yD KX,
public Result(){ L=$P
super(); fkYQ3d,`
} L \$zr,=C
|!|`Je3 K
/** 0K!9MDT}*
* The constructor using fields yP-Dj
,
* I}:/v$btM
* @param page *n47.(a2i
* @param content 9.R_=
*/
`>*P(yIN
public Result(Page page, List content){ M_e!s}F
this.page = page; pxN'E;P-
this.content = content; P$Dr6;
} qHj4`&
c*h5lM'n6
/** ,kP{3.#Q
* @return Returns the content. ^\!^#rO
*/ RHxd6Gs"
publicList getContent(){ 1~*_H_Q't
return content; r}991O<
} xP*R H-<
RsbrD8*AD
/** vw3W:TL
* @return Returns the page. 2|cIu ' U
*/ >[p+L='
public Page getPage(){ *-n$n
return page; [`&cA#C9Yp
} >A)he!I
ua{eri[
/** Ze~\=X" "
* @param content E )PEKWK\
* The content to set. ^O?$}sr
*/ 5t PmrWZ
public void setContent(List content){ #qPk ,a
this.content = content; .B)v "Sw#
} ":Q70*xSm
UeRenp
/** s"'1|^od
* @param page 7yc:=^ )
* The page to set. ?]})Xf.A
*/ [AU1JO`\"
publicvoid setPage(Page page){ X2{3I\'Ft
this.page = page; Q=dR[t>^
} l`1ZS8 [.
} \h
yTcFb
'
Sl9xd
E>ev /6ox
g5cR.]oz
7fVVU+y
2. 编写业务逻辑接口,并实现它(UserManager, oU2RxK->u
/eE P^)h
UserManagerImpl) cx$Oh`-Car
java代码: Fm@GU
-uh/W=Q1R
Op|Be
/*Created on 2005-7-15*/ BG|Kw)z*KM
package com.adt.service; \/5 8#
PCES&|*rf
import net.sf.hibernate.HibernateException; =#W{&Te;
EH[ ?*>+s
import org.flyware.util.page.Page; ,Pl[SMt!
1rN&Y,61\
import com.adt.bo.Result; 7#RW4ZM
,^'Y7"
/** \UiuJ+
* @author Joa H: U_k68
*/ "XH]B
publicinterface UserManager { TEYbB=.
gC'GZi^
public Result listUser(Page page)throws >
4^U=T#
xv)7-jlx
HibernateException; !is8`8F8
WgY3g1C
} n"Ev25%
?6[>HX;
s2tEyR+gW
]\GGC]:\@
]s u\[?l
java代码: ^awl-CG
f5O*Njl
Z8:iaP)
/*Created on 2005-7-15*/ `=.{i}V
package com.adt.service.impl; `aC#s3[
jW6@U%[!b
import java.util.List; wOOPuCw?
kt@+UK."
import net.sf.hibernate.HibernateException; h rZ\ O?j
:]]amziP&
import org.flyware.util.page.Page; $k!t&G
import org.flyware.util.page.PageUtil; vzVl2
6h5*b8LxA
import com.adt.bo.Result; *zmbo >{(
import com.adt.dao.UserDAO; 2;q6~Y,
import com.adt.exception.ObjectNotFoundException; ]2(
%^#qBG
import com.adt.service.UserManager; l\S..B
+
c~>M7e(
/** rVz#;d!`z
* @author Joa %7{6>6%
*/ L5>>gG,
publicclass UserManagerImpl implements UserManager { 2\7]EW
Gjzhgz--
private UserDAO userDAO; 7igrRU#1%
{yJ{DU?%Y
/** amPQU
* @param userDAO The userDAO to set. upX/fLc
*/ Sd{>(YWx~
publicvoid setUserDAO(UserDAO userDAO){ l5aQDkp}
this.userDAO = userDAO; =7$YBCuF
} F[J;u/Z
,,i;6q_f
/* (non-Javadoc) WjA)0HL(
* @see com.adt.service.UserManager#listUser b]J_R"}
(5atU |8r
(org.flyware.util.page.Page)
LDbo
*/ ]ao]?=q C
public Result listUser(Page page)throws \ii^F?+b
((H}d?^AJ
HibernateException, ObjectNotFoundException { 5:YtBdP
int totalRecords = userDAO.getUserCount(); H
>RGX#|
if(totalRecords == 0) JNZKzyJ9K
throw new ObjectNotFoundException XX/cJp
{gJOc,U4b
("userNotExist"); d`2VbZC`
page = PageUtil.createPage(page, totalRecords); %T88K}?=
List users = userDAO.getUserByPage(page); C=.
returnnew Result(page, users); bd%/dr
} z/;NoQ-
Qx
{/izc
} ptUnV3h
W/+|dN{O+g
NjMo"1d
7^:s/xHO*
or(Z-8a_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 0C0iAp
BB~Qs
询,接下来编写UserDAO的代码: Ha;^U/0|
3. UserDAO 和 UserDAOImpl: 73P(oVj<
java代码: YRB,jwne
9=h A#t.#
MF=@PE][
/*Created on 2005-7-15*/ $rf5\_G,96
package com.adt.dao; ==c\* o
l'$AmuGj
import java.util.List; Bm^vKzp
{y :/9
import org.flyware.util.page.Page; 7|H !( a'
2&P'rmFm
import net.sf.hibernate.HibernateException; fLPB *y6
3:S
Ex;d+
/** |3vQmd !2}
* @author Joa ;o#dmG
*/ (2<0kqj%
publicinterface UserDAO extends BaseDAO { =:5yRP
m,Os$>{Ok
publicList getUserByName(String name)throws Z!tt(y\
rjfQ\W;}U
HibernateException; x@Q}sW92
0gxbo
publicint getUserCount()throws HibernateException; ?e yo2:-$
17J|g.]m-&
publicList getUserByPage(Page page)throws Kh3*\x T
yl)}1DPP
HibernateException; ~,dj)x
3M
IaN|S|n~
} C
<]rY
0;o`7f
(%\N-[yZ
eBG7]u,Q
2v yB[(
java代码: iv\?TAZC
*h$Dh5%P
.~C*7_
/*Created on 2005-7-15*/ c7S<ex,
package com.adt.dao.impl; f |aO9w
OyFBM>6gh
import java.util.List; ^-mz!{
=|=9\3po
import org.flyware.util.page.Page; 8!E$0^)c|
8%2*RKj
import net.sf.hibernate.HibernateException; pX|\J>u)
import net.sf.hibernate.Query; 6i, d|
6Kg
lp\2
import com.adt.dao.UserDAO; ;PGC9v%i
F5:4 B]ZF
/** iC$~v#2
* @author Joa hG; NJx-=R
*/ NSj}?hz
public class UserDAOImpl extends BaseDAOHibernateImpl g,mcxXO
~%(r47n
implements UserDAO { 61b,+'-
;OE{&
/* (non-Javadoc) 8gr&{-5
* @see com.adt.dao.UserDAO#getUserByName 5fM/y3QPsZ
}8 fG+H.
(java.lang.String) ]MRE^Je\h
*/ U*1rA/"n
publicList getUserByName(String name)throws U3az\E)HV
8Q?)L4.]
HibernateException { G23Mr9m5O
String querySentence = "FROM user in class (\>_{"*=
0}-&v+
com.adt.po.User WHERE user.name=:name"; lD.PNwM
Query query = getSession().createQuery &KX|gB'
vD^^0-Pk6
(querySentence); 5fSDdaO
query.setParameter("name", name); 6D6=5!l
return query.list(); ?}bSQ)b
} WUMx:a0!
x]J{EA{+
/* (non-Javadoc) XBdC/DM[
* @see com.adt.dao.UserDAO#getUserCount() o~ 2bk<]z
*/ +.mIC:9
publicint getUserCount()throws HibernateException { fw'$HV76
int count = 0; NhS0D=v6
String querySentence = "SELECT count(*) FROM L*Xn!d%
m},nKsO
user in class com.adt.po.User"; v6;XxBR6
Query query = getSession().createQuery e#)}.
`N;u#z
(querySentence); 0q>f x
count = ((Integer)query.iterate().next ;Hv#SRSz
/<Zy-+3
()).intValue(); ` L6H2:pf
return count; uFW4A
} n +`( R]Q
Vt*Duh+4
/* (non-Javadoc) t? yMuK
* @see com.adt.dao.UserDAO#getUserByPage $BwWhR
lT DF5.aE
(org.flyware.util.page.Page) E_/v$
*/ hnmFhJ !g
publicList getUserByPage(Page page)throws Fu(e4E
\/. Of]YQ
HibernateException { 4cTJ$" v
String querySentence = "FROM user in class m{I_E
G
`9kjYSd#E
com.adt.po.User"; 7a->"W
Query query = getSession().createQuery >/ECLP
'h([Y8p{
(querySentence); {y)s85:t
query.setFirstResult(page.getBeginIndex()) !D7[R'RgY
.setMaxResults(page.getEveryPage()); gh['T,
return query.list(); x{&0:|bCs6
} A|c :&i
U"<Z^)
} Bz }Kdyur
hSQP
'6
gPd:>$
hJrxb<9@Y0
P5%DvZB$w
至此,一个完整的分页程序完成。前台的只需要调用 \"<&8
P (_:8|E
userManager.listUser(page)即可得到一个Page对象和结果集对象 NV^ktln
(IAl$IP63s
的综合体,而传入的参数page对象则可以由前台传入,如果用 h,\^Sb5AP
pIqPIuy
webwork,甚至可以直接在配置文件中指定。 VQ$=F8ivG
mdoy1a
下面给出一个webwork调用示例: \4bma<~a
java代码: 0 jVuFl
0/#XUX 4
"mSDL:$
/*Created on 2005-6-17*/ d&n0:xOc
package com.adt.action.user; +[zrU`!@
{Ejv8UdA9
import java.util.List; !3-mPG<
]
Cc1sZWvz
import org.apache.commons.logging.Log; Z=L' [6
import org.apache.commons.logging.LogFactory; 49@
pA-
import org.flyware.util.page.Page; UFyGp>/06
_r+9S.z
import com.adt.bo.Result; v}M, M&?
import com.adt.service.UserService; G$xuHHZ'
import com.opensymphony.xwork.Action; ?MPM@9
(t&P.N/
/** /#G^?2oM
* @author Joa +7|Oy3s
*/ BO#fzq%
publicclass ListUser implementsAction{ CDO_A \
MVe5j+8
privatestaticfinal Log logger = LogFactory.getLog q}M^i7IE
C'
o4Su#
(ListUser.class); VVYQIR]!yk
q@8Rlc&
private UserService userService; TXH: + m c
i6h:%n]Io
private Page page; 3r%I *
/ d0LD
privateList users; ahhVl=9/ao
Rl=NVo
/* 49
fs$wr@
* (non-Javadoc) <Lyz7R6
* |*Z'WUv
* @see com.opensymphony.xwork.Action#execute() _U.8\J2
*/ +VAfT\G2
publicString execute()throwsException{ *,_Qdr^F
Result result = userService.listUser(page); oYup*@t
page = result.getPage(); %_@8f|# ,M
users = result.getContent(); Y=vA;BE]R
return SUCCESS; 0Dc$nL?TqX
} WLDt5R
)d>"K`3
/** >Djv8 0
* @return Returns the page. sq@Eu>Ng(X
*/ 5\S)8j `8
public Page getPage(){ <$Q&n{
return page; .Uh-Wi[
} w44{~[0d4
E IsA2 f
/** S;Lqx5Cd
* @return Returns the users. fdck/|`t
*/ xPq3Sfg`A
publicList getUsers(){ ''?.6r
return users; ~N>[7I"*
} %Kw5b ;
?N,a {#w
/** 2a (w7/W:
* @param page mu=u!by.E
* The page to set. o-("S|A-
*/ Lyt6DvAp"
publicvoid setPage(Page page){ XFG]%y=/6
this.page = page; KynQ<I/
} 8W[QV
:1hp_XfJb
/** -x:Wp*,
* @param users zOg#=ql
* The users to set. `5O<U~'d
*/ z]gxkol\
publicvoid setUsers(List users){ P-7!\[];te
this.users = users; wAF>C[ <\
} 96}/;e]@
`w[0q?}"`
/** FGy7KVR
* @param userService AWh{dM
* The userService to set. 8{4I6;e-
*/ xZGR<+t
publicvoid setUserService(UserService userService){ 6X7r=w
this.userService = userService; }{bO~L7
} PcM:0(,G
} n!ea)+^
r1}7Q7-z
u32wS$*8
44kY[jhf
lY?TF
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 1YAy\F~`.
k3sP,opacX
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ?rk3oa-
unSF;S<
么只需要: Q\m"n^XN
java代码: 5NJ@mm{0
>J.a,!
wW6?.}2zU
<?xml version="1.0"?> vkc(-n
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork HR['y9U
qf4|!UR{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &7E 0H{
MCz+l0
1.0.dtd"> 8%arA"#S
\8ulX>]
<xwork> xotq$r
M}(4>W
<package name="user" extends="webwork- QTcngv[
R?Iv<(I
interceptors"> $v-lG(
&fiDmUxj
<!-- The default interceptor stack name 4y>G6TD^
a9FlzR
-->
[GU!],Y
<default-interceptor-ref qe`W~a9x
*v8Cj(69
name="myDefaultWebStack"/> .zBSjh_=H
:bLGDEC
<action name="listUser" Da?0B9'
k(u W( 6
class="com.adt.action.user.ListUser"> {;f`t3D
<param @B7;
_ky!4^B
name="page.everyPage">10</param> 0kmVP~K
<result 5C#&vYnq
]2h~Db=
name="success">/user/user_list.jsp</result> H# 2'\0u
</action> 6CY_8/:zL
"N7C7`izc
</package> n;v8Vc'
-']#5p l
</xwork> h8pc<t\6
hCW8(Zt
@ mtv2P`
B quyPG"
B:^5W{
{BJ[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 dRWp/3 }
$sGX%u
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 F'pD_d9]e
34s:|w6y
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 N@tzYD|hA
/vsQ <t;~
J*a`qU
`=q)-y_C
+SUQRDF@i
我写的一个用于分页的类,用了泛型了,hoho Yw?%>L
JfKl=vg
java代码: D'uzH|z8
sx`C<c~u
WXO@oZ!
package com.intokr.util; zcIZJVYA
r4!zA-{
import java.util.List; ,h8)5Mj/J
o#%2N+w
/** 2MtaOG2l&q
* 用于分页的类<br> -qid.
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 'hU&$lgMF
* a l#yc
* @version 0.01 Rjm5{aa-
* @author cheng t)$>++i
*/ ;<ed1%Le,
public class Paginator<E> { oVc_(NH-
privateint count = 0; // 总记录数 L.+5`&
privateint p = 1; // 页编号 K
V 4>(
privateint num = 20; // 每页的记录数 ro^Y$;G
privateList<E> results = null; // 结果 bG2!5m4L
7v%~^l7:x
/** ~q-|cl<
* 结果总数 W9a H]9b
*/ &W".fRH_O
publicint getCount(){ TO3Yz3+A
return count; cJi5\<b
} //V?rs
(nvSB}?
publicvoid setCount(int count){ G^)|c<'M
this.count = count;
<&$!;d8
} ^XZmtB
Q8z>0ci3o
/** B1*%pjy
* 本结果所在的页码,从1开始 "xnek8F
* a&PoUwG
* @return Returns the pageNo. (Ozb +W?
*/ L7a+ #mGE
publicint getP(){ E$smr\
return p; Oyj!N`&z@
} 2\EMtR>.M'
[S3X
/** Fv#ToT:QXe
* if(p<=0) p=1 {%UY1n
* (_U&EX%
* @param p ?z
Ms;
*/ `9b D%M
publicvoid setP(int p){ <(s+
if(p <= 0) s{<rc>
p = 1; MEq
()}7P
this.p = p; 0D$+WX
} NZdQz
{PYN3\N,
/** 64b9.5Bn
* 每页记录数量 4y%N(^
*/ mxP{"6
publicint getNum(){ vV"TTzs!
return num; r&Za*TD^
} @f{)]I +f
[4t_ 83
/** f[h=>O
* if(num<1) num=1 =We}&80x
*/ n#Z6 d`
publicvoid setNum(int num){ U/|B IF
if(num < 1) MJ&6 Z*
num = 1; ?Mji'ZW}
this.num = num; F!^ Y!Y@H
} j G{xFz>x
s^3t18m&1
/** o` ,&yq.
* 获得总页数 f>Bcr9]]
*/ {*>$LlL
publicint getPageNum(){ ]'2p"A0U
return(count - 1) / num + 1; .+{nfmc,c
} v2rX uo
|wVoJO!O}
/** UI>-5,X
* 获得本页的开始编号,为 (p-1)*num+1 %oC]Rpdu
*/ \=,+weGw@
publicint getStart(){ B^{bXhDp
return(p - 1) * num + 1; v |QFUa`
} Tje =vI
VY~WkSi[<
/** 4lvo9R
* @return Returns the results. }_5z(7}3
*/ ^>[DG]g
publicList<E> getResults(){ q&
4Z.(
return results; *R1x^t+)
} !>9*$E
|
*"j_3vAx
public void setResults(List<E> results){ G0y%_"[
this.results = results; B^$l]cvZ
} ?#slg8[
v%86JUlK.
public String toString(){ +z("'Cv
StringBuilder buff = new StringBuilder P,D >gxl
*w>
/vu
(); 5\EHu8
buff.append("{"); 'HW(RC0dR
buff.append("count:").append(count); e`#Gq0}8
buff.append(",p:").append(p); nV"[WngN
buff.append(",nump:").append(num); >\(Ma3S
buff.append(",results:").append p*NC nD*
p~Dm3^Y
(results); *b7HtUA
buff.append("}"); #BlH)Cv
return buff.toString(); @YWfq$23
} otX#}} +
MH{vFA4:,
} mj5A*%"W
D1#E&4
((;9%F:/$