Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _E eH
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pEk^;
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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 /(C?3}}L
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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 9"Vch;U$
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分页支持类: !mNXPqnN
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java代码: 9"mOjL
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package com.javaeye.common.util; f8`K8Y]4
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import java.util.List; x)eYqH~i
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publicclass PaginationSupport { Uc,D&Og
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publicfinalstaticint PAGESIZE = 30; s%h|>l[lKT
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privateint pageSize = PAGESIZE; P7GuFn/p~2
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privateList items; q)%F#g
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privateint totalCount; j^ L"l;m
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privateint[] indexes = newint[0]; E$5)]<p! <
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privateint startIndex = 0; |J:n'}
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public PaginationSupport(List items, int M@$}Og
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totalCount){ om%L>zfB
setPageSize(PAGESIZE); );T0n
setTotalCount(totalCount); C^ngdba\
setItems(items); \l^L?69
setStartIndex(0); ,lK=m~
} z3!j>X_w
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public PaginationSupport(List items, int VwfeaDJw
^):m^w.
totalCount, int startIndex){ r':wq
setPageSize(PAGESIZE); gycjIy@t
setTotalCount(totalCount); W}&[p=PAS
setItems(items); 6"@+Jz
setStartIndex(startIndex); 0* Ox>O>
} EBjSK/
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public PaginationSupport(List items, int O;RsYs9
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totalCount, int pageSize, int startIndex){ [J0f:&7\
setPageSize(pageSize); @<]sW*s
setTotalCount(totalCount); j#^EZ/
setItems(items); H;('h#=cD
setStartIndex(startIndex); kev|AU (WX
} 6H+'ezM
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publicList getItems(){ RTN?[`
return items; l1 (6*+
} 0vN <0
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publicvoid setItems(List items){ o+UCu`7e
this.items = items; +O`3eP`u
} <a9<rF =r
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publicint getPageSize(){ }j=UO*|
return pageSize; &)UZ9r`z
} oNW.-gNT
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publicvoid setPageSize(int pageSize){ O@*7O~eO
this.pageSize = pageSize; V_b"^911r
} "B18|#v
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publicint getTotalCount(){ RmF,x9
return totalCount; \G}02h
} +NML>g#F~z
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publicvoid setTotalCount(int totalCount){ JbT+w\o
if(totalCount > 0){ #2*l"3.$.R
this.totalCount = totalCount; P2HR4`c
int count = totalCount / CPJ8G}4
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pageSize; Swugt"`nN
if(totalCount % pageSize > 0) f
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count++; m]C|8b7Y
indexes = newint[count]; 6T-h("t
for(int i = 0; i < count; i++){ X`/3X}<$7
indexes = pageSize * [bE-Uu7q5P
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} .3xpDVW^e
}else{ UoDS)(i
this.totalCount = 0; A0mj!P 9
} ;E,^bt<U
} G$#Q:]N
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publicint[] getIndexes(){ _=%F6}TE
return indexes; 4:umD*d 3E
} hw2'.}B"(
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publicvoid setIndexes(int[] indexes){ 0tA~Y26
this.indexes = indexes; ?vA)F)MS
} @#HB6B
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publicint getStartIndex(){ uD'yzR!]+
return startIndex; .bdp=vbA
} irjOGn
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publicvoid setStartIndex(int startIndex){ !H)$_d \uj
if(totalCount <= 0) n ~c<[
this.startIndex = 0; E[Xqyp!<
elseif(startIndex >= totalCount) 0.pZlv
this.startIndex = indexes SB1j$6]OR7
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[indexes.length - 1]; j-~x==c-;
elseif(startIndex < 0) }j+Af["W?
this.startIndex = 0; e>F i
else{ g`7C1&U*T
this.startIndex = indexes ,W8EU
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9
[startIndex / pageSize]; B#Q` !B4v
} ar&j1""
} }-Ds%L
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publicint getNextIndex(){ "Wz8f
int nextIndex = getStartIndex() + n>t&l8g%g
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pageSize; q fc:%ks2
if(nextIndex >= totalCount) ye<b`bL2.
return getStartIndex(); GtuA94=!V&
else `!Z0;qk
return nextIndex; Fb2,2Px
} 3!l+)g
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publicint getPreviousIndex(){ +N6IdDN3
int previousIndex = getStartIndex() - `}r)0,Z}3
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pageSize; 5taR[ukM
if(previousIndex < 0) %*}h{n
return0; h+gaKh=k+
else *|gY7Av*
return previousIndex; HbI'n,+
} 7`s*
{
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} us5<18M5
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抽象业务类 '2S/FOb
java代码: (HEi;
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/** d/8p?Km
* Created on 2005-7-12 "|Ke/0rGB
*/ f};RtRo2
package com.javaeye.common.business; o5@d1A
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import java.io.Serializable; bcR";cE
import java.util.List; adcH3rV
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import org.hibernate.Criteria; B_uhNLd
import org.hibernate.HibernateException; /~(T[\E<
import org.hibernate.Session; J9%I&lu/
import org.hibernate.criterion.DetachedCriteria; {xD\w^
import org.hibernate.criterion.Projections; A=Y A #0
import ;tJ}*!z
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org.springframework.orm.hibernate3.HibernateCallback; QO/nUl0E
import Iq0[Kd0.j
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org.springframework.orm.hibernate3.support.HibernateDaoS 3jqV/w[-
#0"Pd8@
upport; e**<et.
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:
import com.javaeye.common.util.PaginationSupport; \y(ZeNs
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public abstract class AbstractManager extends *@VS^JB
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HibernateDaoSupport { B,q)<z6<
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privateboolean cacheQueries = false; ]Sey|/@D
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privateString queryCacheRegion; hS 9^Bi
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publicvoid setCacheQueries(boolean zH13~\
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cacheQueries){ 2@6Qifxd@
this.cacheQueries = cacheQueries; Ueu~803~
} qOTo p-
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publicvoid setQueryCacheRegion(String j0b>n#e7
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queryCacheRegion){ 8U%y[2sT
this.queryCacheRegion = +h)1NX;o1
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queryCacheRegion; ae#Qeow`
} X:/7#fcG8
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publicvoid save(finalObject entity){ jK]An;l{Z
getHibernateTemplate().save(entity); p[K!.vOt+
} tZ.hSDH
=E$B0^_2RC
publicvoid persist(finalObject entity){ NY
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getHibernateTemplate().save(entity); m;JB=MZ=m
} V"|`Z}XW
@iU(4eX
publicvoid update(finalObject entity){ ^H!45ph?Jc
getHibernateTemplate().update(entity); qoP/`Y6
} ]i/Bq!d l
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publicvoid delete(finalObject entity){ Zet80|q
getHibernateTemplate().delete(entity); vd[?73:C
} Y<t(m$s
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publicObject load(finalClass entity, 5K,=S
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finalSerializable id){ O9*l6^Scw
return getHibernateTemplate().load sE])EwZ
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(entity, id); 6VtN4c.Q
} )&$mFwf
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publicObject get(finalClass entity, g_JSgH!4
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finalSerializable id){ [7\x(W-:@>
return getHibernateTemplate().get Mt*V-`+\
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(entity, id); _/J`v`}G
} 3=("vR`!
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publicList findAll(finalClass entity){ R:`)*=rL%
return getHibernateTemplate().find("from +xuj ]J
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" + entity.getName()); e0M'\'J
} @Hl+]arUh
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publicList findByNamedQuery(finalString P}"T3u\N
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namedQuery){ E5IS<.
return getHibernateTemplate 61}eB/;7
tpa<)\7KJ
().findByNamedQuery(namedQuery); XG E.*aI
} :W9a t
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publicList findByNamedQuery(finalString query, Dqc2;>
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finalObject parameter){ t[/APm-k~>
return getHibernateTemplate >uxAti\
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().findByNamedQuery(query, parameter); !ou;yE&<,
} tC5>K9Ed
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publicList findByNamedQuery(finalString query, 4N5\sdi
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finalObject[] parameters){ Fd#Zu.Np
return getHibernateTemplate AYAbq}'Yt
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().findByNamedQuery(query, parameters); mRy0zN>?
} ,hWuAu6.L
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publicList find(finalString query){ }S;A%gYm
return getHibernateTemplate().find w3&L 6|,
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(query); |_hIl(6F5N
} tF6-@T\6
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publicList find(finalString query, finalObject abp\Ih^b
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parameter){ P5W58WxT'
return getHibernateTemplate().find ^mouWw)a_
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(query, parameter); ?KWo1
} @p@b6iLpO
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public PaginationSupport findPageByCriteria "8Lv
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(final DetachedCriteria detachedCriteria){ +i[vJRLxl~
return findPageByCriteria (|pM^+
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); nG-DtG^z
} Lf`<4 P
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public PaginationSupport findPageByCriteria SX&Q5:
eCiI=HcW;
(final DetachedCriteria detachedCriteria, finalint gfKv$~
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startIndex){ i7e_~K
return findPageByCriteria ltKMvGEF
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(detachedCriteria, PaginationSupport.PAGESIZE, _j*a5fsPU
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startIndex); i0Rj;E=:]
} $&&+2?cx0
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public PaginationSupport findPageByCriteria bwa*|{R
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(final DetachedCriteria detachedCriteria, finalint i1K$~
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pageSize, !JBj%| !
finalint startIndex){ u'^kpr`y
return(PaginationSupport) d5`D[,]d
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getHibernateTemplate().execute(new HibernateCallback(){ S|fb'
publicObject doInHibernate biS{.
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(Session session)throws HibernateException { Ko)f:=Qo
Criteria criteria = FF;Fo}no-
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detachedCriteria.getExecutableCriteria(session); 5vLA)Al3
int totalCount = Y[W :Zhl;
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((Integer) criteria.setProjection(Projections.rowCount RRQIlI<
nTD4^'
()).uniqueResult()).intValue(); 57q?:M=^
criteria.setProjection 8c>xgFWp9
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(null); S~R[*Gk_uT
List items = 7-0j8$`
g+7j?vC{'
criteria.setFirstResult(startIndex).setMaxResults y;(G%s1
P#V}l'j(<a
(pageSize).list(); lPrAx0m13%
PaginationSupport ps = >x6)AH.
5tk7H2K^<
new PaginationSupport(items, totalCount, pageSize, *!j!o%MB
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startIndex); skU
}BUK6
return ps; ]u:_r)T
} C=IN "
}, true); s< Fp17
} ,LC(Ax'.F
@2On`~C`
public List findAllByCriteria(final `Y^l.%AZZ
%
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DetachedCriteria detachedCriteria){ dn:\V?9
return(List) getHibernateTemplate K=r~+4F
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().execute(new HibernateCallback(){ uKj(=Rqq
publicObject doInHibernate KzJJ@D*4M]
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(Session session)throws HibernateException { /`0>U
Criteria criteria = >UV}^OO
RS#C4NG
detachedCriteria.getExecutableCriteria(session); 3sW!ya-VZ
return criteria.list(); bnPhhsR
} "{trK?-8%
}, true); 18p4]:L
} ,`YIcrya:
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public int getCountByCriteria(final Ypxp4B
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DetachedCriteria detachedCriteria){ uy<<m"cA;
Integer count = (Integer) @%YbptT}
{;6a_L@q;|
getHibernateTemplate().execute(new HibernateCallback(){ ;}M&fXFp"|
publicObject doInHibernate Z[0/x.pp$
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(Session session)throws HibernateException { ( uG;Q
Criteria criteria = m&z(2yb1
'=eVem=
detachedCriteria.getExecutableCriteria(session); fJ6Q:7
return $*LBZcL
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criteria.setProjection(Projections.rowCount j)#yyK{k2s
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()).uniqueResult(); 6urU[t1
} 6'.)z,ts
}, true); E25w^x2
return count.intValue(); P,(_y8
} g++-v HD
} EEo I|
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用户在web层构造查询条件detachedCriteria,和可选的 l ?YO!$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7\ZSXQy1W
g_A#WQyh\'
PaginationSupport的实例ps。 ) jt?X}
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ps.getItems()得到已分页好的结果集 TP~1-(M)}
ps.getIndexes()得到分页索引的数组 FvO,* r9
ps.getTotalCount()得到总结果数 Oi]B%Uxy=
ps.getStartIndex()当前分页索引 Jr= fc*f
ps.getNextIndex()下一页索引 [LUqF?K&
ps.getPreviousIndex()上一页索引 T LF'7ufq
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 t* p%!xsH
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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 A)Rh
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一下代码重构了。 N R4\TU
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我把原本我的做法也提供出来供大家讨论吧: CS5[E-%}T=
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首先,为了实现分页查询,我封装了一个Page类: _OS,zZ0
java代码: [7g-M/jvY
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/*Created on 2005-4-14*/ W-Vc6cq
package org.flyware.util.page; K5t.OAA:
E7_OI7C
/** Zb|a\z8 ?
* @author Joa Mn<s9ITS-
* @`8a3sL)
*/ ?Zk;NL9
publicclass Page { Q#.E-\=^
jA[")RVG
/** imply if the page has previous page */ {,Rlq
privateboolean hasPrePage; JAI.NKB3
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/** imply if the page has next page */ GCX?W`
privateboolean hasNextPage; JNJ6HyCU
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/** the number of every page */ wO`G_!W9
privateint everyPage; rk@qcQR
8V9OMOt!
/** the total page number */ =dQ/^C_hj
privateint totalPage; 4\g[&
;DVg[#
/** the number of current page */ :^xNHMp!
privateint currentPage; N:S2X+}(
$|TLt{ K
/** the begin index of the records by the current 6Z2|j~
9_e_Ne`i`?
query */ 3(vm'r&5n>
privateint beginIndex; ='_3qn.
s.n:;8RibP
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/** The default constructor */ ir>+p>s.
public Page(){ |F<%gJ
vts"
} c': 4e)
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/** construct the page by everyPage <RY!Mc
* @param everyPage v&3"(fp
* */ (I'{
pF)
public Page(int everyPage){ 25 :v c0
this.everyPage = everyPage; n%iL+I
} `D$^SHfyz
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/** The whole constructor */ 2;3&&yK2b
public Page(boolean hasPrePage, boolean hasNextPage, W- nS{v(
fwMYEj
G ;ZN>8NB
int everyPage, int totalPage, RAws{<6T-
int currentPage, int beginIndex){ }[MkJ21!
this.hasPrePage = hasPrePage; csxn"Dz\
this.hasNextPage = hasNextPage; .tyV=B:h
this.everyPage = everyPage; </?ef&
this.totalPage = totalPage; *M0O&" ~j
this.currentPage = currentPage; `P-d. M6Oa
this.beginIndex = beginIndex; W1t_P&i
} F:[[@~z
]` A*7
/** VM\\.L
* @return 0Zo><=
* Returns the beginIndex. *yo'Nqu
*/ -yg;,nCg
publicint getBeginIndex(){ yOvV"x]
return beginIndex; DIWyv-
} ,j\uvi(Y
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/** ~ b66
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* @param beginIndex qLc&.O.=
* The beginIndex to set. BI<9xl]a
*/ F$kiSjh9aJ
publicvoid setBeginIndex(int beginIndex){ 8}4.x3uw
this.beginIndex = beginIndex; rd$T6!I
} GC3d7
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/** GK6CnSV8d
* @return JP
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* Returns the currentPage. jUR*
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*/ $ndBT+i
publicint getCurrentPage(){ ]Y76~!N
return currentPage; z7)$m0',?
} gm8JxhL
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/** E?|NYu#I6
* @param currentPage WX_g
* The currentPage to set. "{H{-`Ni
*/ (b&Z\?"
publicvoid setCurrentPage(int currentPage){ W[]|Uu/%
this.currentPage = currentPage; [fb9;,x`
} O#C0~U]dDW
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/** @Gw]cm
* @return 6"}F
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* Returns the everyPage. EM+! ph
*/ 0b8=94a{>
publicint getEveryPage(){ /Dt:4{aTOC
return everyPage; Pc5C*{C
} |E||e10wR
uGW#z_{(n
/** B>\q!dX3
* @param everyPage 0o BAJP
* The everyPage to set. DW :\6k
*/ [eTEK W]
publicvoid setEveryPage(int everyPage){ o8%o68py
this.everyPage = everyPage; MTgf.
} [z=!OFdE
tI#65ox#
/** g/P1lQ)
* @return *`/4KMrq
* Returns the hasNextPage. {Dy,|}7s
*/ Az#kE.8b*A
publicboolean getHasNextPage(){ -;qK_x
return hasNextPage; p-rQ'e
} [C~N#S[]
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/** VsK8 :[Al
* @param hasNextPage $kMe8F_
* The hasNextPage to set. m]
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*/ ~HT:BO$
publicvoid setHasNextPage(boolean hasNextPage){ %(POC=b#[
this.hasNextPage = hasNextPage; a[sdYZ
} S==0/
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/** $-!7<a-
* @return hjk]?MC
* Returns the hasPrePage. s=E6HP@q
*/ vMn$lT@
publicboolean getHasPrePage(){ SNSoV3|k-
return hasPrePage; 00y(E@~
} ^(7l!
rd[mC[
r
/** ]; g~)z
* @param hasPrePage QqBQ[<_
* The hasPrePage to set. <pS#wTsN4%
*/ @$$J}~{
publicvoid setHasPrePage(boolean hasPrePage){ gf4Hq&Rf
this.hasPrePage = hasPrePage; qvhG^b0h
} Ep')@7^n
$`t2SD
/** /;21?o
* @return Returns the totalPage. &f?JtpB
* NxK.q)tj6
*/ rfSEL
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publicint getTotalPage(){ 29|nt1Z
return totalPage; %P#|
}
} a8k`Wog
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/** K!E\v4
* @param totalPage p_apVm\t_
* The totalPage to set. f6Y-ss;'
*/ F%%mcmHD#
publicvoid setTotalPage(int totalPage){ wZ`{ i
this.totalPage = totalPage; pXh`o20I
} I!K-*
AB
aSHN*tP%y
} 3(.Y>er%U
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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 @KZW*-"
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个PageUtil,负责对Page对象进行构造: 07ppq?,y
java代码: %6M%PR~u
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/*Created on 2005-4-14*/ 8hyXHe
package org.flyware.util.page; XZ(<Mo\v
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import org.apache.commons.logging.Log; Z*NTF:6c
import org.apache.commons.logging.LogFactory; Hf30ve}
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/** tBsvi%F
* @author Joa hW;n^\lF#e
* mOLz(0
*/ M$6;&T
publicclass PageUtil { B LZ<"npn
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privatestaticfinal Log logger = LogFactory.getLog F^}d>2W(
L}g#h+GP[
(PageUtil.class); wW<u)|>ye
, BZ(-M
/** 0+e0<'
* Use the origin page to create a new page 2:yXeSeA
* @param page X1V~.kvt)
* @param totalRecords hOdU%
* @return 2G3Hi;q18
*/ ^R7X!tOq4
publicstatic Page createPage(Page page, int YXdo&'Q<qX
ps/|^8aGZ
totalRecords){ ,t'"3<^Jg
return createPage(page.getEveryPage(), 6_tl_O7
F2)KAIl
page.getCurrentPage(), totalRecords); 9u3P>a~b
} %\!0*(8
2%H_%Zu9
/**
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* the basic page utils not including exception 4"^W/Zo
X@)'E9g5:
handler ~1S,[5u|s
* @param everyPage F
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* @param currentPage (4rHy*6
* @param totalRecords rj1%IzaXU^
* @return page |0_5iFAB|
*/ E?Qg'|+_
publicstatic Page createPage(int everyPage, int lf R}cx
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currentPage, int totalRecords){ 6&2{V?
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everyPage = getEveryPage(everyPage); _C'VC#Sy
currentPage = getCurrentPage(currentPage); ]/[@.
int beginIndex = getBeginIndex(everyPage, /}CAd
*ck'vV'@
currentPage); rK'O 85)eU
int totalPage = getTotalPage(everyPage, ("<4Ry.u
Fa #5a'}I
totalRecords); $lUz!mjG
boolean hasNextPage = hasNextPage(currentPage, 8CvNcO;H0
m/,8\+
totalPage); GQE7P()
boolean hasPrePage = hasPrePage(currentPage); q)YHhH\
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returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, {L M Q
currentPage, /}5)[9GC
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beginIndex); z`]:\j'O3"
} ~ntDzF
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privatestaticint getEveryPage(int everyPage){ =~21.p
return everyPage == 0 ? 10 : everyPage; eX0[C0#
} <LX-},?P
y'^b{q@
privatestaticint getCurrentPage(int currentPage){ w.=rea~
return currentPage == 0 ? 1 : currentPage; 4NIb_E0
} aq(i^d
Kzwe36O;?
privatestaticint getBeginIndex(int everyPage, int H8Z|gq1r
&nY#GHB
currentPage){ O}6*9Xy
return(currentPage - 1) * everyPage; ydE}.0zN
} F C=N}5u
9*r l7
privatestaticint getTotalPage(int everyPage, int 8N`Rf;BM
> aCY
totalRecords){ 5R1?jlm
int totalPage = 0; (Q.I DDlr
}|znQ3A2\l
if(totalRecords % everyPage == 0) l
o-
42)
totalPage = totalRecords / everyPage; iU#"G" &
else #aKUD
totalPage = totalRecords / everyPage + 1 ; JPg^h
\e%%ik,<
return totalPage; _) UnHp_^
} un)PW&~E
UGoB7TEfn
privatestaticboolean hasPrePage(int currentPage){ h6;zAM}
return currentPage == 1 ? false : true; W"tGCnd
} ^<j
=.E
5`::#[
privatestaticboolean hasNextPage(int currentPage, }=u#,nDl>$
# `@jVX0
int totalPage){ +.xK`_[M
return currentPage == totalPage || totalPage == Lu4>C 2{
$3eoZ1q'U-
0 ? false : true; VpED9l]y
} [-R[rF
`SS[[FT$>
>U]KPL[%
} TA~ZN^xI
nu[["f~
g5*?2D}dqX
/?}2OCq
/9?yw!
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。 0XA0b1V X
yFTN/MFt
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 ]Z*B17//
<s'0<e!./t
做法如下: zV"'-iP
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <."
@H<-`*
&@D\4b,?nm
的信息,和一个结果集List: z<9Llew^e
java代码: "#w%sG^_
+IlQZwm~
-<(RYMk*)
/*Created on 2005-6-13*/ df&.!7_R`
package com.adt.bo; gy"<[N
.?c
8,&Y\b`..
import java.util.List; C8}
;,
|vxmgX)
import org.flyware.util.page.Page; bfK4ps}m*
.k|\xR
/** FRayB VHL
* @author Joa cV4Y=
&
*/ ^szi[Cj
publicclass Result { P5lk3Zg'
Iq
0ew
private Page page; 1*trtb4F
g3(LDqB'.
private List content; 6Q]JY,+
:kd]n$]
/** v8C4BuwA
* The default constructor {~XnmBs
*/ "h8fTB\7S\
public Result(){ x_wWe>0
super(); `dRqheX
} F;BCSoO4
,}wFQ9*|W
/** A-YW!BT4
* The constructor using fields QI78/gT,d
* ]3 QW\k~
* @param page \=o0MR
* @param content {*K$gH$
*/ T*'WS!z
public Result(Page page, List content){ Sar1NkD#
this.page = page; .=9d3uWJ/
this.content = content; 4`")aM
} S,vdd7Y
rCb#E}
/** (D{J|
* @return Returns the content. z:u)@>6D1
*/ K@a#^lmd
publicList getContent(){ R 'fEw3^
return content; Ns5P,[pBOZ
} j}6h}E&dEr
V~do6[(
/** tjx|;m7
* @return Returns the page. ZEvK
*/ )g KC}_h=
public Page getPage(){ )RQQhB
return page; pX1Us+%
} )c532
y
J5Ti@(G5V
/** FOjX,@x&
* @param content n+nZ;GJ5d
* The content to set. iU(B#ohW"
*/ %.HLO.A
public void setContent(List content){ 5Sb-Bn
this.content = content; ]ZNFrpq
} Q8$;##hzt
{uJ"%
/** SIc~cZ!Yu
* @param page _CBMU'V
* The page to set. "/ Gw`^t
*/ "F4 3q8 P
publicvoid setPage(Page page){ _'*(-K5&
this.page = page; : t/0
} %P:|B:\<
} [ 6Sk>j
`7[!bCl
$9:
@M.
O2"V'(
ln8es{q
2. 编写业务逻辑接口,并实现它(UserManager, %,zHS?)l
r|i)
UserManagerImpl) ^dE[ ;
java代码: n~tb z"&
G\^<MR|
O- LwX
>
/*Created on 2005-7-15*/ pgZQ>%
package com.adt.service; QS1lg
($W%&(:/
import net.sf.hibernate.HibernateException; }>V=J aG
w\{#nrhYU
import org.flyware.util.page.Page; hTmJ
~m'J
6\`8b&'n
import com.adt.bo.Result; 15yiDI
o
f.uy;v
/** O\)Kg2
* @author Joa H({m1v ~R
*/ <FI*A+I4\
publicinterface UserManager { IreY8.FND
gyhy0
public Result listUser(Page page)throws dczSW]%
]Tg@wMgI
HibernateException; 2 )3oX
,t:P
} Ge7B%p8
W1Ye+vg/s
,+I]\ZeO
%s^1 de
G;EJ\J6@Yw
java代码: 5)5yH bS
8si{|*;hL
VT=gb/W6)a
/*Created on 2005-7-15*/ PsD)]V9%:
package com.adt.service.impl; 0rm(i*Q
o[i*i<jv-
import java.util.List; dDD5OnWmJ
O f-xGoYZ
import net.sf.hibernate.HibernateException; S.q0L
bOp%
import org.flyware.util.page.Page; D5f[:
import org.flyware.util.page.PageUtil; (hg6<`
;%^{Zybh
import com.adt.bo.Result; !hHX8TD^J
import com.adt.dao.UserDAO; 0,Ib74N'w
import com.adt.exception.ObjectNotFoundException; .yFO]
r1aL
import com.adt.service.UserManager; KWAd~8,mk
oe0YxSauL
/** Q]3]Z/i
* @author Joa =1'WZp}D5
*/ bf{_U%`
publicclass UserManagerImpl implements UserManager { LsaX
HI/?b
yPs6_Qo!p
private UserDAO userDAO; >Gk<a
po,Ue>n/
/** %[M0TE=J
* @param userDAO The userDAO to set.
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*/ H)EL0
Kv/
publicvoid setUserDAO(UserDAO userDAO){ GIn%yB'
this.userDAO = userDAO; {2q0Ko<
} 8eYEi
=tP^vgfQ
/* (non-Javadoc) +
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* @see com.adt.service.UserManager#listUser 7J
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B([-GpZt[
(org.flyware.util.page.Page) 'J5F+,\Ka
*/ AO|1m$xf
public Result listUser(Page page)throws ^u1Nbo
8#- Nx]VM
HibernateException, ObjectNotFoundException { uXLZ!LJo
int totalRecords = userDAO.getUserCount(); %e3E}m>
if(totalRecords == 0) V0W4M%
throw new ObjectNotFoundException V\opC6*L_e
DS>&|zF5l
("userNotExist"); vqO#Z
page = PageUtil.createPage(page, totalRecords); dNF_T?E\
List users = userDAO.getUserByPage(page); `'k2gq&
returnnew Result(page, users);
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} \8s:I+[HH
pV;0Hcy
} w-xigm>{Z
>goHQ30:
5??}9
\i@R5v=zL
qu dY9_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 [@8 po-()L
kWy@wPqms
询,接下来编写UserDAO的代码: b-#lKWso
3. UserDAO 和 UserDAOImpl: D6+3f#k6
java代码: "5O>egt
CR%h$+dzy
}#%Ye CA?
/*Created on 2005-7-15*/ -!O8V
package com.adt.dao; z,7;+6*=L
@:#J^CsM+'
import java.util.List; + G[zE
|yzv o"3
import org.flyware.util.page.Page; Il(o[Q>jJ3
96QY0
import net.sf.hibernate.HibernateException; CSq|R-@<U
?Tu=-ppw
/** N- knhA
* @author Joa ~{5va
*/ nvXjW@)`
publicinterface UserDAO extends BaseDAO {
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{;& U5<NO
publicList getUserByName(String name)throws Y~A I2H S
Az8ZA ~Op=
HibernateException; QV:> x#=V
SE@TY32T
publicint getUserCount()throws HibernateException; e*PUs
$C fp1#
publicList getUserByPage(Page page)throws JMo r[*
(w5cp!qW9J
HibernateException; %N&W_.F6
?wCX:?g
} F ]Zg
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Bp5ra9*5+~
9+s&|XS*
YM'4=BlJHv
java代码: CI$z+zN
/2c(6h
s@7h oU-+
/*Created on 2005-7-15*/ X;GU#8W
package com.adt.dao.impl; 4;CI<&S
SJMbYjn0J
import java.util.List; 3W_7xLA
cSV&p|
import org.flyware.util.page.Page; uL1lB@G@
]4c+{
import net.sf.hibernate.HibernateException; Pmd[2/][
import net.sf.hibernate.Query; .r6x9t
kh2TDxa&
import com.adt.dao.UserDAO; X#JUorGp
|m"Gr)Gm
/** \R]2YY`EP
* @author Joa L3xN#W;m7
*/ *.k*JsU~B
public class UserDAOImpl extends BaseDAOHibernateImpl % X %zK1
g)r{LxT# +
implements UserDAO { =RRv&
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/* (non-Javadoc) U.P1KRY|=
* @see com.adt.dao.UserDAO#getUserByName QSa#}vCp*
R2-F@_
(java.lang.String) 3e1-w$z&S
*/ Uuu2wz3O0
publicList getUserByName(String name)throws :Hm'o}
Xo~q}(ze^
HibernateException { 0+@:f^3]!
String querySentence = "FROM user in class ZCc23UwI
6Z J-oT!.
com.adt.po.User WHERE user.name=:name"; 7kE+9HmfMk
Query query = getSession().createQuery
3x+=7Mg9
2sk7E'2(
(querySentence); ``:[Jr&
query.setParameter("name", name); NQ 6oyg@&
return query.list(); 1v`|mU}i,
} E7? n'!=
j<0;JAL
/* (non-Javadoc) {2P18&=
* @see com.adt.dao.UserDAO#getUserCount()
nYZ6'Iwi'
*/ Y)5O %@Rl
publicint getUserCount()throws HibernateException { la-:"gKC
int count = 0; *!&?Xy%\"j
String querySentence = "SELECT count(*) FROM ,pGA|ob
4}/gV)
user in class com.adt.po.User"; f)z(9JJL
Query query = getSession().createQuery ly[dV.<P
GuU-<*u(d
(querySentence); eUB!sR%
count = ((Integer)query.iterate().next "49dsKIOH
{%9@{Q'T.s
()).intValue(); vCJa%}
return count; ny1O- `!1
} md'wre3
a@W9\b@I
/* (non-Javadoc) \ Voly
* @see com.adt.dao.UserDAO#getUserByPage 0q-lyVZ^X
7>O`UT<t4@
(org.flyware.util.page.Page) 8uLS7\,$z
*/ o)@nnqa
publicList getUserByPage(Page page)throws kG!hqj
xlwf @XW
HibernateException { T:{r*zLSN
String querySentence = "FROM user in class [(#)9/3,
# M/n\em"X
com.adt.po.User"; Wd)\r.pJ
Query query = getSession().createQuery $Uy+]9
^?""'1iuQx
(querySentence); M3@qhEf?vk
query.setFirstResult(page.getBeginIndex()) s<!G2~T
.setMaxResults(page.getEveryPage()); w[gt9]}N
return query.list(); ;iKtv+"
} fv8x7l7
@XzfuuE]
} k@|px#kq
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bRm;d_9zC
r.#r!.6 q
r1%{\<
至此,一个完整的分页程序完成。前台的只需要调用 %?gG-R
a"U3h[;$y
userManager.listUser(page)即可得到一个Page对象和结果集对象 -sJD:G,%
q&v~9~^}d
的综合体,而传入的参数page对象则可以由前台传入,如果用 !10/M
rmkBp_i{|
webwork,甚至可以直接在配置文件中指定。 K\U`gTGc
IMqe(
下面给出一个webwork调用示例: [iq^'E
java代码: E#rQJ
vMou`[\WlJ
,s3|
/*Created on 2005-6-17*/ aXVldt'
package com.adt.action.user; WcKDerc
qX-5/;n
import java.util.List; Ah7"qv'L\
)?#K0o[<
import org.apache.commons.logging.Log; @hg[v`~
import org.apache.commons.logging.LogFactory; N^[
F+y
import org.flyware.util.page.Page; >VIFQ\
2ak]&ll+h
import com.adt.bo.Result; k
$^/$N
import com.adt.service.UserService; TU~y;:OJ
import com.opensymphony.xwork.Action; mp$IhJ6#
`Pj7:[."[
/** er3~gm
* @author Joa ^lV}![do!
*/ V>)/z|[
publicclass ListUser implementsAction{ MSM8wYcD
B;=Z^$%T
privatestaticfinal Log logger = LogFactory.getLog }a5TY("d9H
y<- ]'Yts
(ListUser.class); w(ZZTVW-
R)Mkt8v
private UserService userService;
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RNB&!NC
private Page page; }9\6!GY0
61kSCu
privateList users; BI)C\D3[
C;JW\J~W
/* #bt f|\D
* (non-Javadoc) 9;7"S.7AV
* @B>D>B
* @see com.opensymphony.xwork.Action#execute() 7_s+7x =
*/
B(s^(__]
publicString execute()throwsException{ 8TB|Y
Result result = userService.listUser(page); m"Mj3Z:
page = result.getPage(); r4iNX+h?V
users = result.getContent(); V||b%Cb1g
return SUCCESS; zx\-He
} de W1>yh^_
]FVJQS2h
/** )YEAk@h@
* @return Returns the page. W>w(|3\
*/ EL3X8H
public Page getPage(){ `(?c4oq,c>
return page; +fboTsp% H
} M}11 tUl
vJ&D>Vh4e
/** `O2P&!9&
* @return Returns the users. yD& Y`f#
*/ y'^U4# (
publicList getUsers(){ DQW)^j
h
return users; L{jx'[C
} wMCg`rk
BSHS)_xs
/** 3)W_^6>bM
* @param page HJg&fkHn1
* The page to set. |^5"-3Q
*/ F5x*#/af
publicvoid setPage(Page page){ (kY0<
this.page = page; S"G(_%
} uQ_C<ii"W
s&VsK#
/** 7/hn%obC
* @param users YL|)`m0-^5
* The users to set. 084Us
s
*/ T<Xw[PEnP
publicvoid setUsers(List users){ u4
es8"
this.users = users; 1\@PrO35J
} qZ[HILh!
fTR6]i;
/** 6:%lxG
* @param userService )ddJ\:
* The userService to set. s/hWhaS<
*/ l+2NA4s
publicvoid setUserService(UserService userService){ P]^OSPRg
this.userService = userService; !Q~>)$Cf^
} b6k_u9m^E
} @R`6jS_gK
D
ON.)F
E@k'uyIu
XTX/vbge3m
y{3+Un
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, R3og]=uFzm
AC
<2.i_
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 U{ 0~&
~xY"P)(x;
么只需要: zOSUYn
java代码: 1QA/ !2E
7)<Ib
j<M
*j&\5|^V
<?xml version="1.0"?> EmO[-W|2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork X(x,6cC
|(Wwh$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *V:U\G
XZ.D<T"
1.0.dtd"> iP9]b&
XYP
RMa?
<xwork> 6p)&}m9!
Peph..8 Z
<package name="user" extends="webwork- y>t:flD*
PCaFG;}
interceptors"> L`<#vi
WG A&Lr
<!-- The default interceptor stack name 46)[F0,$r
C TG^lms
--> V2?{ebx`
<default-interceptor-ref yc]_ ?S>9
"4WnDd5"
name="myDefaultWebStack"/> +pT;;
9
Jxe 5y3*
(
<action name="listUser" #y#TEw,
X1P1
$RdkR
class="com.adt.action.user.ListUser"> 4.,|vtp
<param ^kcuRJ0*$
8i;drvf
name="page.everyPage">10</param> {ST8'hY
<result ZMMx)}hS
ec#`9w$
name="success">/user/user_list.jsp</result> gh[q*%#
</action> 3O*iv{-&
*>qc6d@'
</package> %KO8i)n
5s^vC2$)
</xwork> Wx3DWY;
r]xN&Ne5Q
N9d^;6;i
[-l>fP0
8g{Mv#b%
Ygg+=@].@
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 mB0`>?#i
<astIu Au
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 3)>re&
X$ul=iBs
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 @ ^F{
kb~
s,@p
Oz\J+
,)\G<q
yO6
]5
]wyDj
我写的一个用于分页的类,用了泛型了,hoho
AX+]Z$
_Fj\0S"
java代码: n7ZJ< ~wl
%2D'NZS
H&*&n}vh5y
package com.intokr.util; I&15[:b=-
}vB{6E+h/w
import java.util.List; lgVT~v{U`n
In%FOPO
/** .Gr"|uII
* 用于分页的类<br> })@xWU6!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> J:uFQWxZ
* {c?{M.R
* @version 0.01 hA/Es?U]
* @author cheng +7WpJ;C4
*/ p[WlcbBwT
public class Paginator<E> { ~yXDN4s
privateint count = 0; // 总记录数 R=R]0
privateint p = 1; // 页编号 U"@p3$2QW
privateint num = 20; // 每页的记录数 En-=z`j
G
privateList<E> results = null; // 结果 Y=sv
F\;l)
/** T<nK/lp1t
* 结果总数 M^l%*QF[,q
*/ ueW/i
publicint getCount(){ e]!`94f
return count; s]=XAm"4
} ixM#|Yq
gP8}d*W%b
publicvoid setCount(int count){ L28wT)D-
this.count = count; ;
1?L
} yP-$@Ry
.aWwJZ=[
/** 9(=+OQ6
* 本结果所在的页码,从1开始 z/5TYv)S
* *pS3xit~
* @return Returns the pageNo. %y>*9$<pXe
*/ mrsN@(X0
publicint getP(){ 3\ )bg
R:
return p; %|/\Qu
} vqUYr
<Cs9$J
/** s;Z i
* if(p<=0) p=1 56C'<#
* _8`S&[E?
* @param p P%w!4v~"
*/ |,.1=|&u
publicvoid setP(int p){ ~|{e"!(}
if(p <= 0) 6eB~S)Ko
p = 1; kJ.7C
this.p = p; HCktgL:E=
} c0jTQMe4yl
J~@W":v
/**
_,Q -)\
* 每页记录数量 i[33u p
*/ Mp5Z=2l5
publicint getNum(){ .Q</0*sp
return num; IA=\c
} ]U4C2}u
Ttb ?x<)+8
/** -DZ5nx
* if(num<1) num=1 j~Ci*'*L
*/ 8&x&Ou$("V
publicvoid setNum(int num){ /^~)iTwH
if(num < 1)
y(C',Xn
num = 1; 44^jE{,9
this.num = num; ] : ](xW%
} qw|B-lT{:
n%vmo
f
/** "0>AefFd#
* 获得总页数 6lr<{k7Nw
*/ 6: R1jF*eG
publicint getPageNum(){ ^#h ;bX#
return(count - 1) / num + 1; Yv{$XI7
} c;
1f$$>b
'vZWkeo
/** |F=.NY
* 获得本页的开始编号,为 (p-1)*num+1
(w<llb`]
*/ sA"B/C|(g
publicint getStart(){ \<}e?Yx%
return(p - 1) * num + 1; gZz5P>^
} 2R3)/bz-SV
}&l%>P
/** dZd]p8
* @return Returns the results. /5>A 2y
*/ \3rgwbF
publicList<E> getResults(){ T%TO?[cN
return results; 7;#o?6!7
} PMj!T \B|
$U^ Ms!'L
public void setResults(List<E> results){ V1,4M _Z
this.results = results; xiC.M6/
} u3 4.
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public String toString(){ )4GCL(&
StringBuilder buff = new StringBuilder QcdAg%"yy
.g_Kab3?L
(); >bw q
buff.append("{"); '_n$xfH
buff.append("count:").append(count); 0e'@Xo2e
buff.append(",p:").append(p); [GW;RjPE
buff.append(",nump:").append(num); A22'qgKm@
buff.append(",results:").append dP/1E6*m
~NK|q5(I
(results); 8(:O5#
buff.append("}"); z_$F)*PL
return buff.toString(); .k5&C/jv
} S]c&