Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 x5vzPh`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 _3&/(B%H
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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 <9N4"d!A
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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 ,.7vBt6 p
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分页支持类: jkCHi@
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java代码: BHclUwj
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package com.javaeye.common.util; ULu O0\W
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import java.util.List; c}cG<F
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publicclass PaginationSupport { Cqa3n[Mhw1
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publicfinalstaticint PAGESIZE = 30; B$`d&7I;D
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privateint pageSize = PAGESIZE; '\'7yN'
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privateList items; ?\d5;%YSr
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privateint totalCount; J~'~[,K
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privateint[] indexes = newint[0]; 1:5P%$?b
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privateint startIndex = 0; E6Q91Wz9f
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public PaginationSupport(List items, int 0STk)>3$-
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totalCount){ x3_,nl
setPageSize(PAGESIZE); 8_Jj+
setTotalCount(totalCount); 9Q=>MOB-
setItems(items); ^T+<!k
setStartIndex(0); 1sMV`qv>
} !,R
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public PaginationSupport(List items, int !8Y3V/)NU
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totalCount, int startIndex){ i
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setPageSize(PAGESIZE); k3/4Bt G/
setTotalCount(totalCount); wvX"D0eVn
setItems(items); "V:XhBG?
setStartIndex(startIndex); Iw*C*%}[Z
} e00RT1L
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public PaginationSupport(List items, int JkJhfFV
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totalCount, int pageSize, int startIndex){ T77)Np
setPageSize(pageSize); P2 |}*h5(
setTotalCount(totalCount); g\qX7nIH?
setItems(items); jigbeHRy
setStartIndex(startIndex); FfjC
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} &'NQ)Dn
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publicList getItems(){ )v};C<
return items; Jfe~ ,cI
} L#[HnsLp_
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publicvoid setItems(List items){ Dn: Yi8=
this.items = items; KZi+j#7O
} H]U"+52h
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publicint getPageSize(){ U:J /\-
return pageSize; ZIDFF
} rx{#+iw
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publicvoid setPageSize(int pageSize){ F61+n!%8
this.pageSize = pageSize; >[
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} ,,XS;X?
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publicint getTotalCount(){ fO0-N>W'P
return totalCount; +Z )`inw
} CCC4(v
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publicvoid setTotalCount(int totalCount){ =":@Foa
if(totalCount > 0){ ZjE~W>pkQ
this.totalCount = totalCount; qmQFHC_
int count = totalCount / Lax9
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pageSize; ozT._C
if(totalCount % pageSize > 0) \]Kq(k[p
count++; }`#j;H$i
indexes = newint[count]; ='KPT1dW*
for(int i = 0; i < count; i++){ bn5"dxV
indexes = pageSize * 9tW3!O^_
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i; O2/%mFS.
} (2n3exx
}else{ >3v0yh_3
this.totalCount = 0; w($XEv;
} KwY`<t1lA;
} $cyLI+uz|
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publicint[] getIndexes(){ &mCs%l
return indexes; (
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} *4zoAs lU1
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publicvoid setIndexes(int[] indexes){ hLu&lY
this.indexes = indexes; o,iS&U"TC
} >6n@\n
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publicint getStartIndex(){ $[WN[J
return startIndex; x*3@,GmZl
} y[TaM9<
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publicvoid setStartIndex(int startIndex){ n\~"Wim<b
if(totalCount <= 0) }S
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this.startIndex = 0; ag|9$
elseif(startIndex >= totalCount) BF@m)w.v
this.startIndex = indexes t201ud2$
hj%}GP{{
[indexes.length - 1]; %w;1*~bH
elseif(startIndex < 0) m~b#:4D3
this.startIndex = 0; =f/avGX
else{ wCqE4i
this.startIndex = indexes K+(m'3`
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[startIndex / pageSize]; <h)deB+}
} **"zDY*?W
} #sozXza\G
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publicint getNextIndex(){ cuJ/ Vc
int nextIndex = getStartIndex() + ,:\zXESy4
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pageSize; bvt-leA=
if(nextIndex >= totalCount) r>n8`W
return getStartIndex(); 18l~4"|fk
else h5h-}qBA
return nextIndex; 1"87EP
} _Eet2;9
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publicint getPreviousIndex(){ B'<O)"1w
int previousIndex = getStartIndex() - c~Q`{2%+
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pageSize; rElG7[+)p
if(previousIndex < 0) F5b]/;|
return0; p1[WGeV
else 0~LnnDN
return previousIndex; &q kl*#]
} wpPxEp/
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} >rQ)|W=i
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抽象业务类 ]}*G[[
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java代码: +LvZ87O^~
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/** >QbI)if`1
* Created on 2005-7-12 |wl")|b%
*/ |2+c DR
package com.javaeye.common.business; i1kh@s~8UC
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import java.io.Serializable; #==[RNM%ap
import java.util.List; `qQQQ.K7)z
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import org.hibernate.Criteria; Fp* &os
import org.hibernate.HibernateException; ixUiXP
import org.hibernate.Session; QQ2OZy>W
import org.hibernate.criterion.DetachedCriteria; #EwRb<'Em
import org.hibernate.criterion.Projections; @idp8J [td
import O>{t}6o
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org.springframework.orm.hibernate3.HibernateCallback; 60SenHKles
import oD|+X/FK
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org.springframework.orm.hibernate3.support.HibernateDaoS YjMbd?v
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upport; $ET/0v"V
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import com.javaeye.common.util.PaginationSupport; p5D3J[?N
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public abstract class AbstractManager extends Amq8q
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HibernateDaoSupport { M 2U@gC|{
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privateboolean cacheQueries = false; iKCTYXN1(
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privateString queryCacheRegion; S
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publicvoid setCacheQueries(boolean E,nYtn|B
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cacheQueries){ {yl/T:Bh&
this.cacheQueries = cacheQueries; `~s,W.Eu4
} =Am*$wGI
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publicvoid setQueryCacheRegion(String 7{6cLYl
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queryCacheRegion){ bl QzVp-
this.queryCacheRegion = jmwQc&
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queryCacheRegion; 67hPQ/S1
} ztt%l #
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publicvoid save(finalObject entity){ uR[PKLh
getHibernateTemplate().save(entity); I'wk/
} d}A2I
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publicvoid persist(finalObject entity){ mU0r"\**c3
getHibernateTemplate().save(entity); Ny&Fjzl
} %.Q2r ?j
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publicvoid update(finalObject entity){ + xu/RY_
getHibernateTemplate().update(entity); w[n>4?"{
} DqC}f#
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publicvoid delete(finalObject entity){ E* DVQ3~
getHibernateTemplate().delete(entity); %W|Zj QI^
} @XSu?+s)
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publicObject load(finalClass entity, a(QZZq};S
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finalSerializable id){ $9u
return getHibernateTemplate().load xWI 0s;k
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(entity, id); P(gID
} T"0)%k8lJ
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publicObject get(finalClass entity, M5bj |tQ4
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finalSerializable id){ , $F0D
return getHibernateTemplate().get jH#^O;A
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(entity, id); ;ZW}47:BS6
} >[3,qP]E
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publicList findAll(finalClass entity){ R@{/$p:
return getHibernateTemplate().find("from .}u(&
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" + entity.getName()); -W"0,.Dvg
} "a_D]D(d5
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publicList findByNamedQuery(finalString F/,<dNJ
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namedQuery){ :{= 'TMJ7
return getHibernateTemplate Q)i`.mHfFI
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().findByNamedQuery(namedQuery); R;m0eG`
} R~?; KJ
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publicList findByNamedQuery(finalString query, oL/^[TXjH
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finalObject parameter){ X;a{JjN
return getHibernateTemplate r H_:7#.E
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().findByNamedQuery(query, parameter); 8t
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} GP
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publicList findByNamedQuery(finalString query, Oh85*3
?F), 4Q
finalObject[] parameters){ uF|ix.R6
return getHibernateTemplate >WS&w;G
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().findByNamedQuery(query, parameters); FH5 bC6
} 2A;[Ek6{q
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publicList find(finalString query){ m6ws#%|[
return getHibernateTemplate().find .F$AmVTN
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(query); 8qLgB
} x;]{ 8#-z
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publicList find(finalString query, finalObject r4>I?lD
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parameter){ p?NjxQLA
return getHibernateTemplate().find L/+J|_J)
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(query, parameter); %H~gN9Vn#@
} #\;w::
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public PaginationSupport findPageByCriteria NB#*`|qt
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(final DetachedCriteria detachedCriteria){ VYQbyD{V w
return findPageByCriteria 1EPOYvf%U
%{_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?B!ZqJ#
} ~0{Kga
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public PaginationSupport findPageByCriteria T@WMT,J6j
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(final DetachedCriteria detachedCriteria, finalint T/6=A$4
#
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startIndex){ 6(^9D_"@
return findPageByCriteria ,(=]6V
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(detachedCriteria, PaginationSupport.PAGESIZE, vj$6
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startIndex); 0qUap*fvC
} 1}M.}G2u/
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public PaginationSupport findPageByCriteria m
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(final DetachedCriteria detachedCriteria, finalint OYy !4Fp
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pageSize, ng*E9Puu[
finalint startIndex){ F}DD;K
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ e>Y2q|S85
publicObject doInHibernate ?0%TE\I8
0l@+xS;
(Session session)throws HibernateException { lM%fgyX
Criteria criteria = }]?G"f
t K
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = o+Z9h1z%,
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((Integer) criteria.setProjection(Projections.rowCount ,LO-!\L
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()).uniqueResult()).intValue(); mcG$V0D <{
criteria.setProjection ]*U')
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(null); e.^9&Fk"N
List items = *v3
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criteria.setFirstResult(startIndex).setMaxResults 9Dw&b
iCKwd 9?)
(pageSize).list(); _q4m7C<
PaginationSupport ps = ='>UKy[=
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new PaginationSupport(items, totalCount, pageSize, ,4,c-
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startIndex); +eXfT*=u5
return ps; 0Wm-`ZA
} <J`xCm K
}, true); elB 8
} d~8~RT2m
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public List findAllByCriteria(final A$6b=2hc>
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DetachedCriteria detachedCriteria){ H12@12v
return(List) getHibernateTemplate 8E[`H
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().execute(new HibernateCallback(){ x&vD,|V!
publicObject doInHibernate W2N 7
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(Session session)throws HibernateException { Th^#H
Criteria criteria = i8.[d5
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detachedCriteria.getExecutableCriteria(session); -P&e4sV{
return criteria.list(); L{pg?#\yC
} H-w|JH>g
}, true); < z)G& h@
} Uk6!Sb
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public int getCountByCriteria(final j}l8k@f
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DetachedCriteria detachedCriteria){ ;~1JbP
Integer count = (Integer) w'XgW0j{
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getHibernateTemplate().execute(new HibernateCallback(){ n#cN[C9
publicObject doInHibernate V}-o):dI|
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(Session session)throws HibernateException { _6
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Criteria criteria = T_T{c+,Zd$
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detachedCriteria.getExecutableCriteria(session); Am4(WXVQ
return 2,0F8=L
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criteria.setProjection(Projections.rowCount mA@+4&
pa-4|)qY
()).uniqueResult(); Jx w<*
} m)}MkC-
}, true); cO&9(.d
return count.intValue(); [^~9wFNtd
} Q;nr=f7Ys
} K/cK6Yr
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用户在web层构造查询条件detachedCriteria,和可选的 _9r{W65s
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {m:R v&T
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PaginationSupport的实例ps。 gQ#T7
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ps.getItems()得到已分页好的结果集 cU|jT8Q4H
ps.getIndexes()得到分页索引的数组 Hc|U@G
ps.getTotalCount()得到总结果数 *pp1Wa7O
ps.getStartIndex()当前分页索引 ^^uD33@_
ps.getNextIndex()下一页索引 +9CUnRv
ps.getPreviousIndex()上一页索引 k1zt|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ifZNl,
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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 ,$$$_+m\
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一下代码重构了。 !H\GHA'DO]
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我把原本我的做法也提供出来供大家讨论吧: Qpf]3
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首先,为了实现分页查询,我封装了一个Page类: 0u2uYiE-l
java代码: yVzg<%CR^
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/*Created on 2005-4-14*/ uf]$@6)
package org.flyware.util.page; vyGLn
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/** IQ~7vk()
* @author Joa mkzk$_
* =A6O}0z
*/ %= y3
publicclass Page { Q}]kw}b
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/** imply if the page has previous page */ 1Z8oN3
privateboolean hasPrePage; ]
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/** imply if the page has next page */ ;@~*z4U
privateboolean hasNextPage; :Xh`.*{EX
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/** the number of every page */ 5V8C+k)
privateint everyPage; :9#{p^:o
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/** the total page number */ /+O8A}
privateint totalPage; 15DK\_;
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/** the number of current page */ -GVG1#5
privateint currentPage; HW Os@!cL
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/** the begin index of the records by the current }/3pC a
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query */ %v:h]TA
privateint beginIndex; K/m)f#
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/** The default constructor */ chzR4"WZFt
public Page(){ D-:<]D:
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} pF+wHMhUe
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/** construct the page by everyPage 9$@ g;?}Ps
* @param everyPage ~c$ts&Cl
* */ C?|3\@7
public Page(int everyPage){ ~9YA!48
this.everyPage = everyPage; [c[MQA0
} Er1u1@
U*"cf>dB(
/** The whole constructor */ rGGepd
public Page(boolean hasPrePage, boolean hasNextPage, HKN"$(Q
qpqz. {\
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int everyPage, int totalPage, 3N0X?* (x|
int currentPage, int beginIndex){ E?4@C"Na
this.hasPrePage = hasPrePage; Mr,y|
this.hasNextPage = hasNextPage; <;E[)tv
this.everyPage = everyPage; m{dyVE
this.totalPage = totalPage; (jMAa%
this.currentPage = currentPage; Cf=q_\0|W
this.beginIndex = beginIndex; TM}'XZ&
} ?iEXFYJG
dN/ "1%9)
/** l~!fQ$~
* @return C!k9 JAa$Z
* Returns the beginIndex. rnv7L^9^A
*/ b\j&!_
publicint getBeginIndex(){ L(2P|{C
return beginIndex; VN-#R=D
} O| 6\g>ew
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/** BI.k On=
* @param beginIndex D6)Cjc>a
* The beginIndex to set. V0
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*/ + >gbZ-S
publicvoid setBeginIndex(int beginIndex){ nf.:5I.
this.beginIndex = beginIndex; @))}\:
} qTh='~m4[
%i
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/** ^ lc}FN
* @return :`u&TXsu
* Returns the currentPage. K[>@'P}y
*/ UtBlP+bE?y
publicint getCurrentPage(){ i,Wm{+H-O
return currentPage; }A)36
} 0Q-
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/** f,HzrHax
* @param currentPage io r [v
* The currentPage to set. ?}3PJVy?
*/ j_'rhEdLP
publicvoid setCurrentPage(int currentPage){ @f5@0A\0
this.currentPage = currentPage; :&0yf;>v
} :{i$2\DH6
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/** ^c0$pqZ}r
* @return y.*=Ww+
* Returns the everyPage. kuj12
*/ jFNs=D&(
publicint getEveryPage(){ '0_j{ig
return everyPage; -Mi}yi
} *iRm`)zC(
j
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/** <A -(&+
* @param everyPage ;?L!1wklA
* The everyPage to set.
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*/ $]H=
publicvoid setEveryPage(int everyPage){ hLytKPgt
this.everyPage = everyPage; :ONuWNY
N
} lO2T/1iMTW
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/** <{NYD.
* @return h-b5
* Returns the hasNextPage. h/X5w4
*/ )}Rfa}MD
publicboolean getHasNextPage(){ ,P@/=I5
return hasNextPage; L;--d`[
} v :+8U[x
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/** .qIy7_^
* @param hasNextPage Od!F: <
* The hasNextPage to set. Y1fy2\<'
*/ @k+%y'Y?
publicvoid setHasNextPage(boolean hasNextPage){ q
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this.hasNextPage = hasNextPage; ;naq-%'Sg
} NlF0\+h
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/** {7=WU4$
* @return 'ybth
* Returns the hasPrePage. ."IJmv
*/ xMNNXPz(
publicboolean getHasPrePage(){ 9QH9gdiw
return hasPrePage; 0eqi1;$b]
} J+71FP`ZH
&SjHrOG?
/** .|-l+
* @param hasPrePage hg?j)jl|
* The hasPrePage to set. #*Yi4Cn<
*/ P.LuF(?$
publicvoid setHasPrePage(boolean hasPrePage){ 7b&JX'`Mb
this.hasPrePage = hasPrePage; (# 6<k
} TvunjTpaj
$hjP}- oUX
/** K\IYx|Hm a
* @return Returns the totalPage. &Y54QE".
* 0%xR<<gir
*/ GJ1;\:cQq
publicint getTotalPage(){ d ~{jEg
return totalPage; KE/-VjZu
} ?$|uT
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/** 9Z,*h-o
* @param totalPage {W5ydHXy
* The totalPage to set. bJQ5- *F
*/ AT B\^;n.
publicvoid setTotalPage(int totalPage){ cOSxg=~>u
this.totalPage = totalPage; eyeNrk*2o
} [G{rHSK5tQ
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} r}/yi
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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 nG"tO'J6
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个PageUtil,负责对Page对象进行构造: k}-yOP{
java代码: 1~}m.ER
yZYKwKG
PsU9R#HL1
/*Created on 2005-4-14*/ R K"&l!o
package org.flyware.util.page; UL86-R!
L5"8G,I
import org.apache.commons.logging.Log; '[Mlmgc5
import org.apache.commons.logging.LogFactory; 3iE-6udCS
^FP}
qW~;9
/** ZCy`2Fir
* @author Joa 3@^MvoC
* tHrK~|
*/ }JRP,YNh
publicclass PageUtil { ecr886
Ua):y) A
privatestaticfinal Log logger = LogFactory.getLog L|&'jH)
$.H:8^W
(PageUtil.class); ;~W8v.EW
Zimh_
/** SArfczoB
* Use the origin page to create a new page P!kw;x
* @param page lj.nCV_
* @param totalRecords kTnOmAw
* @return >qR7'Q wP
*/ vB[~pQ;Z
publicstatic Page createPage(Page page, int <,\ `Psa)N
W7H&R,
totalRecords){ _i5mC,OffN
return createPage(page.getEveryPage(), U?gl"6x
tbtI1"$
page.getCurrentPage(), totalRecords); C>.e+V+':
} 9|'
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>;
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/** |#{- .r6Y]
* the basic page utils not including exception EQ4#fAM)
'eDJ@4Xm
handler 9]"S:{KSCn
* @param everyPage ac9qj
* @param currentPage v @:~mwy
* @param totalRecords kr%2 w
* @return page 2ck4C/ h
*/ pX@Si3G`
publicstatic Page createPage(int everyPage, int m23+kj)+VY
g3Z:{@m
currentPage, int totalRecords){ 7 _`L$<-n
everyPage = getEveryPage(everyPage);
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currentPage = getCurrentPage(currentPage); pe9@N9_5
int beginIndex = getBeginIndex(everyPage, d')-7C
;x-(kIiE
currentPage); #? dUv#
int totalPage = getTotalPage(everyPage, z"lqrSJ:
/RGNAHtIi
totalRecords); @}WNKS&m
boolean hasNextPage = hasNextPage(currentPage, r!7 Y'|
3{KR
{B#L
totalPage); ] /+D^6
boolean hasPrePage = hasPrePage(currentPage); %?bcT[|3
u_PuqRcs
returnnew Page(hasPrePage, hasNextPage, 0n.S,3|
everyPage, totalPage, f|U0s
currentPage, baee?6
+iy7e6P
beginIndex); ` @8`qXg
} XAPYpBgm
Ur^j$B}
privatestaticint getEveryPage(int everyPage){ @9Q2$
return everyPage == 0 ? 10 : everyPage; 'B_\TU0
O
} qos`!=g?
1~J5uB 4
privatestaticint getCurrentPage(int currentPage){ %a];
return currentPage == 0 ? 1 : currentPage; 5!Bktgk.
} ZU^IH9
2edBQYWd
privatestaticint getBeginIndex(int everyPage, int MM?`voj~`p
Y>BP?l
currentPage){ m
41t(i
return(currentPage - 1) * everyPage; 'Hw4j:pS
} nBN&.+3t
q@n^ZzTx
privatestaticint getTotalPage(int everyPage, int AVG>_$<
`2`fiKm
totalRecords){ JS2nXs1
int totalPage = 0; ,m^;&&
B<7/,d'
if(totalRecords % everyPage == 0) e*C6uz9N
totalPage = totalRecords / everyPage; 1DE@N1l
else ,Ol ( piR
totalPage = totalRecords / everyPage + 1 ; \hlR]m!C
/-4$7qd
return totalPage; oE?QnH3R
} 3xNMPm
Q$ri=uB;+
privatestaticboolean hasPrePage(int currentPage){ >`'O7.R
return currentPage == 1 ? false : true; e}0:"R%E
} p_{("zQ
O oSb>Y/4
privatestaticboolean hasNextPage(int currentPage, A5fwAB
Ue*C>F
int totalPage){ #eK=
return currentPage == totalPage || totalPage == ow6*Xr8eQ
]JE TeZ^/
0 ? false : true; ar.AL'
} |>2FRPK
%+-C3\'
{f/ ]5x(_
} Jq
]:<TQ
ZDx@^P y
V-!"%fO.s
Kmz7c|
DNkWOY#{
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。 eKN$jlg
J:j<"uPm
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 F7MzCZvu
]XA4;7
做法如下: ,FZT~?
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 06*rWu9P3
`zpbnxOL$T
的信息,和一个结果集List: ^YvB9XN
java代码: UsQ4~e 4-
kforu!C
@kFu*"
/*Created on 2005-6-13*/ ~D[?$`x:
package com.adt.bo; R?66b{O
DJ@|QQ
import java.util.List; l4y{m#/
pS[KBQ"F
import org.flyware.util.page.Page; {/<6v. v
7=XL!:P
/** %7hB&[ 5
* @author Joa J*fBZ.NO
*/ kJQ#Wz|z]
publicclass Result { vuQ%dDxI
-e u]:4
private Page page; \5)h tL1F
:_kAl? eJ
private List content; J;$N{"M
wsU V;S*X%
/** "
=]
-%B
* The default constructor QK`i%TXJ
*/ P
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public Result(){ LjB;;&VCn
super(); 8Q{9>^
} l8h&|RY[
>q~l21dUi
/** ,Gk}"w
* The constructor using fields mTNVU@TY=
* `Y=WMNy
* @param page MZJ]Dwt]
* @param content &w8)* T
*/ clw%B
public Result(Page page, List content){ A"5z6A4WB
this.page = page; $,>@o=)_
this.content = content; b6(p
} ]iNEw9
3]&o*Ib1`_
/** evA/+F,&
* @return Returns the content. $_H`
*/ 6x)$Dl
publicList getContent(){
!R-z%
return content; F}GPZ=T;
} YC_5YY(k
!QI\Fz?
/** 8vSse
* @return Returns the page. YW@#91.
*/ W1B)]IHc
public Page getPage(){ 9[c%J*r
return page; 6r:?;j~l
} 2`GE
so$(_W3E,
/** S& #U!#@
* @param content ((tv2
* The content to set. z7M_1%DEx
*/ 7pA/
public void setContent(List content){ 2Qp Hvsl_
this.content = content; E{^ XlY
} Rm1A>1a:
A\_ |un%
/** NLPkh,T:
* @param page :j')E`#
* The page to set. &!aAO(g
*/ }]n$ %g(
publicvoid setPage(Page page){ +Q=1AXe
this.page = page; `LAR@a5i
} ##Q/I|
} [.hyZ}B
h_1T,f(
c gzwx
uXDq~`S
g,o?q:FL
2. 编写业务逻辑接口,并实现它(UserManager, '0y9MXRT
KDl_?9E5
UserManagerImpl) \)K^=jM
java代码: I):!`R.,
#_Z$2L"U
?m$a6'2-,J
/*Created on 2005-7-15*/ Uj+j}C
package com.adt.service; a22Mufl
P&m\1W(
import net.sf.hibernate.HibernateException; \<}&&SuH
f7h*Vu`>
import org.flyware.util.page.Page; t5)+&I2
-V,v9h^
import com.adt.bo.Result; Q+b
D}emd
+aF}oA&X[
/** ,QzL)W7
* @author Joa 7\*FEjRM]
*/ wC `+
publicinterface UserManager { / kt2c[9
Y]]}*8
public Result listUser(Page page)throws pwwH<0[
Y6,Rj:8
HibernateException; 1+-_s
+xc'1id@[
} 7eWk7&Xul
Mu'8;9_6
pdJ/&ufh
;nC.fBu
=@k%&* Y?
java代码: 3^s/bm$g
Bs?7:kN(
1]orUF&_
/*Created on 2005-7-15*/ 54
> -
package com.adt.service.impl; 7jnIv];i
%dQxJMwj
import java.util.List; +f*OliMD
^c:Fy+fb
import net.sf.hibernate.HibernateException; meN2ZB?Y
Z|%_oR~b|
import org.flyware.util.page.Page; Hwo$tVa:=
import org.flyware.util.page.PageUtil; Y"OG@1V;8
GA7}K:LP'k
import com.adt.bo.Result; Y0D}g3`
import com.adt.dao.UserDAO; ynA|}X
import com.adt.exception.ObjectNotFoundException; DW)2 m;
import com.adt.service.UserManager; ~T) Q$
u,}{I}x_
/** ~ek$C
* @author Joa z<B8mB
*/ `--TP
publicclass UserManagerImpl implements UserManager { A^q[N
j"AU z)x
private UserDAO userDAO; 7 ^w >Rj
#j *d^j&
/** PJ='tJDj
* @param userDAO The userDAO to set. 5/po2V9)
*/ ?nP*\8
publicvoid setUserDAO(UserDAO userDAO){ [s&$l G!
this.userDAO = userDAO; V+I|1{@i0
} t|~YEQ
o.q/O)'V u
/* (non-Javadoc) :n /@z4#
* @see com.adt.service.UserManager#listUser |&Ym@Jyj
6252N]*
(org.flyware.util.page.Page) wn)JXR
*/ ~I{n^Q/a
public Result listUser(Page page)throws +-E~6^>
1Bpv"67
HibernateException, ObjectNotFoundException { <{~6}6o
int totalRecords = userDAO.getUserCount(); ;j4?>3
if(totalRecords == 0) i;!H!-sM
throw new ObjectNotFoundException ID#I`}h.k
765p/**
("userNotExist"); -?(E_^ng
page = PageUtil.createPage(page, totalRecords); r#xg#u oj
List users = userDAO.getUserByPage(page); 0_CN/5F
returnnew Result(page, users); i\W/C
} ` AY_2>7
(PfqRk1Y
}
>3c@x
cI=(\pC
bf9a1<\
r2k2%nI-J
e^ v.)
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 jg?x&'u\)
{J^lX/D
询,接下来编写UserDAO的代码: d6W SL;$
3. UserDAO 和 UserDAOImpl: c+2FC@q{l
java代码: b$Vz2Fzx
/%Nr?V
?(R]9.5S
/*Created on 2005-7-15*/ JGuN:c$
package com.adt.dao; %'[&U# -
1 5A*7|
import java.util.List; rL}YLR
92^w8Z.
import org.flyware.util.page.Page; -YsLd 9^4
Nj?/J47?,
import net.sf.hibernate.HibernateException; qu|B4?Y/CR
C:Hoq(
/** A]XZnQ
* @author Joa W^G>cC8.L
*/ s+Q~~]HJM
publicinterface UserDAO extends BaseDAO { >Jp:O
7
r3>i+i42
publicList getUserByName(String name)throws 8jyG"%WO
F{UP;"8'
HibernateException; e@IA20
d9q(xZ5
publicint getUserCount()throws HibernateException; :H c0b=
5|1T}Z#;
publicList getUserByPage(Page page)throws zToq^T
l&[;rh
HibernateException; -=(!g&0
*k19LI.5
} hXA6D)
]8T!qS(UJd
sVl-N&/
VZ\B<i
A,`8#-AX
java代码: VqS#waNrx
kcQ'$<Mz<
FXs*vg`
/*Created on 2005-7-15*/ 4n4?4BEn
package com.adt.dao.impl; hiUD]5Kp
0@EwM
import java.util.List; mdw7}%5V
z(H^..<!5
import org.flyware.util.page.Page; _%GGl$kH
/IsS;0K%L
import net.sf.hibernate.HibernateException; i@4~.iZ8
import net.sf.hibernate.Query; ?2oHZ%G
E<c9#I=
import com.adt.dao.UserDAO; HcqfB NM
lIProF0
/** 1Uqu>'
* @author Joa F}=aBV|-
*/ C?2'+K
public class UserDAOImpl extends BaseDAOHibernateImpl $_x^lr
mVR P~:+
implements UserDAO { *guoWPA|Ij
Lliqj1&
/* (non-Javadoc) gmm|A9+tv
* @see com.adt.dao.UserDAO#getUserByName >Bgw}PI
X@f "-\
(java.lang.String) $ mI0Bk
*/ vPD]hs
publicList getUserByName(String name)throws nH<eR)0
'z[Sp~I\
HibernateException { SGe^ogO"v
String querySentence = "FROM user in class 3Oi
nK['
VhNz8)
com.adt.po.User WHERE user.name=:name"; Iyyh!MVF
Query query = getSession().createQuery u&n'
ITH
uh?>-
]r`
(querySentence); BN4_:
query.setParameter("name", name); l'3pQ;
return query.list(); zA1lca0HK
} -*XCxU'
nI*v820,
/* (non-Javadoc) -k"^o!p
* @see com.adt.dao.UserDAO#getUserCount() }|XtypbL
*/ Q^#;WASi
publicint getUserCount()throws HibernateException { B|&"#Q
int count = 0; EcCFbqS4W
String querySentence = "SELECT count(*) FROM IqD_GL)Ms
M-giR:,
user in class com.adt.po.User"; `3hSLR
Query query = getSession().createQuery |0%+wB
X3V'Cy/sy
(querySentence); fF V!)Zj
count = ((Integer)query.iterate().next iySRY^
>mjNmh7
()).intValue(); YxP@!U9dE,
return count; <NuUW9+
} `YIf_a{
Yk5}`d!:
/* (non-Javadoc) 48*Do}l]
* @see com.adt.dao.UserDAO#getUserByPage u6bXv(
o!!yd8~*r
(org.flyware.util.page.Page) A$a1(8H
*/ n2fbp\ I
publicList getUserByPage(Page page)throws (owrdPT!
!OuWPH.
:
HibernateException { &Y^WP?HS
String querySentence = "FROM user in class yfC^x%d7G
1hziXC0WY
com.adt.po.User"; th&[Nt7
Query query = getSession().createQuery P[k$vD
%C=]1Q=T)
(querySentence); pe{;~-|6
query.setFirstResult(page.getBeginIndex()) y})70w@+_
.setMaxResults(page.getEveryPage()); g=$1cC+(
return query.list();
''Cay0h
} ,qYJioWX
eR3$i)5
} MKWyP+6`
4M^G`WA}t9
D7S'*;F
`8Lo {P
Z%n(O(^L
至此,一个完整的分页程序完成。前台的只需要调用 j7)Ao*WN
b&5lY p"d
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]C:l,I
I*`* Q$
的综合体,而传入的参数page对象则可以由前台传入,如果用 8{Fsm;UsY
dH^ <t,v
webwork,甚至可以直接在配置文件中指定。 ,-OCc!7K
~fo6*g:f1
下面给出一个webwork调用示例: ]Qe{e3p;
java代码: b@2J]Ay E*
jvQ*t_L
H8'Z#"h
/*Created on 2005-6-17*/ Q;D0<Bv
package com.adt.action.user; U_{Ux2
<!pvqNApg
import java.util.List; u3o#{~E/#
&|`C)6[C
import org.apache.commons.logging.Log; kGN+rHo
import org.apache.commons.logging.LogFactory; "&%#!2
import org.flyware.util.page.Page; E]6z8juO6
'gt-s547
import com.adt.bo.Result; I'@Ydt2
import com.adt.service.UserService; Q(\4]i< S
import com.opensymphony.xwork.Action; qVs\Y3u(
w$u3W*EoU^
/** B.L]Rk\4
* @author Joa b? j< BvQ
*/ U2%.S&wS,e
publicclass ListUser implementsAction{ "5,
zdp/|"D!
privatestaticfinal Log logger = LogFactory.getLog %:2+
o'
_{ZqO;[u
(ListUser.class); % =BMZRn
EKzAd
private UserService userService; r]0
lo-
5A4&+rdU
private Page page; 0p@k({] <
s|NjT
privateList users; ?PyG/W
eBJUv]o %
/* A.5i"Ci[ie
* (non-Javadoc) /AQMFx4-5
* oy;K_9\
* @see com.opensymphony.xwork.Action#execute() =2
*rA'im
*/ V$uk6#
publicString execute()throwsException{ R+7oRXsu
Result result = userService.listUser(page); yZWoN&
page = result.getPage(); 1u|Rl:Q
users = result.getContent(); ZZyDG9a>7
return SUCCESS; j6g[N4xr
} A mwa)
{H{X[p8
/** #-GJ&m8
* @return Returns the page. 7YAIA%8
*/ s-S}i{Z!
public Page getPage(){ SM^-Z|d?
return page; ai0Ut
} +nT'I!//
R9!Uo
/** TET`b7G
* @return Returns the users. 0Ld@H)
*/ JO@|*/mL
publicList getUsers(){ LE%7DW(
return users; _H^^y$+1
} SKW%X8
L-9~uM3@\
/** ys#i@
* @param page x+G0J8cW
* The page to set. 9RWkm%?
*/ -$,%f?
publicvoid setPage(Page page){ 3bNIZ#`|MB
this.page = page; VG>vn`x>a
} Z,.G%"i3C
?r2 #.W
/** $8crN$ye
* @param users 0=="^t_
* The users to set. c1xrn4f@a
*/ aIXdV2QS
publicvoid setUsers(List users){ )$Z=t-q
this.users = users; E~kG2x{a
} ^xZ
e2@
$v b,P(
/** c~o+WI
Ym
* @param userService M+!x}$&v
* The userService to set. :>81BuMvg
*/ b,IocD6v;P
publicvoid setUserService(UserService userService){ .{S8f#p9T
this.userService = userService; Tb1U^E:
} wap3Kd>MP
} _e7-zg$/
[qoXMuC|P
P6Mhbmt9*
7FF-*2@
_qWliw:0#
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Gc$gJnQio
j.:h5Y^N
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
x3zj?-
D\ H/
么只需要: 4c+$%pq5
java代码: m~'? /!!
mw^7oO#
qSx(X!YS
<?xml version="1.0"?> dC1V-x10ju
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork bOI3^T
J/A[45OD
1.0//EN" "http://www.opensymphony.com/xwork/xwork- syzdd
an
4"=Vq5
1.0.dtd"> _3Cn{{ A0
Y$-3v.
<xwork> 9,]5v+
?tg
y|
<package name="user" extends="webwork- `O6:t\d@
k6Cn"2q <
interceptors"> H7[6yh
fj ,m
<!-- The default interceptor stack name KL'zXkS
<:|3rfm#
--> tU/k-W3X
<default-interceptor-ref >ulY7~wUv
^S#t|rN
name="myDefaultWebStack"/> G9g6.8*&
},[;O^Do^{
<action name="listUser" /VHi>
H UWxPIu
class="com.adt.action.user.ListUser"> .C]cK%OO
N
<param 3^=+gsc
jKIc09H|
name="page.everyPage">10</param> 4Tct
<result V|MY!uV
ZlKw_Sq:
name="success">/user/user_list.jsp</result> W9zE{)Sc~
</action> iK_c.b
5y4u5Tm-%
</package> y/c%+Ca/
kWj
\x|E
</xwork> ,572n[-q
X%9*O[6{
XUV!C7
i.1U|Pi
DDd|T;8
StYzGJ
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 VK3it3FI>3
o5aLUWi-
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。 c3
&m9zC
;pRcVL_4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 T{vR,
)$x_!=@1
$(q>mg:H
y 0ckm6^
P|jF6?C
我写的一个用于分页的类,用了泛型了,hoho =GR'V
Dmdy=&G
java代码: ;2giZ\
f*xpE`&
<JI&
{1
package com.intokr.util; 1MA@JA:T
G.U5)4_^
import java.util.List; Rn+4DcR
1QJBb \
/** 7k=fZ$+O
* 用于分页的类<br> mW`oq
* 可以用于传递查询的结果也可以用于传送查询的参数<br> g2p"LWex-
* ;Pb8YvG1$
* @version 0.01 dX
)W0
* @author cheng '7Ig.K&
*/ }{],GHCjQ
public class Paginator<E> { G\iyJSj[P
privateint count = 0; // 总记录数 u2sR.%2U<
privateint p = 1; // 页编号 rU#li0
>
privateint num = 20; // 每页的记录数 mxqG-*ch-
privateList<E> results = null; // 结果 ?n'OF pd
%kU'hzLg
/** PoD^`()FR{
* 结果总数 '=cKU0
G #
*/ `EMi0hm&H
publicint getCount(){ *i<\iMoW
return count; S-Ai3)t6
} I+,SZ]n
$EBb"+Y'T
publicvoid setCount(int count){ Jfg7\&|
this.count = count; NO>k
} ]7qiUdxt:
fUcLfnr
/** )fh0&Y; R
* 本结果所在的页码,从1开始 et$uP
* qSiWnN8D
t
* @return Returns the pageNo. H}b\`N[nr
*/ -fIc4u[
publicint getP(){ IjZ@U%g@;
return p; !Ua&0s%
} 0\a8}b||
[N|xzMe
/** !0fI"3P@r
* if(p<=0) p=1 x,Y5U+]E
* |pWaBh|r
* @param p # .q#OC
*/ u.6P-yh
publicvoid setP(int p){ u3dsQU
if(p <= 0) x0Bw{>Q
p = 1; ,86K
this.p = p; /)V4k:#b
} fA8ozL T
WD?Jk9_F
/** T{-2fp8r[
* 每页记录数量 3eg5oAZ)G8
*/
^Omfe
publicint getNum(){ |f NMs
return num; C+l?k2
} HZ\k-!2
IL2r9x%
/** zk>h u<_
* if(num<1) num=1 |< N frz
*/ ]*ov&{'
publicvoid setNum(int num){ elbG\qXBp
if(num < 1) !A[S6-18%-
num = 1; c#\-%h
this.num = num; ac6*v49
} pT=2e&
xv0M
/** 4r*Pa(;y
* 获得总页数 5G?.T?
*/ W/v|8-gcK
publicint getPageNum(){ RG?MRxC
return(count - 1) / num + 1; ,h!X k
} aJ2H.E
wD=am
/** c$#GM57V
* 获得本页的开始编号,为 (p-1)*num+1 P^(.tr3t
*/ &|=?acv
publicint getStart(){ UB&2f>
return(p - 1) * num + 1; :QKb#4/8;
} o>!JrH
N5\{yV21",
/** pbdF]>\
* @return Returns the results. #`j][F@N
*/ /c^e&D
publicList<E> getResults(){ T~:_}J
return results; dzxI QlP
} r{V.jZ%p'Z
h[H%:743
public void setResults(List<E> results){ Ej|A
; &E
this.results = results; m0Z7N5v)
} 1NGyaI
~'[jBn)
public String toString(){ 3M$X:$b
StringBuilder buff = new StringBuilder X2P``YFV{
{_as!5l
(); b_ JWnh
buff.append("{"); bm6hZA|
buff.append("count:").append(count); YZ*{^'
buff.append(",p:").append(p); 3k{c$x}
buff.append(",nump:").append(num); O0zi@2m?B
buff.append(",results:").append VIYV92[
wWFW,3b
(results); >p |yf.G
buff.append("}"); xSOoIsL[
return buff.toString(); 2H>aC
wfX
} H%~Q?4
6JWGu/A
} U6a zhi&,
!5E9sk{)
*2#FRA#q