Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 R]"Zv'M(AM
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 !l'nX
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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 ^z
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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 :\;9y3
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分页支持类: ('z=/"(l
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java代码: y_WC"
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package com.javaeye.common.util; zdP?HJ=F
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import java.util.List; 4!!|P
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publicclass PaginationSupport { D^r g-E[L
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publicfinalstaticint PAGESIZE = 30; 1]}\h]*
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privateint pageSize = PAGESIZE; 2f(`HSC'
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privateList items; r9f- [wC
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privateint totalCount; %`~4rf"7
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privateint[] indexes = newint[0]; &OU.BR>
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privateint startIndex = 0; |6AR!
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public PaginationSupport(List items, int lr&2,p<
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totalCount){ |1wZ`wGZ:L
setPageSize(PAGESIZE); m]DP{-s4
setTotalCount(totalCount); 5XA{<)$
setItems(items); wtnC^d$
setStartIndex(0); 3N 5b3F
} 6{PlclI !
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public PaginationSupport(List items, int dJD8c2G
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totalCount, int startIndex){ 1|Z!8:&pj
setPageSize(PAGESIZE); S+&Bf ~~D
setTotalCount(totalCount); CQm(N
setItems(items); &ywU^hBh
setStartIndex(startIndex); [oh0 )wzB
} RwptFO
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public PaginationSupport(List items, int -9z!fCu3
;4ETqi9
totalCount, int pageSize, int startIndex){ m_g2Cep
setPageSize(pageSize); =;?afUj
setTotalCount(totalCount); Dm0Ts~
setItems(items); \_J;i[
setStartIndex(startIndex); $@(+"
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}
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publicList getItems(){ Ga1(T$|H
return items; Q,m1mIf
} nL@(|nJ[
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publicvoid setItems(List items){ )tW0iFY
this.items = items; %DR8M\d1~H
} W2F *+M
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publicint getPageSize(){ txp^3dZ`^
return pageSize; 5b5Hc Inu
} =AIeYUh
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publicvoid setPageSize(int pageSize){ kMP3PS
this.pageSize = pageSize; 'Wz`P#/
} r?j2%M\
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publicint getTotalCount(){ |)}&:xA%
return totalCount; 3BzC'nplm
} |s$w
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publicvoid setTotalCount(int totalCount){ f5ttQ&@FF
if(totalCount > 0){ N0_@=uE
this.totalCount = totalCount; 6I!B>V#U+
int count = totalCount / <*F!A' w2o
l1I\khS
pageSize; zD,K_HicI
if(totalCount % pageSize > 0) sm?V%NX&
count++; 'YTSakNJ}
indexes = newint[count]; ,\Uc/wR
for(int i = 0; i < count; i++){ ?hh#@61
indexes = pageSize * BDiN*.w5
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i; f~?4
} O
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}else{ .:/[%q{k
this.totalCount = 0; J[ 7Sf^r
} !<#,M9
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} fIwG9cR
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publicint[] getIndexes(){ p%ZOLoc)Y
return indexes; &\>. j|
} J-d>#'Wb|
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publicvoid setIndexes(int[] indexes){ 6s(.ul
this.indexes = indexes; c>.=;'2
} s9F{UN3
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publicint getStartIndex(){ _y5J]Yu`j
return startIndex; 8ZL9>"%l
} `),ACkU>U
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publicvoid setStartIndex(int startIndex){ R8N*. [
if(totalCount <= 0) bBg=X}9
this.startIndex = 0; ={[9kR i
elseif(startIndex >= totalCount) nv'YtmR
this.startIndex = indexes S\<nCkE^
teX)!N [
[indexes.length - 1]; 7;r Jr&.)
elseif(startIndex < 0) 4#Cm5xAt6
this.startIndex = 0; }!*CyO*
else{ dh K<5E
this.startIndex = indexes kG>m(n
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[startIndex / pageSize]; Vqp3'=No
} _;'<}a
} lOEB ,/P
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publicint getNextIndex(){ T%O2=h\} E
int nextIndex = getStartIndex() + wn/Y5
jeWI<ms
pageSize; =g{Hs1W
if(nextIndex >= totalCount) ;/ASl<t,
return getStartIndex(); /zg|I?$>Z4
else V(wANvH
return nextIndex; ~%?LFR'
} `EWQ>m+
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publicint getPreviousIndex(){ ?.Lq`~T`
int previousIndex = getStartIndex() - p5`={'>-
4Qj@:b
pageSize; _"h1#E
if(previousIndex < 0) jg\FD51$
return0; |"aop|
else WPDi)UX
return previousIndex; EYSBC",
} r^T+I3
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} %`\=qSf*
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抽象业务类 *('Vyd!n
java代码: bBY7^k
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/** )QW
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* Created on 2005-7-12 &~V6g(9
*/ tQ,3nI!|xF
package com.javaeye.common.business; dhV6r
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import java.io.Serializable; l#& \,T
import java.util.List; UO4z~
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import org.hibernate.Criteria; pM}n)Q!{3"
import org.hibernate.HibernateException; cv"Bhql
import org.hibernate.Session; 5
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import org.hibernate.criterion.DetachedCriteria; .f9&.H#
import org.hibernate.criterion.Projections; 8fA8@O}
import F4$9r^21r
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org.springframework.orm.hibernate3.HibernateCallback; k-I U}|Xz
import qo7jrY5G
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org.springframework.orm.hibernate3.support.HibernateDaoS 09J,!NN
jIjW +D`
upport; |Ge!;v
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import com.javaeye.common.util.PaginationSupport; thSXri?kl
r#B{j$Rw
public abstract class AbstractManager extends ."j=s#OC(
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HibernateDaoSupport { />O.U?
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privateboolean cacheQueries = false; Ws:+P~8
XGAR8=tic
privateString queryCacheRegion; eA-$TSWh
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publicvoid setCacheQueries(boolean =U}!+ 8f
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cacheQueries){ ql7N\COoq
this.cacheQueries = cacheQueries; q3ebps9^
} tS[%C)
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publicvoid setQueryCacheRegion(String -#
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queryCacheRegion){ TRFza}4:i
this.queryCacheRegion = X4/3vY
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queryCacheRegion; /J!~0~F
} dC?l%,W
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publicvoid save(finalObject entity){ rQ)I
getHibernateTemplate().save(entity); K<p)-q
} 9,$
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Q}
publicvoid persist(finalObject entity){ mV|Z5 =f
getHibernateTemplate().save(entity); Yq%r\[%*
} =~'y' K]
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publicvoid update(finalObject entity){ ,@aF#
getHibernateTemplate().update(entity); v(l:N@L
} 41c4Xj?'
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publicvoid delete(finalObject entity){ C:RA(
getHibernateTemplate().delete(entity); y|(?>\jBl
} 4K$_d,4`U
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publicObject load(finalClass entity, CPJ%<+4%b
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finalSerializable id){ ^F87gow%`B
return getHibernateTemplate().load 8:k-]+#o
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(entity, id); c
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} ,R=)^Gh{
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publicObject get(finalClass entity, zZiga q"
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finalSerializable id){ ?;DzWCL~9
return getHibernateTemplate().get BCt>P?,UO
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(entity, id); ]>,Lw=_[_
} B+[L/C}=;
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publicList findAll(finalClass entity){ b\C1qM4
return getHibernateTemplate().find("from Duq.`XO
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8fB8{
" + entity.getName()); te&p1F
} g4GU28 l
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publicList findByNamedQuery(finalString c@{M),C~E
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namedQuery){ }XfRKGQw
return getHibernateTemplate I~25}(IDZ"
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().findByNamedQuery(namedQuery); 6QNO#!;
} nOK1Wc%/'
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publicList findByNamedQuery(finalString query, Yw,LEXLY
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finalObject parameter){ e.]k4K
return getHibernateTemplate @WP%kX.?
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().findByNamedQuery(query, parameter); wZ/b;%I!
} :{~TG]4M
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publicList findByNamedQuery(finalString query, WP4"$W
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finalObject[] parameters){ >C/O >g
return getHibernateTemplate rG{,8*
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().findByNamedQuery(query, parameters); :6W* ;<o
} @vvGhJ1m`
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publicList find(finalString query){ :tX,`G
return getHibernateTemplate().find G/&Wc2k
t#=FFQOt
(query); |. LE`
} D*!9K8<o
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publicList find(finalString query, finalObject =B"^#n ;
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parameter){ I|)U>bV
return getHibernateTemplate().find F^X:5g~K
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(query, parameter); yQquGu
} >:f&@vwm
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public PaginationSupport findPageByCriteria fk(h*L|sI
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(final DetachedCriteria detachedCriteria){ WS1#i\0
return findPageByCriteria zN,2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); l6< bV#_qe
} KNqs=:i
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public PaginationSupport findPageByCriteria iU?xw@WR
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(final DetachedCriteria detachedCriteria, finalint l&uBEYx
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startIndex){ j~k+d$a
return findPageByCriteria YY
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$;B0x
(detachedCriteria, PaginationSupport.PAGESIZE, S/x CX!
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startIndex); 3V@!}@y,F6
} ?TY/'-M5
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public PaginationSupport findPageByCriteria yPVK>em5
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(final DetachedCriteria detachedCriteria, finalint Bngvm9k3
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pageSize, 31~Rs?~f(
finalint startIndex){ `6 ?.ihV
return(PaginationSupport) "UTAh6[3oD
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getHibernateTemplate().execute(new HibernateCallback(){ Jn)DZv8?
publicObject doInHibernate
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(Session session)throws HibernateException { m$B)_WW
Criteria criteria = Q7XlFjzcm
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detachedCriteria.getExecutableCriteria(session); L3y`*&e>
int totalCount = J|:Zs1.<d
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((Integer) criteria.setProjection(Projections.rowCount esK0H<]
C,nU.0
()).uniqueResult()).intValue(); SB=%(]S
criteria.setProjection ~oE@y6Q
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(null); c<]~q1
List items = 41NVF_R6J
@t<KS&
criteria.setFirstResult(startIndex).setMaxResults <F<jx"/)
6;#Rd|
(pageSize).list(); x$=""?dd
PaginationSupport ps = *1CZRfWI
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new PaginationSupport(items, totalCount, pageSize, hvOl9W>
{q|Om?@
startIndex); /'Q2TLy=
return ps; !\/J|~XZ
} ^Bu55q
}, true); ~dlpoT
} %rq/jC
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public List findAllByCriteria(final Ym$=^f]-
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DetachedCriteria detachedCriteria){ ]Ofs,U^
return(List) getHibernateTemplate ! ,&{1p
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().execute(new HibernateCallback(){ k07pI<a?
publicObject doInHibernate H/N4tWk"
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(Session session)throws HibernateException { C9L_`[9DO
Criteria criteria = YK%rTbB(
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detachedCriteria.getExecutableCriteria(session); W?X3 :1c9:
return criteria.list(); _q=ua;I&
} vk.P| Y-;
}, true); Am"e%|:
} I@q(P>]X9
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public int getCountByCriteria(final XN}^:j_2
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DetachedCriteria detachedCriteria){ }0~X)Vgm(
Integer count = (Integer) M*2
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getHibernateTemplate().execute(new HibernateCallback(){ ,v_NrX=f?
publicObject doInHibernate ")@#B=8+3^
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(Session session)throws HibernateException { E D^0t
Criteria criteria = z#^;'nnw
3 @%XR8ss
detachedCriteria.getExecutableCriteria(session); ]_43U` [#
return {3!E8~
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criteria.setProjection(Projections.rowCount aM YtWj
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()).uniqueResult(); DT vCx6:!
} p> g[: ~
}, true); fs0EbVDF
return count.intValue(); u7lO2C7
} ,-[z?dvO
} Fs&r^ [/b
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用户在web层构造查询条件detachedCriteria,和可选的 bX>R9i$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8]Q#P
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PaginationSupport的实例ps。 5i+cjT2
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ps.getItems()得到已分页好的结果集 `T{'ufI4B
ps.getIndexes()得到分页索引的数组 m UUNR,
ps.getTotalCount()得到总结果数 bE?X?[K
ps.getStartIndex()当前分页索引 wKKQAM6P1
ps.getNextIndex()下一页索引 xZA.<Yd^r
ps.getPreviousIndex()上一页索引 JJK-+a6cX
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,Oe:SZJ>
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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 $O%"[w
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一下代码重构了。 AEkjy h\
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我把原本我的做法也提供出来供大家讨论吧: 5Dzf[V^]`
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首先,为了实现分页查询,我封装了一个Page类: G"w
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java代码: mm;sf
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/*Created on 2005-4-14*/ tQas_K5
package org.flyware.util.page; IqiU
vn!5@""T
/** 7hTpjox2
* @author Joa U$Z<lx2P
* YxrMr9>l1
*/ sO}CXItC+j
publicclass Page { 2vh }:A_
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/** imply if the page has previous page */ QO^V@"N
privateboolean hasPrePage; fp*6Dv_
D<|$ZuB4
/** imply if the page has next page */ ,H%[R+)
privateboolean hasNextPage; s1h|/7gG
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/** the number of every page */ k%X
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privateint everyPage; O-[
c@Br_-
/** the total page number */ $v #
privateint totalPage; P;o{t
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/** the number of current page */ _GFh+eS}
privateint currentPage; heL`"Y2'y>
Arm'0)B>
/** the begin index of the records by the current ;i\N!T{>
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query */ (xHu@l!]
privateint beginIndex; ~^jPE)
,
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/** The default constructor */ "T{WOGU+
public Page(){ fgeh;cD
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} !+A%`m
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/** construct the page by everyPage LRts
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* @param everyPage $y&W:
* */ yvj /u
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public Page(int everyPage){ Y!_{:2H8p
this.everyPage = everyPage; *asv^aFpS
} :\JCxS=EW
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/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, |T@SlNi]
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NXFi*
int everyPage, int totalPage, g(9* !g
int currentPage, int beginIndex){ NLY=o@<
this.hasPrePage = hasPrePage; :CW^$Zvq
this.hasNextPage = hasNextPage; IycZ\^5 *-
this.everyPage = everyPage; Yi?bY
this.totalPage = totalPage; `
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this.currentPage = currentPage; "WuUMt
this.beginIndex = beginIndex; KD,3U/3
} wpuK?fP
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/** erW2>^My
* @return JR#4{P@A
* Returns the beginIndex. Y&j`HO8f
*/ ofV0L
publicint getBeginIndex(){ V%s7*`U
return beginIndex; :\P@c(c{^C
} XDJE]2^52?
U,#x\[3!Jt
/** fMg9h9U
* @param beginIndex lbda/Zx
* The beginIndex to set. n}.e(z_"
*/ qWheoyAB
publicvoid setBeginIndex(int beginIndex){ G|f9l?p
this.beginIndex = beginIndex; wQUl!s7M;
} Bh2l3J4X
olv?$]
/** k3qQU)
* @return (cOe*>L;
* Returns the currentPage. wpM2{NTP
*/ Kh\ 7%>K#
publicint getCurrentPage(){ >-I <`y-H
return currentPage; cl4z%qv*
} (l^7EpNs
B#S8j18M
/** ]}!@'+=
* @param currentPage \)No?fB
* The currentPage to set. >|A,rE^Ojt
*/ g~y0,0'j1\
publicvoid setCurrentPage(int currentPage){ HK/WO jr
this.currentPage = currentPage; BA:x*(%~
} )~wKRyQff
N9_* {HOy
/** NSz}
* @return ]##aAh-P4&
* Returns the everyPage. Sc[#]2 }
*/ ][S q^5`
publicint getEveryPage(){ 5q0L<GOrj
return everyPage; d=xjLbsZ
} 3&y-xZ u]
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/** iAz0 A
* @param everyPage "J"=<_?
* The everyPage to set. n[Q(q[ULV
*/ zP44
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publicvoid setEveryPage(int everyPage){ `E$vWZq}
this.everyPage = everyPage; o-=|}u]mz
} q}t]lD
%C
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/** }&vD(hX
* @return 5?^#v
* Returns the hasNextPage. $E@n;0P
*/ 32z4G =l
publicboolean getHasNextPage(){ 'V?FeWp
return hasNextPage; v*!N}1+J
} #uU(G\^T
UDJjw
/** _8.TPB]no
* @param hasNextPage [`@M!G.
* The hasNextPage to set. I,hw0e
*/ Ikdj?"+O
publicvoid setHasNextPage(boolean hasNextPage){ H0s*Lb
this.hasNextPage = hasNextPage; M[`[+5v
} ,1{qZ(l1
@mCe{r*`
/** a>OYJe
* @return J]U_A/f
* Returns the hasPrePage. ><}nZ7
*/ 5[4wN(
)
publicboolean getHasPrePage(){ *V kaFQZ$,
return hasPrePage; `TPIc
} ~pZ0B#K
J
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/** s>/Xb2\
* @param hasPrePage 1\fx57a\
* The hasPrePage to set. g)#?$OhP"
*/ )Dz]Pv]H'
publicvoid setHasPrePage(boolean hasPrePage){ U,WMP<5&
this.hasPrePage = hasPrePage; }!_z\'u
} P4#i]7%
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/** D>y5&`
* @return Returns the totalPage. $sY'=S
* $l*?Ce:
*/ >T]9.`xhK
publicint getTotalPage(){ I$.lFQ%(
return totalPage; HDV-qYD|O~
} C~T,[U
)vO"S
/** |~5cNm
* @param totalPage 1Rd|P<y
* The totalPage to set. U*~-\jN1pb
*/ oYN"L
publicvoid setTotalPage(int totalPage){ QQW}.>N
this.totalPage = totalPage; }B'-*)^|e{
} , ~
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} +A?P 4}
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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 {3
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个PageUtil,负责对Page对象进行构造: ^<!R%"o-
java代码: &lLk[/b
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/*Created on 2005-4-14*/ FQ4R>@@5
package org.flyware.util.page; g$C]ln>"9m
@TW:6v`
import org.apache.commons.logging.Log; Q3& ?28
import org.apache.commons.logging.LogFactory; V?*fl^f
):4)8@]5M
/** x1`w{5;C 2
* @author Joa [4C_iaE
* ~M*
UMF^
*/ h{o,*QL
publicclass PageUtil { O[$X36z
@i'D)6sC
privatestaticfinal Log logger = LogFactory.getLog 2 {WZ?H93a
?uc]Wgw"s
(PageUtil.class); v
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{?^ES*5
/** > .}G[C
* Use the origin page to create a new page c{to9Lk.#
* @param page X&aQR[X
* @param totalRecords H @zZ[
* @return s\3]0n9
*/ o$->|k
publicstatic Page createPage(Page page, int c]VK%zl
Ow1+zltgj-
totalRecords){ p cUccQ
return createPage(page.getEveryPage(), lMW6D0^
E)Qg^DHP/
page.getCurrentPage(), totalRecords); aBQ --Sz
} cEp/qzAiD%
g3vbskY|
/** %#4;'\'5
* the basic page utils not including exception NR&a
er
=&-.] |t
handler _}\KC+n8
* @param everyPage HW_2!t_R
* @param currentPage uCW}q.@4
* @param totalRecords &{WEtaXaa
* @return page *3RD\.jPX
*/ j&.JAQ*2;
publicstatic Page createPage(int everyPage, int 6,CK1j+tZ
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currentPage, int totalRecords){ A ?~4Pe
everyPage = getEveryPage(everyPage); V^.Z&7+E`_
currentPage = getCurrentPage(currentPage); :+^`VLIf
int beginIndex = getBeginIndex(everyPage, >4>.
Ycp
MD1d
currentPage); #/`MYh=!W
int totalPage = getTotalPage(everyPage, h9c7P@29
yYk?K<ou
totalRecords); 3\<(!yY8
boolean hasNextPage = hasNextPage(currentPage, Um/ g&k
|QH )A
totalPage); \q-["W34
boolean hasPrePage = hasPrePage(currentPage); )d
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RKs_k`N0
returnnew Page(hasPrePage, hasNextPage, -Vg0J6x
everyPage, totalPage, JKXIxw>q
currentPage, N9Fu
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beginIndex); %HZ!s
`w_
} \gZjq]3
}2?-kj7
privatestaticint getEveryPage(int everyPage){ Tc;BE
return everyPage == 0 ? 10 : everyPage; -cXVkH{
} 7x
|Pgu(
Z q}Cl'f
privatestaticint getCurrentPage(int currentPage){ +w3k_^X9c
return currentPage == 0 ? 1 : currentPage; =)6|lz^
} vs.}Bou]
T:j!a{_|
privatestaticint getBeginIndex(int everyPage, int DGAg#jh
~Oj-W6-+&,
currentPage){ a)L=+Z
return(currentPage - 1) * everyPage; [;INVUwG^
} %}Ob~m>P
CH h6Mnw
privatestaticint getTotalPage(int everyPage, int vC5 (
}5;3c %
totalRecords){ YC~kq?
int totalPage = 0; p@xK`=Urb
+@oo8io
if(totalRecords % everyPage == 0) b{JxTT}03
totalPage = totalRecords / everyPage; [Hp"a^~r|
else QW%BKF!
totalPage = totalRecords / everyPage + 1 ; {I_I$x_
_RzcMX
return totalPage; nxYp9,c"
} !;C *Wsp}
~rU{Q>c
privatestaticboolean hasPrePage(int currentPage){ fL1EQ)
return currentPage == 1 ? false : true; rU1{a" {
} qg@Wzs7c~
VlFDMw.4.+
privatestaticboolean hasNextPage(int currentPage, Z,Tv8;
4mzWNr>fb
int totalPage){ .!J,9PE
return currentPage == totalPage || totalPage == wq&TU'O
PizPsJ|&
0 ? false : true; |LDo<pE*V4
} Z66@@?`
68LB745
APksY!
} ^Ru/7pw5
3$`qy|=zO
MoP0qNk
rx#\Dc}
[0e}%!%M
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 aTy&"
q,a|lH
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 4RqOg1
Z*|qbu)
做法如下: Qy @r&
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 d98ZC+q
yVM
1W"Q
的信息,和一个结果集List: GZ];U]_
java代码: hQfxz,X
r`L$[C5I
K G~fDb
/*Created on 2005-6-13*/ =ITMAC\
package com.adt.bo; ^kMgjS}R
ZIx,?E+eJ
import java.util.List; #9Z*.
)S|}de/a2
import org.flyware.util.page.Page; Ui46p
;
. c]0
/** PU^Z7T);
* @author Joa ,g$N
*/ zRJopcE<
publicclass Result { (6G5UwSt
S0~F$mP'
private Page page; >w?O?&Q$
'+|{4-V
private List content; fV_(P_C
![iAALPNl
/** {q"l|Oe
* The default constructor
M>~jLu0@
*/ 9\i,3:Qc
public Result(){ q7wd9 6G:
super(); >b0e"eGt
} pVw)"\S%
K{HRjNda#
/** 8lt P)K4
* The constructor using fields kO\(6f2|x
* M,PZ|=V6a
* @param page H.Z:at5n
* @param content R {+Rvk
*/ y8wOJZ<K
public Result(Page page, List content){ \sF}NBNT@
this.page = page; >0SF79-RE
this.content = content; z$`=7 afp
} lyx
p:
Hi9 ;i/
/** z8mR< q%`
* @return Returns the content. >\$qF
*/ p/'C
v
publicList getContent(){ BJk\p.BVN
return content; %n9}P ,
?
} Om{[ <tL
![:S~x1
/** =[?2'riI
* @return Returns the page. :j
vx-jQ
*/ v)+wr[Qs
public Page getPage(){ ~c :e0}
return page; C&3#'/&
} or~o'
< 7zyRm@S
/** \y:
0+s/
* @param content {`KgyCW:
* The content to set. i,FG?\x@
*/ J~DP*}~XK
public void setContent(List content){ @C7S^|eo
this.content = content; x-U:T.+{
} @| %t<{y^I
CjOaw$s
/** av gGz8
* @param page (Y'rEc#H&z
* The page to set. =5%jKHo+9z
*/ X`:(-3T
publicvoid setPage(Page page){ ,^,Vq]$3
this.page = page; {j,bV6X
} omECes)
} g84~d(\?
?;|$R
]BP/KCjAI<
doP4N6
GfJm&'U&
2. 编写业务逻辑接口,并实现它(UserManager, )(\5Wk9(
gUL`)t\} *
UserManagerImpl) fbwo2qe@K
java代码: ^P:9iu)+]~
2j4VW0:
~{Tus.jk
/*Created on 2005-7-15*/ 2[9hl@=%
package com.adt.service; ')bx1gc(?
REoFP;H~
import net.sf.hibernate.HibernateException; E^1uZI\z
{TzKHnP
import org.flyware.util.page.Page; z mrk`o~
#g{ZfO[#
import com.adt.bo.Result; 5p94b*l
AvEJX0"\df
/** cm-cwPAh
* @author Joa 6rt.ec(
*/ <R*.T)Z 1
publicinterface UserManager { }3lM+]pf
-:a
9'dT
public Result listUser(Page page)throws lx U}HM
ub+>i
HibernateException; S=krF yFw
3,oFT
} _
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T9RR.
ng
G:c)e,pD
R7ZxS
C%}FVO\c
java代码: w;}P<K
'<>pz<c
Rc0OEs%7P
/*Created on 2005-7-15*/ V_Wv(G0-\
package com.adt.service.impl; s7(mNpo
Z7K;~*
import java.util.List; B6MMn.
)(PA:j
import net.sf.hibernate.HibernateException; %:N5k+}
mAk)9`f/
import org.flyware.util.page.Page; y*vs}G'W
import org.flyware.util.page.PageUtil; z1T.\mzfX
;5PXPpJ
import com.adt.bo.Result; -XkCbxZ
import com.adt.dao.UserDAO; S,n*1&ogj
import com.adt.exception.ObjectNotFoundException; K> lA6i7?
import com.adt.service.UserManager; 5``/exG>
vbmi_[,U
/** HB||'gIC
* @author Joa &]ts*qCEL
*/ 9y>dDNM\<
publicclass UserManagerImpl implements UserManager { owmV7E1
3-lJ] 7OT
private UserDAO userDAO; P`@d8%*;
C6M|A3^T
/** {tOu+zy
* @param userDAO The userDAO to set. rNO'0Ck=
*/ ">v76%>Z7
publicvoid setUserDAO(UserDAO userDAO){ F7Mf>."
this.userDAO = userDAO; 5T:e4U&
} (5cc{zKtR
-,uTAk0+@
/* (non-Javadoc) r0+lH:G*q
* @see com.adt.service.UserManager#listUser jdK~]eld=
?k TVC
(org.flyware.util.page.Page) iyB02\d
*/ Qo4]_,kR
public Result listUser(Page page)throws dPc*!xrq
_<6
^r
HibernateException, ObjectNotFoundException { A0m
int totalRecords = userDAO.getUserCount(); 9s>q4_D
if(totalRecords == 0) aqQ
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throw new ObjectNotFoundException cV\(Z6u
@i'RIL}
("userNotExist"); ^ r-F@$:.
page = PageUtil.createPage(page, totalRecords); P(l$5x]g,
List users = userDAO.getUserByPage(page); $]2srRA^A
returnnew Result(page, users); f*,jhJ_I
} ,|D_? D)U
3k.{gAZKh
} '-oS=OrZ
~Z9Eb|B
\T`InBbf
_PLY<i2vr
9t:F![rg
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {Fs}8\ z
9UsA>m.
询,接下来编写UserDAO的代码: 'r~,~AI
3. UserDAO 和 UserDAOImpl: cXU8}>qY7
java代码: N:?UA
7I;xRo|
|5oK04<
/*Created on 2005-7-15*/ #?\$*@O
package com.adt.dao; H.*:+
`Fnl<C<
import java.util.List; H=Scrvfx
Q97F5ru6
import org.flyware.util.page.Page; K&Ner(/X`6
sL" h
import net.sf.hibernate.HibernateException; me:~q#k
5b> -t#N,
/** $mdmuUIy-3
* @author Joa O'm><a>8
*/ Fa<>2KkOr
publicinterface UserDAO extends BaseDAO { i[_(0P+Da
~e*3_l>9
publicList getUserByName(String name)throws R=
,jqW<
"yaz!?O>
HibernateException; mApn[)?tv
g_X-.3=2K
publicint getUserCount()throws HibernateException; 0U|t@&q
MDV<[${
publicList getUserByPage(Page page)throws !%MI9Ok
v:\8
HibernateException; Vw-,G7v&E
~o{GQ>
} paKur%2u
kw)("SQ
mzw`{Oy>L
mj{B_3b5
K[wny0 (
java代码: m=Mb'<
R[_Q}W'HG
5k:SD7^b
/*Created on 2005-7-15*/
Lk%`hsv
package com.adt.dao.impl; 42/MBP`\Y
-M]B;[^
import java.util.List; rU6F$I=
` wI$
import org.flyware.util.page.Page; `iHyGfm
F}1h
import net.sf.hibernate.HibernateException; %G0J]QY{(x
import net.sf.hibernate.Query; 7gWT[
vEy0DHEE
import com.adt.dao.UserDAO; Eep~3U
0Q7teXRM
/** vHJOpQmt~
* @author Joa \;XDPC j
*/ |>^5G@e
public class UserDAOImpl extends BaseDAOHibernateImpl {c
:7:
WCNycH+1
implements UserDAO { 4nsc`Hu
G2$<Q+UYs?
/* (non-Javadoc) # &,W x
* @see com.adt.dao.UserDAO#getUserByName ^C=dq(i=[
n~"qbtp}
(java.lang.String) *S xDwN
*/ !hs33@*u~
publicList getUserByName(String name)throws $e~MKLd
kzE<Y
HibernateException { 4,,DA2^!
String querySentence = "FROM user in class 8Y]% S9.
|,bP`Z
com.adt.po.User WHERE user.name=:name"; 6i+<0b}!/
Query query = getSession().createQuery z*a-=w0
Sj ly]
(querySentence); t[e]AU[}
query.setParameter("name", name); PglSQ2P
return query.list(); z''ejq
} eMV{rFmT
$`A{-0=x\U
/* (non-Javadoc) 2Z-[x9t
* @see com.adt.dao.UserDAO#getUserCount() r|63T%q!
*/ 0 <E2^
publicint getUserCount()throws HibernateException { ZEp>~dn;
int count = 0; "{S6iH)]8
String querySentence = "SELECT count(*) FROM v<Ywfb
\.aKxj5
user in class com.adt.po.User"; /1v:eoF;
Query query = getSession().createQuery iT;Ld $!{f
=@nE:uto]
(querySentence); d,b]#fj
count = ((Integer)query.iterate().next 3(Ns1/;?,
}[{9u#@#
()).intValue(); yH(3 m#
return count; ~,_@|,)
} }rvX}
AdpJ4}|0
/* (non-Javadoc) 4ClSl#X#i
* @see com.adt.dao.UserDAO#getUserByPage oTRidG
v, CWE
(org.flyware.util.page.Page) No8-Hm
*/ S0Ur{!9\#^
publicList getUserByPage(Page page)throws 27+~!R~Yw
cij8'("+!
HibernateException { T, +=ka$
String querySentence = "FROM user in class y^e3Gyk
aX~Jk >a0
com.adt.po.User"; !>"fDz<w`
Query query = getSession().createQuery mrq,kwM
[7Q%c!e$ *
(querySentence); op@=0d??
query.setFirstResult(page.getBeginIndex()) jXVvVv
.setMaxResults(page.getEveryPage()); fLpWTkr0
return query.list(); +J85Re `
} em95ccs'-
/N({"G'
} :.tL~%
q
RH:vd|q+
x#5vdBf
oeZUd}P
$bD`B'5
至此,一个完整的分页程序完成。前台的只需要调用 1l/t|M^I
Z^}[CQ&Am
userManager.listUser(page)即可得到一个Page对象和结果集对象 (/0dtJ
Fg 8lX9L
的综合体,而传入的参数page对象则可以由前台传入,如果用 QFnpp\K
^Zp
webwork,甚至可以直接在配置文件中指定。 mo3A *|U
m[(_fOd
下面给出一个webwork调用示例: eM
5#L,Y{
java代码: MRw4?HqB
_Rb2jq(&0
&XdTY +
/*Created on 2005-6-17*/ $}r.fji,c
package com.adt.action.user; ~#4FL<W
o$Ylqb#
import java.util.List; 3u/AqL
P;@j
import org.apache.commons.logging.Log; !Vg=l[
import org.apache.commons.logging.LogFactory; c{dabzLy
import org.flyware.util.page.Page; \gkhSLq
Xz)qtDN|(
import com.adt.bo.Result; k0O5c[j
import com.adt.service.UserService; (X
Oz0.W
import com.opensymphony.xwork.Action; '.;{"G.@'
_9t1aP5
/** ^iBIp#
* @author Joa y 3o3 G
*/ <&3aP}
publicclass ListUser implementsAction{ 7i{(,:
m(?{#aaq
privatestaticfinal Log logger = LogFactory.getLog 2IE\O8b
T&MhSJf#
(ListUser.class); HzKY2F(,
p}h.2)PO
private UserService userService; ;@Fb>lBhX
[>r0
(x&.
private Page page; +-(,'slov
;3wO1'=
privateList users; nw%9Qw
uSRhIKy
/* })P!7t
* (non-Javadoc) a*LfT<hmU3
* e3W~6P
* @see com.opensymphony.xwork.Action#execute() z'$1$~I
*/ @v^j<B
publicString execute()throwsException{ [:#K_EI5%
Result result = userService.listUser(page); aA52Li
page = result.getPage(); &mmaoWR
users = result.getContent(); kyvl>I0q@
return SUCCESS; jLt3jN
} ni%)a
[2Zy~`*y{
/** z)U7
* @return Returns the page. D?"P\b[/
*/ ltDohm?
public Page getPage(){ ^}p##7t[
return page; C$PS@4'U
} ^7gKs2M
<>9!oOa
/** uf#h~;B
* @return Returns the users. f%@~|:G:
*/ 8I/3T
publicList getUsers(){ i$<['DY
return users; jL^@;"/XhC
} dGBjV #bNT
G/Sp/I<d
/** 15Mtlb
* @param page pN5kcvQ
* The page to set. 7GsKD=bl]
*/ |_TI/i>?'
publicvoid setPage(Page page){ ^wd@mWxx
this.page = page; b-VygLN
} 77O$^fG2
N~8H\
/** b/:wpy+9Z
* @param users f|q/2}Bqb
* The users to set. <z,)4z++
*/ e6j1Fa9
publicvoid setUsers(List users){ u7hu8U=
this.users = users; "x=\mA#`
} ]<\YEz&A
N, Ma\D+^t
/** Uw.')ZY=
* @param userService &/WM:]^?0)
* The userService to set. mEd2f^R
*/ C(G.yd
publicvoid setUserService(UserService userService){ I!Z`'1"
this.userService = userService; F*PhV|XU
} BeVDTk:
} +zMPkbP6
KM?4J6jH
e`qrafa
Jh
E C
B&a{,.m&q6
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, gE2(E0H
}Kgi!$<aQx
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 XMI*obS'z
4<#ItQ(
么只需要: v zg^tJ
java代码: 8{G!OBxc\.
+QFKaS<sn
.pUB.l$)
<?xml version="1.0"?> NlEyT9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork f1_; da
M#'7hm6
1.0//EN" "http://www.opensymphony.com/xwork/xwork- G7 UUx+ X
A?lLK&*
1.0.dtd"> gt}Atr6>_
dA hcA.
<xwork> ; CCg]hX
Zmyq6.1q~
<package name="user" extends="webwork- @n)?=[p
lKejWT`;
interceptors"> U7x
#H~55 ))F
<!-- The default interceptor stack name *B|hRZka1A
u;q
Q/Ftb
--> W/2y;@
<default-interceptor-ref MF"*xr v
7He"IJ
name="myDefaultWebStack"/> gtuSJ+up
{A0F/#M]
<action name="listUser" %>*?uO`z[
6-wpR
class="com.adt.action.user.ListUser"> !}*vM@)1
<param u*
pQVU
|Gz<I
name="page.everyPage">10</param> LG,? ,%_s
<result U%@PY9#
%6cr4}Zm}
name="success">/user/user_list.jsp</result> K` N$nOw
</action> LOkgeJuWv
B1}i0pV,,
</package> AJ/Hw>>$?m
Ms6;iW9
</xwork> 3J"`mQ
r!!uA1!7
HHx:s2G
lD$s, hp
la{?&75]
9\!&c<i=
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 }`
3-
DL,R~
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。 X]}ai5
LkJq Bg
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Mt4]\pMUb
`S((F|Ty=;
rmw}Ui"
esSj
3E
BPkMw'a:
我写的一个用于分页的类,用了泛型了,hoho E4Q`)6]0
g=D]=&H
java代码: |E K6txRb
lJAzG,f
2f:h z
package com.intokr.util; Ds]
.Ae
yzfiH4
import java.util.List; <tTNtBb
@GAj%MK$
/** 53uptQ{
* 用于分页的类<br> aEdMZ+P.
* 可以用于传递查询的结果也可以用于传送查询的参数<br> .nIGs'P
* ,Z|O y|+'
* @version 0.01 /w dvm4
* @author cheng 0 D4 4
*/ # d"M(nt
public class Paginator<E> { ;t7F%cDA
privateint count = 0; // 总记录数 C|H`.|Q
privateint p = 1; // 页编号 tx;2C|S$oU
privateint num = 20; // 每页的记录数 ,?U(PEO\f
privateList<E> results = null; // 结果 Usht\<{
7oLl RU
/** P `<TO
* 结果总数 ST#)Fl
*/ b^[>\s'
publicint getCount(){ xz@*V>QT
return count; si%V63 ^lN
} Nc6y]eGz
uR")@Tc
publicvoid setCount(int count){ ;N!n06S3
this.count = count; ~mH'8K|l
} ZyU/ .Uk
fm^tU0DY
/** LCRWC`%&
* 本结果所在的页码,从1开始 M2:3k
* =S^ vIo)
* @return Returns the pageNo. .h
w(;
*/ f3,Xb
]h
publicint getP(){ KPK`C0mg@k
return p; %RIu'JXi
} wc6#C>=F
8/"uS ;yP
/** y}QqS/
* if(p<=0) p=1 kyB>]2
* O> wGJ.
* @param p yh4%
*/ `EP-Qlm
publicvoid setP(int p){ q<g!bW%
if(p <= 0) a<pEVV\NB~
p = 1; [eF|2:
this.p = p; 48GaZ@v
} R;/LB^X]
6>d3*
/** 78mJ3/?rC
* 每页记录数量 )]}68}9
*/ Q!fk|D+j
publicint getNum(){ wzI*QXV2s
return num; %eu_Pr 6X
} n<[H!4
G#^6H]`[J:
/** <dY{@Cgw=
* if(num<1) num=1 y3 S T"U
*/ #b=*hi`E
publicvoid setNum(int num){ 7sJGB^vM
if(num < 1) kb*b|pWlO
num = 1; F.R0c@&W
this.num = num; TsRbIq[
} DVbY
wB*}XJah
/** |F#L{=B
* 获得总页数 A `n:q;my
*/ .!hB tR
publicint getPageNum(){ ;iEFG^'tG
return(count - 1) / num + 1; {$mj9?n=v
} %@Ty,d:;=
[3QKBV1\
/** ^d2bl,1
* 获得本页的开始编号,为 (p-1)*num+1 9fL48f$
*/ .AgD`wba
publicint getStart(){ |YAnd=$
return(p - 1) * num + 1; OjiQBsgnj
} pP6pn~}
FWbA+{8
/** qrmJJSJ
* @return Returns the results. <ZM8*bqi
*/ -]h3s
>t
publicList<E> getResults(){ a~F`{(Q2
return results; n3kYVAgF
} c|'hs
]+B#SIC;
public void setResults(List<E> results){ LAwl9YnG:
this.results = results; A,T3%TE
} -l!;PV S|
v&EHp{8Qd
public String toString(){ kOGpe'bV
StringBuilder buff = new StringBuilder QxmVImn"
3' WS6B+
(); b)A$lP%`
buff.append("{"); 0r+%5}|-K
buff.append("count:").append(count); f&S,l3H<
buff.append(",p:").append(p); hD>O LoO
buff.append(",nump:").append(num); :B<lDcFKJ
buff.append(",results:").append EK^ld!g(
'%>$\Lv
(results); @])qw_
buff.append("}"); dfo{ B/+
return buff.toString(); j_?U6$xi
} (,E.1j]ji
TWC^M{e
} bYEq`kjzc
: /9@p
bQ=R,