Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 a 01s'9Be
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?r)>SB3(e
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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 6IK>v*<
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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 )L
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分页支持类: ,'YKL",
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java代码: {_4Hsw?s6
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package com.javaeye.common.util; z\,
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import java.util.List; leSBR,C
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publicclass PaginationSupport { cRag0.[
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publicfinalstaticint PAGESIZE = 30; TL"+Iv2]/$
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privateint pageSize = PAGESIZE; $@^\zg1n
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privateList items; 5xUZeLj
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privateint totalCount; aRn""3[
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privateint[] indexes = newint[0]; $Sm iN'7;
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privateint startIndex = 0; nWf8r8
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public PaginationSupport(List items, int 7r(c@4yPI
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totalCount){ })mD{c/
setPageSize(PAGESIZE); WT,dTn;W
setTotalCount(totalCount); -zt*C&)b
setItems(items); %F-yFN"
setStartIndex(0); $_HyE%F#
} &jnBDr
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public PaginationSupport(List items, int Mz)
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totalCount, int startIndex){ :zfMRg
setPageSize(PAGESIZE); \G/ZA) t
setTotalCount(totalCount); }HbUB$5
setItems(items); 8ce'G"
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setStartIndex(startIndex); HDE5Mg "
} {~\:4
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public PaginationSupport(List items, int _S &6XNV
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totalCount, int pageSize, int startIndex){ JNvgUb'U
setPageSize(pageSize); b9b`%9/L
setTotalCount(totalCount); HyQ(9cn|
setItems(items); Mg^A,8lrm
setStartIndex(startIndex); YWANBM(v+
} pNQ@aJ
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publicList getItems(){ 5Tidb$L;Du
return items; =zp{ ^mC
} "x:-#2+h
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publicvoid setItems(List items){ eq2LV=d{m
this.items = items; .o<9[d"
}
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publicint getPageSize(){ 54s90
return pageSize; ~(rZ)
} {@"
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publicvoid setPageSize(int pageSize){ C}o^p"M*B3
this.pageSize = pageSize; [[4!b E
} i MS4<`
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publicint getTotalCount(){ sv\=/F@n
return totalCount; ,>pv>)u{
} ypA 9WF
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publicvoid setTotalCount(int totalCount){ yaI jXv
if(totalCount > 0){ 85FzIX-F%
this.totalCount = totalCount; ^(qR({cX
int count = totalCount / BSEP*#s
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pageSize; pqbKPpG
if(totalCount % pageSize > 0) D/2;b;-
count++; u<+RA
indexes = newint[count]; MLDAr dvK
for(int i = 0; i < count; i++){ aMgg[g9>t
indexes = pageSize * EY :EpVin
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i; ,;=is.h9
} bh5C
}else{ y<yU5
this.totalCount = 0; AX{yfL
} Ojp|/yd^YL
} iA"H*0
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publicint[] getIndexes(){ U}-hV@y
return indexes; eoiC.$~\
} /cD]m
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publicvoid setIndexes(int[] indexes){ *+ O
this.indexes = indexes; !ZN"(0#qz
} aQ1n1OBr
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publicint getStartIndex(){ <$nMqUu0
return startIndex; z&|sks7
} ixF
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publicvoid setStartIndex(int startIndex){ 6"bdbV=t
if(totalCount <= 0) Hg[AulNna
this.startIndex = 0; ~</H>Jd
elseif(startIndex >= totalCount) <QK2Wc_}-"
this.startIndex = indexes +|O&k
? ,!C0t s
[indexes.length - 1]; YtT:\#D
elseif(startIndex < 0) 8qq'q"g
this.startIndex = 0; GYri\ <[
else{ ZV:0:k.x
this.startIndex = indexes ?uE@C3 e
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[startIndex / pageSize]; Z&y9m@
} uo^tND4a;j
} u|&a!tOf2
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publicint getNextIndex(){ F[oTc^dr
int nextIndex = getStartIndex() + 0 ^ $6U
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pageSize; }?%5Ae7l,
if(nextIndex >= totalCount) r1xhplHH@
return getStartIndex(); -;[,`g(f
else h4? 'd+K
return nextIndex; 4p/d>DTiM
} N1z:9=(I
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publicint getPreviousIndex(){ JwmH_nJ(
int previousIndex = getStartIndex() - 4kf8Am(
\&X*-T[]j
pageSize; E#+|.0*!s
if(previousIndex < 0) +C9l7 q
return0; G(7WUMjl
else Hz3KoO &
return previousIndex; J]4Uh_>)
} B3&`/{u
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} ^eWD4Vp|4
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抽象业务类 W&0KO-}ot
java代码: !5[5l!{x
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/** 6
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* Created on 2005-7-12 $"x~p1P
*/ =!|=Y@
package com.javaeye.common.business; '"Y(2grP
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import java.io.Serializable; i@#fyU)[G
import java.util.List; $"]*,=-X
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import org.hibernate.Criteria; "\M^jO
import org.hibernate.HibernateException; S-KHot ?
import org.hibernate.Session; >-Q=o,cl%3
import org.hibernate.criterion.DetachedCriteria; A"~4|`W
import org.hibernate.criterion.Projections; {Zy)p%j8
import IH~[/qNk
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org.springframework.orm.hibernate3.HibernateCallback;
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import <;nhb
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org.springframework.orm.hibernate3.support.HibernateDaoS YhNO{4D
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upport; GbN|!,X1m
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import com.javaeye.common.util.PaginationSupport; xnD"LK
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public abstract class AbstractManager extends M[7$cfp-Y~
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HibernateDaoSupport { ORP-@-dap
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privateboolean cacheQueries = false; P+t`Rw
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privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean K/ 5U;oC
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cacheQueries){ ct![eWsuB
this.cacheQueries = cacheQueries; ~zT7 43
} N.@@ebuE
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publicvoid setQueryCacheRegion(String I&G"{Dl94
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queryCacheRegion){ mJ L=H
this.queryCacheRegion = |QB[f*y5
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queryCacheRegion; >crFIkOJ
} _/`H<@B_U
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publicvoid save(finalObject entity){ 0JM`*f%n
getHibernateTemplate().save(entity); H$={i$*,Y
} M"Q{lR
];8S<KiS~
publicvoid persist(finalObject entity){ #9ZHt5T=$
getHibernateTemplate().save(entity); =/SBZLR(9
} !{%BfZX<&
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publicvoid update(finalObject entity){ >s|zrS)
getHibernateTemplate().update(entity); X/' t1
} w=feXA3-S
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publicvoid delete(finalObject entity){ {kNV|E
getHibernateTemplate().delete(entity); N(=Z4Nk5
} RJk4 2;]
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publicObject load(finalClass entity, ^ ^T e
@K=C`N_22
finalSerializable id){ >JckN4v
return getHibernateTemplate().load {~cM 6W]f
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(entity, id); NY3.?@Z
} "1HKD
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publicObject get(finalClass entity, r:-,qy
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finalSerializable id){ Hx#1TqC/
return getHibernateTemplate().get yHYK,3/C,
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(entity, id);
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} BOdd~f%&tn
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publicList findAll(finalClass entity){ {DWL 5V#M
return getHibernateTemplate().find("from [Lal_}m?
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" + entity.getName()); iV2v<ap.n
} !\Vc#dslt
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publicList findByNamedQuery(finalString g?E8zf `
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namedQuery){ 7*\CfqrU
return getHibernateTemplate 3}kG ]#
q@[UeXu?pZ
().findByNamedQuery(namedQuery); _2
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} s&7TARd
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publicList findByNamedQuery(finalString query, ( we)0AxF'
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finalObject parameter){ 0"J0JcFX
return getHibernateTemplate t5RV-$
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().findByNamedQuery(query, parameter); qN\?cW'
}
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publicList findByNamedQuery(finalString query, 9oQ$w?=#$
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finalObject[] parameters){ )0?u_Z]w9
return getHibernateTemplate -]<<}@NF
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().findByNamedQuery(query, parameters); %Hu?syo
} AjD?_DPc
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publicList find(finalString query){ 4@r76v}{
return getHibernateTemplate().find G3dA`3
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(query); )m_q2xV
} |'qvq/#^
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publicList find(finalString query, finalObject ~CuJ$(9Y
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parameter){ Te2C<c
return getHibernateTemplate().find (tvfF0~
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(query, parameter); N$N7aE$
} %E2V$l0
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public PaginationSupport findPageByCriteria ;
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(final DetachedCriteria detachedCriteria){ {PKf]m
return findPageByCriteria rT_J6F5J
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); EGVS8YP>h
} LK+67Y{25
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public PaginationSupport findPageByCriteria IoZ_zz0
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(final DetachedCriteria detachedCriteria, finalint DT3"uJTt
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startIndex){ >|aVGY
return findPageByCriteria KAg-M#
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(detachedCriteria, PaginationSupport.PAGESIZE, 5Nl?Km~
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startIndex); K-[;w$np0
} GT,1t=|&V
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public PaginationSupport findPageByCriteria A|YiSwyy
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(final DetachedCriteria detachedCriteria, finalint XhUVDmeUMb
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pageSize, rvuasr~
finalint startIndex){ G=er0(7<
return(PaginationSupport) RFPcH8-u7
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getHibernateTemplate().execute(new HibernateCallback(){ fJ=v?
publicObject doInHibernate QXW>}GdKZ
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(Session session)throws HibernateException { >XxHp
Criteria criteria = @r=,:
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detachedCriteria.getExecutableCriteria(session); -S#jOr
int totalCount = 3_8W5J3I
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((Integer) criteria.setProjection(Projections.rowCount .bUj
3&6sQ-}*
()).uniqueResult()).intValue(); VTwQD"oB
criteria.setProjection 6^lix9q7
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(null); "RTv[n!
List items = .F N
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criteria.setFirstResult(startIndex).setMaxResults b=5ZfhIg[
~n$\[rQ
(pageSize).list(); Ehxu`>@N
PaginationSupport ps = Hb/8X
!=
nk;^sq4M:
new PaginationSupport(items, totalCount, pageSize, a$\Bt_
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startIndex); nok-![
return ps; "'C5B>qO
} 9h/Hy aN
}, true); sX-@
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} c
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public List findAllByCriteria(final Ww"]3
qeb} ~FL"o
DetachedCriteria detachedCriteria){ C-\3,
return(List) getHibernateTemplate %|j8#09
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().execute(new HibernateCallback(){ p[&b@U#
publicObject doInHibernate a?xZsR
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(Session session)throws HibernateException { M2\c0^R
Criteria criteria = I E{:{b\
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detachedCriteria.getExecutableCriteria(session); Wt=\hixj-
return criteria.list(); |AT`(71
} ;/t~MH
}, true); %w?C)$Kn\
} WZTAXOw
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public int getCountByCriteria(final J~n|5*cz
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DetachedCriteria detachedCriteria){ fjy7 gC2
Integer count = (Integer) [jksOC)@4
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getHibernateTemplate().execute(new HibernateCallback(){ TY%=Y=
publicObject doInHibernate B3pjli
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(Session session)throws HibernateException { !K0 U..
Criteria criteria = i]OEhB
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detachedCriteria.getExecutableCriteria(session);
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return ns*:mGh
#SG.`J<%
criteria.setProjection(Projections.rowCount dS\!tdHP-Q
-2(?O`tZ
()).uniqueResult(); X%iJPJLza
} R1/c@HQw?
}, true); JPHM+3v
return count.intValue(); evpy%/D
} <LzxnTx=
} V%z?wDC
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用户在web层构造查询条件detachedCriteria,和可选的 $VB
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 q]?)c
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PaginationSupport的实例ps。 K&zW+C b
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ps.getItems()得到已分页好的结果集 KVr9kcs
ps.getIndexes()得到分页索引的数组 Gz BPI'C
ps.getTotalCount()得到总结果数 ,k=8|=aF
ps.getStartIndex()当前分页索引 ~#i2reG5
ps.getNextIndex()下一页索引 !tcz_%
ps.getPreviousIndex()上一页索引 ,RM8D)m\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;]b4O4C\
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Z4c'1-lh
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一下代码重构了。 y:^o._
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我把原本我的做法也提供出来供大家讨论吧: j"hEs(t
S3i p?9
首先,为了实现分页查询,我封装了一个Page类: #oFyi @U
java代码: YM6
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/*Created on 2005-4-14*/ }mzd23^W>P
package org.flyware.util.page; idGn{f((f
s^SU6P/]
/** "(vK.-T
* @author Joa ^1vKhO+p$
* UP$>,05z6
*/ L6DYunh}^N
publicclass Page { rfYa<M Qc
lS#:u-k
/** imply if the page has previous page */ &M@c50&%
privateboolean hasPrePage; (_8.gS[
#z
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P"
/** imply if the page has next page */ %8h=_(X\7
privateboolean hasNextPage; <7SE|
I.G[|[. Do
/** the number of every page */ HA,8O[jon
privateint everyPage; RgUQ:
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/** the total page number */ eY'nS
privateint totalPage; 4L ]4WVc
`GW&*[.7
/** the number of current page */ |59)6/i
privateint currentPage; c*.
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/** the begin index of the records by the current F8dr-"G
8>W52~^fU
query */ leb/D>y
privateint beginIndex; !=PH5jTY
@TD=or .&
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/** The default constructor */ s~2o<#
public Page(){ 7<*0fy5n n
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} VFx[{Hy
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/** construct the page by everyPage WeaT42*Q{
* @param everyPage `4snTM!v&
* */ ]u!s-=3s
public Page(int everyPage){ )B"{B1(
this.everyPage = everyPage; cu
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} |9\i+)C
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/** The whole constructor */ >r7PK45.K
public Page(boolean hasPrePage, boolean hasNextPage, J$42*S Y
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%K')_NS@
int everyPage, int totalPage, LKp;sV
int currentPage, int beginIndex){ V^R,j1*
this.hasPrePage = hasPrePage; fdX|t"oz
this.hasNextPage = hasNextPage; d^nO&it
this.everyPage = everyPage; !reOYt|
this.totalPage = totalPage;
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this.currentPage = currentPage; iKV|~7nwO
this.beginIndex = beginIndex; "{qnm+G
} L(K 5f7\
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/** MGMJeqvr
* @return ]r3/hDRDL@
* Returns the beginIndex. YW6a?f^!
*/ %a
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publicint getBeginIndex(){ 4-SU\_
return beginIndex; *cCx]C.~
} 4gC(zJ
b way+lh
/** X>yDj]*4P
* @param beginIndex ZCj1Cz]"l<
* The beginIndex to set. ><D2of|
*/ iTq&h=(n
publicvoid setBeginIndex(int beginIndex){ 0C%IdV%CU
this.beginIndex = beginIndex; Z81;Y=(
} #J3o~,t<
B
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/** }(!Uq
* @return =|aZNHqH
* Returns the currentPage. gAorb\iJ
*/ G!sfp}qW
publicint getCurrentPage(){ C.:S@{sK
return currentPage; hvO$ f.i
} G4:\6fu
Be@g|'r
/** rZpsC}C'
* @param currentPage }=R0AKz!Cv
* The currentPage to set. ;f[##=tm
*/ ?2da6v,t
publicvoid setCurrentPage(int currentPage){ 9q$^x/z!
this.currentPage = currentPage; Xwo+iZ(a
} 8CRbo24"s
O&aD]~|
/** //|B?4kk
* @return \
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* Returns the everyPage. r2+ZxMo|
*/ ysK J=
publicint getEveryPage(){ ?+7~E8
return everyPage; H
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} F*#!hWtb
\8<[P(!3
/** C^,baCX
* @param everyPage lJ= EP.T
* The everyPage to set. Io JI|lP
*/ *bYU=RS
publicvoid setEveryPage(int everyPage){ 8g)$%Fy+N
this.everyPage = everyPage; ^_\m@
} ]!sCWR
v\8v' EDP
/** |-{e!&
* @return ktynIN
* Returns the hasNextPage. (n.IK/:
*/ oKGF'y?A>
publicboolean getHasNextPage(){ 3=oxT6"k
return hasNextPage; cSB_b.@"1
} H'udxPF
>f Hu
/** --"5yGOL
* @param hasNextPage P3W3+pwq
* The hasNextPage to set. _u6NaB
*/ q:M'|5P
publicvoid setHasNextPage(boolean hasNextPage){ b49h @G
this.hasNextPage = hasNextPage; $Bc3| `K1v
} `u_MdB}<x;
#W/Ch"Kv
/** Lz_.m
* @return 4@\$k+v
* Returns the hasPrePage. PE6,9i0ee
*/ _i7yyt;h
publicboolean getHasPrePage(){ EX!`Zejf
return hasPrePage; |ITCw$T
} K@2"n|
S;
:%AEwRZ
/** t+F_/_"B
* @param hasPrePage .
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* The hasPrePage to set. NQuqM`LSQ
*/ ct=K.m@E%X
publicvoid setHasPrePage(boolean hasPrePage){ |BhL.
this.hasPrePage = hasPrePage; x|d? '
} YW~ 9 N
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/** 98
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* @return Returns the totalPage. ep},~tPZn
* ^+d]'$
*/ B>cT<B
publicint getTotalPage(){ lcEK&AtK
return totalPage; #/H2p`5
} =(\BM')l
x)eF{%QB
/** YZ:C9:S6X
* @param totalPage 9* 3;v;F
* The totalPage to set. {0a\<l
*/ HrZX~JnTmf
publicvoid setTotalPage(int totalPage){ 8BZ&-j{
this.totalPage = totalPage; n!SHExBp
} \5j}6Wj
sz/^Ie-~
} P'}B5I~
m:0[as=
{fV$\^c
=6 zK1Z
(dyY@={q
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 [lSQMoi3
2v@B7r4}
个PageUtil,负责对Page对象进行构造: 2)0J@r'
java代码: tEo-Mj5:
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/*Created on 2005-4-14*/ nnT#S
package org.flyware.util.page; YIgHLM(
o-l-Z|)7
import org.apache.commons.logging.Log; Bvj sl
import org.apache.commons.logging.LogFactory; (@!K tW
:06.b:_
/** HIE8@Rv/3
* @author Joa zAklS 7L
* ?D)$OCS
*/ L$);50E
publicclass PageUtil { eYlI };
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UP
privatestaticfinal Log logger = LogFactory.getLog ;&}z
L.!jo
!j%
(PageUtil.class); ?ILjt? X8
O(=9&PRi
/** 2T(+VeMQ=
* Use the origin page to create a new page &&LB0vH!J
* @param page MXEI/mDYK
* @param totalRecords {29aNm
* @return Rcw[`q3/
*/ ?Y8hy|`
publicstatic Page createPage(Page page, int Q_iN/F
x6!Q''f7
totalRecords){ }
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return createPage(page.getEveryPage(), cjg~?R
ErJ@$&7
page.getCurrentPage(), totalRecords); 0 } &/n>F
} QT%vrXzz
puWMgvv
/** k%O3\q
* the basic page utils not including exception ^^B_z|;Aa
\.H9e/vU`
handler fXl2i]L(^B
* @param everyPage ZbdGI@
* @param currentPage SRk!HuXh
* @param totalRecords @>~\So|
* @return page L'aB/5_%
*/ sb8bCEm-\
publicstatic Page createPage(int everyPage, int .{`C>/"}
r[;d.3jtP
currentPage, int totalRecords){ r`EjD}2d
everyPage = getEveryPage(everyPage); g:y4C6b
currentPage = getCurrentPage(currentPage); 6\K\d_x
int beginIndex = getBeginIndex(everyPage, {}Is&^3Z
q<z8P;oP^
currentPage); U2W Hs3
int totalPage = getTotalPage(everyPage, <1>6!`b4
R@tEC)Zn
totalRecords); M
| "'`zc
boolean hasNextPage = hasNextPage(currentPage, NqOX);'L0
m&xVlS
totalPage); u
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N|.3
boolean hasPrePage = hasPrePage(currentPage); v;;3 K*c>
g<0K
i^#
returnnew Page(hasPrePage, hasNextPage, )mBYW}} T
everyPage, totalPage, vS0 ii
currentPage, Ma$~B0!;s
Z^as ?k(iM
beginIndex); \
ya@9OA
} 5.&)hmpg
KZZ Y9
privatestaticint getEveryPage(int everyPage){ Jkbeh.
return everyPage == 0 ? 10 : everyPage; e_KfnPY
} ?H@<8Ra=3
gSw<C+
privatestaticint getCurrentPage(int currentPage){ '#LzQ6Pn
return currentPage == 0 ? 1 : currentPage; h{ix$Xn~
} Y.Z:H!P);$
YOGj__:
privatestaticint getBeginIndex(int everyPage, int 'xkl|P>=],
S-gO
currentPage){ BYM6cp+S
return(currentPage - 1) * everyPage; P3|s}&
} a <?~1pWtc
Bh cp=#
privatestaticint getTotalPage(int everyPage, int 76<mP*5
,z/aT6M?H
totalRecords){ y<Xu65
int totalPage = 0; {b4`\I@<
#*_!Xc9f
if(totalRecords % everyPage == 0) -q{N1?tcy
totalPage = totalRecords / everyPage; lbIPtu
else o#f"wQH;p
totalPage = totalRecords / everyPage + 1 ; ws!~MSIy
O=}Rp1
return totalPage; j+ -r(lZ
} b- t
eU%49 A
privatestaticboolean hasPrePage(int currentPage){ b=:u d[h
return currentPage == 1 ? false : true; -#;xfJE
} ~,1Sw7rE
={oNY.(Q
privatestaticboolean hasNextPage(int currentPage, J$1H3#VVG
;]=w6'dP!
int totalPage){ T
pF[-fO
return currentPage == totalPage || totalPage == a6DR' BC
xLoQ0rt
6
0 ? false : true; X7L:cVBg
} `<se&IZE
KU` *LB:
T&]-p:mg^
} lNg){3
6 V0Ayxg7
JJ?rVq1g
IV. })8
#c@&mus
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 4y7_P0}:B
-]zb3P
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \N0vA~N.
t
sUu
做法如下: <nbklo
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 EyPJ Jc8
NC-K`)
的信息,和一个结果集List: _`\!+qGq
java代码: YWH>tt9
\M\7k5$
klm>/MXI`
/*Created on 2005-6-13*/ >bZ-mX)j\0
package com.adt.bo; Ei @
L@(. i
import java.util.List; nI6ompTX
!mUJ["#
import org.flyware.util.page.Page; [h;I)ug[o(
\~%+)a%%
/** wX]$xZ!s
* @author Joa Pa3-0dUr
*/ !9/`PcNIpy
publicclass Result { QNMZR
:\"0jQ.y|
private Page page; raPOF6-_rH
a&8K5Z%0
private List content; >tcEx(
;Y*K!iFWH
/** IXa~,a H71
* The default constructor *2a" 2o
*/ l6HtZ(
public Result(){ K)LoZ^x0)
super(); mv8H:T
} =exCpW>
e*}zl>f
/** 'D5J5+.z
* The constructor using fields St%x\[D
* "crR{OjE"
* @param page T/P\j0hR
* @param content q\o#<'F1J
*/ AEyD?^?
public Result(Page page, List content){ (rBsh6@)
this.page = page; Zio!j%G
this.content = content; #2_FM!e
} GE!nf6>Km
*%;A85V/
/** "t4z)j;
* @return Returns the content. Cst1nGPL
*/ ~&)\8@2
publicList getContent(){ Opu*i
return content; M,H8ZO:R
} Ljz)%y[s
2T2<I/")O
/** G^)]FwTs
* @return Returns the page. a^J(TW/
*/ ]C,j80+pK
public Page getPage(){ #0<pRDXj
return page; 2PSExK57
} j
"<?9/r
8m
iJQIq
/** ^;PjO|mD
Z
* @param content f<bB= 9J
* The content to set. M{24MF
*/ g.9C>>tj
public void setContent(List content){ _$>);qIP4
this.content = content; aF?_V!#cT
} I20~bW
1M??@@X
/** G)<B7-72;
* @param page c.]QIIdK
* The page to set. 0<`qz |_h
*/ G^d3$7
publicvoid setPage(Page page){ /P,1KVQPh
this.page = page; I*a@_EO
} #(614-r/
} ?fy37m(M}
/Kli C\
QHO n?e
cN&Ebn
G>vK$W$f N
2. 编写业务逻辑接口,并实现它(UserManager, *$0*5d7
8X`DFeJ
UserManagerImpl) 3 twA5)v
java代码: zS;ruK%2
k)>H=?mI
Ql5bjlQdO
/*Created on 2005-7-15*/ n+=qT$w)
package com.adt.service; $;Fx Zkp
Xf&YcHo
import net.sf.hibernate.HibernateException; X:Z3R0
p)B/(%
import org.flyware.util.page.Page; ^oPFLez56
_=I1
import com.adt.bo.Result; 'hr_g* i
M%ecWr!tj
/** x*z[(0g!
* @author Joa Jt]RU+TB
*/ Q|o$^D,
publicinterface UserManager { [&99#7B
V6dq8Z"h
public Result listUser(Page page)throws Fj<*!J$,
l3b=8yn.
HibernateException; 'm*W<
QTa\&v[f
} B;[ .u>f
ldTXW(^j
_0Ea 3K
?=Ceo#Er
-b!Z(}JK
java代码: ^)]U5+g?
yrEh5v:
K.QSt
/*Created on 2005-7-15*/ zl8M<z1`1
package com.adt.service.impl; i=<;$+tW
5?H8?~&dz
import java.util.List; z#&1>
9cB+x`+Lu
import net.sf.hibernate.HibernateException; 9oc_*V0<
If'2
m_
import org.flyware.util.page.Page; L3\#ufytb
import org.flyware.util.page.PageUtil; ZbT$f^o}M]
8zeeC
eI U
import com.adt.bo.Result; >6Uc|D
import com.adt.dao.UserDAO; L,A+"
import com.adt.exception.ObjectNotFoundException; -'qVnu
import com.adt.service.UserManager; tUH?N/qn
T=YVG@fm?
/** '9u?lA^9$
* @author Joa jA9uB.I,"b
*/ h9 DUS,G9,
publicclass UserManagerImpl implements UserManager { {K+f&75
%]7 6u7b/
private UserDAO userDAO; K!\v?WbF
FW8Zpr!u
/** AjEy@/
* @param userDAO The userDAO to set. =_BHpgL
*/ Y)/|C7~W
publicvoid setUserDAO(UserDAO userDAO){ %bTuE' `b
this.userDAO = userDAO; X7-*`NI^
} A"pQOtrm\k
_Vp"G)1Y
/* (non-Javadoc) b}NNkM
* @see com.adt.service.UserManager#listUser NUVKAAgMX
$)NS]wJ]3
(org.flyware.util.page.Page) ,*W~M&n"m
*/ ,&@GxiU
public Result listUser(Page page)throws ?l%4
P5
4F.,Y3
HibernateException, ObjectNotFoundException { P`@Rt
int totalRecords = userDAO.getUserCount(); C[%Qg=<
if(totalRecords == 0) 55s5(]`d
throw new ObjectNotFoundException P]n0L4c
BNJ0D
("userNotExist");
Z:^#9D{
page = PageUtil.createPage(page, totalRecords); M>5OC)E
List users = userDAO.getUserByPage(page); + Fo^NT
returnnew Result(page, users); gk| %
4.
} !`N:.+DT
pnSKIn
} ZMlBd}H
OR6vA5J
Lqxhy s
vrb@::sy0T
v\|jkzR5Y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 `w#VYs|k
nxV!mh_
询,接下来编写UserDAO的代码: v\dQjQu8m
3. UserDAO 和 UserDAOImpl: Tk[]l7R~
java代码: (bv{17K
:@jctH~
QWa@?BO2p
/*Created on 2005-7-15*/ W8bp3JX"
package com.adt.dao; F8<G9#%s\
ByP<-Deh
import java.util.List; !0hyp |F:>
Gn4b*Y&M]3
import org.flyware.util.page.Page; (N&i4O-I
py7Zh%k
import net.sf.hibernate.HibernateException; w( SY
A^M]vk%dg
/** tnUfi8\ob
* @author Joa wbF`wi?
*/ er24}G8
publicinterface UserDAO extends BaseDAO { gmH`XKi\
|Q)mBvvN
publicList getUserByName(String name)throws @"NP`#
xltN-<n7
HibernateException; ^_3Ey
v`QDms,{
publicint getUserCount()throws HibernateException; ?XdvZf $
QAx9W%
publicList getUserByPage(Page page)throws xP~GpVhLF
ds+K7B$
HibernateException; \(
V1-,
I,#E`)
} Q e+;BE-H
m%u`#67oK
f_O|
I~F&@
l (rm0_
java代码: i/-IjgM"-
Epp>L.?r
.S|T{DMQ[
/*Created on 2005-7-15*/ j;uUM6
package com.adt.dao.impl; FVl,
ttW
p@~Y[a =
import java.util.List; 7.VP7;jys
]tu
OWR
import org.flyware.util.page.Page; M887 Q'HSi
^A&{g.0
import net.sf.hibernate.HibernateException; (*r2bm2FPO
import net.sf.hibernate.Query; ]T/%Bau
+|bmUm<2
import com.adt.dao.UserDAO; `^{G`es
5'f_~>1Wt
/** H0inU+Ih
* @author Joa PTe$dPB
*/ 5P<1I7d
public class UserDAOImpl extends BaseDAOHibernateImpl 0vLx={i
[sG`D-\P[
implements UserDAO { gYN;Fu-9Z
XGR63hXND
/* (non-Javadoc) KB~1]cYMp
* @see com.adt.dao.UserDAO#getUserByName
,d/$!Yf
2|\mBP`ok
(java.lang.String) I`XOvSO
*/ -"ZNkC=
publicList getUserByName(String name)throws !{V`N|0
cHr]{@7Cs
HibernateException { YIW9z{rrs
String querySentence = "FROM user in class X sJ`x
d(t)8k$
com.adt.po.User WHERE user.name=:name"; }N-UlL(
Query query = getSession().createQuery XelFGT E
W20- oZ8
(querySentence); XOqHzft h6
query.setParameter("name", name); 9nQyPb6
return query.list(); ApSseBhh
} P\WHM(
>DY/CcG\P
/* (non-Javadoc) Z(RsB_u5
* @see com.adt.dao.UserDAO#getUserCount() v,ecNuy*d
*/ @>U9CL"
publicint getUserCount()throws HibernateException { wH@<0lw`<
int count = 0; OO/>}? ob
String querySentence = "SELECT count(*) FROM zx"EAF{
Bi fI.2|
user in class com.adt.po.User"; 8bMw.u=F
Query query = getSession().createQuery m8L %!6o
\4$Nx/@Q}
(querySentence); ?~.9:93
count = ((Integer)query.iterate().next n5xG4.#G
anz7ae&P'K
()).intValue(); `::j\3B&Y-
return count; Us "G X_
} o(v`
Z{(Gib~{N
/* (non-Javadoc) !^L}LtqHI
* @see com.adt.dao.UserDAO#getUserByPage nUONI+6Z/
S|u5RU8*"|
(org.flyware.util.page.Page) mhIGunK;+
*/ zB y%$5~Fw
publicList getUserByPage(Page page)throws u]B
b ^[
<F_w4!
HibernateException { r{yIF~k@
String querySentence = "FROM user in class "o;%em*Bc
,agkV)H
com.adt.po.User"; Jt8M;Yk
Query query = getSession().createQuery eWYet2!Q
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(querySentence); .-s!} P"
query.setFirstResult(page.getBeginIndex()) Qh3+4nLFtb
.setMaxResults(page.getEveryPage()); i-0AcN./p
return query.list(); T06w`'aL
} <5]_u:
4mBM5Tv
} bU}!bol
jj `0w@
T2W^4)
-=rGN"(M
_
/s)It
至此,一个完整的分页程序完成。前台的只需要调用 %E,-dw
79Q,XRWh|
userManager.listUser(page)即可得到一个Page对象和结果集对象 3s:)CXO
<C"}OW8
的综合体,而传入的参数page对象则可以由前台传入,如果用 3 5-FD{
ioTqT:.
webwork,甚至可以直接在配置文件中指定。 *qMjoP,
~c1~)QzZ
下面给出一个webwork调用示例: AsZyPybq
java代码: \<%FZT_4~
#lVSQZO~a
:]C\DUBo
/*Created on 2005-6-17*/ [MC}zd'/
package com.adt.action.user; U_B`SS
A^c5CJ_
import java.util.List; ; zy;M5l5.
nzYFa J +
import org.apache.commons.logging.Log; jaux:fU
import org.apache.commons.logging.LogFactory; dnPr2oI?I
import org.flyware.util.page.Page; 4f0dc\$
GEb)nHQq
import com.adt.bo.Result; |("5 :m
import com.adt.service.UserService; hW cM.
import com.opensymphony.xwork.Action; Ke&fTK
nDchLVw
/** t^9q>[/d`
* @author Joa H~*[v"
*/ &P8Q|A-u
publicclass ListUser implementsAction{ x2f_>tu2
FUPJ&7+B
privatestaticfinal Log logger = LogFactory.getLog Ug O \+cI
>yqL
(ListUser.class); oWOH #w
z#&qWO
private UserService userService; ~u-`L+G"6
tQ?}x#J
private Page page; |@)ij c4i
bL7mlh
privateList users; !C0=
h
b}q,cm
/* ]zK} X!
* (non-Javadoc) s*}d`"YvH
* 0$49X
* @see com.opensymphony.xwork.Action#execute() b}G +7B
*/ ]7"mt2Q=3
publicString execute()throwsException{ Vk~}^;`Y
Result result = userService.listUser(page); G}~b
page = result.getPage(); d{GXFT;0
users = result.getContent(); WI'csM;M#
return SUCCESS; ln!KL'T]
} }mJ)gK5b 6
B "}GAk}V
/** I`KN8ll
* @return Returns the page. ')FNudsC
*/ PwNLJj+%
public Page getPage(){ q+G1#5
return page; Kd,m;S\
} XJOo.Y
anV)$PT=
/** aA
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* @return Returns the users. 'Ph;:EMj
*/ )I}G:bBa
publicList getUsers(){ If#7SF)n'
return users; 1X9sx&5H
} CC87<>V
nocH~bAf2
/** !kKKJ~,;
* @param page \1B*iW
* The page to set. wYawG$@_
*/ p9sxA|O=y
publicvoid setPage(Page page){ 4-n.4j|
this.page = page; bKaV]Uy
} SO&;]YO
9_/1TjrDN
/** U&a]gkr
* @param users ^e 6(#SqR
* The users to set. %E!0,y,:
*/ fu&]t8MJC
publicvoid setUsers(List users){ G`W+m*[U+M
this.users = users; BzUx@,
} hP#&]W3:
\%^3Izsc
/** gR>#LM&dG
* @param userService M*{e e0\`r
* The userService to set. C]XDDr
*/ ~gDtj&F
publicvoid setUserService(UserService userService){ ozo8 Tr
this.userService = userService; liB>~DVC
} _0`O}
} 5m3sjcp_
t2$:*PvE
gy[uqm_ T
\
a<Ye
T
1wM
p3
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, 1|89-Ii]
5~?
J
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 abv]
TP^0`L
么只需要: \dMsv1\
java代码: [)=FZF6kG
']NM_0
$_UF9l0
<?xml version="1.0"?> Q&LkST-i
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork EkBM>*W
mnia>;
0H
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,5*4%*n\
j?(QieBH
1.0.dtd"> fe$WR~
(TQXG^n$gY
<xwork> 'mM5l*{
RinRQd
<package name="user" extends="webwork- btE+.V
/ u{r5`4
interceptors"> M>#{~zr
v]!7=>/2
<!-- The default interceptor stack name J5"*OH:f
*$1)&2i
--> *%e#)sn*
<default-interceptor-ref -d~'tti
5*r6#[S\
name="myDefaultWebStack"/> (
FRf.mv{
Sm,$~~iq}
<action name="listUser" 9+']`=a:
=EJ"edw]%0
class="com.adt.action.user.ListUser"> VGq]id{*$
<param |"<
I\Vs:
gr=`_k4~1
name="page.everyPage">10</param> sFTIRVXN,
<result -iHhpD9"X
bW]+Og
name="success">/user/user_list.jsp</result> F8I<4S
</action> 2 *$n?
\zUsHK?L"t
</package> mI%/k7:sf
$\
'\@3o
</xwork> ^xwFjQXx
| |=Duk
1^3#3duV
>e ;f{
rWXW}Yg
jlBCu(.,_
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 fLAF/#\2
*@nUas2"
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 d#Ajb
-wfV
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 [Bo$?
ise}> A!t
&?6w2[}
mtHz6+
v_0!uT5~NE
我写的一个用于分页的类,用了泛型了,hoho \irjIXtV
dk/*%a
+
java代码: N}G(pq}
1`{ib
G65N:
package com.intokr.util; D$E9%'ir
(xed(uFEK
import java.util.List; +.I'U9QeUN
P;&p[[7
/** N~jQ!y
* 用于分页的类<br> 5nAF =Bj
* 可以用于传递查询的结果也可以用于传送查询的参数<br> [)~@NN
* )g_zPt
* @version 0.01 UAZ&*{MM^
* @author cheng hJsC
\ C,^
*/ 4
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public class Paginator<E> { Yur)_m
privateint count = 0; // 总记录数 ;r"B?] JO
privateint p = 1; // 页编号 em}Qv3*#
privateint num = 20; // 每页的记录数 1 ,'^BgI,
privateList<E> results = null; // 结果 -d'|X`^nE
GNc|)$
/** ,0]28D
* 结果总数 nn4Sy,cz
*/ I;H9<o5
publicint getCount(){ wf%Ep#^6}
return count; A>A'dQ69
} >r3< O=Z7
5Suc#0y
publicvoid setCount(int count){ ?
M_SNv
this.count = count; ZS]f+}0/}
} `r(J6,O
\r,.hUp
/** lG>e6[Wc
* 本结果所在的页码,从1开始 Y26l,XIV
*
}92lr87
* @return Returns the pageNo. !p2,|6Y`y
*/ 1iL
xXd
publicint getP(){
hP8&n9o
return p; $4JX#lkt
} }tO<_f))
Lu.tRZ`$38
/** '<S:|$$
* if(p<=0) p=1 ItE~MJ5p
* a' o8n6i
* @param p }p?V5Qp
*/ Vj`s_IPY
publicvoid setP(int p){ PJ:5Lb<
if(p <= 0) $ywh%OEH
p = 1; +N:6wZ7<f
this.p = p; }A/&]1GWk
} 6F/
OlK<
jYID44$
/** eAKQR
* 每页记录数量 !&p:=}s
*/ U]
-@yx
publicint getNum(){ f?zK"
return num; ]Wt6V^M'@
} M`pTT5r
oHd0
<TO
/** +gCy@_2;
* if(num<1) num=1 P Xn>x8z
*/ 1'm`SRX#e
publicvoid setNum(int num){ LE80`t>M#
if(num < 1) *1S.9L
num = 1; *Ne2l`!1m
this.num = num; xh^ZI6L<
} /M*\t.[ 46
8;f<q u|w
/** PG[O?l
* 获得总页数 7C7(bg,7^
*/ / !
publicint getPageNum(){ 0*/ r'
return(count - 1) / num + 1; !_H8Q}a
} |SukiXJZF
<;0N@
/** ';|>`<
* 获得本页的开始编号,为 (p-1)*num+1 {^5<{j3e
*/ c0Ro3j\p
publicint getStart(){ as|c`4r\O
return(p - 1) * num + 1; ;6
6_G Sjz
} `m; "I
^npS==Y]!.
/** 9iddanQA
* @return Returns the results. +\[![r^P
*/ `e'o~oSu
publicList<E> getResults(){ .O%1)p
return results; CSqb)\8Oi*
} ]op^dW1;0_
bo !]
public void setResults(List<E> results){ ~eOj:H
this.results = results; {e[pSD6
} AH87UkNL
= *;Xc-_
public String toString(){ w$[Ds
StringBuilder buff = new StringBuilder Q1I_=fT
*5_8\7d
(); y_4krY|Zx
buff.append("{"); #JR ,C
-w
buff.append("count:").append(count); 9eN2)a/
buff.append(",p:").append(p); VO;UV$$
buff.append(",nump:").append(num); | ]!Ky[P
buff.append(",results:").append B6'%J
&Bz7fKCo
(results); V_A,d8=lt
buff.append("}"); 6|>\&Y!Q
return buff.toString(); NuS|X
} {}J@+Zsi
(06Vcqg
} ;ko[(eFN@
A;WwS?fyQ
/mBBeg^a