Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1,;qXMhK`;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 WKYA9BaR
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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 31o7R &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 9>$%F;JP44
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分页支持类: L[[H\
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java代码: IpaJ<~ p
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package com.javaeye.common.util; y
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import java.util.List; I!0 $%
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publicclass PaginationSupport { EJ
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publicfinalstaticint PAGESIZE = 30; x+)hL
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privateint pageSize = PAGESIZE; yn ?U7`V
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privateList items; J\,e/{,X
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privateint totalCount; 5-QvQ&eH.
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privateint[] indexes = newint[0]; C>K"ZJ
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privateint startIndex = 0; Z5^,!6
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public PaginationSupport(List items, int bM3'm$34
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totalCount){ MT#[ -M\
setPageSize(PAGESIZE); 8KdcLN@
setTotalCount(totalCount); =B{$U~}
setItems(items); DrCfC[A~]
setStartIndex(0); },QFyT
} iNrmhiql
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public PaginationSupport(List items, int ewff(e9
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totalCount, int startIndex){ K
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setPageSize(PAGESIZE); WZO
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setTotalCount(totalCount); O [ ; 6E
setItems(items); []fj~hj
setStartIndex(startIndex); W!9f'Yn
} r@V(w`
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public PaginationSupport(List items, int 1p5q}">z
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totalCount, int pageSize, int startIndex){ [.#$hOsNR
setPageSize(pageSize); 'w$we6f
setTotalCount(totalCount); apWrcaj
setItems(items); 1nM?>j%k
setStartIndex(startIndex); j~j
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} 1~ZHC[ `
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publicList getItems(){ %$-3fj7
return items; HvfTC<+H
} f*H}eu3/j
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publicvoid setItems(List items){ nv|y@!(
this.items = items; 6nk|*HPz
} JC?V].) y5
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publicint getPageSize(){ g8@i_
return pageSize; [zt&8g
} )UU6\2^
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publicvoid setPageSize(int pageSize){ KB-#):'
this.pageSize = pageSize; HQ#L
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} gRd1(S
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publicint getTotalCount(){ |P?B AWYeQ
return totalCount; -`<N,
} X/D9%[{&
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publicvoid setTotalCount(int totalCount){ p.7p,CyB
if(totalCount > 0){
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this.totalCount = totalCount;
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int count = totalCount / ON=ley
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pageSize; *} 4;1OVT
if(totalCount % pageSize > 0) ]tV{#iIJ*
count++; K?<Odw'k
indexes = newint[count]; Yy;1N{dbT
for(int i = 0; i < count; i++){ Z`h_oK#y15
indexes = pageSize * 20xGj?M
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i; F,$$N>
} AyXKhj#Ml
}else{ 5N}|VGN
this.totalCount = 0; BP><G^
} y,eoTmaI
} TgG)btQ
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publicint[] getIndexes(){ <}>-ip?
return indexes; g(/O)G.
} Z19y5?uR
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publicvoid setIndexes(int[] indexes){ Tfs9<k>G#
this.indexes = indexes; j[
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} Ppn ZlGQ6
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publicint getStartIndex(){ d`*vJ#$>2
return startIndex; +K4v"7C
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} ^HKaNk<
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publicvoid setStartIndex(int startIndex){ ol>=tk 8}
if(totalCount <= 0) 6EGEwx
this.startIndex = 0; 3Jit2W4
elseif(startIndex >= totalCount) Eu_0n6J
this.startIndex = indexes C/#/F#C
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[indexes.length - 1]; BU .G~0
elseif(startIndex < 0) qoq<dCt3
this.startIndex = 0; 1Ee>pbd
else{ C8SNSeg
this.startIndex = indexes dNmX<WXG
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[startIndex / pageSize]; _$x *CP0(
}
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} 0a;zT
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publicint getNextIndex(){ Qx#)c%v\\
int nextIndex = getStartIndex() + dz DssAHy
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pageSize; r+obm)Qtp
if(nextIndex >= totalCount) zXO.NSC[
return getStartIndex(); uATRZMai
else UzRF'<TWf
return nextIndex; Lg53
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} Zz ?y&T
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publicint getPreviousIndex(){ TMs\#
int previousIndex = getStartIndex() - [r~lO@
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pageSize; {=Y&q~:8v
if(previousIndex < 0) CF4y$aC#
return0; $t?e=#G
else e1a %Rj~
return previousIndex; U%olH >1K
} [C#pMLp,~
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} n*|-"'j
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抽象业务类 u-<s@^YG
java代码: ot6Pq}
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/** !pXz-hxKT
* Created on 2005-7-12 ;W"[,#2TM
*/ r
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package com.javaeye.common.business; 3sNq3I
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import java.io.Serializable; hWJc
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import java.util.List; N:zSJW`1
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import org.hibernate.Criteria; y->iv%
import org.hibernate.HibernateException; h Nwb.[
import org.hibernate.Session; %dQX d]
import org.hibernate.criterion.DetachedCriteria; w,$1 7+]3
import org.hibernate.criterion.Projections; zAIC5fvu
import S^.=j
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org.springframework.orm.hibernate3.HibernateCallback; 'LI)6;Yc
import Plv+ mb
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org.springframework.orm.hibernate3.support.HibernateDaoS 2y,wN"qH*
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upport; cPYQ<Y=
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import com.javaeye.common.util.PaginationSupport; '%4,!
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public abstract class AbstractManager extends 19DW~kvYk
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HibernateDaoSupport { V-|}.kOH2
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privateboolean cacheQueries = false; F'!}$oT"
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privateString queryCacheRegion; +d96Z^KUhv
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publicvoid setCacheQueries(boolean Ws@s(5r
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cacheQueries){ HmKE>C/
this.cacheQueries = cacheQueries; ySZ)yT
} R(fR1
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publicvoid setQueryCacheRegion(String Q[^d{e*l
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queryCacheRegion){ vC1 `m
this.queryCacheRegion = (@9-"W
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queryCacheRegion; &~EOM
} |V5H(2/nk
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publicvoid save(finalObject entity){ ho. a93
getHibernateTemplate().save(entity); 4{=Em5`HbO
} M9nYt~vHX
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publicvoid persist(finalObject entity){ :KwYuwYS
getHibernateTemplate().save(entity); i|e-N?l
} ^q$sCt}
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publicvoid update(finalObject entity){ c"r( l~fc
getHibernateTemplate().update(entity); Bdi~B")
} :>z0m0nI\
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publicvoid delete(finalObject entity){ h";sQ'us
getHibernateTemplate().delete(entity); !% Md9Mu!o
} (nm&\b~j
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publicObject load(finalClass entity, TaH9Nu
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finalSerializable id){ Rh|&{Tf
return getHibernateTemplate().load ek<U2C_u#
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(entity, id); IZGty=Q_
} @NZ?D0"
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publicObject get(finalClass entity, Sk xaSJ"
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finalSerializable id){ Bs*s8}6
return getHibernateTemplate().get n$>H } #q
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(entity, id); SrxX-Hir
} sE% n=Ww
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publicList findAll(finalClass entity){ /C"E*a
return getHibernateTemplate().find("from a"EXR-+8
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" + entity.getName()); :hr%iu
} 8@!SM
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publicList findByNamedQuery(finalString G8@%)$A
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namedQuery){ pdM|dGq^
return getHibernateTemplate |"arVde
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().findByNamedQuery(namedQuery); zT@vji%Y
} mYZH]oo
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publicList findByNamedQuery(finalString query, (q
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finalObject parameter){ Mw <1
return getHibernateTemplate CR<*<=rI
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().findByNamedQuery(query, parameter); 1K!7FiqY
} (5SI!1N
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publicList findByNamedQuery(finalString query, (1ebE
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finalObject[] parameters){ *ood3M[M^
return getHibernateTemplate xf |=n
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().findByNamedQuery(query, parameters); HG3jmI+u>
} >%{h_5
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publicList find(finalString query){ ,ua]h8
return getHibernateTemplate().find :t(}h!7
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(query); P;h/)-q8
}
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publicList find(finalString query, finalObject +:D0tYk2B
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parameter){ MYu-[Hg
return getHibernateTemplate().find %
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(query, parameter); 0&<{o!>k
} @qeI4io-n
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public PaginationSupport findPageByCriteria ?P}7AF
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(final DetachedCriteria detachedCriteria){ n{M!l\1
return findPageByCriteria dz?:)5>I
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); :[Fwc
} )V3G~p=0
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public PaginationSupport findPageByCriteria T2k5\r8
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(final DetachedCriteria detachedCriteria, finalint _TH'v:C
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startIndex){ ]ko>vQ4]3
return findPageByCriteria `CW =*uBH
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(detachedCriteria, PaginationSupport.PAGESIZE, +3VY0J
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startIndex); %h^; "|Z
} ugOcK Gf
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public PaginationSupport findPageByCriteria (g5T2(_6L
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(final DetachedCriteria detachedCriteria, finalint d^4!=^HN
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pageSize, 233jT@Z
finalint startIndex){ uV{cvq$jy
return(PaginationSupport) &rjMGk"&
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getHibernateTemplate().execute(new HibernateCallback(){ s %/3X\_
publicObject doInHibernate 5E4np`J
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(Session session)throws HibernateException { (tys7og$'
Criteria criteria = =ayl~"bW
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detachedCriteria.getExecutableCriteria(session); b16\2%Ea1
int totalCount = zK?[6n89f
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((Integer) criteria.setProjection(Projections.rowCount %-> X$,Q
:
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()).uniqueResult()).intValue(); dQTJC
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criteria.setProjection z;D[7tT
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(null); `N;JM3 ck
List items = 1InG%=jLo
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criteria.setFirstResult(startIndex).setMaxResults 1ih|b8)Dn
7iT#dpF/A
(pageSize).list(); 0rooL<~fa
PaginationSupport ps = _>0I9.[5
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new PaginationSupport(items, totalCount, pageSize, bt"*@NJ$
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startIndex); x+47CDDu3
return ps; rdSkGb
} 0"LJ{:plz
}, true); 5@6F8:x}V
} ??)IPRv?yF
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public List findAllByCriteria(final k,OP*M
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DetachedCriteria detachedCriteria){ &i$p5
return(List) getHibernateTemplate )$XcO]
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().execute(new HibernateCallback(){ 2XNO*zbve
publicObject doInHibernate W:'H&`0
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(Session session)throws HibernateException { ^,*!Qk<c
Criteria criteria = BRyrdt*_e
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detachedCriteria.getExecutableCriteria(session); Z0 @P1
return criteria.list(); /'O?
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} nF`_3U8e
}, true); =~15q=XY0
} '9.L5*wh]
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public int getCountByCriteria(final ~x4]^XS
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DetachedCriteria detachedCriteria){ bdbTK8-
Integer count = (Integer) t}w<xe
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getHibernateTemplate().execute(new HibernateCallback(){ x5jd2wSDx
publicObject doInHibernate k nTCX
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(Session session)throws HibernateException { =^3 Z
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Criteria criteria = z>}H[0[#
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detachedCriteria.getExecutableCriteria(session); j2^Vz{
return V(wm?Cc]
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criteria.setProjection(Projections.rowCount (J}tCqP
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()).uniqueResult(); K-<<s
} <aSjK#
}, true); x`n7D
return count.intValue(); As"%
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} D6N32q@
} o@2Y98~Q}
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用户在web层构造查询条件detachedCriteria,和可选的 Ndmki
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <*_DC)&79
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PaginationSupport的实例ps。 yi.GD~69
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ps.getItems()得到已分页好的结果集 Jo'~oZ$
ps.getIndexes()得到分页索引的数组 (! a;}V<7
ps.getTotalCount()得到总结果数 03Uj0.Z|7
ps.getStartIndex()当前分页索引 MMU>55+-
ps.getNextIndex()下一页索引 i4Da 'Uk
ps.getPreviousIndex()上一页索引 E\1e8Wyh
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 jI/#NCKE
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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 }y>/#]X
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一下代码重构了。 fL(_V/p^
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我把原本我的做法也提供出来供大家讨论吧: >1BDt:G36
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首先,为了实现分页查询,我封装了一个Page类: yRy^'E~
java代码: Uc<BLu;
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/*Created on 2005-4-14*/ AB+HyZ*//
package org.flyware.util.page; \ lW*.<
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/** R!>l7p/|H)
* @author Joa 1EMrXnv,
* cC pNF `DN
*/ ]?sw<D{
publicclass Page { O^Y@&S RrQ
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/** imply if the page has previous page */ G?+0#?'Y
privateboolean hasPrePage; ~P fk
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/** imply if the page has next page */ )0o|u >
privateboolean hasNextPage; XyYP!<].C
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/** the number of every page */ {W'{A
privateint everyPage; Il]p >B
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/** the total page number */ \*mKctpz]6
privateint totalPage; jO.c>C[?
/ _Fi4wZ
/** the number of current page */ /u~L3Cp(
privateint currentPage; RDxvN:v
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/** the begin index of the records by the current ;"2(e7ir
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query */ jwp?eL!7
privateint beginIndex; Bq~?!~\?.
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/** The default constructor */ \7WZFh%:
public Page(){ lm8<0*;,
({<qs}H"
} | MXRNA~
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/** construct the page by everyPage o4H'
* @param everyPage ._p^0UxT
* */ 9gFfbvd
public Page(int everyPage){ 5Z_aN|Xn
this.everyPage = everyPage; _N"c,P0
} fBLR
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/** The whole constructor */ i\zN1T_
public Page(boolean hasPrePage, boolean hasNextPage, MZt&HbD-
Z8:'_#^@a[
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int everyPage, int totalPage, :+<GJj_d+
int currentPage, int beginIndex){ Ai~d
this.hasPrePage = hasPrePage; DfZ)gqp/Av
this.hasNextPage = hasNextPage; T^@P.zX
this.everyPage = everyPage; (,['6k<
this.totalPage = totalPage; b?:SCUI
this.currentPage = currentPage;
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this.beginIndex = beginIndex; &ER,;^H`6
} l(3\ekU!
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/** CTZ#QiNP
* @return :@,UPc-+
* Returns the beginIndex. ui&^ m,
*/ ]g]~!":
publicint getBeginIndex(){ %(~8a
return beginIndex; A}CpyRVCn
} U=N]XwjVK<
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/** sf,9Ym
* @param beginIndex p><DA fB
* The beginIndex to set. =UV=F/Af^
*/ (!koz'f
publicvoid setBeginIndex(int beginIndex){ }/VSIS@Z
this.beginIndex = beginIndex; 2(>=@q.1H
} eB5<N?;s
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/** zfA"xD
* @return `$>cQwB,D
* Returns the currentPage. +||[H)qym
*/ J
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publicint getCurrentPage(){ 2KSt4oa
return currentPage; s/OXZ<C|
} u`wT_?%w
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/** A5YS
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* @param currentPage <Q?_],ip
* The currentPage to set. l?zWi[Zf
*/ 6'JP%~QlS
publicvoid setCurrentPage(int currentPage){ C<hb{$@
this.currentPage = currentPage; \2AXW@xE
} TmdRB8N
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/** -P$E)5?^
* @return Yd$64d7,h
* Returns the everyPage. N0fXO
*/ nXxSv~r
publicint getEveryPage(){ 5h>t4 [~
return everyPage; /[Sy;wn
} UdX aC= Q
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/** 'q*:+|"
* @param everyPage E']Gh
* The everyPage to set. i
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*/ \:-N<[
publicvoid setEveryPage(int everyPage){ ATf{;S}
this.everyPage = everyPage; W'<cAg?
} ?p!+s96
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/** W'M\DKJ?
* @return fSzX /r
* Returns the hasNextPage. ZUUfn~ORc
*/ -cnlj
publicboolean getHasNextPage(){ g bwg3$!9
return hasNextPage; !Mk:rO-L
} ,__|SnA.
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/** o!M*cyq
* @param hasNextPage AZadNuL/
* The hasNextPage to set. T#w *5Qf
*/ d^jIsE `
publicvoid setHasNextPage(boolean hasNextPage){ cRC)99HP
this.hasNextPage = hasNextPage; N>_d {=P
} U-3uT&m*9.
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/** xn)r6
* @return &_y+hV{
* Returns the hasPrePage. %]@K}!)2
*/ DwC8?s*2H
publicboolean getHasPrePage(){ Eb=;D1)y]
return hasPrePage; T+|V;nP.
} 05m/iQ
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/** G.c@4Wz+
* @param hasPrePage ?4}EhXR(
* The hasPrePage to set. r.;(Kx/M
*/ =rDIU&0Y
publicvoid setHasPrePage(boolean hasPrePage){ u(|k/~\
this.hasPrePage = hasPrePage; =.Q|gZ
} zwKm;;v8
jZ>'q/
/** 2_HPsEx
* @return Returns the totalPage. ZW|VAn'>
* ^#L?HIM
*/ a4M`Bk;mb
publicint getTotalPage(){ R!.HS0i.
return totalPage; c~UYs\
} }qOC*k:
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/** 0IEFCDeCO
* @param totalPage ^R4eW|H
* The totalPage to set. <U$A_]*w
*/ ,/g\;#:{@]
publicvoid setTotalPage(int totalPage){ nNff~u)I
this.totalPage = totalPage; K*Tvo`
} v#`Wf}G
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} x 1"ikp}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 &p$SFH?s
t9()?6H\
个PageUtil,负责对Page对象进行构造: Xsc5@O!
java代码: HSOdqjR*
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/*Created on 2005-4-14*/ _r|$H_#
package org.flyware.util.page; (UV+/[,
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import org.apache.commons.logging.Log; W+~ w
import org.apache.commons.logging.LogFactory; .SdEhW15)
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/** "ppT<8Qi'
* @author Joa VPTT*a`
* RfB""b8]=
*/ =#<hT
s
publicclass PageUtil { 'gojP
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privatestaticfinal Log logger = LogFactory.getLog
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}x1mpPND
(PageUtil.class); %zyMWC
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/** <8At= U
* Use the origin page to create a new page m!:7ur:Y
* @param page >1tGQ
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* @param totalRecords 6Bp{FOj:Ss
* @return v|Tg %
*/ szwXr
publicstatic Page createPage(Page page, int K`FgU7g{
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totalRecords){ !DCJ2h%E[_
return createPage(page.getEveryPage(), m=S[Y^tR
|pp @
page.getCurrentPage(), totalRecords); HJ5m5':a
} lq_W;L
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/** As (C8C<
* the basic page utils not including exception GD'C^\EaZ
2`vCQV
handler Q[p0bD:
* @param everyPage 8'B\%.+"8e
* @param currentPage EBM\p+x&
* @param totalRecords 64\Z OG\,
* @return page ('uYA&9
*/ ooIMN =
publicstatic Page createPage(int everyPage, int >UJ&noUD#:
),\>'{~5&
currentPage, int totalRecords){ 1qUdj[Bj
everyPage = getEveryPage(everyPage); NI(`o8fN
currentPage = getCurrentPage(currentPage); "`"j2{9|e!
int beginIndex = getBeginIndex(everyPage, ^;s`[f|w
{7eKv+30
currentPage); H]=3^ g64
int totalPage = getTotalPage(everyPage, `CK;,>i
X{#@ :z$
totalRecords); ^^?DYC
boolean hasNextPage = hasNextPage(currentPage, 2ZtqZ64i
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totalPage); Lx?bO`=qg7
boolean hasPrePage = hasPrePage(currentPage); L238l
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returnnew Page(hasPrePage, hasNextPage, `z` `d*_
everyPage, totalPage, @mJN
currentPage, 9'toj%XQ
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beginIndex); 7^iF,N
} 6ddkUPTF
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privatestaticint getEveryPage(int everyPage){ m4Wn$Z
return everyPage == 0 ? 10 : everyPage; E}@8sY L
} pN0c'COy^
:
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privatestaticint getCurrentPage(int currentPage){ d<7J)zUm3
return currentPage == 0 ? 1 : currentPage; +H&_Z38n
} iW"L!t#\|
rpEFyHorJ
privatestaticint getBeginIndex(int everyPage, int +zs6$OI]V
6eDIS|/
currentPage){ GYO\l.%V5y
return(currentPage - 1) * everyPage; 4E
|6l
} iY|YEi8
GoEIY
privatestaticint getTotalPage(int everyPage, int -Ez|
f6L_uk`{
totalRecords){ {yb\p9q{Yo
int totalPage = 0; YRp\#pVnZ
o@>c[knJ
if(totalRecords % everyPage == 0) }=;>T)QmMO
totalPage = totalRecords / everyPage; R\.huOJh
else doR'=@ W
totalPage = totalRecords / everyPage + 1 ; (v4
5GJ0E Z'X
return totalPage; ;2@sn+@
} "]_|c\98
-/gS s<"
privatestaticboolean hasPrePage(int currentPage){ "DlCvjc
return currentPage == 1 ? false : true; .@6]_h;
} +cV!=gDT
(J$A
privatestaticboolean hasNextPage(int currentPage, K<]fElh-
T![K
i
int totalPage){ .897Z|$VB
return currentPage == totalPage || totalPage == 2 !;4mij,
g
Go
0 ? false : true; rp'fli?0e
} tt^ze|*&t
\PLV]%3,
<;6])
} D@^F6am%
bg
HaheU
KFZ[gqW8YY
QhGg^h%6
Rm*}<JN31
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。 y2 +a2
=O;SXzgE
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 jVA~]a
?UfZ VyHv+
做法如下: _"sRL}-Z
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 w@: ]]R
&1h3o^K
的信息,和一个结果集List: dJLJh*=AG
java代码: sd[QtK^
R82Y&s;
kH&ZPAI
/*Created on 2005-6-13*/ fjWh}w8
package com.adt.bo; \9}5}X_x.
'.K,EM!-~h
import java.util.List; Wl#^Eu\g1W
Z>,X$Y6<
import org.flyware.util.page.Page; (t]>=p%4g
wi9|
/** Q
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* @author Joa Yjl0Pz.q
*/ }-L@AC/\#
publicclass Result { 5{g9Wh[
JG<3,>@%
private Page page; /J+)P<_ A
S!q}Pn
private List content; Lq [wabF
%8*d)AB:
/** `e9uSF:9C
* The default constructor ;:|KfXiC8
*/ $McO'Bye{h
public Result(){ 'i(p@m<'
super(); Qwa"AY5pW
} ?8, N4T0)
+wUhB\F
*
/** Dgm%Ng
* The constructor using fields d>`(.qvxR
* if}]8
* @param page rl^LSz
* @param content H n!vTB
*/ h(8;7}K
public Result(Page page, List content){ o3yqG#dA
this.page = page; (7b_g6>:
this.content = content; ]-'9|N*}l
} wY.g-3
i/J NG
/** %^l&fM*
* @return Returns the content. +zdkdS,2<
*/ +r$.v|6
publicList getContent(){ /
3k\kkv!
return content; 5lxq-E3
} z{g<y^Im+E
I7PWOd
/** 5tU"|10m3
* @return Returns the page. @c!67Z
*/ 4) 3pa*
public Page getPage(){ v,+l xY
return page; !5OMAWNU@
} ^.C X6%
'r n;|K
/** j_yFH#^W:
* @param content w)eQ'6Vu
* The content to set. )t0b$<%
*/ ptv4v[gQ
public void setContent(List content){ %9/)
this.content = content; {@ y,
} ^R7z LHU;
H27Oq8
/** j$|C/E5?
* @param page r65NKiQD
* The page to set. 3Gl]g/
*/ otSPi7|k
publicvoid setPage(Page page){ C5 5n
this.page = page; Kg`x9._2
} 7=.VqC^
} pmyM&'#Id
Au._n,<
+@uC:3jM
^Ai_/! "
&&nO]p`
2. 编写业务逻辑接口,并实现它(UserManager, p\_qHq\;j
GLQvAHC
UserManagerImpl) '%!M>rY,
java代码: =Xjuz:9D~
r)5\3j[P
'(pdk
/*Created on 2005-7-15*/ d+2O^of:T
package com.adt.service; J8v:a`bX&
7oe@bS/Z
import net.sf.hibernate.HibernateException; M y"!j,Up
C9g~l}=$&
import org.flyware.util.page.Page; 0^&R7Rv c
xnQGCw?S&}
import com.adt.bo.Result; O4PdN?
e~s7ggg2k
/** '+I
2$xE
* @author Joa K}=8:BaUL
*/ UVCMB_T
publicinterface UserManager { .&Pe7`.BE
i5<Va@ru!s
public Result listUser(Page page)throws Wx|6A#cg!
<oaBh)=7
HibernateException; :z} _y&]
~<aeA'>OA
} +Q!xEfpO;
Fl+tbF
]<;i}n|
<
txfwLqx
Q xF8=p
java代码: @oqi@&L'C
"4k=(R?
"">fn(
/*Created on 2005-7-15*/ 9poEUjBI
package com.adt.service.impl; 8P<UO
"p~]m~g
import java.util.List; 88np/jvC{
8@W/43K8-
import net.sf.hibernate.HibernateException; dI
ZTLb"a
%QsSR'`
import org.flyware.util.page.Page; mf]( 3ZL
import org.flyware.util.page.PageUtil; X\^& nLa
svq9@!go
import com.adt.bo.Result; t2-nCRXEP
import com.adt.dao.UserDAO; k`7.p,;}U
import com.adt.exception.ObjectNotFoundException; zUEfa!#?
import com.adt.service.UserManager; 4=F]`Lql
`\|3
~_v
/** KB,~u*~!
* @author Joa @Uj_+c
q
*/ t1:S!@
publicclass UserManagerImpl implements UserManager { 4'{hI;&a&
3^A/`8R7K
private UserDAO userDAO; ,F?~'-K
i9@;,4f
/** b ?2X>QJ
* @param userDAO The userDAO to set. ;+ Co!L
*/ ^0-e,d
9h
publicvoid setUserDAO(UserDAO userDAO){ sPE)m_u
this.userDAO = userDAO; yrE,,N%I
} w-'D*dOi
_5U%'\5s
/* (non-Javadoc) fs3-rXoB
* @see com.adt.service.UserManager#listUser CVGOX z
(|36!-(iK
(org.flyware.util.page.Page) y800(z
*/ nT@6g|!
public Result listUser(Page page)throws orQV'
17n+4J]
HibernateException, ObjectNotFoundException { V^Mf4!A(y
int totalRecords = userDAO.getUserCount(); wKi}@|0[@
if(totalRecords == 0) {Ukc D+.Y
throw new ObjectNotFoundException }[KDE{,V
6&
&} P79
("userNotExist"); A1|7(Sow
page = PageUtil.createPage(page, totalRecords); A^4kYOe
List users = userDAO.getUserByPage(page); EBIa%,
returnnew Result(page, users); ~D-JZx
} fNAo$O4cm
0[2BY]`Z.
} w`.T/
X #p o|,Q
G>[
NZE
BS-:dyBw
! =\DC,-CB
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 re ]Ste
~E<PtDab
询,接下来编写UserDAO的代码: ;*wT,2;
3. UserDAO 和 UserDAOImpl: <*A|pns
java代码: n?ZL"!$
o%/-5-
]{Mci]H6T
/*Created on 2005-7-15*/ <uBhi4
package com.adt.dao; #Cg}!38
G. -h=DT]
import java.util.List; q:2aPfo&
*;OJ~zT
import org.flyware.util.page.Page; [V> :`?
)p/=u@8_f
import net.sf.hibernate.HibernateException; 3WO#^}t
t?]\M&i&
/** 55>" R{q
* @author Joa +7i7`'9pd
*/ I=4Xv<F
publicinterface UserDAO extends BaseDAO { 8 l'bRyuS
>bX-!<S
publicList getUserByName(String name)throws b(.-~c('
Xr@l+zr
HibernateException; ih+*T1#:(
dN]Zs9]
publicint getUserCount()throws HibernateException; fCt^FU
/RJ6nmN@}
publicList getUserByPage(Page page)throws cX|[WT0[I
.%x"t>]
HibernateException; ?qd,>
i\kTm?BQZ
} F,p`-m[q
DEUd[
`G=ztL!gq
H4PbO/{xO
toS(UM n
java代码: Q vv\+Jp^
p3M#XC_H]
rxs~y{Xi
/*Created on 2005-7-15*/ Kcscz,
package com.adt.dao.impl; /v}P)&
zuC 58B
import java.util.List; <ICZ"F`S
1A7 %0/K-]
import org.flyware.util.page.Page; lv<iJH\
kq) +@p
import net.sf.hibernate.HibernateException; 1s{ISWm
import net.sf.hibernate.Query; u @{E{
pY+.SuM
import com.adt.dao.UserDAO; 7ei>L]gm%
Q!4i_)rM
/** ${A5-
* @author Joa G0_&gx`
*/ ,{.zh&=4
public class UserDAOImpl extends BaseDAOHibernateImpl U0NOU#
:V&N\>Wo
implements UserDAO { [D*J[?yt
+3M$3w{2
/* (non-Javadoc) eV[`P&j_C
* @see com.adt.dao.UserDAO#getUserByName P'a0CE%
qn2o[x
(java.lang.String) E:u ReT
*/ t{/hkXq]
publicList getUserByName(String name)throws ,sO:$
(H&@u9K?a?
HibernateException { qSFc=Wwc
String querySentence = "FROM user in class vVI6m{zYV
j2RRSz&9
com.adt.po.User WHERE user.name=:name"; [leW/2i
Query query = getSession().createQuery Um]p&phVL
H7{Q@D8
(querySentence); %xf)m[JU=
query.setParameter("name", name); IZv~[vi_
return query.list(); 8|1`Tn}o
} 5;X {.2
c u\ls^
/* (non-Javadoc) 2{Wo-B,wt~
* @see com.adt.dao.UserDAO#getUserCount() 7m@
)Lv
*/ Ihdu1]~R{
publicint getUserCount()throws HibernateException { Gs+\D0o!
int count = 0; ANckv|&'v
String querySentence = "SELECT count(*) FROM 4rI:1yGt@
?k
[%\jq{a
user in class com.adt.po.User"; aRbx
Query query = getSession().createQuery lkV6qIj
"e~k-\^Y
(querySentence); S3SV.C:z>
count = ((Integer)query.iterate().next 'I&|1I^
,`;jvY~Ec
()).intValue(); ./#e1m?.
return count; 'dkXYtKCB
} #2h+dk$1
Ds{{J5Um%
/* (non-Javadoc) i\(\MzW*'
* @see com.adt.dao.UserDAO#getUserByPage M(qxq(#{U
PKi_Zh.D
(org.flyware.util.page.Page) GtF2@\
*/ Z`rK\Bc
publicList getUserByPage(Page page)throws >4,{6<|
%PzQ\c
HibernateException { 'nMApPl
String querySentence = "FROM user in class A^pu
p?;-!TUv
com.adt.po.User"; ;_iPm?Y8
Query query = getSession().createQuery -<_7\09
ue@8voZhS/
(querySentence); +W6Hva.
query.setFirstResult(page.getBeginIndex()) ,*7H|de7
.setMaxResults(page.getEveryPage()); Am=wEu[b
return query.list(); \@i=)dA
} =K:(&6f<t
\ZS\i4
} w TlGJ$D0
sYI~dU2H
QjLji+L
!(Q l)C
nB=0T`vQ
至此,一个完整的分页程序完成。前台的只需要调用 YZibi
~uB'3`x
userManager.listUser(page)即可得到一个Page对象和结果集对象 DR6]-j!FK
qh-[L
的综合体,而传入的参数page对象则可以由前台传入,如果用 Qu`n&
rnu
e(t
webwork,甚至可以直接在配置文件中指定。 k_!+V`Ro#
~wTX>qV
下面给出一个webwork调用示例: X:Q$gO?[4
java代码: gA_krK,Z
vVAb'`ysv
7$
d}!S
/*Created on 2005-6-17*/ qbXz7s*{
package com.adt.action.user; fE^uF[-7?
job[bhK'Jt
import java.util.List; sAVefL?
@&5 A&(
import org.apache.commons.logging.Log; 4b4QbJ$
import org.apache.commons.logging.LogFactory; aM$\#Cx
import org.flyware.util.page.Page; eaQ90B4
f/ajejYo?,
import com.adt.bo.Result; AliRpxxd
import com.adt.service.UserService; 84'?um
import com.opensymphony.xwork.Action; O-j$vzHpdY
{7X#4o0
/** 2Pp&d>E4
* @author Joa |6%.VY2b
*/ "V3}t4
publicclass ListUser implementsAction{ .B>B`q;B
%,|ztH/ Q
privatestaticfinal Log logger = LogFactory.getLog t^.'>RwW|
)Pli})
(ListUser.class); vBNZ<L\|a
&8sV
o@Pa
private UserService userService; k(vPg,X>m
Zm(dY*z5:J
private Page page; &EovZ@u
Fd7*]a
privateList users; G
AQ
'Ti1!
8.?E[~
/* , H2YpZk
* (non-Javadoc) ANMYX18M
* <*u C
* @see com.opensymphony.xwork.Action#execute() bD<qNqX$
*/ }E; F)=E
publicString execute()throwsException{ S5_t1wqBJ
Result result = userService.listUser(page); wVqd$nsY"
page = result.getPage(); :
,p||_G&
users = result.getContent(); bC~~5Cm
return SUCCESS; Q2/.6O8
} ~Fw<eY
] TSg!H
/** m_*R.a
* @return Returns the page. .#fPw_i
*/ :[sOKV i
public Page getPage(){ =XT)J6z^"
return page; TY.F pW
} ,=o0BD2q
t};~H\:
/** 2yKz-"E
* @return Returns the users. $%PVJs
*/ D|_V<'
publicList getUsers(){ gWrAUPS[
return users; %y"J8;U
} vG
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"+|L_iuNQ
/** s&'BM~WI
* @param page !gH9 ay
* The page to set. ~O;y?]U
*/ hazq#J!
publicvoid setPage(Page page){ @(:v_l
this.page = page; hVP
IHQt
} n#*`!#
~|lIC !q
/** kIvvEh<L=
* @param users <\@1Zz@ms
* The users to set. }B q^3?,#{
*/ 47UO*oLS
publicvoid setUsers(List users){ T&xt`|
this.users = users; MJ\[Dt
} ?_q+&)4-o
9<s4yZF@x
/** ~]WVG@-
* @param userService ,P6=~q3k
* The userService to set. aMK~1]Cx
*/ 5H lWfD
publicvoid setUserService(UserService userService){ ksWSMxm
this.userService = userService; a<m-V&4x
} h qmSE'8
} [s`
G^
?4[H]BK
:\yc*OtX
u3ZCT" !
DQJG,?e{
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, &mE?y%
](K0Fwo`;"
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 LJQJ\bT?
Cca0](R*&
么只需要: 8o-bd_
java代码: _:J*Cm[q
Z$'IBv
]gEhE
<?xml version="1.0"?> Owf.f;QR
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )1F<6R
,EEPh>cXc
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $%2H6Eg0
/_\W+^fE
1.0.dtd"> #cKqnk
j@1)K3Hga
<xwork> fgF;&(b
Ec]|p6a3
<package name="user" extends="webwork- o6}n8U}bk
~}% ~oT
interceptors"> ?m;;D'1j
RuAlB*
<!-- The default interceptor stack name Kt/)pc
AQ{zx1^2>K
--> V#83!
<default-interceptor-ref +F@_Es<6
`UzVS>]l[+
name="myDefaultWebStack"/>
=P^wh
+S~.c;EK
<action name="listUser" 9E1W|KE
IA*KaX2S<
class="com.adt.action.user.ListUser"> x?r1s#88>
<param K7`YJp`i
P $>`
name="page.everyPage">10</param> ?tYpc_p#
<result UAYd?r
rwqv V^
name="success">/user/user_list.jsp</result> / 8gL.i$
</action> &35|16z%@
8SmjZpQ?
</package> UG[e//m
w+AuMc
</xwork> dpzw.Z
;IZ?19Q
g]$
4~"|.
<{ru|-9
K5"sj|d&
d"THt}
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 Q9>U1]\
(f1M'w/OD
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。 q<{NO/Mm
O`W%Tr
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 H[Weu
6yIvaY$KR
n2ndjE$
0SV \{]2
`
2%6V)s
我写的一个用于分页的类,用了泛型了,hoho ,x_Z JL
K"{HseN{
java代码: RKkGITDk
^toAw8A=@0
:FQ1[X1xm
package com.intokr.util; pY}/j;.[
U;^[$Aq
import java.util.List; )0CQP
H;KDZO9W
/** @Hjea1@t
* 用于分页的类<br> 8X7{vN_3K
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #hxyOq,
* &0v.E"0<
* @version 0.01 46,j9x
* @author cheng f_6`tq m%
*/ Nhf~PO({&
public class Paginator<E> { wNQqfqZ
privateint count = 0; // 总记录数 G=d(*+&
B
privateint p = 1; // 页编号 5nLDj:C~
privateint num = 20; // 每页的记录数
,=%nw]:
privateList<E> results = null; // 结果 }Uw#f@Wh
>bm|%Ou"
/** Ewo~9
4{
* 结果总数 1]OSWCEm*[
*/ UuJjO^t
publicint getCount(){ *^XbDg9
return count; (GU9p>2
} lAASV{s{
WS0JS'
publicvoid setCount(int count){ TT}]wZ
this.count = count; p2pAvlNoF
} JWHSnu!
r|R7-HI
/** :#X[%"g.
* 本结果所在的页码,从1开始 <+]f`c*Z
* q&si%
* @return Returns the pageNo. _PXdzeI.
*/ 3C^1frF
publicint getP(){ ~!:0iFE&H
return p; \L]|-f(4
} <$Yi]ty
f} K`Jm_}?
/** l I-p_K
* if(p<=0) p=1 =xl~][
* zICI_*~
* @param p 8k!6b\Imz
*/ 6`e@$(dfA
publicvoid setP(int p){ }vh Za p^
if(p <= 0) k3hkk:W
p = 1; Ill[]O
this.p = p; yp]@^T N
} z;3NiY
]|Z b\{
/** 9O98Q6-s
* 每页记录数量 <@#PF$!
*/ 2C
"=!'
publicint getNum(){ M<`|CVl
return num; d ,F5:w&
} #@//7Bf%
~L?nq@DL
/** n^9 ?~
* if(num<1) num=1 )|]dmQ-
*/ zK5bO=0j
publicvoid setNum(int num){ .{so
if(num < 1) 1mW %
num = 1; hu@7?f_"L/
this.num = num; YD_]!HK}
} AFm1t2,+;
Y
62r
/** uHM@h{r
* 获得总页数 >L>+2z
*/ D3]BTkMMS;
publicint getPageNum(){ HD-Erop
return(count - 1) / num + 1; XD%wj
} 46XN3r
284zmZZ
/** 96Zd M=
* 获得本页的开始编号,为 (p-1)*num+1 ltA/
*/ e3(<8]`b[
publicint getStart(){ \"^%90F
return(p - 1) * num + 1; ]((i?{jb(
} `a4 $lyZ
RQ'
H!(K
/** J=}F2C
* @return Returns the results. vXcy#
*/ 7_)|I?
=0d
publicList<E> getResults(){ ZF{~ih*^u
return results; .[j%sGdKl
} v '9m7$
AK/:I>M
public void setResults(List<E> results){ wK*PD&nN
this.results = results; ]0~qi@
} bBE+jqi2
Y1\K;;X
public String toString(){ {B{i(6C(
StringBuilder buff = new StringBuilder j\2[H^
n["
9|
(); []}N
buff.append("{"); A,XfD} +:Z
buff.append("count:").append(count); Ja [ 4A0.
buff.append(",p:").append(p); ]PX}b
buff.append(",nump:").append(num); Z)9R9s
buff.append(",results:").append %e=!nRc
T\sNtdF`:
(results); (B#(Z=
buff.append("}"); dOXD{c
return buff.toString(); x ^vt; $
} <r\I"z$
p:[LnL
} DeQDH5X"
3%
vis\~^
XB/'u39