Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XnQo0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 M ,8r{[2
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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 ;jTP|q?|{
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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 @U%I 6 t
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分页支持类: jl=<Q.Mm7
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java代码: /GNRu
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package com.javaeye.common.util; tZ[Y~],F
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import java.util.List; `av8|;
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publicclass PaginationSupport { iZQwo3"8r
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publicfinalstaticint PAGESIZE = 30; l/_3H\iM
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privateint pageSize = PAGESIZE; 0CxQ@~ttl
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privateList items; lkV%
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privateint totalCount; gO?+:}!
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privateint[] indexes = newint[0]; pK#Ze/!
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privateint startIndex = 0; hNXPm~OK\
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public PaginationSupport(List items, int 1<^"OjQ
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totalCount){ 0i9y-32-
setPageSize(PAGESIZE); jNV2o
setTotalCount(totalCount); 'z2}qJJ)
setItems(items); W?G4\ubM3<
setStartIndex(0); abUn{X+f~
} (
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public PaginationSupport(List items, int y>u+.z a|
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totalCount, int startIndex){ ~ @Ib:M
setPageSize(PAGESIZE); Bm%:Qc*
setTotalCount(totalCount); xmTa$tR+
setItems(items); MwL'
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setStartIndex(startIndex); `pN"T?Pk
} d5]9FIj
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public PaginationSupport(List items, int xUPM-eF=
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totalCount, int pageSize, int startIndex){ z?h\7
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setPageSize(pageSize); J}TS-j0
setTotalCount(totalCount); +M
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setItems(items); UKQ,]VC
setStartIndex(startIndex); R3Eh47
} 5SK{^hw
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publicList getItems(){ }+QgRGQ
return items; (80]xLEBL
} 31wact^
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publicvoid setItems(List items){ B @UaaWh
this.items = items; 'rRo2oTN
} O$Wt\Y<q
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publicint getPageSize(){ 4>{q("r,
return pageSize; n<kcK
} t</rvAH E
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publicvoid setPageSize(int pageSize){ ?
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this.pageSize = pageSize; x';6
} <[?oP[ j
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publicint getTotalCount(){ d37l/I
return totalCount; T%KZV/
} %]>c4"H
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publicvoid setTotalCount(int totalCount){ +XJj:%yt
if(totalCount > 0){ KB7CO:
this.totalCount = totalCount; 9<WMM)
int count = totalCount / f/?#
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pageSize; -f z
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if(totalCount % pageSize > 0) .jZmQtc
count++; >;nE.]
indexes = newint[count]; [U]*OQH`e
for(int i = 0; i < count; i++){ uezqC=v$h
indexes = pageSize * mmAikT#k
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} VCcLS3
}else{ $91c9z;f^
this.totalCount = 0; D.j'n-yw
} - P1OD)B
} ~o= Sxaf
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publicint[] getIndexes(){ z;GnQfYG
return indexes; Eg 5|XV
} &iR>:=ksN
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publicvoid setIndexes(int[] indexes){ CwTx7
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this.indexes = indexes; ._~_OVU
} (X,Ua+{
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publicint getStartIndex(){ vO%n~l=
return startIndex; p8oOm>B96n
} R(kr@hM
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) 0V"r$7(}
this.startIndex = 0; >1,.4)k%K
elseif(startIndex >= totalCount) )(9>r/bq
this.startIndex = indexes ?&_ -,\t
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[indexes.length - 1]; J i :2P*
elseif(startIndex < 0)
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this.startIndex = 0; V2,54YE
else{ PSI5$Vna4p
this.startIndex = indexes wRgmw
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[startIndex / pageSize]; \s<{V7tq
} 2w'Q9&1~
} 0_}OKn)J
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publicint getNextIndex(){ BZ">N
int nextIndex = getStartIndex() + Ha@'%<gFe
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pageSize; 1% ]|O
if(nextIndex >= totalCount) %UI.E=`n
return getStartIndex(); Lz2wOB1Zc+
else *j?tcxq
return nextIndex; ?!U=S=8
} }BKEz[G(
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publicint getPreviousIndex(){ l{>fma]7
int previousIndex = getStartIndex() - Uy5IvG;O+
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pageSize; 2BXpk^d5y
if(previousIndex < 0) z~L''X7g
return0; }Xr-xh\v
else w0)V3
return previousIndex; 4[
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} UZi^ &
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} zIi|z}WJ
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抽象业务类 dQYb)4ir
java代码: V8ZE(0&II}
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/** {(w/_C9
* Created on 2005-7-12 =${]j
*/ Yc3\NqQM
package com.javaeye.common.business; !jN}n)FSq
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import java.io.Serializable; 1 "?KQU
import java.util.List; k*(c8/<.d
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import org.hibernate.Criteria; gS _)(
import org.hibernate.HibernateException; vp?87h
import org.hibernate.Session; t
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import org.hibernate.criterion.DetachedCriteria; '3 w=D
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import org.hibernate.criterion.Projections; "^F#oo%L
import NeAkJG=<
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org.springframework.orm.hibernate3.HibernateCallback; Y ( x_bJ
import U&yXs'3a&
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org.springframework.orm.hibernate3.support.HibernateDaoS QG*=N {%5
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upport; `uM:>
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import com.javaeye.common.util.PaginationSupport; hEi]-N\X
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public abstract class AbstractManager extends au@ LQxKQ
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HibernateDaoSupport { k{;"Aj:iL
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privateboolean cacheQueries = false; ye:pGa w
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privateString queryCacheRegion; e:fp8 k<
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publicvoid setCacheQueries(boolean PElC0qCn[
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cacheQueries){ Xf!@uS6<X
this.cacheQueries = cacheQueries; X1&Ug^
} <nlZ?~%}
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publicvoid setQueryCacheRegion(String [bk2RaX:i
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queryCacheRegion){ Tm(XM<
this.queryCacheRegion = #no~g(!o
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queryCacheRegion; fOJ0#^Z
} zs
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publicvoid save(finalObject entity){ %KHO}gad1
getHibernateTemplate().save(entity); 8@]*X,umc
} k4fc5P
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publicvoid persist(finalObject entity){ BZejqDr*
getHibernateTemplate().save(entity); F-[zuYGp
} 7[h_"@_A7
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publicvoid update(finalObject entity){ &[:MTK?x!
getHibernateTemplate().update(entity); ;Pf
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} sd9$4k"
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publicvoid delete(finalObject entity){ F1) B-wW
getHibernateTemplate().delete(entity); vQ/}E@?u
} yI/2 e [
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publicObject load(finalClass entity,
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finalSerializable id){ EBlfwFd
return getHibernateTemplate().load yTzP{I
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(entity, id); c.-h'1
} j[l6&eX
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publicObject get(finalClass entity, WA}<Zme3[
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finalSerializable id){ OzY55
return getHibernateTemplate().get =sy>_
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(entity, id); U"$Q$ OFs
} Ck;O59A"&-
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publicList findAll(finalClass entity){ BC*vG=a
return getHibernateTemplate().find("from arJ4^ d
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" + entity.getName()); pm$2*!1F(
} K*iy ^}
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publicList findByNamedQuery(finalString d\aKGq;8C
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namedQuery){ = ms(dr^n
return getHibernateTemplate Rs_0xh
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().findByNamedQuery(namedQuery); Ww5c9orXn
} b ~DtaGh
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publicList findByNamedQuery(finalString query, PN9^ sLx=
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finalObject parameter){ j
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return getHibernateTemplate {Hncm
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().findByNamedQuery(query, parameter); . K`OEdr<
} wKF #8Y
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publicList findByNamedQuery(finalString query, Gr9/@U+
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finalObject[] parameters){ Fe
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return getHibernateTemplate }L
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().findByNamedQuery(query, parameters); 1HQh%dZZ
} ",/3PT
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publicList find(finalString query){ kk]f*[Zi5
return getHibernateTemplate().find gXr"],OM;
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(query); ~RcI+jR)
} 5/x"!Jk
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publicList find(finalString query, finalObject BiGB<Jr
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parameter){ VBc[(8o
return getHibernateTemplate().find 7sP;+G
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(query, parameter); \b{Aj,6,
} u I$|M
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public PaginationSupport findPageByCriteria s_]p6M
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(final DetachedCriteria detachedCriteria){ 2|'v[
return findPageByCriteria WrK!]17or
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); NGYliP,.6
} 5dffFe
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public PaginationSupport findPageByCriteria u\YH,
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(final DetachedCriteria detachedCriteria, finalint B$~oZ'4v
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startIndex){ 4d&#NP
return findPageByCriteria {FzL@!||
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(detachedCriteria, PaginationSupport.PAGESIZE, /dTy%hZC}
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startIndex); (]7*Kq
} d,=Kv
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public PaginationSupport findPageByCriteria ?pgdj|"a
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(final DetachedCriteria detachedCriteria, finalint CU=}]Y
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pageSize, +|.}oL^}G
finalint startIndex){ !_GY\@}
return(PaginationSupport) 4)D#kP
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getHibernateTemplate().execute(new HibernateCallback(){ Zu(eYH=Q
publicObject doInHibernate ~~:w^(s9
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(Session session)throws HibernateException { ~ILig}I
Criteria criteria = ;9r
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detachedCriteria.getExecutableCriteria(session); @rs(`4QEh
int totalCount = R"(rL5j
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((Integer) criteria.setProjection(Projections.rowCount ?f v?6r
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()).uniqueResult()).intValue(); h&4ufx6
criteria.setProjection v +-f
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(null); f`<j(.{9F
List items = _3$@s{k-TI
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criteria.setFirstResult(startIndex).setMaxResults `B+%W
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(pageSize).list(); 0P`wh=")
PaginationSupport ps = `mPmEV<
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new PaginationSupport(items, totalCount, pageSize, 9fD4xkRS
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startIndex); Hh @q;0ni
return ps; Mr'}IX5
} M ,V+bt
}, true); HE&,?vioy
} #QJ
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public List findAllByCriteria(final $,08y
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DetachedCriteria detachedCriteria){ *Yv"lB8
return(List) getHibernateTemplate 2&91C[da0
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().execute(new HibernateCallback(){ E
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publicObject doInHibernate m1_?xU
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(Session session)throws HibernateException { P8NKpO\
Criteria criteria = >JT{~SRB|Y
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detachedCriteria.getExecutableCriteria(session); FzmCS@yA
return criteria.list(); 5A 1oZ+C#
} RsBo\#`
}, true); oR}ir
} y8: 0VZox
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public int getCountByCriteria(final 4W8rb'B!Ay
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DetachedCriteria detachedCriteria){ IV^LYu
Integer count = (Integer) XuJwZN!(
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getHibernateTemplate().execute(new HibernateCallback(){ lEi,duS)
publicObject doInHibernate oTtmn,
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(Session session)throws HibernateException { >7!aZO
Criteria criteria = _dqjRhu
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detachedCriteria.getExecutableCriteria(session); rh2pVDS
return FW7+!A&F
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criteria.setProjection(Projections.rowCount pH#&B_S6z=
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()).uniqueResult(); :b>Z|7g ?
} BEvSX|M>x
}, true); n? "ti
return count.intValue(); .G+}Kn9!
} ~l!(I-'?g
} aM 0kV.O
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用户在web层构造查询条件detachedCriteria,和可选的 (Wr;:3i
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8DTk<5mW~
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PaginationSupport的实例ps。 `.aL>hf
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ps.getItems()得到已分页好的结果集 567ot|cc
ps.getIndexes()得到分页索引的数组 f[7'kv5S
ps.getTotalCount()得到总结果数 t^?8Di\
ps.getStartIndex()当前分页索引 E E?v~6"&
ps.getNextIndex()下一页索引 A`(p6 H"s
ps.getPreviousIndex()上一页索引 bI[!y#_z4
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }SitT\%
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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 5K'EuI)
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一下代码重构了。 rQ}4\PTi
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我把原本我的做法也提供出来供大家讨论吧: PB>p"[ap4
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首先,为了实现分页查询,我封装了一个Page类: N(vbo
java代码: OpxVy _5,
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/*Created on 2005-4-14*/ u-UUF
package org.flyware.util.page; mk\U wv
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/** {DN c7G
* @author Joa rShi"Yw
* ?]fBds=
*/ $O}gl Q
publicclass Page { IX7d[nm39
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/** imply if the page has previous page */ ?P`wLS^;
privateboolean hasPrePage; 0O-p(L=
9Z*` {
/** imply if the page has next page */ R5]R
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privateboolean hasNextPage; %h|z)
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/** the number of every page */ |D]jdd@!a2
privateint everyPage; q4Ye
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/** the total page number */ KH pxWq
privateint totalPage; $#R.+B
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/** the number of current page */ w2{k0MW
privateint currentPage; /2'\ya4B
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/** the begin index of the records by the current eg(xN/D
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query */ );))kYr
privateint beginIndex; zN5i}U=|r
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/** The default constructor */ yE"hgdL
public Page(){ )W 57n)]
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} 8.k"kXU@n
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/** construct the page by everyPage 0@AK
* @param everyPage (59<Zo
* */ yv3myaS
public Page(int everyPage){ |lJXI:GG
this.everyPage = everyPage; /2l4'Q=
} r}hj,Sq'
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/** The whole constructor */ ?-@hNrx
public Page(boolean hasPrePage, boolean hasNextPage,
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int everyPage, int totalPage, B/5C jHz
int currentPage, int beginIndex){ ev8E.ehD
this.hasPrePage = hasPrePage; }1R k]$XC
this.hasNextPage = hasNextPage; { +C>^b
this.everyPage = everyPage; QJ"Bd`wc
this.totalPage = totalPage; vpXS!o>/Sn
this.currentPage = currentPage; 2YwV}
this.beginIndex = beginIndex;
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} {xM%3
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/** Q;5\( 0w5
* @return $oxPmELtpe
* Returns the beginIndex. *39sh[*}
*/ 3N]pN<3@
publicint getBeginIndex(){ _&F6As
!{
return beginIndex; /o|@]SAe.
} e'\I^'`!M
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/** ir]u FOj
* @param beginIndex R4IFl
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* The beginIndex to set.
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*/ 3I"&Qp%2
publicvoid setBeginIndex(int beginIndex){ K]
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this.beginIndex = beginIndex; k.lnG5e
} mD )Nh
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/** a?JU(
* @return x(S064
* Returns the currentPage. tY[y? DJ
*/ *\joaw
publicint getCurrentPage(){ l,v:[N
return currentPage; x7NxHTL
} RIJBHOa
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/** |xf%1(Rl@
* @param currentPage |Cen5s
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* The currentPage to set. H<NYm#a"
*/ 1/&j'B
publicvoid setCurrentPage(int currentPage){ P%/+?(?
this.currentPage = currentPage; "V9!srIC
} zZf#E@=$|
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/**
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* @return z4f5@
* Returns the everyPage. LG,RF:
*/ e,4!/|H:
publicint getEveryPage(){ =r_ SMTu
return everyPage; Xp{gh@#dr
} QPFpGS{d
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/** @x=CMF15
* @param everyPage "n8_Ag@r
* The everyPage to set. CLYcg$V
*/ nEGku]pCH{
publicvoid setEveryPage(int everyPage){ Q`//HOM,
this.everyPage = everyPage; G)e 20Mst
} /4T%s
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/** 94a_ W9
* @return ,]cd%w9
* Returns the hasNextPage. D:F!;n9
*/ AVcZ.+?
publicboolean getHasNextPage(){ SU#|&_wtr!
return hasNextPage; { j/w3
} KK] >0QAY
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/** pixI&iQ
* @param hasNextPage ' l!QGKz
* The hasNextPage to set. lhjPS!A~
*/ |QzPY8B9O
publicvoid setHasNextPage(boolean hasNextPage){ *}v'y{;
this.hasNextPage = hasNextPage; T4f:0r;^f*
} mWGT
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/** 5S7Z]DXiT8
* @return CY7REF
* Returns the hasPrePage. v(t&8)Uu
*/ |
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publicboolean getHasPrePage(){ I+<; Dsp
return hasPrePage; =k8A7P
} 3AB5Qs<
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/** keWgbj
* @param hasPrePage
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* The hasPrePage to set. K3Xy%pqR#
*/ *Z0}0<
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publicvoid setHasPrePage(boolean hasPrePage){ @+2Zt%
this.hasPrePage = hasPrePage; %(e=Q^=
} _ Po9pZ
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/** 6@$[x* V
* @return Returns the totalPage. K{iayg!k
* *1%g=vb
*/ {Ise (>V
publicint getTotalPage(){ \agC Q&
return totalPage; TxiJ?sDh*
} DBv5Og
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/** L*l( ~t)vF
* @param totalPage V*TG%V -
* The totalPage to set. 1rKR=To
*/ .DX#:?@4@Y
publicvoid setTotalPage(int totalPage){ [Dt\E4
this.totalPage = totalPage; z7K?rgH
} O@$hG8:
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} qJK^i.e
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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 K)14v;@
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个PageUtil,负责对Page对象进行构造: ]MHQ"E?
java代码: &B.r&K&
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/*Created on 2005-4-14*/ s R~&S))
package org.flyware.util.page; %z.G3\s0
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import org.apache.commons.logging.Log; IM#+@vv
import org.apache.commons.logging.LogFactory; DTJ
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/** u)V*o
* @author Joa PQ[TTLG\&
* *[U:'o`67
*/ q+DH2&E'
publicclass PageUtil { fg9sZ%67]\
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privatestaticfinal Log logger = LogFactory.getLog _x
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(PageUtil.class); z=xHk|+'
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/** 'L m
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* Use the origin page to create a new page G'epsD,.bX
* @param page b'&pJ1]]}
* @param totalRecords j NY8)w_
* @return [X
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*/ Cse0!7_T
publicstatic Page createPage(Page page, int _ E%[D(
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totalRecords){ p"JSYF
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return createPage(page.getEveryPage(), P]TT
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page.getCurrentPage(), totalRecords); d.+vjMI
} Y[H_?f=;%
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/** Cam}:'a/`
* the basic page utils not including exception ke%zp-2c
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handler J!H5{7.efN
* @param everyPage \w:u&6,0O
* @param currentPage qYh,No5\;t
* @param totalRecords -3V~YhG
* @return page i`Yf|^;@2>
*/ l=oVC6C
publicstatic Page createPage(int everyPage, int x
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currentPage, int totalRecords){ cU>&E*wD
everyPage = getEveryPage(everyPage); 7mjj%
currentPage = getCurrentPage(currentPage); QA3l:D}u
int beginIndex = getBeginIndex(everyPage, WNx^Rg"
>'
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currentPage); e!8_3BE
int totalPage = getTotalPage(everyPage, R*y[/Aw
BuYDw*.
totalRecords); W(8g3
boolean hasNextPage = hasNextPage(currentPage, {aL$vgYT1
:}-u`K*
totalPage); NWg\{a
boolean hasPrePage = hasPrePage(currentPage); EzyIsp> _
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returnnew Page(hasPrePage, hasNextPage, <8bO1t^*
everyPage, totalPage, ~
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currentPage, CvW((<?
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beginIndex); LJ))
} e.+)0)A-
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privatestaticint getEveryPage(int everyPage){ @}Ixr{t
return everyPage == 0 ? 10 : everyPage; Lwcw%M]
} ;Y'\:
10rGA=x'(
privatestaticint getCurrentPage(int currentPage){ b>z.d-
return currentPage == 0 ? 1 : currentPage; s`J=:>9*
} e^GW[lT
\,EPsQV0?
privatestaticint getBeginIndex(int everyPage, int VqrMi *W6
P~<93
currentPage){ d{hYT\7~1(
return(currentPage - 1) * everyPage; G"[pr%?
} OW}A48X[+
StL[\9~:
privatestaticint getTotalPage(int everyPage, int gB(W`:[
9O Q4\
totalRecords){ Ib\G{$r
int totalPage = 0; kn"x[{d
jq]"6/xxb
if(totalRecords % everyPage == 0) GN9_ZlC
totalPage = totalRecords / everyPage; 9/M!S[N9
else ?>8zU;Aj
totalPage = totalRecords / everyPage + 1 ; #[W[|m
I`TD*D
return totalPage; !S!03|
} EM*OrUe
?GarD3#A
privatestaticboolean hasPrePage(int currentPage){
D.o|($S0
return currentPage == 1 ? false : true; 3R*@m
} |w2AB7EU
}#x3IE6'
privatestaticboolean hasNextPage(int currentPage, 55LF
1hyah.i]Y
int totalPage){ mv.I.EL
return currentPage == totalPage || totalPage == V^z;^mdd
)T5h\ZO`;
0 ? false : true;
;"^9L
} )JQQ4D
{Yk20Zn
mv?H]i`N
} y7-:l u$9
J\ +gd%
0|!<|N<
B9DxV>mr\r
;cn.s,
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 GKhwn&qCKb
\,gZNe&Vv
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 -!>ZATL<B
.b`P!
做法如下: +fQL~0tA
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 25n(&NV
"EYjY->
的信息,和一个结果集List: >Ro n+
oe
java代码: r)]CZ])
|Du13i4].&
&jZ|@K?
/*Created on 2005-6-13*/ Q3%#
o+R>
package com.adt.bo; h;p%EZ
|K;Txe_
import java.util.List; %OW9cqL>l
Yb3f]4EH
import org.flyware.util.page.Page; p}DF$k%`
xO-U]%oq
/** +7<>x-+
* @author Joa ]MLLr'6?
*/ So*Wk "
publicclass Result { @1&;R
Fg\| e%
private Page page; \e8*vos
nYy}''l<
private List content; KbdfSF$
*-AAQ
/** ~1r*/@M[V
* The default constructor [F)/mN
*/ 62l0
Z-
public Result(){ |id79qY7g
super(); N%rL=zE
} XH:gQ 9FD
if[o?6U4t
/** NZC='3Uz
* The constructor using fields N3yB1_
* 1|WpKaMoq
* @param page t-m9n*\j1
* @param content sMS9!{A
*/ Wj j2J8B
public Result(Page page, List content){ sp
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this.page = page; QS [B
this.content = content; "gvw0)
} h @,e`Z
IO!1|JMr6
/** (d'j'U:C
* @return Returns the content. a5}44/%
*/ '<&EPUO
publicList getContent(){ -)OkG#J@
return content; B.mbKntK)R
} aDl,
K;GL
g{W6a2
/** blfE9Oy
* @return Returns the page. &[ u6oAR
*/ X`3vSCn
public Page getPage(){ B>|U-[A
return page; 8gbm "!
} nK h%E-c
[%84L@:h
/** =,d* {m~A
* @param content mfngbFa1
* The content to set. |J<pLz
*/ ~1=.?Ho
public void setContent(List content){ [+'BQ
this.content = content; wyrI8UY
} hD$p;LF
S#h'\/S
/** (~7m"?
* @param page c
BHL,
* The page to set. ,%?; \?b%h
*/ WS1&3mOd
publicvoid setPage(Page page){ prlyaq;4
this.page = page; G/fP(o-Wd
} ! 2Xr~u7a
} rv,NQZ
6MQs \ J6.
1<W4>~,wj
,qe]fo >
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2. 编写业务逻辑接口,并实现它(UserManager, Ig02M_
[%7;f|p?
UserManagerImpl)
{b|3]_-/
java代码: yE.495
)l#%.Z9
:Hzz{'
/*Created on 2005-7-15*/ (:?5 i`
package com.adt.service; t +3
nIyROhZ
import net.sf.hibernate.HibernateException; lrs0^@.+
;]gsJ9FK<
import org.flyware.util.page.Page; :F^$"~(,
DJViy
import com.adt.bo.Result; V8sH{R-
k5aa>6K
/** O t *K+^I
* @author Joa ZDOF
*/ 0'yG1qG
publicinterface UserManager { S,*{q(
NK7H,V}T
public Result listUser(Page page)throws c<=`<!FS[
5)d,G9
HibernateException; sf |oNOz
4_Qa=T8
} y+4?U
s[G|q5n
Wl&
>6./{
t7um
[
{cR_?Y@
java代码: a=J@yK
:DtZ8$I`]C
UF&0&`@
/*Created on 2005-7-15*/ Vs_\ykO
package com.adt.service.impl; cWN d<=Jp
MzEm*`<
import java.util.List; H GO#e
!,cQ'*<W8-
import net.sf.hibernate.HibernateException; /d0Q>v.g
f >mhFy
import org.flyware.util.page.Page; ,f8}q]FTA
import org.flyware.util.page.PageUtil; /S:w&5e
)XLj[6j0
import com.adt.bo.Result; >Z#uFt0<Pm
import com.adt.dao.UserDAO; )-bD2YA{
import com.adt.exception.ObjectNotFoundException; 5h`m]#YEG
import com.adt.service.UserManager; NuC-qG#
%f3c7\=C
/** *Q bM*oH
* @author Joa Pm$F2YrO3
*/ L;/9L[s,
publicclass UserManagerImpl implements UserManager { LP.HS'M~u
Sm$p\ORa
private UserDAO userDAO; h5L=M^z!>
x96qd%l/
/** f{)+-8
* @param userDAO The userDAO to set. +7| [b
*/ /xl4ohL$a
publicvoid setUserDAO(UserDAO userDAO){ .)LZ`Ge3F
this.userDAO = userDAO; 9{_8cpm4
} b;S6'7Jf9
N]B)Fb
/* (non-Javadoc) fNmE,~
* @see com.adt.service.UserManager#listUser @SU8 \:(U
X AQGG>
(org.flyware.util.page.Page) PT3>E5`N u
*/ _Zh2eXWdjM
public Result listUser(Page page)throws 4bP13f
$Mdbto~ <
HibernateException, ObjectNotFoundException { LtC~)R
int totalRecords = userDAO.getUserCount(); R<"2%oY
if(totalRecords == 0) %tT"`%(+
throw new ObjectNotFoundException Z;ZuS[ZA
T>d\%*Q+B
("userNotExist"); wk" l[cH>
page = PageUtil.createPage(page, totalRecords); 3(1]FKZtt
List users = userDAO.getUserByPage(page); b6 $,Xh
returnnew Result(page, users); T!MZ+Ph`F
} d; 9*l!CF
x>}B#
} )VNM/o%Q
lc]V\'e
10mK}HT>4B
}7K@e;YUg
\ jECSV|
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ToV6lS"
BbFa=H.
询,接下来编写UserDAO的代码: Hal7
MP
3. UserDAO 和 UserDAOImpl: Z;#%t.
java代码: yH*hL0mO
m;dm|4L^
%B@!
/*Created on 2005-7-15*/ >^dyQyK
package com.adt.dao; $0_^=DEW
&,J*_F<s2<
import java.util.List; M|d={o9Hp
BWWq4mdb{
import org.flyware.util.page.Page; hw;0t,1
'iJDWxCD
import net.sf.hibernate.HibernateException; =/[ltUKs:a
.Y;b)]@f
/** l09Fn>wa
* @author Joa +#4]o
}6G
*/ _1ew(x2J
publicinterface UserDAO extends BaseDAO { g+/0DO_F3
j.DHqHx
publicList getUserByName(String name)throws T.kyV|
^o YPyk`9
HibernateException; N#4N?BBP"
]nQ+nH
publicint getUserCount()throws HibernateException; I"-dTa
o+NMA
(
publicList getUserByPage(Page page)throws mb&lCd^-
wq UQ"d
HibernateException; k0L] R5W
%Uy%kN_&
} Y(_KizBY
E!zX)|Z<
yMb|I~k
e&0K;yU
?OE#q$ g
java代码: D|l,08n"?
r4u z} jl{
X1oGp+&
/*Created on 2005-7-15*/ n#4Gv|{XMD
package com.adt.dao.impl; I.1D*!tz
Y6A;AmM8
import java.util.List; Z&Ue|Z4Qt
+c--&tBo
import org.flyware.util.page.Page; iwU[6A
=Q-k'= 6\
import net.sf.hibernate.HibernateException; Di> rO038
import net.sf.hibernate.Query; 2:Q(Gl`<l
;\qXbL7
import com.adt.dao.UserDAO; ?n.)&ZIx0
qNxB{0(D
/** VevNG*
* @author Joa Fi4UaJ3K
*/ -p`L%xj\
public class UserDAOImpl extends BaseDAOHibernateImpl A?8\Y{FQ
*t(4 $
implements UserDAO { <C'Z H'p
v`x|]-/M&
/* (non-Javadoc) :'}@Al9=>
* @see com.adt.dao.UserDAO#getUserByName 9C/MRmv`
v>H=,.`0\
(java.lang.String) D<bI2
*/ G(/DtY]
publicList getUserByName(String name)throws aE)by-'
T/l1qcf`wT
HibernateException { Lg4YED9#
String querySentence = "FROM user in class v*z(@<Y
{:bN/zV#
com.adt.po.User WHERE user.name=:name"; 0}]SUe^
Query query = getSession().createQuery
uFG<UF
gzf-)J
(querySentence); ]]2k}A[-I
query.setParameter("name", name); 5dl,co{q
return query.list(); w_Uh
} _fn1)
@pFj9[N
/* (non-Javadoc) vN65T$g7
* @see com.adt.dao.UserDAO#getUserCount() n-J2/j
*/ dz-y}J11
publicint getUserCount()throws HibernateException { t>xd]ti
int count = 0; zXZir7NfM
String querySentence = "SELECT count(*) FROM U%>'"
_Zc4=c,K
user in class com.adt.po.User"; bMm3F%FFq&
Query query = getSession().createQuery 'c %S!$P
F PR`tE
(querySentence); UV AJxqz%}
count = ((Integer)query.iterate().next %d2!\x%bG
BI/&dKM
()).intValue(); I4=Xb^Ux
return count; @0NJ{
}
|yKud
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/* (non-Javadoc) 1/;o
* @see com.adt.dao.UserDAO#getUserByPage vWjnI*6T#
X%}nFgqQ
(org.flyware.util.page.Page) ^zr^ N?a
*/ `VT>M@i/
publicList getUserByPage(Page page)throws |^a;77nE_^
_mJG5(|
HibernateException { ]*N1t>fb
String querySentence = "FROM user in class Udgqkl
}^%xvmQ\]
com.adt.po.User"; taWqSq!
Query query = getSession().createQuery |(%zb\#9
5l{Ts04k%
(querySentence); Kct@87z
query.setFirstResult(page.getBeginIndex()) A m"(+>W21
.setMaxResults(page.getEveryPage()); YcDe@Zuwn
return query.list(); CvDxq:x
} /M=3X||
*[}^[J
x
} "rhYCZ B
.0p^W9
N|usFqCNk^
[}z,J"Un
M4yI`dr6
至此,一个完整的分页程序完成。前台的只需要调用 vFv3'b$;G
]a'99^?\
userManager.listUser(page)即可得到一个Page对象和结果集对象 zjl!9M!
h6:#!Rg
的综合体,而传入的参数page对象则可以由前台传入,如果用 wT,R0~V0
b:W-l?
webwork,甚至可以直接在配置文件中指定。 pUYM}&dX
(?0`d
下面给出一个webwork调用示例: bHE2,;o
java代码: r!
%;R?c
|nUl\WRd\
%aRT>_6"
/*Created on 2005-6-17*/ WXw}^v
package com.adt.action.user; U7h(`b
B1!kn}KlL{
import java.util.List; x;s0j"`Jb
p@
NaD=9
import org.apache.commons.logging.Log; pzZk\-0R
import org.apache.commons.logging.LogFactory; #xh_
import org.flyware.util.page.Page; YJV% a
.a'f|c6
import com.adt.bo.Result; 7gF"=7{-
import com.adt.service.UserService; O+q/4
import com.opensymphony.xwork.Action; ^teq[l$;
6%G-Vs]*2
/** ~`ny@WD9
* @author Joa };L ^w:
*/ _}xd}QW
publicclass ListUser implementsAction{ I:cg}JZ>|
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privatestaticfinal Log logger = LogFactory.getLog S$,'Q^~K
=c.5874A`
(ListUser.class); fWnD\mx?0
QS[L~97m2M
private UserService userService; $'rG-g!f\
w"Y` ]2
private Page page; 4GdX/6C.
58Xzup_"
privateList users; e'%v1-&sP
ia @'%8
/* (t+;O;
* (non-Javadoc) ZBT1Y.qA
* 46@{5)Tq
* @see com.opensymphony.xwork.Action#execute() 'k0[rDFc#3
*/ Pz*_)N}j >
publicString execute()throwsException{ m0n)dje
Result result = userService.listUser(page); YyAJ m^o
page = result.getPage(); "TyJP[/
users = result.getContent(); u$#Wv2| mk
return SUCCESS; q[q?hQ/b
} *iBTI+"]
a8k; (/
/** ~}EMk 3
* @return Returns the page. :}8Z@H!KkY
*/ .IBp\7W!?E
public Page getPage(){ 'rp }G&m
return page; ^&@w$
} >@xrs
&Mq~T_S
/** U4f5xUY0)
* @return Returns the users.
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*/ zi R5:d3
publicList getUsers(){ #6Fez`A
return users; RqEH|EUZ
} ,mhQ"\ +C
R'EUV0KX>Y
/** 7w,FX.=;cv
* @param page VVH.2&`I
* The page to set. Unj.f>U
*/ voP7"Dl[
publicvoid setPage(Page page){ wN1niR'
this.page = page; |F,R&<2
} dI&!e#Y
j`^$#
/** IG)s^bP
* @param users QO;N9ZI
* The users to set. zJP6F.Ov!
*/ @k[R/,#'[t
publicvoid setUsers(List users){ *f&EoUk}F
this.users = users; j
8*ZF
} Ya>oCr}K
Gj"7s8(/K|
/** t!*+8Q!e
* @param userService d\x7Zw>
* The userService to set. BdlVabQyKW
*/ FZ!`B]]le,
publicvoid setUserService(UserService userService){ H
0+dV3
this.userService = userService; O+g3X5f+
} 7VcmVq}X
} =mA: ctu~v
}ci#>
3 "o"fl
'smWLz}
8} =JKR^cK
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, nF6q7
PH"n{lW.T
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 5>BK%`
>2bKSh
么只需要: PV|uPuz
java代码: [2"<W!p
T] 2q?;N
:'#TCDlOb
<?xml version="1.0"?> TXe$<4"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork me[DmiM,
ylt`*|$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- /pF`8$
X]\ \,
1.0.dtd"> :_!8
WB
N<QXmgqx
<xwork> c478P=g=5
Yjx|9_|Xn
<package name="user" extends="webwork- >3z5ww
&u#&@J
interceptors"> pdE3r$C
X]P:CY
<!-- The default interceptor stack name C@th O
xg)v0y~
--> E<yW\
<default-interceptor-ref p.LFVFPT
cA%%IL$R
name="myDefaultWebStack"/> ]`Oo%$Ue
M5xCC!
<action name="listUser" #1>X58I^
@)Ofi j
class="com.adt.action.user.ListUser"> jBegh9KHq
<param fk_o@
G!0
5nsq[Q`
name="page.everyPage">10</param> DGzw8|/(
<result m!<\WN6g
[B+W%g(c-
name="success">/user/user_list.jsp</result> mEG#>Gg$
</action> 4~B>
9<$e>
NH+(?TN
</package> 27;ci:5
J~#;<e{\"
</xwork> D1__n6g[
N^3N[lD{
Fd0%lnui
P*cNh43U
CiB%B`,N
,?L2wl[
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 ki85!k=Q2
V0)fZS@tf
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。 $m42:a mM
\Ym5<];E
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 #5V9oKM
I'|$}/\`
g]*#%Xa
:_O%/k1\@
'nF2aD%A
我写的一个用于分页的类,用了泛型了,hoho vd8{c7g:n
0}b
tXh
java代码: ih7/}
\EVBwE,
`QXErw
package com.intokr.util; gvLf|+m
8 XU1/i7N
import java.util.List; 1Z9qjV%^
>yULC|'F&~
/** Z,=7Tu bR#
* 用于分页的类<br> Y 'ow
* 可以用于传递查询的结果也可以用于传送查询的参数<br> '#k0a,<N
* |`cKD >
* @version 0.01 zzxGAVu
* @author cheng ,lyb!k8
*/ kXf'5p1
public class Paginator<E> { lBaR
privateint count = 0; // 总记录数 \_lod kf
privateint p = 1; // 页编号 Rj4|Q:XG
privateint num = 20; // 每页的记录数 cJrmm2.0kD
privateList<E> results = null; // 结果 -4cXRv]
>(;{C<6|^
/** /oriW;OF
* 结果总数 ;72T|e
*/ ~-I+9F
publicint getCount(){ %HL*c=
return count; E160A5BTx
} \Cii1\R=
}5hqDBK?
publicvoid setCount(int count){ (vTtDKp@
this.count = count; V>b\[(=s
} ?:)]h c
?O8ViB?2
/** 9M:O0) s
* 本结果所在的页码,从1开始 h-%R<[
* nX=$EQiH
* @return Returns the pageNo. f`[R7Q5
*/ BG<q IQd
publicint getP(){ Y*14v~\'
return p; /K(o]J0F
} THS.GvT9[
+ ~>Aj
/** `b^Ru+(dM
* if(p<=0) p=1 CY"/uSB
* & 9<+;*/
* @param p w'm;82V:P-
*/ &sU?Ok6
publicvoid setP(int p){ w'UVKpG+
if(p <= 0) {QwHc5Bf
p = 1; @0F3$
this.p = p; ?nmn1`UT
} PBp^|t]E>
r.BIJt)
/** 0}CGuws
* 每页记录数量 M#8uv-L
*/ ;S>])5<
publicint getNum(){ (Kv#m
3~
return num; [xGf,;Z
} 7eiV{ tYF
%;rHrDP(>
/** *#C+iAF|)'
* if(num<1) num=1 |b)Y#)C;
*/ WUh$^5W
publicvoid setNum(int num){ <UQe.K"
if(num < 1) 1#ft#-g}
num = 1;
&MCbYph,
this.num = num; 1
=M ?GDc
} 7BJzMlJ1Y
QC9eUYe
/** o<|P9#(U"
* 获得总页数 }3OKC2K~
*/ W;,C_
publicint getPageNum(){ s[w6FXt
return(count - 1) / num + 1; ;oc&Hb
} "\3B^ e,
"t~
/** ;oy-#p>N%
* 获得本页的开始编号,为 (p-1)*num+1 ])nPPf
*/ Y9&,t\ q
publicint getStart(){ rl#p".4q
return(p - 1) * num + 1; BBtzs^C|
} 3G(miP6
]{ntt}3G,
/** 50o~ P!Lz|
* @return Returns the results. <psZQdH
*/ .n~M(59
publicList<E> getResults(){ AD|2qM))
return results; ~x]jB
} 70eb]\%
<c2'0I >
public void setResults(List<E> results){ Z\k&gio5C^
this.results = results; \Hn>oonph
} \Ol kM<
_tYx~J2.Q
public String toString(){ ;N0~;I
StringBuilder buff = new StringBuilder yge,8i)c
{o.FlX
(); U
15H2-`
buff.append("{"); 4#:W.]U8
buff.append("count:").append(count); ;{U@qQD7
buff.append(",p:").append(p); ]3X@_NYj
buff.append(",nump:").append(num); oyYR-4m\
buff.append(",results:").append R5X.^u
BEre*J
(results); x3o]U)^
buff.append("}"); d%V*|0c)
return buff.toString(); tF{D= ;G
} [E/\#4b
V;,{}
} qLB)XnQ
Ht&:-F+dm
osX8eX]\