Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4sQm"XgE
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fb `x1Q
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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 "kFH*I+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 TBPu&+3
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。 7<e}5nA/
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分页支持类: J(d+EjC
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java代码: hDB(y4/
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package com.javaeye.common.util; .uauSx/#4
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import java.util.List; uCB9;+ Hjw
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publicclass PaginationSupport { q C cLd7`$
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publicfinalstaticint PAGESIZE = 30; qsoq1u,?
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privateint pageSize = PAGESIZE; N7lg6$s Aj
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privateList items; H%Vf$1/TF
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privateint totalCount; X[dfms;H
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privateint[] indexes = newint[0]; o c]
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privateint startIndex = 0; _ncBq;j{
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public PaginationSupport(List items, int VNT?
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totalCount){ ])F+ C/Px1
setPageSize(PAGESIZE); B7'#8heDh
setTotalCount(totalCount); $}tF66d
setItems(items); kEC^_sO"
setStartIndex(0); jnOnV1I"
} Lw[=pe0e
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public PaginationSupport(List items, int Cscu
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totalCount, int startIndex){ v.8kGF
setPageSize(PAGESIZE);
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setTotalCount(totalCount); ~HGSA(
setItems(items); SF;\*]["f
setStartIndex(startIndex); l VD{Y`)
} P-2DBNB7
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public PaginationSupport(List items, int 0`7yPq*
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totalCount, int pageSize, int startIndex){ ,i}EGW,9q
setPageSize(pageSize); M| Gl&
setTotalCount(totalCount); hR|xUp
setItems(items); WZ6{9/%:
setStartIndex(startIndex); SS%Bde&<{
} ]N]Fb3
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publicList getItems(){ "1Hn?4nz5
return items; kJuG haO
} dpq(=s`s
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publicvoid setItems(List items){ B/a`5&G]
this.items = items; Xykoq"dbb
} ej_u):G*
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publicint getPageSize(){ |g}r
return pageSize; AFL'Ox]0
} ]>[TF'pIAx
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publicvoid setPageSize(int pageSize){ vS~tr sI
this.pageSize = pageSize; LWqKSNE;
} AcnY6:3Y|
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publicint getTotalCount(){ Rq+7&%dy
return totalCount; BV@q@C
} w=_^n]`R
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publicvoid setTotalCount(int totalCount){ `+< ^Svou
if(totalCount > 0){ >2>/
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this.totalCount = totalCount; HN`qMGW^
int count = totalCount / Co nik`
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pageSize; 08jk~$%
if(totalCount % pageSize > 0) u
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count++; g$e|y#Ic$
indexes = newint[count]; }U'9 d#N
for(int i = 0; i < count; i++){ 9a=:e=q3#
indexes = pageSize * 7W SP0Xyz
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i; xF3FY0U[
} L"9Z{o7
}else{ 3s%DF,
this.totalCount = 0; ef7 U7
} U5j4iz'
} FYFlh^}
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publicint[] getIndexes(){ FXT^r3
return indexes; +p>h` fc
} q)?!]|pZ
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publicvoid setIndexes(int[] indexes){ [g}#R#Y)
this.indexes = indexes; vde!k_,wZ
} `-U?{U}H
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publicint getStartIndex(){ {_(R?V]w,
return startIndex; tH0x|
} ?QFxds
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publicvoid setStartIndex(int startIndex){ j<!dpt
if(totalCount <= 0) fCNQUK{Gs5
this.startIndex = 0; B2$cY;LH
elseif(startIndex >= totalCount) aKW-(5<JW
this.startIndex = indexes pe,y'w{
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[indexes.length - 1]; XgVhb<l_
elseif(startIndex < 0) 1l)j(,Zd*
this.startIndex = 0; AfO.D?4x
else{ ^zT=qBl
this.startIndex = indexes <f:(nGj
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[startIndex / pageSize]; W Pr:d
} )d3C1Pd>
} 5#|&&$)
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publicint getNextIndex(){ _VgFuU$h
int nextIndex = getStartIndex() + ,f)+|?wz
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pageSize; 8*?H~q~
if(nextIndex >= totalCount) v~AshmP
return getStartIndex(); 8VU(+%X
else $$p +~X
return nextIndex; ktfxb<%
} C%<Dq0j
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publicint getPreviousIndex(){ *uK!w(;2
int previousIndex = getStartIndex() - }+`,AC`RM
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pageSize; x{!+4W;S
if(previousIndex < 0) #sF#<nHZ
return0; .#tA .%
else K~-V([tWg
return previousIndex; )!VJ\
} $SA
@ "
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} KMfIp:~
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抽象业务类 m7A3i<6p
java代码: \N|}V.r
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/** )~$ejS
* Created on 2005-7-12 @HI@PZ>
*/ &uaSp,L
package com.javaeye.common.business; l(3PxbT
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import java.io.Serializable; ".AW
import java.util.List; V1nqEdhk
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import org.hibernate.Criteria; RJ 4=AA|
import org.hibernate.HibernateException; A$\/D2S7!
import org.hibernate.Session; e
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import org.hibernate.criterion.DetachedCriteria; 1=>b\"P#E
import org.hibernate.criterion.Projections; k'F*uS
import DN*M-o9
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org.springframework.orm.hibernate3.HibernateCallback; oWDn_GnG`h
import `T%nGV l>\
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org.springframework.orm.hibernate3.support.HibernateDaoS GM^H
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upport; .;bU["fn)
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import com.javaeye.common.util.PaginationSupport; =b )!l9TX
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public abstract class AbstractManager extends :*l\j"fX5
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HibernateDaoSupport { ?a,`{1m0\
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privateboolean cacheQueries = false; %qrUP\rn
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privateString queryCacheRegion; ]-heG'y]{
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publicvoid setCacheQueries(boolean w9x5 IRW k
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cacheQueries){ ?u{Mz9:?HT
this.cacheQueries = cacheQueries; s"tH?m
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} S?'L%%Vo
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publicvoid setQueryCacheRegion(String HmsXV_B8[Y
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queryCacheRegion){ V^;lg[:
this.queryCacheRegion = 'wBOnGi6
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queryCacheRegion; 7<8'7<X
} b9b`%9/L
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publicvoid save(finalObject entity){ 7Y4D9pw
getHibernateTemplate().save(entity); Csgby(D*O
} ]P^3uXi
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publicvoid persist(finalObject entity){ Vd)
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getHibernateTemplate().save(entity); m60hTJ?N)
} ^6CPC@B1
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publicvoid update(finalObject entity){ h^{aG ])
getHibernateTemplate().update(entity); r24
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} op&j4R
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); +).=}.k
} g'-hSV/@}@
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publicObject load(finalClass entity, S =sL:FC
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finalSerializable id){
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return getHibernateTemplate().load .b2%n;_>.
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(entity, id); bg|=)sw4
} [H`5mY@
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publicObject get(finalClass entity, ]jmZ5h#[
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finalSerializable id){ PDh!B_+
return getHibernateTemplate().get W3MH8z
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(entity, id); gp{Z]{io
} `V[ hE
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publicList findAll(finalClass entity){ Tkh?F5l
return getHibernateTemplate().find("from kRiZ6mn
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" + entity.getName()); 0+rBGk
} gF~
}
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publicList findByNamedQuery(finalString fAT
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namedQuery){ ~~,#<g[
return getHibernateTemplate g3(?!f
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().findByNamedQuery(namedQuery); @Y6~;(p
} 'sjks sy.3
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publicList findByNamedQuery(finalString query, BQ!_i*14+
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finalObject parameter){ 4?x$O{D5?{
return getHibernateTemplate &y2DI"Ff
x Sv@K5"8!
().findByNamedQuery(query, parameter); MWn[]'TpH
} =vKSvQP@)
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publicList findByNamedQuery(finalString query, `9G1Bd8k
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finalObject[] parameters){ # 9ZO1\
return getHibernateTemplate )x&>Cf<,
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().findByNamedQuery(query, parameters); B o[aiT
} #X<s_.7DJ
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publicList find(finalString query){ ZV:0:k.x
return getHibernateTemplate().find g\?7M1~
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(query); Z&y9m@
} /}-LaiS
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publicList find(finalString query, finalObject `H|#l\
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parameter){ |w`Q$ c
return getHibernateTemplate().find tp +H]H3
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(query, parameter); x):h|/B
} |H-zm&h>'
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public PaginationSupport findPageByCriteria &qeMYYY
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(final DetachedCriteria detachedCriteria){ 4p/d>DTiM
return findPageByCriteria 4ko(bW#jL
=a./HCF
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7Dx<Sr!
} C5'#0}6i
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public PaginationSupport findPageByCriteria CC`Y r
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(final DetachedCriteria detachedCriteria, finalint cpBTi
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startIndex){ l0{R`G,
return findPageByCriteria j}@n`[V1
ns !Mqcm
(detachedCriteria, PaginationSupport.PAGESIZE, 4VfZw\^
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startIndex); \@:mq]Y
} 3R$*G8v
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public PaginationSupport findPageByCriteria {vAv ;m
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(final DetachedCriteria detachedCriteria, finalint dht*1i3v
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pageSize, ioS(;2F
finalint startIndex){ $#F7C[2N
return(PaginationSupport) 7
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getHibernateTemplate().execute(new HibernateCallback(){ XSz)$9~hk
publicObject doInHibernate ~i/K7qZ
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(Session session)throws HibernateException { 0:4w@"Q
Criteria criteria = qEV>$>}
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detachedCriteria.getExecutableCriteria(session); G^/8lIj
int totalCount = rnTjw
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((Integer) criteria.setProjection(Projections.rowCount \ POQeZ
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()).uniqueResult()).intValue(); 6'1m3<G_
criteria.setProjection nf9NJ_8}4H
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(null); V'&`JZK6
List items = ww$Ec
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criteria.setFirstResult(startIndex).setMaxResults _G=k^f_
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(pageSize).list(); u~q6?*5
PaginationSupport ps = jz72~+)T
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new PaginationSupport(items, totalCount, pageSize, t bEJyA
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startIndex); rc+}KO
return ps; -yP_S~\n
} ._IBO; *@
}, true); hTVA^j(w
} r;cILS|Xr
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public List findAllByCriteria(final VgyY7INx9
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DetachedCriteria detachedCriteria){ xl4 A<
return(List) getHibernateTemplate Pmj%QhOYE
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().execute(new HibernateCallback(){ -{rUE +
publicObject doInHibernate D>efr8Qd@
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(Session session)throws HibernateException { yRv4,{B}X>
Criteria criteria = G2BB]] m3
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detachedCriteria.getExecutableCriteria(session); p?XVO#
return criteria.list(); (N
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} c}r"O8M
}, true); ;o-c.-!F
} o-_H+p6a
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public int getCountByCriteria(final *$yU|,
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DetachedCriteria detachedCriteria){ @ UCr`>
Integer count = (Integer) ;fGh]i
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getHibernateTemplate().execute(new HibernateCallback(){ Vx*O^cM
publicObject doInHibernate ].r~?9'/
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(Session session)throws HibernateException { %29lDd(<
Criteria criteria = B
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detachedCriteria.getExecutableCriteria(session); 0S71&I$u]
return G24Ov&H
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criteria.setProjection(Projections.rowCount )LDBvpJyQ
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()).uniqueResult(); JsD|igqF-
} vA&MJD{
}, true); Jwt_d}ns
return count.intValue(); j9^V)\6)
} N83c+vs%c
} hxe X6
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用户在web层构造查询条件detachedCriteria,和可选的 xh|<`>5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 33z^Q`MTC
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PaginationSupport的实例ps。 }NpN<C+
5-?*Boi>i
ps.getItems()得到已分页好的结果集 My<.^~
ps.getIndexes()得到分页索引的数组 2D)B%nM[
ps.getTotalCount()得到总结果数 'B yB1NL
ps.getStartIndex()当前分页索引 ;(r,;S_`0
ps.getNextIndex()下一页索引 5u=>~yK+
ps.getPreviousIndex()上一页索引 X([p0W
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8 @A}.:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 b>]k=zd
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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 x|`BF%e/v
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一下代码重构了。 _Nacqa
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我把原本我的做法也提供出来供大家讨论吧: >0E3Em<(}l
Nbb2wr9A
首先,为了实现分页查询,我封装了一个Page类: 8@,8j!$8G
java代码: s((c@)M
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/*Created on 2005-4-14*/ ,{2= nb[
package org.flyware.util.page; w8}jmpnI
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/** |'qvq/#^
* @author Joa /(8"9Sfm
* :Lu 9w0>f
*/ #5%ipWPHb
publicclass Page { +$$5Cv5#<&
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/** imply if the page has previous page */ $O_{cSKg7
privateboolean hasPrePage; ftxy]NLF
9";qR,
/** imply if the page has next page */ 21[=xboU
privateboolean hasNextPage; 7sq15oL
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/** the number of every page */ @Y !Jm
privateint everyPage; ek1<9"y
Q6;bORN
/** the total page number */ =$SvKzN
privateint totalPage; o1R:1!"2
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/** the number of current page */ MSE0z!t
privateint currentPage; {t!Pv2y<
S S fNI>
/** the begin index of the records by the current d<RJH
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query */ 9AJ"C7
privateint beginIndex; K57u87=*X?
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/** The default constructor */ apjoIO-<
public Page(){ 4JRQ=T|P7I
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} 9Ed=`c
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/** construct the page by everyPage SP"t2LTP
* @param everyPage *Hz]<b?
* */ \aN7[>R.Q
public Page(int everyPage){ *alifdp
this.everyPage = everyPage; {Z1KU8tp
} {q! :t0X.Y
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/** The whole constructor */ Rj3ad 3z'E
public Page(boolean hasPrePage, boolean hasNextPage, KAgxIz!^-1
|$g} &P8;
*!pn6OJ"Q}
int everyPage, int totalPage, qOv`&%txW
int currentPage, int beginIndex){ >XxHp
this.hasPrePage = hasPrePage; @r=,:
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this.hasNextPage = hasNextPage; KM?w{ ~9
this.everyPage = everyPage; -S#jOr
this.totalPage = totalPage; 3_8W5J3I
this.currentPage = currentPage; Qb|@DMq%
this.beginIndex = beginIndex; .bUj
} YJ|U|[
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/** rl,i,1t
* @return _nM 7SK
* Returns the beginIndex. Hk'R!X
*/ /U})mdFm
publicint getBeginIndex(){ <G'M/IR a
return beginIndex; md `=2l
} zkquXzlgB
>qBJK)LHOv
/** -]t>'Q?
* @param beginIndex 9/_~YY=/h
* The beginIndex to set. &?}A/(#
*/ ~C>clkZ
publicvoid setBeginIndex(int beginIndex){ rv`GOta*
this.beginIndex = beginIndex; 1@i/N
} Nt\0) &b
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/** "T*1C=
* @return sX-@
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* Returns the currentPage. Shv$"x:W
*/ OZA^L;#>
publicint getCurrentPage(){ V"B/4v>
return currentPage; )2Bb,p<Wr
} #lO ^PK
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/** `Tei
* @param currentPage C80< L5\
* The currentPage to set. b
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*/ BwrX.!M
publicvoid setCurrentPage(int currentPage){ n5z|@I`S_
this.currentPage = currentPage; M2\c0^R
} I E{:{b\
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/** 4)8e0L*[B?
* @return HYL['B?Wid
* Returns the everyPage. 8/T,{J\
*/ SSq4KFO1
publicint getEveryPage(){ T0~~0G)k
return everyPage; @1xIph<z
} GaV} @Q
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/** |>OBpb
* @param everyPage x4(8
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* The everyPage to set. t fD7!N{
*/ v^)B[e!
publicvoid setEveryPage(int everyPage){ UB+7]S
this.everyPage = everyPage; Kr[oP3
} s4QCun~m
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/** {pA&Q{ ^
* @return mi.,Z`]o
* Returns the hasNextPage. kBxEp/y
*/ W 1u!&:O
publicboolean getHasNextPage(){ v*&jA8D
return hasNextPage; Y`#6MhFT7
} pmOUl 8y4
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/** /]U;7)
* @param hasNextPage (G/(w%#7_
* The hasNextPage to set. R>]7l!3^1
*/ z~==7:Os
publicvoid setHasNextPage(boolean hasNextPage){ D/JSIDd
this.hasNextPage = hasNextPage; }+Q4s]
} b^&azUkMN
bWSc&/9y
/** 9 )!}
* @return b(CO7/e>
* Returns the hasPrePage. [$pb
*/ jD%|@ux
publicboolean getHasPrePage(){ ~)n[Vf
return hasPrePage; <*WGvCh%w
} 3fA+{Y8S
g cB
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/** ^b|I^TN0
* @param hasPrePage =<7z
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* The hasPrePage to set. |a
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*/ K&RIF]0#G
publicvoid setHasPrePage(boolean hasPrePage){ 4HR36=E6
this.hasPrePage = hasPrePage; D.Cn`O}
} jm@,Ihz=wI
];"40 /X
/** o"FR%%
* @return Returns the totalPage. e!o\AB%d
* '7/F]S0K
*/ N{~P}Sw
publicint getTotalPage(){ q
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return totalPage; wy8Q=X:vP
} NbTaI{r
V.*y_=i8t
/** w%plK6:6
* @param totalPage Tl'wA^~H
* The totalPage to set. r>7+&s*yk
*/ $(+xhn(O
publicvoid setTotalPage(int totalPage){ K0>+-p oL
this.totalPage = totalPage; 8aIqc
} %P M#gnt@
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} -*Rf [|Z
KO~KaN
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F\^8k /0
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 LMx/0
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个PageUtil,负责对Page对象进行构造: S89j:KRXH%
java代码: 3 o$zT9j
+RJKJ:W
WJu(,zM?G
/*Created on 2005-4-14*/ >j3':>\U
package org.flyware.util.page; 7}y@VO6]
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import org.apache.commons.logging.Log; K;WQV,
import org.apache.commons.logging.LogFactory; ok0ZI>=,
L\UGC%]9
/** <#4""FO*
* @author Joa -CuuO=h
* 8)=(eI$
*/ </D.}ia
publicclass PageUtil { Maq`Or|4
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privatestaticfinal Log logger = LogFactory.getLog Q{?\qCrrYl
dNNXMQ0"
(PageUtil.class); m;\nMdn
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/** =}kISh
* Use the origin page to create a new page mXyN{`q=
* @param page U;4i&=.!
* @param totalRecords "uT2 DY[
* @return /RMtCa~
*/ 4v |i\V>M
publicstatic Page createPage(Page page, int D!!
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totalRecords){ ib#rT{e
return createPage(page.getEveryPage(), @'):rFr@F
3<"j/9;K'
page.getCurrentPage(), totalRecords); @&`^#pok
} OylUuYy~j
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/** ZS4dW_*[
* the basic page utils not including exception yo->mD
*$|f9jVh
handler ^|p D(v
* @param everyPage |9\i+)C
* @param currentPage k ,ldi
* @param totalRecords G+Z ,ic
* @return page >r7PK45.K
*/ ?d%{-
publicstatic Page createPage(int everyPage, int =X^a
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currentPage, int totalRecords){ r7g@(K
everyPage = getEveryPage(everyPage); "yh2+97l
currentPage = getCurrentPage(currentPage); /g!ZU2&l
int beginIndex = getBeginIndex(everyPage, Hv/5)
fs;\_E[)
currentPage); )Z1&`rv
int totalPage = getTotalPage(everyPage, B>>_t2IU
`|>]P"9yp
totalRecords); =pi,]m
boolean hasNextPage = hasNextPage(currentPage, NfPWcK[
MD;Z UAX<
totalPage); *EvW: <
boolean hasPrePage = hasPrePage(currentPage); )mf|3/o
l7jen=(Zb;
returnnew Page(hasPrePage, hasNextPage, j0~am,yZ
everyPage, totalPage, jT$J~MpHh
currentPage, 6xtgnl#T
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beginIndex); hZ452W
} mj e9i
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privatestaticint getEveryPage(int everyPage){ <=GZm}/]N
return everyPage == 0 ? 10 : everyPage; E;s_=j1f
} 6'kQ(r>
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privatestaticint getCurrentPage(int currentPage){ @O'NJh{D`
return currentPage == 0 ? 1 : currentPage; }Vob)r{R@
} dWiNe!oY2
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privatestaticint getBeginIndex(int everyPage, int hBnUpYec
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currentPage){ =E]tEi
return(currentPage - 1) * everyPage; $;G<!]& s
} He'VqUw_
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privatestaticint getTotalPage(int everyPage, int O2ktqAWx@
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totalRecords){ B
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int totalPage = 0; y[85eM
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if(totalRecords % everyPage == 0) B-w`mcqp$
totalPage = totalRecords / everyPage; u9KT_`
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else `r-Jy{!y4
totalPage = totalRecords / everyPage + 1 ; vJGH8$%;,
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return totalPage; 8g!79q\c4
} Qx,#Hj
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privatestaticboolean hasPrePage(int currentPage){ z"yW):X
return currentPage == 1 ? false : true; ,)*[Xa_n
} )uOtQ0
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privatestaticboolean hasNextPage(int currentPage, 1c#\CO1l
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int totalPage){ \RR`
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return currentPage == totalPage || totalPage == BWxJ1ENM
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0 ? false : true; $Ugc:L<h+
} #~/9cVm$
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} X41Qkf{
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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。 )@I] Rk?
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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 }JST(d&
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做法如下: w (RRu~J
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 TO5y.M|7
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的信息,和一个结果集List: \8<[P(!3
java代码: 2HBey
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/*Created on 2005-6-13*/ :Ob^b3<t
package com.adt.bo; =>c0NT
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import java.util.List; `3ha~+Goo!
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import org.flyware.util.page.Page; *&Iv Eu
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/** $mKExW
* @author Joa ]!^wB 3j
*/ "@^<~bw
publicclass Result { dF 6od
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private Page page; 7J5jf231
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private List content; G)[gLD{g?
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/** tzd!r7
* The default constructor Q.eD:@%iE
*/ 8(Ptse
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public Result(){ >gL&a#<S
super(); >f Hu
} 6l2O>V
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/** Wd!Z`,R
* The constructor using fields $PRd'YdL/
* *a\x!c"
* @param page q:M'|5P
* @param content D`[@7$t
*/ l$j~p=S$F
public Result(Page page, List content){ X6Z/xb@
this.page = page; V >eG\
this.content = content; b|k^
} #W/Ch"Kv
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/** vv2[t
* @return Returns the content. _8y4U[L
*/ .p=J_%K}0x
publicList getContent(){ LqI&1$#
return content; N-2_kjb!
} _ ~yd
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/** |ITCw$T
* @return Returns the page. h {J io>
*/ cy?#LS
public Page getPage(){ zBq&/?
return page; ?MSwr_eZH
} LU8[$.P
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/** 0S>L0qp
* @param content wsQuJrG
* The content to set. l44QB8
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*/ GSSmlJ`
public void setContent(List content){ TYR \K
this.content = content; 1'p=yHw
} ep},~tPZn
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/** B>cT<B
* @param page `5(F'o
* The page to set. GNuIcy
*/ S?JGg.)
publicvoid setPage(Page page){ N8kNi4$mp=
this.page = page; YZ:C9:S6X
} 9* 3;v;F
} RS&BS;
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2. 编写业务逻辑接口,并实现它(UserManager, Fkpaou
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UserManagerImpl) | X#!5u
java代码: mqsAYzG
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/*Created on 2005-7-15*/ e9/Mjq\
package com.adt.service; :/$_eg0A
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import net.sf.hibernate.HibernateException; GNrRc3dr$
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import org.flyware.util.page.Page; Pe\Obd8d
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import com.adt.bo.Result; v?,@e5GZ
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/** Tjv'S
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* @author Joa aqQ+A:g
*/ .$y'>O*$G
publicinterface UserManager { Eld[z{n"
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public Result listUser(Page page)throws }f}? |&q
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HibernateException; [~\]<;;\
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} PXtF#,roP
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