Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 t
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Z=>#|pW,)
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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 el^WBC3
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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 2k"!o~s^
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分页支持类: nL&[R}@W
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java代码: _tpqo>
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package com.javaeye.common.util; OG}m+K&<
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import java.util.List; %P-z3 0FHp
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publicclass PaginationSupport { %v 1NDhaXz
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publicfinalstaticint PAGESIZE = 30; g:CMIe4
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privateint pageSize = PAGESIZE; K,L
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privateList items; UqaV9
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privateint totalCount; a 9f%p
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privateint[] indexes = newint[0]; Q{+N{/tF
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privateint startIndex = 0; '"14(BvW
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public PaginationSupport(List items, int b)Dzau
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totalCount){ dUL3UY3
setPageSize(PAGESIZE); DZ~qk+,I
setTotalCount(totalCount); \1b! I)T9
setItems(items); LHJjPf)F
setStartIndex(0); Z 361ko}
} Ud[Zv?tA:
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public PaginationSupport(List items, int BX=YS)
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totalCount, int startIndex){ 6+Wkcrh
setPageSize(PAGESIZE); ]Sgc42hk
setTotalCount(totalCount); ;;g'C*_
setItems(items); j^'op|l
setStartIndex(startIndex); /K<.$B8
} UuvI?D
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public PaginationSupport(List items, int 9>na3ISh
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totalCount, int pageSize, int startIndex){ (r+#}z}
setPageSize(pageSize); ?Wz
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setTotalCount(totalCount); |VRzIA4M\
setItems(items); O4i5fVy{
setStartIndex(startIndex); }+Ne)B E
} jLu`DKB
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publicList getItems(){ W4~:3Sk
return items; Ot#O];3
} iI(7{$y
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publicvoid setItems(List items){ dy%#E2f
this.items = items; ypK1
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} ApxGrCu
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publicint getPageSize(){ s9'lw'
return pageSize; }+4^ZbX+:
} <Fa]k'<^)
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publicvoid setPageSize(int pageSize){ E
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this.pageSize = pageSize; LCMCpEtY*K
} x{';0MkUV
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publicint getTotalCount(){ Q(\U'|%J
return totalCount; 8NRc+@f|m
} <p74U( V
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publicvoid setTotalCount(int totalCount){ xF4>G0
if(totalCount > 0){ lSzLR~=Au
this.totalCount = totalCount; `Z:5 E
int count = totalCount / <cn{S`
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pageSize; @GpM4>:
if(totalCount % pageSize > 0) dE[nPtstb
count++; &eHhj9
indexes = newint[count]; |_^A$Hv
for(int i = 0; i < count; i++){ I*Q^$YnM
indexes = pageSize * N5%zbfKM
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i; ~;*SW[4
} SXW8p>1Jw
}else{ (!@
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this.totalCount = 0; mu?6Phj
} t<|S7EqIL
} &(]@L\A
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publicint[] getIndexes(){ z!r-g(^G
return indexes; g5
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} z"@yE*6
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publicvoid setIndexes(int[] indexes){ jeM/8~^4-
this.indexes = indexes; [8o!X)
} t)*MLg<C
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publicint getStartIndex(){ nf7l}^/UE
return startIndex; lStYfO:<'v
} JQhw>H9&
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publicvoid setStartIndex(int startIndex){ Xo{|m[,
if(totalCount <= 0) w,t>M_(N
this.startIndex = 0; =&J7
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elseif(startIndex >= totalCount) >+ZG{'!j
this.startIndex = indexes Gqz<;y
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[indexes.length - 1]; #=G[~m\
elseif(startIndex < 0) .UUY9@
this.startIndex = 0; +x3T^G
else{ Sj$XRkbj:
this.startIndex = indexes Uo!#p'<w)p
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[startIndex / pageSize]; FOFZ/q
} /NH9$u.g
} $&@L[[xl
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publicint getNextIndex(){ 4|9c+^%^
int nextIndex = getStartIndex() + .%D9leiRe
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pageSize; e*7nq~ B5
if(nextIndex >= totalCount) wIv_Z^%V
return getStartIndex(); Tq r]5
else r
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return nextIndex; gRk%ObJGqm
} |-W7n'n
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publicint getPreviousIndex(){ [q/tKdo@
int previousIndex = getStartIndex() - \Qh{uk[
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pageSize; {g:I5
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if(previousIndex < 0) ndIf1}
return0; 3 9|4)1e
else bvf}r
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return previousIndex; )jh4HMvmC
} &:i|;^^2
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} W3XVr&
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抽象业务类 8Rgvb3u
java代码: (o!v,=# 6{
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/** {R2gz]v4
* Created on 2005-7-12 u*I=.
*/ TV~<1vj
package com.javaeye.common.business; MT8BP)C
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import java.io.Serializable; [Ch)6p
import java.util.List; [7Yfv
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import org.hibernate.Criteria; CnJrJ>l
import org.hibernate.HibernateException; y5d=r]_S:
import org.hibernate.Session; mG?g
import org.hibernate.criterion.DetachedCriteria; Mpfdl65
import org.hibernate.criterion.Projections; ^^u{W|'CaH
import hPs7mnSW
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org.springframework.orm.hibernate3.HibernateCallback; 03WLVP@
import woctnT%"Q/
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org.springframework.orm.hibernate3.support.HibernateDaoS K0|8h!WF+
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upport; x<m{B@3T
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import com.javaeye.common.util.PaginationSupport; p[Pa(a,B7
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public abstract class AbstractManager extends }klET
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HibernateDaoSupport { k3[%pS
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privateboolean cacheQueries = false; W6_~.m"b
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privateString queryCacheRegion; XYJ7k7zc+Y
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publicvoid setCacheQueries(boolean C%$:Oq
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cacheQueries){ 1:7 uS.
this.cacheQueries = cacheQueries; cs]N%M^s
} .AIlv^:|U
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publicvoid setQueryCacheRegion(String O]"3o,/]G
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queryCacheRegion){ q5jLK)
this.queryCacheRegion = cR/-FR
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queryCacheRegion; wT;3>%Mtr
} DAZzc :1Aj
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publicvoid save(finalObject entity){ %\5wHT+)
getHibernateTemplate().save(entity); 3#{{+5G
} 83 O+`f
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publicvoid persist(finalObject entity){ c-|~ABtEpX
getHibernateTemplate().save(entity); huMNt6P[
} fOE8{O^W
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publicvoid update(finalObject entity){ So&an !
getHibernateTemplate().update(entity); zh5$$*\
} J^}w,r*=
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publicvoid delete(finalObject entity){ K4]42#
getHibernateTemplate().delete(entity); 8<,b5
} PNm WZW*
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publicObject load(finalClass entity, H3$~S '
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finalSerializable id){ ]2^tV.^S^
return getHibernateTemplate().load \E9Hk{V:6
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(entity, id); c6IFt4)g
} h5+qP"n!?q
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publicObject get(finalClass entity, >d.o1<
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finalSerializable id){ 4dkU;Ob
return getHibernateTemplate().get aBo8?VV]8
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(entity, id); YeN /J.R
} Ix+===6
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publicList findAll(finalClass entity){ G k'j<a
return getHibernateTemplate().find("from eY3l^Su1
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" + entity.getName()); 1!u}~E_
} ',?9\xEB
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publicList findByNamedQuery(finalString e-$U .cx
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namedQuery){ J.
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return getHibernateTemplate :K%{?y
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().findByNamedQuery(namedQuery); 2C9wOO
} tBDaFB
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publicList findByNamedQuery(finalString query, czMu<@c [
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finalObject parameter){ )Fc`rY
return getHibernateTemplate ]Lc:M'V#
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().findByNamedQuery(query, parameter); b;wf7~a*
} "AN2K
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publicList findByNamedQuery(finalString query, | aH;@V
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finalObject[] parameters){ ]Y#$!fIx
return getHibernateTemplate Ri$wt.b
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().findByNamedQuery(query, parameters); BMw_F)hTO
} sE*A,z?
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publicList find(finalString query){ PJC[#>}
return getHibernateTemplate().find !Vtt.j &4
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(query); f/spJ<B).4
} [Z2:3*5r.
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publicList find(finalString query, finalObject t;P%&:"@M
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parameter){ 4"$K66yk@
return getHibernateTemplate().find >KjyxJ7
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(query, parameter); w7b?ve3-
} \Mk;Y
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public PaginationSupport findPageByCriteria \3P.G S{l
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria EleK*l
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 1:-^*
} __U;fH{c
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public PaginationSupport findPageByCriteria TGnyN'P|
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(final DetachedCriteria detachedCriteria, finalint f
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startIndex){ =Qt08,.bW
return findPageByCriteria &5&C
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(detachedCriteria, PaginationSupport.PAGESIZE, '}a[9v76
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startIndex); ny:c&XS
} Lp\89tB>
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public PaginationSupport findPageByCriteria fMjn8.
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(final DetachedCriteria detachedCriteria, finalint zx7*Bnu0
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pageSize, TGxspmY6
finalint startIndex){ ^H'zS3S
return(PaginationSupport) Ro+/=*ql~
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getHibernateTemplate().execute(new HibernateCallback(){ sY?pp
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publicObject doInHibernate WeGT}
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(Session session)throws HibernateException { mk JS_6
Criteria criteria = &&e{ 9{R
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detachedCriteria.getExecutableCriteria(session); 9wLV\>i[k
int totalCount = ~__]E53F
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((Integer) criteria.setProjection(Projections.rowCount tN|sHgs
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()).uniqueResult()).intValue(); Gy36{*
criteria.setProjection t0Q/vp*/
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(null); ^6v ob
List items = ^ri?eKy.-g
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criteria.setFirstResult(startIndex).setMaxResults
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9WQC\/w
(pageSize).list(); E?|"?R,,,
PaginationSupport ps = '>(R'g42n
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new PaginationSupport(items, totalCount, pageSize, V.;,1%
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startIndex); >V:g'[b
return ps; (80#{4kl
} -d\O{{%>.z
}, true); _5Q?]-M
} >8;Co]::kx
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public List findAllByCriteria(final F,#)8>O
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DetachedCriteria detachedCriteria){ 8:,E=swe
return(List) getHibernateTemplate -A}*Aa'\
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().execute(new HibernateCallback(){ uV<I!jyI
publicObject doInHibernate 2U,O
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(Session session)throws HibernateException { <Gzy*1Q&
Criteria criteria = m`UNdFS
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detachedCriteria.getExecutableCriteria(session); )AOD~T4s7
return criteria.list(); !Y_"q^5GG'
} iK%<0m
}, true); tx;DMxN!W
} Q[i/]
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public int getCountByCriteria(final JsOPI]
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DetachedCriteria detachedCriteria){ oo7&.HWf
Integer count = (Integer) XJnDx 09h
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getHibernateTemplate().execute(new HibernateCallback(){ o[*</A
}
publicObject doInHibernate *zX*k7LnV
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(Session session)throws HibernateException { '>>
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Criteria criteria = %7BVJJp2
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detachedCriteria.getExecutableCriteria(session); vTYI
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return yv4ki5u`
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criteria.setProjection(Projections.rowCount ]B0>r^
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()).uniqueResult(); j[YzBXd
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} Kg&{
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}, true); y|b|_eE?{
return count.intValue(); B+|E|8"
} p8y_uNQE
} /zn|?Y[
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用户在web层构造查询条件detachedCriteria,和可选的 vBsd.2t~
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 WM BntB
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PaginationSupport的实例ps。 w\=zTHo88
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ps.getItems()得到已分页好的结果集 ]@1YgV
ps.getIndexes()得到分页索引的数组 XhFa9RC
ps.getTotalCount()得到总结果数 i7 `dY{p7
ps.getStartIndex()当前分页索引 R3F>"(P@tS
ps.getNextIndex()下一页索引 !c:Q+:,H
ps.getPreviousIndex()上一页索引 Ea1{9>S
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 "|`8mNC
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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 {
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一下代码重构了。 @Fqh]1t
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我把原本我的做法也提供出来供大家讨论吧: exV6&bdu
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首先,为了实现分页查询,我封装了一个Page类: t$r^'ZN
java代码: XETY)<g
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/*Created on 2005-4-14*/ &/R@cS6}'
package org.flyware.util.page; C.s{&
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/** lDV8<
* @author Joa g^8dDY[%
* &KgR;.R^J
*/ -2|D(
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publicclass Page { %Rr!I:[ $
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/** imply if the page has previous page */ :ORCsl6-
privateboolean hasPrePage; wq_c^Ioy
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/** imply if the page has next page */ VP\HPSp
privateboolean hasNextPage; R B.j@*
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/** the number of every page */ 5. :To2
privateint everyPage; -'JTVfm.
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/** the total page number */ :q~qRRmjBe
privateint totalPage; w(r$n|Ks9
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/** the number of current page */ ]l+Bg;F#V
privateint currentPage; P~_CDh.N
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/** the begin index of the records by the current swG^L$r`
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query */ K%qunjv
privateint beginIndex; {d}-SoxH
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/** The default constructor */ p]`pUw{
public Page(){ 84b;G4K
3{Ze>yFE
} OnH>g"
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/** construct the page by everyPage \qQ5x
* @param everyPage KU-z;}9s
* */ A/{pG#if]3
public Page(int everyPage){ IG`~^-}7lR
this.everyPage = everyPage; 2P$l XGjh
} 5YC56,X
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/** The whole constructor */ ,p1 (0i
public Page(boolean hasPrePage, boolean hasNextPage, =/6.4;8
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int everyPage, int totalPage, -c<<A.X
int currentPage, int beginIndex){ @M#2T
this.hasPrePage = hasPrePage; D> Z>4:EM
this.hasNextPage = hasNextPage; Q+mMpI
this.everyPage = everyPage; ZyCAl9{p
this.totalPage = totalPage; P.qD,$-
this.currentPage = currentPage; R|V<2
this.beginIndex = beginIndex; G&D N'bp
} E=~H,~
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/** ^Q!:0D*
* @return +n,8o:fU:
* Returns the beginIndex. ~Zl`Ap
*/ r4+w?=`
publicint getBeginIndex(){ )@eBe^
return beginIndex; |r}%AN6+
} T~"tex]
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/** 8S]Mf*~S'
* @param beginIndex Z ;%
* The beginIndex to set. IL.Jx:(0
*/ m6 hA,li
publicvoid setBeginIndex(int beginIndex){ sB0+21'R
this.beginIndex = beginIndex; cnLC> _hY
} =#BeAsFfO
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/** 3
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* @return [ R~+p#l+Q
* Returns the currentPage. h4?+/jk7
*/ f@LUp^Z/v
publicint getCurrentPage(){ wB9IP{Pf
return currentPage; R%#c~NOO
} ?b#?Vz
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/**
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* @param currentPage
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* The currentPage to set. "3\RJ?eW:S
*/ 7e8hnTzl8<
publicvoid setCurrentPage(int currentPage){ P?9CBhN
this.currentPage = currentPage; EHzZ9zH\
} _'I9rGlx3
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/** 7y[B[$P
* @return _Fz)2h,3
* Returns the everyPage. Ku&(+e
*/ %i.|bIhmm
publicint getEveryPage(){ WZm^:,
return everyPage;
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} ~B=\![
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/** #m$H'O[WG\
* @param everyPage xje{kx#
* The everyPage to set. yLDHJ}R
*/ W!X#:UM)
publicvoid setEveryPage(int everyPage){ cU{LyZp
this.everyPage = everyPage; +Og O<P
} 1Rczf (,aT
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/** Ev^Xs6 }"
* @return ^k_!+8"q{
* Returns the hasNextPage. k&~vVx
*/ s &.Z;X
publicboolean getHasNextPage(){ il#rdJ1@t
return hasNextPage; e<p$Op
} =pk'a_P8-
CC)9Ks\
/** y.O? c&!
* @param hasNextPage r p@=
* The hasNextPage to set. i44:VR|
*/ \6lXsu;I.X
publicvoid setHasNextPage(boolean hasNextPage){ x _2]G'
this.hasNextPage = hasNextPage; ze4/XR
} ?BLOc;I&a
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/** AoR`/tr,
* @return "q(&<+D@
* Returns the hasPrePage. 'P~ *cr ?A
*/ @?1%*/
publicboolean getHasPrePage(){ [=9R5.)c
return hasPrePage; .Z^g
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} B}M J?uvA
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/** TgUQD(d^
* @param hasPrePage 7q\c\qL
* The hasPrePage to set. NNfCJ|
*/ nuC K7X
publicvoid setHasPrePage(boolean hasPrePage){ V`H#|8\i
this.hasPrePage = hasPrePage; {$EXI]f
} I}q-J~s
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/** =.o-R=:d
* @return Returns the totalPage. R80R{Ze
* y&CUT:M6
*/ 9.@(&
publicint getTotalPage(){ fC-^[Af)
return totalPage; p;5WLAF
} b9YpUm7#
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/** gO/(/e>P
* @param totalPage eyE&<:F#J
* The totalPage to set. va<+)b\
*/ $`oA$E3
publicvoid setTotalPage(int totalPage){ ?UxY4m%R;
this.totalPage = totalPage; cpy"1=K~M
} iY($O/G[+
(]V.#JM
} GmHsO/
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PWmz7*/
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 [D,:=p`
N0piL6Js
个PageUtil,负责对Page对象进行构造: 68)^i"DM<
java代码: l6WcnJ
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/*Created on 2005-4-14*/ };j&)M
package org.flyware.util.page; esHiWHAC
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import org.apache.commons.logging.Log; joA+
import org.apache.commons.logging.LogFactory;
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/** em]K7B=
* @author Joa K$
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* gP<_DEd^`
*/ ep?0@5D}]
publicclass PageUtil { xHGoCFB
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privatestaticfinal Log logger = LogFactory.getLog VZ,T`8"
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(PageUtil.class); 9,W-KM
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/** O)Qz$
* Use the origin page to create a new page @(
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* @param page gctaarB&
* @param totalRecords y#0w\/<
* @return j[fQs,efK
*/ LnDj
publicstatic Page createPage(Page page, int QdTe!f|
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totalRecords){ -1:Z^&e/
return createPage(page.getEveryPage(), .#@D n(
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page.getCurrentPage(), totalRecords); (*ng$zZ$
} V\ "5<>+O
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/** vo$66A
* the basic page utils not including exception /4?`F}7)
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handler =#tQIhX`
* @param everyPage DS C4
* @param currentPage !_) ^bRd
* @param totalRecords @QG1\W'
* @return page ~Z2eQx
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*/ PR?clg=z
publicstatic Page createPage(int everyPage, int :#}`uR,D/
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currentPage, int totalRecords){ {*U:Wm<
everyPage = getEveryPage(everyPage); 50&F#v%YB
currentPage = getCurrentPage(currentPage); +][P*/ Ek
int beginIndex = getBeginIndex(everyPage, $at|1+bQ
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currentPage); \DqxS=o;
int totalPage = getTotalPage(everyPage, vI'>$
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totalRecords); X t =bc
boolean hasNextPage = hasNextPage(currentPage, E<uOk
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totalPage); 9C;Y5E~'L
boolean hasPrePage = hasPrePage(currentPage); 3(+#^aw
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returnnew Page(hasPrePage, hasNextPage, 6t:c]G'J
everyPage, totalPage, 'I]"=O,
currentPage, ]5fM?: <l
wF8\
beginIndex); j\f$r,4
} *]WXM.R8
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privatestaticint getEveryPage(int everyPage){ l7,qWSsnK
return everyPage == 0 ? 10 : everyPage; Zk
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} uR@`T18
Qiw4'xQm
privatestaticint getCurrentPage(int currentPage){ t5X
lR]` w
return currentPage == 0 ? 1 : currentPage; |nN/x<v
} io7U[ #
C-u/{CP
privatestaticint getBeginIndex(int everyPage, int Ok&>[qu
HY;?z`=
currentPage){ %uVJLz
return(currentPage - 1) * everyPage; -5 /v`
} ~[TKVjyO
*"FLkC4
privatestaticint getTotalPage(int everyPage, int 2?iOB6
_M[[vXH
totalRecords){ WgJAr73
l
int totalPage = 0; q_y,j&
DXW?;|8)O
if(totalRecords % everyPage == 0) \.P}`Bpa
totalPage = totalRecords / everyPage; G*i# \
else 5jV97x)BGx
totalPage = totalRecords / everyPage + 1 ; :IVMTdYf
3C=clB9<
return totalPage; Ln2C#Uf
} t *
vg]Yc
%K'*P56
privatestaticboolean hasPrePage(int currentPage){ "P5bYq%0v
return currentPage == 1 ? false : true; ?vn 0%e868
} i
`QK'=h[
C2rj ]t
privatestaticboolean hasNextPage(int currentPage, /lB0>Us
F[D0x26^
int totalPage){ XYHCggy
return currentPage == totalPage || totalPage == M
|?p3%
?w37vsN
0 ? false : true; '$h@
} D4Y!,7WEVt
CKt|c!3 7
ESxC{
"
} nP\V1pgA
DJYXC,r
QeeC2
7Sz'vyiz
>'-w%H/
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。 6~h1iY_~
M1]6lg[si
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 YD46Z~$
_8b]o~[Z+
做法如下: {IPn\Bka
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;q,)NAr&
bq3fiT9
的信息,和一个结果集List: 'CX.qxF1;p
java代码:
n22hVw
xcZ%,7
M&djw`B
/*Created on 2005-6-13*/ s>@#9psm
package com.adt.bo; 2Cd
--W+=
TdP{{&'9
import java.util.List; 3H'nRK},
FK@ f'
import org.flyware.util.page.Page; AIl$qPKj&
oIvnF:c
/** vbA7I<;
* @author Joa A2|o=mOH
*/ ))IgB).3M
publicclass Result { 7t-*L}~WA
`@$"L/AJ
private Page page; B}q
X}j'L&{F@
private List content; 0?F@iB~1F
MeI2i
/** &@W4^-9
* The default constructor 2&gVZ z
*/ 9U7Mu;4
public Result(){ YR|(;B
super(); =WmBpUh
} /;<e.
_7=pw5[
/** iVKbGgA
* The constructor using fields QypiF*fSU
* *{.&R9#7U'
* @param page s0)qlm*
* @param content p&OJa$N$[
*/ V+=*2?1
public Result(Page page, List content){ 53`9^|:
this.page = page; 9uw,-0*5
this.content = content; hnsa)@
} @0vC v
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/** iM/*&O}
* @return Returns the content. tB ,.
*/ g]Xzio&w
publicList getContent(){ 68p\WheCal
return content; Qh|-a@
} u+z .J4w
Ufaqhh
/**
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* @return Returns the page. 6VH90KAT
*/ f/0v'
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public Page getPage(){ Siz!/O!'
return page; r*i$+ Z
} kMl @v`
6+Wr6'kuH
/** V#gF*]q
* @param content 6bbZ<E5At
* The content to set. ,5eH2W
*/ ;&+[W(7Sy
public void setContent(List content){ Sv~YFS :oy
this.content = content; @ate49W
} <+?
Y
2fkIdy#n@
/** ~T>jBYI0
* @param page z*M}=`M$
* The page to set. O1x0[sy
*/ 6(N.T+;]
publicvoid setPage(Page page){ + ZR(
this.page = page; C.yY8?|
} 9UeVvH
} "pSH!0Ap\
|D;_:x9
9N~8s6Ob
$6:XsrV\a
wJ80};!
2. 编写业务逻辑接口,并实现它(UserManager, !j!Z%]7
e9~cBG|
UserManagerImpl) ~K5Cr
java代码: =bs.2aN&^
{B FT
v>#Cg\
/*Created on 2005-7-15*/ n!0${QVnS
package com.adt.service; 2Vz'n@g=
zW"~YaO%C
import net.sf.hibernate.HibernateException; ,}9f(`
js:C
mnI
import org.flyware.util.page.Page; OW+ e_im}
v}7@CP]nV
import com.adt.bo.Result; P]pmt1a
x @1px&^
/** tWpl`HH
* @author Joa KI Ek/]<H
*/ gCv"9j<j
publicinterface UserManager { Dk)@>l:gI,
8ivRp<9
public Result listUser(Page page)throws :D"@6PC]
;Y
Dv.I
HibernateException; )8pcf`h{
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} O24Jj\"
b7,
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i Td-n9
qTyg~]e9(
java代码: KK:N [x
u$WBc\j
CnabD{uTf
/*Created on 2005-7-15*/ oJP<'l1
package com.adt.service.impl; >?S\~Y
x Z|&/Ci
import java.util.List; =y?#^
h6g=$8E
import net.sf.hibernate.HibernateException; |n+#1_t%
|.1qy,|!X
import org.flyware.util.page.Page; 98BYtxa
import org.flyware.util.page.PageUtil; $GQphXb$
.W!tveX8-
import com.adt.bo.Result; E;9Z\?P
import com.adt.dao.UserDAO; 8ou e-:/a
import com.adt.exception.ObjectNotFoundException; 4Z*|Dsw
import com.adt.service.UserManager; riID,aut
hZ!oRWIU%G
/** N g58/}zO
* @author Joa y&7YJx
*/ .j:i&j(
publicclass UserManagerImpl implements UserManager { q#;BhPc
:FnOS<_B
private UserDAO userDAO; LFCTr/,
2bWUa~%B
/** -r!42`S
* @param userDAO The userDAO to set. +Qt[1Xq
*/ ]x1p!TSU
publicvoid setUserDAO(UserDAO userDAO){ ^rL,&rk
this.userDAO = userDAO; v#zPH5xo
} !]yQ1@)*'
rqF"QU= l
/* (non-Javadoc) G]b8]3^
* @see com.adt.service.UserManager#listUser mj)PLZ]
i#k-)N _$
(org.flyware.util.page.Page) H \ 3M
*/ _HwpPRVP/
public Result listUser(Page page)throws ]22C)<
qc3~cH.@
HibernateException, ObjectNotFoundException { :#WEx_]
int totalRecords = userDAO.getUserCount(); >b'w'"
if(totalRecords == 0) qB+n6y%
throw new ObjectNotFoundException fVYiwE=F
LaDY`u0G%
("userNotExist"); 9J?W '8s5
page = PageUtil.createPage(page, totalRecords); P2Onkl
List users = userDAO.getUserByPage(page); kg:l:C)Tq
returnnew Result(page, users); Te+^J8
} H-185]7
9X3yp:>V
} \4aKLr
M2dmG<
?!H)zz6y
:.DI_XN`
@YCv
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 g&bwtEZ
`0?^[;[u[
询,接下来编写UserDAO的代码: 85}
ii{S
3. UserDAO 和 UserDAOImpl: bjlkX[{}I
java代码: ms7SoYbSu
z`OkHX*+2|
)i0 $j)R
/*Created on 2005-7-15*/ 3 q"7K
package com.adt.dao; X($6IL6m
rhIGOk1k
import java.util.List; LP ,9<&"<
[%jxf\9jJ_
import org.flyware.util.page.Page; b~j~
Evkt_vvf
import net.sf.hibernate.HibernateException; a!D*)z Y
8[M*
x3
/** %@P``
* @author Joa ?ql2wWsQO
*/ O^0"
publicinterface UserDAO extends BaseDAO { Mb/L~gd"
Z:|9N/>T
publicList getUserByName(String name)throws VJg,~lQN#t
7G"7wYc>R
HibernateException; UQ~4c,
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publicint getUserCount()throws HibernateException; XIRR Al(,
<raG07{!*
publicList getUserByPage(Page page)throws H<Hrwy~
Pcdf$a"`
HibernateException; xg} ug[
<BPRV> 0X
} 4>YU8/Rw
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sMm/4AY]
TP{Gt.e
java代码: T(V8;!
s^cc@C
.H2qs{N!
/*Created on 2005-7-15*/ +zsZNJ(U
package com.adt.dao.impl; w" JGO
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import java.util.List; {5-zyE
h@@d{{IqT
import org.flyware.util.page.Page; *NlpotW,f
&6/%kkv
import net.sf.hibernate.HibernateException; 3 Z1OX]R
import net.sf.hibernate.Query; W' ep6O
J$QBI&D
import com.adt.dao.UserDAO; LN^UC$[tk
{zP#woz2Q
/** 9 mPIykAj8
* @author Joa 'gDe3@ci!
*/ DbtF~`3, .
public class UserDAOImpl extends BaseDAOHibernateImpl 4LsHs
KDD@%E
implements UserDAO { @rwU 1T33
xGRT"U(
/* (non-Javadoc) W2eAhz&
* @see com.adt.dao.UserDAO#getUserByName ~@Kf2dHes
sofu
(java.lang.String) kaQ2A
*/ >]&X ^V%Q#
publicList getUserByName(String name)throws 4o5i ."l
<o0~H
HibernateException { )a cV-+{
String querySentence = "FROM user in class B:9.e?t
f=`33m5
com.adt.po.User WHERE user.name=:name"; SRL-Z&M
Query query = getSession().createQuery vPmnN^
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(querySentence); BU6Jyuwn
query.setParameter("name", name); ^$Krub{|
return query.list(); ssl&5AS
} 8h.V4/?
^%#grX#
/* (non-Javadoc) 'Kz9ygZy
* @see com.adt.dao.UserDAO#getUserCount() {'R)4hL
*/ 'jvpNn
publicint getUserCount()throws HibernateException { rWQY?K@
int count = 0; 8Xn!Kpa
String querySentence = "SELECT count(*) FROM 7[KCWJ
CWlW/>yF
B
user in class com.adt.po.User"; o\6iq
Query query = getSession().createQuery L"vj0@n'0
SW9fE:v
(querySentence); ?)i1b\4Go
count = ((Integer)query.iterate().next it1/3y
=]
(V?@?25
()).intValue(); usOx=^?=
return count; P5?<_x0v4b
} >ttuum12w
Acu@[I^
/* (non-Javadoc) yn~P{}68
* @see com.adt.dao.UserDAO#getUserByPage j*zD0I]
q;A;H)?g
(org.flyware.util.page.Page) CMl~=[foW
*/ 'M/([|@
publicList getUserByPage(Page page)throws K+),?Q
?.p
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HibernateException { 4|Ui?.4=
String querySentence = "FROM user in class 9lspo~M
r:9gf?(&
com.adt.po.User"; *H2]H@QHN
Query query = getSession().createQuery >n$!<
&mkpJF/
(querySentence); %Kto.Xq
query.setFirstResult(page.getBeginIndex()) `fS^
j-_M
.setMaxResults(page.getEveryPage()); n&!+wcJ;Yt
return query.list(); A';QuWdT
} {p/YCch,
]vo_gKZ
} A3+6#?:;
$s gH'/>
T+CajSV
Z[ZDQ o1
g7V_[R(6
至此,一个完整的分页程序完成。前台的只需要调用 <B[G |FY,
va,~w(G
userManager.listUser(page)即可得到一个Page对象和结果集对象 'HaD~pa
4JO@BV >t
的综合体,而传入的参数page对象则可以由前台传入,如果用 +jV_Wz
mEDpKWBk
webwork,甚至可以直接在配置文件中指定。 edpW8eND
^^}Hs-{T
下面给出一个webwork调用示例: VKrShI
java代码: -[]';f4]M
u#jC#u^M
{#hVD4$b
/*Created on 2005-6-17*/ E%3TP_B3
package com.adt.action.user; 7z'ha?
rFu ez$
import java.util.List; -s"0/)HD
!7 _\P7M
import org.apache.commons.logging.Log; }[n5n
import org.apache.commons.logging.LogFactory; /[pqI0sf<A
import org.flyware.util.page.Page; x$B&L`QV
AH d-
import com.adt.bo.Result; WS,7dz
import com.adt.service.UserService; A 's-'8m
import com.opensymphony.xwork.Action; '%7 Bx of
X")|Uw8Kl/
/** Y25uU%6t_
* @author Joa /A07s[L
*/ LmLGki$w
publicclass ListUser implementsAction{ HL 8eD^
\:/Lc{*}MD
privatestaticfinal Log logger = LogFactory.getLog .v])S}K
{fz$Z!8-
(ListUser.class); `W5-.Tv
h;M3yTM-
private UserService userService; oU+F3b}5p
@d&H]5
private Page page; r9@AT(
?R'Y?b
privateList users; # cFr
TFH&(_b
/* 4gZ&^y'
* (non-Javadoc) <z0WLw0'z
* q7Es$zjX
* @see com.opensymphony.xwork.Action#execute() _vl}*/=Hc
*/ `;%Z N
publicString execute()throwsException{ 8<dOMp;}r
Result result = userService.listUser(page); f_\_9o"l
page = result.getPage(); ^jyD#
users = result.getContent(); Ix8$njp[
return SUCCESS; O4|2|sA
} S# we3
&Lj@9\Dh
/** 5:_hP{ @
* @return Returns the page. 1r9 f[j~
*/
|jG~,{
public Page getPage(){ 1oY^]OD]W
return page; HW[L[&/
} a.kbov(
&ab|2*3?X
/** l-O$ m
* @return Returns the users. `
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*/ s&tE_
publicList getUsers(){ qVgd(?hJ#
return users; h @/;`E[
} 2qU&l|>
H^AE|U*-G
/** S4A q'
* @param page Qc"'8kt
* The page to set. =r4!V>
*/ 8q^o.+9
publicvoid setPage(Page page){ g>j| ]6
this.page = page; sqO<J$tz
} 7"2b H
?M}S|dsmE
/** l-)Bivoi
* @param users qx)?buAij
* The users to set. _8fA?q=
*/ JK)qZ=
publicvoid setUsers(List users){ 46x.i;b7
this.users = users; U
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} (q;bg1\UK
6|;Uq'
/** }nrXxfu
* @param userService {aOkV::
* The userService to set. !xK=#pa
*/ eSy(~Y
publicvoid setUserService(UserService userService){ [kB
`
this.userService = userService; <"tDAx
} "@ E3MTW
} ?J!3j{4e
!@L=;1,
ocQWQ
v#oi0-9o[
3S~(:#|
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, 9lzQ\}
q{' ~+Nq
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 < n?=|g
Gt-UJ-RR y
么只需要: $:bih4@>
java代码: mY-hN|
Le#spvV3J|
1|| nR4yK
<?xml version="1.0"?> vF={9G
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork "8<K'zeS8
pbBoy+.>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- {|<"C?
T3,1m=S
1.0.dtd"> K`6z&*
7 &%^>PU7
<xwork> :8f[|XR4\N
E3l*8F%<3
<package name="user" extends="webwork- TkRP3_b
lxb zHlX
interceptors"> v/QUjXBr
*I*i>==Z
<!-- The default interceptor stack name LJTo\^*
2YBIWR8z
--> X_ TiqV
<default-interceptor-ref NC"yDWnO'
rpV1y$n<F
name="myDefaultWebStack"/> ?u$u?j|N
L'A)6^d@S
<action name="listUser" 4,P bg|
URTzX
2'[
class="com.adt.action.user.ListUser"> HEF?mD3h
<param ^4>k%d
-K%5(Eg
name="page.everyPage">10</param> \OwpD,'
<result v/Pw9j!r;m
+s[\g>i
name="success">/user/user_list.jsp</result> 2&LQg=O
</action> FY'dJY3O
$95~5]-nh
</package> blt'={Z?.x
8*a),
3aK
</xwork> .2:\:H~3
O1y|v[-BW
xTV{^=\rS
p.K*UP
*VeW?mY,P
<=um1P3X
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 "MOpsb,
I["j=r
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Qu\@Y[eia5
l?q qqB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 '-PC7"o
gX @`X
QfpuZEUK
Hh[Tw&J4
]!"S+gT*C
我写的一个用于分页的类,用了泛型了,hoho Y%`SHe7M
1T|$BK@)
java代码: 4`v!Z#e/aX
JgfVRqm
&)9{HRP
package com.intokr.util; hlbvt-C?}"
3{7T4p.G
import java.util.List; TpfZ>d2
Ty4S~ClO#'
/** 5]Da{Wmgs
* 用于分页的类<br> .IrNa>J~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 4vZ4/#(x
* #?O&
* @version 0.01 9(_{`2R8
* @author cheng #;VA5<M8
*/ 7L(eh7
public class Paginator<E> { J
m{
privateint count = 0; // 总记录数 ^_5|BT@
privateint p = 1; // 页编号 &Z("D7.G
privateint num = 20; // 每页的记录数 EMvHFu
privateList<E> results = null; // 结果 ,XKCz ]8V
sH#X0fG
/** B|Wk?w.{r\
* 结果总数 : 3ZYJW1
*/ b'p4wE>
publicint getCount(){ DT(d@upH
return count; " {dek
} #CUzuk&
o+ O}Te
publicvoid setCount(int count){ [:;# ]?
this.count = count; C"uahP[Y
} Y$
Fj2nk+
.8gl< vX
/** h) (*q+a
* 本结果所在的页码,从1开始 !kuX,*}q
* /8yn vhF#
* @return Returns the pageNo. QrYa%D+
*/ rfcN/:k
publicint getP(){ {=:#S+^ER
return p; C}}/)BYi
} k%'m *T f
3\$wdUFr
/** 2B1xUj ]
* if(p<=0) p=1 X$?3U!
* 48D?'lW %
* @param p >7Jr^o#|_x
*/ EM j;2!
publicvoid setP(int p){ BzJ;%ywS
if(p <= 0) A&5:ATQ/|
p = 1; 5N7H{vT_
this.p = p; D/(CU#i"
} q1VH5'p@
b{M7w
/** n`7f"'/:
* 每页记录数量 N#xG3zZl|N
*/ ^_+XDO
publicint getNum(){ B}?IEpYp
return num; ;\;M =&{}
} <X7\z
PgM (l3x
/** 1eS_
nLFw~
* if(num<1) num=1 N5U)*U'-u
*/ MmTC=/j
publicvoid setNum(int num){ D1s4`V -
if(num < 1) .3qu9eP
num = 1; 4$6T+i2E
this.num = num; is^pgKX
} b-5y9 K
h11.'Eej`
/** %b2oiKSBx?
* 获得总页数 r{?TaiK
*/ ?
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publicint getPageNum(){ _~'+Qe_o$5
return(count - 1) / num + 1; <PN"oa#
} +_l^ #?o,
9nSWE W
/** J%C#V}z7E
* 获得本页的开始编号,为 (p-1)*num+1 KDP H6
*/ C(T;>if0NH
publicint getStart(){ C#pZw[
return(p - 1) * num + 1; >ezi3Zx^
} rNOES3[~
Ard]147
/** =}!Mf'
* @return Returns the results. Y]|:?G7l]
*/ [/M^[p
publicList<E> getResults(){ WCJxu}!
return results; *LC+ PZV@
} P$GjF-!:
Mj=$y?d ]
public void setResults(List<E> results){ 24c ek
this.results = results; Ey[On^$
} F/d7q%I
y3u+_KY-
public String toString(){ 0U/,aHvhP
StringBuilder buff = new StringBuilder sW#JjtK
PCrU<J 7
(); }G <T :(a
buff.append("{"); 58xnB!h\}
buff.append("count:").append(count); P(k(m<0
buff.append(",p:").append(p); z&8un%Jt
buff.append(",nump:").append(num); `6Qdfmk=
buff.append(",results:").append QnouBrhO
d)o!5L
(results); Ck =;1sGh
buff.append("}"); B$Z3+$hfF
return buff.toString(); '\#EIG
} ?L)
!pP]
RkEN
,xWE
} gR^>3n'
~ (On|h
LjFqZrH