Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v[dUUR f
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 adLL7
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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 CG1MT(V7?
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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 hGtz[u#p
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分页支持类: VN`.*B|9[
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java代码: ibkB>n{(
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package com.javaeye.common.util; ~[;r)
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import java.util.List; sT^R0Q'>
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publicclass PaginationSupport { k]m ~DVS
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publicfinalstaticint PAGESIZE = 30; OZ&/&?!XE
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privateint pageSize = PAGESIZE; u8-6s+
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privateList items; b A+_/1C
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privateint totalCount; 7zu\tCWb
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privateint[] indexes = newint[0]; `~XksyT
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privateint startIndex = 0; 2!#g\"
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public PaginationSupport(List items, int 'z|Da &d P
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totalCount){ g5y+F]'I
setPageSize(PAGESIZE); ajSB3}PN
setTotalCount(totalCount); M@[W"f
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setItems(items); 6KddHyFz
setStartIndex(0); Ci`o;KVj
} f@i#Znkf*?
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public PaginationSupport(List items, int qPDNDkjDD
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totalCount, int startIndex){ lHM+<Z
setPageSize(PAGESIZE); p/Pus;*s
setTotalCount(totalCount); aC1z.?!U
setItems(items); (L(7)WbH
setStartIndex(startIndex); Z9vMz3^N
} -06G.;W\^
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public PaginationSupport(List items, int TiD#t+g
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totalCount, int pageSize, int startIndex){ mG[jR*JW
setPageSize(pageSize); 6 byeO&d
setTotalCount(totalCount); i-|N6J
setItems(items); 7yE\,
setStartIndex(startIndex); z~t0l
} VeQGdyhY
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publicList getItems(){ Mt.Cj;h@^[
return items; /43l}6I
} e]~p:
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publicvoid setItems(List items){ u+8"W[ZULq
this.items = items; hO"!q;<eS
} pS$9mzY
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publicint getPageSize(){ U'=8:&
return pageSize; h$8h@2%
} 3t-STk?
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publicvoid setPageSize(int pageSize){ (WHgB0{
this.pageSize = pageSize; 8H7#[?F
} L\#YFf
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publicint getTotalCount(){ eha|cAq
return totalCount; +u|"q+p
} Jl_W6gY"Z
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publicvoid setTotalCount(int totalCount){ g+B7~Z5,
if(totalCount > 0){ _y4O2n[e
this.totalCount = totalCount; F0!Z1S0g
int count = totalCount / 9"#C%~=+
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pageSize;
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if(totalCount % pageSize > 0) |y^=(|eM
count++; -))S
indexes = newint[count];
h(=<-p@
for(int i = 0; i < count; i++){ A:m+v{*`4
indexes = pageSize *
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i; !h#ZbErW
} T\9[PX<
}else{ tK;xW
this.totalCount = 0; SZH`-xb!+5
} DgT]Nty@b
}
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publicint[] getIndexes(){ ;t0q
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return indexes; NVRzthg%c_
} ^]sb=Amw
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publicvoid setIndexes(int[] indexes){ /3M8;>@u
this.indexes = indexes; 5n?P}kca)
} 4x6n,:;
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publicint getStartIndex(){ Qyw@ r
return startIndex; Y# }qXXZ>]
} 6 J>A U
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publicvoid setStartIndex(int startIndex){ V8/4:Va7s
if(totalCount <= 0) SMrfEmdH+
this.startIndex = 0; z%
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elseif(startIndex >= totalCount) 3O,nNt;L{
this.startIndex = indexes N# }A9t
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[indexes.length - 1]; 8?iI;(
elseif(startIndex < 0) @eJ8wf]
this.startIndex = 0; 5,
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else{
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this.startIndex = indexes JlYZ\
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[startIndex / pageSize]; n~UI47
} wH?)ZL
} + ,Krq 3P
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publicint getNextIndex(){ ^2-
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int nextIndex = getStartIndex() + WO.u{vW]'
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pageSize; Qa,=
if(nextIndex >= totalCount) G%sq;XT61
return getStartIndex(); :^ywc O
else o MJ`_
return nextIndex; eyKxnBz
} Go{,<
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publicint getPreviousIndex(){ n5=U.r
int previousIndex = getStartIndex() - p{5m5x
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pageSize; S46aUkW.
if(previousIndex < 0) O[VY|.MEk
return0; 0Agse)
else <yipy[D
return previousIndex; F
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} >OaD7
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} O2 >c|=#
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抽象业务类 YH\9Je%jx
java代码: ~yJ 2@2I
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/** "jAd.x?X7e
* Created on 2005-7-12 bg Ux&3
*/ $.vm n,:.
package com.javaeye.common.business; 3q73L<f
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import java.io.Serializable; {R ),7U8
import java.util.List; yD~,+}0)
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import org.hibernate.Criteria; V~/G,3:0y%
import org.hibernate.HibernateException; VaD+:b4
import org.hibernate.Session; _CHzwNU
import org.hibernate.criterion.DetachedCriteria; AtJ{d^
import org.hibernate.criterion.Projections; u79- B-YW^
import f(pq`v^-n
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org.springframework.orm.hibernate3.HibernateCallback; #VrIU8Q7'
import
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org.springframework.orm.hibernate3.support.HibernateDaoS t}eyfflZ
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upport; '{AB{)1
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import com.javaeye.common.util.PaginationSupport; qA GjR!=^
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public abstract class AbstractManager extends 12lX-~[["
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HibernateDaoSupport { (|BY<Ac3
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privateboolean cacheQueries = false; ]i#p2?BR
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privateString queryCacheRegion; yIL=jzm`7
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publicvoid setCacheQueries(boolean W+&5G(z~
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cacheQueries){ ]"_c-=
this.cacheQueries = cacheQueries; }AS/^E
} 5z_d$.CIc
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publicvoid setQueryCacheRegion(String m'NAM%$}J
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queryCacheRegion){ MOD&3>NI
this.queryCacheRegion = l?*DGW(t{
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queryCacheRegion; I&+.I K_
} 96^aI1:
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publicvoid save(finalObject entity){ N_T5sZ\
getHibernateTemplate().save(entity); 6=;:[
} $/M-@3wro
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publicvoid persist(finalObject entity){ 5e+j51
getHibernateTemplate().save(entity); !ekByD
} #zl1#TC{(
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publicvoid update(finalObject entity){ kxhsDD$@p
getHibernateTemplate().update(entity); 59oTU
} B2[f1IMI
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publicvoid delete(finalObject entity){ w||t3!M+n
getHibernateTemplate().delete(entity); OV]xo8a;
} <gwRE{6U
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publicObject load(finalClass entity, %NQ%6B
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finalSerializable id){ <uuumi-!%G
return getHibernateTemplate().load NwF"Zh5eMW
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(entity, id); 2G~{x7/[@
} |3FI\F;^q
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publicObject get(finalClass entity, 4fKvB@O@.
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finalSerializable id){ 3wv@wqx
return getHibernateTemplate().get rL-R-;Ca
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(entity, id); Leb
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} 1)=
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publicList findAll(finalClass entity){ iW6O9~
return getHibernateTemplate().find("from ?1ey$SSU]
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" + entity.getName()); futYMoV
} CC=I|/mBM
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publicList findByNamedQuery(finalString E,m|E]WP
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namedQuery){ Dd1k?
return getHibernateTemplate :Vxt2@p{
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().findByNamedQuery(namedQuery); Bb=r?;zjO
} lf`ULY4{
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publicList findByNamedQuery(finalString query, :XY%@n
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finalObject parameter){ a
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return getHibernateTemplate %d+Fq=<
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().findByNamedQuery(query, parameter); yc*cT%?g
} 9CS"s_
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publicList findByNamedQuery(finalString query, $}(Z]z}O ;
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finalObject[] parameters){ ^P9mJ:
return getHibernateTemplate k\O<pG[U
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().findByNamedQuery(query, parameters); Qp<*or@
} "9xJ},:-
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publicList find(finalString query){ ={xRNNUj_
return getHibernateTemplate().find "#E
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(query); LhAN( [
} 1vq2`lWpx
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publicList find(finalString query, finalObject ]lA}5
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parameter){ B5 /8LEWw
return getHibernateTemplate().find "1gIR^S%9
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(query, parameter); ^!B]V>L-
} diNSF-wi,,
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public PaginationSupport findPageByCriteria P.>fkO1\
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(final DetachedCriteria detachedCriteria){ jlb8<xIC]
return findPageByCriteria _i ztQ78
p8 S~`fjV
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0i}.l\
} bDDP:INm.
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public PaginationSupport findPageByCriteria (^~a1@f,J
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(final DetachedCriteria detachedCriteria, finalint 6/cm TT$i
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startIndex){ F7<M{h5s
return findPageByCriteria +On2R&m
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(detachedCriteria, PaginationSupport.PAGESIZE, A@~9r9Uf
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startIndex); IsT}T}p,t
} Uhvy2}w
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public PaginationSupport findPageByCriteria Pm P&Qje7
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(final DetachedCriteria detachedCriteria, finalint <!t;[ie?y
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pageSize, t~qSiHw
finalint startIndex){ 5xr2
return(PaginationSupport) S'RRe84C
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getHibernateTemplate().execute(new HibernateCallback(){ f]10^y5&
publicObject doInHibernate yx#!2Z0hw
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(Session session)throws HibernateException { gGNo!'o
Criteria criteria = 9+(6/<
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = L"0dB.
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((Integer) criteria.setProjection(Projections.rowCount rk%pA-P2
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()).uniqueResult()).intValue(); 0Bgj.?l
criteria.setProjection a:P+HU:
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(null); q !}~c
List items = !gyW15z'
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criteria.setFirstResult(startIndex).setMaxResults O\q6T7bfRW
6GAEQ]
(pageSize).list(); Y, Lpv|
PaginationSupport ps = N\s-{7K
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new PaginationSupport(items, totalCount, pageSize, YO.ddy*59
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startIndex); maSVq G
return ps; UH&1QV
} b!-=L&V
}, true); xGOmvn^lQ
} v#9i|
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public List findAllByCriteria(final w[vccARQ
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DetachedCriteria detachedCriteria){ a"}ndrc*
return(List) getHibernateTemplate ]/p>p3@1C
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().execute(new HibernateCallback(){ -m,Y6
publicObject doInHibernate j7Zv"Vq@
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(Session session)throws HibernateException { ?w'03lr%
Criteria criteria = P7X3>5<;q
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detachedCriteria.getExecutableCriteria(session); H9;IA>
return criteria.list(); uQ
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} yz>S($u
}, true); 1.,KN:qe
} \0i0#Dt9
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public int getCountByCriteria(final AH#a+<;a
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DetachedCriteria detachedCriteria){ y]! #$C /
Integer count = (Integer) e~he#o[%a
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getHibernateTemplate().execute(new HibernateCallback(){ {Gh9(0,B?
publicObject doInHibernate CE
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(Session session)throws HibernateException { lP4s"8E`h
Criteria criteria = Rm_+kp@\
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detachedCriteria.getExecutableCriteria(session); 1LSD,t|
return ,9KnC=_y
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criteria.setProjection(Projections.rowCount !mVq+_7]
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()).uniqueResult(); )yz)Fw|&
} a&kt!%p:
}, true); B$OV^iwxK
return count.intValue(); 4F -<j!
} $Ups9p Q
} i6FJG\d
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用户在web层构造查询条件detachedCriteria,和可选的 );S8`V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 `.~*pT*u
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PaginationSupport的实例ps。 E&"V~
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ps.getItems()得到已分页好的结果集 n%}#e!
ps.getIndexes()得到分页索引的数组 {QN 5QGvK
ps.getTotalCount()得到总结果数 H:Q4!<
ps.getStartIndex()当前分页索引 benqm ~{\
ps.getNextIndex()下一页索引 b!/-9{
ps.getPreviousIndex()上一页索引 O#{`Fj`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 EKuLt*a/
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 =|fB":vk
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一下代码重构了。 roi,?B_8
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我把原本我的做法也提供出来供大家讨论吧: j5smmtM`s
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首先,为了实现分页查询,我封装了一个Page类: 6Xn9$C)
java代码: k5}Qx'/l
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/*Created on 2005-4-14*/ mtLiS3Nk8
package org.flyware.util.page; (6
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/** 3_&s'sG5
* @author Joa Fl(j,B6Z
* 0\k{v
*/ [s]
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publicclass Page { A^|~>9
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/** imply if the page has previous page */
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privateboolean hasPrePage; k|jr+hmn":
.WBp!*4
/** imply if the page has next page */ lG[j,MDs
privateboolean hasNextPage; qJ~fEX
7?vj+1;
/** the number of every page */ @L 6)RF
privateint everyPage; tHM0]Gb}
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/** the total page number */ <a+@4d;
privateint totalPage; B<G,{k
w)R5@
@C*
/** the number of current page */ s._,IW;
privateint currentPage; g">^#^hBE
{=,I>w]T|W
/** the begin index of the records by the current +KTHZpp!c2
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query */ CFoR!r:X
privateint beginIndex; r&F
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/** The default constructor */ nYBa+>3BDf
public Page(){ ^nFP#J)_5
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;-x
} Q^xk]~G$(
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/** construct the page by everyPage v@J[qpX
* @param everyPage ?jvuTS 2
* */ ZhC,nbM
public Page(int everyPage){ oDt{;S8|]
this.everyPage = everyPage; rz%^l1@-
} E>r7A5Uo
*l%&/\
/** The whole constructor */ ^HE@ [b
public Page(boolean hasPrePage, boolean hasNextPage, Z@>kqJ%
s+=':Gcb(C
p3T:Y_
int everyPage, int totalPage, rJRg4Rog
int currentPage, int beginIndex){ ##alzC
this.hasPrePage = hasPrePage; xm=$D6O:
this.hasNextPage = hasNextPage; {/,AMJ<:G]
this.everyPage = everyPage; _lm^v%J$
this.totalPage = totalPage; Zdfh*MHMg
this.currentPage = currentPage; B;piO-hH
this.beginIndex = beginIndex; -]n%+,3L
} y(^\]-fE
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/** Zzb?Nbf
* @return bUYjmb2g)
* Returns the beginIndex. <:8Ew
*/ YJ~mcaw
publicint getBeginIndex(){ U9
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return beginIndex; 0f'LXn
} 59+KOQul6
":GC}VIS
/** C\dk}A
* @param beginIndex iHvWJ<"jR
* The beginIndex to set. MhB>bnWXR
*/ #k)t.P
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publicvoid setBeginIndex(int beginIndex){ k;qWiYMV
this.beginIndex = beginIndex; 3 4&xh1=3
} ~sq@^<M)s
?a1pO#{Dg
/** 9^nRwo
* @return (qz)3Fa
* Returns the currentPage. 7QoMroR
*/ \F""G,AWq{
publicint getCurrentPage(){ U;!J(Us
return currentPage; 8yH)9#>
} 3iL\<^d*ht
!?+q7U
/** IcGX~zWr
* @param currentPage E\p"%
* The currentPage to set. =+q\Jh
*/ o)R<sT
publicvoid setCurrentPage(int currentPage){ G!h75G20
this.currentPage = currentPage; l/\D0\x2
} AD@ {7
( 5uSqw&U
/** (Fq:G) $
* @return 9b@yDq3hQ
* Returns the everyPage. tE-g]y3
*/ M* {5> !\
publicint getEveryPage(){ Z/|=@gpw
return everyPage; :3b02}b7
} W,_2JqQp
<td]k%*+
/** {esb"beGLa
* @param everyPage xH}bX- m
* The everyPage to set. 25@@-2h @
*/ t*u#4I1
publicvoid setEveryPage(int everyPage){ }Gy M<!:
this.everyPage = everyPage; XP?)xDr8
} )OVa7[-T
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/** A
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* @return =q`T|9v
* Returns the hasNextPage. 7T t!hf
*/ ]0j_yX
publicboolean getHasNextPage(){ !]RSG^%s{
return hasNextPage; ~P;A
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} 9.il1mAKg
_+(@?
/** (oG.A
* @param hasNextPage j-DWz>x
* The hasNextPage to set. pVrY';[,|
*/ Uqy/~n-v<
publicvoid setHasNextPage(boolean hasNextPage){ vAqj4:j
this.hasNextPage = hasNextPage; bMNr +N
} m7u`r(&
0z4M/WrNt
/** n=AcN
* @return 2i1xSKRYrD
* Returns the hasPrePage. D!.1R!(Z
*/ w*;"@2y;eY
publicboolean getHasPrePage(){ U%[ye0@:
return hasPrePage; lBAu@M
} nAAv42j[
UT9u?
/** aql8Or1[
* @param hasPrePage Y:, rN
* The hasPrePage to set. <gfRAeXA
*/ V*@Y9G
publicvoid setHasPrePage(boolean hasPrePage){ {IaDZ/XS6
this.hasPrePage = hasPrePage; '3WtpsKA
} ^w2 HF
n;Q8Gg2U
/** c %Cbq0+2
* @return Returns the totalPage. kxJ[Bi#
* j0V/\Ep)T<
*/ Pd(_
publicint getTotalPage(){ tMp!MQ
return totalPage; {*[(j^OE
} { I\og
SY%y *6[6
/** 0y?;o*&U\
* @param totalPage pRL:,q\
* The totalPage to set. ( }Bb=~
*/ W I MBwmg
publicvoid setTotalPage(int totalPage){ bv b\G
this.totalPage = totalPage; z ynu0X
} G9yK/g&q
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} +@?'dw
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y$SUYG'v
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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 $~W5! m
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个PageUtil,负责对Page对象进行构造: =!xX{o?64
java代码: *kg->J
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/*Created on 2005-4-14*/ l:uQ#Z)
package org.flyware.util.page; V
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import org.apache.commons.logging.Log; >X'-J{4R
import org.apache.commons.logging.LogFactory; $D#h, `
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/** k%i.B
* @author Joa 3?I!
* FiUwy/,ZV
*/ !*NDsC9
publicclass PageUtil { \y]K]iv
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privatestaticfinal Log logger = LogFactory.getLog e5P9P%1w
ipbhjK$
(PageUtil.class); d(d<@cB9
/bB4ec8!
/** KvPCb%!ZP
* Use the origin page to create a new page orH6R8P]
* @param page >(S)aug$1
* @param totalRecords tm^joK[{|J
* @return ZL\^J8PRK
*/ , 6X;YY
publicstatic Page createPage(Page page, int
h-?yed*?
jqc}mI\#
totalRecords){ _lwKa,}
return createPage(page.getEveryPage(), a*U[;(
jTIG#J)
page.getCurrentPage(), totalRecords); ~$5XiY8A
} *qy \%A
i\ X3t5
/** 85q/|9D
* the basic page utils not including exception YRX^fZ-b
,v>;/qm
handler %\HPYnIe
* @param everyPage 8Sj<,+XFq
* @param currentPage wGKxT
ap
* @param totalRecords a(]&H
"
* @return page pka^7OWyN
*/ ~1wt=Ln>
publicstatic Page createPage(int everyPage, int tjb$MW$('
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currentPage, int totalRecords){ A%Ka)UU+n
everyPage = getEveryPage(everyPage); Pg(Y}Tu
currentPage = getCurrentPage(currentPage); oMj"l#a*
int beginIndex = getBeginIndex(everyPage, uH%b rbrU
PR:B6 F8
currentPage); A+* lV*@0
int totalPage = getTotalPage(everyPage, Mh-"B([Z
Sl,DZ!
totalRecords); ocZ}RI#Q
boolean hasNextPage = hasNextPage(currentPage, ?%hd3zc+f
^]R_t@
totalPage); VPYLDg.'
boolean hasPrePage = hasPrePage(currentPage); *m+FMyr
9U6$-]J
returnnew Page(hasPrePage, hasNextPage, bHnKtaK4c
everyPage, totalPage, <m`CLVx8m
currentPage, /-[vC$B"
iIX%%r+
beginIndex); A'z]?xQR
} D!,5j_,j%
K}re{y
privatestaticint getEveryPage(int everyPage){ Q:megU'u
return everyPage == 0 ? 10 : everyPage; }
u;{38~
} oOpEpQ}}q
lt6wmCe
privatestaticint getCurrentPage(int currentPage){ "gM!/<~
return currentPage == 0 ? 1 : currentPage; Za|iU`e\
} NeY*l
1n^N`lD8]6
privatestaticint getBeginIndex(int everyPage, int 20|_wAA5
!<:Cd(bM
currentPage){ XKky-LeJ
return(currentPage - 1) * everyPage; <$z[pw<
} bTimJp[b
C`i#7zsH
privatestaticint getTotalPage(int everyPage, int =|1_6.tz
5_E8
RAG
totalRecords){ Eb[;nk?
int totalPage = 0; t;w<n"
<PDCM8
if(totalRecords % everyPage == 0) !?JZ^/u
totalPage = totalRecords / everyPage; |> STb\
else 94#,dA,M
totalPage = totalRecords / everyPage + 1 ; IdAh)#)
7
yO%^[c?
return totalPage; ?m]vk|>
} Dnw^H.
{. 9BG&
privatestaticboolean hasPrePage(int currentPage){ auK9wQ%\
return currentPage == 1 ? false : true; \{ EVRRXn
} gPk,nB
mc?IM(t
privatestaticboolean hasNextPage(int currentPage, yl~;!
_D{A`z
int totalPage){ erEB4q+ #O
return currentPage == totalPage || totalPage == _`?cBu`
(yP1}?
0 ? false : true; d9v66mpJM
} <?7qI8 5OT
IsI5c
yHw @Z
} m)p|NdTZc8
(dSYb&]
)\u%XFPhS
G]rY1f0
t/Io.d
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。 MygAmV&
9
fB|e|
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 '9f0UtT|[
>va_,Y}
做法如下: =fRS UtX
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 aJ(/r.1G
Y`j$7!j
的信息,和一个结果集List: L'{W|Xb+
java代码: c<|y/n
crb^TuN
5/'Q0]4h
/*Created on 2005-6-13*/ hxL?6mhY
package com.adt.bo; HfSx*@\s
b=lJ`|
import java.util.List; 59)w+AW
R*:$^v@4
import org.flyware.util.page.Page; no<$=(11i
NRtH?&7
/** r=n{3o+
* @author Joa 17KQ
*/ 9$HKP9G
publicclass Result { h<%$?h+}
4u}Cki,vOK
private Page page; =_-u;w1D
akyMW7'3V<
private List content; bp9RF
d{
>p-UQc
/** 6a,8t
* The default constructor o664b$5nsI
*/ :%sBY0 yF
public Result(){ h}SZ+G/L
super(); jXA/G%:[
} aNu.4c/5
I^k&v V
/** @)h>vg
* The constructor using fields 06Wqfzceb
* $4g{4-)
* @param page o^2MfFS
* @param content Yt#;
+*d5
*/ F0_w9"3E~
public Result(Page page, List content){ fU|v[
this.page = page; .S|7$_9;b
this.content = content; Jd7chIK
} s*Qyd{"z
y-+W
/** N0S^{j,i
* @return Returns the content. ;VKWY
*/ t~ {O)tt
publicList getContent(){ ( 5!'42
return content; 2JK
'!Ry)
} s_y8+BJaV
vcu@_N 1Dc
/** +w]#26`d
* @return Returns the page. Cik1~5iF
*/ As46:<!2
public Page getPage(){ <w^u^)iLy1
return page; -O$vJ,*
} H};1>G4
f9K7^qwkiz
/** VrRF2(Kn?
* @param content zF`a:dD$d
* The content to set. n{TWdC
*/ o~XK*f=(
public void setContent(List content){ JY CMW!~
this.content = content; ];w}?LFb
} 2om:S+3)2
4ekwmw(ox
/** Cl&mz1Y;]1
* @param page ZJ%NZAxy
* The page to set. ppz3"5
*/ %l!A%fn(
publicvoid setPage(Page page){ imif[n+]}d
this.page = page; l[i4\ CT
} \#%GVru!
} Y!xPmL^]?
'zm5wqrkAd
}MOXJb @
op`9(=DJ]
3/]1m9x
2. 编写业务逻辑接口,并实现它(UserManager, "B:FSWM_-
[Ep'm
UserManagerImpl) rEWJ3*Hb
java代码: "yQBHYP
[mv? \HDa~
9
3)fC
/*Created on 2005-7-15*/ ^Saf
z8-3o
package com.adt.service; *4
LS``
K[iAN;QCe%
import net.sf.hibernate.HibernateException; ]|!|3lQ
nPvys~D
import org.flyware.util.page.Page; mBwz.KEm<
8D)1ZUx7`
import com.adt.bo.Result; 2Jt{oh |
;l!<A
/** 3H!]X M
* @author Joa i_N8)Z;r
*/ HFP'b=?`]|
publicinterface UserManager { AI3x,rk#
;wMu
public Result listUser(Page page)throws ZS+m}.,whQ
8i[TeW"
HibernateException; Kuh3.1#o
H(;@7dh
} $!wU[/k
W<)nC_$
2z
!05]B%
L~PiDQr?r
{g nl6+j
java代码: _0$>LWO~
GY?u+|Q
~v(c9I)
/*Created on 2005-7-15*/ 7u;N/@
package com.adt.service.impl; 05H:ZrUV
2+y wy^
import java.util.List; ied1+H
>g !Z|ju
import net.sf.hibernate.HibernateException; b/[X8w'VP
'sZGLgT;m
import org.flyware.util.page.Page; -KC@M
import org.flyware.util.page.PageUtil; @}6<,;|DQ
H,TApF89A
import com.adt.bo.Result; "=DQ { (L
import com.adt.dao.UserDAO; WwsNAJ
import com.adt.exception.ObjectNotFoundException; 1f+A_k/@
import com.adt.service.UserManager; ,X3D<wl
3A^AEO
/** kkZ}&OXS;
* @author Joa L@O>;zp;
*/ +PE-j| D
publicclass UserManagerImpl implements UserManager { BC!) g+8
C _he=SV
private UserDAO userDAO; =SmU;t>t/
S}rEQGGR{
/** kO}%Y?9d
* @param userDAO The userDAO to set. ZgEV-.>P
*/ =KQIrS:
publicvoid setUserDAO(UserDAO userDAO){ SM)"vr_
this.userDAO = userDAO; 69$R.
} EE]xZz>o
1/mBp+D
/* (non-Javadoc) >[wxZ5))
* @see com.adt.service.UserManager#listUser h{7>>
`\(co;:
(org.flyware.util.page.Page) 4~1b
*/ KKk~vwW
public Result listUser(Page page)throws }JtcAuQt
Z{vc6oj
HibernateException, ObjectNotFoundException { u:J(0re
int totalRecords = userDAO.getUserCount(); TI8\qIW
if(totalRecords == 0) 5yt= ~
throw new ObjectNotFoundException i
Ehc<
[ p,]/ ^ N
("userNotExist"); 'V%w{ZiiV
page = PageUtil.createPage(page, totalRecords); #tg\
bb
List users = userDAO.getUserByPage(page); OMk3\FV2Z
returnnew Result(page, users); ^|oI^"IQ=
} afHRy:<+%
bK }ZR*)
} .B xQF
6, j60`f)
kVZs:
3c#^@Bj(-e
H.iCYD_=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >A@yF?
+a,#BSt
询,接下来编写UserDAO的代码: #QsJr_=
3. UserDAO 和 UserDAOImpl: Hc8^w6S1@
java代码: 82 |^o
"Ia.$,k9
R%r25_8
/*Created on 2005-7-15*/ bn|HvLQ"1
package com.adt.dao; pvl];w
f9UDH8X
import java.util.List; ~rI2 RJ
6wpu[
import org.flyware.util.page.Page; fk15O_#3
P%&|?e~D^
import net.sf.hibernate.HibernateException; 9[\do@
:I"22EH
/** TT9
\m=7
* @author Joa aC' 6
*/ g:~q&b[q6
publicinterface UserDAO extends BaseDAO { bHm/Z Zx
kK4+K74B
publicList getUserByName(String name)throws ZYY~A_C
Z2*?a|3
HibernateException; 0VQBm^$(
z2Wblh"_
publicint getUserCount()throws HibernateException; +fM8
#l+Rs3T:
publicList getUserByPage(Page page)throws AW\uE[kg
2sgp$r
HibernateException; VDv.N@)7
zk3\v
"
} 8(-
29
4 5wqX h
_~tF2`,Y_p
Ha]vG@?+
416}# Mk
java代码: Pbbi*&i
}LS.bQKqi,
?`Mk$Y%my
/*Created on 2005-7-15*/ |Wck-+}U
package com.adt.dao.impl; ^GYVRD
POc<XLZB
import java.util.List; Q;l%@)m+~
N!<l~[rc
import org.flyware.util.page.Page; x ]}'H
zN5};e}^v
import net.sf.hibernate.HibernateException; Iao?9,NL9O
import net.sf.hibernate.Query; IC"ktv bHz
2h<_?GM\s
import com.adt.dao.UserDAO; Iw?f1]
A>Qu`%g*
/** n>B
,O
* @author Joa (gE<`b
*/ 6b2h\+AP
public class UserDAOImpl extends BaseDAOHibernateImpl !S7?:MJ?p\
Z$c&Y>@)
implements UserDAO { *C|*{!
T>*G1 -J#
/* (non-Javadoc) ?HOnDw.v1
* @see com.adt.dao.UserDAO#getUserByName GNwFB)?j
/EQ^-4yr
(java.lang.String) }jce5E
*/ ^wSGrV'
publicList getUserByName(String name)throws -/B*\X[
I4ZbMnO
HibernateException { 6^jrv [d
String querySentence = "FROM user in class ;D-k\kv
xh<{lZ)KJ
com.adt.po.User WHERE user.name=:name"; 3HR)H-@6@7
Query query = getSession().createQuery +3AX1o%p,#
Hsov0
(querySentence); (6H7?nv
query.setParameter("name", name); =],c$)
return query.list(); Z
s|*+[
} |'o<w
]hc
h)W#
/* (non-Javadoc) 5i{J0/'Xu)
* @see com.adt.dao.UserDAO#getUserCount() sm[zE/2b
*/ FncP,F$8
publicint getUserCount()throws HibernateException { <o|k'Y(-
int count = 0; "5$p=|
String querySentence = "SELECT count(*) FROM L`O7-'`
#/9Y}2G|]
user in class com.adt.po.User"; Iq19IbR8
Query query = getSession().createQuery F 3q<j$y
fpZHE=}r
(querySentence); A=ez,87
count = ((Integer)query.iterate().next Zn*W2s^^{
(}T},ygQ
()).intValue(); |V}tTx1
return count; sGiK
S,.K
} :KRNLhWb
I_?R(V[9
/* (non-Javadoc) Rm,>6bQx
* @see com.adt.dao.UserDAO#getUserByPage g hkV^ [
c9nv=?/}f
(org.flyware.util.page.Page) )FA:wsy~E
*/ FW3E UC)P
publicList getUserByPage(Page page)throws m4~~ q[t
R;U4a2~
HibernateException { 2Z"\%ZD
String querySentence = "FROM user in class F!?f|z,/
@3b @]l5
com.adt.po.User"; %/nDG9l
Query query = getSession().createQuery K'E)?NW69
v3n
T@ra'
(querySentence); KL(sVj^e
query.setFirstResult(page.getBeginIndex()) >x~Qa@s;
.setMaxResults(page.getEveryPage()); A'u]z\&%c
return query.list(); -m=!SQ >9
} DtS7)/<T
I+^iOa
} PbxQ \.
-
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i
z~2;u5S&
PRyzvc~
VggSDb
至此,一个完整的分页程序完成。前台的只需要调用 J5f}-W@
Kxh WZ3
userManager.listUser(page)即可得到一个Page对象和结果集对象 vkYiO]y
g^=Ruh+
的综合体,而传入的参数page对象则可以由前台传入,如果用 Ya<V@qd
,k@iNid
webwork,甚至可以直接在配置文件中指定。 7''iT{-[p
c&<Ei1
下面给出一个webwork调用示例: D^t:R?+
java代码: l\m7~
YiL^KK
Kj?hcGl[
/*Created on 2005-6-17*/ hv|-`}#0
package com.adt.action.user; ycIcM~<4
1Z(9<M1!M
import java.util.List; w:1UwgcPC
]_!NmB_3
import org.apache.commons.logging.Log; \x\(36\u
import org.apache.commons.logging.LogFactory; @,G\`;Ma
import org.flyware.util.page.Page; LH@Kn?R6
xA*6Z)Y
import com.adt.bo.Result; AS4oz:B
import com.adt.service.UserService; )T
slI
import com.opensymphony.xwork.Action; m("KLp8
9*!*n ~
/** 5lwMc0{/3
* @author Joa
,HNk<W
*/ "r@G V5ED
publicclass ListUser implementsAction{ N
/;Vg^Wx
7^#O{QYol
privatestaticfinal Log logger = LogFactory.getLog (\
|Go-2G
rof9Rxxe-
(ListUser.class); ME5M;bz(
PyQ\O*
private UserService userService; G ,`]2'(@
&g8