Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 FHqa|4Ie
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 OJQ7nChMm
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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 1 NLawi6
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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 Nr6YQH*[
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。 \d]&}`'4{f
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分页支持类: oI/@w
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java代码: I&1h/
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package com.javaeye.common.util; ,N5Rdgzk
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import java.util.List; qm@c[b
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publicclass PaginationSupport { IeZ}`$[H
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publicfinalstaticint PAGESIZE = 30; 7Ja^d-F7
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privateint pageSize = PAGESIZE; SDcD(G
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privateList items; HOtays,#<}
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privateint totalCount; >{ne!
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privateint[] indexes = newint[0]; ^V_vpr]}P
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privateint startIndex = 0; Op\l
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public PaginationSupport(List items, int fb&K.6"
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totalCount){ OKxPf]~4E
setPageSize(PAGESIZE); ?Ju=L|
setTotalCount(totalCount); C Vyq/X
setItems(items); dD@T}^j *|
setStartIndex(0); sW@4r/F>:D
} UOT~L4G
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public PaginationSupport(List items, int 'hg, W]
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totalCount, int startIndex){ +q1
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setPageSize(PAGESIZE);
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setTotalCount(totalCount); T[~ak"M
setItems(items); QJvA
setStartIndex(startIndex); \E]s]ft;+
} +.b~2K1
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public PaginationSupport(List items, int PHT;%;m=
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totalCount, int pageSize, int startIndex){ vEW;~FLd
setPageSize(pageSize); {SCwi;m
setTotalCount(totalCount); D{PO!WzW
setItems(items); u` R
setStartIndex(startIndex); xa5I{<<U
} D.)R8X
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publicList getItems(){ %~}9#0h)
return items; `SFI\Y+WDT
} &yp_wW-
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publicvoid setItems(List items){ q J@XVN4
this.items = items; "<txg%j\J
} 'FO^VJ;ha
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publicint getPageSize(){ rnEWTk7&
return pageSize; :M'3U g$t
} y~]>J^
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publicvoid setPageSize(int pageSize){ N r
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this.pageSize = pageSize; <+
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} j""u:l^+x
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publicint getTotalCount(){ . m@Sk`s
return totalCount; }#a d
} +'y$XR~W {
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publicvoid setTotalCount(int totalCount){ .y#@~H($
if(totalCount > 0){ p@YU7_sF^!
this.totalCount = totalCount; GwxfnCKi9
int count = totalCount / (VU: &.
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pageSize; dHg[0Br)r
if(totalCount % pageSize > 0) f* p=]]y
count++; <Mxy&9}ic
indexes = newint[count]; `:R8~>p
for(int i = 0; i < count; i++){ $
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indexes = pageSize * +p>tO\mo
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i; AW%^Xt
} ]M-j_("&
}else{ z;2kKQZm
this.totalCount = 0; NIQNzq?a^
} bTb|@
} 8! pfy"
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publicint[] getIndexes(){ D}&U3?g=
return indexes; tb"UGa
} eM*@}3
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publicvoid setIndexes(int[] indexes){ tg7%@SI5^-
this.indexes = indexes; HT[<~c
} :>\ i
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publicint getStartIndex(){ @'7'3+ c
return startIndex; ,4)zn6tC
} }3V Q*'X>i
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publicvoid setStartIndex(int startIndex){ nB`pfg
if(totalCount <= 0) n]r7} 2hM
this.startIndex = 0; roVGS{4T\
elseif(startIndex >= totalCount) .?@$Rd2@W
this.startIndex = indexes :-69,e
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[indexes.length - 1]; tF
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elseif(startIndex < 0) wHEt;rc(
this.startIndex = 0; ![0\m2~iv
else{ OLXG0@
this.startIndex = indexes ,1a6u3f,
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%
[startIndex / pageSize]; 1I<fp $h
} u?&P6|J&
} S)>L 0^M1
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publicint getNextIndex(){ [K9l>O
int nextIndex = getStartIndex() + LeF Z%y)F
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pageSize; )4bBR@QM
if(nextIndex >= totalCount) s%1 O}X$c
return getStartIndex(); qm{(.b^
else to|O]h2*U2
return nextIndex; z)#I"$!d
} ~*79rDs{
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publicint getPreviousIndex(){ si.ZTG9m
int previousIndex = getStartIndex() - iT227v!s
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pageSize; )R(kXz=M
if(previousIndex < 0) wzwEYZN(q
return0; W_Z%CBjcT
else @4#q
return previousIndex; $^?Mip
} .hzzoLI2
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} O&RW[ml*3
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抽象业务类 I}q2)@
java代码: @@-n/9>vs
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/** iVTC"v
* Created on 2005-7-12 07P/A^Mkx
*/ {E@Fk,
package com.javaeye.common.business; ?
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import java.io.Serializable; UyTsUkY
import java.util.List; ]w`)"{j5m
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import org.hibernate.Criteria; #>iBu:\J
import org.hibernate.HibernateException; ywTt<;
import org.hibernate.Session; 7 XE&[o
import org.hibernate.criterion.DetachedCriteria; NvW`x
import org.hibernate.criterion.Projections; 6<u=hhL
import [ uU"=H|
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org.springframework.orm.hibernate3.HibernateCallback; Yd'Fhvo8
import 2FU+o\1%
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org.springframework.orm.hibernate3.support.HibernateDaoS `@TWZ%f6
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upport; tg-U x
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import com.javaeye.common.util.PaginationSupport; .8e]-^Z
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public abstract class AbstractManager extends Z*/{^ zsE
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HibernateDaoSupport { 2 tD{c^
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privateboolean cacheQueries = false; yC \dM1X
+ OKk~GYf
privateString queryCacheRegion; ^/]w}C#:d
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publicvoid setCacheQueries(boolean b3.
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cacheQueries){ I;1W6uD=
this.cacheQueries = cacheQueries; |"}oGL6-
} lCafsIB
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publicvoid setQueryCacheRegion(String gy5 ^JL
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queryCacheRegion){ ^^,cnDlm
this.queryCacheRegion = s>J\h
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queryCacheRegion; >0F)^W?
} M.FY4~
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publicvoid save(finalObject entity){ AQ%B&Q(V1
getHibernateTemplate().save(entity); [~NJf3c"
} i+q tL3
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publicvoid persist(finalObject entity){ ,V^2Oa
getHibernateTemplate().save(entity); N\l|3~
} kB`
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publicvoid update(finalObject entity){ RGgePeaw
getHibernateTemplate().update(entity); Ztl?*zL
} V8nz@
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publicvoid delete(finalObject entity){ Q~R% |Q{&
getHibernateTemplate().delete(entity); ~P7zg!p/q
} a yYl3
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publicObject load(finalClass entity, YsO3( HS
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finalSerializable id){ 8]K+,0m6
return getHibernateTemplate().load 2c*w{\X
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(entity, id); 7}1Z7"?
} :F8h}\a*
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publicObject get(finalClass entity, s6F0&L;N&
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finalSerializable id){ H Y~[/H+:
return getHibernateTemplate().get 1B#iJZ}
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(entity, id); 7@R^B =pb
} }<qZXb1
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publicList findAll(finalClass entity){ ?8qN8rk^+
return getHibernateTemplate().find("from tdHeZv
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" + entity.getName()); EfB.K}b^
} j#~ S"t
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publicList findByNamedQuery(finalString >Hu3Guik]
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namedQuery){ /PVx
return getHibernateTemplate 75pn1*"gQ
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().findByNamedQuery(namedQuery); :-_"[:t 5Z
} K]1|#`n
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publicList findByNamedQuery(finalString query, AC\y|X8-
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finalObject parameter){ Q/@ pcU
return getHibernateTemplate OHwH(}H?
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().findByNamedQuery(query, parameter); bXvriQ.UH
} Es- =0gpK
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publicList findByNamedQuery(finalString query, ]Q,&7D
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finalObject[] parameters){ Hh%"
return getHibernateTemplate Jz4;7/
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().findByNamedQuery(query, parameters); F >H\F@Wl
} l9]nrT1Hy
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publicList find(finalString query){ qC=9m[MI
return getHibernateTemplate().find yRi5t{!V
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(query);
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} xi=0kO
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publicList find(finalString query, finalObject P'[ISGt
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parameter){ KzX)6|g{"
return getHibernateTemplate().find A8QUfg@uK~
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(query, parameter); j >`FZKxp
} TD-B\ @_
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public PaginationSupport findPageByCriteria >Hmho'
P9R-41!
(final DetachedCriteria detachedCriteria){ >0u*E *Y
return findPageByCriteria VU6+"2+'2
T*S)U ;
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 4=%,0.yt
} z8r?C
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public PaginationSupport findPageByCriteria Pqj\vdzx
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(final DetachedCriteria detachedCriteria, finalint `9k\~D=D~
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startIndex){ O>I%O^
return findPageByCriteria ,-kz\N@.
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(detachedCriteria, PaginationSupport.PAGESIZE, \rT>&o .i
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startIndex); kyZZ0
} l^%52m@{
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public PaginationSupport findPageByCriteria ~OLyG$JJ
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(final DetachedCriteria detachedCriteria, finalint IGo5b-ds
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pageSize, 9
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finalint startIndex){ t?b@l<,s
return(PaginationSupport) BlM(Q/z
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate Su[(IMw
* *oDQwW]*
(Session session)throws HibernateException { naA8RD5/
Criteria criteria = ~$rSy|19
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detachedCriteria.getExecutableCriteria(session); 0bD\`Jiv,
int totalCount = ;>fM?ae5
% .ss
((Integer) criteria.setProjection(Projections.rowCount JV8*;n%}-
|N3#of(
()).uniqueResult()).intValue(); >5TXLOYZ
criteria.setProjection &" 5Yt&{
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(null); I"QU{]|J
List items = U'~]^F%eyu
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criteria.setFirstResult(startIndex).setMaxResults _EP~PW#J
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(pageSize).list(); : w>R|]
PaginationSupport ps = ]US!3R^
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new PaginationSupport(items, totalCount, pageSize, T-x9IoE
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startIndex); bweAmSs
return ps; ?%D nIl>
} CHjm7
}, true); <K>qK]|C
} ,% .)mf
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public List findAllByCriteria(final mtw{7E
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DetachedCriteria detachedCriteria){ \JCpwNT{P
return(List) getHibernateTemplate LWN9 D
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().execute(new HibernateCallback(){ ;RQ}OCz9}8
publicObject doInHibernate x cZF_elt7
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(Session session)throws HibernateException { Sw? EF8}[
Criteria criteria = |0X~D}r|J
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detachedCriteria.getExecutableCriteria(session); 6uk}4bdvq
return criteria.list(); m& D#5C
} hx4c`fOs
}, true); Mp[2A uf
} 2p58_^l
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public int getCountByCriteria(final M7-2;MZ
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DetachedCriteria detachedCriteria){ YTr+"\CkA
Integer count = (Integer) ^oClf(
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getHibernateTemplate().execute(new HibernateCallback(){ S&D8Rao5
publicObject doInHibernate <,U$Y>
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(Session session)throws HibernateException { 9g.5:
Criteria criteria = 7?);wh 7`
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detachedCriteria.getExecutableCriteria(session); hZ"Sqm]
return ~]'yUd1gSZ
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criteria.setProjection(Projections.rowCount H6/gRv@
+jKu^f6
()).uniqueResult(); A8:eA
} M)H*$!x}>
}, true); ySF^^X$J
return count.intValue(); Q5sJ|]Bc
} HK%W7i/k@
} 'T;;-M3*
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用户在web层构造查询条件detachedCriteria,和可选的 7 y$a=+D i
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ,R-aO= %
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PaginationSupport的实例ps。 Qd>\{$N
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ps.getItems()得到已分页好的结果集 )CgH|z:=b
ps.getIndexes()得到分页索引的数组 io@f5E+?
ps.getTotalCount()得到总结果数 wzBw5nf\
ps.getStartIndex()当前分页索引 'E\4/0 !
ps.getNextIndex()下一页索引 b/
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ps.getPreviousIndex()上一页索引 w6pXF5ur>
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 z\woTL6D]
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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 8DM! ]L
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一下代码重构了。 0sTR`Xk
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我把原本我的做法也提供出来供大家讨论吧: g!9|1z
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首先,为了实现分页查询,我封装了一个Page类: ?GW}:'z
java代码: dlIYzO<
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/*Created on 2005-4-14*/ 0N$FIw2
package org.flyware.util.page; a,r
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/** 1aCpeD4|)
* @author Joa M|fV7g
* / :6|)AW.{
*/ 0m"Ni:KEf
publicclass Page { +T8MQ[(4
"F6gV;{Bt
/** imply if the page has previous page */ J0oeCb
privateboolean hasPrePage; %l6E0[
}W&9} 9p"
/** imply if the page has next page */ DUh\x>^
privateboolean hasNextPage; E+#<WK-
x":o*(rSQ
/** the number of every page */ YPf?
privateint everyPage; ]vP}K
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/** the total page number */ HIx%c5^
privateint totalPage; t,IOq[Vtk
DfP-(Lm)
/** the number of current page */ Hmt2~>FI[
privateint currentPage; :2&"ak>N
v"Ax'()
/** the begin index of the records by the current S(?A3 H
w( _42)v]g
query */ .Y"F3
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privateint beginIndex; %OHZOs
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/** The default constructor */ ^YropzHZ4E
public Page(){ "H<us?r{
~BX=n9
} \C h01LR"
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/** construct the page by everyPage %W)pZN}
* @param everyPage ^|]Dg &N.
* */ H;l_;c`
public Page(int everyPage){ 2\QsF,@`YU
this.everyPage = everyPage; c38XM]Jeq
} "\KBF
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/** The whole constructor */ D
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public Page(boolean hasPrePage, boolean hasNextPage, ~rJG4U
RZ xwr
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int everyPage, int totalPage, >( [,yMIY
int currentPage, int beginIndex){ ]L7A$sTUQ
this.hasPrePage = hasPrePage; DQm%=ON7
this.hasNextPage = hasNextPage; $i5J}
this.everyPage = everyPage; C5,fX-2Q
this.totalPage = totalPage; ?'9IgT[*
this.currentPage = currentPage; z+yIP ?s}(
this.beginIndex = beginIndex; RbXR/Rd
} d#H9jg15e
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/** }:
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* @return EZ]4cd/i
* Returns the beginIndex. dQ.#8o=
*/ pB8D
publicint getBeginIndex(){ IrqM_OjC
return beginIndex; ,T<JNd'
} #e|o"R;/`
f7lj,GAZ
/** DfD
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* @param beginIndex -HG.GA
* The beginIndex to set. 0lg$zi x(
*/ cR/Nl pX
publicvoid setBeginIndex(int beginIndex){ !i^"3!.l,]
this.beginIndex = beginIndex; ,=P&{38\q
} <$0is:]
$`E?=L`$
/** &aLTy&8Fv
* @return <46&R[17M
* Returns the currentPage. yx :^*/
*/ :ZV|8xI
publicint getCurrentPage(){ >.d/@3
'
return currentPage; w`)5(~b
} ew~Z/ A
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/** AafS6]y
* @param currentPage vW1^
* The currentPage to set. ayy\7b
*/ AG@gOm
publicvoid setCurrentPage(int currentPage){ )!2@v@SQ
this.currentPage = currentPage; -G~]e6:zD
} wUv?;Y$C
d_yvG.#C
/** $r/$aq=K
* @return 4>*=q*<V5E
* Returns the everyPage. ez,.-@O
*/ l{{,D57J
publicint getEveryPage(){ *[Z`0AgP
return everyPage; tYu<(Z(l)
} )@NFV*@I
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/** u}@N
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* @param everyPage &B{zS K$N
* The everyPage to set. q]?qeF[
*/ |g&V? lI
publicvoid setEveryPage(int everyPage){ <=M5)#
this.everyPage = everyPage; 41X`.
} ?+t;\
gk%nF
/** v`A)GnNiN
* @return |[?Otv
* Returns the hasNextPage. I%5vI}
*/ )p\`H;7*V4
publicboolean getHasNextPage(){ fDy*dp4z
return hasNextPage; a
!VWWUTm?
} d%7?913
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/** Z/ q6Q#
* @param hasNextPage wL0[Slf}
* The hasNextPage to set. <?.eU<+O`S
*/ @z1QoZ^w
publicvoid setHasNextPage(boolean hasNextPage){ wN[lC|1c
this.hasNextPage = hasNextPage; 1>Sfv|ZP,
} X
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_E C7r>V&
/** w6vbYPCN
* @return _k@cs^
* Returns the hasPrePage. X:i?gRy"
*/ qO>UN[Y
publicboolean getHasPrePage(){ )\1>)BJq
return hasPrePage; k{ qxsNM
} a=MN:s?Fc0
|vs5N2_
/** AU9C#;JD
* @param hasPrePage b/S:&%E
* The hasPrePage to set. `%Ih'(ne
*/ VIAq$iu7
publicvoid setHasPrePage(boolean hasPrePage){ BN 9e S
this.hasPrePage = hasPrePage; =8]`-(
} x=DxD&I!J
Bp^LLH
/** _lv{ 8vf1B
* @return Returns the totalPage. z*},N$2=
* FyEKqYl
*/ 1/-3m Po
publicint getTotalPage(){ %0Ur3
return totalPage; {)qr3-EM#
} 2y`h'z
IWo'{pk
/** ^%f8JoB
* @param totalPage 'h$1
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* The totalPage to set. W8& )UtWQ
*/ mF
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publicvoid setTotalPage(int totalPage){ {!2K-7;
this.totalPage = totalPage; rUKg<]&@
} B:"D)/\
7NvKpinQ
} gv67+Mf
`3\aX|4@
2K:A4)jZ
(HRj0,/^
beOMln+R
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 &PC6C<<f
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个PageUtil,负责对Page对象进行构造: (G|!{
java代码: ](JrEg$K
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/*Created on 2005-4-14*/ R'gd/.[e
package org.flyware.util.page; if&bp ,
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import org.apache.commons.logging.Log; F3bTFFt
import org.apache.commons.logging.LogFactory; 7hk<{gnr
^Laqq%PI
/** UwUHB~<oE
* @author Joa Zn9u&!T&
* gKb,Vrt
*/ X.<3/
publicclass PageUtil { $#rkvG_w
qm=U<'b^
privatestaticfinal Log logger = LogFactory.getLog h3`}{
w
,>B11Z}PH
(PageUtil.class); B?BOAH
UNDl&C2vz
/** }# s{."
* Use the origin page to create a new page 6w<rSU d'
* @param page %_|KiW
* @param totalRecords Hhtl~2t!0
* @return =2$(
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*/ 1'f_C<.0
publicstatic Page createPage(Page page, int s)WA9PiC
G' U_I
totalRecords){ ]njNSn
return createPage(page.getEveryPage(), f&CQn.K"
O[d#-0s
page.getCurrentPage(), totalRecords); 1%_RXQVG
} i
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l>;hQ h
/** 4$iS@o|
* the basic page utils not including exception (xG%H:6,
"mQp#d/'
handler a]p9[Nk
* @param everyPage o-bH3Jkb]&
* @param currentPage 6>]
* @param totalRecords {@2+oOuYfN
* @return page B .y}S
*/ 6:(s8e
publicstatic Page createPage(int everyPage, int o9}\vN0F
E3 % ~!ZC
currentPage, int totalRecords){ brmSJ7
everyPage = getEveryPage(everyPage); \a+Q5g
currentPage = getCurrentPage(currentPage); 8-@@QZ\N
int beginIndex = getBeginIndex(everyPage, JtO}i{A
},d^y:m
currentPage); K~d'*J-
int totalPage = getTotalPage(everyPage, XYvj3+
(#y2RF8j
totalRecords); g7! LX[
boolean hasNextPage = hasNextPage(currentPage, C<_\{de|9
vD8pVR+
totalPage); %%K3J<5
boolean hasPrePage = hasPrePage(currentPage); }Nr6oUn
KKsVZ~<6u
returnnew Page(hasPrePage, hasNextPage, ^N^G?{EV/#
everyPage, totalPage, sUlf4<_zW
currentPage, [2,D] e
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beginIndex); }K?b2 6`
} ;t*SG*Vi
Gy\]j
privatestaticint getEveryPage(int everyPage){ (l%?YME
return everyPage == 0 ? 10 : everyPage; GeJ}myD O
} s'yR2JYv
2Vti|@JYp
privatestaticint getCurrentPage(int currentPage){ Jk%5Fw0
return currentPage == 0 ? 1 : currentPage; C&yZ` [K
} )(,O~w
4^r6RS@z
privatestaticint getBeginIndex(int everyPage, int =Xvm#/
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currentPage){ IM1&g7Qs2
return(currentPage - 1) * everyPage; /wEl\Kx
} ]){ZL
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privatestaticint getTotalPage(int everyPage, int }Hb0@
b_
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totalRecords){ ?lkB{-%rQ
int totalPage = 0; <n,QSy#
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if(totalRecords % everyPage == 0) *f 7rLM*
totalPage = totalRecords / everyPage; 5Xr})%L
else 6/ 5c|
totalPage = totalRecords / everyPage + 1 ; nl}LT/N
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return totalPage; FaCW +9B
} 07Yak<+~
CmXLD} L_x
privatestaticboolean hasPrePage(int currentPage){ VWzQXo
return currentPage == 1 ? false : true; ^.:&ZsqV
} f?:=@35
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privatestaticboolean hasNextPage(int currentPage, rGQD+ d
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int totalPage){ Fm:Ys](
return currentPage == totalPage || totalPage == @U!&XZ]h
%~:\f#6
0 ? false : true; LCSvw
} +@]k[9
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} eyh}O
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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。 oUn+tu:
J-/w{T8:
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 9{4oz<U
8x-19#
做法如下: /RJ]MQ\*O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 3\4e{3$
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的信息,和一个结果集List: 2H w7V3q
java代码: A{4,ih"5
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/*Created on 2005-6-13*/ t]0DT_iE
package com.adt.bo; E} ]=<8V
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import java.util.List; _IdW5G
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import org.flyware.util.page.Page; KDb j
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/** Q>Klkd5(
* @author Joa /&|p7
*/ . q
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publicclass Result { 31c*^ZE.
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private Page page; VoYL}67c
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private List content; @;Jv/N6@
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/** |hj!NhBe
* The default constructor (/nnN4\=
*/ DzMg^Kp
public Result(){ E9mu:T
super(); h2x9LPLBxT
} baD063P;
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/** ?o.d FKUe
* The constructor using fields N$e
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* mWYrUI
* @param page ]QHp?Ii1
* @param content 5,p;b
*/ EPn!6W5^
public Result(Page page, List content){ ;<m*ASM.3
this.page = page; i$%Bo/Y
this.content = content; W/\VpD) ?;
} !AJkd.
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/** vGlVr.)
* @return Returns the content. (/<Nh7C1c
*/ riOaqV
publicList getContent(){ MvZa;B
return content; L,.~VNy-
} jZ-s6r2=
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/** $%cHplQz5
* @return Returns the page. i,^3aZwJ'
*/ pl3ap(/
public Page getPage(){ Lu6g`O:['
return page; ?e6>dNw
} e`b#,=
{ rLgyrj$
/** xE;O =mI
* @param content b
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* The content to set. g(tVghHxt$
*/ M1WD^?tKQ.
public void setContent(List content){ 5b/ ~]v
this.content = content; -t S\
} :,JjN&
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/** `dcz9 *
* @param page }R16WY_'
* The page to set. o$</At
*/ jr0j0$BF
publicvoid setPage(Page page){ d2Q*1Q@u
this.page = page; 8cOft ;|qB
} @:Zk,
} P~{8L.w!>W
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S=-$:65
2. 编写业务逻辑接口,并实现它(UserManager, uU3A,-{-
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9\o
UserManagerImpl) 7Q&-ObW
java代码: =3(Auchl$Y
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/*Created on 2005-7-15*/ s.bo;lk
package com.adt.service; ?110} [jw
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import net.sf.hibernate.HibernateException; K [DpH&
t?G6|3
import org.flyware.util.page.Page; 2lsUCQI;
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import com.adt.bo.Result; aA#79LS
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/** 1b1Ab
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* @author Joa Q
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*/ seEo)m`d
publicinterface UserManager { T%) E!:}v
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public Result listUser(Page page)throws ?v
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~>(~2083*;
HibernateException; z5$Q"Y.D
^C'0Y.H S
} :+Ukwno?/
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70 7( LG
o p9dYjG7
/_l\7MeI
java代码: BJUj#s0$
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P!|Z%H
/*Created on 2005-7-15*/ PX|@D_%Y=
package com.adt.service.impl; @p*)^D6E\
u5A?; a
import java.util.List; ;9k>;g3m
9(TGkz(NA
import net.sf.hibernate.HibernateException; IANSpWea?
o0 C&ol_
import org.flyware.util.page.Page; 1]G)41
import org.flyware.util.page.PageUtil; q_.fVn:!
d:';s~
import com.adt.bo.Result; sRD
fA4/TF
import com.adt.dao.UserDAO; RJ3oI+gI
import com.adt.exception.ObjectNotFoundException; pc*)^S
import com.adt.service.UserManager; /jGBQ-X
@M"gEeI9
/** )k,n}
* @author Joa DSz[,AaR]
*/ 7tcadXk0
publicclass UserManagerImpl implements UserManager { -Ty~lZ)TDT
!}TsFa
private UserDAO userDAO; kh0cJE\_^
4uIYX
/** [oTe8^@[
* @param userDAO The userDAO to set. !G;u
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*/ {o24A:M
publicvoid setUserDAO(UserDAO userDAO){ ^-Od*DTL
this.userDAO = userDAO; .}!.4J%q2
} 7_i8'(``
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/* (non-Javadoc) ~'_cBJ
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* @see com.adt.service.UserManager#listUser ;yJ:W8U]+;
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(org.flyware.util.page.Page) &+2l#3}
*/ k|)fl l
public Result listUser(Page page)throws ?A3L8^tR
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HibernateException, ObjectNotFoundException { _f[Q\gK
int totalRecords = userDAO.getUserCount(); XH!#_jy
if(totalRecords == 0) KRaL+A
throw new ObjectNotFoundException LQR2T5S/Q,
4qie&:4j
("userNotExist"); F]3Y,{/V
page = PageUtil.createPage(page, totalRecords); s7Agr!>f
List users = userDAO.getUserByPage(page); B`}um;T#~,
returnnew Result(page, users); +Dy^4p?o
} iT-coI
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} '{d@Gc6.
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p)IL(_X)
y>a?<*Y+e
y'_8b=*
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Ym6d'd<9(
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询,接下来编写UserDAO的代码: $6"(t= %{
3. UserDAO 和 UserDAOImpl: /d3Jd.l!
java代码: MoIh=rw
:skR6J
y+(\:;y$7
/*Created on 2005-7-15*/ 3xChik{
package com.adt.dao; =j,WQ66r3
F[jE#M=k
import java.util.List; ,L/ x\_28
|u&cN-}C d
import org.flyware.util.page.Page; P"w\hF
+"?+Be
import net.sf.hibernate.HibernateException; o
<q*3L5
7PY$=L48A
/** 2zTi/&K&
* @author Joa <sH}X$/
*/ !$Nj!
publicinterface UserDAO extends BaseDAO { #V!a<w4_
KrE'M
publicList getUserByName(String name)throws ntW@Fm:bw>
9|+6@6VY!
HibernateException; [*',pG
s6bsVAO>
publicint getUserCount()throws HibernateException; bHwEd%f
m^_=^z+
publicList getUserByPage(Page page)throws Jxe+LG
g@`i7qN
HibernateException; c5YPV"X
Q7s@,c!m_
} Lzq/^&sc(
II\&)_S.4
=c[tHf
Y9+_MxC"
S0,\{j
java代码: HxG8'G
R?xb1yc7_
`S
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