Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :C^{Lc
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 t$qIJt$
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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 j+'ua=T3
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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 *# <%04f
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分页支持类: An>ai N]
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java代码: b`%u}^B {
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package com.javaeye.common.util; V%[t'uh
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import java.util.List; U}HSL5v
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publicclass PaginationSupport { q8ZxeMqx%
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publicfinalstaticint PAGESIZE = 30; ]Ls T
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privateint pageSize = PAGESIZE; `dF~'
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privateList items; [ {"x{;
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privateint totalCount; :icpPv
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privateint[] indexes = newint[0]; JkR%o
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privateint startIndex = 0; S7j(4@
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public PaginationSupport(List items, int {pi_yr3
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totalCount){ wGMoh.GTh
setPageSize(PAGESIZE); ;*K;)C
setTotalCount(totalCount); 3;b)pQ~6CJ
setItems(items); C &@'oLr
setStartIndex(0); 1LFad>`
} 'H`:c+KDG`
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public PaginationSupport(List items, int `tO t+>YWn
@lM-+q(tl
totalCount, int startIndex){ B]hRYU
setPageSize(PAGESIZE); ,;YNI
setTotalCount(totalCount); 3
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setItems(items); ~%tVb c
setStartIndex(startIndex); (e_p8[x
} VxOWv8}|
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public PaginationSupport(List items, int ;L",K?6#
|j/Y#.k;{0
totalCount, int pageSize, int startIndex){ f@9XSZ<.71
setPageSize(pageSize); 1Q^u#m3
setTotalCount(totalCount); nT4Ryld
setItems(items); Ht43G_.j
setStartIndex(startIndex); }X])055S
} AEf[:]i]
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publicList getItems(){ 'rXf
return items; f3vl=EA4|
} z+M{zr
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publicvoid setItems(List items){ _"H\,7E
this.items = items; &RuTq6)r
} $uwz`N:
,|8aDL?
publicint getPageSize(){ C:AV?
return pageSize; (VkO[5j
} r1.zURY
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publicvoid setPageSize(int pageSize){ |gk4X%o6
this.pageSize = pageSize; LB.B w
} +F,])p4,]i
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publicint getTotalCount(){ uDcs2^2l
return totalCount; D'moy*E
} rkh%[o9"/
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publicvoid setTotalCount(int totalCount){ F&CvqPI
if(totalCount > 0){ ZJFF4($qN
this.totalCount = totalCount; >^W6'Q$P<
int count = totalCount / vEG7A$Z"
fGH)Fgo`
pageSize; #u"@q< )
if(totalCount % pageSize > 0) FP y}Wc*UA
count++; fhdqes])
indexes = newint[count]; rT-.'aQ2t
for(int i = 0; i < count; i++){ t0xE
indexes = pageSize * W}7Uh
b
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i; x~m$(LT
} ~Sf'bj;(
}else{ 7F2:'3SQ
this.totalCount = 0; 3DCR n :
} ze
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} 4!3<[J;N;
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publicint[] getIndexes(){ :|&6x!
return indexes; 7c%dSs6
} W4#DeT
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publicvoid setIndexes(int[] indexes){ AfZGI'%4[a
this.indexes = indexes; 18kWnF]n=
} t\2-7Ohj6
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publicint getStartIndex(){ Mc8_D,7
return startIndex; ,9F3~Ryt(
} ^G5 fs'd
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publicvoid setStartIndex(int startIndex){ ]
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if(totalCount <= 0) -ciwIS9L
this.startIndex = 0; z 36Y/{>[
elseif(startIndex >= totalCount) Uw5&.aqn.b
this.startIndex = indexes {w,^Z[<
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[indexes.length - 1]; Mx# P
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elseif(startIndex < 0) fS8Pi,!
this.startIndex = 0; V'za,.d-
else{ xrlyph5mE
this.startIndex = indexes Hit)mwfYE
p vWj)4e
[startIndex / pageSize]; 5>H&0> \
} :: GW
} -IDhK}C&T
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publicint getNextIndex(){ 0>;[EFL
int nextIndex = getStartIndex() + 7)> L#(N
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pageSize; MCXt,`}[
if(nextIndex >= totalCount) 8{%&P%vf
return getStartIndex(); tmeg=U7
else 7bVKH[
return nextIndex; u#V;
} gH"aMEC
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publicint getPreviousIndex(){ }lq$Fi/
int previousIndex = getStartIndex() - WhFE{-!gX
OzH\YN
pageSize;
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if(previousIndex < 0) 3UQBIrQ
return0; l Ny<E!0
else LR4W
return previousIndex; n(n7"+B
} #!m^EqF1_
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} Y_XRf8Sw
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抽象业务类 !QqVJ a{j
java代码: od !s5f!
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/** G!D~*B9G
* Created on 2005-7-12 ]r#NjP
*/ :4\_upRE
package com.javaeye.common.business; FELW?Q?k
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import java.io.Serializable; SM<qb0
import java.util.List; ;ae6h
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import org.hibernate.Criteria; daf-B-
import org.hibernate.HibernateException; ,z((?h,nm
import org.hibernate.Session; e)L!4Y44K
import org.hibernate.criterion.DetachedCriteria; q #8z%/~k
import org.hibernate.criterion.Projections; !:_krLB<
import !l9#a{#6l
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org.springframework.orm.hibernate3.HibernateCallback; Pi%-bD/w
import V Kc`mE
D{+D.4\
org.springframework.orm.hibernate3.support.HibernateDaoS 1P BnGQYM
F=UW[zy/[
upport; pC&i!la{o}
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import com.javaeye.common.util.PaginationSupport; [eDRghK
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public abstract class AbstractManager extends Lk)TK/JM)
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HibernateDaoSupport { TP`"x}ACa?
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privateboolean cacheQueries = false; j{m{hVa
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privateString queryCacheRegion; iZ(p]0aP7
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publicvoid setCacheQueries(boolean EYZ,GT-I
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cacheQueries){ I(9+F
this.cacheQueries = cacheQueries; ^w*vux|F
} s21)*d
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publicvoid setQueryCacheRegion(String #vR5a}BAk
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queryCacheRegion){ A.!3{pAb
this.queryCacheRegion = ?CpM.{{s
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queryCacheRegion; ;tZ 8Sh)
} ggHl{cl)
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publicvoid save(finalObject entity){ n+'s9
getHibernateTemplate().save(entity); t.7_7`bin~
} tkHUX!Ow;
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publicvoid persist(finalObject entity){ r"lh\C|
getHibernateTemplate().save(entity); q(5
} Wk/Il^YG
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publicvoid update(finalObject entity){ z9zo5Xc=
getHibernateTemplate().update(entity); lF$$~G
} 1a#R7chl
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publicvoid delete(finalObject entity){ )U2%kmt
getHibernateTemplate().delete(entity); Z1DF )
} &Qv%~dvW
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publicObject load(finalClass entity, aS+i`A :a
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finalSerializable id){ x=Ez hq]X
return getHibernateTemplate().load TyaK_XW
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(entity, id); >DR/lBtL
} 3^F1 hCB
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publicObject get(finalClass entity, 0MOn>76$N
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finalSerializable id){ ;BEX|wxn
return getHibernateTemplate().get CWE^:kr6
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(entity, id); .1""U
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} i#Fe`Z ~J
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publicList findAll(finalClass entity){ Lor__
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return getHibernateTemplate().find("from /.m}y$@GV
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" + entity.getName()); JjQTD-^
} K`cy97
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publicList findByNamedQuery(finalString G*^4CJ
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namedQuery){ |Fzt|
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return getHibernateTemplate &. "ltB
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().findByNamedQuery(namedQuery); rK
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} 5{M$m&$1
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publicList findByNamedQuery(finalString query, +
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finalObject parameter){ o){<PN|z
return getHibernateTemplate nZkMyRk
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().findByNamedQuery(query, parameter); -k@Uo(MB
} ch0x*[N@
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publicList findByNamedQuery(finalString query, T;B/Wm!x
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finalObject[] parameters){
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return getHibernateTemplate xh!aB6m8R
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().findByNamedQuery(query, parameters); q62U+o9G
} ]+AgXUrbOD
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publicList find(finalString query){ ; HjT
return getHibernateTemplate().find 2v1dSdX,W
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(query); vXcgl
} 4ak} "Z
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publicList find(finalString query, finalObject [[8h*[:
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parameter){ v|YJ2q?19
return getHibernateTemplate().find 7o`pNcabtz
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(query, parameter); .h;X5q1
} <p8>"~R
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public PaginationSupport findPageByCriteria Y@V6/D} 1
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(final DetachedCriteria detachedCriteria){ \AB*C_Ri
return findPageByCriteria ;Q%3WD
+P"u1q*+p
(detachedCriteria, PaginationSupport.PAGESIZE, 0); e\i}@]
} (`K~p Z
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public PaginationSupport findPageByCriteria l`RFi)u~&
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(final DetachedCriteria detachedCriteria, finalint '3ZYoA%
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startIndex){ cjBHczkY
return findPageByCriteria #h7$b@
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(detachedCriteria, PaginationSupport.PAGESIZE, <=!|U0YV
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startIndex); pB0Do6+{
} tsqWnz=)
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public PaginationSupport findPageByCriteria W|[k]A` 2
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(final DetachedCriteria detachedCriteria, finalint 3`Q>s;DjIU
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pageSize, I'16-
finalint startIndex){ H.:
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return(PaginationSupport) m3iB`
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getHibernateTemplate().execute(new HibernateCallback(){ ZlsdO.G
publicObject doInHibernate ~m@w p
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(Session session)throws HibernateException { s$;IR
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Criteria criteria = aQhr$aH
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detachedCriteria.getExecutableCriteria(session); DYvg ^b
int totalCount = 4xNzhnp|
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((Integer) criteria.setProjection(Projections.rowCount <\5Y~!)
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()).uniqueResult()).intValue(); >iB-gj}>X
criteria.setProjection b'~IFNt*^
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(null); 9 k>=y n
List items = |{@_J
-)ag9{ *
criteria.setFirstResult(startIndex).setMaxResults QG=&{-I~[3
SB` "%6
(pageSize).list(); " ^:$7~%bA
PaginationSupport ps = |MXv
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new PaginationSupport(items, totalCount, pageSize, Pxm~2PAm
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startIndex); ;P4tqY@
return ps; ym)`<[T
} Z
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}, true); GCEq3
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} #T8$NZA
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public List findAllByCriteria(final mh8~w~/[
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DetachedCriteria detachedCriteria){ We*)RXm%
return(List) getHibernateTemplate n/]$k4h
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().execute(new HibernateCallback(){ g$ oe00b
publicObject doInHibernate )z#M_[zC>
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(Session session)throws HibernateException { juuV3et
Criteria criteria = iy_\1jB0
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detachedCriteria.getExecutableCriteria(session); |+MV%QG;
return criteria.list(); Qvd$fY**
} 35[8XD
}, true); mjqVP.
} t7p`A8&
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public int getCountByCriteria(final _('KNA~
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DetachedCriteria detachedCriteria){ jHx<}<
Integer count = (Integer) :i6k6=
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getHibernateTemplate().execute(new HibernateCallback(){ $yx34=
publicObject doInHibernate sR. ecs+
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(Session session)throws HibernateException { pMX#!wb
Criteria criteria = z<F.0~)jb
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detachedCriteria.getExecutableCriteria(session); lAwOp
return e[@q{.
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criteria.setProjection(Projections.rowCount ~=,|dGAa$
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()).uniqueResult(); #)BdN
} hFjXgpz5
}, true); Tx7YHE6{
return count.intValue(); t*)-p:29h
} 1+^L,-k!
} Xx0}KJq~"
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用户在web层构造查询条件detachedCriteria,和可选的 D n?P~%
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 G1"=}Wt`
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PaginationSupport的实例ps。 uv2!][
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ps.getItems()得到已分页好的结果集 4565U
ps.getIndexes()得到分页索引的数组 Cse@>27s
ps.getTotalCount()得到总结果数 %XqLyeOS
ps.getStartIndex()当前分页索引 s.rS06x
ps.getNextIndex()下一页索引 I$neE"wW
ps.getPreviousIndex()上一页索引 oWpy^=D_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 d+|8({X]D8
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 >=2nAv/(
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一下代码重构了。 x
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我把原本我的做法也提供出来供大家讨论吧: dxkXt k
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首先,为了实现分页查询,我封装了一个Page类: MWCP/~>a2
java代码: C<6IiF[>%
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/*Created on 2005-4-14*/ flLC\
package org.flyware.util.page; +MQf2|--
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/** I ,AI$A
* @author Joa 3yXF|
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* &,fBg6A%
*/ Z$,1Tk"O/s
publicclass Page { dox QS ohS
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/** imply if the page has previous page */ }d)>pH
privateboolean hasPrePage; Z\{WBUR;4t
j~"X`: =
/** imply if the page has next page */ $Tq-<FbM)
privateboolean hasNextPage; T.HI
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/** the number of every page */ U$pHfNTH
privateint everyPage; awXL}m[_!
9h$-:y3
/** the total page number */ o"v>
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privateint totalPage; $<]y.nr|CX
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/** the number of current page */ >.#uoW4ZV
privateint currentPage; JPiC/
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/** the begin index of the records by the current yaA9*k
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query */ wLU w'Ai
privateint beginIndex; ^<<( }3
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/** The default constructor */ q!<`ci,uS
public Page(){ R6)p4#|i
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} &tQ,2RT
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/** construct the page by everyPage ,I@4)RSAH|
* @param everyPage }<&g1x'pa
* */ Qkk~{OuC
public Page(int everyPage){ :H\6wJ
this.everyPage = everyPage; z0HCmj9T
} mw`%xID*
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/** The whole constructor */ ` /]8C&u
public Page(boolean hasPrePage, boolean hasNextPage, =X>3C"]
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int everyPage, int totalPage, rP;Fh|w#
int currentPage, int beginIndex){ 3T Q#3h
this.hasPrePage = hasPrePage; ,vW.vq<{q3
this.hasNextPage = hasNextPage; =YZp,{T
this.everyPage = everyPage; Sd^e!?bp
this.totalPage = totalPage; ,h5.Si>
this.currentPage = currentPage; Roy`HU
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this.beginIndex = beginIndex; rQ*'2Zf'<
} JO7IzD\
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/** YT,1E>rd
* @return >H5BY9]I
* Returns the beginIndex. v>)[NAY9
*/ +tkd($//
publicint getBeginIndex(){ m3 (fr
return beginIndex; .K}u`v T
} R.|fc5_"+
g;v{JB
/** DD|%F
* @param beginIndex \(Zdd
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* The beginIndex to set. Si*Pi
*/ GMgsM6.R
publicvoid setBeginIndex(int beginIndex){ d)r=W@tF]
this.beginIndex = beginIndex; \D, 0
} ,`/!0Wmt
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/** lEZ[0oa
* @return RURO0`^
* Returns the currentPage. P!B\:B%4~]
*/ zi[bpa17W
publicint getCurrentPage(){ >eAlz4
return currentPage; LD_aJ^(d
} V)Z*X88:Tv
BIbcm,YQ
/** uTP=kgYqJ
* @param currentPage s4MP!n?gB
* The currentPage to set. +Z$X5Th
*/ !j %)nU
publicvoid setCurrentPage(int currentPage){ @/anJrt
this.currentPage = currentPage; 3'u%[bx
E
} T_jwj
N
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/** 5[X^1
* @return ;5" r)F+P
* Returns the everyPage. ]ueq&|
*/ *[W! ng
publicint getEveryPage(){ 4=F~^Xc`
return everyPage; N;-+)=M,rf
} t}nZrD
IH[/fd0
/** r]BB$^@@V
* @param everyPage :;{U2q+
* The everyPage to set. qdZn9i
*/ #5G!lbH
publicvoid setEveryPage(int everyPage){ y"$|?187x
this.everyPage = everyPage; 3{d1Jk/S
} wzo-V^+q
fRaVY`|wK
/** b%,5B
* @return A{9Hm:)
* Returns the hasNextPage. |%&WYm6
*/ B`RbXk68q
publicboolean getHasNextPage(){ 1/gY]ghL
return hasNextPage; WF *2^iWJ
} OYG8%L
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/** W1r- uR
* @param hasNextPage @U5+1Hjc
* The hasNextPage to set. (M.Sl
*/ RU_=VB %
publicvoid setHasNextPage(boolean hasNextPage){ zMtK_ccQ
this.hasNextPage = hasNextPage; jh\q2E~,`
} HX+'{zm]
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/** _u{D #mmO
* @return 2lAuO!%
* Returns the hasPrePage. GE~mu76%
*/ KQ3)^J_Z
publicboolean getHasPrePage(){ |4X:>Ut]
return hasPrePage; K.l?R#G`,F
} *1; <xeVD
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/** {l *ps-fi
* @param hasPrePage ^>g+:?x
* The hasPrePage to set. y<)Lr}gP
*/ JkQ4'$:
publicvoid setHasPrePage(boolean hasPrePage){ ! ~&X1,l1*
this.hasPrePage = hasPrePage; gA~Ih
} 7:M%w'oR
qx0J}6+NlU
/** 0Lc X7gU>
* @return Returns the totalPage. kz,Nz09}W
* zFB$^)v"<
*/ z<^HohT
publicint getTotalPage(){ tBrd+}e2*
return totalPage; js8uvZ i
} 68 - I2@&
hbE;zY%hP
/** xOTm-Cm9L
* @param totalPage ih ,8'D4
* The totalPage to set. mjBXa
*/ u@|GQXC
publicvoid setTotalPage(int totalPage){ /Pg66H#RUf
this.totalPage = totalPage; 2{+\\.4Evk
} J&8l1{gd
zq{L:.#ha
} VEb}KFyP
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 2&$ A x
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个PageUtil,负责对Page对象进行构造: !^l<jrM
java代码: g%4|vA8
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/*Created on 2005-4-14*/ !8l4Hc8
package org.flyware.util.page; oxcAKo
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import org.apache.commons.logging.Log; 4!/{CGP
import org.apache.commons.logging.LogFactory; A`X$jpAn&
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/** Eg
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* @author Joa 3ufUB^@4v
* 5zfaqt`
*/ KS(s<ip|
publicclass PageUtil { {CQA@p:Y}
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privatestaticfinal Log logger = LogFactory.getLog Rfa1v*(
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(PageUtil.class); YM1@B`yWE
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/** hz\7Z+ $L_
* Use the origin page to create a new page s|EP/=9i
* @param page EkOBI[`
* @param totalRecords p(U'c}@2
* @return nBGk %NM 8
*/
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publicstatic Page createPage(Page page, int
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D}\%
Q #
totalRecords){ ,Y9lp)w
return createPage(page.getEveryPage(), ']}ZI 8
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page.getCurrentPage(), totalRecords); g w}t.3}
} +uv]dD*i
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/** o1I{^7/
* the basic page utils not including exception BS+N
E >SnH
handler 3&3S*1b-H
* @param everyPage ?N $
* @param currentPage ~poy`h'
* @param totalRecords Ov?k4kJ
* @return page mQJRq??P
*/ #XC\=pZX
publicstatic Page createPage(int everyPage, int ">CjnF2>R
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currentPage, int totalRecords){ [gH
vI
everyPage = getEveryPage(everyPage); =<a`G3SY!
currentPage = getCurrentPage(currentPage); W~dS8B=<
int beginIndex = getBeginIndex(everyPage, j6IWdqXe
Et`z7Q*e
currentPage); }@a_x,O/x}
int totalPage = getTotalPage(everyPage, #.FtPR
f4`=yj*
totalRecords); }1d
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boolean hasNextPage = hasNextPage(currentPage, {T m-X`
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totalPage); rf]]I#C7
boolean hasPrePage = hasPrePage(currentPage); oD~VK,.
Sn" 1XU
returnnew Page(hasPrePage, hasNextPage, i(L;1 `
everyPage, totalPage, obaJT"1
currentPage, H$;K(,'
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beginIndex); Wd&!##3$Q
} Ojie.+'SB
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privatestaticint getEveryPage(int everyPage){ K.b-8NIUW
return everyPage == 0 ? 10 : everyPage; ]#R;%L
} DghX(rs_
rDUNA@r
privatestaticint getCurrentPage(int currentPage){ e~nmIy
return currentPage == 0 ? 1 : currentPage; 'S@C,x%2,
} Qmzj1e$6x
>!`T=(u!
privatestaticint getBeginIndex(int everyPage, int /g@.1z1w
OYy %aA}h
currentPage){ %2bZeZ
return(currentPage - 1) * everyPage; J/R=O>
} C x$|7J=O
S-'iOJ1]
privatestaticint getTotalPage(int everyPage, int
MCL5a@BX)
ykX}T6T
totalRecords){ ~A [ Ju%R
int totalPage = 0; }UQBaqDH
[S-NGip
if(totalRecords % everyPage == 0) rv:,Os_
totalPage = totalRecords / everyPage; c?>Q!sC
else d8dREhK&
totalPage = totalRecords / everyPage + 1 ; :eei<cn2
e!G
I<
return totalPage; i&{8a3B
} *sZOws<
Ok2k;
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privatestaticboolean hasPrePage(int currentPage){ D|`[ [
return currentPage == 1 ? false : true; lj'c0k8
} " 0K5
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privatestaticboolean hasNextPage(int currentPage, 5NBc8h7 V
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int totalPage){ { S4?L8
return currentPage == totalPage || totalPage == r?[PIf
'1^\^)&q
0 ? false : true; Q5{i#F7nJm
} {u3^#kF
:}e*3={4
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} .2[>SI
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@
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 I_'vVbK+>
jO<K0cc
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 gWv/3hWWB
p,$1%/m
做法如下: u <D&RT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 WI](a8bm
qW$IpuK
的信息,和一个结果集List: Y'%sA~g
java代码: AX<TkS@wjb
DJ[U^dWRn
}bAd@a9>3
/*Created on 2005-6-13*/ vC&y:XMt,`
package com.adt.bo; nPR_:_^
<P(d%XEl
import java.util.List; cC&R~h]|
DZR kK3
import org.flyware.util.page.Page; HiILJyb
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/** 9)e`mO*n
* @author Joa \,ir]e,1
*/ Y>wpla[kUq
publicclass Result { o5i?|HJ
r-H~MisL
private Page page; E6y/,s^~S_
!ck=\3pr
private List content; Y}(v[QGV
6V*@
{
/** 4US8B=jk
* The default constructor V0c*M>V
*/ 3)EslBA7i
public Result(){ v^HDR 3I
super(); = 14'R4:
} ]J5[ZVz
it D%sKo
/** `i,ZwnLh{
* The constructor using fields KFCuv15w,3
* ORp6
* @param page ZgZ}^x
* @param content .A&Ey5
*/ +2|X 7wA
public Result(Page page, List content){ >"5^]o2?~l
this.page = page; zPH1{|H+l
this.content = content; uy~5!i&
} @@'zMV%
wvp\'* $
/** hc`9Y
* @return Returns the content. C W7E2
^P$
*/ WK:~2m&y
publicList getContent(){ 3@XCP-`
return content; =}Bq"m
} 7.hVbjy'-
S%kE<M?
/** rs=wEMq/
* @return Returns the page. 3!Rb{
*/ 0$":W
public Page getPage(){ ](x4q
return page; G5kM0vs6L
} R^f~aLl
nwOr
/** |hiYV
* @param content +}I[l,,xy
* The content to set. h"
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*/ j/#kO?
public void setContent(List content){ I&q:w\\z8|
this.content = content; [qIi_(%o
} ;]i&AAbj
RR75ke[Hs
/** pIC CjA?3@
* @param page [j
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* The page to set. jF Bq>
*/ bqsb (C
publicvoid setPage(Page page){ ^ Gq2"rDM
this.page = page; *P61q\2Z
} gD@ &/j7
} +r2E5s
f8lB xK
HP3~.1Sp
8rGW G
^h1VCyoR*
2. 编写业务逻辑接口,并实现它(UserManager, N#bWMZ"
/h0-qW
UserManagerImpl) ie
2X.#
java代码: 5w@ ;B
)>\J~{
e,Gv~ae9
/*Created on 2005-7-15*/ G"5Nj3vd
package com.adt.service; 6@]Xwq
Y
H
2iV
import net.sf.hibernate.HibernateException; A AH-Dj|&l
fh b &_T
import org.flyware.util.page.Page; p<Ah50!B
p27A#Uu2}
import com.adt.bo.Result; !6@xX08z
83412@&
/** wf=#w}f
* @author Joa uZ]B ?Z%y#
*/ +LV'E#h!Q
publicinterface UserManager { _ZzN}!Mye
J.$<Lnt>u
public Result listUser(Page page)throws N>/*)Frt
OV7vwj/-
HibernateException; 95T%n{rz
79s6U^vv"
} lE?e1mz{
R`76Ae`R8
q-o=lU"
_a+0LTo".
}(ay(
java代码: p$?c>lim
htX'bA
T5 5l-.>
/*Created on 2005-7-15*/ hX`WVVoF
package com.adt.service.impl; !Ya
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)@]-bPnv
import java.util.List; at,Xad\j
\CUxGyu
import net.sf.hibernate.HibernateException; **_VNDK+
c*RZbE9k
import org.flyware.util.page.Page; Q,#M
0
import org.flyware.util.page.PageUtil; Qc[[@=S%
c`doR(oZ
import com.adt.bo.Result; u8+<uWB
import com.adt.dao.UserDAO; X-:Ni_O\ty
import com.adt.exception.ObjectNotFoundException; puZ<cV
e/
import com.adt.service.UserManager; "'t<R}t!A
4TwU0N+>
/** )6bxP&k
* @author Joa 0qG[hxt%
*/ e!tgWYN
publicclass UserManagerImpl implements UserManager { 5\R8>G~H
xBgf)'W_Z
private UserDAO userDAO; g+ 2SB5 2D
R^1= :<)C
/** +bdkqdB9
* @param userDAO The userDAO to set. ngeX+@
*/ OUI}jJw+
publicvoid setUserDAO(UserDAO userDAO){ 5Hr(9)
this.userDAO = userDAO; /
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} U?$v1 ||
ei\X/Z*q%P
/* (non-Javadoc) B{)Du
:)
* @see com.adt.service.UserManager#listUser 2i,Jnv=sR
wTIf#y1=9
(org.flyware.util.page.Page) }-r"W7]k
*/ nJ*NI)
public Result listUser(Page page)throws ~@'|R%jJ
Z:T4Z}4N
HibernateException, ObjectNotFoundException { Z
NCq/
int totalRecords = userDAO.getUserCount(); p-*BB_J"
if(totalRecords == 0) B2845~\.
throw new ObjectNotFoundException f{3FoN=z
}Ecm
("userNotExist"); 'O{hr0q}
page = PageUtil.createPage(page, totalRecords); PU-~7h+$
List users = userDAO.getUserByPage(page); 0
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returnnew Result(page, users); )s6tjlf8
} L {B#x@9tQ
=602%ef\
} /f# rN_4
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l@j!j]nE
E+~~d6nB
2B!nLLCp+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 $mlsFBd
8\I(a]kM`
询,接下来编写UserDAO的代码: .Bi7~*N
3. UserDAO 和 UserDAOImpl: \ g0
java代码: {|rwIRe
ZT^PL3j+
*-P@|eg
/*Created on 2005-7-15*/ O$&p<~
package com.adt.dao; G 8NSBaZe
.pdgRjlSn
import java.util.List; [fW:%!Y'
MaMs(
import org.flyware.util.page.Page; =%]dk=n?TN
UyF]gO
import net.sf.hibernate.HibernateException; *{-XN
DH9?~|
/** L1D%vu`
* @author Joa fq F1-%
*/ D!@c,H
publicinterface UserDAO extends BaseDAO { LXK+WB/s
T
7
hC]R
publicList getUserByName(String name)throws 5,mb]v0k
5 TnECk
HibernateException; i\t4TdEx(
#K4wO!d
publicint getUserCount()throws HibernateException; L~0B
T
%cN(0@
publicList getUserByPage(Page page)throws
Ng-3|N
Zd5frc$
HibernateException; \,_%e[g49
Y)a 7osML
} Z+vLEEX*uQ
Y)!5Z.K
#cmj?y()
xUeLX`73
k@wxN!w;
java代码: ~5JXY5*o
yt<K!=7&
9pk<=F
/*Created on 2005-7-15*/ Uh9$e
package com.adt.dao.impl; Tlf G"HzZ%
M<)HJ lr
import java.util.List; gGZ$}vX
fYH%vr)
import org.flyware.util.page.Page; fo5!d@Nv
ikofJl]9
import net.sf.hibernate.HibernateException; z}pdcQl#
import net.sf.hibernate.Query; l9SbuT$U
J[<:-$E
import com.adt.dao.UserDAO; \Mi y+<8$
9 s>JdAw?
/**
XLzHm&;
* @author Joa IJs`3?
*/ 0_%u(?
public class UserDAOImpl extends BaseDAOHibernateImpl Dpof~o,f
^Ji5)c
implements UserDAO { %+`$Lb?{
cQN}z
Ke
/* (non-Javadoc) ;up89a-,9
* @see com.adt.dao.UserDAO#getUserByName @y}1%{,%
R[Pyrs!H
(java.lang.String) q,+d\-+
*/ _STN ^
publicList getUserByName(String name)throws P/0n)
Q
j4Lf6aUOX
HibernateException { y=q\1~] Z
String querySentence = "FROM user in class )TV'eq
QDyL0l{C
com.adt.po.User WHERE user.name=:name"; nC2A&n