Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d>fkA0G/9!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?_vakJ
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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 DN~nk
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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 V(6Z3g
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分页支持类: bc)~k:
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java代码: /!$c/QZ
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package com.javaeye.common.util; /bi[e9R
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import java.util.List; Q/_f
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publicclass PaginationSupport { DhT>']Z
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publicfinalstaticint PAGESIZE = 30; ie\"$i.98H
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privateint pageSize = PAGESIZE; *ikc]wQr$
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privateList items; af+IP_6
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privateint totalCount; .#Z%1U%P.
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privateint[] indexes = newint[0]; Rh{zH~oZ
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privateint startIndex = 0; Vle@4]M\
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public PaginationSupport(List items, int d%,eZXg'
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totalCount){ tj4VWJK
setPageSize(PAGESIZE); U($dx.`v#
setTotalCount(totalCount); {(wHPzq
setItems(items); ac.Ms (D
setStartIndex(0); pxf$1
} W"'iIh)z
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public PaginationSupport(List items, int lM{
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totalCount, int startIndex){ &8_gRP
setPageSize(PAGESIZE); 1ilBz9x*!
setTotalCount(totalCount); ;Q[mL(1:
setItems(items); Upd3-2kr&J
setStartIndex(startIndex); z3M6V}s4
} w1"nffhO
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public PaginationSupport(List items, int *B{j.{
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totalCount, int pageSize, int startIndex){ Jesjtcy<*
setPageSize(pageSize); [P7N{l=I
setTotalCount(totalCount); &2zq%((r
setItems(items); +0q>fp_K(+
setStartIndex(startIndex); e\JojaV
} R>"OXFaE
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publicList getItems(){ Kt|1&Gk
return items; /_Z652@
} K7Wk6Aw
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publicvoid setItems(List items){ .0O2Qqdg
this.items = items; F[[TWf/
} GF%314Xu
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publicint getPageSize(){ D{d>5P?W
return pageSize; HnCzbt@
} m"jV}@agX
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publicvoid setPageSize(int pageSize){ -3lb@ 6I6
this.pageSize = pageSize; 5
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} ?Ovqp-sw
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publicint getTotalCount(){ 5N*Ux4M
return totalCount; uDSxTz{
} wqW0v\
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publicvoid setTotalCount(int totalCount){ )}'U`'q
if(totalCount > 0){ | j a-
this.totalCount = totalCount; i?:_:"^x
int count = totalCount / R@#G>4
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pageSize; w MP
if(totalCount % pageSize > 0) ' dx1x6
count++; nn9wdt@.]
indexes = newint[count]; &0(
for(int i = 0; i < count; i++){ [.*;6y3
indexes = pageSize * f'{]"^e=
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i; !o+_T?
} ]mXLg:3B
}else{ L%c0 Z@[~
this.totalCount = 0; b2=0}~LK
} *"r~-&IL
} <rL/B
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publicint[] getIndexes(){ S&Ee,((E(
return indexes; h=_0+\%
} v\"S
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publicvoid setIndexes(int[] indexes){ 0{PzUIM,W
this.indexes = indexes; =)`
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} t2iv(swTe
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publicint getStartIndex(){ yxq}QSb \3
return startIndex; ZzBQe
} STw#lU) %(
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publicvoid setStartIndex(int startIndex){ FwZ>{~?3
if(totalCount <= 0) ~/ilx#d
this.startIndex = 0; ^F"iP7
elseif(startIndex >= totalCount) D.6,VY H
this.startIndex = indexes -+em!g'
l-$uHHyu*
[indexes.length - 1]; hy T1xa
elseif(startIndex < 0) \VFHHi:I
this.startIndex = 0; W|,V50K
else{ W$Yc'E
;
this.startIndex = indexes Pv+5K*"7Cg
)&<=.q
[startIndex / pageSize]; w7n373y%
} y tf b$;|
} D'hW|
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publicint getNextIndex(){ !GQ\"Ufs>
int nextIndex = getStartIndex() + vuFBET,
H7kPM[
pageSize; A?T<",bO
if(nextIndex >= totalCount) FsGlJ
return getStartIndex(); 9A7@
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else !!nuAQ"E[
return nextIndex; h<\_XJJ
} H<G4O02i_
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publicint getPreviousIndex(){ ,mL
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int previousIndex = getStartIndex() - k%op>
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pageSize; !;!~n`
if(previousIndex < 0) b2b75}_A
return0; `g1iCF
else Y05P'Q
return previousIndex; cbu@*NzY,
} *VkgQ`c
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} 5I@w~z
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抽象业务类 [|3>MZ2/
java代码: 92'wkS
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/** Px>va01n
* Created on 2005-7-12 Q9`QL3LQD
*/ a%Jx
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package com.javaeye.common.business; 35*\_9/#
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import java.io.Serializable; WWZ9._
import java.util.List; VNtPKtx\
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import org.hibernate.Criteria; {3Vk p5%l
import org.hibernate.HibernateException; U\?g*
import org.hibernate.Session; w_iam qe,
import org.hibernate.criterion.DetachedCriteria; CC3v%^81l^
import org.hibernate.criterion.Projections; T^}
import X+n`qiwq
RP`2)/sMT
org.springframework.orm.hibernate3.HibernateCallback; \ M/6m^zS
import $,hwU3RVxc
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org.springframework.orm.hibernate3.support.HibernateDaoS l~Lb!; ,dN
J%]D%2vnk`
upport; ^5 t
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import com.javaeye.common.util.PaginationSupport; Ab1/.~^
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public abstract class AbstractManager extends e|r0zw S
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HibernateDaoSupport { i
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privateboolean cacheQueries = false; m!OMrZ%)}
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privateString queryCacheRegion; bxXiQa
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publicvoid setCacheQueries(boolean jec:i-,
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cacheQueries){ 2PSTGG8JV
this.cacheQueries = cacheQueries; 7>
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} hD<f3_k
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publicvoid setQueryCacheRegion(String ~mN%(w!^
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queryCacheRegion){ ]PNowS\
this.queryCacheRegion = <Jp1A#
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queryCacheRegion; C6&( c
} H%z@h~s>
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publicvoid save(finalObject entity){ ER{3,0U
getHibernateTemplate().save(entity); DjW$?>
} - &[z\"T
;</Twm;:
publicvoid persist(finalObject entity){ (w2=
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getHibernateTemplate().save(entity); wX'}4Z=C~
} $rG<uO
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publicvoid update(finalObject entity){ 2#_38=K=@
getHibernateTemplate().update(entity); czBi Dk4
} ]5v:5:H
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publicvoid delete(finalObject entity){ r[Zq3
getHibernateTemplate().delete(entity); S9Yt 1qb
} 3#<*k>1G?
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publicObject load(finalClass entity, %>XN%t'6aT
| D.C!/69
finalSerializable id){ hWcTI{v
return getHibernateTemplate().load I/UQ' xx
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(entity, id); CM~MoV[k7e
} LI:Tc7t
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publicObject get(finalClass entity, hE!7RM+Y
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finalSerializable id){ g<[rH%\6fg
return getHibernateTemplate().get dA#{Cn;
$ehg@WK}.
(entity, id); F$hZRZ
} Ud3""C5B
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publicList findAll(finalClass entity){ FUaNiAr[
return getHibernateTemplate().find("from _JOP[KHb
+*t|yKO>[
" + entity.getName()); TV{)n'aA
} Z%v6xP.
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publicList findByNamedQuery(finalString vg5NY =O
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namedQuery){ E5B8 Z?$a
return getHibernateTemplate H(\V+@~>AD
}#b
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().findByNamedQuery(namedQuery); b4~H3|
} If}lJ6jZ
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publicList findByNamedQuery(finalString query, KP~-$NR
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finalObject parameter){ &jJckT
return getHibernateTemplate [b5(XIGUN}
t]TyXAr~
().findByNamedQuery(query, parameter); )DZTB
} pVOI5>f\
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publicList findByNamedQuery(finalString query, ,ZK]i CGk
/{G/|a
finalObject[] parameters){ YhgUCF#
return getHibernateTemplate (G5xkygR9
OKQLv+q5K)
().findByNamedQuery(query, parameters); KF{a$d
} `45d"B
I
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publicList find(finalString query){ t&"5dM\
return getHibernateTemplate().find RWahsJTu
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(query); HtzMDGV<
} qWB%),`j>
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publicList find(finalString query, finalObject Jn,w)Els
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parameter){ h3h8lt_|
return getHibernateTemplate().find P{lh)m>
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(query, parameter); kukaim>K
} d8.ajeN]o
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public PaginationSupport findPageByCriteria Z1]"[U[;
q)Je.6$#X
(final DetachedCriteria detachedCriteria){ \UtS>4w\
return findPageByCriteria l%bq2,-%
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); eG^z*`**
} /'Bdq?!B&
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public PaginationSupport findPageByCriteria s?<!&Y
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(final DetachedCriteria detachedCriteria, finalint dP3VJ3+
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startIndex){ oUS,+e
return findPageByCriteria 8OBF^r44R
g*r/u;
(detachedCriteria, PaginationSupport.PAGESIZE, W]~ZkQ|P
2;R/.xI6v
startIndex); W^ClHQ"Iy
} `1_FQnm)
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public PaginationSupport findPageByCriteria D'?]yyrf
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(final DetachedCriteria detachedCriteria, finalint 0nT%Slbih
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pageSize, b.(XS?4o
finalint startIndex){ T]X{@_
return(PaginationSupport) 2HVCXegq
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getHibernateTemplate().execute(new HibernateCallback(){ Wbs^(iUU}
publicObject doInHibernate 9!S^^;PN&
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(Session session)throws HibernateException { d5q4'6o,
Criteria criteria = vK`S!7x'&
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detachedCriteria.getExecutableCriteria(session); Qf~| S9,
int totalCount = \y,;Cfl<
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((Integer) criteria.setProjection(Projections.rowCount ,@,LD u
/W``LK>;?
()).uniqueResult()).intValue(); }*ODM6
criteria.setProjection 4Q/r[x/&C
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(null); I &cX8Tw
List items = Cd9t{pQD4
C*]AL/
criteria.setFirstResult(startIndex).setMaxResults n\
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(pageSize).list(); 5GUH;o1m
PaginationSupport ps = wz)m{:b<
$;ch82UiX
new PaginationSupport(items, totalCount, pageSize, H WOek"}Z[
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startIndex); \cFAxL(
return ps; i~ROQMN1
} taBO4LV
}, true); 3lyQn"
} @#1cx
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public List findAllByCriteria(final {Wr\DVp
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DetachedCriteria detachedCriteria){ (J/>Gy)d
return(List) getHibernateTemplate d[yrNB6|
r \9:<i8
().execute(new HibernateCallback(){ cy9N:MR(c
publicObject doInHibernate cyDiA(ot&
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(Session session)throws HibernateException { M$gvq:}kt
Criteria criteria = # e$\~c Pd
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detachedCriteria.getExecutableCriteria(session); ^v#+PyW
return criteria.list(); 2}ag_
} Lq3(Z%
}, true); M2a}x+5'
} dzpj9[
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public int getCountByCriteria(final |F3vRt@
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DetachedCriteria detachedCriteria){ |c]> Q
Integer count = (Integer) 2c!h2$w
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate 4b]IazL)
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(Session session)throws HibernateException { gjO
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Criteria criteria = wYC9~ms-
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detachedCriteria.getExecutableCriteria(session); u;$I{b@M]
return e1:u1(".
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criteria.setProjection(Projections.rowCount _QD/!~O
;&/sj-xJ2
()).uniqueResult(); [))gn
} aS3P(s L
}, true); &f$a1#O}dx
return count.intValue(); lF)0aDk'h
} ojiM2QT}m
} BYTXAZLb
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用户在web层构造查询条件detachedCriteria,和可选的 F%w\D9+P
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 e-&L\M
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PaginationSupport的实例ps。 9)8*FahW
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ps.getItems()得到已分页好的结果集 wn&[1gBxM
ps.getIndexes()得到分页索引的数组 DX]z=d)tc
ps.getTotalCount()得到总结果数 4da^d9ZOy
ps.getStartIndex()当前分页索引 cYBrRTrI#
ps.getNextIndex()下一页索引 bkJwP s
ps.getPreviousIndex()上一页索引 hhN(;.
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F Bd+=bx,Z
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 O e0KAn
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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 w@<<zItSo
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一下代码重构了。 ][s*~VK;
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我把原本我的做法也提供出来供大家讨论吧: !pE>O-| K
q8&4=eV\A
首先,为了实现分页查询,我封装了一个Page类: |:`?A3^m#
java代码: UHTb61Gs
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/*Created on 2005-4-14*/ V>~*]N^f
package org.flyware.util.page; q>Dr)x)
roK4RYJ7)
/** MVu[gB
* @author Joa <v1_F;{n
* EBN]>zz
*/ C.B8 J"T-
publicclass Page { =|DkD-
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/** imply if the page has previous page */ ^hGZVGSv
privateboolean hasPrePage; LNsE7t
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/** imply if the page has next page */ ur,V>J<5A
privateboolean hasNextPage; gK] T}
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/** the number of every page */ \oD=X}UQw(
privateint everyPage; x3:ZB
#,Fx@3y\a
/** the total page number */ Lx4H/[$6D
privateint totalPage; l,~ N~?
# UP,;W
/** the number of current page */ b*$o[wO9
privateint currentPage; .pNq-T
&**.naSo
/** the begin index of the records by the current i&AXPq>`
jb6ZAT<8
query */ 06j)P6Iju
privateint beginIndex; DVeF(Y3&
@Reh?]# v
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/** The default constructor */ j:\_*f
public Page(){ =qVAvo'
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} bN<O<x1j
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/** construct the page by everyPage \f<thd*bC
* @param everyPage *axza~d
* */ =#PudF.\
public Page(int everyPage){ a*e|>p DO
this.everyPage = everyPage;
t}* qs
} QvyUd%e'5A
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/** The whole constructor */ :;#c:RKi:
public Page(boolean hasPrePage, boolean hasNextPage, ' ]H#0.
+LU ).
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int everyPage, int totalPage, LXOF{FG
int currentPage, int beginIndex){ & t @
this.hasPrePage = hasPrePage; `04Y ;@w
this.hasNextPage = hasNextPage; '~!l(&X
this.everyPage = everyPage; q0xE&[C[M
this.totalPage = totalPage; 0v,`P4_k
this.currentPage = currentPage; R?FtncL%D
this.beginIndex = beginIndex; !{|yAt9kP
} N'q/7jOy
*?
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/** :O_<K&
* @return Yru1@/;
* Returns the beginIndex. #0$eTdx#
*/ P St|!GST
publicint getBeginIndex(){ TBLk+AR
return beginIndex; I "+|cFq.
} m'vOFP)'
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/** EXScqGa]
* @param beginIndex OYCFx2{
* The beginIndex to set. ,4?|}xg
*/ hJL0M!
publicvoid setBeginIndex(int beginIndex){ EJiF_
this.beginIndex = beginIndex; U#^:f7-$.
} :8/M6-EK
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/** \c`r9H^v{
* @return Z6HkQ=A64
* Returns the currentPage. . KSr@Gz
*/ 5&7?0h+I
publicint getCurrentPage(){ $y |6<
return currentPage; g\mrRZ/?
} 1=cfk#
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/** gB'Ah -@,P
* @param currentPage OA5md9P;d
* The currentPage to set. T;vPR,]rz
*/ &JzF
publicvoid setCurrentPage(int currentPage){ k>@^M]%
this.currentPage = currentPage; MyS7AL
} 'c\TMb.
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/** H0Gp mKYW
* @return "7u"d4h-:(
* Returns the everyPage. H@bmLq
*/ TuhL:
publicint getEveryPage(){ n"VE!`B
return everyPage; ;@UX7NA
} x>/@Z6Wxz
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/** Yka yT0!
* @param everyPage <EE+
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* The everyPage to set. 4% .2=
*/ lbXkZ ,
publicvoid setEveryPage(int everyPage){ Z.#glmw^=R
this.everyPage = everyPage; G"R>a w
} `x^,k%
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/** i /U{dzZ
* @return t
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* Returns the hasNextPage. $@!&ML
*/ ?^A:~" ~
publicboolean getHasNextPage(){ ,lG wW8$R
return hasNextPage;
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} ;eSf4_~
U@ QU8
/** 4BL,/(W]
x
* @param hasNextPage h 7P?n.K
* The hasNextPage to set. +as\>"Cj+2
*/ fv7g93
publicvoid setHasNextPage(boolean hasNextPage){ D,R2wNF
this.hasNextPage = hasNextPage; Hu!>RSg,,2
} 7)X&fV6<8
Q`fA)6U
/** Bc,z]
* @return !6`nN1A
* Returns the hasPrePage. dK`O,[}
*/ ?26[%%
publicboolean getHasPrePage(){ 3cQmxp2*
return hasPrePage; EJ|ZZYke!
} !ZcALtq
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/** 4o8HEq!
* @param hasPrePage M L_J<|,J
* The hasPrePage to set. ;SP3nU))
*/ ZQ8Aak
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; 5rSth.&
} 0-O.*Q^
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/** \O4=mJ
* @return Returns the totalPage. s,q!(\{Pv
* R^C;D2
*/ 8+b3u05
publicint getTotalPage(){ R')GQ.yYq
return totalPage; +*~3"ww<
} 87*[o
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e
/** f
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* @param totalPage ?Qp_4<(5
* The totalPage to set. nUu|}11 (
*/ , |B\[0p
publicvoid setTotalPage(int totalPage){ oW9rl]+
this.totalPage = totalPage; "qp_*Y
} 89dC
bF3b
AH,F[vS
} :Bc;.%
! (tJZ5
+\m!#CSA
eW<hC(
4s2ex{$+MA
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 L{Zy7O]"d
f%l#g ]]
个PageUtil,负责对Page对象进行构造: D1/$pA+B
java代码: ^(B*AE.
j<5R$^?U
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/*Created on 2005-4-14*/ \OB3gnR
package org.flyware.util.page; 6g&nnA
\Ki#"%S
import org.apache.commons.logging.Log; [K QZHIe
import org.apache.commons.logging.LogFactory; .U
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/** rrq-so1u}
* @author Joa 'D{abm0
* Q)8t;Kx
*/ 7 4UE-H)
publicclass PageUtil { XcneH jpR
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7x
privatestaticfinal Log logger = LogFactory.getLog PUArKBYM-
1(a\$Di
(PageUtil.class); 8h2?Q
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/** "+_0idpF
* Use the origin page to create a new page tx-bzLo\
* @param page osI(g'Xb
* @param totalRecords )2hoO_l:
* @return wkw/AZ{27
*/ D.f=!rT7E7
publicstatic Page createPage(Page page, int wxrT(x|
Reo0ZU>
totalRecords){ wtyu"=
return createPage(page.getEveryPage(), e2F7G>q:5
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page.getCurrentPage(), totalRecords); @x4Dt&:"
} E$
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W ,+91rup
/** Q0q$ZK6C
* the basic page utils not including exception 0:p#%Nvg
W=:+f)D
handler } U.B$4Q
* @param everyPage L1BpY-=
* @param currentPage 'z:p8"h}
* @param totalRecords b.+\qaR
* @return page #U6qM(J
*/ mYvm_t9
publicstatic Page createPage(int everyPage, int <hdCO<
0(
*WG}K?"/
currentPage, int totalRecords){ <NO~TBHF
everyPage = getEveryPage(everyPage); +f+yh0Dj
currentPage = getCurrentPage(currentPage); MN4}y5
int beginIndex = getBeginIndex(everyPage, \h4y,sl
*qBZi;1
currentPage); K<(RVh
int totalPage = getTotalPage(everyPage, [OSUARm
v
4 vphLAm
totalRecords); i:72FVo
boolean hasNextPage = hasNextPage(currentPage, 8!fwXm
,5,4 Qf7
totalPage); 0XNb@ogo
boolean hasPrePage = hasPrePage(currentPage); &2J|v#$F
V"XN(Fd^
returnnew Page(hasPrePage, hasNextPage, YoA$Gw2
everyPage, totalPage, P8f-&(
currentPage, Pe.D[]S
We2=|AB
beginIndex); ZWH`s
} Ns_d10rZ.
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privatestaticint getEveryPage(int everyPage){ YzqhFFaj.
return everyPage == 0 ? 10 : everyPage; V
Euv
}
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Z)~2{)
privatestaticint getCurrentPage(int currentPage){ Z "u/8
return currentPage == 0 ? 1 : currentPage; CDhk!O..
} Yc}b&
v.MWO]L
privatestaticint getBeginIndex(int everyPage, int 4m:E:zVn
vbp)/I-h
currentPage){ $6N.ykJ
return(currentPage - 1) * everyPage; ;uy/Vc5,Y
} \=JKeL|6[S
'
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privatestaticint getTotalPage(int everyPage, int R0WJdW#
"d'@IN
totalRecords){ >8Y >B)
int totalPage = 0; B4C`3@a
$Fj7'@1(
if(totalRecords % everyPage == 0) dj#<,e\
totalPage = totalRecords / everyPage; o<y7Ut
else gd*\,P
totalPage = totalRecords / everyPage + 1 ; lz>hP
827N?pU$)
return totalPage; |8"HTBb\CW
} ofJ@\xS
2rk_ ssvs
privatestaticboolean hasPrePage(int currentPage){ z3,z&Ra
return currentPage == 1 ? false : true; %PpB$
} %/7`G-a.B
B^
h!F8DC
privatestaticboolean hasNextPage(int currentPage, P06K0Fxf
yI!K
quMC
int totalPage){ " 1Bn/Q
return currentPage == totalPage || totalPage == Q_Rr5/
Oo E@30+
0 ? false : true; eL.S="
} J
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d 9|u~3
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} R!O'DM+
d;z`xy(C
8m iIlB
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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。 TUT>*
E?V:dr
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 ^>>Naid
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做法如下: <H.Ml>q:r
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Z1&8U=pax
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的信息,和一个结果集List:
d%<Uh(+:
java代码: W\"cp[b
E4PP&'
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/*Created on 2005-6-13*/ Gh j[nsoC~
package com.adt.bo; /2c?+04+
^;'3(m=
import java.util.List; n`6vM4rM)
v^vEaB
import org.flyware.util.page.Page; )gE:@3
5i0<BZDTef
/** bAgKOfT
* @author Joa q
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*/ GYBM]mW^ W
publicclass Result { {YkW5zC(L
[bAv|;
private Page page; m2_B(-
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private List content; (t <Um
Vd
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/** nD!^0?
* The default constructor ZEB1()GB
*/ IgVxWh#
public Result(){ ^OUkFH;dG?
super(); Vry#
} `=oN &!
M$w^g8F27H
/** aw(P@9]
* The constructor using fields DY1o!thz)
* bygwoZ<E
* @param page "UE'dWz
* @param content UXd\Q''
*/ pJ{sBp_$
public Result(Page page, List content){ _rSnp
this.page = page; )%*uMuF
this.content = content;
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} sYvO"|
mFT[[Z#
/** uvT]MgT
* @return Returns the content. l?ofr*U&-x
*/ *p
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publicList getContent(){ I`
/'\cU9
return content; ~(}zp<e|
} +_+}^Nf]Y3
R!:1{1
/** x
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* @return Returns the page. .*8.{n5
*/ na <g
/&
public Page getPage(){ 8G9V8hS1#B
return page; BH=vI<D
} eI- ~ +.
$L?stgU
/** <#:"vnm$j
* @param content Y1+f(Q
* The content to set. WO]dWO6Mm
*/ m~#O
~)
public void setContent(List content){ zp d4uto5
this.content = content; A\WgtM
} %6 Bt%H
++xEMP)
/** Rf7py )
* @param page D>05F,a
* The page to set. *K!V$8k=99
*/ Q&yfl
publicvoid setPage(Page page){ ns@b0'IF]
this.page = page; "",V\m
} -8g ;t3z
} qW),)i
*2@Ne[dYEF
g!4"3Dtdg
\ B<(9
lepgmQ|oY
2. 编写业务逻辑接口,并实现它(UserManager, R(3V !ph
K5b8lc
UserManagerImpl) %T!UEl`v
java代码: ]kR 93
Yk[yG;W
iugTXZ(
/*Created on 2005-7-15*/ JTrxh]
package com.adt.service; B\9ymhx;g%
jRzR`>5
import net.sf.hibernate.HibernateException; 0/;T\9
9J*m!-hOY
import org.flyware.util.page.Page; (Zx;GS
6dV92:
import com.adt.bo.Result; Es1Yx\/:
}wz )"
/** zS]Yd9;X1
* @author Joa B$aboL2
*/
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publicinterface UserManager { UEt#;e
u
JGYXlLE
public Result listUser(Page page)throws }Z"<KF
^2XoYgv
HibernateException; &H<-joZ)Z\
ewD61Y8-
} "C%;9_ig$
FX 0^I 0
n~k;9`
(yn!~El3
L3'o2@$
java代码: IKH#[jW'IB
5Tkh6 s
=]E;wWC
/*Created on 2005-7-15*/ j?#S M!f
package com.adt.service.impl; 8g^OXZ
c(i-~_
import java.util.List; s9zdg"c'
0O|T\E8e
import net.sf.hibernate.HibernateException; I"y=A7Nq
OiZPL" Q(K
import org.flyware.util.page.Page; -(@dMY
import org.flyware.util.page.PageUtil; "EDn;l-Q
p~En~?<
import com.adt.bo.Result; 3T%WfS+
import com.adt.dao.UserDAO; aa8WRf
import com.adt.exception.ObjectNotFoundException; }r9f}yX9Q
import com.adt.service.UserManager; 3;@t{rIin
6(VCQ{
/** ;VNwx(1l`
* @author Joa W_ngB[
*/ ^;!A`t
publicclass UserManagerImpl implements UserManager { G/bWn@
5,|^4
ZA
private UserDAO userDAO; JO1KkIV
:TxfkicN\
/** M8Q-x-7
* @param userDAO The userDAO to set. dt<PZ.
*/ [wi "
publicvoid setUserDAO(UserDAO userDAO){ v_En9~e^n
this.userDAO = userDAO; o
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} 1B}6 zJ
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/* (non-Javadoc) @I_A\ U{
* @see com.adt.service.UserManager#listUser J#!:Z8b
eOE7A'X
(org.flyware.util.page.Page) P
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*/ ?x%HQ2`
public Result listUser(Page page)throws 1.]#FJe
R4%!W~K
HibernateException, ObjectNotFoundException { &1{RuV&t
int totalRecords = userDAO.getUserCount(); 4hr;k0sD
if(totalRecords == 0) #swzZyM$
throw new ObjectNotFoundException ,g;~:
,yNPD}@v>
("userNotExist"); .yd{7Te
page = PageUtil.createPage(page, totalRecords); dyC: Mko=
List users = userDAO.getUserByPage(page); EL;Ir tU
returnnew Result(page, users); nxA Y]Q
} Z;P[)q
/#GX4&z
} 'RC(ss1G
=;9Wh!{
Y7zg
s0~a5Ti3
r=~yUT
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 kVCSFF*
|[)t4A"}
询,接下来编写UserDAO的代码: =hH>]$J[
3. UserDAO 和 UserDAOImpl: kS%FV;9>(
java代码: G29PdmY$<
O$V
6QJ
@(,k%84z
/*Created on 2005-7-15*/ s=!
y%
package com.adt.dao; 'p80X^g
7%c9 nY
import java.util.List; #KF:(2
*RD9gIze
import org.flyware.util.page.Page; dP=1*
}5z6b>EI9a
import net.sf.hibernate.HibernateException; - /]ro8V$
.9#4qoM'
/** xa[<k>r3
* @author Joa (_^g:>)Cs
*/ hc4<`W{
publicinterface UserDAO extends BaseDAO { b'p bf
RFU(wek
publicList getUserByName(String name)throws YR@@:n'TP
V7G?i\>
HibernateException; :z_D?UQ
EW%%W6O6
publicint getUserCount()throws HibernateException; s/Fc7V!;
;]D@KxO$dJ
publicList getUserByPage(Page page)throws Py^F},?J
+y! dU{L^
HibernateException; iW(HOsA
gYn1-/Z>I
} Ol`/r@s
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2asA]sY
Ok/~E
3ZGU?Z;R
java代码: EDcR:Dw3
`Rub"zM
)mz [2Sfg
/*Created on 2005-7-15*/ d kHcG&)
package com.adt.dao.impl; BNw^ _j1
16 _HO%v->
import java.util.List; v`A^6)U#M
o7i/~JkTP
import org.flyware.util.page.Page; QZ$94XLI
S7N3L."
import net.sf.hibernate.HibernateException; Qw!cd-zc
import net.sf.hibernate.Query;
({zt=}r,
8xJdK'
import com.adt.dao.UserDAO; #O6SEK|Z
@>,3l;\Zh
/** yv=LT~
* @author Joa LyH8T'C~
*/ p%EU,:I6
public class UserDAOImpl extends BaseDAOHibernateImpl .Qg!_C
kSv?p1\@&P
implements UserDAO { $qYtN`b,
d/!sHr69
/* (non-Javadoc) "IA[;+_"
* @see com.adt.dao.UserDAO#getUserByName
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sesr`,m.,
(java.lang.String) :~3sW< PR
*/ 1k6f|Al-
publicList getUserByName(String name)throws Wp/!;
*[*LtyCQt4
HibernateException { R/R[r> 1)6
String querySentence = "FROM user in class \[Op:^S
Vy.A`Hz
com.adt.po.User WHERE user.name=:name"; gV1&b
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Query query = getSession().createQuery 4-^|e
.'mmn5E
(querySentence); $)\%i =
query.setParameter("name", name); vmK<_xbwd
return query.list(); @+h2R
} I~\j%zD
bAms-cXm
/* (non-Javadoc) 5\8Ig f>
* @see com.adt.dao.UserDAO#getUserCount() H_sLviYLu
*/ {>tgNW>)
publicint getUserCount()throws HibernateException { h@=H7oV7k
int count = 0; 1dh_"/
String querySentence = "SELECT count(*) FROM d|k6#f-E
BoYWx^VHx^
user in class com.adt.po.User"; 'uBXSP#
Query query = getSession().createQuery ny%-u&1k
7m_Jb5
(querySentence); ;Xg6'yxJ
count = ((Integer)query.iterate().next G,9osTt/
4SCb9|/Q
()).intValue(); yS p]+
return count; 5<w"iqZ\?N
} uNZJNrV%
wvvMesX<L
/* (non-Javadoc) }WS%nQA
* @see com.adt.dao.UserDAO#getUserByPage fqZqPcT0
hAi50q;z
(org.flyware.util.page.Page) )[yM4QFl
*/ u6IEBYG ((
publicList getUserByPage(Page page)throws \!j{&cJ
S9d+#6rn
HibernateException { ugcWFB5|
String querySentence = "FROM user in class A1e| Y
(`x6QiG!
com.adt.po.User"; ZfM(%rx
Query query = getSession().createQuery y5B4t6M(
v/=O:SM}
(querySentence); jCqs^`-
query.setFirstResult(page.getBeginIndex()) _;3xG0+
.setMaxResults(page.getEveryPage()); "]>JtK
return query.list(); 9Xo'U;J
} V^B'T]s
U4qp?g+:
} Z2~;u[0a[
,pE{N&p9
Zm& X $U
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^]o]'
至此,一个完整的分页程序完成。前台的只需要调用 ~F~g$E2 }
"gjy+eosY
userManager.listUser(page)即可得到一个Page对象和结果集对象 cJj4qXF
g+;m?VJ
的综合体,而传入的参数page对象则可以由前台传入,如果用 '
Z:FGSwT
F?&n5