Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +%>:0mT
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bKVj [r8D~
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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 WKM)*@#,
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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 8ovM\9qT
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。 {QaNAR=)
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分页支持类: H!IshZfktn
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java代码: LE^G&<!
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package com.javaeye.common.util; SkNre$>t{
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import java.util.List; 1^J`1
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publicclass PaginationSupport { ^)yTBn,
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publicfinalstaticint PAGESIZE = 30; yBed kj
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privateint pageSize = PAGESIZE; ;;s* Ohh
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privateList items; Y(VJbm`
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privateint totalCount; B6P|Z%E;D6
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privateint[] indexes = newint[0]; aT l c
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privateint startIndex = 0; ks;%*d
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public PaginationSupport(List items, int \$*$='6"
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totalCount){ XEM'}+d
setPageSize(PAGESIZE); vH%gdpxX
setTotalCount(totalCount); `\|ssC8u
setItems(items); ov#7hxe
setStartIndex(0); qk(P>q8[
} g+8hp@a
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public PaginationSupport(List items, int ,.IEDF<&
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totalCount, int startIndex){ .S\&L-{
setPageSize(PAGESIZE);
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setTotalCount(totalCount); JOnyrks
setItems(items); 4JIYbb-a'
setStartIndex(startIndex); lG<hlYckv
} I,6/21kO
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public PaginationSupport(List items, int cTZ.}eLh
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totalCount, int pageSize, int startIndex){ Tsb{25`+
setPageSize(pageSize); Br>Fpe$q4
setTotalCount(totalCount); u~zs*
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setItems(items); lb'Cl 3H
setStartIndex(startIndex); `'_m\uo
} 7\
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publicList getItems(){ 4pz|1Hw7
return items; }A$WO{2
} s Wjy6;
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publicvoid setItems(List items){ ewsKH\#
this.items = items; ]LPQYL
} cFd
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publicint getPageSize(){ `ejUs]SR
return pageSize; v`q\6i[-
} XkKC!
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publicvoid setPageSize(int pageSize){ wt}9B[
this.pageSize = pageSize; o6kNx>tc)
} hmbj*8
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publicint getTotalCount(){ 1{"llD
return totalCount; CENVp"C/`
} lVH<lp_ZtK
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publicvoid setTotalCount(int totalCount){ pj|pcv^
if(totalCount > 0){ Q'B6^%:<~
this.totalCount = totalCount; ?@6b>='!
int count = totalCount / q(^Q3
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pageSize; c/W=$3
if(totalCount % pageSize > 0) RWq{Ff}Hk
count++; /G{_7cb
indexes = newint[count]; Jwn AW}=
for(int i = 0; i < count; i++){ f6<g3Q7Mu
indexes = pageSize * U4?(A@z9^
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i; $9
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} &(rWw Oo6
}else{ ri~<~oB2:
this.totalCount = 0; 1r[@(c0
} )QKf7 [:
} {C*\O)Gep
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publicint[] getIndexes(){ 6&v?)o
return indexes; }`_@'4:t
} 0O!cN_l|
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publicvoid setIndexes(int[] indexes){ o(A|)c4k
this.indexes = indexes; ;bu#8,
} T0HuqJty
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publicint getStartIndex(){ sE(HZR1
return startIndex; 8Ad606
} %6j)=IOts
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publicvoid setStartIndex(int startIndex){ 4NEq$t$Jn
if(totalCount <= 0) Z*{]
,
this.startIndex = 0;
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elseif(startIndex >= totalCount) YL^=t^!4
this.startIndex = indexes -!qu"A:
pz^<\
[indexes.length - 1]; XP[uF ;w
elseif(startIndex < 0) K5Wg"^AHY/
this.startIndex = 0; I lR\
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else{ ?gGt2O1J
this.startIndex = indexes yQS+P8x&|]
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[startIndex / pageSize]; EER`?Sa(
} S|AM9*k9
} "pxzntY|
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publicint getNextIndex(){ #eP
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int nextIndex = getStartIndex() + 2B~wHv
lkIn%=Z
pageSize; z~6y+
if(nextIndex >= totalCount) Upl6:xYrG
return getStartIndex(); T4e\0.If
else zkM"cb13q/
return nextIndex; !X>=l
} q*jNH\|
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publicint getPreviousIndex(){ Q3W#`6jpF
int previousIndex = getStartIndex() - d87vl13
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pageSize; vEM(bT=H
if(previousIndex < 0) Zx }&c |Q
return0; Z]w#vLR
else /h2b;"
return previousIndex; bte~c
} {'+QH)w(
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Ef
} Fh7'[>onw
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抽象业务类 ?C0l~:j7D
java代码: dGfVZDsr]
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/** UCrh/b Tm
* Created on 2005-7-12 3CjL\pIC
*/ FUK3)lT
package com.javaeye.common.business; WnFG{S{s
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import java.io.Serializable; k`HP"H
import java.util.List; bSwWszd~
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import org.hibernate.Criteria; u]^N&2UW
import org.hibernate.HibernateException; [mxTa\
import org.hibernate.Session; /76 1o\Q
import org.hibernate.criterion.DetachedCriteria; D-imL;|
import org.hibernate.criterion.Projections; m%+IPZ2m
import %m5Q"4O
{MAQ/5
org.springframework.orm.hibernate3.HibernateCallback; v}G]X Z8
import z7.|fE)<6
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org.springframework.orm.hibernate3.support.HibernateDaoS C9n}6Er=,
jt~Qu-
upport; 5pNY)>]t=
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import com.javaeye.common.util.PaginationSupport; g3@Rl2yQJ
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public abstract class AbstractManager extends ~wnOV#v
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HibernateDaoSupport { 0rk]/--FGJ
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privateboolean cacheQueries = false; M/D)".;
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privateString queryCacheRegion; kpwt]]e*
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publicvoid setCacheQueries(boolean Oh.ZPG=
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cacheQueries){ 1RLY $M
this.cacheQueries = cacheQueries; WlB'YL-`g
} ;P &y,:<m:
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publicvoid setQueryCacheRegion(String 5 v^yQ<70
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queryCacheRegion){ h)lPi
this.queryCacheRegion = b/$km?R
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queryCacheRegion; A|#`k{+1-
} IJOvnZ("A
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publicvoid save(finalObject entity){ U;_[b"SW%
getHibernateTemplate().save(entity); 4Ph0:^i_
} vP%tk s+.
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); Mj>}zbpk/
} js^ ,(CS
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publicvoid update(finalObject entity){ .Hhh i
getHibernateTemplate().update(entity); 1L7{p>;-dO
} C<^YVeG
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publicvoid delete(finalObject entity){ }F6<w{|
getHibernateTemplate().delete(entity); {>3\N0e5
} |s7`F%
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publicObject load(finalClass entity, pnyWcrBf
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finalSerializable id){ %U7.7dSOI;
return getHibernateTemplate().load -b&{+= ^c
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(entity, id); 4 PLk
} ,:Jus
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publicObject get(finalClass entity, $aCd/&
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finalSerializable id){ 3FSqd<t;D
return getHibernateTemplate().get g3n'aD@'x
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(entity, id); P`4]-5gE
} dhg~$CVO
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publicList findAll(finalClass entity){ BC>=B@H0
return getHibernateTemplate().find("from i=a-<A5x
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" + entity.getName()); |LG4=j.l
} gyHHoZc3
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publicList findByNamedQuery(finalString 8VG!TpX/B
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namedQuery){ &K_)#v`|
return getHibernateTemplate Tl]e%A`|
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().findByNamedQuery(namedQuery); vgt]:$
} m ~#!
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publicList findByNamedQuery(finalString query, UEs7''6RM
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finalObject parameter){ +i ?S
return getHibernateTemplate +=Jir1SLV
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().findByNamedQuery(query, parameter); W/z7"#
} x_=n-lAF
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publicList findByNamedQuery(finalString query, z't??6
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finalObject[] parameters){ .xzEAu ;
return getHibernateTemplate {u{@jp
@}_WE,r
().findByNamedQuery(query, parameters); |@?%Ct
} !?f5>Bl
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publicList find(finalString query){ C$Lu]pIL*
return getHibernateTemplate().find r0t^g9K0
pA.J@,>`}
(query); >4Y3]6N0.F
} rD?L
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publicList find(finalString query, finalObject cUqn<Z<n
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parameter){ *D4hq=
return getHibernateTemplate().find V6$xcAE"</
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(query, parameter); ^m#-9- `
} R_]{2~J+
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public PaginationSupport findPageByCriteria K/m3
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(final DetachedCriteria detachedCriteria){ ?7:KphFX)
return findPageByCriteria mS>xGtD&K
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Rtb :nJ8
} v}@xlB=
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public PaginationSupport findPageByCriteria #ywk|k5z]
M)*\a/6?{
(final DetachedCriteria detachedCriteria, finalint 6-`|:[Q~
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startIndex){ DU%w1+u
return findPageByCriteria 1}hIW":3Sr
4%WzIzRb
(detachedCriteria, PaginationSupport.PAGESIZE, ~/NKw:
ZZQG?("S'
startIndex); YDC mI@
} hLJM%on
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public PaginationSupport findPageByCriteria 4?N8R$
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(final DetachedCriteria detachedCriteria, finalint !-s!f&_
,1'4o3
pageSize, pZ`|iLNl-
finalint startIndex){ =_j vk.
return(PaginationSupport) h%WE=\,Qp
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getHibernateTemplate().execute(new HibernateCallback(){ xw{-9k-~
publicObject doInHibernate A5,t+8`aci
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(Session session)throws HibernateException { \txbhWN
Criteria criteria = jq'!UN{
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a
detachedCriteria.getExecutableCriteria(session); &DqE{bBd!
int totalCount = dd2[yKC`
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((Integer) criteria.setProjection(Projections.rowCount d0'JC*
"5cM54Z0
()).uniqueResult()).intValue(); k6`6Mjbc
criteria.setProjection L
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(null); G!4(BGx&
List items = zf3v5Hk
yH][(o=2
criteria.setFirstResult(startIndex).setMaxResults AM=z`0so
kq\)MQ"/X
(pageSize).list(); .CP&bJP%
PaginationSupport ps = s
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new PaginationSupport(items, totalCount, pageSize, :akT 'q#
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startIndex); l
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return ps; t|t#vcB
} kd"N29
}, true); a^ ,(v
} w[P4&?2:
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:
public List findAllByCriteria(final 0"~i^
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DetachedCriteria detachedCriteria){ ?` SUQm
return(List) getHibernateTemplate XMG]Wf^%\<
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().execute(new HibernateCallback(){ )M2F4[vcb
publicObject doInHibernate ;Eu3[[V
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(Session session)throws HibernateException { 5zON}"EC
Criteria criteria = "
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detachedCriteria.getExecutableCriteria(session); 1;<R#>&,*
return criteria.list(); x@8a''
} KZ~*Nz+H2
}, true); R$zH]
} 6q
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public int getCountByCriteria(final #c^^=Z
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DetachedCriteria detachedCriteria){ 9@+5LZR
Integer count = (Integer) 8,dBl!G=
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getHibernateTemplate().execute(new HibernateCallback(){ g+X}c/".
publicObject doInHibernate k4 F"'N
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(Session session)throws HibernateException { $1SUU F\.
Criteria criteria = TX
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detachedCriteria.getExecutableCriteria(session); e{Z &d
return EJ2yO@5O
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criteria.setProjection(Projections.rowCount hB{jUP)";
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()).uniqueResult(); Ar~"R4!
} HaIM#R32T
}, true); qWw\_S
return count.intValue(); $AHQmyg<
} EqI(|bFwy
} =-p$jXVW%
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用户在web层构造查询条件detachedCriteria,和可选的 qWb+r
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1^gl}^|B
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PaginationSupport的实例ps。 X.:]=,aGW
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ps.getItems()得到已分页好的结果集 X1~1&:V,<
ps.getIndexes()得到分页索引的数组 DK}"b}Fvq
ps.getTotalCount()得到总结果数 NO :a;
ps.getStartIndex()当前分页索引 rx}r~0i
ps.getNextIndex()下一页索引 GgKEP,O
ps.getPreviousIndex()上一页索引 )p*}e8L
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 m^qBxA
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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 p)+k=b
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一下代码重构了。 m)oJFF
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我把原本我的做法也提供出来供大家讨论吧: 4WK3.6GN
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首先,为了实现分页查询,我封装了一个Page类: $q 2D+_
java代码: G z)NwD
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/*Created on 2005-4-14*/ a0Zv p>Ft
package org.flyware.util.page; [+P#tIL
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/** x#:| }pR
* @author Joa Sf8{h|71
* `jOX6_z?I
*/ =z8f]/k*>
publicclass Page { i7ly[6{^pr
VH:]@x//{
/** imply if the page has previous page */ Od|$Y+@6
privateboolean hasPrePage; #^]n0!
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/** imply if the page has next page */ .aflsUD
privateboolean hasNextPage; yxc=Z0~1
V(E/'DR
/** the number of every page */ ccL~#c0P7
privateint everyPage; 3'X.}>o
(P`3 @H
/** the total page number */ [
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privateint totalPage; 4!wR_@W^El
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/** the number of current page */ e#k<d-sf6
privateint currentPage; x|vqNZ\F
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/** the begin index of the records by the current 2;?I>~
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query */ T'~!9Q
privateint beginIndex; Mec5h}^
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/** The default constructor */ C$5[X7'
public Page(){ %!1Q P[}K
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} @62Mk},9 c
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/** construct the page by everyPage KSrx[q
* @param everyPage ?y!E-&
* */ 95V@X
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public Page(int everyPage){ Zcc9e03
this.everyPage = everyPage; hh[jN7K
} x@Hc@R<!
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/** The whole constructor */ 2r ZxSg
public Page(boolean hasPrePage, boolean hasNextPage, ,tg0L$qC
{+@bZ}57
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int everyPage, int totalPage, 1u9LdkhnY
int currentPage, int beginIndex){ Ggb5K8D*
this.hasPrePage = hasPrePage; <=,6p>Eo[
this.hasNextPage = hasNextPage; -uy`!A
this.everyPage = everyPage; pf7it5
this.totalPage = totalPage; [#sz WNfU
this.currentPage = currentPage; L~KM=[cn
this.beginIndex = beginIndex; `F>O; >i''
} fX|Y;S-@+
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/** Tq4-wE+
* @return W='>:H
* Returns the beginIndex. U,.![TP
*/ pt}X>ph{
publicint getBeginIndex(){ wLH] <k
return beginIndex; nxl[d\ap+n
} VZl6t;cn
+) m_o"hl
/** Pp5^@A
* @param beginIndex lO_UPC\@fw
* The beginIndex to set. E)fglYWs2
*/ s91JBP|B7
publicvoid setBeginIndex(int beginIndex){ UMcgdJB
this.beginIndex = beginIndex; z.I9wQ]X[
} mOlI#5H
ze]h..,]K
/** yiA<,!;4P
* @return _:"<[ >9
* Returns the currentPage. ,xx R\}
*/ 9\DQ>V TQ
publicint getCurrentPage(){ q')R4=0
K
return currentPage; `kJ^zw+
} `{xNXH]@
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/** O7 $hYk
* @param currentPage ~7Tc$
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* The currentPage to set. 6efnxxY}sa
*/ X7g1:L1Ys
publicvoid setCurrentPage(int currentPage){ G"XVn~]
this.currentPage = currentPage; VH1d$
} =>! Y{:
y(
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/** X.e7A/ClEo
* @return 5>\/[I/!
* Returns the everyPage. [E
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*/ c*@E_}C#
publicint getEveryPage(){ g'm+/pU)w)
return everyPage; 1OF&
*
} E3iW-B8u8
:B:"NyPA
/** 6 M*O{f
* @param everyPage hHMN6i
* The everyPage to set. byfJy^8G
*/ iS<I0\D
publicvoid setEveryPage(int everyPage){
MEGv}
this.everyPage = everyPage; b^$|Nz;
} Sh8"F@P8
7fba-7-P
/** w2'f/
* @return pn5Q5xc
* Returns the hasNextPage. K]0JC/R6(@
*/ 5)MS~ii
publicboolean getHasNextPage(){ }dd8N5b
return hasNextPage; %GS(:]{n
} SK#(#OQoh
*9{Z$IA9w
/** u[
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* @param hasNextPage 6gs01c,BA
* The hasNextPage to set.
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*/ |YY_^C`"-
publicvoid setHasNextPage(boolean hasNextPage){ ]f({`&K5
this.hasNextPage = hasNextPage; ]&pds\
} M!XsJ<jN/
j_.5r&w
/** t8+X%-r
* @return ]@Uq=?%
* Returns the hasPrePage. |VNnOM
*/ nPy$D-L,
publicboolean getHasPrePage(){ G8Y<1%`<
return hasPrePage; % V8U(z
} #Ibp(
2P@sn!*{1
/** uvG]1m#
* @param hasPrePage dKxyA"@
* The hasPrePage to set. pxh"B\"4*
*/ bq:(u4 3
publicvoid setHasPrePage(boolean hasPrePage){ I\$X/t +dH
this.hasPrePage = hasPrePage; cbT7CG
} #a8B/-
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/** @-!}BUs?
* @return Returns the totalPage. suzZdkMA
* 65aK2MS@
*/ !74S
publicint getTotalPage(){ W|g4z7Pb
return totalPage; 7M<'/s
} F6{bjv2A
/Id%_,}Kb
/** J.xPv)1'
* @param totalPage *=I}Qh(1
* The totalPage to set. #/<&*Pu5t
*/ U5.LDv;
publicvoid setTotalPage(int totalPage){ /q`xCS
this.totalPage = totalPage; 0p}D(m2B
} 70Wgg ty
?1K#dC52#
} vbC\?\_
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< F.hZGss7
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 3GhRWB-U
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个PageUtil,负责对Page对象进行构造: NP/Gn6fr
java代码: f m)pulz
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/*Created on 2005-4-14*/ Yd=>K HVD
package org.flyware.util.page; sEGO2xeI
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import org.apache.commons.logging.Log; K)DDk9*
import org.apache.commons.logging.LogFactory; L"4mL,
^5h]Y;tx
/** ;E3>ay6m8
* @author Joa <?riU\-]y
* ='s(|
*/ [nrYpb4
publicclass PageUtil { G?;e-OhV
f-`)^5E
privatestaticfinal Log logger = LogFactory.getLog 6MT1$7|P&x
Z:sg}
(PageUtil.class); YH\OFg@7
:?g:~+hfO
/** $',K7%y
* Use the origin page to create a new page z4jR[x,
* @param page lrIS{MJ+-
* @param totalRecords &)AVzN+*h
* @return zGAq-<
*/ _0]S69lp
publicstatic Page createPage(Page page, int #/Vh|UeX
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totalRecords){ $JMXV
return createPage(page.getEveryPage(), CkoLTY
'+?"iVVo
page.getCurrentPage(), totalRecords); ZK@N5/H(
} B1>/5hV}
8TLgNQP
/** z6jc8Z=O
* the basic page utils not including exception (nlvl?\d
hog=ut
handler gT0BkwIV
* @param everyPage CsoiyY -2
* @param currentPage e%@~MQ-
* @param totalRecords >aj7||K
* @return page > dI LF
*/ UQC=g
publicstatic Page createPage(int everyPage, int Vr^n1sgE}r
4{rZppm
currentPage, int totalRecords){ +'I+o5*
everyPage = getEveryPage(everyPage); 3L_\`Ia9
currentPage = getCurrentPage(currentPage); GzI yP(U
int beginIndex = getBeginIndex(everyPage, {MCi<7j<?
#xQr<p$L6
currentPage); +zaA,e?\
int totalPage = getTotalPage(everyPage, 5qZ1FE
b\$}>O
totalRecords); a1+#3X.
boolean hasNextPage = hasNextPage(currentPage, X[PZg{
2[RoxKm
totalPage); %.^_Ps0
boolean hasPrePage = hasPrePage(currentPage); T_@K&<
@` 1Ds
returnnew Page(hasPrePage, hasNextPage, *E/`KUG]
everyPage, totalPage, {=!b/l;@
currentPage, QLEKsX7p>
t>urc
beginIndex); :U3kW8;UMP
} qln3 k`
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privatestaticint getEveryPage(int everyPage){ %_RQx2
return everyPage == 0 ? 10 : everyPage; D#il*
} /H(?
2IHC
a!<8\vzg
privatestaticint getCurrentPage(int currentPage){ si`A:14R
return currentPage == 0 ? 1 : currentPage; 52 fA/sx
} Crho=RJPR
ZniB]k1
privatestaticint getBeginIndex(int everyPage, int
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q
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currentPage){ zF8dKFE~
return(currentPage - 1) * everyPage; )z73-M V"
} q Gw -tPD<
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privatestaticint getTotalPage(int everyPage, int njScz"L~
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totalRecords){ s:/8[(A
int totalPage = 0; 0=* 8
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if(totalRecords % everyPage == 0) [E!oQVY
totalPage = totalRecords / everyPage; K9$>Yxe|
else \?0&0;5
totalPage = totalRecords / everyPage + 1 ; Tx|Ir+f6L
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return totalPage; e;Ti&o}
} 6y+Kjd/D
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privatestaticboolean hasPrePage(int currentPage){ [ sN EHf
return currentPage == 1 ? false : true; (@<lRA
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} 6r"eN%m
wkA+j9.
privatestaticboolean hasNextPage(int currentPage, !}v=N";c
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int totalPage){ Ljxz.2LGr
return currentPage == totalPage || totalPage == -Zf@VW,NI
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0 ? false : true; Hv
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} &]e'KdXF
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} ,SynnE68
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Q&wB$*u
v(B<Nb
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 ^W'fA{sr
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做法如下: z=rT%lz6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 8jd;JPz@\
P
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的信息,和一个结果集List: %QH)' GJQ
java代码: |Y$uqRdV
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/*Created on 2005-6-13*/ 3nT^?;-
package com.adt.bo; r@v,T8
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import java.util.List; \>jLRb|7Ts
5R'TcWf#W
import org.flyware.util.page.Page; ohF JZ'
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/** =yr0bGy`-
* @author Joa y4*U6+ #.
*/ A'q#I>j`
publicclass Result { TD1 [
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private Page page; C~nzH,5
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private List content; Bt>}rYz1
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/** S4^vpY
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* The default constructor mL{B!Q
*/ 5mJ JU
public Result(){ $FlW1E j
super(); 'oF%,4 !Y
} 'MEz|Z
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/** OTGofd2zf
* The constructor using fields <KE 1f7c
* )~+E[|
* @param page +=q$ x Ia
* @param content Xf02"PXC
*/ : >6F+XZ
public Result(Page page, List content){ MHh~vy'HB5
this.page = page; Wc,~ {
this.content = content; w.H%R-Be
} OUeyklw
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/** )-0kb~;|
* @return Returns the content. tSVc|j
*/ ?&|5=>u2}$
publicList getContent(){ \R|4( +]x
return content; HG+%HUO$
} ]bj&bk#
.q
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/** Xe<sJ.&Wf
* @return Returns the page. ]$Yvj!K*Q
*/ Fs{x(_LOr
public Page getPage(){ q;<h[b?
return page; ~i~7na|
} E=e*VEjy
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/** Sz^
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* @param content @\|_
* The content to set. R_sr?V|"
*/ `8^TTQ
public void setContent(List content){ CjlKMbnBH
this.content = content; h3bff#<K
} .2%zC & ;
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/** Y( 3Bp\6
* @param page 99:C"`E{
* The page to set. n` xR5!de
*/ &d"G/6
publicvoid setPage(Page page){ .WPV dwV4U
this.page = page; =R #Qx,
} M[6:p2u
} {$R' WXVs
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2. 编写业务逻辑接口,并实现它(UserManager, :?/cPg'D
7(qE0R&@
UserManagerImpl) P"W2(d
java代码: &Q>k7L!
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a4XU?-sUh
/*Created on 2005-7-15*/ @xbQ Ye%J
package com.adt.service; A9wh(P0\
!q9+9 *6
import net.sf.hibernate.HibernateException; 2
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import org.flyware.util.page.Page; zx-81fx+k
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import com.adt.bo.Result; c- }X_)U }
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/** 95YL]3V
* @author Joa %]>KvoA
*/ pgOQIzu
publicinterface UserManager { KO]T<R
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public Result listUser(Page page)throws }HY-uQ%@g
c
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HibernateException; !{^PO<9
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} jg.QRny^
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Qk,I^1w?7
ch0{+g&
t0IEaj75c
java代码: <-[wd.M_
pov)Z):}G<
D|Q#gcWp o
/*Created on 2005-7-15*/ m06ALD_
package com.adt.service.impl; 3wC' r
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import java.util.List; }[4r4 1[
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import net.sf.hibernate.HibernateException; 6"~P/\jP
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import org.flyware.util.page.Page; @ Wd9I;hWv
import org.flyware.util.page.PageUtil; ~},=OF-b
k~jP'aD
import com.adt.bo.Result; h"_MA_]~
import com.adt.dao.UserDAO; dHv68*^\'
import com.adt.exception.ObjectNotFoundException; =~=*&I4Dp
import com.adt.service.UserManager; >[_f3;P
d4?Mi2/jF
/** 22.8PO0
* @author Joa n
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*/ paKSr|O
publicclass UserManagerImpl implements UserManager { k}
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private UserDAO userDAO; )pq;*~IBI
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/** SV2M+5#;
* @param userDAO The userDAO to set. Of4^?`
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*/ "x 3lQ
publicvoid setUserDAO(UserDAO userDAO){ Q$="_y2cTA
this.userDAO = userDAO; hM{{\yZS
} Uc@Ao:
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/* (non-Javadoc) Jo@|"cE=
* @see com.adt.service.UserManager#listUser no<
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(org.flyware.util.page.Page) Z@]e{zO
*/ oxz OA
public Result listUser(Page page)throws xHz[t6;4;
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HibernateException, ObjectNotFoundException { z@B=:tf
int totalRecords = userDAO.getUserCount(); Fsif6k=4
if(totalRecords == 0) rvXWcu -"
throw new ObjectNotFoundException K95p>E`9e
">y%iE
("userNotExist"); [Pq}p0cD
page = PageUtil.createPage(page, totalRecords); |MFF7z{%
List users = userDAO.getUserByPage(page); a2
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returnnew Result(page, users); o]; [R
} L$IQuy
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} %*`J k#W:
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 a hR ^
A-T]9f9
询,接下来编写UserDAO的代码: 2JJ"O|Ibz
3. UserDAO 和 UserDAOImpl: L1Iz<>
java代码: }>VG~u8
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v"OY 1<8
/*Created on 2005-7-15*/ 9hOJvQ2U]
package com.adt.dao; %we u 1f
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import java.util.List; V>A.iim
n~A%q,DmF
import org.flyware.util.page.Page; x)rM/Kq
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import net.sf.hibernate.HibernateException; <xgTS[k
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/** ~~SwCXZ+b^
* @author Joa >i5acuth
*/ ;S57w1PbVA
publicinterface UserDAO extends BaseDAO { &:, dJ
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publicList getUserByName(String name)throws 1DvR[Lx%
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HibernateException; fp[|M
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publicint getUserCount()throws HibernateException; 1#0{@35
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publicList getUserByPage(Page page)throws q^r#F#*1l
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HibernateException; oE(7v7iY
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} mw='dFt
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java代码: GQ9\'z#+
1$%V{4bJ
^sVX)%
/*Created on 2005-7-15*/ 76Vl6cPu>
package com.adt.dao.impl; Er+nk`UR_
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import java.util.List; ?ON-+u
!-,t'GF(
import org.flyware.util.page.Page; Z| V`B `
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import net.sf.hibernate.HibernateException; WC|.g,9#
import net.sf.hibernate.Query; gMaN)ESqd4
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import com.adt.dao.UserDAO; p~9vP)74u
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/** S6AU[ASY.
* @author Joa `~ * @q!
*/ JXu$ew>q
public class UserDAOImpl extends BaseDAOHibernateImpl w\DVzeW(
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implements UserDAO { &&VqD
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/* (non-Javadoc) 3Ei5pX =g
* @see com.adt.dao.UserDAO#getUserByName 86\S?=J-b
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(java.lang.String) I;Bjfv5
*/ UGuxV+Nwf
publicList getUserByName(String name)throws x
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JM\m)RH0
HibernateException { r%.do;5
String querySentence = "FROM user in class ])Qs {hs~s
|"9 #bU
com.adt.po.User WHERE user.name=:name"; i}o[- S4
Query query = getSession().createQuery ]@0NO;bK>F
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(querySentence); ]- 4QNc=
query.setParameter("name", name);
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return query.list(); a(v>Q*zNP
} !}r%
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/* (non-Javadoc) ?HV`|
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* @see com.adt.dao.UserDAO#getUserCount() X_g 3rv1J
*/ I=.z+#Y
publicint getUserCount()throws HibernateException { 8G5m{XTS(
int count = 0; hDp6YV,q
String querySentence = "SELECT count(*) FROM N~NQ6:R[
=@8H"&y`
user in class com.adt.po.User"; hQDTS>U
Query query = getSession().createQuery r?*NhLG;
(>I`{9x>6
(querySentence); l+g9 5mjP
count = ((Integer)query.iterate().next pTyi!:g3W
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()).intValue(); 3neIR@W
return count; d GFGr}&s
} KhW;RD
}GZ}Q5
/* (non-Javadoc) `p7&>
BOA
* @see com.adt.dao.UserDAO#getUserByPage K%Rj8J7|u?
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(org.flyware.util.page.Page) GKFq+]W
*/ 3RR_fmMT)
publicList getUserByPage(Page page)throws 1[t=XDz/e
U=o"32n+
HibernateException { zKsz*xv6b
String querySentence = "FROM user in class v!FMs<
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com.adt.po.User"; Gsc\/4Wx
Query query = getSession().createQuery 0sh/|`\
zWb4([P;
(querySentence); Xj5~%DZp
query.setFirstResult(page.getBeginIndex()) XFh>U7z.
.setMaxResults(page.getEveryPage()); DmBS0NyR7Y
return query.list(); Z KOXI%~Mc
} _"#!e{N|
n]u<!.X
} yH<$k^0r*
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至此,一个完整的分页程序完成。前台的只需要调用 _C+b]r/E
`r_m+]
userManager.listUser(page)即可得到一个Page对象和结果集对象 k~|-gfFP
D Kw*~0
的综合体,而传入的参数page对象则可以由前台传入,如果用 j$7Xs"
h#hxOVl%x
webwork,甚至可以直接在配置文件中指定。 5 XA=G
I6s3+x;O
下面给出一个webwork调用示例: 5&e<#"
java代码: mnID3=JF
Y2[A2Uy$ef
?*oKX
/*Created on 2005-6-17*/ J-<^P5
package com.adt.action.user; BkZV!Eg
C( id=F
import java.util.List; $\"9<o|h
-dO'~all
import org.apache.commons.logging.Log; ]D!k&