Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %{!*)V\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3V?JX5X\
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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 iOkRB[hi
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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 3lcd:=
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。 Obgn?TAVX
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分页支持类: NTASrh
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java代码: sWX iY
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package com.javaeye.common.util; \L>3E#R-Q
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import java.util.List; a6wPkf7-H
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publicclass PaginationSupport { dYrw&gn
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publicfinalstaticint PAGESIZE = 30; 0-M.>fwZ=
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privateint pageSize = PAGESIZE; nsIx5UA_n
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privateList items; 3jZPv;9OC
es 8%JTi
privateint totalCount; &<2~7?$!
m X{_B!j^
privateint[] indexes = newint[0]; @W[`^jfQ
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privateint startIndex = 0; |=fa`8mG
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public PaginationSupport(List items, int rJH u~/_Dq
V*5 ~A[r
totalCount){ 3B8\r}L
setPageSize(PAGESIZE); XZde}zUWn
setTotalCount(totalCount); Yj)H!Cp.xD
setItems(items); 0}}b\!]9
setStartIndex(0); xTiC[<j
} f40 xS7-Q0
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public PaginationSupport(List items, int 1vk&;
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totalCount, int startIndex){ i%w[v_j
setPageSize(PAGESIZE); |(G^3+5Uwm
setTotalCount(totalCount); LlOUK2tZ
setItems(items); 8MqKS}\H
setStartIndex(startIndex); J:LwO
} d|#sgGM<8
6yH(u}!.
public PaginationSupport(List items, int *;@V5[^3I?
Ox9WH4E
totalCount, int pageSize, int startIndex){ x8
:
setPageSize(pageSize); bwN>E+
setTotalCount(totalCount); 7vO3+lT/Y;
setItems(items); xc{$=>'G
setStartIndex(startIndex); m%au* 0p
} "=8= G
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publicList getItems(){ {WJ9!pA!lk
return items; }8tD|t[
} ;U$Fz~rJ
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publicvoid setItems(List items){
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this.items = items; R@zl?>+
} xNDX(_U>\
f/+UD-@%m
publicint getPageSize(){ OwRH
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return pageSize; 7HfA{.|m
} ip.aM#
${ fJ]
publicvoid setPageSize(int pageSize){ o&WKk5$
this.pageSize = pageSize; s.y wp{EF
} [HO=ii]Wb
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publicint getTotalCount(){ f4{O~?=
return totalCount; <E/"v
} wP:ab
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publicvoid setTotalCount(int totalCount){ 'KL!)}B$h
if(totalCount > 0){ vu7F>{D
this.totalCount = totalCount; .$&_fUY
int count = totalCount / )/uu~9SFd
v:.`~h/b
pageSize; MYI*0o;
if(totalCount % pageSize > 0) j!m42
count++; >Vp#
indexes = newint[count]; ~t0\Q; @($
for(int i = 0; i < count; i++){ * F[;D7sZ~
indexes = pageSize * 3pQ^vbQ"
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i; 9qe< bds1
} JSKAlw
}else{ +E5EOo{ `|
this.totalCount = 0; W[ZW=c
} 2g'o5B\*
} Mzfuthq=@
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publicint[] getIndexes(){ x,LQA0
return indexes; 0=g~ozEW&
} 67,@*cK3?J
`]*BDSvE
publicvoid setIndexes(int[] indexes){ 7l+>WB_]
this.indexes = indexes; %N.qu_,IZ
} w+MCOAB
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publicint getStartIndex(){ (zv)cw%
return startIndex; (>.+tq}
} ~m0l_:SF
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publicvoid setStartIndex(int startIndex){ b Ag>;e(
if(totalCount <= 0) j=>:{`*c
this.startIndex = 0; /U1"P
elseif(startIndex >= totalCount) w]-,X`
this.startIndex = indexes Gh.@l\|tf
7|vB\[s
[indexes.length - 1]; ;`CNe$y
elseif(startIndex < 0) T1Gy_ G/
this.startIndex = 0; ;Nfd
else{ fG{ 9doUD
this.startIndex = indexes e/S^Rx4W
+#$(>6Zu"{
[startIndex / pageSize]; !/]vt?v#^
} (j*1sk
} .PAR
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publicint getNextIndex(){ =A yDVWpE
int nextIndex = getStartIndex() + 335\0~;3
aM2[<m}
pageSize; *Y!c6eA
if(nextIndex >= totalCount) 9bE/7v
return getStartIndex(); }iu(-{Z
else 97XGJ1HI
return nextIndex; Td|x~mZv:
} P. V #
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publicint getPreviousIndex(){ /d/Quro
int previousIndex = getStartIndex() - #"3az8u
k~P{Rm;F
pageSize; +0)zB;~7
if(previousIndex < 0) c<T'_93
return0; `% a+LU2
else utJz e
return previousIndex; gJn_Z7Mg J
} $IdY(f:.:5
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} >mWu+Nn:
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抽象业务类 slV7,4S&!
java代码: y%9Q]7&=
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/** +ISXyGu
* Created on 2005-7-12 C/sDyv$
*/ ^KK9T5H
package com.javaeye.common.business; 8N58w)%7`
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import java.io.Serializable; g;M\4o
import java.util.List; *`(/wE2v]
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import org.hibernate.Criteria; JW`Kh*,~<
import org.hibernate.HibernateException; 4
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import org.hibernate.Session; ]0g%)f uMf
import org.hibernate.criterion.DetachedCriteria; |H(Mmqgk
import org.hibernate.criterion.Projections; [;]@PKW?w
import JN{xh0*
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org.springframework.orm.hibernate3.HibernateCallback; tFYIKiq2
import N]p|c3D
<;?&<qMo,P
org.springframework.orm.hibernate3.support.HibernateDaoS aD5G0d?u
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upport; Ya_4[vR<
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import com.javaeye.common.util.PaginationSupport; c/c%-=
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public abstract class AbstractManager extends CCX!>k]
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HibernateDaoSupport { i"rrM1/r
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privateboolean cacheQueries = false; $B
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privateString queryCacheRegion; >VAZ^kgi
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publicvoid setCacheQueries(boolean Z~Mq5#3F
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cacheQueries){ LqHeLN
this.cacheQueries = cacheQueries; aoZ`C3
} ?Z<2zm%qV
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publicvoid setQueryCacheRegion(String kRk=8^."By
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queryCacheRegion){ t?-7Z6
this.queryCacheRegion = FC= %_y
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queryCacheRegion; }/Wd9x
} g>[|/ z P
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publicvoid save(finalObject entity){ UeRx ^
getHibernateTemplate().save(entity); Xcq9*!%o
} -9S.G
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publicvoid persist(finalObject entity){ #0-!P+c[
getHibernateTemplate().save(entity); JuGQS24
} *5i~N}
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publicvoid update(finalObject entity){ t;DZ^Z"{
getHibernateTemplate().update(entity); ZOFBT(oV
} r: _-Cj
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publicvoid delete(finalObject entity){ ZS uMQ32
getHibernateTemplate().delete(entity); ;z9(
} NVnKgGlHgd
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publicObject load(finalClass entity, "9[K
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finalSerializable id){ y*M,&,$
return getHibernateTemplate().load Q<L.!%vu}
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(entity, id); {-rK:*yP'u
}
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publicObject get(finalClass entity, K/~+bq#+
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finalSerializable id){ yaf&SR@7k{
return getHibernateTemplate().get ^i{B8]2,
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(entity, id); cU25]V^{\
} r\Wp\LfY&{
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publicList findAll(finalClass entity){ XM/P2=;
return getHibernateTemplate().find("from +a&-'`7g
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" + entity.getName()); g<s[6yA
} *@Z/L26s;=
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publicList findByNamedQuery(finalString Rg&6J#h
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namedQuery){ ^zGgvFf>
return getHibernateTemplate " 7!K'i
|}*k|
().findByNamedQuery(namedQuery); jlER_I]
} Jkt
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publicList findByNamedQuery(finalString query, DYH-5yX7
(
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finalObject parameter){ A.vcE
return getHibernateTemplate {KL<Hx2M
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().findByNamedQuery(query, parameter); J+&AtGq]u
} 1){1 HK
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publicList findByNamedQuery(finalString query, tc@U_>{
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finalObject[] parameters){ gFJ&t^yL
return getHibernateTemplate -e%=Mpq.
hQBeM7$F_
().findByNamedQuery(query, parameters); 0$,Ag;"^?
} Be2@9
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publicList find(finalString query){ uw+v]y
return getHibernateTemplate().find 8Es]WR5
^
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(query); `h S<F"
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} 8N(bLGUG
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publicList find(finalString query, finalObject ~0fT*lp
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parameter){ 3WJ> T1we
return getHibernateTemplate().find v?<x"XKR
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(query, parameter); q yy.3-(
} P58U8MEG
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public PaginationSupport findPageByCriteria 6!bA~"N
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(final DetachedCriteria detachedCriteria){ Xr M[8a
return findPageByCriteria v%&f00
C3 0b}2
(detachedCriteria, PaginationSupport.PAGESIZE, 0); !j4C:L3F
} "JVzv U]
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public PaginationSupport findPageByCriteria Sct-,K%i
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(final DetachedCriteria detachedCriteria, finalint N>Y`>5
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startIndex){ f\~e&`PV
return findPageByCriteria D{.%Dr?
@D"#B@j
(detachedCriteria, PaginationSupport.PAGESIZE, HcHfwLin0
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startIndex); 2>fG}qYy$
} yL.si)h(p
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public PaginationSupport findPageByCriteria lIzJO$8cM
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(final DetachedCriteria detachedCriteria, finalint A
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pageSize, #Opfc8pm'
finalint startIndex){ '[Oi_gE.
return(PaginationSupport) AXPUJ?V
u{H,i(mx?
getHibernateTemplate().execute(new HibernateCallback(){ 7L;yN..0
publicObject doInHibernate e^&YQl
um#;S;
(Session session)throws HibernateException { (fh:q2E#
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); $'9r=#EH
int totalCount = Z
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((Integer) criteria.setProjection(Projections.rowCount f`A
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()).uniqueResult()).intValue(); lu(G3T8
criteria.setProjection (P`{0^O"}
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(null); O|y-nAZgU
List items = -&,NM
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criteria.setFirstResult(startIndex).setMaxResults fwsq:
h%=b"x
(pageSize).list(); xA!o"VZPq7
PaginationSupport ps = $Q{1^
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new PaginationSupport(items, totalCount, pageSize, K:y q^T7
zo} SS[
startIndex); Vg
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return ps; i6`8yw
} _&(ij(H
}, true); JEHV\=
} mnmwO(.
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public List findAllByCriteria(final sgX}`JH?z
w,}}mC)\*
DetachedCriteria detachedCriteria){ p+8]H
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return(List) getHibernateTemplate 7vj[ AOq3l
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().execute(new HibernateCallback(){ &g& &-=7)
publicObject doInHibernate o=`9JKB~
(
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(Session session)throws HibernateException { }(o/+H4
Criteria criteria = LG<lZ9+y
_L$)~},cT
detachedCriteria.getExecutableCriteria(session); =r-Wy.a@
return criteria.list(); Cg{$$&_(Hj
} qsk71L
}, true); ^w&TTo(
} lZ)u4_
}7.q[ ^oF
public int getCountByCriteria(final EL}v>sC
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DetachedCriteria detachedCriteria){ *|E@81s#
Integer count = (Integer) C>K/C!5?
s}z,{Y$-t
getHibernateTemplate().execute(new HibernateCallback(){ t9`NCng
5
publicObject doInHibernate ~ml\|
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(Session session)throws HibernateException { \pzvoj7{
Criteria criteria = vq5I 2
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detachedCriteria.getExecutableCriteria(session); O4E2)N
return |@ldXuYb
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criteria.setProjection(Projections.rowCount hYWWvJ)S
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()).uniqueResult(); X^.r@tT
} +;!w;t
}, true); S~TJF}[k^6
return count.intValue(); P)\f\yb
} 3\WES!
} F
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用户在web层构造查询条件detachedCriteria,和可选的 V3+%KkN
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |1<Z3\+_/
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PaginationSupport的实例ps。 *ap#*}r!Nk
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ps.getItems()得到已分页好的结果集 lLDHx3+
ps.getIndexes()得到分页索引的数组 iIF'!K=q
ps.getTotalCount()得到总结果数 .XE]vo
ps.getStartIndex()当前分页索引 ?#[K&$}
ps.getNextIndex()下一页索引 l2v}PALs
ps.getPreviousIndex()上一页索引 K5ph x
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <5#e.w
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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 }dR*bG
UetmO`qju
一下代码重构了。 zSH#j RDV
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我把原本我的做法也提供出来供大家讨论吧: Lf:Z
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b7,qzh
首先,为了实现分页查询,我封装了一个Page类: 0IdD
java代码: avz 4&
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/*Created on 2005-4-14*/ `^}9= Q'r
package org.flyware.util.page; tp]|/cx4
=@z"k'Vl`
/** eo8 0L
* @author Joa (BGipX4
* w}i.$Qt
*/ >6dgf`U
publicclass Page { Sce9R?II
Zk[#BUA
/** imply if the page has previous page */ 5jLDe~
privateboolean hasPrePage; t(yv
#n7{ 3)
/** imply if the page has next page */ \[&]kPcDl
privateboolean hasNextPage; ')aYkO{%sb
?`XKaD!
f
/** the number of every page */ DXGO-]!!0
privateint everyPage; y*D 8XI$
s^
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/** the total page number */ 5eLPn
privateint totalPage; DNy)\+[
# 9t/j`{
/** the number of current page */ @e7+d@O<
privateint currentPage; 3IkG*enI
vKt_z@{{L
/** the begin index of the records by the current ;4bu=<%
8dH|s#.4um
query */ N#:"X;
privateint beginIndex; h CiblM
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u&Fm}/x
/** The default constructor */ 6uyf
public Page(){ 3{l"E(qqZ
0{yx*}.
} Ame%:K!t
^:j$p,0e*S
/** construct the page by everyPage D4|_?O3|m
* @param everyPage WKf~K4BL>
* */ -UVWs2W'$
public Page(int everyPage){ rUO{-R
this.everyPage = everyPage; 8f.La
} On^#x]
8{YxUD
/** The whole constructor */ V("1\
public Page(boolean hasPrePage, boolean hasNextPage, {V8Pn2mlo
#L)rz u
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int everyPage, int totalPage, 'w2;oO
int currentPage, int beginIndex){ Z:_y,( 1Q
this.hasPrePage = hasPrePage; "ir*;|
this.hasNextPage = hasNextPage; "->:6Oe2
this.everyPage = everyPage; B(falmXJ
this.totalPage = totalPage; ||V:',#,W
this.currentPage = currentPage; -eMRxa>
this.beginIndex = beginIndex; qAS^5|(b[
} :m\KQ1sq
u_BSWhiW
/** hqPn~Tq
* @return q*OKA5
* Returns the beginIndex. YYHm0pc
*/ z@i4dC
publicint getBeginIndex(){ Q\76jD`m\
return beginIndex; iIFQRnpu;3
} <B`V
4lA+V,#
/** K^Ht$04
* @param beginIndex z"3c+?2
* The beginIndex to set. (zBQ^97]
*/ Z3dd9m#.]
publicvoid setBeginIndex(int beginIndex){ B/OO$=>(
this.beginIndex = beginIndex; V1.F`3h~
} )a\h5nQI)
+b+sQ<w?.
/** D;]%
* @return 7&4,',0VL
* Returns the currentPage. L|LTsRIq
*/ arZIe+KW
publicint getCurrentPage(){ <Xx\F56zp
return currentPage; I8?[@kg5b'
} @nu/0+8h{
TXcKuo=
/** l'QR2r7&.
* @param currentPage TeJ
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* The currentPage to set. iC]lO
*/ w>uZ$/
publicvoid setCurrentPage(int currentPage){ >{a,]q*
this.currentPage = currentPage; p( *3U[1
} n^N]iw{G
M-N2>i#
/** +`8)U 3u0
* @return >nQyF
* Returns the everyPage. 5>)jNtZ
*/ / JB4 #i7
publicint getEveryPage(){ )*h~dx_c m
return everyPage; 9#ft;c
} $x;h[,y
$sZHApJV+
/** *a!!(cZZ
* @param everyPage dn_OfK
* The everyPage to set. 8n5nHne
*/ aUK4{F ;
publicvoid setEveryPage(int everyPage){ tY=%@v'6?
this.everyPage = everyPage;
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} ,rQ)TT
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/** 2p>SB/
* @return Y)}%SP>,
* Returns the hasNextPage. +o]BjgG
*/ Aw;vg/#~md
publicboolean getHasNextPage(){ 'V#ew\
return hasNextPage; N?0y<S ?!
} C+XZDY(=Z
4rG 7\
/** 1m;*fs
* @param hasNextPage ,hLSRj{
* The hasNextPage to set. V(LFH9.Mp
*/ .A)Un/k7
publicvoid setHasNextPage(boolean hasNextPage){ v&2@<I>
this.hasNextPage = hasNextPage; SzX~;pFM0
} R Sz[6
t<F]%8S
/** #J724`
* @return ^G&D4uZ
* Returns the hasPrePage. ?K {1S
*/ JZ/O0PW
publicboolean getHasPrePage(){ ii
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return hasPrePage; BWdc^
} GA.bRN2CI2
AUsQj\Nm%
/** Fx5d@WNa>
* @param hasPrePage 6L9[U^`@
* The hasPrePage to set. d`uO7jlm
*/ v9m;vWp
publicvoid setHasPrePage(boolean hasPrePage){ +\GZ(!~
this.hasPrePage = hasPrePage; lk1Gs{(qhH
} @B[Cc`IN"
l/zC##1+.
/** P<!$A
* @return Returns the totalPage. (%y c5+f!
* 8`2<g0V2
*/ ,G|aLBn
publicint getTotalPage(){ 5;8B!%b
return totalPage; \K~fRUo]=c
} ;c
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#0hNk%X=
/** "%''k~UD4
* @param totalPage &4&33D
* The totalPage to set. .#55u+d,
*/ 4z%#ZIy3
publicvoid setTotalPage(int totalPage){ rn:zKTyhw
this.totalPage = totalPage; !L.
K)9I
} dP7Vsa+
s^YTI\L
\
} q%k(M[
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RE
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%=9yzIjbAt
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 5%?b5(mnD
RefRoCD1
个PageUtil,负责对Page对象进行构造: GyAgPz
java代码: U5CPkH1
Ldhk^/+
1Uemsx%'k
/*Created on 2005-4-14*/ q7f;ZK=f
package org.flyware.util.page; +O$:
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import org.apache.commons.logging.Log; 'K`Rbhy
import org.apache.commons.logging.LogFactory; ~,*YmB=Z
T<+ht8&M8
/** I+"?,Ej$K
* @author Joa
$.Q>M]xH
* R G0S
*/ Afy .3T @)
publicclass PageUtil { n5+S"
-}X?2Q
privatestaticfinal Log logger = LogFactory.getLog @>fO;*
a=*ALd_&0
(PageUtil.class); MuoctW
;=-j;x
/** 6L,lq;
* Use the origin page to create a new page R'I_xjC
* @param page hkwa ""-
* @param totalRecords WVWS7N\
* @return n(1wdl Ep
*/ 3p3WDL7
publicstatic Page createPage(Page page, int {[,Wn:
zn
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totalRecords){ >bA$SN
return createPage(page.getEveryPage(), UiR,^/8ED
r%F(?gKXkd
page.getCurrentPage(), totalRecords); _+\:OB[Y
} ,9Z2cgXwJ
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/** O}MZ-/z=o~
* the basic page utils not including exception xY2}Wr
j,
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handler %l:|2s:
* @param everyPage
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* @param currentPage xaWGa1V'z
* @param totalRecords Wm)-zvNY;
* @return page NFY|^*bll
*/ cZe'!CQS
publicstatic Page createPage(int everyPage, int tS (i711
6h2x~@
currentPage, int totalRecords){ t{Hh&HX
everyPage = getEveryPage(everyPage); 9^PRX
currentPage = getCurrentPage(currentPage);
!@pV)RUv7
int beginIndex = getBeginIndex(everyPage, 4`8IFK
to&N22a$
currentPage); AhvvuN$n%
int totalPage = getTotalPage(everyPage, lk_s!<ni
X'FEOF
totalRecords); 6Z(*cf/s
boolean hasNextPage = hasNextPage(currentPage, `10X5V@hP
E kBae=
totalPage); ]-um\A4f
boolean hasPrePage = hasPrePage(currentPage); /&]-I$G@
?dsf@\
returnnew Page(hasPrePage, hasNextPage, =[P%_v``
everyPage, totalPage, @PQrmn6w
currentPage, 5S%C~iB
D3S+LV
beginIndex); -9OMn}w/*
} ImWXzg3@{
EO#gUv
privatestaticint getEveryPage(int everyPage){ Fn86E dFM
return everyPage == 0 ? 10 : everyPage; b/sOfQ
} Ecxj9h,S
{sC@N![
privatestaticint getCurrentPage(int currentPage){ T-9k<,>?
return currentPage == 0 ? 1 : currentPage; |N:MZ#};
} YH[XRUa
{*QvC
g?
privatestaticint getBeginIndex(int everyPage, int T?X^0UdJj
cQT1Xi
currentPage){ >`7OcjLg
return(currentPage - 1) * everyPage; `'p`PyMt`
} k> b&xM!
rDVgk6
privatestaticint getTotalPage(int everyPage, int }RcK_w@Jx)
Hp\Ddx >Jd
totalRecords){ \!^i;1h0c3
int totalPage = 0; m[Z6VHn
uR#'lb`3
if(totalRecords % everyPage == 0) IQ3n@
totalPage = totalRecords / everyPage; .OmQ'
else ?k{|Lk
totalPage = totalRecords / everyPage + 1 ; L5Urg*GNL
@Q;i.u{V
return totalPage; Gn]d;5P=
} QXdaMc+Ck
aS,a_b]
privatestaticboolean hasPrePage(int currentPage){ CI,lkO|C
return currentPage == 1 ? false : true; K`hz
t
} u_N\iCYp
:T_'n,
privatestaticboolean hasNextPage(int currentPage, |d
$1wr
=G(*gx
int totalPage){ `#ul,%
return currentPage == totalPage || totalPage == F9MR5O"
Yeqvv
0 ? false : true; xC-BqVJ%_T
} CN7k?JO<
NMXnrvS&
kg<P t >
} 6m9 7_NRO
#2 \8?UPd
/xcJo g~F,
QhsMd-v
tXt:HVN
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 s=MT,
-b
cG[W3
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \a"i7Caa
oEJaH
做法如下: ]nUR;8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 cTM$ZNin
vYDSu.C@a
的信息,和一个结果集List: &vCeLh:s
java代码: ]/Vh{d|I&
);nz4/V
kI%peb?
/*Created on 2005-6-13*/ aD2*.ln><
package com.adt.bo; 8O6_iGTBh
4otl_l(`yv
import java.util.List; aqF+zPKs6
wa!zv^;N*
import org.flyware.util.page.Page; P+h6!=nD7
^|#>zCt^
/** :cy>c2
* @author Joa Q!yb16J
*/ +'|{1gB
publicclass Result { ,yICNtP
/}Yqf`CZy
private Page page; Hle\ON
6
}! Z"
private List content; pTWg
m\h
, 9mgYp2
/** 8lwFAiC8
* The default constructor h3kaD
*/ CM9 XPr
public Result(){
9RQU?
super(); Gzw@w{JBL
} A:eFd]E{(
PL@~Ys0
/** FEF"\O|Q
* The constructor using fields L}$z/jo
* +{.780|
* @param page }X]\VSF{
* @param content Kq&qE>Ju
*/ 2Z)4(,
public Result(Page page, List content){ ,h^r:g
this.page = page; %:3'4;jh%
this.content = content; ?6f7ld5
} 9@ndi u[
|jT2W
/** %x2uP9
* @return Returns the content. n!G.At'JP
*/
aG(hs J)
publicList getContent(){ w9f
_b3
return content; hGI+:Js6
} Q".g.k
7X}TB\N1
/** sw$2d
* @return Returns the page. R,Fgl2
*/ Vr/Bu4V"
public Page getPage(){ w2{g,A|
return page; D9BQID$R
} _ 5"+Dv
ZjD)?4
/** '^iUx,,ZQ
* @param content v^SsoX>WMH
* The content to set. ?^9BMQ+
*/ R4{-Qv#8
q
public void setContent(List content){ E1 |<Pt
this.content = content; "_< 9PM1t
} ?[)yGRzO2
>;4!O%F
/** vvq/
* @param page p|3b/plZ
* The page to set. NvJV</l6A
*/ 2.-o@im0
publicvoid setPage(Page page){ ?mx\eX{
this.page = page; -\#lF?fzb
} &gn-Wb?
} "uKFOV?j&
B+] D5K
E!J=8C.:
8#X_#
PLA#!$c7q
2. 编写业务逻辑接口,并实现它(UserManager, _c2WqQ-05
6e&$l-
UserManagerImpl) WC*=rWRxF
java代码: w^q7n
;3"@g]e
1J{fXh
/*Created on 2005-7-15*/ <T+!V-Pj*
package com.adt.service; &!L:"]=+
P4k;O?y
import net.sf.hibernate.HibernateException; #.._c?%4/
Y$<D9fs3
import org.flyware.util.page.Page; pKT2^Q}-h
y('k`>C
import com.adt.bo.Result; RWKH%C[Yd
FhkkWWL
/** +G*JrwJ&=
* @author Joa c_.-b=zm
*/ ""% A'TZ
publicinterface UserManager { 3qaMO#{M
''H"^oS
public Result listUser(Page page)throws YoKs:e2/:
$q_R?Eay
HibernateException; %m&@o~+
0uvzxmN
} 8wK ~
i
Kj3?ve~
t"vRc4mf
$s-Y%gc
PuL<^aJ
java代码: G[,Q95`w?<
X~oK[Nf'9
S($Su7g%_
/*Created on 2005-7-15*/ 0 1V^L}
package com.adt.service.impl; iW%8/$
V}WB*bE
import java.util.List; xQ4%e[/
Hfym30
import net.sf.hibernate.HibernateException; N&,]^>^u
o!c]
(
import org.flyware.util.page.Page; ?K_
'@
import org.flyware.util.page.PageUtil; pH@]Y+W
0bS|fMgc
import com.adt.bo.Result; mGjN_
import com.adt.dao.UserDAO; ?r=jF)C<'
import com.adt.exception.ObjectNotFoundException; r(h`XMsU
import com.adt.service.UserManager; aEt/NwgiQ
5jB*fIz
/** UUc8*yU)
* @author Joa ?jx1R^
*/ p-GAe,2q
publicclass UserManagerImpl implements UserManager { T;5r{{
#,d I$gY
private UserDAO userDAO; ntVS:F
vBcq_sbo
/** Pe;Y1Qq>>
* @param userDAO The userDAO to set. 3qL>-%):*
*/
z4X}O
{
publicvoid setUserDAO(UserDAO userDAO){ $za8"T*I
this.userDAO = userDAO; oU*45B`"
} G\de2Q"d:O
r|u MovnV
/* (non-Javadoc) FRu]kZv2
* @see com.adt.service.UserManager#listUser ' o_:^'c
P!G858V(
(org.flyware.util.page.Page) 0Hxmm@X2
*/ jho**TQ P
public Result listUser(Page page)throws Om;&_!i
!%)F J:p
HibernateException, ObjectNotFoundException { $D'-k]E[H
int totalRecords = userDAO.getUserCount(); (Qo I<j""
if(totalRecords == 0) ZyrI R
throw new ObjectNotFoundException (xHf4[[u
9H-|FNz?c
("userNotExist"); %a+mk
E
page = PageUtil.createPage(page, totalRecords); G+UMBn
List users = userDAO.getUserByPage(page); \R36w^c3
returnnew Result(page, users); ?L&'- e@
} .Z:zZ_Ev
H,nec<Jp
} o%9*B%HO/
{(U %i\F\
{!t7[Ctb
eq(am%3~
fk1ASV<rN
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ojvj}ln
'(bgs
询,接下来编写UserDAO的代码: ?T9(Vw
3. UserDAO 和 UserDAOImpl: .sC?7O=
java代码: (8.Z..PH
.qMOGbd?
Oy U
/*Created on 2005-7-15*/ ~T&<CTh
package com.adt.dao; l&iq5}[n&
s7Ub@
import java.util.List; 6f')6X'x
"#[!/\=?:
import org.flyware.util.page.Page; MjlP+; !
$YN6<5R)
import net.sf.hibernate.HibernateException; ),G= s Oo
#wL
/** 'EDda
* @author Joa h$4Hw+Yxs]
*/ h%}/Cmx[
publicinterface UserDAO extends BaseDAO {
A);
mEw ~yOW]M
publicList getUserByName(String name)throws X.hm s?]
vnWWneeNr
HibernateException; 8"sb;
uwz)($~bp
publicint getUserCount()throws HibernateException; <Utnz)
B2-V@06
publicList getUserByPage(Page page)throws K+;e4_\
q#<^ ^4U
HibernateException; 0 stc9_O
9E>xIJ@J2T
} ='`/BY(m[
O8B\{T1
&f^, la
=-IbS}3
tjupJ*Rt
java代码: C:PMewn
O3I8k\`
uc;8 K,[t
/*Created on 2005-7-15*/ n4}Br;%
package com.adt.dao.impl; ?b(=1S\E'^
?VP8ycm
import java.util.List; N5a*7EJv+
?OkWe<:4
import org.flyware.util.page.Page; sBr_a5QQ#
vI>>\.ED
import net.sf.hibernate.HibernateException; .zi_[
import net.sf.hibernate.Query; o4|M0
!o:f$6EA~C
import com.adt.dao.UserDAO; ]H`1F1=
6@rMtQfI
/** XUz3*rfs
* @author Joa bD/~eIcWL
*/ 3AU;>D ^5
public class UserDAOImpl extends BaseDAOHibernateImpl Kx>qz.wwI?
9WyAb3d'
implements UserDAO { mIK7p6
L*YynF
/* (non-Javadoc) a!=D [Gz*5
* @see com.adt.dao.UserDAO#getUserByName "wNJ
9I}-[|`u
(java.lang.String) Zl^\Q=*s
*/ etTn_v
publicList getUserByName(String name)throws r>o63Q:
#"@|f
HibernateException { *MKO
I'
String querySentence = "FROM user in class OCNQvF~
G"h'_7
com.adt.po.User WHERE user.name=:name"; 03q5e
Query query = getSession().createQuery <
jJ
OX\A|$GS
(querySentence); I}1NB3>^
query.setParameter("name", name); wOU_*uY@6'
return query.list(); f|\onHI)>
} C{U?0!^
&5yVxL:
/* (non-Javadoc) <g"{Wv: h
* @see com.adt.dao.UserDAO#getUserCount() W"k"IvTW}
*/ %5(I/zB
publicint getUserCount()throws HibernateException { jYk&/@`Ly
int count = 0; Dfmjw
String querySentence = "SELECT count(*) FROM hb}+A=A=+
g:hjy@ w
user in class com.adt.po.User"; 5>[u `
Query query = getSession().createQuery Z&1\{PG3*
qm/)ku0
(querySentence); ,U2*FZ["
count = ((Integer)query.iterate().next 'Gj3:-xqL
9Z4nAc
()).intValue(); ]n6#VTz*
return count; ]s<[D$ <,
} OCe!.`
fU/>z]K
/* (non-Javadoc) )Y"+,$$>Y`
* @see com.adt.dao.UserDAO#getUserByPage EV]1ml k$
hgPa6Kd
(org.flyware.util.page.Page) ;ub;lh 3
*/ HiZ*+T.B
publicList getUserByPage(Page page)throws G?O1>?4C
nT7%j{e=L
HibernateException { r>>%2Z-P
String querySentence = "FROM user in class T&6l$1J
|fK1/<sz#
com.adt.po.User"; Te"ioU?.
Query query = getSession().createQuery $a.JSXyxL
h9}+l
(querySentence); Hj^1or3R]
query.setFirstResult(page.getBeginIndex()) ]Sf]J4eQ
.setMaxResults(page.getEveryPage()); -t!~%_WCv
return query.list(); (A9Fhun
} 0X6YdW _2X
J')o|5S1N
} geru=7
LBYMCY
m*&]!mM"0G
o#3ly-ht
]_f_w9]
至此,一个完整的分页程序完成。前台的只需要调用 |d{PA.@33
D4eDHq
userManager.listUser(page)即可得到一个Page对象和结果集对象 Q /U2^
$V-~Bu-
的综合体,而传入的参数page对象则可以由前台传入,如果用 gb[5&>(#
M?1Y,5
webwork,甚至可以直接在配置文件中指定。 =^M/{51j
L/$H"YOv
下面给出一个webwork调用示例: %O|iE M
java代码: Ag-(5:
, qMzWa
fK>L!=Q
/*Created on 2005-6-17*/ 1m4$ p2j
package com.adt.action.user; ~!B\(@GU
@LF,O}[2J
import java.util.List; R0KPZv-
.s?L^Z^
import org.apache.commons.logging.Log; PxvyN_B#>
import org.apache.commons.logging.LogFactory; P)Jgs
import org.flyware.util.page.Page; L+b6!2O,
,0M_Bk"
import com.adt.bo.Result; V(H1q`ao9
import com.adt.service.UserService; )}Hpi<5N
import com.opensymphony.xwork.Action; B-*+r`@Bd
Vh|*p&
/** ^UP`%egR
* @author Joa *7uH-u"5d
*/ ZF!h<h&,
publicclass ListUser implementsAction{ 9 P l
Wf+cDpK
privatestaticfinal Log logger = LogFactory.getLog $0W|26;
g2+2%6m0
(ListUser.class); n1Yp1"2b[
h79}qU
private UserService userService; Ouk^O}W6
q}3`|'3
private Page page; Kg{+T`
is?{MJZ_
privateList users; 4>wP7`/+y
R$R *'l
/* !z\h|wU+
* (non-Javadoc) 8SMxw~9$
* {5Q!Y&N.%
* @see com.opensymphony.xwork.Action#execute() owVX*&b{
*/ 8 ?xE6
publicString execute()throwsException{ )W^F2-{
Result result = userService.listUser(page); ju8>:y8
page = result.getPage(); 1KU!
tL
users = result.getContent(); Cwv9 a^
return SUCCESS; #|uCgdi
} )HEa<P^kJl
Ki;*u_4{
/** xK>*yV
* @return Returns the page. 3(>B Ke
*/ 1.}d.t
public Page getPage(){ A @i
return page; tm|ZBM
} z<MsKD0Q
tR#OjkvX
/** = }~hWL
* @return Returns the users. $zUP?Gq!
*/ KqHyG
publicList getUsers(){ em y[k
return users; bTI|F]^!
} ?e%ZOI
dn&s*
/**
{y)=eX9
* @param page CT&|QH{
* The page to set. b!+hH Hv:
*/ -M\<nx
publicvoid setPage(Page page){ 4j-Xi
this.page = page; x[cL
Bc<
} n'"/KS+_
zrvF]|1UP
/** AzPu)
* @param users QFA8N
* The users to set. G?yLo 'Ulo
*/ irZ])a
publicvoid setUsers(List users){ %[GsD9_-
this.users = users;
,>:U2%
} 2_>N/Z4T
{4l8}w
/** _?nL+\'V
* @param userService [|v][Hwv
* The userService to set. \P[Y`LYL
*/ VMZMG$C
publicvoid setUserService(UserService userService){ sWhZby7
this.userService = userService; QL(n} {.%
} Lw1Yvtn
} !n`fTK<$
&<z1k-&!
8C40%q..
d z|or9&
-uS!\
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, &bS,hbD t
<NMEGit
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 b1cy$I
#`^}PuQ
么只需要: (&r.w
java代码: [+^1.N
@@f"%2ZR[
"MeVE#O
<?xml version="1.0"?> -abt:or
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork x[p|G5
KR}?H#%
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 9+|$$)
KM,\
1.0.dtd"> }PlRx6r@
poE0{HOU
<xwork> ~g91Pr
#<fRE"v:Q
<package name="user" extends="webwork- /PVk{3
i$Ul(?
interceptors"> cZ,b?I"Q%
Xg6Jh``
<!-- The default interceptor stack name soxc0OlN
yxPazz
--> 2Ah#<k-gC;
<default-interceptor-ref {p2!|A&a
+|3@=.V
name="myDefaultWebStack"/> }dX*[I
AI2)g1m
<action name="listUser" <sbu;dQ`
)$2QZ
qX
class="com.adt.action.user.ListUser"> h4gXvPS&r
<param hPkp;a #
=IZT(8
name="page.everyPage">10</param> '@v\{ l
<result L(6d&t'|-R
%uDi#x.
name="success">/user/user_list.jsp</result> gT.sjd
</action> C[cbbp
>>r(/81S
</package> yX>K/68
,>a&"V^k
</xwork> WCZjXDiwJ
LBeF&sb6
k t#fMd$
u[;\y|75
Q-oktRK
xK[ou'
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Oi.C(@^(
tAd%#:K
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ,L2ZinU:
P8:dU(nlW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |l^uEtG
b#%hY{$j
7~h<$8Y(T
C^Yb\N}S
-m zIT4
我写的一个用于分页的类,用了泛型了,hoho u{cW:
QT5TE: D
java代码: a=_g*OK}D
o'aEY<mZ7
QE+g
j8
package com.intokr.util; &&8x%Pml
!qQl@j O
import java.util.List; )u&|_&g{}J
d'gfQlDny
/** nF]W,@u"h
* 用于分页的类<br> R_cA:3qc~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> x;KOqfawv
* AR%4D3Dma
* @version 0.01 Tk[ $5u*,
* @author cheng p$c6<'UqH
*/ e)k9dOR
public class Paginator<E> { _yx>TE2e
privateint count = 0; // 总记录数 *KF#'wi
privateint p = 1; // 页编号 e2Pcm_Ahv*
privateint num = 20; // 每页的记录数 _Ay9p[l
privateList<E> results = null; // 结果 |3b^~?S
r|8d
4
/** cl3K<'D
* 结果总数 a.\:T,cP>
*/ 3ZPWze6
publicint getCount(){ sE<V5`Z=
return count; $rBq"u=,0+
} Pj^{|U2 1
Mj3A5;#
publicvoid setCount(int count){ h2A <" w
this.count = count; qA7>vi%
} k"%~"9
K7B/s9/xs
/** |Zpfq63W
* 本结果所在的页码,从1开始 ,-LwtePJ0
* +o{R _
* @return Returns the pageNo. M/'sl;
*/ >>)b'c
publicint getP(){ O63<AY@
return p; 2wg5#i
} |A~jsz6pI
~W'{p
/**
x+:UN'"r
* if(p<=0) p=1 d"mkL-
* =o(5_S.u;
* @param p 9&2O9Nz6
*/ IMFDM."s
publicvoid setP(int p){ t|\%VC
if(p <= 0) I*{nP)^9
p = 1; T*Exs|N2P-
this.p = p; LmrfN?5
} myQagqRx
~H_/zK6e
/** nNV'O(x}
* 每页记录数量 =:Fc;n>c<K
*/ Fnv;^}\z
publicint getNum(){ %N6A+5H
return num; ~
'cmSiz-
} xh,qNnGGi
Lx1FpHo
/** ,kGc]{'W
* if(num<1) num=1 `2WFk8) F
*/ )[6U^j4
publicvoid setNum(int num){ ZY= {8T@
if(num < 1) <?6|.\&
num = 1; #U4F0BdA
this.num = num; Gr'
CtO
} 1CD+B=pQG
h 8S. x)
/** 4r#= *
* 获得总页数 85$m[+md
*/ 8I?Wt
W
publicint getPageNum(){ bdrg(d6
return(count - 1) / num + 1; S~bOUdV
Z
} .t-4o<7 3
VBGuC c/
/** 6Q@j
* 获得本页的开始编号,为 (p-1)*num+1 G@\1E+Ip
*/ $y &E(J
publicint getStart(){ BwGfTua
return(p - 1) * num + 1; Id'-&tYG
} 'Cfl*iNb
Wx}8T[A}
/** X1|njJGO1
* @return Returns the results. DB|Y
*/ \)N9aV
publicList<E> getResults(){ ,j{,h_Op
return results; ) 1f~ dR88
} Q#X8u-~
Dlae;5D
public void setResults(List<E> results){ AaOuL,l
this.results = results; F?*-4I-
} M61xPq8y5
Su7?;Oh/yI
public String toString(){ S>6~lb8G
StringBuilder buff = new StringBuilder L|:`^M+^w
.-c4wm}
(); [Cz-i
buff.append("{"); Q5`*3h6p=
buff.append("count:").append(count); kQSy+q
buff.append(",p:").append(p); /QWvW=F2<
buff.append(",nump:").append(num); ay
;S4c/_
buff.append(",results:").append 5E;qM|Ns
.CABH,Po:
(results); VcO0sa f`
buff.append("}"); 61>.vT8P
return buff.toString(); EStB#V^
} g`' !HGY
mbxZL<ua
} C.yQ=\U2
HGs $*
b\kdKVh&