Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 JZrZDW>M
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^;mGOjS
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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 Et"B8@'P
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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 4
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分页支持类: Ha!]*wg#
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java代码: :P\RiaZAT
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package com.javaeye.common.util; kD4J{\
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import java.util.List; [YQ` `
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publicclass PaginationSupport { v>p~y u+G
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publicfinalstaticint PAGESIZE = 30; )@.6u9 \
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privateint pageSize = PAGESIZE; lJXihr
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privateList items; x5nw/''[2
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privateint totalCount; 1ml{oqNj
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privateint[] indexes = newint[0]; "+ 8Y{T
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privateint startIndex = 0; "0A !fRI~
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public PaginationSupport(List items, int 6
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totalCount){ !T8h+3I
setPageSize(PAGESIZE); 9^1.nE(R&
setTotalCount(totalCount); j.y8H
setItems(items); E6y ?DXWH
setStartIndex(0); 73d7'Fw
} i_qR&X
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public PaginationSupport(List items, int M8'
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totalCount, int startIndex){ ;b1*2-
setPageSize(PAGESIZE); !8i[.EAT
setTotalCount(totalCount); Sg}]5Mn`
setItems(items); aJ}Cqk
setStartIndex(startIndex); FrBJv<
} )o@-h85";
}CXL\,;
public PaginationSupport(List items, int FYu=e?L
ZAcW@xfb
totalCount, int pageSize, int startIndex){ By-A1|4Cp`
setPageSize(pageSize); !9JK95;
setTotalCount(totalCount); nd1%txIsr
setItems(items); ZSg["`
setStartIndex(startIndex); `(7HFq<N
} cu V}<3&
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publicList getItems(){ aI0}E O
return items; ^(8(z@y
} /iekww^54
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publicvoid setItems(List items){ c|^#v8x^/
this.items = items; %.*?i9}
} n9Xs sl0
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publicint getPageSize(){ vg/:q>o
return pageSize; @`6db
} a\m@I_r.N
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publicvoid setPageSize(int pageSize){ Tp0^dZ M+
this.pageSize = pageSize; zf>r@>S!L
} :.
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publicint getTotalCount(){ ?YO$NYwE
return totalCount; zg=F;^oZ<
} SXx2
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publicvoid setTotalCount(int totalCount){ WhHnF*I
if(totalCount > 0){ a D,(mw-7r
this.totalCount = totalCount; h5?yrti
int count = totalCount / /"M7YPX;
-K K)}I`
pageSize; `II/nv0jn
if(totalCount % pageSize > 0) L:g!f
count++; $|yO
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indexes = newint[count]; ywRwi~
for(int i = 0; i < count; i++){ \D37l_
indexes = pageSize * ]7`)|PJ
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i; mnM!^[|z
} *[eh0$
}else{ ,mE*k79L6
this.totalCount = 0; P`K?k<
} &91U(Go
} k*8
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publicint[] getIndexes(){ loLN
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return indexes; :>K=kZ=k
} Ws;}D}+
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publicvoid setIndexes(int[] indexes){ aBO%qmtt
this.indexes = indexes; MWS=$N)v*
} 5`B!1
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publicint getStartIndex(){ mGmkeD'
return startIndex; PfI~`ke
} .7*3V6h =F
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publicvoid setStartIndex(int startIndex){ Q( C\X
if(totalCount <= 0) prC1<rm
this.startIndex = 0; JPX5Jm()
elseif(startIndex >= totalCount) *@|EaH/
this.startIndex = indexes :Sx!jx>W
)PU?`yLTr
[indexes.length - 1]; av&4:O!
elseif(startIndex < 0) K0i[D"
this.startIndex = 0; D4x~Vk%H
else{ wh\J)pA1
this.startIndex = indexes $~V,.RD
' ju{j`b
[startIndex / pageSize]; Rmrv@.dr!
} >!vb ;a!
} B!=JRfT
y/ #{pyJ
publicint getNextIndex(){ *jps}uk<
int nextIndex = getStartIndex() + Vn`-w
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pageSize; {:VUu?5-t;
if(nextIndex >= totalCount) (YbRYu
return getStartIndex(); S[bFS7[
else j#TtY|Po
return nextIndex; \B'rWk33,
} 1%YjY"j+
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publicint getPreviousIndex(){ Khbkv
int previousIndex = getStartIndex() - ab 1qcQ<
.cTK\
pageSize; R(c:#KF#8
if(previousIndex < 0) d85\GEF9i
return0; r?s,
else 8\BCC1K
return previousIndex; `3Gjj&c
} ,1"w2, =
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} :RsO$@0G
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抽象业务类 2l)J,z
java代码: K +oFu%
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/** qsjTo@A
* Created on 2005-7-12 eGZX6Q7m
*/ FF"6~
package com.javaeye.common.business; +X4O.6Mn
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import java.io.Serializable; qHGXs@*M&
import java.util.List; y`?{2#1H
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import org.hibernate.Criteria; tdTD!'
import org.hibernate.HibernateException; *^XfEO
import org.hibernate.Session; "x.|'
import org.hibernate.criterion.DetachedCriteria; LLn,pI2fL{
import org.hibernate.criterion.Projections; fX,L;Se"
import 6B)3SC
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org.springframework.orm.hibernate3.HibernateCallback; =(f+geA"hm
import 'E2\e!U/
(~~*PT-
org.springframework.orm.hibernate3.support.HibernateDaoS !%' 1x2?
=v4;t'_^
upport; qW57h8M
mJ=3faM
import com.javaeye.common.util.PaginationSupport; pSQ)DqW
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public abstract class AbstractManager extends uaMf3HeYV
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HibernateDaoSupport { 7Vf2Qx1_
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privateboolean cacheQueries = false; c?qg
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privateString queryCacheRegion; CKShz]1
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publicvoid setCacheQueries(boolean B!|<<;Da6
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cacheQueries){ -jc8ku3*
this.cacheQueries = cacheQueries; 2\flTO2Ny
} ;\@co5.=
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publicvoid setQueryCacheRegion(String =Rl?. +uE
), >jBYMJ
queryCacheRegion){ 7tOOruiC
this.queryCacheRegion = |s&jWM$
sh []OSM
queryCacheRegion; `C~RA,M
} z~TG~_s
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publicvoid save(finalObject entity){ SF.4["$
getHibernateTemplate().save(entity); s)#8>s -
} {{b&l!
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publicvoid persist(finalObject entity){ C9-IJj
getHibernateTemplate().save(entity); \{F{yq(
} u~#QvA~]
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publicvoid update(finalObject entity){ 9$&+0
getHibernateTemplate().update(entity); cPh
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} 9Foo8e
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publicvoid delete(finalObject entity){ Byf5~OC
getHibernateTemplate().delete(entity); ;[*jLi,uc
} @1#QbNp#
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publicObject load(finalClass entity, S/}6AX#F4
:DP%>H|
finalSerializable id){ B3V:? #
return getHibernateTemplate().load o8+ZgXct
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(entity, id); %vjLw`
} Mg
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publicObject get(finalClass entity, `8Y& KVhu
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finalSerializable id){ aa8xo5tIp
return getHibernateTemplate().get (fmcWHs
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(entity, id); CmaV>
} k!e \O> +
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publicList findAll(finalClass entity){ I^iJ^Z]vx
return getHibernateTemplate().find("from F+A"-k_\T#
X {,OP/
" + entity.getName()); PI>PEge!&
} ?CB*MWjd
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publicList findByNamedQuery(finalString %G6ml,
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namedQuery){ S<"M5e
return getHibernateTemplate nQuiRTU<
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().findByNamedQuery(namedQuery); 0be1aY;m&
} 8spoDb.S
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publicList findByNamedQuery(finalString query, I@VhxJh
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finalObject parameter){ }mRus<Ax
return getHibernateTemplate >
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().findByNamedQuery(query, parameter); xaO9?{O
} TJ@@kSSbl
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publicList findByNamedQuery(finalString query, rzJNHf=FVY
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finalObject[] parameters){ @OOnO+g
return getHibernateTemplate %c%0pGn8-
=[8EQdR
().findByNamedQuery(query, parameters); BZy&;P
} V eO$n*O
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publicList find(finalString query){ ?bc-?<Xk
return getHibernateTemplate().find )X{ x\
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(query); T9r"vw
} -"qw5Y_oF?
7;dTQ.%n
publicList find(finalString query, finalObject Fj\}&H*+
%,$Ms?,n`
parameter){ 7a_pO1MBL
return getHibernateTemplate().find |;2Y|>=
{UpHHH:X#
(query, parameter); -<kl d+
}
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public PaginationSupport findPageByCriteria zx"'WM*
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(final DetachedCriteria detachedCriteria){ /C(lQs*l
return findPageByCriteria zoXCMBg[
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); x\t)uM%
} dkTj
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public PaginationSupport findPageByCriteria pKDP1S#<
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(final DetachedCriteria detachedCriteria, finalint ok;Y xp>
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startIndex){ 7Iu^l4=2
return findPageByCriteria [:gPp)f,
}X{#=*$GQ
(detachedCriteria, PaginationSupport.PAGESIZE, 3-cCdn
b_=$W
startIndex); +jzwi3B`
} O]{3aMs!Y
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public PaginationSupport findPageByCriteria IXb]\ )
} ).rD
(final DetachedCriteria detachedCriteria, finalint mG4myQ?$
,at"Q$)T
pageSize, n<
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finalint startIndex){ 5wM*(H^c[
return(PaginationSupport) juQ&v>9W)
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getHibernateTemplate().execute(new HibernateCallback(){ ylm*a74-X
publicObject doInHibernate zbH Nj(~
*,$cW,LN
(Session session)throws HibernateException { 9(?9yFbj5
Criteria criteria = Cz=HxU80J
E$5)]<p! <
detachedCriteria.getExecutableCriteria(session); >ZMB}pt`
int totalCount = 4;anoqiG\
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((Integer) criteria.setProjection(Projections.rowCount /DOV/>@5%
&u5OL?>
()).uniqueResult()).intValue(); hE>ux"_2/
criteria.setProjection y<7C!E#b8
Ay7I_"%
(null); }*.S=M]y$
List items = e~tgd8a2a
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criteria.setFirstResult(startIndex).setMaxResults 4W7
i#/,Q1yEn
(pageSize).list(); 2NS(;tBB0
PaginationSupport ps = 'n`+R~Kkh
aRSGI ja<L
new PaginationSupport(items, totalCount, pageSize, uC{qaMQ
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startIndex); -2NXQ+m ;
return ps; >B)&mC$$S
} oRl~x^[%[-
}, true); [JAHPy=+w
} >TSPEvWc
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public List findAllByCriteria(final yuyI)ebC
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DetachedCriteria detachedCriteria){ hV5Aw;7C
return(List) getHibernateTemplate O
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().execute(new HibernateCallback(){ USgZ%xk2
publicObject doInHibernate V+#Sb
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(Session session)throws HibernateException { Tb~|p_;o
Criteria criteria = (,Zy2wr=
y/}[S@4uB
detachedCriteria.getExecutableCriteria(session); zrt \]h+
return criteria.list(); o+UCu`7e
} +O`3eP`u
}, true); Ore>j+
} +ZH-'l
A*d Pw.
public int getCountByCriteria(final }j=UO*|
r)Q/YzXx*
DetachedCriteria detachedCriteria){ |C:^BWrU*
Integer count = (Integer) 8<BYAHY^
#-76E
getHibernateTemplate().execute(new HibernateCallback(){ p;;4b@
publicObject doInHibernate USF9sF0l
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(Session session)throws HibernateException { ckR>ps[ u
Criteria criteria = L $R"?O7
}xZR`xP(
detachedCriteria.getExecutableCriteria(session); +NML>g#F~z
return e/+_tC$@p@
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criteria.setProjection(Projections.rowCount 1'.SHY|
+Sz%2Q
()).uniqueResult(); 0,~f"Dyqy
} iuxI$
}, true); $~x#Q?-y
return count.intValue(); &72
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} % zP]z
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用户在web层构造查询条件detachedCriteria,和可选的 x`7Ch3`4}
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9W^sq<tR
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PaginationSupport的实例ps。 UB%Zq1D|t
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ps.getItems()得到已分页好的结果集 jb0wP01R
ps.getIndexes()得到分页索引的数组 T@K=
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ps.getTotalCount()得到总结果数 ~_l@
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ps.getStartIndex()当前分页索引
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ps.getNextIndex()下一页索引 --S1p0
ps.getPreviousIndex()上一页索引 Sq#AnD6To
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %"<|u)E
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Q{+*F8%8V<
2@TgeV0Y[
一下代码重构了。 hc"l^a!7ic
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我把原本我的做法也提供出来供大家讨论吧: kSW=DE|#}
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首先,为了实现分页查询,我封装了一个Page类: F~bDA~
java代码: v,T:V#f^
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/*Created on 2005-4-14*/ }I}/e
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package org.flyware.util.page; a$=BX=
Ux[2 +Cf
/** KjWF;VN*[3
* @author Joa ,=_)tX^
* e>$d*~mwn
*/ Y"{L&H `
publicclass Page { Bb[WtT}=
WD/\f$4
/** imply if the page has previous page */ %fbV\@jDCX
privateboolean hasPrePage; s=S9y7i(R
q?R^~r
/** imply if the page has next page */ G3.*fSY$.<
privateboolean hasNextPage; i2+r#Hw#5R
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/** the number of every page */ .j
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privateint everyPage; $ol]G`+
?xa70Pb{;
/** the total page number */ eeVDU$*e=
privateint totalPage; /"+CH\)
E
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/** the number of current page */ UC
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privateint currentPage; *|gY7Av*
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/** the begin index of the records by the current |~K 5]
/b1+ ^|_
query */ ]iU8n (5f
privateint beginIndex; )])nd"E
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/** The default constructor */ =l)D$l
public Page(){ *&vlfH
@:dn\{Zsea
} k!Ym<RD%N
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/** construct the page by everyPage X!b+Dk
* @param everyPage 0dTHF})m
* */ qix$ }(P
public Page(int everyPage){ lGlh/B%
this.everyPage = everyPage; 'iM#iA8
} "L0Q"t:
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/** The whole constructor */ Z5j\ M
public Page(boolean hasPrePage, boolean hasNextPage, [S~/lm
YujR}=B!/
*M? [Gro/
int everyPage, int totalPage, \?D~&d,a=
int currentPage, int beginIndex){ ~xa yGk
this.hasPrePage = hasPrePage; 1^ijKn@6
this.hasNextPage = hasNextPage; a
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this.everyPage = everyPage; `<3%`4z/
this.totalPage = totalPage; uIy$|N
this.currentPage = currentPage; ~GLWhe-
this.beginIndex = beginIndex; =dT
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} }6'%p Bd
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/** HJi
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* @return WaPuJ5;e
* Returns the beginIndex. &wX568o
*/ Ia[4P8Z
publicint getBeginIndex(){ D03QisH=
return beginIndex; @tX8M[.eA
}
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Yu}[RXC(=
/** 4C#r=Uw`
* @param beginIndex eP|_
* The beginIndex to set. yMz dM&a!*
*/ }Ug O$1
publicvoid setBeginIndex(int beginIndex){ */APe#
this.beginIndex = beginIndex; p)qM{`]G\
} 1`sTGNo
,bxGd!&{Q
/** 4Uk\h gT0
* @return OcE,E6LD
* Returns the currentPage. e#AmtheZR
*/ aI\:7
publicint getCurrentPage(){ {UFs1
return currentPage; *`_2uBz
} BMo2t'L
H
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/** [ KDNKK
* @param currentPage Z?<&@YQS
* The currentPage to set. uhm3}mWv
*/ h:AB`E1
publicvoid setCurrentPage(int currentPage){ (F j"<
this.currentPage = currentPage; ~c=F$M^"c
} 0<XxR6w
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/** V}MRdt7
* @return Qp;FVUw9
* Returns the everyPage. ;0 4< 9i
*/ arc{:u.K
publicint getEveryPage(){ w.(?O;
return everyPage; U+Vb#U7;
} >|pN4FS
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/** ydTd.`
* @param everyPage Sc?q}tt^C
* The everyPage to set. (]nX:t
*/ Hva/C{Y
publicvoid setEveryPage(int everyPage){ Ftdx+\O_i&
this.everyPage = everyPage; %,+&Kl
I
} (@Kc(>(: Y
p=[SDk`
/** m@W>ku
* @return Eq=j+ch7
* Returns the hasNextPage. gle<{
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*/ 48,uO!
publicboolean getHasNextPage(){ 3ESrd"W=
return hasNextPage; /?1^&a
} d
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]m :Y|,:6
/** n= q7*<l
* @param hasNextPage d/[kky}
* The hasNextPage to set. :rU,7`sE/
*/ HF<h-gX
publicvoid setHasNextPage(boolean hasNextPage){ z~th{4#E;
this.hasNextPage = hasNextPage; e!ql8wbp
} LvCX(yjZ*
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/** &bigLe
* @return IQWoK"B
* Returns the hasPrePage. K8W99:v
*/ LMNmG]#!
publicboolean getHasPrePage(){ PVSz%"
return hasPrePage; t[ZGY,8
} }LY)FT4n
} J`cRDO
/** O Cnra
* @param hasPrePage UZ1Au;(|
* The hasPrePage to set. -'
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*/ _`.Q7
publicvoid setHasPrePage(boolean hasPrePage){ 3i#'osq
this.hasPrePage = hasPrePage; 2;x+#D8
} tHEZuoi
I9<%fv
/** @V Sr'?7-
* @return Returns the totalPage. :_h#A}8Xd
* Ek60[a
*/ q<K/q"0-l
publicint getTotalPage(){ NFPWh3),f
return totalPage; 1/v#Z#3[
} V0G[f}tm'
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/** w3&L 6|,
* @param totalPage &@ ${@
* The totalPage to set. 7M~/[f7Z{
*/ pM~-o?
publicvoid setTotalPage(int totalPage){ PU4-}!K
this.totalPage = totalPage; LKA/s ~G
} pjma<^|F
[@2$W?0i
} p||mR
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4Ik'beZqK
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 A6
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个PageUtil,负责对Page对象进行构造: z0UtKE^b
java代码: +~sqv?8
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/*Created on 2005-4-14*/ +p$lVnAt
package org.flyware.util.page; SX&Q5:
eCiI=HcW;
import org.apache.commons.logging.Log; L#S|2L_hC
import org.apache.commons.logging.LogFactory; CaVVlL
%LuA:{EVD
/** M^lP`=sSv
* @author Joa oPVt
qQ
* r^{Bw1+
*/ B=%x#em
publicclass PageUtil { 7nsovWp
UjMWSPEBy
privatestaticfinal Log logger = LogFactory.getLog #|T2`uYotf
0lOR.}]q
(PageUtil.class); xUTTRJ(\
cdN =HM~I
/** '.jYu7
* Use the origin page to create a new page dK4w$~j{k
* @param page lqmr`\@)
* @param totalRecords Ir=G\/A
* @return G E? \Vm
*/ `lrNH]B
publicstatic Page createPage(Page page, int r]U8WM3r
w&e3#p
totalRecords){ wB:<ICm
return createPage(page.getEveryPage(), nX\mCO4T
3"sXN)j
page.getCurrentPage(), totalRecords); FF;Fo}no-
} '<>?gE0Cd
;/H/Gn+
/** ~[f`oC
* the basic page utils not including exception Er
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7*
[
handler N( f0,
* @param everyPage %j2$ ezud
* @param currentPage 3#Iq5vT
* @param totalRecords YABi`;R]'
* @return page de;CEm<n
*/ Vt,P.CfdC
publicstatic Page createPage(int everyPage, int !N!AO(Z
)Cat$)I#,
currentPage, int totalRecords){ 13*S<\
everyPage = getEveryPage(everyPage); D]5j?X'
currentPage = getCurrentPage(currentPage); aj/+#G2
int beginIndex = getBeginIndex(everyPage, ?6HnN0A)
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currentPage); >nvnU`\
int totalPage = getTotalPage(everyPage, +"1-W>HV
(g&@E(@]?
totalRecords); T^{=cx9x9
boolean hasNextPage = hasNextPage(currentPage, ]u:_r)T
C=IN "
totalPage); s< Fp17
boolean hasPrePage = hasPrePage(currentPage); ,LC(Ax'.F
-<sW`HpD'
returnnew Page(hasPrePage, hasNextPage, yYP>3]z
everyPage, totalPage, %
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currentPage, dn:\V?9
K=r~+4F
beginIndex); 9m\Yi
} rHuzGSX54
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privatestaticint getEveryPage(int everyPage){ wEN[o18{
return everyPage == 0 ? 10 : everyPage; #N%j9
} G:@1.H`
m# -&<=
privatestaticint getCurrentPage(int currentPage){ 7-C])9
return currentPage == 0 ? 1 : currentPage; QjD=JC+
} j WMTQLE.
*Vg) E*s
privatestaticint getBeginIndex(int everyPage, int :G]t=vr1
;.b^&h
currentPage){ {;6a_L@q;|
return(currentPage - 1) * everyPage; ;}M&fXFp"|
} Z[0/x.pp$
4Xww(5?3
privatestaticint getTotalPage(int everyPage, int ( uG;Q
m&z(2yb1
totalRecords){ '=eVem=
int totalPage = 0; fJ6Q:7
$*LBZcL
if(totalRecords % everyPage == 0) sZ7~AJ
totalPage = totalRecords / everyPage; j)#yyK{k2s
else 7j29wvSp5
totalPage = totalRecords / everyPage + 1 ; @1' Y/dCyD
EWY'E;0@5
return totalPage; ZE=
Yn~XM
} P,(_y8
g++-v HD
privatestaticboolean hasPrePage(int currentPage){ EEo I|
return currentPage == 1 ? false : true; _%23L|
} Mz86bb^J
VvT7v]
privatestaticboolean hasNextPage(int currentPage, iX WB
Ix<!0!
vk
int totalPage){ UoUQ6Ij
return currentPage == totalPage || totalPage == TtH!5{$s
#sk~L21A
0 ? false : true; 2E`mbT,v&
} =''b `T$
{oR@'^N
`M(st%@n
} !w@i,zqu
wAJ=rRI
)]4=anJu@|
u^#e7u
ZHlHnUo
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。 ~B?Wg!
2$`Y 4b 3t
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 zL3zvOhu}
`M. I.Z_
做法如下: %<'.c9u5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6eA)d#
I6gduvkXi4
的信息,和一个结果集List: YpRhl(|
java代码: jSRi
UX<)hvKj
pf+VYZ#)
/*Created on 2005-6-13*/ tkkh<5{C
package com.adt.bo; r .
(}
xI/8[JW*
import java.util.List; z.?slYe[
#0\* 86
import org.flyware.util.page.Page; k#7A@Vb
euW
/** ;t,v/(/3
* @author Joa N9y+Psh
*/ W-Vc6cq
publicclass Result { K5t.OAA:
E7_OI7C
private Page page; '#eT
)qOcx
I
private List content; H
SGz-
,A)Z.OWOq
/** ET 0(/Zz
* The default constructor -YmIRocx
*/ jzZ]+'t
public Result(){ 8OO[Le]1
super();
U0srwt97S
} &\Lu}t7Ru
ZLPj1L
/** c@)?V>oe
* The constructor using fields &%8IBT
* #};Zgixo$
* @param page };EB[n
* @param content jW-;Y/S
*/ 412E7
public Result(Page page, List content){ hE$3l+
this.page = page; ]mUt[Yy:z
this.content = content; fny6`_O
} M)AvcZNs
h@\HPYi#.
/** b!`Ze~V
* @return Returns the content. U~t!
*/ ]VE3u_kR
publicList getContent(){ 53pT{2]zAi
return content; s.n:;8RibP
} qDz[=6BF
Uj3HAu
/** @LDs$"f9=
* @return Returns the page. n2Mpo\2
*/ n:b,zssP
public Page getPage(){ :i@
$s/
return page; $b2~H+u(
} T!HAE#xC
:nc%:z=O
/** "r3h+(5
* @param content 3bjCa\ "
* The content to set.
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*/ 9
`q(_\ x
public void setContent(List content){ RrYNtc
this.content = content; H{Lt,#
} f5l\3oL
[p}~M-$V8Y
/** e"XolM0IM
* @param page .tyV=B:h
* The page to set. </?ef&
*/ 8G|?R#&
publicvoid setPage(Page page){ m({q<&]Qp
this.page = page; q;IuV&B
} C dPQhv)m
} Q2* 8c$
pSIXv%1J
Wa.!eAe}
E|SmvIV-
\Y!=O=za]
2. 编写业务逻辑接口,并实现它(UserManager, ,:MUf]Ky
NYs<`6P:Y
UserManagerImpl) o{n#f?EA
java代码: B,%KvL&xMX
OL:hNbw'~T
!?Y71:_!
/*Created on 2005-7-15*/ ua &uR7
package com.adt.service; 1/qD5 *`Y
8 ph1xQ'
import net.sf.hibernate.HibernateException; @ PhAg
-U?%A:,a|
import org.flyware.util.page.Page; NLYf
@~N"MsF3
import com.adt.bo.Result; -f1}N|hy
;X0uA?
/** ;:ZD<'+N
* @author Joa [;F!\B-
*/ <S6?L[_
publicinterface UserManager { hNgT/y8
!W0JT#0
public Result listUser(Page page)throws 7.g,&s%q
X%fLV(
HibernateException; S1'?"zAmd
_^zs(
} \yxGE+~P
3webAaO
$AMcU5^b7
Gv
}
},Grg~l
java代码: G{Ju2HY
DRXUQH
hb/Z{T'
/*Created on 2005-7-15*/ t7xJ"
package com.adt.service.impl; /d Ua
) .' + {
import java.util.List; *8yC6|wL?
YN:Sn\`D 8
import net.sf.hibernate.HibernateException; M
0RA&
B,Tv9(sv
import org.flyware.util.page.Page; *-q&~
import org.flyware.util.page.PageUtil; ]W~M?1}
!bnnUCTb\
import com.adt.bo.Result; H!6&'=c {k
import com.adt.dao.UserDAO; tI#65ox#
import com.adt.exception.ObjectNotFoundException; 2bw.mp&v1
import com.adt.service.UserManager; ;'Z"CbS+
-4F}I3I
/** xcQ^y}JN
* @author Joa D(dV{^} 9
*/ oY,{9H37b
publicclass UserManagerImpl implements UserManager { :J2^Y4l2
IDh`*F
private UserDAO userDAO; v@s"*E/PF7
Z.unCf3Q
/** Jcs
/i
* @param userDAO The userDAO to set. vQn hb%
*/ %]tW2s"
publicvoid setUserDAO(UserDAO userDAO){ k*F9&-rtN
this.userDAO = userDAO; iS"6)#a72
} I|c?*~7*
dXsL0r*c
/* (non-Javadoc) 6Rq +=X
* @see com.adt.service.UserManager#listUser mRGr+m
nKtRJ,>
(org.flyware.util.page.Page) {BaPK&x,
*/ =T?Xph{
public Result listUser(Page page)throws i??+5o@uTF
HxLuJ
HibernateException, ObjectNotFoundException { c*"P+
int totalRecords = userDAO.getUserCount(); !/|B4Yv
if(totalRecords == 0) Ag2Q!cq
throw new ObjectNotFoundException H/8u?OC
(R RRG;*n#
("userNotExist"); 6!*zgA5M'
page = PageUtil.createPage(page, totalRecords); j/E(*Hv
List users = userDAO.getUserByPage(page); J\'f5)k
returnnew Result(page, users); bS55/M w
} ^U,C])n
fmUrwI1 %
} ^r7KEeVD
.i` -t"
L/vw7XNrX
N#R8ez`
GU Mf}y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 9]tW; ?
9O^~l2`
询,接下来编写UserDAO的代码: G2@'S&2@s
3. UserDAO 和 UserDAOImpl: ]<q!pE;t
java代码: ["ocZ? x
`(O#$n
$,I@c"m{
/*Created on 2005-7-15*/ JEZ0O&_R
package com.adt.dao; ;4v`FC>
,,)'YhG(
import java.util.List; $I ,Np)i
P(C5@x(Z
import org.flyware.util.page.Page; Tpkt'|8
G#uB%:)&0u
import net.sf.hibernate.HibernateException; jC?l :m?
EF=5[$
u
/** 07ppq?,y
* @author Joa puEu)m^
*/ ^d(gC%+!u
publicinterface UserDAO extends BaseDAO { .O+,1&D5
&/otoAr(
publicList getUserByName(String name)throws _ph1( !H$
nU#K=e
=W
HibernateException; Gs04)KJm<
$h=v;1"
publicint getUserCount()throws HibernateException; vJx( lU`Y
(gcy3BX;
publicList getUserByPage(Page page)throws {\LLiU}MJC
?\X9Ei
HibernateException; l%yQ{loTh
f&] !;)
} "uyr@u0b
.=hVto[QC
_Vc4F_
TvRm 7
vn@sPT
java代码: /&c>*4)
Uhyf
cN\_1
/*Created on 2005-7-15*/ 7s}F`fjKP
package com.adt.dao.impl; 1h)K3cC
qpa}6JVQ+j
import java.util.List; ;~`/rh
V\
aouYPxA`
import org.flyware.util.page.Page; <fMQ#No
zP c54>f
import net.sf.hibernate.HibernateException; PVmePgF
import net.sf.hibernate.Query; "`Xbi/i
YNp-A.o
W@
import com.adt.dao.UserDAO; V%zo[A
0B~x8f
/** C}9|e?R[Rz
* @author Joa N7X(gh2h
*/ ,hT**(W
public class UserDAOImpl extends BaseDAOHibernateImpl ;2sP3!*
KWi|7z(L=
implements UserDAO { tejpY
'I r
/* (non-Javadoc) (4rHy*6
* @see com.adt.dao.UserDAO#getUserByName rj1%IzaXU^
AF{@lDa1h
(java.lang.String) RyWfoLc
*/ YnCuF0>
publicList getUserByName(String name)throws lf R}cx
`sd
H
q
HibernateException { V*@&<x"E
String querySentence = "FROM user in class ZHj7^y@P
@TzUcE
com.adt.po.User WHERE user.name=:name"; *ck'vV'@
Query query = getSession().createQuery rK'O 85)eU
("<4Ry.u
(querySentence); Fa #5a'}I
query.setParameter("name", name); iqsR]mab
return query.list(); a5w E{K
} ,E+\SBQS_
dXU6TCjU7
/* (non-Javadoc) ?]TtUoY=)F
* @see com.adt.dao.UserDAO#getUserCount() r -uu`=,
*/ D<*)^^
publicint getUserCount()throws HibernateException { lg^Lk\Y+re
int count = 0; I}]UQ4XJ
String querySentence = "SELECT count(*) FROM {D[z>I;D
hN!{/Gc|
user in class com.adt.po.User"; v.g Ai6
Query query = getSession().createQuery :e}j$vF
7sVO?:bj}
(querySentence); P(LiH
count = ((Integer)query.iterate().next DKl\N~{F
y'^b{q@
()).intValue(); /<o?T{z<-
return count; FJW,G20L
} R+Ug;r-[
T~?&hZ>
/* (non-Javadoc) m*KI'~#$%
* @see com.adt.dao.UserDAO#getUserByPage 1ZvXRJ)%
%F:; A
(org.flyware.util.page.Page) g12.4+
*/ fA ),^
publicList getUserByPage(Page page)throws /\E3p6\*
nD=N MqQ &
HibernateException { 1IK*j+%
String querySentence = "FROM user in class F 9q!Upr_+
LftGA7uGJ)
com.adt.po.User"; zq|NltK
Query query = getSession().createQuery ]l
SxX
(querySentence); iU#"G" &
query.setFirstResult(page.getBeginIndex()) }0OQm?xh
.setMaxResults(page.getEveryPage()); S*WLb/R2
return query.list(); x3nUKQtk:8
} 81)i>]
(>*L-&-
} &uf|Le4
x5M+\?I<2
Hig.` P
W/%9=g$m
D\DwBZ>
至此,一个完整的分页程序完成。前台的只需要调用 ~!/a gLwY
?H8dyQ5"
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]tmMk7
LvL2[xh%&
的综合体,而传入的参数page对象则可以由前台传入,如果用 7<X!Xok
lKS 2OOYC`
webwork,甚至可以直接在配置文件中指定。 : T qeVf
X*&Thmee
下面给出一个webwork调用示例: FbW$H]C$
java代码: ;i?R+T
iD>H{1 h
bj?=\u
/*Created on 2005-6-17*/ <J.q[fd1*
package com.adt.action.user; (Hs,Tj
'GLpSWL+*
import java.util.List; 6Z@T
/"mU(
\[wbJ
import org.apache.commons.logging.Log; Ghar
hJ>v
import org.apache.commons.logging.LogFactory; 6E_YUk?KW
import org.flyware.util.page.Page; =(v'8?--
zV"'-iP
import com.adt.bo.Result; <."
@H<-`*
import com.adt.service.UserService; LeNSjxB
import com.opensymphony.xwork.Action; m'uFj !
"@Qg]#]JH
/** !=6 \70lJ
* @author Joa @r\{iSg&g.
*/ q/qig5Ou
publicclass ListUser implementsAction{ h)z2#qfc
#E_<}o
privatestaticfinal Log logger = LogFactory.getLog #+|0 o-
U/h@Q\~U
(ListUser.class); STPRC&7;
Lw<.QMN%f
private UserService userService; ,z>w^_
1L=)93,M
private Page page; hOuHTo^
gE8>o:6)6:
privateList users; /.sho\a
isFxo,R9r
/* X-psao0tI`
* (non-Javadoc) y'O<*~C(X
* @\a~5CLN
* @see com.opensymphony.xwork.Action#execute() U+!&~C^y
*/ WDt 6{5T
publicString execute()throwsException{ *0<)PJ T
Result result = userService.listUser(page); F]s:`4
page = result.getPage(); x1}Ono3"T
users = result.getContent(); 6S0Gjekr
return SUCCESS; ;f)AM}~^Q
} c Ze59
kX+98?h-C
/** aF>&X-2
* @return Returns the page. 9VSi2p*
*/ q*cEosi'F?
public Page getPage(){ r^ABu_u(`I
return page; 0:B%,nUM
} Sar1NkD#
Xx\,<8Xn
/** S,vdd7Y
* @return Returns the users. rCb#E}
*/ (D{J|
publicList getUsers(){ (ki= s+W-
return users; 0!tuUn
} rU1Ri
ACpecG
/** Ep3I*bQ
Y
* @param page f85~[3
J
* The page to set. eDvh3Y<D
*/ }^^c/w_
publicvoid setPage(Page page){ "+Sq}WR
this.page = page; _z9~\N/@[
} F6C7k9
XCO8A\
/** "akAGa!V+
* @param users Zx7aae_{
* The users to set. c6SXz%'k
*/ jINI<[v[
publicvoid setUsers(List users){ )UyJ.!Fly
this.users = users; ,T;D33XV
} zMd><UQP{
%Hhk
6tR,
/** Ty7)j]b"zl
* @param userService RF~G{wz
* The userService to set. 0?O_]SD
*/ 2IGU{&s
publicvoid setUserService(UserService userService){ s d = bw
this.userService = userService; d]N_<@tx9
} }c>vk
} >P//]nn
xC}' "``s
@#;*e] 1a
\C4wWh-A
pWP1$;8
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, <qEBF`XP =
:[0)Uu{
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 9~jS_Y)"
-<M+ $hK\
么只需要: "bQi+@
java代码: k;)mc+ ~+
w^,Xa
WZh_z^rwn
<?xml version="1.0"?> '`f+QP=`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ($W%&(:/
}>V=J aG
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *zW]IQ'A
Ex
skd}
1.0.dtd"> .L]5,#2([
[(&aVHUj
<xwork> qk(bA/+e
u7j,Vc'~
<package name="user" extends="webwork- $\bVu2&I
VN'\c3;
interceptors"> S(CVkCP
NytodVZ'3
<!-- The default interceptor stack name 1GB]Yi[>
16 \)C/*
--> Q>cE G"
<default-interceptor-ref $: |`DCC
-eIo
name="myDefaultWebStack"/> 7>0u
N|
)d2:r 07a
<action name="listUser" 8=zREt<Se
oXN(S:ZF
class="com.adt.action.user.ListUser"> ]>%2,+5
<param 3i'01z
VL'wrgk
name="page.everyPage">10</param> {3kz\FS
<result w0vsdM;G
uZ'Z-!=CL
name="success">/user/user_list.jsp</result> xEeHQ7J
</action> Rw FA
.k
+>T*c{
</package> radP%W-U
UBk:B
</xwork> c;06>1=wP5
OK YbEn#
t1yOAbI
)VqPaKZl
E'5KJn;_7
3d4A~!Iz
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 l-S0Gn/'X
~*<`PD O?
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 9Oo`4
GlRjbNW?Q
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 yPs6_Qo!p
>Gk<a
po,Ue>n/
%[M0TE=J
J9DI(`
我写的一个用于分页的类,用了泛型了,hoho {9.UeVz
3IB9-wG
java代码: S8v?H|rm
p
.P#S
&m
GU
package com.intokr.util; x'..j5
%Lb
cwh(9
import java.util.List; d|9]E&;,
c2fSpvz
/** B& R?{y*
* 用于分页的类<br> ;[[6[i
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #8ltV`
* jZ:/d!$S
* @version 0.01 $5&~gHc,
* @author cheng "*N#-=MJF
*/ $ #2<f 6
public class Paginator<E> { FQ`1c[M@
privateint count = 0; // 总记录数 "Z;({a$v
privateint p = 1; // 页编号
-$I30.#
privateint num = 20; // 每页的记录数 HavlN}h
privateList<E> results = null; // 结果 q-uzu !
PAtv#)h
/** `~"'\Hw
* 结果总数 :@ VC Kq!
*/ ,S(s
publicint getCount(){ 5MD'AP:
return count; 5??}9
} ysl#Rwt/2
s S#/JLDx]
publicvoid setCount(int count){ 3}&3{kt
this.count = count; DHx&%]r;D
} 4[MTEBx
kv, !"<
/** M_.Jmh<&&
* 本结果所在的页码,从1开始 m%>}T75C^
* ^cSfkBh
* @return Returns the pageNo. $Bl51VjN
*/ UnYb}rF#%
publicint getP(){ O>a1S*mxP
return p; ccPWfy_
} + G[zE
t u{~:Z(
/** s/s&d pT*
* if(p<=0) p=1 =Y6W
Qf
* '5[(QM5Gi&
* @param p 47Bg[
*/ +PI}$c-|`
publicvoid setP(int p){ ~{5va
if(p <= 0) nvXjW@)`
p = 1;
.=t:Uy
this.p = p; {;& U5<NO
} ~gGkw#
}1~9i'o%Z
/** #N>66!/V
* 每页记录数量 "::2]3e
*/ )oz2V9X{
publicint getNum(){ &GJVFr~z
return num; F;h^o !W7r
} |YyNqwP`,
un -h%-e|
/** Ql l{;A
* if(num<1) num=1 5(hv|t/a
*/ x=Oy 6"
publicvoid setNum(int num){ D1 v0`od'
if(num < 1) -PGxG 8S
num = 1; S-Vj$asv!
this.num = num; jgG9?w)|u
} 8F`8=L NO
^B}m~qT
/** .Y?]r6CC/
* 获得总页数 ruB D
^-
*/ g<M!]0OK
publicint getPageNum(){ a`#lYM%(>
return(count - 1) / num + 1; nGYimRYO
} TNA7(<"fV|
qm:C1#<p
/** ~D4l64
* 获得本页的开始编号,为 (p-1)*num+1 yt5<J-m
*/ eI2HTFyT
publicint getStart(){ 9X;*GC;d
return(p - 1) * num + 1; ]H}2|~c
} aGi`(|shW
|m"Gr)Gm
/** ?Z?(ky!
* @return Returns the results. x 4L3Z__
*/ q{f\_2[
publicList<E> getResults(){ >(.|oT\Tb
return results; =#y;J(>~|
} PQSmBTs.
KA?%1s(kJ
public void setResults(List<E> results){ sCrP+K0D
this.results = results; OW\vbWX
} 87+fd_G
=mZYBm,IQ
public String toString(){ Y:,C_^$w;
StringBuilder buff = new StringBuilder #Pf<2S
<4vCx
(); JJ_Z{
buff.append("{"); ~S;-sxoO0l
buff.append("count:").append(count); Q>Z~={"
buff.append(",p:").append(p); gH'hA'
buff.append(",nump:").append(num); jI*@&3
buff.append(",results:").append
3x+=7Mg9
2sk7E'2(
(results); ``:[Jr&
buff.append("}"); NQ 6oyg@&
return buff.toString(); TaHcvjhR
} LDHu10l
\ f+;X
} 'r%(,=L
7I"~a<f0X`
5o>`7(t`