Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 h$_Wh(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Jb#*QJ=
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 PnJr
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Pv1C o:
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分页支持类: t^)q[g
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java代码: Yc3r3Jy
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package com.javaeye.common.util; Vrf2%$g
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import java.util.List; no?TEXp*
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publicclass PaginationSupport { +M/04
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publicfinalstaticint PAGESIZE = 30; ?<YtlqL
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privateint pageSize = PAGESIZE; 7v}4 Pl,$4
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privateList items; 2^Tj7@
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privateint totalCount; h6c8hp.
7]_UZ)u
privateint[] indexes = newint[0]; Sd2R$r
+*WE<4"!6
privateint startIndex = 0; HWxk>F0
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public PaginationSupport(List items, int 5@" bx=
6d&BN7B
totalCount){ y,tA~
setPageSize(PAGESIZE); H'-Fv!l?
setTotalCount(totalCount); 7 6~x|6)
setItems(items); "!i7U2M'
setStartIndex(0); :c"J$wT/
} nchhNU
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public PaginationSupport(List items, int YES!?^}
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totalCount, int startIndex){ K 2$mz
setPageSize(PAGESIZE); @I2m4Q{O
setTotalCount(totalCount); LyhLPU0^q
setItems(items); -@b&qi7&S
setStartIndex(startIndex); %;(+s7
} W@GcE;#-
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public PaginationSupport(List items, int ^2[0cne
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totalCount, int pageSize, int startIndex){ 6*Qn9Q%p-
setPageSize(pageSize); 1 b+B
setTotalCount(totalCount); HNxJ`x~Z~
setItems(items); "ZEJL.Wy
setStartIndex(startIndex); 0I* ^VGZ
} Z`v6DfK}
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publicList getItems(){ &ME[H
return items; %4Ylq|d
} @Ytsb!!
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publicvoid setItems(List items){ oJVpNE[3]
this.items = items; d}3<nz,
} I&3L1rl3{*
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publicint getPageSize(){ PQ. xmg2
return pageSize; "?Wwcd\
} J\b,rOI f
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publicvoid setPageSize(int pageSize){ yc8FEn!)&
this.pageSize = pageSize; 1 h|cr_
} 2w)0>Y(_
}P#%aE&-
publicint getTotalCount(){ X0^gj>GI|
return totalCount; T9jp*
} s$YKdtR
3}= .7qm
publicvoid setTotalCount(int totalCount){ w~afQA>
if(totalCount > 0){ k{Vc5F
this.totalCount = totalCount; `0uKJFg
int count = totalCount / z{bMW^F
]|<PV5SY3.
pageSize; V:9| 9$G
if(totalCount % pageSize > 0) J4 .C"v0a
count++; [Tby+pC
indexes = newint[count]; @=h%;"
for(int i = 0; i < count; i++){ - y{*U1[
indexes = pageSize * >~_y\
9G` 2t~%
i; h']RP
} YN_#x
}else{ RQWVjF#
this.totalCount = 0; t }7hD
} PwQW5,,h0
} ,w,>pO'[
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publicint[] getIndexes(){ I:U /%cr,
return indexes; xcnHj1r-o'
} (l{+T#
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publicvoid setIndexes(int[] indexes){ $"0t 1
this.indexes = indexes; Q~G+YjM3
} Gg|'T}0X
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publicint getStartIndex(){ Z2)f$ c
return startIndex; Q2cF++Q1
} B)O=wx
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publicvoid setStartIndex(int startIndex){ l
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if(totalCount <= 0) iC?s`c0B
this.startIndex = 0; P0~3<h?U8
elseif(startIndex >= totalCount) <Q/^[
this.startIndex = indexes yA?>v'K
5#g<L ~
[indexes.length - 1]; fO[X<|9
elseif(startIndex < 0) `J[(Dx'y=t
this.startIndex = 0; G]E$U]=9r:
else{ .{`+bT^b<2
this.startIndex = indexes qF`;xa%,}
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[startIndex / pageSize]; Ziuf<X{
} nQdNXv<(
} k(C?6Gfj
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publicint getNextIndex(){ T~cq= i|O
int nextIndex = getStartIndex() + $^
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pageSize; <*0MD6$5
if(nextIndex >= totalCount) :^0g}8$<
return getStartIndex(); Re5m
else \ 3n{%\_
return nextIndex; &
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} IJ!]1fXy+
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publicint getPreviousIndex(){ 33J}AK^FE
int previousIndex = getStartIndex() - 9-o{[
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pageSize; uYIw ?fXy
if(previousIndex < 0) yiQke
return0; v\rOs+.s
else uEWW Y t
return previousIndex; +cvz
} GsqR8n=
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} Z{+h~?63
Y:&1;`FBZ
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抽象业务类 4U<'3~RN
java代码: }U7>_b2
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/** Fly@"W4a
* Created on 2005-7-12 '&Q_5\Tn
*/ g,Kb9['
package com.javaeye.common.business; ZB:Fjq
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import java.io.Serializable; |(}uagfrd
import java.util.List; *0{MAm
po*s
import org.hibernate.Criteria; $}TqBBe
import org.hibernate.HibernateException; UYW%%5p?
import org.hibernate.Session; v!t*Ng
import org.hibernate.criterion.DetachedCriteria; |o~FKy1'z\
import org.hibernate.criterion.Projections; Vyj>&"28
import $^I uE0.
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org.springframework.orm.hibernate3.HibernateCallback; <E$P
import +6*oO|
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org.springframework.orm.hibernate3.support.HibernateDaoS 6ecr]=Cv
KZ ?<&x
upport; 6Kh:m-E9
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import com.javaeye.common.util.PaginationSupport; tH5f;mY,
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public abstract class AbstractManager extends $LAaG65V
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HibernateDaoSupport { T=VVK6Lc:
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privateboolean cacheQueries = false; vMzR3@4e
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*%
privateString queryCacheRegion; YM3oqS D
}n6BI}n
publicvoid setCacheQueries(boolean dmP*2
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cacheQueries){ P{(m: `N
this.cacheQueries = cacheQueries; 9Lk.\.
} EM vV
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publicvoid setQueryCacheRegion(String uWx/V+w
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queryCacheRegion){ aC]~
this.queryCacheRegion = ?P<&8eY
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queryCacheRegion; GK95=?f~8;
} &BG^:4b
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publicvoid save(finalObject entity){ O~{Zs\u9
getHibernateTemplate().save(entity); 4E4o=Z|K
} >m}.}g8
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publicvoid persist(finalObject entity){ :b=`sUn<X+
getHibernateTemplate().save(entity); s7FqE>#c0
} n+zXt?{u
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publicvoid update(finalObject entity){ +/\.%S/
getHibernateTemplate().update(entity); =!U{vT
} V QPq+78
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publicvoid delete(finalObject entity){ ~Ufcy{x#
getHibernateTemplate().delete(entity); &_" 3~:N8k
} \5s!lv*&
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publicObject load(finalClass entity, T]Tz<w W(
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finalSerializable id){ LrF'Hd=O
return getHibernateTemplate().load ?e3q0Lg3|
L}>9@?;GW
(entity, id); m\1*/6oV
} p*Q"<@n
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publicObject get(finalClass entity, zG [-n.
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finalSerializable id){ vm8QKPy
return getHibernateTemplate().get 9!2KpuWji
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(entity, id); q n =6>wP
} =C`v+NPM)|
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publicList findAll(finalClass entity){ F{l,Tl"Jw
return getHibernateTemplate().find("from LYWQqxB
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" + entity.getName()); ik&loM_
} G92=b*x/
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publicList findByNamedQuery(finalString Hd;>k$B
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namedQuery){ <LBMth
return getHibernateTemplate 50_%Tl[
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().findByNamedQuery(namedQuery); rB=1*.}FLc
} T+sO(;
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publicList findByNamedQuery(finalString query, '7Te{^<FQ$
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finalObject parameter){ x!I7vs~~zW
return getHibernateTemplate %eD&2$q*
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().findByNamedQuery(query, parameter); )K5~r>n&
} 3*8#cSQ/6o
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publicList findByNamedQuery(finalString query, "}PmAr e
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finalObject[] parameters){ _ZR2?y-M
return getHibernateTemplate Q|pz].0
=q6yb@
().findByNamedQuery(query, parameters); !_x-aro3<
} -Ep-v4}
+ FLzK(
publicList find(finalString query){ 2H]&3kM3X
return getHibernateTemplate().find A`OU}'v?L
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(query); *RuUf
} C
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publicList find(finalString query, finalObject n'M}6XUw
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parameter){ bZtjg
return getHibernateTemplate().find gVZ~OcB!W
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(query, parameter); z`
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} t%8*$"~X
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public PaginationSupport findPageByCriteria DoImWNLo
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(final DetachedCriteria detachedCriteria){ noL<pkks~R
return findPageByCriteria r--"JO%2
@$~%C) %u
(detachedCriteria, PaginationSupport.PAGESIZE, 0); F;MFw2G
} t,=khZ
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public PaginationSupport findPageByCriteria nq_sbli
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(final DetachedCriteria detachedCriteria, finalint t@!oc"z}@
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startIndex){ ]2Lwd@
return findPageByCriteria .;$/nz6vk
j_ :4_zdBy
(detachedCriteria, PaginationSupport.PAGESIZE, Iy`Zh@"~
3 YRhqp"E
startIndex); gv<9XYByt
} 4}?Yp e-
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public PaginationSupport findPageByCriteria NFc<%#H
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(final DetachedCriteria detachedCriteria, finalint 9Y-s],2V
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pageSize, vw+
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finalint startIndex){ nc l-VN
return(PaginationSupport) FtY*I&
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getHibernateTemplate().execute(new HibernateCallback(){ _=,[5"
publicObject doInHibernate 4Jo:^JV
?b2%\p`"
(Session session)throws HibernateException { 9~>;sjJk
Criteria criteria = S
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detachedCriteria.getExecutableCriteria(session); L!/USh:IP
int totalCount = qW7S<ouh
@gs
Kb*,
((Integer) criteria.setProjection(Projections.rowCount sFB; /*C
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()).uniqueResult()).intValue(); \.Q"fd?a_D
criteria.setProjection a"hlPJlG
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(null); &a-:ZA@
List items = 6)DYQ^4y
c< \:lhl
criteria.setFirstResult(startIndex).setMaxResults I_eYTy-a`1
b/ur!2yr
(pageSize).list(); Ku&0bXP
PaginationSupport ps = 6C) G
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new PaginationSupport(items, totalCount, pageSize, 5H?`a7q N
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startIndex); gxL5%:@
return ps; HiVF<tN
} HtS:'~DYo
}, true); 1LcQ*d
} g^8bY=*
.
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public List findAllByCriteria(final wCc:HfmjJ
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DetachedCriteria detachedCriteria){ *crpM3fO>
return(List) getHibernateTemplate 30[?XVI&
H
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().execute(new HibernateCallback(){
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publicObject doInHibernate aoMQ_@0
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(Session session)throws HibernateException { v,1.n{!;
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); oREZ^pE@
return criteria.list(); nG{jx_{`
} J&Le*R'
}, true); Bz!ddAvlK
} 'du:Bxl`d4
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public int getCountByCriteria(final f{5)yZ`J*
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DetachedCriteria detachedCriteria){ i>0I '~V
Integer count = (Integer) U3%!#E{
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getHibernateTemplate().execute(new HibernateCallback(){ j}S
publicObject doInHibernate I@ }:} 8t
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(Session session)throws HibernateException { z26zl[.
Criteria criteria = B 2&fvv?
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detachedCriteria.getExecutableCriteria(session); S 8h/AW6l
return AUxLch+"5K
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criteria.setProjection(Projections.rowCount u`K+0^)T`
gwR ^Z{
()).uniqueResult(); 7P!/jawxb
} u[PO'6Kzd
}, true); {EZ
;
return count.intValue(); ]@M$.msg@
} -4Y}Y59\
} wdoA>a?q
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用户在web层构造查询条件detachedCriteria,和可选的 NfS0yQPx
'_@=9 \<
startIndex,调用业务bean的相应findByCriteria方法,返回一个 5K{(V^88F
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PaginationSupport的实例ps。 @T]gwJ
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ps.getItems()得到已分页好的结果集 o<@2zhuhrx
ps.getIndexes()得到分页索引的数组 ;z)$wH0xc
ps.getTotalCount()得到总结果数 x\;`x$3t
ps.getStartIndex()当前分页索引 LDr!d1A
ps.getNextIndex()下一页索引 RiaO`|1
ps.getPreviousIndex()上一页索引 ^/mQo`[G
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Wky~ hm
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 #=Q/<r.~G
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一下代码重构了。 H>;km$b +
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我把原本我的做法也提供出来供大家讨论吧: BAg*zYV7
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首先,为了实现分页查询,我封装了一个Page类: _N9yC\
java代码: E)H8jBm6w
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/*Created on 2005-4-14*/ !z58,hv
package org.flyware.util.page; !0 *=z~
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/** u|BD%5+J
* @author Joa aSXoYG0\
* w*#TS8
\
*/ A{mbL2AxwC
publicclass Page { R b\=\
f+%J=Am
/** imply if the page has previous page */ ^7F!>!9Ca
privateboolean hasPrePage; fcD$km
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/** imply if the page has next page */ f![x7D$
privateboolean hasNextPage; f(?>z!n0
z`>a,X
/** the number of every page */ ;oWh Tj`
privateint everyPage; o9q%=/@,
~e,
/** the total page number */ (3{'GX2c
privateint totalPage; 4UC/pGZY
bN<c5
/** the number of current page */ d7$H})[^
privateint currentPage; T*-*U/
@\u)k
/** the begin index of the records by the current %jKR\f G
3,3{wGvHHW
query */ /=,^fCCN
privateint beginIndex; roj/GZAy"
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Nz*qz"T
/** The default constructor */ ;wJLH\/
public Page(){ ;7tOFsV
Rj+}L ~"
} G*\wu&7!
=h5&\4r=
/** construct the page by everyPage 1K09iB
* @param everyPage 8T$:^HW
* */ gC<\1AIu
public Page(int everyPage){ C[n,j#Mvje
this.everyPage = everyPage; }1z=
C<
} <)?H98S
7{8!IcR #
/** The whole constructor */ eem.lVVD
public Page(boolean hasPrePage, boolean hasNextPage, @bfaAh~
tvf"w`H
x #BUIi
int everyPage, int totalPage, N!9DZEcm
int currentPage, int beginIndex){ ^dYFFKQ
this.hasPrePage = hasPrePage; ZJ=-cE2n
this.hasNextPage = hasNextPage; QRgWzaI
this.everyPage = everyPage; C&zgt
:q6}
this.totalPage = totalPage; z})H$]: $
this.currentPage = currentPage; 1g2%f9G
this.beginIndex = beginIndex; 7&'^H8V
} @hQ+pG@s
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/** tojJQ6;J
* @return Z9~~vf#
* Returns the beginIndex. E
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*/ 3`SLMPI
publicint getBeginIndex(){ +qD4`aI
return beginIndex; o
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pt
} H8Pil H
B/i,QBPF]
/** l
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* @param beginIndex RTH dL
* The beginIndex to set. $M$oNOT}Y
*/ T7Lk4cU
publicvoid setBeginIndex(int beginIndex){ 9 n|H%AC
this.beginIndex = beginIndex; xqmJPbA
} %}+j4n
Y\dK-M{$
/** $ hg
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* @return "aB]?4
* Returns the currentPage. yr[iAi"
*/ kx]f`b
publicint getCurrentPage(){ a!Z,~ V8
return currentPage; .6(Bf$E
} ?n? Ep [D
lOI(+74
/** 04WKAP'c
N
* @param currentPage pOlQOdl
* The currentPage to set. fHlmy[V+M
*/ JQQD~J1)E
publicvoid setCurrentPage(int currentPage){ 1 (P>TH
this.currentPage = currentPage; +@usJkxul
} XHlPjw
v|t^th,
/** rZ w&[ G
* @return Ij@YOt
* Returns the everyPage. ~"
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*/ '`/1?,=
publicint getEveryPage(){ dH&N<
return everyPage; ?!Rlp/
} X<,sc;"b`k
.;/@k%>
/** 5W 5\*L
* @param everyPage ^0~?3t5
* The everyPage to set. V8[woJ5x
*/ 7! <cU
publicvoid setEveryPage(int everyPage){ Z-Bw?_e_K
this.everyPage = everyPage; [AE]0cO@
} L7q%u.nB1
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/** jW?.>(
* @return t#6gjfIi
* Returns the hasNextPage. N''9Bt+:
*/ -;Cl0O%
publicboolean getHasNextPage(){ e|"`W`"-
return hasNextPage; Gob1V
} amlE5GK;
rguC#Xt!4
/** #x':qBv#
* @param hasNextPage -.ha\ t0J
* The hasNextPage to set. HQQc<7c",
*/ s-o0N{b?#'
publicvoid setHasNextPage(boolean hasNextPage){ C1r]kF
this.hasNextPage = hasNextPage; v(h
} E"pq ZP =
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/** lwQI
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* @return 5a5I+*
c
* Returns the hasPrePage. 2+sNt6B2
*/ &0Wv+2l@
publicboolean getHasPrePage(){ H.|FEV@
return hasPrePage; H5^'J`0\
} J3S@1"
2@uo2]o)
/** J@p[v3W
* @param hasPrePage /NMd GKr
* The hasPrePage to set. BT`D|<
*/ i7mT<w>?
publicvoid setHasPrePage(boolean hasPrePage){ k3}ymhUf
this.hasPrePage = hasPrePage; JV(|7Sk
} Ol{)U;,`
+ [|2k(U
/** yZUB8erb.
* @return Returns the totalPage. ) i.p[
* &AZr(>
*/ <,HdX,5
publicint getTotalPage(){ Ia0.I " ,
return totalPage; FTtYzKX(bv
} iW.8+?Xq&
#N[nvIi}
/** ZK{VQ~
* @param totalPage ;W'y^jp]"
* The totalPage to set. o*'J8El\y^
*/ l?pZdAE
publicvoid setTotalPage(int totalPage){ ,DXNq`24
this.totalPage = totalPage; &>*fJ
} wu/]M~XwI
%RdCSQ9~
} -9.S?N'T>;
j'X]bd'
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1EyM,$On
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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 4g$mz:vo
h=EJNz>U
个PageUtil,负责对Page对象进行构造: )0yY|E\
java代码: #gUM%$
bF|j%If%
CP]BSyim'
/*Created on 2005-4-14*/ f|1y?w?I
package org.flyware.util.page; `k
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2|qE|3&{'
import org.apache.commons.logging.Log; !3kyPoq+
import org.apache.commons.logging.LogFactory; ^z"90-V^
8ooj)
/** ~+q$TV
* @author Joa }f; Zx)!
* hGcOk[m 4
*/ ^7.864
publicclass PageUtil { Me`jh8(K\6
e7{3:y|]d3
privatestaticfinal Log logger = LogFactory.getLog x5c
pv
%K\_gR}V
(PageUtil.class); V`l.F"<L
[6FCbzS_W
/** 1Ty{k^%
* Use the origin page to create a new page /H: '(W_b;
* @param page Y6?d
y\
* @param totalRecords "F7g8vu
* @return zX"@QB3E
*/ 15)=>=1mR.
publicstatic Page createPage(Page page, int dp&4G6Y<A
_o8il3
totalRecords){ ",B92[}Ar
return createPage(page.getEveryPage(), "o*F$7D!
"c\ZUx_i6
page.getCurrentPage(), totalRecords); QukLsl]U
} ";J1$a
MV-fDqA(
/** %+:%%r=Q
* the basic page utils not including exception Ja4O*C<
LrX7WI
handler 9mEC|(m*WK
* @param everyPage $Dxz21|P7
* @param currentPage +w?RW^:Q=
* @param totalRecords R Q X
* @return page u `1cXL['
*/ )Jz L
publicstatic Page createPage(int everyPage, int f[6;)ZA
5 UpN/\He
currentPage, int totalRecords){ .8<bz4
everyPage = getEveryPage(everyPage); V44IA[
currentPage = getCurrentPage(currentPage); w6F4o;<PR
int beginIndex = getBeginIndex(everyPage, ?dl7!I@<E<
iN %kF'&9
currentPage); ~gNa<tg"1
int totalPage = getTotalPage(everyPage, )V*Z|,#no
s_N?Y)lS+(
totalRecords); 6wYd)MDLL
boolean hasNextPage = hasNextPage(currentPage, lM3UjR|@
n-be8p)-
totalPage); *r6+Vz
boolean hasPrePage = hasPrePage(currentPage); : P>Wd3m
Q mT L-
returnnew Page(hasPrePage, hasNextPage, :rnn`/L
everyPage, totalPage, ryy".'v
currentPage, zF[kb%o
>)YaWcI
beginIndex); *)gbKXb
} p~Fc*g[!
;?"]S/16,
privatestaticint getEveryPage(int everyPage){ ,]gYy00w0s
return everyPage == 0 ? 10 : everyPage; EJ;:O1,6H
} 5`53lK.C
X-|Lg.s
privatestaticint getCurrentPage(int currentPage){ /XEUJC4
return currentPage == 0 ? 1 : currentPage; h$)+$^YI
} R3`!Xj#&M
)@Fuw*
privatestaticint getBeginIndex(int everyPage, int 4eMNKIsvY$
9+)5 #!0
currentPage){ aF7" 4^ P
return(currentPage - 1) * everyPage; l ~kxt2&
} (, Il>cR4
.uG|Vq1v
privatestaticint getTotalPage(int everyPage, int paF$o6\
2 1.;lj
totalRecords){ y#!8S{
int totalPage = 0; L=nyloz,0
LE%3..
!
if(totalRecords % everyPage == 0) 4:GVZR|-
totalPage = totalRecords / everyPage;
M<hX!B
else qn}4PVn4
totalPage = totalRecords / everyPage + 1 ; |_@ '_
#]>Z4=]v
return totalPage; Tp2 `eY5
} '!>LF1W=
2fM*6CaS
privatestaticboolean hasPrePage(int currentPage){ GLrHb3@"N
return currentPage == 1 ? false : true; o(Yj[:+m
} T$RVz
-$WU-7`
privatestaticboolean hasNextPage(int currentPage, 59A@~;.F
-\O%f)R
int totalPage){ bq#*XCt#
return currentPage == totalPage || totalPage == r)UtS4 7
_yw]Cacr\
0 ? false : true; Ea#wtow|-
} [LDsn]{
7t
&KKKV
99j^<)
} T~@$WM(
}wJ-*By{+
't'~p#$,F
D|lp3\`%
>_bH,/D'
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。 $a|C/s+}7>
LxaR1E(Cc'
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 qOAK`{b
Qxr&zT7f
做法如下: #\U;,r
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 wN'Q\l+
?.Z4GWyXa
的信息,和一个结果集List: mxUM&`[
java代码: Khp`KPxz%
.21[3.bp/q
!? !~8J~
/*Created on 2005-6-13*/ w64 /$
package com.adt.bo; YTP6m9hA+
&o@IMbJ8
import java.util.List; :%-xiv
*\ZK(/V
import org.flyware.util.page.Page; xV@/z5Tq
R3=PV{`M
/** 's#"~<L^e
* @author Joa y^pzqv
*/ y
qDE|DIez
publicclass Result {
&!7{2E\7C
Plpt7Pa_
private Page page; #;,dk(URo
:=9?XzCC
private List content; ^UTQcm
7` AQn],
/** }Fy~DsQ
* The default constructor |]FJfMX
*/ pV`?=[h9
public Result(){ MD`1KC_m
super(); uXD?s3Wv
} GR6BpV7
t<~$?tuZ
/** )w\E^
* The constructor using fields x
xMV2&,Jq
* t*X
k'(v
* @param page Xi vzhI4
* @param content 3zi(|B[,?
*/ 1C)
l)pV
public Result(Page page, List content){ cZ>h [XX[
this.page = page; o9&&u1`M/
this.content = content; hes$LH
} ~m4{GzB
^=kUNyY
/** HjG!pO{
* @return Returns the content. l!UF`C0g
*/ \Nd8,hE
publicList getContent(){ ;#c=0*.
return content; OX|nYTp
} L O)&|9xw
<i}lP/U
/** 8bl&-F`
* @return Returns the page. Y [8~M8QX
*/ .C$4jR.KC
public Page getPage(){ |j3fS[.$
return page; k4WUfL d
} L{XNOf3
rO#WG}E<"
/** ="X2AuK%1$
* @param content Z*,Nt6;e
* The content to set. mWhQds6
*/ 'L$%)`;e
public void setContent(List content){ GZt+(q
this.content = content; \jlem <&
} @0js=3!2
19V
/** H\W/;Nn
* @param page 9UF^h{X
* The page to set. %=C49(/K_
*/ e6O +hC]:
publicvoid setPage(Page page){ !yxb=>A
this.page = page; k;aV4
0N9
} ++b1VBP
} +-8S,Rg@
/"$A?}V
?"23X Ke
+
Xc s<+b
VG,O+I'^z
2. 编写业务逻辑接口,并实现它(UserManager, |Dz$OZP
u7L!&/ 6On
UserManagerImpl) >\J({/ #O
java代码: O+ ].'
Pr|:nJs
$_bhZnYp7
/*Created on 2005-7-15*/ /da5"
package com.adt.service; ?f}lYQzM
POZ5W)F(
import net.sf.hibernate.HibernateException; W ='c+3O6
;S,k
U{F
import org.flyware.util.page.Page; {& Pk$Q!
#ZFedK0vv
import com.adt.bo.Result; ]I
pLF#
Y`secUg
/** 3}U {~l!K
* @author Joa ?ks3K-.4
*/ #2&DDy)Bf
publicinterface UserManager { M}jF-z
f8Z[prfP
public Result listUser(Page page)throws +@n8DM{b
P;B<R"
HibernateException; J`uO~W"
sR(or=ub~
} m6'VMW
s"tyCDc.c
12W`7
W Z!?O0.A
k)'y;{IN
java代码: jY: )W*TXt
?%QWpKO7X
g?TPRr~$9
/*Created on 2005-7-15*/ {c(@u6l28
package com.adt.service.impl; xZMQ+OW2i
( o(, ;
import java.util.List; }jfOs(Q]
xOKLc!J
import net.sf.hibernate.HibernateException; ]U4)2s
x6h';W_ 8
import org.flyware.util.page.Page; @pV~Q2%
import org.flyware.util.page.PageUtil;
+n'-%?LD&
%ZKP d8
import com.adt.bo.Result; 6k4ZzQ}
import com.adt.dao.UserDAO; IasWm/
import com.adt.exception.ObjectNotFoundException; q=,
import com.adt.service.UserManager; 5{PT
bjR:5@"
/** lR<1x
* @author Joa 5 R*
*/ ?Q?=I,2bP
publicclass UserManagerImpl implements UserManager { oJ:\8>)9
.!oYIF*0zC
private UserDAO userDAO; Xur{nk~?
gpvzOW/
/** qk+RZ>T<o
* @param userDAO The userDAO to set. ep ,"@,,
*/ EC:u;2f!
publicvoid setUserDAO(UserDAO userDAO){ \dx$G?R
this.userDAO = userDAO; jmE\+yz
} [iO*t,3@h
I:l/U-b7h
/* (non-Javadoc) C6PlO
* @see com.adt.service.UserManager#listUser 5s7C;+
z1AYXW6F
(org.flyware.util.page.Page) Qm(KvL5
*/ G`D~OI
public Result listUser(Page page)throws "sD[P3
(#)-IdXXO<
HibernateException, ObjectNotFoundException { ,E._A(Z
int totalRecords = userDAO.getUserCount(); \>G :mMk/
if(totalRecords == 0) 0#/N ZO
throw new ObjectNotFoundException U!TSAg21P
crDm2oA~t
("userNotExist"); MEI.wJZ
page = PageUtil.createPage(page, totalRecords); ,UveH` n-
List users = userDAO.getUserByPage(page); aAi"
returnnew Result(page, users); U+4W9zhwo
} M^6!{c=MIi
K(:
_52rt
} ~d9@m#_T#~
j,Vir"-)
Fr|Ts>Kx
=>0G
W,D$=Bg
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 #}lq2!f6
!vY5X2?tr,
询,接下来编写UserDAO的代码: `Lr I^9Z
3. UserDAO 和 UserDAOImpl: 4b@Awtk
java代码: O: J;zv\
Cqra\
@p\te7(P%
/*Created on 2005-7-15*/ 5*#3v:l/9
package com.adt.dao; +lNAog
"J=A(w5
import java.util.List; -Uo"!o>x|
Kqn{q4L
import org.flyware.util.page.Page; -qDM(zR
LP{@r ic
import net.sf.hibernate.HibernateException; .S6u{B
/ygC_,mx
/** S [=l/3c
* @author Joa T1_qAz+
*/ ssUm1F\
publicinterface UserDAO extends BaseDAO { a*N<gId
{0IC2jE
publicList getUserByName(String name)throws xE"QX
N
FWb`F&
HibernateException; P.>5`^
},& =r= B
publicint getUserCount()throws HibernateException; B s {n
Be4n\c.
publicList getUserByPage(Page page)throws p+y2w{{
D&]dlY@*
HibernateException; FG{45/0We
F<Y>
} "b6ew2\
RLE6=#4
(RM;T @`
#^zUaPV 7r
0Vwl\,7z9
java代码: hAvX{]
9`|
^cL*6
g+zfa.wQ
/*Created on 2005-7-15*/ AfaoFn+
package com.adt.dao.impl; Z{p62|+Ck@
;#+Se,)
import java.util.List; {[tx^b
>VE!3' /'
import org.flyware.util.page.Page; J12hjzk6@
K."h}f95
import net.sf.hibernate.HibernateException; .CAcG"42
import net.sf.hibernate.Query; QP={b+8
yrCY-'%
import com.adt.dao.UserDAO; wS%j!|xhlV
M?3#XQDvD
/** 7eP3pg#
* @author Joa 7zWr5U.
*/ #-^y9B
public class UserDAOImpl extends BaseDAOHibernateImpl l6y*SW5+
Uoqt
implements UserDAO { wx*)7Y*
d~za%2{
/* (non-Javadoc) Yd>ej1<
* @see com.adt.dao.UserDAO#getUserByName !Bqmw
"<^]d~a_
(java.lang.String) vN8Xq+
*/ okSCM#&:[2
publicList getUserByName(String name)throws a?gziCmS?C
w}:&+B:
HibernateException { <}z,!w8
String querySentence = "FROM user in class ,EuJ0]2
SBog7An9SI
com.adt.po.User WHERE user.name=:name"; z&W5@6")`
Query query = getSession().createQuery o0`|r+E\
k,M%"FLQ
(querySentence); |j>fsk~
query.setParameter("name", name); Xx;4
return query.list(); 'du{ky
}
U%zZw)
oHvVZ
/* (non-Javadoc) $9In\x
* @see com.adt.dao.UserDAO#getUserCount() cpe/GvD5]
*/ %$3)xtS6
publicint getUserCount()throws HibernateException { `GQ'yv
int count = 0; Qf<@
:T*
String querySentence = "SELECT count(*) FROM r-]Hm Y x
A3cW8OClz
user in class com.adt.po.User"; ^cz;UQX~}
Query query = getSession().createQuery gsD0N^
aa10vV
(querySentence); ^N2N>^'&1.
count = ((Integer)query.iterate().next }3xZ`vX[T
%yJ
$R2%*y
()).intValue(); 8Ug`2xS<_
return count; +i1\],7
} _=d
X01
0s+pcqOd^
/* (non-Javadoc) Zyx92z9Y
* @see com.adt.dao.UserDAO#getUserByPage _WeN\F~^
Rb=8(#
(org.flyware.util.page.Page) hq[RU&\
*/ cN]]J
publicList getUserByPage(Page page)throws \8HLQly|@
;xMieqz
HibernateException { SWZA`JVK
String querySentence = "FROM user in class -0R;C` (!
yccF#zU
com.adt.po.User"; \Tii
S
Query query = getSession().createQuery 4Bc<
B6hd*f
(querySentence); 8/16<yZ
query.setFirstResult(page.getBeginIndex()) &:MfLDJ
.setMaxResults(page.getEveryPage()); $4Ko
return query.list(); I'$}n$UvZ
} ZUiInO
X&+*?Q^
} `*to(
)
<xpHlLc
xO nW~Z
( /):
``j8T[g
至此,一个完整的分页程序完成。前台的只需要调用 Y\pRk6,
z')zVoW,
userManager.listUser(page)即可得到一个Page对象和结果集对象 /H m),9NN
^>H+#@R
的综合体,而传入的参数page对象则可以由前台传入,如果用 xM6v0U a
#{]Yw}m
webwork,甚至可以直接在配置文件中指定。 UvPD/qu$8D
3Q-[)Z )
下面给出一个webwork调用示例: 28rC>*+z
java代码: |DZ3=eWZ
w6w'Jx
FA#?+kd
/*Created on 2005-6-17*/ ! !9l@
package com.adt.action.user; V`;$Ua;y
MlBw=Nr
import java.util.List; 'dFhZ08u}
wWU5]v
import org.apache.commons.logging.Log; 5f'<0D;K
import org.apache.commons.logging.LogFactory; C1YG=!
import org.flyware.util.page.Page; xU5+"t~
*[MK{m
import com.adt.bo.Result; _o-lNt+
import com.adt.service.UserService; :a#pzEK
import com.opensymphony.xwork.Action; u|'}a3
*w[\(d'T
/** i8Y$cac!
* @author Joa ^& R
H]q
*/ "BAH=ul5E
publicclass ListUser implementsAction{ V7qc9Gd@I
3-T}8VsiP
privatestaticfinal Log logger = LogFactory.getLog nR()ei^X
[=xJh?*P
(ListUser.class); on=I*?+R
01P ~K|s
private UserService userService; :?}U Z#
M zbs#v0
private Page page; &D[pX|!
h)746T )
privateList users; P4~=_Hh
ggR--`D[
/* .{@aQwN
* (non-Javadoc) xWa96U[
* Qn*a#]p
* @see com.opensymphony.xwork.Action#execute() p@se
5~
*/ ra'h\m
publicString execute()throwsException{ d*A(L5;@
Result result = userService.listUser(page); uv,_?x\'
page = result.getPage(); mm5y'=#
users = result.getContent(); 3nJd0E
return SUCCESS; k'd(H5A
} J^G#x}y
+-B`Fya
/** nvdo|5
* @return Returns the page. eyiGe1^C
*/ YsHZFF
public Page getPage(){ `S{Blv
return page; R1%2]?
} {MaFv
l6C^,xU~IX
/** Du3nK"-g
* @return Returns the users. qPc"A!-i
*/ ]-D;t~
publicList getUsers(){ 1;4]
HNI
return users; #''q :^EQ
} rU{E}
MwlhL?
/** x\
pC&
* @param page &!kr&g#]
* The page to set. =eXJZPR
*/ ( _{\tgSm
publicvoid setPage(Page page){ mu(EmAoenQ
this.page = page; 2eOde(K+
} Pc*+QtQ
bLfbzkNV\1
/** Z{|U!tn
* @param users XU}|Ud562
* The users to set. UBUZ}ZIbN
*/ pzMli^
publicvoid setUsers(List users){ .Fy f4^0
this.users = users; qQ_o>+3VAy
} ?d -$lI
dtdz!'q)Y
/** |^ao,3h#
* @param userService .i7bI2^
* The userService to set. ^r7-|
*/ J:YFy-[w(
publicvoid setUserService(UserService userService){ \y-Lt!}
this.userService = userService; |Ki\Q3O1
} IkU:D"n7
} I#]$H#}Av
l1RpG"
r`Qzn" H
`z=I}6){
Ng6(2Wt0e
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, \?bp^BrI
(]Z$mv!
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 [S}o[v\
r2EIhaGF;
么只需要: E! i:h62
java代码: !zw)! rV=
I\6u(;@
OOEmXb]8
<?xml version="1.0"?> WCbv5)uTUs
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork !KUV,>L
Di3<fp#w#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4No!`O-!&
);^]
is~
1.0.dtd"> GHMoT
"G8w}n:y
<xwork> 8q6b3q:c
tNskB`541
<package name="user" extends="webwork- ?U:LAub
V01-n{~G
interceptors"> K#=)]qIk
HS|X//]
<!-- The default interceptor stack name N{]|!#
4JTFdbx
--> D3LW49
<default-interceptor-ref 4MVa[0Y
<uugT9By
name="myDefaultWebStack"/> QY,.|
JNzNK.E!m-
<action name="listUser" 2EubMG
3
;F=EMz{
class="com.adt.action.user.ListUser"> sLV bFN`
<param EHT5Gf
ndkV(#wQS
name="page.everyPage">10</param> PNSZ
j#
<result -ISI!EU$
bF88F_
name="success">/user/user_list.jsp</result> $I L7c]Gw
</action> MorR&K
9w
-t9X>X
</package> :@TfhQV_=Q
x}G["ZU}v]
</xwork> zMT0ToG
1;p'2-x
0u4:=Z}W
Z2Bl$ \
;as4EqiK
m8Q6ESg<*u
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 djeax
c~0YIk>]
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。 :^DuB_
&v+8RY^F=
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 eu(1bAfS&T
mbBd3y
%3 ecV$
Aw)='&;^z
R$@|t?
我写的一个用于分页的类,用了泛型了,hoho X[:&p|g]
$cri"G
java代码: %C%~f{4
T`{W$4XS
r'/7kF- 5
package com.intokr.util; b$P=rIB
8>Hnv]p
import java.util.List; d ,| W
L$7
NT}L
/** mnM#NT5]
* 用于分页的类<br> 8t!/Op?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> dA[Z\
* CUB= T]
* @version 0.01 M3j_sd'N
* @author cheng >3
Q%Yn
*/ !Y3w]_x[:
public class Paginator<E> { H4 }^6><V
privateint count = 0; // 总记录数 Ij
hC@5qk
privateint p = 1; // 页编号 DCv~^
privateint num = 20; // 每页的记录数 3&kHAXzM
privateList<E> results = null; // 结果 y; Up@.IG
QDS=M]
/** *5iNw_&
* 结果总数 B98&JoS
*/ g]9!Pi8jn
publicint getCount(){ d#.9!m~.
return count;
Vkdchc
} ~xqRCf{8
le?hCPHkp
publicvoid setCount(int count){ xI}h{AF7
this.count = count; k#TonT
} S,LW/:,
,~t{Q*#_h
/** fr8:L!9
* 本结果所在的页码,从1开始 ( Kh<qAP_n
* 4"fiEt,t<x
* @return Returns the pageNo. D}l^ow
*/ 89:Y s=
publicint getP(){ f5+a6s9
return p; NaC^q*>9
} hf
rF7{yj
}3cOZd_,t
/** `#hdb=3
* if(p<=0) p=1 yw`xK2(C$
* |HXI4MU"
* @param p X62h7?'Pd
*/ 'u$e2^
publicvoid setP(int p){ 8moX"w\~_h
if(p <= 0) [)|P-x-<
p = 1; |a#4
this.p = p; QT /TZ:
} ++-\^'&1
0n+Wv@/
/**
M@S6V7
* 每页记录数量 CF3Z`xD
*/ }wrZP}zM>
publicint getNum(){ ,{A-<=6t
return num; ;JMd(\+-
} j"*ZS'0
mXT{)pU
/** G<,@|6"w
* if(num<1) num=1 f_X]2in
*/ '/kSUvd
publicvoid setNum(int num){ >(Jy=m?
if(num < 1) oop''6`C%
num = 1; IC>OxYg*
this.num = num; k.>*!l0
} `6`NuZ*6g
~?8B~l^
/** dhpEBJ
* 获得总页数 SlI0p&2,
*/ a9qB8/Gg[
publicint getPageNum(){ "BZ6G`
return(count - 1) / num + 1; RG-pN()
} $QmP'
<
]Qe;+p9vU
/** B\1F
* 获得本页的开始编号,为 (p-1)*num+1 _H(m4~M
*/ orCD?vlh
publicint getStart(){ l@nkR&4[
return(p - 1) * num + 1; Ok[y3S
} rIp84}
ET1/oG<@
/** I&qT3/SVI
* @return Returns the results. 8SK}#44Xz
*/ 0\O*\w?
publicList<E> getResults(){ 6*Jd8Bva\o
return results; >l{<p(
} h|"98PI
#>dfP"}&,
public void setResults(List<E> results){ ]kx)/n-K
this.results = results; jftoqK-
p
} l~Je]Qt
FqAW><
public String toString(){ d9h"Q
StringBuilder buff = new StringBuilder -8; ,#
1tU}}l
(); *_}|EuY
buff.append("{"); #~%tdmGuL
buff.append("count:").append(count); 4(Gs$QkSo|
buff.append(",p:").append(p); " &'Jw
buff.append(",nump:").append(num); 'F^nW_ryW
buff.append(",results:").append C72?vAc,F
gP1~N^hke]
(results); pzmm cjEC
buff.append("}"); \^vf`-uG
return buff.toString(); pUki!TA
} JS% &ipm
/Za'L#=R
} B)J.(k`p
|ZW%+AQ|
/`#sp