Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,^\2P$rT
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .oeX"6K
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 kZmpu?P
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 (2$p{Uf
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分页支持类: vVFy*#I#_[
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java代码: h eV=)8
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package com.javaeye.common.util; ?fi,ifp*|l
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import java.util.List; ?iWi
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publicclass PaginationSupport { P*3BB>FO
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publicfinalstaticint PAGESIZE = 30; |}Nn!Sj>#;
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privateint pageSize = PAGESIZE; 0tT(W^ho g
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privateList items; Dv5D~on{
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privateint totalCount; gc-@"wI?
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privateint[] indexes = newint[0]; Lh!J >
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privateint startIndex = 0; CVL3VT1j0
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public PaginationSupport(List items, int "&G/T ?4
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totalCount){ 1W^taJH]
setPageSize(PAGESIZE); Krqtf
setTotalCount(totalCount); ^:^9l1]
setItems(items); eg;~zv
setStartIndex(0); Z`ID+
} 5B3G
@KR
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public PaginationSupport(List items, int A$Hfr8w1u
7:plQ!7^
totalCount, int startIndex){ oAODp!_c
setPageSize(PAGESIZE); S2sQOM@
setTotalCount(totalCount); N4F.Y"R$(
setItems(items); 6xTuNE1
setStartIndex(startIndex); &^}1O:8e
} ib#KpEk
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public PaginationSupport(List items, int 96( v
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totalCount, int pageSize, int startIndex){ L*xhGoC=
setPageSize(pageSize); cQy2"vtU
setTotalCount(totalCount); zPn+V7F
setItems(items); "O3tq=Q
setStartIndex(startIndex); ls\WXCH
} =.Pw`.
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publicList getItems(){ tdBm
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return items; n8~N$tDU
} #Z?A2r!1
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publicvoid setItems(List items){ "l3_=Gua
this.items = items; BC&S> #\
} N{9v1`B
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publicint getPageSize(){ Gp?a(-K5
return pageSize; [B\h$IcRv
} o=1Uh,S3R
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publicvoid setPageSize(int pageSize){ 4gI/!,J(b
this.pageSize = pageSize; 4;e5H_}Oo
} p& y<I6a,
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publicint getTotalCount(){ ;DqWh0
return totalCount; !;q&NHco
} _{I3i:f9X8
q9KHmhUD
publicvoid setTotalCount(int totalCount){ fInb[
if(totalCount > 0){ HVR /7&g
this.totalCount = totalCount; ry`Ho8N
int count = totalCount / AifWf2$S
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pageSize; 5d Eh7XL
if(totalCount % pageSize > 0) SYAyk
count++; Pr':51(
indexes = newint[count]; a!6{:8Zi0
for(int i = 0; i < count; i++){ deBY5|
indexes = pageSize * wN_Vfb
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} EH+"~-v)ae
}else{ u^@f&BIG]:
this.totalCount = 0; }eCw6
} H%qsjB^
} '\l"
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publicint[] getIndexes(){ Qp)v?k ]
return indexes; Vz~{UHH6
} @Q)OGjaq
@'#,D!U
publicvoid setIndexes(int[] indexes){ kyR:[+je
this.indexes = indexes; uw>Ba %5
} g1/:Q%R,
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publicint getStartIndex(){ jwc)Lj}
return startIndex; k^3>Y%^1
} [A+
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publicvoid setStartIndex(int startIndex){ n,vct<&z@
if(totalCount <= 0) xK *b1CB
this.startIndex = 0; $p1(He0 2
elseif(startIndex >= totalCount) I5k$H$
this.startIndex = indexes ^cOUQ33
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[indexes.length - 1]; B]nEkO'a:
elseif(startIndex < 0) CKYc\<zR0l
this.startIndex = 0; N]>=p.#j
else{ I&D5;8
this.startIndex = indexes ,?J!
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[startIndex / pageSize]; Sj%u)#Ub
} >{q]&}^U
} C)um9}
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publicint getNextIndex(){ 5V?&8GTe
int nextIndex = getStartIndex() + {%rA1g
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pageSize; B~1_ 28\
if(nextIndex >= totalCount) H4WP~(__
return getStartIndex(); >8~.wXyoC
else !a{^=#qq&I
return nextIndex; z Xg3[orF
} xT3BHnQ(
pj\u9
L_
publicint getPreviousIndex(){ du<tGsy
int previousIndex = getStartIndex() - [g7L&`f9
g;H=6JeG/
pageSize; ^h(ew1:
if(previousIndex < 0) t|w_i-&b,
return0; k0OYJ/
else Y+kfBvxyf
return previousIndex; r<9Iof4
} j@n)kPo,1
k$ 4y9{
} f}o\*|k_|
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抽象业务类 \T4v|Pw\
java代码: y_*
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/** H9'$C/w
* Created on 2005-7-12 &W|[r(
*/ iN bIp"W
package com.javaeye.common.business; }5ret
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import java.io.Serializable; D>`xzt '.6
import java.util.List; iowTLq!?
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import org.hibernate.Criteria; C'>|J9~Gz
import org.hibernate.HibernateException; ;;!yC
import org.hibernate.Session; NxkGOAOE
import org.hibernate.criterion.DetachedCriteria; ..IfP@
import org.hibernate.criterion.Projections; VpE*(i$
import X:A^<L
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org.springframework.orm.hibernate3.HibernateCallback; 4V{:uuI;f
import []\+k31D
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org.springframework.orm.hibernate3.support.HibernateDaoS ]Z>}6!
;@mS^ik")$
upport; 6/f7<
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import com.javaeye.common.util.PaginationSupport; 35h8O,Y
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public abstract class AbstractManager extends fW{(lPx
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HibernateDaoSupport { S(k3 `;K
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privateboolean cacheQueries = false; OC_+("N
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privateString queryCacheRegion; piJu+tUy
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publicvoid setCacheQueries(boolean F|IAiE
@D]5c ivm_
cacheQueries){ +cJL7=V&
this.cacheQueries = cacheQueries; 8+~
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} E~DQ-z
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publicvoid setQueryCacheRegion(String h\$$JeSV]
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queryCacheRegion){ `68@+|#
this.queryCacheRegion = .u)X3..J
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queryCacheRegion; x!?u^
} 3$jT*OyG#
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publicvoid save(finalObject entity){ Ab~3{Q]#
getHibernateTemplate().save(entity); qFicBpB
} B~'vCuE
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publicvoid persist(finalObject entity){ P9/q|>F
getHibernateTemplate().save(entity); "SNn^p59k
} |.(dq^
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publicvoid update(finalObject entity){ [T|aw1SoN
getHibernateTemplate().update(entity); t=BUN
} rF3wx.
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publicvoid delete(finalObject entity){ Bj+S"yS
getHibernateTemplate().delete(entity); #QS`_TlKk
} Q1T$k$n
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publicObject load(finalClass entity, WEw6He;
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finalSerializable id){ =%BSKSG.
return getHibernateTemplate().load C1V|0hu
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(entity, id); fnpYT:%fG
} Y@NNrGDkT*
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publicObject get(finalClass entity, 5^}\4.eXo
9)D6Nm
finalSerializable id){ SU MrFd~
return getHibernateTemplate().get o5u3Fjz3
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(entity, id); 4`lLf
} [xbSYu,&
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publicList findAll(finalClass entity){ $r^GE
return getHibernateTemplate().find("from Fh)IgzFj
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" + entity.getName()); -$t{>gO#Y
} ^gN6/>]qrY
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publicList findByNamedQuery(finalString u^^vB\"^
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namedQuery){ nxO"ua
return getHibernateTemplate ^NLmgwQ
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().findByNamedQuery(namedQuery); n|6Ic,:[
} aR[JD2G
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publicList findByNamedQuery(finalString query, 2\)xpOj
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finalObject parameter){ O24m;oHM
return getHibernateTemplate 99]R$eT8
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().findByNamedQuery(query, parameter); kAKK bmE
} d.[8c=$
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publicList findByNamedQuery(finalString query, b\ X@gq
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finalObject[] parameters){ 9-sw!tKx
return getHibernateTemplate gx-2v|pZ
AL[KpY
().findByNamedQuery(query, parameters); DMs,y{v
} b
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publicList find(finalString query){
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return getHibernateTemplate().find #9=Vg
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(query); :vYYfs&
} E}%B;"b/Tj
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publicList find(finalString query, finalObject N'F77
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parameter){ %3s1z<;R[S
return getHibernateTemplate().find *}Xf!"I#]N
#^#PPO
(query, parameter); [m->5H
} 36.Z0Z1'F>
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public PaginationSupport findPageByCriteria 'Oxy$U
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(final DetachedCriteria detachedCriteria){ q~rEq%tk
return findPageByCriteria QER?i;-wb
H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \h+AXs<j
} *$#W]bO
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public PaginationSupport findPageByCriteria cv8L-Z>x.=
3v(* 5
(final DetachedCriteria detachedCriteria, finalint 9/9j+5}+
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startIndex){ sXqz+z$*
return findPageByCriteria bkRLC_/d
n*o-Lo+Fe.
(detachedCriteria, PaginationSupport.PAGESIZE, f0!))/rSD
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startIndex);
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} /pm]BC
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public PaginationSupport findPageByCriteria p}jE
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(final DetachedCriteria detachedCriteria, finalint 5CuuG<0
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pageSize, a,Sw4yJ!Q
finalint startIndex){ =NpYFKmMhV
return(PaginationSupport) FW.7'7G@n
z Eq GD2"
getHibernateTemplate().execute(new HibernateCallback(){ 57aXQ8u{
publicObject doInHibernate r=Gks=NX"
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(Session session)throws HibernateException { Y=%tn8<
Criteria criteria = % BVs47g
v/@^Q1G/:
detachedCriteria.getExecutableCriteria(session); 60P<4
int totalCount = "33Fv9C#bK
0Vj4+2?L5;
((Integer) criteria.setProjection(Projections.rowCount 9K.Vb1&
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()).uniqueResult()).intValue(); dA#Q}.*r
criteria.setProjection Q_1:tW
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(null); ``V"
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List items = WJ$bf(X*
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criteria.setFirstResult(startIndex).setMaxResults Ha(c'\T(\
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(pageSize).list(); 09|K>UC)v
PaginationSupport ps = imo$-}A
#TeG-sFJg@
new PaginationSupport(items, totalCount, pageSize, ]"r&]qx7
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startIndex); @_-hk|Nl@
return ps; )5rb&M}
} Ut*`:]la
}, true); 6O|@xvg
} vhe>)h*B
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public List findAllByCriteria(final w+C7BPV&
t\?ik6
DetachedCriteria detachedCriteria){ mGtdO/C#B
return(List) getHibernateTemplate FFl!\y*0z
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().execute(new HibernateCallback(){ \}+_Fo/
publicObject doInHibernate EtJHR
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(Session session)throws HibernateException { G"klu
Criteria criteria = grS:j+_M2m
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detachedCriteria.getExecutableCriteria(session); I+BHstF5um
return criteria.list(); Bu#E9hJFvA
} U GD2
}, true); %u? >#
} <S\jpB
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public int getCountByCriteria(final "
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DetachedCriteria detachedCriteria){ ,f<?;z
Integer count = (Integer) vmi+_]
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getHibernateTemplate().execute(new HibernateCallback(){ ]}*R| 1
publicObject doInHibernate IW>T}@
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(Session session)throws HibernateException { 7zA'ri3w
Criteria criteria = 8R2QZXJb-
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detachedCriteria.getExecutableCriteria(session); cU
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return 0bz'&
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criteria.setProjection(Projections.rowCount .Fs7z7?Y
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()).uniqueResult(); 0f~C#/[t7
} ,C
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}, true); Ed"h16j?z
return count.intValue(); e63uLWDT
} 4h~iPn'Wl
} +$u$<z3Q
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用户在web层构造查询条件detachedCriteria,和可选的 C+'/>=>a.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %Da8{%{`Pc
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PaginationSupport的实例ps。 vBRQp&YwX
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ps.getItems()得到已分页好的结果集 !i{aMxUP
ps.getIndexes()得到分页索引的数组 Z LB4m`
ps.getTotalCount()得到总结果数 OPwtV9%
ps.getStartIndex()当前分页索引 4S5,w(6N
ps.getNextIndex()下一页索引 j\,EO+ZQCv
ps.getPreviousIndex()上一页索引 L\Aq6q@c
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r) HHwh{9
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Q7*SE%H
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一下代码重构了。 kv3E4,<9
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我把原本我的做法也提供出来供大家讨论吧: sA/pVU
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首先,为了实现分页查询,我封装了一个Page类: +Fuqchjq
java代码: 1|RANy
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/*Created on 2005-4-14*/ >XK
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package org.flyware.util.page; d^RxQuA
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/** /~}}"zx&
* @author Joa `Zf^E
>)
* 1HXjN~XF
*/ DAS/43\
publicclass Page { J]v%q,"
aIJt0;
/** imply if the page has previous page */ ~5_Ad\n9
privateboolean hasPrePage; u6T+Cg
18~>ZR
/** imply if the page has next page */ QOjqQfmM;
privateboolean hasNextPage; qLw{?sH}J/
{ D^{[I
/** the number of every page */ _]yn"p
privateint everyPage; Id'X*U7Q
8JM&(Q%#
/** the total page number */ 5i>$]*o
privateint totalPage; b@rVo;
9
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/** the number of current page */ -}=i 04^
privateint currentPage; Rec6c&5_
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/** the begin index of the records by the current 1KMLG=
y<HO:kZ8`
query */ >_e]C}QUr
privateint beginIndex; >*]Hq.&8
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/** The default constructor */ ?!9)q.bW
public Page(){ yOphx07 (
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} }lh I\q
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/** construct the page by everyPage PK;*u,V
* @param everyPage =+ytTQc*ot
* */ f47Od-\-
public Page(int everyPage){ N"8_S0=pw
this.everyPage = everyPage; #.it]Nv{
} 2Or'c`|
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/** The whole constructor */ l;JA8o\x
public Page(boolean hasPrePage, boolean hasNextPage, (^@ra$.
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int everyPage, int totalPage, #cnq(S=.
int currentPage, int beginIndex){ L[^9E'L$
this.hasPrePage = hasPrePage; {p;zuCF1
this.hasNextPage = hasNextPage; ~;1l9^N|
this.everyPage = everyPage; ~KW,kyXBnD
this.totalPage = totalPage; Qj,]N@7
this.currentPage = currentPage; 7[I}*3Q'
this.beginIndex = beginIndex; 7N-w eX
} :,Pn3xl
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/** N$h{Yvbn
* @return {U!8|(
* Returns the beginIndex. .z
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*/ GqWB{$J;"
publicint getBeginIndex(){ F{EnOr`,m=
return beginIndex; kB/D!1
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} U 'R)x";=
?**+e%$$
/** 6b+b/>G0
* @param beginIndex 7]9
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* The beginIndex to set. ]<H&+ &!
*/ IqC]! H0
publicvoid setBeginIndex(int beginIndex){ V\u>"3BQw
this.beginIndex = beginIndex; Gs9:6
} RT)d ]u
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/** 6xWe=QGE
* @return ANJ$'3tg
* Returns the currentPage. '<rZm=48
*/ zRq-b`<7V
publicint getCurrentPage(){ 30XR
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return currentPage; V>R8GSx
} %1O;fQL
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/** _h X]%
* @param currentPage ;cPy1
* The currentPage to set. >)spqu]
*/ AI,(z;{P
publicvoid setCurrentPage(int currentPage){ Sg6"WV{<
this.currentPage = currentPage; V#cqRE3XNi
} x/;bu W-
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/** Z7_m)@%;kk
* @return JS*m65e
* Returns the everyPage. um4yF*3b9
*/ LXEfPLS
publicint getEveryPage(){ &K/ya7
return everyPage; qjf[zF
} } w
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dZi(&s
/** '[C.|)"
* @param everyPage H2um|6>
* The everyPage to set. F{eU";D
*/ G`\f
publicvoid setEveryPage(int everyPage){ Xb{
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this.everyPage = everyPage; (xVsDAp=@
} L5#P[cHzz
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/** blTo5NLX
* @return 1E73i_L
* Returns the hasNextPage. 9[m6Li
*/ :E>HE,1b+
publicboolean getHasNextPage(){ 8"dv _`ym
return hasNextPage; q~3,yyu
} |4T!&[r
?gJy3@D
/** 6`]$qSTS
* @param hasNextPage A8pIs
* The hasNextPage to set. D9FJ 1~
*/ vgUb{D
publicvoid setHasNextPage(boolean hasNextPage){ zipS
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this.hasNextPage = hasNextPage; =dII- L=`
} )yTm.F
QNARkYY~|
/** iMs5zf<M
* @return hRty [
* Returns the hasPrePage. WHjUR0NZ
*/ WDg+J
publicboolean getHasPrePage(){ $OP7l>KZY
return hasPrePage; Z\HX~*,6
} `FsH}UPu
b
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/** 0&/b42W
* @param hasPrePage ;PjQt=4K
* The hasPrePage to set. &2 `F n!m
*/ sFQ^2PwbS
publicvoid setHasPrePage(boolean hasPrePage){ #|*F1K
this.hasPrePage = hasPrePage; Q($Z%1S
} q-c=nkN3
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/** Y=?yhAw
* @return Returns the totalPage. hi0R.V&
* L+CyQq
*/ TZ2=O<Kj
publicint getTotalPage(){ :'*DPB-
return totalPage; 7vABq(
} ( YQWbOk
*,Za6.=
/** {%IE xPJ
* @param totalPage ,:??P1
* The totalPage to set. w~
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*/ f|R"uW +
publicvoid setTotalPage(int totalPage){ 'A:x/iv}^
this.totalPage = totalPage; %K>.lh@
} [o.B
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} Fd#m<"
cOPB2\,
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}S3qBQTYL
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 Er{#ziN+
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个PageUtil,负责对Page对象进行构造: TpHfS]W-P
java代码: cCa|YW^j
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/*Created on 2005-4-14*/ ?c7*_<W5
package org.flyware.util.page; Ur5FC r
+QE^\a
import org.apache.commons.logging.Log; ^`G`phd$
import org.apache.commons.logging.LogFactory; TEMw8@b
1P(|[W1
/** ,}:G\u*Fu
* @author Joa r\blyWi
* k%E2n:|*
*/ 04*6(L)h*
publicclass PageUtil { WdnIp!
:"l-KQ0
privatestaticfinal Log logger = LogFactory.getLog %zSuK8kxV
fwBRWr9
(PageUtil.class); OX"j#
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/** 'w14sr%
* Use the origin page to create a new page 1*dRK6
* @param page Bf$_XG3
* @param totalRecords #?XQ7Im
* @return '&sE=.
*/ (XXheC
publicstatic Page createPage(Page page, int La@
+>
}sx_Yj
totalRecords){ P(;?kg}0
return createPage(page.getEveryPage(), VwEb7v,^0\
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page.getCurrentPage(), totalRecords); ,9P:Draxs`
} <a[Yk 2
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/** Z*])6=2Q
* the basic page utils not including exception $DZHQH
<ERB.d!
handler uaOKv.%
* @param everyPage on8WQf'A#
* @param currentPage J7v|vjI
* @param totalRecords MSV2ip3
* @return page 0d3+0EN{
*/ gd0Vp Xf'
publicstatic Page createPage(int everyPage, int |,aG%MTL
1]}#)-
currentPage, int totalRecords){ Z(9u<
everyPage = getEveryPage(everyPage); 8HZs>l
currentPage = getCurrentPage(currentPage); YFTjPBV
int beginIndex = getBeginIndex(everyPage, ;r6jx"i
f}L*uw
currentPage); Vp<seO;7o
int totalPage = getTotalPage(everyPage, JICawj:I
VL[kJi
totalRecords); >/#KI~}'N
boolean hasNextPage = hasNextPage(currentPage, _ib"b#
_$p$")
totalPage); 3 ( ]M{4j
boolean hasPrePage = hasPrePage(currentPage); N |1>ooU[
OKHX)"j\\
returnnew Page(hasPrePage, hasNextPage, n=,\;3Y=
everyPage, totalPage, !sRngXCXk?
currentPage, >+mD$:L
)NO<s0?&
beginIndex); 8&Myva
} &bhq`>
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privatestaticint getEveryPage(int everyPage){ 8v71e>
return everyPage == 0 ? 10 : everyPage; .)+hH y
} Z lHDi!T
*-12VIG'H
privatestaticint getCurrentPage(int currentPage){ 4:7V./" 9
return currentPage == 0 ? 1 : currentPage; !bC+TYsU
} :aG#~-Q
5'Q|EIL
privatestaticint getBeginIndex(int everyPage, int af|5n><~A
]7Fs$y.
currentPage){ suH&jE$ x
return(currentPage - 1) * everyPage; Nk[2nyeO>
} :d8W+|1u
cv(PP-'\
privatestaticint getTotalPage(int everyPage, int {,cCEXag%
k/03ZxC-
totalRecords){ )?2e
int totalPage = 0; HK~xOAF
,KJw|x4}\
if(totalRecords % everyPage == 0) @
a4/ELx
totalPage = totalRecords / everyPage; e;GU
T:
else 2..,Sk
totalPage = totalRecords / everyPage + 1 ; ~Xlrvb}LP
x'zBK0i
return totalPage; TM8=U-A
} 7?v#'Ies
nr)c!8
privatestaticboolean hasPrePage(int currentPage){ 63!rUB!
return currentPage == 1 ? false : true; ?+c`]gO7N
} ZvGgmLN
UA~RK2k?
privatestaticboolean hasNextPage(int currentPage, {"vkji>
W-
$a
Y2
int totalPage){ !WkIi^T
return currentPage == totalPage || totalPage == 3@n>*7/E
+m}Pmi$
0 ? false : true; 1G7b%yPA
} < pTTo
s!+"yK
4Iq'/r
} y{9~&r
[0OJdY4
$^ 'aCU0C
lZ&]|*>
@FN*TJ
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 `O^G5 0
=op%8NJf
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 PS
S?|Vk
d/74{.
做法如下: jxgj,h"}9`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 GFk1/ F
zciCcrJ
的信息,和一个结果集List: rC_*sx
r^
java代码: g`k?AM\
a4gi,pz$]
]ALc;lb-}
/*Created on 2005-6-13*/ rs=q!
P"u[
package com.adt.bo; O;HY%
GO! uwo:
import java.util.List; N:VX!w
W
YW|P2*
import org.flyware.util.page.Page; ^")F7`PF
r,(et
/** d {2
* @author Joa mgZf3?,)
*/ 1x~U*vbhQ
publicclass Result { `A/j1UWJ
wzjU,Mwe
private Page page; w>xV
]+DI.%
private List content; V2|3i}V"
4*Z6}"
/** _kFYBd
* The default constructor l_/C65%.:
*/ vQ@2FZzu>
public Result(){ >yJ-4lgZ
super(); 2WvN2"f3
} w'7R4
rAQF9O[
/**
,%#
* The constructor using fields ,}D}oo*
* '[ P}&<ie,
* @param page P
,eH5w"
* @param content mT*{-n_Zs
*/ 1U\$iy8}
public Result(Page page, List content){ G&eP5'B4i
this.page = page; qu6DQ@
~YC
this.content = content; $trAC@3O@
} 9=dkx^q
FZpKFsPx
/** 9O,,m~B
* @return Returns the content. Lb=W;9;
*/ %bb~Y"
publicList getContent(){ ~:sE:9$z
return content; qBk``!|s]
} oCi
~P}r
*HM?YhR
/** ,je`YEC
* @return Returns the page. J#3{S]*v_
*/ L$v^afP?
public Page getPage(){ o5Rz%k#h
return page; ET^ |z
} \[wCp*;1}
mZ0J!QYk
/** pF=g||gS
* @param content H ;@!?I
* The content to set. y@ek=fT%4
*/ m)?5}ZwAH
public void setContent(List content){ 1ywU@].6J]
this.content = content; 0WxCSL$#I
}
r@)A
k
6DSH`-;
/** !#D=w$@r:
* @param page =)<3pG O
* The page to set. P]<= ! F
*/ 9 |:^k.
publicvoid setPage(Page page){ OjnJV
this.page = page; R 4EEelSZu
} t)1phg4H)
} JSMPyj
h%#_~IA:|
4,eQW[;kk
CVKnTEs
E%k7wM {
2. 编写业务逻辑接口,并实现它(UserManager, U
:9=3A2$x
j=sBq.S
UserManagerImpl) )GB`*M[
java代码: 1IA5.@G:
\MYU<6{u
KHj6Tg;)
/*Created on 2005-7-15*/ 6!7Pm>ml
package com.adt.service; +$beo2x6
[F([
import net.sf.hibernate.HibernateException; ^o<[.
)
s^|\9%WD
import org.flyware.util.page.Page; 99ASIC!
w^VSj%XH!
import com.adt.bo.Result; whkJ pK(
L=1~ f-
/** Wpm9`K
* @author Joa 0g(6r-2)7
*/ [Z}B"
publicinterface UserManager { T[Q"}&bB
Gi$gtLtNh
public Result listUser(Page page)throws Q9y*:
wa3F
HibernateException; |+E KF.K
L~0&
Q
} $iJnxqn
,w\ wQn>]K
6Dzs? P
LDX*<(
Jh2Wr!5
java代码: #vnT&FN0[
{OxWcK\2@h
^e9aD9
/*Created on 2005-7-15*/ yz)ESQ~va
package com.adt.service.impl; Ee?;i<u
(:} <xxl
import java.util.List; zHFTCL>"
Wvr+y!F
import net.sf.hibernate.HibernateException; OlcP(
4]BJ0+|mT
import org.flyware.util.page.Page; nP_=GI
import org.flyware.util.page.PageUtil; x0x $ 9
Zc\S$+PM
import com.adt.bo.Result; ,olwwv_8G
import com.adt.dao.UserDAO; @\!!t{y
import com.adt.exception.ObjectNotFoundException; F.KrZ3%4iB
import com.adt.service.UserManager; fPE ?hG<x
^CQ1I0
/** O)5#Fcp(
* @author Joa ]gP8?s|
*/ 'Oy5e@G+?
publicclass UserManagerImpl implements UserManager { rt.[,m
{E~l>Z88
private UserDAO userDAO; syFI$rf
_
ZlM_m
>,o
/** \!PV*%P
* @param userDAO The userDAO to set. (t74a E pi
*/ t,Q'S`eTU
publicvoid setUserDAO(UserDAO userDAO){ A+2oh3
this.userDAO = userDAO; TzY!D*%z
} 6UB6;-
Tf l;7w.(A
/* (non-Javadoc) 7|~:P$M
* @see com.adt.service.UserManager#listUser 3/tJDb5
q!2<=:f
(org.flyware.util.page.Page) ;Uk!jQh
*/ u%aFb*
public Result listUser(Page page)throws E4m:1=Nd~]
.;Z.F7{q
HibernateException, ObjectNotFoundException { 5&%fkZ0
int totalRecords = userDAO.getUserCount(); j];G*-iv{
if(totalRecords == 0) [tN` :}?
throw new ObjectNotFoundException W"O-L
}bgo )<i
("userNotExist"); *. dKR
page = PageUtil.createPage(page, totalRecords); >nNl^ yqW
List users = userDAO.getUserByPage(page); [D9 :A
returnnew Result(page, users); KL~AzLI
} X!7Xg
}z{wQ\
} X8.y4{5
y {;u@o?T
a^/K?lAB8
TMtI^mkB:
s<#N]mp'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ~._ko
D?J#u;h~f
询,接下来编写UserDAO的代码: UGf6i"F
3. UserDAO 和 UserDAOImpl: u7~mnl
java代码: cP('@K=p
M%;"c?g
:5<#X8>d
/*Created on 2005-7-15*/ .J:;_4x
package com.adt.dao; #}j]XWy
Nc"NObe
import java.util.List; H CuK
U_}hfLILi
import org.flyware.util.page.Page; N=<=dp(
w?/f Z x
import net.sf.hibernate.HibernateException; 64b<0;~
ze$Y=<S
/** e9}8RHy1$
* @author Joa F b2p(.
*/ XP4jZCt9
publicinterface UserDAO extends BaseDAO { U>1b9G"_
mR!rn^<l
publicList getUserByName(String name)throws :OX$LCi
>OTl2F}4 !
HibernateException; -Fa98nV.WB
$&Ac5Zo%}
publicint getUserCount()throws HibernateException; +qZc}
7rJF
k)Zn>
publicList getUserByPage(Page page)throws ac3_L$X[
2gH_$
HibernateException; AW62~*
,=x
RoXYB}
} ?}v}U^
lnjL7x
`L;OY 4
5C*?1&
!
y78z>(jV
java代码: IF^[^^v+H
dGa@<hg
%/X2 l
/*Created on 2005-7-15*/ .2/,XwIr
package com.adt.dao.impl; !b'IfDp[-!
^} tLnF
import java.util.List; wyNC|P;j$g
h9U+%=^O
import org.flyware.util.page.Page; H[Cj7{V
3 ^pYCK%
import net.sf.hibernate.HibernateException; =J`gGDhGY-
import net.sf.hibernate.Query; s v6INe:
.dt#2a_5q
import com.adt.dao.UserDAO; vD_u[j]
u9 %;{:]h
/** 3m3
EXz
* @author Joa MHGj vSx
*/ d`UF0T
public class UserDAOImpl extends BaseDAOHibernateImpl *J.c $1#h
e7h\(`J0lj
implements UserDAO { H a90
]u~Os<
/* (non-Javadoc) W.z$a.<(rF
* @see com.adt.dao.UserDAO#getUserByName fHLFeSfH
aQxe)
(java.lang.String) A}gYcc85Z
*/ 3V"dG1?
publicList getUserByName(String name)throws q$3HvZP
kGruo5A
HibernateException { h<GyplG
String querySentence = "FROM user in class nhp)yW
x
Ridc^
com.adt.po.User WHERE user.name=:name"; %;'~%\|dZM
Query query = getSession().createQuery 2$iw/r
QZ#3Bn%B5
(querySentence); :l4^iSf
query.setParameter("name", name); ysL0hwir
return query.list(); s87 a%
} ,!jR:nApE
<` #,AVH
/* (non-Javadoc) +yt 6.L
* @see com.adt.dao.UserDAO#getUserCount() N&x@_t""
*/ >\Z lZ
publicint getUserCount()throws HibernateException { mf+K{y,L
int count = 0; z9I1RXV
String querySentence = "SELECT count(*) FROM :fl*w""V@
bb*c+XN0
user in class com.adt.po.User"; hT\p)w
Query query = getSession().createQuery P>.Y)$`r
t>XZ3
(querySentence); fF\*v
count = ((Integer)query.iterate().next )J{.Cx<E
GU2]/\W*a
()).intValue(); o-L|"3P
return count; ^ b=5 6~[
} EPQ&?[6
M4R%Gr,La
/* (non-Javadoc) e6Wl7&@6
* @see com.adt.dao.UserDAO#getUserByPage f S(^["*G
6'S5sRA
(org.flyware.util.page.Page) YCtIeq%
*/ `MN&(!&C*
publicList getUserByPage(Page page)throws ]kyle3#-~
pHq{S;R2G
HibernateException { YhEiN. ~
String querySentence = "FROM user in class =c
:lS&B
Rc$=+K#
com.adt.po.User"; "(9=h@@Y"
Query query = getSession().createQuery wa9'2a1?
Ej-=y2j{g
(querySentence); Sn;/;^@(\
query.setFirstResult(page.getBeginIndex()) n%7A;l!{
.setMaxResults(page.getEveryPage()); ?,.HA@T%
return query.list(); \Mobq
} E|KLK4]
BnY\FQ)K
} V5hp
Y ]
95_[r$C
N:m@D][/sW
<|mE9u
,e}mR>i=e
至此,一个完整的分页程序完成。前台的只需要调用 B iVd
ka
=e"H1^Ml
userManager.listUser(page)即可得到一个Page对象和结果集对象 gEcnn.(S
8 /:X&
&
的综合体,而传入的参数page对象则可以由前台传入,如果用 mBYS"[S(
JS<e`#c&
webwork,甚至可以直接在配置文件中指定。 okd
``vG
Dx9$H++6$X
下面给出一个webwork调用示例: | 7t=\
java代码: )Mm;9UA
w*|= k~z
Sn{aHH
/*Created on 2005-6-17*/ n_e}>1_
package com.adt.action.user; ,U} 5
@vVRF
Z
import java.util.List; 3j[w
-Lfp
#n6FQ$l8m
import org.apache.commons.logging.Log; *y":@T
import org.apache.commons.logging.LogFactory; %[+a[/
import org.flyware.util.page.Page; %fexuy4
wN/*|?`Z
import com.adt.bo.Result; .j'@K+<45
import com.adt.service.UserService; s!nSE
import com.opensymphony.xwork.Action; F$"MFdc[
'<*CD_2t-
/** .:#_5K
* @author Joa C[Y%=\6'0
*/ Q"l"p:n%n
publicclass ListUser implementsAction{ I_jM-/3b
mmpr]cT@'k
privatestaticfinal Log logger = LogFactory.getLog
f4A4
$?CBX27AV
(ListUser.class); qr<-eJf
UH1S_:6
private UserService userService; &deZ
0|K/=dh5+
private Page page; 4EaSg#
.O@q5G
privateList users; EL2 hD$
#w%a
m`+
/* =+SVzK,+3
* (non-Javadoc) YokZar2a0
* }]Gi@Nh|o
* @see com.opensymphony.xwork.Action#execute() E'Fv *UA
*/ =2vMw]
publicString execute()throwsException{ /eU1(oo&`5
Result result = userService.listUser(page); =0!\F~
page = result.getPage(); Cnc\sMDJ\B
users = result.getContent(); {8*d;[X50
return SUCCESS; [EW$7 se~
} %Mb(
c+7
.5#tB*H
/** |R
&3/bEr
* @return Returns the page. $jUS[.S_|I
*/ b0zxT9
public Page getPage(){ U||w6:W5
return page; 7am/X.
} >TQBRA;'
GP7)m
/** HqnKpZ
* @return Returns the users. #$vhC u<I
*/ "Wn?8vR
publicList getUsers(){ P!4{#'_}
return users; fEv<W
} SceCucT
6yl;o_6:
/** )68fm\t(
* @param page ou,=MpXx*
* The page to set. 8y4D9_{
*/ -'p@ lk
publicvoid setPage(Page page){ *?R\[59
this.page = page; !=h|&Vta
} ma]F%E+$
057G;u/
/**
8.;';[
* @param users P9tQS"Rs
* The users to set. /qz "I-a
*/ 'Kso@St`o
publicvoid setUsers(List users){ E23 Yk?"
this.users = users; 4W//Oc@e
} XnI
;7J
wMPw/a;
/** X\$W'^ np
* @param userService ;KZtW
* The userService to set. fO|~Oz<S
*/ 0@FM^ejA#
publicvoid setUserService(UserService userService){ l
SVW}t
this.userService = userService; @BHS5^|
}
Sfoy8<j
} rM
>V=|9,
CAo )v,f
DP6{HR$L
J PzQBc5e
";S*[d.2tA
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 3}#XA+Z
b[[6X
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ;iC'{S
PVkN3J
么只需要: Pq J*
java代码: =[)N6XV 3
y!6:
,M/#Q6P0}
<?xml version="1.0"?> va/4q+1GfH
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork j_a~)o-p
6 XOu~+7
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 9M7(_E;)B
t{S{!SF4
1.0.dtd"> R;TEtu7
|gRgQGeB
<xwork> -IEP?NX
@<TfA>*VJ
<package name="user" extends="webwork- X-N$+[#
S_ -QvG2
interceptors"> };|PFWs
5 *pN<S
<!-- The default interceptor stack name ks#Z~6+3
e9_O/i N
-->
&pY G
<default-interceptor-ref u g:G9vjQ
i(f;'fb*
name="myDefaultWebStack"/> \Af|$9boHz
On.x~t
<action name="listUser" xE-c9AH
GWqY$YT
class="com.adt.action.user.ListUser"> dK;\`>8
<param jme5'FR
3
cW"VrFy9
name="page.everyPage">10</param> g\{! 21M
<result :k )<1ua
%1?V6&
name="success">/user/user_list.jsp</result> kdMS"iN8x
</action> |o=\9:wV
!>2\OSp!
</package> "`3^MvC
//u76nQ
</xwork> 7(g&z%
|UDD/e
X>GY*XU
5<?c_l9X^
rWfurB5f
T!xy^n]}
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 3&nc'
P "_}F
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。 L%O8vn^3
Fx99"3`3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^\kHEM|5v
(`y|AOs
y3[)zv
b
G5
*;yMD-=
我写的一个用于分页的类,用了泛型了,hoho o4 g
{ZM2WFpE
java代码: ^}7t:
7RFkHME
IS
9q 5/]
package com.intokr.util; ~5!TV,>ls
f<sPh>n
import java.util.List; d<'Yt|zt
YB3=ij!K
/** s1\BjSzk
* 用于分页的类<br> MHyl=5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> tMBy
^@p
* d~Ry>
* @version 0.01 H'\ EA(v+
* @author cheng bl>b/u7/6
*/ Cl.T'A$
public class Paginator<E> { {5IG3'
privateint count = 0; // 总记录数 Y4qyy\}
privateint p = 1; // 页编号 wBHDof
xX
privateint num = 20; // 每页的记录数 [gdPHXs
privateList<E> results = null; // 结果 BI^]juH-c
Uu:v4a
/** OHnjI>/
* 结果总数 5_C#_=E
*/ 5t#]lg[06'
publicint getCount(){ GXlg%
return count; MVd
3*
} :QL p`s
pvU oed\
publicvoid setCount(int count){ :Sn3|`HDm
this.count = count; >@Vr'kg+V
} [=F
|^KL
Jo$Dxa
z
/** ;/q6^Nk3A
* 本结果所在的页码,从1开始 6%INNIyAWa
* }Q^a.`h
* @return Returns the pageNo. *>$)#?t
*/ &p4<@k\L
publicint getP(){ AX RNV
return p; }/r%~cZ
} _:p_#3s$
}Y ];ccT
/** tRBK1h
* if(p<=0) p=1 =?Md&%j
* ^|;4/=bbs
* @param p '0$[Ujc
*/ }F`2$Q+CW
publicvoid setP(int p){ W*`6ero
if(p <= 0) ",V5*1w
p = 1; &E`Z_}~
this.p = p; "$pgmf2
} U?j> 28
K.1yncS^
/** slfVQ809
* 每页记录数量 (b}7Yb]#c
*/ nnl9I4-O
publicint getNum(){ O~'yP@&`
return num; J\D3fh97-
} $QBUnLOek&
z35Rjhj9
/** HWOH8q{f!
* if(num<1) num=1 N4jLbnA
*/ >!.9g
publicvoid setNum(int num){
#de^~
if(num < 1) -Ep6.v
num = 1; {~I_rlo n
this.num = num; }3y\cv0ct
} 4yv31QG$
RcP5].^T
/** q#3X*!)
* 获得总页数 ^(vd8 &71
*/ ?+=|{{l
publicint getPageNum(){ n`Iy7X
return(count - 1) / num + 1; (r\h dLX
} MXV4bgltT
P[ 8N58#
/** nn%xN\~<
* 获得本页的开始编号,为 (p-1)*num+1 D~&e.y/gHN
*/ /y|r iW
publicint getStart(){ bR,Iq}p
return(p - 1) * num + 1; p;=(-4\V}
} )1
j2
M6#(F7hB
/** [`\Qte%UH
* @return Returns the results. p,Hk"DSs%
*/ <t37DnCgI
publicList<E> getResults(){ In
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return results; ]_8 \g`"u
} 3y ,?>-
\hN2w]e
public void setResults(List<E> results){ RhmVHhj
this.results = results; !#qB%E]a
} uZI a-b
CHI(\DXNs
public String toString(){ ;g]+MLV9
StringBuilder buff = new StringBuilder r^^C9"
1Di&vpn0u
(); hj,x~^cS
buff.append("{");
|?A-?-
buff.append("count:").append(count); F|Q#KwN
buff.append(",p:").append(p); ^T,cXpx|
buff.append(",nump:").append(num); ZE`{J=,
buff.append(",results:").append 'v
X"l
]#n4A|&H
(results); NLY5L7
buff.append("}"); w,9F riW
return buff.toString(); 3v U (4}@
} P$I\)Q H
=C)1NJx&~
} 5K{h)* *5
OhEL9"\<
-m/4\D