Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }f6.eqBX4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +|#:*GZ
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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 egr@:5QwZ{
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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 YJ1P5u:
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分页支持类: &1w,;45
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java代码: 9F,jvCM63
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package com.javaeye.common.util; }jIb ^|#CD
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import java.util.List; tH W"eag
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publicclass PaginationSupport { -p%=36n
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publicfinalstaticint PAGESIZE = 30; 1ViDS
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privateint pageSize = PAGESIZE; m$@Cw Qj
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privateList items; sM?DNE^BvW
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privateint totalCount; dFFB\|e;0
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privateint[] indexes = newint[0]; g|n Pr)<
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privateint startIndex = 0; Ge97e/CY
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public PaginationSupport(List items, int }F1^gN&QF
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totalCount){ '4O1Y0K
setPageSize(PAGESIZE); :!r_dmJ
setTotalCount(totalCount); E~N}m7kTl/
setItems(items); -MOf[f^
setStartIndex(0); 0} {QQB
} kB :")$
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public PaginationSupport(List items, int RrRCT.+E
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totalCount, int startIndex){ OSq"q-Q
setPageSize(PAGESIZE); Ad`;O+/;
setTotalCount(totalCount); P+Hs6Q
setItems(items); \wnQ[UNjP
setStartIndex(startIndex); _{ ?1+
} !5{t1 oJ
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public PaginationSupport(List items, int pX2 Ki^)]
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totalCount, int pageSize, int startIndex){ P/ug'
setPageSize(pageSize); A\ LTAp(I
setTotalCount(totalCount); Ct.Q)p-wn
setItems(items); J#JZ^59lOS
setStartIndex(startIndex); AQ-PY
} IcaF4#
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publicList getItems(){ .Cm wR$u&
return items; .Mm8\].
} M6g!bK2l
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publicvoid setItems(List items){ 'rz*mR8
this.items = items; #X|'RL($
} H!s &]b
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publicint getPageSize(){ BWQ
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return pageSize; X,gXgx P\
} Y&+<'FA
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publicvoid setPageSize(int pageSize){ `Y$LXF~,Om
this.pageSize = pageSize; sV{[~U,|
} %n{E/06f
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publicint getTotalCount(){ 7';PI!$
return totalCount; JLs7[W)O
} OyTBgS G?a
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publicvoid setTotalCount(int totalCount){ kgYa0 e5
if(totalCount > 0){ YSeXCJ:Iy
this.totalCount = totalCount; 8)M .W
int count = totalCount / ^i@t OtS
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pageSize; B Q".$(c
q
if(totalCount % pageSize > 0) s8 3_Bd
count++; )eUb@Eu
indexes = newint[count]; UWmWouA
for(int i = 0; i < count; i++){ I`FH^=
indexes = pageSize * YY$K;t{dk
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i; 9 ?h)U|J?G
} [j-]n#E=9y
}else{ Cee?%NaTS
this.totalCount = 0; nCYicB
} ^
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} $|sRj!F
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publicint[] getIndexes(){ 'w!Hjq]$
return indexes; O/0m|~`iY
} +
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publicvoid setIndexes(int[] indexes){ n,n]V$HFGh
this.indexes = indexes; lSQANC'
} ']4sx_)S
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publicint getStartIndex(){ qhiQ!fMQ
return startIndex; V#5BZU-
} ~Kt.%K5lgt
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publicvoid setStartIndex(int startIndex){ +&Sf$t 1
if(totalCount <= 0) ?%;)> :3N
this.startIndex = 0; m#DC;(Pn
elseif(startIndex >= totalCount)
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this.startIndex = indexes ]<TgBo|
epz2d~;
[indexes.length - 1]; mltN$b%G=d
elseif(startIndex < 0) aBol9`6
this.startIndex = 0; Nluy]h
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else{ IO|">a6
this.startIndex = indexes S'2B
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[startIndex / pageSize]; 3Pkzzyk_|D
} O`~T:N|D
} >qCUs3}C{*
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publicint getNextIndex(){ >/}v8k 1v
int nextIndex = getStartIndex() + b pExYyt
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pageSize; s+o/:rrxY
if(nextIndex >= totalCount) zj"J~s;?
return getStartIndex(); [C/h{WPC-
else !</5 )B`5:
return nextIndex; "4}{Z)&R2
} d];E99}
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publicint getPreviousIndex(){ rEs,o3h?po
int previousIndex = getStartIndex() - @yS
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pageSize; zVJwmp^
if(previousIndex < 0) !<@k\~9^D
return0; B%cjRwO T
else )!){4c/
return previousIndex; sf7'8+wj>
} >\3=h8zw
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} H2|&
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抽象业务类 j`ggg]"&$
java代码: S1*n4w.H
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/** r9z/hm}E
* Created on 2005-7-12 ;40!2P8t
*/ @kRe0:t
package com.javaeye.common.business; jQC6N#L
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import java.io.Serializable; rh?!f(_@
import java.util.List; |j<b?
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import org.hibernate.Criteria; oq(um:m
import org.hibernate.HibernateException; asmMl9)(`
import org.hibernate.Session; T6%*t#8r
import org.hibernate.criterion.DetachedCriteria; 9<}d98
import org.hibernate.criterion.Projections; eHm!
import ,]42v?
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org.springframework.orm.hibernate3.HibernateCallback;
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import f-tjMa /_
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org.springframework.orm.hibernate3.support.HibernateDaoS K/
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upport; (,[m}Qb?!
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import com.javaeye.common.util.PaginationSupport; $ZH$x3;
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public abstract class AbstractManager extends G*3O5m
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HibernateDaoSupport { #ZeZs 31
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privateboolean cacheQueries = false; o5@
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privateString queryCacheRegion; !2>gC"$nv
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publicvoid setCacheQueries(boolean `.>2h}op
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cacheQueries){ Gdi1lYu6V
this.cacheQueries = cacheQueries; IM7k\
} 0bzD-K4WVd
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publicvoid setQueryCacheRegion(String 5E+l5M*(
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queryCacheRegion){ ''s]6Jjw
this.queryCacheRegion = )PVX)2P_C
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queryCacheRegion; %o.{h
} GL(R9Y
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publicvoid save(finalObject entity){ i$?i1z*c}
getHibernateTemplate().save(entity); XTXRC$B
} q{[}*%
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publicvoid persist(finalObject entity){ F'|D
getHibernateTemplate().save(entity); Xd!=1::
} Azxy!gDT"
^
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publicvoid update(finalObject entity){ "|gNNmr
getHibernateTemplate().update(entity); bT@3fuL4
} P"cc$lB~ I
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publicvoid delete(finalObject entity){ #O7|&DqF{
getHibernateTemplate().delete(entity); &|LZ%W0Fb
} cP`o?:
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publicObject load(finalClass entity, =iB0ak
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finalSerializable id){ wwF]+w%lOw
return getHibernateTemplate().load A84I*d
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(entity, id); u0^GB9q
} D[x0sly
l
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publicObject get(finalClass entity, (@vu/yN
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finalSerializable id){ I@08F
return getHibernateTemplate().get ]6v6&YV
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(entity, id); 9?:SxI;v
} -4mUGh1dy
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publicList findAll(finalClass entity){ l'fUa
return getHibernateTemplate().find("from S^]i
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" + entity.getName()); \SkCsE#H
} 6=3}gd5
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publicList findByNamedQuery(finalString ~vy_~|6s
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namedQuery){ B5hk]=Ud
return getHibernateTemplate iEux`CcJ.
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().findByNamedQuery(namedQuery); L&+XFntR
} d}GO(
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publicList findByNamedQuery(finalString query, ExqI=k`Zs
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finalObject parameter){ \::<]
return getHibernateTemplate S\JV96
Af pB=3
().findByNamedQuery(query, parameter); E)|fKds
} 2~AGOx
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publicList findByNamedQuery(finalString query, ^n"ve2
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finalObject[] parameters){
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return getHibernateTemplate {<5rbsqk
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().findByNamedQuery(query, parameters); / Li?;H
} m*tmmP4R
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publicList find(finalString query){ qd6XKl\5
return getHibernateTemplate().find '9>z4G*Td
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(query); {wiw]@c8
} !U>711$
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publicList find(finalString query, finalObject 6H\3
id8a#&t]
parameter){ nyD(G=Q5
return getHibernateTemplate().find BY.'0,H=k
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(query, parameter); MQ9 9fD$
} $rD&rsx6
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public PaginationSupport findPageByCriteria +FRXTku(
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(final DetachedCriteria detachedCriteria){ cd)yj&:?Bt
return findPageByCriteria %Ak"d+OH4
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); SxcNr5F
} n,SD JsS^
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public PaginationSupport findPageByCriteria T},Nqt<
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(final DetachedCriteria detachedCriteria, finalint xG@zy4
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startIndex){ fmILkXKz
return findPageByCriteria jXB<"bw
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(detachedCriteria, PaginationSupport.PAGESIZE, Ufd{.o[{-
6|+I~zJ88
startIndex); ;0( |06=
} rTT Uhd
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public PaginationSupport findPageByCriteria /MKcS%/H/
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(final DetachedCriteria detachedCriteria, finalint WQv%57+
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pageSize, 3Z;`n,g
finalint startIndex){ p "EQ6_f
return(PaginationSupport) gF,9Kv~
ue@ fry
getHibernateTemplate().execute(new HibernateCallback(){ |fkz=*rn
publicObject doInHibernate eS{lr4-]
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(Session session)throws HibernateException { {{w5F2b((%
Criteria criteria = gBGUGjVj
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detachedCriteria.getExecutableCriteria(session); }w^Hm3Y^&
int totalCount = ^3C8GzOsO
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((Integer) criteria.setProjection(Projections.rowCount A
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6 Ty;m>j
()).uniqueResult()).intValue(); `3m7b!0k
criteria.setProjection J24<X9b
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(null); D&KRJQ/
List items = 1Ys6CJ#
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criteria.setFirstResult(startIndex).setMaxResults |Y?1rLC
HfEU[p7)
(pageSize).list(); tJ`tXO
PaginationSupport ps = w6(E$:#d
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new PaginationSupport(items, totalCount, pageSize, P Llad\
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startIndex); 3.>M=K~09
return ps; #InuN8sI
} 2>3#/I9Y
}, true); +j
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} 6V)P4ao
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public List findAllByCriteria(final }wZ9#Ll
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DetachedCriteria detachedCriteria){ 5nC#<EE
return(List) getHibernateTemplate |Xz-rgkQ
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().execute(new HibernateCallback(){ ahQdBoj
publicObject doInHibernate IJ >qs8
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(Session session)throws HibernateException { NH+?7rf8
Criteria criteria = L|O[u^
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detachedCriteria.getExecutableCriteria(session); !c+,OU[
return criteria.list(); EY'kIVk
} lr[U6CJY
}, true); 2H+!78
} _M[@a6?
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public int getCountByCriteria(final t&m8 V$Q
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DetachedCriteria detachedCriteria){ Yl}'hRp
Integer count = (Integer) +ZOjbI)
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getHibernateTemplate().execute(new HibernateCallback(){ U4`6S43ki
publicObject doInHibernate zl8O @g
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(Session session)throws HibernateException { V?pqKQL0
Criteria criteria = YQ/
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detachedCriteria.getExecutableCriteria(session); !V/Vy/'`*
return C]/]ot0%t
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criteria.setProjection(Projections.rowCount $=&a0O#
&!Sq6<!v2
()).uniqueResult(); [\|`C4@3a
} (@wgNA-P
}, true); EyU 5r$G
return count.intValue(); I'W`XN
} MPa F
} `p qj~s
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用户在web层构造查询条件detachedCriteria,和可选的 5D9n>K4|
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 l 1C'<+2j!
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PaginationSupport的实例ps。 jTSN`R9@
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ps.getItems()得到已分页好的结果集 ~bC-0^/
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ps.getIndexes()得到分页索引的数组 LsW7JIQd
ps.getTotalCount()得到总结果数 M{(g"ha
ps.getStartIndex()当前分页索引 HRP
ps.getNextIndex()下一页索引 ^~dBO%M^
ps.getPreviousIndex()上一页索引 UQ[!k 6
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Z+8Q{|Ev
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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 E}qW'
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一下代码重构了。 3rdrNc
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我把原本我的做法也提供出来供大家讨论吧: )s-[d_g
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首先,为了实现分页查询,我封装了一个Page类: q7#4e?1
java代码: g]$e-X@k
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/*Created on 2005-4-14*/ Fy6(N{hql
package org.flyware.util.page; !4Oj^yy%
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/** x^sSAI(
* @author Joa eE=}^6)(*
* ;#)vw;XR
*/ RA_gj lJi
publicclass Page { D(X:dB50@
_n~[wb5J
/** imply if the page has previous page */ %tK^&rw%
privateboolean hasPrePage; `T#Jiq E
7M.TLV!f]
/** imply if the page has next page */ A
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privateboolean hasNextPage; f)_k_ <
)/:j$aq
/** the number of every page */ @r130eLh
privateint everyPage; c'!+]'Lr
Vb57B.I
/** the total page number */ XI5TVxo(q
privateint totalPage; \Bvy~UeE)>
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/** the number of current page */ r9
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privateint currentPage; U,g)N[|
|a|##/
/** the begin index of the records by the current lWyg_YO@
n1Z*wMwC
query */ 8V?*Bz-4`
privateint beginIndex; }VU7wMk
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/** The default constructor */ A[hvT\X
public Page(){ eWk
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} :OKU@l|
7`P1=`..
/** construct the page by everyPage s
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* @param everyPage s$3WJ'yr
* */ e~1$x`DH
public Page(int everyPage){ 77/j}Pxh
this.everyPage = everyPage; }C'h<%[P
} 0l'"idra
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/** The whole constructor */ c#L.I
public Page(boolean hasPrePage, boolean hasNextPage, b~td^
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int everyPage, int totalPage, C"cBlru8B
int currentPage, int beginIndex){ @-% .+
this.hasPrePage = hasPrePage; .a_xQ]eQ
this.hasNextPage = hasNextPage; (L
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this.everyPage = everyPage; 8(@Y@`/
this.totalPage = totalPage; /4Sul*{hc
this.currentPage = currentPage; hmES@^n!_
this.beginIndex = beginIndex; ;kLp}CqV
} !#TM%w
UNhM:!A
/** @"vTz8oY@
* @return 3f)!RKS9q
* Returns the beginIndex. eFz!`a^dX
*/ JfVGs;_,
publicint getBeginIndex(){ nK>D& S_!
return beginIndex; ( jtkY_
} Wg[ThaZ
}Zp5d7(@w
/** )%Lgo${[;
* @param beginIndex ;yDXo\gm
* The beginIndex to set. p}MH LM
*/ _>/OqYR_jQ
publicvoid setBeginIndex(int beginIndex){ Vd+5an?
this.beginIndex = beginIndex; LT:*K!>NOL
} W't.e0L<6
gVpp9VB
/** &Tn7
* @return wg{Y6XyH
* Returns the currentPage. /e50&]2w
*/ vy{YGT
publicint getCurrentPage(){ nTH!_S>b(Y
return currentPage; 0qk.NPMB0
} #M=d)}[
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/** z!
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* @param currentPage =:pN82.G
* The currentPage to set. I.L8A|nZ
*/ S$%Y{
publicvoid setCurrentPage(int currentPage){ ]zR,Y=
#
this.currentPage = currentPage; ~glFB`?[
} MnT+p[.
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/** 7).zed^
* @return 2apQ4)6#[H
* Returns the everyPage. i'NN
*/ pTzfc`~xv
publicint getEveryPage(){ ' $5o5\
return everyPage; GcA!I!j/
} a&~]77)
)`gE-udR
/** Q=cbHDB
* @param everyPage :O{oVR
* The everyPage to set. `Ef&h V
*/ ^><B5A>;
publicvoid setEveryPage(int everyPage){ ,O}2LaK.O
this.everyPage = everyPage; :fE*fU@
} `<kV)d%xEF
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/** {r?qI
* @return ^_^rI+cTX1
* Returns the hasNextPage. "yV)&4)
*/ $N`uM
publicboolean getHasNextPage(){ ?FRQ!R
return hasNextPage; OJ\rT.{
} TAn.5
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/** SsF
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* @param hasNextPage $/uNV1]o
* The hasNextPage to set. t?j2Rw3f`I
*/ hhvP*a_J
publicvoid setHasNextPage(boolean hasNextPage){ -!p-nk@9|
this.hasNextPage = hasNextPage; ,9;d"ce
} dj0`Q:VZ
v^_<K4N`
/** R(sa.Q\D4
* @return r
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* Returns the hasPrePage. b1{XGK'
*/ fMFlY%@t
publicboolean getHasPrePage(){ 4MOA}FZ~
return hasPrePage; ,.+"10=N.
} D3emO'`gQ
vDAv/l9
/** pY9>z;qD
* @param hasPrePage 8E!I9z
* The hasPrePage to set. TAt9+\'
*/ ,`JXBI~
publicvoid setHasPrePage(boolean hasPrePage){ oFeflcSz
this.hasPrePage = hasPrePage; B<Ynx_95
} Eh)VU_D
"rA:;ntz
/** fJ3qL#'
* @return Returns the totalPage. YMx
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* ;Q.g[[J/p
*/ {@u}-6:wAT
publicint getTotalPage(){ m 5NF)eL
return totalPage; ;,h*s,i
} IBzHXa>75
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/** Ueyt}44.e2
* @param totalPage g loo].z
* The totalPage to set. OQh36BM
*/ r4xq%hy
publicvoid setTotalPage(int totalPage){ B&m?3w
this.totalPage = totalPage; 6YZ&>`a^
} ,b@0Qa"
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} NOa.K)^k
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 m`c(J1Et
~QsQ7SAs
个PageUtil,负责对Page对象进行构造: ::vw1Es
java代码: +G_6Ek4
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/*Created on 2005-4-14*/ j$]t`6gG
package org.flyware.util.page; z~oGd,
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import org.apache.commons.logging.Log; EVj48
import org.apache.commons.logging.LogFactory; 'eo2a&S2D
g-% uw[pf
/** +>OEp*
j
* @author Joa M{7EFTy!y
* _pNUI{De
*/ "7)F";_(^
publicclass PageUtil { ryx<^q
@ec QVk
privatestaticfinal Log logger = LogFactory.getLog I01On>"@7
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(PageUtil.class); 't{=n[
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/** |U^
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* Use the origin page to create a new page 2uWzcy ?F
* @param page 5Kv=;o=U
* @param totalRecords wrn[q{dX
* @return ?k_=?m
*/ _'AIXez7q
publicstatic Page createPage(Page page, int y::;e#.
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totalRecords){ #OWwg`AWv
return createPage(page.getEveryPage(), ~ilbW|s?=k
(p14{
page.getCurrentPage(), totalRecords); N"t,6tH
} aXC`yQ?
)hQNIt3o_
/** i%*x7zjY{
* the basic page utils not including exception Y=3Y~
1}8e@`G0.]
handler NE9e brK
* @param everyPage I/WnF"yP
* @param currentPage r 'jVF'w
* @param totalRecords _n}!1(xYa`
* @return page b9y
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*/ K?T)9
publicstatic Page createPage(int everyPage, int V7401@F
2z[Pw0#V
currentPage, int totalRecords){ $LRFG(
everyPage = getEveryPage(everyPage); ydns_Z
currentPage = getCurrentPage(currentPage); #zy,x
int beginIndex = getBeginIndex(everyPage, *qb`wg
Op%^dwVG(v
currentPage); u khI#:[
int totalPage = getTotalPage(everyPage, 1C$^S]v%a
D}"GrY5
totalRecords); >; W)tc,
boolean hasNextPage = hasNextPage(currentPage, Y,(eu*Za
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^
totalPage); <O>Q;}>gfc
boolean hasPrePage = hasPrePage(currentPage); Zo0&<QWj
,XA;S5FE
returnnew Page(hasPrePage, hasNextPage, sa#"@j)
everyPage, totalPage, NOS5bm&-
currentPage, @ ~sp:l
6PMu;#
beginIndex); y
ph
} p[o2F5 T2
#^v5Eo
privatestaticint getEveryPage(int everyPage){ 3mJHk<m8T
return everyPage == 0 ? 10 : everyPage; ]owH [wvX
} A:NY:#uC
56bB~=c
privatestaticint getCurrentPage(int currentPage){ WJ.PPq>]F
return currentPage == 0 ? 1 : currentPage; X2e|[MWkp
} s{q2C}=$?D
Pdn.c1[-a
privatestaticint getBeginIndex(int everyPage, int D\`$
W;-Qze\D
currentPage){ u%h<5WNh<
return(currentPage - 1) * everyPage; _+;x4K;
} z{n=G
r\NnWS J
privatestaticint getTotalPage(int everyPage, int J5o"JRJ"
So8P8TCK
totalRecords){ tRv#%>fj
int totalPage = 0; XW#4C*5?d
Lw#hnLI.
if(totalRecords % everyPage == 0) J`mp8?;%
totalPage = totalRecords / everyPage; .Nf*Yqs0
else +'Ge?(E4_
totalPage = totalRecords / everyPage + 1 ; 2)8lJXM$L
k{bba=<
return totalPage; q/3}8BJ
} 8EE7mEmLH
3Q ]MT
privatestaticboolean hasPrePage(int currentPage){ q@!:<Ra,){
return currentPage == 1 ? false : true; rb_G0/R
} ZE\t{s0
_N]yI0k(
privatestaticboolean hasNextPage(int currentPage, ,H%\+yn{
eQLa .0
int totalPage){ =_1" d$S&
return currentPage == totalPage || totalPage == ld?M,Qd
JIQzP?+?
0 ? false : true; O:x=yj%^
} 8zGzn%^
82=][9d #
1Jd: %+T
} 08`
@u4
@E)XT\;3
^$L/Mv+
zR
.MXr
7RLh#D|
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]S[r$<r$
ZV U9 t
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 kU
Flp
ec0vg.>p
做法如下: ZRHTvxf
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 hB.dqv]^
j;y|Ys)I
的信息,和一个结果集List: c1<g!Q&E
java代码: 7/1S5yUr|
TXa XJIp
4|e#b(!
/*Created on 2005-6-13*/ Ov|j{}=L=9
package com.adt.bo; ]@P*&FRcZ
DEs?xl]zO
import java.util.List; /{U{smtdFl
4Klfnki
import org.flyware.util.page.Page; QXz!1o+"
S&Sf}uK
/** zXD@M{
* @author Joa
4[ra
*/ S'O0'5U@
publicclass Result { JU@$(
+ ND9###
private Page page; e)7)~g54
%;5hHRA
private List content; H5AY6),
Q.\>+4]1&&
/** QD<4(@c5|
* The default constructor ayD\b6Z2.
*/ [GuDMl3hC
public Result(){ \f
LBw0
super(); C;5}/J^E
} 1fy{@j(W
=FbfV*K9
/** g)9/z
* The constructor using fields -0`hJ_(
* n`,Q:
* @param page kUt9'|9!
* @param content m&q;.|W
*/ hF~B&^dd.
public Result(Page page, List content){ ]| yH8 m
this.page = page; twtDyo(\
this.content = content; ,fw[ J
} J]0#M:w&
0- UeFy
/** {P-PH$ E-
* @return Returns the content. z!+<m<
*/ a}K+w7VY\
publicList getContent(){ l)8 V:MK
return content; -?RQ%Ue
} s]iOC6v
@_Zx'mTI
/** 6`C27
* @return Returns the page. 7|-xM>L$A
*/ $ZRN#x@
public Page getPage(){ >D<=9G(a
return page; ;$QJnQ"R
} a{+oN
$
DR /)hAE
/** vt
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* @param content >I?Mi{'a
* The content to set. Bkc-iC}F
*/ XV>6;!=E
public void setContent(List content){ 4m*(D5Y=|
this.content = content; $<4Ar*i
} DBUwf1=qj
mz*z1`\7v\
/** X$9QW3.M
* @param page ~@8d[Tb
* The page to set. Yg[IEy
*/ S nHAY<
publicvoid setPage(Page page){ l5[xJH
this.page = page; ".%LBs~$
} ;ZJ,l)BNO
} PHvjsA%"
/09=Tyy/\
\6 hL W_q1
Q/c
WV
Lf#G?]@
2. 编写业务逻辑接口,并实现它(UserManager, _6!/}Fm
aS vE
UserManagerImpl) (NdgF+'=
java代码: !yX<v%>_0
>U<nEnB$?
yk<jlVF$j
/*Created on 2005-7-15*/ N o(f0g.
package com.adt.service; 2.D!4+&
/8}+#h)[
import net.sf.hibernate.HibernateException; Ye2];(M
V(u2{4gZ
import org.flyware.util.page.Page; C|\^uR0
d~jtWd|?
import com.adt.bo.Result; aT#{t{gkA
hPz
df*(8
/** {*;]I?9Al
* @author Joa C..2y4bA}
*/ OLNn3
J
publicinterface UserManager { "t:.mA<v
fVUBCu
public Result listUser(Page page)throws e6HlOGPVQH
tR*W-%
HibernateException; _]UDmn[C
9*;isMkq<
} ;j U-<
-]\E}Ti
df6Ν4L
xzl4v=7
I~LQ1_
java代码: MLBg_<
}Tr83B|
x7Rq|NQ
/*Created on 2005-7-15*/ t;dQ~e20
package com.adt.service.impl; : .o=F`W
o
U}t'WU
import java.util.List; sNfb %r
P9"D[uz
import net.sf.hibernate.HibernateException; #)A?PO2
ckN(`W,xp
import org.flyware.util.page.Page; E#$_uZ4
import org.flyware.util.page.PageUtil; pq?[ wp"
n,jE#Z.D
import com.adt.bo.Result; ./nYXREO|
import com.adt.dao.UserDAO; udD*E~1q
import com.adt.exception.ObjectNotFoundException; 7 G[ GHc>
import com.adt.service.UserManager; # )mkD4
[gkRXP[DGs
/** ru/zLj:
* @author Joa I^O:5x>[l
*/ "1!.^<V*
publicclass UserManagerImpl implements UserManager { RA/ =w&
8U<.16+5Q
private UserDAO userDAO; mXU?+G0
aI{@]hCo
/** ~|Ih
JzDt
* @param userDAO The userDAO to set. "aWX:WL&}s
*/ ONN{4&7@<
publicvoid setUserDAO(UserDAO userDAO){ |g\. 5IM#W
this.userDAO = userDAO; #~URLN
} ro&Y7m
M-Z6TL
/* (non-Javadoc) $sc8)d\B
* @see com.adt.service.UserManager#listUser y:|.m@
j1
?Y0$X>nm
(org.flyware.util.page.Page) (2S!$w%
*/ Gj7QGIKx
public Result listUser(Page page)throws =*:[(Py1
W|H4i;u
HibernateException, ObjectNotFoundException { ay:\P.`5)
int totalRecords = userDAO.getUserCount(); NkA6Cp[Q,1
if(totalRecords == 0) h`EH~ W0:z
throw new ObjectNotFoundException ;;y@z[ >
0^!,[oh6*
("userNotExist"); i. u15$
page = PageUtil.createPage(page, totalRecords); Ag>>B9
List users = userDAO.getUserByPage(page); ;%rs{XO9
returnnew Result(page, users); bm tJU3Rm
} -wtTq
ph'
p*AP 'cR
} 7o965h
@8M'<tr<z
7:VEM;[d
-Ty<9(~S
nF. ;LM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 #>E3' 5b
J"D&q
询,接下来编写UserDAO的代码: nXM9Px!
3. UserDAO 和 UserDAOImpl: lNh=>DPu
java代码: ]*g ss'N
A|
gs Uh
!8
wid&
/*Created on 2005-7-15*/ SA`J.4yn
package com.adt.dao; } `>J6y9
,WO%L~db
import java.util.List; t7*G91Hoq&
mq{$9@3
import org.flyware.util.page.Page; )WP]{ W)r
>uyeI&z
import net.sf.hibernate.HibernateException; c69U1
s=q%:uCO
/** sxN>+v11z
* @author Joa c?p0#3%L#
*/ 1%SJ1oY
publicinterface UserDAO extends BaseDAO { |~/3u/
^^4K/XBve
publicList getUserByName(String name)throws W;OYO
Jm]]>K8.3V
HibernateException; [.#p
f
gK2.;>
publicint getUserCount()throws HibernateException; {p#l!P/
K)9j
je
publicList getUserByPage(Page page)throws H#kAm!H
+Dq|l}
HibernateException; VGTeuu5i
HC9vc,Fp
} M]6w^\4j9
c]%;^)
@o4z3Q@
fXF=F,!t
]Efh(Gb]
java代码: :>tF_6
`eMrP`
F1?CqN M
/*Created on 2005-7-15*/ 12:h49AP
package com.adt.dao.impl; YZ"+c&V"
L;.VEz!
import java.util.List; ]b0zkoD9<
Njy9 JX
import org.flyware.util.page.Page;
w2uRN?
9D{u,Q V
import net.sf.hibernate.HibernateException; ;e#>n!<u
import net.sf.hibernate.Query; eHVdZ'%x
v5&xY2RI7
import com.adt.dao.UserDAO; ~h>rskJ_
hb /8Q
/** h"VpQhi
* @author Joa dAYI D E
*/ Dh\S`nfFq
public class UserDAOImpl extends BaseDAOHibernateImpl S\!
a"0$
}|Hw0z P.
implements UserDAO { 8Ehy9<
G?Qe"4
.
/* (non-Javadoc) L?3VyBE
* @see com.adt.dao.UserDAO#getUserByName l]a^"4L4`o
W\I$`gyC/
(java.lang.String) 4)z3X\u|Z2
*/ T8,k77
publicList getUserByName(String name)throws ALE808;|
D:YN_J"kV
HibernateException { l1-4n*fU
String querySentence = "FROM user in class -vv
$:%*gY4~76
com.adt.po.User WHERE user.name=:name"; 5z9r S<
Query query = getSession().createQuery
s0C?Bb}?
'`M#UuU
(querySentence); -{yDk$"
query.setParameter("name", name); DHh+%|e
return query.list(); SBCL1aM
} _/8_,9H
|Q5H9<*
/* (non-Javadoc) k9*J*7l-m
* @see com.adt.dao.UserDAO#getUserCount() ax-=n (
*/ ^;V}l?J_s
publicint getUserCount()throws HibernateException { QE7+rBa
int count = 0; 0=N4O!X9
String querySentence = "SELECT count(*) FROM vbr~<JT=
6obQ9L c
user in class com.adt.po.User"; 7j@^+rkr3f
Query query = getSession().createQuery LFEp
/`7 I K
(querySentence); E0sbU<11
count = ((Integer)query.iterate().next "_nX5J9
+G5'kYzJ
()).intValue(); 4ggVj*{v
return count; z{Hz;m:*_
} $?H]S]#|}.
2.StG(Y!
/* (non-Javadoc) 68vxI|EZ
* @see com.adt.dao.UserDAO#getUserByPage ?~F]@2)5w
2"T8^r|U
(org.flyware.util.page.Page) 98D{{j92
*/ X?KGb{
publicList getUserByPage(Page page)throws Y
h^WTysBn
2B6^]pSk
HibernateException { EG F:xl
String querySentence = "FROM user in class 9|J8]m?x
kA1RfSS
com.adt.po.User"; pWMiCXnW
Query query = getSession().createQuery D"`%|`O
{@Blj3 ;w}
(querySentence); X }m7@r@
query.setFirstResult(page.getBeginIndex()) '9^E8+=|
.setMaxResults(page.getEveryPage()); }R`8h&J
return query.list(); zXj>K3M
} dj?G.-
V8-4>H}Cb/
} YH6snC$u
H"2 U)HJl
G
i$
Sv.KI{;v$
r`?&m3IOP
至此,一个完整的分页程序完成。前台的只需要调用 b0y-H/d/}
G!AICcP^
userManager.listUser(page)即可得到一个Page对象和结果集对象
=Ov9Kf
0v;ve
的综合体,而传入的参数page对象则可以由前台传入,如果用 R|/Wz/$1A
`ffj8U
webwork,甚至可以直接在配置文件中指定。 Z$Z`@&U=
2}D,df'W4
下面给出一个webwork调用示例: ].LJt['%8
java代码: f&K}IM8& #
Q]!6uA$A
cL6 6gOEL
/*Created on 2005-6-17*/ wG_4$kyj
package com.adt.action.user; (:ZPt(1
;_x2Ymw
import java.util.List; C#Y,r)l
4DvdEt
import org.apache.commons.logging.Log; .8-PB*vb
import org.apache.commons.logging.LogFactory; )8:n}w
import org.flyware.util.page.Page; <inl{CX/
b21}49bHN
import com.adt.bo.Result; k"t>He
import com.adt.service.UserService; C,[L/!
import com.opensymphony.xwork.Action; P~&O4['<
TLy;4R2Nn
/** &q.)2o#Q.
* @author Joa O ,l\e3;
*/ &u&2D$K,tp
publicclass ListUser implementsAction{
}K?F7cD
HS7R lU^
privatestaticfinal Log logger = LogFactory.getLog MY&<)|v\
TV<Aj"xw
(ListUser.class); pH^ z
b7Yq_%+
private UserService userService; %cS#+aK6M'
aWdUuid
private Page page; nZe\5`
AmZuo_
privateList users; bG52s
~Hs=z$
/* cnbo+U
* (non-Javadoc) /;+oz
* 5Lw{0uLr
* @see com.opensymphony.xwork.Action#execute() 2ed@HJu
*/ d"Bo8`_
publicString execute()throwsException{ .Xi2G@D
Result result = userService.listUser(page); T)`gm{T
page = result.getPage(); #uB[&GG}W
users = result.getContent(); Yi[4DfA
return SUCCESS; D^N[=q99&e
} 8:~b
&>
miPmpu!
/** 8`a,D5U:
* @return Returns the page. S3; lKr
*/ \{lE0j7}h
public Page getPage(){ hX&-/fF+f
return page; #0(fOHPQ
} <8$Md4r
qv.n9 9?]
/** av)?>J~;
* @return Returns the users. $kv@tzO
*/ {Wh BoD
publicList getUsers(){ 8*vFdoE_oO
return users; li@kLh
} Urn
:u
AjV
/** tO7I&LNE
* @param page bZu$0IG
* The page to set. L,6MF,vx
*/ 6I"C~&dt
publicvoid setPage(Page page){ A^8x1ydZ
this.page = page; Mg+4huT
} -gB{:UYi3
nVNs][
/** @Zj&`/
* @param users HXyFj
* The users to set. Q@3B{
*/ !h?=Wv
==]
publicvoid setUsers(List users){ ZxI]I1)
this.users = users; 2av*o~|J*:
} Zct!/u9 Q
z1#oWf{*
/** ,^HS`!s[ E
* @param userService (N7O+3+G
* The userService to set. SijS5irfk
*/ E_]k>bf\
publicvoid setUserService(UserService userService){ '\
XsTs#L
this.userService = userService; 6oYIQ'hc
} g(nK$,c
} 0juDuE?
(V8?,G >
%TDXF_.[
J,9%%S8/C
;|;iCaD a+
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, 1b8c67j[
Jb9F=s+
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 ~+=E"9Oo
UUGe"]V^g:
么只需要: YlrB@mE0n$
java代码: ]r!QmWw~V
6A.P6DW
{79qtq%W{
<?xml version="1.0"?> *O5:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork l!/!?^8|f
>GmN~"iJ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- QTfu: m{
RvR:e|
1.0.dtd"> d[S#Duz<&
%Sul4: D#
<xwork> Nkx0CG*
'Wtf>`
<package name="user" extends="webwork- I
ld7}R
g1ytT%]
interceptors"> dGU8+)2cn
K0v.3
<!-- The default interceptor stack name ?3Pazc]+|
JA< :K0
--> jAZ >mo[
<default-interceptor-ref 1g~y]iQ
A*R n<{U
name="myDefaultWebStack"/> o _(0
Ox~ 9_d
<action name="listUser" l0. FiO@_Q
bb}?h]a
class="com.adt.action.user.ListUser"> z(rK^RT
<param h07eEg
l^
Rm0t_
name="page.everyPage">10</param> JCNk\@0i*
<result l1|~
}I]W'<jY
name="success">/user/user_list.jsp</result> ifvU"l
</action> GZ"&L?ti
ydB$4ZB3[
</package> )d:K:YXt
g#|oif9o
</xwork> obj!I7
dHq#
McP~}"!^
:PUK6,"5]O
6e<^oH
Gnk|^i;t
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 6{8/P'@/Zz
05"qi6tncz
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。 F3Ap1-%z
OT;cfkf7
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 -zTEL(r
BJgDo
Xo8DEr
<}]{~y
rd">JEK;;
我写的一个用于分页的类,用了泛型了,hoho rw]yKH
XGhwrI ^
java代码: xHe^"LL
VGB-h'
VKNp,Lf
package com.intokr.util; `R0Y+#$8h
vtZ?X';wh
import java.util.List; >D~w}z/fk
1AT'S;`
/** pqH4w(;
* 用于分页的类<br> FQ!Oxlq,Q
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 8kS~ENe?o
* sl^n6N
* @version 0.01 @mNJ=mEV
* @author cheng 9x[ U$B
*/ +6oG@
public class Paginator<E> { jq[x DwPG
privateint count = 0; // 总记录数 ;NP[_2|-,
privateint p = 1; // 页编号 R*\~k%Z
privateint num = 20; // 每页的记录数 r:NH6tAL
privateList<E> results = null; // 结果 &XtRLtgS
Hd374U<8]T
/** tt{`\1q
* 结果总数 ]4o?BkL
*/ oq. r\r
publicint getCount(){ ??(Kwtx{
return count; qv uxhz F
} &[~[~m|
`.8UKSH+
publicvoid setCount(int count){ V^2-_V]8
this.count = count; \K}aQKB/j
} 8YKQItK
~#Aa Ldq
/** r)8z#W>s
* 本结果所在的页码,从1开始 "xn|zB
* LABNj{=D!
* @return Returns the pageNo. :Y^I]`lR"
*/ ]u0Jd#@
publicint getP(){ a_{6Qdl
return p; 1eD.:_t4
} :<%vE !$
@)b^^Fp
/** ;(S|cm'>}
* if(p<=0) p=1 r.<JDdj
* Uouq>N
* @param p wS%zWdsz
*/ 02pplDFsM
publicvoid setP(int p){ hfv%,,e
if(p <= 0) /WYh[XKe
p = 1; dhtb?n{
this.p = p; OpQ8\[X+
} KuXkI;63J>
H`el#tt_
/** NnOI:X {
* 每页记录数量 gc,Ps
*/ 8^vArS;
publicint getNum(){ P#*n3&Uu
return num; *Ru2:}?MpS
} %E.S[cf%8&
gt@SuX!@{^
/** Q1T@oxV
* if(num<1) num=1 jI0]LD1k
*/ Ag6uR(uI
publicvoid setNum(int num){ uLK(F
B
if(num < 1) z mbZ
num = 1; tN2 W8d
this.num = num; LwQH6 !;[
} yC"Zoa6YZ
CjKRP;5
/** TGpSulg7
* 获得总页数
W_}/ O'l{
*/ '\t7jQ
publicint getPageNum(){ O]ZC+]}/
return(count - 1) / num + 1; q~O>a0f0
} 75AslL?t
61|B]ei/
/** mf2Mx=oy
* 获得本页的开始编号,为 (p-1)*num+1 p:tN642
*/ km4g}~N</
publicint getStart(){ 9I kUZW
return(p - 1) * num + 1; jCQho-1QN
} K(3&27sGN
P^zy; Qs7
/** A{(T'/~"
* @return Returns the results. 41}/w3Z4
*/ DxfMqH[vs
publicList<E> getResults(){ ls @5^g
return results; Ay%:@j(E
} wv^b_DR
(Oq Hfv
public void setResults(List<E> results){ 4swKjN
&
this.results = results; 1Is%]6
} GA@ Ue9
c/'M#h)"
public String toString(){ 5#!ogKQ(i
StringBuilder buff = new StringBuilder [%~^kq=|
[gZDQcU
(); k%Eh{dA
buff.append("{"); i| 4_m
buff.append("count:").append(count); xYwkFB$$*
buff.append(",p:").append(p); `xIh\q
buff.append(",nump:").append(num); tW(+xu36
buff.append(",results:").append )eq}MaW+j
H&K3"Ulw
(results); 85hQk+Bu4
buff.append("}"); 0x71%=4H^x
return buff.toString(); y||@?Y
} "5|\X<f
lsFfb'>
} H"D5e
q^]tyU!w
?Pnx~m{%*