Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (7q^FtjA#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 I
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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 x(r+P9f\<
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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 5h_5Z~
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分页支持类: b6W#SpCF
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java代码: X.J
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package com.javaeye.common.util; }ymvC
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import java.util.List; ]if;A ) '
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publicclass PaginationSupport { (.^8^uc7X
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publicfinalstaticint PAGESIZE = 30; LF=c^9t
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privateint pageSize = PAGESIZE; !]DuZ=
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privateList items; VO9f~>`(
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privateint totalCount; g,?\~8-c
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privateint[] indexes = newint[0]; @l,{x|00
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privateint startIndex = 0; BjD&>gO)
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public PaginationSupport(List items, int m "]!I~jd
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totalCount){ swZpWC
setPageSize(PAGESIZE); [
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setTotalCount(totalCount); [h", D5
setItems(items); *)%dXVf
setStartIndex(0); &:8T$UV
} GVObz?Z]SB
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public PaginationSupport(List items, int M.k|bh8
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totalCount, int startIndex){ (t74a E pi
setPageSize(PAGESIZE); 8kbBz
setTotalCount(totalCount); Y+qus
setItems(items); qc-C>Ra
setStartIndex(startIndex); |BJqy/
} z6Z='=pT
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public PaginationSupport(List items, int Y(z}[`2
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totalCount, int pageSize, int startIndex){ !fZLQc
setPageSize(pageSize); {y/-:=S)A
setTotalCount(totalCount); \\iK'|5YG
setItems(items); (HSw%e
setStartIndex(startIndex); ]PVto\B=
} RIo'X@zb
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publicList getItems(){ QZ0R :TY
return items; w{P6i<J
} 62NkU)u
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publicvoid setItems(List items){ `(T!>QVW+g
this.items = items; 4
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} SY8U"Qc;9
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publicint getPageSize(){ P' FKk<
return pageSize; Qg{WMlyOP
} FG _,
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publicvoid setPageSize(int pageSize){ kpT>G$s~gy
this.pageSize = pageSize; &:#A+4&
} ~9i qD
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publicint getTotalCount(){ ]j1
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return totalCount; V
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} ,Z4^'1{D
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publicvoid setTotalCount(int totalCount){ !3?~#e{_
if(totalCount > 0){ rBD2Si=
this.totalCount = totalCount; cl2ze
int count = totalCount / .r*#OUC
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pageSize; @:IL/o*
if(totalCount % pageSize > 0) xx6S`R6:
count++; $$~a=q,P[
indexes = newint[count]; 1!s!wQgS
for(int i = 0; i < count; i++){ &$Ci}{{n#
indexes = pageSize * "_oLe;?$c
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i; jRwa0Px(
} mOSCkp{<e
}else{ \3:
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this.totalCount = 0; 6.UKB<sV
} 1::LN(`<
} K
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publicint[] getIndexes(){ }2mI*"%)\u
return indexes; GM77Z.Y
} E7gL~4I
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publicvoid setIndexes(int[] indexes){ ^Bn1;
this.indexes = indexes; PgTDjEo
} ktWZBQY
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publicint getStartIndex(){ vQcUaPm\$
return startIndex; :Ip~)n9t
} K~$ 35c3M
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publicvoid setStartIndex(int startIndex){ DUQ9AT#3
if(totalCount <= 0) *H?t;,\
this.startIndex = 0; `TkbF9N+
elseif(startIndex >= totalCount) 67fIIXk&
this.startIndex = indexes 2$
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[indexes.length - 1]; m.Twgin
elseif(startIndex < 0) :5G$d%O=2
this.startIndex = 0; 4"z;CGE7
else{ r
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this.startIndex = indexes D|"sE>
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[startIndex / pageSize]; 2>ys2:z
} RpU Lm1b
} 5W|u5AIw
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publicint getNextIndex(){ hO%Y{Gg
int nextIndex = getStartIndex() + we
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pageSize; $>|?k$(x
if(nextIndex >= totalCount) (%Ng'~J\|
return getStartIndex(); 1"M"h_4
else y>%W;r)
return nextIndex; nQ!N}5[z'
} /^~p~HKtx
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publicint getPreviousIndex(){ E}Ljo
int previousIndex = getStartIndex() - \?r$&K]4
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pageSize; &bn*p.=G
if(previousIndex < 0) hl*MUD,
return0; eS*
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else IC\E,m
return previousIndex; V;P1nL4L
} {a[Uv
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} " S ?Km
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抽象业务类 7 FEzak'
java代码: gQu\[e%mVo
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/** )hePN4edj
* Created on 2005-7-12 }<E sS
*/ 5%EaX?0h+
package com.javaeye.common.business; /\6}SG;
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import java.io.Serializable; Dr4?Ow
import java.util.List; WW)_Wh
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import org.hibernate.Criteria; qxRT1B]{Wx
import org.hibernate.HibernateException; D7%^Ly
import org.hibernate.Session; yjeqv-7
import org.hibernate.criterion.DetachedCriteria; Bi'I18<
import org.hibernate.criterion.Projections; ,oC={^l{
import I:r($m
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org.springframework.orm.hibernate3.HibernateCallback; ?aP1
import q]2}UuM|U
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org.springframework.orm.hibernate3.support.HibernateDaoS UDhwnGTq(l
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upport; FRb&@(;
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import com.javaeye.common.util.PaginationSupport; /%2:+w
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public abstract class AbstractManager extends V22q*/iV
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HibernateDaoSupport { aa%Yk"V@
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privateboolean cacheQueries = false; 95_[r$C
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privateString queryCacheRegion; <|mE9u
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publicvoid setCacheQueries(boolean B iVd
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cacheQueries){ AT2NC6{M
this.cacheQueries = cacheQueries; 8 /:X&
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} J"m%q\'
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publicvoid setQueryCacheRegion(String ]L5Z=.z&
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queryCacheRegion){ >FK)p
this.queryCacheRegion = yt]Oj*nn0K
(ouRf;\6$8
queryCacheRegion; wz*)L
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} 5$(b3]
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publicvoid save(finalObject entity){ NgDZ4&L
getHibernateTemplate().save(entity); eLe,=
}
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publicvoid persist(finalObject entity){ j]cXLY
getHibernateTemplate().save(entity); t-?KKU8
} uIVTs9\
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publicvoid update(finalObject entity){ D}k-2RM2k
getHibernateTemplate().update(entity); '#pMEVP
} r7]?g~zb
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publicvoid delete(finalObject entity){ 3Vb=6-|
getHibernateTemplate().delete(entity); Mp DdJ,
} < e7<t9
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publicObject load(finalClass entity, |wyJh"4!
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finalSerializable id){ l,^i5t'
return getHibernateTemplate().load q9g[+*9]$
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(entity, id); rU2YMghE
} R
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publicObject get(finalClass entity, Lk8W&|;0|
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finalSerializable id){ E)rOlh7
return getHibernateTemplate().get O,V6hU/ *
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(entity, id); 76u/WC>B
} G{&yzHAuae
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publicList findAll(finalClass entity){ c"QkE*
return getHibernateTemplate().find("from Bp=oTCG
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" + entity.getName()); e$FAhwpon
} D=q;+,Pc
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publicList findByNamedQuery(finalString tehI!->l
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namedQuery){ 6S&=OK^
return getHibernateTemplate g~$GE},,
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().findByNamedQuery(namedQuery); Ok~W@sYST
} >TQBRA;'
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publicList findByNamedQuery(finalString query, w50Bq&/jX
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finalObject parameter){ I]WeZ,E
return getHibernateTemplate *]E7}bqb
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().findByNamedQuery(query, parameter); Vm,f3~
} ftI+#0?[!
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publicList findByNamedQuery(finalString query, +ia(%[
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finalObject[] parameters){ )68fm\t(
return getHibernateTemplate ou,=MpXx*
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().findByNamedQuery(query, parameters); #pm-nU%|_j
} *?R\[59
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publicList find(finalString query){ mrLx]og,
return getHibernateTemplate().find y
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(query); EV?47\~
} d;NFkA(df
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publicList find(finalString query, finalObject ah!O&ECh
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parameter){ *|,ykb>
return getHibernateTemplate().find w;SH>Ax:
|q.:hWYFpM
(query, parameter); rJc)<OZjT
} G=bP<XF
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public PaginationSupport findPageByCriteria pJ*#aH[ySP
Mn }Z9S[
(final DetachedCriteria detachedCriteria){ ("JV:u.L+
return findPageByCriteria 1J{z}yPHc
gt t$O
(detachedCriteria, PaginationSupport.PAGESIZE, 0); w#G=Z_Tt
} _AFt6\
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public PaginationSupport findPageByCriteria ?lwQne8/
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(final DetachedCriteria detachedCriteria, finalint o"ah\"#el
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startIndex){ #G ,
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return findPageByCriteria `j!2uRFe>
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(detachedCriteria, PaginationSupport.PAGESIZE, j_a~)o-p
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startIndex); iZq@W3GL
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} noUZ9M|hz
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public PaginationSupport findPageByCriteria %}ApO{
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(final DetachedCriteria detachedCriteria, finalint 9X{nJ"
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pageSize, L5 k>;|SA
finalint startIndex){ hte9l)
return(PaginationSupport) c>i*HN}Z|
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getHibernateTemplate().execute(new HibernateCallback(){ F)5B[.ce
publicObject doInHibernate !|:q@|-
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(Session session)throws HibernateException { ~j&:)a'^
Criteria criteria = k-ex<el)#
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detachedCriteria.getExecutableCriteria(session); $-9@ /%Y
int totalCount = S.F=$z.%
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((Integer) criteria.setProjection(Projections.rowCount yDyeP{
lQ<n
dt~
()).uniqueResult()).intValue(); Qhr]eu;z
criteria.setProjection F3 l^^Mc
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(null); B{o\RNU
List items = -J7,Nw
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criteria.setFirstResult(startIndex).setMaxResults @ Rb1)$~#
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(pageSize).list(); //u76nQ
PaginationSupport ps = ;{q) |GRF
q>:&xR"ra
new PaginationSupport(items, totalCount, pageSize, E e\-q
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startIndex); .yfqS|(
return ps; w$;*~Qc
} r=H\4%P4
}, true); 2au(8IWu
} Nx (pJp{S
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public List findAllByCriteria(final kbT-Oz 2
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DetachedCriteria detachedCriteria){ 4Z~Dxo
return(List) getHibernateTemplate ^21f^>k(
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().execute(new HibernateCallback(){ |Sv #f2`
publicObject doInHibernate :+^$?[6]
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(Session session)throws HibernateException { PW//8lsR
Criteria criteria = iN4'jD^oP
Qp{-!*
detachedCriteria.getExecutableCriteria(session); 6ym)F!t8l
return criteria.list(); |wb(rua
} hG;=ci3EE
}, true); y'O{8Q8T
} 8U:dgXz
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public int getCountByCriteria(final UG'U
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DetachedCriteria detachedCriteria){ .d!*<`S|
Integer count = (Integer) 3R:i*8C
<.(/#=2
getHibernateTemplate().execute(new HibernateCallback(){ z slEUTj)
publicObject doInHibernate 1HWJxV"
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(Session session)throws HibernateException { UR2)e{RXg
Criteria criteria = A^@ <+?
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detachedCriteria.getExecutableCriteria(session); LqsJHG
return ]bE?n.NwZ
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criteria.setProjection(Projections.rowCount N&h!14]{Z
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()).uniqueResult(); to|9)\
} RZh)0S>J
}, true); 4bzn^
return count.intValue(); 4"(zi5`e
} "s<lLgi
} ~[y+B0I3
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@CI6$
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用户在web层构造查询条件detachedCriteria,和可选的 _1c_TM h}9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 s'Q^1oQM2h
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PaginationSupport的实例ps。 ^|;4/=bbs
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ps.getItems()得到已分页好的结果集 }F`2$Q+CW
ps.getIndexes()得到分页索引的数组 iQ"F`C
ps.getTotalCount()得到总结果数 "$pgmf2
ps.getStartIndex()当前分页索引 K.1yncS^
ps.getNextIndex()下一页索引 slfVQ809
ps.getPreviousIndex()上一页索引 (b}7Yb]#c
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 W(4?#lA2W
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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 AV3,4u
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一下代码重构了。 =T}uQ$X
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]
我把原本我的做法也提供出来供大家讨论吧: AK?j1Pk
xU<lv{m`D
首先,为了实现分页查询,我封装了一个Page类: NP*0WT_gB
java代码: wT yM9wz&
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/*Created on 2005-4-14*/ ZUW>{'[K
package org.flyware.util.page; #'h CohL
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/** iRHQRdij
* @author Joa R_n-&d'PP
* 0N ;d)3
*/ fEv36xb2S
publicclass Page { :ygz/L
!T. @
/** imply if the page has previous page */ vGT.(:\-,
privateboolean hasPrePage; kk+8NwM1
D07u?
/** imply if the page has next page */ *S_Iza #&x
privateboolean hasNextPage; y<d#sv(s
Asu"#sd
/** the number of every page */ Lo9?,^S
privateint everyPage; Vnb#N4vR
3[Iw%% q
/** the total page number */ )6+W6:
privateint totalPage; *G41%uz
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/** the number of current page */ mP[u[|]
privateint currentPage; 26K~m@
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/** the begin index of the records by the current $7d"9s\$"
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query */ ??V["o T
privateint beginIndex; qDb}b d5
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pk1M.+
/** The default constructor */ hiHp@"l<
public Page(){ We?:DM
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} [Cp{i<C
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/** construct the page by everyPage &}1)]6q$
* @param everyPage ,$-PC=Ti(
* */ L9oZ7 o
public Page(int everyPage){ G)7sXEe
this.everyPage = everyPage; q/?_djv
} Q2?qvNZ
Q~_x%KN/`
/** The whole constructor */ }L9j`17
public Page(boolean hasPrePage, boolean hasNextPage, Kjw\SQ)2~
#KW:OFT
?~IZ{!
int everyPage, int totalPage, '7s!NF2
int currentPage, int beginIndex){ 54w-yY
this.hasPrePage = hasPrePage; a"0~_=
this.hasNextPage = hasNextPage; Z-(HDn
this.everyPage = everyPage; P\e%8&_U/
this.totalPage = totalPage; e,8-P-h~T
this.currentPage = currentPage; cC.DBYV+-
this.beginIndex = beginIndex; idy:Jei}
} dZmq
^ BKr0~4A
/** sN2l[Ous
* @return vE(Hy&Q&
* Returns the beginIndex. Dzr5qP?#
*/ z, [+
publicint getBeginIndex(){ {AUEVt
return beginIndex; )K~nZLULY
} ]mA?TwD
U w"
/** Xk'.t|
* @param beginIndex `l#g`~L
* The beginIndex to set. 8t%1x|!
*/ a0.XJR{T"
publicvoid setBeginIndex(int beginIndex){ I]X<L2
this.beginIndex = beginIndex; LKcrr;
} @HI5;z
}R$%MU5::
/** plfB}p
* @return I2'?~Lt
* Returns the currentPage. QUf_fe!,|
*/ gp=0;#4
4
publicint getCurrentPage(){ o1\8>Ew
return currentPage; &bQ^J%\
} 0i"OG( ,
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/** z/b*]"g,
* @param currentPage 4<|u~n*JF
* The currentPage to set. {SV$fl;
*/ zdCt#=QV?R
publicvoid setCurrentPage(int currentPage){ Za w+
this.currentPage = currentPage; X!Q"p$D4(
} CR<l"~X
2dfA}i>k
/** h%%'{^>~
* @return D#0}/
* Returns the everyPage. xXZN<<f59
*/ X*KT=q^?n
publicint getEveryPage(){ |4vk@0L
return everyPage; }_ E
} ]7;;uhn`
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/** xpz
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* @param everyPage dkjL;1
* The everyPage to set. Jp- hFD
*/ \Z8!iruN
publicvoid setEveryPage(int everyPage){ \B)<<[ $
this.everyPage = everyPage; wr`eBPu
} v|6fqG+Q\
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/** pN[i%\vh
* @return \XC1/LZQ
* Returns the hasNextPage. c{~*\&
*/ *L=CJg
publicboolean getHasNextPage(){ v&Kw
3!X#E
return hasNextPage; eC?N>wHH
} /1*\*<cs
_N6GV$Q
/** ":OXs9Yg
* @param hasNextPage SPBXI[[-
* The hasNextPage to set. =B 9U
*/ xQQ6D
publicvoid setHasNextPage(boolean hasNextPage){ o&=m]hKpQl
this.hasNextPage = hasNextPage; 6o!"$IH4
} ^IpS 3y
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/** WVZ\4y
* @return n):VuOjm
* Returns the hasPrePage. AOpfByw
*/ fOfp.`n
publicboolean getHasPrePage(){ FwyPmtBj
return hasPrePage; Hogr#Sn2
} |c)#zSv
ec|IT0;
/** {PZe!EQ
* @param hasPrePage 3iB8QO;pp
* The hasPrePage to set. Nbr{)h
*/ <T['J]k%
publicvoid setHasPrePage(boolean hasPrePage){ Ks4TBi&J
this.hasPrePage = hasPrePage; nN[,$`JD,
} [yz;OoA:;
I8m(p+Z=
/** E)Dik`Ccl
* @return Returns the totalPage. 1*Z}M%
* >QYxX<W
*/ @I%m}>4Jm
publicint getTotalPage(){ b+kb7
return totalPage; X:YxsZQ5Y
} Z=#!FZ{
"QMHY\C
/** ^VA)vLj@
* @param totalPage _Q QO&0Z
* The totalPage to set. =&vV$UtV
*/ %BL +'&q
publicvoid setTotalPage(int totalPage){ 4WLB,<b}
this.totalPage = totalPage; /SyiJCx0
} s;bqUY?LD
@^%# ]x,:
} _b+3;Dy
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akR*|iK#b
1Z`zdZs
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 !$j'F? 2>
3 Tt8#B
个PageUtil,负责对Page对象进行构造: k7j;'6
java代码: 56fcifXz@
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/*Created on 2005-4-14*/ nF=h|rN
package org.flyware.util.page; co:
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import org.apache.commons.logging.Log; Q.x3_+CX
import org.apache.commons.logging.LogFactory; x,n;GR
8ED6C"6
/** wuPx6hCl
* @author Joa \5Hfe;ny-~
*
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*/ @hk~8y]rz
publicclass PageUtil { 6b@:La
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privatestaticfinal Log logger = LogFactory.getLog Rt+s\MC^r
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(PageUtil.class); LcQ \d*
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/** Y#KgaZ7N
* Use the origin page to create a new page i),W1<A1
* @param page "/K44(^
* @param totalRecords zT.qNtU%
* @return U`xjau+
*/ w9vqFtj
publicstatic Page createPage(Page page, int [-Dx)N
&Prx=L`
totalRecords){ Nx~8]h1(
return createPage(page.getEveryPage(), y:xZ(RgfF
l2xM.vR
page.getCurrentPage(), totalRecords); *f1MgP*GKF
} tip\vS)
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/** -FwOX~s/'
* the basic page utils not including exception t|1?mH9
W@#Y/L:${
handler NT:p6(s^
* @param everyPage /aP`|&G,)
* @param currentPage DvU(rr\p
* @param totalRecords m+zzhv1
* @return page EiSS_Lc
*/ G> "w$Us
publicstatic Page createPage(int everyPage, int *U8Pjb1
(,[Oy6o
currentPage, int totalRecords){ sk9*3d5I
everyPage = getEveryPage(everyPage); q* +}wP
currentPage = getCurrentPage(currentPage); Ve<l7U;
int beginIndex = getBeginIndex(everyPage, fVw+8 [d0
$`mxOcBmQ
currentPage); fs\l*nBig
int totalPage = getTotalPage(everyPage, g$~ktr+%
Nw8lg*t"
totalRecords); =j6f/8
boolean hasNextPage = hasNextPage(currentPage, Dr&2qX!
@a+1Ri`)
totalPage); +g%kr~w=
boolean hasPrePage = hasPrePage(currentPage); Pr9$(6MX
Iell`;
returnnew Page(hasPrePage, hasNextPage, Y`w+?}(M
everyPage, totalPage, _uID3N%
currentPage, *zJ}=%)f
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beginIndex); YP/BX52v
} ;mu^WIj
V^[o{'+
privatestaticint getEveryPage(int everyPage){ hIE$u t +
return everyPage == 0 ? 10 : everyPage; oIN!3
}
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privatestaticint getCurrentPage(int currentPage){ [td)v,
return currentPage == 0 ? 1 : currentPage; -)PQ&[
} Hz `aj
^fa+3`>
privatestaticint getBeginIndex(int everyPage, int 7E6gXf.
x=(Q$Hl5
currentPage){ 'gI q_t|^
return(currentPage - 1) * everyPage; oSq4g{xvMH
} J4&d6[40
sA[hG*#/S
privatestaticint getTotalPage(int everyPage, int kZfa8wL]P
A}W)La\
totalRecords){ !RN(/ &%y
int totalPage = 0; j#rjYiYKy
/I(IT=kp
if(totalRecords % everyPage == 0) Y j;KKgk
totalPage = totalRecords / everyPage; ~dg7c{o5
else D6fry\
totalPage = totalRecords / everyPage + 1 ; >{C=\F#*L
rOHU)2
return totalPage; J'jwRn
} BIqZg$
TCWy^8LA
privatestaticboolean hasPrePage(int currentPage){ F
jsnFX;
return currentPage == 1 ? false : true; tJ;<=.n
} WBvh<wTw;
yPs4S?<s
privatestaticboolean hasNextPage(int currentPage, /}t>o*
x
p~Di\AQ/
int totalPage){ j51Wod<[
return currentPage == totalPage || totalPage == >+Z BQ]~
FxeDjAP
0 ? false : true; e)"]H*
} ?NkweT(
,T&=*q
QQ;<L"VW
} E{'{fo!#)
'#pY/,hVB
Myaj81
o_R<7o/d|
'RZ=A+% X
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。 3c#oK
>zx]%
W
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 <+o*"z\mI
1$mxMXNsJ
做法如下: 'Km
~3t
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2^RWGCEv
Va"H.]
的信息,和一个结果集List: $De1 4
java代码: P&I%!'<
A@M%}h
4j+FDc`
/*Created on 2005-6-13*/ ])Rs.Y{Q5
package com.adt.bo; @/jLN
nIc:<w]
import java.util.List; X)6}<A
'9d<vWg
import org.flyware.util.page.Page; [Ume^
nwSujD
/** $$'a
* @author Joa nz_=]PHO&
*/ 3>vSKh1z
publicclass Result { {P/ sxh:e
V;}kgWc1
private Page page; V}=%/OY?
T .#cd1b
private List content; k_d)
f0"N
/** LelCjC{`1
* The default constructor b~$B0o)
*/ CVxqNR*DN
public Result(){ -QPM$
super(); DpA"5RV
} }7Lo}}
d6RO2^
/** n`v;S>aT
* The constructor using fields a*
2*aH7
* j`H5S
* @param page e
*9c33
* @param content *49({TD6`
*/ {9mXJu$cc
public Result(Page page, List content){ MC\rx=cR\
this.page = page; m 0jm$>:Z
this.content = content; 5l_ >QB
} 7
k:w3M
U-h'a:
K
/** |aWeo.;c
* @return Returns the content. *aem5E`c
*/ skSs|slp
publicList getContent(){ Dqxtc|vo
return content; [v0[,K
} ~%gO +qD
SK][UxoHm
/** :2v^pg|
* @return Returns the page. c
qWX*&2_
*/ S<Rl?El<=
public Page getPage(){ 'J[n}r
return page; rHSA5.[1P
} %1JN%
Wnf3[fV6P
/** gC/~@Z8W]
* @param content S2APqRg*
* The content to set. [nYm-\M
*/ 2D'b7zPJ3
public void setContent(List content){ C4,;l^?=%
this.content = content; 44r@8HO1
} JyiP3whW
W'98ues%
/** E\$7tXQK6
* @param page ox|K2A
* The page to set. `S)*(s?T
*/ sLHUQ(S!
publicvoid setPage(Page page){ *- S/{
.&
this.page = page; !<EQVqj6
} DA9-F
} UgqfO(
QXaE2}}P
th
:I31
n7A %y2
{.r
jp`39
2. 编写业务逻辑接口,并实现它(UserManager, [c`u
?=^~(x?S
UserManagerImpl) %@q/OVnM
java代码: 31cC*
3QZ~t#,7ij
#&$a7L}
/*Created on 2005-7-15*/ tMy<MO)Ei
package com.adt.service; U07G&?/
tJ qd
import net.sf.hibernate.HibernateException; AiDV4lHr
=cP7"\
import org.flyware.util.page.Page; BH;7CK=7R
~ZxFL$<'3
import com.adt.bo.Result; )8,) &F
Sd9%tO9mf
/** (>)f#t[9J
* @author Joa 7^hwRZJ{
*/ Y%GIKtP
publicinterface UserManager { fR^aFT
:nLhg$wMs
public Result listUser(Page page)throws Yw!(]8PYdU
>}I BPC
HibernateException; Ho^rYz
2a,l;o$2&
} n){F
FM
bMCy=5
^Gt9.
n !oxwA!
Cg]Iz<<bE
java代码:
MYk%p'
Nn:>c<[
:~PzTUz
/*Created on 2005-7-15*/ cD 5^mxd%
package com.adt.service.impl; |to|kU
I_aSC 4
import java.util.List; gX'nFGqud
5 0KB:1(g
import net.sf.hibernate.HibernateException; OS{j5o
&pk&8_=f
import org.flyware.util.page.Page; -~HyzX\cZB
import org.flyware.util.page.PageUtil; bMjE@S&
ajJ+Jn\
import com.adt.bo.Result; 5h!ZoB)n
import com.adt.dao.UserDAO; WF&?OHf2
import com.adt.exception.ObjectNotFoundException; n7$21*,
import com.adt.service.UserManager; No(p:Snbo
q33Z.3R
/** ]!mC5Ea
* @author Joa +<TnE+>j
*/ cy%S5Rz
publicclass UserManagerImpl implements UserManager { ,x]xtg?
nyRQ/.3
private UserDAO userDAO; "4Bk
^DaP^<V
/** <q<kqy5s-R
* @param userDAO The userDAO to set. ,bU8S\8
*/ h+"UK=
publicvoid setUserDAO(UserDAO userDAO){ c&]nAn(
this.userDAO = userDAO; ch-.+p3
} 49Y_ze6L}
MEled:i
/* (non-Javadoc) >I&'Rj&Mc
* @see com.adt.service.UserManager#listUser R>CIEL
84|oqwZO
(org.flyware.util.page.Page) 3mCf>qj73
*/ VKtZyhK"h
public Result listUser(Page page)throws .^ o3
WKDa]({k%
HibernateException, ObjectNotFoundException { ,T<q"d7-#
int totalRecords = userDAO.getUserCount(); 'G|M_ e
if(totalRecords == 0) BJ$\Mb##3@
throw new ObjectNotFoundException %@Ow.7zh
+T,Yf/^Fn
("userNotExist"); aZBS!X
page = PageUtil.createPage(page, totalRecords); n72+X
List users = userDAO.getUserByPage(page); tpQ?E<O
returnnew Result(page, users); L^b /+R#
} 6!Z>^'6
p@Va`:RDW
} -w3KBlo
)B1gX>J\8
%+F%C=GqI
Yfa` }hQ
+yO^,{8SE
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 dF#`_!4pbf
BJ,D1E
询,接下来编写UserDAO的代码: I%#&@
3. UserDAO 和 UserDAOImpl: y2=`NG=
java代码: s(u,mtG
k __MYb
NB@TyU
/*Created on 2005-7-15*/ #eZm)KFQg
package com.adt.dao; [i 7^a/e
{%! >0@7
import java.util.List; $?FA7=_
&'{?Y;A
import org.flyware.util.page.Page; }r _d{nhi
SAUfA5|e
import net.sf.hibernate.HibernateException; W}0cM9 g
~REP@!\r^
/** =o? Q0
* @author Joa 7JL*y\'
*/ ~bsL
W:.'
publicinterface UserDAO extends BaseDAO { CA8N
S`?L\R.:
publicList getUserByName(String name)throws 6U!zc]>
^U@-Dp,k+
HibernateException; Mb
+
q8-*3K
publicint getUserCount()throws HibernateException; //O9}-
Ku3/xcu:My
publicList getUserByPage(Page page)throws o
/ i
W%
jph"94
HibernateException; 5U[bn=n
7~H.\4HB
} YuVg/ '=
^.:dT?@R
?K9zTas@
l
NhX)D^t
079mn/8;
java代码: "eOFp\vPr
c'Mi9,q
bayDdR4T
/*Created on 2005-7-15*/ E!SxO~
package com.adt.dao.impl; g71|t7Q
16Gp nb
import java.util.List; 1*vt\,G
wB0Ke
import org.flyware.util.page.Page; >/eV4ma"
EDAVU
import net.sf.hibernate.HibernateException; y%NZ(Y,v
import net.sf.hibernate.Query; =T3O; i
p+7ZGB
import com.adt.dao.UserDAO; PYPDK*Ie
uu`G<n
/** oD?c]}3
* @author Joa }bM=)eUfX
*/ DI,8y"!5
public class UserDAOImpl extends BaseDAOHibernateImpl !c#~g0H+
A!n)Fpk
implements UserDAO { ]Ac&h
aAP
W{js9$oJ
/* (non-Javadoc) gPYF2m
* @see com.adt.dao.UserDAO#getUserByName %`b
%TH^
XI8rU)q
(java.lang.String) ]%I}hjJ
*/ Oqy&V&-C
publicList getUserByName(String name)throws #OE]'k
Ss
#\LsM
~,
HibernateException { rh+2
7"
String querySentence = "FROM user in class Z<M?_<3
jJU9~5i?
com.adt.po.User WHERE user.name=:name"; l$mfsm|{:
Query query = getSession().createQuery SIr^\iiOB
)HPe}(ypt
(querySentence); Y-vLEIX=
query.setParameter("name", name); LkA_M'G
return query.list(); QT[yw6Z
} cq-UVk"Gl
:^92B?q
/* (non-Javadoc) hnD=DLW $
* @see com.adt.dao.UserDAO#getUserCount() <-avC/M$d
*/ Gj9WUv[P
publicint getUserCount()throws HibernateException { N sNk
int count = 0; v$_YZm{!<
String querySentence = "SELECT count(*) FROM :^H#i:4
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user in class com.adt.po.User"; RV{'[8gM
Query query = getSession().createQuery n(.U>_
P
!GL
kAV
(querySentence); n$z+g>~N
count = ((Integer)query.iterate().next BL?Bl&p(
s+RSAyU
()).intValue(); M+ljg&fy
return count; f 3t&Bcw$
} co-dq\P
:i8B'|DN5
/* (non-Javadoc) ']cRSj.
* @see com.adt.dao.UserDAO#getUserByPage g[ dI%
kEr;p{5
(org.flyware.util.page.Page) ,rZp(moj
*/ "T+oXK\B
publicList getUserByPage(Page page)throws +`D,7"{Eu
.
v
L4@_
HibernateException { G$T#ql
String querySentence = "FROM user in class FvTc{"w /
W!.vP~ >
com.adt.po.User"; x.ZW%P1
Query query = getSession().createQuery LH_rc
+#Q\;;FNP
(querySentence); X6`F<H`
query.setFirstResult(page.getBeginIndex()) &Bfgvws;
.setMaxResults(page.getEveryPage()); l*(Ml=
O{
return query.list(); ugT;NB
} zv>3Tc0R
:
#om6}
} {@tqeu%IM
@UgZZ
)!tqock*v
G+dQ" cI9
|MEu"pY)
至此,一个完整的分页程序完成。前台的只需要调用 g E#4 3
Sh(W s2b7
userManager.listUser(page)即可得到一个Page对象和结果集对象 'L1=:g.\i
tITx+i
的综合体,而传入的参数page对象则可以由前台传入,如果用 A.@/~\
IA$)E
webwork,甚至可以直接在配置文件中指定。 zUNWcv!& "
l]wjH5mz=i
下面给出一个webwork调用示例: 0[SJ7k19
java代码: S.Rqu+
S(nZ]QEG
+q NX/F
/*Created on 2005-6-17*/ BXx0Z
%e.3
package com.adt.action.user; t!S ja
9+!1jTGSkf
import java.util.List; |yT-N3H@
E` O@UW@
import org.apache.commons.logging.Log; ,-[e{=Cz
import org.apache.commons.logging.LogFactory; dH8^\s .F
import org.flyware.util.page.Page; '1u!@=.\G
fP:26pK^
import com.adt.bo.Result; h'D-e5i
import com.adt.service.UserService; #;*0 Pwe`
import com.opensymphony.xwork.Action; qC;1ND
miCW(mbO8
/** xP+HdA2X
* @author Joa |1z?#@BH
*/ eq<giHJM
publicclass ListUser implementsAction{ P}dhpU
vsDR@Y}k
privatestaticfinal Log logger = LogFactory.getLog *pMu,?uE
<XAW-m9SC
(ListUser.class); :p6.v>s8
bm Hl\?
private UserService userService; ;WG6|QgV?-
RXZ}aX[h
private Page page; n:i?4'-}
XX])B%*
privateList users; =^L?Sgg
nGvWlx
/* `EjPy>kM
* (non-Javadoc) _h2s(u
>\
* E,fG<X{
* @see com.opensymphony.xwork.Action#execute() _h7qS
*/ H7=[sL^
publicString execute()throwsException{ K@DK4{
Result result = userService.listUser(page); (sHvoE^q-
page = result.getPage(); h4\j=Np
users = result.getContent(); O
F|3y~z
return SUCCESS; EoOB0zo}Y+
} `fA|])3T
&-s/F`
/** X?Yp=%%
* @return Returns the page. 9~FB^3Nz_
*/ [p7cgHSMt
public Page getPage(){ }RT#V8oc
return page; '=^$;3Z
} l'#P:eW
<l,Kg
'v
/** S9'8rn!_
* @return Returns the users. $cUTe
*/ /N'|Vs,X
publicList getUsers(){ l_`DQ8L`
return users; >#jfZ5t
} R"0fZENTG
9*"Ae0ok1
/** YH%aPsi
* @param page T9,T'y>BD
* The page to set. oK! W<#
*/ zURob MpE#
publicvoid setPage(Page page){ 6)QJms
this.page = page; 'W>Zr}:
} iTgv8
w
N-np3k
/** [`u3SN/P
* @param users ^{vf|zZ _
* The users to set. /<\B8^yQ
*/ tCw.wDq3=
publicvoid setUsers(List users){ 6N^sUc0s
this.users = users; >>'t7U##
} 3Xun>ZQ-
?[|T"bE5[
/** 0A7 qO1%xw
* @param userService T==(Pw7R7
* The userService to set. &;D(VdSr9
*/ @ n-[bN
publicvoid setUserService(UserService userService){ KG5h$eM'
this.userService = userService; =h#3D?b0n
} bkZ~O=uv$-
} lQnl6j
cjd Z.jR2
ylEQeN
BgzER[g|q{
c|s*(WljY
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, ?4]#gCks
x9c/;Q&m
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 :Y{aa1
7Z(F-B
+j
么只需要: 1 >nl ]yO
java代码: gx*rxid
x@@U&.1_A
LHt{y3l]
<?xml version="1.0"?> ]Gm$0uS
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~sI$xX!
<NLor55.]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- #..-!>lY
b0~AN#Es
1.0.dtd"> N<xf=a+j
o9l =Q
<xwork> 6 +:Tv2
RawK9K_1
<package name="user" extends="webwork- 1>doa1
QTN
_Z#'
interceptors"> g' xR$6t
q=M\#MlL0'
<!-- The default interceptor stack name Bhy:"
r%#
$9}z^sGIM
--> P&ig.Og*
<default-interceptor-ref ?H c~ 3
1-Fz#v7p
name="myDefaultWebStack"/> Whf7J'
s[V$fvW
<action name="listUser" <By6%<JTn
p8>.Q/4
class="com.adt.action.user.ListUser"> V7zF5=w
<param m]bv2S+5 y
WhO;4-q)2
name="page.everyPage">10</param> H?dmNwkPY
<result PgKA>50a
1I?D$I>CV
name="success">/user/user_list.jsp</result> }HM8VAH
</action> 8-N8v
*0
RaKfYLw
</package> "%c\i-&t
k~(j
</xwork> I[~EQ{Iz
6AZJ,Q\E@
*cdr,AD?lH
He)<S?X-6
Wdt9k.hzN
"d a%@Zy
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 <&7KcvBn"4
TK )Kq
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 FkdG@7Xf
@quNVx(y
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 58H [sM4>
^y?7B_%:B#
vrtK~5K
%$b)l?!
Xd_86q8o
我写的一个用于分页的类,用了泛型了,hoho VrF(0,-Z`3
avR4#bfc
java代码: }lzyl*.
x?J-
{6k
't$(Ruw
package com.intokr.util; IT,TSs/Y
a pxZ}
import java.util.List; zMfr`&%e
`laaT5G\y
/** <a-I-~
* 用于分页的类<br> or_x0Q
* 可以用于传递查询的结果也可以用于传送查询的参数<br> la ~T)U7
* U!:Q|':=h
* @version 0.01 D6iHkDTg
* @author cheng ti:qOSIDTA
*/ %}+!%A.3
public class Paginator<E> { 8K!
l X
privateint count = 0; // 总记录数 kL.JrbM"
privateint p = 1; // 页编号 JM5w`=
privateint num = 20; // 每页的记录数 Z!TLWX"
privateList<E> results = null; // 结果 `~Eo;'( +^
Epm\=s
/** "5mdq-h(
* 结果总数 r5qp[Ss3F
*/ NymS8hxR
publicint getCount(){ =J0X{Ovn4z
return count; QE&rpF7l{
} PaF`dnJ
)%q]?@kB
publicvoid setCount(int count){ =,0E]MZ
this.count = count; QN_Zd@K*A
} Zx(VwB2
,?GEL>F
/** {g?$u
* 本结果所在的页码,从1开始 _B`'1tNx
* nB ?$W4
* @return Returns the pageNo. 7:U ^Ki
*/ G#ov2
publicint getP(){ \|Pp%U [
return p; (W3~r
} .jRp.U
etdI:N*x
/** gc-yUH0I
* if(p<=0) p=1 0c4H2RW
* i]8HzKuiW
* @param p =[!&&,c=
*/ \2#>@6Sqrl
publicvoid setP(int p){ +Zu*9&Cx
if(p <= 0) `}gjfu -'\
p = 1; cq`v8
this.p = p; fu3/ n@L
} [*U6L<JI
T] d9tX-
/** h#9X0u7j
* 每页记录数量 [z$th
*/ OD!b*Iy|
publicint getNum(){ 4y&%YLMpl
return num; !T/^zc;G
} {-IH?!&v
5BCHWX*y
/** Hc1S:RW
* if(num<1) num=1 :T(3!}4
*/ H8+7rM
publicvoid setNum(int num){ /t`s.!k
if(num < 1) dieGLA<5_X
num = 1; won;tO]\;@
this.num = num; Uk=jQfA*J
} b: UTq
7^
[(U:1&x&
/** X>^St&B}fC
* 获得总页数 X4LU/f<f
*/ iJE
$3
publicint getPageNum(){ VdpwZ
return(count - 1) / num + 1; (K"U# Zn
} Z-W>WR
MG<kvx~2
/** bcFG$},k
* 获得本页的开始编号,为 (p-1)*num+1 &U%AVD[
*/ ?s[ kUv+=
publicint getStart(){ =n>&Bl-Bl
return(p - 1) * num + 1; pIBL85Xe
} F)'kN2
.6Tan2[%
/** H^{Eh
* @return Returns the results. (LzVWz m
*/ 4 {JoeIRyz
publicList<E> getResults(){ :/
,h)h)|
return results; ehB (?
} !t/I
j ~o
f
QSP]?
public void setResults(List<E> results){ v<
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this.results = results; - Te+{
} SoX\S|}%6[
lt\.
)Y>4
public String toString(){ F]kn4zr
StringBuilder buff = new StringBuilder z97RNT|Y7U
`R@1Sc<*|
(); %fB]N
buff.append("{"); ^$-ID6
buff.append("count:").append(count); `6a
buff.append(",p:").append(p); b_2bg>|;
buff.append(",nump:").append(num); gE$D#PZa
buff.append(",results:").append xi|T7,\X
CX/ _\0G4
(results); LUSBRr8
buff.append("}"); k I
return buff.toString(); (/TYET_H
} xwK{}==U
3Au3>q,
} SPfz/ q{
W]b>k lp;
m{T:<:q~