Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Q?X>E3=U
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D.mHIsX6\
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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 >a}f{\Q
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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 5ms""LD/
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。 GH[wv<
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分页支持类: H9CS*|q6r
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java代码: @lvyDu6e
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package com.javaeye.common.util; )&!&AlLn
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import java.util.List; P+$:(I
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publicclass PaginationSupport { )wNP(
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publicfinalstaticint PAGESIZE = 30; ){UcS/GI=
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privateint pageSize = PAGESIZE; .?l\g-;=
:>=\. \
privateList items; Q1+dCCY#F
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privateint totalCount; l]5w$dded~
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privateint[] indexes = newint[0]; f!JS= N?3
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privateint startIndex = 0; =kuMWaD
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public PaginationSupport(List items, int [KxF'm z9
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totalCount){ Hhh0T>gi
setPageSize(PAGESIZE); e2A-;4?_
setTotalCount(totalCount); G["c\Xux
setItems(items); `*shF9.\C
setStartIndex(0); cCxBzkH6
} X*\J_
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public PaginationSupport(List items, int d N$Tf
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totalCount, int startIndex){ 15sp|$&`
setPageSize(PAGESIZE); rh^mJUh
setTotalCount(totalCount); r3PT1'P?L
setItems(items); cMOyo<F#^=
setStartIndex(startIndex); LSRk7'0
} b1($R[
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public PaginationSupport(List items, int =y!$/(H
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totalCount, int pageSize, int startIndex){ c??mL4$'N
setPageSize(pageSize); ruy}/7uf
setTotalCount(totalCount); \*<d{gZ~
setItems(items); `V04\05
setStartIndex(startIndex); >m$ 1+30X
} )h)]SF}
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publicList getItems(){ bR)(H%I
return items; {Ja!~N;3
} 1 |jt"Hz
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publicvoid setItems(List items){ ^t#&@-'(d
this.items = items; $\U4hHOo
} c-0#w=
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publicint getPageSize(){ %xyou:~0zs
return pageSize; (P:<t6;+
} #n8IZ3+
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publicvoid setPageSize(int pageSize){ w}YlVete
this.pageSize = pageSize; {Sj9%2'M)
} H|HYo\@F#
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publicint getTotalCount(){ q1KZ5G)6GJ
return totalCount; \}|o1Xh2
} Sxh]R+Xb
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publicvoid setTotalCount(int totalCount){ r<d_[?1N
if(totalCount > 0){ jIyB
this.totalCount = totalCount; ~S,,w1`
int count = totalCount / V:
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pageSize; JVSA&c%3
if(totalCount % pageSize > 0) VG
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count++; "[ZB+-|[0
indexes = newint[count]; /x
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for(int i = 0; i < count; i++){ }xh$T'M8
indexes = pageSize * :BV6y|J9O^
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i; _dhgAx-H)h
} #;2n;.a
}else{ )O@]uY
this.totalCount = 0; |}di&y@-JI
} MjC_ ( cs
} z)r=+ -
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publicint[] getIndexes(){ /~$WUAh
return indexes; 1`qMj0Y_
} IvtJ0
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publicvoid setIndexes(int[] indexes){ 6"&6`f
this.indexes = indexes; %_%Q8,W
} #W.#Hjpp
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publicint getStartIndex(){ heC/\@B
return startIndex; (<xfCH
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} 9 %I?).5
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publicvoid setStartIndex(int startIndex){ FW G6uKv
if(totalCount <= 0) 3@$,s~+ 3
this.startIndex = 0; VoWNW
elseif(startIndex >= totalCount) jk [1{I/
this.startIndex = indexes _n50C"X=&(
sg3OL/"
[indexes.length - 1];
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elseif(startIndex < 0) 9Hb6nm
this.startIndex = 0; tne ST.
else{ !C3MFm{B
this.startIndex = indexes |es?;s'
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[startIndex / pageSize]; K1+)4!}%U
} TE7nJ gm
} L>aLqQ3
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publicint getNextIndex(){ ?kH8Lw~{5W
int nextIndex = getStartIndex() + Z8@J`0x
xRzFlay8
pageSize; 1q:2\d]
if(nextIndex >= totalCount) jZ~n[
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return getStartIndex(); 2q=AEv/
else "8x8UgG
return nextIndex; CR"|^{G
} d\|?-hY`[
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publicint getPreviousIndex(){ R6kD=JY/!
int previousIndex = getStartIndex() - J\:R|KaP<p
}J:U=HJ
pageSize; :~tAUy":_*
if(previousIndex < 0) #FCnA
return0; Ybs\ES'?A
else >_-s8t=|
return previousIndex; zuJ@E=7
} KWowN;
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} /'l{E
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抽象业务类 lm-dW'7&
java代码: P3x= 8_#
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/** 4ew"
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* Created on 2005-7-12 N~goI#4
*/ (_mnB W
package com.javaeye.common.business; N `5,\TR2f
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import java.io.Serializable; K/j3a[.
import java.util.List; A@1W}8qY:
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import org.hibernate.Criteria; =jOv] /
import org.hibernate.HibernateException; {JZZZY!n2
import org.hibernate.Session; Tc>
import org.hibernate.criterion.DetachedCriteria; .w=/+TA
import org.hibernate.criterion.Projections; [!HEQ8 2g
import PV'x+bN5
}Jy8.<Gd^
org.springframework.orm.hibernate3.HibernateCallback; AS'R?aX|C
import /YW>*?"N
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org.springframework.orm.hibernate3.support.HibernateDaoS WM7oM~&{6
}Z@ovsG
upport; 9ifDcYl
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import com.javaeye.common.util.PaginationSupport; ?I_s0k I
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public abstract class AbstractManager extends p{amC ;cI$
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HibernateDaoSupport { 9YIM'q>`v
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privateboolean cacheQueries = false; R]c+?4J
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privateString queryCacheRegion; p
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publicvoid setCacheQueries(boolean Z&Pg"a?\
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cacheQueries){ Q]Y*K
this.cacheQueries = cacheQueries; q0i(i.h
} 8Wrh]egu1
!;&p"E|b#
publicvoid setQueryCacheRegion(String R]}}$R`j
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queryCacheRegion){ .zA^)qgL
this.queryCacheRegion = twL3\
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queryCacheRegion; nhB1D-
} gp};D
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publicvoid save(finalObject entity){ m,*QP*
getHibernateTemplate().save(entity); 8'r2D+Vwm
} [-65PC4aN
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publicvoid persist(finalObject entity){ "Gfh ,e
getHibernateTemplate().save(entity); q+H%)kF
} 6]V4muz#c
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publicvoid update(finalObject entity){ #a/5SZP
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getHibernateTemplate().update(entity); wa<MRt W=
} I
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publicvoid delete(finalObject entity){ /f:dv?!km
getHibernateTemplate().delete(entity); =)M/@T
} Hu\B"fdS
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publicObject load(finalClass entity, nOt&pq7
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finalSerializable id){ yh Yb'GK
return getHibernateTemplate().load s>B5l2Q4
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(entity, id); V, Z|tB^
} s1MErd
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publicObject get(finalClass entity, [;r)9mh7
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finalSerializable id){ ;kFDMuuO
return getHibernateTemplate().get *;l]8.
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(entity, id); )JDs\fUE
} 9A/\h3HrJ
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publicList findAll(finalClass entity){ #X%~B'
return getHibernateTemplate().find("from }6p@lla,%]
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" + entity.getName()); \l'm[jy>
} Lz`E;k^
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publicList findByNamedQuery(finalString oiF}?:7Q7
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namedQuery){ lW+\j3?Z$
return getHibernateTemplate :}Xll#.,m
j| v%)A
().findByNamedQuery(namedQuery); v0
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} Upc+Ukw
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publicList findByNamedQuery(finalString query, wg7V-+@i
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finalObject parameter){ @GBxL*e
return getHibernateTemplate Sc>,lIM
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().findByNamedQuery(query, parameter); ?zeJ#i
} ^WHE$4U`
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publicList findByNamedQuery(finalString query, _K`wG}YIE
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finalObject[] parameters){ HTVuStM8
return getHibernateTemplate *i\Qo
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().findByNamedQuery(query, parameters); na#CpS;pc
} qIVx9jNN
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publicList find(finalString query){ "oTHq]Ku
return getHibernateTemplate().find WB?jRYp
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(query); di?K"Z>
} G^~k)6v=m
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publicList find(finalString query, finalObject SFB~
->db
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parameter){ :V1W/c
return getHibernateTemplate().find MC?,UDNd%
gcE|#1>
(query, parameter); J,V9k[88
} )2pbpbWX>
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public PaginationSupport findPageByCriteria _4rFEYz$d
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(final DetachedCriteria detachedCriteria){ W}--p fG
return findPageByCriteria m`v2: S}
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); *}]Nf
} jq-p;-i
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public PaginationSupport findPageByCriteria 3
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(final DetachedCriteria detachedCriteria, finalint R%Qf7Q
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startIndex){ "JVkVp[5D+
return findPageByCriteria ks3`3q 7
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(detachedCriteria, PaginationSupport.PAGESIZE, " W!M[qBW
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startIndex); C+?Hm1
} 1LqoF{S:
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public PaginationSupport findPageByCriteria !,l9@eJQ
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(final DetachedCriteria detachedCriteria, finalint c|lu&}BS
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pageSize, tkVbo.[8K
finalint startIndex){ pA`+hQNN
return(PaginationSupport) nA?`BOe(
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getHibernateTemplate().execute(new HibernateCallback(){ XUM!Qv
publicObject doInHibernate VcAue!MN
*YW/_
(Session session)throws HibernateException { &K[_J
Criteria criteria = 8;z6=.4xtg
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detachedCriteria.getExecutableCriteria(session); @En^wN
int totalCount = g3Ec"_>P
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((Integer) criteria.setProjection(Projections.rowCount M^MdRu
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()).uniqueResult()).intValue(); \qR7mI/*
criteria.setProjection `Y
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(null); X-
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List items = 7q?9Tj3
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criteria.setFirstResult(startIndex).setMaxResults AcS|c:3MUy
O>qll6]{@
(pageSize).list(); `D>S;[~S7
PaginationSupport ps = ~Cl){8o
#OBJzf*p
new PaginationSupport(items, totalCount, pageSize, 6S\C}U/
>C7r:%
startIndex); xgABpikC^
return ps; rE iKi
} ~oI1zNz/
}, true); n/DP>U$I&
} N<f"]
@WJgWJm
public List findAllByCriteria(final /nyUG^5#{
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DetachedCriteria detachedCriteria){ ^cV;~&|.Xk
return(List) getHibernateTemplate $>*3/H
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().execute(new HibernateCallback(){ `o<'
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publicObject doInHibernate =2[7
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(Session session)throws HibernateException { )_1zRT| 9
Criteria criteria = =2Bg9!zW>
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detachedCriteria.getExecutableCriteria(session); dODt(J}%
return criteria.list(); #@^t;)|
} Q&MZN);.
}, true); 0*%Z's\M"
} iDMJicW!+F
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public int getCountByCriteria(final nNrPHNfqD
#rxVd
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DetachedCriteria detachedCriteria){ W"):-Wq
Integer count = (Integer) !O-T0O
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f
getHibernateTemplate().execute(new HibernateCallback(){ F_Z- 8>P
publicObject doInHibernate ;} und*q
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(Session session)throws HibernateException { .^N/peUq
Criteria criteria = @[5xq
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detachedCriteria.getExecutableCriteria(session); xm%Um\Pb7
return =jlt5 z
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criteria.setProjection(Projections.rowCount &Ts-a$Z7?S
O_$m!5ug
()).uniqueResult(); /<E5"Mm%
} 7.C;NT
}, true); *4_jA](
return count.intValue(); !v X D
} ^
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} iOwx0GD.n
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用户在web层构造查询条件detachedCriteria,和可选的 Mzsfo;kk+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 mu?Eco`~
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PaginationSupport的实例ps。 v[#9+6P=
hfnN@Kg?B}
ps.getItems()得到已分页好的结果集 _$=
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ps.getIndexes()得到分页索引的数组 .gG1kW A-
ps.getTotalCount()得到总结果数 R>,:A%?^b5
ps.getStartIndex()当前分页索引 &n6$rBr%
ps.getNextIndex()下一页索引 .%.9n\b
ps.getPreviousIndex()上一页索引 ,stN
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /DQc&.jK
M%1}/!J3
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Q>/C*@
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一下代码重构了。 I?"q/Ub~h
Vl%^H[]
我把原本我的做法也提供出来供大家讨论吧: ._8KsuJG
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首先,为了实现分页查询,我封装了一个Page类: \]P!.}nX#
java代码: _Dym{!t
A$#p%yb
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/
/*Created on 2005-4-14*/ xZ|Y?R5m
package org.flyware.util.page; GytXFL3`:
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/** YhOlxON
* @author Joa WA]c=4S
* ]Tkc-ez
*/ N-I5X2
publicclass Page { :!5IW?2
5QPM t^
/** imply if the page has previous page */ SG-'R1
J
privateboolean hasPrePage; }:u~K;O87
=
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/** imply if the page has next page */ (S xR`QP?,
privateboolean hasNextPage; Mu{;vf|j
Nc+,&R13m
/** the number of every page */ o4*+T8[|5
privateint everyPage; ;3\3q1oX
X>NhZ5\
/** the total page number */
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privateint totalPage; Zm=(+
f
(>`5z(X
/** the number of current page */ `)GrwfC
privateint currentPage; ~=8uN<
{Zh>mHW3
/** the begin index of the records by the current G
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6&bY} i^K
query */ H2
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privateint beginIndex; %Eb%V ($
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S}$r>[t
/** The default constructor */ ms!r ef4`+
public Page(){ e*bH0'; q
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} BNd^qB ?
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/** construct the page by everyPage fO0(Z
* @param everyPage F1jglH/MF)
* */ +n<k)E@>J
public Page(int everyPage){ ]%BWIqbr
this.everyPage = everyPage; dxZu2&gi
} S,<EEtXQ
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/** The whole constructor */ YqPQ%
public Page(boolean hasPrePage, boolean hasNextPage, ;]gP@ h/
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int everyPage, int totalPage, A5i :x$ww
int currentPage, int beginIndex){ ~zSCg|"r
this.hasPrePage = hasPrePage; GN!qyT
this.hasNextPage = hasNextPage; ?t+5s]
this.everyPage = everyPage; % ]I ZLJ
this.totalPage = totalPage; &^}6
9
this.currentPage = currentPage; |1ST=O7.LH
this.beginIndex = beginIndex; +)j1.X
} h$.:Uj8/
9lGOWRxR)
/** AX= 1b,s
* @return abJ"
[
* Returns the beginIndex. AJSx%?h:6
*/ qTAc[Ko
publicint getBeginIndex(){ ~mO62(8m
return beginIndex; W?eu!wL#p
} } ~"hC3w
x_c7R;C
/** %I-+Ead0i
* @param beginIndex F
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* The beginIndex to set. ;Ra+=z}>
*/ _R.B[\r@
publicvoid setBeginIndex(int beginIndex){ 8F:e|\SB#
this.beginIndex = beginIndex; HcedE3Rg
} 6_d.Yfbq
wKi^C8Z2
/**
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* @return I! > \#K
* Returns the currentPage. {X[ HCfJd
*/ m=:4`_0Q
publicint getCurrentPage(){ e|&6$A>4]
return currentPage; `5~ +,/Ys
} 81hbk((
.\8X[%K9nc
/** y_HN6
* @param currentPage T"&)&"W*U
* The currentPage to set. FL8g5I
*/ - !>}_AH
publicvoid setCurrentPage(int currentPage){ OvUI@,Ef
this.currentPage = currentPage; 4'6`Ll|iq
} o99pHW(E
^)?d6nI
/** #7ov#_2Jd
* @return 63.wL0~
* Returns the everyPage. c\ia6[3sX
*/ B 9T!j]'
publicint getEveryPage(){ Rb%%?*|
return everyPage; cuK,X!O
} zCOgBT~p
X^\>:<
/** t9Y=m6
* @param everyPage !<UJ6t}
* The everyPage to set. 7C$
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*/ cZ(elZ0~
publicvoid setEveryPage(int everyPage){ 0b/ WpP
this.everyPage = everyPage; "H&"(=
} j:}D Bk
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/** _[Vf547vS
* @return $8p7 D?Y
* Returns the hasNextPage. N? 5x9duK
*/ =7m}yDs6$
publicboolean getHasNextPage(){ Q 2A7mGN
return hasNextPage; i~3u>CT
} 3d-%>?-ee
hzI|A~MFB
/** A<6%r7&B'
* @param hasNextPage q~@]W=
* The hasNextPage to set. eeHP&1= 7
*/ 6<'rG''
publicvoid setHasNextPage(boolean hasNextPage){ "Tm[t?FMbe
this.hasNextPage = hasNextPage; mo1oyQg8
} nOQa_G]Gz
zNY)'
/** _{Sm k[
* @return M:P0m6ie
* Returns the hasPrePage. R(-<BtM!-
*/ }BiiE%a
publicboolean getHasPrePage(){ $2<d<Um~z
return hasPrePage; ]c&<zeX,
} 4GR!y)
{8R"O{
/** McoK@q;
* @param hasPrePage ~GuMlV8
* The hasPrePage to set. ifo7%XPcg
*/ 5OO'v07b
publicvoid setHasPrePage(boolean hasPrePage){ 4QIE8f
Y
this.hasPrePage = hasPrePage; 557(EM
} wHIj<"2
%?aS#4jI
/** 22vq=RO7Z
* @return Returns the totalPage. on50+)uN
* P`2&*2,
*/ FfXZ|o$;
publicint getTotalPage(){ #JS`e_3Rr
return totalPage;
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} 4<Kgmy
F@<MT<TRf
/** ,wTg$g-$
* @param totalPage B/_6Ieb+
* The totalPage to set. ,>w}xWSYpG
*/ pzSqbgfrQ
publicvoid setTotalPage(int totalPage){ + (=I8s/
this.totalPage = totalPage; ]wf|PU~nr
} u:5IjOb2^
$3:X+X
} \_>?V5(
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R-C5*$
,RN|d0dE
^H'kHl'F
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 MiD
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个PageUtil,负责对Page对象进行构造: 9fCO7AE0#
java代码: <?4cWp|i
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j J-d/"(
/*Created on 2005-4-14*/ V0T<e H<
package org.flyware.util.page; 9<Ag1l
D"`[6EN[
import org.apache.commons.logging.Log; NxB+?
import org.apache.commons.logging.LogFactory; vnVZJ}]w\
FK3Whe{KP{
/** \bRy(Z)
* @author Joa 2YluJ:LN
* %09*l%,;
*/ `{L{wJ:&a
publicclass PageUtil { Z fqQ{_
L6 kZ2-6
privatestaticfinal Log logger = LogFactory.getLog @ AggznA8
4L11P
(PageUtil.class); iP,v=pS6
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/** 8E
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* Use the origin page to create a new page ?"u'#f_
* @param page )O -cw7 >
* @param totalRecords 26}u4W$
* @return j $0zD:ppW
*/ j`hNZ %a
publicstatic Page createPage(Page page, int ? KF=W
;,v.(Z ic
totalRecords){ ^f6
{0
return createPage(page.getEveryPage(), <L2GUX36#
-O /T?H
page.getCurrentPage(), totalRecords); "W hwc
} ~R$[n.Vpk
XK3!V|y`
/** >*{:l,LH
* the basic page utils not including exception |yU3Kt
qkiJH T
handler k_BSY=$e*D
* @param everyPage 3Mxz_~
* @param currentPage q>P[n z%
* @param totalRecords S_j1=6#^
* @return page +`9yZOaC#
*/ >mew"0Q
publicstatic Page createPage(int everyPage, int i<bxc
r:.6"VQu}
currentPage, int totalRecords){ )FV6,
everyPage = getEveryPage(everyPage); 1O23"o5=
currentPage = getCurrentPage(currentPage); s9G)Bd 8
int beginIndex = getBeginIndex(everyPage, oFb\TiLu
&b!vWX1N
currentPage); L2<+#O#
int totalPage = getTotalPage(everyPage, Mc!2mE%47m
),MU+*`
totalRecords); QYH."7X
>
boolean hasNextPage = hasNextPage(currentPage, t z"5+uuu
(;C$gnr.C
totalPage); 2c"/QT
boolean hasPrePage = hasPrePage(currentPage); A0UV+ -PP
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returnnew Page(hasPrePage, hasNextPage, 8B_0!U&]
everyPage, totalPage, "wC0eDf
currentPage, XRtyC4f
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beginIndex); wG;}TxrLS
} :ao^/&HZ
219R&[cb
privatestaticint getEveryPage(int everyPage){ (I>HWRH
return everyPage == 0 ? 10 : everyPage; %-\FVKX
} Y'2-yB
F9F" F
privatestaticint getCurrentPage(int currentPage){ 3>H2xh 3Y
return currentPage == 0 ? 1 : currentPage; Tw}@+-
} j/~VP2R`
vNPfUEnA
privatestaticint getBeginIndex(int everyPage, int 4+-5,t7
vwm|I7/w
currentPage){ y9=t;qH@|
return(currentPage - 1) * everyPage; 8?A@/
} o@Scz!"g
U.Pa7tn
privatestaticint getTotalPage(int everyPage, int D xe-XKNc.
-|6V}wHg~
totalRecords){ KBd7|,j
int totalPage = 0; 0&.LBv8
zoR,RBU6
if(totalRecords % everyPage == 0) $xLEA\s
totalPage = totalRecords / everyPage; e',hC0&S
else F1 9;RaP+
totalPage = totalRecords / everyPage + 1 ; %uh R'8"
l}dj{s
return totalPage; A>4l/
} +GRxHuW,
K3a>^g
privatestaticboolean hasPrePage(int currentPage){ L-`(!j
return currentPage == 1 ? false : true; *Ro8W-+
} qw9e)
`3$
Gs^(YGtU
privatestaticboolean hasNextPage(int currentPage, N-]\oMc2
jQY>9+t
int totalPage){ -[G/2F'
return currentPage == totalPage || totalPage == [[#xES21F
GTT5<diw
0 ? false : true; m}; ~JMo]
} s.<olxXRW
I/u'bDq
#Y/97_2 xa
} 2qt=jz\s
qPp1:a"
0Ei\VVK>
LBW.*PHW
z~GVvgd
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。 e_YW~z=6t
]R97n|s_
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 ;+S2h-4
sZ0g99eX
做法如下: L+v8E/W
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 xmCm3ekmpC
$ iX^p4v
的信息,和一个结果集List: oc!biE`u
java代码: #N<s^KYG-
}T?i%l
~,(0h:8
/*Created on 2005-6-13*/ 113Z@F
package com.adt.bo; SIKk|I)
\DG(
8l
import java.util.List; Yt\E/*%
YR$tPe
import org.flyware.util.page.Page; .d<~a1k
wJ;9),fL
/** J`U$b+q6
* @author Joa 0S)"Q^6ny
*/ DR.3
J`?K
publicclass Result { nEjo,
.F{}~K]
private Page page; { Hktu|
a7QlU=\
private List content; eyI-s9#t
&xPOp$Sx~
/** `XQx$I
* The default constructor O[i2A(
*/ Y?"v2~;3
public Result(){ fY|@{]rx
super(); KUl
Zk^a
} , V0iMq
K8yWg\K
/** GV `idFd
* The constructor using fields &-EyM*:u!
* z{ Zimr
* @param page Qs#9X=6e@
* @param content ?M*C*/R
*/ 6/p]jN
public Result(Page page, List content){ &F@tmM~
this.page = page; '=@-aVp
this.content = content; _*OaiEL+:
} *@b~f&Lx6
hW*^1%1
/** 7v4-hfN
* @return Returns the content. Jgi{7J
*/ Z7K!"I
publicList getContent(){ ^*$WZMMJ1
return content; qiwQUm{
} 'ugR!o1
BP7<^`i&
/** yKX:Z4I/
* @return Returns the page. vZ1D3ytfG
*/ s5_1}KKCs
public Page getPage(){ W#oEF/G
return page; Q rrZF.
} >o=axZNa
g%<{G/Tz
/** <uWJ>sg^6
* @param content Gc3PN
* The content to set. P~b%;*m}8
*/ vl#V-UW$4P
public void setContent(List content){ 9fr&Yb=_o@
this.content = content; N@%xLJF=N>
} ^qSf
qB`0^V
/** (>)+;$Dr,\
* @param page %>x0*T$$
* The page to set. .q|xMS}4
*/ !T&u2=`D
publicvoid setPage(Page page){ _3FMQY(
this.page = page; A-@-?AR
} 6832N3=
} u:{.
Hn`
t`&s
.n^O)|Z
`gA5P %
R, (+NT$
2. 编写业务逻辑接口,并实现它(UserManager, ;r2b@x:<_
CM@"lV_
UserManagerImpl) 6P/9Vh j'
java代码: k^vmRe<lk
OM.(g%2
,rvZW}=
/*Created on 2005-7-15*/ MZhJ,km)
package com.adt.service; =^".{h'-
^HU=E@
import net.sf.hibernate.HibernateException; m-pIFL<^N
I{X@<o}
import org.flyware.util.page.Page; \C'I l
w
16d{IGMz
import com.adt.bo.Result; JqH.QnKcv
u0$5Fd&X
/** Hf E;$
* @author Joa ;*85'WcS
*/ im^I9G
publicinterface UserManager { 0 ^-b}
iaq:5||,
public Result listUser(Page page)throws Ug[F3J|Mu
p_kTLNZd9
HibernateException; 9BgQoK@
rqG6Ll`=+
} 7zOvoQ}
dsft=t8s
=}1~~
B1AF4}~5
`:^)"#z)
java代码: H"Em|LX^
:fMM-?s]
W0C$*oe!_i
/*Created on 2005-7-15*/ tI(t%~>^
package com.adt.service.impl; r%?}5"*
jl?y}
import java.util.List; =K&q;;h
&b#NF1Q.
import net.sf.hibernate.HibernateException; @rDv
(W
4h2bk\z-
import org.flyware.util.page.Page; sjgxx7
import org.flyware.util.page.PageUtil; Q0oDl8~
ZBh@%A
import com.adt.bo.Result; 'XjHB!!hU
import com.adt.dao.UserDAO; J1wGK|F~
import com.adt.exception.ObjectNotFoundException; %>QSeX
import com.adt.service.UserManager; )-7(Hv1
?(XX
/** UW~tS
* @author Joa JO;`Kz_$
*/ U1@P/
publicclass UserManagerImpl implements UserManager { d`rDEa
Vt 5XC~jK
private UserDAO userDAO; m:o$|7r
aG&kl O>m
/** Z_TbM^N
* @param userDAO The userDAO to set. @eD2<e
*/ W71#NjM2Z
publicvoid setUserDAO(UserDAO userDAO){ _a02#
this.userDAO = userDAO; "q#g/T
} yyYbB ]D
s</ktPtu
/* (non-Javadoc) iS^^Z ZyR
* @see com.adt.service.UserManager#listUser (5\d[||9g
Zi '8~iEH
(org.flyware.util.page.Page) P<w>1
=
*/ E9NGdp&-Ah
public Result listUser(Page page)throws mm~o%1|WR
t3kh]2t
HibernateException, ObjectNotFoundException { |x~ei_x7.p
int totalRecords = userDAO.getUserCount(); LB 5EGw
if(totalRecords == 0) UmHb-uk ;
throw new ObjectNotFoundException ny;)+v?mN\
;jfXU_K
("userNotExist"); oI"Fpo
page = PageUtil.createPage(page, totalRecords); SX<>6vH&
List users = userDAO.getUserByPage(page); N,'qMoNf
returnnew Result(page, users); (]uoN4
} ;{#M
/t2<OU9
} 4rCqN.J
qv >(
!!Gi.VL
vnT
G7#~=W
2M
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xn#I7]]G
-)c"cgx.
询,接下来编写UserDAO的代码: l<:)rg^,
3. UserDAO 和 UserDAOImpl: eFI9S.6
java代码: >WG91b<Xq
dJgOfg^
GAe_Z(T
/*Created on 2005-7-15*/ 4zvU"np
package com.adt.dao; F;l<>|vG
9n2%7dLQ*
import java.util.List; %.}
%1l80Z
import org.flyware.util.page.Page; st^N QL
UVi/Be#|
import net.sf.hibernate.HibernateException; )qQg n]
1+[|pXT}
/** 3B]+]e~
* @author Joa Bc`A]U
*/
WN?`Od:y
publicinterface UserDAO extends BaseDAO { fpC@3 itI
v8M#%QoA
publicList getUserByName(String name)throws m(Xr5hw:6
&_TjRj"
HibernateException; Q#AHEm{9;s
$XzlW=3y
publicint getUserCount()throws HibernateException; Qpu2RfP
{@`Uf;hPAX
publicList getUserByPage(Page page)throws =*G'.D /*
<{~UKi
HibernateException; ;&:Et
n/|`Dz.
} =Qq^=3@h
N`:bvr
`9NnL.w!
JHOBg{Wg
PW\FcT
java代码: V)?g4M3}
i(#c
Yb
rm;"98~zJ?
/*Created on 2005-7-15*/ , X+(wp
package com.adt.dao.impl; ed2&9E>9b
x@l~*6!K
import java.util.List; |Y8o+O_`
$CV'p/^En
import org.flyware.util.page.Page; V&nJT~k
HBYpjxh
import net.sf.hibernate.HibernateException; ho=]'MS|
import net.sf.hibernate.Query; {:j!@w 3
d|HM
import com.adt.dao.UserDAO; f@X*Tlx^|
eNskuG|1
/** Oc=PJf%D#
* @author Joa L*Cf&c`8r
*/ ^vz@d+\Kd
public class UserDAOImpl extends BaseDAOHibernateImpl \d`Sz
*
=1?yS3
implements UserDAO { '.v^seU
*g}&&$b0
/* (non-Javadoc) XsMphZnK
* @see com.adt.dao.UserDAO#getUserByName Lu5.$b
1F8EL)9
(java.lang.String) -w0>4JDs
*/ y`dzo`f
publicList getUserByName(String name)throws (NlEb'~+
[Y~ s
HibernateException { `a9>4
String querySentence = "FROM user in class U Bg_b?k
*a.*Ha
com.adt.po.User WHERE user.name=:name"; kV<)>Gs
Query query = getSession().createQuery )SLs
[
a
VMFjkW
(querySentence); \5_^P{p7<
query.setParameter("name", name); (LPc\\Vv
return query.list(); 4 (gf!U
} p-Btbhv
I(S6DkU
/* (non-Javadoc) N#ObxOE6T"
* @see com.adt.dao.UserDAO#getUserCount() \mGM#E
*/ Ji=iq=S7
publicint getUserCount()throws HibernateException { r $2
int count = 0; AXI:h"so
String querySentence = "SELECT count(*) FROM J8'zvH&I
m@?e
<$
user in class com.adt.po.User"; 1r4/McB
Query query = getSession().createQuery tYa*%|!v
I-hhHm<@
(querySentence); H|O}Dsj
count = ((Integer)query.iterate().next 5Yr$dNe
M] *pBc(o0
()).intValue(); GjG3aqP&!
return count; (o\~2e:
} )T_#X!
A4x3TW?
/* (non-Javadoc) )UUe5H6Hd0
* @see com.adt.dao.UserDAO#getUserByPage r/ f;\w7
z$b!J$A1
(org.flyware.util.page.Page) -/?<@*n
*/ '_Op rx
publicList getUserByPage(Page page)throws bq]a8tSB
{xH@8T$DX
HibernateException { RMXj)~4.
String querySentence = "FROM user in class b5R*]
Y6a|\K|
com.adt.po.User"; J_$~OEC~
Query query = getSession().createQuery bS<p dOX_
0rUf'S
?K
(querySentence); @9a=D<'>
query.setFirstResult(page.getBeginIndex()) s,x]zG"
.setMaxResults(page.getEveryPage()); eW%jDsC
return query.list(); RdHR[Usm
} `Mg
"!n`
eo[^ij
} 7m:, -xp
i/z7a%$
],|B4\b ;
^eii
4
A\Gw+l<h,
至此,一个完整的分页程序完成。前台的只需要调用 RwWQ$Eb_s
lla96\R
userManager.listUser(page)即可得到一个Page对象和结果集对象 "
cg>g/
<ZEA&:p
的综合体,而传入的参数page对象则可以由前台传入,如果用 AtI,&S#{
{VG6m
Hw
webwork,甚至可以直接在配置文件中指定。 %#~Wk|8} Q
,~#hHhR_
下面给出一个webwork调用示例: J)o%83//
java代码: ,?+yu6eLb
`R RORzXoS
P9vROzXK
/*Created on 2005-6-17*/ [G*mQ@G9
package com.adt.action.user; ;U&VPIX$
rv:O|wZ
import java.util.List; "5K:"m
bv "S(
import org.apache.commons.logging.Log; DP_ \%(A
import org.apache.commons.logging.LogFactory; jYv
!}
import org.flyware.util.page.Page; vCM'nkXY
1YxI q565
import com.adt.bo.Result; 3$54*J
import com.adt.service.UserService; dQ]j
r.
import com.opensymphony.xwork.Action;
q-#fuD^
p(Mv^ea
/** ;f
Gi5=-
* @author Joa 4tjRju?
*/ ojri~erJE?
publicclass ListUser implementsAction{ lRb)Tz6SE
|a+8-@-Tj
privatestaticfinal Log logger = LogFactory.getLog 2 6A#X
R#>E{[9
(ListUser.class); "5Mo%cUp
z~qQ@u|
private UserService userService; Qw:j2g2H7
KMV!Hqkk
private Page page; O9Aooe4W=
\=)h6AG
privateList users; r+Y1m\
uY,FugWbl
/* x/~M=][tN
* (non-Javadoc) 3-'|hb
* gK /K Z8
* @see com.opensymphony.xwork.Action#execute() 4)_ [)MZ\j
*/ OuoZd!"qf
publicString execute()throwsException{ $)3/N&GXR
Result result = userService.listUser(page); {+;8dtZ)x
page = result.getPage(); l}x{.q7Ul
users = result.getContent(); tR3hbL$W
return SUCCESS; a$
}^z
} UWHC]V?
Hg4Ut/0
/** <Vim\
* @return Returns the page. ]+AI:
*/ $1e@3mzM
public Page getPage(){ H\T
h4teE
return page; `8I&(k<wLe
} @OpcS>:R
;
OsN^
/** s=:n<`Z2
* @return Returns the users. S<TfvQ\,"@
*/ 4?Io@[7A)
publicList getUsers(){ (&S v$L@
return users; I ;_.tG
} Nn$$yUkMX
08Q:1 '
/** f]Vz !hM~
* @param page N|DY)W
* The page to set. x{rt\OT
*/ .#X0P=
publicvoid setPage(Page page){ <YC{q>EMc
this.page = page;
[7bY(
} W6pS.}
jV(ISD
/** B~^\jRd"
* @param users ^JTfRZ:a
* The users to set. ?@~FT1"6G
*/ f*Kipgp
publicvoid setUsers(List users){ {1o=/&
this.users = users; }V 1sY^C
} U5Y*xm<
@:Ns`+ W*
/** Th8xh=F[
* @param userService ;RU)Q)a)
* The userService to set. _Qv4;a
*/ )YZ41K5N
publicvoid setUserService(UserService userService){ _u>+H#
this.userService = userService; 8)i\d`
} !MbRI
} $z<CkMP!U7
og>f1NwS[
bHp|>g
!n7?w@2a'
5+U~ZW0|+
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, I0Vm^\8
:7R\"@V4
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 sIyLW
U}UIbJD*=
么只需要: ? f%@8%px
java代码: (k[<>$hL*
3}"VUS0wh
<Sz9: hg-
<?xml version="1.0"?> Ss8`;>
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork A3Su&0uaB
9(m^^
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &?~> I[^~
-/h$Yb
1.0.dtd"> , 7}Ri
4F'@yi^Gt
<xwork> >6@UjGj54
b&LhydaJ
<package name="user" extends="webwork- ;G w5gK^
YXmLd'F^3
interceptors"> f`?|A
U8moVj8w1
<!-- The default interceptor stack name `aCcTs7~]p
Q[}mH: w
--> UPbG_ #"wZ
<default-interceptor-ref 2+|[e_
6ds&n#n
name="myDefaultWebStack"/> V482V#BP
jildiT[s
<action name="listUser" +ux,cx.U"
(j2]:BVu
class="com.adt.action.user.ListUser"> z8gp<5=
<param n.XT-X^
towQoqv
name="page.everyPage">10</param> f5'+F-`N
<result #*~#t4S-
^D!UF(H
name="success">/user/user_list.jsp</result> -1fT2e
</action> \;Ii(3+v;
J&lQ,T!?B
</package> r=s7be
yM>c**9
</xwork> r|
YuHm
Zu5`-[mw
Lw3Z^G
3uN;*f
CA{c-kG
T,k`WR
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 q'PA2a:
w@hm>6j
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 La9dFe-uu{
H=B8'N
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 X.g1
312~
0'a.Ypf
<x,$ODso
{"O'kx
si)920?E&
我写的一个用于分页的类,用了泛型了,hoho '#^ONn STn
~]}7|VN.}
java代码: PE3l2kr
mhh8<BI
92XzbbLp
package com.intokr.util; iQ:]1H s
f\1)BZ'I
import java.util.List; nd-y`@z
%|4Nmf$:Og
/** ?FD^S~bz-
* 用于分页的类<br> ]Rz]"JZ\S
* 可以用于传递查询的结果也可以用于传送查询的参数<br> $dq
R]'
* e3&R3{
* @version 0.01 {5:y,=Y
* @author cheng Qb/qUUQO;0
*/ FhW\23OC
public class Paginator<E> { |]^OX$d
privateint count = 0; // 总记录数 4h?[NOA"
privateint p = 1; // 页编号 9=Y-w s
privateint num = 20; // 每页的记录数 EZao\,t
privateList<E> results = null; // 结果 .#P'NF(5#
*uNa(yd
/** S$ dFz
* 结果总数 W$
M4#
*/ #\Lt0
publicint getCount(){ 2B5Z0<
return count; m%l\EE
} ,{7Z OzA
8h}o5B
publicvoid setCount(int count){ | M4_@P
this.count = count; 9>%ti&_-jt
} GVe[)R
Beqzw0
/** G-xW&wC-
* 本结果所在的页码,从1开始 F:1w%#6av
* Js ~_8
* @return Returns the pageNo. qf7lQovK
*/ o{lR_
publicint getP(){ BH0].-)[y!
return p; YR^J7b\
} ma,H<0R
;5?$q
/** hxGZ}zq*S
* if(p<=0) p=1 6j+_)7.V
* #zyEN+
* @param p FTsvPLIv"
*/ txw:m*(%
publicvoid setP(int p){ 4DaLmQ2O
if(p <= 0) 'WUd7
p = 1; Q!iM7C!8
this.p = p; iG^o@*}a
} O'*KNJX
e3}`]
/** qlNK }
* 每页记录数量 2r]80sWY
*/ l`M{Ravvn*
publicint getNum(){ Cj#$WZga%
return num; |gg6|,Bt4
} tI ~.3+F
3o5aB1
/** CI{? Kb
* if(num<1) num=1 mfc\w'
*/ pa*bqPi
publicvoid setNum(int num){ 3dTz$s/[
if(num < 1) 8m\*~IX=
num = 1; gi#bU
this.num = num; +`>Tuz~
} ~7IXJeon
"AMbU68
/** _o`+c wc
* 获得总页数 ?A+-k4l
*/ yY_Zq\
publicint getPageNum(){ Btp 9v<"
return(count - 1) / num + 1; JTA65T{3
} .zZee,kM
9`4M o+
/** U@T"teGBA
* 获得本页的开始编号,为 (p-1)*num+1 i=jwk_y
*/ | vL0}e
publicint getStart(){ pyJY]"UHVE
return(p - 1) * num + 1; E<]O,z;F
} agp`<1h9
GH[ATL
/** xkV(E!O
* @return Returns the results. sxkWg>
*/ ?Dm={S6
publicList<E> getResults(){ 4+I @
return results; ammlUWl
} '_oWpzpe
%? -E)n[
public void setResults(List<E> results){ 0h=NbLr|S-
this.results = results; 0}H7Xdkp
} c&me=WD
z-ns@y(f@X
public String toString(){ &m[ZpJ9
StringBuilder buff = new StringBuilder ?gD^K,A Hd
c_wvuKa
(); o{MF'B#
buff.append("{"); 0P i+ (X
buff.append("count:").append(count); [}:;B$,
buff.append(",p:").append(p); pZHx
buff.append(",nump:").append(num); >J(._K
buff.append(",results:").append ?i'N9 /(
F#NuZ'U
(results); t$~CLq5ad
buff.append("}"); NhJ]X cfP8
return buff.toString(); rMr:\M]t
} j}u b
rZ`+g7&^Fh
} ,Y9bXC8+dU
~P!\;S
w]1hoYuV