Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 u:2Ll[ eo
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 m,!SDCq
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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 la_c:#ho
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分页支持类: O0xqA\
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java代码: L/exR6M7
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package com.javaeye.common.util; iW>^'W#
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import java.util.List; cPNc$^Y
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publicclass PaginationSupport { bIyg7X)/
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publicfinalstaticint PAGESIZE = 30; qx[c0X!
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privateint pageSize = PAGESIZE; >>$`]]7
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privateList items; pC>h"Hy
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privateint totalCount; N\ !
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privateint[] indexes = newint[0]; y7fy9jQ
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privateint startIndex = 0; 3S7"P$q
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public PaginationSupport(List items, int aYb97}kI
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totalCount){ G_S>{<[
setPageSize(PAGESIZE); n@p@@
setTotalCount(totalCount); E6 -*2U)k+
setItems(items); ^.!jD+=I
setStartIndex(0); </`\3t
} >- \bLr
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public PaginationSupport(List items, int q_h (D/g
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totalCount, int startIndex){ uwSSrT
setPageSize(PAGESIZE); 5MAfuHq^
setTotalCount(totalCount); fyb;*hgu
setItems(items); =#S.t:HQ*
setStartIndex(startIndex); KaNs>[a8
} aY>v
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public PaginationSupport(List items, int zR^Gy"
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totalCount, int pageSize, int startIndex){ bH e'
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setPageSize(pageSize); @I`^\oJ
setTotalCount(totalCount); S-7&$n
setItems(items); - |g"q|
setStartIndex(startIndex); ^U*y*l$
} *(F`NJ 3
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publicList getItems(){ *7jz(iX
return items; akzGJ3g
} Z,.Hz\y1D
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publicvoid setItems(List items){ [7FG;}lB-
this.items = items; F^75y?
} c>B1cR
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publicint getPageSize(){ "0P`=n
return pageSize; t~->&Ja
} -Lh7!d
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publicvoid setPageSize(int pageSize){ >CqzC8JF
this.pageSize = pageSize; ##7y|AwK
} 6:7[>|okQ
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publicint getTotalCount(){ _F;v3|`D@<
return totalCount; k2U*dn"9U
} l<`>
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publicvoid setTotalCount(int totalCount){ lT^su'+bk
if(totalCount > 0){ "]+g5G
this.totalCount = totalCount; YA4 D?'
int count = totalCount / j<B9$8x&
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pageSize; f~`=I NrU
if(totalCount % pageSize > 0) j~Aq-8R=
count++; !*N9PUM
indexes = newint[count]; @%]A,\
for(int i = 0; i < count; i++){ Qd[_W^QI
indexes = pageSize * 2*|T)OA`m,
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} h Jb2y`,q
}else{ [0 F~e
this.totalCount = 0; b dgkA
} *;Jb=
} D@O`"2
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publicint[] getIndexes(){ -K64J5|b7
return indexes; ,&P
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} z0[XI 7KK
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publicvoid setIndexes(int[] indexes){ 4l$OO;B
this.indexes = indexes; i+Z)`
} s,HbW%s
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publicint getStartIndex(){ B>,eHXW
return startIndex; vrnvv?HPrR
} ^3;B4tj[
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publicvoid setStartIndex(int startIndex){ &9L4
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if(totalCount <= 0) x< A-Ws{^V
this.startIndex = 0; u_(~zs.N]
elseif(startIndex >= totalCount) *]$B 9zVs!
this.startIndex = indexes ".?4`@7F\
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[indexes.length - 1]; SH%NYjj
elseif(startIndex < 0) z
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this.startIndex = 0; H+v&4} f
else{ 77P\:xc
this.startIndex = indexes IPQRdBQ
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[startIndex / pageSize]; 6 d-\+t8
} *_(X$qfoW
} nBh+UT}
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publicint getNextIndex(){ #[+# bw_6
int nextIndex = getStartIndex() + $R9D
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pageSize; po| Ux`u
if(nextIndex >= totalCount) OM86C
return getStartIndex(); #@R0$x
else l A ^1}
return nextIndex; Br1R++]
} %B s. XW,
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publicint getPreviousIndex(){ C/kf?:j
int previousIndex = getStartIndex() - Pvxb6\G&d
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pageSize; VD;*UkapZx
if(previousIndex < 0) slQn
return0; ~k"+5bHa*
else VY?9|};f
return previousIndex; #}`sfaT
} HW@wia
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} "+HJ/8Dd1
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抽象业务类 ;Qi:j^+P)
java代码: 6u[fCGi%
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/** 7=^{~5#
* Created on 2005-7-12 8Fn\ycX#"l
*/ /*0t_
package com.javaeye.common.business; ]aX@(3G1s
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import java.io.Serializable; _imuyt".+
import java.util.List; <c+.%ka
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import org.hibernate.Criteria; #;[G>-tC
import org.hibernate.HibernateException; i]8O?Ab>?
import org.hibernate.Session; Pv -4psdw
import org.hibernate.criterion.DetachedCriteria; W06aj ~7Z
import org.hibernate.criterion.Projections; HsY5wC
import fY<#KM6X
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org.springframework.orm.hibernate3.HibernateCallback; 5pQpzn=
import a4Q@sn;]
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org.springframework.orm.hibernate3.support.HibernateDaoS GZ%vFje_
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upport; T{dQ4
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import com.javaeye.common.util.PaginationSupport; \}Q=q$)
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public abstract class AbstractManager extends %>Kba M1b
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HibernateDaoSupport { HNzxFnh
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privateboolean cacheQueries = false; 0eY!Z._^
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privateString queryCacheRegion; (7 I|lf
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publicvoid setCacheQueries(boolean ?sN{U\
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cacheQueries){ zPt<b!q
this.cacheQueries = cacheQueries; &Ok1j0~~
} Yy *=@qu>g
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publicvoid setQueryCacheRegion(String mixsJ}e
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queryCacheRegion){ EU[\D;
this.queryCacheRegion = "O34 E?ql.
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queryCacheRegion; u\\t~<8
} ;aQ``B
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publicvoid save(finalObject entity){ =AIts[!qd
getHibernateTemplate().save(entity); P6+ B!pY
} 3h7RQ:lUi
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publicvoid persist(finalObject entity){ CG1MT(V7?
getHibernateTemplate().save(entity); 1wFu3fh@
} C;W@OS-;
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publicvoid update(finalObject entity){ z; GQnAG@
getHibernateTemplate().update(entity); 8(1*,CJQg
} * %D_\0;
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publicvoid delete(finalObject entity){ nPyn~3
getHibernateTemplate().delete(entity); mnm
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} juF9:Eah
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publicObject load(finalClass entity, J!:BCjRdw
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finalSerializable id){ 64B.7S88
return getHibernateTemplate().load 2Q6;SF"Z
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(entity, id); pGs?Y81
} uu6 JZp
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publicObject get(finalClass entity, t^01@ejM+
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finalSerializable id){ ?+zFa2J
return getHibernateTemplate().get +|/0sPW(
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(entity, id); ;,77|]<XE
} Ark]>4x>
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publicList findAll(finalClass entity){ {H)7K.hQN
return getHibernateTemplate().find("from OAXA<
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" + entity.getName()); $;^|]/-
} "xlR>M6e
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publicList findByNamedQuery(finalString ZiPeP
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namedQuery){ \Oq2{Sx\
return getHibernateTemplate D!.c??
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().findByNamedQuery(namedQuery); in>+D|q
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} 3Q,&D'];[
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publicList findByNamedQuery(finalString query, U'=8:&
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finalObject parameter){ 'V]C.`9c
return getHibernateTemplate C3'xU` =7
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().findByNamedQuery(query, parameter); ny
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} r^m&<)Ca
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publicList findByNamedQuery(finalString query, gvI!Ice#
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finalObject[] parameters){ I8XP`Ccq
return getHibernateTemplate k2
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().findByNamedQuery(query, parameters); s4fO4.bn m
} 4EM+ Ye
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publicList find(finalString query){
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return getHibernateTemplate().find ].Yz
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(query); P2vG)u
} ;t0q
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publicList find(finalString query, finalObject e,|gr"$/
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parameter){ 'LMj.#A<g
return getHibernateTemplate().find y'm!h?8
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(query, parameter); Z"VP<-
} pVc+}Wzh
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public PaginationSupport findPageByCriteria e*Wk;D&
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(final DetachedCriteria detachedCriteria){ =!t;e~^8]
return findPageByCriteria Xqw}O2QQ1
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 1_t+lJI9j
} Ry>y
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public PaginationSupport findPageByCriteria 6FzB-],
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(final DetachedCriteria detachedCriteria, finalint m%6VwV7U
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startIndex){ E!ndXz 59
return findPageByCriteria HF0G=U}i
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(detachedCriteria, PaginationSupport.PAGESIZE, TR3U<:
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startIndex); R ABw(b
} "r46Rfa
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public PaginationSupport findPageByCriteria HaVhdv3L
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(final DetachedCriteria detachedCriteria, finalint }`gOfj)?i
by<@\n2B:U
pageSize, y.lWyH9
finalint startIndex){ lQ?jdi
return(PaginationSupport) "jAd.x?X7e
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getHibernateTemplate().execute(new HibernateCallback(){ ,jRAVt+{N
publicObject doInHibernate %_W4\
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(Session session)throws HibernateException { -8^qtB
Criteria criteria = p?f\/
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detachedCriteria.getExecutableCriteria(session); Y5tyFi#w[
int totalCount = '$OUe {j<
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((Integer) criteria.setProjection(Projections.rowCount At\(/Zy
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()).uniqueResult()).intValue(); l\W|a'i
criteria.setProjection xuvW6Q;
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(null); O?X[&t
List items = @#4-4.6I<x
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criteria.setFirstResult(startIndex).setMaxResults ??"_o3
i3,.E]/wX@
(pageSize).list(); tq59w
PaginationSupport ps = 0cycnOd
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new PaginationSupport(items, totalCount, pageSize, \Sd8PGl*'
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startIndex); 6|NH*#s
return ps; _P.I+!w:x
} 2#7|zhgb
}, true); :$"{-n
} Q7uJ9Y{X
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public List findAllByCriteria(final /i"hViCrlG
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DetachedCriteria detachedCriteria){ dQ8RrD=$&
return(List) getHibernateTemplate [1vm~w'
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().execute(new HibernateCallback(){ 6axxyh%
publicObject doInHibernate FY'0?CT$
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#
(Session session)throws HibernateException { (%fQhQ
Criteria criteria = w||t3!M+n
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detachedCriteria.getExecutableCriteria(session); t.ulG
*
return criteria.list(); Rv&"h_"t
} <uuumi-!%G
}, true); bX$z)]KKu
} 6RbDc*
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public int getCountByCriteria(final WkuCnT
@SD XJJh
DetachedCriteria detachedCriteria){ 3 ZOD2:(
Integer count = (Integer) %<>:$4U@]
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getHibernateTemplate().execute(new HibernateCallback(){ tKt}]KHV
publicObject doInHibernate i?/Q7D<P
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(Session session)throws HibernateException { 1x_EAHZ>7
Criteria criteria = MZ"V\6T]
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detachedCriteria.getExecutableCriteria(session); 3?B1oIHQ
return [k$GUU,jY
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criteria.setProjection(Projections.rowCount sc]#T)xG
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()).uniqueResult(); :z8/iD y
} ;((t|
}, true);
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return count.intValue(); 8~(,qU8- N
} (n k g
} +1wEoU.l2
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用户在web层构造查询条件detachedCriteria,和可选的 ]lA}5
}`L;.9
startIndex,调用业务bean的相应findByCriteria方法,返回一个 MX]#|hEeQ
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PaginationSupport的实例ps。 Oey
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ps.getItems()得到已分页好的结果集 -F/)-s6#!'
ps.getIndexes()得到分页索引的数组 Ei:m@}g
ps.getTotalCount()得到总结果数 p8 S~`fjV
ps.getStartIndex()当前分页索引 #Tc`W_-
ps.getNextIndex()下一页索引 dXDyY
ps.getPreviousIndex()上一页索引 OD}Uc+;K
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 cl`kd)"v
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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 JVg}XwR
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一下代码重构了。 Fdl0V:<
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我把原本我的做法也提供出来供大家讨论吧: b6;MTz*k>
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首先,为了实现分页查询,我封装了一个Page类: B0RVtbK
java代码: MA{ZmPm)
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/*Created on 2005-4-14*/ [GCaRk>b,
package org.flyware.util.page; t(UBs-t
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/** M.SF}U
* @author Joa xTG5VBv
* ;]R5:LbXS
*/ CNV^,`FX
publicclass Page { d?5oJ'JU
xGOmvn^lQ
/** imply if the page has previous page */ YpZuAJm<2_
privateboolean hasPrePage;
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/** imply if the page has next page */ ,W'P8C
privateboolean hasNextPage; Q-iBK*-w
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/** the number of every page */ ?w'03lr%
privateint everyPage; &n?RKcH}d
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/** the total page number */ I=Y_EjZD
privateint totalPage; ^Et^,I:`
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/** the number of current page */ Kl ?C[
privateint currentPage; 6[FXgCb
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/** the begin index of the records by the current %IIFLlD
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query */ K{Nj-Rqd
privateint beginIndex; Qo]qs+
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/** The default constructor */ )yz)Fw|&
public Page(){ wKpD++k
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} Jz0AYiCq
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/** construct the page by everyPage i$.! 8AV6
* @param everyPage hZ|0<u
* */ ^VnnYtCRz
public Page(int everyPage){ 0e:j=kd)NH
this.everyPage = everyPage; J`; 9Z
} Te3 ?z
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/** The whole constructor */ H:Q4!<
public Page(boolean hasPrePage, boolean hasNextPage, sA+K?_
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int everyPage, int totalPage, L6jwJwD
int currentPage, int beginIndex){ ww+,GnV
this.hasPrePage = hasPrePage; I4<_y5
this.hasNextPage = hasNextPage; ym` 4v5w
this.everyPage = everyPage; 6B
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this.totalPage = totalPage; -) +B!"1
this.currentPage = currentPage; T'Jl,)"
this.beginIndex = beginIndex; xMpgXB!'
} [1Qg *
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/** D)[(
* @return ^%\MOjSN
* Returns the beginIndex. ^@Qc!(P
*/ 2PNe~9)*#
publicint getBeginIndex(){ LOwd mj
return beginIndex; ^FTS'/Q
} ts,V+cEA
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/** fCX8s(|F
* @param beginIndex 4T~wnTH0Xg
* The beginIndex to set. puh-\Q/P
*/ M D&7k,!
publicvoid setBeginIndex(int beginIndex){ <a+@4d;
this.beginIndex = beginIndex; W]>%*n
} s._,IW;
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/** YPKB4p#
* @return vr6YE;Rs
* Returns the currentPage. G2sj<F=AV
*/ /*"pylm
publicint getCurrentPage(){ Vkf{dHjW
return currentPage; I;UT;/E2
} 7^d7:1M
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/** }{&;\^i
* @param currentPage v5{2hCdt
* The currentPage to set. nuA
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*/ .F$cR^i5u
publicvoid setCurrentPage(int currentPage){ Czy}~;_Ay
this.currentPage = currentPage; Y%}N@ ,lT
} I;G(Wj
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/** 'C>sYSL
* @return bu08`P9
* Returns the everyPage. _lm^v%J$
*/ )$d~HA@B
publicint getEveryPage(){ =NNxe"Kd;U
return everyPage; h7o.RRhK
} *=T(ncR['
nC!L<OMr
/** !?|xeQ}
* @param everyPage 8 tIy"5
* The everyPage to set. @:>gRD
*/ 6V#EEb
publicvoid setEveryPage(int everyPage){ OF-VVIS
this.everyPage = everyPage; _qo\E=E
} B`jq"[w]-
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/** &H+n0v
* @return Imq-5To#
* Returns the hasNextPage. "I9 r>=
*/ $3%+N|L
publicboolean getHasNextPage(){ 8yH)9#>
return hasNextPage; | :id/
} IcGX~zWr
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/** wTG(U3{3K
* @param hasNextPage %hdjQIH
* The hasNextPage to set. 'G>9 iw
*/ ooC9a>X
publicvoid setHasNextPage(boolean hasNextPage){ m^,VEV>
this.hasNextPage = hasNextPage; (Q8r2*L
} 8lA,3'z
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/** :fq4oHA#
* @return |k,-]c;6
* Returns the hasPrePage. M.:JT31>1
*/ {];-b0MS~
publicboolean getHasPrePage(){ _aJKt3GQ
return hasPrePage; :F@goiuC
} uU^iY$w
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/** {Qn{w%!|
* @param hasPrePage L'
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* The hasPrePage to set. Ndgx@LTQQ
*/ ^5(d^N
publicvoid setHasPrePage(boolean hasPrePage){ 0r8Wv,7Bo
this.hasPrePage = hasPrePage; 49c-`[d
L
} WIpV'F|t]`
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/** DH.UJ+
* @return Returns the totalPage. ItZYOt|Hn
* jIVD i~Ld
*/ I3d}DpPx%
publicint getTotalPage(){ '
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return totalPage; ;[(d=6{hc]
} 6 . )Xeb"
dM P'Vnfj
/** B&0W P5OF
* @param totalPage ^w2 HF
* The totalPage to set. cO5zg<wF
*/ ;gD\JA
publicvoid setTotalPage(int totalPage){ zNdkwj p+
this.totalPage = totalPage; 4v3gpLH
} v\@RwtP
{*[(j^OE
} Zj'%c2U_
o)^Wz
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NY.* S6
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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 0 yq
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个PageUtil,负责对Page对象进行构造: zB~< @
java代码: J p+'"a
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/*Created on 2005-4-14*/ ^2+Vt=*
package org.flyware.util.page; Fb=uN
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import org.apache.commons.logging.Log; M*kE |q/K
import org.apache.commons.logging.LogFactory; $Th)z}A}EA
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/** [|=M<>?[
* @author Joa VJ&<6
* J'$NBws
*/ *Q/^ib9=
publicclass PageUtil { #S'uqP!
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privatestaticfinal Log logger = LogFactory.getLog /bB4ec8!
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(PageUtil.class); >(S)aug$1
H>+])~#
/** Q47R`"
* Use the origin page to create a new page Opc szq5n
* @param page 7Y(Dg`8G
* @param totalRecords hRu}P"
* @return W/>a 1
*/ to</
publicstatic Page createPage(Page page, int "g&f:[a/
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totalRecords){ ?{J1Uw<
return createPage(page.getEveryPage(), &um++
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page.getCurrentPage(), totalRecords); !ZH "$m|
} TZt;-t`
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/** $jE<n/8
* the basic page utils not including exception BoYY^ih
8xgBNQdPT
handler \]]K{DO
* @param everyPage ^]R_t@
* @param currentPage B?=R= p
* @param totalRecords 9U6$-]J
* @return page !6=;dX
*/ /-[vC$B"
publicstatic Page createPage(int everyPage, int uhfK\.3
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currentPage, int totalRecords){ K}re{y
everyPage = getEveryPage(everyPage); BNCM{}e
currentPage = getCurrentPage(currentPage); oOpEpQ}}q
int beginIndex = getBeginIndex(everyPage, K?'m#}]
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currentPage); ]?@ [Ny=0
int totalPage = getTotalPage(everyPage, V=8db%^
~
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totalRecords); %"Um8`]FVg
boolean hasNextPage = hasNextPage(currentPage, g]?pY
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totalPage); k4LrUd
boolean hasPrePage = hasPrePage(currentPage); t;w<n"
6)uBUM;i
returnnew Page(hasPrePage, hasNextPage, |> STb\
everyPage, totalPage, 2{b/*w
currentPage, yO%^[c?
%"mI["{
beginIndex); )
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} zU&Iy_Ke.
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privatestaticint getEveryPage(int everyPage){ J\*uW|=F
return everyPage == 0 ? 10 : everyPage;
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} Ip{R'HG/
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privatestaticint getCurrentPage(int currentPage){ TS6xF?
return currentPage == 0 ? 1 : currentPage; DfAF-Yhut
} ZDmL?mC
"D.<~!
privatestaticint getBeginIndex(int everyPage, int }[JB%
zBy} > Jx
currentPage){ j_so s%-
return(currentPage - 1) * everyPage; #G]IEO$M6
} C;m"W5+
d9S/_iCI
privatestaticint getTotalPage(int everyPage, int 68u?}8}
]?VVwft
totalRecords){ 2(DhKHrF
int totalPage = 0; b=lJ`|
.ifz9jM'
if(totalRecords % everyPage == 0) Uyb0iQ-,s
totalPage = totalRecords / everyPage; p\=T#lb
else yk4@@kHW
totalPage = totalRecords / everyPage + 1 ; >1!u]R<3
PSq?8.
return totalPage; 8S8qj"s
} L/:l>Ko>7
Q ")Xg:
privatestaticboolean hasPrePage(int currentPage){ B.G6vx4yp
return currentPage == 1 ? false : true; 4aOz=/x2
} D{B?2}X
\"ahs7ABT
privatestaticboolean hasNextPage(int currentPage, Bz } nP9
nvrh7l9nX
int totalPage){ M5WB.L[@q
return currentPage == totalPage || totalPage == 0V<kpC,4
LH4#p%Pb%
0 ? false : true; e&
`"}^X;I
} %.=}v7&<z
e}?Q&Lci
]F+|C
} j<kW+Iio
$}su'EIo
htbE
Q NW
,7@\e&/&
]YI9
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 [>v1JN
CPy>sV3Ru0
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 1=J& ^O{W
&YY`XEG59O
做法如下: 4:rwzRDY
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 5{b;wLi$X2
14'\@xJMM
的信息,和一个结果集List: r&8aB85
java代码: ZJ%NZAxy
cS%dTrfo
'EIe5Op
/*Created on 2005-6-13*/ 4\-11!'08
package com.adt.bo; ]#G s6CsT|
_R ]s1
import java.util.List; 5 I_ :7$8
Dazm8_x
import org.flyware.util.page.Page; K^<?LXJF
Chnt)N`/B4
/** 129\H<
m
* @author Joa dGk"`/@
*/ Rr
[_t FM
publicclass Result { :7 LA/j
BO*)cLQ
private Page page; EY"of[p
V$hL\`e
private List content; `W1uU=c
;wMu
/** |1_$\k9Y&
* The default constructor t,De/ L
*/ |*t 2IVwX
public Result(){ r2#G|/=@
super(); w =F9>
} >;9g`d
_fk}d[q0
/** @@*x/"GJG
* The constructor using fields Fb1<Ic#
* X[.%[G|oj}
* @param page b/[X8w'VP
* @param content a%c <3'
*/ +#wVe
public Result(Page page, List content){ M <JX
this.page = page; 3\RD%[}
this.content = content; r4P%.YO+X
} kkZ}&OXS;
b * \
oQ
/** YZfi-35@g
* @return Returns the content. O$,
*/ jo&j<3i
publicList getContent(){ 6rbR0dSgx
return content; bp'%UgA)1
} dCM&Yf}K
%iNgHoH
/** N<SW
$ o
* @return Returns the page. qnyacI
*/ {f/]K GGk
public Page getPage(){ awR !=\
return page; M{orw;1Isy
} 8!35
K
JZ`u?ZaJ/s
/** ZFMO;'m&
* @param content 9j^rFG!n
* The content to set. e~gNGr]L/
*/ b0'}BMJ
public void setContent(List content){
)0E_Y@
this.content = content; X,+a 6F
} }.D18bE(
=U~53Tg
/** -flcB|I`
* @param page &;?+ ^L>
* The page to set. *\#<2 QAe
*/ >!Y#2]@}o
publicvoid setPage(Page page){ VXZYRr3F
this.page = page; bn|HvLQ"1
} pvl];w
} 6@lZVM)E
+cXi|Zf
-ewR:Y@j
T]Q4=xsv
XBX`L"0
2. 编写业务逻辑接口,并实现它(UserManager,
TR*vZzoy
:55a9d1bL
UserManagerImpl) !oi
{8X@
java代码: wKdWE`|y
bbS,pid1
;=@O.iF;H
/*Created on 2005-7-15*/ AW\uE[kg
package com.adt.service; xX<T5Ls
;uc3_J]
import net.sf.hibernate.HibernateException; 4 5wqX h
dm"x?[2:
import org.flyware.util.page.Page; fup?Mg-
/m>SEo\{C
import com.adt.bo.Result; qYVeFSS
^GYVRD
/** (bsywM
* @author Joa ;2`t0#J$]
*/ 2N |iOog
publicinterface UserManager { {4SaSv^/
2h<_?GM\s
public Result listUser(Page page)throws qp*~|
9MJ:]F5+
HibernateException; @6|0H`kv
6)=;cc{Vr
} /g%RIzgW
"+ {2!
e\aW~zs 2
_qOynW
CD#U`jf
java代码: ^wSGrV'
oPBKPGD
v5 p`=Z@%
/*Created on 2005-7-15*/ w(S&X"~
package com.adt.service.impl; FmF[S&gFRs
QTF1~A\
import java.util.List; k[ pk R{e
u f<%!=e
import net.sf.hibernate.HibernateException; (I;81h`1G
h)W#
import org.flyware.util.page.Page; &\5bo=5V
import org.flyware.util.page.PageUtil; txMC^-J2l
YsiH=x
import com.adt.bo.Result; J^DyhCs
import com.adt.dao.UserDAO; <jFov`^
import com.adt.exception.ObjectNotFoundException; fpZHE=}r
import com.adt.service.UserManager; MVQ6I/EA4
w .M
/** 1S+T:n
* @author Joa `z/p,. u
*/ 6v}q @z
publicclass UserManagerImpl implements UserManager { o9Mr7
d7&d
FvG
private UserDAO userDAO;
{fEb>
x}`)'a[
/** |z@AvS[
* @param userDAO The userDAO to set. k $ SMQ6
*/ }a UQ#x
publicvoid setUserDAO(UserDAO userDAO){ >x~Qa@s;
this.userDAO = userDAO; |Q%nnN
} #{k+^7aQ
KG(l=? N
/* (non-Javadoc) !xg10N}I
* @see com.adt.service.UserManager#listUser -
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nD
4C $
(org.flyware.util.page.Page) OYa9f[ $
*/ e !w{ap8u
public Result listUser(Page page)throws K-c>J
uv&,
hDoFF8)c
HibernateException, ObjectNotFoundException { Y@Ry
oJ
int totalRecords = userDAO.getUserCount(); c&<Ei1
if(totalRecords == 0) Gp?pSI,b.t
throw new ObjectNotFoundException 'c/8|9jX
6 RSit
("userNotExist"); dgByl-8Q
page = PageUtil.createPage(page, totalRecords); NP!LBB)=Y
List users = userDAO.getUserByPage(page); ?d3<GhzlR3
returnnew Result(page, users); i_!$bk<yo
} Nd;pkssd
cnY}^_
} (v0Q.Q@<
5VVU%STP
u<Ch]m+
{8;}y[R
N
/;Vg^Wx
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 GbkDs-
11 A$#\,
询,接下来编写UserDAO的代码: h]Gvt 5
3. UserDAO 和 UserDAOImpl: (enOj0
java代码: $(yi+v
J'&K
NUtKT~V
/*Created on 2005-7-15*/ t`eIkq|NxI
package com.adt.dao; %_39Wa
r'*#i>PkQD
import java.util.List; M,r8 No
).tTDZ
import org.flyware.util.page.Page; Cs vwc%
p7.~k1h
import net.sf.hibernate.HibernateException; OSh'b$Z
fQw=z$
/** <)L[V
* @author Joa eQfXUpk3@I
*/ 6OtNWbB
publicinterface UserDAO extends BaseDAO { dD
6jMl
QZL,zI]LL
publicList getUserByName(String name)throws :o:/RR p[
4jVd
HibernateException; I;{Ua*
TyR@3H
publicint getUserCount()throws HibernateException; SEM-t
G2=dq
publicList getUserByPage(Page page)throws ')WS :\J
530Kk<%^}8
HibernateException; A#F6~QX(.9
raMtTL+
} &}_tALg
|k: FNu]C
[E9_ZdBT
gU@R
(|tR>R.Wxg
java代码: +}f}!h;
rF/<}ye/4M
1CUI6@Cz)
/*Created on 2005-7-15*/ PaDm"+H@
package com.adt.dao.impl; ogdgLTi
K8v@)
import java.util.List; {J;(K~>?m
ABq#I'H#@2
import org.flyware.util.page.Page; ;;432^jD
e"Tr0k
import net.sf.hibernate.HibernateException; Q_k'7Z\g$
import net.sf.hibernate.Query; :4Y5
zpcO7AY~
import com.adt.dao.UserDAO; #Xi9O.
7v`~;}5
/** i06|P I
* @author Joa `mS0]/AV/
*/ -_>E8PhM
public class UserDAOImpl extends BaseDAOHibernateImpl b,#?LdQ%
lQ2vQz-J
implements UserDAO { Rvj[Csgi
AFWWGz
/* (non-Javadoc) J2!)%mF$
* @see com.adt.dao.UserDAO#getUserByName {t('`z
OXV9D:bIa
(java.lang.String) (%4O\s#l
*/ b C"rQJg
publicList getUserByName(String name)throws NLev(B:OQH
o"qG'\x
HibernateException { z'Ut9u
String querySentence = "FROM user in class cM=_i{c
4CxU
eq
com.adt.po.User WHERE user.name=:name"; 6PLdzZ{
Query query = getSession().createQuery wf~n>e^e
Gr~J-#a3~D
(querySentence); M"ZeK4qh
query.setParameter("name", name); PWS5s^WM
return query.list(); _$T.N
} S\@U3|Q5
y6>fK@K~
/* (non-Javadoc) t<SCrLbz
* @see com.adt.dao.UserDAO#getUserCount() w2V:g$~,
*/ Htce<H-P
publicint getUserCount()throws HibernateException { I5W#8g!{
int count = 0; "]yfx@)_
String querySentence = "SELECT count(*) FROM xp]_>WGq
jjg[v""3|
user in class com.adt.po.User"; 9gETWz(3I
Query query = getSession().createQuery H `_{n<
if+97^Oy
(querySentence); @.h;k4TD
count = ((Integer)query.iterate().next [:l=>yJ{(
D|/
4),v
()).intValue(); F2',3
return count; xepp."O
} bqQR";
F>aaUj
/* (non-Javadoc) awOH50R
* @see com.adt.dao.UserDAO#getUserByPage f}Uf*Bp
hJ~=eYK?J
(org.flyware.util.page.Page) E7@m& R
*/ 1*OZu.NdK
publicList getUserByPage(Page page)throws ;sY n=r
$6/CTQ
HibernateException { Vd A!tL
String querySentence = "FROM user in class 3d(:Y6D)
y2>AbrJ
com.adt.po.User"; 32K
Query query = getSession().createQuery \C"hL(4-
A7zL\U4
(querySentence); EskD)Sl
query.setFirstResult(page.getBeginIndex()) '-rRD\"q
.setMaxResults(page.getEveryPage()); i0&W}Bb'
return query.list(); rpv<'$6
} lT;uL~j
&>vfm9
} n?8xRaEf
@gjA8mL
@"/:Omh
0W]vK$\F*
A{ . A1
至此,一个完整的分页程序完成。前台的只需要调用 /vw$3,*z
M)sAMfuUw
userManager.listUser(page)即可得到一个Page对象和结果集对象 ^NFL3v8
f_| =EQ
的综合体,而传入的参数page对象则可以由前台传入,如果用 G@o\D-$
i?'|}tK
webwork,甚至可以直接在配置文件中指定。 '_FxxLAO
lZ?YyRsa6&
下面给出一个webwork调用示例: 6sNw#pqh
java代码: sQLjb8!7
ria.MCe\!
";
mlQyP
/*Created on 2005-6-17*/ @
[%K D
package com.adt.action.user; ?~tx@k$;Es
NPLJ*uHH
import java.util.List; E[c6*I
&|fWtl;43
import org.apache.commons.logging.Log; LMI7Ih;
import org.apache.commons.logging.LogFactory; ]+T$D
import org.flyware.util.page.Page; )Qh*@=$-
4,?WNPqo
import com.adt.bo.Result; -mG ,_}F
import com.adt.service.UserService; @81N{tg-
import com.opensymphony.xwork.Action; B9S@G{`
|P7FPmn
/** UZJ#/x5F
* @author Joa N@V:nCl
*/ YhL^kM@c
publicclass ListUser implementsAction{ !JA//{?
%\Mc6
privatestaticfinal Log logger = LogFactory.getLog ^CP>|JWD^
5'n$aFqI
(ListUser.class); ,n&Lp
nRs:^Q~o
private UserService userService; DY1"t7
9E
T%w5%{dqJ
private Page page; #q6#nfi"
;3+_aoY
privateList users; hp}JKj@
c"/Hv
/* =A(Az
* (non-Javadoc) Ht|"91ZC5
* )oy+-1dE
* @see com.opensymphony.xwork.Action#execute() ogJ *
*/ SZ~lCdWad
publicString execute()throwsException{ \Yh*ywwP#
Result result = userService.listUser(page); J>1%*Tz
page = result.getPage(); p;~oIy\,
users = result.getContent(); "%#CMCE|f
return SUCCESS; m|Sf'5fK
} _}tPtHPa/
XT1P.
w[aA
/** -?NAA]P5c@
* @return Returns the page. Ugme>60`'k
*/ &FWz7O>1
public Page getPage(){ y:Aha#<
return page; K?>sP%m)
} %JI*)K1WI
:"cKxd
/** !\cVe;<r
* @return Returns the users. mSGpxZ,IE
*/ dF*M"|[
publicList getUsers(){ BDLJDyf B
return users; >96+s)T%;
} P3v4!tR
m@2=vq1f
/** v>_83P`
* @param page }:(;mW8
D
* The page to set. ??lsv(v-
*/ >X*Y jv:r
publicvoid setPage(Page page){ oA3;P]~[
this.page = page; dFmpx%+p
} )>@%;\qV
tl`x/
/** 4RfBXVS
* @param users )&l5I4CIf
* The users to set. W
j`f^^\HJ
*/ H-mQ{K^
publicvoid setUsers(List users){ ElK Md
this.users = users; ;te( {u+
} /T+%q#4
Q{CRy-ha
/** +.zX?}
* @param userService Lcf?VV}
* The userService to set. q*kLi~Oe
*/ O%w'nz"
publicvoid setUserService(UserService userService){ A(H2Gt
D
this.userService = userService; w|ahb
} BCtKxtbS
} ct<XKqbI
P)LOAe1'
./^8L(
BqUwvB4
>XX93
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, N1sdWXG
r! [Qpb-:
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 ]c
bXI
bh#6yvpMR
么只需要: R<O Rw]
java代码: %(]B1Zg6,
?FwHqyFVlQ
F{rC{5@fj
<?xml version="1.0"?> h
B_p
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork eu":\ks
.gt;:8fw{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- h<8c{RuoZC
DiGHo~f
1.0.dtd"> #2"'tHf4
JSmg6l?[u
<xwork> DLD9
pF9WKpzE
<package name="user" extends="webwork- @Ae&1O;Zh
Onou:kmf1
interceptors"> 53d`+an2
%UhLCyC/
<!-- The default interceptor stack name
V<?0(esgR
J3e'?3w[
--> At
!:d3
<default-interceptor-ref 5NhAb$q2Y
/I{K_G@
name="myDefaultWebStack"/> 6q!Q([D_
a .?AniB0
<action name="listUser" AEDBr <
Qwve-[
class="com.adt.action.user.ListUser"> }RKsS3}
<param )>U"WZ'<
BPm")DMo
name="page.everyPage">10</param> 4'`H H
<result j}`ku9S~
ecO$L<9>
name="success">/user/user_list.jsp</result> ZS=;)
</action> 7oc Ng
/-t!)_zvw
</package> {u9n?Z%
BE],PCpPr
</xwork> e@S$[,8
_a|g
>
H q?F @X
;' |CSjco
^:mKTiA-
TTbJ9O<43
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 U2tgBF?)A
P}( c0/
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 aBQ@n
L/,gD.h^
注:上面的<param>的配置,还需要webwork和Spring整合的配合。
?^MH:o
[O|c3;
!q$>6P
7y42)X
X+<9-]=
我写的一个用于分页的类,用了泛型了,hoho .j"heYF)
6}0_o[23
java代码: JUXBMYFus
w7Mh8'P54
2PUB@B'
+
package com.intokr.util; 2
e#"JZ=
Z#[%JUYp'
import java.util.List; =|dm#w_L"
xDSiTp=)O
/** o1b.a*SZ
* 用于分页的类<br> HZS.%+2
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~m0=YAlk?
* R/Sm
* @version 0.01 KL9JA;"
* @author cheng )56L`5#tS
*/ 'MB+cz+v
public class Paginator<E> { | z_av
privateint count = 0; // 总记录数 7}~nQl2
privateint p = 1; // 页编号 B<h4ZK%
privateint num = 20; // 每页的记录数 ~k?t
privateList<E> results = null; // 结果 Z![#Uz.z
s|Vs#o.P)
/** l&"bm C:xr
* 结果总数 V~5vR`}
*/ I$)9T^Ra
publicint getCount(){ u:J4Az^!
return count; ;- Vs|X
} #)#'^MZX
^L
Xr4
publicvoid setCount(int count){ RU=g|TL
this.count = count; mUR[;;l
} z~v-8aw
{l_D+B;
/** XRyeEwA;pp
* 本结果所在的页码,从1开始 7)Tix7:9S;
* `Pwf?_2n-
* @return Returns the pageNo. t*6C?zEAU
*/ KVViTpZ
publicint getP(){ 9c1q:>|
return p; ~{kA;uw
} 3=UufI
_n4`mL8>kH
/** "/UPq6
* if(p<=0) p=1 FgPmQ
* ^BI&-bR@
* @param p Yx ;j
*/ Ml+f3#HP
publicvoid setP(int p){ @e7_&EGR?
if(p <= 0) AO5a
p = 1; pH@yE Vf
this.p = p; o5Knot)Oy
} y6s/S.
Gt !Hm(
/** 0{?%"t\/f
* 每页记录数量 <!|=_W6
*/ td#m>S
publicint getNum(){ >Wpd q( o
return num; xu;^F
} v57Kr ,
_qQo}|/q
/** eMH\]A~v"
* if(num<1) num=1 _,- \;
*/ /`O'eH
publicvoid setNum(int num){ r&L1jT.
if(num < 1) sn@)L ~$V
num = 1; tfe'].uT
this.num = num; ?C6`
} !W=2ZlzS
6b!1j,\Vx
/** EVbDI yFn
* 获得总页数 M49Hm[0(
*/ Z \-
publicint getPageNum(){ <)@^TRS
return(count - 1) / num + 1; Ax!fvcsN
} %';DBozZ
&0-Pl.M
/** MpJx>0j/J
* 获得本页的开始编号,为 (p-1)*num+1 HsK52<
*/ 6M8(KN^
publicint getStart(){ G&7 } m
return(p - 1) * num + 1; WxF@'kdn*,
} z&[[4[
q0\$wI
/** .q$/#hN:e
* @return Returns the results. UX'tdB
!A
*/ ,k/<Nv;
publicList<E> getResults(){ @;d7#!:cE
return results; @{8805Dp
} h3A|nd>\
OL#RkD
public void setResults(List<E> results){ MK4CggoC
this.results = results; v8A{q
} %M05& <
w;^7FuBaC
public String toString(){ \G1(r=fU
StringBuilder buff = new StringBuilder W{;LI
WsZ
_Hq)mF
(); O,KlZf_B
buff.append("{"); . J*2J(T,
buff.append("count:").append(count); ~3m}
EL
buff.append(",p:").append(p); ~bJ*LM?wOP
buff.append(",nump:").append(num); F?TmOa0
buff.append(",results:").append rYr.mX
QgX[?2
(results); Q|cA8Fn
buff.append("}"); 2c<phmiK
return buff.toString(); & |o V\L
} &]/.=J
fBt7#Tc=U
} MMUw+jM4
&rxR"^x\
aD3Q-a[