Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .x.]`b(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 l
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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 !cLo>,4
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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 8.=BaNU
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分页支持类: $am$EU?s
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java代码: wqs?828x
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package com.javaeye.common.util; hJ? O],4J
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import java.util.List; #&k5d:
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publicclass PaginationSupport { ,0Hr2*p
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publicfinalstaticint PAGESIZE = 30; 4G0m\[Du
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privateint pageSize = PAGESIZE; |O+H[;TB6
)
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privateList items; +oML&g-g_
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privateint totalCount; @)M9IOR
: /N0!&7
privateint[] indexes = newint[0]; 9};8?mucr
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privateint startIndex = 0; FUb\e-Q=
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public PaginationSupport(List items, int u@M,qo`
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totalCount){ MYvY]Jx3
setPageSize(PAGESIZE); 'ya{9EdlT
setTotalCount(totalCount); yYYSeH
setItems(items); EGS)b
setStartIndex(0); (gU!=F?#m
} T/~f~Z z
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public PaginationSupport(List items, int j0aXyLNX
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totalCount, int startIndex){ 50wulGJud
setPageSize(PAGESIZE); wv1iSfW
setTotalCount(totalCount); gO- _
setItems(items); <2x^slx)?
setStartIndex(startIndex); i$#;Kpb`^
} O+]ZyHnB
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public PaginationSupport(List items, int KYI/
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totalCount, int pageSize, int startIndex){ "m8^zg hL
setPageSize(pageSize); %OCb:s
setTotalCount(totalCount); ~jk|4`I?T
setItems(items); tw/dD +
setStartIndex(startIndex); 9:|{6_Y
} #q$HQ&k
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publicList getItems(){ O
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return items; lgy<?LI\
} !i}w~U<
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publicvoid setItems(List items){ ueWEc^_>
this.items = items; |aS.a&vwR
} b. '-?Nn
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publicint getPageSize(){ MJO-q $)c
return pageSize; ksUcx4;a@F
} -d/
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publicvoid setPageSize(int pageSize){ pYEMmZ?L
this.pageSize = pageSize; 7xlkZF
} 8kIksy
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publicint getTotalCount(){ ML
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return totalCount; )2o?#8J
} O8r|8]o
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publicvoid setTotalCount(int totalCount){ b_taC^-l
if(totalCount > 0){ |>^JRx
this.totalCount = totalCount; Dml;#'IF3
int count = totalCount / #:_Kws>+
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pageSize; Dx?,=~W9
if(totalCount % pageSize > 0) LonxT&"!D
count++; Bkc4TO
indexes = newint[count]; i&fuSk EP
for(int i = 0; i < count; i++){ uH^-R_tQ
indexes = pageSize *
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i; K5h
} t=iIY`Md%
}else{ H%tdhu\e
this.totalCount = 0; %wy.TN
} >]TWXmx/w
} 9.-S(ZO
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publicint[] getIndexes(){ hi(;;C9
return indexes; 2F.;;Ab
} ADzhNfS
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publicvoid setIndexes(int[] indexes){ ]%H`_8<gc
this.indexes = indexes; }($5k]]clP
} tDcT%D {:
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publicint getStartIndex(){ (?c"$|^J
return startIndex; FVKTbvYn
} dZ@63a>>@
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publicvoid setStartIndex(int startIndex){ f8dB-FlMm
if(totalCount <= 0) &p@O_0nF
this.startIndex = 0;
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elseif(startIndex >= totalCount) Yj49t_$b
this.startIndex = indexes v\ )W?i*l
M%m4i9~!?
[indexes.length - 1]; (L&d!$,Dv
elseif(startIndex < 0) [z{1*Xc
this.startIndex = 0; g!|kp?
else{ =dKtV.L
this.startIndex = indexes _B<X`L
=
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[startIndex / pageSize]; $UWZDD
} 6bC3O4Rw
} _`T_">9r
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publicint getNextIndex(){ S,UDezxg
int nextIndex = getStartIndex() +
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pageSize; T8$y[W-c
if(nextIndex >= totalCount) V 5mTP'
return getStartIndex(); u*`GiZAO
else Vc Z3
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return nextIndex; #X1ND
} |Rk@hzM2S
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publicint getPreviousIndex(){ WOap+
int previousIndex = getStartIndex() - TC*g|d @b
#*Ctwl,T
pageSize; 3s#N2X;Bc
if(previousIndex < 0) y<Ot)fa$
return0; F]&*ow
else +mn[5Y} :
return previousIndex; q/,O\,
} Q;rX;p^W
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} z
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抽象业务类 4V`G,W4^J
java代码: G"t5nHY\.
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/** ` Sz}`+E
* Created on 2005-7-12 Km$\:Xo
*/ 9%9#_?RW
package com.javaeye.common.business; Dlvz)
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import java.io.Serializable; k<?b(&`J
import java.util.List; dy[X3jQB
YT,{E,U;
import org.hibernate.Criteria; (4nq>;$3
import org.hibernate.HibernateException; OneY_<*a<
import org.hibernate.Session; Q=$2c[Uk
import org.hibernate.criterion.DetachedCriteria; J|7 3.&B
import org.hibernate.criterion.Projections; >hIu2jm
import 3bI9Zt#J%&
es7=%!0
org.springframework.orm.hibernate3.HibernateCallback; &oMh]Z*:
import "w<#^d_6
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org.springframework.orm.hibernate3.support.HibernateDaoS ZN0P:==
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upport; 1'Dai `
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import com.javaeye.common.util.PaginationSupport; OjA,]Gv6
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public abstract class AbstractManager extends 9\(|
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HibernateDaoSupport { p]c%f2E>d
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privateboolean cacheQueries = false; hhvyf^o
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privateString queryCacheRegion; K|=A:
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publicvoid setCacheQueries(boolean !&E-}}<
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cacheQueries){ Ow,b^|
this.cacheQueries = cacheQueries; 8z\xrY
} j?QDR
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publicvoid setQueryCacheRegion(String 8u]2xB=K
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queryCacheRegion){ dPRra{
this.queryCacheRegion = WNc0W>*NE1
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queryCacheRegion; U6s[`H3I{
} f|(M.U-
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publicvoid save(finalObject entity){ \~ wMfP8
getHibernateTemplate().save(entity); d0>
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} G3v5KmT
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publicvoid persist(finalObject entity){ _)-o1`*-
getHibernateTemplate().save(entity); \fe]c :
} d #wVLmKZ
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publicvoid update(finalObject entity){ pfI&E#:5
getHibernateTemplate().update(entity); /Z4et'Lo
} Dvln/SBk
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publicvoid delete(finalObject entity){ TD_Oo-+\
getHibernateTemplate().delete(entity); *Pg2c(Vg
} ySI!d|_
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publicObject load(finalClass entity, PPsE${!
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finalSerializable id){ =Fl^`*n
return getHibernateTemplate().load P!k{u^$L
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(entity, id); +"VP-s0
} )`D:F>p*
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publicObject get(finalClass entity, /Ci<xmP
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finalSerializable id){ $ME)#(
return getHibernateTemplate().get !|>"o7
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(entity, id); ~Cjn7
} a[TMDU;(/4
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publicList findAll(finalClass entity){ u#SWj,X
return getHibernateTemplate().find("from 3+bt~J0
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" + entity.getName()); t#"Grk8Mz&
} {l>hMxij
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publicList findByNamedQuery(finalString Y6d@h? ht
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namedQuery){ Du){rVY^d
return getHibernateTemplate sx<%2
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().findByNamedQuery(namedQuery); DlNX 3
} nFs(?Rv*
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publicList findByNamedQuery(finalString query, ;A!BVq
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finalObject parameter){ Q NVa?'0"Y
return getHibernateTemplate 8dyg1F
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().findByNamedQuery(query, parameter); {]|J5Dgfe
} X\F|Tk3_
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publicList findByNamedQuery(finalString query, =nHgDrA_
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finalObject[] parameters){ t&DEb_"De
return getHibernateTemplate jF*j0PkNdb
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().findByNamedQuery(query, parameters); ~F7gP{r
} ^G-@06 /!
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publicList find(finalString query){ 4xJQ!>6
return getHibernateTemplate().find >yh2Lri
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(query); >@AB<$A
} RCLeA=/N@0
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publicList find(finalString query, finalObject u>/ TE
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parameter){ g$o&Udgs
return getHibernateTemplate().find BL58] P84
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(query, parameter); 2dgd~
} !5?<% *
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public PaginationSupport findPageByCriteria dnuu&Rv
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(final DetachedCriteria detachedCriteria){ r!{Up7uL
return findPageByCriteria /|#fejPh
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Fea(zJ_
} -s'-eQF J
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public PaginationSupport findPageByCriteria BDZ?Ez\Sg
{cw /!B
(final DetachedCriteria detachedCriteria, finalint 7})[lL`\s
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startIndex){ 5QO9Q]I#_\
return findPageByCriteria jm r"D>
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(detachedCriteria, PaginationSupport.PAGESIZE, w"&n?L
t@+}8^M
startIndex); :S(ZzY
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} W'u>#
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public PaginationSupport findPageByCriteria yJe>JK~)
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(final DetachedCriteria detachedCriteria, finalint Yk Qd
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pageSize, |)/aGZ+
finalint startIndex){ sds"%]rg
return(PaginationSupport) QoH6
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getHibernateTemplate().execute(new HibernateCallback(){ !m?-!:
publicObject doInHibernate d9|<@A
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(Session session)throws HibernateException { tcog'nAz
Criteria criteria = y Fq&8 x<X
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detachedCriteria.getExecutableCriteria(session); hqkz^!rp
int totalCount = URbletSBQ
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((Integer) criteria.setProjection(Projections.rowCount >t_6B~x9
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()).uniqueResult()).intValue(); t}tEvh
criteria.setProjection G?Hdq;
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(null); 4)o
List items = h;NYdX5
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criteria.setFirstResult(startIndex).setMaxResults OY@ %p}l
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(pageSize).list(); PXNh&N
PaginationSupport ps = WVvvI9
ls)%c
new PaginationSupport(items, totalCount, pageSize, {h`uV/5@`
'K,:j 388
startIndex); <0q;NrvUb
return ps; WX6&oy>
} q;)JISf.
}, true); ]- QA'Lq
} l0A&9g*l2
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public List findAllByCriteria(final 'Ne@e)s9
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DetachedCriteria detachedCriteria){ m$T-s|SY
return(List) getHibernateTemplate 0F><P?5
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().execute(new HibernateCallback(){ d)f :)Ew
publicObject doInHibernate _/5H l`
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(Session session)throws HibernateException { [Nbm|["q~
Criteria criteria = ]yPqLJ
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); l$bu%SZ
} I,@6J(9
}, true); ><HE;cVg?
} ,f;}|d:r
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public int getCountByCriteria(final oWo-
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DetachedCriteria detachedCriteria){ a ]tVd#
Integer count = (Integer) M, mvys$
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getHibernateTemplate().execute(new HibernateCallback(){ oJ|j#+Ft
publicObject doInHibernate s
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(Session session)throws HibernateException { d-r@E3
Criteria criteria = 7!TueP0Zd
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detachedCriteria.getExecutableCriteria(session); Oh6fj}eK
return +@k+2?]
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criteria.setProjection(Projections.rowCount =uYYsC\T
o@i#|kx,
()).uniqueResult(); vbe|hO""
} :; fHDU|
}, true); 3r."j2$Hs0
return count.intValue(); mahJSz(3
} c?&X?<
} s6.M \^
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用户在web层构造查询条件detachedCriteria,和可选的 F Yzi~L
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %
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PaginationSupport的实例ps。 hD*SpVIU
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ps.getItems()得到已分页好的结果集 WE.{p>
ps.getIndexes()得到分页索引的数组 ll.N^y;a
ps.getTotalCount()得到总结果数 Jx7C'~,J
ps.getStartIndex()当前分页索引 qjdMqoOCjl
ps.getNextIndex()下一页索引 5T2CISmu
ps.getPreviousIndex()上一页索引 2:7zG"$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ';jYOVe
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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 v>Yb/{A
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一下代码重构了。 Hmd]
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我把原本我的做法也提供出来供大家讨论吧: 6dN7_v)
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首先,为了实现分页查询,我封装了一个Page类: lpeEpI/gM
java代码: wKYZa# u
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/*Created on 2005-4-14*/ aM2l2
package org.flyware.util.page; ?Exv|e
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/** oe
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* @author Joa m~P CB_ifW
* o(
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*/ =;3Sx::=
publicclass Page { Iw&vTU=2
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/** imply if the page has previous page */ C8e
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privateboolean hasPrePage; 9S7kUl{
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/** imply if the page has next page */ h[1MtmNw
privateboolean hasNextPage; X;B\Kj`n
[t7]{d*
/** the number of every page */ i2YuOV!
privateint everyPage; Q}K#'Og
\h D dU+
/** the total page number */ z4+k7a@jn
privateint totalPage; [16cFqD
T:Hr&ws4
/** the number of current page */ M?:c)&$]D
privateint currentPage; OK6]e3UO
;04Ldb1{|3
/** the begin index of the records by the current e8]\U/
8V)^R(\;
query */ r>"
privateint beginIndex; *x])Y~oQ
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/** The default constructor */ 3k#/{Z
public Page(){ }YMy6eW4
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} y[\VUzD*'
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/** construct the page by everyPage 2f:Eof(B
* @param everyPage }i`PGx
* */ {Jx4xpvPo
public Page(int everyPage){ gu<'QV"
this.everyPage = everyPage; ("+}=*?OF3
} kc @[9eV
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/** The whole constructor */ Q7$.LEioN
public Page(boolean hasPrePage, boolean hasNextPage, @,u/w4
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int everyPage, int totalPage, Z@&Dki
int currentPage, int beginIndex){ 1_
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this.hasPrePage = hasPrePage; 9h%?QC
this.hasNextPage = hasNextPage; (+u39NQV
this.everyPage = everyPage; J-)
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this.totalPage = totalPage; \XM^oE#G
this.currentPage = currentPage; D]W$?(=4
this.beginIndex = beginIndex; 9}uW}yJ
} )\be2^p
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/**
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* @return YoLx>8
* Returns the beginIndex. D3^7y.u<)
*/ 'XofD}dm
publicint getBeginIndex(){ I_%a{$Gjl
return beginIndex; %4
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} EG0auzW?
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/** 9,_mS{+B
* @param beginIndex ] GTAq
* The beginIndex to set. $:j G- r
*/ E V^~eTz
publicvoid setBeginIndex(int beginIndex){ 4e;yG>
this.beginIndex = beginIndex; GbA.UM~
} f<*Js)k
nJ"YIT1K]p
/** )aao[_ZS
* @return VX+jadYdq
* Returns the currentPage. MJCzo |w
*/ hL;8pE8
publicint getCurrentPage(){ ""h)LUrl
return currentPage; )a3J9a;ZS0
} ,H2D
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/** UH>F|3"d
* @param currentPage a/U2xq{x
* The currentPage to set. PN<C=gAe
*/ a9Z%JS]
publicvoid setCurrentPage(int currentPage){ Ppt2A6W
this.currentPage = currentPage; 80 Y\|)
} )r
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uy^
/** `^Eae
* @return N2$I}q%
* Returns the everyPage. c$`4*6
*/ 7,MS '2nz
publicint getEveryPage(){ X3:XTuV
return everyPage; V0(o~w/W%!
} z%7SrUj2
rVa?JvDO=
/** 6ubL1K
* @param everyPage fr}Eaa-{^
* The everyPage to set. X _G| hx
*/ j:&4-K};Z`
publicvoid setEveryPage(int everyPage){ 'K*AV7>E
this.everyPage = everyPage; K+)%KP
} zYv#:>C8
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{
/** q;D+ai
* @return #:|+XLL
* Returns the hasNextPage. {d%&zvJnD
*/ 'snn~{hG
publicboolean getHasNextPage(){ 5,;`$'?a%
return hasNextPage; G"59cv8z4R
} KkMay
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/** (ihP`k-.
* @param hasNextPage q$.{j"cZV
* The hasNextPage to set. dg7=X{=9jv
*/ KZe)K_1[
publicvoid setHasNextPage(boolean hasNextPage){ tYqs~B3
this.hasNextPage = hasNextPage; %77p5ctW
} 1b>C<\
#4h+j%y[H
/** p|/j4@-h
* @return NHgjRPz"
* Returns the hasPrePage. n*'<uKpM
*/ Grz 3{U
publicboolean getHasPrePage(){ 0 Hw-59MK
return hasPrePage; xf>z @)e
} |nk3^;Yf
"SoHt]%#
/** 5ZPzPUa8~
* @param hasPrePage Q2%QLM:.,
* The hasPrePage to set. O:/yAc`
*/ 0l#)fJo
publicvoid setHasPrePage(boolean hasPrePage){ RF!1oZ
this.hasPrePage = hasPrePage; :9Y$'+ <&H
} =}fd6ea(o
@C-dG7U.P
/** R,!Q
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* @return Returns the totalPage. daAyx-
* TfZ6F8|B
*/ ;#)mLsl
publicint getTotalPage(){ JH]K/sC>
return totalPage; |m?vVLq
} 2~p[7?sp'
}5O>EXE0R
/** hc$@J}`
* @param totalPage ~ZlC
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* The totalPage to set. Zz |MIGHm
*/ Bl1Z4` 3
publicvoid setTotalPage(int totalPage){ rn:!dV[
this.totalPage = totalPage; |"$uRV=qm
} 0-3rQ~u
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}
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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 GfyX'(ge
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个PageUtil,负责对Page对象进行构造: bv
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java代码: Er:?M_ev
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/*Created on 2005-4-14*/ `
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package org.flyware.util.page; B7-RU<n
9f}XRz
import org.apache.commons.logging.Log; [{<dbW\ 9
import org.apache.commons.logging.LogFactory; 6a>H|"PNE
W*xX{$NL
/** >^"BEG9i:
* @author Joa M`,XyIn
* P8gXCX!>U
*/ gKb0)4 AK
publicclass PageUtil { .Nx
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privatestaticfinal Log logger = LogFactory.getLog H.J5i~s
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(PageUtil.class); =ziy`#fm,
*R`MMm
/** PG)_L.7rJ
* Use the origin page to create a new page )3muPMaY
* @param page $
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* @param totalRecords F}rPY:
* @return 4W\,y_Q o
*/ ]Bb7(JX
publicstatic Page createPage(Page page, int mKg@W;0ML
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totalRecords){ GZ0aOpUWVq
return createPage(page.getEveryPage(), dNVv4{S
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page.getCurrentPage(), totalRecords); qq+MBW*
} $-@$i`Kf/
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/** O
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* the basic page utils not including exception 1 2]fQkp
nY) .|\|i
handler de-0?6
* @param everyPage ZZ
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* @param currentPage i@<~"~>]7
* @param totalRecords |r~
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* @return page j+748QAhh
*/ bGh0<r7R
publicstatic Page createPage(int everyPage, int %7`d/dgR
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currentPage, int totalRecords){ ?'~;Q)
everyPage = getEveryPage(everyPage); ~Y/z=^
currentPage = getCurrentPage(currentPage); o G_~3Kt
int beginIndex = getBeginIndex(everyPage, ~B@}R
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currentPage); wt7.oKbW
int totalPage = getTotalPage(everyPage, Xn7[n
+6%7CC 6
totalRecords); l6B.6
'4)w
boolean hasNextPage = hasNextPage(currentPage, T~Y g5J
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totalPage); TJ2/?p\x
boolean hasPrePage = hasPrePage(currentPage); iiwpSGFl]
uaQ&&5%%J
returnnew Page(hasPrePage, hasNextPage, ,e ELRzjl
everyPage, totalPage, uU+s!C9r
currentPage, \!X?zR_
j3P RAe
beginIndex); Rx.
rj~
} tm xP Oe
%^^h) Wy}
privatestaticint getEveryPage(int everyPage){ rr>~WjZ3
return everyPage == 0 ? 10 : everyPage; S.fXHtSx
} ti;%BS
_XN~@5elrC
privatestaticint getCurrentPage(int currentPage){ `03<0L
return currentPage == 0 ? 1 : currentPage; 9c5!\m1
} >1XL;)IL>
d x359
privatestaticint getBeginIndex(int everyPage, int x9*ys;~w
g@(30{
currentPage){ mahi7eU
P
return(currentPage - 1) * everyPage; m0iV m|
} x[m'FsR4
F>Mr<k=@;
privatestaticint getTotalPage(int everyPage, int U~g@TfU;
rAatJc"0
totalRecords){ S1>Z6
int totalPage = 0; WRMz]|+}4
/2:Q6J
if(totalRecords % everyPage == 0) cJq<9(
totalPage = totalRecords / everyPage; KS>Fl->
else 2wOy}:
totalPage = totalRecords / everyPage + 1 ; I;iR(Hf)?q
lWl-@*'
return totalPage; w})NmaT;YF
} [xS5z1;
JE%i-UVH+;
privatestaticboolean hasPrePage(int currentPage){ l_sg)Vr/b
return currentPage == 1 ? false : true; v =bv@c
} bG1 ofsU
wL|7mMM,
privatestaticboolean hasNextPage(int currentPage, hd=j56P5P
= P8~n2V
int totalPage){ IgiqFV{
return currentPage == totalPage || totalPage == w\v&3T
I_L;T
0 ? false : true; { ;' :h
} B(EtXB9
B$EK_@M
Oylp:_<aT
} R^?PAHE7
j<|6s,&
9e76pP(
$@4e(Zrmo
l2M/,@G
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ;W4:#/~14
Ty iU1, oO
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 [EcV\.
4}PeP^pj
做法如下: K+t];(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0wYiu
n%8#?GC`
的信息,和一个结果集List: YmA) @1@U
java代码: zXDd,ltm
[@s=J)H
9M19UP&
/*Created on 2005-6-13*/ E-[:.
&
package com.adt.bo; |3W3+Rn!
7vdHR\#;$
import java.util.List; qFGB'mIrFz
(T`q++
import org.flyware.util.page.Page; y#GCtkhi
)[RpZpd`*
/** D)RdOldr
* @author Joa >R) F}
*/ %!W6<ioW
publicclass Result { 6;[1Jz]?i
rGAFp,}-f
private Page page; ]s}aC9I
>pJ6{Ip
private List content; cEtZ}2,j
8:BQHYeJK
/** oO}>i0ax*
* The default constructor X$ejy/+.
*/ s:G[Em1
public Result(){ gx&\Kw6HM
super(); @b>YkJDk
} q8tP29
{!>E9Px
/** =54Vs8.
* The constructor using fields )OS>9
kFH
* " Tw0a!
* @param page e*6U |+kJ
* @param content +KYxw^k}"7
*/ @ICejB<
public Result(Page page, List content){ =k_XKxd
this.page = page; `mWQWx$V!
this.content = content; o7hH9iY
} y`T--v3mI
Y|Nfwqz
/** a'o}u,e5
* @return Returns the content. ,OFq'}q
*/ w@4t$bd7
publicList getContent(){ oT$(<$&<
return content; +YkmLD
} v_[)FN"]Y.
F?!};~$=Z
/** fB@K'JQG
* @return Returns the page. nA|gQibA
*/ kwDjK"
public Page getPage(){ 1NB2y[
return page; (0Zrfu^
} `,hW;p>-
5 >0\e_V
/** 0]/,m4a#n
* @param content 0#2T0zk
* The content to set. xop-f#U*
*/ BvNl?A@]A
public void setContent(List content){ v[p/c.p?i
this.content = content; {-:4O\/
} w i![0IE )
~Tpe,juG_
/** n$}R/*
* @param page
o9DYr[
* The page to set. ~pDRF(
*/ m1M;'tT@
publicvoid setPage(Page page){ u-]vK
this.page = page; g!~-^_F
} nEeQL~:
} `lH1IA/3
FCUVP,"T
rQ9?N^&!%
}L{_xyi>#
d;*OO xQV
2. 编写业务逻辑接口,并实现它(UserManager, |*/uN~[
wC4AVJJ^>
UserManagerImpl) `!5tH?bX
java代码: $cp16
UeutFNp
e3oYy#QNk
/*Created on 2005-7-15*/ G!>
iqG
package com.adt.service; `[g#Mxw
N{0+C?{_
import net.sf.hibernate.HibernateException; )VV4HoH]8
:G6 xJlE|
import org.flyware.util.page.Page; ~_/<PIm
'=Ip5A{S /
import com.adt.bo.Result; v '"1/% L
rH
[+/&w5
/** E.WNykF-
* @author Joa 9Y!0>&o
*/ DkF@XK0c3
publicinterface UserManager { Wme1Uid
*_<SWTE
public Result listUser(Page page)throws TV$\v@\ =
}+QhW]nO{F
HibernateException; 6_ 33*/>=c
BIHHRCe:@n
} \]~kyy
r P<d[u
3thG*^C5
P^uP$D
LRqw\fKk[
java代码: -=v/p*v0o
g9grfN
"'&>g4F`o
/*Created on 2005-7-15*/ d=c1WK
package com.adt.service.impl; P_^|KEz
/S2p ``E+
import java.util.List; ~Q{[fy=
k=d%.kg
import net.sf.hibernate.HibernateException; 6@ (k8<3
nEZ-h7lzl(
import org.flyware.util.page.Page; q:D0$YY0
import org.flyware.util.page.PageUtil; o q'J*6r
5Qm.ECXV
import com.adt.bo.Result; y:^>(l #;
import com.adt.dao.UserDAO; w;h\Y+Myyk
import com.adt.exception.ObjectNotFoundException; p8}5x 2F
import com.adt.service.UserManager; f;_K}23
1,*Z_ F=y
/** 1Q2k>q8
* @author Joa EFT02#F_f
*/ ,*O{jc`(
publicclass UserManagerImpl implements UserManager { WMdz+^\(
,sRrV $,"
private UserDAO userDAO; O. .@<.
~[
ks|
/** Cs~\FI1wR
* @param userDAO The userDAO to set. L2V
$%*6
*/ aLyhxmn ^)
publicvoid setUserDAO(UserDAO userDAO){ d
q+7K
this.userDAO = userDAO; 4.Jaw+
} d9Ow 2KrC
qkR,<"C|`
/* (non-Javadoc) 19YJ`(L`x
* @see com.adt.service.UserManager#listUser FclSuQWti
l52n/w#qFB
(org.flyware.util.page.Page) <EM LiiNY
*/ +oKpA\mz
public Result listUser(Page page)throws uN?O*h/(
:Jsz"vCg&s
HibernateException, ObjectNotFoundException { VQW)qOR9
int totalRecords = userDAO.getUserCount(); \Kzt*C-ZH
if(totalRecords == 0) 4d3]pvv
throw new ObjectNotFoundException si"mM>e
4'4s EjyA
("userNotExist"); b6E8ase:F
page = PageUtil.createPage(page, totalRecords); d8y=.
List users = userDAO.getUserByPage(page); 3<.j`JB@&
returnnew Result(page, users); i+
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} RWm Q]
@gVyLefS6g
} 7`'fUhB!
V
n!az}
5 xzB1n8
}FdcbNsP
Xta>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 eMPQ|
W
FoelOq6
询,接下来编写UserDAO的代码: pl^"1Z=*
3. UserDAO 和 UserDAOImpl: `b'|FKc]
java代码: \kJt@ [w%
3M:B?2
3S2p:\]
/*Created on 2005-7-15*/ (P52KD[A[
package com.adt.dao; kBQenMm
:
1f 5;]%N
import java.util.List; V/wc[p
~
r7BH{>-
import org.flyware.util.page.Page; ?}>Z_ ("
lO[jf6gB
import net.sf.hibernate.HibernateException; OB
I8~k
~9>[ U%D
/** ;g)Fhdy!
* @author Joa =A&*SE o5
*/ 5]n<%bP\
publicinterface UserDAO extends BaseDAO { !Pjg&19
-D^y)
publicList getUserByName(String name)throws EvardUB)
~b<4>"7y.
HibernateException; X]^E:'E!
>b"z`{tE
publicint getUserCount()throws HibernateException; {O,M}0Eg
VNEZBy"F
publicList getUserByPage(Page page)throws Ru\Lr=9
JX,#W!d
HibernateException; 3ijI2Zy
b)`#^uxxJ
} 9h0,L/;\
u|*|RuY
^3@a0J=F
O0*L9C/Q
pj-HLuZR
java代码: e8uIh[+ 0
/Rcd}rO
2bG4,M
/*Created on 2005-7-15*/ TdOWdPvYj
package com.adt.dao.impl; $=QO_t)?
F^bQ-
import java.util.List; xgw)`>p,W
Bst>9V&R
import org.flyware.util.page.Page; 7a_n\]t465
d"`>&8*
import net.sf.hibernate.HibernateException; K1{nxw!`
import net.sf.hibernate.Query; 'oeg[
{gHscj;SM
import com.adt.dao.UserDAO; z ex.0OT;
SIVLYi
/** X^ ]$/rI)
* @author Joa <hC3#dNRd
*/ 8PVs!?Nne
public class UserDAOImpl extends BaseDAOHibernateImpl _eeX]xSSl
v2=!*
implements UserDAO { [?6D1b[
yzzre>F
/* (non-Javadoc) 6uE1&-:L
* @see com.adt.dao.UserDAO#getUserByName ^dKaa
6e-h;ylS
(java.lang.String) '#
2J?f'
*/ i1\ /\^
publicList getUserByName(String name)throws bc}OmPE
SJ_cwYwI$
HibernateException { !w\;Q8irN
String querySentence = "FROM user in class 72.IhBNtT
DH*|>m&
com.adt.po.User WHERE user.name=:name"; ew ,ed U
Query query = getSession().createQuery BU{V,|10a
.-6s`C2
Y}
(querySentence); ,$ret@.H
query.setParameter("name", name); $ttr_4=
return query.list(); 2jBE+k"M
} 4$w-A-\t
BcO2* 3
/* (non-Javadoc) $5(%M8qmQ
* @see com.adt.dao.UserDAO#getUserCount() #;\;F PuZ
*/ `%I{l
publicint getUserCount()throws HibernateException { ##ea-"m8
int count = 0; #/=yz<B
String querySentence = "SELECT count(*) FROM 3t6'5{
Nmq5Tv
user in class com.adt.po.User"; mzR
@P$:36
Query query = getSession().createQuery =zGz|YI*?
Rk0rHC6[
(querySentence); Y[]t_o)
count = ((Integer)query.iterate().next MpvA--
9f[[%80
()).intValue(); Ybg`Z
return count; 6_><W"r:]
} (pNng"/
V]cY+4Y
/* (non-Javadoc) 1OeDWEcB
* @see com.adt.dao.UserDAO#getUserByPage )O(Gw-jWE
<4bo7XH
(org.flyware.util.page.Page) .]l2)OlLQ
*/ OB@t(KNx*P
publicList getUserByPage(Page page)throws g o Z#
`W S
HibernateException { ~H~4 fp b
String querySentence = "FROM user in class ~[,TLg
6
;$;/#8`>
com.adt.po.User"; p5BcDYOw`
Query query = getSession().createQuery /YR$#&N2
/aEQ3x
(querySentence); bx6}zkf&
query.setFirstResult(page.getBeginIndex()) \~1+T
.setMaxResults(page.getEveryPage()); tqC#_[~7
return query.list(); dK$dQR#
}
kS9
d7gSkna`5c
} |mA*[?ye@
bJ}+<##
h /Nt92
q0<`XDD`
Tr!X2#)A!
至此,一个完整的分页程序完成。前台的只需要调用 }PuO$
L
:AGQkJb
userManager.listUser(page)即可得到一个Page对象和结果集对象 Im#$iPIvT
"VCr^'
的综合体,而传入的参数page对象则可以由前台传入,如果用 :UciFIa
["/x~\c'N
webwork,甚至可以直接在配置文件中指定。 U\6DEnII?!
[D\AVx&
下面给出一个webwork调用示例: _s,svQ8#
java代码: \OH:xW~
[ RuY'
$^>vJk<
/*Created on 2005-6-17*/ 6*Qpq7Ml
package com.adt.action.user; xb>+~5 9:
yp/*@8%_E
import java.util.List; Rw%KEUDm
z<*]h^!3
import org.apache.commons.logging.Log; 'M/&bu r
import org.apache.commons.logging.LogFactory; \}W.RQ^3
import org.flyware.util.page.Page; 2uEu,YC
N*W.V,6yH
import com.adt.bo.Result; #1k,t
import com.adt.service.UserService; ocUu
import com.opensymphony.xwork.Action; u6RHn;b
H_]kR&F8
/** 58,mu#yq6
* @author Joa ;zODp+4@Q
*/ OwUbm0)h^V
publicclass ListUser implementsAction{ EG6fC4rfC
(H^o8J
privatestaticfinal Log logger = LogFactory.getLog LPF?\mf ^4
&9tsk#bA.g
(ListUser.class); @RW%EXKt
5 <poN)"
private UserService userService; 2T5ZbXc+x
*ni|I@8
private Page page; k=}hY+/=
*^()el,d
privateList users; ]ghPbS@
^lj>v}4fkW
/* ~ .-'pdz%
* (non-Javadoc) 0jH2.d=
* +>j_[O5Y
* @see com.opensymphony.xwork.Action#execute() g=Jfp$*[
*/ Vo()J4L
publicString execute()throwsException{ xH uyfQLk
Result result = userService.listUser(page); ipG+qj/=
page = result.getPage(); )&K%Me
users = result.getContent(); 6yqp<D0SP)
return SUCCESS; 'z/hj>B<
} XlPy(>
\&0NH=*^
/** >{Djx
* @return Returns the page. >E3OYa?G
*/ *6DKUCA/
public Page getPage(){ aL}_j#m{
return page; v3Kqs:"\
} PX]v"xf
C4,W[L]4"
/** lKcnM3n
* @return Returns the users. NT0q!r/!
*/ "-
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publicList getUsers(){ "PPwJ/L(
return users; 2cL<`
} u}$3.]-.?T
kmwFw>#
/** ~Q5HM
* @param page Wp $\>
* The page to set. *&s_u)b
*/ qW*)]s)z
publicvoid setPage(Page page){ G8VWx&RE
this.page = page; ! WNr09`
} }tN"C 3)@
Gwe9<
y
/** zK v}J
* @param users }/|1"D
* The users to set. rnUe/HjH
*/ JXrMtSp\
publicvoid setUsers(List users){ Nsb13mlY
this.users = users; Jc*A\-qC.
} LvS`
bA:abO
/** }/=_
* @param userService Yyf8B
* The userService to set. tP3Upw"U
*/ <?+\\Z!7
publicvoid setUserService(UserService userService){ Ad(j&P
this.userService = userService; gU:jx
} -4.+&'
} _
._'\
U:H*b{`TU
1jR<H$aS
xpae0vw
"b qB@)
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, bTJ7RqL
;TYkJH"
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 ~ ~&M&Fe
+u7mw<A
8
么只需要: GKX#-zsh79
java代码: IIzdCa{l
n=`UhC
EG,RlmcPp
<?xml version="1.0"?> z[th@!3
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork B|tP3<
(c;$^xZK
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;tO (,^
IsI\T8yfc
1.0.dtd"> xGjEEBL
[dL#0~CL$
<xwork> uTQ/_$
O:4.xe
<package name="user" extends="webwork- opKtSF|)
D9h\=[%e
interceptors"> Hly$ Wm
ZDlMkHJ
<!-- The default interceptor stack name m6s32??m
uv, t(a.^
--> _|3n h;-m
<default-interceptor-ref :2La,
I_Q '+d
name="myDefaultWebStack"/> >Py=H+d!j
UPH:$Fk&
<action name="listUser" mAz':R[
}2}hH0R
class="com.adt.action.user.ListUser"> "[76>\'H
<param >k"/:g^t
Zx@{nVoYe~
name="page.everyPage">10</param> EI'(
<result ,`K'qms
VK8 5A
name="success">/user/user_list.jsp</result> e tY9Pq
</action> WSL_Dc
tR1
kn&w
</package> ~Os~pTo
ip~PF5
</xwork> ^b'[81%
94Z~]C
m8.sHw
H'GyWG|Wx
d+$a5 [^9
OPar"z^EV
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 -3A#a_fu
xI$B",?(
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 .Gw;]s3
't]=ps
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,JX/`7y
ygh*oVHO
M(xd:Fa?
;a2TONW
42mdak}\
我写的一个用于分页的类,用了泛型了,hoho C*=#=.~~{
p "u5wJ_
java代码: ?Yxk1Y4ig)
jT%k{"+>+?
i!9yN:m0
package com.intokr.util; K[O'@v
>J+hu;I5
import java.util.List; )=#QTiJ
?J|~G{yH
/** k1W
q$KCwG
* 用于分页的类<br> iXeywO2nP
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0@vSl%I+
* r!'\$(m E
* @version 0.01 [;%qxAB/_
* @author cheng *s}dtJ
*/ "9aiin
public class Paginator<E> { ;
7k@_
privateint count = 0; // 总记录数 Mz_*`lRN
privateint p = 1; // 页编号 |}t[-a
privateint num = 20; // 每页的记录数 ;vnG
privateList<E> results = null; // 结果 W&qE_r
%&0_0BU
/** 8V?O=3<a
* 结果总数 HsO4C)/
*/ B/7c`V
publicint getCount(){ P
>HEV
a
return count; va[@XGaC3
} `L /\F,
NLf6}
publicvoid setCount(int count){ LNPwb1)
this.count = count; u?r=;:N|y
} *H8(G%a!^
$ac
VJI?
/** ,SNN[a
* 本结果所在的页码,从1开始 D<78Tm
x
* sE{A~{a`
* @return Returns the pageNo. {
<f]6
*/ LNOm"D?"
publicint getP(){ %#7Yr(&
return p; SjgjGJw
} .-Yhpw>f
Ksr.'
/** ;rC)*=4#
* if(p<=0) p=1 &z8I@^<
* W6:ei.d+NS
* @param p 80DcM9^t8
*/ S2T~7-
publicvoid setP(int p){ &;I=*B~kE$
if(p <= 0) n$&xVaF|
p = 1; ;H}XW=vO
this.p = p; ,'N8Ivt
} F l@%?
)%FRBO]
/** C7:;<<"P
* 每页记录数量 _Z'[-rcXWh
*/
wa7)
publicint getNum(){ ] ;"blB
return num; V~([{
} lC):$W
gJz~~g'
/** MZ]#9/
* if(num<1) num=1 SkU'JM7<95
*/ G;Jqby8d
publicvoid setNum(int num){ ^U OVXRn
if(num < 1) tj7{[3~-[
num = 1;
_8]hn[
this.num = num; fsRRnD
} M@%$9N)gd
KElzYZl8
/** 99)m d
* 获得总页数 3z5w}qN]M
*/ W(.q.Sx>
publicint getPageNum(){ >..C^8 "
return(count - 1) / num + 1; m$6u K0
} F6,[!.wl
) bRj'*
/** 2vbm=~)$F
* 获得本页的开始编号,为 (p-1)*num+1 (nL''#Ka
*/ @'XxMO[Z!<
publicint getStart(){ a8$gXX-2
return(p - 1) * num + 1; R{N9'2l:
} P4H%pm{-
2g?O+'JD
/** 8y:c3jzP_
* @return Returns the results. l.gt+e
*/ g<d#zzP"T
publicList<E> getResults(){ A|Z'\D0
return results; o$disJ
} CI%4!K;{
TX/Ng+v S
public void setResults(List<E> results){ n_ORD@$]
this.results = results; p{c+ +P5
} +eT1/x0
V)Oj6nD]
public String toString(){ OZ,%T9vP
StringBuilder buff = new StringBuilder {[Sd[P
m 3k}iIU7
(); WJD1U?`
buff.append("{"); \r4QS
buff.append("count:").append(count); {tqLH2cO
buff.append(",p:").append(p); *}\}@0%
buff.append(",nump:").append(num); #*r u*
buff.append(",results:").append [,_4#Zz
b3$aPwv
(results); [
QHSCF5
buff.append("}"); kta`[%KmIZ
return buff.toString(); ,AX7~;hpq
} I" AgRa
.@7J8FS*
} ZMFV iE;8
D
H}gvV
D`|.%