Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 vr2PCG[~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KU]o=\ak%
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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 %9S0!h\
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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 E7aG&K
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分页支持类: s2 :Vm\
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java代码: *0Fz." v
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package com.javaeye.common.util; %NC/zqPH~
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import java.util.List; !H9^j6|
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publicclass PaginationSupport { }@tgc?CD
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publicfinalstaticint PAGESIZE = 30; 9tVV?Q@)
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privateint pageSize = PAGESIZE; F qgs
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privateList items; p?4[nS-,
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privateint totalCount; HiH<'m"\.
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privateint[] indexes = newint[0]; Qf}.= (
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privateint startIndex = 0;
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public PaginationSupport(List items, int %2g<zdab
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totalCount){ FOMJRq
setPageSize(PAGESIZE); Q>rr?L`
setTotalCount(totalCount); (j??
setItems(items); d%-/U!z?
setStartIndex(0); '\xE56v)F
} .5}Gt>4XM
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public PaginationSupport(List items, int CS(2bj^6D
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totalCount, int startIndex){ v}d)uPl};
setPageSize(PAGESIZE); 5I^;v;F
setTotalCount(totalCount); ~T-uk
setItems(items); @7C.0>W_A
setStartIndex(startIndex); -57~7
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} 1;V_E2?V
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public PaginationSupport(List items, int f% )9!qeW
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totalCount, int pageSize, int startIndex){ : MjDcI~
setPageSize(pageSize); pq&[cA_w
setTotalCount(totalCount); LCtVM70
setItems(items); WulyMcJ
setStartIndex(startIndex); QeuM',6R
} NlKVl~_ C
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publicList getItems(){ #5z0~Mg-X
return items; \U>&W
} m6n%?8t
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publicvoid setItems(List items){ }l[e@6r F
this.items = items; ~~-VScG&
} -bHlFNRm
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publicint getPageSize(){ %'2.9dB
return pageSize; H${L F.8
} m:[I$b6AY
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publicvoid setPageSize(int pageSize){ 2HN*j~>i~
this.pageSize = pageSize; yxp,)os:
} ;<m`mb4x[
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publicint getTotalCount(){ WK(X/!1/k
return totalCount; ~U"m"zpLP
} 3c3;8h$k
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publicvoid setTotalCount(int totalCount){ B#jnM~fJz
if(totalCount > 0){ Xi[]8o
this.totalCount = totalCount; $KGMAg/H
int count = totalCount / #YE?&5t
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pageSize; 6` TwP\!$/
if(totalCount % pageSize > 0) R2sG'<0B0
count++; rVNx2
indexes = newint[count]; gI;"P kN
for(int i = 0; i < count; i++){ 'A7!@hVy
indexes = pageSize * NOXP}M
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i; KxX [8
} jo<xrn\
}else{ m]>zdP+
this.totalCount = 0; &3Zb?
} pS ](Emn`.
} Ul_Zn
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publicint[] getIndexes(){ E .Xp\Dm71
return indexes; c#{lXS^
} j*?8w(!
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publicvoid setIndexes(int[] indexes){ vF$(
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this.indexes = indexes; ?pW1}:z
} QX<n^W
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publicint getStartIndex(){ HqW /
return startIndex; A4,{ep'Z!
} Lxp}o7>K
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publicvoid setStartIndex(int startIndex){ R QQ'Wg
if(totalCount <= 0) _HHvL=
this.startIndex = 0; I2$DlEke
elseif(startIndex >= totalCount) 1,+<|c)T?
this.startIndex = indexes
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[indexes.length - 1]; e^O:I
elseif(startIndex < 0) ih0a#PB8
this.startIndex = 0; /&Oo)OB;
else{ Z8$BgP
this.startIndex = indexes Nz2V aZ
/Yy)=~t{
[startIndex / pageSize]; 7?whxi Qs
} RD:G9[
} W94:%
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publicint getNextIndex(){ 0! 3. .5==
int nextIndex = getStartIndex() + GfELL`yz
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pageSize; )%@7tx
if(nextIndex >= totalCount) EN2t}rua
return getStartIndex(); kku<0<(N
else 2V)+ba|+
return nextIndex; RdPk1?}K
} ^_ch%3}Im
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publicint getPreviousIndex(){ 3UUdJh<~
int previousIndex = getStartIndex() - L=#NUNiXr
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pageSize; T<0 r,
if(previousIndex < 0) e El)wZ,A
return0; F
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else wvq4 P
return previousIndex; i6KfH\{N
} .3C::~:
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} v`,!wS
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抽象业务类 E_=F'sP?
java代码: $~6MR_Yq
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/** ,5$G0
* Created on 2005-7-12 0]SWyC
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*/ T]wI)
package com.javaeye.common.business; ,7j8+p|},
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import java.io.Serializable; L4Jm8sy{
import java.util.List; Ts
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import org.hibernate.Criteria; Hq}g1?b
import org.hibernate.HibernateException; {KHI(*r;
import org.hibernate.Session; zTcz+3x
import org.hibernate.criterion.DetachedCriteria; 'l^Bb#)"
import org.hibernate.criterion.Projections; h,Hr0^?
import Cw(e7K7&
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org.springframework.orm.hibernate3.HibernateCallback; VF2,(f-*
import rQ*w3F?:
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org.springframework.orm.hibernate3.support.HibernateDaoS U*a#{C7"
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upport; m
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import com.javaeye.common.util.PaginationSupport; 9$$ Ijf
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public abstract class AbstractManager extends XDCm
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HibernateDaoSupport { fsjLD|?|:
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privateboolean cacheQueries = false; %J1'>nI!q
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privateString queryCacheRegion; =v !8i
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publicvoid setCacheQueries(boolean *W}nw$tnBX
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cacheQueries){ >4lA+1JYk
this.cacheQueries = cacheQueries; 0}_1ZU
} U&+lw=
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publicvoid setQueryCacheRegion(String @MH/efW.
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queryCacheRegion){ \o?
this.queryCacheRegion = %[?{H} y
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queryCacheRegion; QUdF`_U7
} ui*CA^ Y
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publicvoid save(finalObject entity){ XKBQH(
getHibernateTemplate().save(entity); h_t<Jl
} 5)K?:7
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publicvoid persist(finalObject entity){ f,0oCBLPO
getHibernateTemplate().save(entity); J@9E20$
}
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publicvoid update(finalObject entity){ k@C]~1
getHibernateTemplate().update(entity); ~ @s$
} 7G8M+i3q/
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publicvoid delete(finalObject entity){ S|v-lJ/I
getHibernateTemplate().delete(entity); ^sVB:?
} uw&'=G6v
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publicObject load(finalClass entity, &AlX).
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finalSerializable id){ >/F,Z%!&q
return getHibernateTemplate().load O!\\m0\e
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(entity, id); ,n?oNU
} VFwp .1oa!
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publicObject get(finalClass entity, 7L&=z$U@m
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finalSerializable id){ -^LEGKN
return getHibernateTemplate().get as6YjE.Yy
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(entity, id); Rm!Iv&{
} lGZ^ 8
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publicList findAll(finalClass entity){ K%A:W
return getHibernateTemplate().find("from {wx!~K
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" + entity.getName()); NrdbXPHceN
} 'Nv*ePz
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publicList findByNamedQuery(finalString Yl#r9TM
@bj3N
namedQuery){ X4U$#uI{
return getHibernateTemplate &8 ~+^P1w
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().findByNamedQuery(namedQuery); -HU5E>xG
} Zg/ra1n
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publicList findByNamedQuery(finalString query, Gt^Fj&^
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finalObject parameter){ 257pO9]
return getHibernateTemplate 2\M^_x$N
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().findByNamedQuery(query, parameter); /MB3w m
} Oozt&* F
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publicList findByNamedQuery(finalString query, tB_GEt2M
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finalObject[] parameters){ s=&&gC1
return getHibernateTemplate c_e2'K:
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().findByNamedQuery(query, parameters); fWKI~/eUY|
} 0?KY9
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publicList find(finalString query){ RjY(MSc
return getHibernateTemplate().find RG9YA&1ce
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(query); eot]VO:
} v&p|9C@
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publicList find(finalString query, finalObject pPSmSWD?
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parameter){ (,wIbwa
return getHibernateTemplate().find LE!xj 0
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(query, parameter); UoAHy%Y<%
} g=)B+SY'
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public PaginationSupport findPageByCriteria #0HZ"n
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(final DetachedCriteria detachedCriteria){ -;NGS
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return findPageByCriteria Q=YIAGK
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); X:N`x
} ~quof>
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public PaginationSupport findPageByCriteria ;Gc,-BDFw
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(final DetachedCriteria detachedCriteria, finalint srzlr-J
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startIndex){ ,7HlYPec
return findPageByCriteria !wbO:py[8>
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(detachedCriteria, PaginationSupport.PAGESIZE, olm0O (9
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startIndex); o >wty3l:
} `!,"">5
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public PaginationSupport findPageByCriteria WK2YHJ*$
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}
(final DetachedCriteria detachedCriteria, finalint V^* ];`^
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pageSize, ttP|}|O
finalint startIndex){ \wjT|z1+Y
return(PaginationSupport) wH?]kV8Q
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getHibernateTemplate().execute(new HibernateCallback(){ B4
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publicObject doInHibernate :9H`O!VF
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(Session session)throws HibernateException { ,=a+;D]'
Criteria criteria = dI(1L~
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detachedCriteria.getExecutableCriteria(session); t6q7w
int totalCount = ]D.}
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((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); 1.H!A@
criteria.setProjection ?v8k& q^q
@>IjfrjV
(null); {Yk20Zn
List items = ebe@.ZVSi
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criteria.setFirstResult(startIndex).setMaxResults <M?#3&5A
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(pageSize).list(); 1!wEXH(
PaginationSupport ps = !#I/be]
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new PaginationSupport(items, totalCount, pageSize, 8@KFln )[
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startIndex); r)]CZ])
return ps; VQ<i$ I
} Q3%#
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}, true); ]3,.g)U*m
} {U '&9_y
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public List findAllByCriteria(final /_OZ1jX
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DetachedCriteria detachedCriteria){ d"6]?
return(List) getHibernateTemplate j4xr1y3^
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().execute(new HibernateCallback(){ <o7#?AcPu
publicObject doInHibernate ([CnYv
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(Session session)throws HibernateException { '#i]SU&*
Criteria criteria = s!/holu
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detachedCriteria.getExecutableCriteria(session); LL[#b2CKa
return criteria.list(); ,V]A63J
} rKQASRF5*
}, true); -Bo~"q
} \_Kt6=
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public int getCountByCriteria(final B+e_Y\Bu
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DetachedCriteria detachedCriteria){ mOgOHb2
Integer count = (Integer) #}!>iFBcH
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getHibernateTemplate().execute(new HibernateCallback(){ ZE8/ m")
publicObject doInHibernate QPe9s[Y
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(Session session)throws HibernateException { ;*-@OLT_K
Criteria criteria = KM5DYy2 A6
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detachedCriteria.getExecutableCriteria(session); ]opW; |{e
return {Bq"$M!Y
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criteria.setProjection(Projections.rowCount xZP >g
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()).uniqueResult(); B)"#/@!bHH
} c{,y{2c]LT
}, true); c8-69hb?
return count.intValue(); xxoHH#a
} !u53 3
} +f
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用户在web层构造查询条件detachedCriteria,和可选的 pkXfsi-Nu
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 d2C[wQF
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PaginationSupport的实例ps。 HPtTv}l
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ps.getItems()得到已分页好的结果集 !F+|Y"c
ps.getIndexes()得到分页索引的数组 8h&oSOkQk,
ps.getTotalCount()得到总结果数 p.rdSv(8'
ps.getStartIndex()当前分页索引 NK7H,V}T
ps.getNextIndex()下一页索引 {PODisl>\D
ps.getPreviousIndex()上一页索引 'v\1:zi
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 MzEm*`<
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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 Z/2,al\
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一下代码重构了。 4Qa@`
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我把原本我的做法也提供出来供大家讨论吧: 2d-TU_JqX
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首先,为了实现分页查询,我封装了一个Page类: 0+T*$=?
java代码: 5f;n<EPy
{ 1+Cw?1d
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/*Created on 2005-4-14*/ h5L=M^z!>
package org.flyware.util.page; 0JmFQ^g(
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/** ]Nnxnp
* @author Joa cC^W2\
* d5>H3D{49
*/ 6sE{{,OGB
publicclass Page { f_imyzP
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/** imply if the page has previous page */ dTL5-@
privateboolean hasPrePage; Qq@G\eRo
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/** imply if the page has next page */ Z{
u a=0
privateboolean hasNextPage; =;3fq-
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/** the number of every page */ *5wu
privateint everyPage; >rP#ukr5
Khe!g1=&X
/** the total page number */ Bcjx>#3?L
privateint totalPage; DEw8*MN
>^OC{~Az
/** the number of current page */ +*n-<x5"
privateint currentPage; GCttXAto
b:(-
/** the begin index of the records by the current A+&xMM2Wj
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query */
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privateint beginIndex; 2iU7 0(H
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/** The default constructor */ HJC(\\~
public Page(){ |w*R8ro_
_oB_YL;,*
} yE\wj
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/** construct the page by everyPage D&ve15wL
* @param everyPage KT.?Xp:z
* */ |T4kqW{
public Page(int everyPage){ Dl&GJ`&:p
this.everyPage = everyPage; gUR]{dq^'
} ~RBrSu)
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/** The whole constructor */ ,zQOZ'^
public Page(boolean hasPrePage, boolean hasNextPage, &6j<c a
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int everyPage, int totalPage, Vi]c%*k
int currentPage, int beginIndex){ 7$k8%lI;>
this.hasPrePage = hasPrePage; -.<k~71
this.hasNextPage = hasNextPage; D%7kBfCb
this.everyPage = everyPage; &48_2Q"{
this.totalPage = totalPage; .la&P,j_L
this.currentPage = currentPage; o\`>c:.
this.beginIndex = beginIndex; C*I(|.i@
} @4!x>q$3
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/** nd{R
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* @return a45ss7
* Returns the beginIndex. l12$l<x&M
*/ Y& ] 8 {
publicint getBeginIndex(){ .1 QgK
return beginIndex; M]HgIL@9#
} p8+/\Ee]B
&s)0z)mR8&
/** O4No0xeWo
* @param beginIndex ~ ~8rI[/
* The beginIndex to set. m=b~i^@
*/ ]]cYLaq(
publicvoid setBeginIndex(int beginIndex){ Ae?e 70bY
this.beginIndex = beginIndex; -qe bQv
} uu%?K@Qq
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/** QMk+RM8U
* @return (_9|w|(
* Returns the currentPage. YCw('i(|
*/ {*/dD`
publicint getCurrentPage(){ 0]x;n+G[q
return currentPage; "L3Xd][
} u8OxD
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/** `ycU-m==
* @param currentPage ~4)Y#IxL
* The currentPage to set. PM4>ThQ
*/ "A]Y~iQ
publicvoid setCurrentPage(int currentPage){ >Wh3MG6
this.currentPage = currentPage; 3ViM ?p
} XLTD;[jO
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/** (BERY
* @return M^H90GN)X
* Returns the everyPage. CtT~0Y|
*/ 00M`%c/
publicint getEveryPage(){ pIVq("&
return everyPage; Qg0vG]
} (L|}`
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/** :HW>9nD.
* @param everyPage 3#Y3Dz`
* The everyPage to set. _
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*/ 0RyFv+
publicvoid setEveryPage(int everyPage){ M^ 5e~y
this.everyPage = everyPage; r] t )x*
} M}!A]@
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/** 9bn2UiJk
* @return Z5>V{o
* Returns the hasNextPage. aqfL0Rg+`
*/ L#j|2H|
publicboolean getHasNextPage(){ 797X71>
return hasNextPage; 9bEM#Hj
} )C}KR`"
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/** =hcPTU-QU
* @param hasNextPage l^,qO3ES
* The hasNextPage to set. l7Lj[d<n
*/ @*_ZoO7{
publicvoid setHasNextPage(boolean hasNextPage){ 8ath45G @
this.hasNextPage = hasNextPage; nx;$dxx_Ws
} (b|#n|~?YL
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/** y#bK,}
* @return .b _? -Fv
* Returns the hasPrePage. M;qb7Mu
*/ @,YlmX}
publicboolean getHasPrePage(){ cno;>[$
return hasPrePage; O!];_q/
} L *{QjH
c
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/** y.fs,!|%@
* @param hasPrePage A^cU$V%?W
* The hasPrePage to set. Oc^m_U8>^
*/ kdBV1E+:C
publicvoid setHasPrePage(boolean hasPrePage){ q\U4n[Zk
this.hasPrePage = hasPrePage; `A"Q3sf%
} ?C~X@sq
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/** 3]_qj*V
* @return Returns the totalPage. Ivjw<XP6K
* 5&G
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*/ lJ'trYaq7
publicint getTotalPage(){ t]r7cA
return totalPage; QnP{$rT
} !Z-9tYO
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/**
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* @param totalPage ,{pGP#
* The totalPage to set. g#Mv&tU
*/ +h|K[=l\
publicvoid setTotalPage(int totalPage){ k}-]W@UCa?
this.totalPage = totalPage; 8Y xhd
.
} gjQ=8&i
Y!;gQeC
} 9,w}Xe=C
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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 E;xMPK$
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个PageUtil,负责对Page对象进行构造: v8>!Gft
java代码: 5pB^Y MP
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/*Created on 2005-4-14*/ :cEd [Jm9
package org.flyware.util.page; D7M0NEY
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import org.apache.commons.logging.Log; r7RU"H:j8
import org.apache.commons.logging.LogFactory; xkF$D:sP
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/** g>UBZA4
* @author Joa xcw%RUC-
* y{YXf!AS
*/
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publicclass PageUtil { " \`BPN
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privatestaticfinal Log logger = LogFactory.getLog Mp^^!AP 9
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(PageUtil.class); DgC3>
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/** r>E\Cco
* Use the origin page to create a new page \>4v?\8o
* @param page BXNI(7xi
* @param totalRecords ^WmGo]<B_
* @return
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*/ C2CYIok$&
publicstatic Page createPage(Page page, int sKe,
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totalRecords){ ~5FS|[1L
return createPage(page.getEveryPage(), txj wZ_p
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page.getCurrentPage(), totalRecords); u)tHOV>&
} lr-12-D%-
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/** AGl|>f)
* the basic page utils not including exception Jq=00fcT+
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handler }A^1q5
* @param everyPage yJF 2
* @param currentPage 8.*\+nH
* @param totalRecords $7msL#E7
* @return page #DQX<:u
*/ B jH ~Ml2
publicstatic Page createPage(int everyPage, int \Y51KB\
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currentPage, int totalRecords){ X!,#'&p&
everyPage = getEveryPage(everyPage); ->#y(}
currentPage = getCurrentPage(currentPage); nu#aa#ex>
int beginIndex = getBeginIndex(everyPage, CWE Ejl
8T8pAs0
p
currentPage); H(X+.R,Thp
int totalPage = getTotalPage(everyPage, l5{(z;xM
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totalRecords); ^;0~6uBEJr
boolean hasNextPage = hasNextPage(currentPage, \Ku9"x
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totalPage); @`w'
boolean hasPrePage = hasPrePage(currentPage); HF*j`}
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returnnew Page(hasPrePage, hasNextPage, B0-4ZT
everyPage, totalPage, % MfGVx}nG
currentPage, cEDDO&u
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beginIndex); <bEN8b
} )m|X;eEo
&/B2)l6a
privatestaticint getEveryPage(int everyPage){ N,WI{*
return everyPage == 0 ? 10 : everyPage; 8vz_~p9%j
} F,'^se4&
c*y$bf<
privatestaticint getCurrentPage(int currentPage){ :N^@a-
return currentPage == 0 ? 1 : currentPage; PY^^^01P
} %k/
k]:s
tb-OKZq
privatestaticint getBeginIndex(int everyPage, int uvu**s
>u BV
currentPage){ 5?V?
return(currentPage - 1) * everyPage; s=H/b$v
} A2g"=x[1@K
D%c7JK
privatestaticint getTotalPage(int everyPage, int naec"Kut
OYqYI!N/
totalRecords){ v$gMLu=
int totalPage = 0; R$!;J?SS
f_i"/xC-/
if(totalRecords % everyPage == 0) H j5WJ{p.
totalPage = totalRecords / everyPage; ;kyL>mV{
else xJ[k#?T'
totalPage = totalRecords / everyPage + 1 ; ^D W#
GL;x:2XA
return totalPage; %nDPM? aO
} G+#| )V
.oi}SG
privatestaticboolean hasPrePage(int currentPage){ egxJ3.
return currentPage == 1 ? false : true; ps!5HZ2:
} f_re"d 3u
WuP([8
privatestaticboolean hasNextPage(int currentPage, !LHzY(
$L<_uqSk
int totalPage){ Y^c,mK^
return currentPage == totalPage || totalPage == [p( #WM:
?BHWzo!
0 ? false : true; ]v^`+s}3
} c:h.J4mv
DJ
mQZ+{2
.gM>FUH3L
} 5I8FD".i
}Ke}rM<
u/!mN2{Rd
;G%wc!
7U{b+=,wK
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。 L5zG0mC8
sl^s9kx;C$
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 }QWTPRn
gq/ePSa
做法如下: @Q$/eL
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zgq_0w~X
z~}StCH(
的信息,和一个结果集List: wQdW
lon
java代码: P[#WHbn
T4H oSei
l# !@{ <
/*Created on 2005-6-13*/ p(x1D]#Z[
package com.adt.bo; ^EuyvftZ
ArmL,
import java.util.List; (v'lb!j^#
_} X`t8L h
import org.flyware.util.page.Page; _ntW}})K
< o'7{
/** Y&05
*b"
* @author Joa 5QL9w3L
*/ t5X^(@q4N
publicclass Result { W3o}.|]
WfTdD.Xx
private Page page; ltr;pc*)
/ie3H,2
private List content; <_sT]?N#
t0asW5f
/** 9$P l'>5
* The default constructor Yyo9{4v+p{
*/ S"KTL *9D
public Result(){ :S+U}Sm[
super(); }*}`)rj,
} (;2J(GZ:$U
[BZ(p
/** ZTBFV/{
* The constructor using fields 3ciVjH>i
* $p6Xa;j$ 9
* @param page zy/tQGTr@
* @param content $MJDB
*/ tls6rto
public Result(Page page, List content){ h[`Op#^x3
this.page = page; yz2oS|0 '
this.content = content; 7].IT(
} H`6Jq?\
8F\Msx
/** ^cmP
* @return Returns the content. j=jrzG+`
*/ VrGb;L'[
publicList getContent(){ [;CqvD<S
return content; RkH oT^
} U*R~w5W.[
R:IS4AaS
/** QRmQ>
* @return Returns the page. 9y|&T
*/ Yqhz(&*)
public Page getPage(){ i8[Y{a*
return page; U9p.Dh~)vG
} hq8/`u
YF
`1d`9AS2g
/** !qGx(D{\
* @param content l6DIsR
* The content to set. *6x^w%=A
*/ b5 C}K
public void setContent(List content){ iJKm27 ">
this.content = content; X @jYQ.
} l[\,*C
Y %D*O
/** 6!Ji>h.Ak
* @param page :-WCW);N
* The page to set. rNzhP*Fw
*/ [@)z $W
publicvoid setPage(Page page){ ,a_{ Y+
this.page = page; ~CdseSo9
} ND9>`I5
} GoVPo'
Y./}zCT
=|V]8 tN
>Hzb0N!VJ
*Qwhi&k
2. 编写业务逻辑接口,并实现它(UserManager, `"=L
w@$o
UserManagerImpl) %b%<g%@i
java代码: |VR5Q(d
>iWf7-:
2l/5i]Tq
/*Created on 2005-7-15*/ AXv;r<
package com.adt.service; ?gMrcc/{
2gR_1*|
import net.sf.hibernate.HibernateException; pW^ ?g|_}
M*@aA
XM
import org.flyware.util.page.Page; W]Tt8
Q;,3W+(
import com.adt.bo.Result; Jq<`j<'9
}xlmsOHuI
/** 7{6.
* @author Joa n zrCOMld
*/ oUKbzr/C
publicinterface UserManager { ggsi`Z{j?
M9jo<+
public Result listUser(Page page)throws YM*6W?
HYnq x>L ~
HibernateException; }
9s
i\4"FO?v
} R9-JjG2v
:ItW|
pV|?dQ
uW'4
Kt
gN'i+mQcu
java代码: .%b_3s".
=(5GU<}
*vE C,)
/*Created on 2005-7-15*/ sP8&p*TJF
package com.adt.service.impl; RGuHXf
3U.qN0]
import java.util.List; M`fXH 3D
YaT+BRh?
import net.sf.hibernate.HibernateException; EI+/%.,
dq/?&X
import org.flyware.util.page.Page; ]3u'Qv}o
import org.flyware.util.page.PageUtil; T`{MQ:s
9<c4y4#y
import com.adt.bo.Result; ?q }wl\"8
import com.adt.dao.UserDAO; rw0lXs#K<E
import com.adt.exception.ObjectNotFoundException; R
eu
J=|F
import com.adt.service.UserManager; Kf^F#dA
'#::ba[9w
/** Rj;e82%%N
* @author Joa !:[n3.vm
*/ VCRv(Ek
publicclass UserManagerImpl implements UserManager { :v8j3=
:Y~fPke
private UserDAO userDAO; :C_\.pA
8%>
Ls
/** %Mz(G-I.\
* @param userDAO The userDAO to set. E(>RmPP=7
*/ 7bCTR2e\@w
publicvoid setUserDAO(UserDAO userDAO){ "JKrbgN@;L
this.userDAO = userDAO; xSug-
} ,8cw jS2E
a[[u>oHyd
/* (non-Javadoc) (]vHW+'
* @see com.adt.service.UserManager#listUser 1E=%:? d
Xc"S"a^\%
(org.flyware.util.page.Page) K{t7_i#tv
*/ K({+3vK
public Result listUser(Page page)throws l7
j3;Ly
KYu3dC'/,&
HibernateException, ObjectNotFoundException { N9Y,%lQ|B8
int totalRecords = userDAO.getUserCount(); B/c_pRl;
if(totalRecords == 0) |wQ|h$|
throw new ObjectNotFoundException M
g1E1kXe
W5<1@
("userNotExist"); e(O"V3wq*6
page = PageUtil.createPage(page, totalRecords); <RKh%4#~
List users = userDAO.getUserByPage(page); w%GEOIj}
returnnew Result(page, users); YFy5>*W
} ]SFB_5Gb
/E@LnKe
} .3Jggp
c{ +Y$
'dDd9
QA+qFP
w*e O9k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %1 9TJn%J$
_6;T
/_R=
询,接下来编写UserDAO的代码: K!lGo3n]
3. UserDAO 和 UserDAOImpl: Z6
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java代码: &D\~-fOGb
vA10'Gx'
V)^nVD)e
/*Created on 2005-7-15*/ Q>cLGdzO
package com.adt.dao; L!|c: 8
5lu620o
import java.util.List; d/k&f5
Q4JwX=ZVj
import org.flyware.util.page.Page; _8)9I?jH
=1!wep"
import net.sf.hibernate.HibernateException; ~^2Y*|{)
<VS\z(K
/** l'fUa
* @author Joa DI'wZySS^
*/ 3l0x~
publicinterface UserDAO extends BaseDAO { FZ
DC?
P
1X8
publicList getUserByName(String name)throws {a- p/\U
~Y<x-)R
HibernateException; x>8=CiUE
"<SK=W
publicint getUserCount()throws HibernateException; (y7U}Sb'
s(q\!\FS
publicList getUserByPage(Page page)throws zHw[`"[
dW
Y0
HibernateException; RcitW;{|Kg
-z)I;R
} I9h?Z&n5
<\|f;7/
{x40W0
CS"2Sd 1`
O:"gJ4D
java代码: P^#<h"Ht
3de<H=H'
Ouc=4'$-
/*Created on 2005-7-15*/ }:P/eY
package com.adt.dao.impl; c~[L;_
]e@'9`G-'
import java.util.List; "yxIaTZu
tbrjTeC
import org.flyware.util.page.Page;
3#}5dO
-&oJ@Aa
import net.sf.hibernate.HibernateException; yxh8sAZ
import net.sf.hibernate.Query; RNE})B
l 3bo
import com.adt.dao.UserDAO; ; 6Js
xG@zy4
/** 7Rqjf6kX`O
* @author Joa v@TP_Ka
*/ Ufd{.o[{-
public class UserDAOImpl extends BaseDAOHibernateImpl k;/U6,LQ*
zL$$G,
implements UserDAO { UmZ#Cm
avrf]raM|
/* (non-Javadoc) @U08v_,
* @see com.adt.dao.UserDAO#getUserByName ,E2Tw-%
}a6tG
(java.lang.String) |fkz=*rn
*/ Z;`ts/?SY]
publicList getUserByName(String name)throws e$}x;&c Q
%/NB263Db
HibernateException { Rqu_[M
String querySentence = "FROM user in class t$m~O?I
=S7Xj`/
com.adt.po.User WHERE user.name=:name"; 6O uB}*
Query query = getSession().createQuery Li)rs<IX;m
*f{\ze@5=
(querySentence); yU]NgG=z:-
query.setParameter("name", name); ?_*X\En*3
return query.list(); &6V[@gmD
} ;5QdT{$H
Ib3n%AG
/* (non-Javadoc) LldZ"%P
* @see com.adt.dao.UserDAO#getUserCount() ZqH.$nXP
*/ q9 !)YP+w
publicint getUserCount()throws HibernateException { >qkZn7C
int count = 0; Hz39v44
String querySentence = "SELECT count(*) FROM =?hGa;/rb
?Co)7}N
user in class com.adt.po.User"; (Ubz@s^
Query query = getSession().createQuery foO/Yc
G+&ug`0]5
(querySentence); =Ji+GJ<,9
count = ((Integer)query.iterate().next
\~u7 k
9n\:grW
()).intValue(); l12Pj02 w
return count; 3[`/rg,
} &/)2P#u
/o@6?UH
/* (non-Javadoc) zl8O @g
* @see com.adt.dao.UserDAO#getUserByPage R]L$Ld< ij
hc#LniR3$
(org.flyware.util.page.Page) 3azyqpwU$
*/ "QCtF55X&
publicList getUserByPage(Page page)throws #yPQt!
&!Sq6<!v2
HibernateException { FO[x
c;
String querySentence = "FROM user in class ]/31@RT
/qf(5Bm
com.adt.po.User"; -;T!d
Query query = getSession().createQuery ",&^ f
&|6 A
8,
(querySentence); Vz4/u|gt
query.setFirstResult(page.getBeginIndex()) ,_+Gb
.setMaxResults(page.getEveryPage()); NA@<v{z
return query.list(); jTSN`R9@
} b3j?@31AD
4th*=ku
} ]Q8[,HTG
[2~^~K
(%N=7?
}o9fpo|
z?Hi
u6c-
至此,一个完整的分页程序完成。前台的只需要调用 _mBFmXHHS$
z8VcV*6
userManager.listUser(page)即可得到一个Page对象和结果集对象 nr*nX
!!KA9mP
的综合体,而传入的参数page对象则可以由前台传入,如果用 \t=ls
%?sPKOh3N}
webwork,甚至可以直接在配置文件中指定。 d+m}Z>iQ1O
3P,
ul*e
下面给出一个webwork调用示例: W%&gvZre.
java代码: 0pfgE=9
i#pBzJ
eE=}^6)(*
/*Created on 2005-6-17*/ OTy{:ID
package com.adt.action.user; UR{OrNg*
Z=KHsMnB
import java.util.List; y"I8^CA
uge~*S
import org.apache.commons.logging.Log; $*\GZ$y>
import org.apache.commons.logging.LogFactory; @A.7`*i_
import org.flyware.util.page.Page; #qnK nxD
ow<z @^ 3'
import com.adt.bo.Result; YqQAogyh
import com.adt.service.UserService; [gkOwU=?
import com.opensymphony.xwork.Action; nSSj&q- O
;5dA
/** a#pM9n~a
* @author Joa y 1I(^<qO=
*/ O$*\JL
publicclass ListUser implementsAction{ hy}n&h
B]nu \!
privatestaticfinal Log logger = LogFactory.getLog 'Szk!,_
l0&U7gr
(ListUser.class); yhsbso,5 a
b/]@G05>>
private UserService userService; S-7ryHH*0
^ZD0rp(l
private Page page; xXQW|#X\
p!o+8Xz5
privateList users; m\"X%Y#
ba"_!D1
/* .a_xQ]eQ
* (non-Javadoc) (L
8V)1N
* 8(@Y@`/
* @see com.opensymphony.xwork.Action#execute() [ApAd
*/ knABlU
publicString execute()throwsException{ &eIwlynm
Result result = userService.listUser(page); d-ML[^G
page = result.getPage(); $.Qu55=z<
users = result.getContent(); /zTx+U.\I
return SUCCESS; , 9"A"p*R
} {SJnPr3R
~|R/w%*C
/** ( jtkY_
* @return Returns the page. +V,Ld&r
*/ j=V2~
xA6
public Page getPage(){ 9oA-Swc[
return page; r.10b]b
} "*oN~&flc
FZ@8&T
/** yiAusl;
* @return Returns the users. ?t"bF :!
*/ e=4k|8 G
publicList getUsers(){ *rmwTD"
return users; e*/ya 8p?
} :qxd
s>Xm
tRzo}_+N
/** .9u,54t
* @param page ,}HnS)+
* The page to set. V1>>]]PS
*/ .ta*M{t
publicvoid setPage(Page page){ I3D#wXW
this.page = page; s[tFaB 1
} O\[Td
+Heen3
/** 7).zed^
* @param users gA~faje
* The users to set. d){Al(/
*/ %{K6
publicvoid setUsers(List users){ V[BlT|t
this.users = users; pgU4>tyD
} "Qxn}$6-
sow/JLlbC
/** m[!AOln)
* @param userService m8ydX6~max
* The userService to set. Ea2&7
*/ {r?qI
publicvoid setUserService(UserService userService){ +6v;(] y
this.userService = userService; k%v/&ojI
}
g+iV0bbT
} tf@x}
SsF
5+=A
q;a#?Du o
Lu?)Rya
/,Sd
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, G$HLta
3((53@s98
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 DLrG-C33
G
]mX+?
么只需要: MB,P#7|
java代码: %C8fv|@:f
d]ZC8<`w
SKSAriS~
<?xml version="1.0"?> V\K
m% vP
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $^=jPk]+
9Ir~X|}\iL
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _jrA?pY
/-{O\7-D
1.0.dtd"> EB2^]?
#4_O;]{'
<xwork> &lh_-@Xz
b6!Q!:GO&
<package name="user" extends="webwork- wAYzR$i
_"!{7e`Z
interceptors"> Fm$n@RbX
I"Q9W|J_&
<!-- The default interceptor stack name ^dUfTG9{
fteyG$-s
--> S?nNZW\6[
<default-interceptor-ref 0J:U\S
}`9fZK{. @
name="myDefaultWebStack"/> dVVvG]
>b4YbLkI#
<action name="listUser" +<!)k?
*]:G7SW{
class="com.adt.action.user.ListUser"> >^T,U0T])
<param 7:VEM;[d
RRI>bh]
name="page.everyPage">10</param> (ciGLfNG
<result _yxe2[TD
4lY&=_K[)
name="success">/user/user_list.jsp</result> Owh*KY:
</action> PK-}Ldj
o}mhy`}
</package> } `>J6y9
lrmt)BLoh
</xwork> mq{$9@3
} Jdh^t .
(!_X:+0_
(EOec5qXU
2[8fFo>
_cxm}*}\#
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 U9@t?j_#X{
iJCY /*C}
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 , `[Z`SUk`
kH>vD =q>
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 P;L)1 g
-~(0O
%67G]?EXB
lnS\5J
@o4z3Q@
我写的一个用于分页的类,用了泛型了,hoho D% v:PYf
r6oX6.c
java代码: v|4STR
E,*JPK-A x
DJ1XNpm
package com.intokr.util; ] 689 Q%D
r+[#%%}ea
import java.util.List; DU/9/ I?~
c]s(u+i
/** wc6
E-rB
* 用于分页的类<br> f"ZqA'KB#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> K)Df}fVOc
* *tTP8ZCQ[
* @version 0.01 YiIddQ
* @author cheng
nR,Qm=;
*/ ]/aRc=Gn
public class Paginator<E> { M&|sR+$^
privateint count = 0; // 总记录数 'WKu0Yi^'
privateint p = 1; // 页编号 ys&"r":I
privateint num = 20; // 每页的记录数 q5:0&:m$4$
privateList<E> results = null; // 结果 rt5oRf:wY
K:>NGGY8r
/** (ZE%tbm2
* 结果总数 &57qjA,8<
*/ .x)>f
publicint getCount(){ oJlN.Q#u&
return count; >Jm-2W5J
} =,&u_>Dp
E@5zd@[
publicvoid setCount(int count){ cwH,l$
this.count = count; K?h[.`}
} w$DG=!
D 7Gd%
/** 4'+d"Ok
* 本结果所在的页码,从1开始 >QYh}Z-/%
* vbr~<JT=
* @return Returns the pageNo. 89*S?C1
*/ w"fCI13
publicint getP(){ 9>A-$a4R>
return p; 4u3 \xR?w6
} httls>:xB|
^z[_U}N\}
/** 2LCc
* if(p<=0) p=1 [WcS[](ob
* QDIsC
* @param p 7ZF}0K$^B
*/ 3M}AxE u
publicvoid setP(int p){ !d:tIu{)
if(p <= 0) Tx y]"_
p = 1; 1P5*wNF
this.p = p; hWe}'L-
} k
TF z_*6.
1t0bUf;(M
/** w0#%AK
* 每页记录数量 dj?G.-
*/ y.jS{r".
publicint getNum(){ b2a'KczV
return num;
]a78tTi
} s ;48v
MNkKy(Za
/** 929#Q#TT
* if(num<1) num=1 \V._Z>]
*/ 'g. :MQ8
publicvoid setNum(int num){ Xyb8u})p'
if(num < 1) ^/G?QR
num = 1; ^%-NPo<
this.num = num; Jm?l59bv
v
} Sq?,C&LsA
w(aUEWYL
/** }%_qx|(P|t
* 获得总页数 ymHKcQ
*/ |d5ggf.w
publicint getPageNum(){ 2q+la|1Cr
return(count - 1) / num + 1; 2q12yY f
} x<8\-
Lt>?y&CcQ
/** x]H3Y3
* 获得本页的开始编号,为 (p-1)*num+1 8a7YHUL<3i
*/ 8^i[j\Y;6
publicint getStart(){ Xu6jHJ@ x
return(p - 1) * num + 1; QDP-E[
} XnD0eua#
k9cK bf@
/** =1O?jrl~q
* @return Returns the results. Bhj:9%`
*/ 9 _eS`,'
publicList<E> getResults(){ X#VEA=4{
return results; Ec+22X
} OthG7+eF
#uB[&GG}W
public void setResults(List<E> results){ @sN^BX`z
this.results = results; X@cSP7b
} ;
/=L
YRXK@'[=
public String toString(){ cY{I:MA+h@
StringBuilder buff = new StringBuilder #0(fOHPQ
%t q&
(); [
ynuj3G
V
buff.append("{"); Ohc^d"[7
buff.append("count:").append(count); ^[0"vtb
buff.append(",p:").append(p); 0Qt~K#mr/
buff.append(",nump:").append(num); |l$
u<3
buff.append(",results:").append 1p~5h(jI
D_Guc8*
(results); _n7%df
buff.append("}"); r-*l1([eW
return buff.toString(); Trpgx
} nYhp`!W4;
pVY4q0@
} vpi l$Uq
ZH!;z-R
("b*? : B