Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1!4-M$-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fi.[a8w:W
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 l#;DO9
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 `f~\d.*U
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分页支持类: lPywrTG0
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java代码: +=Q/'g
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package com.javaeye.common.util; 7ZsBYP8%
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import java.util.List; eM$NVpS3
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publicclass PaginationSupport { bkvm-$/
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publicfinalstaticint PAGESIZE = 30; 4|#@41\ B
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privateint pageSize = PAGESIZE; ZHWxU
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privateList items; (5Z*m<]c
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privateint totalCount; 3iI 4yg
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privateint[] indexes = newint[0]; ^z%ShmM&LZ
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privateint startIndex = 0; FZ0wtS2
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public PaginationSupport(List items, int P~H?[
;
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totalCount){ MN.h,^b
setPageSize(PAGESIZE); M:9
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setTotalCount(totalCount); Us.")GiHE
setItems(items); fQkfU;5
setStartIndex(0); l[AQyR1+/
} ;tZ;C(;<
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public PaginationSupport(List items, int b 5u8j
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totalCount, int startIndex){ Wz%b,!
setPageSize(PAGESIZE); bl8EzO
setTotalCount(totalCount); /~O>He
setItems(items); V8Fp1?E9S
setStartIndex(startIndex); D["~G v
} %lbDcEsf9
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public PaginationSupport(List items, int `Nnaw+<]
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totalCount, int pageSize, int startIndex){ $\w<.)"#
setPageSize(pageSize); OtVRhR3>
setTotalCount(totalCount); z[0+9=<Y
setItems(items); b5@sG^
setStartIndex(startIndex); v/m} {&K
} vR)f'+_Nz
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publicList getItems(){ q9h3/uTv
return items; J2BCaAwEP,
} 2&,jO+BqE@
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publicvoid setItems(List items){ O)jpnNz
this.items = items; 2I|`j^
} 4!</JZX~$
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publicint getPageSize(){ 6${=N}3Kw
return pageSize; !2o1c
} %6%~`((4
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publicvoid setPageSize(int pageSize){ VL?sfG0
this.pageSize = pageSize; d$H
} `B A'a" $
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publicint getTotalCount(){ ..K@'*u
return totalCount; JqmxS*_P
} X 3dXRDB'
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publicvoid setTotalCount(int totalCount){ P2!+ZJ&
if(totalCount > 0){ L7`=ec<
this.totalCount = totalCount; /=(PMoZu
int count = totalCount / Z^[
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pageSize; (6crWw{3
if(totalCount % pageSize > 0) !0Mx Bem
count++; TFAd
indexes = newint[count]; M/mm2?4
for(int i = 0; i < count; i++){ .}c&"L;W
indexes = pageSize * f|'0FI
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} `9*
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}else{ B{lj.S`mB
this.totalCount = 0; E Xxv
} QMhvyzkS
} }WV}in0
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publicint[] getIndexes(){ 9Rm\@E
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return indexes; 67g"8R#.V
} 0g`$Dap
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publicvoid setIndexes(int[] indexes){ Q3I^(Ll"L
this.indexes = indexes; &~aS24c
} ,x=S)t
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publicint getStartIndex(){ 2j;9USZ
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return startIndex; zMXQfR
} ~+)>D7
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publicvoid setStartIndex(int startIndex){ 3`TD>6rs
if(totalCount <= 0) q|g>;_
this.startIndex = 0; l86gs6>
elseif(startIndex >= totalCount) 7tP%tp
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this.startIndex = indexes 8Drz
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[indexes.length - 1]; d.0K~M
elseif(startIndex < 0) RG.wu6Av
this.startIndex = 0; yu>o7ie+;Y
else{ }0IeKpu5
this.startIndex = indexes 1{AK=H')
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[startIndex / pageSize]; ri%j*Kn
} U38~m}c
} t$e' [;w
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publicint getNextIndex(){ al" =ld(
int nextIndex = getStartIndex() + rS!M0Hq>t
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pageSize; 1Ror1%Q"?
if(nextIndex >= totalCount) DF>3)oTF
return getStartIndex(); SLW|)Q24
else G*f\
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return nextIndex; }P'c8$
} 1,(WS
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publicint getPreviousIndex(){ ~1&WR`U
int previousIndex = getStartIndex() - 8'"=y}]H~
p ,.6sk
pageSize; T#<Q[h=
if(previousIndex < 0) 5eiKMKW[
return0; nb.|^O?
else 3
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return previousIndex; $XI.`L *g
} jU-aa+
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} UqD ]@s`
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抽象业务类 9a]{|M9
java代码: Wu" 1M^a
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/** 6e8 gFQ"w2
* Created on 2005-7-12 -xG6J.S
*/ Bi2 c5[3
package com.javaeye.common.business; G
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import java.io.Serializable; wX5q=I
import java.util.List; !S%0#d2
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import org.hibernate.Criteria; ~yt 7L,OQ
import org.hibernate.HibernateException; qW`?,N)r
import org.hibernate.Session; T%;V_iW-
import org.hibernate.criterion.DetachedCriteria; nEUUD3a
import org.hibernate.criterion.Projections; 'J$@~P
import T(qTipq0
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org.springframework.orm.hibernate3.HibernateCallback; q^:VF()d_z
import )Gm9x]SVl
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org.springframework.orm.hibernate3.support.HibernateDaoS $H)QUFyC
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upport; L+*:VP6WD
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import com.javaeye.common.util.PaginationSupport; Vef!5]t5
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public abstract class AbstractManager extends x5CMP%}d
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HibernateDaoSupport { jo^c>ur
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privateboolean cacheQueries = false; R*!s'R
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privateString queryCacheRegion; ZSs@9ej
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publicvoid setCacheQueries(boolean O5aXa_A_u
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cacheQueries){ 4y#XX[2Wj
this.cacheQueries = cacheQueries; EK5$z>k>m
} W7Y@]QMX
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publicvoid setQueryCacheRegion(String .$H"j>
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queryCacheRegion){ |iI
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this.queryCacheRegion = 14"57Jt8
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queryCacheRegion; Ix6\5}.c 9
} "a=Hr4C*r
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publicvoid save(finalObject entity){ p #{y9s4h
getHibernateTemplate().save(entity); swxX3GR
} 1f<R,>
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publicvoid persist(finalObject entity){ SDC'S]{ew
getHibernateTemplate().save(entity); v2 E <~/|
} D;NL*4zt
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publicvoid update(finalObject entity){ *!ng)3#
getHibernateTemplate().update(entity); Q"ZpT
} e.skE>&
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publicvoid delete(finalObject entity){ F_(~b
getHibernateTemplate().delete(entity); Hf@4p'
} mf3,V|>[\
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publicObject load(finalClass entity, `hZh}K^
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finalSerializable id){ @<{%r
return getHibernateTemplate().load D>[Sib/@
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(entity, id); =`QYy-b X
} mmbe.$73
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publicObject get(finalClass entity, pX{wEc6}
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finalSerializable id){ j(Lz& *4
return getHibernateTemplate().get ?W{+[OXs
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(entity, id); }q`9U!v
} dI
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publicList findAll(finalClass entity){ (<r)xkn
return getHibernateTemplate().find("from XZb=;tYo
["<Xh0_
" + entity.getName()); V!+iq*Z|=
} ()IZ7#kL?
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publicList findByNamedQuery(finalString n2bhCd]j<b
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namedQuery){ AQUAQZc
return getHibernateTemplate Q-'j131[
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().findByNamedQuery(namedQuery); B=TUZ)
} @W>@6E
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publicList findByNamedQuery(finalString query, Qc3d<{7\~
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finalObject parameter){ Ze~P6
return getHibernateTemplate 9?H$0xZV
\{ @m
().findByNamedQuery(query, parameter); +PjTT6
} Xx{| [2`
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publicList findByNamedQuery(finalString query, q*UHzE:LI
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finalObject[] parameters){ \Nt
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return getHibernateTemplate reN\|?0{
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().findByNamedQuery(query, parameters); bg i_QB#k\
} k9}8xpH
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publicList find(finalString query){ m"n74cxS
return getHibernateTemplate().find %]_: \!
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(query); $Y|OGZH8E
} x"Ky_P~
;
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publicList find(finalString query, finalObject w0_P9g:
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parameter){ [f_^BU&
return getHibernateTemplate().find e"t0 rScA
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(query, parameter); eP @#I^_
} LL#REK|lm8
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public PaginationSupport findPageByCriteria $H@SXx
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(final DetachedCriteria detachedCriteria){ [A7TSN
return findPageByCriteria IE`3I#v
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }=/zG!+
} ,ErfTg&^
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public PaginationSupport findPageByCriteria ddfGR/1X
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(final DetachedCriteria detachedCriteria, finalint YCbvCw$Ob
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startIndex){ =x8[%+
return findPageByCriteria =\O#F88ui
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(detachedCriteria, PaginationSupport.PAGESIZE, I_r@Y:5{
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startIndex); duG3-E
} k_7m[o
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public PaginationSupport findPageByCriteria spV7\Gs.@
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(final DetachedCriteria detachedCriteria, finalint .^wpfS
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pageSize, |{ N{VK
finalint startIndex){ Uj(0M;#%o+
return(PaginationSupport) ZM.'W}J{*
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getHibernateTemplate().execute(new HibernateCallback(){ <,M"kF:
publicObject doInHibernate f;{Q ~
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(Session session)throws HibernateException { aJ+V]WmA
Criteria criteria = {XOl &
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detachedCriteria.getExecutableCriteria(session); hp~q!Q1=
int totalCount = OXEEpoU?V
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((Integer) criteria.setProjection(Projections.rowCount Y*NzY*V\
(.4lsKN<
()).uniqueResult()).intValue(); h$02#(RHJ
criteria.setProjection ?@'&<o0p#
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(null); Hm2Y%
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List items = q^aDZzx,z
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criteria.setFirstResult(startIndex).setMaxResults gA2Wo+\^bq
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(pageSize).list(); K?uZIDo
PaginationSupport ps = jri"# H
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new PaginationSupport(items, totalCount, pageSize, X!]v4ma`
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startIndex); y#GHmHeh
return ps; {:1j>4m2
} ,#)d
}, true); G=:/v
} P6v ANL-B
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public List findAllByCriteria(final &r1(1<
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DetachedCriteria detachedCriteria){ 83vMj$P
return(List) getHibernateTemplate XKWq{,Ks
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().execute(new HibernateCallback(){ F rckA
publicObject doInHibernate uBlPwb,V
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(Session session)throws HibernateException { ;%e)t[5
Criteria criteria = D4L&6[W
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detachedCriteria.getExecutableCriteria(session); tkj-.~@g0'
return criteria.list(); "Vp
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} yT7$6x
}, true); k'o[iKlu
} 8US#SI'x
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public int getCountByCriteria(final dxX`\{E
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DetachedCriteria detachedCriteria){ yNI0Do
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Integer count = (Integer) =z'(FP5!0
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getHibernateTemplate().execute(new HibernateCallback(){ /yI4;:/
publicObject doInHibernate @62,.\F
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(Session session)throws HibernateException { P73GH
Criteria criteria = b?}mQ!
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detachedCriteria.getExecutableCriteria(session); +9Tc.3vQ
return 9S%5Z>
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criteria.setProjection(Projections.rowCount l 2Sar1~1
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()).uniqueResult(); 'ZF6 Z9
} V?Jy
}, true); $S#Z>d*1!
return count.intValue(); KqGb+N-@
} gy.UTAs
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} LSC[S:
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用户在web层构造查询条件detachedCriteria,和可选的 MH.+pqIv^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 =>
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PaginationSupport的实例ps。 kPX+n+$
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ps.getItems()得到已分页好的结果集 U6&`s%mIa
ps.getIndexes()得到分页索引的数组 )gdeFA V
ps.getTotalCount()得到总结果数 hju^x8
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ps.getStartIndex()当前分页索引 JK!(\Ae.
ps.getNextIndex()下一页索引 _WZx].|A=
ps.getPreviousIndex()上一页索引 X~r9yl>
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 eke[{%L
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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 "&={E{pQ
Ge2Klyi
一下代码重构了。 5sJ>+Rg
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我把原本我的做法也提供出来供大家讨论吧: rnK]3Ust
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首先,为了实现分页查询,我封装了一个Page类: -PPwX~;!
java代码: l!,tssQ
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/*Created on 2005-4-14*/ Y~}MfRE3z
package org.flyware.util.page; Tr?p/9.m
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/** V48_aL
* @author Joa s&E,$|80
* 7rdmj[vu
*/ |m-N5$\IC
publicclass Page { XCI
lR %#R
/** imply if the page has previous page */ AZ!/{1 Az
privateboolean hasPrePage; b:S$oE
#2^0z`-\_z
/** imply if the page has next page */ &oG>Rqkm
privateboolean hasNextPage; Osqk#Oh
@K]`!=vUk
/** the number of every page */ +t,b/K(?]
privateint everyPage; u{4P)DIQ
C|]c#X2t3
/** the total page number */ 4pL'c@'
privateint totalPage; HAH\#WE
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/** the number of current page */ oZ2:%
privateint currentPage; [k
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/** the begin index of the records by the current ]+e
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query */ Z RjM^
d;
privateint beginIndex; x;W!sO@$
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/** The default constructor */ . gy:Pl]w
public Page(){ sNx_9pJs4
e;vI XJE
} Py*WHHO
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/** construct the page by everyPage QuS=^,]
* @param everyPage @|(cr: (=H
* */ X8tPn_`x
public Page(int everyPage){ wp~}1]g
this.everyPage = everyPage; 4]1/{</B|
} Ihf>FMl:
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/** The whole constructor */ #bt z94/~O
public Page(boolean hasPrePage, boolean hasNextPage, JcRxNH
)<"
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int everyPage, int totalPage, x6K_!L*Fx]
int currentPage, int beginIndex){ T4W20dxL7
this.hasPrePage = hasPrePage; NzZ(Nz5
this.hasNextPage = hasNextPage; |~A*?6:@
this.everyPage = everyPage; v^eAQoFLhN
this.totalPage = totalPage; ubB1a_7
this.currentPage = currentPage; Gw)y<h
this.beginIndex = beginIndex; L/fXP@u
} 5%D`y|
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/** 7y^)n<'co
* @return O$z"`'&j#
* Returns the beginIndex. ,%Z&*/*Oh
*/ Sck!w 3
publicint getBeginIndex(){ ?n<F?~
return beginIndex; ot7f?tF2<J
} ~d&&\EZ
:[l}Bb,
/** +m
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* @param beginIndex HCr}|DxyK
* The beginIndex to set. Hva!6vwO%O
*/ =9,mt
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publicvoid setBeginIndex(int beginIndex){ Q=!QCDO(
this.beginIndex = beginIndex; QH><!
sa
} .;31G0<w2
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/** #U0| j?!D
* @return trwo(p
* Returns the currentPage. $Ud9v 4
*/ CXn?~m&K
publicint getCurrentPage(){ ZWGelZP~
return currentPage; ],AtR1k
} bBINjs8C_
/7B3z}rd
/** bh"
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* @param currentPage euY+jc%
* The currentPage to set. 3K(/=
*/ <.g)?nj1
publicvoid setCurrentPage(int currentPage){ "viZ"/~6
this.currentPage = currentPage; 8;~,jZ
s
} W\Il@Je;
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/** :hOB
* @return 1V5N)ty
* Returns the everyPage. v+EJ
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*/ $lB!Q8a$
publicint getEveryPage(){ yo5-x"ze
return everyPage; / !h<+
} K4Ed]hX
<> HI(6\@Z
/** j}lne^ h
* @param everyPage LP7jCt
* The everyPage to set. UptKN|S&V
*/ xz:
publicvoid setEveryPage(int everyPage){ 1_&W1o
this.everyPage = everyPage; LB7$&.m'B
} p8]X Ne
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/** u YFy4E3
* @return uj}%S_9
* Returns the hasNextPage. kFQo[O]
*/ o7tlkSZ
publicboolean getHasNextPage(){ z xgDaT
return hasNextPage; E0i!|H
} O&CY9
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/** fZs}u<3Q)
* @param hasNextPage Ai%Wt-
* The hasNextPage to set. ?/3{gOgI$`
*/ </9c=GoJ
publicvoid setHasNextPage(boolean hasNextPage){ T*k{^=6"!
this.hasNextPage = hasNextPage; %7[d5[U~ZA
} }q_Iep
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/** =J-&usX
* @return M;g"rpM
* Returns the hasPrePage. QeQwmI
*/ abe5 As r
publicboolean getHasPrePage(){ N#OO{`":Z`
return hasPrePage; WYvcN8F
} gT fA]
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/** 4\U"e*
* @param hasPrePage ) WkN34Q
* The hasPrePage to set. Yg!fEopLb
*/ M%13b$i~f
publicvoid setHasPrePage(boolean hasPrePage){ AGlFbc(L
this.hasPrePage = hasPrePage; d^Cv9%X
} mg3YKHNG
tTq2AR|
/** h ^zcM_
* @return Returns the totalPage. [2!?pVI
* R-Tf9?)
*/ ,[| i^
publicint getTotalPage(){ 74Aecb{
return totalPage; :2t?0YR
} *6(/5V
KWVl7Kw#e
/** /GP:W6:6z6
* @param totalPage Zh:@AFz:R
* The totalPage to set. 0;5qo~1
*/ b5
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#
publicvoid setTotalPage(int totalPage){ of_Om$
this.totalPage = totalPage; p?s[I)e
} (Kkqyrb
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} EzU=q
E
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Nk\/lK\
{tXyz[;i1}
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 t%s(xz#1
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个PageUtil,负责对Page对象进行构造: 4n\O6$&.x
java代码: !5zj+N
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/*Created on 2005-4-14*/ U)S!@2(4
package org.flyware.util.page; yD^Q&1
CDFX>>N
import org.apache.commons.logging.Log; dEoW8 M#
import org.apache.commons.logging.LogFactory; ;`Wh^Qgi
OYIH**?
/** 35#"]l"
* @author Joa 4^w`]m
* 8{%[|Ye
*/ 0e~4(2xK
publicclass PageUtil { \BdQ(rm
LyT[
privatestaticfinal Log logger = LogFactory.getLog Z-'xJq
&Y8S! W@4
(PageUtil.class); LeXkl=CC
3B ;aoejHm
/** *46hw(L
* Use the origin page to create a new page 1NU@k6UHl
* @param page ?wj1t!83
* @param totalRecords |("zW7g
* @return Xa=oEG
*/ 8(GJz ~y
publicstatic Page createPage(Page page, int idP2G|Z
5cSqo{|En
totalRecords){ X2C&q$8
return createPage(page.getEveryPage(), =8 Jq'-da
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page.getCurrentPage(), totalRecords); "D/\&1.&
} Ov~>* [
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/** ]n&Eb88
* the basic page utils not including exception ,g bQqoLV
j |:{ B
handler =7%c*O <
* @param everyPage
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* @param currentPage `Ct fe8
* @param totalRecords %b3s|o3An
* @return page &/]g@^h9
*/ ]@mV9:n{
publicstatic Page createPage(int everyPage, int #BwkbOgr
{P
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currentPage, int totalRecords){ 3q$"`w
everyPage = getEveryPage(everyPage); L3^+`e
currentPage = getCurrentPage(currentPage); 5(&'/U^
int beginIndex = getBeginIndex(everyPage, ~&T%u.u7
~BD 80s:f
currentPage); iz\GahK
int totalPage = getTotalPage(everyPage, ycSC'R
~{gV`nm=J
totalRecords); w4\g]\
boolean hasNextPage = hasNextPage(currentPage, T!Eyq,]
`l`)Cs;a
totalPage); L{AfrgN
boolean hasPrePage = hasPrePage(currentPage); H.]rH,8
-}Q^A_xK
returnnew Page(hasPrePage, hasNextPage, u|D|pRM-LT
everyPage, totalPage, QwgP+ M+
currentPage, 4 .d~u@=
DmpG35Jk
beginIndex); 3=xN)j#B
} #u<n .
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privatestaticint getEveryPage(int everyPage){ +{pS2I}d
return everyPage == 0 ? 10 : everyPage; d{G*1l(X
} }2~$"L,_
=^S1+B
MY-
privatestaticint getCurrentPage(int currentPage){ 7c
aV-8:
return currentPage == 0 ? 1 : currentPage; ;dE'# Kb
} AvEd?
S{F'k;x/5
privatestaticint getBeginIndex(int everyPage, int [5sa1$n96G
4-veO3&.h
currentPage){ SdQ"S-H
return(currentPage - 1) * everyPage; JUlCj#%
} 0L|D1_k[
U
*']7-
privatestaticint getTotalPage(int everyPage, int A/w7(
pLea 4
totalRecords){ 86<[!ZM
int totalPage = 0; X4Y!Z/b
;<)<4N"
if(totalRecords % everyPage == 0) kKEs >a
totalPage = totalRecords / everyPage; @eU5b63jM
else TIre,s)_
totalPage = totalRecords / everyPage + 1 ; < k?jt
:FqHMN
return totalPage; z*B-`i.
} TG@ W:>N(
+_ZXzzcO<
privatestaticboolean hasPrePage(int currentPage){ OX[pK_:`l
return currentPage == 1 ? false : true; 1^_V8dm)
} Y+0HC2(o
65||]l
privatestaticboolean hasNextPage(int currentPage, B #zU'G*Y
TZYz`l+v
int totalPage){ 5T- N\)@
return currentPage == totalPage || totalPage == o"-*,:Qe
Ir :y#
0 ? false : true; oZSPdk
} $F/Uk;*d!
.`Rju|l
{Jn*{5tZ>
} 8ZPjzN>c6
.1#G*A|
~|5B
/Dk`vn2 eN
6
r}R%{
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 I`
+%ab
X[r\ Qa
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 9qXKHro
TM2pE/P
做法如下: (Ceq@eAlT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 _m2p>(N|
k;c>=B)e
的信息,和一个结果集List: &h_do8R
java代码: h#Q Sx@U6
MWZH-aA(.
O{w'i|
/*Created on 2005-6-13*/ IP=."w
package com.adt.bo; E\lel4ai
t],5{UF
import java.util.List; gOL-b9W
N~t4qlC/
import org.flyware.util.page.Page; LZF%bJv
#9FY;~
/** LL"c 9jb4z
* @author Joa +xG
*/ xR`M#d5"
publicclass Result { ?&rt)/DV,
4<(U/58a*
private Page page; 3:~ *cU
D,sb{N
private List content; c|KN@)A
ll8Zo+-[
/** ?@YABl
* The default constructor 2=V~n)'a
*/ -}$mv
public Result(){ 6Ud6F t6
super(); 6<qVeO&uZ
} U1 ;<NUg
+fRABY5C
/** !Un&OAy.!
* The constructor using fields 6#za\[
* *iwVB^^$
* @param page n1J;)VyR
* @param content odaCKhdk
*/ '%y5Dh
public Result(Page page, List content){ eb#p-=^KP
this.page = page; |Ta-D++]'
this.content = content; :Cdqj0O3u
} Cyu= c1D ;
'Vz Yf^
/** ` 5lW
* @return Returns the content. f<;w1sM\
*/ :HW\awv
publicList getContent(){ ])tUXU>
return content; iPeW;=-2Wk
} kX)QHNzP
'Tbdo >y
/** 8K@>BFk1.
* @return Returns the page. vzH"O=
*/ Iy8fN"I9D
public Page getPage(){ |zCT~#
return page; #Bo3:B8
} 6i`Y]\X~#
-~=?g9fGm6
/** :pXY/Pa
* @param content U"L7G$
* The content to set. %|AXVv7IN>
*/ tB)nQw7
public void setContent(List content){ +L
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this.content = content; 3]wV 1<K
} d$qi.%<kh
nBkzNb{"AZ
/** rm?C_
* @param page ;6AanwR6
* The page to set. #ni:Bwtl{
*/ oo-O>M#5
publicvoid setPage(Page page){ + J` Qv,0
this.page = page; H9%[!
RF
} 64LAZEQX
} [M/0 Qx[,
,`,1s9\&t
wmB_)`QNP
f~t5[D(\Q,
1G<S'd+N
2. 编写业务逻辑接口,并实现它(UserManager, M'|?*aNK
LTWiCI
UserManagerImpl) [!ilcHE)
java代码: A~M .v0
vTsMq>%,<
B]#^&89wG)
/*Created on 2005-7-15*/ des.TSZ
package com.adt.service; >1 %|T
twP%+/g]<
import net.sf.hibernate.HibernateException; y%!zXK`cl]
FxdWJ|rN9D
import org.flyware.util.page.Page; \&\U&^?
31&;3?3>
import com.adt.bo.Result; @p%WFNR0
iiLDl
/** T6nc/|Ot
* @author Joa \5P 5N]]
*/ q#PMQR"C
publicinterface UserManager { :j&- Lc
\OE,(9T2P.
public Result listUser(Page page)throws SQT]'
D%~"]WnZ\Q
HibernateException; Rrw6\iO
vlC$0P
} * -X`^R
5$ &',v(
g&r3;
lS{ ^*(a
>XPR)&t
java代码: ?h)T\z
66{Dyn7J~
K1CgM1 v
/*Created on 2005-7-15*/ h{ T{3
package com.adt.service.impl; }6"l`$=Ev
&G)/i*
import java.util.List; C;0VR
Hq
aay
import net.sf.hibernate.HibernateException; ~A_1he~
y<kg;-& 8
import org.flyware.util.page.Page; 3w}ul~>j
import org.flyware.util.page.PageUtil; :"'*1S*
3}5Ya\x
import com.adt.bo.Result; WI1DL&*B@<
import com.adt.dao.UserDAO; %$'Z"njO&
import com.adt.exception.ObjectNotFoundException; }poLHS/
import com.adt.service.UserManager; z:oi@q
"#P#;]\ `
/** x}~Z[ bx
* @author Joa sspGB>h8l
*/ R>hL.+l.
publicclass UserManagerImpl implements UserManager { d)kOW!5\
xbzO'C
private UserDAO userDAO; j[4l'8Ek
+zf`_1+)U
/** J\hqK*/8
* @param userDAO The userDAO to set. )Lg~2]'?j
*/ MIY`"h0*
publicvoid setUserDAO(UserDAO userDAO){ gjzU%{T?
this.userDAO = userDAO; w[g`)8Ib
} l
p|`n
DfX~}km
/* (non-Javadoc) ?Xj@Sx
* @see com.adt.service.UserManager#listUser :A+}fBIN
nh? JiH
{
(org.flyware.util.page.Page) xy-Vw"I[bh
*/ "dHo6CT,y_
public Result listUser(Page page)throws ^qLesP#
B\tm
HibernateException, ObjectNotFoundException {
@<koL
int totalRecords = userDAO.getUserCount(); vr4{|5M
if(totalRecords == 0) U~w8yMxX
throw new ObjectNotFoundException )JhB!P(
:xk+`` T
("userNotExist"); z.;!Pj
page = PageUtil.createPage(page, totalRecords); UAGh2?q2
List users = userDAO.getUserByPage(page); gOr%N!5
returnnew Result(page, users); qq"0X! w
} j>G|Xv
8x-(7[#e<g
} 0xH&^Ia1B
<Qt9MO`a
DDj:(I?,w
G4ycP8
erOj(ce
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |>b;M,`OO
y"k%Wa`*
询,接下来编写UserDAO的代码: yIg^iZD
3. UserDAO 和 UserDAOImpl: ji<(}d~L*
java代码: _<'?s>(U'
Ymf@r?F<
%~[@5<p
/*Created on 2005-7-15*/ h)^|VM
package com.adt.dao; T^q^JOC4
S
R s
import java.util.List; vy-q<6T}:p
& jm1
import org.flyware.util.page.Page; @sUec
o.V
JnrJ
import net.sf.hibernate.HibernateException; Qe_C^(P
)Myx(w"S
/** HX ,\a`
* @author Joa z:=E-+
*/ c]"w0a-`^@
publicinterface UserDAO extends BaseDAO { .)<l69ZD Z
\Nk578+AA
publicList getUserByName(String name)throws iUs_)1
Tj}%G
HibernateException; .>S1do+
Awr(}){
publicint getUserCount()throws HibernateException; 'K\H$<CJ
dptfIBYc+
publicList getUserByPage(Page page)throws y;_F[m
ab`9MJc;
HibernateException; RKp9[^/?
39I|.B"
} m'M5O@?
'
H4m"
#CcEI
t{,e{oZx
Zu4au<
java代码: ]x(6^:D5
*=tA },`\7
ZQn>+c2%!
/*Created on 2005-7-15*/ dKhS;!K9p
package com.adt.dao.impl; <$ qT(3w<y
+VL:O]`DJ
import java.util.List; _#
cM vlk
C~pQJ@bF0
import org.flyware.util.page.Page; >v f-,B
wPq9`9 #
import net.sf.hibernate.HibernateException; sp+'c;a
import net.sf.hibernate.Query; "H=N>=g0E
g~U<0+&yw%
import com.adt.dao.UserDAO; cP\ZeG#<
=R ZPDu
/** Bd- &~s^
* @author Joa 3i\Np =
*/ ;-_ZWk]
public class UserDAOImpl extends BaseDAOHibernateImpl uG/'9C6Z
H[}lzL)
implements UserDAO { ?zfm"o
#m;o)KkH$r
/* (non-Javadoc) 4iZg2"[D
* @see com.adt.dao.UserDAO#getUserByName ,v`03?8l(
A8-a}0Gh
(java.lang.String) *rB@[(/
*/ A~X\ dcn
publicList getUserByName(String name)throws Db !8N
/F46Ac}I
HibernateException { ].2t7{64
String querySentence = "FROM user in class k~I]Y,
$zF%F.rln
com.adt.po.User WHERE user.name=:name"; sLFZ61rT
Query query = getSession().createQuery 7SNdC8GZ~
947;6a%$
(querySentence); :X:s'I4J
D
query.setParameter("name", name); [rW];H8:~
return query.list(); KP
6vb@(6
} u /DE
TL)7X.1'L
/* (non-Javadoc) n5;@}Rai
* @see com.adt.dao.UserDAO#getUserCount() 1hSV/%v_
*/ pvb&vtp
publicint getUserCount()throws HibernateException { *e<}hmDr
int count = 0; 'X6Z:dZY
String querySentence = "SELECT count(*) FROM <
Wp)Y
PgA1:i&'
user in class com.adt.po.User"; IP@3R(DS%
Query query = getSession().createQuery KN"u PW
$ M/1pZ
(querySentence); =vvd)og
count = ((Integer)query.iterate().next wm Ie x
:U/]*0b
()).intValue(); <Q"G
aqZ
return count; o!U(=:*b
} [zXC\)&!
!^s -~`'\~
/* (non-Javadoc) fD3'Ye<R
* @see com.adt.dao.UserDAO#getUserByPage sjb.Ezoq3
`'>~(8&zE
(org.flyware.util.page.Page) Lusd kc7
*/ '[HQ}Wvn
publicList getUserByPage(Page page)throws !uO@4]:Y
WRwx[[e6z
HibernateException { !3\$XK]5ZT
String querySentence = "FROM user in class 9Kgyt
pKGhNIj$
com.adt.po.User"; DVMdRfA
Query query = getSession().createQuery 1P'A*`!K
#sBL E
(querySentence); .tppCy
query.setFirstResult(page.getBeginIndex()) K=E+QvSG
.setMaxResults(page.getEveryPage()); m#i4_F=^b
return query.list(); {MyI3mvA
} IG{Me
R9Wr?
} D_[NzCv<-
7Z~JuTIZ
w!v^6[!
=wW M\f`=
?1c7wEk
至此,一个完整的分页程序完成。前台的只需要调用 d*VvQU8C
u[PG/ploc
userManager.listUser(page)即可得到一个Page对象和结果集对象 RAk"C!&^m
"Da-e\yA
的综合体,而传入的参数page对象则可以由前台传入,如果用 WTM
6({)O1Z
webwork,甚至可以直接在配置文件中指定。 l6 }+,v@#
sD2,!/'
下面给出一个webwork调用示例: v\MQ?VC
java代码: w{|`F>f9
Rm}5AJ
C.":2F;-e
/*Created on 2005-6-17*/ >~]|o
package com.adt.action.user; kB=B?V~#
@$ Nti>
import java.util.List; jkta]#O
6<>1,wbq
import org.apache.commons.logging.Log; &|}QdbW
import org.apache.commons.logging.LogFactory; - 0q263z
import org.flyware.util.page.Page; 3e47UquZ
9I2&Vx=DSt
import com.adt.bo.Result; K3`!0(
import com.adt.service.UserService; l4.ql1BX@y
import com.opensymphony.xwork.Action; ^Y;,cLXJ
upk+L^
/** g6aqsa
* @author Joa @ S[As~9X
*/ *?~"Jw
publicclass ListUser implementsAction{ i+in?!@G:
a^|9rho<
privatestaticfinal Log logger = LogFactory.getLog Ba5*]VGG
S)wP];]`K
(ListUser.class); +boL?Ix+
P0(LdZH6u
private UserService userService; ='w 2"4
OFmHj]I7=
private Page page; CLe{9-o
4 qY
privateList users; "S6";G^I
d4ld-y
/* o _l_Yi
* (non-Javadoc) 8 >LDo"<
* B8"c+<b
* @see com.opensymphony.xwork.Action#execute() y!}XlllV
*/ i2(v7Gef
publicString execute()throwsException{ (ER9.k2
Result result = userService.listUser(page); `''y,{Fs
page = result.getPage(); _?cum~A@
users = result.getContent(); ;|oft-y
return SUCCESS; )u28:+8
} _'1 ]CoR
V!Sm,S(
/** _deEs5i
* @return Returns the page. 6|
o S 5
*/ pjTJZhT2 I
public Page getPage(){ Sy1O;RTn`
return page; 7B\NP`l
} dI%ho<zm]
iymN|KdpaZ
/**
Y/I)ECm
* @return Returns the users. <]KQ$8dtD
*/ 4vN:Kj
publicList getUsers(){ _izjvg
return users; @R%qP>_
} dR< d7
-P|claO0
/** Sew*0S(
* @param page ]1>R8
* The page to set. uKXD(lzX
*/ ::#[lw
publicvoid setPage(Page page){ .;Gx.}ITG6
this.page = page; Z'2AsT
} czu9a"M>X
JrLh=0i9
/** Hd\oV^>
* @param users hLuv
* The users to set. #-f9>S9_
*/ ty#6%
publicvoid setUsers(List users){ }v|_]
this.users = users; F:P2:s<d-
} <bo)p6S&
Wu|MNB?M
/** cAwqIihZ
* @param userService MI(#~\Y~P
* The userService to set. {5X,xdzR
*/ l=l$9H,
publicvoid setUserService(UserService userService){ /Mw;oP{&b
this.userService = userService; &k_*Y-l7]
} uQx/o^
} ]>Z9K@
%~M* <pN
sU*?H`U3d
\n,L600`q
g~.#.S ds
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, f sh9-iY8e
>2pxl(i
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 nr
-< mQ
R_+:nCB@,
么只需要: CR9wp]-Vd
java代码: Jh&DL8`
: Bo
#;^U W
<?xml version="1.0"?> h6O'"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork NNqvjM-
ElB[k<
1.0//EN" "http://www.opensymphony.com/xwork/xwork- K/N{F\
~BuBma_
1.0.dtd"> fi*b]a\'
,C><n
kx
<xwork> u*=^>LD
&uO-h
<package name="user" extends="webwork- $<2d|;7r
B&rN