Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 gMkSl8[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 l+hOD{F4pS
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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 `ah|BV
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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 O|^J;fS:
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分页支持类: J]{<Z?%
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java代码: r)K5<[\r
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package com.javaeye.common.util; Y Q.Xl_
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import java.util.List; J:&.[
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publicclass PaginationSupport { '`2MxRP
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publicfinalstaticint PAGESIZE = 30; jX(${j<
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privateint pageSize = PAGESIZE; _od /)#
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privateList items; C<I?4WM
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privateint totalCount; 3!fR'L/i
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privateint[] indexes = newint[0]; =N{?ll6x7g
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privateint startIndex = 0; @SiV3k
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public PaginationSupport(List items, int .!Z5A9^
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totalCount){ C,W_0=!e
setPageSize(PAGESIZE); CLVT5pj='
setTotalCount(totalCount); 8~R.iqLoX
setItems(items); $hcv}<$/
setStartIndex(0); 'iZwM>l\
} g |?}a]G
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public PaginationSupport(List items, int #<9'{i3
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totalCount, int startIndex){ qp6'n&^&
setPageSize(PAGESIZE); &ZC{ _t
setTotalCount(totalCount); ro<w8V9.a
setItems(items); Qu=b-9
setStartIndex(startIndex); <5pNFj}0;X
} !J#P'x0
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public PaginationSupport(List items, int \M@IKE
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totalCount, int pageSize, int startIndex){ hf9i%,J
setPageSize(pageSize); t!/~_}eD J
setTotalCount(totalCount); ]f&]E
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setItems(items); "'Fvt-<^S7
setStartIndex(startIndex); 6 *S/frE
} 9H4"=!AAgD
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publicList getItems(){ `^8mGR>OpI
return items; Z'k?lkB2i
} leNX5 sX
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publicvoid setItems(List items){ )hO%W|
this.items = items; P8dMfD*"E
} MDIPoS3BRa
}6%\/d1~ 6
publicint getPageSize(){ iH-,l
return pageSize; 2Q@na@s
} wAi7jCY%OY
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publicvoid setPageSize(int pageSize){ {4vWSb
this.pageSize = pageSize; P(8Yz W
} aDX&j2/
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publicint getTotalCount(){ 8NNh8k#6
return totalCount; ,R-k]^O
} BRu}"29
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publicvoid setTotalCount(int totalCount){ {*hFG:u
if(totalCount > 0){ ;5\'PrE
this.totalCount = totalCount; Kzq^f=p
int count = totalCount / PuZzl%i
P3
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pageSize; 4j'rbbs/
if(totalCount % pageSize > 0) Ei]SksV>*
count++; ;DZj.|Sj+
indexes = newint[count]; E,?IIRg&
for(int i = 0; i < count; i++){ FYC]^D
indexes = pageSize * 'Tqusr>lPY
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i; dly -mPmP
} RJDk7{(
}else{ kl1Q:
this.totalCount = 0; U5cbO{\3I
} uInI{>
} xp3^,x;\X
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publicint[] getIndexes(){ UL~~J[1r
return indexes; FR'Nzi$
} ~LFM,@
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publicvoid setIndexes(int[] indexes){ oGeV!hD
this.indexes = indexes; 8>vNa
} !]mo.zDSW5
}4c$_
publicint getStartIndex(){ 16z
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return startIndex; I-J%yutB
} 6y`FW[
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publicvoid setStartIndex(int startIndex){ %Y|AXxR
if(totalCount <= 0) i6;rh-M?.
this.startIndex = 0; 4>Q] \\Lc
elseif(startIndex >= totalCount) q~AvxO
this.startIndex = indexes I%j]p Y4
0f+]I=1\
[indexes.length - 1]; ,gkWksl9
elseif(startIndex < 0) chuJj
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this.startIndex = 0; 5(Q-||J
else{ >E,/|K*
this.startIndex = indexes %md9ou`
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[startIndex / pageSize]; dj 6Lf
} q7rX4-G$
} @ <'a0)n>
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publicint getNextIndex(){ zFwO(
int nextIndex = getStartIndex() + TQ {8 ee{
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pageSize; D9r;Ys%
if(nextIndex >= totalCount) `E>o:tff
return getStartIndex(); FQMA0"(G$
else Hu!<GB~
return nextIndex; >4T7DMy
} I=K<%.
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publicint getPreviousIndex(){ ]RW*3X
int previousIndex = getStartIndex() - m{6*ae
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pageSize; 8O*O5
if(previousIndex < 0) 3\P/4GK)
return0; LkXF~
else hN1{?PQ
return previousIndex; r*ry8QA
} ^F/H?V/PX
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} V ;M'd@
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抽象业务类 fAeq(tI=
java代码: )XD$YI
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/** ]3yaIlpD1
* Created on 2005-7-12 #c2JWDH1F
*/ ?s{Pp
package com.javaeye.common.business; Z <tJ+
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import java.io.Serializable; &1Idv}@!
import java.util.List; :mz6*0qW
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import org.hibernate.Criteria; '${xZrzmt
import org.hibernate.HibernateException; UPJ3YpK
import org.hibernate.Session;
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import org.hibernate.criterion.DetachedCriteria; #+Cu&l
import org.hibernate.criterion.Projections; FOd)zU*L2
import cYp]zn+6
+&hd3
org.springframework.orm.hibernate3.HibernateCallback; p_2-(n@
import h48
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8!{F6DG
org.springframework.orm.hibernate3.support.HibernateDaoS }*I:0"WH
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upport; ht%:e?@i
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import com.javaeye.common.util.PaginationSupport; E)w^odwMU
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public abstract class AbstractManager extends UFy"hJchO
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HibernateDaoSupport { 4=E9$.3a
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privateboolean cacheQueries = false; Una7O]
~ g \GC
privateString queryCacheRegion; LD~/*
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publicvoid setCacheQueries(boolean xG^6'<
D> |R.{
cacheQueries){ b+.P4+
this.cacheQueries = cacheQueries; ir%?J&C+t
} J`*!U4
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publicvoid setQueryCacheRegion(String "[ 091 <
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queryCacheRegion){ 6ZCSCBW
this.queryCacheRegion = CnT]uU
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queryCacheRegion; k<098F
} H53dy*wb$
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publicvoid save(finalObject entity){ Bg?f}nu7
getHibernateTemplate().save(entity); Ungex@s_
} H]7MN Y
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publicvoid persist(finalObject entity){ 6^M!p4$hF
getHibernateTemplate().save(entity); mlsM;Ad2
} =@F1J7
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publicvoid update(finalObject entity){ nwOT%@nw
getHibernateTemplate().update(entity); C 'YL9r-G
} =BN_Kvza^6
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publicvoid delete(finalObject entity){ h/7m.p]
getHibernateTemplate().delete(entity); 95
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} \G+ hi9T(
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publicObject load(finalClass entity, n*UD0U}`
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finalSerializable id){ $IZ02ZM$
return getHibernateTemplate().load
){u/v[O9"
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(entity, id); X,)`<
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} eI%{/>
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publicObject get(finalClass entity, ;7jszs.6%
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finalSerializable id){ P4&3jQ[o
return getHibernateTemplate().get .c+NsI9}
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(entity, id); eXB'>#&s
} - '<K_e;
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publicList findAll(finalClass entity){ 8`QbUQ6
return getHibernateTemplate().find("from }@Ap_xW
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" + entity.getName()); _,,w>q6K
} d:j65yu
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publicList findByNamedQuery(finalString v:$Ka@v6
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namedQuery){ 0j}!4D+
return getHibernateTemplate 8>\tD
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().findByNamedQuery(namedQuery); })?t:zX#*
} I34|<3t$
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publicList findByNamedQuery(finalString query, | e?:Uq
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finalObject parameter){ "!g}Q*
return getHibernateTemplate iE6?Px9]
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().findByNamedQuery(query, parameter); u~]O #v
} y-.<iq
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publicList findByNamedQuery(finalString query, ij=_h_nA
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finalObject[] parameters){ H Q_IQ+
return getHibernateTemplate Rj'Tu0l
qh]D=i
().findByNamedQuery(query, parameters); rGn6S&-
} H(QbH)S$6
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publicList find(finalString query){ Y\
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return getHibernateTemplate().find : Yb_
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(query); ,6EFJVu
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} u]766<Z
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publicList find(finalString query, finalObject .FdzEauVc
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parameter){ [.Y]f.D
return getHibernateTemplate().find .gJv})Vi
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(query, parameter); N|3a(mtiZ'
} 8+n*S$
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public PaginationSupport findPageByCriteria Jwtt&" c0.
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(final DetachedCriteria detachedCriteria){ bCg)PJuB
return findPageByCriteria r @URs;O=
q |Orv=v
(detachedCriteria, PaginationSupport.PAGESIZE, 0); peZ'sZ 6
} ?58*#'r
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public PaginationSupport findPageByCriteria TNF+yj-|X:
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(final DetachedCriteria detachedCriteria, finalint p_EWpSOt7
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startIndex){ b\Mb6s
return findPageByCriteria k0IztFyj:R
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(detachedCriteria, PaginationSupport.PAGESIZE, Y?4N%c_;
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startIndex); Kwo0%2Onkd
} 'EO"0,
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public PaginationSupport findPageByCriteria tKCX0UZ'
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(final DetachedCriteria detachedCriteria, finalint {S"! c.
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pageSize, *d}{7UMy#
finalint startIndex){ X8 x:/]/0
return(PaginationSupport) ]DK.4\^
L[. )!c8k
getHibernateTemplate().execute(new HibernateCallback(){ MmW]U24s
publicObject doInHibernate &&TAX
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(Session session)throws HibernateException { 4=ZN4=(_[
Criteria criteria = ,H5o/qNU`{
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detachedCriteria.getExecutableCriteria(session); I7{
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int totalCount = $j'8Z^
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((Integer) criteria.setProjection(Projections.rowCount P+(Ys[J3
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()).uniqueResult()).intValue(); F5YHc$3^
criteria.setProjection "/zDcZbL;
QUi=ZD1
(null); z{G@t0q
List items = h 7*#;j
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criteria.setFirstResult(startIndex).setMaxResults @^K_>s9B
=d1R9O
(pageSize).list(); Y%YPR=j~ &
PaginationSupport ps = 'H)l~L
x#TWZ;
new PaginationSupport(items, totalCount, pageSize, H^0`YQJ3
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startIndex); "jAEZ
return ps; mx")cGGQ
} KI8Q
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}, true); m|cT)-
} .="[In'
}Oh@`xTxt
public List findAllByCriteria(final #wL8=QTcNC
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DetachedCriteria detachedCriteria){ m/>z}d05h
return(List) getHibernateTemplate y3)R:h4AH
F ][QH\N
().execute(new HibernateCallback(){ .LEn~ 8
publicObject doInHibernate PU{7s
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(Session session)throws HibernateException { #e(P~'A0
Criteria criteria = X~5kgq0"
h?2 :'Vu]
detachedCriteria.getExecutableCriteria(session); T0Zv.
return criteria.list(); A]CO
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} ]Qb85;0)
}, true); -~
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} qra5&Fvb
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public int getCountByCriteria(final kpt0spp
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DetachedCriteria detachedCriteria){ )a'c_ 2[
Integer count = (Integer) UkV{4*E
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getHibernateTemplate().execute(new HibernateCallback(){ ~LuR)T=%es
publicObject doInHibernate pCm |t!,
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(Session session)throws HibernateException { =/]d\JSp
Criteria criteria = 3~Vo]wv
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detachedCriteria.getExecutableCriteria(session); *1fZcw'C.
return qX?k]m
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criteria.setProjection(Projections.rowCount Z )f\^
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()).uniqueResult(); !O~5<tA[#1
} V=|X=:fuih
}, true); 4)=\5wJDg1
return count.intValue(); :6Oh ?y@
} =2yg:D
} =7WE
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用户在web层构造查询条件detachedCriteria,和可选的 ,awp)@VG7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0aS&!"o!
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PaginationSupport的实例ps。 8+7=yN(
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ps.getItems()得到已分页好的结果集 .g6DKjy>
ps.getIndexes()得到分页索引的数组 k TLA["<m
ps.getTotalCount()得到总结果数 0G.y_<=
ps.getStartIndex()当前分页索引 P_f>a?OL:
ps.getNextIndex()下一页索引 @94_'i7\
ps.getPreviousIndex()上一页索引 ]%K 8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 +|w-1&-
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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 Gv};mkX[N
-
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一下代码重构了。 p<@0b
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我把原本我的做法也提供出来供大家讨论吧: ktr l |
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首先,为了实现分页查询,我封装了一个Page类: W_zAAIY_Y
java代码: tilL7
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/*Created on 2005-4-14*/ T&2aNkuG
package org.flyware.util.page; -k19BDJ,W
3??*G8Yp
/** I\0mmdi73
* @author Joa 2HNH@K
* ]g/%w3G
*/ 7b2N'^z}
publicclass Page { ]byj[Gd
^%v<I"<Uq5
/** imply if the page has previous page */ aeESS;JxJj
privateboolean hasPrePage; 3f{%IU(z
ZcXqH7`r
/** imply if the page has next page */ p[QF3)9F
privateboolean hasNextPage; od- 0wJN-m
c0Tda
/** the number of every page */ eTc0u;{V
privateint everyPage; ] Qp0|45=
SR#%gR_SC
/** the total page number */ %NbhR(
privateint totalPage; S-8O9
.&ynS
/** the number of current page */ >mT< AQ
privateint currentPage; `'u|4pRFs
2w=0&wG4K
/** the begin index of the records by the current -IR9^)
<dTo-P
query */ ms=Ilz
privateint beginIndex; Riq5Au?*)
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/** The default constructor */ '|e5 cW6z
public Page(){ V(3udB@K
46'EZ@#s
} ~9qDmt,i
DTdL|x.{
/** construct the page by everyPage K<b -|t9f
* @param everyPage 5Mb1==/R
* */ x3L3K/qMg
public Page(int everyPage){ L4aT=of-
this.everyPage = everyPage; #Dx$KPD
} #(@dN+
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/** The whole constructor */ r+HJ_R,5A
public Page(boolean hasPrePage, boolean hasNextPage, J#CF S G
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int everyPage, int totalPage, xH\'gli/
int currentPage, int beginIndex){ vKDPg p<j
this.hasPrePage = hasPrePage; io:?JnQSA
this.hasNextPage = hasNextPage; tkWWR%c"
this.everyPage = everyPage; 9VIsLk54^
this.totalPage = totalPage; K:P gkc
this.currentPage = currentPage; *#EyfMz-B
this.beginIndex = beginIndex; 4;|&}Ij
} _y`'T;~OY
XH)MBr@Fz
/** c*!bT$]~\
* @return W"|89\p}
* Returns the beginIndex. $,icKa
*/ b n^^|i
publicint getBeginIndex(){ Cs%'Af
return beginIndex; }?>30+42:
} hvGb9
=Ze~6vS,
/** T:wd3^.CG
* @param beginIndex bM8b3,}?n
* The beginIndex to set. TA}gCXE
e
*/ )T?w,"kI
publicvoid setBeginIndex(int beginIndex){ Czb@:l%sc
this.beginIndex = beginIndex; blaxUP:
} 05nG|
wamqeb{u
/** 2c!?!:s
* @return 50rq}-
* Returns the currentPage. (q*T.
*/ qVJV 9n
publicint getCurrentPage(){ ^']xkS
return currentPage; 6}Y^X
} ykl./uY'
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/** )1J&tV*U
* @param currentPage Fg5c;sls
* The currentPage to set. Vjj30f
*/ O|%><I?I
publicvoid setCurrentPage(int currentPage){ l$d 4g?Z
this.currentPage = currentPage; &^qD<eZ!Eq
} ]t7<$L
$CHri|
/** Uh?SDay
* @return 33[2$FBf
* Returns the everyPage. ;% !'K~
*/ E+>Qpy
publicint getEveryPage(){ yZ 6560(q
return everyPage; Y'bDEdeT
} t1g)Y|@d
@?G.6r~
/** R S;r
* @param everyPage %dO'kU /-
* The everyPage to set. WK/Byd.Z
*/ vlm&)DIt
publicvoid setEveryPage(int everyPage){ k=w%oqpN
this.everyPage = everyPage; Q>JJI:uC4
} : B$
d
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/** 1/6 G&RB
* @return (tx6U.Oy
* Returns the hasNextPage. N!/^s":
*/ rMfp%DMA
publicboolean getHasNextPage(){ 7DKbuUK
return hasNextPage; Skp&W*Ai
} ui YZk3
<.s[x~b\`
/** gG~UsA
* @param hasNextPage ~F+{P4%`<
* The hasNextPage to set. cZZ-K?_
*/ :=T+sT~
publicvoid setHasNextPage(boolean hasNextPage){ [[Qu|?KEa
this.hasNextPage = hasNextPage; wC`])z}bT
} ^yu0Veypy
jzdK''CHi
/** mcpM<vY/H
* @return oh :g
* Returns the hasPrePage. t]2~aK<]
*/ j1Q G-Rs&
publicboolean getHasPrePage(){ bh3}[O,L
A
return hasPrePage; e%U0^! 8
} ;l7wme8Qk
NK~j>>^;v
/** D7olu29
* @param hasPrePage f,k'gM{K
* The hasPrePage to set. =UM30
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*/ op/HZa
publicvoid setHasPrePage(boolean hasPrePage){ +(`
this.hasPrePage = hasPrePage; 1<\@i{;xsU
} 7Xw;TA
B'lWs;
/** 506B=
* @return Returns the totalPage. k*w]a
* ,<d[5;7x
*/ jY('?3
publicint getTotalPage(){ 1*Yf[;L
return totalPage; 6
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} u-qg9qXJb
*rXESw]BR
/** ZXY5Xvt:v
* @param totalPage C;1A$]bk
* The totalPage to set. z+@aQ@75
*/ |Z0?
publicvoid setTotalPage(int totalPage){ SWNi@
this.totalPage = totalPage; _rR+u56y-
} X2}\i5{
dpDVEEs84
} o
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[V|,O'X ~
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k?;A#L~
r1\c{5Wt
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 xdd7OSc0{
u}\F9~W-{
个PageUtil,负责对Page对象进行构造: d(3F:dbk
java代码: `TYQ^Zm
wc*5s7_
rjo/-910
/*Created on 2005-4-14*/ @{iws@.
package org.flyware.util.page; zH0%;
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ug'I:#@2
import org.apache.commons.logging.Log; <Bn^+u \
import org.apache.commons.logging.LogFactory; z\Rs?v"
x1:+M]Da
/** J;W(}"cFq
* @author Joa gbsRf&4h
* #=V%S
2~
*/ s:'M[xI
publicclass PageUtil { W=c7>s0>
4v_?i@,L
privatestaticfinal Log logger = LogFactory.getLog /;-KWu+5=
Y9Q-<~\z
(PageUtil.class); nfJ|&'T
ZM K"3c9
/** ([R}s/)$
* Use the origin page to create a new page (o~f6pNB,
* @param page O$k;p<?M
* @param totalRecords ,d(F|5M:
* @return (~:k70V5
*/ rlT[tOVAY
publicstatic Page createPage(Page page, int vA2@Db}
`zGK$,[%
totalRecords){ F1JSf&8
return createPage(page.getEveryPage(), (#Z2
BIEc4k5(
page.getCurrentPage(), totalRecords); 3UU]w`At
} I+Qv $#S/
IMIZ#/
/** t
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* the basic page utils not including exception (f#QETiV
"D}PbT[V
handler fu?5gzT+b
* @param everyPage /e1m1 B
* @param currentPage C7[ge&
* @param totalRecords 4!p~Mr[E
* @return page *vc=>AEc
*/ F`SOF O
publicstatic Page createPage(int everyPage, int W{O:j
jIv%?8+%
currentPage, int totalRecords){ 3v)v92;
everyPage = getEveryPage(everyPage); .281;] =
currentPage = getCurrentPage(currentPage); >8_#L2@
int beginIndex = getBeginIndex(everyPage, py`RH)
-CfGWO#Gbx
currentPage); s\i=-`
int totalPage = getTotalPage(everyPage, eZ5UR014
aehGT|
totalRecords); A"x1MjuqLM
boolean hasNextPage = hasNextPage(currentPage, DE|r~TQ
v+U(
#"
totalPage); oEbgyT gB
boolean hasPrePage = hasPrePage(currentPage); .yE!,^j.gB
j2# nCU54Z
returnnew Page(hasPrePage, hasNextPage, Qna
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everyPage, totalPage, /%C6e
)7BL
currentPage, ;v'7l>w3\w
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hC
beginIndex); :-ZE~bHJ
} ztf
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[RCUP.
privatestaticint getEveryPage(int everyPage){ ;"SnCBt:>
return everyPage == 0 ? 10 : everyPage; OLUQjvnU
} ?z% @;&
/AV
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privatestaticint getCurrentPage(int currentPage){ x7K
return currentPage == 0 ? 1 : currentPage; s:lar4>kM
} F+,X%$A#?
O&l(`*P
privatestaticint getBeginIndex(int everyPage, int :' ?%%P
Y,RED5]t
currentPage){ O=LS~&=,
return(currentPage - 1) * everyPage; hDJq:g
wD
} q4{Pm $OW
G7 >
privatestaticint getTotalPage(int everyPage, int #&0)kr66
'$pT:4EuGq
totalRecords){ UMwB. *
int totalPage = 0; 7)$U>|=
0cZyO$.
if(totalRecords % everyPage == 0) ;l>
xXSB7$
totalPage = totalRecords / everyPage; }uo5rB5D
else D5fJuT-bp
totalPage = totalRecords / everyPage + 1 ; *@o@>
26JP<&%L
return totalPage; *k==2figz
} z_R^n#A~r
<HM\ZDo@P
privatestaticboolean hasPrePage(int currentPage){ &?>h#H222
return currentPage == 1 ? false : true; {PgB~|W
} pw{3I 2Ix
eO;i1 >
privatestaticboolean hasNextPage(int currentPage, BM=`zGh"
8(3'YNC
int totalPage){ CN8GeZ-G
return currentPage == totalPage || totalPage == qJ|ByZ.N+
5x?eun
0 ? false : true; =Xze ).g
} mj5$ 2J
uMa: GDh7
`M/=_O3
} 6}
"?eW
#%z--xuJL
!O
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?xh_qy;
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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。 n4\6\0jq6
4NN-'Z>a
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 j[NA3Vj1P
2uFaAAT
做法如下: v'i"Q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Hn)K;?H4
d,[.=Jqv[
的信息,和一个结果集List: sj a;NL
java代码: ,Hh7'`
nL!h hseH
nR4L4tdS
/*Created on 2005-6-13*/ v:1l2Y)g
package com.adt.bo; cw.Uy(ks|$
A[J9v{bD
import java.util.List; LinARMPv
2+"=i/8
import org.flyware.util.page.Page; :p@H
b7R#tT
/** |57KTiiNLI
* @author Joa r5Ej
*/ WS9n.opl}
publicclass Result { w8:F^{
K+2bNKZ0
private Page page; o_/C9[:
Y<TlvB)w
private List content; heoOOP(#
3~6F`G
/** VOwt2&mZ
* The default constructor RtH[OZu(8
*/ dvxD{UH
public Result(){ AbUU#C7
super(); I=D{(%+^d
} 1~8F&
^.Q{Aqu#.H
/** T[xGF/
* The constructor using fields 8B;`9?CI
* Uy^Hh4|
* @param page
/ :"%m:-P
* @param content nQK@Uy5Yr
*/ ?I}jsm1)
public Result(Page page, List content){ Iu|G*~\
this.page = page; gJi11^PK
this.content = content; -`wGF#}y(=
} CvmZW$5Yo
|[D~7|?
/** w3Aq[1U0
* @return Returns the content. 9bgKu6-X
*/ OQ#gQ6;?0
publicList getContent(){ As@~%0 S
return content; 9;dP7o
} o;FjpZ
#[sC H
/** :d/Z&LXD
* @return Returns the page. 8>j+xbw
*/ <9-tA\`8N
public Page getPage(){ SAs'u"EB
return page; GK/a^[f+'l
} /7@@CG6b
>IfJ.g"
/** q "bpI8j
* @param content ",E6)r
* The content to set. :*tv`:;p
*/ =N<Hc:<t4
public void setContent(List content){ 5yp~PhHf
this.content = content; +<:p`%
} |F<U;xV$p
Ec_
G9&
/** *bn9j>|iv
* @param page <S
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* The page to set. @`}'P115@
*/ QC4_\V>[
publicvoid setPage(Page page){ DetBZ.
this.page = page; #`z!f0
P
} zQ]IlMt
} (n"M)
BOL_kp"
8i-?\VZD
XF\`stEnb
'P@a_*I
2. 编写业务逻辑接口,并实现它(UserManager, =6
Ea\a:
UserManagerImpl) VmBLNM?
java代码: V$q%=Sip
ct~lt'L\
xO1d^{~^^
/*Created on 2005-7-15*/ e-qr d
package com.adt.service; C+5^[V
t T-]Vj.
import net.sf.hibernate.HibernateException; MLBZmM '
U45/%?kE)
import org.flyware.util.page.Page; 7MGc+M(p
ip>dHj
z
import com.adt.bo.Result; _tjFb_}Q
P]y2W#Rs
/** qh.c#t
* @author Joa F,:F9r?l,H
*/ e1<28g
publicinterface UserManager { &`>*3m(
c
|C12b[
public Result listUser(Page page)throws 'c &Bmd40
pQVi&( M
HibernateException; J8b]*2D
ni%^w(J3Q
} ]|[xY8 5}
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?erDP8
"X]ufZ7
FswFY7
8
java代码: "9WP^[
uxh4nyE
ww\/$ |
/*Created on 2005-7-15*/ #=O0-si]P
package com.adt.service.impl; Ix *KL=MG
]iz5VI@
import java.util.List; (|6qN
j zPC9
import net.sf.hibernate.HibernateException; ZVGw@3
H/, tE0ZV
import org.flyware.util.page.Page; fmSw%r|pT
import org.flyware.util.page.PageUtil; ?QuFRl,ZJ
1:>RQPXcWv
import com.adt.bo.Result; *Lh0E/5
import com.adt.dao.UserDAO; [j!0R'T
import com.adt.exception.ObjectNotFoundException; /FYa{.Vlr
import com.adt.service.UserManager; +Nza@B d
hD$U8~zK
/** T8Khm O
* @author Joa hh8UKEM-
*/ p}Gk|Kjlq,
publicclass UserManagerImpl implements UserManager { 71)#'ey
9J%>2AA
private UserDAO userDAO; be764do
!^m5by
/** DI&xTe9k
* @param userDAO The userDAO to set. C#r`oZS1
*/ C$(t`G
publicvoid setUserDAO(UserDAO userDAO){ M,#t7~t
this.userDAO = userDAO; FF_$)%YUp
} NFa
;
i#-Jl7V[a
/* (non-Javadoc) 4u(}eE
f7
* @see com.adt.service.UserManager#listUser %(kq Hxc
n>eIQaV
(org.flyware.util.page.Page) wR4P0[
*/ ?"C]h s
public Result listUser(Page page)throws oVhw2pKpM
Zq`bd55~
HibernateException, ObjectNotFoundException { vc!S{4bN
int totalRecords = userDAO.getUserCount(); +(/Z=4;,[
if(totalRecords == 0) IB?A]oN1{
throw new ObjectNotFoundException (la
ke4q$pD
("userNotExist"); $}F]pa[
page = PageUtil.createPage(page, totalRecords); [n}c}%
List users = userDAO.getUserByPage(page); KC]Jbm{y
returnnew Result(page, users); EjF}yuq[
} *K98z ?
KXM-GIRUG
} ,AD| u_pP
fwnpmuJ
UMX+h])#N
q#778
tFSdi.|G=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K;97/"
,,Db:4qfjD
询,接下来编写UserDAO的代码: .kYzB.3@]
3. UserDAO 和 UserDAOImpl: q+:(@w6
java代码: FlgB-qR]<n
FvNO*'xP
'LOqGpmVc
/*Created on 2005-7-15*/ C0fA3y72
package com.adt.dao; ljis3{kn""
C[KU~@
import java.util.List; (gf\VYM-7
sogbD9Jc
import org.flyware.util.page.Page; #wd \&
B~aOs>1
S]
import net.sf.hibernate.HibernateException; x2B"%3th0
]q3Kd{B
/** ?rOb?cu-
* @author Joa YBCjcD[G
*/ e-')SB
publicinterface UserDAO extends BaseDAO { nSow$6T_
a"DV`jn
publicList getUserByName(String name)throws ICTtubjV"
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HibernateException; vX/A9Qi,U.
wW<"l"x,
publicint getUserCount()throws HibernateException; &`Di cfD
7
b.-&,
publicList getUserByPage(Page page)throws n>0dz#
y;Zfz~z
HibernateException; +{%4&T<nHw
7qUtsDK
} {l11WiqQH
/T(\}Z
1b7xw#gLx
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&+j^{a
java代码: } E#+7a
{^kG<v.vV
._&lG3'
/*Created on 2005-7-15*/ HV9SdJOf
package com.adt.dao.impl; ,?`1ve_K<
pu:D/2R2;k
import java.util.List; :|M/+XPu
\zI&n &T
import org.flyware.util.page.Page; QP[a^5;Tt
pG( knu
import net.sf.hibernate.HibernateException; 9i<-\w^$
import net.sf.hibernate.Query; z^/ GTY
tvOAN|+F
import com.adt.dao.UserDAO; w~U`+2a3
Inc:t_
/** ,/:a77
* @author Joa k4$q|x7+%
*/ bVeTseAG
public class UserDAOImpl extends BaseDAOHibernateImpl MH.,s@
:2pBv#\"qk
implements UserDAO { ww($0A`ek
Uo}&-$ B
/* (non-Javadoc) 7Hl_[n|
* @see com.adt.dao.UserDAO#getUserByName -p.*<y
b H?qijrC
(java.lang.String) >NRz*h #
*/ klJ[ {p
publicList getUserByName(String name)throws b'1d<sD
z>33O5U
HibernateException { "-n%874IT
String querySentence = "FROM user in class EO&ACG
H~|%vjH
com.adt.po.User WHERE user.name=:name"; |NU0tct^
Query query = getSession().createQuery eAsX?iaH
)c*k_/4
(querySentence); !e'0jf-~
query.setParameter("name", name); v$m[#&O^V?
return query.list(); *sB-scD
} 7+a%ehwU
mp,e9Nd;
/* (non-Javadoc) S[~O')
* @see com.adt.dao.UserDAO#getUserCount() =b<<5N s
*/ "'!%};
publicint getUserCount()throws HibernateException { qX+gG",8
int count = 0; ;:4P'FWm^
String querySentence = "SELECT count(*) FROM v"r9|m~ '
T]6c9_
user in class com.adt.po.User"; l-S'ATZ0p
Query query = getSession().createQuery nh eU~jb
,=Nw(GI
(querySentence);
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count = ((Integer)query.iterate().next gXu^"
^+as\
()).intValue(); 6%kJDY.
return count; '^Utbp2<
} tP`G]BCbt
}@14E-N=
/* (non-Javadoc) Y#lk!#\Y
* @see com.adt.dao.UserDAO#getUserByPage adI!W-/R:
)@,90Vhh
(org.flyware.util.page.Page) t@(9ga(
*/ 9Yl8ndP^E
publicList getUserByPage(Page page)throws 30?LsYXL62
'cZMRRc<
HibernateException { )[^y
t0%
String querySentence = "FROM user in class }r}RRd
sLG>>d3R1
com.adt.po.User"; `~_H=l9{
Query query = getSession().createQuery 3e%l8@R@
Or+*q91j
(querySentence); (/U)>%n
query.setFirstResult(page.getBeginIndex()) ahNX/3;y
.setMaxResults(page.getEveryPage()); LZr0]g{Pu/
return query.list(); %o@['9U[j
} dK}WM46$
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} Q1`<fD
dP$8JI{
zb;(?!Bd#
y9C;T(oi;
*N-;V|{
至此,一个完整的分页程序完成。前台的只需要调用 ~=:2~$gsn
U{uPt*GUd/
userManager.listUser(page)即可得到一个Page对象和结果集对象 !/Iq{2LX
DS:>/m>)
的综合体,而传入的参数page对象则可以由前台传入,如果用 U*3AM_w
ItI0x
webwork,甚至可以直接在配置文件中指定。 AH2_#\
x&C%4Y_]
下面给出一个webwork调用示例: yo\N[h7
java代码: 6a4 'xq7
R_1)mPQ^P
C.J`8@a]?
/*Created on 2005-6-17*/ zL:&Q<
package com.adt.action.user; PiMKu|,3
o84UFhm
import java.util.List; gq'>6vOj
/?KtXV>]
import org.apache.commons.logging.Log; pOC% oj
import org.apache.commons.logging.LogFactory; Y5dD|]F|
import org.flyware.util.page.Page; G2.|fp_}pG
+|y*}bG
import com.adt.bo.Result; d<Ggw#}:m
import com.adt.service.UserService; -S"5{ N73
import com.opensymphony.xwork.Action; @#RuSc
0b/ir 2
/** U|gpCy
* @author Joa 'X7%35Y
*/ V0K16#}1gM
publicclass ListUser implementsAction{ JD6aiI!Su
x_*%*H
privatestaticfinal Log logger = LogFactory.getLog >+cSPN'i>
jY7=mAd
(ListUser.class); B:4Ka]{YO
!fY7"E{%%
private UserService userService; %.mEBI=hs
lnS(&`oh\=
private Page page; t\h$&[[l'z
sI_7U^"[
privateList users; F{<5aLaYti
! Tx&vtq
/* 96d~~2p
* (non-Javadoc) HcRa`Sfc]/
* [J^
* @see com.opensymphony.xwork.Action#execute() *?/tO,
R?
*/ s~*}0-lS
publicString execute()throwsException{ HPrq1QpK
Result result = userService.listUser(page); k<a;[_S
page = result.getPage(); /F.Wigv
users = result.getContent(); oM!xz1kVL
return SUCCESS; kb71q:[
} {~SaRB2<'
{_?rh,9q
/** _AFQ >j
* @return Returns the page. C|MQ
$~5:w
*/ hoa7
public Page getPage(){ Tc6:UF
return page; #B8*gFZB
} ~ 3^='o
T*?s@$)m4
/** X'f.Q
* @return Returns the users. !Uh2}ic
*/ M|q~6oM
publicList getUsers(){ *O,H5lwU
return users; F/p,j0S
} /kgeV4]zR
[}OgSP9i
/** Xa," 'r
* @param page Z\~GU*Y.e
* The page to set. )"Q*G/+2Ie
*/ <A>)[u
publicvoid setPage(Page page){ VIC0}LT0R
this.page = page; M*sR3SZ
} N|mJg[j@7
S${Zzt"
/** Kv37s0|g
* @param users %<"}y$J
* The users to set. ZE?f!ifp
*/ gn8|/ev
publicvoid setUsers(List users){ 'OkGReKt
this.users = users; =^&%9X
} !z 53OT!
Tlq-m2]
/** 1TS0X:TCn
* @param userService MP^ d}FL
* The userService to set. J@_ctGv
*/ .pPm~2]z
publicvoid setUserService(UserService userService){ =-KMb`xT
this.userService = userService;
foRD{Hx
} 2o3EHZ+]cm
} )w h%|
YO+{,$
:O-iykXyI
Y ^KTkS0D
D}3T|N
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, lDc-W =X=
}|\d+V2On
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 #3$\Iu
OFk8 >"|
么只需要: @%/]Q<<q
java代码: h.eM
RdlO
\f:z+F!6R
aE"[5*a
<?xml version="1.0"?> H
3@Z.D
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fu[K".
^qGb%! l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 7O5`v(<9n>
O`G/=/GZ
1.0.dtd"> |re}6#TgcT
{@W93=Vq8
<xwork> p;T{i._iL
[XVEBA4GI
<package name="user" extends="webwork- r]@0eb
S! Rc|6y%
interceptors"> ` x8J
\u,}vppz
<!-- The default interceptor stack name lot%N(mB`
a"N4~?US
--> K5Q43e1
<default-interceptor-ref <"N_j]wD
/X"/ha!=&D
name="myDefaultWebStack"/> aNcd`
$0
gr-9l0u
<action name="listUser" W%<LTWOc
>F1kR\!
class="com.adt.action.user.ListUser"> W>_]dPB S/
<param 5 @U<I
vo>d!rVCV
name="page.everyPage">10</param> ^d}gpin
<result l^GP3S
hu_ ^OlF
name="success">/user/user_list.jsp</result> :x.7vZzxs
</action> z>sbr<doa
8Jf.ECQT
</package> [B@'kwD\l
<q*oV
</xwork> Z4<L$i;/jN
-9N@$+T
_Zk{!
,B?~-2cCz
f-DL:@crU
*eI)Z=8
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 )?_#gLrE6
.2d9?p3Y
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。 vEf4HZ&w
+$4(zPs@
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 'z76Sa
x{D yTtX<
=qN2Xg/
zp\8_ U@
S$KFf=0
我写的一个用于分页的类,用了泛型了,hoho P96pm6H_;
5T sU Qc
java代码: ]7-&V-Ct*
DZzN>9<)^
hxce\OuU0h
package com.intokr.util; mF` B#
g^*<f8 ~d
import java.util.List; %X#zj"
DN4$Jva
/** ga?*DI8w
* 用于分页的类<br> /Mb"V5S(W
* 可以用于传递查询的结果也可以用于传送查询的参数<br> }VDqj}is
* I*9e]m"
* @version 0.01 U(~+o
* @author cheng ~y=T5wt
*/ $w"$r$K9K
public class Paginator<E> { Ol4+_n8xj
privateint count = 0; // 总记录数 ]Q[p@gLd
privateint p = 1; // 页编号 *#TUGfwy
privateint num = 20; // 每页的记录数 ~?B;!Csk
privateList<E> results = null; // 结果 l7&$}x-
\u6^Varw
/** 2]% h$f+
* 结果总数 XL7h}
*/ =zwOq(Bh W
publicint getCount(){ mPq$?gdp
return count; [@yV!#2
} bn
|zl!Pq
Da"j E
publicvoid setCount(int count){ V5}B:SUB
this.count = count; Z7 E
}
yf&7P;A
5`f@> r?
/** $-[CG7VgX%
* 本结果所在的页码,从1开始 cQ9q;r`%
* o)'y.-@Q
* @return Returns the pageNo. mKYeD%Pm*
*/ 6e7{Iy
publicint getP(){ N!*_La=TuH
return p; Z@hD(MS(C
} aZ\UrV4,
fu~+8CE.
/** ;5@ t[r
* if(p<=0) p=1 SNY~9:;]f
* WxF:~{
* @param p 7RZh<