20.鏁扮粍鍒楄〃:ArrayList鍔ㄦ佹暟緇勫垪琛紝鏄竴涓被搴擄紝瀹氫箟鍦╦ava.uitl鍖呬腑錛屽彲鑷姩璋冭妭鏁扮粍鐨勫ぇ灝忋?
21.class綾?object綾諱腑鐨刧etclass鏂規硶榪斿洖ckass綾誨瀷鐨勪竴涓疄渚嬶紝紼嬪簭鍚姩鏃跺寘鍚湪main鏂規硶鐨勭被浼氳鍔犺澆錛岃櫄鎷熸満瑕佸姞杞戒粬闇瑕佺殑鎵鏈夌被錛屾瘡涓涓姞杞界殑綾婚兘瑕佸姞杞藉畠闇瑕佺殑綾匯?
銆銆
銆銆22.class綾諱負緙栧啓鍙姩鎬佹搷綰礿ava浠g爜鐨勭▼搴忔彁渚涗簡寮哄ぇ鐨勫姛鑳藉弽灝勶紝榪欓」鍔熻兘涓篔avaBeans鐗瑰埆鏈夌敤錛屼嬌鐢ㄥ弽灝凧ava鑳芥敮鎸乂B紼嬪簭鍛樹範鎯嬌鐢ㄧ殑宸ュ叿銆?
銆銆
銆銆鑳藉鍒嗘瀽綾昏兘鍔涚殑紼嬪簭鍙弽灝勫櫒錛孞ava涓彁渚涙鍔熻兘鐨勫寘鍙獼ava.lang.reflect鍙嶅皠鏈哄埗鍗佸垎寮哄ぇ銆?
銆銆
銆銆1錛夊湪榪愯鏃跺垎鏋愮被鐨勮兘鍔涖?
銆銆
銆銆2錛夊湪榪愯鏃舵帰瀵熺被鐨勫璞°?
銆銆
銆銆3錛夊疄鐜伴氱敤鏁扮粍鎿嶇旱浠g爜銆?
銆銆
銆銆4錛夋彁渚涙柟娉曞璞°?
銆銆
銆銆鑰屾鏈哄埗涓昏閽堝鏄伐鍏瘋呰屼笉鏄簲鐢ㄥ強紼嬪簭銆?
銆銆
銆銆鍙嶅皠鏈哄埗涓殑鏈閲嶈鐨勯儴鍒嗘槸鍏佽浣犳鏌ョ被鐨勭粨鏋?鐢ㄥ埌鐨凙PI鏈?
銆銆
銆銆java.lang.reflect.Field 榪斿洖瀛楁銆?
銆銆
銆銆java.reflect.Method 榪斿洖鏂規硶銆?
銆銆
銆銆java.lang.reflect.Constructor 榪斿洖鍙傛暟銆?
銆銆
銆銆鏂規硶鎸囬拡:java娌℃湁鏂規硶鎸囬拡錛屾妸涓涓柟娉曠殑鍦板潃浼犵粰鍙︿竴涓柟娉曪紝鍙互鍦ㄥ悗闈㈣皟鐢ㄥ畠錛岃屾帴鍙f槸鏇村ソ鐨勮В鍐蟲柟妗堛?
銆銆
銆銆23.鎺ュ彛(Interface)璇存槑綾昏鍋氫粈涔堣屼笉鎸囧畾濡備綍鍘誨仛錛屼竴涓被鍙互瀹炵幇涓涓垨澶氫釜interface銆?
銆銆
銆銆24.鎺ュ彛涓嶆槸涓涓被錛岃屾槸瀵圭鍚堟帴鍙h姹傜殑綾葷殑涓濂楄鑼冦?
銆銆
銆銆鑻ュ疄鐜頒竴涓帴鍙i渶瑕?涓楠?
銆銆
銆銆1錛夊0鏄庣被闇瑕佸疄鐜扮殑鎸囧畾鎺ュ彛銆?
銆銆
銆銆2錛夋彁渚涙帴鍙d腑鐨勬墍鏈夋柟娉曠殑瀹氫箟銆?
銆銆
銆銆澹版槑涓涓被瀹炵幇涓涓帴鍙i渶瑕佷嬌鐢╥mplements 鍏抽敭瀛?
銆銆
銆銆class actionB implements Comparable 鍏禷ctionb闇瑕佹彁渚汣ompareTo鏂規硶錛屾帴鍙d笉鏄被錛屼笉鑳界敤new瀹炰緥鍖栦竴涓帴鍙c?
銆銆
銆銆25.涓涓被鍙湁涓涓秴綾伙紝浣嗕竴涓被鑳藉疄鐜板涓帴鍙c侸ava涓殑涓涓噸瑕佹帴鍙o細Cloneable
銆銆
銆銆26.鎺ュ彛鍜屽洖璋?緙栫▼涓涓父鐢ㄧ殑妯″紡鏄洖璋冩ā寮忥紝鍦ㄨ繖縐嶆ā寮忎腑浣犲彲浠ユ寚瀹氬綋涓涓壒瀹氭椂闂村彂鐢熸椂鍥炶皟瀵硅薄涓婄殑鏂規硶銆?
銆銆
銆銆渚?ActionListener 鎺ュ彛鐩戝惉銆?
銆銆
銆銆綾諱技鐨凙PI鏈?
銆銆java.swing.JOptionPane
銆銆java.swing.Timer
銆銆java.awt.Tookit
銆銆
銆銆27.瀵硅薄clone:clone鏂規硶鏄痮bject涓涓繚鎶ゆ柟娉曪紝榪欐剰鍛崇潃浣犵殑浠g爜涓嶈兘綆鍗曠殑璋冪敤瀹冦?
銆銆
銆銆28.鍐呴儴綾?涓涓唴閮ㄧ被鐨勫畾涔夋槸瀹氫箟鍦ㄥ彟涓涓唴閮ㄧ殑綾匯?
銆銆
銆銆鍘熷洜鏄?
銆銆
銆銆1錛変竴涓唴閮ㄧ被鐨勫璞¤兘澶熻闂垱寤哄畠鐨勫璞$殑瀹炵幇錛屽寘鎷鏈夋暟鎹?
銆銆
銆銆2錛夊浜庡悓涓涓寘涓殑鍏朵粬綾繪潵璇達紝鍐呴儴綾昏兘澶熼殣钘忚搗鏉ャ?
銆銆
銆銆3錛夊尶鍚嶅唴閮ㄧ被鍙互寰堟柟渚跨殑瀹氫箟鍥炶皟銆?
銆銆
銆銆4錛変嬌鐢ㄥ唴閮ㄧ被鍙互闈炲父鏂逛究鐨勭紪鍐欎簨浠墮┍鍔ㄧ▼搴忋?
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銆銆29.浠g悊綾?proxy):
銆銆
銆銆1錛夋寚瀹氭帴鍙h姹傛墍鏈変唬鐮?
銆銆
銆銆2錛塷bject綾誨畾涔夌殑鎵鏈夌殑鏂規硶(toString equals)
銆銆
銆銆30.鏁版嵁綾誨瀷:Java鏄己璋冪被鍨嬬殑璇█錛屾瘡涓彉閲忛兘蹇呴』鍏堢敵鏄庡畠閮界被鍨嬶紝java涓誨叡鏈?涓熀鏈被鍨?4縐嶆槸鏁村瀷錛?縐嶆槸嫻偣鍨嬶紝涓縐嶆槸瀛楃鍨嬶紝琚敤浜嶶nicode緙栫爜涓殑瀛楃錛屽竷灝斿瀷銆?/p>
銆銆2.鑱旀帴鏁版嵁婧愩?br />聽 Connection con
聽 浠ヤ笅浠婚夊叾涓
聽 con = DriverManager.getConnection(<url>)
聽 con = DriverManager.getConnection(<url>,<proporties>)
聽 con = DriverManager.getConnection(<url>,<user>,<password>)
銆銆3.鎵ц
聽 Statement stmt=con.creatStatement();
聽 ----鎵ц瀛樺偍榪囩▼錛歴tmt.execute(<String sql>)
聽 ----浠ユ壒澶勭悊鏂瑰紡鎵ц澶氫釜璇彞錛歴tmt.executeBatch()
聽 ----鏇存柊澶勭悊錛毬犅?int updateCount=stmt.executeUpdate(<String聽 sql>)
聽 ----鏌ヨ聽聽聽聽聽聽聽聽聽聽聽聽 ResultSet rs=stmt.executeQuery(<String sql>)
聽聽聽聽聽聽聽 甯哥敤鐨勬槸:聽 while (rs.next())
聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽 {}
銆銆鍒╃敤 . PrepairedStatement
聽聽 浼樼偣錛氫笉闇閲嶆柊鍦ㄧ敓鎴愶紝鍙淇敼鍙傛暟灝卞彲浠ヤ簡錛?br />聽聽 e.g.聽 PrepairedStatement pstmt1
聽聽 pstmt1=con.PrepairedStatement("select * from tableName where聽 a=? and b=?")
聽聽 pstmt1.setString(text1.getText,text2.getText)
聽聽 ResultSet聽 rs=pstmt1.executeQuery();
銆銆鍒╃敤 ResultSetMetaData
聽聽聽 瑕佸彇寰楁暟鎹〃涓殑瀛楁鏁扮洰錛岀被鍨嬬瓑錛屽彲浠ュ埄鐢≧esult鐨刧etMetaData(),榪斿洖緇撴灉鏄互ResultSetMetaData瀵硅薄淇濆瓨銆?br />聽聽聽 e.g.
聽聽聽 ResultSet rs =stmt.getResultSet()
聽聽聽 ResultSetMetaData rsmd=rs.getMetaData();
聽聽聽 //瀛楁鏁扮洰錛?br />聽聽聽 int columeCount=rsmd.getColumnCount()
聽聽聽聽聽聽聽聽 for (i=1;i<=columnCount;i++)
聽聽聽聽聽聽聽聽聽聽 {
聽聽聽聽聽聽聽聽聽聽聽聽聽聽 System.out.println(rsmd.getClumnName())
聽聽聽聽聽聽聽聽聽聽聽聽聽 }