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public static int binarySerach(byte[] a,int key)
public static int binarySerach(double[] a,double key) public static int binarySerach(Object[] a, Object key)
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public static boolean equals(byte[] a, byte[] b) public static boolean equals(double[] a, double[] b) public static boolean equals(Object[] a, Object [] b)
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public static void fill(byte[] a, byte val) public static void fill(double[] a, double val) public static void fill(Object[] a, Object val) ½«Êý×éaÖеÄËùÓÐÔªËØÌî³äΪval
public static void fill(byte[] a, int fromIndex,int toIndex,byte val) public static void fill(double[] a, int fromIndex,int toIndex ,double val) public static void fill(Object[] a, int fromIndex,int toIndex, Object val) ½«Êý×éÖÐaÖÐ,´ÓË÷ÒýfromIndexµ½toIndexµÄËùÓÐÔªËØÌî³äΪval
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public static void sort(byte[] a) public static void sort(int[] a) public static void sort(long[] a) public static void sort (double[] a, byte val) public static void sort (Object[] a)
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public static void sort(byte[] a, int fromIndex,int toIndex) public static void sort(int[] a, int fromIndex,int toIndex) public static void sort(long[] a, int fromIndex,int toIndex) public static void sort (double[] a, int fromIndex,int toIndex) public static void sort (Object[] a, int fromIndex,int toIndex)
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static System. arraycopy(Object[] src,int srcPos,Object dest,int destPos,int length) ´ÓÔ´¶ÔÏóÊý×ésrcµÄsrcPosλÖÿªÊ¼È¡³¤¶ÈΪlength¸öÔªËØ¿½±´µ½Ä¿±êÊý×éÖÐ dest ÖУ¬²¢´ÓdestPostλÖÿªÊ¼´æ·Å¡£ ¶þ£®±ê×¼ÊäÈëÊä³öÓйصÄÊôÐÔ¼°Æä·½·¨£º
static PrintStream err; static InputStream in; static PrintStream out; static System.out.print(Object obj); Êä³öÈÎÒâ¶ÔÏóµÄ×Ö·û´®±íʾ static System.out.println(Object obj); Êä³öÈÎÒâ¶ÔÏóµÄ×Ö·û´®±íʾ,²¢»»ÐС£ Èý£®ÏµÍ³Ê±¼ä static System.currentTimeMillis(); »ñµÃµ±Ç°Ê±¼äµÄºÁÃëÊý
java.math.BigIntegerÀà
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public BigInteger abs(); ·µ»Ø¾ø¶ÔÖµ
public BigInteger add(BigInteger val); ¼Ó public BigInteger subtract(BigInteger val); ¼õ public BigInteger multiply(BigInteger val); ³Ë public BigInteger divide(BigInteger val); ³ý public BigInteger max(BigInteger val); ×î´óÖµ public BigInteger min(BigInteger val); ×îСֵ public BigInteger mod(BigInteger val); È¡Ä£ public BigInteger pow(BigInteger val); ÃÝ public int intValue(); ת»»Îªint ·µ»Ø public long longValue();ת»»Îªlong ·µ»Ø
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TimerÀàͨ¹ýºǫ́Ï̵߳÷¶ÈÈÎÎñ£¬Ê¹ÈÎÎñµÃÒÔÖ´ÐС£ ¶þ£®TimerÀà ³£Óù¹Ôì·½·¨£º Timer() Timer(String name) ³£ÓòÙ×÷·½·¨£º schedule(TimerTask task,int delayRunTime,int interval) task ÈÎÎñÀà»òÆä×ÓÀà delayRunTime µÚÒ»´ÎÔËÐÐʱ¼ä(Ïà¶ÔÓÚ·½·¨¸Ã·½·¨µ÷Óúó), ms
interval ÈÎÎñ±»Öظ´Ö´ÐеÄʱ¼ä¼ä¸ô,ms cancel();//ֹͣʱÖÓ
Èý£®TimerTaskÀà ³£Óù¹Ôì·½·¨£º TimerTask£¨int maxCounter,Timer aTimer£© maxCounterÈÎÎñ±»Ö´ÐеÄ×Ü´ÎÊý aTimer Timer¶ÔÏó
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1. Ê×ÏÈ´ÓTimerTaskÀ©Õ¹Ò»¸ö×Ô¼ºµÄÀà
class MyTimerTask extends TimerTask{ private int maxNumberOfTimesToRun=0;//ÈÎÎñ±»Ö´ÐеÄ×Ü´ÎÊý private Timer myTimer=null;
public MyTimerTask(int maxCounter,Timer aTimer){ super(); maxNumberOfTimesToRun= maxCounter; myTimer=aTimer } //¸²¸Ç¸¸ÀàµÄ·½·¨ public void run(){ //ÒªÖ´ÐеÄÈÎÎñ´úÂë } }
2. Æô¶¯TimerÔËÐÐ
2.1. »ñµÃÒ»¸öTimerʵÀý 2.2. »ñµÃTimerTaskʵÀý
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1.À©Õ¹TimerTask
import java.util.*;
class MyTimerTask extends TimerTask{
private int maxNumberOfTimesToRun=0;//ÈÎÎñ±»Ö´ÐеÄ×Ü´ÎÊý private int runCounter=0;//ÈÎÎñÒѾ±»µ÷¶ÈµÄ´ÎÊý private Timer myTimer=null;
private Random rand=new Random();//ÓÃÓÚ²úÉúËæ»úÊý£¬Ä£ÄâÈËÎï public MyTimerTask(int maxCounter,Timer aTimer){
super();
maxNumberOfTimesToRun= maxCounter;
}
myTimer=aTimer;
//¸²¸Ç¸¸ÀàµÄ·½·¨
public void run(){ }
2Æô¶¯µ÷¶ÈÆ÷
public class RunTask {
//ÒªÖ´ÐеÄÈÎÎñ´úÂë
if(runCounter cancel();//Í£Ö¹ÈÎÎñ myTimer.cancel();//ֹͣʱÖÓ long currentTime=System.currentTimeMillis(); Date dt=new Date(currentTime); System.out.print(dt+\); System.out.println(rand.nextInt(999999));//²úÉúÒ»¸öËæ»úÊý runCounter++; System.out.println(\ÈÎÎñÒѾȫ²¿Íê³É£¡\); } } public static void main(String[] args){ Timer myTimer=new Timer();//ʵÀý»¯Timer //ʵÀý»¯TimerTask,ÈÎÎñ±»Ö´ÐÐ5´Î MyTimerTask task=new MyTimerTask(5,myTimer); myTimer.schedule(task,0, 3000);//Æô¶¯Ê±ÖÓ } ½Ó¿Ú java.lang. CharSequence ʵÏÖÁËÕâ¸ö½Ó¿ÚµÄËùÓÐÀࣺCharBuffer, String, StringBuffer, StringBuilder ¶ÔÓÚʹÓÃÀàÐÍCharSequence×÷Ϊ²ÎÊýµÄÈκεط½¿ÉÒÔÖ±½Ó½«ÀàÐÍCharBuffer, String, StringBuffer, StringBuilder´«µÝ¸øÕâ¸ö²ÎÊý¡£ÀýÈ磺 ÀýÈ磺FileWriter Àà×·¼ÓÄÚÈݵķ½·¨£º fw.append(CharSequence c) ¿ÉÒÔÕâÑù£ºfw.append(¡°´óÁ¬ÊÇÒ»¸öÃÀÀöµÄº£±õ³ÇÊС±);