public final native Class<?> getClass()    //返回此 Object 運行時的類
public native int hashCode()    //返回對象的哈希碼
public boolean equals(Object obj)    //判斷其他對象與此對象是否“相等”
protected native Object clone() throws CloneNotSupportedException    //創(chuàng)建并返回此對象的一個副本
public String toString()    //返回對象的字符串表示
protected void finalize() throws Throwable {}    //垃圾回收時調(diào)用該方法
public final native void notify()    //喚醒在此對象監(jiān)視器上等待的單個線程
public final native void notifyAll()    //喚醒在此對象監(jiān)視器上等待的所有線程
public final native void wait(long timeout) throws InterruptedException    //使當(dāng)前對象的線程等待 timeout 時長
public final void wait(long timeout, int nanos) throws InterruptedException    //使當(dāng)前對象的線程等待 timeout 時長，或其他線程中斷當(dāng)前線程
public final void wait() throws InterruptedException    //使當(dāng)前對象的線程等待

public static void main(String[] args) {
    int num1 = 1;
    //將基本數(shù)據(jù)類型裝箱成對象包裝類型，編譯器內(nèi)置方法
    Integer num2 = num1;
    Integer num3 = 3;
    //將對象數(shù)據(jù)類拆箱，該方法是java.lang.Number類中的
    int num4 = num3;
}

package java.lang;
public abstract class Number implements java.io.Serializable {
    public abstract int intValue();　　\\拆箱方法
    public abstract long longValue();
    public abstract float floatValue();
    public abstract double doubleValue();
    public byte byteValue() {
        return (byte)intValue();
    }
    public short shortValue() {
        return (short)intValue();
    }
    private static final long serialVersionUID = -8742448824652078965L;
}

public class BasicNumber {
    public static void main(String args[]) {
        //最大最小值
        int intmax=Integer.MAX_VALUE;
        int intmin=Integer.MIN_VALUE;
        System.out.println(intmax);System.out.println(intmin);
        //String to Int
        String string="55";
        int testInt=100;
        System.out.println(Integer.parseInt(string)+12);//parseInt方法
        System.out.println(Integer.toString(testInt));//toString方法
        System.out.println(String.valueOf(testInt));//valueOf方法
        System.out.println(testInt+"");//+""的隱式轉(zhuǎn)換
        //查看int占用的位數(shù)
        System.out.println(Integer.SIZE);
        //compare方法
        int intbig=17;
        int intsmall=6;
        System.out.println(Integer.compare(intsmall, intbig));
    }
}

public static boolean isDigit(char ch)

public static boolean isLetter(charch)

public static boolean isLowerCase(char ch)

public static boolean isUpperCase(char ch)

public static int toLowerCase(char ch)

public static int toUpperCase(char ch)