Java学习笔记——String类型转换

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上代码：

package cn.stringtoobj;

public class TypeConversion {

    public static void main(String[] args) {
        //将String转int
        String str = "123";
        int[] ints = new int[3];
        ints[0] = Integer.parseInt(str);
        ints[1] = Integer.valueOf(str);
        ints[2] = new Integer(str);
        print(ints);
        //String转byte
        byte[] bytes = new byte[3];
        bytes[0] = Byte.parseByte(str);
        bytes[1] = Byte.valueOf(str);
        bytes[2] = new Byte(str);
        print(bytes);
        //String转short
        short[] shorts = new short[3];
        shorts[0] = Short.parseShort(str);
        shorts[1] = Short.valueOf(str);
        shorts[2] = new Short(str);
        print(shorts);
        //String转long
        long[] longs = new long[3];
        longs[0] = Long.parseLong(str);
        longs[1] = Long.valueOf(str);
        longs[2] = new Long(str);
        print(longs);
        //String转double
        double[] doubles = new double[3];
        doubles[0] = Double.parseDouble(str);
        doubles[1] = Double.valueOf(str);
        doubles[2] = new Double(str);
        print(doubles);
        //String转float
        float[] floats = new float[3];
        floats[0] = Float.parseFloat(str);
        floats[1] = Float.valueOf(str);
        floats[2] = new Float(str);
        print(floats);
        //String转boolean
        str = "true";
        boolean[] booleans = new boolean[3];
        booleans[0] = Boolean.parseBoolean(str);
        booleans[1] = Boolean.valueOf(str);
        booleans[2] = new Boolean(str);
        print(booleans);
        //String转byte[]
        byte[] bytes2 = str.getBytes();
        print(bytes2);
        //String转char[]
        char[] dstchars =new char[str.length()];
        str.getChars(0, str.length(), dstchars, 0);
        print(dstchars);
        //Object转String
        Object[] obj = new Object[5];
        str = String.valueOf(obj);
        System.out.println(str);
        str = String.valueOf(dstchars);
        System.out.println(str);
    }
    private static void print(char[] dstchars) {
        for (char i : dstchars) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(boolean[] booleans) {
        for (boolean i : booleans) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(float[] floats) {
        for (float i : floats) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(double[] doubles) {
        for (double i : doubles) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(long[] longs) {
        for (long i : longs) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(short[] shorts) {
        for (short i : shorts) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(int[]ints){
        for (int i : ints) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
    private static void print(byte[]bytes){
        for (byte i : bytes) {
            System.out.print(i +" ");
        }
        System.out.println();
    }
}