String 与primitive主数据类型的转换

public class MyString//将primitive主数据类型换为String
{
	public static void main(String [] args)
	{
		double d=42.5;
		String doubleString=""+d;
		System.out.println(doubleString);
		String doubleString2=Double.toString(d);
		System.out.println(doubleString2);
	}
}

public class Transport//将String换为主数据类型
{
	public static void main(String [] args)
	{
		String s="2";
		int x=Integer.parseInt(s);
		double d=Double.parseDouble("420.4");
		boolean b=new Boolean("true").booleanValue();
		System.out.print(x+" "+d+" "+b);
		String t="two";
		int y=Integer.parseInt(t);
	}
}