example04_convert.java

java课程设计教材上的程例题序代码

package example;

//该程序实现有关类型之间的转换
public class Example04_Convert
{
	public static void main(String[] args)
	{
		//byte[] to String
		{
			byte[] bytes={'H','e','l','l','o','!'};
			String string=new String(bytes);
			System.out.println(string);
		}
		
		//String to byte[]
		{
			String string="Hello!";
			byte[] bytes=string.getBytes();
			for (int i=0;i<bytes.length;i++)
			{
				System.out.print((char)bytes[i]);
			}
			System.out.println();
		}
		
		//char[] to String
		{
			char[] chars={'H','o','w',' ','a','r','e',' ','y','o','u','?'};
			String string=new String(chars);
			System.out.println(string);
		}
		
		//String to char[]
		{
			//method 1
			String string="How are you?";
			char[] chars=string.toCharArray();
			System.out.println(chars);
			//method 2
			chars=new char[3];
			string.getChars(0,3,chars,0);
			System.out.println(chars);
		}
		
		//String to StringBuffer
		{
			String string=new String("World");
			StringBuffer strbuff=new StringBuffer(string);
			System.out.println(strbuff);
		}
		
		//StringBuffer to String
		{
			StringBuffer strbuff=new StringBuffer("World");
			//method 1
			String string=strbuff.toString();
			System.out.println(string);
			//method 2
			string=new String(strbuff);
			System.out.println(string);
		}
		
		//基本数据类型, String and 包装类
		{
			//boolean
			boolean boolb=true;
			Boolean boolp=new Boolean(boolb);
					boolp=new Boolean("true");
					boolp=Boolean.valueOf(boolb);
					boolp=Boolean.valueOf("true");
			boolb=boolp.booleanValue();
			System.out.println(boolp.toString());
			System.out.println(Boolean.toString(boolb));
			
			//byte
			byte byteb=10;
			Byte bytep=new Byte(byteb);
				 bytep=new Byte("10");
				 bytep=Byte.valueOf("10");
			byteb=bytep.byteValue();//shortValue();intValue();longValue();floatValue();doubleValue();
			byteb=Byte.parseByte("10");
			System.out.println(bytep.toString());
			System.out.println(Byte.toString(byteb));
			
			//char
			char charb='字';
			Character charp=new Character(charb);
			charb=charp.charValue();
//			int intn=Character.getNumericValue('字');
			System.out.println(charp.toString());
			System.out.println(Character.toString(charb));
			
			//short
			short shortb=100;
			Short shortp=new Short(shortb);
				  shortp=new Short("100");
				  shortp=Short.valueOf("100");
			shortb=shortp.shortValue();//byteValue();intValue();longValue();floatValue();doubleValue();
			shortb=Short.parseShort("100");
			System.out.println(shortp.toString());
			System.out.println(Short.toString(shortb));
			
			//int
			int intb=10000;
			Integer intp=new Integer(intb);
					intp=new Integer("10000");
					intp=Integer.valueOf("10000");
			intb=intp.intValue();//byteValue();shortValue();longValue();floatValue();doubleValue();
			intb=Integer.parseInt("10000");
			System.out.println(intp.toString());
			System.out.println(Integer.toString(intb));//toBinaryString(int);toOctalString(int);toHexString(int);
			System.out.println(Integer.toString(intb,16));
			
			//long
			long longb=1000000;
			Long longp=new Long(longb);
				 longp=new Long("1000000");
				 longp=Long.valueOf("1000000");
			longb=longp.longValue();//byteValue();shortValue();intValue();floatValue();doubleValue();
			longb=Long.parseLong("1000000");
			System.out.println(longp.toString());
			System.out.println(Long.toString(longb));//toBinaryString(long);toOctalString(long);toHexString(long);
			System.out.println(Long.toString(longb,16));
			
			//float
			float floatb=10.05f;
			Float floatp=new Float(floatb);
				  floatp=new Float("10.05f");
				  floatp=Float.valueOf("10.05f");
			floatb=floatp.floatValue();//byteValue();shortValue();intValue();longValue();doubleValue();
			floatb=Float.parseFloat("10.05f");
			System.out.println(floatp.toString());
			System.out.println(Float.toString(floatb));
			
			//double
			double doubleb=1234.56789;
			Double doublep=new Double(doubleb);
				   doublep=new Double("1234.56789");
				   doublep=Double.valueOf("1234.56789");
			doubleb=doublep.doubleValue();//byteValue();shortValue();intValue();longValue();floatValue();
			doubleb=Double.parseDouble("10.05f");
			System.out.println(doublep.toString());
			System.out.println(Double.toString(doubleb));
		}
	}
}