java之字符串学习记录
public class StringDemo {
public static void main(String[] args) {
//静态初始化字符串
String s1 = "hello china!";
String s3 = "Hello China!";
System.out.println(s1);
//动态初始化字符串
String s2 = new String("hello china!,china,china");
String s4 = new String("hello china!");
String s5 = "hello Japan";
String s6 = "Hey,"; //Hey,hello china!
String s7 = "北京|上海|南京|武汉|成都";
System.out.println(s1==s3);//true
System.out.println(s2==s4);//false
System.out.println(s2.equals(s4));//true
System.out.println(s1.charAt(6));//获得字符'c'
//返回0：s1==s5, 负数 s1<s5 正数 s1>s5
System.out.println(s1.compareTo(s5));
System.out.println(s6.concat(s1));
System.out.println(s6+s1);
System.out.println(s1.contains("china"));//true
System.out.println(s1.contains("japan"));//false
byte[] arr = s1.getBytes();
System.out.println(s2.indexOf("china"));
System.out.println(s2.lastIndexOf("china"));
String[] citys = s7.split("\\|");
for(int i=0;i<citys.length;i++)
{
System.out.println(citys[i]);
}
StringTokenizer st = new StringTokenizer(s7,"|");
System.out.println("-------------------");
while(st.hasMoreElements())
{
System.out.println(st.nextElement());
}
System.out.println(s1.substring(6,s1.length()-1));
System.out.println(s1.toUpperCase());
System.out.println(s3.toLowerCase());
}
}