●キーワードが含まれるindex番号を取得
indexOf()

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public class indexOfDemo {
public static void main(String args[]){
String x = "AB C DE hi XYZ 123456789";
int point = x.indexOf("X");
System.out.println(point);
String s = x.substring(point);
System.out.println(s);

point = x.indexOf("6", 11);
System.out.println(point);
s = x.substring(point);
System.out.println(s);
}
}
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●文字列から指定した部分を抜き出す
substring()

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public class substringDemo {
public static void main(String args[]){
String s1 = "ABCDEDGHIJKLM";
//
System.out.println(s1);
System.out.println(s1.substring(2, 5));
}
}
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●文字列を指定された文字で分割する
split()

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public class splitDemo {
public static void main(String args[]){
String x = "AB,C,DE,hi,XYZ";
String y[];
y = x.split(",");
for(int i = 0; i < y.length; i++){
System.out.println(y[i]);
}
}
}
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