import java.util.Scanner;

public class Counter {
    public int counter(String inputs, String word) {
        int counter = 0;
        int index =0;
        for (int i = 0; i <= inputs.length() - 1; i++) {
            if ( ( index = inputs.indexOf(word) ) !=-1 ) {
                counter++;
                inputs = inputs.substring(index+word.length());
            }
        }
        return counter;
    }

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        Counter find = new Counter();
        System.out.print("请输入一个字符串：");
        String inputs = input.next();
        System.out.print("请输入要查找的字符:");
        String word = input.next();
        int num = find.counter(inputs, word);
        System.out.println(inputs + "中包含" + num + "个" + word);
    }
}

------解决方案--------------------
Java code
import java.util.Scanner;

public class Counter {
    public int counter(String inputs, String word) {
        int counter = 0;
        int index =0;
//        
//        for (int i = 0; i < inputs.length() - 1; i++) { //要用 <=
//            if (inputs.indexOf(word) == 0) {  //要换成!=-1  !=-1意为找到一次，让count++才有意义
//                counter++;
//                index++;  //仔细看看你的index,哪都没用到，这是毛用...
//            }
//        }
//        return counter;
        
        for (int i = 0; i <= inputs.length() - 1; i++) {
            if ( ( index = inputs.indexOf(word) ) !=-1 ) {
                
                //上句代码意思为若inputs="abcdefgabckabcii"
                //                          word="abc";
                //则每找到一次abc就，让inputs=从c后的那个d开始形成的子串即为defgabckabcii;
                //然后再循环往覆，直到结束.
                
                
//而上面的for(循环其实意思不大)，最好直接用
//            while(( index = inputs.indexOf(word) ) !=-1 ){
//                counter++;
//                inputs = inputs.substring(index+word.length());
//            }
                
            }
        }
        return counter;
    }

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        Counter find = new Counter();
        System.out.print("请输入一个字符串：");
        String inputs = input.next();
        System.out.print("请输入要查找的字符:");
        String word = input.next();
        int num = find.counter(inputs, word);
        System.out.println(inputs + "中包含" + num + "个" + word);
    }
}

------解决方案--------------------
Java code
String str = "aafcfasfqefdsasfaff";  
                //e表示需要匹配的数据，使用Pattern建立匹配模式  
        Pattern p = Pattern.compile("as");  
                //使用Matcher进行各种查找替换操作  
        Matcher m = p.matcher(str);  
        int i = 0;  
        while(m.find()){  
            i++;  
        }  
          
        System.out.println(i);

------解决方案--------------------