java无法从静态上下文中引用非静态_[求助]无法从静态上下文中引用非静态方法...

[求助]无法从静态上下文中引用非静态方法

小错能自己改 就是

LetterFrequencyDetector.java:53: 无法从静态上下文中引用非静态 方法 buildAlphabet

()

buildAlphabet( );

^

LetterFrequencyDetector.java:54: 无法从静态上下文中引用非静态 方法 removeNonLett

ers(java.lang.String)

ArrayList a=removeNonLetters(args[0]);

^

LetterFrequencyDetector.java:55: 无法从静态上下文中引用非静态 方法 calculateFreq

uencies(java.util.ArrayList)

calculateFrequencies(a);

^

LetterFrequencyDetector.java:56: 无法从静态上下文中引用非静态 方法 displayFreque

ncies()

displayFrequencies();

实在不知道怎么改了..

代码：

import java.util.*;

public class LetterFrequencyDetector{

ArrayList Alphabet = new ArrayList( );

ArrayList reAlphabet=new ArrayList( );

ArrayList Frequency=new ArrayList();

int[] count=new int[26];

public ArrayList buildAlphabet( ){

for(int i=97;i<=122;i++){

Alphabet.add((char)i);

}

return Alphabet;

}

public ArrayList removeNonLetters(String s){

s=s.toLowerCase();

for(int i=0;i

int c=s.charAt(i);

if(c>=97&&c<=122)

count[c-97]++;

}

for(int j=0;j<26;j++){

if(count[j]==0)

reAlphabet.remove(j);

}

return reAlphabet;

}

public ArrayList calculateFrequencies(ArrayList a){

Frequency.size=reAlphabet.size;

for(int i=0;i<26;i++){

if(count[i]!=0)

Frequency.add(count[i]);

}

return Frequency;

}

public void displayFrequencies(){

for(int i=0;i

System.out.print(reAlphabet.get(i)+"--"+Frequency.get(i));

for(int j=0;j

System.out.print("*");

}

System.out.println();

}

}

public static void main(String args[]){

buildAlphabet( );

ArrayList a=removeNonLetters(args[0]);

calculateFrequencies(a);

displayFrequencies();

}

}