java - 符号表实现

Question

我想为IBM360语言设计一个汇编器。所以这里我实现了pass1的符号表。但我在编译期间收到 1 个错误。我无法处理该错误。有人可以指导我吗？？？我的程序在这里...

import java.io.*; 
import java.lang.*; 
import java.util.*;
class Symbol
{
int s_no;
String s_name;
int s_addr;

}
class Literal
{
int literal_no;
String literal_name[];
int literal_addr;
}
class Pass1
 { 
    static String POT[]={"START","END","EQU","DC","DS","USING"};
    static String MOT[]={"L","SR","A","ST"};
    static int POTGET(String instr)
    {
        int i,t;
        for(i=0;i<6;i++)
        {
            t=instr.compareTo(POT[i]);
            if(t==0)
                return(i+1);
        }
        return -1;
    }
    static int MOTGET(String instr)
    {
        int i,t;
        for(i=0;i<4;i++)
        {
            t=instr.compareTo(MOT[i]);
            if(t==0)
                return(i+1);
        }
        return -1;
    }
    public static void main(String args[]) throws Exception 
    { 
    FileReader fr = new FileReader("program1.asm"); 
    BufferedReader br = new BufferedReader(fr); 
    String str,l; 
    String code[][]=new String[50][10];
    int N=0,i,LOC=0,n=0,j;
    System.out.println("Assembly lang program :\n--------------------------");
    while((str = br.readLine()) != null)
    {
        //System.out.println(s); 
        String codearr[]=str.split(" ");
        for(i=0;i<codearr.length;i++)
        {   code[N][i]=codearr[i];  
            System.out.println(codearr[i]);
        }
        N++;
    } 
    fr.close();int k=0;
    Symbol s[]=new Symbol[10];
    boolean flag;
    for(i=0;i<N;i++)
    {
        for(j=0;j<code[i].length;j++)
        {   

            if(code[i][j]!=null && code[i][j]!="\t")
            {
                flag=false;
                int p=POTGET(code[i][j]);
                if(p!=-1)
                    System.out.println( "found IN POT");
                else
                {
                    int m=MOTGET(code[i][j]);
                    if(m!=-1)
                        System.out.println( "found in MOT");
                    else
                        {System.out.println(code[i][j]); flag=true;}
                }
                if(flag)
                {
                if((code[i][j]!="=") && (code[i][j]=",") && (code[i][j]!="F") && (code[i][j].startsWith("\'")!=true))
                {   s[k]= new Symbol();
                    s[k++].s_name=code[i][j];   }
                }
            }
        }
    }
    for(i=0;i<k;i++)
     System.out.println(s[i].s_name);
}
}

错误:

G:\programs>javac Pass1.java
Pass1.java:86: operator && cannot be applied to boolean,java.lang.String
                                if((code[i][j]!="=") && (code[i][j]=",") && (cod
e[i][j]!="F") && (code[i][j].startsWith("\'")!=true))
                                                     ^
1 error

程序1.asm

JOHN START 
     USING * , 15
     SR 1 , 1
     L 1 , FIVE
     A 1 , = F '7'
     ST 1 , TEMP
FIVE DC F '5'
TEMP DS 1F
END

Answer 1

(代码[i][j]=",")

这需要是 == 或 != 而不是 =

编辑:正如 BackSlash 指出的，您应该使用 .equals() 进行字符串比较。