我正在尝试制作atrl4 4.6。工作,但我得到了4个错误,这些错误是先进的,我无法通过它们。有人可以帮我吗?也许需要匿名课。
同样是super()错误,我把它放在正确的位置但它拒绝工作。
Yoco.java:34: error: YocoVisitor is abstract; cannot be instantiated
YocoVisitor eval = new YocoVisitor(dictInt, dictProcD);
^ YocoBaseVisitor.java:6: error: YocoBaseVisitor is not abstract and does not override abstract method visitR(RContext) in YocoVisitor public class YocoBaseVisitor extends AbstractParseTreeVisitor<Integer> implements YocoVisitor<Integer> {
^ YocoBaseVisitor.java:12: error: method does not override or implement a method from a supertype
@Override public Integer visitR(HashMap<String, Integer> _dictInt, HashMap<String, YocoParser.ProcDefContext> _dictProcD) {
^ YocoBaseVisitor.java:13: error: call to super must be first statement in constructor
> super();
^ 4 errors
YocoBaseVisitor.java:
// Generated from Yoco.g4 by ANTLR 4.6
import org.antlr.v4.runtime.tree.AbstractParseTreeVisitor;
import org.antlr.v4.runtime.tree.ParseTreeVisitor;
import java.util.HashMap;
public class YocoBaseVisitor extends AbstractParseTreeVisitor<Integer> implements YocoVisitor<Integer> {
HashMap<String, Integer> dictInt = new HashMap<String, Integer>();
HashMap<String, YocoParser.ProcDefContext> dictProcD = new HashMap<String, YocoParser.ProcDefContext>();
@Override public Integer visitR(HashMap<String, Integer> _dictInt, HashMap<String, YocoParser.ProcDefContext> _dictProcD) {
super();
dictInt = _dictInt;
dictProcD = _dictProcD;
}
}
YocoVisitor.java:
{
import org.antlr.v4.runtime.tree.ParseTreeVisitor;
public interface YocoVisitor<Integer> extends ParseTreeVisitor<Integer> {
}
Yoco.java:
public class Yoco {
public static void main(String[] args) throws Exception {
String inputFile = null;
if(args.length > 0)
inputFile = args[0];
InputStream is = System.in;
if (inputFile != null)
is = new FileInputStream(inputFile);
ANTLRInputStream input = new ANTLRInputStream(is);
YocoLexer lexer = new YocoLexer(input);
CommonTokenStream tokens = new CommonTokenStream(lexer);
YocoParser parser = new YocoParser(tokens);
ParseTree tree = parser.r();
System.out.println(tree.toStringTree(parser));
// Hash table for integer variables.
HashMap<String, Integer> dictInt = new HashMap<String, Integer>();
// Hash table for procedure expressions with parameters.
HashMap<String, YocoParser.ProcDefContext> dictProcD = new HashMap<String, YocoParser.ProcDefContext>();
YocoVisitor eval = new YocoVisitor(dictInt, dictProcD);
System.out.println();
eval.visit(tree);
}
}
}
答案 0 :(得分:1)
错误1 - &gt; YocoVisitor是接口,接口无法实例化。 代替 YocoVisitor eval = new YocoVisitor(dictInt,dictProcD); 必须在YocoBaseVisitor中编写和创建相应的构造函数 YocoVisitor eval = new YocoBaseVisitor(dictInt,dictProcD);
错误2 - &gt; super()只能在类的构造函数中作为第一行调用。你已经调用了方法。
错误3 - &gt;方法visitR被覆盖正确检查语法。
希望能解决所有问题。