问除了行和列之外，如何跟踪标记的偏移位置？

EN

options {
    COMMON_TOKEN_ACTION = true;
}
...
TOKEN_MGR_DECLS : {
    static long offset = 0;
    static void CommonTokenAction(Token t) {
        // Poor-man's re-initialization.
        if ((t.beginLine == 1) && (t.beginColumn == 0)) { offset = 0; }
        offset += t.image.length();
        t.beginLine = (int)(offset >> 32);
        t.endLine = (int)(offset);
    }
}

options {
    TOKEN_EXTENDS = "my.AbstractToken";
    TOKEN_FACTORY = "my.TokenFactory";
}
...

package my;
public abstract class AbstractToken {
    private long offset;
    protected AbstractToken() {
        // The offset hasn't been initialized.
        offset = -1;
    }
    public long getOffset() { return this.offset; }
    void setOffset(long offset) { this.offset = offset; }
}

package my;
public class TokenFactory {
    private static long offset = 0;
    public static Token newToken(int kind, String image) {
        Token token = new Token(kind, image);
        token.setOffset(offset);
        offset += image.length();
    }
}