Question

我想从英语句子的解析描述（语法分析的简明形式）生成一个解析树（Java Object）。我使用Java也是如此，需要定义一个有效的树。例如。描述：

    (ROOT (S (NP (PRP I)) (VP (MD would) (VP (VB love) (S (VP (TO to) (VP (VB go) (PRT (RP out)) (PP (IN with) (NP (PRP you)))))))) (. .))

Answer 1

我终于自己解决了这个问题：）

public static Node getParseTree(String[] parseTokens, ArrayList<Node> leafNodeList)
{
    Node top = new Node("TOP");
    Node rest = getParseTree(parseTokens, 2, top, false, leafNodeList);
    return top;
}

public static Node getParseTree(String[] parseTokens, int currIndex, Node lastNode, Boolean closeBrace, ArrayList<Node> leafNodeList)
{
    if(currIndex>=parseTokens.length) return lastNode;
    else if("(".equals(parseTokens[currIndex]))
    {
        Node newNode = lastNode.addChild(parseTokens[currIndex+1]);//The next token is the data for the new node constructed
        return getParseTree(parseTokens, currIndex+2, newNode, false, leafNodeList);
    }
    else if(")".equals(parseTokens[currIndex]))
    {
        if(closeBrace) return getParseTree(parseTokens, currIndex+1, lastNode.getParent(), true, leafNodeList);
        else return getParseTree(parseTokens, currIndex+1, lastNode, true, leafNodeList);
    }
    else //leaf node 
    {
        Node newNode = lastNode.addChild(parseTokens[currIndex]);
        leafNodeList.add(newNode);
        return getParseTree(parseTokens, currIndex+2, lastNode.getParent(), true, leafNodeList);
    }       
}

Node test(String parseDesc)
{
        parseDesc = parseDesc.replace("(", " ( ");
        parseDesc = parseDesc.replace(")", " ) ");
        String[] parseDescTokens = parseDesc.trim().split("\\s+");
        Node treeReqd = getParseTree(parseDescTokens, leafNodes);// Required Tree
}

从解析描述生成解析树

1 个答案: