Java拆分嵌套括號字符串

Question

我有一個像這樣的字符串：

Fields  { name:"aa" type: "bb" paramA { name:"cc" } paramB { other:"ee" other_p:"ff"} paramC { name: "bb" param: "dd" other_params { abc: "xx" xyz:"yy"}} }

我的Java正則表達式代碼提取了paramA，paramB和other_params括號之間的所有內容。 我需要以某種方式在Java對象中構造它，但是我被困在paramC提取中。

Pattern pattern=Pattern.compile("\\w+\\s(\\{([^{]*?)\\})");
Matcher matcher=pattern.matcher(theAboveString);
while (matcher.find()){
System.out.println(matcher.group(1);
}

我的提取代碼

Answer 1

您無法使用正則表達式解析無限嵌套的節點。 （請參閱Chomsky對語言/自動機的分類，或有關使用正則表達式解析HTML的任何stackoverflow問題。）

我已經建立了一個庫，讓您解析這樣的事情。 它甚至有適當的文檔。

http://sourceforge.net/projects/jparser2/

文檔：

http://sourceforge.net/projects/jparser2/files/doc/

Answer 2

這是使用正則表達式進行解析的示例：

String input = "Fields  { name:\"aa\" type: \"bb\" paramA { name:\"cc\" } paramB { other:\"ee\" other_p:\"ff\"} paramC { name: \"bb\" param: \"dd\" other_params { abc: \"xx\" xyz:\"yy\"}} }";
Matcher m = Pattern.compile("\\s*(?:(\\w+)\\s*(?::\\s*(\".*?\")|\\{)|\\})\\s*").matcher(input);
int start = 0;
Deque<String> stack = new ArrayDeque<>();
while (m.find()) {
    if (m.start() != start)
        throw new IllegalArgumentException("Invalid data at " + start);
    if (m.group(2) != null) {
        System.out.println(stack + " : " + m.group(1) + " = " + m.group(2));
    } else if (m.group(1) != null) {
        //System.out.println(m.group(1) + " {");
        stack.addLast(m.group(1));
    } else {
        //System.out.println("}");
        if (stack.isEmpty())
            throw new IllegalArgumentException("Unbalanced brace at " + start);
        stack.removeLast();
    }
    start = m.end();
}
if (start != input.length())
    throw new IllegalArgumentException("Invalid data at " + start);
if (! stack.isEmpty())
    throw new IllegalArgumentException("Unexpected end of text");

產量

[Fields] : name = "aa"
[Fields] : type = "bb"
[Fields, paramA] : name = "cc"
[Fields, paramB] : other = "ee"
[Fields, paramB] : other_p = "ff"
[Fields, paramC] : name = "bb"
[Fields, paramC] : param = "dd"
[Fields, paramC, other_params] : abc = "xx"
[Fields, paramC, other_params] : xyz = "yy"

您應該可以從這里拿走它。

UPDATE

要也支持數字值，請使用此正則表達式：

"\\s*(?:(\\w+)\\s*(?::\\s*(\".*?\"|[-+0-9.eE]+)|\\{)|\\})\\s*"

使用"Layer { name: \\"conv2\\" type: \\"Convolution\\" bottom: \\"norm1\\" top: \\"conv2\\" param { lr_mult: 1 decay_mult: 1 } param { lr_mult: 2 decay_mult: 0 } convolution_param { num_output: 256 pad: 2 kernel_size: 5 group: 2 weight_filler { type: \\"gaussian\\" std: 0.01 } bias_filler { type: \\"constant\\" value: 1 } }}"產生：

[Layer] : name = "conv2"
[Layer] : type = "Convolution"
[Layer] : bottom = "norm1"
[Layer] : top = "conv2"
[Layer, param] : lr_mult = 1
[Layer, param] : decay_mult = 1
[Layer, param] : lr_mult = 2
[Layer, param] : decay_mult = 0
[Layer, convolution_param] : num_output = 256
[Layer, convolution_param] : pad = 2
[Layer, convolution_param] : kernel_size = 5
[Layer, convolution_param] : group = 2
[Layer, convolution_param, weight_filler] : type = "gaussian"
[Layer, convolution_param, weight_filler] : std = 0.01
[Layer, convolution_param, bias_filler] : type = "constant"
[Layer, convolution_param, bias_filler] : value = 1