Java，巴拿马项目以及如何处理 Hunspell 'suggest' 结果

Question

我正在试验 Hunspell and how to interact with it using Java Project Panama（Build 19-panama+1-13 (2022/1/18)）。我能够完成一些初始测试，例如创建 handle to Hunspell 并随后使用它来执行拼写检查。我现在正在尝试更精细的东西，让 Hunspell 给我 suggestions 字典中没有的单词。这是我现在拥有的代码：

public class HelloHun {
    public static void main(String[] args) {
        MemoryAddress hunspellHandle = null;
        try (ResourceScope scope = ResourceScope.newConfinedScope()) {
            var allocator = SegmentAllocator.nativeAllocator(scope);

            // Point it to US english dictionary and (so called) affix file
            // Note #1: it is possible to add words to the dictionary if you like
            // Note #2: it is possible to have separate/individual dictionaries and affix files (e.g. per user/doc type)
            var en_US_aff = allocator.allocateUtf8String("/usr/share/hunspell/en_US.aff");
            var en_US_dic = allocator.allocateUtf8String("/usr/share/hunspell/en_US.dic");

            // Get a handle to the Hunspell shared library and load up the dictionary and affix
            hunspellHandle = Hunspell_create(en_US_aff, en_US_dic);

            // Feed it a wrong word
            var javaWord = "koing";

            // Do a simple spell check of the word
            var word = allocator.allocateUtf8String(javaWord);
            var spellingResult = Hunspell_spell(hunspellHandle, word);
            System.out.println(String.format("%s is spelled %s", javaWord, (spellingResult == 0 ? "incorrect" : "correct")));

            // Hunspell also supports giving suggestions for a word - which is what we do next
            // Note #3: by testing this `koing` word in isolation - we know that there are 4 alternatives for this word
            // Note #4: I'm still investigating how to access individual suggestions

            var suggestions = allocator.allocate(10);
            var suggestionCount = Hunspell_suggest(hunspellHandle, suggestions, word);

            System.out.println(String.format("There are %d suggestions for %s", suggestionCount, javaWord));

            // `suggestions` - according to the hunspell API - is a `pointer to an array of strings pointer`
            // we know how many `strings` pointer there are, as that is the returned value from `suggest`
            // Question: how to process `suggestions` to get individual suggestions


        } finally {
            if (hunspellHandle != null) {
                Hunspell_destroy(hunspellHandle);
            }
        }
    }
}

我看到的是对 Hunspell_suggest（从 jextract 创建）的调用成功并返回 (4) 个建议（我从命令行使用 Hunspell 进行了验证）- 所以没问题。

现在对我来说更具挑战性的是如何解压从这个调用返回的 suggestions 元素？我一直在查看各种示例，但其中 none 似乎已经达到了这种程度的详细程度（即使我找到了示例，它们似乎也在使用过时的巴拿马 API）。

所以本质上，这是我的问题：

我如何使用巴拿马 JDK19 API 解压一个结构，据报道该结构包含一个 指向字符串数组的指针 到它们各自的字符串集合？

Answer 1

在此处查看 header：https://github.com/hunspell/hunspell/blob/master/src/hunspell/hunspell.h#L80

/* suggest(suggestions, word) - search suggestions
 * input: pointer to an array of strings pointer and the (bad) word
 *   array of strings pointer (here *slst) may not be initialized
 * output: number of suggestions in string array, and suggestions in
 *   a newly allocated array of strings (*slts will be NULL when number
 *   of suggestion equals 0.)
 */
LIBHUNSPELL_DLL_EXPORTED int Hunspell_suggest(Hunhandle* pHunspell,
                                              char*** slst,
                                              const char* word);

slst 是一个经典的 'out' 参数。也就是说，我们传递一个指向某个值的指针（在本例中为 char**，即字符串数组），该函数将为我们设置该指针，作为 return 多个结果的一种方式。（第一个结果是建议的数量）

在巴拿马，您使用 'out' 参数，方法是分配一个段，该段的布局类型为参数的指针。在本例中 char*** 是指向 char** 的指针，因此布局为 ADDRESS。然后我们将创建的段传递给函数，最后 retrieve/use 函数调用后该段的值，它将填充段内容：

// char***
var suggestionsRef = allocator.allocate(ValueLayout.ADDRESS); // allocate space for an address
var suggestionCount = Hunspell_suggest(hunspellHandle, suggestionsRef, word);
// char** (the value set by the function)
MemoryAddress suggestions = suggestionsRef.get(ValueLayout.ADDRESS, 0);

之后，您可以遍历字符串数组：

for (int i = 0; i < suggestionCount; i++) {
    // char* (an element in the array)
    MemoryAddress suggestion = suggestions.getAtIndex(ValueLayout.ADDRESS, i);
    // read the string
    String javaSuggestion = suggestion.getUtf8String(suggestion, 0);
}

Java，巴拿马项目以及如何处理 Hunspell 'suggest' 结果

Java, project panama and how to deal with Hunspell 'suggest' result

java

hunspell

project-panama