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Java 8でJSONArrayを反復処理する方法

for loopを使用してJSONArray内の要素を反復処理する次のコードがあります。

import org.Apache.log4j.Logger;
import org.json.JSONArray;
import org.json.JSONObject;

import Java.util.stream.IntStream;
    public class Pmt {
    private String[] patchInformation_svnRevisionpublic;
    private final Logger logger = Logger.getLogger(Pmt.class.getName());

        private static final String COMMITS_IN_PATCH_IDENTIFIER = "patchInformation_svnRevisionpublic";  //key used to identify the commits in a patch from JSON response received from PMT
        private static final String KEY_STRING = "name";
        private static final String VALUE_STRING = "value";

         public String[] getPublicGitCommitHashes(JSONArray jsonArray) {

            for (int i = 0; i < jsonArray.length(); i++) {
                JSONObject jsonObject = (JSONObject) jsonArray.get(i);
                String tempName = (String) jsonObject.get(KEY_STRING);
                if (tempName.equals(COMMITS_IN_PATCH_IDENTIFIER)) {
                    JSONArray tempCommitsJSONArray = (JSONArray) jsonObject.get(VALUE_STRING);
                    //initializing the patchInformation_svnRevisionpublic array
                    patchInformation_svnRevisionpublic = new String[tempCommitsJSONArray.length()];
                    // for ommiting the white spaces at the begingin and end of the commits
                    IntStream.range(0, tempCommitsJSONArray.length()).forEach(j -> patchInformation_svnRevisionpublic[j] = ((String) tempCommitsJSONArray.get(j)).trim());

                    logger.info(" The commits hashes obtained from WSO2 PMT are successfully saved to an array");

                    System.out.println("The commit Ids are");
                    //            for printing all the commits ID associated with a patch
                    IntStream.range(0, patchInformation_svnRevisionpublic.length).mapToObj(i1 -> patchInformation_svnRevisionpublic[i1]).forEach(System.out::println);
                    System.out.println();
                    break;
                }
            }
            //to prevent from internaal representation by returning referecnce to mutable object
            String clonedPatchInformation_svnRevisionpublic[] = patchInformation_svnRevisionpublic.clone();
            return clonedPatchInformation_svnRevisionpublic;
        }
    }

Java 8やforEachなどのstreams APIの新機能を使用して同じタスクを実行するにはどうすればよいですか。前もって感謝します

javajsonforeachjava-8java-stream
8
Kasun Siyambalapitiya

これは、Java 8ストリームAPIと同等です。

private static final String COMMITS_IN_PATCH_IDENTIFIER = "patchInformation_svnRevisionpublic";  //key used to identify the commits in a patch from JSON response received from PMT
private static final String KEY_STRING = "name";
private static final String VALUE_STRING = "value";

public List<String> getCommitIds (JSONArray array) {
     return arrayToStream(array)
            .map(JSONObject.class::cast)
            .filter(o -> o.get(KEY_STRING).equals(COMMITS_IN_PATCH_IDENTIFIER))
            .findFirst()
            .map(o -> (JSONArray) o.get(VALUE_STRING))
            .map(Main::arrayToStream)
            .map(commits ->
                    commits.map(Object::toString)
                            .map(String::trim)
                            .collect(Collectors.toList())
            )
            .orElseGet(Collections::emptyList);
}

@Nonnull
private static Stream<Object> arrayToStream(JSONArray array) {
    return StreamSupport.stream(array.spliterator(), false);
}
9
Dmitry Zvorygin