How I can convert Map to String?-CodePudding

This is my map:

Map<String, Object> params = new HashMap<>();
        params.put("topicRef", "update-123456-78925-new-u1z1w3");
        params.put("parentRef", "update-123456-78925-new-u1z1w3");

        Script script = new Script(ScriptType.INLINE, "painless",
                String.format("ctx._source.parentRef = params.parentRef; ctx._source.topicRef = params.topicRef"),
                params);
        request.setScript(script);

I want to convert my map into a string but I would like to change the pattern for e.g.:

"ctx._source.key = value;ctx._source.key = value"

I want to add to key value a prefix ctx._source.key and a suffix " =" (space and equal), then I would like to separate each entry with a semicolon.

CodePudding user response：

String formattedMap = params.entrySet().
        stream()
        .map(e -> "ctx._source."   e.getKey()   " = "   e.getValue())
        .collect(Collectors.joining(","));

CodePudding user response：

Try something like this:

Map<String, String> yourMap = /*...*/;
StringBuilder bob = new StringBuilder();
yourMap.forEach((key, value) -> bob.append(key).append("=").append(value).append(";"));
String result = bob.toString();

If necessary you could remove the last ; on result via String.concat().

CodePudding user response：

You could stream your Map's entries, then use the map operation to map each entry to the formatted String and ultimately join each element with the collect(Collectors.joining(";")) operation.

Map<String, Object> params = new HashMap<>();
params.put("topicRef", "update-123456-78925-new-u1z1w3");
params.put("parentRef", "update-123456-78925-new-u1z1w3");

String result = params.entrySet().stream()
        .map(entry -> String.format("%s%s%s%s", "ctx._source.", entry.getKey(), " =", entry.getValue()))
        .collect(Collectors.joining(";"));

System.out.println(result);

Here is a link to test the code

CodePudding user response：

String result = params.entrySet()
               .stream()
               .map(x -> "ctx._source."   x.getKey()   " = "   x.getValue())
               .reduce((x, y) -> x   ";"   y).get();