For the following code
public class GsonTest
{
public static void main(String[] args)
{
Gson gson = new Gson();
SortedMap<Long, Number> map = new TreeMap<>();
map.put(System.currentTimeMillis(), 200l);
String json2 = gson.toJson(map);
System.out.println(json2);
}
}
I get the following output
{"1484140989691":200}
Is it possible that primitive keys are not deserialized as Strings and that I could have the following output?
{1484140989691:200}
Many thanks
{1484140989691:200}
Is not valid JSON.
Reference
An object structure is represented as a pair of curly brackets
surrounding zero or more name/value pairs (or members). A name is a
string. A single colon comes after each name, separating the name
from the value. A single comma separates a value from a following
name. The names within an object SHOULD be unique.
object = begin-object [ member *( value-separator member ) ]
end-object
member = string name-separator value
Related
I am using the following code snippet to serialise a dynamic model of a project to a string (which is eventually exported to a YAML file).
dynamic exportModel = exportModelConvertor.ToDynamicModel(project);
var serializerBuilder = new SerializerBuilder();
var serializer = serializerBuilder.EmitDefaults().DisableAliases().Build();
using (var sw = new StringWriter())
{
serializer.Serialize(sw, exportModel);
string result = sw.ToString();
}
Any multi-line strings such as the following:
propertyName = "One line of text
followed by another line
and another line"
are exported in the following format:
propertyName: >
One line of text
followed by another line
and another line
Note the extra (unwanted) line breaks.
According to this YAML Multiline guide, the format used here is the folded block scalar style. Is there a way using YamlDotNet to change the style of this output for all multi-line string properties to literal block scalar style or one of the flow scalar styles?
The YamlDotNet documentation shows how to apply ScalarStyle.DoubleQuoted to a particular property using WithAttributeOverride but this requires a class name and the model to be serialised is dynamic. This also requires listing every property to change (of which there are many). I would like to change the style for all multi-line string properties at once.
To answer my own question, I've now worked out how to do this by deriving from the ChainedEventEmitter class and overriding void Emit(ScalarEventInfo eventInfo, IEmitter emitter). See code sample below.
public class MultilineScalarFlowStyleEmitter : ChainedEventEmitter
{
public MultilineScalarFlowStyleEmitter(IEventEmitter nextEmitter)
: base(nextEmitter) { }
public override void Emit(ScalarEventInfo eventInfo, IEmitter emitter)
{
if (typeof(string).IsAssignableFrom(eventInfo.Source.Type))
{
string value = eventInfo.Source.Value as string;
if (!string.IsNullOrEmpty(value))
{
bool isMultiLine = value.IndexOfAny(new char[] { '\r', '\n', '\x85', '\x2028', '\x2029' }) >= 0;
if (isMultiLine)
eventInfo = new ScalarEventInfo(eventInfo.Source)
{
Style = ScalarStyle.Literal
};
}
}
nextEmitter.Emit(eventInfo, emitter);
}
}
I want to implement Enum for Number, I want to get its respective String values. I already followed link: http://www.makeinjava.com/convert-enum-integer-string-value-java/.
The error which I'm getting is
Syntax error on token "1", Identifier expected
Syntax error on token "2", Identifier expected
public enum CompanyCityType {
1("New York"),
2("Reston");
private Integer companyCityType;
CompanyCityType(Integer companyCityType) {
this.companyCityType = companyCityType;
}
public Integer getCompanyAddrType() {
return this.companyCityType;
}
}
You cannot begin any identifier name in Java with a number, it must follow the rules as specified for having a valid variable name in Java.
As per the Oracle variable tutorial:
Variable names are case-sensitive. A variable's name can be any legal
identifier — an unlimited-length sequence of Unicode letters and
digits, beginning with a letter, the dollar sign "$", or the
underscore character "_".
As the fields in an enum are actually public static final fields (singleton instances) or class variables they follow the same set of naming rules as a normal Java variable.
You need to refactor your code to:
public enum CompanyCityType {
NEW_YORK(1),
RESTON(2);
private int companyCityType;
CompanyCityType(int companyCityType) {
this.companyCityType = companyCityType;
}
public int getCompanyAddrType() {
return this.companyCityType;
}
}
I'm experimenting with Stanford NLP's TokensRegex and try to find dimensions (e.g. 100x120) in a text. So my plan is to first retokenize the input to further split these tokens (using the example provided in retokenize.rules.txt) and then to search for the new pattern.
After doing the retokenization, however, only null-values are left that replace the original string:
The top level annotation
[Text=100x120 Tokens=[null-1, null-2, null-3] Sentences=[100x120]]
The retokenization seems to work fine (3 tokens in result), but the values are lost. What can I do to maintain the original values in the tokens list?
My retokenize.rules.txt file is (as in the demo):
tokens = { type: "CLASS", value:"edu.stanford.nlp.ling.CoreAnnotations$TokensAnnotation" }
options.matchedExpressionsAnnotationKey = tokens;
options.extractWithTokens = TRUE;
options.flatten = TRUE;
ENV.defaults["ruleType"] = "tokens"
ENV.defaultStringPatternFlags = 2
ENV.defaultResultAnnotationKey = tokens
{ pattern: ( /\d+(x|X)\d+/ ), result: Split($0[0], /x|X/, TRUE) }
The main method:
public static void main(String[] args) throws IOException {
//...
text = "100x120";
Properties properties = new Properties();
properties.setProperty("tokenize.language", "de");
properties.setProperty("annotators", tokenize,retokenize,ssplit,pos,lemma,ner");
properties.setProperty("customAnnotatorClass.retokenize", "edu.stanford.nlp.pipeline.TokensRegexAnnotator");
properties.setProperty("retokenize.rules", "retokenize.rules.txt");
StanfordCoreNLP stanfordPipeline = new StanfordCoreNLP(properties);
runPipeline(pipelineWithRetokenize, text);
}
And the pipeline:
public static void runPipeline(StanfordCoreNLP pipeline, String text) {
Annotation annotation = new Annotation(text);
pipeline.annotate(annotation);
out.println();
out.println("The top level annotation");
out.println(annotation.toShorterString());
//...
}
Thanks for letting us know. The CoreAnnotations.ValueAnnotation is not being populated and we'll update TokenRegex to populate the field.
Regardless, you should be able to use TokenRegex to retokenize as you have planned. Most of the pipeline does not depending on the ValueAnnotation and uses the CoreAnnotations.TextAnnotation instead. You can use the CoreAnnotations.TextAnnotation to get the text for the new tokens (each token is a CoreLabel so you can access it using token.word() as well).
See TokensRegexRetokenizeDemo for example code on how to get the different annotations out.
getSimpleJdbcTemplate().query(sql, getMapper()); returns List, but I need a Map where key will be store data of one of the field of object. For example, I have object named "Currency" which has fields: id, code, name, etc. Code above will return List object, but I want to get currency by id from Map. Now, I wrote the following code:
#Override
public Map<Integer, Currency> listCurrencies() {
String sql = "select cur_id, cur_code, cur_name ... from currencies";
List<Currency> currencies = getSimpleJdbcTemplate().query(sql, getMapper());
Map<Integer, Currency> map = new HashMap<Integer, Currency>(currencies.size());
for (Currency currency : currencies) {
map.put(currency.getId(), currency);
}
return map;
}
Are there any way to do same but without creating List object and looping inside it?
You have ResultSetExtractor for extracting values from the ResultSet. So in your case you can write a custom ResultSetExtractor which will return you the Map object.
According to the MSDN documentation, XMLWriter.WriteValue writes xsd type information to the xml for simple CLR types. Then XMLReader.ReadContentAsObject supposedly reads out the appropriately-typed object when the XML is parsed. However, this always seems to return a string object for me and the ValueType property of the XMLReader is string. I've tried inserting longs and DateTimes, but they always end up as strings. Any ideas what I'm doing wrong or is this a Windows Phone bug?
XML Writing Code
public void WriteXml(XmlWriter writer) {
// KeyValuePair<string, object> pair initialized previously
writer.WriteStartElement(pair.Key);
writer.WriteValue(pair.Value)
writer.WriteEndElement();
}
XML Parsing Code
public void ReadXml(XMLReader reader) {
while (reader.Read()) {
if (reader.NodeType == XmlNodeType.Element) {
Type T = reader.ValueType; // T is string
reader.ReadStartElement();
object o = reader.ReadContentAsObject(); // o is string
o = reader.ReadContentAs(T, null); // o is string
}
}
}
You need to use a schema file (XSD) so that the framework can infer the type of a node. Otherwise ValueType will always return System.String.
MSDN says:
If a validation error occurs while parsing the content and the reader is an XmlReader object created by the Create method, the reader returns the content as a string. In other words when a validation error or warning occurs, the content is considered to be untyped.
I was making this too difficult. My goal was to serialize a Dictionary with generic type (string, object) by traversing its KeyValuePairs , but that class doesn't seem to be serializeable using XmlSerializer. I just created another class with two public properties, Key and Value, so I could use XmlSerializer. When deserializing with XmlSerializer, the type of Value is restored as long as it is a supported CLR type.
public void WriteXml(XmlWriter writer) {
// KeyValuePair<string, object> pair initialized previously
writer.WriteStartElement("entry");
MyClass toSerialize = new MyClass(pair.Key, pair.Value);
XmlSerializer serializer = new XmlSerializer(typeof(MyClass));
serializer.Serialize(writer, toSerialize);
writer.WriteEndElement();
}