How can I used named parameters in a messages.properties file? - java

Is there any way to have message.properties records as follows
message.myMessage=This message is for ${name} in ${location}
as opposed to
message.myMessage = This message is for {0} in {1}
When I am creating the messages, I don't neccessarily know the order / how many parameters are needed, but I am able just pass in several properties by name, and just the correct ones would be used.

After facing the very same question and poking in source code I found a "loop-hole" that makes it possible in a very easy way:
message.myMessage = This message is for {0,,name} in {1,,location}
This approach doesn't eliminate usage of numbers. The reason to use it is to give hints to translation folks.

I am afraid not, parameters are an Object array so there is no way to define names for them. If you always passes in the array of parameter in the same order though you could use them like this:
message.myMessage = This message is for {0} in {1}
message.myNameMessage = This message is for {0}
message.myLocationMessage = This message is for people in {1}
message.myAlternateMessage = The message params are location: {1}; name: {0}

Take a look at ICU4J
It allows for something like this:
message.myMessage=This message is for {name} in {location}.
And it is way more powerful than the simple replacements suggested, because can do locale aware formatting of the parameters (ie: "Subscription expires on: {expirationDate, date, long})
http://icu-project.org/apiref/icu4j/com/ibm/icu/text/MessageFormat.html

Unfortunately the MessageFormat API does not support named parameters, only argument-index:
Patterns and Their Interpretation
MessageFormat uses patterns of the following form:
MessageFormatPattern:
String
MessageFormatPattern FormatElement String
FormatElement:
{ ArgumentIndex }
{ ArgumentIndex , FormatType }
{ ArgumentIndex , FormatType , FormatStyle }

Everything is possible for those who try... I never heard about something like that for Java, but you can write it by yourself.
Please take a look at this example:
public String format(String message, String... arguments) {
for (String argument : arguments) {
String[] keyValue = argument.split("=");
if (keyValue.length != 2)
throw new IllegalArgumentException("Incorrect argument: " + argument);
String placeholder = "${" + keyValue[0] + "}";
if (!message.contains(placeholder))
throw new IllegalArgumentException(keyValue[0] + " does not exists.");
while (message.contains(placeholder))
message = message.replace(placeholder, keyValue[1]);
}
return message;
}
It is not ideal, as you actually would call it with hardcoded string (which is generally bad idea) and you would be forced to use Strings only, but it can be done. The only question is if it is practical.

It is possible using apache commons lang library.
https://commons.apache.org/proper/commons-lang/
Properties messages = ...
Map<String, String> m = new HashMap<>();
m.put("name", "Mithu");
m.put("location", "Dhaka");
StrSubstitutor sub = new StrSubstitutor(m);
String msg = sub.replace(messages.getProperty("message.myMessage"));
// msg = This message is for Mithu in Dhaka

Related

Java: how to format string with logging-like pattern?

Sometimes it's required to compose a string using logging-like pattern:
Something went wrong, detailA={}, detailB={}
but not in order to log it, but for other purposes (e.g. send over network).
Sometimes it's causing code duplication, like this:
logger.info("Something went wrong, detailA={}, detailB={}", detailA, detailB));
otherSystem.info(String.format("Something went wrong, detailA=%s, detailB=%s",
detailA, detailB);
Which is highly inconvenient and error-prone. How to format a string using logging pattern and logging-like API?
If you using slf4j, you can use its MessageFormatter.arrayFormat which returns a FormattingTuple,
FormattingTuple ft = MessageFormatter.arrayFormat(format, argArray);
And then convert it to a string.
String msg = ft.getMessage();
Which means you can add a utility method for that
static String format(String format,String...params){
FormattingTuple ft = MessageFormatter.arrayFormat(format,params);
String message = ft.getMessage();
return message;
}
System.out.println(format("hi {}, you {}","there","rock"));

Using a resource loader for FileWritingMessageHandler

When using a directory-expression for an <int-file:outbound-gateway> endpoint, the method below is called on org.springframework.integration.file.FileWritingMessageHandler:
private File evaluateDestinationDirectoryExpression(Message<?> message) {
final File destinationDirectory;
final Object destinationDirectoryToUse = this.destinationDirectoryExpression.getValue(
this.evaluationContext, message);
if (destinationDirectoryToUse == null) {
throw new IllegalStateException(String.format("The provided " +
"destinationDirectoryExpression (%s) must not resolve to null.",
this.destinationDirectoryExpression.getExpressionString()));
}
else if (destinationDirectoryToUse instanceof String) {
final String destinationDirectoryPath = (String) destinationDirectoryToUse;
Assert.hasText(destinationDirectoryPath, String.format(
"Unable to resolve destination directory name for the provided Expression '%s'.",
this.destinationDirectoryExpression.getExpressionString()));
destinationDirectory = new File(destinationDirectoryPath);
}
else if (destinationDirectoryToUse instanceof File) {
destinationDirectory = (File) destinationDirectoryToUse;
} else {
throw new IllegalStateException(String.format("The provided " +
"destinationDirectoryExpression (%s) must be of type " +
"java.io.File or be a String.", this.destinationDirectoryExpression.getExpressionString()));
}
validateDestinationDirectory(destinationDirectory, this.autoCreateDirectory);
return destinationDirectory;
}
Based on this code I see that if the directory to use evaluates to a String, it uses that String to create a new java.io.File object.
Is there a reason that a ResourceLoader couldn't/shouldn't be used instead of directly creating a new file?
I ask because my expression was evaluating to a String of the form 'file://path/to/file/' which of course is an invalid path for the java.io.File(String) constructor. I had assumed that Spring would treat the String the same way as it treats the directory attribute on <int-file:outbound-gateway> and pass it through a ResourceLoader.
Excerpt from my configuration file:
<int-file:outbound-gateway
request-channel="inputChannel"
reply-channel="updateTable"
directory-expression="
'${baseDirectory}'
+
T(java.text.MessageFormat).format('${dynamicPathPattern}', headers['Id'])
"
filename-generator-expression="headers.filename"
delete-source-files="true"/>
Where baseDirectory is a property that changes per-environment of the form 'file://hostname/some/path/'
There's no particular reason that this is the case, it probably just wasn't considered at the time of implementation.
The request sounds reasonable to me and will benefit others (even though you have found a work-around), by providing simpler syntax. Please open an 'Improvement' JIRA issue; thanks.
While not directly answering the question, I wanted to post the workaround that I used.
In my XML configuration, I changed the directory-expression to evaluate to a file through the DefaultResourceLoader instead of a String.
So this is what my new configuration looked like:
<int-file:outbound-gateway
request-channel="inputChannel"
reply-channel="updateTable"
directory-expression=" new org.springframework.core.io.DefaultResourceLoader().getResource(
'${baseDirectory}'
+
T(java.text.MessageFormat).format('${dynamicPathPattern}', headers['Id'])).getFile()
"
filename-generator-expression="headers.filename"
delete-source-files="true"/>

Find an String with some keys in java

Consider a map as below:
Map("PDF","application/pdf")
Map("XLSX","application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")
Map("CVS","application/csv")
....
There is an export method which gets the export button name and find the export type and application content type
public void setExport(String exportBtn) {
for (String key : exportTypes.keySet()) {
if (exportBtn.contains(key)) {
this.export = key;
this.exportContentType = exportTypes.get(key);
LOG.debug("Exporting to {} ", this.export);
return ;
}
}
}
This method can be called as
setExport("PDF") >> export=PDF, exportContentType=application/pdf
setExport("Make and PDF") >> PDF, exportContentType=application/pdf
setExport("PDF Maker") >> PDF, exportContentType=application/pdf
I am not feeling good with this approch! At least I think there is some libs, for example in StringUtils, which can do something like:
String keys[]={"PDF","XLSX","CVS"};
String input="Make the PDF";
selectedKey = StringUtils.xxx(input,keys);
This can some how simplify my method.
But I could not find anything. Any comments?!
You could use Regex to solve this issue, something like this:
final Pattern pattern = Pattern.compile("(PDF|XLSX|CVS)");
final Matcher matcher = pattern.matcher("Make the PDF");
if (matcher.find()) {
setExportType(matcher.group());
}
You then need to create the pattern procedurally to include all keys once, and of course use the button's name instead of "Make the PDF".
Map is the easy and best implementation to store key-value pairs.
Why cannot you directly use the get method of map with key?
exportContentType = exportTypes.get(exportBtn);
if(exportContentType !=null || exportcontentType.isEmpty())
throw error;
else
export = exportBtn;

How to convert a String FIX message to FIX FIX50SP2 format using QuickFixJ

Need a quick help. I am a newbie in QuickFixJ. I have a FIX message in a txt file. I need to convert that into FIX50SP2 format. I am enclosing the code snippet.
String fixMsg = "1128=99=25535=X49=CME34=47134052=20100318-03:21:11.36475=20120904268=2279=122=848=336683=607400107=ESU2269=1270=140575271=152273=121014000336=2346=521023=1279=122=848=336683=607401107=ESU2269=1270=140600271=206273=121014000336=2346=681023=210=159";
System.out.println("FixMsg String:"+fixMsg);
Message FIXMessage = new Message();
DataDictionary dd = new DataDictionary("FIX50SP2.xml");
FIXMessage.fromString(fixMsg, dd, false);
System.out.println("FIXMessage Output:" + FIXMessage.toString()); // Print message after parsing
MsgType msgType = new MsgType();
System.out.println(FIXMessage.getField(msgType));
Here is the output:
FixMsg String:1128=99=15835=X49=CME34=47164052=2012090312102051175=20120904268=1279=122=848=336683=607745107=ESU2269=1270=140575271=123273=121020000336=2346=501023=110=205
FIXMessage Output:9=6135=X34=47164049=CME52=2012090312102051175=20120904268=110=117
quickfix.FieldNotFound: Field [35] was not found in message.
at quickfix.FieldMap.getField(FieldMap.java:216)
at quickfix.FieldMap.getFieldInternal(FieldMap.java:353)
at quickfix.FieldMap.getField(FieldMap.java:349)
at MainApp.main(MainApp.java:52)
I want to extract MsgType field (field 35). Could you please tell me where I am wrong? The thing I have observed is that after parsing to FIX50SP2 format, the convert FIX message is missing many data element (for details see the output)
Thanks
Like others mentioned the MsgType is an header field and you get it by using the following
String msgType = null;
if(FIXMessage.getHeader().isSetField(MsgType.FIELD)) {
msgType = FIXMessage.getHeader().getString(MsgType.FIELD);
}
System.out.println("MsgType is " + msgType);`
The reason you are missing many data element after parsing is, probably your message have some custom tags(like tag 2346), which is not defined in your data dictionary(FIXSP02.xml). hence the parsing of those tags failed and missing in the output.
To fix this, get the data dictionary from the party that is sending you the message and use it to parse the message
I'm not familiar with FIX messages and QuickFixJ, but glancing at the Javadoc, it seems like you should use the identifyType method :
String fixMsg = "1128=99=25535=X49=CME34=47134052=20100318-03:21:11.36475=20120904268=2279=122=848=336683=607400107=ESU2269=1270=140575271=152273=121014000336=2346=521023=1279=122=848=336683=607401107=ESU2269=1270=140600271=206273=121014000336=2346=681023=210=159";
MsgType msgType = Message.identifyType(fixMsg);
You may find FixB framework useful as it deals well with non-standard use cases of FIX.
As in your case, to extract only data you are interested in, you need to define a class that will represent this data and to bind it to FIX using annotations. E.g.:
#FixBlock
public class MDEntry {
#FixField(tag=269) public int entryType; // you could define an enum type for it as well
#FixField(tag=278) public String entryId;
#FixField(tag=55) public String symbol;
}
...
FixFieldExtractor fixExtractor = new NativeFixFieldExtractor();
List<MDEntry> mdEntries = fixExtractor.getGroups(fixMsg, List.class, 268, FixMetaScanner.scanClass(MDEntry.class))
In more common cases, FixSerializer interface should be used, but it requires a message with MsgType(35) tag and a class annotated with #FixMessage(type="...") accordingly. E.g.:
#FixMessage(type="X")
public class MarketData {
#FixGroup(tag=268) public List<MDEntry> entries;
}
...
FixMetaDictionary fixMetaDictionary = FixMetaScanner.scanClassesIn("my.fix.classes.package");
FixSerializer fixSerializer = new NativeFixSerializer("FIX.5.0.SP2", fixMetaDictionary);
MarketData marketData = fixSerializer.deserialize(fixMsg);
I hope you will find it useful.
If you need just a MsgTyp, you're sure the message is correct and you do not need any other field from the message, then I would recommend extracting MsgType from string using regexp.
e.g.: \u000135=(\w+)\u0001
It is MUCH FASTER than parsing (and validating) a string via QuickFix.

Get request parameter with Play Framework?

I am learning play framework and understand that I can map a request such as /manager/user as:
GET /manage/:user Controllers.Application.some(user:String)
How would I map a request like /play/video?video_id=1sh1?
You have at least two possibilities, let's call them approach1 and approach2.
In the first approach you can declare a routes param with some default value. 0 is good candidate, as it will be easiest to build some condition on top of it. Also it's typesafe, and pre-validates itself. I would recommend this solution at the beginning.
Second approach reads params directly from request as a String so you need to parse it to integer and additionally validate if required.
routes:
GET /approach1 controllers.Application.approach1(video_id: Int ?=0)
GET /approach2 controllers.Application.approach2
actions:
public static Result approach1(int video_id) {
if (video_id == 0) return badRequest("Wrong video ID");
return ok("1: Display video no. " + video_id);
}
public static Result approach2() {
int video_id = 0;
if (form().bindFromRequest().get("video_id") != null) {
try {
video_id = Integer.parseInt(form().bindFromRequest().get("video_id"));
} catch (Exception e) {
Logger.error("int not parsed...");
}
}
if (video_id == 0) return badRequest("Wrong video ID");
return ok("2: Display video no. " + video_id);
}
PS: LOL I just realized that you want to use String identifier... anyway both approaches will be similar :)
I would do it simply using:
GET /play/video Controllers.Application.video(video_id:String)
And at controller you would of course have, something like:
public static Result video(String video_id) {
return ok("We got video id of: " + video_id);
}
Alternatively, you dont have to add video_id:String since play seems to treat parameters as String by default, so it also works like this (at least with newest play):
GET /play/video Controllers.Application.video(video_id)
Typing localhost:9000/play/video?video_id=1sh1 to address bar should now you give view which prints:
We got video id of: 1sh1
To add more parameters is simple, like this:
GET /play/video controllers.Application.video(video_id:String, site:String, page:Integer)
Controller:
public static Result video(String video_id, String site, Integer page) {
return ok("We got video id of: " + video_id + " site: " + site + " page: " + page);
}
Typing localhost:9000/play/video?video_id=1as1&site=www.google.com&page=3 to address bar should now you give view which prints:
We got video id of: 1as1 site: www.google.com page: 3
You're welcome ^^.
I'm not quite sure if I got what you meant if you meant just to map a url to function in controller the answer of biesior is perfect but if you mean submitting a form with get method like
#helper.form(action = routes.YourController.page1()) {
}
and having the form's parameter in the url in the url-rewrited format like
page1/foo/bar instead of page1?param1=foo&param2=bar
There is no way to do that because that's http specs
I do often circumvent this limitation by getting the parameters in the first function in controller and then redirect them to another view just like the following
public static Result page1(){
String param1 = Form.form().bindFromRequest().get("param1");
String param2= Form.form().bindFromRequest().get("param2");
return ( redirect( routes.YourController.page2(param1,param2)));
}
Then have whatever in the page2
public static Result page2(String param1,String param2){
...............
}
And have this in the routes file :
GET page2/:param1/:param2 controllers.YourControllers.page2(param1 : String, param2 : String )
I hope it'd help but I'm not sure that's the best practise
Ok so I just read up the documentation and what I understand is that you need to
GET /play/video Controllers.Application.video()
And then in the controller call the getQueryString of the HttpRequest object
http://www.playframework.com/documentation/api/2.1.0/java/index.html

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