This might be a duplicate. But I cannot find a solution to my Problem.
I have a class
public class MyResponse implements Serializable {
private boolean isSuccess;
public boolean isSuccess() {
return isSuccess;
}
public void setSuccess(boolean isSuccess) {
this.isSuccess = isSuccess;
}
}
Getters and setters are generated by Eclipse.
In another class, I set the value to true, and write it as a JSON string.
System.out.println(new ObjectMapper().writeValueAsString(myResponse));
In JSON, the key is coming as {"success": true}.
I want the key as isSuccess itself. Is Jackson using the setter method while serializing? How do I make the key the field name itself?
This is a slightly late answer, but may be useful for anyone else coming to this page.
A simple solution to changing the name that Jackson will use for when serializing to JSON is to use the #JsonProperty annotation, so your example would become:
public class MyResponse implements Serializable {
private boolean isSuccess;
#JsonProperty(value="isSuccess")
public boolean isSuccess() {
return isSuccess;
}
public void setSuccess(boolean isSuccess) {
this.isSuccess = isSuccess;
}
}
This would then be serialised to JSON as {"isSuccess":true}, but has the advantage of not having to modify your getter method name.
Note that in this case you could also write the annotation as #JsonProperty("isSuccess") as it only has the single value element
I recently ran into this issue and this is what I found. Jackson will inspect any class that you pass to it for getters and setters, and use those methods for serialization and deserialization. What follows "get", "is" and "set" in those methods will be used as the key for the JSON field ("isValid" for getIsValid and setIsValid).
public class JacksonExample {
private boolean isValid = false;
public boolean getIsValid() {
return isValid;
}
public void setIsValid(boolean isValid) {
this.isValid = isValid;
}
}
Similarly "isSuccess" will become "success", unless renamed to "isIsSuccess" or "getIsSuccess"
Read more here: http://www.citrine.io/blog/2015/5/20/jackson-json-processor
Using both annotations below, forces the output JSON to include is_xxx:
#get:JsonProperty("is_something")
#param:JsonProperty("is_something")
When you are using Kotlin and data classes:
data class Dto(
#get:JsonProperty("isSuccess") val isSuccess: Boolean
)
You might need to add #param:JsonProperty("isSuccess") if you are going to deserialize JSON as well.
EDIT: If you are using swagger-annotations to generate documentation, the property will be marked as readOnly when using #get:JsonProperty. In order to solve this, you can do:
#JsonAutoDetect(isGetterVisibility = JsonAutoDetect.Visibility.NONE)
data class Dto(
#field:JsonProperty(value = "isSuccess") val isSuccess: Boolean
)
You can configure your ObjectMapper as follows:
mapper.setPropertyNamingStrategy(new PropertyNamingStrategy() {
#Override
public String nameForGetterMethod(MapperConfig<?> config, AnnotatedMethod method, String defaultName)
{
if(method.hasReturnType() && (method.getRawReturnType() == Boolean.class || method.getRawReturnType() == boolean.class)
&& method.getName().startsWith("is")) {
return method.getName();
}
return super.nameForGetterMethod(config, method, defaultName);
}
});
I didn't want to mess with some custom naming strategies, nor re-creating some accessors.
The less code, the happier I am.
This did the trick for us :
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonProperty;
#JsonIgnoreProperties({"success", "deleted"}) // <- Prevents serialization duplicates
public class MyResponse {
private String id;
private #JsonProperty("isSuccess") boolean isSuccess; // <- Forces field name
private #JsonProperty("isDeleted") boolean isDeleted;
}
Building upon Utkarsh's answer..
Getter names minus get/is is used as the JSON name.
public class Example{
private String radcliffe;
public getHarryPotter(){
return radcliffe;
}
}
is stored as { "harryPotter" : "whateverYouGaveHere" }
For Deserialization, Jackson checks against both the setter and the field name.
For the Json String { "word1" : "example" }, both the below are valid.
public class Example{
private String word1;
public setword2( String pqr){
this.word1 = pqr;
}
}
public class Example2{
private String word2;
public setWord1(String pqr){
this.word2 = pqr ;
}
}
A more interesting question is which order Jackson considers for deserialization. If i try to deserialize { "word1" : "myName" } with
public class Example3{
private String word1;
private String word2;
public setWord1( String parameter){
this.word2 = parameter ;
}
}
I did not test the above case, but it would be interesting to see the values of word1 & word2 ...
Note: I used drastically different names to emphasize which fields are required to be same.
You can change primitive boolean to java.lang.Boolean (+ use #JsonPropery)
#JsonProperty("isA")
private Boolean isA = false;
public Boolean getA() {
return this.isA;
}
public void setA(Boolean a) {
this.isA = a;
}
Worked excellent for me.
If you are interested in handling 3rd party classes not under your control (like #edmundpie mentioned in a comment) then you add Mixin classes to your ObjectMapper where the property/field names should match the ones from your 3rd party class:
public class MyStack32270422 {
public static void main(String[] args) {
ObjectMapper om3rdParty = new ObjectMapper();
om3rdParty .addMixIn(My3rdPartyResponse.class, MixinMyResponse.class);
// add further mixins if required
String jsonString = om3rdParty.writeValueAsString(new My3rdPartyResponse());
System.out.println(jsonString);
}
}
class MixinMyResponse {
// add all jackson annotations here you want to be used when handling My3rdPartyResponse classes
#JsonProperty("isSuccess")
private boolean isSuccess;
}
class My3rdPartyResponse{
private boolean isSuccess = true;
// getter and setter here if desired
}
Basically you add all your Jackson annotations to your Mixin classes as if you would own the class. In my opinion quite a nice solution as you don't have to mess around with checking method names starting with "is.." and so on.
there is another method for this problem.
just define a new sub-class extends PropertyNamingStrategy and pass it to ObjectMapper instance.
here is a code snippet may be help more:
mapper.setPropertyNamingStrategy(new PropertyNamingStrategy() {
#Override
public String nameForGetterMethod(MapperConfig<?> config, AnnotatedMethod method, String defaultName) {
String input = defaultName;
if(method.getName().startsWith("is")){
input = method.getName();
}
//copy from LowerCaseWithUnderscoresStrategy
if (input == null) return input; // garbage in, garbage out
int length = input.length();
StringBuilder result = new StringBuilder(length * 2);
int resultLength = 0;
boolean wasPrevTranslated = false;
for (int i = 0; i < length; i++)
{
char c = input.charAt(i);
if (i > 0 || c != '_') // skip first starting underscore
{
if (Character.isUpperCase(c))
{
if (!wasPrevTranslated && resultLength > 0 && result.charAt(resultLength - 1) != '_')
{
result.append('_');
resultLength++;
}
c = Character.toLowerCase(c);
wasPrevTranslated = true;
}
else
{
wasPrevTranslated = false;
}
result.append(c);
resultLength++;
}
}
return resultLength > 0 ? result.toString() : input;
}
});
The accepted answer won't work for my case.
In my case, the class is not owned by me. The problematic class comes from 3rd party dependencies, so I can't just add #JsonProperty annotation in it.
To solve it, inspired by #burak answer above, I created a custom PropertyNamingStrategy as follow:
mapper.setPropertyNamingStrategy(new PropertyNamingStrategy() {
#Override
public String nameForSetterMethod(MapperConfig<?> config, AnnotatedMethod method, String defaultName)
{
if (method.getParameterCount() == 1 &&
(method.getRawParameterType(0) == Boolean.class || method.getRawParameterType(0) == boolean.class) &&
method.getName().startsWith("set")) {
Class<?> containingClass = method.getDeclaringClass();
String potentialFieldName = "is" + method.getName().substring(3);
try {
containingClass.getDeclaredField(potentialFieldName);
return potentialFieldName;
} catch (NoSuchFieldException e) {
// do nothing and fall through
}
}
return super.nameForSetterMethod(config, method, defaultName);
}
#Override
public String nameForGetterMethod(MapperConfig<?> config, AnnotatedMethod method, String defaultName)
{
if(method.hasReturnType() && (method.getRawReturnType() == Boolean.class || method.getRawReturnType() == boolean.class)
&& method.getName().startsWith("is")) {
Class<?> containingClass = method.getDeclaringClass();
String potentialFieldName = method.getName();
try {
containingClass.getDeclaredField(potentialFieldName);
return potentialFieldName;
} catch (NoSuchFieldException e) {
// do nothing and fall through
}
}
return super.nameForGetterMethod(config, method, defaultName);
}
});
Basically what this does is, before serializing and deserializing, it checks in the target/source class which property name is present in the class, whether it is isEnabled or enabled property.
Based on that, the mapper will serialize and deserialize to the property name that is exist.
public bool IsList(object value)
{
Type type = value.GetType();
// Check if type is a generic list of any type
}
What's the best way to check if the given object is a list, or can be cast to a list?
For you guys that enjoy the use of extension methods:
public static bool IsGenericList(this object o)
{
var oType = o.GetType();
return (oType.IsGenericType && (oType.GetGenericTypeDefinition() == typeof(List<>)));
}
So, we could do:
if(o.IsGenericList())
{
//...
}
using System.Collections;
if(value is IList && value.GetType().IsGenericType) {
}
bool isList = o.GetType().IsGenericType
&& o.GetType().GetGenericTypeDefinition() == typeof(IList<>));
public bool IsList(object value) {
return value is IList
|| IsGenericList(value);
}
public bool IsGenericList(object value) {
var type = value.GetType();
return type.IsGenericType
&& typeof(List<>) == type.GetGenericTypeDefinition();
}
Here's an implementation that works in .NET Standard, and works against interfaces:
public static bool ImplementsGenericInterface(this Type type, Type interfaceType)
{
return type
.GetTypeInfo()
.ImplementedInterfaces
.Any(x => x.GetTypeInfo().IsGenericType && x.GetGenericTypeDefinition() == interfaceType);
}
And here are the tests (xunit):
[Fact]
public void ImplementsGenericInterface_List_IsValidInterfaceTypes()
{
var list = new List<string>();
Assert.True(list.GetType().ImplementsGenericInterface(typeof(IList<>)));
Assert.True(list.GetType().ImplementsGenericInterface(typeof(IEnumerable<>)));
Assert.True(list.GetType().ImplementsGenericInterface(typeof(IReadOnlyList<>)));
}
[Fact]
public void ImplementsGenericInterface_List_IsNotInvalidInterfaceTypes()
{
var list = new List<string>();
Assert.False(list.GetType().ImplementsGenericInterface(typeof(string)));
Assert.False(list.GetType().ImplementsGenericInterface(typeof(IDictionary<,>)));
Assert.False(list.GetType().ImplementsGenericInterface(typeof(IComparable<>)));
Assert.False(list.GetType().ImplementsGenericInterface(typeof(DateTime)));
}
if(value is IList && value.GetType().GetGenericArguments().Length > 0)
{
}
Based on Victor Rodrigues' answer, we can devise another method for generics. In fact, the original solution can be reduced to only two lines:
public static bool IsGenericList(this object Value)
{
var t = Value.GetType();
return t.IsGenericType && t.GetGenericTypeDefinition() == typeof(List<>);
}
public static bool IsGenericList<T>(this object Value)
{
var t = Value.GetType();
return t.IsGenericType && t.GetGenericTypeDefinition() == typeof(List<T>);
}
I'm using the following code:
public bool IsList(Type type) => type.IsGenericType && (
(type.GetGenericTypeDefinition() == typeof(List<>))
|| (type.GetGenericTypeDefinition() == typeof(IList<>))
);
Probably the best way would be to do something like this:
IList list = value as IList;
if (list != null)
{
// use list in here
}
This will give you maximum flexibility and also allow you to work with many different types that implement the IList interface.
First let me apologize a bit for the length of this post, it's mostly code though so I hope you all bear with me!
I have a scenario in dealing with a legacy database, where I needed to write an IUserType using NHibernate 3.2 to take a 2 character "status" field and return a Boolean value from it. The status field can hold 3 possible values:
* 'DI' // 'Disabled', return false
* ' ' // blank or NULL, return true
* NULL
Here is what I have simplified.
Table Definition:
CREATE TABLE [dbo].[Client](
[clnID] [int] IDENTITY(1,1) NOT NULL,
[clnStatus] [char](2) NULL,
[clnComment] [varchar](250) NULL,
[clnDescription] [varchar](150) NULL,
[Version] [int] NOT NULL
)
Fluent Mapping:
public class ClientMapping : CoreEntityMapping<Client>
{
public ClientMapping()
{
SchemaAction.All().Table("Client");
LazyLoad();
Id(x => x.Id, "clnId").GeneratedBy.Identity();
Version(x => x.Version).Column("Version").Generated.Never().UnsavedValue("0").Not.Nullable();
OptimisticLock.Version();
Map(x => x.Comment, "clnComment").Length(250).Nullable();
Map(x => x.Description, "clnDescription").Length(250).Nullable();
Map(x => x.IsActive, "clnStatus").Nullable().CustomType<StatusToBoolType>();
}
}
My IUserType Implementation:
public class StatusToBoolType : IUserType
{
public bool IsMutable { get { return false; } }
public Type ReturnedType { get { return typeof(bool); } }
public SqlType[] SqlTypes { get { return new[] { NHibernateUtil.String.SqlType }; } }
public object DeepCopy(object value)
{
return value;
}
public object Replace(object original, object target, object owner)
{
return original;
}
public object Assemble(object cached, object owner)
{
return cached;
}
public object Disassemble(object value)
{
return value;
}
public new bool Equals(object x, object y)
{
if (ReferenceEquals(x, y)) return true;
if (x == null || y == null) return false;
return x.Equals(y);
}
public int GetHashCode(object x)
{
return x == null ? typeof(bool).GetHashCode() + 473 : x.GetHashCode();
}
public object NullSafeGet(IDataReader rs, string[] names, object owner)
{
var obj = NHibernateUtil.String.NullSafeGet(rs, names[0]);
if (obj == null) return true;
var status = (string)obj;
if (status == " ") return true;
if (status == "DI") return false;
throw new Exception(string.Format("Expected data to be either empty or 'DI' but was '{0}'.", status));
}
public void NullSafeSet(IDbCommand cmd, object value, int index)
{
var parameter = ((IDataParameter) cmd.Parameters[index]);
var active = value == null || (bool) value;
if (active)
parameter.Value = " ";
else
parameter.Value = "DI";
}
}
However this doesn't work. This unit test fails with an inaccurate count.
[TestMethod]
public void GetAllActiveClientsTest()
{
//ACT
var count = Session.QueryOver<Client>()
.Where(x => x.IsActive)
.SelectList(l => l.SelectCount(x => x.Id))
.FutureValue<int>().Value;
//ASSERT
Assert.AreNotEqual(0, count);
Assert.AreEqual(1721, count);
}
The reason it fails is because it generates the following SQL:
SELECT count(this_.clnID) as y0_ FROM Client this_ WHERE this_.clnstatus = #p0;
/* #p0 = ' ' [Type: String (0)] */
But I need it to generate this instead:
SELECT count(this_.clnID) as y0_ FROM Client this_ WHERE (this_.clnstatus = #p0 <b> OR this_.clnstatus IS NULL);</b>
After some debugging I saw that the NullSafeSet() method in my StatusToBoolType class is invoked before the query is generated, so I was able to get around this by writing some hackish code in that method to manipulate the SQL in the cmd.CommandText property.
...
public void NullSafeSet(IDbCommand cmd, object value, int index)
{
var parameter = ((IDataParameter) cmd.Parameters[index]);
var active = value == null || (bool) value;
if (active)
{
parameter.Value = " ";
if (cmd.CommandText.ToUpper().StartsWith("SELECT") == false) return;
var paramindex = cmd.CommandText.IndexOf(parameter.ParameterName);
if (paramindex > 0)
{
// Purpose: change [columnName] = #p0 ==> ([columnName] = #p0 OR [columnName] IS NULL)
paramindex += parameter.ParameterName.Length;
var before = cmd.CommandText.Substring(0, paramindex);
var after = cmd.CommandText.Substring(paramindex);
//look at the text before the '= #p0' and find the column name...
var columnSection = before.Split(new[] {"= " + parameter.ParameterName}, StringSplitOptions.RemoveEmptyEntries).Reverse().First();
var column = columnSection.Substring(columnSection.Trim().LastIndexOf(' ')).Replace("(", "");
var myCommand = string.Format("({0} = {1} OR {0} IS NULL)", column.Trim(), parameter.ParameterName);
paramindex -= (parameter.ParameterName.Length + column.Length + 1);
var orig = before.Substring(0, paramindex);
cmd.CommandText = orig + myCommand + after;
}
}
else
parameter.Value = "DI";
}
But this is NHibernate!!! Hacking the sql statement like this can't possibly be the correct way to handle this? Right?
Because it is a shared legacy database, I can't change the table schema to NOT NULL otherwise I would have just done that, and avoided this scenario.
So finally after all this prelude my question is simply this, where can I tell NHibernate to generate a custom SQL criteria statement for this IUserType?
Thank you all in advance!
Solved it!
After I posted my question I went back to the drawing board, and I came up with a solution that doesn't require hacking the generated SQL in the IUserType implementation. In fact this solution doesn't need the IUserType at all!
Here is what I did.
First, I changed the IsActive column to use a formula to handle the null checking. This fixed my issue with the QueryOver failing, because now everytime NHibernate deals with IsActive property it injects my sql formula to handle null.
The downside to this approach was that after I put in the formula all of my save tests failed. It turns out that formula properties are effectively ReadOnly properties.
So to get around this issue, I added a protected property to the entity to hold the status value from the database.
Next, I changed the IsActive property to set the protected status property to " " or "DI". And finally I changed the FluentMapping to Reveal the protected Status property to NHibernate so that NHibernate can track it. Now that NHibernate is aware of Status it can include it on its INSERT/UPDATE statements.
I am going to include my solution below in case anyone else is interested.
Client class
public class Client
{
...
protected virtual string Status { get; set; }
private bool _isActive;
public virtual bool IsActive
{
get { return _isActive; }
set
{
_isActive = value;
Status = (_isActive) ? " " : "DI";
}
}
}
Changes to Fluent Mapping
public class ClientMapping : CoreEntityMapping<Client>
{
public ClientMapping()
{
....
Map(Reveal.Member<E>("Status"), colName).Length(2);
Map(x => x.IsActive).Formula("case when clnStatus is null then ' ' else clnStatus end");
}
}
I need to restrict input into a TextField to integers. Any advice?
Very old thread, but this seems neater and strips out non-numeric characters if pasted.
// force the field to be numeric only
textField.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable, String oldValue,
String newValue) {
if (!newValue.matches("\\d*")) {
textField.setText(newValue.replaceAll("[^\\d]", ""));
}
}
});
javafx.scene.control.TextFormatter
Updated Apr 2016
This answer was created some years ago and the original answer is largely obsolete now.
Since Java 8u40, Java has a TextFormatter which is usually best for enforcing input of specific formats such as numerics on JavaFX TextFields:
Numeric TextField for Integers in JavaFX 8 with TextFormatter and/or UnaryOperator
Java 8 U40 TextFormatter (JavaFX) to restrict user input only for decimal number
String with numbers and letters to double javafx
See also other answers to this question which specifically mention TextFormatter.
Original Answer
There are some examples of this in this gist, I have duplicated one of the examples below:
// helper text field subclass which restricts text input to a given range of natural int numbers
// and exposes the current numeric int value of the edit box as a value property.
class IntField extends TextField {
final private IntegerProperty value;
final private int minValue;
final private int maxValue;
// expose an integer value property for the text field.
public int getValue() { return value.getValue(); }
public void setValue(int newValue) { value.setValue(newValue); }
public IntegerProperty valueProperty() { return value; }
IntField(int minValue, int maxValue, int initialValue) {
if (minValue > maxValue)
throw new IllegalArgumentException(
"IntField min value " + minValue + " greater than max value " + maxValue
);
if (!((minValue <= initialValue) && (initialValue <= maxValue)))
throw new IllegalArgumentException(
"IntField initialValue " + initialValue + " not between " + minValue + " and " + maxValue
);
// initialize the field values.
this.minValue = minValue;
this.maxValue = maxValue;
value = new SimpleIntegerProperty(initialValue);
setText(initialValue + "");
final IntField intField = this;
// make sure the value property is clamped to the required range
// and update the field's text to be in sync with the value.
value.addListener(new ChangeListener<Number>() {
#Override public void changed(ObservableValue<? extends Number> observableValue, Number oldValue, Number newValue) {
if (newValue == null) {
intField.setText("");
} else {
if (newValue.intValue() < intField.minValue) {
value.setValue(intField.minValue);
return;
}
if (newValue.intValue() > intField.maxValue) {
value.setValue(intField.maxValue);
return;
}
if (newValue.intValue() == 0 && (textProperty().get() == null || "".equals(textProperty().get()))) {
// no action required, text property is already blank, we don't need to set it to 0.
} else {
intField.setText(newValue.toString());
}
}
}
});
// restrict key input to numerals.
this.addEventFilter(KeyEvent.KEY_TYPED, new EventHandler<KeyEvent>() {
#Override public void handle(KeyEvent keyEvent) {
if(intField.minValue<0) {
if (!"-0123456789".contains(keyEvent.getCharacter())) {
keyEvent.consume();
}
}
else {
if (!"0123456789".contains(keyEvent.getCharacter())) {
keyEvent.consume();
}
}
}
});
// ensure any entered values lie inside the required range.
this.textProperty().addListener(new ChangeListener<String>() {
#Override public void changed(ObservableValue<? extends String> observableValue, String oldValue, String newValue) {
if (newValue == null || "".equals(newValue) || (intField.minValue<0 && "-".equals(newValue))) {
value.setValue(0);
return;
}
final int intValue = Integer.parseInt(newValue);
if (intField.minValue > intValue || intValue > intField.maxValue) {
textProperty().setValue(oldValue);
}
value.set(Integer.parseInt(textProperty().get()));
}
});
}
}
I know this is a rather old thread, but for future readers here is another solution I found quite intuitive:
public class NumberTextField extends TextField
{
#Override
public void replaceText(int start, int end, String text)
{
if (validate(text))
{
super.replaceText(start, end, text);
}
}
#Override
public void replaceSelection(String text)
{
if (validate(text))
{
super.replaceSelection(text);
}
}
private boolean validate(String text)
{
return text.matches("[0-9]*");
}
}
Edit: Thanks none_ and SCBoy for your suggested improvements.
Starting with JavaFX 8u40, you can set a TextFormatter object on a text field:
UnaryOperator<Change> filter = change -> {
String text = change.getText();
if (text.matches("[0-9]*")) {
return change;
}
return null;
};
TextFormatter<String> textFormatter = new TextFormatter<>(filter);
fieldNport = new TextField();
fieldNport.setTextFormatter(textFormatter);
This avoids both subclassing and duplicate change events which you will get when you add a change listener to the text property and modify the text in that listener.
The TextInput has a TextFormatter which can be used to format, convert and limit the types of text that can be input.
The TextFormatter has a filter which can be used to reject input. We need to set this to reject anything that's not a valid integer. It also has a converter which we need to set to convert the string value to an integer value which we can bind later on.
Lets create a reusable filter:
public class IntegerFilter implements UnaryOperator<TextFormatter.Change> {
private final static Pattern DIGIT_PATTERN = Pattern.compile("\\d*");
#Override
public Change apply(TextFormatter.Change aT) {
return DIGIT_PATTERN.matcher(aT.getText()).matches() ? aT : null;
}
}
The filter can do one of three things, it can return the change unmodified to accept it as it is, it can alter the change in some way it deems fit or it can return null to reject the change all together.
We will use the standard IntegerStringConverter as a converter.
Putting it all together we have:
TextField textField = ...;
TextFormatter<Integer> formatter = new TextFormatter<>(
new IntegerStringConverter(), // Standard converter form JavaFX
defaultValue,
new IntegerFilter());
formatter.valueProperty().bindBidirectional(myIntegerProperty);
textField.setTextFormatter(formatter);
If you want don't need a reusable filter you can do this fancy one-liner instead:
TextFormatter<Integer> formatter = new TextFormatter<>(
new IntegerStringConverter(),
defaultValue,
c -> Pattern.matches("\\d*", c.getText()) ? c : null );
I don't like exceptions thus I used the matches function from String-Class
text.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable, String oldValue,
String newValue) {
if (newValue.matches("\\d*")) {
int value = Integer.parseInt(newValue);
} else {
text.setText(oldValue);
}
}
});
Starting from Java SE 8u40, for such need you can use an "integer" Spinner allowing to safely select a valid integer by using the keyboard's up arrow/down arrow keys or the up arrow/down arrow provided buttons.
You can also define a min, a max and an initial value to limit the allowed values and an amount to increment or decrement by, per step.
For example
// Creates an integer spinner with 1 as min, 10 as max and 2 as initial value
Spinner<Integer> spinner1 = new Spinner<>(1, 10, 2);
// Creates an integer spinner with 0 as min, 100 as max and 10 as initial
// value and 10 as amount to increment or decrement by, per step
Spinner<Integer> spinner2 = new Spinner<>(0, 100, 10, 10);
Example of result with an "integer" spinner and a "double" spinner
A spinner is a single-line text field control that lets the user
select a number or an object value from an ordered sequence of such
values. Spinners typically provide a pair of tiny arrow buttons for
stepping through the elements of the sequence. The keyboard's up
arrow/down arrow keys also cycle through the elements. The user may
also be allowed to type a (legal) value directly into the spinner.
Although combo boxes provide similar functionality, spinners are
sometimes preferred because they don't require a drop-down list that
can obscure important data, and also because they allow for features
such as wrapping from the maximum value back to the minimum value
(e.g., from the largest positive integer to 0).
More details about the Spinner control
The preffered answer can be even smaller if you make use of Java 1.8 Lambdas
textfield.textProperty().addListener((observable, oldValue, newValue) -> {
if (newValue.matches("\\d*")) return;
textfield.setText(newValue.replaceAll("[^\\d]", ""));
});
I want to help with my idea from combining Evan Knowles answer with TextFormatter from JavaFX 8
textField.setTextFormatter(new TextFormatter<>(c -> {
if (!c.getControlNewText().matches("\\d*"))
return null;
else
return c;
}
));
so good luck ;) keep calm and code java
TextField text = new TextField();
text.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable,
String oldValue, String newValue) {
try {
Integer.parseInt(newValue);
if (newValue.endsWith("f") || newValue.endsWith("d")) {
manualPriceInput.setText(newValue.substring(0, newValue.length()-1));
}
} catch (ParseException e) {
text.setText(oldValue);
}
}
});
The if clause is important to handle inputs like 0.5d or 0.7f which are correctly parsed by Int.parseInt(), but shouldn't appear in the text field.
Try this simple code it will do the job.
DecimalFormat format = new DecimalFormat( "#.0" );
TextField field = new TextField();
field.setTextFormatter( new TextFormatter<>(c ->
{
if ( c.getControlNewText().isEmpty() )
{
return c;
}
ParsePosition parsePosition = new ParsePosition( 0 );
Object object = format.parse( c.getControlNewText(), parsePosition );
if ( object == null || parsePosition.getIndex() < c.getControlNewText().length() )
{
return null;
}
else
{
return c;
}
}));
If you want to apply the same listener to more than one TextField here is the simplest solution:
TextField txtMinPrice, txtMaxPrice = new TextField();
ChangeListener<String> forceNumberListener = (observable, oldValue, newValue) -> {
if (!newValue.matches("\\d*"))
((StringProperty) observable).set(oldValue);
};
txtMinPrice.textProperty().addListener(forceNumberListener);
txtMaxPrice.textProperty().addListener(forceNumberListener);
This one worked for me.
public void RestrictNumbersOnly(TextField tf){
tf.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable, String oldValue,
String newValue) {
if (!newValue.matches("|[-\\+]?|[-\\+]?\\d+\\.?|[-\\+]?\\d+\\.?\\d+")){
tf.setText(oldValue);
}
}
});
}
Here is a simple class that handles some basic validations on TextField, using TextFormatter introduced in JavaFX 8u40
EDIT:
(Code added regarding Floern's comment)
import java.text.DecimalFormatSymbols;
import java.util.regex.Pattern;
import javafx.beans.NamedArg;
import javafx.scene.control.TextFormatter;
import javafx.scene.control.TextFormatter.Change;
public class TextFieldValidator {
private static final String CURRENCY_SYMBOL = DecimalFormatSymbols.getInstance().getCurrencySymbol();
private static final char DECIMAL_SEPARATOR = DecimalFormatSymbols.getInstance().getDecimalSeparator();
private final Pattern INPUT_PATTERN;
public TextFieldValidator(#NamedArg("modus") ValidationModus modus, #NamedArg("countOf") int countOf) {
this(modus.createPattern(countOf));
}
public TextFieldValidator(#NamedArg("regex") String regex) {
this(Pattern.compile(regex));
}
public TextFieldValidator(Pattern inputPattern) {
INPUT_PATTERN = inputPattern;
}
public static TextFieldValidator maxFractionDigits(int countOf) {
return new TextFieldValidator(maxFractionPattern(countOf));
}
public static TextFieldValidator maxIntegers(int countOf) {
return new TextFieldValidator(maxIntegerPattern(countOf));
}
public static TextFieldValidator integersOnly() {
return new TextFieldValidator(integersOnlyPattern());
}
public TextFormatter<Object> getFormatter() {
return new TextFormatter<>(this::validateChange);
}
private Change validateChange(Change c) {
if (validate(c.getControlNewText())) {
return c;
}
return null;
}
public boolean validate(String input) {
return INPUT_PATTERN.matcher(input).matches();
}
private static Pattern maxFractionPattern(int countOf) {
return Pattern.compile("\\d*(\\" + DECIMAL_SEPARATOR + "\\d{0," + countOf + "})?");
}
private static Pattern maxCurrencyFractionPattern(int countOf) {
return Pattern.compile("^\\" + CURRENCY_SYMBOL + "?\\s?\\d*(\\" + DECIMAL_SEPARATOR + "\\d{0," + countOf + "})?\\s?\\" +
CURRENCY_SYMBOL + "?");
}
private static Pattern maxIntegerPattern(int countOf) {
return Pattern.compile("\\d{0," + countOf + "}");
}
private static Pattern integersOnlyPattern() {
return Pattern.compile("\\d*");
}
public enum ValidationModus {
MAX_CURRENCY_FRACTION_DIGITS {
#Override
public Pattern createPattern(int countOf) {
return maxCurrencyFractionPattern(countOf);
}
},
MAX_FRACTION_DIGITS {
#Override
public Pattern createPattern(int countOf) {
return maxFractionPattern(countOf);
}
},
MAX_INTEGERS {
#Override
public Pattern createPattern(int countOf) {
return maxIntegerPattern(countOf);
}
},
INTEGERS_ONLY {
#Override
public Pattern createPattern(int countOf) {
return integersOnlyPattern();
}
};
public abstract Pattern createPattern(int countOf);
}
}
You can use it like this:
textField.setTextFormatter(new TextFieldValidator(ValidationModus.INTEGERS_ONLY).getFormatter());
or you can instantiate it in a fxml file, and apply it to a customTextField with the according properties.
app.fxml:
<fx:define>
<TextFieldValidator fx:id="validator" modus="INTEGERS_ONLY"/>
</fx:define>
CustomTextField.class:
public class CustomTextField {
private TextField textField;
public CustomTextField(#NamedArg("validator") TextFieldValidator validator) {
this();
textField.setTextFormatter(validator.getFormatter());
}
}
Code on github
This is what I use:
private TextField textField;
textField.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
if(!newValue.matches("[0-9]*")){
textField.setText(oldValue);
}
}
});
The same in lambda notation would be:
private TextField textField;
textField.textProperty().addListener((observable, oldValue, newValue) -> {
if(!newValue.matches("[0-9]*")){
textField.setText(oldValue);
}
});
This method lets TextField to finish all processing (copy/paste/undo safe).
Does not require to extend classes and allows you to decide what to do with new text after every change
(to push it to logic, or turn back to previous value, or even to modify it).
// fired by every text property change
textField.textProperty().addListener(
(observable, oldValue, newValue) -> {
// Your validation rules, anything you like
// (! note 1 !) make sure that empty string (newValue.equals(""))
// or initial text is always valid
// to prevent inifinity cycle
// do whatever you want with newValue
// If newValue is not valid for your rules
((StringProperty)observable).setValue(oldValue);
// (! note 2 !) do not bind textProperty (textProperty().bind(someProperty))
// to anything in your code. TextProperty implementation
// of StringProperty in TextFieldControl
// will throw RuntimeException in this case on setValue(string) call.
// Or catch and handle this exception.
// If you want to change something in text
// When it is valid for you with some changes that can be automated.
// For example change it to upper case
((StringProperty)observable).setValue(newValue.toUpperCase());
}
);
For your case just add this logic inside. Works perfectly.
if (newValue.equals("")) return;
try {
Integer i = Integer.valueOf(newValue);
// do what you want with this i
} catch (Exception e) {
((StringProperty)observable).setValue(oldValue);
}
Mmmm. I ran into that problem weeks ago. As the API doesn't provide a control to achieve that,
you may want to use your own one. I used something like:
public class IntegerBox extends TextBox {
public-init var value : Integer = 0;
protected function apply() {
try {
value = Integer.parseInt(text);
} catch (e : NumberFormatException) {}
text = "{value}";
}
override var focused = false on replace {apply()};
override var action = function () {apply()}
}
It's used the same way that a normal TextBox,
but has also a value attribute which stores the entered integer.
When the control looses the focus, it validates the value and reverts it (if isn't valid).
this Code Make your textField Accept only Number
textField.lengthProperty().addListener((observable, oldValue, newValue) -> {
if(newValue.intValue() > oldValue.intValue()){
char c = textField.getText().charAt(oldValue.intValue());
/** Check if the new character is the number or other's */
if( c > '9' || c < '0'){
/** if it's not number then just setText to previous one */
textField.setText(textField.getText().substring(0,textField.getText().length()-1));
}
}
});
This code works fine for me even if you try to copy/paste.
myTextField.textProperty().addListener((observable, oldValue, newValue) -> {
if (!newValue.matches("\\d*")) {
myTextField.setText(oldValue);
}
});
In recent updates of JavaFX, you have to set new text in Platform.runLater method just like this:
private void set_normal_number(TextField textField, String oldValue, String newValue) {
try {
int p = textField.getCaretPosition();
if (!newValue.matches("\\d*")) {
Platform.runLater(() -> {
textField.setText(newValue.replaceAll("[^\\d]", ""));
textField.positionCaret(p);
});
}
} catch (Exception e) {
}
}
It's a good idea to set caret position too.
I would like to improve Evan Knowles answer: https://stackoverflow.com/a/30796829/2628125
In my case I had class with handlers for UI Component part. Initialization:
this.dataText.textProperty().addListener((observable, oldValue, newValue) -> this.numericSanitization(observable, oldValue, newValue));
And the numbericSanitization method:
private synchronized void numericSanitization(ObservableValue<? extends String> observable, String oldValue, String newValue) {
final String allowedPattern = "\\d*";
if (!newValue.matches(allowedPattern)) {
this.dataText.setText(oldValue);
}
}
Keyword synchronized is added to prevent possible render lock issue in javafx if setText will be called before old one is finished execution. It is easy to reproduce if you will start typing wrong chars really fast.
Another advantage is that you keep only one pattern to match and just do rollback. It is better because you can easily abstragate solution for different sanitization patterns.
rate_text.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
String s="";
for(char c : newValue.toCharArray()){
if(((int)c >= 48 && (int)c <= 57 || (int)c == 46)){
s+=c;
}
}
rate_text.setText(s);
}
});
This works fine as it allows you to enter only integer value and decimal value (having ASCII code 46).
Another very simple solution would be:
TextField tf = new TextField();
tf.addEventFilter(KeyEvent.ANY, event -> {
if (!event.getCharacter().trim().matches("\\d?")) {
event.consume();
}
});
A little late, but if you also what to include decimals:
public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
if (!newValue.matches("\\d{0,7}([\\.]\\d{0,4})?")) {
textField.setText(oldValue);
}
}