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javacode-generationjavapoet

How to add the 'Any Type' questionmark in JavaPoet?


I'm generating code with JavaPoet.

Somewhere in the generated code I want to add a method which has the following argument.

...
    public B someMethod(final AbstractObjectBuilder<Persoon,?> builder) {
       ...
    }
...

So my JavaPoet code should look something like this

    //This does not compile, since I don't know what to put as last argument (questionmark)
ParameterizedTypeName parameterizedTypeName = ParameterizedTypeName.get(AbstractObjectBuilder.class, propertyType,?);

ParameterSpec parameterSpec = ParameterSpec.builder(parameterizedTypeName, name+"Builder", Modifier.FINAL).build();

MethodSpec modMethod = MethodSpec.methodBuilder(name)
                        .addModifiers(Modifier.PUBLIC)
                        .addParameter(parameterSpec)
                        .returns(TypeVariableName.get("B"));
...

Solution

  • Foo<?> is a short form of Foo<? extends Object>. Use WildcardTypeName for this.