Resolve parameterized collection types

To resolve a parameterized collection type like List<String> in java-classmate, you use the resolve method of the TypeResolver class. This method accepts a base class and an array of type parameters to produce a ResolvedType instance that preserves generic information. You can then verify the structure of the resolved type using the getBriefDescription method.

The following example demonstrates how to instantiate a TypeResolver, resolve a List with a String type parameter, and assert that the resulting description matches the expected fully-qualified generic signature.

import com.fasterxml.classmate.ResolvedType;
import com.fasterxml.classmate.TypeResolver;
import java.util.List;

public final class ResolveParameterizedTypes {
    public static void main(String[] args) {
        TypeResolver typeResolver = new TypeResolver();

        // Resolve List<String> by providing the base class and the parameter class
        ResolvedType resolvedType = typeResolver.resolve(List.class, String.class);

        // Retrieve the human-readable brief description of the resolved type
        String briefDescription = resolvedType.getBriefDescription();

        // Verify that the resolved type matches the expected generic signature
        if (!briefDescription.equals("java.util.List<java.lang.String>")) {
            throw new AssertionError("Expected java.util.List<java.lang.String> but got: " + briefDescription);
        }
    }
}

Type Resolution Behavior

When TypeResolver.resolve is called with List.class and String.class, java-classmate performs the following:

• It identifies List as the erased base type.
• It binds the String class as the first type parameter for the List interface.
• It returns a ResolvedType implementation that encapsulates these bindings.

The ResolvedType.getBriefDescription method provides a deterministic string representation of this resolution, including the fully-qualified names of both the container and its type parameters.