Pass the optional and required parameters as per the official API docs. See the DTO reference below for more information. 
package com.example.myapp;

import com.unkey.unkeysdk.dto.KeyVerifyRequest;
import com.unkey.unkeysdk.dto.KeyVerifyResponse;

@RestController
public class APIController {

    private static IKeyService keyService = new KeyService();

    @PostMapping("/verify")
    public KeyVerifyResponse verifyKey(
            @RequestBody KeyVerifyRequest keyVerifyRequest) {
        // Delegate the creation of the key to the KeyService from the SDK
        return keyService.verifyKey(keyVerifyRequest);
    }
}

​
DTOs Reference

The DTOs used in the code for a better understanding of request and response bodies. 
public class KeyVerifyResponse {
    @NonNull
    private Boolean valid;
    private String code;
    private String ownerId;
    private Long expires;
    private Object meta;
    private KeyVerifyRateLimit ratelimit;
    private Long remaining;
}

public class KeyVerifyRateLimit {
    private Integer limit;
    private Integer remaining;
    private Long reset;
}

public class KeyVerifyRequest {
    @NonNull
    private String key;
    private String apiId;
}