Check Binary Tree is Strict Binary Search Tree

A strict Binary Tree is a type of Binary Tree where duplicates are not allowed.

package org.wesome.dsalgo;

import lombok.Data;

import java.util.Objects;

public class BinarySearchTree {
    Node root;

    boolean isStrictBinarySearchTree(Node node, int min, int max) {
        if (node == null) {
            return true;
        }
        /* Node value should always be greater than min and smaller then maximum */
        if (node.data < min || node.data > max) {
            return false;
        }
        return (isStrictBinarySearchTree(node.left, min, node.data - 1) && isStrictBinarySearchTree(node.right, node.data + 1, max));
    }

    void insert(int data) {
        System.out.println("BinarySearchTree.insert data = " + data);
        root = insert(root, data);
    }

    Node insert(Node root, int data) {
        if (Objects.isNull(root)) {
            Node tempNode = new Node(data);
            return tempNode;
        }
        if (data > root.data) {
            root.right = insert(root.right, data);
        } else {
            root.left = insert(root.left, data);
        }
        return root;
    }
}

@Data
class Node {
    int data;
    Node left, right;

    public Node(int data) {
        this.data = data;
        left = right = null;
    }
}

package org.wesome.dsalgo;

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

public class BinarySearchTreeTest {
    @Test
    void isStrictBinarySearchTreeTest() {
        BinarySearchTree binarySearchTree = new BinarySearchTree();
        binarySearchTree.insert(4);
        binarySearchTree.insert(2);
        binarySearchTree.insert(1);
        binarySearchTree.insert(3);
        binarySearchTree.insert(6);
        binarySearchTree.insert(5);
        binarySearchTree.insert(7);
        Assertions.assertTrue(binarySearchTree.isStrictBinarySearchTree(binarySearchTree.root, Integer.MIN_VALUE, Integer.MAX_VALUE));
    }
}

plugins {
    id 'java'
    id "io.freefair.lombok" version "6.2.0"
}

group = 'org.wesome'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = JavaVersion.VERSION_1_8

configurations {
    compileOnly {
        extendsFrom annotationProcessor
    }
}

repositories {
    mavenCentral()
}

dependencies {
    testImplementation 'org.junit.jupiter:junit-jupiter:5.6.2'
}

test {
    useJUnitPlatform()
}