Graph.java

import java.util.List;

public class Graph {
  public void addNode(String src) {

  }

  public void addEdge(String src, String dst) {

  }

  public void removeEdge(String src, String dst) {

  }

  public boolean hasEdge(String src, String dst) {
    return false;
  }

  public List<String> outEdges(String src) {
    return null;
  }

  public List<String> inEdges(String src) {
    return null;
  }

  public List<String> bfs(String src) {
    return null;
  }

  public List<String> dfs(String src) {
    return null;
  }
}

GraphTest.java

import org.junit.Test;

public class GraphTest {
  @Test
  public void addNode() throws Exception {

  }

  @Test
  public void addEdge() throws Exception {

  }

  @Test
  public void removeEdge() throws Exception {

  }

  @Test
  public void hasEdge() throws Exception {

  }

  @Test
  public void outEdges() throws Exception {

  }

  @Test
  public void inEdges() throws Exception {

  }

  @Test
  public void bfs() throws Exception {

  }

  @Test
  public void dfs() throws Exception {

  }

}