code: package io.ray.runtime.functionmanager;
  
  import com.google.common.base.Objects;
  import com.google.common.collect.ImmutableList;
  import io.ray.runtime.generated.Common.Language;
  import java.io.Serializable;
  import java.util.List;
  
  /** Represents metadata of Java function. */
  public final class JavaFunctionDescriptor implements FunctionDescriptor, Serializable {
  
    private static final long serialVersionUID = -2137471820857197094L;
  
    /** Function's class name. */
    public final String className;
    /** Function's name. */
    public final String name;
    /** Function's signature. */
    public final String signature;
  
    public JavaFunctionDescriptor(String className, String name, String signature) {
      this.className = className;
      this.name = name;
      this.signature = signature;
    }
  
    @Override
    public String toString() {
      return className + "." + name;
    }
  
    @Override
    public boolean equals(Object o) {
      if (this == o) {
        return true;
      }
      if (o == null || getClass() != o.getClass()) {
        return false;
      }
      JavaFunctionDescriptor that = (JavaFunctionDescriptor) o;
      return Objects.equal(className, that.className)
          && Objects.equal(name, that.name)
          && Objects.equal(signature, that.signature);
    }
  
    @Override
    public int hashCode() {
      return Objects.hashCode(className, name, signature);
    }
  
    @Override
    public List<String> toList() {
      return ImmutableList.of(className, name, signature);
    }
  
    @Override
    public Language getLanguage() {
      return Language.JAVA;
    }
  }
  