ParseResult.java

package org.springframework.roo.shell;

import java.lang.reflect.Method;
import java.util.Arrays;

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
import org.apache.commons.lang3.builder.ToStringBuilder;

/**
 * Immutable representation of the outcome of parsing a given shell line.
 * <p>
 * Note that contained objects (the instance and the arguments) may be mutable,
 * as the shell infrastructure has no way of restricting which methods can be
 * the target of CLI commands and nor the arguments they will accept via the
 * {@link Converter} infrastructure.
 * 
 * @author Ben Alex
 * @since 1.0
 */
public class ParseResult {

  private final Object[] arguments; // May be null if no arguments needed
  private final Object instance;
  private final Method method;

  public ParseResult(final Method method, final Object instance, final Object[] arguments) {
    Validate.notNull(method, "Method required");
    Validate.notNull(instance, "Instance required");
    final int length = arguments == null ? 0 : arguments.length;
    Validate.isTrue(method.getParameterTypes().length == length,
        "Required %d arguments, but received %d", method.getParameterTypes().length, length);
    this.method = method;
    this.instance = instance;
    this.arguments = arguments;
  }

  @Override
  public boolean equals(final Object obj) {
    if (this == obj) {
      return true;
    }
    if (obj == null) {
      return false;
    }
    if (getClass() != obj.getClass()) {
      return false;
    }
    final ParseResult other = (ParseResult) obj;
    if (!Arrays.equals(arguments, other.arguments)) {
      return false;
    }
    if (instance == null) {
      if (other.instance != null) {
        return false;
      }
    } else if (!instance.equals(other.instance)) {
      return false;
    }
    if (method == null) {
      if (other.method != null) {
        return false;
      }
    } else if (!method.equals(other.method)) {
      return false;
    }
    return true;
  }

  public Object[] getArguments() {
    return arguments;
  }

  public Object getInstance() {
    return instance;
  }

  public Method getMethod() {
    return method;
  }

  @Override
  public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + Arrays.hashCode(arguments);
    result = prime * result + (instance == null ? 0 : instance.hashCode());
    result = prime * result + (method == null ? 0 : method.hashCode());
    return result;
  }

  @Override
  public String toString() {
    final ToStringBuilder builder = new ToStringBuilder(this);
    builder.append("method", method);
    builder.append("instance", instance);
    builder.append("arguments", StringUtils.join(arguments, ","));
    return builder.toString();
  }
}