重构观后感(一)

第二版，第一章中的，java的重构的代码

package com.ruoyi.blog.controller;

import java.math.BigDecimal;
import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

import lombok.Data;
import lombok.extern.slf4j.Slf4j;

@Slf4j
public class RebuildC1 {

  private Invoice invoice;

  public RebuildC1 () {
    List<Performance> performances = new LinkedList<>();
    performances.add(new Performance("hamlet", 12));
    performances.add(new Performance("as-like", 35));
    performances.add(new Performance("othello", 40));
    invoice = new Invoice("BigCo", performances);
  }

  public static void main (String[] args) {
    RebuildC1 rebuildC1 = new RebuildC1();
    rebuildC1.statement();
  }


  public void statement () {
    StringBuilder result = new StringBuilder("Statement for ").append(invoice.customer).append("\n");
    invoice.performances.forEach(performance -> {
      result.append(" play name :").append(performance.playID).append(";");
      result.append(" audience is :").append(performance.audience).append(";");
      result.append(" credits is :").append(getThisCredit(performance)).append(";");
      result.append(" cost is :").append(getThisAmount(performance)).append(";").append("\n");
    });
    result.append("total cost :").append(forTotalAmount(invoice.performances)).append("\n");
    result.append("total earn credits :").append(forTotalCredits(invoice.performances));
    log.info(result.toString());
  }

  private int forTotalCredits (List<Performance> performances) {
    AtomicInteger volumeCredits = new AtomicInteger();
    performances.forEach(performance -> {
      volumeCredits.addAndGet(getThisCredit(performance));
    });
    return volumeCredits.get();
  }

  private int forTotalAmount (List<Performance> performances) {
    AtomicInteger totalAmount = new AtomicInteger();
    performances.forEach(performance -> {
      totalAmount.addAndGet(getThisAmount(performance));
    });
    return totalAmount.get();
  }

  private int getThisCredit (Performance performance) {
    int credits = Math.max(performance.audience - 30, 0);
    if ("comedy".equals(Plays.getTypeByName(performance.playID))) {
      credits += (int) Math.floor(new BigDecimal(performance.audience).divide(new BigDecimal(5)).intValue());
    }
    return credits;
  }

  private int getThisAmount (Performance aPerformance) {
    int result = 0;
    switch (Plays.getTypeByName(aPerformance.playID)) {
      case "tragedy":
        result = 40000;
        if (aPerformance.audience > 30) {
          result += 1000 * (aPerformance.audience - 30);
        }
        break;
      case "comedy":
        result = 30000;
        if (aPerformance.audience > 20) {
          result += 500 * (aPerformance.audience - 20);
        }
        break;
      default:
        log.error("unknown plays type:{}", Plays.getTypeByName(aPerformance.playID));
    }
    return result;
  }


  @Data
  private static class Invoice {

    Invoice (String customer, List<Performance> performances) {
      this.customer = customer;
      this.performances = performances;
    }

    String customer;
    List<Performance> performances;

  }

  @Data
  private static class Performance {

    Performance (String playID, int audience) {
      this.playID = playID;
      this.audience = audience;
    }

    String playID;
    int audience;
  }


  private enum Plays {
    HAMLET("Hamlet", "tragedy"),
    AS_LIKE("as-like", "comedy"),
    OTHELLO("Othello", "tragedy");

    String name;
    String type;

    Plays (String name, String type) {
      this.name = name;
      this.type = type;
    }


    public static String getTypeByName (String name) {
      for (Plays plays : values()) {
        if (plays.name.equals(name)) {
          return plays.type;
        }
      }
      return "comedy";
    }
  }

}