如何使用多个sorting条件对ArrayList进行sorting？

我有一个包含Quote对象的数组列表。 我希望能够按字母顺序sorting，按名称sorting，按更改sorting，并按百分比sorting。 我怎样才能sorting我的数据列表？

package org.stocktwits.model; import java.io.Serializable; import java.text.DecimalFormat; public class Quote implements Serializable { private static final long serialVersionUID = 1L; public String symbol; public String name; public String change; public String percentChange; public String open; public String daysHigh; public String daysLow; public String dividendYield; public String volume; public String averageDailyVolume; public String peRatio; public String marketCapitalization; public String yearHigh; public String yearLow; public String lastTradePriceOnly; public DecimalFormat df = new DecimalFormat("#,###,###,###,###,##0.00"); public DecimalFormat vf = new DecimalFormat("#,###,###,###,###,##0"); public String getSymbol() { return symbol; } public void setSymbol(String symbol) { this.symbol = symbol; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getChange() { return change; } public void setChange(String change) { if(change.equals("null")){ this.change = "N/A"; } else{ float floatedChange = Float.valueOf(change); this.change = (df.format(floatedChange)); } } public String getPercentChange() { return percentChange; } public void setPercentChange(String percentChange) { if(percentChange.equals("null")) percentChange = "N/A"; else this.percentChange = percentChange; } public String getOpen() { return open; } public void setOpen(String open) { if(open.equals("null")) this.open = "N/A"; else this.open = open; } public String getDaysHigh() { return daysHigh; } public void setDaysHigh(String daysHigh) { if(daysHigh.equals("null")) this.daysHigh = "N/A"; else{ float floatedDaysHigh = Float.valueOf(daysHigh); this.daysHigh = (df.format(floatedDaysHigh)); } } public String getDaysLow() { return daysLow; } public void setDaysLow(String daysLow) { if(daysLow.equals("null")) this.daysLow = "N/A"; else{ float floatedDaysLow = Float.valueOf(daysLow); this.daysLow = (df.format(floatedDaysLow)); } } public String getVolume() { return volume; } public void setVolume(String volume) { if(volume.equals("null")){ this.volume = "N/A"; } else{ float floatedVolume = Float.valueOf(volume); this.volume = (vf.format(floatedVolume)); } } public String getDividendYield() { return dividendYield; } public void setDividendYield(String dividendYield) { if(dividendYield.equals("null")) this.dividendYield = "N/A"; else this.dividendYield = dividendYield; } public String getAverageDailyVolume() { return averageDailyVolume; } public void setAverageDailyVolume(String averageDailyVolume) { if(averageDailyVolume.equals("null")){ this.averageDailyVolume = "N/A"; } else{ float floatedAverageDailyVolume = Float.valueOf(averageDailyVolume); this.averageDailyVolume = (vf.format(floatedAverageDailyVolume)); } } public String getPeRatio() { return peRatio; } public void setPeRatio(String peRatio) { if(peRatio.equals("null")) this.peRatio = "N/A"; else this.peRatio = peRatio; } public String getMarketCapitalization() { return marketCapitalization; } public void setMarketCapitalization(String marketCapitalization) { if(marketCapitalization.equals("null")) this.marketCapitalization = "N/A"; else this.marketCapitalization = marketCapitalization; } public String getYearHigh() { return yearHigh; } public void setYearHigh(String yearHigh) { if(yearHigh.equals("null")) this.yearHigh = "N/A"; else this.yearHigh = yearHigh; } public String getYearLow() { return yearLow; } public void setYearLow(String yearLow) { if(yearLow.equals("null")) this.yearLow = "N/A"; else this.yearLow = yearLow; } public String getLastTradePriceOnly() { return lastTradePriceOnly; } public void setLastTradePriceOnly(String lastTradePriceOnly) { if(lastTradePriceOnly.equals("null")){ this.lastTradePriceOnly = "N/A"; } else{ float floatedLastTradePriceOnly = Float.valueOf(lastTradePriceOnly); this.lastTradePriceOnly = (df.format(floatedLastTradePriceOnly)); } } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((change == null) ? 0 : change.hashCode()); result = prime * result + ((daysHigh == null) ? 0 : daysHigh.hashCode()); result = prime * result + ((daysLow == null) ? 0 : daysLow.hashCode()); result = prime * result + ((lastTradePriceOnly == null) ? 0 : lastTradePriceOnly .hashCode()); result = prime * result + ((marketCapitalization == null) ? 0 : marketCapitalization .hashCode()); result = prime * result + ((name == null) ? 0 : name.hashCode()); result = prime * result + ((open == null) ? 0 : open.hashCode()); result = prime * result + ((peRatio == null) ? 0 : peRatio.hashCode()); result = prime * result + ((percentChange == null) ? 0 : percentChange.hashCode()); result = prime * result + ((symbol == null) ? 0 : symbol.hashCode()); result = prime * result + ((volume == null) ? 0 : volume.hashCode()); result = prime * result + ((yearHigh == null) ? 0 : yearHigh.hashCode()); result = prime * result + ((yearLow == null) ? 0 : yearLow.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Quote other = (Quote) obj; if (change == null) { if (other.change != null) return false; } else if (!change.equals(other.change)) return false; if (daysHigh == null) { if (other.daysHigh != null) return false; } else if (!daysHigh.equals(other.daysHigh)) return false; if (daysLow == null) { if (other.daysLow != null) return false; } else if (!daysLow.equals(other.daysLow)) return false; if (lastTradePriceOnly == null) { if (other.lastTradePriceOnly != null) return false; } else if (!lastTradePriceOnly.equals(other.lastTradePriceOnly)) return false; if (marketCapitalization == null) { if (other.marketCapitalization != null) return false; } else if (!marketCapitalization.equals(other.marketCapitalization)) return false; if (name == null) { if (other.name != null) return false; } else if (!name.equals(other.name)) return false; if (open == null) { if (other.open != null) return false; } else if (!open.equals(other.open)) return false; if (peRatio == null) { if (other.peRatio != null) return false; } else if (!peRatio.equals(other.peRatio)) return false; if (percentChange == null) { if (other.percentChange != null) return false; } else if (!percentChange.equals(other.percentChange)) return false; if (symbol == null) { if (other.symbol != null) return false; } else if (!symbol.equals(other.symbol)) return false; if (volume == null) { if (other.volume != null) return false; } else if (!volume.equals(other.volume)) return false; if (yearHigh == null) { if (other.yearHigh != null) return false; } else if (!yearHigh.equals(other.yearHigh)) return false; if (yearLow == null) { if (other.yearLow != null) return false; } else if (!yearLow.equals(other.yearLow)) return false; return true; } } 

Answer 1

创build一个适当的Comparator ，将比较两个项目根据您所需的标准。 然后在你的ArrayList上使用Collections.sort() 。

如果稍后您想按不同的标准sorting，请使用不同的Comparator再次调用Collections.sort() 。

Answer 2

如果您（几乎）总是要使用该订单，则可以将Comparable界面添加到报价并实施compareTo方法。

  public int compareTo(Quote quote) { int result = this.getName().compareTo(quote.getName()); if (result == 0) { result = this.getChange().compareTo(quote.getChange()); } if (result == 0) { result = this.getPercentChange().compareTo(quote.getPercentChange()); } return result; } 

然后使用sorting后的集合，或者对列表进行sorting，然后引号将被sorting。

对于临时sorting，单独的，可能是匿名的比较器更好。

Answer 3

每个人都是正确的，你想使用比较器。 扩展这个想法，如果你想能够按照多个标准进行sorting，那么类似这样的类将适用于你：

 public class MultiComparator<T> implements Comparator<T> { private List<Comparator<T>> comparators; public MultiComparator(List<Comparator<T>> comparators) { this.comparators = comparators; } public int compare(T o1, T o2) { for (Comparator<T> comparator : comparators) { int comparison = comparator.compare(o1, o2); if (comparison != 0) return comparison; } return 0; } } 

那么你只需要为你想要的任何领域写简单的比较器，你就可以更容易地将它们组合成更复杂的比较器，并且可以重复使用。

Answer 4

看看Apache Commons Collection的ComparatorChain。 这应该做的工作。 如果已经可用并经过testing，则不要执行逻辑。
在下面的网站我有一个教程： 通过多个属性sorting对象“

Answer 5

Sun已经将大部分教程用于Java集合中的sorting：
http://download.oracle.com/javase/tutorial/collections/interfaces/order.html

它用例子讨论了Comparable和Comparator接口。

Answer 6

使用显式比较器（或者需要input来实现Comparable的Collections.sorttypes）可以看到Collections.sort ，如果您愿意的话。