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对List对象按照某个成员变量进行排序
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/**
* 对List对象按照某个成员变量进行排序
* @param list List对象
* @param sortField 排序的属性名称
* @param sortMode 排序方式：ASC，DESC 任选其一
*/
public static <T> void sortList(List<T> list, final String sortField, final String sortMode) {
Collections.sort(list, new Comparator<T>() {
@Override
public int compare(T o1, T o2) {
try {
Class clazz = o1.getClass();
Field field = clazz.getDeclaredField(sortField); //获取成员变量
field.setAccessible(true); //设置成可访问状态
String typeName = field.getType().getName().toLowerCase(); //转换成小写 Object v1 = field.get(o1); //获取field的值
Object v2 = field.get(o2); //获取field的值 boolean ASC_order = (sortMode == null || "ASC".equalsIgnoreCase(sortMode)); //判断字段数据类型，并比较大小
if(typeName.endsWith("string")) {
String value1 = v1.toString();
String value2 = v2.toString();
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("short")) {
Short value1 = Short.parseShort(v1.toString());
Short value2 = Short.parseShort(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("byte")) {
Byte value1 = Byte.parseByte(v1.toString());
Byte value2 = Byte.parseByte(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("char")) {
Integer value1 = (int)(v1.toString().charAt(0));
Integer value2 = (int)(v2.toString().charAt(0));
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("int") || typeName.endsWith("integer")) {
Integer value1 = Integer.parseInt(v1.toString());
Integer value2 = Integer.parseInt(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("long")) {
Long value1 = Long.parseLong(v1.toString());
Long value2 = Long.parseLong(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("float")) {
Float value1 = Float.parseFloat(v1.toString());
Float value2 = Float.parseFloat(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("double")) {
Double value1 = Double.parseDouble(v1.toString());
Double value2 = Double.parseDouble(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("boolean")) {
Boolean value1 = Boolean.parseBoolean(v1.toString());
Boolean value2 = Boolean.parseBoolean(v2.toString());
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("date")) {
Date value1 = (Date)(v1);
Date value2 = (Date)(v2);
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else if(typeName.endsWith("timestamp")) {
Timestamp value1 = (Timestamp)(v1);
Timestamp value2 = (Timestamp)(v2);
return ASC_order ? value1.compareTo(value2) : value2.compareTo(value1);
}
else {
//调用对象的compareTo()方法比较大小
Method method = field.getType().getDeclaredMethod("compareTo", new Class[]{field.getType()});
method.setAccessible(true); //设置可访问权限
int result = (Integer)method.invoke(v1, new Object[]{v2});
return ASC_order ? result : result*(-1);
}
}
catch (Exception e) {
String err = e.getLocalizedMessage();
System.out.println(err);
e.printStackTrace();
} return 0; //未知类型，无法比较大小
}
});
}
