這篇文章主要介紹了java基於反射得到物件屬性值的方法,結合實例形式分析了java基於反射獲取物件屬性值的相關實現方法與操作技巧,需要的朋友可以參考下
本文實例講述了java基於反射得到物件屬性值的方法。分享給大家供大家參考,具體如下:
透過反射機制得到物件中的屬性和屬性值 在物件中private沒問題,在別的類別中有時會報異常。下面的例子是在本物件中
/** * Engine entity. @author MyEclipse Persistence Tools */ public class Engine implements java.io.Serializable { // Fields private Long engineId; private String engineName; private String engineType; // Constructors /** default constructor */ public Engine() { } /** minimal constructor */ public Engine(Long engineId) { this.engineId = engineId; } public Engine(String engineName, String engineType) { this.engineName = engineName; this.engineType = engineType; } /** full constructor */ public Engine(Long engineId, String engineName, String engineType) { this.engineId = engineId; this.engineName = engineName; this.engineType = engineType; } // Property accessors public Long getEngineId() { return this.engineId; } public void setEngineId(Long engineId) { this.engineId = engineId; } public String getEngineName() { return this.engineName; } public void setEngineName(String engineName) { this.engineName = engineName; } public String getEngineType() { return this.engineType; } public void setEngineType(String engineType) { this.engineType = engineType; } public static void main(String[] args) throws Exception { Engine m = new Engine("汽车","发动机"); Class clazz = m.getClass(); Field[] f = clazz.getDeclaredFields(); String[] name = field2Name(f); Object[] value = field2Value(f, m); showNameAndValue(name, value); } public static void showNameAndValue(String[] name, Object[] value) { for (int i = 0; i < name.length; i++) { System.out.println("--" + i + "--"); System.out.println("name:" + name[i]); System.out.println("Value:" + value[i]); System.out.println("-- --"); } } public static String[] field2Name(Field[] f) { String[] name = new String[f.length]; for (int i = 0; i < f.length; i++) { name[i] = f[i].getName(); } return name; } public static Object[] field2Value(Field[] f, Object o) throws Exception { Object[] value = new Object[f.length]; for (int i = 0; i < f.length; i++) { value[i] = f[i].get(o); } return value; } }
如果想呼叫private的屬性的屬性值,則要呼叫他的get方法了具體做法是:
把field2Value方法改為如下方式,這樣在別的類別中也可以得到private的屬性值了
public static Object[] field2Value(Field[] fields, Object o) throws Exception { Object[] values = new Object[fields.length]; Class classType = o.getClass(); for (int i = 0; i < fields.length; i++) { String fieldName = fields[i].getName(); String firstLetter = fieldName.substring(0, 1).toUpperCase(); String getMethodName = "get" + firstLetter + fieldName.substring(1); Method getMethod = classType.getMethod(getMethodName, new Class[] {}); values[i] = getMethod.invoke(o, new Object[] {}); } return values; }
以上是java基於反射得到物件屬性值的範例程式碼分享的詳細內容。更多資訊請關注PHP中文網其他相關文章!