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copied!<p>You can use the following method for check if the attribute of an Object is null or has default value:</p> <pre><code>public static boolean isNullOrDefaultValue(Field field, Object obj) throws Exception { boolean result = false; if(!field.getType().isPrimitive()) { if (field.get(obj) == null) { result = true; } } else{ Class objClass = field.getType(); if (int.class.equals(objClass) || long.class.equals(objClass) || short.class.equals(objClass) || byte.class.equals(objClass)) { if (field.getLong(obj) == 0) { result = true; } } else if(float.class.equals(objClass) || double.class.equals(objClass)) { if (field.getDouble(obj) == 0.0D) { result = true; } } else if(boolean.class.equals(objClass)) { if (field.getBoolean(obj) == false) { result = true; } } else if (char.class.equals(objClass)) { if (field.getChar(obj) == '\u0000') { result = true; } } } return result; } </code></pre> <p>Here is a sample usage. If we have the following class:</p> <pre><code>class ClassA { public int intValue; public short shortValue; public byte byteValue; public long longValue; public float floatValue; public double doubleValue; public char charValue; public boolean booleanValue; public String stringValue; } </code></pre> <p>So we can test in a main method as follows:</p> <pre><code>public static void main(String[] args) throws Exception { Class aClass = ClassA.class; Object aInst = new ClassA(); Field[] fields = aClass.getFields(); for (int i = 0; i < fields.length; i++) { Field field = fields[i]; System.out.println("Name: " + field.getName() + " Eval:" + isNullOrDefaultValue(field, aInst)); } } </code></pre> <p>The result will be:</p> <pre><code>Name: intValue Eval:true Name: shortValue Eval:true Name: byteValue Eval:true Name: longValue Eval:true Name: floatValue Eval:true Name: doubleValue Eval:true Name: charValue Eval:true Name: booleanValue Eval:true Name: stringValue Eval:true </code></pre>

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