Java实现对象的属性打印

废话不多说，直接上代码，详细代码如下：

/** 
 *  
 * @author daimami.com 
 * 打印出对象的所有属性的工具类 
 * 使用方法示例 
 * BeanDebugger.dump(object); 
 */
public class BeanDebugger { 
    public static String outputFile = "d:/log/bean_"+System.currentTimeMillis()+".txt"; 
    public static PrintWriter pw = null;; 
    static { 
        try{ 
            //准备输出文件 
            pw = new PrintWriter(outputFile); 
        } 
        catch(Exception e){ 
            e.printStackTrace(); 
        } 
    } 
    public static void println(String s){ 
        System.out.println(s); 
//      pw.println(s); 
    } 
    
    /** 
     * 调试, 打印出给定 Bean 的所有属性的取值. 
     * @param bean 
     * @param proArray 
     *            需要打印的对象 
     */
    public static void dump(Object bean,String[] proArray) { 
        if (bean instanceof Collection) { 
            @SuppressWarnings("unchecked") 
            Collection<Object> collection = (Collection<Object>) bean; 
            println("print Collection begein!"); 
            for (Object o : collection) { 
                dump(o,proArray); 
            } 
            println("print Collection end!"); 
        } else if (bean instanceof Map) { 
            println("print Map begein!"); 
            @SuppressWarnings("unchecked") 
            Map<Object,Object> map = (Map<Object,Object>) bean; 
            for (Object o : map.keySet()) { 
                Object value = map.get(o); 
                if(isImmutableObjects(value)){ 
                    println("["+o.toString()+"]=" + value.toString()); 
                } 
                else { 
                    println("["+o.toString()+"] begin"); 
                    dump(value,proArray); 
                    println("["+o.toString()+"] end!" ); 
                } 
            } 
            println("print Map end!"); 
        } else { 
            if(isImmutableObjects(bean)){ 
                //不可变类 
                println("["+bean.getClass().getName()+"]="+bean.toString()); 
            } 
            else { 
                printObject(bean,proArray); 
            } 
        } 
    } 
    /** 
     * 判断是否是不可变类 
     * @param bean 
     * @return 
     */
    private static boolean isImmutableObjects(Object bean) { 
        if(bean instanceof Integer  
                || bean instanceof Long 
                || bean instanceof String 
                || bean instanceof Short 
                || bean instanceof Boolean 
                || bean instanceof Byte 
                || bean instanceof Character 
                || bean instanceof Double 
                || bean instanceof Float 
                || bean instanceof Number){ 
            return true; 
        } 
        return false; 
    } 
    
    
    /** 
     *  
     * 从 bean 中读取有效的属性描述符. NOTE: 名称为 class 的 PropertyDescriptor 被排除在外. 
     * @param bean 
     *            Object - 需要读取的 Bean 
     * @return PropertyDescriptor[] - 属性列表 
     */
    public static java.beans.PropertyDescriptor[] getAvailablePropertyDescriptors( 
            Object bean) { 
        try { 
            // 从 Bean 中解析属性信息并查找相关的 write 方法 
            java.beans.BeanInfo info = java.beans.Introspector.getBeanInfo(bean 
                    .getClass()); 
            if (info != null) { 
                java.beans.PropertyDescriptor pd[] = info 
                        .getPropertyDescriptors(); 
                Vector<PropertyDescriptor> columns = new Vector<PropertyDescriptor>(); 
                for (int i = 0; i < pd.length; i++) { 
                    String fieldName = pd[i].getName(); 
                    if (fieldName != null && !fieldName.equals("class")) { 
                        columns.add(pd[i]); 
                    } 
                } 
                java.beans.PropertyDescriptor[] arrays = new java.beans.PropertyDescriptor[columns 
                        .size()]; 
                for (int j = 0; j < columns.size(); j++) { 
                    arrays[j] = (PropertyDescriptor) columns.get(j); 
                } 
                return arrays; 
            } 
        } catch (Exception ex) { 
            ex.printStackTrace(); 
            return null; 
        } 
        return null; 
    
    } 
    
    public static void dump(Object bean) { 
        dump(bean,null); 
    } 
    
    private static void printObject(Object bean, String[] proArray) { 
        java.beans.PropertyDescriptor[] descriptors = getAvailablePropertyDescriptors(bean); 
        for (int i = 0; descriptors != null && i < descriptors.length; i++) { 
            java.lang.reflect.Method readMethod = descriptors[i] 
                    .getReadMethod(); 
            try { 
                String proName = descriptors[i].getName(); 
                if(proArray == null || (proArray !=null && inArray(proName,proArray))){ 
                    Object value = readMethod.invoke(bean, new Object[]{}); 
                    println("[" + bean.getClass().getName() + "]."
                            + proName + "("
                            + descriptors[i].getPropertyType().getName() + ") = "
                            + value); 
                } 
            } catch (Exception e) { 
                e.printStackTrace(); 
            } 
        } 
            
    } 
    /** 
     * 判断proName是否在proArray里面 
     * @param proName 
     * @param proArray 
     * @return 
     */
    private static boolean inArray(String proName, String[] proArray) { 
        if(proArray == null) 
            return false; 
        boolean in = false; 
        for(String s : proArray){ 
            if(proName.equals(s)){ 
                in = true; 
                break; 
            } 
        } 
        return in; 
    } 
}