[转]java 通过反射获取类的全局变量、方法、构造…

2019-12-06 16:04:34来源：博客园阅读 ()

[转]java 通过反射获取类的全局变量、方法、构造方法

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 package com.str; public class ZiFuChuan { public static String ss = "全局变量!!!!!!"; String s2 = null; public int aa = 1 ; int aa2; double dou = 1.1; Double d = new Double(1.1); public static void main(String[] args) {} public ZiFuChuan(){} public ZiFuChuan(String st){} public ZiFuChuan(int orgInt,String orgString){} public static void tmpArr(int a[],String s,StringBuffer s2){} }

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 package com.fanshe; import java.lang.reflect.Constructor; import java.lang.reflect.Field; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.lang.reflect.Type; import com.str.ZiFuChuan; public class GetClass { public static void main(String[] args) throws IllegalArgumentException, IllegalAccessException, InstantiationException { // TODO Auto-generated method stub Class classS = ZiFuChuan.class; //获取包 Package classPackage = classS.getPackage(); System.out.println("package "+classPackage.getName()); //获取类的修饰符 int mod = classS.getModifiers(); String classModifier = Modifier.toString(mod); System.out.println(classModifier + " class ZiFuChuan {"); //调用全局变量方法 getFieldContent(classS); //调用构造方法 getConstructorContent(classS); //调用其他方法 getMethodContent(classS); System.out.println("}"); } /** * 获取所有全局变量 * @param classS * @throws IllegalAccessException * @throws IllegalArgumentException * @throws InstantiationException */ public static void getFieldContent(Class classS) throws IllegalArgumentException, IllegalAccessException, InstantiationException{ String typeName = ""; Field[] field = classS.getDeclaredFields(); for(Field fi : field){ typeName = fi.getType().getName(); String xsfTmp = Modifier.toString(fi.getModifiers()) ; //全局变量有修饰符的在变量前加修饰符并且修饰符和数据类型之间用空格分隔,否则不需要加空格 String xiushifu = xsfTmp.length() == 0 ? "" : xsfTmp + " "; String value = getValue(typeName,fi,classS); if("null".equals(value)||value == null||"null;".equals(value)){ System.out.println(" "+xiushifu+typeName+" "+fi.getName()+"; "); }else{ System.out.println(" "+xiushifu+typeName+" "+fi.getName()+" = " + getValue(typeName,fi,classS)); } } } public static void getConstructorContent(Class classS){ Constructor[] con = classS.getConstructors(); for(Constructor c : con){ int mod = c.getModifiers(); String ConstructorModifier = Modifier.toString(mod); String constructorParameter = getConstructorParameter(c); System.out.println(" "+ConstructorModifier+" " + c.getName() + "("+constructorParameter+"){"); System.out.println(" }"); } } /** * 获取构造方法中的参数 * @param c * @return */ public static String getConstructorParameter(Constructor c){ String qxTemp = ""; String qx = ""; int con = 0; Class[] parameterTypeArr = c.getParameterTypes(); //获取构造方法中的参数 for(Class clas : parameterTypeArr){ qxTemp += clas.getTypeName() + " org"+con+","; con++; } int qxTempLength = qxTemp.length(); //去掉空参的构造方法 if(qxTempLength > 0){ qx = qxTemp.substring(0, qxTempLength-1); } return qx; } /** * 获取除构造方法外其他的方法的逻辑 * @param classS */ public static void getMethodContent(Class classS){ Method[] method = classS.getDeclaredMethods(); for(Method m : method){ int mod = m.getModifiers(); String methodModifier = Modifier.toString(mod); //获取方法返回值类型 Type type = m.getGenericReturnType(); String methodParameter = getMethodParameter(m); System.out.println(" "+methodModifier +" "+ type.getTypeName() +" " + m.getName() + "("+methodParameter+"){"); System.out.println(" }"); } } /** * 获取其他方法的参数 * @param m * @return */ public static String getMethodParameter(Method m){ String qxTemp = ""; String qx = ""; int con = 0; Class[] parameterTypeArr = m.getParameterTypes(); //获取构造方法中的参数 for(Class clas : parameterTypeArr){ qxTemp += clas.getTypeName()+" org"+con+","; con++; } int qxTempLength = qxTemp.length(); //去掉空参的构造方法 if(qxTempLength > 0){ qx = qxTemp.substring(0, qxTempLength-1); } return qx; } /** * 全局变量初始化值 * @param typeName * @param fi * @param classS * @return * @throws IllegalArgumentException * @throws IllegalAccessException * @throws InstantiationException */ public static String getValue(String typeName,Field fi,Class classS) throws IllegalArgumentException, IllegalAccessException, InstantiationException{ String value = ""; Object obj = classS.newInstance(); fi.setAccessible(true); String[] types = {"java.lang.Integer", "java.lang.Double", "java.lang.Float", "java.lang.Long", "java.lang.Short", "java.lang.Byte", "java.lang.Boolean", "java.lang.Character", "int","double","long","short","byte","boolean","char","float"}; for(String str : types) { if(fi.getType().getName().equals("java.lang.String")){ Object fiObj = fi.get(obj); //判断变量是否初始化 if(fiObj != null){ //String 类型参数需要用双引号扩上 value = "\""+fiObj.toString()+"\";"; }else{ value = null; } }else if(fi.getType().getName().equals(str)){ value = fi.get(obj).toString()+";"; } } return value; }