异常处理相关基础操作~~~
（1）异常处理方法
（2）多个异常处理
（3）Finally的用法
（4）使用catch处理异常
（5）多线程处理异常
（6）获取异常的堆栈信息
（7）重载方法处理异常
（8）链试异常
（9）自定义异常
1 public class ExceptionControl { 2 // 异常处理方法 3 private static void ExceptionFunction() { 4 try { 5 throw new Exception("MY Exception"); 6 } catch (Exception e) { 7 System.err.println("Caught Exception"); 8 System.err.println("getMessage():" + e.getMessage()); 9 System.err.println("getLocalizedMessage():" + e.getLocalizedMessage()); 10 System.err.println("toString():" + e); 11 System.err.println("printStackTrace():"); 12 e.printStackTrace(); 13 } 14 } 15 16 17 // 多个异常处理 18 static class Demo { 19 int div(int a, int b) throws ArithmeticException, ArrayIndexOutOfBoundsException { 20 int[] arr = new int[a]; 21 System.out.println(arr[4]); //制造的第一处异常 22 return a / b; //制造的第二处异常 23 } 24 } 25 26 private static void ManyCatch() { 27 Demo d = new Demo(); 28 try { 29 int x = d.div(4, 0); 30 //int x = d.div(5,0); 31 //int x = d.div(4,1); 32 System.out.println("x=" + x); 33 } catch (ArithmeticException e) { 34 System.out.println(e.toString()); 35 } catch (ArrayIndexOutOfBoundsException e) { 36 System.out.println(e.toString()); 37 } catch (Exception e) { 38 System.out.println(e.toString()); 39 } 40 System.out.println("Over"); 41 } 42 43 // Finally的用法 44 private static void FinallyUse() { 45 new ExceptionDemo2().doTheWork(); 46 } 47 48 static class ExceptionDemo2 { 49 public static void doTheWork() { 50 Object o = null; 51 for (int i = 0; i < 5; i++) { 52 try { 53 o = makeObj(i); 54 } catch (IllegalArgumentException e) { 55 System.err.println 56 ("Error: (" + e.getMessage() + ")."); 57 return; 58 } finally { 59 System.err.println("都已执行完毕"); 60 if (o == null) 61 System.exit(0); 62 } 63 System.out.println(o); 64 } 65 } 66 67 private static Object makeObj(int type) 68 throws IllegalArgumentException { 69 if (type == 1) 70 throw new IllegalArgumentException 71 ("不是指定的类型： " + type); 72 return new Object(); 73 } 74 } 75 76 77 // 使用catch处理异常 78 private static void UseCatchDealException() { 79 int array[] = {20, 20, 40}; 80 int num1 = 15, num2 = 10; 81 int result = 5; 82 try { 83 result = num1 / num2; 84 System.out.println("结果为 " + result); 85 for (int i = 5; i >= 0; i--) { 86 System.out.println("数组的元素值为 " + array[i]); 87 } 88 } catch (Exception e) { 89 System.out.println("触发异常 : " + e); 90 } 91 } 92 93 94 // 多线程处理异常 95 private static void ThreadingException() { 96 MyThread t = new MyThread(); 97 t.start(); 98 try { 99 Thread.sleep(1000); 100 } catch (Exception x) { 101 System.out.println("Caught it" + x); 102 } 103 System.out.println("Exiting main"); 104 } 105 106 static class MyThread extends Thread { 107 public void run() { 108 System.out.println("Throwing in " + "MyThread"); 109 throw new RuntimeException(); 110 } 111 } 112 113 114 // 获取异常的堆栈信息 115 private static void GetExceptionStackInfo() { 116 int array[] = {20, 20, 40}; 117 int num1 = 15, num2 = 10; 118 int result = 10; 119 try { 120 result = num1 / num2; 121 System.out.println("The result is" + result); 122 for (int i = 5; i <= 0; i--) { 123 System.out.println("The value of array is" + array[i]); 124 } 125 } catch (Exception e) { 126 e.printStackTrace(); 127 } 128 } 129 130 131 // 重载方法异常处理 132 private static void LoadFunctionException() { 133 MainDemo mn = new MainDemo(); 134 try { 135 System.out.println(mn.method(10, 20.0)); 136 System.out.println(mn.method(10.0, 20)); 137 System.out.println(mn.method(10.0, 20.0)); 138 System.out.println(mn.method(10)); 139 } catch (Exception ex) { 140 System.out.println("exception occoure: " + ex); 141 } 142 } 143 144 static class MainDemo { 145 double method(int i) throws Exception { 146 return i / 0; 147 } 148 149 static boolean method(boolean b) { 150 return !b; 151 } 152 153 static double method(int x, double y) throws Exception { 154 return x + y; 155 } 156 157 static double method(double x, double y) { 158 return x + y - 3; 159 } 160 } 161 162 163 // 链试异常 164 private static void DealLinkException() throws Exception { 165 int n = 20, result = 0; 166 try { 167 result = n / 0; 168 System.out.println("结果为" + result); 169 } catch (ArithmeticException ex) { 170 System.out.println("发算术异常: " + ex); 171 try { 172 throw new NumberFormatException(); 173 } catch (NumberFormatException ex1) { 174 System.out.println("手动抛出链试异常 : " + ex1); 175 } 176 } 177 } 178 179 180 // 自定义异常 181 private static void DelDiyException() { 182 try { 183 new Input().method(); 184 } catch (WrongInputException wie) { 185 System.out.println(wie.getMessage()); 186 } 187 } 188 189 190 static class WrongInputException extends Exception { 191 WrongInputException(String s) { 192 super(s); 193 } 194 } 195 196 static class Input { 197 void method() throws WrongInputException { 198 throw new WrongInputException("Wrong input"); 199 } 200 } 201 202 public static void main(String[] args) throws Exception { 203 ExceptionFunction(); 204 ManyCatch(); 205 FinallyUse(); 206 UseCatchDealException(); 207 ThreadingException(); 208 GetExceptionStackInfo(); 209 LoadFunctionException(); 210 DealLinkException(); 211 DelDiyException(); 212 } 213 214 }