总结Java程序运行时常见的异常

总结了几个JAVA中常见的RuntimeException

1、ClassCastException：类型强制转换异常

示例：

package com.darkmi.basic;

public class Test {

public static void main(String[] args) {

testParse("aaa");

}

public static void testParse(Object str){

Integer i = (Integer)str;

}

}

异常信息如下：

Exception in thread "main" java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer

at com.darkmi.basic.Test.testParse(Test.java:10)

at com.darkmi.basic.Test.main(Test.java:6)

2、ArithmeticExecption：算术异常类：

示例：

package com.darkmi.basic;

public class Test {

public static void main(String[] args) {

int a = 10 / 0;

System.out.println(a);

}

}

异常信息如下：

Exception in thread "main" java.lang.ArithmeticException: / by zero

at com.darkmi.basic.Test.main(Test.java:6)

三、ArrayIndexOutOfBoundsException：数组下标越界异常

示例：

package com.darkmi.basic;

public class Test {

public static void main(String[] args) {

int[] a = {0,1,2,3};

System.out.println(a[4]);

}

}

异常信息如下：

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 4

at com.darkmi.basic.Test.main(Test.java:7)

四、NullPointerException：空指针异常类

示例：

package com.darkmi.basic;

public class Test {

public static void main(String[] args) {

System.out.println(toUpper(null));

}

public static String toUpper(String str){

return str.toUpperCase();

}

}

异常信息如下：

Exception in thread "main" java.lang.NullPointerException

at com.darkmi.basic.Test.toUpper(Test.java:11)

at com.darkmi.basic.Test.main(Test.java:6)

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