try/catch中finally的执行时间
前言
由于总是搞不清楚try/catch中的一个执行顺序，返回结果。所以总结一下
1.finally没有return 时，可以看出finally确实在return之前执行了
public static void main(String[] args) {
int aa = test1();
System.out.println(aa);
}
public static int test1(){
try{
System.out.println("try");
return 0;
}catch(Exception e){
System.out.println("catch");
return 1;
}finally {
System.out.println("finally");
}
}
//结果
//try
//finally
//0
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2. finally有return 时，会覆盖其他语句中的return
public static void main(String[] args) {
int aa = test1();
System.out.println(aa);
}
public static int test1(){
try{
System.out.println("try");
return 0;
}catch(Exception e){
System.out.println("catch");
return 1;
}finally {
System.out.println("finally");
return 2;
}
}
//结果
//try
//finally
//2
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3.finally中对基本数据类型没有影响
public static int test1(){
int result = 6;
try{
System.out.println("try");
return result;
}catch(Exception e){
System.out.println("catch");
return 1;
}finally {
System.out.println("finally");
result = 3;
}
}
//结果try
//finally
//6
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4.finally中对引用型数据有影响
public static StringBuffer test1(){
StringBuffer str = new StringBuffer("I");
try{
System.out.println("try");
return str;
}catch(Exception e){
System.out.println("catch");
return null;
}finally {
System.out.println("finally");
str.append("am");
}
}
//结果try
//finally
// I am
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5.当try/catch外面有异常，finally不执行
public static int test2(){
int a = 5/0;
try{
System.out.println("try");
return a;
}catch(Exception e){
System.out.println("catch");
return 2;
}finally {
System.out.println("finally");
}
}
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Exception in thread "main" java.lang.ArithmeticException: / by zero
at com.jxl.face.Controller.EnumTest.test2(EnumTest.java:29)
at com.jxl.face.Controller.EnumTest.main(EnumTest.java:19)
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6.异常在try/catch里面，finally无return
public static int test2(){
try{
int a = 5/0;
System.out.println("try");
return a;
}catch(Exception e){
System.out.println("catch");
return 2;
}finally {
System.out.println("finally");
}
}
//catch
//finally
//2
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7.异常在try/catch里面，finally有return
public static int test2(){
try{
int a = 5/0;
System.out.println("try");
return a;
}catch(Exception e){
System.out.println("catch");
return 2;
}finally {
System.out.println("finally");
return 3；
}
}
//catch
//finally
//3