原因是没有初始构造
package org.example;
public class InitializeBlockClass {
public int field=100;
{
field=200;
}
public InitializeBlockClass(int field) {
this.field = field;
}
public InitializeBlockClass() {
}
public static void main(String[] args) {
InitializeBlockClass obj=new InitializeBlockClass();
System.out.println(obj.field);
obj=new InitializeBlockClass(300);
System.out.println(obj.field);
}
}
package org.example;
public class InitializeBlockClass {
{
field=200;
}
public int field=100;
public InitializeBlockClass(int field) {
this.field = field;
}
public InitializeBlockClass() {
}
public static void main(String[] args) {
InitializeBlockClass obj=new InitializeBlockClass();
System.out.println(obj.field);
obj=new InitializeBlockClass(300);
System.out.println(obj.field);
}
}
