线程“main”中的异常java.lang.Error：未解析的变量
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Exception in thread "main" java.lang.Error: unresolved variable
提问by user3289740
Exception in thread "main" java.lang.Error: Why can't my parameter variable be resolved to a variable?
线程“main”中的异常java.lang.Error：为什么我的参数变量不能解析为变量？
I'm trying to create a simple program that creates two objects of the people class, give them names and make the first object ("lisa") be-friend the second object ("mark") and finally display/print out lisa's friend on screen.
我正在尝试创建一个简单的程序来创建 people 类的两个对象，给它们命名并使第一个对象（“lisa”）成为第二个对象（“mark”）的朋友，最后显示/打印出 lisa 的朋友在屏幕上。
But Eclipse displays the following error:
但是 Eclipse 显示以下错误：
Exception in thread "main" java.lang.Error: Unresolved compilation problems: lisa cannot be resolved to a variable mark cannot be resolved to a variable lisa cannot be resolved to a variable Syntax error, insert ";" to complete Statement The method friend() is undefined for the type People at People.main(People.java:22)
线程“main”中的异常java.lang.Error：未解决的编译问题：lisa无法解析为变量标记无法解析为变量lisa无法解析为变量语法错误，插入“;” 完成 Statement 方法friend() 在People.main(People.java:22) 中未定义为People 类型
As you can tell, I'm very new to Java, so I cannot understand what the error means and how I can fix it. Your help is greatly appreciated!
如您所知，我对 Java 很陌生，所以我无法理解错误的含义以及如何修复它。非常感谢您的帮助！
Here is my People class:
这是我的 People 课程：
public class People {
公共课人{
//Constructor
public void name(String name) {
this.name = name;
}
// Instance variables
public String name;
public String friend;
// Instance method
public void addFriend(String name){
name = Object1.friend();
}
}
Here is my main method:
这是我的主要方法：
public static void main(String[] args) {
公共静态无效主（字符串 [] args）{
People Object1 = new People();
Object1.name(lisa);
People Object2 = new People();
Object2.name(mark);
Object1.addFriend(lisa);
System.out.println(Object1.friend());
}
}
}
采纳答案by Meno Hochschild
Instead of
代替
People Object1 = new People();
Object1.name(lisa);
you should write:
你应该写：
People people = new People();
people.name("lisa");
Note first the quotation marks around "lisa". Without these quotation marks Java will interprete it as variable name and not as String (as required by signature of name()-method in class People. And it is a common convention in Java to write variable names like "Object1" in small letters - for code readability. Here as information the guidelines from Oracle.
首先注意“lisa”周围的引号。如果没有这些引号，Java 会将其解释为变量名而不是字符串（如 People 类中 name() 方法的签名所要求的那样。Java 中的常见约定是用小写字母编写“Object1”等变量名 -为了代码可读性。这里作为信息来自 Oracle 的指导方针。
