Java 无法在方法中创建实例的其他引用

我正在用Eclipse制作一个计算器程序作为练习。我犯了很多错误。我想做的是更改this和dec这两个引用的名称，以便在方法的后面使代码更加清晰。有什么问题

public Decimals plus(Decimals dec) {
    //let's get the length of the 2 numbers
    int this_len=this.getLength(), dec_len=dec.getLength();
    int longest_len;
    //to simplify the code the two numbers are called long or short
    Decimals short; //shortest   <-- Syntax error on token 'short', ++ expected / Decimals cannot be resolved to a variable
    Decimals long; //longest   <-- Syntax error on token 'long', ++ expected / Decimals cannot be resolved to a variable
    if (this_len >= dec_len){
        short = dec;   // <-- Syntax error on token "=", delete this token / Duplicate local variable dec
        long = this;  // <-- Syntax error on token "long", invalid Expression
        longest_len = this_len; 
    }
    else {
        short = this; // <-- Syntax error on token "short", VariableDeclaratorId expected after this token
        long = dec; //  <-- Syntax error on token "long", invalid Expression
        longest_len = dec_len;
    }

---

短和长是关键词。不能将它们用作变量名。最短和最长都可以。

short和long是基本类型。不能将原语用作变量名称短和长是Java中的关键字。它们是语言保留的，您不能将它们用作变量名。谢谢，我从未想过这一点