自己弄的一个幼稚作品，不懂哪里错误百出...
public class Testcup
{
String d;
int w;
static String Test1(String d)
{
if (String d = "塑料的")
{
String r = "Yes";
return r;
}
else if (String d = "玻璃的")
{
String r = "No";
return r;
}
else
{
String r = "Er";
return r;
}
}
static String Test2(int w)
{
if (w <10)
{
Srting o = "Yes";
return o;
}
else
{
String o = "Heavy";
return o;
}
}
public static void main(String[] args)
{
Testcup e = new Testcup();
e.d = "塑料的";
e.w = 9;
if (Test1(e.d)==Test2(e.w))
{
System.out.println("This one is required");
}
else
{
System.out.println("I'm sorry , this one is not required") ;
}
}
}

[解决办法]
else if (String d = "玻璃的") 改为 else if (d .equals( "玻璃的"))
[解决办法]

Java code

public class Testcup {    String d;    int w;    static String Test1(String d) {        if (d == "塑料的") {// 判用“==”符，(String d ="塑料的")是一值句，if句只接受true或false或者表式            String r = "Yes";            return r;        } else if (d == "玻璃的") {// 同上            String r = "No";            return r;        } else {            String r = "Er";            return r;        }    }    static String Test2(int w) {        if (w < 10) {            String o = "Yes";// StringSrting了            return o;        } else {            String o = "Heavy";            return o;        }    }    public static void main(String[] args) {        Testcup e = new Testcup();        e.d = "塑料的";        e.w = 9;        if (Test1(e.d) == Test2(e.w)) {            System.out.println("This one is required");        } else {            System.out.println("I'm sorry , this one is not required");        }    }}
[解决办法]
探讨


Java code

public class Testcup {
    String d;
    int w;

    static String Test1(String d) {
        if (d == "塑料的") {// 判用“==”符，(String d ="塑料的")是一值句，if句只接受true或false或者表式
            S……

[解决办法]
首先条件判断的（）里只能填关系判断符：< > ==(在java中2个=是相等的意思，而1个=是赋值的意思，把右边的值赋给左边的)，前面的关系判断符只能对基本数据类型进行判断，而对于String这种特殊类型的也就是引用数据类型应该用"equals"例如：
if (d.equals("玻璃"))
这是判断d的值是否是玻璃


[解决办法]
这是个小程序，还不能称之为作品
------解决方案-------------------- 
 
Java code
public class Arrag {    String d;    int w;    static String Test1(String d) {        if (d.equals("塑料的")) {            String r = "Yes";            return r;        } else if (d.equals("玻璃的")) {            String r = "No";            return r;        } else {            String r = "Er";            return r;        }    }    static String Test2(int w) {        if (w < 10) {            String o = "Yes";            return o;        } else {            String o = "Heavy";            return o;        }    }    public static void main(String[] args) {        Arrag e = new Arrag();        e.d = "塑料的";        e.w = 9;        if (Test1(e.d).equals(Test2(e.w))) {            System.out.println("This one is required");        } else {            System.out.println("I'm sorry , this one is not required");        }    }}