首先,这个问题将是关于相同代码的两个问题。另外,请原谅我对这门语言的无知,我在过去的两周才学会Java,这是我第一个主要项目的一部分。
考虑以下代码:
<>之前公共类TESTCODE {
public static ArrayList<String> bytePossibalitiyGenerator(int bits, String current) throws Exception {
ArrayList<String> binaries = new ArrayList<>();
if (bits%8 != 0) {
int crash = bits%8;
throw new Exception("The bit count that you have entered is not divisable by 8:" + "n" + "There is a remainder of: " + Integer.toString(crash));
} else {
if (current.length() == bits) {
binaries.add(current);
return binaries;
}
// pad a 0 and 1 in front of current;
binaries.addAll(bytePossibalitiyGenerator(bits, "0" + current));
binaries.addAll(bytePossibalitiyGenerator(bits, "1" + current));
System.out.println(binaries.toString());
}
return binaries;
}
//The method below is supposed to format out the whitespace between binary strings and arrange the
//data in such a way that each possible outcome is on a new line.
//TODO Add a parser for the size of the byte ex. if the binary string is comprised of all of the possible
//TODO outcomes for 1 byte than every 8 instead of appending a space, append a new line.
public static String binarySequencer(String input) {
StringBuffer toReturn = new StringBuffer();
//This StringBuilder is a safety precaution to ensure that if the algorithm is to be
//run again, the value of each previously read and appended string position is nullified
//so that it is not re-appended to the StringBuffer
StringBuilder inputSB = new StringBuilder(input);
//Setting the booleans for which type of string the input was (The raw binary array itself, or the array converted into a string)
boolean rawBinaryArrayOutput = Pattern.compile("^[0-1,\s]+$").matcher(input).find();
boolean stringBinary = Pattern.compile("^[0-1\t]+$").matcher(input).find();
//This boolean is to check whether the loop has previously passed over 1 byte for sequencing
boolean hasPassedAByte = false;
//Safety if statements, because who doesn't love Java Exceptions and stack traces...
if (rawBinaryArrayOutput == false && stringBinary == false || rawBinaryArrayOutput == true && stringBinary == true) {
System.out.println(rawBinaryArrayOutput);
System.out.println(stringBinary);
//TODO Find a way to print the stack trace...
throw new InputMismatchException();
} else {
int runLength = 0;
for (int i = 0; i < inputSB.length(); i++) {
int j = 0;
if (stringBinary == true && rawBinaryArrayOutput == false) {
if (runLength == 8 && (inputSB.charAt(j += i) == 0 || inputSB.charAt(j += 1) == 1)) {
toReturn.append(Character.toString(' '));
runLength = 0;
hasPassedAByte = true;
} else {
if (hasPassedAByte = true && runLength == 8 && (inputSB.charAt(j) != 0 || inputSB.charAt(j) != 1)) {
toReturn.append("n");
runLength = 0;
hasPassedAByte = false;
}
while (i + 1 < inputSB.length() && (inputSB.charAt(i) == 0 || inputSB.charAt(i) == 1) && runLength != 8) {
runLength++;
toReturn.append(inputSB.charAt(i));
inputSB.insert(i, null);
i++;
}
}
} else {
if (rawBinaryArrayOutput == true && stringBinary == false) {
//Insert code for formatting the raw binary array output
System.out.println("You haven't added this code yet :p");
}
}
}
}
return toReturn.toString();
}
public static void main(String[] args) throws Exception {
String toBeSequenced = "";
for (String s : bytePossibalitiyGenerator(16, "")) {
toBeSequenced += s + "t";
}
System.out.println(binarySequencer(toBeSequenced));}}
之前现在是问题:
1:对于boolean rawBinaryArrayOutput
,我使用java.util.regex.Pattern
类的compile
方法来搜索正在输入的字符串中的{0-1 , \s}
字符,如果它找到其中的任何一个,它将rawBinaryArrayOutput
设置为true。是否有一种方法,使它只设置rawBinaryArrayOutput
为真,如果发现所有这些值中的至少一个?
2:在binarySequencer
方法中,我有一个StringBuilder inputSB
自动取String input
的值,这样我就可以修改StringBuilder
中的值。在第75行,我试图将位置i
的值设置为null
,以便如果while循环以某种方式在同一位置上运行两次,它不会向StringBuilder toReturn
追加任何内容,但是Eclipse在The method (int, Object) is ambiguous for type StringBuilder
行上给了我一个编译错误。这是什么意思,我该如何解决?
3:我在binarySequencer
方法的开头有一个if语句,检查是否rawBinaryArrayOutput == false && stringBinary == false || rawBinaryArrayOutput == true && stringBinary == true
,如果它们是,那么它将throw new InputMismatchException();
。如果可能的话,我该如何让它也打印出堆栈跟踪呢?
-
对于
rawBinaryArrayOutput
,您可以尝试使用regex:^([01](,s)?)+$
将接受具有
0
或1
序列的字符串(一个或多个char)由可选的,s
部分分隔。但是对于比特输入,可能最好是:^(?:(?:[01]{8})+(?:,s)?)+$
只接受
0
或8个字符序列中的一个或多个1
。 The method (int, Object) is ambiguous for type StringBuilder
据我所知,意味着StringBuilder类有两个类似的方法,在这种情况下,它是:insert(int, String)
和insert(int, char[])
,以及编译器没有知道要调用哪个变量,因为作为第二个变量使用null
, null引用可以转换为任何类类型的表达式。试一试:
例如inputSB.insert(i, (char[]) null);
。那么你调用哪个方法就很明显了,即使它是
我不会使用InputMismatchException(),最好抛出另一个自定义异常。使用正确的正则表达式,将没有双真匹配的选项,而使用双假匹配,您可以只打印有用的信息。
?:
部分用于不按regex分组。