字符數組大小？用於將HTMl文件保存爲字符串的Stringbuffer

Question

我正在讀取HTML文件並將其保存爲字符串。我想讀取長度（int len = con.getcontentlength()）並將char charArray=new char(len)，但getContentLength的結果始終爲-1。 所以我修復charArray但如果我把 char[] charArray=new char[1]或 char[] charArray=new char[512]或 char[] charArray=new char[1024]

它始終工作。

我不明白爲什麼。從new char[1];

public static void main(String[] args) throws Exception 
{ 
    String name="AAAA";  
    URL url = new URL("http:..."); 
    URLConnection con = url.openConnection(); 

    InputStream is = con.getInputStream(); 
    InputStreamReader isr = new InputStreamReader(is); 

    int numCharsRead; 
    char[] charArray = new char[1]; 
    StringBuffer sb = new StringBuffer(); 
    while ((numCharsRead = isr.read(charArray)) > 0) 
     sb.append(charArray, 0, numCharsRead); 
    String htmlString = sb.toString(); 

Answer 1

更改爲new char[isr.available()];

Answer 2

InputStreamReader isr = new InputStreamReader(is); 
    int c = 0; 
    while((c = isr.read()) != -1) { 
     char character = (char) c; 

     System.out.println(character); 

    }