Java Utililty Methods InputStream Read

String getFileContent(InputStream in)
Helper method to obtain the content of a source file.

String content = "";
BufferedReader inReader = new BufferedReader(new InputStreamReader(in));
while (inReader.ready()) {
 String line = inReader.readLine();
 content = content + line + "\n";
return content;

String getFileContent(InputStream inputStream)
get File Content

byte[] bytes = new byte[28];
try {
 inputStream.read(bytes, 0, 28);
} catch (IOException e) {
 throw new RuntimeException("read file content error!");
return bytesToHexString(bytes);

String getFileContent(InputStream is)
There is a much cleaner implementation of doing this, but good enough since it is only used for testing

BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = null;
StringBuffer buff = new StringBuffer();
while ((line = br.readLine()) != null) {
 buff.append(line + "\n");
return buff.toString();

String getFileContent(InputStream stream)
get File Content

InputStreamReader reader = new InputStreamReader(stream);
char[] arr = new char[8 * 1024]; 
StringBuilder buf = new StringBuilder();
int numChars;
while ((numChars = reader.read(arr, 0, arr.length)) > 0) {
 buf.append(arr, 0, numChars);
return buf.toString().intern(); 
...

InputStream getInputStream(Class clazz)
get Input Stream

InputStream is = null;
is = clazz.getResourceAsStream(DEFAULT_STRATEGIES_PATH);
if (is == null) {
 throw new FileNotFoundException(
 DEFAULT_STRATEGIES_PATH + " cannot be opened because it does not exist");
return is;

InputStream getInputStream(Class ownerClass, String subName, String extension)
Opens an InputStream for a class-associated resource.

String localName;
if (subName == null) {
 localName = ownerClass.getSimpleName() + '.' + extension;
} else {
 localName = ownerClass.getSimpleName() + '_' + subName + '.' + extension;
return ownerClass.getResourceAsStream(localName);

InputStream getInputstream(File compressedFile)
Gets the compressed input stream for an image

try {
 return new GZIPInputStream(new FileInputStream(compressedFile));
catch (Exception e) {
 e.printStackTrace();
return null;

InputStream getInputStream(JarFile file, ZipEntry entry)
get Input Stream

try {
 return file.getInputStream(entry);
} catch (IOException e) {
 throw new IllegalStateException(e);

InputStream getInputStream(Object caller, String name)
Return an appropriate InputStream for the specified test file (which must be inside our current package.

return (caller.getClass().getResourceAsStream("/org/apache/commons/digester3/plugins/" + name));

InputStream getInputStreamAsResource(Class clazz, String fileName)
get Input Stream As Resource

InputStream stream = clazz.getResourceAsStream(fileName);
return stream;