java.util.jar.JarInputStream#available ( )源码实例Demo

public static Map<String, byte[]> extractClasses(JarInputStream jarReader, NameStyle nameStyle) throws IOException {

        Map<String, byte[]> classMap = new HashMap<>();
        byte[] tempReadingBuffer = new byte[MAX_CLASS_BYTES];

        JarEntry entry;
        while (null != (entry = jarReader.getNextJarEntry())) {
            String name = entry.getName();

            if (name.endsWith(".class")
                    && !name.equals("package-info.class")
                    && !name.equals("module-info.class")) {

                String internalClassName = name.replaceAll(".class$", "");
                if (nameStyle.equals(NameStyle.DOT_NAME)) {
                    internalClassName = Utilities.internalNameToFulllyQualifiedName(internalClassName);
                }
                int readSize = jarReader.readNBytes(tempReadingBuffer, 0, tempReadingBuffer.length);

                if (0 != jarReader.available()) {
                    throw new RuntimeException("Class file too big: " + name);
                }

                byte[] classBytes = new byte[readSize];
                System.arraycopy(tempReadingBuffer, 0, classBytes, 0, readSize);
                classMap.put(internalClassName, classBytes);
            }
        }
        return classMap;
    }
 

private void replaceManifest(InputStream is, OutputStream os, Manifest manifest) throws IOException {
    JarInputStream in = new JarInputStream(is);
    try {
        JarOutputStream out = new JarOutputStream(os, manifest);
        try {
            JarEntry entry = null;
            byte[] temp = new byte[32768];
            while ((entry = in.getNextJarEntry()) != null) {
                String name = entry.getName();
                if (name.equalsIgnoreCase("META-INF/MANIFEST.MF")) { // NOI18N
                    continue;
                }
                out.putNextEntry(entry);
                while (in.available() != 0) {
                    int read = in.read(temp);
                    if (read != -1) {
                        out.write(temp, 0, read);
                    }
                }
                out.closeEntry();
            }
        } finally {
            out.close();
        }
    } finally {
        in.close();
    }
}
 

private boolean unzipJarAlt(String pathJar, String pathDir) {
	try {
		FileInputStream fileStream = new FileInputStream(File.separator + pathJar);
		JarInputStream jarStream = new JarInputStream(fileStream);
		JarEntry entry = jarStream.getNextJarEntry();
		
		while (entry != null) {
			File fileEntry = new File(File.separator + pathDir + File.separator + entry.getName());
			
			if (entry.isDirectory()) {
				fileEntry.mkdirs();
			}
			else {
				FileOutputStream os = new FileOutputStream(fileEntry);
				
				while (jarStream.available() > 0) {
					os.write(jarStream.read());
				}
				
				os.close();
			}
			entry = jarStream.getNextJarEntry();
		}
		
		jarStream.close();
		return true;
	} 
	catch (IOException e) {
		e.printStackTrace();
	}
	
	return false;
}
 

@Override
public Map<String, byte[]> getClassData() {
	byte[] jarData = getFileData();

	try {
		ByteArrayInputStream bis = new ByteArrayInputStream(jarData);
		JarInputStream jis = new JarInputStream(bis);
		JarEntry entry = jis.getNextJarEntry();
		Map<String, byte[]> classData = new HashMap<String, byte[]>();
		while (entry != null) {
			String name = entry.getName();
			if (name.endsWith(".class")) {
				ByteArrayOutputStream bos = new ByteArrayOutputStream();
				while (jis.available() > 0) {
					bos.write(jis.read());
				}
				classData.put(DominoUtils.filePathToJavaBinaryName(name, "/"), bos.toByteArray());
			}

			entry = jis.getNextJarEntry();
		}
		jis.close();

		return classData;
	} catch (IOException ioe) {
		DominoUtils.handleException(ioe);
		return null;
	}
}
 

@Override
public Map<String, byte[]> getClassData() {
	// For this one, we'll need the note in the database
	if (classData == null) {
		classData = new TreeMap<String, byte[]>();
		try {
			byte[] jarData = getFileDataRaw("%%object%%.jar");

			InputStream objInputStream = new ByteArrayInputStream(jarData);
			JarInputStream jis = new JarInputStream(objInputStream);
			JarEntry entry = jis.getNextJarEntry();
			while (entry != null) {
				String name = entry.getName();
				if (name.endsWith(".class")) { //TODO our classloader should support resources also!
					ByteArrayOutputStream bos = new ByteArrayOutputStream();
					while (jis.available() > 0) {
						bos.write(jis.read());
					}
					classData.put(DominoUtils.filePathToJavaBinaryName(name, "/"), bos.toByteArray());
				}

				entry = jis.getNextJarEntry();
			}
			jis.close();
			objInputStream.close();

		} catch (Exception e) {
			e.printStackTrace();
		}

	}
	return classData;

}