java面试题：读取文件中含有ERROR的行

 

java面试题：读取文件中含有ERROR的行

 

public class LogsUtils {

	private static final String LOG_PATH = "foshan.log";

	public String readError() {

		StringBuilder build = new StringBuilder();

		InputStream is = null;
		InputStreamReader isReader = null;
		BufferedReader bufReader = null;

		try {
			// 读取相对路径下的文件
			is = Thread.currentThread().getContextClassLoader()
					.getResourceAsStream(LOG_PATH);

			isReader = new InputStreamReader(is);

			bufReader = new BufferedReader(isReader);

			String line = null;

			while ((line=bufReader.readLine()) != null) {

				if (line.contains("ERROR") || line.contains("error")) {
					build.append(line).append("\n");
				}
			}

		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			closeIO(bufReader, isReader, is);
		}

		return build.toString();
	}

	public void closeIO(BufferedReader bufReader, InputStreamReader isReader,
			InputStream is) {

		if (null != bufReader) {
			try {
				bufReader.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			bufReader = null;
		}

		if (null != isReader) {
			try {
				isReader.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			isReader = null;
		}

		if (null != is) {
			try {
				is.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			is = null;
		}
	}

	public static void main(String[] args) {
		String error = new LogsUtils().readError();
		System.out.println(error);
	}
}