Java输入输出

Java从文件读取输入

// Read matrix from file Input.txtBufferedReader br = null;try {br = new BufferedReader(new FileReader("Input.txt"));} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}String str = "";try {int j = 0;while ((str = br.readLine()) != null) {String[] strarray = str.split(" ");for (int i = 0; i < strarray.length; i++) {a[j][i] = b[j][i] = Integer.parseInt(strarray[i]);// System.out.print(strarray[i] + " ");}j++;// System.out.println();}} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}

java从控制台读取输入

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));String input = null;try {input = br.readLine();} catch (Exception e) {e.printStackTrace();}

java读取配置文件

package nk;// 从Config文件中读取所需内容// 2012年3月21日import java.io.IOException;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.InputStream;import java.io.OutputStream;import java.util.Properties;public class ParseProperties {public static String getValue(String filePathName, String key)throws IOException {Properties prop = new Properties();InputStream in = null;try {in = ParseProperties.class.getResourceAsStream(filePathName);// in = new FileInputStream(filePathName);prop.load(in);String value = prop.getProperty(key);return value;} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();return null;} finally {if (in != null)in.close();}}public static void setProperties(String filePathName, String key,String value) throws IOException {Properties prop = new Properties();InputStream in = null;OutputStream out = null;try {in = ParseProperties.class.getResourceAsStream(filePathName); // .class 文件下找// in=new FileInputStream(filePathName); // 绝对路径prop.load(in);out = new FileOutputStream(filePathName);prop.setProperty(key, value);prop.store(out, key);out.flush();out.close();} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} finally {if (in != null)in.close();if (out != null)out.close();}}public static void main(String[] args) {// TODO Auto-generated method stubString filePathName = "DomU.properties";String Dom1ID;try {Dom1ID = ParseProperties.getValue(filePathName,"Dom1ID");System.out.println(Dom1ID);System.out.println("user.dir :"+System.getProperty("user.dir"));} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}System.setSecurityManager(null);}}