Java读取Properties文件的六种方法

使用J2SE API读取Properties文件的六种方法

1。使用java.util.Properties类的load()方法
示例： InputStream in = lnew BufferedInputStream(new FileInputStream(name));
Properties p = new Properties();
p.load(in);

2。使用java.util.ResourceBundle类的getBundle()方法
示例： ResourceBundle rb = ResourceBundle.getBundle(name, Locale.getDefault());

3。使用java.util.PropertyResourceBundle类的构造函数
示例： InputStream in = new BufferedInputStream(new FileInputStream(name));
ResourceBundle rb = new PropertyResourceBundle(in);

4。使用class变量的getResourceAsStream()方法
示例： InputStream in = JProperties.class.getResourceAsStream(name);
Properties p = new Properties();
p.load(in);

5。使用class.getClassLoader()所得到的java.lang.ClassLoader的getResourceAsStream()方法
示例： InputStream in = JProperties.class.getClassLoader().getResourceAsStream(name);
Properties p = new Properties();
p.load(in);

6。使用java.lang.ClassLoader类的getSystemResourceAsStream()静态方法
示例： InputStream in = ClassLoader.getSystemResourceAsStream(name);
Properties p = new Properties();
p.load(in);

补充

Servlet中可以使用javax.servlet.ServletContext的getResourceAsStream()方法
示例：InputStream in = context.getResourceAsStream(path);
Properties p = new Properties();
p.load(in);

完整的示例，可以参考附件文件
 
JProperties.java文件

//import javax.servlet.ServletContext;  import java.util.*;  import java.io.InputStream;  import java.io.IOException;  import java.io.BufferedInputStream;  import java.io.FileInputStream;      public class JProperties {    public final static int BY_PROPERTIES = 1;  public final static int BY_RESOURCEBUNDLE = 2;  public final static int BY_PROPERTYRESOURCEBUNDLE = 3;  public final static int BY_CLASS = 4;  public final static int BY_CLASSLOADER = 5;  public final static int BY_SYSTEM_CLASSLOADER = 6;    public final static Properties loadProperties(final String name, final int type) throws IOException {  Properties p = new Properties();  InputStream in = null;  if (type == BY_PROPERTIES) {  in = new BufferedInputStream(new FileInputStream(name));  assert (in != null);  p.load(in);  } else if (type == BY_RESOURCEBUNDLE) {  ResourceBundle rb = ResourceBundle.getBundle(name, Locale.getDefault());  assert (rb != null);  p = new ResourceBundleAdapter(rb);  } else if (type == BY_PROPERTYRESOURCEBUNDLE) {  in = new BufferedInputStream(new FileInputStream(name));  assert (in != null);  ResourceBundle rb = new PropertyResourceBundle(in);  p = new ResourceBundleAdapter(rb);  } else if (type == BY_CLASS) {  assert (JProperties.class.equals(new JProperties().getClass()));  in = JProperties.class.getResourceAsStream(name);  assert (in != null);  p.load(in);  // return new JProperties().getClass().getResourceAsStream(name);  } else if (type == BY_CLASSLOADER) {  assert (JProperties.class.getClassLoader().equals(new JProperties().getClass().getClassLoader()));  in = JProperties.class.getClassLoader().getResourceAsStream(name);  assert (in != null);  p.load(in);  // return new JProperties().getClass().getClassLoader().getResourceAsStream(name);  } else if (type == BY_SYSTEM_CLASSLOADER) {  in = ClassLoader.getSystemResourceAsStream(name);  assert (in != null);  p.load(in);  }    if (in != null) {  in.close();  }  return p;    }    // ---------------------------------------------- servlet used      // ---------------------------------------------- support class      public static class ResourceBundleAdapter extends Properties {  public ResourceBundleAdapter(ResourceBundle rb) {  assert (rb instanceof java.util.PropertyResourceBundle);  this.rb = rb;  java.util.Enumeration e = rb.getKeys();  while (e.hasMoreElements()) {  Object o = e.nextElement();  this.put(o, rb.getObject((String) o));  }  }    private ResourceBundle rb = null;    public ResourceBundle getBundle(String baseName) {  return ResourceBundle.getBundle(baseName);  }    public ResourceBundle getBundle(String baseName, Locale locale) {  return ResourceBundle.getBundle(baseName, locale);  }    public ResourceBundle getBundle(String baseName, Locale locale, ClassLoader loader) {  return ResourceBundle.getBundle(baseName, locale, loader);  }    public Enumeration getKeys() {  return rb.getKeys();  }    public Locale getLocale() {  return rb.getLocale();  }    public Object getObject(String key) {  return rb.getObject(key);  }    public String getString(String key) {  return rb.getString(key);  }    public String[] getStringArray(String key) {  return rb.getStringArray(key);  }    protected Object handleGetObject(String key) {  return ((PropertyResourceBundle) rb).handleGetObject(key);  }    }    }    JPropertiesTest.java文件      package com.kindani.test;    import junit.framework.*;  import com.kindani.JProperties;    //import javax.servlet.ServletContext;  import java.util.Properties;    public class JPropertiesTest extends TestCase {  JProperties jProperties;  String key = "helloworld.title";  String value = "Hello World!";    public void testLoadProperties() throws Exception {  String name = null;  Properties p = new Properties();    name = "C:\\IDEAP\\Properties4Methods\\src\\com\\kindani\\test\\LocalStrings.properties";  p = JProperties.loadProperties(name, JProperties.BY_PROPERTIES);  assertEquals(value, p.getProperty(key));    name = "com.kindani.test.LocalStrings";  p = JProperties.loadProperties(name,JProperties.BY_RESOURCEBUNDLE);  assertEquals(value, p.getProperty(key));  assertEquals(value,((JProperties.ResourceBundleAdapter)p).getString(key));    name = "C:\\IDEAP\\Properties4Methods\\src\\com\\kindani\\test\\LocalStrings.properties";  p = JProperties.loadProperties(name, JProperties.BY_PROPERTYRESOURCEBUNDLE);  assertEquals(value, p.getProperty(key));  assertEquals(value,((JProperties.ResourceBundleAdapter)p).getString(key));    name = "\\com\\kindani\\test\\LocalStrings.properties";  p = JProperties.loadProperties(name, JProperties.BY_SYSTEM_CLASSLOADER);  assertEquals(value, p.getProperty(key));    name = "\\com\\kindani\\test\\LocalStrings.properties";  p = JProperties.loadProperties(name, JProperties.BY_CLASSLOADER);  assertEquals(value, p.getProperty(key));    name = "test\\LocalStrings.properties";  p = JProperties.loadProperties(name, JProperties.BY_CLASS);  assertEquals(value, p.getProperty(key));  }      }    properties文件与JPropertiesTest.java文件相同的目录下  LocalStrings.properties文件  # $Id: LocalStrings.properties,v 1.1 2000/08/17 00:57:52 horwat Exp $    # Default localized resources for example servlets  # This locale is en_US    helloworld.title=Hello World!    requestinfo.title=Request Information Example  requestinfo.label.method=Method:  requestinfo.label.requesturi=Request URI:  requestinfo.label.protocol=Protocol:  requestinfo.label.pathinfo=Path Info:  requestinfo.label.remoteaddr=Remote Address:    requestheader.title=Request Header Example    requestparams.title=Request Parameters Example  requestparams.params-in-req=Parameters in this request:  requestparams.no-params=No Parameters, Please enter some  requestparams.firstname=First Name:  requestparams.lastname=Last Name:    cookies.title=Cookies Example  cookies.cookies=Your browser is sending the following cookies:  cookies.no-cookies=Your browser isn't sending any cookies  cookies.make-cookie=Create a cookie to send to your browser  cookies.name=Name:  cookies.value=Value:  cookies.set=You just sent the following cookie to your browser:    sessions.title=Sessions Example  sessions.id=Session ID:  sessions.created=Created:  sessions.lastaccessed=Last Accessed:  sessions.data=The following data is in your session:  sessions.adddata=Add data to your session  sessions.dataname=Name of Session Attribute:  sessions.datavalue=Value of Session Attribute:    -----------------------------------------------------------------------------------------------------------------------------------------------    Java对properties配置文件的操作      package com.yorsun;    import java.io.File;  import java.io.FileInputStream;  import java.io.FileNotFoundException;  import java.io.FileOutputStream;  import java.io.IOException;  import java.util.Properties;    import javax.servlet.ServletContext;  import javax.servlet.http.HttpServlet;      public class PropertiesUnit {  private String filename;    private Properties p;    private FileInputStream in;    private FileOutputStream out;    public PropertiesUnit(String filename) {  this.filename = filename;  File file = new File(filename);  try {  in = new FileInputStream(file);  p = new Properties();  p.load(in);  in.close();  } catch (FileNotFoundException e) {  // TODO Auto-generated catch block  System.err.println("配置文件config.properties找不到！");  e.printStackTrace();  } catch (IOException e) {  // TODO Auto-generated catch block  System.err.println("读取配置文件config.properties错误！");  e.printStackTrace();  }  }    public static String getConfigFile(HttpServlet hs) {  return getConfigFile(hs, "config.properties");  }      private static String getConfigFile(HttpServlet hs, String configFileName) {  String configFile = "";  ServletContext sc = hs.getServletContext();  configFile = sc.getRealPath("/" + configFileName);  if (configFile == null || configFile.equals("")) {  configFile = "/" + configFileName;  }  // TODO Auto-generated method stub  return configFile;  }    public void list() {  p.list(System.out);  }    public String getValue(String itemName) {  return p.getProperty(itemName);  }    public String getValue(String itemName, String defaultValue) {  return p.getProperty(itemName, defaultValue);  }    public void setValue(String itemName, String value) {  p.setProperty(itemName, value);  }    public void saveFile(String filename, String description) throws Exception {  try {  File f = new File(filename);  out = new FileOutputStream(f);  p.store(out, description);  out.close();  } catch (IOException ex) {  throw new Exception("无法保存指定的配置文件:" + filename);  }  }    public void saveFile(String filename) throws Exception{  saveFile(filename,"");  }    public void saveFile() throws Exception{  if(filename.length()==0)  throw new Exception("需指定保存的配置文件名");  saveFile(filename);  }    public void deleteValue(String value){  p.remove(value);  }    public static void main(String args[]){  String file="/eclipse/workspace/NewsTest/WEB-INF/config.properties";  // String file="D:\\eclipse\\workspace\\NewsTest\\WEB-INF\\config.properties";  PropertiesUnit pu=new PropertiesUnit(file);  pu.list();  }    }    ---------------------------------------------------------------------------------------------------------------------------------    import java.io.BufferedInputStream;  import java.io.File;  import java.io.FileInputStream;  import java.io.FileNotFoundException;  import java.io.IOException;  import java.io.InputStream;  import java.util.Properties;    public class ReadPropertiesFile ...{    public void readPropertiesFile(String fileName) throws FileNotFoundException ...{  String str = "";  Properties prop = new Properties();    InputStream stream = null;    //读取这个类在同一包中的properties文件  //stream = getClass().getClassLoader().getResourceAsStream(fileName);  System.out.println("path:" + getClass().getResource(fileName));      //读取SRC下的的properties文件  String path = getClass().getResource("/").getPath();  stream = new BufferedInputStream(new FileInputStream(new File(path+fileName)));    try ...{  prop.load(stream);  str = prop.getProperty("localname");  System.out.println("localname:" + str);  System.out.println("properties:" + prop);  stream.close();    } catch (IOException e) ...{  // TODO Auto-generated catch block  e.printStackTrace();  }  }      public static void main(String[] args) throws FileNotFoundException ...{  // TODO Auto-generated method stub  new ReadPropertiesFile().readPropertiesFile("config.properties");    }    }    --------------------------------------------------------------------------------------------------------------------------------------    //=================sprin配置文件================================  <bean  id="userService"  class="com.thtf.ezone.ezesb.jmx.admin.service.impl.UserServiceImpl">  <property  name="filePath"  value="config/userInfo.properties" />  </bean>    //=================java文件================================    package com.thtf.ezone.ezesb.jmx.admin.service.impl;    import java.io.FileInputStream;  import java.io.IOException;  import java.util.Properties;    public class UserServiceImpl implements UserService {    String filePath = null;    public void setFilePath(String filePath) {  this.filePath = filePath;  }    public static void main(String dd[])throws Exception{    Properties p = new Properties();  FileInputStream ferr=new FileInputStream((getClass().getClassLoader()  .getResource("") + filePath).toString().substring(6));// 用subString(6)去掉：file:/try{  p.load(ferr);  ferr.close();  Set s = p.keySet();  Iterator it = s.iterator();  while(it.hasNext()){  String id = (String)it.next();  String value = p.getProperty(id);  System.out.println(id+":="+value);  }  }catch(Exception e){  e.printStackTrace();  }  }  }

#----------------------------------
# sql server 2000数据厍连接信息
#----------------------------------
dp.sd.DataBaseTyp=mssql
DataBaseHost=127.0.0.1:1433
DataBase=formpro
UserName=sa
PassWord=01
#----------------------------------
# mysql 数据厍连接信息
#----------------------------------
#DataBaseHost=127.0.0.1:3306
#DataBaseTyp=mysql
#DataBase=snow
#UserName=root
#PassWord=01
//==========================运行结果=======================

PassWord:=01
DataBaseHost:=127.0.0.1:1433
DataBase:=formpro
dp.sd.DataBaseTyp:=mssql
UserName:=sa