Java Read Properties Property file

Package com.newer;


Import Java.io.File;
Import Java.io.FileInputStream;
Import Java.net.URI;
Import java.net.URISyntaxException;
Import java.util.Properties;


/**
* Dynamically read properties File class
* @author RSun
* @Date 2012-11-14 03:18:17
*/
Public final class Readpropertiesfile {


/** the full name of the property file and reconfigure Pfile if needed **/
private static String PFILE = "Test.properties"; SRC underneath the file

The Property object variable for the/** property file **/
Private long m_lastmodifiedtime = 0;

/** the file object variable corresponding to the property file **/
Private File m_file = null;

The Property object variable for the/** property file **/
Private Properties m_props = null;


/** Unique Instance **/
private static Readpropertiesfile m_instance = new Readpropertiesfile ();




/** Private Constructor **/
Private Readpropertiesfile () {
try {
M_lastmodifiedtime = GetFile (). LastModified ();
if (M_lastmodifiedtime = = 0) {
System.err.println (PFILE + "file does not exist!");
}
M_props = new Properties ();
M_props.load (New FileInputStream (GetFile ()));


catch (URISyntaxException e) {
System.err.println (PFILE + "Incorrect file path");
E.printstacktrace ();
catch (Exception e) {
System.err.println (PFILE + "file read exception");
E.printstacktrace ();
}
}



/**
* Find classpath path to get files
* @return File Object
* @throws URISyntaxException
*/
Private File GetFile () throws URISyntaxException {
URI Fileuri = This.getclass (). getClassLoader (). GetResource (PFILE). Touri ();
M_file = new file (Fileuri);
return m_file;
}



/**
* Static Factory method
* @return Returns a single instance of Configurationread
*/
Public synchronized static Readpropertiesfile getinstance () {
return m_instance;
}



/**
* Read a specific property entry
* @param name of a property item
* @param defaultval Read failed default value
* @return
*/
public string Getconfigitem (string name, String defaultval) {
Long newtime = m_file.lastmodified ();
Check whether the property file has been modified
if (NewTime = = 0) {
Property file does not exist
if (M_lastmodifiedtime = = 0) {
System.err.println (PFILE + "file does not exist!");
} else {
System.err.println (PFILE + "file was deleted!!");
}
return defaultval;
else if (NewTime > M_lastmodifiedtime) {
M_props.clear ();
try {
M_props.load (New FileInputStream (GetFile ()));
catch (Exception e) {
System.err.println ("File re-read exception");
E.printstacktrace ();
}
}
M_lastmodifiedtime = NewTime;
String val = m_props.getproperty (name);
if (val = = null) {
return defaultval;
} else {
return Val;
}
}




/**
* Read a specific property entry
* @param the item name of the Name property item
* @return The value of the property entry (such an item exists), NULL (such an item does not exist)
*/
public string Getconfigitem (string name) {
Return Getconfigitem (Name, "");
}



/**
* Read a specific property entry
* @param name of a property item
* @return The value of the space after the Intercept
*/
public string Getconfigitemtrim (string name) {
Return Getconfigitem (Name, ""). Trim ();
}


Test
public static void Main (string[] args) {
System.out.println (Readpropertiesfile.getinstance (). Getconfigitemtrim ("AAA"));
System.out.println (Readpropertiesfile.getinstance (). Getconfigitemtrim ("BBB"));
System.out.println (Readpropertiesfile.getinstance (). Getconfigitem ("CCC", "Haha, you've been fooled.") "));
}

}