Java read and write operations to properties configuration files

1.1. Read 1.1.1 to the properties profile. The file to read

configuration file Key and the value with a colon between [:] and equals sign [=] it's all possible. .

Test.properties

Name:\u5f20\u4e09 Password:\u5bc6\u7801 Age:

1.1.2. program code to read

Propertiestest.java

/** * Read config file * @throws ioexception * /@Test public Void Read () throws ioexception{ Properties Properties = new properties (); File File = new file ("Test.properties"); FileInputStream fis = new FileInputStream (file); Properties.load (FIS); set<object> KeySet = Properties.keyset (); for (Object object:keyset) { System.out.println (object.tostring () + ":" +properties.getproperty (object.tostring ())); } }

1.1.3. Results

Background Printing results

Age:22 Password: password Name: Zhang San

1.2. Write to the Propertiest configuration file 1.2.1. Code that writes the program

Propertiestest.java

/** * Write content to config file * @throws ioexception * /@Test public Void Write () throws IOException { Properties Properties = new properties (); String file = "Aa.properties"; FileOutputStream fos = new FileOutputStream (file); Properties.setproperty ("AA", "123"); Properties.setproperty ("BB", "456"); Properties.setproperty ("CC", "789"); Properties.setproperty ("name", "Zhang San"); Properties.store (FOS, "Save File"); Fos.close (); }

1.2.2. Results

Aa.propertiest

#\u4fdd\u5b58\u6587\u4ef6 #Sun Jan 14:06:25 CST 2015 Name=\u5f20\u4e09 Aa=123 bb=456 cc=789

1.3. Modify the properties configuration file 1.3.1. Pre-modified configuration file

Test.properties

Age=22 password= Password Name= Zhang San

1.3.2. Modifying a program's code

Propertiestest.java

/** * Changes to configuration file * @throws IOException * /@Test public Void Update () throws ioexception{ Properties Properties = new properties (); File File = new file ("Test.properties"); FileInputStream fis = new FileInputStream (file); FileOutputStream fos = new FileOutputStream (file); Properties.load (FIS); Properties.setproperty ("name", "John Doe"); Properties.setproperty ("Age", "222"); Properties.setproperty ("Age3", "222"); Properties.store (FOS, "update config file"); Fos.close (); Fis.close (); }

1.3.3. modified file contents

Test.properties

#\u66f4\u65b0\u914d\u7f6e\u6587\u4ef6 #Sun Jan 15:20:40 CST 2015 age=222 Name=\u674e\u56db password=\u5bc6\u7801 age3=222

1.4. Delete 1.4.1 for the properties profile. Delete the contents of the pre-configuration file

Test.properties

#\u66f4\u65b0\u914d\u7f6e\u6587\u4ef6 #Sun Jan 15:20:40 CST 2015 age=222 Name=\u674e\u56db password=\u5bc6\u7801 age3=222

1.4.2. Removing code from a program

Propertiestest.java

/** * Delete key in config file * @throws ioexception * */@Test public void Delete () throws ioexception{Pr Operties Properties = new properties (); File File = new file ("Test.properties"); FileInputStream fis = new FileInputStream (file); Properties.load (FIS); Must first use MAP to save all the content first, or delete, the original content has not map<string, string> map = new hashmap<string, string> (); set<object> KeySet = Properties.keyset (); System.out.println (Keyset.size ()); For (object Object:keyset) {string key = (string) Object; String value = (string) properties.get (key); System.out.println (key+ "=" +value); Map.put (key, value); }//Delete key Map.Remove ("Age3"); Properties.remove ("Age3"); For (java.util.map.entry<string, string> entry:map.entrySet ()) {Properties.setproperty (Entry.getkey (), E Ntry.getvalue ()); } fileoutputstream fos = new FileOutputStream (file); Properties.store (Fos, "delete key:age3 in config file"); Fos.close (); Fis.close (); }

1.4.3. Post-deletion configuration file contents

Test.properties

#\u5220\u9664\u914d\u7f6e\u6587\u4ef6\u4e2d\u7684key:age3 #Sun Jan 15:23:58 CST 2015 age=222 Name=\u674e\u56db password=\u5bc6\u7801

1.5. Complete program code

Propertietest.java

Import Java.io.file;import java.io.fileinputstream;import java.io.fileoutputstream;import java.io.IOException; Import Java.util.hashmap;import java.util.map;import java.util.properties;import java.util.Set; Import Org.junit.Test; public class Propertiestest {public static void main (string[] args) {}/** * Delete key in configuration file * @throws IO Exception * */@Test public void Delete () throws ioexception{Properties Properties = New Properties () ; File File = new file ("Test.properties"); FileInputStream fis = new FileInputStream (file); Properties.load (FIS); Must first use MAP to save all the content first, or delete, the original content has not map<string, string> map = new hashmap<string, string> (); set<object> KeySet = Properties.keyset (); System.out.println (Keyset.size ()); For (object Object:keyset) {string key = (string) Object; String value = (string) properties.get (key); System.out.println (key+ "=" +value); Map.put (key, value); }//Delete key Map.Remove ("Age3"); Properties.remove ("Age3"); For (java.util.map.entry<string, string> entry:map.entrySet ()) {Properties.setproperty (Entry.getkey (), E Ntry.getvalue ()); } fileoutputstream fos = new FileOutputStream (file); Properties.store (Fos, "delete key:age3 in config file"); Fos.close (); Fis.close (); }/** * Changes to configuration file * @throws IOException */@Test public void Update () throws ioexception{ Properties Properties = new properties (); File File = new file ("Test.properties"); FileInputStream fis = new FileInputStream (file); Properties.load (FIS); Must first use MAP to save all the content first, or an update, the original content has not map<string, string> Map = new hashmap<string, string> (); set<object> KeySet = Properties.keyset (); System.out.println (Keyset.size ()); For (object Object:keyset) {string key = (string) Object; String value = (string) properties.get (key); System.out.println (key+ "=" +value); Map.put (key, value); } map.put ("Name", "John Doe"); Map.put ("Age", "222"); Map.put ("Age3", "222"); For (java.util.map.entry<string, string> entry:map.entrySet ()) {Properties.setproperty (Entry.getkey (), E Ntry.getvalue ()); } fileoutputstream fos = new FileOutputStream (file); Properties.store (FOS, "update config file"); Fos.close (); Fis.close (); /** * Write content to config file * @throws IOException */@Test public void Write () throws IOException { Properties Properties = new properties (); String file = "Aa.properties"; FileOutputStream fos = new FileOutputStream (file); Properties.setproperty ("AA", "123"); Properties.setproperty ("BB", "456"); Properties.setproperty ("CC", "789"); Properties.setproperty ("name", "Zhang San"); Properties.store (FOS, "Save File"); Fos.close (); }/** * Read config file * @throws IOException */@Test public void Read () throws ioexception{Prop Erties Properties = new properties (); File File = new file ("Test.properties"); FileInputStream fis = new FileInputStream (file); Properties.load (FIS); set<object> KeySet = Properties.keyset (); for (Object object:keyset) {System.out.println (object.tostring () + "=" +properties.getproperty (object.tostring () )); } } }

Java read and write operations to properties configuration files