Java Notes-11

using the following methods of the  Collections class:

public static Collection synchronizedCollection(Collection c)
public static Set synchronizedSet(Set s)
public static List synchronizedList(List list)
public static Map synchronizedMap(Map m)
public static SortedSet synchronizedSortedSet(SortedSet s)
public static SortedMap synchronizedSortedMap(SortedMap m)

List list = new ArrayList();
List syncList = Collections.synchronizedList(list);

synchronized(syncList) {
Iterator iterator = syncList.iterator();
// do stuff with the iterator here
}

-You can use the  Collections class to create read-only versions of any collection

public static Collection unmodifiableCollection(Collection c)
public static Set unmodifiableSet(Set s)
public static List unmodifiableList(List list)
public static Map unmodifiableMap(Map m)
public static SortedSet unmodifiableSortedSet(SortedSet s)
public static SortedMap unmodifiableSortedMap(SortedMap m)

-Any string values can be stored as key/value pairs in a  Properties table. However, the convention is to use a dot-separated naming hierarchy to group property names into
logical structures. 

Properties props = new Properties();
props.setProperty("myApp.xsize", "52");
props.setProperty("myApp.ysize", "79");

String xsize = props.getProperty( "myApp.xsize" );

props.save( System.out, "Application Parameters" );

FileInputStream fin;
...
Properties props = new Properties()
props.load( fin );

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"
>
<properties>
<comment>My Properties</comment>
<entry key="myApp.ysize">79</entry>
<entry key="myApp.xsize">52</entry>
</properties>

 Next:The Preference API

Java Notes-11

原文：http://blog.csdn.net/yu444/article/details/45439201