Java中的集合checkedSortedMap()方法和示例
Java.util.Collections类的checkedSortedMap()方法用于返回指定排序映射的动态类型安全视图。
如果指定的映射是可序列化的,则返回的映射将是可序列化的。
由于 null 被认为是任何引用类型的值,因此返回的映射允许在支持映射时插入空键或值。
句法:
public static SortedMap
checkedSortedMap(SortedMap m, Class keyType, Class valueType)
参数:此方法将以下参数作为参数
- m –要为其返回动态类型安全视图的映射
- keyType –允许 m 持有的密钥类型
- valueType –允许 m 持有的值的类型
返回值:此方法返回指定映射的动态类型安全视图。
以下是说明checkedSortedMap()方法的示例
示例 1:
Java
// Java program to demonstrate
// checkedSortedMap() method
// for type
import java.util.*;
public class GFG1 {
public static void main(String[] argv)
throws Exception
{
try {
// creating object of SortedMap
SortedMap
smap = new TreeMap();
// Adding element to smap
smap.put("Ram", "Gopal");
smap.put("Karan", "Arjun");
smap.put("Karn", "Veer");
// printing the sorted map
System.out.println("Sorted map:\n"
+ smap);
// create typesafe view of the specified map
SortedMap
tsmap = Collections
.checkedSortedMap(smap,
Output:
{Karan=39, Karn=40, Ram=20}
String.class,
String.class);
// printing the typesafe view of specified sorted map
System.out.println("Typesafe view of sorted map:\n"
+ tsmap);
}
catch (IllegalArgumentException e) {
System.out.println("Exception thrown : " + e);
}
}
}
Java
// Java program to demonstrate
// checkedSortedMap() method
// for type
import java.util.*;
public class GFG1 {
public static void main(String[] argv) throws Exception
{
try {
// creating object of SortedMap
SortedMap smap = new TreeMap();
// Adding element to smap
smap.put("Ram", 20);
smap.put("Karan", 39);
smap.put("Karn", 40);
// printing the sorted map
System.out.println("Sorted map:\n"
+ smap);
// create typesafe view of the specified map
SortedMap
tsmap = Collections
.checkedSortedMap(smap,
String.class,
Integer.class);
// printing the typesafe view of specified sorted map
System.out.println("Typesafe view of sorted map:\n"
+ tsmap);
}
catch (IllegalArgumentException e) {
System.out.println("Exception thrown : " + e);
}
}
}
输出:
Sorted map:
{Karan=Arjun, Karn=Veer, Ram=Gopal}
Typesafe view of sorted map:
{Karan=Arjun, Karn=Veer, Ram=Gopal}
示例 2:
Java
// Java program to demonstrate
// checkedSortedMap() method
// for type
import java.util.*;
public class GFG1 {
public static void main(String[] argv) throws Exception
{
try {
// creating object of SortedMap
SortedMap smap = new TreeMap();
// Adding element to smap
smap.put("Ram", 20);
smap.put("Karan", 39);
smap.put("Karn", 40);
// printing the sorted map
System.out.println("Sorted map:\n"
+ smap);
// create typesafe view of the specified map
SortedMap
tsmap = Collections
.checkedSortedMap(smap,
String.class,
Integer.class);
// printing the typesafe view of specified sorted map
System.out.println("Typesafe view of sorted map:\n"
+ tsmap);
}
catch (IllegalArgumentException e) {
System.out.println("Exception thrown : " + e);
}
}
}
输出:
Sorted map:
{Karan=39, Karn=40, Ram=20}
Typesafe view of sorted map:
{Karan=39, Karn=40, Ram=20}