极客教程Java IntBuffer compareTo()方法
java.nio.IntBuffer 类的 compareTo() 方法是用来比较一个缓冲区和另一个缓冲区。两个int缓冲区通过比较它们的剩余元素序列进行比较，不考虑每个序列在其相应缓冲区中的起始位置。一对int元素的比较是通过调用Int.compare(int, int)进行的，除了-0和0被认为是相等的。本方法认为Int.NaN等于自己，并且大于所有其他的int值（包括Int.POSITIVE_INFINITY）。一个int缓冲区不能与任何其他类型的对象相提并论。
语法:
public int compareTo(IntBuffer that)
参数 ：该方法接受一个 intbuffer对象 作为参数，该缓冲区将与之进行比较。
返回值： 该方法在该缓冲区小于、等于或大于给定的缓冲区时返回一个 负整数、零或正整数 。下面的程序说明了 compareTo() 方法：
例子1： 当两个IntBuffer相等时。
// Java program to demonstrate
// compareTo() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the ib
int capacity1 = 3;
// Creating the IntBuffer
try {
// creating object of Intbuffer ib
// and allocating size capacity
IntBuffer ib = IntBuffer.allocate(capacity1);
// putting the value in ib
ib.put(9);
ib.put(7);
ib.put(4);
// rewind the Int buffer
ib.rewind();
// print the IntBuffer
System.out.println("IntBuffer ib: "
+ Arrays.toString(ib.array()));
// creating object of Intbuffer ib1
// and allocating size capacity
IntBuffer ib1 = IntBuffer.allocate(capacity1);
// putting the value in ib1
ib1.put(9);
ib1.put(7);
ib1.put(4);
// rewind the Int buffer
ib1.rewind();
// print the IntBuffer
System.out.println("IntBuffer ib1: "
+ Arrays.toString(ib1.array()));
// compare both buffer and store the value into integer
int i = ib.compareTo(ib1);
// if else condition
if (i == 0)
System.out.println("\nBoth buffer are lexicographically equal");
else if (i >= 0)
System.out.println("\nib is lexicographically greater than ib1");
else
System.out.println("\nib is lexicographically less than ib1");
}
catch (IllegalArgumentException e) {
System.out.println("Exception throws : " + e);
}
catch (ReadOnlyBufferException e) {
System.out.println("Exception throws : " + e);
}
}
}
输出
IntBuffer ib: [9, 7, 4]
IntBuffer ib1: [9, 7, 4]
Both buffer are lexicographically equal
例2： 当这个IntBuffer大于传递的IntBuffer时
// Java program to demonstrate
// compareTo() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the ib
int capacity1 = 3;
// Creating the IntBuffer
try {
// creating object of Intbuffer ib
// and allocating size capacity
IntBuffer ib = IntBuffer.allocate(capacity1);
// putting the value in ib
ib.put(9);
ib.put(7);
ib.put(4);
// rewind the Int buffer
ib.rewind();
// print the IntBuffer
System.out.println("IntBuffer ib: "
+ Arrays.toString(ib.array()));
// creating object of Intbuffer ib1
// and allocating size capacity
IntBuffer ib1 = IntBuffer.allocate(capacity1);
// putting the value in ib1
ib1.put(8);
ib1.put(7);
ib1.put(4);
// rewind the Int buffer
ib1.rewind();
// print the IntBuffer
System.out.println("IntBuffer ib1: "
+ Arrays.toString(ib1.array()));
// compare both buffer and store the value into integer
int i = ib.compareTo(ib1);
// if else condition
if (i == 0)
System.out.println("\nBoth buffer are lexicographically equal");
else if (i >= 0)
System.out.println("\nib is lexicographically greater than ib1");
else
System.out.println("\nib is lexicographically less than ib1");
}
catch (IllegalArgumentException e) {
System.out.println("Exception throws : " + e);
}
catch (ReadOnlyBufferException e) {
System.out.println("Exception throws : " + e);
}
}
}
输出
IntBuffer ib: [9, 7, 4]
IntBuffer ib1: [8, 7, 4]
ib is lexicographically greater than ib1
例3： 当这个IntBuffer小于传递的IntBuffer时。
// Java program to demonstrate
// compareTo() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the ib
int capacity1 = 3;
// Creating the IntBuffer
try {
// creating object of Intbuffer ib
// and allocating size capacity
IntBuffer ib = IntBuffer.allocate(capacity1);
// putting the value in ib
ib.put(8);
ib.put(7);
ib.put(4);
// rewind the Int buffer
ib.rewind();
// print the IntBuffer
System.out.println("IntBuffer ib: "
+ Arrays.toString(ib.array()));
// creating object of Intbuffer ib1
// and allocating size capacity
IntBuffer ib1 = IntBuffer.allocate(capacity1);
// putting the value in ib1
ib1.put(9);
ib1.put(7);
ib1.put(4);
// rewind the Int buffer
ib1.rewind();
// print the IntBuffer
System.out.println("IntBuffer ib1: "
+ Arrays.toString(ib1.array()));
// compare both buffer and store the value into integer
int i = ib.compareTo(ib1);
// if else condition
if (i == 0)
System.out.println("\nBoth buffer are lexicographically equal");
else if (i >= 0)
System.out.println("\nib is lexicographically greater than ib1");
else
System.out.println("\nib is lexicographically less than ib1");
}
catch (IllegalArgumentException e) {
System.out.println("Exception throws : " + e);
}
catch (ReadOnlyBufferException e) {
System.out.println("Exception throws : " + e);
}
}
}
输出
IntBuffer ib: [8, 7, 4]
IntBuffer ib1: [9, 7, 4]
ib is lexicographically less than ib1