Java中的CharBuffer equals()方法
Java.nio.CharBuffer类的equals()方法用于检查给定缓冲区是否等于另一个对象。
两个 char 缓冲区相等当且仅当，
- 它们具有相同的元素类型，
- 它们具有相同数量的剩余元素，并且
- 剩余元素的两个序列，独立于它们的起始位置考虑，是逐点的
平等的。
此方法认为两个 char 元素 'a' 和 'b' 相等 if ('a' == 'b') || (Char.isNaN(a) && Char.isNaN(b))。与 Char.equals(Object) 不同，值 -0 和 +0 被认为是相等的。
char 缓冲区不等于任何其他类型的对象。
句法：
public boolean equals(Object ob)参数：此方法将ob （与此缓冲区进行比较的对象）作为参数。
返回值：当且仅当此缓冲区等于给定对象时，此方法返回true 。
以下是说明equals()方法的示例：
示例 1：
// Java program to demonstrate
// equals() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the CharBuffer 1
int capacity1 = 10;
// Declaring the capacity of the CharBuffer 2
int capacity2 = 10;
// Creating the CharBuffer
try {
// creating object of Charbuffer 1
// and allocating size capacity
CharBuffer cb1 = CharBuffer.allocate(capacity1);
// creating object of Charbuffer 2
// and allocating size capacity
CharBuffer cb2 = CharBuffer.allocate(capacity2);
// putting the value in Charbuffer 1
cb1.put('a');
cb1.put(2, 'b');
cb1.rewind();
// putting the value in Charbuffer 2
cb2.put('a');
cb2.put(2, 'b');
cb2.rewind();
// print the CharBuffer 1
System.out.println(" CharBuffer 1: "
+ Arrays.toString(cb1.array()));
// print the CharBuffer 2
System.out.println(" CharBuffer 2: "
+ Arrays.toString(cb2.array()));
// checking the equality of both CharBuffer
boolean cbb = cb1.equals(cb2);
// checking if else condition
if (cbb)
System.out.println("Both are equal");
else
System.out.println("Both are not equal");
}
catch (IllegalArgumentException e) {
System.out.println("IllegalArgumentException catched");
}
catch (ReadOnlyBufferException e) {
System.out.println("ReadOnlyBufferException catched");
}
}
}
输出：
CharBuffer 1: [a,, b,,,,,,, ]
CharBuffer 2: [a,, b,,,,,,, ]
Both are equal
示例 2：
// Java program to demonstrate
// equals() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the CharBuffer 1
int capacity1 = 10;
// Declaring the capacity of the CharBuffer 2
int capacity2 = 5;
// Creating the CharBuffer
try {
// creating object of Charbuffer 1
// and allocating size capacity
CharBuffer cb1 = CharBuffer.allocate(capacity1);
// creating object of Charbuffer 2
// and allocating size capacity
CharBuffer cb2 = CharBuffer.allocate(capacity2);
// putting the value in Charbuffer 1
cb1.put('a');
cb1.put(2, 'b');
cb1.rewind();
// putting the value in Charbuffer 2
cb2.put('a');
cb2.put(2, 'b');
cb2.rewind();
// print the CharBuffer 1
System.out.println(" CharBuffer 1: "
+ Arrays.toString(cb1.array()));
// print the CharBuffer 2
System.out.println(" CharBuffer 2: "
+ Arrays.toString(cb2.array()));
// checking the equality of both CharBuffer
boolean cbb = cb1.equals(cb2);
// checking if else condition
if (cbb)
System.out.println("Both are equal");
else
System.out.println("Both are not equal");
}
catch (IllegalArgumentException e) {
System.out.println("IllegalArgumentException catched");
}
catch (ReadOnlyBufferException e) {
System.out.println("ReadOnlyBufferException catched");
}
}
}
输出：
CharBuffer 1: [a,, b,,,,,,, ]
CharBuffer 2: [a,, b,, ]
Both are not equal
示例 3：
// Java program to demonstrate
// equals() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the CharBuffer 1
int capacity1 = 10;
// Declaring the capacity of the CharBuffer 2
int capacity2 = 10;
// Creating the CharBuffer
try {
// creating object of Charbuffer 1
// and allocating size capacity
CharBuffer cb1 = CharBuffer.allocate(capacity1);
// creating object of Charbuffer 2
// and allocating size capacity
CharBuffer cb2 = CharBuffer.allocate(capacity2);
// putting the value in Charbuffer 1
cb1.put('a');
cb1.put(2, 'b');
cb1.rewind();
// putting the value in Charbuffer 2
cb2.put('a');
cb2.put(2, 'b');
cb2.put(3, 'c');
cb2.put(4, 'd');
cb2.rewind();
// print the CharBuffer 1
System.out.println(" CharBuffer 1: "
+ Arrays.toString(cb1.array()));
// print the CharBuffer 2
System.out.println(" CharBuffer 2: "
+ Arrays.toString(cb2.array()));
// checking the equality of both CharBuffer
boolean cbb = cb1.equals(cb2);
// checking if else condition
if (cbb)
System.out.println("Both are equal");
else
System.out.println("Both are not equal");
}
catch (IllegalArgumentException e) {
System.out.println("IllegalArgumentException catched");
}
catch (ReadOnlyBufferException e) {
System.out.println("ReadOnlyBufferException catched");
}
}
}
输出：
CharBuffer 1: [a,, b,,,,,,, ]
CharBuffer 2: [a,, b, c, d,,,,, ]
Both are not equal