Java中的 MessageFormat parse() 方法示例：Set – 1

Java.text.MessageFormat类的parse()方法用于从索引的开头解析字符串对象。
句法：

public Object[] parse(String source)
               throws ParseException

参数：此方法将字符串源作为将要进行解析的参数。
返回值：此方法返回对象数组作为输出。
异常：如果无法解析指定字符串的开头，则此方法抛出ParseException 。
以下是说明parse()方法的示例：
示例 1：

Java

// Java program to demonstrate
// parse() method
 
import java.text.*;
import java.util.*;
import java.io.*;
 
public class GFG {
    public static void main(String[] argv)
    {
        try {
            // creating and initializing  MessageFormat
            MessageFormat mf
                = new MessageFormat("{0, number, #}, {2, number, #.#}, {1, number, #.##}");
            ;
 
            // creating and initializing String source
            String str = "10.456, 20.325, 30.444";
 
            // parsing the string
            // according to MessageFormat
            // using parse() method
            Object[] hash = mf.parse(str);
 
            // display the result
            System.out.println("Parsed value are :");
            for (int i = 0; i < hash.length; i++)
                System.out.println(hash[i]);
        }
        catch (ParseException e) {
            System.out.println("\nString is Null");
            System.out.println("Exception thrown : " + e);
        }
    }
}

输出：

Parsed value are :
10.456
30.444
20.325

示例 2：

Java

// Java program to demonstrate
// parse() method
 
import java.text.*;
import java.util.*;
import java.io.*;
 
public class GFG {
    public static void main(String[] argv)
    {
        try {
            // creating and initializing  MessageFormat
            MessageFormat mf
                = new MessageFormat("{0, date}, {2, time}, {1, number}");
 
            // creating and initializing String source
            String str = "10, 20, 30";
 
            // parsing the string
            // according to MessageFormat
            // using parse() method
            Object[] hash = mf.parse(str);
 
            // display the result
            System.out.println("Parsed value are :");
            for (int i = 0; i < hash.length; i++)
                System.out.println(hash[i]);
        }
        catch (ParseException e) {
            System.out.println("String is Null");
            System.out.println("Exception thrown : " + e);
        }
    }
}

输出：

String is Null
Exception thrown : java.text.ParseException: MessageFormat parse error!

参考： https://docs.oracle.com/javase/9/docs/api/ Java/text/MessageFormat.html#parse-java.lang.String-