Java中的Collections.replaceAll()方法和List.replaceAll()方法
Collections接口的replaceAll()方法接受一个List对象，这是两个键入参数，分别代表旧值和新值，并用列表中的新值替换旧值。
示例
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class ReplaceAllExample {
public static void main(String args[]) {
List<String> list = new ArrayList<String>();
list.add("Java");
list.add("Java Script");
list.add("HBase");
list.add("CoffeeScript");
list.add("TypeScript");
System.out.println("Contents of list: "+list);
Collections.replaceAll(list, "Java", "JAVA");
System.out.print("Contents of list after replace operation: \n"+list);
}
}输出结果
Contents of list: [Java, Java Script, HBase, CoffeeScript, TypeScript] Contents of list after replace operation: [JAVA, Java Script, HBase, CoffeeScript, TypeScript]
replaceAll()List接口的方法接受UnaryOperator的对象，该对象表示特定操作对当前列表的所有元素执行指定的操作，并将现有值替换为结果值。
示例
import java.util.ArrayList;
import java.util.function.UnaryOperator;
class Op implements UnaryOperator<String> {
public String apply(String str) {
return str.toUpperCase();
}
}
public class Test {
public static void main(String[] args) throws CloneNotSupportedException {
ArrayList<String> list = new ArrayList<>();
list.add("Java");
list.add("JavaScript");
list.add("CoffeeScript");
list.add("HBase");
list.add("OpenNLP");
System.out.println("Contents of the list: "+list);
list.replaceAll(new Op());
System.out.println("Contents of the list after replace operation: \n"+list);
}
}输出结果
Contents of the list: [Java, JavaScript, CoffeeScript, HBase, OpenNLP] Contents of the list after replace operation: [JAVA, JAVASCRIPT, COFFEESCRIPT, HBASE, OPENNLP]