使用通用表达式语言(CEL)在列表中查找值的示例

import com.google.api.expr.v1alpha1.CheckedExpr;
import com.google.api.expr.v1alpha1.Expr;
import com.google.api.expr.v1alpha1.ExprValue;
import com.google.api.expr.v1alpha1.Value;
import com.google.api.expr.v1alpha1.Value.KindCase;
import com.google.api.expr.v1alpha1.Value.Type;

import java.util.ArrayList;
import java.util.List;

public class CELExample {
    public static void main(String[] args) {
        // 创建一个包含对象的列表
        List<Person> personList = new ArrayList<>();
        personList.add(new Person("Alice", 25));
        personList.add(new Person("Bob", 30));
        personList.add(new Person("Charlie", 35));

        // 定义要查找的属性值
        String targetName = "Bob";

        // 创建CEL表达式
        Expr expr = Expr.newBuilder()
                .setId(1)
                .setSourceInfo(Expr.SourceInfo.newBuilder().build())
                .setCallExpr(Expr.Call.newBuilder()
                        .setFunction("ListContains")
                        .addArgs(Expr.newBuilder()
                                .setId(2)
                                .setConstExpr(Expr.Constant.newBuilder()
                                        .setValue(Value.newBuilder()
                                                .setStringExpr(targetName)
                                                .setType(Type.STRING)
                                                .build())
                                        .build())
                                .build())
                        .addArgs(Expr.newBuilder()
                                .setId(3)
                                .setIdentExpr(Expr.Ident.newBuilder()
                                        .setName("name")
                                        .build())
                                .build())
                        .build())
                .build();

        // 遍历列表并使用CEL表达式进行匹配
        for (Person person : personList) {
            // 创建CEL表达式的输入值
            ExprValue input = ExprValue.newBuilder()
                    .setId(4)
                    .setValue(Value.newBuilder()
                            .setObjectValue(ExprValue.ObjectValue.newBuilder()
                                    .putFields("name", Value.newBuilder()
                                            .setStringExpr(person.getName())
                                            .setType(Type.STRING)
                                            .build())
                                    .build())
                            .build())
                    .build();

            // 使用CEL表达式求值
            CheckedExpr checkedExpr = CEL.evaluate(expr, input);

            // 检查CEL表达式的结果
            if (checkedExpr.getResult().getBoolValue()) {
                System.out.println("找到匹配的对象：" + person.getName());
            }
        }
    }

    static class Person {
        private String name;
        private int age;

        public Person(String name, int age) {
            this.name = name;
            this.age = age;
        }

        public String getName() {
            return name;
        }

        public int getAge() {
            return age;
        }
    }
}