在builder.create()上崩溃

MyObject obj = new MyObject.Builder()
    .setParam1(value1)
    .setParam2(value2)
    .build(); // 确保所有必要的 set 方法都被调用

public class MyObject {
    private int param1;
    private String param2;

    private MyObject(Builder builder) {
        this.param1 = builder.param1;
        this.param2 = builder.param2;
    }

    public static class Builder {
        private int param1;
        private String param2;

        public Builder setParam1(int param1) {
            this.param1 = param1;
            return this;
        }

        public Builder setParam2(String param2) {
            this.param2 = param2;
            return this;
        }

        public MyObject build() {
            if (param1 < 0 || param2 == null) {
                throw new IllegalArgumentException("Invalid parameters");
            }
            return new MyObject(this);
        }
    }
}

public class ThreadSafeBuilder {
    private final Object lock = new Object();
    private int param1;
    private String param2;

    public ThreadSafeBuilder setParam1(int param1) {
        synchronized (lock) {
            this.param1 = param1;
        }
        return this;
    }

    public ThreadSafeBuilder setParam2(String param2) {
        synchronized (lock) {
            this.param2 = param2;
        }
        return this;
    }

    public MyObject build() {
        synchronized (lock) {
            if (param1 < 0 || param2 == null) {
                throw new IllegalArgumentException("Invalid parameters");
            }
            return new MyObject(this);
        }
    }
}