public class EncryptConfig { private Boolean enable; private String key; private String iv; private String salt; } 根据上述类写出可以通过build方法构造实例的代码

以下是可以通过build方法构造EncryptConfig实例的代码：

public class EncryptConfigBuilder {
    private Boolean enable;
    private String key;
    private String iv;
    private String salt;

    public EncryptConfigBuilder() {}

    public EncryptConfigBuilder withEnable(Boolean enable) {
        this.enable = enable;
        return this;
    }

    public EncryptConfigBuilder withKey(String key) {
        this.key = key;
        return this;
    }

    public EncryptConfigBuilder withIv(String iv) {
        this.iv = iv;
        return this;
    }

    public EncryptConfigBuilder withSalt(String salt) {
        this.salt = salt;
        return this;
    }

    public EncryptConfig build() {
        EncryptConfig config = new EncryptConfig();
        config.enable = enable;
        config.key = key;
        config.iv = iv;
        config.salt = salt;
        return config;
    }
}

使用示例：

EncryptConfig config = new EncryptConfigBuilder()
    .withEnable(true)
    .withKey("my key")
    .withIv("my iv")
    .withSalt("my salt")
    .build();