Java 存储与类关联的键的最佳实践

将类中使用的一组键值对存储在单独的接口中是更好的做法还是将其存储在strings.xml中更好

e、 g:

public interface PreferenceKeys {
    static final String PREF1 = "pref1";
    static final String PREF2 = "pref2";
}

然后在我的代码中作为PreferenceKeys.PREF1访问它

vs

在string.xml中存储为名称-值对：

<string name="PREF1">pref1</string>
<string name="PREF2">pref2</string>

---

我想和大家分享一下我在preferences存储方面所做的工作，我使用了android的内置功能，名为。为了便于访问，我在

SharedReferences

周围创建了一个名为

UserModel

的包装器，其代码如下：

package tv.gsgw.android.garusuta.model;

import id.flwi.util.ActivityUtil;
import tv.gsgw.android.garusuta.constant.DataConstant;
import android.content.Context;

public class UserModel implements DataConstant {
    Context _context;

    private String authKey = "";
    private String email = "";
    private String password = "";
    private String birthdate = "";
    private String prefacture = "";
    private String bloodType = "";
    private String idealBodyType = "";
    private String duration = "";
    private String stability = "";
    private String skin = "";
    private String relationship = "";
    private String height = "";
    private String weight = "";
    private boolean registerDataChange = false;

    public UserModel(Context context){
        this._context = context;
        loadFromPreferences();
    }

    public void loadFromPreferences(){
        setAuthKey(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_AUTHKEY, ""));
        setEmail(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_EMAIL, ""));
        setPassword(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_PASSWORD, ""));
        setBirthdate(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_BIRTHDATE, ""));
        setPrefacture(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_PREFACTURE, ""));
        setBloodType(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_BLOODTYPE, ""));
        setIdealBodyType(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_BODYTYPE, ""));
        setPeriod(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_DURATIONPERIOD, ""));
        setStability(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_STABILITY, ""));
        setSkin(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_SKINTYPE, ""));
        setRelationship(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_RELATIONSHIP, ""));
        setHeight(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_HEIGHT, ""));
        setWeight(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_WEIGHT, ""));
        setRegisterDataChange(ActivityUtil.getSharedPreferenceBoolean(_context, USER_DATA_FIELD_REGISTER_DATACHANGE, false));
    }

    public void saveIntoPreferences(){
        saveIntoPreferences(true);
    }
    public void saveIntoPreferences(boolean datachanged){
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_AUTHKEY, getAuthKey());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_EMAIL, getEmail());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_PASSWORD, getPassword());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_BIRTHDATE, getBirthdate());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_PREFACTURE, getPrefacture());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_BLOODTYPE, getBloodType());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_BODYTYPE, getIdealBodyType());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_DURATIONPERIOD, getPeriod());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_STABILITY, getStability());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_SKINTYPE, getSkin());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_RELATIONSHIP, getRelationship());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_HEIGHT, getHeight());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_WEIGHT, getWeight());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_REGISTER_DATACHANGE, datachanged);
    }

    public String getAuthKey() {
        return authKey;
    }

    public void setAuthKey(String authKey) {
        this.authKey = authKey;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getBirthdate() {
        return birthdate;
    }

    public void setBirthdate(String birthdate) {
        this.birthdate = birthdate;
    }

    public String getPrefacture() {
        return prefacture;
    }

    public void setPrefacture(String prefacture) {
        this.prefacture = prefacture;
    }

    public String getBloodType() {
        return bloodType;
    }

    public void setBloodType(String bloodType) {
        this.bloodType = bloodType;
    }

    public String getIdealBodyType() {
        return idealBodyType;
    }

    public void setIdealBodyType(String idealBodyType) {
        this.idealBodyType = idealBodyType;
    }

    public String getPeriod() {
        return duration;
    }

    public void setPeriod(String period) {
        this.duration = period;
    }

    public String getSkin() {
        return skin;
    }

    public void setSkin(String skin) {
        this.skin = skin;
    }

    public String getRelationship() {
        return relationship;
    }

    public void setRelationship(String relationship) {
        this.relationship = relationship;
    }

    public String getHeight() {
        return height;
    }

    public void setHeight(String height) {
        this.height = height;
    }

    public String getWeight() {
        return weight;
    }

    public void setWeight(String weight) {
        this.weight = weight;
    }

    public boolean isRegisterDataChange() {
        return registerDataChange;
    }

    public void setRegisterDataChange(boolean registerDataChange) {
        this.registerDataChange = registerDataChange;
    }

    public String getStability() {
        return stability;
    }

    public void setStability(String stability) {
        this.stability = stability;
    }

    public void setRegistrationChanged(boolean dataChange) {
        this.registerDataChange = dataChange;
    }

    public String toString(){
        String str = "";

        str += "authKey: " + authKey + "\n";
        str += "email: " + email + "\n";
        str += "password: " + password + "\n";
        str += "birthdate: " + birthdate + "\n";
        str += "prefacture: " + prefacture + "\n";
        str += "bloodType: " + bloodType + "\n";
        str += "idealBodyType: " + idealBodyType + "\n";
        str += "duration: " + duration + "\n";
        str += "stability: " + stability + "\n";
        str += "skin: " + skin + "\n";
        str += "relationship: " + relationship + "\n";
        str += "height: " + height + "\n";
        str += "weight: " + weight + "\n";
        str += "registerDataChange: " + (registerDataChange ? "true" : "false") + "\n";

        return str;
    }

}

public static final String USER_DATA_FIELD_NAME_AUTHKEY = "new_AuthKey";
public static final String USER_DATA_FIELD_NAME_EMAIL = "new_Email";
public static final String USER_DATA_FIELD_NAME_PASSWORD = "new_Password";
public static final String USER_DATA_FIELD_NAME_BIRTHDATE = "new_Birthday";
public static final String USER_DATA_FIELD_NAME_PREFACTURE = "new_Prefacture";
public static final String USER_DATA_FIELD_NAME_BLOODTYPE = "new_BloodType";
public static final String USER_DATA_FIELD_NAME_BODYTYPE = "new_IdealBodyType";
public static final String USER_DATA_FIELD_NAME_DURATIONPERIOD = "new_Duration";
public static final String USER_DATA_FIELD_NAME_STABILITY = "new_Stability";
public static final String USER_DATA_FIELD_NAME_SKINTYPE = "new_Skin";
public static final String USER_DATA_FIELD_NAME_RELATIONSHIP = "new_Relationship";
public static final String USER_DATA_FIELD_NAME_HEIGHT = "new_Height";
public static final String USER_DATA_FIELD_NAME_WEIGHT = "new_Weight";
public static final String USER_DATA_FIELD_NAME_PHY_1 = "new_phy1";
public static final String USER_DATA_FIELD_NAME_PHY_2 = "new_phy2";

上面代码中的

DataConstant

只是一个包含如下常量变量的类：

package tv.gsgw.android.garusuta.model;

import id.flwi.util.ActivityUtil;
import tv.gsgw.android.garusuta.constant.DataConstant;
import android.content.Context;

public class UserModel implements DataConstant {
    Context _context;

    private String authKey = "";
    private String email = "";
    private String password = "";
    private String birthdate = "";
    private String prefacture = "";
    private String bloodType = "";
    private String idealBodyType = "";
    private String duration = "";
    private String stability = "";
    private String skin = "";
    private String relationship = "";
    private String height = "";
    private String weight = "";
    private boolean registerDataChange = false;

    public UserModel(Context context){
        this._context = context;
        loadFromPreferences();
    }

    public void loadFromPreferences(){
        setAuthKey(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_AUTHKEY, ""));
        setEmail(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_EMAIL, ""));
        setPassword(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_PASSWORD, ""));
        setBirthdate(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_BIRTHDATE, ""));
        setPrefacture(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_PREFACTURE, ""));
        setBloodType(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_BLOODTYPE, ""));
        setIdealBodyType(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_BODYTYPE, ""));
        setPeriod(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_DURATIONPERIOD, ""));
        setStability(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_STABILITY, ""));
        setSkin(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_SKINTYPE, ""));
        setRelationship(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_RELATIONSHIP, ""));
        setHeight(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_HEIGHT, ""));
        setWeight(ActivityUtil.getSharedPreferenceString(_context, USER_DATA_FIELD_NAME_WEIGHT, ""));
        setRegisterDataChange(ActivityUtil.getSharedPreferenceBoolean(_context, USER_DATA_FIELD_REGISTER_DATACHANGE, false));
    }

    public void saveIntoPreferences(){
        saveIntoPreferences(true);
    }
    public void saveIntoPreferences(boolean datachanged){
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_AUTHKEY, getAuthKey());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_EMAIL, getEmail());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_PASSWORD, getPassword());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_BIRTHDATE, getBirthdate());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_PREFACTURE, getPrefacture());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_BLOODTYPE, getBloodType());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_BODYTYPE, getIdealBodyType());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_DURATIONPERIOD, getPeriod());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_STABILITY, getStability());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_SKINTYPE, getSkin());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_RELATIONSHIP, getRelationship());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_HEIGHT, getHeight());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_NAME_WEIGHT, getWeight());
        ActivityUtil.setSharedPreference(_context, USER_DATA_FIELD_REGISTER_DATACHANGE, datachanged);
    }

    public String getAuthKey() {
        return authKey;
    }

    public void setAuthKey(String authKey) {
        this.authKey = authKey;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getBirthdate() {
        return birthdate;
    }

    public void setBirthdate(String birthdate) {
        this.birthdate = birthdate;
    }

    public String getPrefacture() {
        return prefacture;
    }

    public void setPrefacture(String prefacture) {
        this.prefacture = prefacture;
    }

    public String getBloodType() {
        return bloodType;
    }

    public void setBloodType(String bloodType) {
        this.bloodType = bloodType;
    }

    public String getIdealBodyType() {
        return idealBodyType;
    }

    public void setIdealBodyType(String idealBodyType) {
        this.idealBodyType = idealBodyType;
    }

    public String getPeriod() {
        return duration;
    }

    public void setPeriod(String period) {
        this.duration = period;
    }

    public String getSkin() {
        return skin;
    }

    public void setSkin(String skin) {
        this.skin = skin;
    }

    public String getRelationship() {
        return relationship;
    }

    public void setRelationship(String relationship) {
        this.relationship = relationship;
    }

    public String getHeight() {
        return height;
    }

    public void setHeight(String height) {
        this.height = height;
    }

    public String getWeight() {
        return weight;
    }

    public void setWeight(String weight) {
        this.weight = weight;
    }

    public boolean isRegisterDataChange() {
        return registerDataChange;
    }

    public void setRegisterDataChange(boolean registerDataChange) {
        this.registerDataChange = registerDataChange;
    }

    public String getStability() {
        return stability;
    }

    public void setStability(String stability) {
        this.stability = stability;
    }

    public void setRegistrationChanged(boolean dataChange) {
        this.registerDataChange = dataChange;
    }

    public String toString(){
        String str = "";

        str += "authKey: " + authKey + "\n";
        str += "email: " + email + "\n";
        str += "password: " + password + "\n";
        str += "birthdate: " + birthdate + "\n";
        str += "prefacture: " + prefacture + "\n";
        str += "bloodType: " + bloodType + "\n";
        str += "idealBodyType: " + idealBodyType + "\n";
        str += "duration: " + duration + "\n";
        str += "stability: " + stability + "\n";
        str += "skin: " + skin + "\n";
        str += "relationship: " + relationship + "\n";
        str += "height: " + height + "\n";
        str += "weight: " + weight + "\n";
        str += "registerDataChange: " + (registerDataChange ? "true" : "false") + "\n";

        return str;
    }

}

public static final String USER_DATA_FIELD_NAME_AUTHKEY = "new_AuthKey";
public static final String USER_DATA_FIELD_NAME_EMAIL = "new_Email";
public static final String USER_DATA_FIELD_NAME_PASSWORD = "new_Password";
public static final String USER_DATA_FIELD_NAME_BIRTHDATE = "new_Birthday";
public static final String USER_DATA_FIELD_NAME_PREFACTURE = "new_Prefacture";
public static final String USER_DATA_FIELD_NAME_BLOODTYPE = "new_BloodType";
public static final String USER_DATA_FIELD_NAME_BODYTYPE = "new_IdealBodyType";
public static final String USER_DATA_FIELD_NAME_DURATIONPERIOD = "new_Duration";
public static final String USER_DATA_FIELD_NAME_STABILITY = "new_Stability";
public static final String USER_DATA_FIELD_NAME_SKINTYPE = "new_Skin";
public static final String USER_DATA_FIELD_NAME_RELATIONSHIP = "new_Relationship";
public static final String USER_DATA_FIELD_NAME_HEIGHT = "new_Height";
public static final String USER_DATA_FIELD_NAME_WEIGHT = "new_Weight";
public static final String USER_DATA_FIELD_NAME_PHY_1 = "new_phy1";
public static final String USER_DATA_FIELD_NAME_PHY_2 = "new_phy2";

这使用了一个实用程序类，该类还创建了一个用于帮助处理

SharedReferences

Easter的实用程序类：

package id.flwi.util;

/**
 * @author Arief Bayu Purwanto
 */
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.util.Calendar;

import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.util.Log;

public class ActivityUtil {
    public static final String PREFS_NAME = "____MyPrefsFile";

    public static void debugExtra(Bundle extras){
        if( extras != null) {
            Log.i("Log", "printing all extras information");
            java.util.Set<String> keys = extras.keySet();
            java.util.Iterator<String> keyIterator = keys.iterator();
            int index = 0;
            while(keyIterator.hasNext()) {
                Log.i("log", "  extras #" + (++index) + ": " + keyIterator.next());
            }
        } else {
            Log.i("Log", "empty extras");
        }
    }

    public static boolean getSharedPreferenceBoolean(Context c, String preference){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        return settings.getBoolean(preference, false);
    }
    public static boolean getSharedPreferenceBoolean(Context c, String preference, boolean defaultValue){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        return settings.getBoolean(preference, defaultValue);
    }
    public static String getSharedPreferenceString(Context c, String preference){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        return settings.getString(preference, "");
    }
    public static String getSharedPreferenceString(Context c, String preference, String defaultValue){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        return settings.getString(preference, defaultValue);
    }
    public static int getSharedPreferenceInt(Context c, String preference, int defaultValue){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        return settings.getInt(preference, defaultValue);
    }

    public static long getSharedPreferenceLong(Context c, String preference, long defaultValue){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        return settings.getLong(preference, defaultValue);
    }

    public static void setSharedPreference(Context c, String preference, boolean prefValue){

        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        SharedPreferences.Editor editor = settings.edit();
        editor.putBoolean(preference, prefValue);
        editor.commit();
    }

    public static void setSharedPreference(Context c, String preference, Long prefValue){

        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        SharedPreferences.Editor editor = settings.edit();
        editor.putLong(preference, prefValue);
        editor.commit();
    }

    public static void setSharedPreference(Context c, String preference, int prefValue){

        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        SharedPreferences.Editor editor = settings.edit();
        editor.putInt(preference, prefValue);
        editor.commit();
    }
    public static void setSharedPreference(Context c, String preference, String prefValue){
        SharedPreferences settings = c.getSharedPreferences(ActivityUtil.PREFS_NAME, 0);
        SharedPreferences.Editor editor = settings.edit();
        editor.putString(preference, prefValue);
        editor.commit();
    }

}

要更改或检索数据，只需调用其关联的字段getter/setter：

sharedData.getPassword();
sharedData.setPassword("new password");

最后，如果您更改字段，请不要忘记调用

saventopreferences

：

sharedData.saveIntoPreferences();

---

希望这有助于解决您的问题。

在我看来，尽量减少在项目中使用“上下文”，以避免内存泄漏或加载不必要的资源

共享首选项是一个不错的选择，但需要使用应用程序或activit的上下文。当您想要持久化某些动态值时经常使用，是这样吗

Java接口只使用最终成员（静态），并且在代码中非常紧凑且易于使用（记住）。尝试使用“始终拥有静态可变成员”（如ip、密码等）

此外，通过示例，使用枚举管理应用程序中的状态或其他内容

public  interface Preferences {
    public String HOST = "http://xxx.xxx.xxx.xxx";
    public String PREF1 = "pref1";
    public String PREF2 = "pref2"; 
    public enum Connection { CONNECTED, DISCONNECTED, UNKNOWN }
}

---

使用java类或SharedReference取决于您，它们之间的区别就是您的目的。 在我看来，如果您想保存常量，只需使用扩展枚举的java类即可。

---

否则，用户数据、存储在SharedReference中的会话数据，您可以参考ariefbayu的答案，但在我的建议中，请使用reflect获取字段值。

对于布局文件中需要使用的资源，我更喜欢使用

strings.xml

。

---

对于需要在类中访问的变量，我更喜欢

接口

方式。

如果可以的话，将其存储在java中。若有必要，将其存储在conf文件中。为什么要在接口中保存首选项？？？问题是可以在xml文件中定义首选项（PreferenceScreen、PreferenceCategory等）。在这种情况下，我们应该定义android:key-value，从那里我们不能访问java类。android也一样：DefaultValue这是正确的答案。其他答案很简单，但我猜当时其他作者对Android不感兴趣。问题是，也可以在xml布局中定义首选项，并且在该位置还应该提供键和默认值。如果这些是在java类中定义的，则会出现问题，因为从xml我们将无法访问这些常量