Java 比较整数时出现奇怪的错误

Java 比较整数时出现奇怪的错误,java,android,integer,int,compare,Java,Android,Integer,Int,Compare,我有一个奇怪的错误,首先是这个类给了我错误 public class SpeciePesci { public static final SpeciePesce[] specie = (new SpeciePesce[]{ new SpeciePesce(13,"Trota fario", R.drawable.specie_trota_fario, R.string.specie_descrizione_trota_fario), new SpeciePesce(14,"T

我有一个奇怪的错误,首先是这个类给了我错误

public class SpeciePesci {


public static final SpeciePesce[] specie = (new SpeciePesce[]{
    new SpeciePesce(13,"Trota fario", R.drawable.specie_trota_fario, R.string.specie_descrizione_trota_fario),
    new SpeciePesce(14,"Trota iridea", R.drawable.specie_trota_iridea, R.string.specie_descrizione_trota_iridea),
    new SpeciePesce(4,"Trota marmorata", R.drawable.specie_trota_marmorata, R.string.specie_descrizione_trota_marmorata),
    new SpeciePesce(15,"Trota lacustre", R.drawable.specie_trota_lacustre, R.string.specie_descrizione_trota_lacustre),
    new SpeciePesce(195,"Salmerino alpino", R.drawable.specie_salmerino_alpino, R.string.specie_descrizione_salmerino_alpino),
    new SpeciePesce(18,"Salmerino di fonte", R.drawable.specie_salmerino_fonte, R.string.specie_descrizione_salmerino_fonte),
    new SpeciePesce(19,"Carpa", R.drawable.specie_carpa, R.string.specie_descrizione_carpa),
    new SpeciePesce(20,"Tinca", R.drawable.specie_tinca, R.string.specie_descrizione_tinca),
    new SpeciePesce(16,"Temolo", R.drawable.specie_temolo, R.string.specie_descrizione_temolo),
    new SpeciePesce(22,"Persico reale", R.drawable.specie_persico_reale, R.string.specie_descrizione_persico_reale),
    new SpeciePesce(21,"Lucio", R.drawable.specie_lucio, R.string.specie_descrizione_lucio)
});


public static Integer getPosition(Integer id){
    Integer pos=  -1;
    if(195==195){
        Log.d("INT==","195==195  ?? OK");

    }
    if(id==195){
        Log.d("INT==","ID==195  ?? OK");

    }
    for (int i = 0; i < specie.length; i++) {
        if(specie[i].getId()==195){
            Log.d("INT==","getID==195  ?? OK");

        }
        Log.d("INT==",""+specie[i].getId()+"=="+id);
        if (specie[i].getId()==id ) {
                Log.d("INT==","OK");
                pos = i;
                break;
        }
    }
    return pos;
}
}
当我调用getPosition(X)方法时,假设我接收到具有该Id的项的数组中的位置;在此之前,它很简单,除了195之外,它对所有ID都很有效。当它比较195==195时,它给了我假。。可能是什么

正如我所看到的,我记录了各种情况,结果如下

05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 195==195  ?? OK
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ ID==195  ?? OK
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 13==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 14==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 4==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 15==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ getID==195  ?? OK
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 195==195  << suppose the loop stop here
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 18==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 19==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 20==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 16==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 22==195
05-23 14:30:28.665      560-560/com.evosw.altosarca D/INT==﹕ 21==195

可能是什么这是因为您没有使用原语
int
类型。您使用的是reference
Integer
类型。您的
getPosition()
方法返回
Integer

当使用
==
运算符比较两个引用时,实际上是比较它的引用,而不是它的值。如果要检查两个对象是否有意义地相等,请使用
equals()

但请注意,如果要比较的两个
整数
都小于128,则比较应返回true。
注意:

    Integer a = 101;
    Integer b = 101;
    Integer c = 1234;
    Integer d = 1234;
    Integer e = a;


    System.out.println(a==b); //true - same reference; for explanation read the attached link
    System.out.println(a==e); //true - same reference; 'e' referencing 'a'
    System.out.println(c==d); //false - diffrent reference
    System.out.println(c.equals(d)); //true - meaningfully equals 

您可以阅读以了解更多详细信息。

我确实发现了数字大于127的错误,因此从128和更高的数字中,我有这个错误。。。。uhmm@Jonik,谢谢你找到它。这是我刚刚纠正的一个打字错误。
05-23 14:35:30.068    3153-3153/com.evosw.altosarca D/INT==﹕ 195==195  ?? OK
05-23 14:35:30.068    3153-3153/com.evosw.altosarca D/INT==﹕ 13==13
05-23 14:35:30.068    3153-3153/com.evosw.altosarca D/INT==﹕ OK
05-23 14:35:30.103    3153-3153/com.evosw.altosarca D/INT==﹕ 195==195  ?? OK
05-23 14:35:30.103    3153-3153/com.evosw.altosarca D/INT==﹕ 13==13
05-23 14:35:30.103    3153-3153/com.evosw.altosarca D/INT==﹕ OK
05-23 14:35:30.103    3153-3153/com.evosw.altosarca D/INT==﹕ 195==195  ?? OK
05-23 14:35:30.103    3153-3153/com.evosw.altosarca D/INT==﹕ 13==13
05-23 14:35:30.103    3153-3153/com.evosw.altosarca D/INT==﹕ OK
    Integer a = 101;
    Integer b = 101;
    Integer c = 1234;
    Integer d = 1234;
    Integer e = a;


    System.out.println(a==b); //true - same reference; for explanation read the attached link
    System.out.println(a==e); //true - same reference; 'e' referencing 'a'
    System.out.println(c==d); //false - diffrent reference
    System.out.println(c.equals(d)); //true - meaningfully equals