string.c

来自「This is a resource based on j2me embedde」· C语言 代码 · 共 613 行 · 第 1/2 页

    v2 = (CVMArrayOfChar *)valueObject2; 

    FIELD_READ_OFFSET(thisStringObject, i);
    FIELD_READ_OFFSET(anotherStringObject, j);

    /* Now compare */
    if (i == j) {
        /* This is an optimized case */
        while (n-- > 0) {
	    CVMD_arrayReadChar(v1, i, c1);
	    CVMD_arrayReadChar(v2, i, c2);
	    if (c1 != c2) {
		arguments[0].j.i = (CVMJavaInt)c1 - (CVMJavaInt)c2;
		return CNI_SINGLE;
	    }
	    i++;
        }
    } else {
        while (n-- > 0) {
	    CVMD_arrayReadChar(v1, i, c1);
	    CVMD_arrayReadChar(v2, j, c2);
	    i++;
	    j++;
	    if (c1 != c2) {
		arguments[0].j.i = (CVMJavaInt)c1 - (CVMJavaInt)c2;
		return CNI_SINGLE;
	    }
	}
    }
    arguments[0].j.i = len1 - len2;
    return CNI_SINGLE;
}

/*
 * Class:       java/lang/String
 * Method:      hashCode
 * Signature:   ()I
 */
CNIEXPORT CNIResultCode
CNIjava_lang_String_hashCode(CVMExecEnv* ee, CVMStackVal32 *arguments,
                             CVMMethodBlock **p_mb)
{
    CVMObjectICell * thisICell = &arguments[0].j.r;
    CVMObject *thisObject = CVMID_icellDirect(ee, thisICell);
    CVMObject *valueObject;
    CVMArrayOfChar *value;
    CVMJavaInt offset;
    CVMJavaInt count;
    CVMJavaChar c;
    CVMJavaInt h = 0;

    FIELD_READ_VALUE(thisObject, valueObject);
    FIELD_READ_OFFSET(thisObject, offset);
    FIELD_READ_COUNT(thisObject, count);
    value = (CVMArrayOfChar *)valueObject; 

    while (count-- > 0 ) {
	CVMD_arrayReadChar(value, offset, c); 
	h = 31*h + (CVMJavaInt)c;
	offset ++;
    }
    arguments[0].j.i = h;
    return CNI_SINGLE; 
}

/*
 * Helper function for indexOf(I)I and indexOf(II)I.
 */
static CVMJavaInt
stringIndexOfHelper1(CVMExecEnv* ee,  CVMObjectICell *thisICell,
                     CVMJavaInt ch, CVMJavaInt fromIndex) 
{
    CVMObject *thisObj = CVMID_icellDirect(ee, thisICell);
    CVMObject *valueObj;
    CVMArrayOfChar *valueArr;
    CVMJavaInt offset;
    CVMJavaInt count;
    CVMJavaInt max;
    CVMJavaInt i;
    CVMJavaChar c;

    FIELD_READ_COUNT(thisObj, count);
 
    /* The argument fromIndex is always >=0. Guaranteed by caller.*/ 
    if (fromIndex >= count) {
        return -1;
    }
   
    FIELD_READ_OFFSET(thisObj, offset);
    FIELD_READ_VALUE(thisObj, valueObj);
    valueArr = (CVMArrayOfChar *)valueObj;

    max = offset + count;
    i = offset + fromIndex;
    while (i < max) {
	CVMD_arrayReadChar(valueArr, i, c);
	if (c == ch) {
	    return i - offset;
	}
	i++;
    }
    /* Not found. Return -1. */
    return -1;
}

/*
 * Class:       java/lang/String
 * Method:      indexOf
 * Signature:   (I)I
 */
CNIEXPORT CNIResultCode
CNIjava_lang_String_indexOf__I(CVMExecEnv* ee, CVMStackVal32 *arguments,
                               CVMMethodBlock **p_mb)
{
   CVMObjectICell *thisICell = &arguments[0].j.r;
   CVMJavaInt ch = arguments[1].j.i;

   arguments[0].j.i = stringIndexOfHelper1(ee, thisICell, ch, 0);
   return CNI_SINGLE;
}

/*
 * Class:       java/lang/String
 * Method:      indexOf
 * Signature:   (II)I
 */
CNIEXPORT CNIResultCode
CNIjava_lang_String_indexOf__II(CVMExecEnv* ee, CVMStackVal32 *arguments,
                                CVMMethodBlock **p_mb)
{
    CVMObjectICell *thisICell = &arguments[0].j.r;
    CVMJavaInt ch = arguments[1].j.i;
    CVMJavaInt fromIndex = arguments[2].j.i;

    if (fromIndex < 0) {
        fromIndex = 0;
    }
 
    arguments[0].j.i = stringIndexOfHelper1(ee, thisICell, ch, fromIndex);
    return CNI_SINGLE;
}

/*
 * Helper function for indexOf(Ljava/lang/String;)I
 * and indexOf(Ljava/lang/String;I)I.
 */
static CVMJavaInt
stringIndexOfHelper2(CVMExecEnv* ee, CVMObjectICell *thisICell,
                     CVMObjectICell *strICell, CVMJavaInt fromIndex)
{
   CVMObject *thisObj = CVMID_icellDirect(ee, thisICell);
   CVMObject *strObj = CVMID_icellDirect(ee, strICell);
   CVMObject *vObj1;
   CVMObject *vObj2;
   CVMArrayOfChar *v1;
   CVMArrayOfChar *v2;
   CVMJavaInt offset;
   CVMJavaInt strOffset;
   CVMJavaInt count;
   CVMJavaInt strCount;
   CVMJavaInt max;
   CVMJavaChar first;
   CVMJavaChar c1;
   CVMJavaChar c2;
   CVMJavaInt i; /* Iterates v1 searching for the first char of v2 */
   CVMJavaInt j; /* Iterates v1 searching for the rest of v2 */
   CVMJavaInt k; /* Iterates v2 */
   CVMJavaInt end;

   /* The caller is responsible for NULL checking for strICell. */
   FIELD_READ_COUNT(thisObj, count);
   FIELD_READ_COUNT(strObj, strCount);

   if (fromIndex >= count) {
       if (strCount == 0) {
           /* 
            * Special case: return the length of the first string
            * when searching for an empty String, 4276204
            */
           return count;
       }
       return -1;
   }
   if (fromIndex < 0) {
       fromIndex = 0;
   }
   if (strCount == 0) {
       return fromIndex;
   }

   FIELD_READ_VALUE(thisObj, vObj1);
   FIELD_READ_VALUE(strObj, vObj2);
   FIELD_READ_OFFSET(thisObj, offset);
   FIELD_READ_OFFSET(strObj, strOffset);
   v1 = (CVMArrayOfChar *)vObj1;
   v2 = (CVMArrayOfChar *)vObj2;

   CVMD_arrayReadChar(v2, strOffset, first);
   max = offset + (count - strCount);
   i = offset + fromIndex;

   while (i <= max) {
       /* Search for first character. */
       CVMD_arrayReadChar(v1, i, c1);
       if (c1 == first) {
	   /* Found first character, now look at the rest of v2 */
	   j = i + 1;
	   end = i + strCount;
	   k = strOffset + 1;
	   while(j < end) {
	       CVMD_arrayReadChar(v1, j, c1);
	       CVMD_arrayReadChar(v2, k, c2);
	       if (c1 != c2) {
		   goto continueSearch;
	       }
	       j++;
	       k++;
	   }
	   /* Found */
	   return i - offset;
       }
   continueSearch:
       i++;
   }
   /* If we are here, then we have failed to find v2 in v1.*/
   return -1;
}

/*
 * Class:       java/lang/String
 * Method:      indexOf
 * Signature:   (Ljava/lang/String;)I
 */
CNIEXPORT CNIResultCode
CNIjava_lang_String_indexOf__Ljava_lang_String_2(CVMExecEnv* ee,
                                                 CVMStackVal32 *arguments,
                                                 CVMMethodBlock **p_mb)
{
    CVMObjectICell *thisICell = &arguments[0].j.r;
    CVMObjectICell *strICell = &arguments[1].j.r;
  
    /* NULL check for the argument string */ 
    if (CVMID_icellIsNull(strICell)) {
        CVMthrowNullPointerException(ee, NULL);
        return CNI_EXCEPTION;
    }

    arguments[0].j.i = stringIndexOfHelper2(ee, thisICell, strICell, 0);
    return CNI_SINGLE;
}

/*
 * Class:       java/lang/String
 * Method:      indexOf
 * Signature:   (Ljava/lang/String;I)I
 */
CNIEXPORT CNIResultCode
CNIjava_lang_String_indexOf__Ljava_lang_String_2I(CVMExecEnv* ee, 
                                                  CVMStackVal32 *arguments,
                                                  CVMMethodBlock **p_mb)
{
   CVMObjectICell *thisICell = &arguments[0].j.r;
   CVMObjectICell *strICell = &arguments[1].j.r;
   CVMJavaInt fromIndex = arguments[2].j.i;

   /* NULL check for the argument string */
   if (CVMID_icellIsNull(strICell)) {
       CVMthrowNullPointerException(ee, NULL);
       return CNI_EXCEPTION;
   }

   arguments[0].j.i = stringIndexOfHelper2(ee, thisICell, strICell, fromIndex);
   return CNI_SINGLE;
}

/*
 * Class:       java/lang/String
 * Method:      intern
 * Signature:   ()Ljava/lang/String;
 */
CNIEXPORT CNIResultCode
CNIjava_lang_String_intern(CVMExecEnv* ee, CVMStackVal32 *arguments,
                           CVMMethodBlock **p_mb)
{
    CVMObjectICell *thisString = &arguments[0].j.r;
    JNIEnv* env = CVMexecEnv2JniEnv(ee);
    CVMObjectICell *result = NULL;

    CVMD_gcSafeExec(ee, {
        if ((*env)->PushLocalFrame(env, 4) == 0) {
            result = (CVMObjectICell *)JVM_InternString(
                env, (jobject)thisString);
            if (result != NULL) {
                CVMID_icellAssign(ee, &arguments[0].j.r, result);
            }
            (*env)->PopLocalFrame(env, NULL);
        }
    });

    if (CVMexceptionOccurred(ee)) {
        return CNI_EXCEPTION;
    }

    return CNI_SINGLE;
}