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Diffstat (limited to 'src/jniproj.cpp')
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diff --git a/src/jniproj.cpp b/src/jniproj.cpp new file mode 100644 index 00000000..67aa2478 --- /dev/null +++ b/src/jniproj.cpp @@ -0,0 +1,472 @@ +/****************************************************************************** + * Project: PROJ.4 + * Purpose: Java/JNI wrappers for PROJ API. + * Author: Antonello Andrea + * Martin Desruisseaux + * + ****************************************************************************** + * Copyright (c) 2005, Andrea Antonello + * Copyright (c) 2011, Martin Desruisseaux + * Copyright (c) 2018, Even Rouault + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + *****************************************************************************/ + +/*! + * \file jniproj.c + * + * \brief + * Functions used by the Java Native Interface (JNI) wrappers of PROJ. + * + * + * \author Antonello Andrea + * \date Wed Oct 20 23:10:24 CEST 2004 + * + * \author Martin Desruisseaux + * \date August 2011 + */ + +#include "proj_config.h" + +#ifdef JNI_ENABLED + +#include <math.h> +#include <string.h> +#include "projects.h" +#include "org_proj4_PJ.h" +#include <jni.h> + +#define PJ_FIELD_NAME "ptr" +#define PJ_FIELD_TYPE "J" + +/*! + * \brief + * Internal method returning the address of the PJ structure wrapped by the given Java object. + * This function looks for a field named "ptr" and of type "long" (Java signature "J") in the + * given object. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The address of the PJ structure, or NULL if the operation fails (for example + * because the "ptr" field was not found). + */ +PJ *getPJ(JNIEnv *env, jobject object) +{ + jfieldID id = (*env)->GetFieldID(env, (*env)->GetObjectClass(env, object), PJ_FIELD_NAME, PJ_FIELD_TYPE); + return (id) ? (PJ*) (*env)->GetLongField(env, object, id) : NULL; +} + +/*! + * \brief + * Internal method returning the java.lang.Double.NaN constant value. + * Efficiency is no a high concern for this particular method, because it + * is used mostly when the user wrongly attempt to use a disposed PJ object. + * + * \param env - The JNI environment. + * \return The java.lang.Double.NaN constant value. + */ +jdouble javaNaN(JNIEnv *env) +{ + jclass c = (*env)->FindClass(env, "java/lang/Double"); + if (c) { // Should never be NULL, but let be paranoiac. + jfieldID id = (*env)->GetStaticFieldID(env, c, "NaN", "D"); + if (id) { // Should never be NULL, but let be paranoiac. + return (*env)->GetStaticDoubleField(env, c, id); + } + } + return 0.0; // Should never happen. +} + +/*! + * \brief + * Returns the Proj4 release number. + * + * \param env - The JNI environment. + * \param class - The class from which this method has been invoked. + * \return The Proj4 release number, or NULL. + */ +JNIEXPORT jstring JNICALL Java_org_proj4_PJ_getVersion + (JNIEnv *env, jclass class) +{ + const char *desc = pj_get_release(); + return (desc) ? (*env)->NewStringUTF(env, desc) : NULL; +} + +/*! + * \brief + * Allocates a new PJ structure from a definition string. + * + * \param env - The JNI environment. + * \param class - The class from which this method has been invoked. + * \param definition - The string definition to be given to Proj4. + * \return The address of the new PJ structure, or 0 in case of failure. + */ +JNIEXPORT jlong JNICALL Java_org_proj4_PJ_allocatePJ + (JNIEnv *env, jclass class, jstring definition) +{ + const char *def_utf = (*env)->GetStringUTFChars(env, definition, NULL); + if (!def_utf) return 0; /* OutOfMemoryError already thrown. */ + PJ *pj = pj_init_plus(def_utf); + (*env)->ReleaseStringUTFChars(env, definition, def_utf); + return (jlong) pj; +} + +/*! + * \brief + * Allocates a new geographic PJ structure from an existing one. + * + * \param env - The JNI environment. + * \param class - The class from which this method has been invoked. + * \param projected - The PJ object from which to derive a new one. + * \return The address of the new PJ structure, or 0 in case of failure. + */ +JNIEXPORT jlong JNICALL Java_org_proj4_PJ_allocateGeoPJ + (JNIEnv *env, jclass class, jobject projected) +{ + PJ *pj = getPJ(env, projected); + return (pj) ? (jlong) pj_latlong_from_proj(pj) : 0; +} + +/*! + * \brief + * Returns the definition string. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The definition string. + */ +JNIEXPORT jstring JNICALL Java_org_proj4_PJ_getDefinition + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + if (pj) { + char *desc = pj_get_def(pj, 0); + if (desc) { + jstring str = (*env)->NewStringUTF(env, desc); + pj_dalloc(desc); + return str; + } + } + return NULL; +} + +/*! + * \brief + * Returns the description associated to the PJ structure. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The description associated to the PJ structure. + */ +JNIEXPORT jstring JNICALL Java_org_proj4_PJ_toString + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + if (pj) { + const char *desc = pj->descr; + if (desc) { + return (*env)->NewStringUTF(env, desc); + } + } + return NULL; +} + +/*! + * \brief + * Returns the CRS type as one of the PJ.Type enum: GEOGRAPHIC, GEOCENTRIC or PROJECTED. + * This function should never return NULL, unless class or fields have been renamed in + * such a way that we can not find anymore the expected enum values. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The CRS type as one of the PJ.Type enum. + */ +JNIEXPORT jobject JNICALL Java_org_proj4_PJ_getType + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + if (pj) { + const char *type; + if (pj_is_latlong(pj)) { + type = "GEOGRAPHIC"; + } else if (pj_is_geocent(pj)) { + type = "GEOCENTRIC"; + } else { + type = "PROJECTED"; + } + jclass c = (*env)->FindClass(env, "org/proj4/PJ$Type"); + if (c) { + jfieldID id = (*env)->GetStaticFieldID(env, c, type, "Lorg/proj4/PJ$Type;"); + if (id) { + return (*env)->GetStaticObjectField(env, c, id); + } + } + } + return NULL; +} + +/*! + * \brief + * Returns the semi-major axis length. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The semi-major axis length. + */ +JNIEXPORT jdouble JNICALL Java_org_proj4_PJ_getSemiMajorAxis + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + return pj ? pj->a_orig : javaNaN(env); +} + +/*! + * \brief + * Computes the semi-minor axis length from the semi-major axis length and the eccentricity + * squared. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The semi-minor axis length. + */ +JNIEXPORT jdouble JNICALL Java_org_proj4_PJ_getSemiMinorAxis + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + if (!pj) return javaNaN(env); + double a = pj->a_orig; + return sqrt(a*a * (1.0 - pj->es_orig)); +} + +/*! + * \brief + * Returns the eccentricity squared. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The eccentricity. + */ +JNIEXPORT jdouble JNICALL Java_org_proj4_PJ_getEccentricitySquared + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + return pj ? pj->es_orig : javaNaN(env); +} + +/*! + * \brief + * Returns an array of character indicating the direction of each axis. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The axis directions. + */ +JNIEXPORT jcharArray JNICALL Java_org_proj4_PJ_getAxisDirections + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + if (pj) { + int length = strlen(pj->axis); + jcharArray array = (*env)->NewCharArray(env, length); + if (array) { + jchar* axis = (*env)->GetCharArrayElements(env, array, NULL); + if (axis) { + /* Don't use memcp because the type may not be the same. */ + int i; + for (i=0; i<length; i++) { + axis[i] = pj->axis[i]; + } + (*env)->ReleaseCharArrayElements(env, array, axis, 0); + } + return array; + } + } + return NULL; +} + +/*! + * \brief + * Longitude of the prime meridian measured from the Greenwich meridian, positive eastward. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The prime meridian longitude, in degrees. + */ +JNIEXPORT jdouble JNICALL Java_org_proj4_PJ_getGreenwichLongitude + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + return (pj) ? (pj->from_greenwich)*(180/M_PI) : javaNaN(env); +} + +/*! + * \brief + * Returns the conversion factor from linear units to metres. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \param vertical - JNI_FALSE for horizontal axes, or JNI_TRUE for the vertical axis. + * \return The conversion factor to metres. + */ +JNIEXPORT jdouble JNICALL Java_org_proj4_PJ_getLinearUnitToMetre + (JNIEnv *env, jobject object, jboolean vertical) +{ + PJ *pj = getPJ(env, object); + if (pj) { + return (vertical) ? pj->vto_meter : pj->to_meter; + } + return javaNaN(env); +} + +/*! + * \brief + * Converts input values from degrees to radians before coordinate operation, or the output + * values from radians to degrees after the coordinate operation. + * + * \param pj - The PROJ.4 PJ structure. + * \param data - The coordinate array to transform. + * \param numPts - Number of points to transform. + * \param dimension - Dimension of points in the coordinate array. + * \param factor - The scale factor to apply: M_PI/180 for inputs or 180/M_PI for outputs. + */ +void convertAngularOrdinates(PJ *pj, double* data, jint numPts, int dimension, double factor) { + int dimToSkip; + if (pj_is_latlong(pj)) { + /* Convert only the 2 first ordinates and skip all the other dimensions. */ + dimToSkip = dimension - 2; + } else { + /* Not a geographic CRS: nothing to convert. */ + return; + } + double *stop = data + dimension*numPts; + if (dimToSkip > 0) { + while (data != stop) { + (*data++) *= factor; + (*data++) *= factor; + data += dimToSkip; + } + } else { + while (data != stop) { + (*data++) *= factor; + } + } +} + +/*! + * \brief + * Transforms in-place the coordinates in the given array. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \param target - The target CRS. + * \param dimension - The dimension of each coordinate value. Must be equals or greater than 2. + * \param coordinates - The coordinates to transform, as a sequence of (x,y,<z>,...) tuples. + * \param offset - Offset of the first coordinate in the given array. + * \param numPts - Number of points to transform. + */ +JNIEXPORT void JNICALL Java_org_proj4_PJ_transform + (JNIEnv *env, jobject object, jobject target, jint dimension, jdoubleArray coordinates, jint offset, jint numPts) +{ + if (!target || !coordinates) { + jclass c = (*env)->FindClass(env, "java/lang/NullPointerException"); + if (c) (*env)->ThrowNew(env, c, "The target CRS and the coordinates array can not be null."); + return; + } + if (dimension < 2 || dimension > org_proj4_PJ_DIMENSION_MAX) { /* Arbitrary upper value for catching potential misuse. */ + jclass c = (*env)->FindClass(env, "java/lang/IllegalArgumentException"); + if (c) (*env)->ThrowNew(env, c, "Illegal number of dimensions."); + return; + } + if ((offset < 0) || (numPts < 0) || (offset + dimension*numPts) > (*env)->GetArrayLength(env, coordinates)) { + jclass c = (*env)->FindClass(env, "java/lang/ArrayIndexOutOfBoundsException"); + if (c) (*env)->ThrowNew(env, c, "Illegal offset or illegal number of points."); + return; + } + PJ *src_pj = getPJ(env, object); + PJ *dst_pj = getPJ(env, target); + if (src_pj && dst_pj) { + /* Using GetPrimitiveArrayCritical/ReleasePrimitiveArrayCritical rather than + GetDoubleArrayElements/ReleaseDoubleArrayElements increase the chances that + the JVM returns direct reference to its internal array without copying data. + However we must promise to run the "critical" code fast, to not make any + system call that may wait for the JVM and to not invoke any other JNI method. */ + double *data = (*env)->GetPrimitiveArrayCritical(env, coordinates, NULL); + if (data) { + double *x = data + offset; + double *y = x + 1; + double *z = (dimension >= 3) ? y+1 : NULL; + convertAngularOrdinates(src_pj, x, numPts, dimension, M_PI/180); + int err = pj_transform(src_pj, dst_pj, numPts, dimension, x, y, z); + convertAngularOrdinates(dst_pj, x, numPts, dimension, 180/M_PI); + (*env)->ReleasePrimitiveArrayCritical(env, coordinates, data, 0); + if (err) { + jclass c = (*env)->FindClass(env, "org/proj4/PJException"); + if (c) (*env)->ThrowNew(env, c, pj_strerrno(err)); + } + } + } +} + +/*! + * \brief + * Returns a description of the last error that occurred, or NULL if none. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + * \return The last error, or NULL. + */ +JNIEXPORT jstring JNICALL Java_org_proj4_PJ_getLastError + (JNIEnv *env, jobject object) +{ + PJ *pj = getPJ(env, object); + if (pj) { + int err = pj_ctx_get_errno(pj->ctx); + if (err) { + return (*env)->NewStringUTF(env, pj_strerrno(err)); + } + } + return NULL; +} + +/*! + * \brief + * Deallocate the PJ structure. This method is invoked by the garbage collector exactly once. + * This method will also set the Java "ptr" final field to 0 as a safety. In theory we are not + * supposed to change the value of a final field. But no Java code should use this field, and + * the PJ object is being garbage collected anyway. We set the field to 0 as a safety in case + * some user invoked the finalize() method explicitly despite our warning in the Javadoc to + * never do such thing. + * + * \param env - The JNI environment. + * \param object - The Java object wrapping the PJ structure (not allowed to be NULL). + */ +JNIEXPORT void JNICALL Java_org_proj4_PJ_finalize + (JNIEnv *env, jobject object) +{ + jfieldID id = (*env)->GetFieldID(env, (*env)->GetObjectClass(env, object), PJ_FIELD_NAME, PJ_FIELD_TYPE); + if (id) { + PJ *pj = (PJ*) (*env)->GetLongField(env, object, id); + if (pj) { + (*env)->SetLongField(env, object, id, (jlong) 0); + pj_free(pj); + } + } +} + +#endif |