org.gstreamer.Structure Maven / Gradle / Ivy
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/*
* Copyright (c) 2009 Levente Farkas
* Copyright (C) 2009 Tamas Korodi
* Copyright (C) 2007 Wayne Meissner
* Copyright (C) 2003 David A. Schleef
*
* This code is free software: you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License version 3 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* version 3 for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with this work. If not, see
* A Structure is a collection of key/value pairs. The keys are expressed
* as GQuarks and the values can be of any GType.
*
* In addition to the key/value pairs, a Structure also has a name. The name
* starts with a letter and can be followed by letters, numbers and any of "/-_.:".
*
* Structure is used by various GStreamer subsystems to store information
* in a flexible and extensible way.
*
* A Structure can be created with new {@link #Structure(String)} or
* {@link #Structure(String, String, Object...)}, which both take a name and an
* optional set of key/value pairs along with the types of the values.
*
* Field values can be changed with set{Integer,String}() etc functions.
*
* Field values can be retrieved with get{Integer,String}() etc functions.
*
* Fields can be removed with {@link #removeField} or {@link #removeFields}
* @see Caps
* @see Event
*/
public class Structure extends NativeObject {
private static interface API extends GstStructureAPI, GstValueAPI {
@CallerOwnsReturn Pointer ptr_gst_structure_from_string(String data, PointerByReference end);
@CallerOwnsReturn Pointer ptr_gst_structure_empty_new(String name);
//Pointer gst_structure_id_empty_new(GQuark quark);
@CallerOwnsReturn Pointer ptr_gst_structure_new(String name, String firstField, Object... args);
void gst_structure_free(Pointer ptr);
}
private static final API gst = GstNative.load(API.class);
/**
* Creates a new instance of Structure
*/
public Structure(Initializer init) {
super(init);
}
private Structure(Pointer ptr) {
this(initializer(ptr));
}
/**
* Creates a new, empty #GstStructure with the given name.
*
* @param name The name of new structure.
*/
public Structure(String name) {
this(gst.ptr_gst_structure_empty_new(name));
}
/**
* Creates a new Structure with the given name. Parses the
* list of variable arguments and sets fields to the values listed.
* Variable arguments should be passed as field name, field type,
* and value.
*
* @param name The name of new structure.
* @param firstFieldName The name of first field to set
* @param data Additional arguments.
*/
public Structure(String name, String firstFieldName, Object... data) {
this(gst.ptr_gst_structure_new(name, firstFieldName, data));
}
/**
* Creates a Structure from a string representation.
*
* @param data A string representation of a Structure.
* @return A new Structure or null when the string could not be parsed.
*/
public static Structure fromString(String data) {
return new Structure(gst.ptr_gst_structure_from_string(data, new PointerByReference()));
}
public Structure copy() {
return gst.gst_structure_copy(this);
}
public class InvalidFieldException extends RuntimeException {
private static final long serialVersionUID = 864118748304334069L;
public InvalidFieldException(String type, String fieldName) {
super(String.format("Structure does not contain %s field '%s'", type, fieldName));
}
}
/**
* Gets ValueList field representation
* @param fieldName The name of the field.
* @return field as ValueList
*/
public ValueList getValueList(String fieldName) {
GValue val = gst.gst_structure_get_value(this, fieldName);
if (val == null) {
throw new InvalidFieldException("ValueList", fieldName);
}
return new ValueList(val);
}
public int getInteger(String fieldName) {
int[] val = { 0 };
if (!gst.gst_structure_get_int(this, fieldName, val)) {
throw new InvalidFieldException("integer", fieldName);
}
return val[0];
}
public int getInteger(String fieldName, int i) {
return getValueList(fieldName).getInteger(i);
}
public double getDouble(String fieldName) {
double[] val = { 0d };
if (!gst.gst_structure_get_double(this, fieldName, val)) {
throw new InvalidFieldException("double", fieldName);
}
return val[0];
}
public double getDouble(String fieldName, int i) {
return getValueList(fieldName).getDouble(i);
}
public String getString(String fieldName) {
return gst.gst_structure_get_string(this, fieldName);
}
public String getString(String fieldName, int i) {
return getValueList(fieldName).getString(i);
}
/**
*
* @param fieldName
* @return The boolean value for fieldName
*/
public boolean getBoolean(String fieldName) {
int[] val = { 0 };
if (!gst.gst_structure_get_boolean(this, fieldName, val)) {
throw new InvalidFieldException("boolean", fieldName);
}
return val[0] != 0;
}
public boolean getBoolean(String fieldName, int i) {
return getValueList(fieldName).getBoolean(i);
}
public Fraction getFraction(String fieldName) {
int[] numerator = { 0 };
int[] denominator = { 0 };
if (!gst.gst_structure_get_fraction(this, fieldName, numerator, denominator)) {
throw new InvalidFieldException("fraction", fieldName);
}
return new Fraction(numerator[0], denominator[0]);
}
/**
* Gets FOURCC field int representation
* @param fieldName The name of the field.
* @return FOURCC field as a 4 byte integer
*/
public int getFourcc(String fieldName) {
int[] val = { 0 };
if (!gst.gst_structure_get_fourcc(this, fieldName, val)) {
throw new InvalidFieldException("FOURCC", fieldName);
}
return val[0];
}
/**
* Gets FOURCC field String representation
* @param fieldName The name of the field.
* @return FOURCC field as a String
*/
public String getFourccString(String fieldName) {
int f = getFourcc(fieldName);
byte[] b = {(byte)((f>>0)&0xff),(byte)((f>>8)&0xff),
(byte)((f>>16)&0xff),(byte)((f>>24)&0xff)};
return new String(b);
}
/**
* Gets Range field representation
* @param fieldName The name of the field.
* @return field as Range
*/
public Range getRange(String fieldName) {
GValue val = gst.gst_structure_get_value(this, fieldName);
if (val == null) {
throw new InvalidFieldException("Range", fieldName);
}
return new Range(val);
}
public boolean fixateNearestInteger(String field, Integer value) {
return gst.gst_structure_fixate_field_nearest_int(this, field, value);
}
/**
* Sets an integer field in the structure.
*
* @param field the name of the field to set.
* @param value the value to set for the field.
*/
public void setInteger(String field, Integer value) {
gst.gst_structure_set(this, field, GType.INT, value);
}
public void setDouble(String field, Double value) {
gst.gst_structure_set(this, field, GType.DOUBLE, value);
}
public void setIntegerRange(String field, Integer min, Integer max) {
gst.gst_structure_set(this, field,
gst.gst_int_range_get_type(), min, max);
}
public void setDoubleRange(String field, Double min, Double max) {
gst.gst_structure_set(this, field,
gst.gst_double_range_get_type(), min, max);
}
/**
* Get the name of @structure as a string.
*
* @return The name of the structure.
*/
public String getName() {
return gst.gst_structure_get_name(this);
}
/**
* Sets the name of the structure to the given name.
*
* The name must not be empty, must start with a letter and can be followed
* by letters, numbers and any of "/-_.:".
*
* @param name The new name of the structure.
*/
public void setName(String name) {
gst.gst_structure_set_name(this, name);
}
/**
* Checks if the structure has the given name.
*
* @param name structure name to check for
* @return true if @name matches the name of the structure.
*/
public boolean hasName(String name) {
return gst.gst_structure_has_name(this, name);
}
/**
* Check if the {@link Structure} contains a field named fieldName.
*
* @param fieldName The name of the field to check.
* @return true if the structure contains a field with the given name.
*/
public boolean hasField(String fieldName) {
return gst.gst_structure_has_field(this, fieldName);
}
/**
* Check if the {@link Structure} contains a field named fieldName.
*
* @param fieldName The name of the field to check.
* @param fieldType The type of the field.
* @return true if the structure contains a field named fieldName and of type fieldType
*/
public boolean hasField(String fieldName, GType fieldType) {
return gst.gst_structure_has_field_typed(this, fieldName, fieldType);
}
/**
* Check if the {@link Structure} contains a field named fieldName.
*
* @param fieldName The name of the field to check.
* @param fieldType The type of the field.
* @return true if the structure contains a field named fieldName and of type fieldType
*/
public boolean hasField(String fieldName, Class fieldType) {
return gst.gst_structure_has_field_typed(this, fieldName, GType.valueOf(fieldType));
}
/**
* Check if the {@link Structure} contains an integer field named fieldName.
*
* @param fieldName The name of the field to check.
* @return true if the structure contains an integer field named fieldName
*/
public boolean hasIntField(String fieldName) {
return hasField(fieldName, GType.INT);
}
/**
* Check if the {@link Structure} contains a double field named fieldName.
*
* @param fieldName The name of the field to check.
* @return true if the structure contains a double field named fieldName
*/
public boolean hasDoubleField(String fieldName) {
return hasField(fieldName, GType.DOUBLE);
}
/**
* Removes the field with the given name from the structure.
* If the field with the given name does not exist, the structure is unchanged.
* @param fieldName The name of the field to remove.
*/
public void removeField(String fieldName) {
gst.gst_structure_remove_field(this, fieldName);
}
/**
* Removes the fields with the given names.
* If a field does not exist, the argument is ignored.
*
* @param fieldNames A list of field names to remove.
*/
public void removeFields(String... fieldNames) {
gst.gst_structure_remove_fields(this, fieldNames);
}
@Override
public String toString() {
return gst.gst_structure_to_string(this);
}
public static Structure objectFor(Pointer ptr, boolean needRef, boolean ownsHandle) {
return NativeObject.objectFor(ptr, Structure.class, needRef, ownsHandle);
}
//--------------------------------------------------------------------------
protected void disposeNativeHandle(Pointer ptr) {
gst.gst_structure_free(ptr);
}
}