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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including
all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and
Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
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*
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* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
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* or LICENSE.txt. See the License for the specific
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* file and include the License file at LICENSE.txt.
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* exception as provided by Oracle in the GPL Version 2 section of the License
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package org.glassfish.json;
import javax.json.JsonArray;
import javax.json.JsonException;
import javax.json.JsonObject;
import javax.json.JsonPointer;
import javax.json.JsonStructure;
import javax.json.JsonValue;
import java.io.Serializable;
import java.util.function.BiFunction;
/**
* This class is an immutable representation of a JSON Pointer as specified in
* RFC 6901.
*
* A JSON Pointer, when applied to a target {@link JsonValue},
* defines a reference location in the target.
* An empty JSON Pointer string defines a reference to the target itself.
* If the JSON Pointer string is non-empty, it must be a sequence
* of '/' prefixed tokens, and the target must either be a {@link JsonArray}
* or {@link JsonObject}. If the target is a {@code JsonArray}, the pointer
* defines a reference to an array element, and the last token specifies the index.
* If the target is a {@link JsonObject}, the pointer defines a reference to a
* name/value pair, and the last token specifies the name.
*
* The method {@link #getValue getValue()} returns the referenced value.
* The methods {@link #add add()}, {@link #replace replace()},
* and {@link #remove remove()} executes the operations specified in
* RFC 6902.
*
* @since 1.1
*/
public final class JsonPointerImpl implements JsonPointer, Serializable {
private static final long serialVersionUID = -8123110179640843141L;
private final String[] tokens;
private final String jsonPointer;
/**
* Constructs and initializes a JsonPointerImpl.
* @param jsonPointer the JSON Pointer string
* @throws NullPointerException if {@code jsonPointer} is {@code null}
* @throws JsonException if {@code jsonPointer} is not a valid JSON Pointer
*/
public JsonPointerImpl(String jsonPointer) {
this.jsonPointer = jsonPointer;
tokens = jsonPointer.split("/", -1); // keep the trailing blanks
if (! "".equals(tokens[0])) {
throw new JsonException(JsonMessages.POINTER_FORMAT_INVALID());
}
for (int i = 1; i < tokens.length; i++) {
String token = tokens[i];
StringBuilder reftoken = new StringBuilder();
for (int j = 0; j < token.length(); j++) {
char ch = token.charAt(j);
if (ch == '~' && j < token.length() - 1) {
char ch1 = token.charAt(j+1);
if (ch1 == '0') {
ch = '~'; j++;
} else if (ch1 == '1') {
ch = '/'; j++;
}
}
reftoken.append(ch);
}
tokens[i] = reftoken.toString();
}
}
/**
* Compares this {@code JsonPointer} with another object.
* @param obj the object to compare this {@code JsonPointer} against
* @return true if the given object is a {@code JsonPointer} with the same
* reference tokens as this one, false otherwise.
*/
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null || obj.getClass() != JsonPointerImpl.class)
return false;
return jsonPointer.equals(((JsonPointerImpl)obj).jsonPointer);
}
/**
* Returns the hash code value for this {@code JsonPointer} object.
* The hash code of this object is defined by the hash codes of it's reference tokens.
*
* @return the hash code value for this {@code JsonPointer} object
*/
@Override
public int hashCode() {
return jsonPointer.hashCode();
}
/**
* Returns {@code true} if there is a value at the referenced location in the specified {@code target}.
*
* @param target the target referenced by this {@code JsonPointer}
* @return {@code true} if this pointer points to a value in a specified {@code target}.
*/
@Override
public boolean containsValue(JsonStructure target) {
NodeReference[] refs = getReferences(target);
return refs[0].contains();
}
/**
* Returns the value at the referenced location in the specified {@code target}
*
* @param target the target referenced by this {@code JsonPointer}
* @return the referenced value in the target.
* @throws NullPointerException if {@code target} is null
* @throws JsonException if the referenced value does not exist
*/
@Override
public JsonValue getValue(JsonStructure target) {
NodeReference[] refs = getReferences(target);
return refs[0].get();
}
/**
* Adds or replaces a value at the referenced location in the specified
* {@code target} with the specified {@code value}.
*
* - If the reference is the target (empty JSON Pointer string),
* the specified {@code value}, which must be the same type as
* specified {@code target}, is returned.
* - If the reference is an array element, the specified {@code value} is inserted
* into the array, at the referenced index. The value currently at that location, and
* any subsequent values, are shifted to the right (adds one to the indices).
* Index starts with 0. If the reference is specified with a "-", or if the
* index is equal to the size of the array, the value is appended to the array.
* - If the reference is a name/value pair of a {@code JsonObject}, and the
* referenced value exists, the value is replaced by the specified {@code value}.
* If the value does not exist, a new name/value pair is added to the object.
*
*
* @param target the target referenced by this {@code JsonPointer}
* @param value the value to be added
* @return the transformed {@code target} after the value is added.
* @throws NullPointerException if {@code target} is {@code null}
* @throws JsonException if the reference is an array element and
* the index is out of range ({@code index < 0 || index > array size}),
* or if the pointer contains references to non-existing objects or arrays.
*/
@Override
public JsonStructure add(JsonStructure target, JsonValue value) {
return execute(NodeReference::add, target, value);
}
/**
* Replaces the value at the referenced location in the specified
* {@code target} with the specified {@code value}.
*
* @param target the target referenced by this {@code JsonPointer}
* @param value the value to be stored at the referenced location
* @return the transformed {@code target} after the value is replaced.
* @throws NullPointerException if {@code target} is {@code null}
* @throws JsonException if the referenced value does not exist,
* or if the reference is the target.
*/
@Override
public JsonStructure replace(JsonStructure target, JsonValue value) {
return execute(NodeReference::replace, target, value);
}
/**
* Removes the value at the reference location in the specified {@code target}
*
* @param target the target referenced by this {@code JsonPointer}
* @return the transformed {@code target} after the value is removed.
* @throws NullPointerException if {@code target} is {@code null}
* @throws JsonException if the referenced value does not exist,
* or if the reference is the target.
*/
@Override
public JsonStructure remove(JsonStructure target) {
return execute((r,v)->r.remove(), target, null);
}
/**
* Executes the operation
* @param op a {code BiFunction} used to specify the operation to execute on
* the leaf node of the Json Pointer
* @param target the target JsonStructure for this JsonPointer
* @param value the JsonValue for add and replace, can be null for getvalue and remove
*/
private JsonStructure execute(BiFunction op,
JsonStructure target, JsonValue value) {
NodeReference[] refs = getReferences(target);
JsonStructure result = op.apply(refs[0], value);
for (int i = 1; i < refs.length; i++) {
result = refs[i].replace(result);
}
return result;
}
/**
* Computes the {@code NodeReference}s for each node on the path of
* the JSON Pointer, in reverse order, starting from the leaf node
*/
private NodeReference[] getReferences(JsonStructure target) {
NodeReference[] references;
// First check if this is a reference to a JSON value tree
if (tokens.length == 1) {
references = new NodeReference[1];
references[0] = NodeReference.of(target);
return references;
}
references = new NodeReference[tokens.length-1];
JsonValue value = target;
int s = tokens.length;
for (int i = 1; i < s; i++) {
// Start with index 1, skipping the "" token
switch (value.getValueType()) {
case OBJECT:
JsonObject object = (JsonObject) value;
references[s-i-1] = NodeReference.of(object, tokens[i]);
if (i < s-1) {
value = object.get(tokens[i]);
if (value == null) {
// Except for the last name, the mapping must exist
throw new JsonException(JsonMessages.POINTER_MAPPING_MISSING(object, tokens[i]));
}
}
break;
case ARRAY:
int index = getIndex(tokens[i]);
JsonArray array = (JsonArray) value;
references[s-i-1] = NodeReference.of(array, index);
if (i < s-1 && index != -1) {
if (index >= array.size()) {
throw new JsonException(JsonMessages.NODEREF_ARRAY_INDEX_ERR(index, array.size()));
}
// The last array index in the path can have index value of -1
// ("-" in the JSON pointer)
value = array.get(index);
}
break;
default:
throw new JsonException(JsonMessages.POINTER_REFERENCE_INVALID(value.getValueType()));
}
}
return references;
}
/**
* Computes the array index
* @param token the input string token
* @return the array index. -1 if the token is "-"
* @throws JsonException if the string token is not in correct format
*/
static private int getIndex(String token) {
if (token == null || token.length() == 0) {
throw new JsonException(JsonMessages.POINTER_ARRAY_INDEX_ERR(token));
}
if (token.equals("-")) {
return -1;
}
if (token.equals("0")) {
return 0;
}
if (token.charAt(0) == '+' || token.charAt(0) == '-') {
throw new JsonException(JsonMessages.POINTER_ARRAY_INDEX_ERR(token));
}
try {
return Integer.parseInt(token);
} catch (NumberFormatException ex) {
throw new JsonException(JsonMessages.POINTER_ARRAY_INDEX_ILLEGAL(token), ex);
}
}
}
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