Tatu Saloranta | dfd6909 | 2015-04-09 22:29:34 -0700 | [diff] [blame^] | 1 | package com.fasterxml.jackson.core.filter; |
| 2 | |
| 3 | import java.io.IOException; |
| 4 | import java.io.OutputStream; |
| 5 | import java.math.BigDecimal; |
| 6 | import java.math.BigInteger; |
| 7 | |
| 8 | import com.fasterxml.jackson.core.*; |
| 9 | import com.fasterxml.jackson.core.util.JsonParserDelegate; |
| 10 | |
| 11 | /** |
| 12 | * Specialized {@link JsonParserDelegate} that allows use of |
| 13 | * {@link TokenFilter} for outputting a subset of content that |
| 14 | * is visible to caller |
| 15 | * |
| 16 | * @since 2.6 |
| 17 | */ |
| 18 | public class FilteringParserDelegate extends JsonParserDelegate |
| 19 | { |
| 20 | /* |
| 21 | /********************************************************** |
| 22 | /* Configuration |
| 23 | /********************************************************** |
| 24 | */ |
| 25 | |
| 26 | /** |
| 27 | * Object consulted to determine whether to write parts of content generator |
| 28 | * is asked to write or not. |
| 29 | */ |
| 30 | protected TokenFilter rootFilter; |
| 31 | |
| 32 | /** |
| 33 | * Flag that determines whether filtering will continue after the first |
| 34 | * match is indicated or not: if `false`, output is based on just the first |
| 35 | * full match (returning {@link TokenFilter#INCLUDE_ALL}) and no more |
| 36 | * checks are made; if `true` then filtering will be applied as necessary |
| 37 | * until end of content. |
| 38 | */ |
| 39 | protected boolean _allowMultipleMatches; |
| 40 | |
| 41 | /** |
| 42 | * Flag that determines whether path leading up to included content should |
| 43 | * also be automatically included or not. If `false`, no path inclusion is |
| 44 | * done and only explicitly included entries are output; if `true` then |
| 45 | * path from main level down to match is also included as necessary. |
| 46 | */ |
| 47 | protected boolean _includePath; |
| 48 | |
| 49 | /* |
| 50 | /********************************************************** |
| 51 | /* State |
| 52 | /********************************************************** |
| 53 | */ |
| 54 | |
| 55 | /** |
| 56 | * Last token retrieved via {@link #nextToken}, if any. |
| 57 | * Null before the first call to <code>nextToken()</code>, |
| 58 | * as well as if token has been explicitly cleared |
| 59 | */ |
| 60 | protected JsonToken _currToken; |
| 61 | |
| 62 | /** |
| 63 | * Last cleared token, if any: that is, value that was in |
| 64 | * effect when {@link #clearCurrentToken} was called. |
| 65 | */ |
| 66 | protected JsonToken _lastClearedToken; |
| 67 | |
| 68 | /** |
| 69 | * Although delegate has its own output context it is not sufficient since we actually |
| 70 | * have to keep track of excluded (filtered out) structures as well as ones delegate |
| 71 | * actually outputs. |
| 72 | */ |
| 73 | protected TokenFilterContext _filterContext; |
| 74 | |
| 75 | /** |
| 76 | * State that applies to the item within container, used where applicable. |
| 77 | * Specifically used to pass inclusion state between property name and |
| 78 | * property, and also used for array elements. |
| 79 | */ |
| 80 | protected TokenFilter _itemFilter; |
| 81 | |
| 82 | /** |
| 83 | * Number of tokens for which {@link TokenFilter#INCLUDE_ALL} |
| 84 | * has been returned |
| 85 | */ |
| 86 | protected int _matchCount; |
| 87 | |
| 88 | /* |
| 89 | /********************************************************** |
| 90 | /* Construction, initialization |
| 91 | /********************************************************** |
| 92 | */ |
| 93 | |
| 94 | public FilteringParserDelegate(JsonParser p, TokenFilter f, |
| 95 | boolean includePath, boolean allowMultipleMatches) |
| 96 | { |
| 97 | super(p); |
| 98 | rootFilter = f; |
| 99 | // and this is the currently active filter for root values |
| 100 | _itemFilter = f; |
| 101 | _filterContext = TokenFilterContext.createRootContext(f); |
| 102 | _includePath = includePath; |
| 103 | _allowMultipleMatches = allowMultipleMatches; |
| 104 | } |
| 105 | |
| 106 | /* |
| 107 | /********************************************************** |
| 108 | /* Extended API |
| 109 | /********************************************************** |
| 110 | */ |
| 111 | |
| 112 | public TokenFilter getFilter() { return rootFilter; } |
| 113 | |
| 114 | /** |
| 115 | * Accessor for finding number of matches, where specific token and sub-tree |
| 116 | * starting (if structured type) are passed. |
| 117 | */ |
| 118 | public int getMatchCount() { |
| 119 | return _matchCount; |
| 120 | } |
| 121 | |
| 122 | /* |
| 123 | /********************************************************** |
| 124 | /* Public API, token accessors |
| 125 | /********************************************************** |
| 126 | */ |
| 127 | |
| 128 | @Override public JsonToken getCurrentToken() { return _currToken; } |
| 129 | |
| 130 | @Override public final int getCurrentTokenId() { |
| 131 | final JsonToken t = _currToken; |
| 132 | return (t == null) ? JsonTokenId.ID_NO_TOKEN : t.id(); |
| 133 | } |
| 134 | |
| 135 | @Override public boolean hasCurrentToken() { return _currToken != null; } |
| 136 | @Override public boolean hasTokenId(int id) { |
| 137 | final JsonToken t = _currToken; |
| 138 | if (t == null) { |
| 139 | return (JsonTokenId.ID_NO_TOKEN == id); |
| 140 | } |
| 141 | return t.id() == id; |
| 142 | } |
| 143 | |
| 144 | @Override public final boolean hasToken(JsonToken t) { |
| 145 | return (_currToken == t); |
| 146 | } |
| 147 | |
| 148 | @Override public boolean isExpectedStartArrayToken() { return _currToken == JsonToken.START_ARRAY; } |
| 149 | @Override public boolean isExpectedStartObjectToken() { return _currToken == JsonToken.START_OBJECT; } |
| 150 | |
| 151 | @Override public JsonLocation getCurrentLocation() { return delegate.getCurrentLocation(); } |
| 152 | @Override public JsonStreamContext getParsingContext() { return _filterContext; } |
| 153 | |
| 154 | // !!! TODO: not necessarily correct... |
| 155 | @Override public String getCurrentName() throws IOException { return delegate.getCurrentName(); } |
| 156 | |
| 157 | /* |
| 158 | /********************************************************** |
| 159 | /* Public API, token state overrides |
| 160 | /********************************************************** |
| 161 | */ |
| 162 | |
| 163 | @Override |
| 164 | public void clearCurrentToken() { |
| 165 | if (_currToken != null) { |
| 166 | _lastClearedToken = _currToken; |
| 167 | _currToken = null; |
| 168 | } |
| 169 | } |
| 170 | |
| 171 | @Override |
| 172 | public JsonToken getLastClearedToken() { return _lastClearedToken; } |
| 173 | |
| 174 | // !!! TODO: re-implement |
| 175 | @Override |
| 176 | public void overrideCurrentName(String name) { delegate.overrideCurrentName(name); } |
| 177 | |
| 178 | /* |
| 179 | /********************************************************** |
| 180 | /* Public API, traversal |
| 181 | /********************************************************** |
| 182 | */ |
| 183 | |
| 184 | // !!! TODO: re-implement |
| 185 | @Override public JsonToken nextToken() throws IOException { return delegate.nextToken(); } |
| 186 | |
| 187 | @Override |
| 188 | public JsonToken nextValue() throws IOException { |
| 189 | // Re-implemented same as ParserMinimalBase: |
| 190 | JsonToken t = nextToken(); |
| 191 | if (t == JsonToken.FIELD_NAME) { |
| 192 | t = nextToken(); |
| 193 | } |
| 194 | return t; |
| 195 | } |
| 196 | |
| 197 | /** |
| 198 | * Need to override, re-implement similar to how method defined in |
| 199 | * {@link com.fasterxml.jackson.core.base.ParserMinimalBase}, to keep |
| 200 | * state correct here. |
| 201 | */ |
| 202 | @Override |
| 203 | public JsonParser skipChildren() throws IOException |
| 204 | { |
| 205 | if (_currToken != JsonToken.START_OBJECT |
| 206 | && _currToken != JsonToken.START_ARRAY) { |
| 207 | return this; |
| 208 | } |
| 209 | int open = 1; |
| 210 | |
| 211 | // Since proper matching of start/end markers is handled |
| 212 | // by nextToken(), we'll just count nesting levels here |
| 213 | while (true) { |
| 214 | JsonToken t = nextToken(); |
| 215 | if (t == null) { // not ideal but for now, just return |
| 216 | return this; |
| 217 | } |
| 218 | if (t.isStructStart()) { |
| 219 | ++open; |
| 220 | } else if (t.isStructEnd()) { |
| 221 | if (--open == 0) { |
| 222 | return this; |
| 223 | } |
| 224 | } |
| 225 | } |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | /********************************************************** |
| 230 | /* Public API, access to token information, text |
| 231 | /********************************************************** |
| 232 | */ |
| 233 | |
| 234 | @Override public String getText() throws IOException { return delegate.getText(); } |
| 235 | @Override public boolean hasTextCharacters() { return delegate.hasTextCharacters(); } |
| 236 | @Override public char[] getTextCharacters() throws IOException { return delegate.getTextCharacters(); } |
| 237 | @Override public int getTextLength() throws IOException { return delegate.getTextLength(); } |
| 238 | @Override public int getTextOffset() throws IOException { return delegate.getTextOffset(); } |
| 239 | |
| 240 | /* |
| 241 | /********************************************************** |
| 242 | /* Public API, access to token information, numeric |
| 243 | /********************************************************** |
| 244 | */ |
| 245 | |
| 246 | @Override |
| 247 | public BigInteger getBigIntegerValue() throws IOException { return delegate.getBigIntegerValue(); } |
| 248 | |
| 249 | @Override |
| 250 | public boolean getBooleanValue() throws IOException { return delegate.getBooleanValue(); } |
| 251 | |
| 252 | @Override |
| 253 | public byte getByteValue() throws IOException { return delegate.getByteValue(); } |
| 254 | |
| 255 | @Override |
| 256 | public short getShortValue() throws IOException { return delegate.getShortValue(); } |
| 257 | |
| 258 | @Override |
| 259 | public BigDecimal getDecimalValue() throws IOException { return delegate.getDecimalValue(); } |
| 260 | |
| 261 | @Override |
| 262 | public double getDoubleValue() throws IOException { return delegate.getDoubleValue(); } |
| 263 | |
| 264 | @Override |
| 265 | public float getFloatValue() throws IOException { return delegate.getFloatValue(); } |
| 266 | |
| 267 | @Override |
| 268 | public int getIntValue() throws IOException { return delegate.getIntValue(); } |
| 269 | |
| 270 | @Override |
| 271 | public long getLongValue() throws IOException { return delegate.getLongValue(); } |
| 272 | |
| 273 | @Override |
| 274 | public NumberType getNumberType() throws IOException { return delegate.getNumberType(); } |
| 275 | |
| 276 | @Override |
| 277 | public Number getNumberValue() throws IOException { return delegate.getNumberValue(); } |
| 278 | |
| 279 | /* |
| 280 | /********************************************************** |
| 281 | /* Public API, access to token information, coercion/conversion |
| 282 | /********************************************************** |
| 283 | */ |
| 284 | |
| 285 | @Override public int getValueAsInt() throws IOException { return delegate.getValueAsInt(); } |
| 286 | @Override public int getValueAsInt(int defaultValue) throws IOException { return delegate.getValueAsInt(defaultValue); } |
| 287 | @Override public long getValueAsLong() throws IOException { return delegate.getValueAsLong(); } |
| 288 | @Override public long getValueAsLong(long defaultValue) throws IOException { return delegate.getValueAsLong(defaultValue); } |
| 289 | @Override public double getValueAsDouble() throws IOException { return delegate.getValueAsDouble(); } |
| 290 | @Override public double getValueAsDouble(double defaultValue) throws IOException { return delegate.getValueAsDouble(defaultValue); } |
| 291 | @Override public boolean getValueAsBoolean() throws IOException { return delegate.getValueAsBoolean(); } |
| 292 | @Override public boolean getValueAsBoolean(boolean defaultValue) throws IOException { return delegate.getValueAsBoolean(defaultValue); } |
| 293 | @Override public String getValueAsString() throws IOException { return delegate.getValueAsString(); } |
| 294 | @Override public String getValueAsString(String defaultValue) throws IOException { return delegate.getValueAsString(defaultValue); } |
| 295 | |
| 296 | /* |
| 297 | /********************************************************** |
| 298 | /* Public API, access to token values, other |
| 299 | /********************************************************** |
| 300 | */ |
| 301 | |
| 302 | @Override public Object getEmbeddedObject() throws IOException { return delegate.getEmbeddedObject(); } |
| 303 | @Override public byte[] getBinaryValue(Base64Variant b64variant) throws IOException { return delegate.getBinaryValue(b64variant); } |
| 304 | @Override public int readBinaryValue(Base64Variant b64variant, OutputStream out) throws IOException { return delegate.readBinaryValue(b64variant, out); } |
| 305 | @Override public JsonLocation getTokenLocation() { return delegate.getTokenLocation(); } |
| 306 | } |