diff options
Diffstat (limited to 'java/src/main/java/com/google/protobuf/UnknownFieldSetLite.java')
-rw-r--r-- | java/src/main/java/com/google/protobuf/UnknownFieldSetLite.java | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/java/src/main/java/com/google/protobuf/UnknownFieldSetLite.java b/java/src/main/java/com/google/protobuf/UnknownFieldSetLite.java new file mode 100644 index 00000000..7ea84022 --- /dev/null +++ b/java/src/main/java/com/google/protobuf/UnknownFieldSetLite.java @@ -0,0 +1,297 @@ +// Protocol Buffers - Google's data interchange format +// Copyright 2008 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +package com.google.protobuf; + +import java.io.IOException; + +/** + * {@code UnknownFieldSetLite} is used to keep track of fields which were seen + * when parsing a protocol message but whose field numbers or types are + * unrecognized. This most frequently occurs when new fields are added to a + * message type and then messages containing those fields are read by old + * software that was compiled before the new types were added. + * + * <p>For use by generated code only. + * + * @author dweis@google.com (Daniel Weis) + */ +public final class UnknownFieldSetLite { + + private static final UnknownFieldSetLite DEFAULT_INSTANCE = + new UnknownFieldSetLite(ByteString.EMPTY); + + /** + * Get an empty {@code UnknownFieldSetLite}. + * + * <p>For use by generated code only. + */ + public static UnknownFieldSetLite getDefaultInstance() { + return DEFAULT_INSTANCE; + } + + /** + * Create a new {@link Builder}. + * + * <p>For use by generated code only. + */ + public static Builder newBuilder() { + return new Builder(); + } + + /** + * Returns an {@code UnknownFieldSetLite} that is the composite of {@code first} and + * {@code second}. + */ + static UnknownFieldSetLite concat(UnknownFieldSetLite first, UnknownFieldSetLite second) { + return new UnknownFieldSetLite(first.byteString.concat(second.byteString)); + } + + /** + * The internal representation of the unknown fields. + */ + private final ByteString byteString; + + /** + * Constructs the {@code UnknownFieldSetLite} as a thin wrapper around {@link ByteString}. + */ + private UnknownFieldSetLite(ByteString byteString) { + this.byteString = byteString; + } + + /** + * Serializes the set and writes it to {@code output}. + * + * <p>For use by generated code only. + */ + public void writeTo(CodedOutputStream output) throws IOException { + output.writeRawBytes(byteString); + } + + + /** + * Get the number of bytes required to encode this set. + * + * <p>For use by generated code only. + */ + public int getSerializedSize() { + return byteString.size(); + } + + @Override + public boolean equals(Object obj) { + if (this == obj) { + return true; + } + + if (obj instanceof UnknownFieldSetLite) { + return byteString.equals(((UnknownFieldSetLite) obj).byteString); + } + + return false; + } + + @Override + public int hashCode() { + return byteString.hashCode(); + } + + /** + * Builder for {@link UnknownFieldSetLite}s. + * + * <p>Use {@link UnknownFieldSet#newBuilder()} to construct a {@code Builder}. + * + * <p>For use by generated code only. + */ + public static final class Builder { + + private ByteString.Output byteStringOutput; + private CodedOutputStream output; + private boolean built; + + /** + * Constructs a {@code Builder}. Lazily initialized by + * {@link #ensureInitializedButNotBuilt()}. + */ + private Builder() {} + + /** + * Ensures internal state is initialized for use. + */ + private void ensureInitializedButNotBuilt() { + if (built) { + throw new IllegalStateException("Do not reuse UnknownFieldSetLite Builders."); + } + + if (output == null && byteStringOutput == null) { + byteStringOutput = ByteString.newOutput(100 /* initialCapacity */); + output = CodedOutputStream.newInstance(byteStringOutput); + } + } + + /** + * Parse a single field from {@code input} and merge it into this set. + * + * <p>For use by generated code only. + * + * @param tag The field's tag number, which was already parsed. + * @return {@code false} if the tag is an end group tag. + */ + public boolean mergeFieldFrom(final int tag, final CodedInputStream input) + throws IOException { + ensureInitializedButNotBuilt(); + + final int fieldNumber = WireFormat.getTagFieldNumber(tag); + switch (WireFormat.getTagWireType(tag)) { + case WireFormat.WIRETYPE_VARINT: + output.writeUInt64(fieldNumber, input.readInt64()); + return true; + case WireFormat.WIRETYPE_FIXED32: + output.writeFixed32(fieldNumber, input.readFixed32()); + return true; + case WireFormat.WIRETYPE_FIXED64: + output.writeFixed64(fieldNumber, input.readFixed64()); + return true; + case WireFormat.WIRETYPE_LENGTH_DELIMITED: + output.writeBytes(fieldNumber, input.readBytes()); + return true; + case WireFormat.WIRETYPE_START_GROUP: + final Builder subBuilder = newBuilder(); + subBuilder.mergeFrom(input); + input.checkLastTagWas( + WireFormat.makeTag(fieldNumber, WireFormat.WIRETYPE_END_GROUP)); + + output.writeTag(fieldNumber, WireFormat.WIRETYPE_START_GROUP); + subBuilder.build().writeTo(output); + output.writeTag(fieldNumber, WireFormat.WIRETYPE_END_GROUP); + return true; + case WireFormat.WIRETYPE_END_GROUP: + return false; + default: + throw InvalidProtocolBufferException.invalidWireType(); + } + } + + /** + * Convenience method for merging a new field containing a single varint + * value. This is used in particular when an unknown enum value is + * encountered. + * + * <p>For use by generated code only. + */ + public Builder mergeVarintField(int fieldNumber, int value) { + if (fieldNumber == 0) { + throw new IllegalArgumentException("Zero is not a valid field number."); + } + ensureInitializedButNotBuilt(); + try { + output.writeUInt64(fieldNumber, value); + } catch (IOException e) { + // Should never happen. + } + return this; + } + + /** + * Convenience method for merging a length-delimited field. + * + * <p>For use by generated code only. + */ + public Builder mergeLengthDelimitedField( + final int fieldNumber, final ByteString value) { + if (fieldNumber == 0) { + throw new IllegalArgumentException("Zero is not a valid field number."); + } + ensureInitializedButNotBuilt(); + try { + output.writeBytes(fieldNumber, value); + } catch (IOException e) { + // Should never happen. + } + return this; + } + + /** + * Build the {@link UnknownFieldSetLite} and return it. + * + * <p>Once {@code build()} has been called, the {@code Builder} will no + * longer be usable. Calling any method after {@code build()} will result + * in undefined behavior and can cause a {@code IllegalStateException} to be + * thrown. + * + * <p>For use by generated code only. + */ + public UnknownFieldSetLite build() { + if (built) { + throw new IllegalStateException("Do not reuse UnknownFieldSetLite Builders."); + } + + built = true; + + final UnknownFieldSetLite result; + // If we were never initialized, no data was written. + if (output == null) { + result = getDefaultInstance(); + } else { + try { + output.flush(); + } catch (IOException e) { + // Should never happen. + } + ByteString byteString = byteStringOutput.toByteString(); + if (byteString.isEmpty()) { + result = getDefaultInstance(); + } else { + result = new UnknownFieldSetLite(byteString); + } + } + + // Allow for garbage collection. + output = null; + byteStringOutput = null; + return result; + } + + /** + * Parse an entire message from {@code input} and merge its fields into + * this set. + */ + private Builder mergeFrom(final CodedInputStream input) throws IOException { + // Ensures initialization in mergeFieldFrom. + while (true) { + final int tag = input.readTag(); + if (tag == 0 || !mergeFieldFrom(tag, input)) { + break; + } + } + return this; + } + } +} |