CodedInputStream

java.lang.Object
- com.google.protobuf.CodedInputStream

```
public final class CodedInputStream
extends Object
```
Reads and decodes protocol message fields. This class contains two kinds of methods: methods that read specific protocol message constructs and field types (e.g. readTag() and readInt32()) and methods that read low-level values (e.g. readRawVarint32() and readRawBytes(int)). If you are reading encoded protocol messages, you should use the former methods, but if you are reading some other format of your own design, use the latter.

Author:

kenton@google.com Kenton Varda

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`checkLastTagWas(int value)` Verifies that the last call to readTag() returned the given tag value.
`void`	`checkRecursionLimit()`
`static int`	`decodeZigZag32(int n)` Decode a ZigZag-encoded 32-bit value.
`static long`	`decodeZigZag64(long n)` Decode a ZigZag-encoded 64-bit value.
`void`	`enableAliasing(boolean enabled)`
`int`	`getBytesUntilLimit()` Returns the number of bytes to be read before the current limit.
`int`	`getLastTag()`
`int`	`getTotalBytesRead()` The total bytes read up to the current position.
`boolean`	`isAtEnd()` Returns true if the stream has reached the end of the input.
`static CodedInputStream`	`newInstance(byte[] buf)` Create a new CodedInputStream wrapping the given byte array.
`static CodedInputStream`	`newInstance(byte[] buf, int off, int len)` Create a new CodedInputStream wrapping the given byte array slice.
`static CodedInputStream`	`newInstance(ByteBuffer buf)` Create a new CodedInputStream wrapping the given ByteBuffer.
`static CodedInputStream`	`newInstance(InputStream input)` Create a new CodedInputStream wrapping the given InputStream and using a buffer of 4096 bytes.
`static CodedInputStream`	`newInstance(InputStream input, byte[] buffer)` Create a new CodedInputStream wrapping the given InputStream and using the given buffer.
`void`	`popLimit(int oldLimit)` Discards the current limit, returning to the previous limit.
`int`	`pushLimit(int byteLimit)` Sets `currentLimit` to (current position) + `byteLimit`.
`boolean`	`readBool()` Read a `bool` field value from the stream.
`byte[]`	`readByteArray()` Read a `bytes` field value from the stream.
`ByteBuffer`	`readByteBuffer()` Read a `bytes` field value from the stream.
`ByteString`	`readBytes()` Read a `bytes` field value from the stream.
`double`	`readDouble()` Read a `double` field value from the stream.
`int`	`readEnum()` Read an enum field value from the stream.
`int`	`readFixed32()` Read a `fixed32` field value from the stream.
`long`	`readFixed64()` Read a `fixed64` field value from the stream.
`float`	`readFloat()` Read a `float` field value from the stream.
`void`	`readGroup(int fieldNumber, MessageLite.Builder builder, ExtensionRegistryLite extensionRegistry)` Read a `group` field value from the stream.
`<T extends MessageLite> T`	`readGroup(int fieldNumber, Parser<T> parser, ExtensionRegistryLite extensionRegistry)` Read a `group` field value from the stream.
`int`	`readInt32()` Read an `int32` field value from the stream.
`long`	`readInt64()` Read an `int64` field value from the stream.
`void`	`readMessage(MessageLite.Builder builder, ExtensionRegistryLite extensionRegistry)` Read an embedded message field value from the stream.
`<T extends MessageLite> T`	`readMessage(Parser<T> parser, ExtensionRegistryLite extensionRegistry)` Read an embedded message field value from the stream.
`byte`	`readRawByte()` Read one byte from the input.
`byte[]`	`readRawBytes(int size)` Read a fixed size of bytes from the input.
`int`	`readRawLittleEndian32()` Read a 32-bit little-endian integer from the stream.
`long`	`readRawLittleEndian64()` Read a 64-bit little-endian integer from the stream.
`int`	`readRawVarint32()` Read a raw Varint from the stream.
`static int`	`readRawVarint32(int firstByte, InputStream input)` Like `readRawVarint32(InputStream)`, but expects that the caller has already read one byte.
`long`	`readRawVarint64()` Read a raw Varint from the stream.
`int`	`readSFixed32()` Read an `sfixed32` field value from the stream.
`long`	`readSFixed64()` Read an `sfixed64` field value from the stream.
`int`	`readSInt32()` Read an `sint32` field value from the stream.
`long`	`readSInt64()` Read an `sint64` field value from the stream.
`String`	`readString()` Read a `string` field value from the stream.
`String`	`readStringRequireUtf8()` Read a `string` field value from the stream.
`int`	`readTag()` Attempt to read a field tag, returning zero if we have reached EOF.
`int`	`readUInt32()` Read a `uint32` field value from the stream.
`long`	`readUInt64()` Read a `uint64` field value from the stream.
`void`	`resetSizeCounter()` Resets the current size counter to zero (see `setSizeLimit(int)`).
`void`	`setInputStream(InputStream input)` Sets or replaces the input stream to wrap.
`int`	`setRecursionLimit(int limit)` Set the maximum message recursion depth.
`int`	`setSizeLimit(int limit)` Set the maximum message size.
`boolean`	`skipField(int tag)` Reads and discards a single field, given its tag value.
`boolean`	`skipField(int tag, CodedOutputStream output)` Reads a single field and writes it to output in wire format, given its tag value.
`void`	`skipMessage()` Reads and discards an entire message.
`void`	`skipMessage(CodedOutputStream output)` Reads an entire message and writes it to output in wire format.
`void`	`skipRawBytes(int size)` Reads and discards `size` bytes.

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - checkLastTagWas
```
public void checkLastTagWas(int value)
                     throws InvalidProtocolBufferException
```
    Verifies that the last call to readTag() returned the given tag value. This is used to verify that a nested group ended with the correct end tag.
    
    Throws:
    
    InvalidProtocolBufferException - value does not match the last tag.
  - checkRecursionLimit
```
public void checkRecursionLimit()
                         throws InvalidProtocolBufferException
```
    Throws:
    
    InvalidProtocolBufferException
  - decodeZigZag32
```
public static int decodeZigZag32(int n)
```
    Decode a ZigZag-encoded 32-bit value. ZigZag encodes signed integers into values that can be efficiently encoded with varint. (Otherwise, negative values must be sign-extended to 64 bits to be varint encoded, thus always taking 10 bytes on the wire.)
    
    Parameters:
    
    n - An unsigned 32-bit integer, stored in a signed int because Java has no explicit unsigned support.
    
    Returns:
    
    A signed 32-bit integer.
  - decodeZigZag64
```
public static long decodeZigZag64(long n)
```
    Decode a ZigZag-encoded 64-bit value. ZigZag encodes signed integers into values that can be efficiently encoded with varint. (Otherwise, negative values must be sign-extended to 64 bits to be varint encoded, thus always taking 10 bytes on the wire.)
    
    Parameters:
    
    n - An unsigned 64-bit integer, stored in a signed int because Java has no explicit unsigned support.
    
    Returns:
    
    A signed 64-bit integer.
  - enableAliasing
```
public void enableAliasing(boolean enabled)
```
  - getBytesUntilLimit
```
public int getBytesUntilLimit()
```
    Returns the number of bytes to be read before the current limit. If no limit is set, returns -1.
  - getLastTag
```
public int getLastTag()
```
  - getTotalBytesRead
```
public int getTotalBytesRead()
```
    The total bytes read up to the current position. Calling resetSizeCounter() resets this value to zero.
  - isAtEnd
```
public boolean isAtEnd()
                throws IOException
```
    Returns true if the stream has reached the end of the input. This is the case if either the end of the underlying input source has been reached or if the stream has reached a limit created using pushLimit(int).
    
    Throws:
    
    IOException
  - newInstance
```
public static CodedInputStream newInstance(byte[] buf)
```
    Create a new CodedInputStream wrapping the given byte array.
    
    Parameters:
    
    buf - the buffer.
    
    Returns:
    
    the instance of CodedInputStream.
  - newInstance
```
public static CodedInputStream newInstance(byte[] buf,
                                           int off,
                                           int len)
```
    Create a new CodedInputStream wrapping the given byte array slice.
    
    Parameters:
    
    buf - the buffer.
    
    off - the offset.
    
    len - the length.
    
    Returns:
    
    the instance of CodedInputStream.
  - newInstance
```
public static CodedInputStream newInstance(ByteBuffer buf)
```
    Create a new CodedInputStream wrapping the given ByteBuffer. The data starting from the ByteBuffer's current position to its limit will be read. The returned CodedInputStream may or may not share the underlying data in the ByteBuffer, therefore the ByteBuffer cannot be changed while the CodedInputStream is in use. Note that the ByteBuffer's position won't be changed by this function. Concurrent calls with the same ByteBuffer object are safe if no other thread is trying to alter the ByteBuffer's status.
  - newInstance
```
public static CodedInputStream newInstance(InputStream input)
```
    Create a new CodedInputStream wrapping the given InputStream and using a buffer of 4096 bytes.
    
    Parameters:
    
    input - the InputStream from which the CodedInputStream will be instantiated.
    
    Returns:
    
    the instance of CodedInputStream.
  - newInstance
```
public static CodedInputStream newInstance(InputStream input,
                                           byte[] buffer)
```
    Create a new CodedInputStream wrapping the given InputStream and using the given buffer.
    
    Parameters:
    
    input - the InputStream from which the CodedInputStream will be instantiated.
    
    buffer - the buffer to use.
    
    Returns:
    
    the instance of CodedInputStream.
  - popLimit
```
public void popLimit(int oldLimit)
```
    Discards the current limit, returning to the previous limit.
    
    Parameters:
    
    oldLimit - The old limit, as returned by pushLimit.
  - pushLimit
```
public int pushLimit(int byteLimit)
              throws InvalidProtocolBufferException
```
    Sets currentLimit to (current position) + byteLimit. This is called when descending into a length-delimited embedded message.
    Note that pushLimit() does NOT affect how many bytes the CodedInputStream reads from an underlying InputStream when refreshing its buffer. If you need to prevent reading past a certain point in the underlying InputStream (e.g. because you expect it to contain more data after the end of the message which you need to handle differently) then you must place a wrapper around your InputStream which limits the amount of data that can be read from it.
    
    Returns:
    
    the old limit.
    
    Throws:
    
    InvalidProtocolBufferException
  - readBool
```
public boolean readBool()
                 throws IOException
```
    Read a bool field value from the stream.
    
    Throws:
    
    IOException
  - readByteArray
```
public byte[] readByteArray()
                     throws IOException
```
    Read a bytes field value from the stream.
    
    Throws:
    
    IOException
  - readByteBuffer
```
public ByteBuffer readByteBuffer()
                          throws IOException
```
    Read a bytes field value from the stream.
    
    Throws:
    
    IOException
  - readBytes
```
public ByteString readBytes()
                     throws IOException
```
    Read a bytes field value from the stream.
    
    Throws:
    
    IOException
  - readDouble
```
public double readDouble()
                  throws IOException
```
    Read a double field value from the stream.
    
    Throws:
    
    IOException
  - readEnum
```
public int readEnum()
             throws IOException
```
    Read an enum field value from the stream. Caller is responsible for converting the numeric value to an actual enum.
    
    Throws:
    
    IOException
  - readFixed32
```
public int readFixed32()
                throws IOException
```
    Read a fixed32 field value from the stream.
    
    Throws:
    
    IOException
  - readFixed64
```
public long readFixed64()
                 throws IOException
```
    Read a fixed64 field value from the stream.
    
    Throws:
    
    IOException
  - readFloat
```
public float readFloat()
                throws IOException
```
    Read a float field value from the stream.
    
    Throws:
    
    IOException
  - readGroup
```
public void readGroup(int fieldNumber,
                      MessageLite.Builder builder,
                      @Nullable
                      ExtensionRegistryLite extensionRegistry)
               throws IOException
```
    Read a group field value from the stream.
    
    Throws:
    
    IOException
  - readGroup
```
public <T extends MessageLite> T readGroup(int fieldNumber,
                                           Parser<T> parser,
                                           ExtensionRegistryLite extensionRegistry)
                                    throws IOException
```
    Read a group field value from the stream.
    
    Throws:
    
    IOException
  - readInt32
```
public int readInt32()
              throws IOException
```
    Read an int32 field value from the stream.
    
    Throws:
    
    IOException
  - readInt64
```
public long readInt64()
               throws IOException
```
    Read an int64 field value from the stream.
    
    Throws:
    
    IOException
  - readMessage
```
public void readMessage(MessageLite.Builder builder,
                        ExtensionRegistryLite extensionRegistry)
                 throws IOException
```
    Read an embedded message field value from the stream.
    
    Throws:
    
    IOException
  - readMessage
```
public <T extends MessageLite> T readMessage(Parser<T> parser,
                                             ExtensionRegistryLite extensionRegistry)
                                      throws IOException
```
    Read an embedded message field value from the stream.
    
    Throws:
    
    IOException
  - readRawByte
```
public byte readRawByte()
                 throws IOException
```
    Read one byte from the input.
    
    Throws:
    
    InvalidProtocolBufferException - The end of the stream or the current limit was reached.
    
    IOException
  - readRawBytes
```
public byte[] readRawBytes(int size)
                    throws IOException
```
    Read a fixed size of bytes from the input.
    
    Throws:
    
    InvalidProtocolBufferException - The end of the stream or the current limit was reached.
    
    IOException
  - readRawLittleEndian32
```
public int readRawLittleEndian32()
                          throws IOException
```
    Read a 32-bit little-endian integer from the stream.
    
    Throws:
    
    IOException
  - readRawLittleEndian64
```
public long readRawLittleEndian64()
                           throws IOException
```
    Read a 64-bit little-endian integer from the stream.
    
    Throws:
    
    IOException
  - readRawVarint32
```
public int readRawVarint32()
                    throws IOException
```
    Read a raw Varint from the stream. If larger than 32 bits, discard the upper bits.
    
    Throws:
    
    IOException
  - readRawVarint32
```
public static int readRawVarint32(int firstByte,
                                  InputStream input)
                           throws IOException
```
    Like readRawVarint32(InputStream), but expects that the caller has already read one byte. This allows the caller to determine if EOF has been reached before attempting to read.
    
    Throws:
    
    IOException
  - readRawVarint64
```
public long readRawVarint64()
                     throws IOException
```
    Read a raw Varint from the stream.
    
    Throws:
    
    IOException
  - readSFixed32
```
public int readSFixed32()
                 throws IOException
```
    Read an sfixed32 field value from the stream.
    
    Throws:
    
    IOException
  - readSFixed64
```
public long readSFixed64()
                  throws IOException
```
    Read an sfixed64 field value from the stream.
    
    Throws:
    
    IOException
  - readSInt32
```
public int readSInt32()
               throws IOException
```
    Read an sint32 field value from the stream.
    
    Throws:
    
    IOException
  - readSInt64
```
public long readSInt64()
                throws IOException
```
    Read an sint64 field value from the stream.
    
    Throws:
    
    IOException
  - readString
```
public String readString()
                  throws IOException
```
    Read a string field value from the stream. If the stream contains malformed UTF-8, replace the offending bytes with the standard UTF-8 replacement character.
    
    Throws:
    
    IOException
  - readStringRequireUtf8
```
public String readStringRequireUtf8()
                             throws IOException
```
    Read a string field value from the stream. If the stream contains malformed UTF-8, throw exception InvalidProtocolBufferException.
    
    Throws:
    
    IOException
  - readTag
```
public int readTag()
            throws IOException
```
    Attempt to read a field tag, returning zero if we have reached EOF. Protocol message parsers use this to read tags, since a protocol message may legally end wherever a tag occurs, and zero is not a valid tag number.
    
    Throws:
    
    IOException
  - readUInt32
```
public int readUInt32()
               throws IOException
```
    Read a uint32 field value from the stream.
    
    Throws:
    
    IOException
  - readUInt64
```
public long readUInt64()
                throws IOException
```
    Read a uint64 field value from the stream.
    
    Throws:
    
    IOException
  - resetSizeCounter
```
public void resetSizeCounter()
```
    Resets the current size counter to zero (see setSizeLimit(int)).
  - setInputStream
```
public void setInputStream(InputStream input)
```
    Sets or replaces the input stream to wrap.
    This CodedInputStream is reset to its initial state. The same buffer will be used to read from the new input stream.
    
    Parameters:
    
    input - the InputStream that this CodedInputStream will wrap.
    
    Throws:
    
    IllegalStateException - if this CodedInputStream was created with an immutable buffer.
  - setRecursionLimit
```
public int setRecursionLimit(int limit)
```
    Set the maximum message recursion depth. In order to prevent malicious messages from causing stack overflows, CodedInputStream limits how deeply messages may be nested. The default limit is 64.
    
    Returns:
    
    the old limit.
  - setSizeLimit
```
public int setSizeLimit(int limit)
```
    Set the maximum message size. In order to prevent malicious messages from exhausting memory or causing integer overflows, CodedInputStream limits how large a message may be. The default limit is 64MB. You should set this limit as small as you can without harming your app's functionality. Note that size limits only apply when reading from an InputStream, not when constructed around a raw byte array (nor with ByteString.newCodedInput()).
    If you want to read several messages from a single CodedInputStream, you could call resetSizeCounter() after each one to avoid hitting the size limit.
    
    Returns:
    
    the old limit.
  - skipField
```
public boolean skipField(int tag)
                  throws IOException
```
    Reads and discards a single field, given its tag value.
    
    Returns:
    
    false if the tag is an endgroup tag, in which case nothing is skipped. Otherwise, returns true.
    
    Throws:
    
    IOException
  - skipField
```
public boolean skipField(int tag,
                         CodedOutputStream output)
                  throws IOException
```
    Reads a single field and writes it to output in wire format, given its tag value.
    
    Returns:
    
    false if the tag is an endgroup tag, in which case nothing is skipped. Otherwise, returns true.
    
    Throws:
    
    IOException
  - skipMessage
```
public void skipMessage()
                 throws IOException
```
    Reads and discards an entire message. This will read either until EOF or until an endgroup tag, whichever comes first.
    
    Throws:
    
    IOException
  - skipMessage
```
public void skipMessage(CodedOutputStream output)
                 throws IOException
```
    Reads an entire message and writes it to output in wire format. This will read either until EOF or until an endgroup tag, whichever comes first.
    
    Throws:
    
    IOException
  - skipRawBytes
```
public void skipRawBytes(int size)
                  throws IOException
```
    Reads and discards size bytes.
    
    Throws:
    
    InvalidProtocolBufferException - The end of the stream or the current limit was reached.
    
    IOException

Class CodedInputStream

Method Summary

Methods inherited from class java.lang.Object

Method Detail

checkLastTagWas

checkRecursionLimit

decodeZigZag32

decodeZigZag64

enableAliasing

getBytesUntilLimit

getLastTag

getTotalBytesRead

isAtEnd

newInstance

newInstance

newInstance

newInstance

newInstance

popLimit

pushLimit

readBool

readByteArray

readByteBuffer

readBytes

readDouble

readEnum

readFixed32

readFixed64

readFloat

readGroup

readGroup

readInt32

readInt64

readMessage

readMessage

readRawByte

readRawBytes

readRawLittleEndian32

readRawLittleEndian64

readRawVarint32

readRawVarint32

readRawVarint64

readSFixed32

readSFixed64

readSInt32

readSInt64

readString

readStringRequireUtf8

readTag

readUInt32

readUInt64

resetSizeCounter

setInputStream

setRecursionLimit

setSizeLimit

skipField

skipField

skipMessage

skipMessage

skipRawBytes