org.jacoco.core.internal.analysis
Class Instruction

java.lang.Object
  org.jacoco.core.internal.analysis.Instruction

public class Instruction
extends Object

Execution status of a single bytecode instruction internally used for coverage analysis. The execution status is recorded separately for each outgoing branch. Each instruction has at least one branch, for example in case of a simple sequence of instructions (by convention branch 0). Instances of this class are used in two steps:

Step 1: Building the CFG

For each bytecode instruction of a method a Instruction instance is created. In correspondence with the CFG these instances are linked with each other with the addBranch() methods. The executions status is either directly derived from a probe which has been inserted in the execution flow (addBranch(boolean, int)) or indirectly propagated along the CFG edges (addBranch(Instruction, int)).

Step 2: Querying the Coverage Status

After all instructions have been created and linked each instruction knows its execution status and can be queried with:

• getLine()
• getInstructionCounter()
• getBranchCounter()

For the purpose of filtering instructions can be combined to new instructions. Note that these methods create new Instruction instances and do not modify the existing ones.

• merge(Instruction)
• replaceBranches(Collection)

Constructor Summary

Instruction(int line)
New instruction at the given line.

Method Summary

void	addBranch(boolean executed, int branch) Adds a branch to this instruction which execution status is directly derived from a probe.
void	addBranch(Instruction target, int branch) Adds a branch to this instruction which execution status is indirectly derived from the execution status of the target instruction.
ICounter	getBranchCounter() Returns the branch coverage counter of this instruction.
ICounter	getInstructionCounter() Returns the instruction coverage counter of this instruction.
int	getLine() Returns the source line this instruction belongs to.
Instruction	merge(Instruction other) Merges information about covered branches of this instruction with another instruction.
Instruction	replaceBranches(Collection<Instruction> newBranches) Creates a copy of this instruction where all outgoing branches are replaced with the given instructions.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Instruction

public Instruction(int line)

New instruction at the given line.

Parameters:

line - source line this instruction belongs to

Method Detail

addBranch

public void addBranch(Instruction target,
                      int branch)

Adds a branch to this instruction which execution status is indirectly derived from the execution status of the target instruction. In case the branch is covered the status is propagated also to the predecessors of this instruction. Note: This method is not idempotent and must be called exactly once for every branch.

Parameters:

target - target instruction of this branch

branch - branch identifier unique for this instruction

addBranch

public void addBranch(boolean executed,
                      int branch)

Adds a branch to this instruction which execution status is directly derived from a probe. In case the branch is covered the status is propagated also to the predecessors of this instruction. Note: This method is not idempotent and must be called exactly once for every branch.

Parameters:

executed - whether the corresponding probe has been executed

branch - branch identifier unique for this instruction

getLine

public int getLine()

Returns the source line this instruction belongs to.

Returns:

corresponding source line

merge

public Instruction merge(Instruction other)

Merges information about covered branches of this instruction with another instruction.

Parameters:

other - instruction to merge with

Returns:

new instance with merged branches

replaceBranches

public Instruction replaceBranches(Collection<Instruction> newBranches)

Creates a copy of this instruction where all outgoing branches are replaced with the given instructions. The coverage status of the new instruction is derived from the status of the given instructions.

Parameters:

newBranches - new branches to consider

Returns:

new instance with replaced branches

getInstructionCounter

public ICounter getInstructionCounter()

Returns the instruction coverage counter of this instruction. It is always 1 instruction which is covered or not.

Returns:

the instruction coverage counter

getBranchCounter

public ICounter getBranchCounter()

Returns the branch coverage counter of this instruction. Only instructions with at least 2 outgoing edges report branches.

Returns:

the branch coverage counter